<p>The primary goal of this research study was to provide updated pest management recommendations to growers, including the reduction of insecticide applications on a calendar basis by the use of pest economic thresholds, with the purpose of maximizing insecticide efficacy while minimizing the associated negative impacts on natural enemies and their ecosystem services. </p> <p>Commercial watermelon (<i>Citrullus lanatus</i>) production in the Midwest typically relies on neonicotinoid and pyrethroid insecticides to manage insect pests, particularly striped and spotted cucumber beetles (<i>Acalymma vittatum </i>Fabricius and <i>Diabrotica undecimpunctata</i> <i>howardi</i> Barber, respectively). The role of arthropod predators in managing cucumber beetles is not well documented, and data on the effects of insecticides on predators in watermelon production are deficient. Common cucumber beetle predators include coccinellid beetles found on plants, ground-dwelling carabid beetles (Coleoptera: Carabidae) and spiders in several families that inhabit the soil surface in watermelon fields. I hypothesize that these generalist predators and the ecosystem services (e.g., pest predation) they provide are at risk from insecticides used for pest management without regard to economic thresholds. My study compared the effect of insecticide use on cucumber beetle pests, spider predators, collembola populations and field pest predation under two treatments: 1) watermelons treated with neonicotinoid soil drench and subsequent pyrethroid sprays, surrounded by corn with neonicotinoid-treated seeds (Conventional), and 2) watermelons treated only with pyrethroid spray when economic thresholds were reached, surrounded by corn with untreated seeds (IPM).</p> <p>The frequent application of insecticides decreased cucumber beetles in the watermelon plots managed with Conventional pest management; however, they also reduced spider predators, collembola densities, and field pests predation measurements, possibly due to the subsequent pyrethroids applications during the growing season. In addition, our study showed that neonicotinoid seed treatment in corn had no negative impact on any of the above-mentioned response variables measured. </p> <p>Ultimately, following an IPM strategy and the use of pest monitoring helped to reduce unnecessary insecticides applications, conservation of pest regulatory services provided by natural enemies, and possibly less ecological impact to manage significant insect pests in watermelon plots. <b><br> </b></p>

A field experiment tested the effectiveness of carbaryl and two pyrethroid insecticides, cyfluthrin and esfenvalerate, in protecting high-value Engelmann spruce trees from attack by Dendroctonus rufipennis Kirby. Carbaryl suspension at the 2% registered rate and a reduced rate of 1 % were both effective in protecting Engelmann spruce from attack by D. rufipennis through two pheromone baiting periods and 24 months following insecticide application . Cyfluthrin at 0.025% rate and esfenvalerate at 0.025 and 0.05% rates provided effective protection through one pheromone baiting and 12 months following insecticide application. Only cyfluthrin at 0.008% rate was judged ineffective protection 12 months following insecticide application. A laboratory evaluation utilizing a 32-h bioassay on D. rufipennis adults determined all three insecticides were toxic by contact. Carbaryl and piperonyl butoxide bioassays testing synergism were inconclusive. The methodology presented provides a means for forest land managers to quantify insecticide toxicity and monitor for resistance development.

