Antioxidant action of glutathione and the ascorbic acid/glutathione pair in a model white wine

Glutathione was assessed individually, and in combination with ascorbic acid, for its ability to act as an antioxidant with respect to color development in an oxidizing model white wine system. Glutathione was utilized at concentrations normally found in wine (30 mg/L), as well as at concentrations 20-fold higher (860 mg/L), the latter to afford ascorbic acid (500 mg/L) to glutathione ratios of 1:1. The model wine systems were stored at 45 °C without sulfur dioxide and at saturated oxygen levels, thereby in conditions highly conducive to oxidation. Under these conditions the results demonstrated the higher concentration of glutathione could initially provide protection against oxidative coloration, but eventually induced color formation. In the period during which glutathione offered a protective effect, the production of xanthylium cation pigment precursors and o-quinone-derived phenolic compounds was limited. When glutathione induced coloration, polymeric pigments were formed, but these were different from those found in model wine solutions without glutathione. In the presence of ascorbic acid, high concentrations of glutathione were able to delay the decay in ascorbic acid and inhibit the reaction of ascorbic acid degradation products with the wine flavanol compound (+)-catechin. However, on depletion, the glutathione again induced the production of a range of different polymeric pigments. These results highlight new mechanisms through which glutathione can offer both protection and spoilage during the oxidative coloration of a model wine.     

Resistance screening essay of wine lactic acid bacteria on lysozyme: efficacy of lysozyme in unclarified grape musts

In wine making, the bacteriolytic activity of lysozyme has primarily been used to control the malolactic fermentation in wines. The use of lysozyme in musts before settling and the beginning of the alcoholic fermentation to inhibit the growth of lactic acid bacteria could be very beneficial. In a resistance test carried out in MT/b broth, lysozyme had greater antimicrobial activity toward Oenococcus oeni than Lactobacillus species. Several strains of wine bacteria belonging to Oenococcus proved sensitive to the bacteriolytic activity of lysozyme at low concentrations in both synthetic medium (MT/b) (50 mg/L), white must, or red must made with or without the skins (100 mg/L). Lactobacillus and Pediococcus strains survived at lysozyme concentrations of 200-500 and 500 mg/L, respectively, in MT/b and musts. Suspended solids in unclarified musts may strongly bind to lysozyme thereby causing its removal by filtration or centrifugation. One hour after lysozyme was added to musts, it was quantified by HPLC and found after centrifugation to be 40-50% and only 10% in musts made with or without the skins, respectively. Although appreciable amounts of lysozyme were bound to wine components, this did not appear to be a serious hindrance to lysozyme activity.     

Marine-Derived Compounds Targeting Topoisomerase II in Cancer Cells: A Review

Cancer affects more than 19 million people and is the second leading cause of death in the world. One of the principal strategies used in cancer therapy is the inhibition of topoisomerase II, involved in the survival of cells. Side effects and adverse reactions limit the use of topoisomerase II inhibitors; hence, research is focused on discovering novel compounds that can inhibit topoisomerase II and have a safer toxicological profile. Marine organisms are a source of secondary metabolites with different pharmacological properties including anticancer activity. The objective of this review is to present and discuss the pharmacological potential of marine-derived compounds whose antitumor activity is mediated by topoisomerase II inhibition. Several compounds derived from sponges, fungi, bacteria, ascidians, and other marine sources have been demonstrated to inhibit topoisomerase II. However, some studies only report docking interactions, whereas others do not fully explain the mechanisms of topoisomerase II inhibition. Further in vitro and in vivo studies are needed, as well as a careful toxicological profile evaluation with a focus on cancer cell selectivity.     

Palladio, an Index of Trace Element Alteration for the River Bacchiglione Based on Rhynchostegium riparioides Moss Bags

The concentration of Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Se, V and Zn was measured in the aquatic bryophyte Rhynchostegium riparioides after a 4-week transplantation at 83 stations in seven main watercourses and three smaller tributaries of the basin of the River Bacchiglione (NE Italy). The study, carried out in 9 months, aimed at establishing a database for statistical analyses to define a novel index of water quality, specifically calibrated for moss bags, and suitable for bio-monitoring purposes where autochthonous bryophytes are not available. The background level was estimated for each element, the ratio between sample and background concentration was adopted as measure of environmental alteration and a five-class interpretation scale was defined. The 73.8% of measured concentrations reflected a condition of naturality, 16.6% suspect of alteration, 7.6% sure alteration, 1.6% severe alteration and <0.5% extreme alteration. The condition of global environmental alteration (all contaminants) at each station was also defined. Forty-four stations presented absence or suspect of alteration, 39 sure alteration for one or more elements. Bivariate and multivariate analyses revealed (1) highly significant correlations (p?<?0.001) between the concentrations of Co–Mn, Sb–Zn, and Fe–V, depending on both natural and human factors, (2) chemical patterns leading to galvanic industries, metallurgy or urban sewages, in some case with a geographical distribution and (3) a gradient of environmental alteration from the Pre-Alps to the lowland. Coloured maps indicate both point sources and widespread environmental alteration, highlighting not only industrial–urban areas but also some apparently undisturbed sites.     

Seasonal Abundance of Particle-Phase Organic Pollutants in an Urban/Industrial Atmosphere

Polycyclic aromatic hydrocarbons (PAHs); their derivatives nitro, and methyl-PAHs; n-alkanes; and organic acids were investigated in the aerosol samples collected during two field campaigns conducted at three sampling stations in an industrialized city in southern Italy. The main sources affecting the atmosphere and its toxicity were investigated by means of the diagnostic ratios of: specific particulate-phase PAHs, marker compounds among nitro-PAHs, alkanes, and acids, the dominant wind direction, daily and seasonal abundance of carcinogenic organic substances. The potential importance of the non-regulated pollutants to assess the air quality was confirmed; in fact the carcinogenic organic compounds showed to have scarce correlation with particulate matter (PM) concentration. An exceptionally high variability of toxic compounds at a daily scale was due to meteorological condition causing periods of extremely high pollution levels.     

