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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
891

Estudo alelopático, fitoquímico e genotóxico de extratos aquosos de Aspidosperma pyrifolium Mart. e Combretum leprosum Mart. em Allium cepa / Allelopathic study, phytochemical and genotoxic of aqueous extracts of Aspidosperma pyrifolium Mart. And Combretum leprosum Mart. in Allium cepa

Pereira, José Carlos da Silveira 27 August 2015 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-08-07T21:51:39Z No. of bitstreams: 1 JoséCSP_DISSERT.pdf: 861903 bytes, checksum: 5f78fa00a8f44435ec8fd2bebd231afc (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-08-17T22:38:54Z (GMT) No. of bitstreams: 1 JoséCSP_DISSERT.pdf: 861903 bytes, checksum: 5f78fa00a8f44435ec8fd2bebd231afc (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-08-17T22:40:52Z (GMT) No. of bitstreams: 1 JoséCSP_DISSERT.pdf: 861903 bytes, checksum: 5f78fa00a8f44435ec8fd2bebd231afc (MD5) / Made available in DSpace on 2017-08-17T22:40:59Z (GMT). No. of bitstreams: 1 JoséCSP_DISSERT.pdf: 861903 bytes, checksum: 5f78fa00a8f44435ec8fd2bebd231afc (MD5) Previous issue date: 2015-08-27 / The Caatinga has great plant diversity, but few native species have phytochemical, allelopathic and genotoxic studies. Aspidosperma pyrifolium and Combretum leprosum are examples of plants of great importance ethnopharmacological that lacking of toxicological studies. The objective was to evaluate the allelopathic influence, cytotoxicity and genotoxicity of aqueous extracts of A. pyrifolium and C. leprosum on germination and early development of commercial seed of Allium cepa (indicator organism) and describing their biochemical profiles. 50 seeds of A. cepa were placed in the presence of aqueous extracts of these plants in concentrations of 200, 400 and 800 mg/L, with four replicates each, the following variables were evaluated: germination, germination speed, length and dry matter of roots, hypocotyl and seedling, seedling biomass density and mitotic index. Qualitative and quantitative tests were performed on various classes of metabolites to describe the biochemical profile. The results of the extracts groups did not differ from negative control group, for the germination characteristics, indicating that the extracts do not have allelopathic effect. However, the mitotic index was identified sublethal cytotoxicity of aqueous extract of C. leprosum, with 200 mg/L. Biochemical profiles identified novel substances for both species. However, due to possible synergistic effects of the extracts more studies are needed to better phytochemical characterization of both species / A Caatinga apresenta grande diversidade vegetal, mas poucas espécies nativas possuem estudos fitoquímicos, alelopáticos e genotóxico. Aspidosperma pyrifolium e Combretum leprosum são exemplos de plantas de grande importância etnofarmacológica que carecem de estudos toxicológicos. O objetivo foi avaliar a influência alelopática, citotoxidade e genotoxidade de extratos aquosos de A. pyrifolium e C. leprosum sobre a germinação e desenvolvimento inicial de sementes comerciais de Allium cepa L. (organismo-teste) e descrever seus perfis fitoquímicos. 50 sementes de A. cepa foram colocadas na presença dos extratos aquosos dessas plantas nas concentrações de 200, 400 e 800 mg/L, com quatro réplicas cada, sendo avaliadas as seguites variáveis: germinação, velocidade de germinação, comprimento e matéria seca de raízes, hipocótilo e plântula, densidade de biomassa de plântula e índice mitótico. Foram realizados testes qualitativos e quantitativos em diversas classes de metabólitos para a descrição do perfil fitoquímico. Os resultados dos grupos dos extratos não diferiram estatisticamente do grupo controle negativo, quanto às características germinativas, indicando que os extratos não possuem efeito alelopático. No entanto, pelo índice mitótico foi identificado citotoxidade subletal do extrato aquoso de C. leprosum, com 200 mg/L. Os perfis fitoquímicos identificaram substâncias inéditas para ambas as espécies. Entretanto, devido a possíveis efeitos sinergéticos dos extratos são necessários mais estudos para melhor caracterização fitoquímica de ambas as espécies / 2017-08-07
892

Avaliação tóxica, citotóxica e mutagênica de extratos aquosos de Ipomoea asarifolia (Convolvulaceae) / Toxic, cytotoxic and mutagenic evaluation of aqueous extract of Ipomoea asarifolia (Convolvulacea)