Annual bluegrass weevil (Listronotus maculicollis Kirby) (Coleoptera: Curculionidae) (ABW) is a major pest of annual bluegrass (Poa annua L.) and creeping bentgrass (Agrostis stolonifera L.) on golf courses in the northeastern United States. The asynchronous life cycle makes managing ABW difficult, putting emphasis on scouting to achieve accurate insecticide timing and acceptable control. Little is known about the biology and management of ABW in Virginia's more temperate climate. Reported cases of ABW resistance to pyrethroids (IRAC Group 3) continues to grow in the northeast, yet no pyrethroid-resistance cases have been reported in Virginia outside of the metropolitan Washington, D.C. For this thesis, I confirmed the widespread distribution of ABW across Virginia with a survey of golf course superintendents. Two golf courses in southwestern Virginia were monitored weekly during the 2019 and 2020 growing seasons to determine the seasonal biology of ABW within this region. These data suggest that overwintering ABW emerge much earlier than described in the northeast, with adult weevil activity beginning in late February or early March. I observed three complete ABW generations, with a potential fourth generation. Soil plugs from the same two golf courses were used to compare the salt floatation and Berlese-Tullgren funnel methods of larval extraction. The methods were highly correlated (R2 = 0.7856), suggesting either method is appropriate for ABW larval extraction. Bioassays conducted on adult ABW from the same two golf courses showed that field rate concentrations of the pyrethroid bifenthrin showed variable mortality ranging from 20% to 80% suggesting the presence of resistance genes in the population. A 100-fold rate of bifenthrin resulted in 100% mortality of ABW, however. Because cross-resistance has been reported among northeastern ABW populations, the common insecticide active ingredients chlorpyrifos (IRAC Group 1B: Organophosphate), trichlorfon (IRAC Group 1B: Organophosphate), λ-cyhalothrin (IRAC Group 3: Pyrethroid), α-cypermethrin (IRAC Group 3: Pyrethroid), imidacloprid (IRAC Group 4A: Neonicotinoid), and spinosad (IRAC Group 5: Spinosyn), were tested on ABW adults. In another bioassay, two organophosphates, trichlorfon and chlorpyrifos, resulted in significantly higher ABW mortality rates than all other labeled insecticides (P < 0.0001). Two other larvicides, spinosad and α-cypermethrin, also exhibited adult control, an important factor to consider for ABW management and preventing pyrethroid-resistance. These results provide valuable insight into the seasonal biology and management of ABW in Virginia and direction for further investigation into these populations. / Master of Science in Life Sciences / Annual bluegrass weevil (Listronotus maculicollis Kirby) (ABW) is a tiny, but damaging insect pest of cool-season golf course turfgrasses in the northeastern United States. As pest populations have spread southward, ABW has become an emerging pest in Virginia. The objectives of this thesis were to 1) determine the geographic distribution and seasonal biology of ABW in Virginia, 2) compare two methods for extracting ABW larvae from turf cores in order to estimate larval densities, and 3) to assess the susceptibility of ABW to various insecticides commonly used by golf course superintendents. A survey of golf course superintendents in 2019 revealed widespread prevalence of ABW across Virginia, particularly in areas growing predominantly cool-season turfgrasses. Two golf courses in southwestern Virginia were monitored weekly during the growing seasons of 2019 and 2020 to determine the seasonal biology of ABW. Data suggest that overwintering ABW emerge much earlier than reported in the northeast, with adult weevil activity beginning in late February or early March compared to April in the northeast. In addition, I detected three complete ABW generations, with a possible fourth generation occurring. Soil plugs from two golf courses were used to compare a heat extraction method using a Berlese-Tullgren funnel with the traditional salt float method for extraction of ABW larvae. The two methods extracted similar numbers of ABW larvae suggesting that either method is appropriate for ABW larval extraction. Adult ABW from the same two golf courses were collected and subjected to the pyrethroid insecticide bifenthrin at 0.128 kg ai ha-1 (field application rate), 1.28 kg ai ha-1 (10-fold rate), 12.8 kg ai ha-1 (100-fold rate), along with a water control. Results indicated that the field application rate of bifenthrin killed > 50% but <90% of ABW adults, suggesting that some resistance may be present in the population. A concentration of 100-fold bifenthrin field rate killed 100% of tested individuals, suggesting that widescale field resistance to pyrethroids is likely not present. Because cross-resistance has been reported among northeastern ABW populations, the common insecticide active ingredients chlorpyrifos (IRAC Group 1B: Organophosphate), trichlorfon (IRAC Group 1B: Organophosphate), λ-cyhalothrin (IRAC Group 3: Pyrethroid), α-cypermethrin (IRAC Group 3: Pyrethroid), imidacloprid (IRAC Group 4A: Neonicotinoid), and spinosad (IRAC Group 5: Spinosyn), were tested on ABW adults from the same two golf courses. Two organophosphates, trichlorfon, a larvicide, and chlorpyrifos resulted in significantly higher ABW mortality rates than all other active ingredients (P < 0.0001). Two other larvicides, spinosad and α-cypermethrin, also exhibited adult control, an important factor to consider when attempting to manage ABW and preventing resistance to pyrethroids. Our results provide valuable insight into the seasonal biology and management of ABW in Virginia and direction for further investigation into these populations.

