Co-exposure effects of lead and TiO2 nanoparticles in primary kidney cell culture from the freshwater fish Hoplias malabaricus.

This study evaluated the effects of Lead (Pb) and titanium dioxide nanoparticles (TiO2 NPs) alone or in combination in anterior kidney macrophages of the freshwater fish Hoplias malabaricus, naïve or stimulated with 1 ng.mL-1 lipopolysaccharide (LPS). Pb (1 ×10-5 to 1 ×10-1 mg.mL-1) or TiO2 NPs (1.5 ×10-6 to 1.5 ×10-2 mg.mL-1) reduced cell viability despite LPS stimulation, especially Pb 10-1 mg.mL-1. In combination, lower concentrations of NPs intensified Pb-induced cell viability reduction while higher concentrations restored the cell viability independently of LPS stimulation. Basal and LPS- induced NO production was reduced by both TiO2 NPs and Pb isolated. The combination of both xenobiotics avoided this reduction of NO production by the isolated compounds at lower concentrations but the protective effect was lost as the concentrations increased. None xenobiotic increase DNA fragmentation. Therefore, at specific conditions, TiO2 NPs may have a protective effect over Pb toxicity, may also provide additional toxicity at higher concentrations.

First Italian birth after cryopreserved ovarian tissue transplantation in a patient affected by non-Hodgkin's lymphoma.

This case report describes the first Italian live birth obtained by cryopreserved ovarian tissue transplantation in a woman affected by non-Hodgkin's lymphoma. Before anticancer treatments, several fertility preservation options were proposed. At 29 years the patient underwent laparoscopy for ovarian tissue cryopreservation. After treatments she experienced premature ovarian failure (POF) and asked for cryopreserved ovarian tissue transplantation. Before transplantation, ovarian samples were analyzed to assess neoplastic contamination and tissue quality. Two subsequent ovarian tissue transplantations were performed 4 and 7 years after cryopreservation. The follicle-stimulating hormone and luteinizing hormone reduction, estradiol increase and first menstrual cycle appeared 2 months after the second transplantation. The woman conceived spontaneously 5 months after the second transplantation. After 39 weeks of uneventful gestation, a healthy male baby was born. Ovarian tissue cryopreservation, thawing and transplantation successfully restored ovarian function and fertility after tissue storage.

Mixtures of benzo(a)pyrene, dichlorodiphenyltrichloroethane and tributyltin are more toxic to neotropical fish Rhamdia quelen than isolated exposures.

The effects of benzo(a)pyrene (BaP), dichlorodiphenyltrichloroethane (DDT) and tributyltin (TBT) association were investigated through a multi-biomarker approach. Ten Rhamdia quelen fish per group were exposed through intraperitoneal injections either to BaP (0.3; 3 or 30 mg kg(-1)), DDT or TBT (0.03; 0.3 or 3 mg kg(-1)) or BaP/DDT, BaP/TBT, DDT/TBT or BaP/DDT/TBT on their lowest doses. The experiments were divided in acute (one dose, 5-day) and sub-chronic (3 doses, 15-day). Control groups received an equal volume of PBS or canola oil (1 ml kg(-1)). The three tested contaminants altered AChE activity in brain and muscle in similar ways; the mixtures antagonized the increase evoked by the contaminants alone. BaP and TBT increased GSH content and mixtures reduced it. GPx activity was increased by DDT and TBT in the 15-day experiment and reduced by the mixtures. BaP increased GST activity in sub-chronic experiment while TBT reduced it in the acute experiment. BaP/TBT increased GST activity compared to all groups; the other mixtures reduced it compared to BaP or DDT in the 5-day experiment. BaP, DDT and TBT increased δ-ALAd activity mainly in acute exposure; the mixtures also increased δ-ALAd compared to DDT or TBT in 5 and 15-day. BaP, TBT and BaP/DDT decreased LPO in the acute experiment. In the sub-chronic experiment DDT/TBT increased LPO when compared to TBT. None of the contaminants alone altered PCO, but all mixtures increased it compared to one or another contaminant. Contaminants isolated had a more acute effect in ALT plasma level; their lowest dose, which had no effect alone, in combination has led to an increase of this enzyme, especially after 15 days. DDT increased AST in the acute and sub-chronic experiments, while TBT did the same in the latter. DDT/TBT decreased AST opposing the effect of the contaminants alone in the 5-day experiment. Hepatic lesions index could be explained by a more acute effect of the contaminants alone or combined and by activation of cell defenses after the sub-chronic exposure. TBT increased melanomacrophages counting in the 5-day experiment and the mixtures increased it in the 5 and 15-day experiments. Overall, the majority of the biomarkers pointed to a more toxic effect when these contaminants were combined, leading to unexpected toxicities compared to individual exposure scenarios. These findings are relevant considering environmental exposure conditions, since organisms are often exposed to different combinations of contaminants.

