A Artrite Reumatóide (AR) é uma artropatia autoimune multifatorial com etiologia desconhecida que afeta aproximadamente 1% da população adulta. A estratégia padrão para o tratamento da AR consiste na administração de baixas doses de Metotrexato (MTX), cujo efeito anti-inflamatório está relacionado com a manutenção dos níveis elevados de adenosina (ADO) extracelular. No entanto, uma parte considerável dos pacientes com AR é refratária ao tratamento com MTX e o mecanismo pelo qual este fenômeno ocorre ainda não está totalmente esclarecido. Neste contexto, o presente estudo descreveu que a eficácia terapêutica ao MTX está associada com a expressão em células Tregs da ectoenzima CD39, cuja função biológica é a geração de ADO extracelular via metabolização do ATP. Especificamente, através da realização de um estudo longitudinal, observamos que pacientes respondedores ao MTX (R-MTX) apresentam uma expansão de células Tregs circulantes expressando CD39 após o tratamento com MTX. Por outro lado, identificamos que pacientes não respondedores ao MTX (UR-MTX) possuem uma redução da expressão de CD39 em células Tregs, o que culmina em um comprometimento das suas funções supressoras. Ainda, demonstramos que a expressão de CD39 em células Tregs é um biomarcador apto em predizer a resposta terapêutica ao MTX, visto que pacientes UR-MTX apresentam uma expressão reduzida de CD39 em Tregs mesmo antes do início do tratamento com MTX. Posteriormente, nós investigamos as bases moleculares que acarretam na expressão reduzida de CD39 observada em células Tregs de pacientes URMTX. Demonstramos que a estimulação com TGF-? tanto em células Tregs isoladas quanto diferenciadas in vitro aumenta a expressão de CD39 através da ativação sequencial da seguinte plataforma molecular: receptores de TGF-? (TGFBRII e TGFBRI), transdutor de sinal SMAD2, fator de transcrição CREB, de modo dependente da atividade de p38. Uma vez identificada a via envolvida com a indução da expressão de CD39, demonstramos que células Tregs diferenciadas de indivíduos que apresentam uma expressão reduzida de CD39 são incapazes de induzir a expressão desta ectoenzima através da estimulação com TGF-?. Por fim, transpondo nossos achados para pacientes com AR, observamos que pacientes UR-MTX apresentam uma redução nos níveis de RNAm para TGFBRII e CREB bem como também uma redução das proteínas fosforiladas SMAD2 e CREB em células CD4+ e Tregs, sugerindo que o comprometimento na cascata de sinalização de TGF-?, envolvida com a indução da expressão de CD39 em células Tregs, está associado com a resistência ao MTX. / Rheumatoid arthritis (RA) is an autoimmune multifactorial arthropathy with unknown etiology that affects approximately 1% of the adult population. The standard strategy for RA treatment comprises the administration of low doses of methotrexate (MTX), whose antiinflammatory effects are associated with maintenance of high levels of extracellular adenosine (ADO). However, a considerable proportion of RA patients is resistant to MTX treatment and the mechanisms underlying this phenomenon occurs is poorly understood. Within this context, the present study showed that therapeutic efficacy of MTX is associated with expression on Treg cells of the ectoenzyme CD39, whose function is related to the generation of extracellular ADO by ATP metabolism. Specifically, we conducted a longitudinal study and observed that responsive patients to MTX (R-MTX) exhibit an increase in the frequency of circulating Treg cells expressing CD39 after MTX treatment. On the other hand, we found that non-responsive patients to MTX (UR-MTX) have a reduction of CD39 expression on Treg cells, which culminates in an impairment of Treg function. Furthermore, these findings indicate that CD39 expression on Treg cells is a biomarker for therapeutic response to MTX, since UR-MTX patients had a depressed CD39 expression on Treg cells even before MTX treatment. Subsequently, the present study investigated the molecular mechanisms that would cause the reduction of CD39 expression on Treg cells from UR-MTX patients. For this, we demonstrated that TGF-? stimulation increases CD39 expression in isolated and in vitro differentiated Treg cells through participation/activation of the following molecules: receptors of TGF-?, TGFBRII and TGFBRI, signal transducer SMAD2 and transcription factor CREB, through p38 activity dependent-manner. Once identified these molecules involved with CD39 induction, we demonstrated that differentiated Treg cells from healthy individuals with an intrinsic reduction of CD39 expression on circulating Treg cells are unable to increase CD39 expression by TGF-? stimulation. Transposing our findings to RA patients, we found that UR-MTX patients exhibit a reduction of mRNA for TGFBRII and CREB as well as reduction on levels of phospho-SMAD2 and phospho-CREB in CD4+ and Treg cells, suggesting that an impairment in TGF-? signaling pathway, related to induction of CD39 expression on Treg cells, is associated with MTX resistance.