During recent years most of the successful developments in pyrethroids have been primarily concerned with structural or compositional variations. As a part of our continuing interest in pyrethroid insecticides, nitrogen-containing compounds having pyrethroid-like structures were synthesized. Seven prolinate compounds, N-(substituted)-phenyl-prolinates and N-carbobenzoxy-prolinates were coupled with known pyrethroid alcohols. These structural variations which "locked in" a specific conformation between the nitrogen and chiral a-carbon in the acid moiety of fluvalinate were studied to determine the influence of certain conformations on insecticidal toxicity. The toxicity data for the prolinate compounds showed intermediate mortality against nonresistant cockroaches. It was concluded that the conformation imposed by the proline ring portion of the esters was probably close to the favored conformation for interaction of fluvalinate-like pyrethroids with the insect receptor site. A second series of nitrogen-containing compounds, twenty-five carbamate esters resulting from the condensation of N-isopropyl-(substituted)-anilines and N-alkyl-(substituted)-benzylamines with appropriate pyrethroid alcohols were studied for insecticidal activity. These studies were conducted on pyrethroid-susceptible houseflies. Some of the carbamate esters exhibited high toxicity when synergized by piperonyl butoxide. For example, the toxicity ( LD 50 ) of O-a-cyano-3-phenoxyfaenzyl-N-a,a-dimethyl-4-bromo-benzyl carbamate was 0.012 ug/g, which is significantly greater than that reported for the potent pyrethroid, fenvalerate. Correlations of insecticidal activity with respect to structure and conformational factors of the carbamate esters have been made. The N-isopropyl substituent decreases insecticidal activity in the N-benzyl-derived compounds, while the N-isopropyl substituent enhances activity in the N-phenyl-derived compounds. Certain substituents on the phenyl ring of both analogs greatly affect insecticidal potency of the carbamate esters. Also, some alkyl substituents (especially, a,cx-dimethyl and a-cyclopropyl groups) on the benzylic carbon of the benzylamine series enhance toxicity. The a,a-dimethyl branching of the N-benzyl carbamate approximates the steric shape given by the gemdimethyl group for conventional cyclopropane ring-containing pyrethroids. The N-benzyl compounds are significantly synergized by piperonyl butoxide, particularly those in which the carbamate nitrogen atom is mono-substituted.

O mosquito Aedes (Stegomyia) aegypti Linnaeus, 1762 é o principal vetor do vírus do dengue sorotipo 1-4 (DEN 1-4) e da febre amarela. Por não haver vacina disponível, a redução da transmissão da dengue só pode ser alcançada mediante o controle do vetor. Entre as medidas de controle, os órgãos responsáveis utilizam-se de compostos químicos, principalmente organofosforados. Além disso, devido ao grande incomodo causado pelo Aedes, a população faz uso de inseticidas domésticos, a base de piretróides, na tentativa de eliminar e ou repelir o mosquito. As repetidas aplicações destes inseticidas e seu uso contínuo possibilitam o desenvolvimento de resistência em populações de mosquitos, processo resultante do efeito seletivo de exposição a dosagens que matam os indivíduos suscetíveis, sobrevivendo os resistentes, que transferem essa capacidade a seus descendentes. Dentre os mecanismos de resistência, a redução da sensibilidade do sítio alvo é dada por mutações pontuais no sitio de ação dos inseticidas. Tais mutações podem levar a uma substituição de aminoácidos na molécula alvo e a uma diminuição da afinidade do inseticida com essa molécula. No caso dos piretróides a mudança estrutural na molécula formadora do canal de sódio (Nav), sítio alvo deste inseticida, é a causa da resistência tipo knockdown resistence (kdr), um mecanismo de resistência bastante conhecido. Em Aedes aegypti, a associação entre a presença da mutação V1016I e o fenótipo de resistência a piretróide já foi verificada em algumas regiões Brasileiras, utilizando primers alelo-específicos. A mutação I1011M também está associada à resistência a piretróides e já foi descrita no Brasil. O objetivo deste estudo foi determinar a frequência destas mutações que levam às substituições V1016I e I1011M no AaNav de populações de Aedes aegypti no estado de São Paulo e avaliar a evolução desta frequência no período de dez anos. Para isso, indivíduos coletados em 2001 e 2011 tiveram o DNA extraído e primers alelo específicos foram utilizados para a realização de PCR a fim de verificar a presença da mutação. Houve um aumento significativo do alelo 1016 Ile nas populações estudadas, comparando-se os anos 2001 e 2011. Entretanto para o alelo 1011 Met, somente a população de Santos apresentou essa diferença significativa. Este aumento na frequência destas mutações pode ter sido ocasionado pela utilização de inseticidas domésticos à