Orientador: Noeme Sousa Rocha / Banca: Julio Lopes Sequeira / Banca: Alaor Aparecido Almeida / Banca: Maria Aparecida Custódio Domingues / Banca: Vera Maria Villamil Martins / Resumo: Dos tumores diagnosticados nas cadelas as neoplasias mamárias apresentam a maior incidência. Essas neoplasias podem ser influenciadas por fatores internos e externos como os contaminantes ambientais. Apesar das evidências da toxicidade dos piretróides, seu potencial cancerígeno ainda não foi suficientemente esclarecido, havendo a necessidade de investigação de sua participação no câncer de mama. Este estudo teve por objetivo investigar possíveis relações entre resíduos de piretróides e carcinoma de mama espontâneo de cadelas correlacionando-os com o grau de agressividade da neoplasia. Foram selecionadas 50 cadelas divididas em cinco grupos com 10 animais cada. O Grupo Controle foi formado por cadelas que apresentavam diagnóstico negativo para neoplasia em mama; os grupos Luminal A, Luminal B, Superexpressão de HER-2 e Basal foram formados por cadelas que apresentaram carcinoma em mama classificado pela imunoistoquimica como Luminal A, Luminal B, Superexpressão de HER-2 e Basal, respectivamente. O grau de agressividade dos carcinomas foi avaliado por imunoistoquímica mediante a expressão de HER-2, p63 e receptor de Estrógeno. A determinação da concentração de resíduos piretróides aletrina, cipermetrina, deltametrina e tetrametrina da mama e do tecido adiposo adjacente à mama foi realizada por Cromatografia Líquida de Alta Eficiência. A intensidade de dano no DNA foi avaliada pelo Teste do Cometa. Das 50 cadelas, seis apresentaram resíduos de um ou mais piretróides nas amostras das mamas avaliadas e 10 apresentaram resíduos desse inseticida nas amostras de tecido adiposo. O piretróide mais frequente foi a deltametrina. A distribuição de cada resíduo investigado entre os grupos avaliados e entre as amostras de mama e de tecido adiposo em um mesmo animal foi heterogênea. Não há evidência estatística de que os piretróides estejam envolvidos na ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: From all tumors that are diagnosed in female dog, the mammary neoplasia is the one that has the highest incidence. This sort of neoplasia may be influenced by both internal and external factors. Good examples of external factors are the environment contaminants. In spite of knowing the evidences of pyrethroid toxicity, it is not sufficiently clarified yet its cancer potential, thus leaving room for further investigation regarding its participation in the mammary tumor formation. This study aims at investigating not only the possible relationships between pyrethroid residue and spontaneous mammary carcinoma in female dog, but also correlating the degree of aggressiveness of such neoplasia. 50 female dog were selected and divided into five groups containing 10 animals each. Control group contained female dog that presented negative results for mammary neoplasia; female dog that presented mammary carcinoma and were immunohistochemically diagnosed as Luminal A, Luminal B, HER-2 Super-expression and Basal, were divided into groups bearing their respective tumor name. Carcinoma aggressiveness degree was immunohistochemically assessed concerning its expression of HER-2, p63 and Estrogen receptor. In order to define pyrethroid residue concentration for alethrin, cypermethrin, deltamethrin, and tetramethrin on mammary and mammary adjacent adipose tissue it was performed High-Performance Liquid Chromatography. The intensity of DNA damage was assessed via Comet Assay. From the 50 female dog, six have presented residue of one or more pyrethroids in mammary samples, and 10 presented residue of this insecticide in adipose tissue samples. The most frequently found pyrethroid residue was deltamethrin. Residue distribution among groups, and both mammary and adipose tissue of the same individual presented heterogeneous results. There is no statistical evidence showing that pyrethroids may be involved in ... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2014-06-11T19:31:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-13Bitstream added on 2014-06-13T20:22:03Z : No. of bitstreams: 1 colodel_mm_dr_botfmvz.pdf: 2872859 bytes, checksum: e38e46863de7b5075ae5aa7ad99cbf0f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dos tumores diagnosticados nas cadelas as neoplasias mamárias apresentam a maior incidência. Essas neoplasias podem ser influenciadas por fatores internos e externos como os contaminantes ambientais. Apesar das evidências da toxicidade dos piretróides, seu potencial cancerígeno ainda não foi suficientemente esclarecido, havendo a necessidade de investigação de sua participação no câncer de mama. Este estudo teve por objetivo investigar possíveis relações entre resíduos de piretróides e carcinoma de mama espontâneo de cadelas correlacionando-os com o grau de agressividade da neoplasia. Foram selecionadas 50 cadelas divididas em cinco grupos com 10 animais cada. O Grupo Controle foi formado por cadelas que apresentavam diagnóstico negativo para neoplasia em mama; os grupos Luminal A, Luminal B, Superexpressão de HER-2 e Basal foram formados por cadelas que apresentaram carcinoma em mama classificado pela imunoistoquimica como Luminal A, Luminal B, Superexpressão de HER-2 e Basal, respectivamente. O grau de