The research presented herein provides information on coelomocyte (leukocyte) collection, function and immunotoxicity from polychlorinated biphenyls (PCB) in the earthworm Lumbricus terrestris. Research was undertaken as part of an overall goal to develop a well-documented and scientifically valid non-mammalian surrogate immunoassay with the earthworm Lumbricus terrestris to assess immunotoxic potential of xenobiotics. The principal objectives were to: (1) Develop an extrusion model for analyzing immunotoxicity of xenobiotics; (2) determine if coelomocytes can be collected repeatedly without obvious harm to the earthworm or change in immune response of the coelomocytes harvested and (3) validate the response sensitivity profiles of a panel of biomarkers {differential and total cell counts, erythrocyte rosette (ER) and secretory rosette (SR) formation with, and phagocytosis of antigenic rabbit red blood cells} in earthworms after acute exposure to a known mammalian and L. terrestris immunotoxin, the PCB Aroclor 1254.

A Cynara scolymus, popularmente conhecida como alcachofra, é uma planta hepatoprotetora com função colerética e colagoga. O extrato de C.scolymus foi recentemente liberado para a confecção de medicamentos fitoterápicos sem a necessidade de testes toxicológicos específicos, por ser uma planta utilizada há muito tempo e ter eficácia comprovada. Devido à falta de estudos sobre os efeitos dessa planta e por ela ser muito utilizada, o presente estudo visou avaliar os possíveis efeitos imunotóxicos, teratogênicos e de toxicidade geral do extrato seco da Cynara scolymus. O extrato seco da planta foi administrado a ratos Wistar adultos, machos e fêmeas, nas doses de 1, 2 e 4g/Kg, por gavagem, durante 28 dias, de acordo com o protocolo de testes de toxicidade da OECD Organization for Economic Co-operation and Development, para avaliação de toxicidade geral e imunotoxicidade. Foi avaliado o ganho de peso, consumo de alimento e água, os órgãos linfóides e a fenotipagem de suas células; a atividade de fagócitos, as respostas imunes humoral e celular e a atividade proliferativa de linfócitos também foram avaliados. No estudo da teratogenicidade, ratas prenhes receberam as mesmas doses do extrato seco de C.scolymus do 6° ao 19° dia de gestação. Avaliou-se o tamanho, peso, viabilidade e malformações externas dos fetos, bem como procedeu-se à análise óssea e visceral. O presente estudo revelou que o extrato de alcachofra não promoveu toxicidade geral nos ratos adultos tratados subagudamente; por outro lado, o extrato seco de C.scolymus promoveu aumento no peso relativo e celularidade do baço, aumento no peso relativo dos rins, diminuição na celularidade do timo e diminuição no DTH Delayed-type hypersensivity . Apesar disso a análise destes dados em conjunto não permite sugerir efeito imunotóxico dessa planta. O estudo da teratogenicidade mostrou que fêmeas gestantes tratadas com a C.scolymus apresentaram diminuição no ganho de peso; além disso, foi observada diminuição do peso uterino e fetal, menor comprimento fetal e queda do número de fetos vivos por ninhada. Assim, pode-se sugerir que embora a alcachofra não apresente toxicidade geral, nem efeito imunotóxico, não deve ser utilizado durante a gestação, tendo em vista que foi observada toxicidade fetal. / Cynara scolymus, commonly known as artichoke, is popular used as hepatoprotectant, choleretic and colagogue agent. The C.scolymus extrat was recently approved by Brazilian regulatory agency, for production of phytotherapeutic drugs, without toxicological tests, because it has been considered both harmless and effective. Due to lack of toxicological studies and its widely usage, the aim of this study is evaluate the immune system and the teratogenic effects as well as the general toxicity of C. scolymus extracts. Therefore, the extract was administered to adult male and female Wistar rats by gavage at 1, 2 and 4g/Kg doses for 28 days, according to the OECD (Organization for Economic Co-operation and Development) protocols. Body weight gain, food and water consumption, lymphoid organs and their cell phenotype were evaluated as well as the phagocyte analysis, humoural and cellular immune responses, and lymphocyte proliferation. In teratogenic study, pregnant rats received the same doses of C.scolymus extract from the 6th to the 19th gestational day. Fetuses size, weight, viability and external malformations were evaluated and subjected to bone and visceral analysis. The present study showed that C. scolymus extracts did not promote sub-acute toxicity in adult rats; however, the relative spleen weight and it cellularity were increased just as the kidney weight, but the thymus cellularity and DTH (Delayed-type hypersensivity) decreased. None of those results represent immunotoxic effect. The teratogenic study showed a decrease of body weight gain, uterus weight, fetal weight and number of fetuses, in practically all doses of the extract. Thus, these results showed that the C. scolymus extract is not toxic or immunotoxic but should not be used in pregnancy, due to fetal toxicity.

