Molluscicide activity of the "Avelós" plant (Euphorbia tirucalli, L. ) on Biomphalaria glabrata, the mollusc vector of schistosomiasis

An aqueous solution of the latex of Euphorbia tirucalli collected at sites receiving large amounts of sunlight showed molluscicide action on Biomphalaria glabrata, with LD50 obtained at the concentration of 28,0 ppm and LD90 at the concentration of 85,0 ppm. The toxicity of the product for fish was similar to that of Bayluscide and of copper sulfate used for comparison. However, the wide distribution of the plant, its easy propagation and the simple procedure for extraction of the active substance, which is biodegradable, favor "avelós" as a promising agent in the control of schistosomiasis.<br>Uma solução aquosa de Euphorbia tirucalli (avelós) coletada em locais ensolarados mostrou atividade moluscicida para Biomphalaria glabrata obtendo-se a LD50 a uma concentração de 28,0 ppm e a LD90 a 85,0 ppm. A toxicidade do produto para peixes foi similar a de Bayluscide e sulfato de cobre testados comparativamente. Pela larga distribuição da planta e sua fácil propagação e extração da substância ativa, e pela ausência de efeito residual, a planta pode ser considerada como promissora para testes de campo em locais restritos

Aptamer delivery of siRNA, radiopharmaceutics and chemotherapy agents in cancer

Submitted by Repositório Arca ([email protected]) on 2019-03-07T16:42:52Z No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) F09-1-s2.0-S0378517317302740-main.pdf: 1028133 bytes, checksum: 737e8f1013224eadc51e5db7dd6ce9bb (MD5)Approved for entry into archive by monique santos ([email protected]) on 2019-03-08T19:35:17Z (GMT) No. of bitstreams: 2 F09-1-s2.0-S0378517317302740-main.pdf: 1028133 bytes, checksum: 737e8f1013224eadc51e5db7dd6ce9bb (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5)Made available in DSpace on 2019-03-08T19:35:17Z (GMT). No. of bitstreams: 2 F09-1-s2.0-S0378517317302740-main.pdf: 1028133 bytes, checksum: 737e8f1013224eadc51e5db7dd6ce9bb (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2017Instituto de Radioproteção e Dosimetria. Comissão Nacional de Energia Nuclear. Laboratório de Radiobiologia. Divisão de Física Médica. Rio de Janeiro, RJ, Brasil.Instituto de Radioproteção e Dosimetria. Comissão Nacional de Energia Nuclear. Laboratório de Radiobiologia. Divisão de Física Médica. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Tecnologia em Imunobiológicos. Rio de Janeiro, RJ, Brasil.Instituto de Radioproteção e Dosimetria. Comissão Nacional de Energia Nuclear. Laboratório de Radiobiologia. Divisão de Física Médica. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Tecnologia em Imunobiológicos. Rio de Janeiro, RJ, Brasil.Aptamers are oligonucleotide reagents with high affinity and specificity, which among other therapeutic and diagnostic applications have the capability of acting as delivery agents. Thus, aptamers are capable of carrying small molecules, nanoparticles, radiopharmaceuticals or fluorescent agents as well as nucleic acid therapeutics specifically to their target cells. In most cases, the molecules may possess interesting therapeutic properties, but their lack of specificity for a particular cell type, or ability to internalise in such a cell, hinders their clinical development, or cause unwanted side effects. Thus, chemotherapy or radiotherapy agents, famous for their side effects, can be coupled to aptamers for specific delivery. Equally, siRNA have great therapeutic potential and specificity, but one of their shortcomings remain the delivery and internalisation into cells. Various methodologies have been proposed to date, including aptamers, to resolve this problem. Therapeutic or imaging reagents benefit from the adaptability and ease of chemical manipulation of aptamers, their high affinity for the specific marker of a cell type, and their internalisation ability via cell mediated endocytosis. In this review paper, we explore the potential of the aptamers as delivery agents and offer an update on current status and latest advancements