base de piretróides, uma vez que os órgãos de controle interromperam a utilização desses compostos / The mosquito Aedes (Stegomyia) aegypti Linnaeus, 1762 is the main vector of the virus dengue serotypes 1-4 (DEN 1-4) and the yellow fever virus. As there is not vaccine available, the reduction of the transmission of dengue can only be achieved by controlling the vector. Among the control measures, the responsible agencies use chemical compounds, organophosphate mainly. Furthermore, due to the big nuisance caused by Aedes, the population makes use of domestic insecticide, pyrethroids based, trying to eliminate or repel the mosquito. The repeated applications of these insecticides and the continuous use of them enable the resistance development in the mosquitoes population. This process is the result of selective effect of exposure to dosages that can kill the susceptible individuals, and then the surviving individuals transfer these characteristics to their descendents. Among the mechanism of resistance, the reduction of sensibility of the target site is given by punctual mutation (SNIP) in the action site of the insecticides. This mutation can lead to a substitution of amino acids in the target molecule and a reduction of affinity of the insecticide with this molecule. In the case of pyrethroids, the structural change in the forming molecule of the sodium channel (Nav), target site of this insecticide, is the cause of knockdown resistence (kdr) type. In Aedes aegypti, the association between the presence of the mutation V1016I and the pyrethroid resistance phenotype has been previously verified in many Brazilian regions, using Allele Specific primers The mutation I1011M is also associated with the pyrethroids resistance and it has been described in Brazil. The objective of the this study was to determine the frequency of the mutations that leads to the substitutions V1016I e I1011M in AaNav of the Aedes aegypti population in the state of Sao Paulo and to evaluate the evolution of this frequency in the period of ten years. Therefore, collected individuals in 2001 and 2011 had their DNA extracted and specific primers were used for PCR, in order to verify the presence of the mutation. There was a significant raise of allele 1016 Ile in the studied population, comparing the years 2001 and 2011. Nevertheless for allele 1011 Met, only the population of Santos showed this significant difference. This raise in the frequency of these mutations may have been caused by the utilization of domestic insecticides pyrethroid based, whereas the control agencies interrupted the utilization of this compost

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-03-27T19:09:45Z No. of bitstreams: 1 2013 - Lilian Cristina de Sousa Oliveira Batista.pdf: 1288520 bytes, checksum: 258e3cf77d272f259a164d0a1e9ca8fa (MD5) / Made available in DSpace on 2018-03-27T19:09:46Z (GMT). No. of bitstreams: 1 2013 - Lilian Cristina de Sousa Oliveira Batista.pdf: 1288520 bytes, checksum: 258e3cf77d272f259a164d0a1e9ca8fa (MD5) Previous issue date: 2013-02-27 / CNPq / FAPERJ / FAPUR / The objective of the present study was to evaluate through in vitro test, the efficacy and residual period of protection in an aerosol formulation of pyriproxyfen and cyfluthrin in the Ctenocephalides felis felis control. A white felt of one millimeter of thickness and two square meters was impregnated with a formulation at a concentration of 0.04% of cyfluthrin and 0.05% of pyriproxyfen (Fleegard ? Bayer), and after dried, retained at a natural conditions environment until the challenge?s day. For each day of weekly challenge, six strips of impregnated carpet and six control strips, without treatment were used. For the test with immature forms, each strip was placed in a test tube with 10 eggs or 10 larvae and a half gram of a required diet for the larval development. The tubes were inside an incubator at a temperature of 28 ? 1 ?C and relative humidity of 75 ? 10%. At the 25th day after the incubation, the material of each challenge was fixed with alcohol 70 ?GL and the quantification of adults emerged from puparium was performed with the aid of a stereoscopic microscope. The average efficacy of egg-adult interruption of development was 98.78%, with minimum variation 89.47% and maximum 100%, and the larvae-adult was 96.16%, with minimum variation 82.14% and maximum 100%, over 182 days of challenge. For the test with adults were placed ten fleas not fed C. felis felis in each tube, being five male and five females. It was recorded the number of live and dead in times of 10 minutes, 30 minutes, one hour, two hours, three hours, four hours and 24 hours with the aid of a stereoscopic microscope on days 0 (30 min after impregnation of the felt), +1, +2, +5, +10, +15, +20 and +30 and was found to effectively, respectively of 35.7; 88.5; 75.9; 66.7; 67.6; 40.7; 22.2 and 12.3. It can be concluded that in aerosol formulation of