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An efficient method for constructing transgenic lettuce cultivars by Agrobacterium tumefaciens was described by Torres et al., 1993. In the present work, an improvement of the above procedure is described and applied to transform the cultivar Grand Rapids with a mutated P5CS gene. The major modifications were concerned with turning more practical the transformation and regeneration protocols. Also we tried to improve transformation steps by increasing injured area in explants and prolonging co-cultivation with Agrobacteria (in larger concentration). A more significant selective pressure was used against non-transformed plants and bacteria. In these work we were concerned to obtain T 1 and T 2 seeds. The P5CS gene codes for a ∆ 1 -pyrroline-5-carboxylate synthetase, a bifunctional enzyme that catalyzes two steps of proline biosynthesis in plants (Zhang et al., 1995;Peng et al., 1996), while the mutated gene is insensitive to feedback inhibition by proline. The potential benefit of this gene is to confer water stress resistance (drought, salt, cold) due to increased intracellular levels of proline that works like an osmoprotectant. In this work could obtain and characterize transgenic lettuce lineages which are resistant to freezing temperature.

In general, environmental responses at level of populations or communities are preceded by alterations at lower biological levels which can be efficiently detected by the analysis of biomarkers. We analyzed the oxidative biomarkers TBARS and Catalase in Aegla singularis, a freshwater crustacean highly sensitive to environmental changes. The objective was to address if are differences in these biomarkers related to the gender as well if they are influenced by seasonal or water physicochemical variables. The results showed differences in biomarkers profile related to the gender. In female crabs were not sensitive to seasonal variations throughout the study period. However, in males the biomarkers evaluated were higher in the winter as compared to remaining seasons and showed tendency of negative correlation with water temperature and pH. This study highlights that gender, seasonal variations and physicochemical variables can influence oxidative stress biomarkers in A. singularis. Female crabs probably are better suited as a model for biomarker application in environmental studies, because their insensibility to seasonal variations can facilitate the observations of responses related specifically to environmental disturbances.Keywords: Aegla, oxidative stress, biomarkers, benthic invertebrates, biomonitoring, catalase, TBARS. Caracterização de biomarcadores de estresse oxidativo em caranguejos anomuros de água doce ResumoEm geral, as respostas ambientais ao nível de populações ou comunidades são precedidas pelas alterações nos níveis biológicos inferiores que podem ser eficientemente detectados pela análise de biomarcadores. Neste trabalho, foram analisados os biomarcadores oxidativos TBARS e Catalase em Aegla singularis, um crustáceo de água doce altamente sensível às mudanças ambientais. O objetivo foi investigar se há diferenças nestes biomarcadores relacionados com o gênero, bem como se eles são influenciados por parâmetros sazonais ou físico-químicos. Os resultados mostraram diferenças no perfil de biomarcadores relacionados com o gênero. Caranguejos fêmeas não foram sensíveis a variações sazonais ao longo do período de estudo. Nos machos, os biomarcadores avaliadas apresentaram níveis mais altos no inverno, em comparação com as demais estações e mostraram uma tendência de correlação negativa com a temperatura e pH da água. Este estudo destaca que o sexo, variações sazonais e variáveis físico-químicas podem influenciar os biomarcadores de estresse oxidativo em A. singularis. As fêmeas de A. singularis provavelmente são mais adequadas como um modelo para aplicação destes biomarcadores em estudos ambientais, uma vez que sua insensibilidade às variações sazonais podem facilitar as observações das respostas relacionadas especificamente com perturbações ambientais.Palavras-chave: Aegla, estresse oxidativo, biomarcadores, invertebrados bentônicos, biomonitoramento, catalase, TBARS.

The intensity of exercise determines the metabolic pathway and the energetic substrate that is spent. Our study sought to identify the effects of different intensities of swimming on myocardial oxidative status and the blood lipid profile. Eighty Wistar rats (male and female) submitted to different intensities of a swimming regimen (low, LS; moderate, MS; or high, HS) for 16 weeks. Samples of blood and myocardium from the left ventricle were collected to determine lipid profiles and oxidative status. Reactive oxygen species (ROS) and antioxidant capacity against peroxyl radicals (ACAP), lipid profiles and lipid peroxidation was analyzed. ROS levels and ACAP were higher in male rats than in female rats overall (p<0.05). However, ACAP in the myocardium was significantly elevated in LS female rats compared to the MS and HS female rats, which had a significantly lower ACAP compared to all other groups. LS and MS training in both sexes and HS training (in females) led to significant decreases in the heart’s lipid peroxidation. Amelioration of the lipid profile and reduction in oxidative damage contributed to a physiological state that benefits cardiovascular function in exercised animals. The results show that low and moderate intensity exercise promotes beneficial adaptations.

ABSTRACT. Streams in urban areas are strongly impacted by the input of organic matter and metals, for instance copper (Cu) and zinc (Zn). These metals are essential for the aquatic biota, but when absorbed in excess they are toxic. In Chiro nomidae larvae, the deleterious effects of heavy metals can be ascertained by analyzing the morphological deformities of the larval mentum, a structure of the oral cavity. In this study, we evaluated I) the bioavailability of Cu and Zn in urban stream sediments and II) the relationship between Cu and Zn concentrations and the incidence of deformities in the mentum of Chironomus larvae. Chironomid flies were collected from four locations in two streams at an urban area in southern Brazil.They were identified and the incidence of deformities in the mentum was quantified. Sediment samples were collected at the same locations where larvae were collected, to quantify the bioavailable fractions of Cu and Zn. The concentrations of Cu in the sediment were similar between the collection sites. However, Zn concentrations varied among sites, being greater in the stretch directly influenced by the input of the organic waste. In total, 2,895 Chironomid larvae were collected. The incidence of deformities in the mentum was above 30% and was correlated with the concentrations of Cu (r = 0.68) and Zn (r = 0.87). This correlation indicates that the municipal waste that is thrown into the city's streams has influenced the occurrence of deformities.

Objectives A microemulsion‐based delivery system was designed to improve vitamin E (VE) properties, and its antinociceptive, antioxidant, antidepressant‐ and anxiolytic‐like activities in mice were evaluated. Methods Male Swiss mice received, by intragastric route, canola oil (20 ml/kg), blank microemulsion (B‐ME) (20 ml/kg), VE free (VE‐F) (200 mg/kg) or VE microemulsion (VE‐ME) (200 mg/kg). In acute treatment, a single dose of treatments was administrated and 30 min after behavioural tests were performed. In the subchronic treatment, mice received such treatments, once a day, for 8 days. On the eighth day, behavioural tests were performed. Key findings In the subchronic treatment, VE‐ME increased entries and spent time in the open arms in the elevated plus‐maze test and decreased the immobility time in the tail suspension test, but no change was found after acute treatment. Acute and subchronic treatments with VE‐ME increased response latency to thermal stimulus in the hot‐plate test. VE‐ME decreased the thiobarbituric acid reactive species levels in the acute and subchronic protocols. Additionally, in subchronic treatment, VE‐ME increased renal catalase activity, but VE‐F reduced its activity. Conclusions Vitamin E‐microemulsions showed antioxidant, antinociceptive, antidepressant‐ and anxiolytic‐like actions; thus, ME‐based delivery improved pharmacological properties of VE.

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