Low concentrations of cylindrospermopsin induce increases of reactive oxygen species levels, metabolism and proliferation in human hepatoma cells (HepG2).

Human hepatoma cells (HepG2) were exposed to purified cylindrospermopsin (CYN), a potent toxicant for eukaryotic cells produced by several cyanobacteria. CYN was not toxic at concentrations up to 10 µgl(-1), leading to increased viability and metabolism in cells cultured with 10% fetal bovine serum (FBS). Reduction of FBS concentration to 2% and induction of cytochrome P450 (CYP) isoforms were performed in order to make xenobiotic-metabolizing capacity of HepG2 cells closest to that of 'normal' cells. HepG2 cells proliferated less after CYPs-induction, and this induction has lead to similar results of non-induced cells, except for few individual parameters such lipid peroxidation. Foremost, low concentrations of CYN (below or equal 10 µgl(-1)) have induced HepG2 cells proliferation and metabolism increase, which was not expected.

Modulatory effect of nano TiO2on Pb in Hoplias malabaricus trophically exposed.

This study investigated the hepatic and neural effects of TiO2 nanoparticle and Pb in Hoplias malabaricus trophically exposed. The alanine transaminase activity was altered at the high dose of exposed group to Pb and at the lowest doses of co-exposed groups. It may reflect the hepatic effects of TiO2 on Pb toxicity, but the aspatate transaminase activity was not altered. The decreased injury index observed at the highest dose of co-exposed group compared to TiO2 may be related to the increased energy demand and can explain the more pronounced toxic effects observed in this group. The liver authomethallography revealed the metals presence at high dose groups. Serotonin concentration increased at the Pb lowest dose and at the highest dose of co-exposed group compare to control. Most importantly, when associated the contaminants were able to interact and altered some biomarkers. However, further studies, about action mechanisms of this co-exposure are needed.

Using multibiomarker approach as a tool to improve the management plan for a Private Reserve of Natural Heritage (RPPN).

This study aimed to monitor an aquatic ecosystem during two different periods (dry and rainy season) on a protected area located inside a sugarcane farm, using the fish Astyanax sp. as bioindicator. An integrated approach was adopted by combining the responses of well-known biomarkers: acetylcholinesterase, lipid peroxidation (LPO), catalase (CAT), glutathione S-transferase (GST), micronucleus test, and liver histopathology. The activity of enzymes CAT and GST was increased after the rainy season. This can be explained mainly by the intensification of rain density, which drags substances into the streams, especially pesticides applied on agriculture. LPO and micronucleus test also suggested some effects of contamination in the surrounding area during this season. The results have supported a discussion about the effectiveness of protected areas in agricultural regions, emphasizing the biomonitoring as a tool for improving management plans in protected areas.

Insecticides biomarker responses on a freshwater fish Corydoras paleatus (Pisces: Callichthyidae).

This study was undertaken to investigate the effects of sublethal concentration of three different classes of insecticides (carbamate, organophosphate, and pyrethroid compounds) on the freshwater fish Corydoras paleatus. For this purpose, fish were exposed for 96 hours to commercial pesticides. Different biomarkers were analyzed as levels of lipid peroxidation (LPO), piscine micronucleus test, and enzymatic activities of catalase (CAT), glutathione S-transferase (GST), and acetylcholinesterase (AChE). The brain AChE was inhibited with carbaryl and methyl parathion, but no inhibition was observed with deltamethrin. The insecticides did not cause oxidative stress or genotoxic effects at the tested concentrations. Further studies are needed to elucidate the biotransformation of Corydoras paleatus insecticides and a possible resistance mechanism.

Sublethal effects of waterborne herbicides in tropical freshwater fish.

