Assessment of total (anti)oxidant status in goat kids

The redox potential of goat serum was assessed by different spectrophotometric assays. Among them, three methods are commonly applied for the evaluation of the oxidative (reactive oxygen metabolites, ROMs, and total oxidant status, TOS) and nitrosative (NO q metabolites, NOx ) stress, and four methods for the evaluation of the antioxidant status: the total antioxidant capacity (TAC) based on the ferric reducing ability of plasma (FRAP), the total antioxidant activity (TAA) based on the reduction of the coloured ABTS•+radical cation, the free radical scavenging activity (FRSA) based on the reduction of the purple DPPH•, and the total thiol levels (TTLs) based on their interaction with DTNB to form a highly coloured anion. Besides, myeloperoxidase (MPO) and ceruloplasmin oxidase (CP) activities were also assessed. Except for TAA, analytical data showed a great inter-individual variation for both oxidant and antioxidant assays. ROMs were strongly correlated with CP, while TOS with MPO and TAC. Furthermore, a tendency between TOS and FRSA was shown. NOx was correlated with TAC and TAA, and a tendency with TOS was shown. No correlations appeared among the antioxidant assays, even if a tendency between TAC and TAA was evidenced, but TAC was correlated with MPO activity. The observed correlation between ROMs and CP is discussed as a possible analytical interference. The absence of correlation among the antioxidant biomarkers suggests the simultaneous use of a panel of tests to verify any changes in the redox balance, mainly in livestock in which reference values for each biomarker are lacking

Ceruloplasmin Interferes with the Assessment of Blood Lipid Hydroperoxide Content in Small Ruminants

Simple and inexpensive analytical methods for assessing redox balance in biological matrixes are widely used in animal and human diagnostics. Two of them, reactive oxygen metabolites (ROMs) and total oxidant status (TOS), evaluate the lipid hydroperoxide (LOOH) content of the sample and are based on iron-mediated mechanisms. However, these tests provide uncorrelated results. In this study, we compared these two tests in the blood serum of goat kids and lambs, together with an evaluation of ceruloplasmin (CP) oxidase activity. No significant correlation was found between ROMs and TOS, or between TOS and CP oxidase activity, in either species. Conversely, ROMs and CP oxidase activity were highly correlated in both kid and lamb samples (p < 0.001). A significant progressive reduction in the analytical signal in the ROMs assay was observed when sodium azide, an effective CP inhibitor, was added to the samples before the assay (p < 0.001). This decrease was related to sodium azide concentration (p < 0.01) and was not found when sodium azide was added at the same concentrations in the TOS assay. These findings suggest that ROMs, unlike TOS, may be affected by CP, which interferes with LOOH detection in blood samples

ALP-Based Biosensors Employing Electrodes Modified with Carbon Nanomaterials for Pesticides Detection

Due to the growing presence of pesticides in the environment and in food, the concern of their impact on human health is increasing. Therefore, the development of fast and reliable detection methods is needed. Enzymatic inhibition-based biosensors represent a good alternative for replacing the more complicated and time-consuming traditional methods (chromatography, spectrophotometry, etc.). This paper describes the development of an electrochemical biosensor exploiting alkaline phosphatase as the biological recognition element and a chemically modified glassy carbon electrode as the transducer. The biosensor was prepared modifying the GCE surface by a mixture of Multi-Walled-Carbon-Nanotubes (MWCNTs) and Electrochemically-Reduced-Graphene-Oxide (ERGO) followed by the immobilization of the enzyme by cross-linking with bovine serum albumin and glutaraldehyde. The inhibition of the biosensor response caused by pesticides was established using 2-phospho-L-ascorbic acid as the enzymatic substrate, whose dephosphorylation reaction produces ascorbic acid (AA). The MWCNTs/ERGO mixture shows a synergic effect in terms of increased sensitivity and decreased overpotential for AA oxidation. The response of the biosensor to the herbicide 2,4-dichloro-phenoxy-acetic-acid was evaluated and resulted in the concentration range 0.04-24 nM, with a limit of the detection of 16 pM. The determination of other pesticides was also achieved. The re-usability of the electrode was demonstrated by performing a washing procedure

Delay Management in Public Transportation: Service Regularity Issues and Crew Re-scheduling

In this paper, we propose a decision support tool to assist a local public transportation company in tackling service delays and small disruptions. We discuss different ways to assess and improve the regularity of the service, and we propose a simulation based optimization system that can be effectively used in a real-time environment taking into account both vehicle and driver shifts. In particular, we describe a tabu-search procedure for the online vehicle scheduling optimizing the regularity of the service and a column generation approach for the consequential crew re-scheduling minimizing the driver extra-time. As a case study, we analyze the management of urban surface lines of Azienda Trasporti Milanese (ATM) of Milan. In the last part of the paper we report a detailed analysis of the experimental phase showing the effectiveness of the proposed approach