A gripe é causada pelo vírus Influenza e é um problema de saúde pública mundial, que pode levar a problemas sérios em idosos e crianças. O Brasil implantou a vacinação anual contra influenza a partir de 1999, como ação preventiva contra a doença. A vacina é produzida pelo Instituto Butantan e contém três cepas diferentes do vírus Influenza fragmentado para induzir resposta imune adaptativa, com produção de anticorpos específicos e neutralizantes. A literatura tem mostrado que a exposição à xenobióticos com potencial imunossupressor pode comprometer a eficácia de imunizações ativas, como a imunização contra a gripe. Nosso grupo de pesquisa tem mostrado que a exposição à hidroquinona (HQ), um composto tóxico presente em altas concentrações na fumaça do cigarro, prejudica a resposta imune inata e adquirida. Assim, este trabalho avaliou o efeito da exposição à HQ sobre a resposta imune à vacinação contra influenza. Camundongos machos da linhagem C57BL/6 foram diariamente expostos à HQ (2500 ppm) ou PBS, por 1 hora, por nebulização, por um período de 8 semanas. Durante este período, foram imunizados nas semanas 6 e 8 do início das exposições, pela injeção i.m. de 100µL da vacina. Os parâmetros tóxicos e imunológicos foram avaliados 7, 35 e 70 dias após a segunda dose da vacina. A exposição à HQ não alterou o peso corpóreo dos animais e nem causou alterações morfológicas no pulmão, fígado e rins (histologia por H&E); reduziu a frequência de hemácias (11%), hematócrito (14%), hemoglobina (14%) e volume celular (4%); causou estresse oxidativo no baço (citometria de fluxo); aumentou a área dos folículos de células B no baço e linfonodomegalia (histologia por H&E). Em conjunto, os dados aqui obtidos mostram que a exposição à HQ afetou mecanismos envolvidos na gênese da imunidade ativa contra influenza. Assim, os dados deste trabalho mostram mecanismos tóxicos ainda não descritos para a HQ, e ressalta a HQ como um poluente ambiental que deve ser considerado nas avaliações de risco. / The flu is a health problem worldwide which is caused by the Influenza virus and may result in severe illness in infants and the elderly. The annually vaccination against influenza was implemented in Brazil in 1999 as a preventive measure. The vaccine is produced by Butantan Institute and contains three different strains of the inactivated Influenza virus which induce the adaptive immune response along with production of specific and neutralizing antibodies. The literature has shown that exposure to immunosuppressive xenobiotics may compromise the efficacy of active immunizations, such as influenza. Our research group has shown that exposure to hydroquinone (HQ), a toxic constituent of cigarette smoke, impairs both innate and adaptive immune response. Thus, the aim of this work was to evaluate the effects of HQ on the immune response induced by the influenza vaccine. Male C57BL/6 mice were daily exposed to HQ (2500 ppm) or PBS by nebulization, for 1 hour, for 8 weeks. During the exposure period, the animals were vaccinated on weeks 6 and 8 with 100µL of the vaccine. Toxicologic and immunological parameters were assessed 7, 35 and 70 days after boost administration. HQ exposure did not alter body weight and did not cause morphological alterations in the lungs, liver and kidneys (H&E staining); reduced the frequency of erythrocytes (11%), hematocrit (14%), hemoglobin (14%) and cellular volume (4%) and caused oxidative stress on the spleen (Flow Cytometry); increased the area of B cell follicles in the spleen and increased the size of draining lymph nodes (H&E staining). Altogether, these data show that HQ exposure affected mechanisms involved in the genesis of the adaptive immune response. Thus, the data presented in this work show toxic mechanisms of HQ that have not yet been described, and it also points out HQ as an environmental pollutant which should be considered on risk assessments.