Orientadores: José Andrés Yunes, Ana Carolina de Mattos Zeri / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T13:46:58Z (GMT). No. of bitstreams: 1 Canevarolo_RafaelRenatino_M.pdf: 3376497 bytes, checksum: f3e8edf217e0d57089ffcffbe4a8097a (MD5) Previous issue date: 2012 / Resumo: O uso intensivo e combinado de diferentes quimioterápicos tem permitido a cura de 70-80% das leucemias linfóides agudas (LLA) da infância, sendo que a recaída da doença decorre em grande parte da resistência intrínseca das células leucêmicas à quimioterapia. Alguns dos quimioterápicos utilizados na LLA são inibidores metabólicos, como o metotrexato (MTX), antagonista do ácido fólico, que impede a divisão celular ao inibir a síntese de nucleotídeos. Em uma abordagem metabolômica, foi investigada a associação entre linhagens leucêmicas resistentes ou sensíveis ao MTX e metabólitos biondicadores de cada um destes fenótipos. Seis linhagens celulares B-derivadas e oito T-derivadas foram classificadas como sendo resistentes ou sensíveis ao MTX pelo método do 3-(4,5-dimetiltiazol-2il)-2,5-difenil brometo de tetrazolina (MTT) após 48h de co-cultura com diferentes concentrações da droga. Cinco linhagens foram classificadas como resistentes e nove como sensíveis ao MTX. Após 24h de cultura na presença ou ausência de MTX (ambos em triplicata), os metabólitos intracelulares das linhagens foram acessados por ressonância magnética nuclear (RMN) numa abordagem metabolômica. Ao total, oitenta e quatro metabólitos foram quantificados, dos quais 72 foram também identificados. A análise de componentes principais (PCA) não conseguiu segregar as amostras de acordo com sua resistência, ao passo que a análise discriminante por mínimos quadrados parciais (PLS-DA) foi efetiva nesta separação. Os metabólitos mais relevantes para a construção dos modelos de classificação quanto à resistência ao MTX, tanto para amostras tratadas quanto controles foram: ATP, dimetilglicina, fosfocolina e sarcosina (associados à resistência); carnitina, CB-09 (composto não identificado), colato, fumarato, glicocolato, lactato, malato e succinato (associados à sensibilidade ao MTX). A capacidade de classificar corretamente as amostras em sensíveis ou resistentes foi obtida com a construção de curvas da característica operativa do receptor (ROC) para os metabólitos individualmente. Os metabólitos com desempenho bom ou excelente na análise ROC (AUC>0,8) foram selecionados para comporem "testes diagnósticos" de classificação de amostras. De todas as combinações possíveis dentre os metabólitos selecionados, o teste que considerou a combinação de carnitina, sarcosina e succinato em amostras não tratadas com MTX apresentou sensibilidade de 100% (identificou todas as 15 amostras resistentes) e especificidade de 92,3% ao classificar corretamente 24 de 26 amostras sensíveis. O melhor teste diagnóstico para amostras tratadas com MTX considerou as concentrações de CB-MTX, glicocolato, sarcosina e succinato; apresentou sensibilidade de 100% (identificou as 15 amostras resistentes) e especificidade de 85,2%, equivocando-se na classificação de 4 dentre 27 amostras sensíveis. As concentrações metabólicas diferenciais apontaram para uma superativação dos metabolismos energético e de lipídeos em linhagens sensíveis ao MTX, ao passo que linhagens resistentes teriam superativado o metabolismo da glicina. As análises metabolômicas e de integração bioquímica dos metabólitos revelaram interações gênicas, enzimáticas e metabólicas que podem estar alteradas em linhagens sensíveis ou resistentes ao MTX, bem como permitiram a especulação sobre possíveis alvos moleculares que poderiam tornar sensíveis células resistentes ao quimioterápico / Abstract: The intensive use of different and combined chemotherapics has allowed curing 70-80% of pediatric acute lymphoblastic leukemia (ALL), and the relapse of the disease stems largely from the intrinsic resistance of leukemic cells to chemotherapy. Some of the chemotherapics used in ALL are metabolic inhibitors such as methotrexate (MTX), a folic acid antagonist, which prevents cell division by inhibiting the synthesis of nucleotides. The association between leukemic strains resistant or sensitive to MTX and the metabolites associated with each of these phenotypes were investigated. Six B- and eight T-derived cell lines were classified as resistant or sensitive to MTX by the 3-(4,5-Dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT) assay, after 48h in co-culture with different concentrations of the drug. Five lineages were classified as resistant, and nine as sensitive to MTX. After 24 hours of culture in the presence or absence of MTX (both in triplicates), the intracellular metabolites of the lineages were assessed by nuclear magnetic resonance (NMR), in a metabolomic approach. In total, 84 metabolites were quantified, 72 of which were also identified. The principal component analysis (PCA) did not segregate the samples according to their resistance, whereas the supervised partial least square discriminate analysis (PLS-DA) was effective in this separation. ATP, dimethylglycine, sarcosine and phosphocholine were associated with