Viscosities of Some Saccharides in Aqueous Solutions of Phosphate-Based Inorganic Salts

The viscosities η of some monosaccharides, their methyl- and deoxy- derivatives, disaccharides, and trisaccharides have been measured in (0.25, 0.5, 1.0, and 1.25) mol·kg^–1 aqueous solutions of potassium phosphate (KH₂PO₄) and (0.5, 1.0, 1.5, and 2.0) mol·kg^–1 aqueous solutions of sodium phosphate (NaH₂PO₄) and ammonium phosphate (NH₄H₂PO₄) monobasic salts, and potassium phosphate (K₃PO₄) tribasic salt over the temperature range (288.15 to 318.15) K and at atmospheric pressure, <i>P</i> = 0.1 MPa. The viscosity data have been utilized to calculate the Jones–Dole viscosity <i>B</i>-coefficients and their corresponding coefficients of transfer, Δ_t<i>B</i>. The Δ_t<i>B</i> values were found to be positive and their magnitudes vary depending on the nature of solutes and cosolutes. The d<i>B</i>/d<i>T</i> coefficients and pair η_AB and triplet η_ABB interaction coefficients have also been calculated and discussed in terms of solute–solvent/cosolute interactions. The results have been compared in phosphate-based salts on the basis of the nature of the cation and anion

Studies on the Interactions of Saccharides and Methyl Glycosides with Lithium Chloride in Aqueous Solutions at (288.15 to 318.15) K

Standard partial molar volumes, <i>V</i>₂^o, at infinite dilution and viscosity <i>B</i>-coefficients (employing the Jones–Dole equation) have been calculated from the respective density and efflux time measurements for various solutes (mono-, di-, and trisaccharides, and their derivatives; methyl glycosides) in aqueous solutions of lithium chloride of (0.5, 1.0, 2.0, and 3.0) mol·kg^–1 at temperatures of (288.15 to 318.15) K. The corresponding transfer parameters, interaction coefficients, partial molar expansibilities, and d<i>B</i>/d<i>T</i> coefficients have been evaluated and discussed in terms of the solute–solvent and solute–cosolute interactions. The results have been compared for the solutes studied in the presence of (1:1 and 1:2/2:1) electrolytes to arrive at the conclusions of how these solutes interact with the mono- and divalent cations

Návrh modelu standardizace popisu pracovních pozic - plánovaných míst v informačním systému SAP R/3 HR

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Ekonomická fakulta. Katedra (155) informatiky v ekonomic

Imaging Sites of Inhibition of Proteolysis in Pathomimetic Human Breast Cancer Cultures by Light-Activated Ruthenium Compound

<div><p>The cysteine protease cathepsin B has been causally linked to progression and metastasis of breast cancers. We demonstrate inhibition by a dipeptidyl nitrile inhibitor (compound <b>1)</b> of cathepsin B activity and also of pericellular degradation of dye-quenched collagen IV by living breast cancer cells. To image, localize and quantify collagen IV degradation in real-time we used 3D pathomimetic breast cancer models designed to mimic the <i>in vivo</i> microenvironment of breast cancers. We further report the synthesis and characterization of a caged version of compound <b>1</b>, [Ru(bpy)₂(<b>1</b>)₂](BF₄)₂ (compound <b>2</b>), which can be photoactivated with visible light. Upon light activation, compound <b>2</b>, like compound <b>1</b>, inhibited cathepsin B activity and pericellular collagen IV degradation by the 3D pathomimetic models of living breast cancer cells, without causing toxicity. We suggest that caged inhibitor <b>2</b> is a prototype for cathepsin B inhibitors that can control both the site and timing of inhibition in cancer.</p></div

Changes to the electronic absorption of compound 2 (25 μM) in a 2% acetone aqueous solution at irradiation times, t_irr, of 0, 3, 5, 7, 10 and 15 min (λ_irr ≥ 395 nm); the * denotes the mono-aqua intermediate.