Silva Filho, Eliezer Fernandes da 11 February 2015 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-08-08T21:47:01Z No. of bitstreams: 1 EliezerFSF_DISSERT.pdf: 825442 bytes, checksum: 4e1f858f4401bb5bd1feb35cb8a2ae1e (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-08-17T22:39:18Z (GMT) No. of bitstreams: 1 EliezerFSF_DISSERT.pdf: 825442 bytes, checksum: 4e1f858f4401bb5bd1feb35cb8a2ae1e (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-08-17T22:41:48Z (GMT) No. of bitstreams: 1 EliezerFSF_DISSERT.pdf: 825442 bytes, checksum: 4e1f858f4401bb5bd1feb35cb8a2ae1e (MD5) / Made available in DSpace on 2017-08-17T22:41:55Z (GMT). No. of bitstreams: 1 EliezerFSF_DISSERT.pdf: 825442 bytes, checksum: 4e1f858f4401bb5bd1feb35cb8a2ae1e (MD5) Previous issue date: 2015-02-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / How do Genus Species Ipomoea station included between as weeds commonly found in cultivated areas, especially Ipomoea asarifolia (salsa) reported as a toxic plant species and causes que neurological disorders. There is little studies on the toxicity quantity make consumer cellular and genetic level these plants nos production animals semi-arid region. It was assessed a toxic capacity, cytotoxic and mutagenic of the aqueous extract of species leaves I. asarifolia (Convolvulaceae) about growth roots in Allium cepa bulbs; and about the frequency of micronucleated erythrocytes in bone marrow cells in vivo rodent (micronucleus test). Also it enrolled a median lethal dose (LD50) and studied the effect of weight in males and females and analyzed the behavior of animals (Hippocratic screening). Aqueous extracts of dried leaves (EFS) and Fresh (EFF) of I. asarifolia not presented toxic effects or cytotoxic in Allium cepa bulbs roots strain. Were observed allelopathic effects nos growth of roots. Aqueous extracts of dried leaves showed sublethal effects 5mg/L concentration and 300 mg/L. And the fresh leaves showed stimulatory effects all as concentrations studied. The aqueous extract of dried leaves and fresh not caused toxic effects and cytotoxic. There is not cytotoxic effect or in mutagenic rodent cells. The LD50 was found 754.26 mg/kg. From: No influence of gender (male and female) on the toxic effect, but at concentrations of 300 mg/kg and 600 mg/kg of weight was lost. The results against knowledge producers qua not like dry leaves not harm the production of animals / As espécies do gênero Ipomoea estão inclusas entre as plantas daninhas comumente encontradas em áreas de cultivo, especialmente Ipomoea asarifolia (salsa) relatada como uma espécie vegetal tóxica e que causa distúrbios neurológicos. Existe pouca quantidade de estudos sobre a toxicidade do consumo a nível celular e genético dessas plantas nos animais de produção da região do Semiárido. Foi avaliada a capacidade tóxica, citotóxica e mutagênica do extrato aquoso de folhas da espécie I. asarifolia (Convolvulaceae) sobre crescimento de raízes em bulbos de Allium cepa; e sobre a frequência de eritrócitos micronucleados em células da medula óssea de roedores in vivo (teste do micronúcleo). Também foi obtida a Dose Letal Mediana (DL50) e foi estudado o efeito do peso em machos e fêmeas e analisado o comportamento dos animais (screening hipocrático). Os extratos aquosos de folhas secas (EFS) e frescas (EFF) de I. asarifolia não apresentaram efeitos tóxicos nem citotóxicos em raízes de bulbos de Allium cepa. Foram observados efeitos alelopáticos nos crescimentos de raízes. Os extratos aquosos de folhas secas apresentaram efeitos subletais nas concentrações de 5mg/L e 300mg/L. E o das folhas frescas apresentaram efeitos estimulatórios em todas as concentrações estudadas. O extrato aquoso de folhas secas e frescas não provocou efeitos tóxicos e citotóxicos. Não houve efeito citotóxico nem mutagênico nas células de roedores. A DL50 encontrada foi 754,26 mg/Kg. Não houve influência do gênero (Macho e fêmea) sobre o efeito tóxico, mas nas concentrações de 300 mg/Kg e 600 mg/Kg houve perda de peso. Os resultados vão de encontro ao conhecimento dos produtores no qual as folhas secas não prejudicam o animal de produção / 2017-08-08
893