agressividade dos carcinomas foi avaliado por imunoistoquímica mediante a expressão de HER-2, p63 e receptor de Estrógeno. A determinação da concentração de resíduos piretróides aletrina, cipermetrina, deltametrina e tetrametrina da mama e do tecido adiposo adjacente à mama foi realizada por Cromatografia Líquida de Alta Eficiência. A intensidade de dano no DNA foi avaliada pelo Teste do Cometa. Das 50 cadelas, seis apresentaram resíduos de um ou mais piretróides nas amostras das mamas avaliadas e 10 apresentaram resíduos desse inseticida nas amostras de tecido adiposo. O piretróide mais frequente foi a deltametrina. A distribuição de cada resíduo investigado entre os grupos avaliados e entre as amostras de mama e de tecido adiposo em um mesmo animal foi heterogênea. Não há evidência estatística de que os piretróides estejam envolvidos na... / From all tumors that are diagnosed in female dog, the mammary neoplasia is the one that has the highest incidence. This sort of neoplasia may be influenced by both internal and external factors. Good examples of external factors are the environment contaminants. In spite of knowing the evidences of pyrethroid toxicity, it is not sufficiently clarified yet its cancer potential, thus leaving room for further investigation regarding its participation in the mammary tumor formation. This study aims at investigating not only the possible relationships between pyrethroid residue and spontaneous mammary carcinoma in female dog, but also correlating the degree of aggressiveness of such neoplasia. 50 female dog were selected and divided into five groups containing 10 animals each. Control group contained female dog that presented negative results for mammary neoplasia; female dog that presented mammary carcinoma and were immunohistochemically diagnosed as Luminal A, Luminal B, HER-2 Super-expression and Basal, were divided into groups bearing their respective tumor name. Carcinoma aggressiveness degree was immunohistochemically assessed concerning its expression of HER-2, p63 and Estrogen receptor. In order to define pyrethroid residue concentration for alethrin, cypermethrin, deltamethrin, and tetramethrin on mammary and mammary adjacent adipose tissue it was performed High-Performance Liquid Chromatography. The intensity of DNA damage was assessed via Comet Assay. From the 50 female dog, six have presented residue of one or more pyrethroids in mammary samples, and 10 presented residue of this insecticide in adipose tissue samples. The most frequently found pyrethroid residue was deltamethrin. Residue distribution among groups, and both mammary and adipose tissue of the same individual presented heterogeneous results. There is no statistical evidence showing that pyrethroids may be involved in ... (Complete abstract click electronic access below)

Pyrethroid insecticides applied on crops and in urban areas are being found in aquatic ecosystems due to natural processes, such as run-off. Although highly toxic to invertebrates and fish, populations of Hyalella azteca have become resistant to some of these compounds, which pose risks to not only their populations, but higher trophic level populations via bioaccumulation (in this thesis, the Inland silverside (Menidia beryllina)). Concurrently, the impact of global climate change (GCC) is impacting environmental water parameters, such as temperature and salinity. The objective of this thesis was to analyze the relationship between varying water parameters due to GCC on the fate of permethrin (a type of pyrethroid) in resistant H. azteca (by measuring toxicokinetic rates) and in M. beryllina (by measuring bioaccumulation after consuming permethrin-dosed resistant H. azteca). Permethrin bioconcentration testing used two distinct populations (Mosher Slough and Escondido Creek) of pyrethroid-resistant H. azteca and showed that temperature and salinity affected toxicokinetic rates. Statistical differences in metabolite formation rates (km) across temperatures were found between and within populations. Salinity also exhibited statistical differences in the elimination of parent compound (kep). No statistically significant differences in uptake rates (ku) were found for either population. In the M. beryllina testing, the ability for the fish to bioaccumulate permethrin via a dietary route of exposure was confirmed, contradicting previous findings. Statistically significant bioaccumulation was found across salinities, whereas no statistically significant temperature effects were observed. With the predicted increased use of pyrethroids over the course of the next century, the emergence of resistant populations of H. azteca may increase, simultaneously increasing the risk for bioaccumulation by higher trophic species. With rates of biotransformation in H. azteca affected by changing water parameters due to GCC change, the ratio of parent and metabolite compound transferred to fish will also be altered. Pyrethroid metabolites in fish act as endocrine disruptors rather than inhibit nerve function like the parent compound, which can significantly affect fish development. Overall, this thesis demonstrates important potential effects of GCC on the rates and biological transfer of pyrethroids by aquatic species, and the potential combined effects of these multiple stressors on two trophic levels of aquatic organisms.