MTX resistance in both models constructed for treated and untreated samples, whereas carnitine, CB-MTX (unidentified compound), cholate, fumarate, glycocholate, lactate, malate and succinate were associated with sensitivity to MTX. The ability to correctly classify the samples into sensitive or resistant groups was checked with the construction of the receiver operating characteristic (ROC) curves for metabolites individually. Metabolites with good or excellent performance in ROC analysis (AUC> 0.8) were selected to compose "diagnostic tests" for classifying samples. Of all the possible combinations among the selected metabolites, the test composed by the comination of carnitine, sarcosine and succinate in untreated samples exhibited sensitivity of 100% (identified all 15 resistant samples) and specificity of 92.3% in classifying correctly 24 of 26 sensitive samples. The best diagnostic test for samples treated with MTX took into consideration concentrations of CB-MTX, glycocholate, sarcosina, succinato. It had a sensitivity of 100% (identified 15 resistant samples) and specificity of 85.2%, classifying incorrectly 4 out of 27 sensitive samples. Differential metabolic concentrations pointed to an over activation of energy and lipids metabolism in MTX-sensitive strains, whereas resistant strains seemed to have overactive the glycine metabolism. Metabolomic and biochemical integration analysis revealed genetic, enzymatic and metabolic interactions that might be altered in strains sensitive or resistant to MTX, as well as allowed speculations about possible molecular targets on which intervention could make resistant cells susceptible to chemotherapy / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas

Charles University, Faculty of Pharmacy in Hradec Králové Department of pharmacology and toxicology Candidate: Bc. Petra Vicherková Supervisor: prof. PharmDr. Petr Pávek, Ph.D. Title of master thesis: Pharmacogenetics in rheumatology - role of miRNA Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disease that causes progressive joint damage and can result in to life-long depreciation of life. The influence on the onset and course of the disease is not only genetic, but due to the heterogeneous character of the disease, it is also strongly influenced by lifestyle. This disease, based on the malfunction of our immune system in RA, is still incurable. The treatment of RA uses conventional synthetic drugs as well as biological treatment. To diagnose the effect of anti-rheumatic therapy, monitoring and evaluating the response to treatment is necessary. Important indicators of RA activity, functional status, quality of life, and structural progression of the disease are important. In clinical practice, we use DAS 28 composite system according to recommendation of ČRS. Recent discoveries in the area of diagnostics raise the question of whether some miRNAs could be appropriate biomarkers of RA progression. In my diploma thesis, I summarize available knowledge in this field, obtained from...

Orientadores: José Andrés Yunes, Nilson Ivo Tonin Zanchin / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T06:00:33Z (GMT). No. of bitstreams: 1 Silveira_AndreBortolini_D.pdf: 16883235 bytes, checksum: e0759c48520d471791a5272349e1a837 (MD5) Previous issue date: 2013 / Resumo: A via PI3K está frequentemente hiperativada em células primárias de leucemia linfoide aguda T (LLA-T) pediátrica, característica previamente associada à resistência a glucocorticoides. Pacientes cujas células leucêmicas apresentam mutações em PTEN, o principal regulador negativo de PI3K, podem apresentar maior risco de falha na terapia de indução e recaída. Neste estudo, uma assinatura baseada em expressão gênica foi utilizada para acessar o nível de ativação da via PI3K em amostras diagnósticas de LLA-T. Nós identificamos Myc como um importante integrador da atividade de sinalização por PI3K e observamos que maior atividade da via está associada à resistência a glucocorticoides e pior prognóstico. O inibidor de PI3K AS605240 mostrou atividade antileucêmica e forte sinergismo com glucocorticoides tanto in vitro como em um modelo xenográfico de LLA-T em camundongos NOD/SCID. Em contraste, a inibição de PI3K resultou em antagonismo com metotrexato e daunorrubicina, drogas que atuam preferencialmente em células em divisão. Esta interação antagonística, no entanto, pôde ser revertida pelo uso de um esquema temporal específico de administração das drogas. Nossos dados indicam os potenciais benefícios e limitações para a incorporação de inibidores de PI3K na terapia da LLA-T / Abstract: The PI3K pathway is frequently hyperactivated in primary T-cell acute lymphoblastic leukemia (T-ALL) cells. Activation of the PI3K pathway has been suggested as one mechanism of glucocorticoid resistance in T-ALL, and patients harboring mutations in the PI3K negative regulator PTEN may be at increased risk of induction failure and relapse. In this study, a PI3K gene expression signature was used as readout of PI3K activity in diagnostic T-ALL samples. We identified Myc as an important downstream integrator of PI3K pathway activity in T-ALL and found