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51.
Rufinamide (RUF) was characterized in terms of cyclodextrin (CD) complexation in order to improve its aqueous solubility. Binary systems of RUF with three CDs—β-cyclodextrin (β-CD), randomly methylated-β-cyclodextrin (RAMEB) and sulfobutylether-β-cyclodextrin (SBE-β-CD)—were characterized with a wide variety of analytical techniques. Liquid state characterization was carried out by complementary techniques such as nuclear magnetic resonance spectroscopy (NMR), capillary electrophoresis (CE), mass spectrometry (MS) and phase solubility studies. The latter revealed that the stability of the complexes decreased in the order of RAMEB?>?β-CD?>?SBE-β-CD. AL-type diagrams were obtained in all cases, characteristic of 1:1 stoichiometry, with a maximum of over 15-fold increase in RUF solubility, when complexed with RAMEB. NMR Job plot and MS studies confirmed phase solubility results, regarding the binding stoichiometry. 1H NMR and 2D ROESY investigations revealed the inclusion of the triazole moiety of RUF, confirmed by molecular modeling. Solid state complexation in 1:1 molar ratio was carried out by kneading method and investigated by differential scanning calorimetry (DSC) and infrared spectroscopy (IR). Comparative dissolution studies indicated an over two-fold improvement in dissolution efficacy of the kneaded products, when compared to the pure drug. Results of the present study might pave the way for a drug formulation with improved bioavailability.  相似文献   
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We recently showed that intranasal phototherapy represents an efficient therapeutic modality for the treatment of patients with seasonal allergic rhinitis (SAR). The aim of this pilot study was to compare the efficacy of intranasal phototherapy with that of the new generation antihistamine fexofenadine HCl in SAR. A randomized open study was conducted in patients with a history of moderate-to-severe ragweed-induced SAR. Thirty-one patients were randomly assigned to receive either intranasal irradiation three times a week for 2 weeks, or 180 mg fexofenadine HCl per day for 2 weeks. Each patient kept a diary of symptoms for nasal obstruction, nasal itching, rhinorrhea, sneezing and palate itching. Total nasal score (TNS), a sum of scores for nasal symptoms, was also calculated. In the rhinophototherapy group the individual scores significantly decreased compared with baseline for all of the parameters. In the fexofenadine HCl group none of the scores improved significantly at the end of the treatment except sneezing. TNS was significantly decreased in the rhinophototherapy group, but no significant change was observed in the fexofenadine HCl group after 2 weeks of treatment. In conclusion, we found that intranasal phototherapy is more efficient than fexofenadine HCl in reducing clinical symptoms for SAR.  相似文献   
54.
Microanalytical methods suitable for the determination of Fe, Cu in HT-29 (human colon adenocarcinoma) cells treated with different iron compounds (Fe(II) sulfate, Fe(III) chloride, Fe(III) citrate and Fe(III) transferrin) and cultured in medium supplemented or not with 10% (v/v) fetal calf serum (FCS) by total reflection X-ray fluorescence spectrometry (TXRF) and simultaneous graphite furnace atomic absorption spectrometry (GF-AAS) were developed. The developed TXRF method was also suitable for Zn determination in the samples. The main advantage of the proposed methods is the execution of all sample preparation steps following incubation and prior to the elemental analysis in the same Eppendorf tubes. Sample preparation was performed at microscale (115 μL sample volume) with 65% nitric acid and 30% hydrogen peroxide. According to scanning electron microscopic measurements, the organic matrix of the cell samples could be eliminated to the extent that accurate results were obtained for Cu and Fe by analyzing the same samples by TXRF and GF-AAS. Concerning the iron uptake, HT-29 cells incubated in FCS-free medium contained Fe in cca. 5-50 times higher amounts compared to cells cultured in FCS supplemented medium. Pronounced differences in the iron uptake compared to the iron supply (inorganic vs. organic chelated as well as iron(II) vs. iron(III)) were observed in the case of cell lines incubated in FCS-free medium.  相似文献   
55.
The carbene concentration in 1-ethyl-3-methylimidazolium-acetate ionic liquid is sufficiently high to act as a catalyst in benzoin condensation, hydroacylation and also in oxidation of an alcohol by using CO(2) and air. This observation reveals the potential of ionic liquid organocatalysts, uniting the beneficial properties of these two families of compounds.  相似文献   
56.
The paper deals with the equality problem of quasi-arithmetic and Lagrangian means which is to determine all pairs of continuous strictly monotone functions φ,ψ:IR such that, for all x,yI,
  相似文献   
57.
Let X be a real linear space and $D\subseteq X$ be a nonempty convex subset. Given an error function E:[0,1]×(D?D)?????{+??} and an element $t\in\left]0,1\right[$ , a function f:D??? is called (E,t)-convex if $$f(tx+(1-t)y)\le tf(x)+(1-t)f(y)+E(t,x-y)$$ for all x,y??D. The main result of this paper states that, for all a,b??(???{0})+{0,t,1?t} such that {a,b,a+b}??????, every (E,t)-convex function is also $\big(F,\frac{a}{a+b}\big)$ -convex, where $$F(s,u):=\frac{{(a+b)}^2s(1-s)}{t(1-t)}E\left(t,\frac{u}{a+b}\right),\qquad (u\in (D-D), \, s\in\left]0,1\right[).$$ As a consequence, under further assumptions on E, the strong and approximate convexity properties of (E,t)-convex functions can be strengthened.  相似文献   
58.
A simple plan-view sample preparation technique for transmission electron microscopy (TEM) specimens is proposed for thin films by tearing-off the film with adhesive tape. The demand for very thin samples is highest for nanostructured materials where the structure of 2-5 nm sized features (grains) needs to be resolved; therefore, overlapping of nanometer-sized features should be avoided. The method provides thin areas at the fracture edges of plan-view specimens with thickness in the range of the grain size in the film allowing for artifact free high-resolution TEM imaging. Nanostructured materials typically fracture between the grains providing areas with the thickness of the grain size. Besides the swiftness of the method, the samples are free of surface amorphization artifacts, which can occur in ion beam milling up to 1 nm depth even at low energy ion bombardment. The thin film tear-off technique is demonstrated on a CuMn alloy thin film with grain size of 2 nm.  相似文献   
59.
Aequationes mathematicae - Given two functions $$f,g:I\rightarrow \mathbb {R}$$ and a probability measure $$\mu $$ on the Borel subsets of [0, 1], the two-variable mean $$M_{f,g;\mu...  相似文献   
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