Toxicology and molecular epidemiology of microbes detected in surface water in the Western Cape: The Impact of Informal Settlement

Maboza, Ernest J.M. January 2013 (has links)
>Magister Scientiae - MSc / Informal settlements are often implicated in surface water pollution with faecal matter. In most instances faecal pollution in the associated surface waters persists despite improvements in sewage removal infrastructure. This study evaluates the importance of investigating the water quality of the Plankenbrug River before it reaches Khayamnandi settlement by comparing water quality in spring and in winter upstream (Pre-Khayamnandi) and downstream (Post- Khayamnandi) from the settlement. In this study, faecal indicator bacteria (Escherichia coli and total coliforms) were enumerated using Chromocult agar. E. coli was further characterized with analytical profiling index (API) and haemolysis assays. Both Pre- and Post-Khayamnandi were not significantly different from each other for both total coliforms and E. coli in winter. Pre-Khayamnandi had between 105 and 108 cfu/100 ml for total coliforms while Post-Khayamnandi had total coliform colony count between 106 and 107 cfu/100 ml. E. coli also exhibited a similar pattern with slightly higher counts at Post-Khayamnandi with colony counts from 104 to 107 and 105 to 107 cfu/100 ml. Spring microbial count demonstrated a significant difference to winter counts within each test site (p ≤ 0.01) and across the two sites (p ≤ 0.05). Both total coliforms and E. coli were 102 fold higher at Post-Khayamnandi than at Pre-Khayamnandi in spring. The API assay demonstrated significant difference (p ≤ 0.05) between the two test sites. Pre- Khayamnandi predominantly had two different profiles while Post-Khayamnandi had three. These profiles represented five distinct E. coli biotypes. Sorbitol and sucrose tests within the API assay demonstrated significant differences (p ≤ 0.05) between the two test sites. The prevalence of sorbitol fermenters at Pre-Khayamnandi was 100% while at Post-Khayamnandi it was 73%. Pre-Khayamnandi also demonstrated a significantly higher prevalence of sucrose fermenters than Post-Khayamnandi at 100% and 59% respectively. These differences indicated dissimilar sources of faecal contamination around these sites. Differences in the distributions of sorbitol and sucrose fermenting biotypes demonstrate different toxicity potentials across these two test sites. The haemolysis assay demonstrated that 9% of isolates were haemolytic with reference to both known α- and β-haemolyitic streptococci at Post-Khayamnandi. At Pre-Khayamnandi there was a higher percentage of α- and β-haemolyitic species, 29% and 28%, respectively. Post- Khayamnandi and Pre-Khayamnandi were significantly different from each other with reference to both α- and β-haemolysis (p ≤ 0.05). These haemolytic activities also demonstrate different toxicity potentials across the two sites. In conclusion Khayamnandi contributes to an already heavy faecal load in the Plankenbrug River. Thus remedial measures to maintain high surface water quality of Plankenbrug River should be directed upstream from the Khayamnandi settlement as well as within the settlement equally. This study recommends integration of microbial loads with programs such as the National Microbial Monitoring Program of South Africa to drive prioritization process in directing reclaiming of water quality, inter alia.
894

A bioinorganic study of some cobalt(II) Schiff base complexes of variously substituted hydroxybenzaldimines