that higher PI3K activity is associated with glucocorticoid resistance and worse clinical outcome. The PI3K inhibitor AS605240 showed anti-leukemic activity and strong synergism with glucocorticoids both in vitro and in a NOD/SCID xenograft model of T-ALL. In contrast, PI3K inhibition showed antagonism with methotrexate and daunorubicin, drugs that preferentially target dividing cells. This antagonistic interaction, however, could be circumvented by the use of correct drug scheduling schemes. Our data indicate the potential benefits and difficulties for the incorporation of PI3K inhibitors in T-ALL therapy. OBSERVAÇÃOArquivo pdf com capa, página de rosto, folha de assinatura da banca examinadora, resumo e abstract foi editado segundo informação CCPG/002/2013 / Doutorado / Genetica Animal e Evolução / Doutor em Genetica e Biologia Molecular

O Metotrexato (MTX) é utilizado em altas doses no tratamento de neoplasias e em baixas doses como antiinflamatório. O objetivo deste estudo foi avaliar a reparação da fratura de côndilo mandibular e a simetria facial em ratos tratados com MTX. Foram utilizados 100 ratos, Wistar, machos que foram submetidos a procedimento cirúrgico utilizando modelo experimental de fratura de côndilo do lado direito. Os ratos foram distribuídos em quatro grupos e receberam os seguintes tratamentos: Controle - soro (um mL/semana); Dexametasona - dexametasona (0,15 mg/Kg); MTX Baixa dose - MTX (três mg/kg/semana); MTX Alta dose - MTX (30 mg/Kg). Os períodos de sacrifício foram de um dia, sete, 15, 30 e 90 dias de pós-operatório (n=cinco). O peso dos animais foi documentado. Foi realizada coleta de sangue para análise bioquímica de proteínas totais e fosfatase alcalina. Foi realizado exame radiográfico das cabeças em norma axial para análise cefalométrica. Foram realizadas mensurações lineares da maxila e mandíbula, bem como angulares do desvio mandibular. As amostras foram processadas histologicamente sendo obtidas lâminas com cortes no sentido coronal. Os dados quantitativos foram submetidos a análises estatísticas (=0,05). Os animais recuperaram peso ao longo do tempo, exceto no grupo MTX Alta dose. Os níveis séricos de proteínas totais mostraram aumento nos períodos iniciais e os de fosfatase alcalina queda nos períodos de formação do calo ósseo no tratamento com MTX. Houve redução no comprimento mandibular com alterações também na maxila e desvio progressivo da mandíbula em relação à base do crânio no grupo MTX Alta dose. A análise histológica revelou que houve reparo da fratura, pela formação de calo ósseo, e das estruturas da articulação sendo que no grupo MTX Alta dose ocorreu um retardo neste processo, havendo desvio do côndilo e em um espécime houve anquilose fibrosa. A histomorfometria revelou que a área de neoformação óssea foi menor no grupo MTX Alta dose. Foi concluído que o tratamento com MTX em alta dose teve efeito deletério na simetria facial de ratos submetidos à fratura do processo condilar e prejudicou a formação do calo ósseo e o reparo da articulação temporomandibular, com possível indução de anquilose fibrosa. / low doses as an antiinflammatory. The aim of this study was to evaluate the healing of the mandibular condyle fracture and facial symmetry in rats treated with MTX. 100 Wistar male rats undergone surgery using an experimental model of mandibular condyle fracture of the right side. The rats were distributed in four groups and received the following treatments: Control Saline (1 ml/week); Dexamethasone dexamethasone (0,15mg/kg); MTX Low dose MTX (3 mg/kg/week); MTX High dose MTX (30 mg/kg). Animals were sacrificed at one, seven, 15, 30 and 90 days postoperatively (n=5). Animals body weight were recorded. Blood has been taken to provide the biochemical analysis of total proteins and alkaline phosphatase. Radiographic axial exams from the heads were provided to cephalometric analysis. Linear measures of jaw and mandible, as well as angular measures of the mandibular deviation were done. The samples were histologically processed and coronal sections were obtained. Quantitative data were submitted to statistical analysis (=0,05). The animals regained body weight over the time, except in MTX High dose group. Total protein serum levels demonstrated the increase in initial periods and the alkaline phosphatase levels showed decrease in the periods of bone callus formation. There was reduction in the mandibular length and also changes in the jaw and progressive deviation in the mandible in relation to the skull basis in the MTX High dose group. The histological analysis revealed that there were repair of the bone and temporomandibular joint although in the MTX High dose group there was a delay in this process, in wich there was deviation of the condyle and one specimen was fibrous ankylosis. Histomorphometry revealed that the new bone formation area was lower in MTX High dose group. It was concluded that treatment with high dose MTX had a deleterious effect on facial symmetry of rats submitted to fracture of the condylar process and damaged the bone callus formation and repair of the temporomandibular joint, with possible induction of fibrous ankylosis.