Conjunctival dacryops in two golden retrievers

Two 5-month-old golden retriever dogs were referred for the evaluation of a mass arising from the left ventrolateral conjunctiva of the lower eyelid. The masses were externally located, deemed to be cystic in nature, and were surgically removed, and in one case, 0.15 mL of clear fluid was collected. Cytological examination of the aspirated fluid revealed proteinaceous, basophilic amorphous material, and few epithelial cells with foamy cytoplasm and small nuclei. No micro-organisms were detected. Histological examination of the cysts showed a wall composed of single to double cell layers. The cells were cuboidal to flattened, nonciliated, lined with mild submucosal connective tissues and slight inflammation composed of lymphocytes, plasma cells, and rare macrophages. In some areas, lobules of acinar glandular tissue were observed. To the authors' knowledge, this is the first case report of conjunctival dacryops in dogs. The complete surgical removal of the cysts was curative in both cases.     

Mealworm (Tenebrio molitor) Diets Relative to the Energy Requirements of Small Mygalomorph Spiders (Paraphysa sp.)

This article describes the basic prey requirements of Paraphysa sp., a small mygalomorph spider from the central Andes. Paraphysa sp. can be maintained in captivity using mealworms (Tenebrio molitor) as its primary food source. During a period of 66 days the prey requirements (larvae/day) were calculated for weight maintenance and compared with findings of previously reported resting and active metabolic rates. The spiders in this study ate at frequencies between 0.18 and 0.59 larvae/day, with an average of 0.43 ± 0.14 larvae/day. From the regression line between frequency of feeding (larvae/day) and weight gain, we determined that 0.31 larvae/day were needed for a weight gain of 0. Thus, for the spiders to increase their weight, they would need to eat more than 1 larva every 3 days. This frequency yields a caloric intake of 0.193 kcal/d, or equivalently, a carbon dioxide production of 0.189 mL CO₂/g·h. The findings in this report are greater than the resting metabolic rate at 35°C, and they agree with the active metabolic requirements of this spider in the field.     

Thrombocytopenia and platelet activity in dogs experimentally infected with Rangelia vitalii

The aim of this study was to evaluate the platelet count, coagulation time and platelet activity in dogs experimentally infected with Rangelia vitalii during the acute phase of the disease. For this study, 12 young dogs (females) were used, separated in two groups. Group A (uninfected control) was composed by healthy dogs (n=5), and group B consisted of R. vitalii-infected animals (n=7). After being inoculated with R. vitalii-infected blood, animals were monitored by blood smear examinations, which showed intra-erythrocytic forms of the parasite five days post-inoculation (PI). Blood samples were collected on days 0, 10, 20 and 30 PI. The material collected was placed in tubes containing EDTA for quantification of platelets, citrate anticoagulant platelet aggregation, and measuring the clotting time. Right after blood collection on days 10 and 20 PI, dogs were anesthetized for collecting bone marrow samples. A significant reduction (P<0.01) of the number of platelets was observed in R. vitalii-infected blood, when compared with uninfected dogs on days 10 and 20 PI. Additionally, macro-platelets were observed only in infected dogs. Prothrombin time and activated partial thromboplastin time did not differ between infected and uninfected dogs. The megakaryocyte count increased (P<0.01) significantly in infected dogs when compared with uninfected ones on days 10 and 20 PI. Platelet aggregation decreased (P<0.01) significantly in infected dogs in comparison to the control on days 10 and 20 PI. Therefore, rangeliosis in dogs causes a severe thrombocytopenia during the acute phase of infection. This platelets reduction probably occurred due to splenic sequestration and/or immune-mediated thrombocytopenia.     

Effect of cooking on garlic (Allium sativum L.) antiplatelet activity and thiosulfinates content

The raw form of garlic and some of its preparations are widely recognized as antiplatelet agents that may contribute to the prevention of cardiovascular disease. Herein, we examined the in-vitro antiaggregatory activity (IVAA) of human blood platelets induced by extracts of garlic samples that were previously heated (in the form of crushed versus uncrushed cloves) using different cooking methods and intensities. The concentrations of allicin and pyruvate, two predictors of antiplatelet strength, were also monitored. Oven-heating at 200 degrees C or immersing in boiling water for 3 min or less did not affect the ability of garlic to inhibit platelet aggregation (as compared to raw garlic), whereas heating for 6 min completely suppressed IVAA in uncrushed, but not in previously crushed, samples. The latter samples had reduced, yet significant, antiplatelet activity. Prolonged incubation (more than 10 min) at these temperatures completely suppressed IVAA. Microwaved garlic had no effect on platelet aggregation. However, increasing the concentration of garlic juice in the aggregation reaction had a positive IVAA dose response in crushed, but not in uncrushed, microwaved samples. The addition of raw garlic juice to microwaved uncrushed garlic restored a full complement of antiplatelet activity that was completely lost without the garlic addition. Garlic-induced IVAA was always associated with allicin and pyruvate levels. Our results suggest that (1) allicin and thiosulfinates are responsible for the IVAA response, (2) crushing garlic before moderate cooking can reduce the loss of activity, and (3) the partial loss of antithrombotic effect in crushed-cooked garlic may be compensated by increasing the amount consumed.