cyfluthrin and pyriproxyfen was effective on the control of immature stages of C. felis felis for up to 26 weeks and adults after 24 h exposure to the product with residual action period extending substantially up to two days after the impregnation of felt. / O objetivo do presente trabalho foi avaliar atrav?s de teste in vitro, a efic?cia e o per?odo residual de prote??o de uma formula??o aerossol de piriproxifen e ciflutrina no controle de Ctenocephalides felis felis. Um feltro branco com um mil?metro de espessura e dois metros quadrados foi impregnado com a formula??o na apresenta??o de aerossol, em uma concentra??o de 0,04% de ciflutrina e de 0,05% de piriproxifen (Fleegard? BAYER) e ap?s a secagem, mantido no ambiente em condi??es naturais at? o dia de desafio. Foram utilizadas seis tiras de feltro impregnadas com o produto e seis tiras controle, sem tratamento, para cada dia de desafio semanal. Para o teste com formas imaturas, cada tira foi colocada em tubo de ensaio contendo 10 ovos ou 10 larvas e meio grama de uma dieta necess?ria para o desenvolvimento larval. Os tubos foram mantidos em c?mara climatizada com temperatura de 28?1?C e umidade relativa de 75?10%. No 25? dia ap?s a incuba??o, o material de cada desafio foi fixado com ?lcool 70?GL e realizada a quantifica??o de adultos emergidos do pup?rio com aux?lio de microsc?pio estereosc?pico. A efic?cia m?dia da interrup??o do desenvolvimento ovo-adulto foi de 98,78%, com varia??es m?nima de 89,47% e m?xima de 100%, e para a larva-adulto foi de 96,16%, com varia??es m?nima de 82,14% e m?xima de 100%, ao longo de 182 dias de desafio. Para o teste com adultos foram colocadas dez pulgas adultas n?o alimentadas de C. felis felis em cada tubo, sendo cinco machos e cinco f?meas. Foi registrado o n?mero de insetos vivos e mortos nos tempos de 10 minutos, 30 minutos, uma hora, duas horas, tr?s horas, quatro horas e 24 horas com aux?lio de um microsc?pio estereosc?pico, nos dias 0 (30 minutos ap?s a impregna??o do feltro), +1; +2; +5; +10; +15; +20 e +30 e constatou-se a efic?cia, respectivamente de 35,7; 88,5; 75,9; 66,7; 67,6; 40,7; 22,2 e 12;3. P?de-se concluir que a formula??o aerossol de ciflutrina e piriproxifen foi eficaz no controle ambiental de formas imaturas de C. felis felis por um per?odo de 26 semanas e para adultos 24 h ap?s a exposi??o ao produto com per?odo residual de a??o estendendo-se de forma significativa por at? dois dias ap?s a impregna??o do feltro.

Pesticide use in the United States continues to attract negative public attention. In recent years, this attention has focused on the effects that chronic, low-level pesticides may have, especially on children and various sub-populations. Over the past decade, studies have attempted to correlate negative health effects with detections of pesticide biomarkers in biological media. The current research investigates biomarker of exposure levels in a sample of the United States population. Data from the 2001-2002 NHANES dataset (n=11,039) was evaluated. The detection frequency of urinary biomarkers of exposure and the geometric mean from the NHANES pesticide dataset (n=3,152) were determined. Of the 18 specific pesticide biomarkers, three were detected in more than 50% of the sample: 79% had a detectable level of 3,5,6-trichloropyridinol, a biomarker of chlorpyrifos, with a geometric mean of 2.07 µg/L (C.I: 1.98-2.17); 53% had a detectable level of paranitrophenol, a biomarker of methyl parathion, with a geometric mean of 0.367 µg/L (C.I.: 0.346-0.389); and 77% had a detectable level of 3-phenoxybenzoic acid, a biomarker of permethrin, with a geometric mean of 0.336 µg/L (C.I.: 0.320-0.352). These levels fall within the range of other epidemiological and biomonitoring studies investigating background levels of biomarkers in the general population. The association between the detection of a biomarker and variations in mean height and weight of children aged 6-11 was evaluated. No significant results were found when evaluating these differences for 3,5,6-trichloropyridinol exposure. Paranitrophenol associated with shorter children at age 8 [Non-Detect=134.3 cm and Detect: 130.9 cm (p=0.046)] and taller children at age 11 [Detect=153.7 cm and Non-Detect=149.9 cm (p=0.022)]. Heavier children associated with 3-Phenoxybenzoic Acid at age 7: [Detect=28.61 kg and Non-Detect=25.26 kg (p=0.009)]. Clinical chemistry biochemical concentration comparisons were made between individuals that had a detectable level of the biomarker in urine and those that did not. Two biochemicals had a significant difference across all three biomarkers: cholesterol and sodium. The biochemical levels with significant difference between detects and non-detects for the biomarkers were not elevated above clinical reference values. Overall, there is insufficient evidence to suggest a relationship between background pesticide exposures in this sample and negative health effects.