<p>Insects are continually exposed to potentially toxic endogenous compounds and xenobiotics that require rapid elimination from the body. Xenobiotic resistance in insects has evolved predominantly by increasing the activity of detoxification enzymes and/or by increasing toxin excretion via the Malpighian (renal) tubules. The tubules have long been known to transport organic anions at high rates. This thesis examines the mechanisms of excretion and detoxification of the organic anion methotrexate (MTX) by isolated tissues of the fruit fly <em>Drosophila melanogaster</em>. A radioisotope tracer technique and the Ramsay assay were used to measure MTX secretion. Quantitative PCR (qPCR) was used to evaluate the expression of the genes for putative organic anion transporters. My results show that MTX transport across the Malpighian tubule epithelium is active, saturable, Na⁺-independent and inhibited by a wide range of organic anions including MK-571, probenecid and Texas Red. Pharmacological studies and qPCR analyses suggest multiple transporters are involved in the movement of MTX across the Malpighian tubules. Moreover, chronic exposure of larvae to dietary MTX or salicylate dramatically increases the transepithelial transport of MTX by isolated Malpighian tubules, suggesting that excretion of MTX is upregulated by exposure to these organic anions in the diet. In addition, treatments known to increase expression of specific detoxification enzymes, such as the P450 monoxygenases (P450s) and the glutathione-S-transferases (GSTs), also led to an increase in expression levels of multidrug efflux transporter (MET), multidrug resistance like protein 1 (dMRP) as well as to increased secretion of MTX by the tubules. This latter finding suggests a coordinated response to toxin exposure, so that when detoxification pathways are increased, there is a corresponding increase in the capacity for elimination of the products of P450 and GST enzymes. Finally, the last section of this thesis has shown that RNAi knockdown of a single organic anion transporter gene in the principal cells of <em>D. melanogaster</em> Malpighian tubules is associated with reductions in the expression of multiple, functionally-related genes. Importantly, these results indicate that dMRP andMET are not the dominantMTX transporters in the tubules when flies are reared onMTX-enriched diets. However, reductions in the expression of organic anion transporting polypeptide (OATP) are associated with reduced secretion of the organic anionsMTX, fluorescein and Texas Red. Taken together, these results suggest that OATP and at least one additional transporter, as yet unidentified, are required forMTX secretion. In conclusion, the results of my research contribute to our understanding of the mechanisms of organic anion detoxification and excretion in flies exposed to dietary toxins.</p> / Doctor of Science (PhD)

Introdução: A doença vascular do coração transplantado, consiste em um processo inflamatório proliferativo que compromete o sucesso a longo prazo do transplante cardíaco e não há prevenção ou tratamentos efetivos. Uma nanoemulsão lipídica (LDE) pode carregar agentes quimioterápicos na circulação e concentrá-los nos enxertos cardíacos dos coelhos. O objetivo deste estudo foi investigar os efeitos do paclitaxel combinado a LDE;do metotrexate combinado ao LDE e a associação de ambos quimioterápicos ao LDE nos corações transplantados. Método: 28 coelhos alimentados com dieta com teor de 0,5% de colesterol e submetidos a transplante cardíaco herotópico foram tratados com ciclosporina (dose 10 mg/kg/ dia por via oral) e alocados em 4 grupos de 7 animais.Um grupo recebeu a associação de Metotrexate e LDE endovenosa (4 mg/kg/semana); segundo grupo recebeu por via endovenosa a combinação de Paclitaxel e LDE; o terceiro grupo recebeu a associação de LDE com metotrexate e paclitaxel; grupo controle que recebeu somente solução salina intravenosa. Os animais foram sacrificados 6 semanas após o procedimento. Foram realizadas análises da morfologia,histologia,imunohistoquímica e análise da expressão gênica do enxerto e dos corações nativos. Resultado: Em comparação com o grupo controle,coelhos transplantados e tratados com paclitaxel associado ao LDE apresentaram redução em 50% de estenose em artérias coronárias. Já nos grupos que usaram metotrexate associado a LDE ou paclitaxel combinado com metotrexate e associado a LDE, houve redução em 18% da estenose coronariana em relação ao grupo controle,mas a diferença não apresentou significância estatística.Nos três grupos tratados, houve redução do infiltrado macrofágico. No grupo que recebeu metotrexate associado a LDE,a expressão gênica de fatores pró-inflamatórios( TNF-alfa; MCP1; IL 18; VCAM-1 e MMP-12) foi reduzida drasticamente; enquanto a expressão de agentes anti-inflamatórios(IL 10 por exemplo) aumentou. Nos outros dois grupos (LDE+paclitaxel e LDE+paclitaxel e metotrexate) não houve influência consistente na expressão