Plantas do Cerrado Brasileiro Como Possíveis Agentes Moluscicidas

Diversas doenças parasitárias que atingem grande parte da população humana e animal possuem moluscos como hospedeiros intermediários. Doenças como fasciolose, que atinge bovinos, ovinos e caprinos, gerando prejuízos para a indústria alimentícia. Essa doença possui o caramujo do gênero Lymnaea, como hospedeiro intermediário no seu ciclo evolutivo. Por causar grandes perdas econômicas é uma doença de elevada importância para a área de medicina veterinária. As drogas usadas para o tratamento dessa parasitose reduzem sua morbidade, porém não controlam a transmissão. A utilização de agentes moluscicidas como forma de controle da multiplicação e propagação dos caramujos representa uma estratégia eficiente e a busca por novos compostos químicos tem sido estudada. Os moluscicidas naturais são produtos mais barato, seguros, biodegradáveis e de fácil acesso localmente. Neste estudo foram utilizados extratos hidroalcoólicos de plantas originárias do cerrado brasileiro, sendo elas Neea theifera Oerst., Davilla elliptica, Davilla nitida e Miconia cabucu Hoehne, para serem testados contra moluscos do gênero Lymnaea e assim, verificarmos suas possíveis ações moluscicidas. Os extratos hidroalcoólicos de D. nitida e D. elliptica apresentam atividade moluscicida contra a espécie L. columella, sendo que D. elliptica apresentou resultados mais promissores, desencadeando efeitos tanto moluscicidas como ovicidas, nos testes realizados

Fluorescence Spectroscopy for the Diagnosis of Endometritis in the Mare

By exploiting the PMN property to produce high quantities of oxygen peroxide to neutralize pathogens, the oxygen peroxide content of uterine cells was measured to diagnose endometritis. After preliminary in vitro studies in which endometrial cells from slaughtered mares were mixed with leukocytes from peripheral blood, endometrial samples were collected by uterine flushing from mares before insemination. Staining endometrial cells with H2DCF-DA was combined with hydroethidine to normalize the fluorescence intensity with the cellular content of the sample. Stained cell smears were assumed as the gold standard of endometritis, and based on this assay, the samples were considered positive (C+) and negative (C-) for endometritis. The amount and the turbidity of fluid recovered by uterine flushing were significantly (p < 0.01) higher in C+ than in C-. Moreover, the oxygen peroxide content of the endometrial cells was significantly higher in the C+ than in the C- group (6.31 ± 1.92 vs. 3.12 ± 1.26, p = 0.001). Using the value of 4.4 as the cutoff level of this fluorescence cytology assay, it was found that only one C- sample exceeded the cutoff level (false positives = 7.7%) while three C+ samples showed values below the cutoff level (false negative = 11.5%)

Evaluation of the Antioxidant Capacity of Fruit Juices by Two Original Analytical Methods

Two analytical methods previously developed by our groups were employed to estimate the antioxidant capacity of commercial fruit juices. The electrochemical method, which measures the scavenging activity of antioxidants towards OH radicals generated by both hydrogen peroxide photolysis and Fenton’s reaction, is based on the recovery of the cyclic voltametric response of the redox probe Ru(NH3)63+ at a Glassy Carbon electrode modified with a thin film of an insulating polyphenol, in the presence of compounds with antioxidant properties. The values of the antioxidant capacity of the fruit juices are expressed as vitamin C equivalents/L. The chromatographic method is based on the generation of OH radicals via Fenton’s reaction in order to test the inhibition of their formation in the presence of antioxidant compounds by monitoring salicylate aromatic hydroxylation derivatives as markers of •OH production, by means of HPLC coupled to coulometric detection. The results are expressed as the percentage of inhibition of •OH production in the presence of the tested juice compared to the control sample. When OH radicals are produced by Fenton’s reaction, the antioxidant capacity of the juices, estimated by both methods, displays an analogous trend, confirming that they can be considered an alternative for measuring the ability of antioxidants to block OH radical formation

Photoredox Allylation Reactions Mediated by Bismuth in Aqueous Conditions

Organometallic allylic reagents are widely used in the construction of C−C bonds by Barbier-type reactions. In this communication, we have described a photoredox Barbier allylation of aldehydes mediated by bismuth, in absence of other metals as co-reductants. Mild reaction conditions, tolerance of oxygen, and use of aqueous solvent make this photoredox methodology attractive for green and sustainable synthesis of homoallylic alcohols