Made available in DSpace on 2014-06-11T19:29:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-28Bitstream added on 2014-06-13T19:59:38Z : No. of bitstreams: 1 rotundo_m_me_ilha.pdf: 850611 bytes, checksum: 1909101afb4dae7d59c34fa46384f158 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A exposição dérmica de amostradores foi avaliada na reentrada em lavoura de algodão após pulverização com o inseticida deltametrina. Aos 3 minutos após a aplicação quatro pessoas vestiram um conjunto de roupas (calça, camisa e luvas), entrando e permanecendo na área tratada por 30 minutos, simulando uma amostragem de pragas. O procedimento foi repetido aos 60 e 300 minutos e aos 1, 3, e 7 dias após a aplicação. Partes do tecido, correspondentes ao local de contato com várias partes do corpo, foram recortadas e analisadas quanto à quantidade de resíduos presentes. O inseticida foi extraído das roupas com acetato de etila e a determinação quantitativa foi feita por cromatografia gasosa. As exposições foram extrapoladas para uma jornada de trabalho de oito horas. Para classificar a segurança das condições de trabalho foram estimadas a margem de segurança (MS), dose tóxica (%DT/dia), dose tolerável dérmica e o tempo de trabalho seguro. O conjunto correspondente aos antebraços/braços/mãos concentrou 61,27% dos resíduos presentes na roupa. Partes correspondentes ao peitoral, pernas, coxas e costas alcançaram 13,40; 9,33; 9,32; e 6,65% dos resíduos totais encontrados nas roupas, respectivamente. Pela análise dos dados constatou-se que o intervalo de reentrada estabelecido para o produto comercial Decis 25 CE (deltametrina) que é de 24 h está superestimado. / The objective of this work was to study the dermal exposure of workers to residues of the deltamethrin, applied in cotton. After 3 minutes of application four people dressed a group with cotton clothes (pant, shirt and gloves), entered and stayed in the treated area by 30 minutes, simulating a sampling. The procedure was repeated after 60 and 300 minutes and 1, 3, and 7 days of the application. The clothes were cut and put in plastic bags, and stored cold at -18º until analyses was performed. The analytical method consisted on the extraction of deltamethrin residues with a ethyl acetate and the quantitative determination was done by gas chromatograph. Exposure was extrapolated to a work day of 8 hours. To evaluate safety's conditions at work was estimated the Working Condition Unsafe (margin of safety - MOS <1), Poisonous Dose (%PD/day), Dermal Dose Tolerable and the estimate of Safe Work Duration (SWD). The corresponding group for the forearms/arms/hands concentrated 61.27% of present residues in the clothes. The residues found on the clothes, chest, legs, lame and back, were 13.40, 9.33, 9.32, and 6.65%, respectively. Results of deltamethrins amounts trapped on cotton clothes showed that 24h as a reentry interval for Decis 25 EC is overestimated.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Studies have shown that pesticide exposure is a risk factor to Parkinson Disease (PD) development in urban areas and mainly in rural areas. One of these pesticides, Deltamethrin (DM), is used indiscriminately for vector control in crops, veterinary medicine and control of domestic pests. The aim of the study is investigate the motor, cognitive and neurochemical changes caused by repeated administration of DM in rats. 38 Male Wistar rats were used, 9-10 months-old, from the Neurophysiology Laboratory animal house of UFS. The study was divided into two experiments: (1) intranasal (i.n.) and (2) intracerebroventricular (i.c.v.). In the (1), the animals were divided into 2 groups (CTR, 0.9% saline solution, n=9) and DM 0.5 (treated with DM 0.5 mg, n=10), that received 3 infusions administrated one every 7 days. During the treatment, the animal were subjected to behavior test: catalepsy, novel object recognition task, spontaneous alternation and contextual conditioned fear. In i.c.v. experiment, the animals were divided into 3 groups: control (CTR, n=7); DM 0.5 (treated