A Cynara scolymus, popularmente conhecida como alcachofra, é uma planta hepatoprotetora com função colerética e colagoga. O extrato de C.scolymus foi recentemente liberado para a confecção de medicamentos fitoterápicos sem a necessidade de testes toxicológicos específicos, por ser uma planta utilizada há muito tempo e ter eficácia comprovada. Devido à falta de estudos sobre os efeitos dessa planta e por ela ser muito utilizada, o presente estudo visou avaliar os possíveis efeitos imunotóxicos, teratogênicos e de toxicidade geral do extrato seco da Cynara scolymus. O extrato seco da planta foi administrado a ratos Wistar adultos, machos e fêmeas, nas doses de 1, 2 e 4g/Kg, por gavagem, durante 28 dias, de acordo com o protocolo de testes de toxicidade da OECD Organization for Economic Co-operation and Development, para avaliação de toxicidade geral e imunotoxicidade. Foi avaliado o ganho de peso, consumo de alimento e água, os órgãos linfóides e a fenotipagem de suas células; a atividade de fagócitos, as respostas imunes humoral e celular e a atividade proliferativa de linfócitos também foram avaliados. No estudo da teratogenicidade, ratas prenhes receberam as mesmas doses do extrato seco de C.scolymus do 6° ao 19° dia de gestação. Avaliou-se o tamanho, peso, viabilidade e malformações externas dos fetos, bem como procedeu-se à análise óssea e visceral. O presente estudo revelou que o extrato de alcachofra não promoveu toxicidade geral nos ratos adultos tratados subagudamente; por outro lado, o extrato seco de C.scolymus promoveu aumento no peso relativo e celularidade do baço, aumento no peso relativo dos rins, diminuição na celularidade do timo e diminuição no DTH Delayed-type hypersensivity . Apesar disso a análise destes dados em conjunto não permite sugerir efeito imunotóxico dessa planta. O estudo da teratogenicidade mostrou que fêmeas gestantes tratadas com a C.scolymus apresentaram diminuição no ganho de peso; além disso, foi observada diminuição do peso uterino e fetal, menor comprimento fetal e queda do número de fetos vivos por ninhada. Assim, pode-se sugerir que embora a alcachofra não apresente toxicidade geral, nem efeito imunotóxico, não deve ser utilizado durante a gestação, tendo em vista que foi observada toxicidade fetal. / Cynara scolymus, commonly known as artichoke, is popular used as hepatoprotectant, choleretic and colagogue agent. The C.scolymus extrat was recently approved by Brazilian regulatory agency, for production of phytotherapeutic drugs, without toxicological tests, because it has been considered both harmless and effective. Due to lack of toxicological studies and its widely usage, the aim of this study is evaluate the immune system and the teratogenic effects as well as the general toxicity of C. scolymus extracts. Therefore, the extract was administered to adult male and female Wistar rats by gavage at 1, 2 and 4g/Kg doses for 28 days, according to the OECD (Organization for Economic Co-operation and Development) protocols. Body weight gain, food and water consumption, lymphoid organs and their cell phenotype were evaluated as well as the phagocyte analysis, humoural and cellular immune responses, and lymphocyte proliferation. In teratogenic study, pregnant rats received the same doses of C.scolymus extract from the 6th to the 19th gestational day. Fetuses size, weight, viability and external malformations were evaluated and subjected to bone and visceral analysis. The present study showed that C. scolymus extracts did not promote sub-acute toxicity in adult rats; however, the relative spleen weight and it cellularity were increased just as the kidney weight, but the thymus cellularity and DTH (Delayed-type hypersensivity) decreased. None of those results represent immunotoxic effect. The teratogenic study showed a decrease of body weight gain, uterus weight, fetal weight and number of fetuses, in practically all doses of the extract. Thus, these results showed that the C. scolymus extract is not toxic or immunotoxic but should not be used in pregnancy, due to fetal toxicity.

