Biochemical and toxicological effects of organic (herbicide Primextra® Gold TZ) and inorganic (copper) compounds on zooplankton and phytoplankton species

In Europe, mainly in the Mediterranean region, an intensive usage of pesticides was recorded during the past 30 years. According to information from agricultural cooperatives of the Mondego valley (Figueira da Foz, Portugal), Primextra® Gold TZ is the most used herbicide in corn crop fields and one of the 20 best-selling herbicides in Portugal. Copper is mainly used in pesticide formulations. This study aims to determine the ecotoxicological and biochemical (namely fatty acid profiles) effects of the herbicide Primextra® Gold TZ and the metal copper on marine plankton. The organisms used in this study are three planktonic species: the marine diatom Thalassiosira weissflogii, the estuarine copepod Acartia tonsa and nauplii of the marine brine shrimp Artemia franciscana. Fatty acids (FAs) are one of the most important molecules transferred across the plant-animal interface in aquatic food webs and can be used as good indicators of stress. The conducted lab incubations show that T. weissflogii is the most sensitive species to the herbicide followed by A. tonsa (EC50 =0;0.0078 mg/L and EC50 =0;0.925 mg/L, respectively), whereas the copepod was the most sensitive species to the metal followed by T. weissflogii (EC50 =0.234 mg/L and EC50 =0.383 mg/L, respectively). A. franciscana was the most tolerant organism both to the herbicide and to the metal (EC50 =20.35 mg/L and EC50 = 18.93 mg/L, respectively). Changes in the FA profiles of primary producer and primary consumers were observed, with the increase of saturated FA and decrease of unsaturated FA contents, especially of highly unsaturated FAs that can be obtained mainly from food and therefore are referred to as ‘essential FA’. The study suggests that discharges of Primextra® Gold TZ or other pesticides mainly composed by copper may be a threat to plankton populations causing changes in the FA contents and thus in their nutritive value, with severe repercussions for higher trophic levels and thus the entire food web

Validation of the rat model of prostate cancer: correlating seminal vesicle lesions with dorsolateral prostate lesions

Background/aim: Lesions in the seminal vesicle are described in the most used protocols for prostate cancer (PCa) induction. This study aimed to characterize the lesions of seminal vesicles associated with a protocol of PCa induction in rats to contribute to better characterization of this model. Materials and methods: Forty-five male Wistar Unilever rats were randomly divided into two control groups: CONT1 (n=10) and CONT2 (n=10); and two PCa-induced groups: IND1 (n=10) and IND2 (n=15), sacrificed at 35 and 61 weeks, respectively. Animals from the induced groups were exposed to a multistep protocol for PCa induction. Animals, seminal vesicles and dorsolateral prostate were weighed. Seminal vesicles and dorsolateral prostate were submitted to histopathological and immunohistochemical analysis. Results: Animals in which PCa was induced had a lower mean body weight when compared with the control animals (p<0.05). The relative mean seminal vesicle weight was higher in groups with PCa when compared with control groups (p<0.05). Although the differences were not statistically significant, animals from the IND2 group developed more lesions than animals from the IND1 and CONT2 groups. It is worth noting that the animals from group IND2 developed papillary adenomas and carcinomas in situ, which were not observed in any other group. Similar to observations in seminal vesicles, animals from group IND2 developed more dorsolateral prostate lesions than animals from the IND1 group (p<0.05). Conclusion: We observed that the longer the exposure to testosterone was, the greater was the incidence of preneoplastic and neoplastic lesions in both the seminal vesicle and the prostate, suggesting that testosterone exposure affects the spectrum of developed lesions

Castanea sativa mill. flowers as potential chemopreventive agent against rat prostate cancer model