Background: The relationships between both obesity and diabetes and the exposure to insecticides, specifically organophosphates and pyrethroids, in the adult Canadian population are not well-understood. Methods: Urinary concentrations of 4 organophosphate metabolites (DEP, DEPT, DMP, and DMPT) and of 4 pyrethroid metabolites (cis-DBCA, cis-DCCA, 3-PBA, and trans-DCCA) were measured for 1,147 adult Canadians aged between 18-79 years old. The geometric means and medians of both creatinine-adjusted and unadjusted urinary insecticide metabolites were estimated. Multiple linear regression and logistic regression analyses were employed to examine the associations between the insecticide metabolite concentrations and obesity and diabetes measures. Results: Both insecticides had detectable levels in over 70% of CHMS respondents. Most metabolites demonstrated a negative significant relationship between their urinary concentrations and BMI as well as waist circumference. No significant relationship was found in regard to HbA1c levels or for diabetes. Conclusion: Organophosphate and pyrethroid metabolites were detected in more than 70% of Canadian adults. Our data showed no evidence that organophosphate and pyrethroid exposures increase the risks of obesity and diabetes in adults. These results should be interpreted with caution as diet may play a large confounding role in the relationships of study.

Master of Science / Department of Entomology / Kun Yan Zhu / Cytochrome P450 monooxygenases (P450s) are important enzymes involved in the metabolism of a variety of xenobiotics, including insecticides and plant allelochemicals, and endogenous compounds, including juvenile hormones, ecdysteroids and fatty acids, in insects. Despite rapid advances in revealing various P450 genes in insects, our knowledge on the role of these genes in detoxification of insecticides is very limited. This research was to perform a genome-wide analysis of P450 genes and evaluate the role of selected P450 genes in detoxification of three commonly used pyrethroid insecticides in the yellow fever mosquito (Aedes aegypti). Our genome-wide analysis of revealed 159 P450 genes that can be classified into 18 families and 63 subfamilies. These genes are distributed in four clans, including 11 genes in the CYP2 clan, 80 in the CYP3 clan, 58 in the CYP4 clan and 10 in the mitochondrial CYP clan. The largest families are CYP6, CYP9, CYP4 and CYP325. The intron-exon organization of the genes is very diverse among the gene families, and the highest conservation of gene structures was observed in the CYP6 and CYP9 families predominantly containing single-intron genes. The phylogenetic analysis suggested that the CYP6 and CYP9 families might be derived from a common ancestor. The expression patterns of five transcripts including three individual genes (CYP6AA5, CYP6AL1 and CYP9J32) and two alternative splicing variants (CYP4J16A and CYP4J16B) of CYP4J16 were investigated in various tissues and at different developmental stages of the mosquito. Our results indicated differential expressions of these transcripts in different tissues and at different developmental stages examined. Furthermore, the exposure of the mosquitoes (larvae and adults) to each of three pyrethroid insecticides (permethrin, cypermethrin and deltamethrin) resulted in either down or up-regulation of these transcripts. Functional analyses of the selected P450 transcripts were conducted by using RNA interference (RNAi) followed by insecticide bioassay. RNAi was achieved by feeding mosquito larvae with chitosan/double stranded RNA (dsRNA) nanoparticles or injecting dsRNA to the adults. For the larvae, we obtained relatively low repressions of the P450 transcripts but the repressions were sufficient for carrying out our functional studies. Our study showed increased mortalities by 41.2% to cypermethrin when CYP6AA5 was silenced and 46.0% to permethrin when CYP9J32 was silenced. Similarly, the injection of dsRNAs in adults resulted in significant repressions of the P450 transcripts, and subsequent insecticide exposures led to a 29.3% increase in the adult mortality to cypermethrin when CYP6AA5 was silenced. Our further analysis of the nuclear receptor HR96 in the up-regulation of the P450 genes showed that when HR96 was silenced by RNAi, the up-regulation of CYP4J16B by cypermethrin was reduced by 10.1-fold but silencing HR96 did not affect the up-regulation of other P450 genes examined. These results suggest that HR96 is likely involved in regulating the expression of CYP4J16B in Ae. aegypti. However, different