No description available.

Copper exposures of 400 μg/L for 5,10 and 15 days resulted in no significant differences in antibody titers of largemouth bass, Micropterus salmoides injected with Aeromonas hydrophila compared to control-injected bass. Twenty days of exposure did significantly increase titers. The control group had significantly lower antibody titers than either control-injected or copper-exposed.

No description available.

Pneumonic pasteurellosis is a significant disease in beef production medicine. The most recent information suggests that this disease is a $700 million dollar per year economic burden in bovine food animal production The medical and pathological characteristics of this disease are well documented. Many pathological findings associated with pneumonic pasteurellosis may be explained by disruption of the pulmonary vascular adrenergic system. However, only a limited amount of research has addressed the adrenergic system and its relationship to the etiology and pathophysiology of this disease. In an attempt to further investigate the contributions of the vascular adrenergic receptor mechanism to the development of pneumonic pasteurellosis a series of six experiments have been completed. It is to be noted, that in 1999 the organism Pasteurella haemolytica was renamed Mannheimia haemolytica. The name change was based on the taxonomic features of the organism from other closely related organisms, in particular Pasteurella multocida.. The differences noted were identified and described by Dr. Mannheim in 1974. The familiarity of the past nomenclature and the lack of familiarity for the new nomenclature suggests that the more commonly recognized name of Pasteurella haemolytica should be used throughout this document. Scientific evidence suggests that the disruption of the normal homeostatic mechanisms of the pulmonary vasculature to beta adrenergic agents may be part of the etiology of pneumonic pasteurellosis. The dynamics and kinetics of the involvement of the beta receptors, following prophylactic vaccination and in the disease state, has yet to be fully investigated with respect to the events associated with pneumonic pasteurellosis. Evaluation of the time frame of the onset and duration of the events associated with the disruption of pulmonary vascular beta adrenergic receptor mechanisms revealed that an escalating level of dysfunction occurs over the first 24-48 hour period after exposure to parenteral Pasteurella haemolytica and lasts for at least 21 days. A component of P.haemolytica organism or contained in the vaccine using the organism is likely associated with the disruption of vascular beta adrenergic mechanism. This factor is, as yet, not specifically identified, however the likely culprit is the lipid A moiety of the endotoxin. Using the well defined and purified Escherichia coli endotoxin, trials were run to examine the effect of endotoxin on the pharmacological response of vascular associated beta adrenergic receptor mechanisms. The effects of Escherichia coli endotoxin, administered parenterally, on beta adrenergic receptor mechanisms were pharmacologically indistinguishable from those effects following parenterally administered Pasteurella haemolytica. The nature of the disruption in the beta adrenergic receptor remains a mystery. The receptor mechanism involves at least two second messengers to initiate vascular relaxation. Initial activation of the beta adrenergic receptor with a beta selective drug starts a cascade of events involving adenylylate cyclase and cyclic adenylylate monophosphate (cAMP) and nitric oxide. A disruption in the receptor mechanism, as a result of the parenteral administration of Pasteurella haemolytica, which is "upstream" of adenylyl cyclase, would result in a diminished amount of cAMP when compared to the unvaccinated negative controls. An investigation of cAMP accumulation, at the receptor level was inconclusive. The assessment of some previously used vaccines has demonstrated that there is an, as yet unidentified virulence factor, associated with these vaccines that results in the pharmacological disruption of beta adrenergic receptor mechanisms. Two newer vaccines, Once PMH® and One Shot® have been evaluated and there is evidence to suggest that these currently used vaccines also have the ability to disrupt beta adrenergic receptor mechanisms in rats. The effects of parenteral P. haemolytica on the alpha-2 adrenergic receptor mechanism, is described. The alpha-2 receptor mechanism, unlike the beta receptor mechanism appears to increase the amount of vasoconstriction. The possibility that the alpha-2 adrenergic receptor could also mediate vasorelaxation under certain conditions was investigated. The evidence suggests that in the presence of high alpha-1 mediated vascular tone, the alpha -2 receptor can cause vasorelaxation. Evidence, from other scientists active in this area of investigation, suggests that a vasorelaxation response may be mediated by nitric oxide. Elimination of the nitric oxide mediated relaxation may offer an explanation for the increased vasoconstriction noted with alpha-2 selective drugs after exposure to parenteral P. haemolytica. Finally, the importance of the beta adrenergic receptor to the disease process is addressed by elucidation of one of the mechanisms by which Micotil 300® (tilmicosin phosphate) acts to improve cattle with symptomatic pneumonic pasteurellosis. The rapid improvement of animals on Micotil 300®, with-in 24 hours suggests that there is a mechanism beyond the antimicrobial effect of the drug that mediates the clinical improvement. Evaluation of the effect of Micotil 300® demonstrates a pharmacologically measurable amount of beta adrenergic activity with respect to the bovine pulmonary artery and vein. Based on the conclusions drawn as a result of these experiments, the adrenergic system in general, and the beta adrenergic system in particular are important to the development of pneumonic pasteurellosis in cattle. The beta adrenergic system is affected by endotoxin. Further, these receptors maybe responsible for the mediation of the pathological and clinical signs associated with pneumonic pasteurellosis. In conclusion, these investigations have suggested, that it is likely that a disruption in the homeostatic mechanisms mediated by the beta and alpha-2 adrenergic receptors are intimately involved in the development of post vaccination receptor failure as well as the pathophysiology associated with pneumonic pasteurellosis in cattle. / Ph. D.