de genes pró e anti-inflamatórios. Conclusão: A associação paclitaxel e LDE promoveu melhora importante na vasculopatia dos enxertos.A associação metotrexate e LDE e a metotrexate mais palcitaxel e LDE reduziram a estenose de coronárias porém sem significância estatística. O infiltrado macrofagocítico foi reduzido nos três grupos tratados. Tais resultados podem servir de ponte para novos ensaios clínicos / Background: Coronary allograft vasculopathy is an inflammatory-proliferative process that compromises the long-term success of heart transplantation and currently has no effective prevention and treatment. A lipid nanoemulsion (LDE) can carry chemotherapeutic agentsin the circulation and concentrates them in the heart graft in rabbits. The aim of this study was to investigate the effects of paclitaxel (PACLI) binded tire parentesis to LDE, methotrexate (MTX) binded to LDE and the association of both particles in transplanted heart. Methods: Twenty eight rabbits fed 0,5% cholesterol diet and submitted to heterotopic heart transplantation were treated with cyclosporine A (10mg/kg/daily orally) and allocated to four groups of 7 animals. One group was treated with intravenous LDE-MTX (4mg/kg B.W., weekly); a second with LDE-paclitaxel, the third one with association of LDE-PACLI with LDE-MTX and the control group received only weekly intravenous saline solution. Animals were sacrificed 6 weeks later for morphometric, histological, immunohistochemical and gene expression analysis of the graft and native hearts. Results: Compared to controls, grafts of LDE-PACLI treated rabbits showed 50%reduction of coronary stenosis and in the LDE-MTX and LDE-MTX/PACLIstenosiswas around 18% less than control but this difference was not statistically significant. In the 3 treatment groups macrophage infiltration was decreased. In LDE-MTX group, gene expression of pro-inflammatory factors TNF-?, MCP-1, IL-18 and VCAM-1, and MMP-12 was strongly diminished whereas expression of anti-inflammatory IL-10 increased. In the other two treatment, groups (LDE-PACLI and LDE-PACLI/MTX) there was not a consistent influence in pro and anti-inflammatory gene expression. Conclusions: LDE-PACLI promoted strong improvement of the cardiac allograft vasculopathy. LDE- MTX and LDE -MTX/PACLI decreased coronary stenosis but without statistic significance. Macrophage infiltration was decrease in the three treatment groups. This new preparation maybe candidate for future clinical trials

Em estudos anteriores, mostramos que uma nanoemulsão artificial (NEm) de composição semelhante à da lipoproteína de baixa densidade se liga a receptores de lipoproteínas de baixa densidade após sua injeção na corrente sanguínea. Como tais receptores estão superexpressos em células com altas taxas de proliferação, como ocorre no cancer e na aterosclerose, a NEm pode ser utilizada como veículo para direcionar drogas a estas células, diminuindo sua toxicidade e aumentando sua ação farmacológica. Recentemente, reportamos que a associação de um derivado do agente antiproliferativo paclitaxel, o oleato de paclitaxel (OPTX) à NEm reduziu em 60% a área lesionada de aortas de coelhos submetidos à dieta rica em colesterol. Neste estudo, testamos o efeito sinérgico da terapia combinada do OPTX-NEm com um derivado do metotrexato, o di-dodecil metotrexato (DMTX), também associado à NEm. O MTX, além de sua ação antiproliferativa, também possui propriedades imunossupressoras. Coelhos machos da raça Nova Zelândia foram submetidos à dieta enriquecida com 1% de colesterol durante 8 semanas. A partir da quinta semana de consumo da dieta, 8 animais foram injetados semanalmente com solução salina por via endovenosa (grupo controle) e 8 receberam o tratamento combinado de OPTX-NEm (4mg/Kg) com DMTX-NEm (4mg/Kg), por 4 semanas. Ao final das 8 semanas, os animais foram sacrificados. As aortas dos animais foram retiradas, abertas longitudinalmente, fixadas em formalina tamponada a 10% e coradas com Escarlate R para a análise macroscópica da lesão. Os arcos aórticos foram seccionados em fragmentos de 5mm, embebidos em parafina e os cortes realizados foram corados com hematoxilina-eosina, para a determinação da área das camadas íntima e média. O tratamento combinado de OPTX-NEm com DMTX-NEm reduziu a área das lesões em 82%, em comparação ao grupo controle, e a razão da área da lesão/área total diminuiu de 0,82±0,08 para 0,08±0,06 (p<0,01). Por meio das avaliações da variação do consumo de ração, peso corporal e contagem de leucócitos totais (p>0,05), pode-se afirmar que os tratamentos não apresentaram toxicidade significativa, exceto pela queda na contagem de eritrócitos (p<0,05). Como conclusão, a quimioterapia combinada de OPTX e DMTX associados à NEm como veículo mostrou-se eficaz na redução da área de lesão aterosclerótica em coelhos e a toxicidade relacionada aos fármacos foi nitidamente reduzida. / In previous studies we have shown that an artificial nanoemulsion (NEm) that resemble LDL