Search

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.

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.

Polyoxovanadates (POV) are a subgroup of polyoxometalates (POM), which are nanosized clusters with reported biological activities. This manuscript describes the first toxicity evaluation of a mixed-valence polyoxovanadate, pentadecavanadate, (Me4N)6[V15O36Cl], abbreviated as V15. Cytotoxicity experiments using peripheral blood mononuclear cells (PBMC), larvae of Artemia salina Leach, and in vivo oral acute and repeated 28-day doses in mice was carried out. The LC50 values in PBMC cells and A. salina were 17.5 ± 5.8 μmol L−1, and 17.9 µg L−1, respectively, which indicates high cytotoxic activity. The toxicity in mice was not observed upon acute exposure in a single dose, however, the V15 repeated 28-day oral administration demonstrated high toxicity using 25 mg/kg, 50 mg/kg and, 300 mg/kg doses. The biochemical and hematological analyses during the 28-day administration of V15 showed significant alteration of the metabolic parameters related to the kidney and liver, suggesting moderate toxicity. The V15 toxicity was attributed to the oxidative stress and lipid peroxidation, once thiobarbituric acid (TBAR) levels significantly increased in both males and females treated with high doses of the POV and also in males treated with a lower dose of the POV. This is the first study reporting a treatment-related mortality in animals acutely administrated with a mixed-valence POV, contrasting with the well-known, less toxic decavanadate. These results document the toxicity of this mixed-valence POV, which may not be suitable for biomedical applications.

The focus of this paper is to study the asynchronous generator (generator of squirrel-cage induction), as an alternative distributed generation technology, in particular the driving of machines using methane gas from pig farms as their fuel. Pig farming has grown dramatically over recent years. This agro-industrial activity produces huge quantities of methane gas which is released into the atmosphere depleting the ozone layer, in addition to contributing to the greenhouse effect. When the subject is environmental concerns, methane is known to be many times more aggressive than carbon. Since the production of this gas is inherent to the pig farming industry, its effects can be mitigated by using it as fuel in an engine to drive an electricity generator, while adding value to the production chain.

The design of the capacitor bank to be placed with the squirrel cage induction generator, when operating with a direct connection to the distribution system, is performed from the value of the magnetization reactance of the machine. Based on the experimental procedures, the necessary reactive power is simulated according to the induction generator loading. Therefore, with the increase in generated active power, a larger portion of reactive is required. The simulation indicates the values of ideal capacitors. Thus, an analysis is made of which magnetization reactance factor is ideal for the capacitor bank design designated for the generator. The characteristic curve for capacitor bank sizing is related to the load torque loading depending on the active power generated. Thus, this work contributes to the analysis of the self-excitation curve of the three-phase induction generator that operates in parallel with the steady-state power distribution network. Obtaining the active power generated as a function of the absorbed reactive power required for induction generator magnetization can be found.

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. [ABSTRACT FROM AUTHOR]

This work presents a theoretical and experimental study of the self-excited three-phase induction generator in steady state, operating with a synchronous generator for use in isolated generation. Through the remoteness of many locations or because of the absence of an energy distribution network, difficulties exist in the supply of electric energy. The proposal contemplated herein can be applied in order to provide a well-adjusted voltage and reduce project costs in the expansion and implementation of isolated systems. That is, when taking into consideration acquisition costs of the asynchronous squirrel cage rotor machine in relation to the synchronous generator. The main contribution of this study is the making of the synchronous generator into a voltage regulator of the isolated system, in such a manner that the synchronous generator supplies the minimum of active power necessary, where a lower power generator is able to play the role of being the sole voltage regulator.

This paper presents an analysis of the oscillations caused by unbalanced loads in salient pole synchronous generators that operate in isolation under steady state. The oscillatory disturbances, arising from the second-order harmonics, may have or have the potential to cause electromechanical damage to the salient pole synchronous generator. In this paper, the goal is to identify and quantify the magnitude of the electromagnetic torque, which assumes an oscillatory form due to the current component from the negative sequence, caused by unbalanced currents. The self-same analysis was included for second-harmonic voltage oscillations in the qd0 domain, the currents induced on the damper windings together with the oscillation of the load angle and on the field current. These oscillations situated on the synchronous generator are analyzed for a degree of voltage unbalance close to 2% which is an acceptable value according to international regulations for power supply from distribution networks, and this same degree of tolerated voltage unbalance will be used herein for isolated synchronous generators.

Comorbid substance use disorder (SUD) in patients with schizophrenia (dual disorder, DD) is a frequent occurrence in the psychiatric clinical practice and is positively associated with poorer outcomes. Despite a very high co-prevalence, clinical guidelines for SUD and severe mental illnesses tend to give limited consideration to co-existing disorders regarding diagnosis and management. This article is the result of a meeting held in February 2023 to discuss common challenges and best clinical practice initiatives for patients with schizophrenia and DD in different treatment settings. The authors identified issues in the clinical approach to DD in schizophrenia spectrum disorders and suggested the most suitable management based on their experience as a group of experts, identifying possible improvement areas. In conclusion, the panel recommends that individuals with DD should be cared for in a single center. Pharmacologic treatment in individuals with DD needing both control of symptoms related to schizophrenia spectrum disorders and substance withdrawal should ideally be based on using a non-sedative antipsychotic with anti- craving activity. [ABSTRACT FROM AUTHOR]

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.