with DM 0.5 μg diluted in 2 μL, n=7) and DM 5 (treated with DM 5 μg diluted in 2 μL, n=5). In the experiment (2), the animals received 3 i.c.v. injections (2 μL/injection), one each 48 hours. During the treatment, the rats were submitted to behavior test: catalepsy, open field test and spontaneous alternation. After the behavior tests of both experiments, the rats were anesthized, perfused transcardially, their brains removed and submitted to Tyrosine Hydroxylase (TH) immunochemistry in Substancia Nigra pars compacta (SNpc), Ventral Tegmental Area (VTA) and dorsal striatum areas. In i.n. experiment, there were motor changes in open field and cognitive changes in novel object recognition task and contextual conditioned fear. The immunohistochemistry shows a reduction of TH+ cells in SNpc and VTA and an increase of Optical Density in dorsal striatum. In i.c.v. experiment, it was observed motor changes in open field and cognitive changes in spontaneous alternation. In immunohistochemical there was a decrease of TH + cells in DM 5ug animals in SNpc and VTA and decreased their levels in DM 0.5 g and DM 5 ug groups in the dorsal striatum. In both experiments, cognitive changes preceded the motor changes. The data presented contribute to understanding of physiological and behavioral changes after exposure to DM and more studies are needed to elucidate the DM as a possible cause of parkinsonism symptoms. / Estudos tem demonstrado que a exposição a pesticidas é um fator de risco para o desenvolvimento da doença de Parkinson (DP) em áreas urbanas e principalmente em áreas rurais. Um desses pesticidas, a deltametrina (DM), é utilizada indiscriminadamente no controle de vetores na lavoura, na medicina veterinária e no controle de pestes domésticas. Diante disso, o objetivo da pesquisa é avaliar as alterações motoras, cognitivas e neuroquímicas causadas pela administração repetida da DM em ratos. Foram utilizados 38 ratos Wistar machos, com idade entre 9-10 meses, provenientes do Biotério do Laboratório de Neurofisiologia da UFS. O trabalho foi dividido em dois experimentos: (1) administração intranasal (i.n.) e (2) intracerebroventricular (i.c.v.) de DM. No experimento 1 (intranasal), os animais foram divididos em 2 grupos: controle (CTR, solução salina 0,9%, n=9) e DM 0,5 (tratados com DM 0,5 mg, n=10), que receberam 3 infusões intranasais administradas 1 a cada 7 dias. Durante o tratamento, os animais foram submetidos a testes comportamentais: catalepsia, reconhecimento de objeto novo, alternação espontânea e medo condicionado ao contexto. No experimento 2 (i.c.v.), os animais foram divididos em 3 grupos: controle (CTR, n=7), DM 0,5 (tratados com DM 0,5 μg em 2 μL, n=7) e DM 5 (tratados com DM 5 μg em 2 μL, n=5). Nessa etapa, os animais receberam 3 injeções i.c.v. (2 μL por injeção), uma a cada 48h. Ao longo do tratamento, os ratos foram avaliados nos testes da catalepsia, campo aberto e alternação espontânea. Após os testes de comportamento em ambos experimentos, os ratos foram anestesiados, perfundidos, seus cérebros removidos e submetidos a imunohistoquímica para Tirosina Hidroxilase (TH) na substância negra parte compacta, área tegmental ventral e estriado dorsal. Foi observado no experimento i.n. que houve alterações motoras no campo aberto e cognitivas no reconhecimento de objeto novo e no medo condicionado ao contexto. A imunohistoquímica mostrou redução de células TH+ na SNpc e VTA e aumento de TH+ no estriado dorsal. No experimento i.c.v., foram observadas alterações motoras no campo aberto e cognitivas na alternação espontânea. Na imunohistoquímica houve diminuição de células TH+ nos animais DM 5 μg na SNpc e em VTA e redução de seus níveis nos grupos DM 0,5 μg e DM 5 μg no estriado dorsal. Em ambos os experimentos, alterações cognitivas precederam as alterações motoras. Os dados apresentados contribuem no entendimento sobre alterações fisiológicas e comportamentais após exposição a DM e mais estudos deverão ser realizados para elucidar a DM como um possível causador de sintomas de parkinsonismo.