composition are taken-up by LDL receptors after injection into the bloodstream. As those receptors are upregulated in cells with higher proliferation rates, as occurs in cancer and atherosclerosis, NEm can be used as vehicle to direct drugs against those cells, diminishing toxicity and increasing pharmacological action. Recently, we reported that association of antiproliferative agent paclitaxel derivative, paclitaxel oleate (OPTX) to NEm reduced by 60% the lesion area of cholesterol-fed rabbits. In this study, the combined chemotherapy of OPTX-NEm with a methotrexate derivative, di-dodecil methotrexate (DMTX), also associated with NEm, was tested for synergistic effects. MTX, besides antiproliferative action, has also immunosuppressant properties. Male New Zealand rabbits were fed a 1% cholesterol diet for 60 days. Starting from day 30, 8 animals were treated with 4 weekly I.V. saline solution injections (control group) and 8 with combined OPTX-NEm (4 mg/kg) plus DMTX-NEm (4 mg/kg) for additional 30 days. On day 60, the animals were sacrificed for analysis. Aorta was excised, open longitudinally, placed in 10% buffered formalin and stained in Scarlet R for lesion macroscopic analysis. Segments of 5mm of the aortic arch were embedded in paraffin and sections were taken and stained in hematoxylin-eosin for intima and media area measurement. In comparison with controls, treatment with combined OPTX-NEm plus DMTX-NEm reduced the lesion area by 82% and the lesion/total area ratio was decreased from 0,82±0,08 to 0,08±0,06 (p<0.01). Except for decrease in erythrocyte count (p<0.05), treatments were devoid of significant toxicity, as evaluated by food intake, body weight and leucocyte count (p>0.05). In conclusion, this novel approach consisting in combined chemotherapy of OPTX and DMTX using NEm as a drug-targeting vehicle showed effective lesion area regression in rabbits and marked toxicity reduction.

Une grossesse extra-utérine est une grossesse implantée en dehors de la cavité utérine. Il existe quatre thérapeutiques pour leur prise en charge : l’expectative, le traitement médical par méthotrexate, le traitement chirurgical conservateur (salpingotomie) et le traitement chirurgical radical (salpingectomie). Le choix entre ces 4 traitements repose tout d’abord sur des critères de faisabilité (traitement médical et expectative sont par exemple exclus en cas de rupture tubaire). Ces critères de faisabilité peuvent être résumés par la notion d’activité de la GEU. Cette notion permet de différencier les grossesses extra-utérines peu actives pouvant bénéficier d’un traitement médical des grossesses extra-utérines actives requérant un traitement chirurgical.Chaque traitement présente des avantages et des inconvénients et la principale question toujours en suspens concerne la fertilité après prise en charge d’une GEU. L’essai randomisé DEMETER a donc été conçu pour évaluer l’existence éventuelle d’une différence de fertilité de plus de 20% entre traitement médical et traitement chirurgical conservateur d’une part pour les GEU peu actives et entre traitement chirurgical conservateur et radical d’autre part pour les GEU actives.Il n’y a pas de différence significative de plus de 20% de fertilité deux ans après la prise en charge d’une grossesse extra-utérine que ce soit pour les grossesses peu actives entre traitement médical et traitement chirurgical conservateur ou pour les grossesses actives entre traitement chirurgical conservateur et radical. Par ailleurs, cet essai a aussi permis de conclure à la supériorité, en terme d’échec immédiat, du traitement chirurgical conservateur avec injection postopératoire de méthotrexate par rapport au traitement médical pour la prise en charge des GEU peu actives. La plus grande efficacité du traitement chirurgical conservateur est probablement majorée par l’injection postopératoire de méthotrexate. Le taux de conversion d’un traitement chirurgical conservateur vers un traitement chirurgical radical est important : 10% dans le groupe des GEU peu actives et 21% (significativement plus élevé) dans le groupe des GEU actives. Enfin, Le délai de guérison est plus court après traitement chirurgical conservateur qu’après traitement médical.Ces résultats couplés aux données de la littérature permettent d’élaborer des recommandations sur la prise en charge des grossesses extra-utérines. Notamment, pour les GEU peu actives avec un taux d’hCG inférieur à 5000UI/ml sans signe de rupture tubaire ou de défaillance hémodynamique, un traitement médical par méthotrexate doit être proposé sous réserve d’une bonne compliance de la patiente pour le suivi. Une prise en charge par chirurgie conservatrice reste une option valide. Dans ce cas, une injection postopératoire de méthotrexate sera réalisée systématiquement dans les 24 heures suivant l’intervention. Le traitement des GEU actives est chirurgical et la décision entre conservateur et radical a lieu en peropératoire. Enfin, une information aux patientes