Shaibu, Rafiu Olarewaju January 2008 (has links)
Syntheses of Schiff bases were carried out by reacting salicylaldyhde, ortho-vanillin, para-vanillin or vanillin with aniline, 1-aminonaphthalene, 4- and 3-aminopyridine, and also with 2- and 3-aminomethylpyridine. The various Schiff bases obtained from the condensation reaction were reacted with CoCl₂.6H₂0, triethylamine stripped CoCl₂.6H₂0 or Co(CH₃COO)₂ to form cobalt(Il) complexes of ratio 2:1. The complexes obtained from cobalt chloride designated as the "A series" are of the general formulae ML₂X₂.nH₂0 , (L = Schiff base, X = chlorine) while those obtained from cobalt acetate or triethylamine stripped cobalt chloride denoted as "B" and C" are of the general formulae ML₂. nH₂0. The few complexes that do not follow the general formulae highlighted above are: IA [M(HL)₃.Cl₂], (L = N-phenylsalicylaldimine), 4A = (MLCl₂), (L = N-phenylvanaldiminato), 7 A and 21 A (ML₂), (L = N-naphthyl-o-vanaldiminato, and N-methy-2-pyridylsalicylaldiminato respectively), 8A = MLCI, (L = N-naphthylvanaldiminato), 12A = M₂L₃Cl₂, (L = N-4-pyridylvanaldiminato), 15A (MLCI), (L = N-3-pyridyl-o-vanaldiminato). The ligands and their complexes were characterized using elemental analyses and cobalt analysis using ICP, FT-IR spectroscopy (mid and far-IR), NIR-UV/vis (diffuse reflectance), UV/vis in an aprotic and a protic solvents, while mass spectrometry, ¹HNMR and ¹³CNMR, was used to further characterized the ligands. The tautomeric nature of the Schiff bases were determined by examining the behaviour of Schiff bases and their complexes in a protic (e.g. MeOH) and non-protic (e.g. DMF) polar solvents. The effects of solvents on the electronic behaviour of the compounds were also examined. Using CDCl₃, the NMR technique was further used to confirm the structures of the Schiff bases. The tentative geometry of the complexes was determined using the spectra information obtained from the far infrared and the diffuse reflectance spectroscopy. With few exceptions, most of the "A" series are tetrahedral or distorted tetrahedral, while the "B + C" are octahedral or pseudooctahedral. A small number of complexes are assigned square-planar geometry owing to the characteristic spectral behaviour shown. In order to determine their biological activity, two biological assay methods (antimicrobial testing and brine shrimp lethality assay) were used. Using disc method, the bacteriostatic and fungicidal activities of the various Schiff bases and their respective complexes to Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa as well as Aspergillus niger, were measured and the average inhibition zones are tabulated and analysed. Both the Schiff bases and their complexes showed varying bacteriostatic and fungicidal activity against the bacteria and fungus tested. The inhibition activity is concentration dependent and potential antibiotic and fungicides are identified. To determine the toxicity of the ligands and their corresponding cobalt(II) complexes, brine shrimp lethality assay was used. The LD₅₀ of the tested compounds were calculated and the results obtained were tabulated for comparison.
895

Degradation of atrazine by homogeneous photocatalysis using Fe(III)/UV/air system and evaluation of potential toxicity of atrazine and its metabolites

KELTNEROVÁ, Lucie January 2016 (has links)
Atrazine photochemical degradation in homogeneous phase using Fe(III)/UV/air system was studied. Two toxicity assessments, a Lemna minor growth inhibition test and a Daphnia magna acute immobilisation test, were employed to test potential toxicity of atrazine and its degradation products. The occurrence of atrazine in rivers from the Vltava River basin was evaluated from the analyses performed by Povodí Vltavy, State Enterprise.
896

Criopreservação de embriões de Astyanax altiparanae influência dos ácidos graxos poli-insaturados na resistência dos embriões ao frio, aos crioprotetores e a vitrificação. /