O mosquito Aedes (Stegomyia) aegypti Linnaeus, 1762 é o principal vetor do vírus do dengue sorotipo 1-4 (DEN 1-4) e da febre amarela. Por não haver vacina disponível, a redução da transmissão da dengue só pode ser alcançada mediante o controle do vetor. Entre as medidas de controle, os órgãos responsáveis utilizam-se de compostos químicos, principalmente organofosforados. Além disso, devido ao grande incomodo causado pelo Aedes, a população faz uso de inseticidas domésticos, a base de piretróides, na tentativa de eliminar e ou repelir o mosquito. As repetidas aplicações destes inseticidas e seu uso contínuo possibilitam o desenvolvimento de resistência em populações de mosquitos, processo resultante do efeito seletivo de exposição a dosagens que matam os indivíduos suscetíveis, sobrevivendo os resistentes, que transferem essa capacidade a seus descendentes. Dentre os mecanismos de resistência, a redução da sensibilidade do sítio alvo é dada por mutações pontuais no sitio de ação dos inseticidas. Tais mutações podem levar a uma substituição de aminoácidos na molécula alvo e a uma diminuição da afinidade do inseticida com essa molécula. No caso dos piretróides a mudança estrutural na molécula formadora do canal de sódio (Nav), sítio alvo deste inseticida, é a causa da resistência tipo knockdown resistence (kdr), um mecanismo de resistência bastante conhecido. Em Aedes aegypti, a associação entre a presença da mutação V1016I e o fenótipo de resistência a piretróide já foi verificada em algumas regiões Brasileiras, utilizando primers alelo-específicos. A mutação I1011M também está associada à resistência a piretróides e já foi descrita no Brasil. O objetivo deste estudo foi determinar a frequência destas mutações que levam às substituições V1016I e I1011M no AaNav de populações de Aedes aegypti no estado de São Paulo e avaliar a evolução desta frequência no período de dez anos. Para isso, indivíduos coletados em 2001 e 2011 tiveram o DNA extraído e primers alelo específicos foram utilizados para a realização de PCR a fim de verificar a presença da mutação. Houve um aumento significativo do alelo 1016 Ile nas populações estudadas, comparando-se os anos 2001 e 2011. Entretanto para o alelo 1011 Met, somente a população de Santos apresentou essa diferença significativa. Este aumento na frequência destas mutações pode ter sido ocasionado pela utilização de inseticidas domésticos à base de piretróides, uma vez que os órgãos de controle interromperam a utilização desses compostos / The mosquito Aedes (Stegomyia) aegypti Linnaeus, 1762 is the main vector of the virus dengue serotypes 1-4 (DEN 1-4) and the yellow fever virus. As there is not vaccine available, the reduction of the transmission of dengue can only be achieved by controlling the vector. Among the control measures, the responsible agencies use chemical compounds, organophosphate mainly. Furthermore, due to the big nuisance caused by Aedes, the population makes use of domestic insecticide, pyrethroids based, trying to eliminate or repel the mosquito. The repeated applications of these insecticides and the continuous use of them enable the resistance development in the mosquitoes population. This process is the result of selective effect of exposure to dosages that can kill the susceptible individuals, and then the surviving individuals transfer these characteristics to their descendents. Among the mechanism of resistance, the reduction of sensibility of the target site is given by punctual mutation (SNIP) in the action site of the insecticides. This mutation can lead to a substitution of amino acids in the target molecule and a reduction of affinity of the insecticide with this molecule. In the case of pyrethroids, the structural change in the forming molecule of the sodium channel (Nav), target site of this insecticide, is the cause of knockdown resistence (kdr) type. In Aedes aegypti, the association between the presence of the mutation V1016I and the pyrethroid resistance phenotype has been previously verified in many Brazilian regions, using Allele Specific primers The mutation I1011M is also associated with the pyrethroids resistance and it has been described in Brazil. The objective of the this study was to determine the frequency of the mutations that leads to the substitutions V1016I e I1011M in AaNav of the Aedes aegypti population in the state of Sao Paulo and to evaluate the evolution of this frequency in the period of ten years. Therefore, collected individuals in 2001 and 2011 had their DNA extracted and specific primers were used for PCR, in order to verify the presence of the mutation. There was a significant raise of allele 1016 Ile in the studied population, comparing the years 2001 and 2011. Nevertheless for allele 1011 Met, only the population of Santos showed this significant difference. This raise in the frequency of these mutations may have been caused by the utilization of domestic insecticides pyrethroid based, whereas the control agencies interrupted the utilization of this compost