Search

Some copper(II) and zinc(II) complexes with oxindolimine ligands were tested regarding their trypanocidal properties. These complexes have already shown good biological activity in the inhibition of tumor cell proliferation, having DNA and mitochondria as main targets, through an oxidative mechanism, and inducing apoptosis. Herein, we demonstrate that they also have significant activity against the infective trypomastigote forms and the intracellular amastigote forms of T. cruzi, modulated by the metal ion as well as by the oxindolimine ligand. Selective indexes (LC50/IC50) determined for both zinc(II) and copper(II) complexes, are higher after 24 or 48 h incubation with trypomastigotes, in comparison to traditional drugs used in clinics, such as benznidazole, and other metal-based compounds previously reported in the literature. Additionally, tests against amastigotes indicated infection index <10% (% of infected macrophages/average number of amastigotes per macrophage), after 24 or 48 h in the presence of zinc(II) (60–80 µM) or analogous copper(II) complexes (10–25 µM). The copper complexes exhibit further oxidative properties, being able to damage DNA, proteins and carbohydrates, in the presence of hydrogen peroxide, with the generation of hydroxyl radicals. This redox reactivity could explain its better performance towards the parasites in relation to the zinc analogs. However, both copper and zinc complexes display good selective indexes, indicating that the influence of the ligand is also crucial, and is probably related to the inhibition of some crucial proteins. [ABSTRACT FROM AUTHOR]

Summary: Background: Hair‐straightening treatments may involve the use of thermal devices, which potentially cause damages in the cuticle and cortex of the hair fibers. Particularly, the heat causes denaturation of the α‐keratin and the degradation of the components of the hair cortex. Objectives: The aim of this study was to evaluate the effect of heating on the cuticle and cortex of the Caucasian and Asian virgin hair by using heat iron flat. Methods: The effects of the heating in the tresses of Caucasian and Asian virgin hair were analyzed by thermogravimetry/differential scanning calorimetry‐Fourier transform infrared/mass spectrometry (TG/DSC‐MS/FTIR), protein loss analysis (PLA), Fourier transform infrared (FTIR‐ATR), and scanning electron microscope (SEM). Results: TG/DSC‐MS/FTIR results were: formation of the H2O between 25‐170°C and CO2, SCO and H2S from 200°C. Denaturation temperature = 237°C. Protein loss: Asian hair>Caucasian hair. Data presented statistically significant alterations, α = 5, P ≤ 0.05, n = 3. FTIR‐ATR: changes in the secondary structural conformation of the protein of hair cuticle. SEM: heat caused damage to hair cuticle. Conclusions: The results evidenced the importance of the control of temperature in the procedures involving heat. The damage caused by thermal devices showed be dependent of the ethnicity analyzed (Caucasian and Asian hair). [ABSTRACT FROM AUTHOR]

Functionalized MCM-41 is a class of new nanoporous biomaterials extensively studied as drug carriers of a diversity of therapeutic agents due to its suitable properties. In the present study, two oxindolimine complexes based on copper(ii) and zinc(ii) were immobilized in two selective delivery systems, namely, unmodified and modified MCM-41, which can act as carriers of water-insoluble anticancer metallodrugs. Morphological and structural characterizations of these materials were accomplished, and their cytotoxic effect was evaluated on three different cancer cell lines, SKMEL-147, SKMEL-05 and HeLa, in comparison to a non-tumor cell line (fibroblast P4). Cytotoxicity assays showed that both complexes coordinated to the modified matrix were more active and selective than those immobilized into the unmodified matrix, particularly toward SKMEL-147 cells. In contrast, P4 cells were much less affected by the presence of these compounds, with very high IC50 values. Further, the release of the complexes from these materials was monitored in vitro by X-ray fluorescence, which indicated a significant delivery after 2 h at 37 °C. By using CytoViva™ images, it was possible to observe the presence of such nanoparticles inside the cells, as well as the formation of apoptotic bodies due to the action of these antitumor compounds. A high damage on the nucleus was verified by comet and DNA cleavage assays, pointing to DNA as an important target of such metallodrugs. The matrices also contribute to the potential therapeutic action of these metal complexes, significantly increasing their cytotoxicity against melanoma and cervical carcinoma cells. [ABSTRACT FROM AUTHOR]