regulatory mechanism (s) may be involved in the up-regulation of other P450 genes examined. Model structure of CYP6AA5 was created by homology modeling and insecticides substrates were docked into the active site of this protein. Our results indicate that all three insecticides can fit into the catalytic pocket. The interaction distances between the heme iron and the putative aromatic hydroxylation site were 9.2, 9.4 and 7.2 Å for permethrin, cypermethrin and deltamethrin, respectively, whereas for aliphatic hydroxylation site these distances were 5.3, 2.8 and 2.9 Å. These results showed that CYP6AA5 may be able to metabolize cypermethrin and deltamethrin preferentially by aliphatic hydroxylation as indicated by the close interaction with the heme iron.

Male fertility is largely controlled by the hypothalamic-pituitary axis, a careful balance between stimulating and suppressing gene expression and the secretion of hormones. The critical factors for male fertility have in the past been thought to be limited to testosterone and the gonadotropins. Estrogen has only recently been demonstrated to be both a crucial requirement for fertility and a cause of infertility. Reports in the early 1990s demonstrated a decrease in mean sperm counts over the last 50 years. A hypothesis for this observation is the increase of xenoestrogens in the environment that are able to mimic and potential disrupt the natural estrogens involvement in fertility. Although the mechanisms of estrogens involvement are not yet defined, the Sertoli cells are a potential sites of action as they possess receptors for the hormone and are able to locally produce it. Sertoli cells both act to protect and provide for the male germ cells and the developing spermatozoa. Pyrethroids are common synthetic insecticides of which some have previously shown estrogenic activity. Therefore this investigation examined the effects of pyrethoids, whose estrogenicity was confirmed via the yeast assay, on the estrogen receptor expression in mouse Sertoli cells as a model for general effects of estrogenic chemicals on male fertility. The results first confirmed the estrogenicity of some pyrethroids and these pyrethroids when exposed to mouse Sertoli cells effected estrogen receptor mRNA expression however in a different way to the natural ligand 17β-estradiol.

The whitefly Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae) is a serious pest of protected vegetable and ornamental crops in most temperate regions of the world. Neonicotinoids, pymetrozine (a feeding blocker), spiromesifen (a tetronic acid derivative), bifenthrin (a pyrethroid), and pyriproxyfen (a juvenile hormone mimic) are among the most important insecticides used to control this species. Bioassays were used to quantify responses of recently-collected strains of T. vaporariorum to three neonicotinoids (imidacloprid, thiamethoxam, and acetamiprid), pymetrozine, spiromesifen, bifenthrin, and pyriproxyfen. 454 pyrosequencing was exploited to generate the first transcriptome for this species. PCR-sequencing was used to identify mutations in the target proteins of spiromesifen and bifenthrin potentially associated with resistance to these compounds. Microarray sequencing technology was employed to investigate differences in gene expression associated with pyriproxyfen resistance. Resistance to neonicotinoids was age-specific in expression and consistently associated with resistance to pymetrozine, supporting a hypothesis of metabolic resistance analogous to that in the tobacco whitefly, Bemisia tabaci. Bioassays also showed moderate to high level resistance to spiromesifen, bifenthrin and pyriproxyfen in some strains. Analysis of the transcriptome identified genes encoding enzymes involved in the detoxification of xenobiotics (cytochrome P450s, carboxyl/cholinesterases, and glutathione-s transferases) and ones encoding insecticide targets: acetyl-coA carboxylase (ACCase), the target of spiromesifen and the voltage-gated sodium channel protein targeted by pyrethroids. PCR-sequencing revealed a single nucleotide polymorphism in the ACCase gene, which was consistently associated with spiromesifen resistance. Three amino-acid substitutions in the sodium channel of pyrethroid-resistant T. vaporariorum were found in positions previously implicated in pyrethroid resistance in B. tabaci. Microarray sequencing disclosed that a cytochrome P450 gene (CYP4G61) was overexpressed in a strain selected for increased pyriproxyfen resistance. The implications of these results and opportunities for further work are discussed.