<p>Inset: t_irr = 0.0, 0.5, 1.5, and 3.0 min.</p

Synthesis of the ruthenium-caged, nitrile-based inhibitor 2.

<p>Synthesis of the ruthenium-caged, nitrile-based inhibitor 2.</p

The ruthenium complex <i>cis</i>-[Ru(bpy)₂(MeCN)₂](PF₆)₂ (3) used for caging of inhibitor 2 does not affect degradation of DQ-collagen IV by 3D MAME cultures of breast carcinoma cells.

<p>(A) Top view of representative 3D reconstruction of 16 contiguous fields of MDA-MB-231 breast carcinoma structures (nuclei, blue) and associated degradation fragments of DQ-collagen IV (green) at 4 days of culture. Panels from left to right are DMSO control, dark-exposed ruthenium complex and light-exposed ruthenium complex. (B) Hs578T breast carcinoma structures (nuclei, blue) and associated degradation fragments of DQ-collagen IV (green) at 4 days of culture. See A for further details. (C) Quantification of degraded DQ-collagen IV per cell in MDA-MB-231 (left) and Hs578T (right) structures incubated with DMSO (negative control), dark-exposed ruthenium complex or light-exposed ruthenium complex. Data shown are from 3 independent experiments (48 fields); mean ± SD.</p

Uncaged inhibitor 1 reduces total and pericellular degradation, but not intracellular degradation of DQ-collagen IV by 3D MAME cultures of breast carcinoma cells.

<p>Quantification of degraded collagen IV in entire 3D volume of MDA-MB-231 and Hs578T structures at 4 days of culture: total degraded collagen IV, black bars; pericellular degraded collagen IV, open bars; and intracellular degraded collagen IV, gray bars. DMSO (negative control), CA074/CA074Me (5 μM each; positive control) and uncaged inhibitor 1. Data shown are from 3 independent experiments (48 fields); * p < 0.05; mean ± SD.</p

Uncaged inhibitor 1 reduces degradation of DQ-collagen IV by 3D MAME cultures of breast carcinoma cells.

<p>(A) Top view of representative 3D reconstruction of 16 contiguous fields of MDA-MB-231 breast carcinoma structures (nuclei, blue) and associated degradation fragments of DQ-collagen IV (green) at 4 days of culture. Panels from left to right are DMSO control and cysteine protease inhibitors (middle: 5 μM each of CA074 + CA074Me; right: uncaged inhibitor 1). (B) Hs578T breast carcinoma structures (nuclei, blue) and associated degradation fragments of DQ-collagen IV (green) at 4 days of culture. See A for further details. (C) Quantification of degraded DQ-collagen IV per cell in MDA-MB-231 (left) and Hs578T (right) structures exposed to DMSO (negative control), CA074/CA074Me (5 μM each; positive control) and uncaged inhibitor <b>1</b>. Data shown are from 3 independent experiments (48 fields); * ≤ 0.05; mean ± SD.</p

Light activation of caged inhibitor 2 reduces degradation of DQ-collagen IV by 3D MAME cultures of breast carcinoma cells.

<p>(A) Top view of representative 3D reconstruction of 16 contiguous fields of MDA-MB-231 breast carcinoma structures (nuclei, blue) and associated degradation fragments of DQ-collagen IV (green) at 4 days of culture. Panels from left to right are DMSO control, dark-exposed caged inhibitor <b>2</b> and light-exposed caged inhibitor <b>2</b>. (B) Hs578T breast carcinoma structures (nuclei, blue) and associated degradation fragments of DQ-collagen IV (green) at 4 days of culture. See A for further details. (C) Quantification of degraded DQ-collagen IV per cell in MDA-MB-231 (left) and Hs578T (right) structures incubated with DMSO (negative control), dark-exposed caged inhibitor <b>2</b> or light-exposed caged inhibitor <b>2</b>. Data shown are from 3 independent experiments (48 fields); *p ≤ 0.05; **p ≤ 0.005; mean ± SD.</p