pourra être délivrée sur l’absence de différence de fertilité 2 ans après le traitement d’une GEU. / An ectopic pregnancy is a pregnancy implanted outside uterine cavity. There are four different treatments to manage tubal ectopic pregnancy: expectation, medical treatment (methotrexate), conservative surgery (salpingotomy) and radical surgery (salpingectomy). The choice between these different treatments is based on feasibility criteria (medical treatment and expectation are not feasible in case of tubal rupture). These feasibility criteria can be summarized by activity of ectopic pregnancy. This activity allowed differentiating less active ectopic pregnancies that can be supported by medical treatment and active ectopic pregnancies that required surgery.All of these treatments present advantages and disadvantages and the major unresolved issue concerns subsequent fertility after management of ectopic pregnancy. Randomized trial DEMETER has thus been designed to evaluate a difference of 20% between medical management and conservative surgery for less active ectopic pregnancy and between conservative and radical surgery for active ectopic pregnancy. Differences for two years subsequent fertility after management of ectopic pregnancy were not more than 20% between medical management and conservative surgery for less active ectopic pregnancy as between conservative and radical surgery for active ectopic pregnancy. This trial also allowed concluding to the superiority of conservative surgery with a systematic postoperative injection of methotrexate compared to medical treatment for management of less active ectopic pregnancy. This superiority might be enhanced by postoperative methotrexate injection. The conversion rate to radical surgery when a conservative surgery is decided is important: 10% for less active ectopic pregnancy and 21% (significantly higher) for active ectopic pregnancy. Recovery time is shorter after conservative surgery compared to medical management.Results of DEMETER trial and literature review allowed giving guidelines for management of ectopic pregnancy. Less active ectopic pregnancy with hCG rate less than 5.000UI/l without tubal rupture or hemodynamic failure can be managed in first intention by medical treatment (methotrexate) if the women is assiduous to a close check. However, conservative surgery for less active ectopic pregnancy is a good option. A systematic postoperative injection of methotrexate in the 24 first hours after surgery should be recommended. Active ectopic pregnancy has to be managed surgically and decision between conservative and radical surgery should be done in the operative room. Finally, women have to be informed about the absence of difference between treatments for subsequent fertility.

Neural tube defects (NTD) result from the failure of the neural tube to close properly very early in gestation. A child born with an NTD may experience an early death or life-long disability. In the 1990s, the critical role of folic acid in the prevention of NTDs was confirmed and as a strategy to increase blood folate concentrations of women of childbearing age, folic acid fortification programs were mandated in Canada and the US. However, this change impacted the entire population not just women of childbearing age and not everyone may benefit from the increased folate intake. The objective of this research was to investigate the impact of higher intakes of folates on the mortality rates of children with acute lymphoblastic leukemia (ALL) and the risk of colorectal cancer (CRC) in adult populations. To address the impact in children with ALL, a comparison of the mortality rates between the pre- and post-fortification time periods in Ontario was performed using data from the Pediatric Oncology Group of Ontario. A second comparison between the mortality rates in these children in non-folic acid fortifying countries and the US was also completed. These analyses suggest that folic acid fortification is not negatively impacting mortality. With respect to CRC, one systematic review and two meta-analyses were conducted investigating folate intake and the risk of CRC or adenoma recurrence. The first analysis, in observational studies, compared high versus low folate intake and the risk of CRC. The second examined folate intake within the various polymorphisms of the methylene tetrahydrofolate reductase enzyme. The final study examined the impact of supplementation of 1 milligram or more per day of folic acid and the risk of colorectal adenoma recurrence in those adults with a history of colorectal adenomas. The findings from the completed observational studies suggest that there is an associated risk reduction in colorectal cancer from the intake of higher levels of folates. The investigations into the impact of the folic acid fortification program suggest that the program is not associated with having a negative impact on mortality of children with ALL or on the risk of colorectal cancer.