Introduction: Prostate cancer is one of the most common cancer among men, having a huge impact in their health [1]. This work aimed to evaluate the influence of a decoction extract obtained from C. sativa flowers (CF) on chemically and hormonally induced rat prostate cancer animal model. Material & Methods: All the animal experiments were approved by the Institutional Animals Ethics Committee and by Portuguese national authorities (DGAV no 021326). Forty male Wistar Unilever rats were randomly divided into four groups: control group (n=10), induced group (n=15), CF control group (n=5) and CF induced group (n=10). Animals from induced groups received a multistep induction protocol, which consisted of sequential administration of flutamide, testosterone propionate, the carcinogenic agent MNU and crystalline testosterone. The CF extract, rich in ellagitannins especially trigalloy-HHDP- glucose, was administered in the drinking water (3 mg/animal/day) for 49 weeks. Animals were sacrificed at 61 weeks of age and organs were collected, weighed and processed for light microscopy. Data were analysed using SPSS and GraphPad Prism software. Results: There were no significant differences in relative mean liver weight among groups exposed and not exposed to the CF extract and no animals developed severe hepatic changes. Animals from CF induced group developed less prostatic intraepithelial neoplasia than induced group. Also, animals exposed to the CF extract did not present areas of inflammation of the dorsolateral prostate lobe greater than 50% unlike the groups not exposed (p<0.05). The administration of CF in induced animals was able to decrease the activity of CAT and GST by 36% and 20%, respectively (p<0.05). Conclusions: These results suggest that CF extract was well tolerate by the animals and did not cause severe hepatic and renal toxicity. C. sativa flowers extract may be used as chemopreventive agent against prostate cancer and seems to have an antioxidant role

Brain activation of the defensive and appetitive survival systems in obsessive compulsive disorder

Several studies have shown that basic emotions are responsible for a significant enhancement of early visual processes and increased activation in visual processing brain regions. It may be possible that the cognitive uncertainty and repeated behavioral checking evident in Obsessive Compulsive Disorder (OCD) is due to the existence of abnormalities in basic survival circuits, particularly those associated with the visual processing of the physical characteristics of emotional-laden stimuli. The objective of the present study was to test if patients with OCD show evidence of altered basic survival circuits, particularly those associated with the visual processing of the physical characteristics of emotional stimuli. Fifteen patients with OCD and 12 healthy controls underwent functional magnetic resonance imaging acquisition while being exposed to emotional pictures, with different levels of arousal, intended to trigger the defensive and appetitive basic survival circuits. Overall, the present results seem to indicate dissociation in the activity of the defense and appetitive survival systems in OCD. Results suggest that the clinical group reacts to basic threat with a strong activation of the defensive system mobilizing widespread brain networks (i.e., frontal, temporal, occipital-parietal, and subcortical nucleus) and blocking the activation of the appetitive system when facing positive emotional triggers from the initial stages of visual processing (i.e., superior occipital gyrus)

Ulcerogenic Helicobacter pylori Strains Isolated from Children: A Contribution to Get Insight into the Virulence of the Bacteria

Infection with Helicobacter pylori is the major cause for the development of peptic ulcer disease (PUD). In children, with no other etiology for the disease, this rare event occurs shortly after infection. In these young patients, habits of smoking, diet, consumption of alcohol and non-steroid anti-inflammatory drugs and stress, in addition to the genetic susceptibility of the patient, represent a minor influence. Accordingly, the virulence of the implicated H. pylori strain should play a crucial role in the development of PUD. Corroborating this, our in vitro infection assays comparing a pool of five H. pylori strains isolated from children with PUD to a pool of five other pediatric clinical isolates associated with non-ulcer dyspepsia (NUD) showed the greater ability of PUD strains to induce a marked decrease in the viability of gastric cells and to cause severe damage in the cells cytoskeleton as well as an impairment in the production/secretion of mucins. To uncover virulence features, we compared the proteome of these two groups of H. pylori strains. Two-dimensional gel electrophoresis followed by mass-spectrometry allowed us to detect 27 differentially expressed proteins between them. In addition to the presence of genes encoding well established virulence factors, namely cagA, vacAs1, oipA “on” status, homB and jhp562 genes, the pediatric ulcerogenic strains shared a proteome profile characterized by changes in the abundance of: motility-associated proteins, accounting for higher motility; antioxidant proteins, which may confer increased resistance to inflammation; and enzymes involved in key steps in the metabolism of glucose, amino acids and urea, which may be advantageous to face fluctuations of nutrients. In conclusion, the enhanced virulence of the pediatric ulcerogenic H. pylori strains may result from a synergy between their natural ability to better adapt to the hostile human stomach and the expression of the established virulence factors