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The synthesis, characterization, acute toxicity, antitumor activity, and histopathological analysis of a novel dinuclear platinum(2+) complex - [Pt(DACH-κ2N)µ-(C4H2O6-κ4O)Pt(DACH-κ2N)] - is reported. Through acute toxicity tests, it was possible to place the platinum complexes into categories according to the OECD protocol. The dinuclear complex was classified in category 2 (cisplatin - category 1; and oxaliplatin - category 2). Analyzing the interaction between dsDNA and dinuclear complex was observed an Tm increase, suggesting that the dinuclear complex-dsDNA interact probably through of the interstrand form. Evaluations of tumor masses extracted from mice inoculated with Ehrlich carcinoma demonstrated a percent of tumor inhibition similar for cisplatin and oxaliplatin, but statistically different and superior for the case of the dinuclear complex. Cisplatin and oxaliplatin showed 41.4 and 40.8% inhibition, respectively, while the dinuclear complex presented 66.3%. The histopathological analysis demonstrated that the group treated with cisplatin showed more significant tissue damage, moderate hepatic steatosis, and nephritis. The livers, spleens, and kidneys of the animals treated with the dinuclear complex were within the normality range with no tissue lesions, and absence of metastasis.

Vanadium compounds are known to exert insulin-enhancing activity, normalize elevated blood glucose levels in diabetic subjects, and show significant activity in models of insulin resistance (IR). Faced with insulin resistance, the present work investigates the antidiabetic performance of a known oxidovanadium(IV)-based coordination compound—[VIVO(octd)]—and effects associated with glucocorticoid-induced insulin resistance in mice. The effects of [VIVO(octd)] were evaluated in a female Swiss mice model of insulin resistance induced by seven days of dexamethasone treatment in comparison with groups receiving metformin treatment. Biological assays such as hematological, TyG index, hepatic lipids, glycogen, oxidative stress in the liver, and oral glucose tolerance tests were evaluated. [VIVO(octd)] was characterized with 51V NMR, infrared spectroscopy (FTIR), electron paramagnetic resonance (EPR), electronic absorption spectroscopy, and mass spectrometry (ESI–FT–MS). The [VIVO(octd)] oral treatment (50 mg/kg) had an antioxidant effect, reducing 50% of fast blood glucose (p < 0.05) and 25% of the TyG index, which is used to estimate insulin resistance (p < 0.05), compared with the non-treated group. The oxidovanadium–sulfur compound is a promising antihyperglycemic therapeutic, including in cases aggravated by insulin resistance induced by glucocorticoid treatment.

The vanadium(V) complexes have been investigated as potential anticancer agents which makes it essential to evaluate their toxicity for safe use in the clinic. The large-scale synthesis and the acute oral toxicity in mice of the oxidovanadium(V) Schiff base catecholate complex, abbreviated as [VO(HSHED)dtb] containing a redox-active ligand with tridentate Schiff base (HSHED = N-(salicylideneaminato)-N’-(2-hydroxyethyl)-1,2-ethylenediamine) and dtb = 3,5-di-(t-butyl)catechol ligands were carried out. The body weight, food consumption, water intake as well biomarkers of liver and kidney toxicity of the [VO(HSHED)dtb] were compared to the precursors, sodium orthovanadate, and free ligand. The 10-fold scale-up synthesis of the oxidovanadium(V) complex resulting in the preparation of material in improved yield leading to 2–3 g (79%) material suitable for investigating the toxicity of vanadium complex. No evidence of toxicity was observed in animals when acutely exposed to a single dose of 300 mg/kg for 14 days. The toxicological results obtained with biochemical and hematological analyses did not show significant changes in kidney and liver parameters when compared with reference values. The low oral acute toxicity of the [VO(HSHED)dtb] is attributed to redox chemistry taking place under biological conditions combined with the hydrolytic stability of the oxidovanadium(V) complex. These results document the design of oxidovanadium(V) complexes that have low toxicity but still are antioxidant and anticancer agents.

This work presents the synthesis and spectroscopic study of new homotrinuclear (TRI) systems for photonics applications. The luminescence spectroscopy shows characteristics transitions of Eu(III) and Tb(III) ions. For the Gd(III) complexes, the triplets states were determined by phosphorescence measurement. The complexes’ coordination geometries were calculated using the Sparkle/AM1 model. For the europium systems, the Sparkle/AM1 geometries were used to calculate all details involved in the energy transfer process, and the theoretical quantum yields were determined. From an energy diagram, that estimates triplet levels, it was possible to understand some experimental phenomenon, such as weak luminescence for precursor complex (without heterocyclics ligands), and ligands emission in terbium complexes. Some of these observations can also be explained by the Jablonski diagrams that describe, based on theoretical calculations, all luminescent process. The synthesized complexes showed high values of quantum yield in ethanolic environment: 50% for EuTRIDipy, 26% EuTRITerpy, and 56% for EuTRIPhen complexes. [ABSTRACT FROM AUTHOR]

Traumatic amputations of the nasal tip are disfiguring injuries, which determine important social rejection, imposing additional suffering on the patient and those already caused by the wound and its functional limitations resulting from the trauma. Such defects represent a challenge for plastic surgeons, and several techniques can be adopted to treat this type of defect. This work shows three cases of traumatic amputation exclusively of the nasal tip with their respective treatments. They present a historical review and discussion of the different techniques used for nasal tip reconstruction, comparatively evaluating and emphasizing the technical evolution in plastic surgery armament.