A bacterial challenge assay was developed utilizing the earthworm, Lumbricus terrestris, in order to assess potential immunotoxic effects from exposure to specific polychlorinated biphenyl congeners. Earthworms were inoculated with Aeromonous hydrophila, establishing a 10-day LD50. In vitro assays for effects of PCBs on phagocytosis agreed with mammalian studies, demonstrating potent suppression of phagocytosis by the non-coplanar PCB congener 138 and no suppression by the coplanar congener 126. However, when the effects of the two PCB congeners were evaluated for suppression of resistance to a whole animal infection challenge assay, coplanar PCB 126 decreased the ability of L. terrestris to withstand infection while non-coplanar PCB 138 did not.

Electrospun materials have potential use in many biomedical applications such as soft tissue replacements or as scaffolds to target drug delivery to local sites. Electrospinning is a polymer processing technique that can be used to create materials composed of fibers with diameters ranging from the micron to the nanoscale. We investigated the effects of microfibrous and nanofibrous electrospun polycaprolactone (EPCL) on innate, cell-mediated, and humoral components of the immune system. Results demonstrated that in both young (12 week) and old (6 month) mice, EPCL had no effect on various immune parameters. With its lack of immunotoxicity, EPCL presents an excellent polymer scaffold for use in delivering drugs to local sites. Drug delivery studies focused on using EPCL nanofiber scaffolds with the known immunosuppressive compound dexamethasone (DEX) incorporated within the matrix. The ability of the EPCL-DEX scaffold to suppress cell-mediated immunity (CMI) was evaluated using the delayed-type hypersensitivity (DTH) response to Candida albicans. Preliminary studies were conducted following subcutaneous implantation of a single disk (6-mm or 3-mm diameter) with 3, 10, 30, or 100 % w/w DEX in EPCL in the thigh region. Based on footpad swelling, dose -responsive suppression of the DTH was observed based on DEX equivalent units (DEU) at all but the lowest dose. The animals that received the high dose (100% in 6-mm) had decreased spleen weights, however no change in spleen weight was observed at the lower doses. Thymus weights were only affected at the four highest doses. These preliminary results suggest that implantation of a drug-containing electrospun scaffold may achieve local immunosuppression without systemic toxicity. Finally, we evaluated the EPCL-DEX scaffold in an acute inflammatory model (keyhole limpet hemocyanin) and a mouse model of rheumatoid arthritis (collagen induced arthritis). While similar trends were observed in the other models, the EPCL-DEX system achieved greatest success in the DTH model.