Unusual Enhancement of Doxorubicin Activity on Co-Delivery with Polyhedral Oligomeric Silsesquioxane (POSS)

Polyhedral oligomeric silsesquioxane (POSS), bearing eight 3-chloroammoniumpropyl substituents, was studied as a potential nanocarrier in co-delivery systems with doxorubicin (DOX). The toxicity of doxorubicin and POSS:DOX complexes at four different molar ratios (1:1; 1:2, 1:4, 1:8) towards microvascular endothelial cells (HMEC-1), breast cancer cells (MCF-7), and human cervical cancer endothelial cells (HeLa) was determined. The rate of penetration of the components into the cells, their cellular localization and the hydrodynamic diameter of the complexes was also determined. A cytotoxicity profile of POSS:DOX complexes indicated that the POSS:DOX system at the molar ratio of 1:8 was more effective than free DOX. Confocal images showed that DOX co-delivery with POSS allowed for more effective penetration of doxorubicin through the cell membrane. Taking all the results into account, it can be claimed that the polyhedral oligomeric silsesquioxane (T8-POSS) is a promising, complex nanocarrier for doxorubicin delivery

Conjugating Biotin to Ruthenium(II) Arene Units via Phosphine Ligand Functionalization

Two-step functionalization of 4-diphenylphosphino benzoic acid with biotin afforded 2-(biotinyloxy)ethyl 4-(diphenylphosphanyl)benzoate (LP), that was subsequently used to synthesize the Ru(II) arene complexes [RuCl2(η6-p-cymene)(LP)] (1), [Ru(C2O4)(η6-p-cymene)(LP)] (2) and [Ru(curc)(η6-p-cymene)(LP)]NO3 ([3]NO3), the latter incorporating curcumin (curcH) as an additional bioactive fragment. [Ru(curc)(η6-p-cymene)(PPh3)]NO3 ([4]NO3) was also prepared as a reference compound. Compounds 2 and [3]NO3 exhibited excellent stability in water/DMSO solution while being slowly activated in the cell culture medium over 72 hours. Together with LP, they were therefore assessed for their antiproliferative activity towards a panel of cancer cell lines, with different levels of biotin transporter expression. The apparent affinity of the compounds towards avidin varies, and their antiproliferative activity does not correlate with biotin transporter expression, although it is systematically enhanced when biotin-free cell culture medium is used

Модель смешанного обучения в преподавании дисциплины "Методы получения чистых веществ"

Данная работа посвящена использованию модели смешанного обучения в преподавании дисциплины "Методы получения чистых веществ" на английском языке. Исследовались элементы смешанного обучения, стратегия организации образовательного процесса, план учебной деятельности. Подробно описаны виды учебной деятельности и подобраны формы организации процесса. Для каждого вида деятельности определены уровни таксономии Блума. Показаны преимущества модели смешанного обучения в преподавании лабораторных работ для студентов инженерной специальности

Conjugating Biotin to Ruthenium(II) Arene Units via Phosphine Ligand Functionalization

Two-step functionalization of 4-diphenylphosphino benzoic acid with biotin afforded 2-(biotinyloxy)ethyl 4-(diphenylphosphanyl)benzoate (LP), that was subsequently used to synthesize the Ru(II) arene complexes [RuCl2(eta(6)-p-cymene)(LP)] (1), [Ru(C2O4)(eta(6)-p-cymene)(LP)] (2) and [Ru(curc)(eta(6)-p-cymene)(LP)]NO3 ([3]NO3), the latter incorporating curcumin (curcH) as an additional bioactive fragment. [Ru(curc)(eta(6)-p-cymene)(PPh3)]NO3 ([4]NO3) was also prepared as a reference compound. Compounds 2 and [3]NO3 exhibited excellent stability in water/DMSO solution while being slowly activated in the cell culture medium over 72 hours. Together with LP, they were therefore assessed for their antiproliferative activity towards a panel of cancer cell lines, with different levels of biotin transporter expression. The apparent affinity of the compounds towards avidin varies, and their antiproliferative activity does not correlate with biotin transporter expression, although it is systematically enhanced when biotin-free cell culture medium is used

Methodology for the measurement of antioxidant capacity of coffee : a validated platform composed of three complementary antioxidant assays

A platform composed of three complementary and validated antioxidant assays is proposed for the routine and fast assessment of the antioxidant capacity of coffee brews. Firstly, a brief review of the principles underlying antioxidant measurements in foods, and the rationale behind the development of an analytical platform for measuring the antioxidant capacity of coffee is given. A range of complementary methods is described based on either hydrogen atom or electron transfer reactions. Secondly, three total antioxidant capacity (TAC) assays are recommended for the platform. Two are based on electron-transfer reactions—the Folin–Ciocalteu (FC) assay for total phenols, and the ABTS assay, which on oxidation forms the cationic chromophore, 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonate) (ABTS•+). The third, which is based on hydrogen-atom transfer, is the oxygen radical absorbance capacity (ORAC), in which the antioxidant and the substrate fluorescein compete for thermally generated peroxyl radicals after their formation by decomposition of 2,​2′-​azobis-​2-​amidinopropane,​dihydrochloride (AAPH). Finally, validated protocols for conducting these three assays, using flow injection analysis (FIA), are presented along with actual results to illustrate their reproducibility and robustness. The three assays are combined into an analytical platform to profile and compare the antioxidant potential of a series of roasted coffee samples. Antioxidant values obtained with the same dark-roast coffee are 2103, 710, and 5868 gallic acid equivalents (GAE) for the FC, ABTS, and ORAC assays, respectively. These numbers thus reflect the different types of chemical reaction that are performed, and illustrate the fact that assays for TAC are actually selective (and hence complementary) for specific types of antioxidant molecule

Low energy and carbohydrate intake associated with higher total antioxidant capacity in apparently healthy adults.

Objectives: The aim of this study was to investigate the associations between plasma total antioxidant capacity (TAC) and anthropometric, biochemical, clinical, and dietary measurements in young and apparently healthy individuals. Methods: We evaluated 156 individuals (91 women and 65 men; ages 23.1 _ 3.5 y; body mass index 22 _ 2.9 kg/m2) for anthropometrics, biochemical markers, clinical, dietary, and some components of the antioxidant defense system, including the plasma TAC. Statistical analyses were performed to detect differences between individuals with TAC higher and lower than the mean value and to screen the associations between TAC and variables of interest. A linear regression model was fitted to identify TAC predictors. Results: Daily caloric intake and macronutrient consumption were lower in individuals who exhibited the highest TAC values (P < 0.05). Linear regression analysis showed that daily calories and carbohydrate intake was a possible negative TAC predictor (P < 0.05). Nevertheless, there was no difference in the values of oxidized low-density lipoprotein in the individuals separated by means of TAC. In contrast, individuals whose plasma TAC values were above the mean showed higher low-density lipoprotein cholesterol concentrations, total cholesterol/high-density lipoprotein cholesterol values, and selenium in nails (P < 0.05). Conclusions: In physiological conditions, the caloric intake level seems to be an important factor to act in the modulation of plasma TAC, before establishing anthropometric impairments of body or metabolic composition, or both. Additionally, the plasma TAC increase may be able to act as a compensatory mechanism