The study evaluated the sublethal effects of the herbicides glyphosate (Roundup) and diuron (Hexaron) and the mixture of them, used extremely in agriculture, through biomarkers in fish. The glutathione S-transferase activity increased (74%) and catalase activity decreased (37%) at the higher exposure concentration of Hexaron in comparison to the control group, suggesting an activation of this metabolism route. Membrane damage was observed at the higher exposure of Roundup and in the mixture group compared to the control group, which can be related to the nuclear alterations observed in these exposed groups. The cholinesterase activity was also inhibited (37%) in mixture group compared to the control group and no gill morphology damage was found. The results suggested a potential synergic effect in some analysed parameters.

Embryotoxicity and biotransformation responses in zebrafish exposed to water-soluble fraction of crude oil.

The toxic effects of water-soluble fraction (WSF) of crude oil (API27, Petrobras Campos Basin, Brazil) were evaluated during the early life stages of zebrafish, as well as its biotransformation in juvenile fish. Embryonic development was studied during 96 h. Reduced heartbeat rate, weak pigmentation, tail defects, and embryo mortality were observed for all of the tested concentrations of the WSF. Activities of the biotransformation enzymes were induced at the highest concentrations, showing that these enzymes played a role in its elimination. As shown in this study the crude oil WSF altered the normal embryonic development of fish.

Effects of Tribulus terrestris on endocrine sensitive organs in male and female Wistar rats.

AIM OF THE STUDY: Investigate the possible effects of Tribulus terrestris (TT) on endocrine sensitive organs in intact and castrated male rats as well as in a post-menopausal rat model using ovariectomized females. MATERIALS AND METHODS: Three different dose levels of TT (11, 42 and 110 mg/kg/day) were administered to castrated males for 7 days and to intact males and castrated females for 28 days. In addition to TT treatment, all experiments also included a group of rats treated with dehydroepiandrosterone (DHEA). In experiments using castrated males and females we also used testosterone and 17 alpha-ethynylestradiol, respectively, as positive controls for androgenicity and estrogenicity. RESULTS: Neither DHEA nor TT was able to stimulate androgen sensitive tissues like the prostate and seminal vesicle in both intact and castrated male rats. In addition, administration of TT to intact male rats for 28 days did not change serum testosterone levels as well as did not produce any quantitative change in the fecal excretion of androgenic metabolites. However, a slight increase in the number of homogenization-resistant spermatids was observed in rats treated with 11 mg/kg/day of TT extract. In ovariectomized females, TT did not produce any stimulatory effects in uterine and vaginal epithelia. CONCLUSIONS: Tribulus terrestris was not able to stimulate endocrine sensitive tissues such as the prostate, seminal vesicle, uterus and vagina in Wistar rats, indicating lack of androgenic and estrogenic activity in vivo. We also showed a positive effect of TT administration on rat sperm production, associated with unchanged levels of circulating androgens.

Resíduos de pesticidas em alimentos / Pesticide residues in food

Este trabalho teve como objetivos comparar os níveis de resíduos de pesticidas encontrados em alimentos investigados pelo Programa de Análise de Resíduos de Pesticidas em Alimentos da Agência Nacional de Vigilância Sanitária (PARA/ANVISA) e avaliar o possível risco tóxico da sua ingestão. Para tanto, foram comparados os dados dos relatórios do PARA de 2001 e 2003, quando 2647 amostras de nove culturas de hortaliças e frutas foram analisadas. Calculou-se o risco tóxico da ingestão desses resíduos pela população utilizando dados do limite máximo de resíduo para cada pesticida e do consumo alimentar. Também determinou-se o número de pesticidas que ultrapassaram o limite máximo de resíduos (LMR) permitido e pesticidas encontrados em culturas cujo uso não é permitido. Os resultados indicaram que não houve modificações significativas no número de resíduos encontrados nas duas avaliações efetuadas pelo PARA entre os anos de 2001 e 2003. Dentre as 2.647 amostras analisadas foram detectados resíduos de 2.256 pesticidas, sendo 68 por cento envolvendo o uso regular e 32 por cento o uso irregular (não-autorizado 89 por cento e uso acima do LMR 11 por cento). Dezenove pesticidas apresentaram risco tóxico para a população na avaliação do relatório de 2001 e 16 no relatório de 2003. Esses dados permitem concluir que alimentos com resíduos de pesticidas não deveriam apresentar risco para a população, exigindo melhoria na fiscalização do uso de pesticidas na agricultura.