The synthesis and insecticidal activity of a series of 2,2-dicyano cyclopropane carboxylic acids, (3-phenoxyphenyl)- methyl esters were investigated. Synthesis of the compounds was accomplished by reaction of a dimethyl sulfonium carbethoxy ylide with propanedinitrile alkylidene compounds. Final products were formed in one step by use of the (3-phenoxyphenyl)-methyl ester of the ylide. Insecticidal activity was determined at 500 ppm application with Permethrin as the standard against houseflies, mexican bean beetles, and southern army worms.

Le principal objectif des travaux présentés dans ce manuscrit était d’étudier certains paramètres régissant l’efficacité et la durabilité de moustiquaires avec des molécules insecticides incorporées dans les fils de polyéthylène. Pour cela deux axes de travail ont été identifiés : l’étude des phénomènes de migration des molécules insecticide dans les fils de polyéthylène et l’étude des mécanismes de photo-dégradation de l’insecticide étudié : la deltaméthrine.L’étude de l’influence du procédé de fabrication des moustiquaires sur la morphologie du polyéthylène a permis de montrer que l’étape d’étirage à froid était critique dans la définition des propriétés morphologiques (cristallinité et orientation de la structure cristalline) et mécaniques des fils. L’effet du recuit observé est plus modéré (légère augmentation de l’épaisseur des lamelles cristallines). Néanmoins, il a été montré que les modifications induites par le recuit sur la morphologie du polyéthylène ont une influence sur les phénomènes de migration des molécules insecticides dans les fils. En effet, alors qu’un retard est observé dans les courbes de désorption des fils non recuits, ce retard disparaît pour les fils recuits. Il a été également montré que la faible vitesse d’évaporation de la deltaméthrine permet de limiter la migration de la deltaméthrine hors des fils.L’étude de la photo-dégradation de la deltaméthrine a permis de mettre en évidence les principaux mécanismes de dégradation (isomérisation, scission de la fonction ester et de la fonction cyclopropane). L’ajout d’additifs de type antioxydants ou filtres UV permet de limiter la vitesse de dégradation de la deltaméthrine / The main objective of the works presented in this manuscript was to study some of the parameters ruling the efficacy and the durability of the mosquito nets with incorporated insecticide in the polyethylene yarns. To achieve this goal, two lines of research were identified: the study of the insecticide migration phenomena in the yarns and the study of the photodegradation mechanisms of the molecule of interest: the deltamethrin.The study of the influence of the nets fabrication process on the polyethylene morphology showed that the cold-drawing step was critical to define the morphological (crystallinity and orientation of the crystalline structure) and mechanical properties. The observed influence of the heat-setting appeared less important (slight increase of the crystalline lamellae thickness). However, the heat-setting induced modifications which affected the migration of the insecticide molecules in the yarns. Indeed, while a delay is observed in the desorption curves of the non-heat-set yarns, this time-lag disappeared in the heat-set yarns. It was also shown that the low evaporation rate of deltamethrin permits to impede the migration of deltamethrin out of the yarns.The study of the photodegradation of deltamethrin permitted to highlight the main degradation mechanisms (isomerization, ester cleavage and cyclopropane cleavage). Antioxidant and UV absorber additives can be used to reduce the deltamethrin degradation rate

<p>Soil from local beech-forest, spruce-forest and an industrial area was taken. Control- and test-microcosms containing 150 ml soil were spiked with cypermethrin 0,4 mg/ml soil. Cypermethrin residues were extracted on day seven and 14.</p><p>Cyclohexane and deionized water was utilized in multiple step extraction processes. Samples were analyzed in a Gas Chromatograph (GC) with electron capture detector (ECD). </p><p>Concentration values for the samples were highest for beech-forest soil and lower for the other two soil-types. Statistical differences in concentrations between control- and test-microcosms for each soil-type on day seven and day 14 were evaluated with Mann Whitney U tests. Significant result was only found in the industrial 14-day group. The small amounts of cypermethrin in the extracts could not only be ascribed to a bacterial degradation process. Used insecticide has a high bonding affinity for particles and is sequestered in soil.</p>