Bashiyo-Silva, Cristiane January 2018 (has links)
Orientador: Rosicleire Veríssimo Silveira / Resumo: O objetivo deste trabalho a incorporação de ácidos graxos essenciais nas membranas dos embriões de Astyanax altiparanae, visando a determinação de protocolos para a crioconservação de embriões desta espécie de peixe neotropical.Para realização do experimento foram selecionados 2400 espécimes deA. altiparanae. Um grupo foi alimentado com ração comum, denominado de Ração Comercial (RC), e outro alimentado com ração comum acrescida de 5% de óleo de peixe marinho, denominado de Ração Comercial com Óleo de peixe marinho (RC+O). No Capítulo I, foi realizado análise de ácidos graxos no fígado, gônada e embrião. E verificado a mobilização destes ácidos graxos e sua influência. No Capítulo IIverificamos a permeabilização do córion nos embriões quando expostos a solução de pronase-E 25mg/mL, por períodos de 10, 20, 30s. Também foi analisado a sensibilidade dos embriões RC e RC+O aos crioprotetores. Os embriões foram expostos a soluções de propileno glicol, metanol, dimetil sulfóxido, dimetil, formamida, dimetil acetamida e glicerol, por 20 minutos. Verificou-se a taxa de eclosão e viabilidade das larvas após a eclosão. No Capítulo III os embriões do grupo RC e RC+O foram vitrificados em solução de propileno glicol 5M, na fase de seis somitos.No capítulo IV buscou-se o resfriamento dos embriões de RC e RC+O a tempeturas de 15°C, 5°C e 0°C, por um período de 12h. Os embriões foram expostos a soluções sem crioprotetor, com propileno glicol 1M e 2M. / Abstract: The objective of this work was the incorporation of essential fatty acids in the membranes of the embryos of Astyanax altiparanae, aiming the determination of protocols for the cryopreservation of embryos of this neotropical fish species. For the experiment, 2400 specimens of A. altiparanae were selected. One group was fed with common ration, called Commercial Ration (CR), and the other was fed with common ration plus 5% of marine fish oil, called Commercial Ration with Marine Fish Oil (CR + O). In Chapter I, analysis of fatty acids in the liver, gonad and embryo was performed. And we verified the mobilization of these fatty acids and their influence. In Chapter II we verified the permeabilization of the chorion in the embryos when exposed to 25mg / mL pronase-E solution, for periods of 10, 20, 30s. The sensitivity of the CR and CR + O embryos to the cryoprotectants was also analyzed. The embryos were exposed to solutions of propylene glycol, methanol, dimethyl sulfoxide, dimethyl, formamide, dimethyl acetamide and glycerol for 20 minutes. The hatch rate and viability of the larvae after hatching were checked. In Chapter III the embryos of the CR and CR + O group were vitrified in 5M propylene glycol solution in the six somites phase. In Chapter IV, the cooling of the CR and CR + O embryos was sought at temperatures of 15 ° C, 5 ° C and 0 ° C for a period of 12 hours. The embryos were exposed to cryoprotectant solutions with 1M and 2M propylene glycol. / Doutor
897

Etude de l'intéraction nanoparticules-bactéries : application à l'élaboration d'un biocapteur / Study of the interactions between nanoparticles and bacteria : application in the design of a biosensor for bacteria detection

Mathelié-Guinlet, Marion 17 October 2017 (has links)
Malgré l'enthousiasme croissant pour les nanotechnologies, les nanoparticules (NPs) peuvent interagir avec les systèmes biologiques et affecter leur comportement, et pourraient ainsi présenter un danger pour les écosystèmes et l’Homme. Il est donc essentiel de connaître leurs mécanismes d'interactions afin non seulement de prévenir leurs risques potentiels, mais également de bénéficier de leurs propriétés uniques, par exemple dans la conception des biocapteurs. Dans ce contexte, nous étudions la cytotoxicité des NPs de silice, de tailles et charges diverses, sur les propriétés des bactéries Escherichia coli et Bacillus subtilis, au moyen de la microscopie à force atomique et des tests de viabilité. Les NPs chargées négativement (NPs-) de diamètre inférieur à un diamètre critique φc, 50 - 80 nm, (i) mènent à l'isolation des bactéries E. coli, (ii) induisent une "sphérification" de la cellule initialement en bâtonnet, (iii) provoquent des lésions dans la membrane externe et une réorganisation de sa structure. Pour la bactérie B. subtilis, seule la dégradation de la structure du peptidoglycane a été observée. Cependant, pour les deux souches, une activité antibactérienne a été démontrée pour les NPs- en dessous de φc, qui peuvent conduire à la lyse cellulaire tandis que, au-dessus de φc, les NPs- n’ont aucun effet sur la population, la morphologie ou la structure bactérienne. En ce qui concerne les NPs chargées positivement, elles conduisent, quel que soit leur diamètre, à une forte agrégation des cellules, en raison des interactions électrostatiques, et tendent à favoriser la formation d'invaginations membranaires, ne menant pas nécessairement à la lyse cellulaire. Cette étude fondamentale a mené au développement d’un biocapteur électrochimique pour la détection de bactéries, application notable pour des problèmes biomédicaux, environnementaux et de défense. Les NPs, intégrées à ces outils, offrent un mode de détection rapide, très sensible et peu coûteux. Expérimentalement, une multicouche de polyélectrolytes a été utilisée pour immobiliser des NPs inoffensives (φ = 100 nm), auxquelles sont ensuite fixés des anticorps spécifiques, afin d'améliorer la détection finale de la bactérie E. coli. L’ensemble des étapes a été optimisé par le procédé du spin coating et étudié à l'aide de mesures de microbalance à quartz et de voltametrie cyclique. L’intégration de NPs au biocapteur a permis une détection linéaire et non saturée des bactéries E. coli dans une large gamme de concentration (jusqu’à 10^9 CFU/mL) pour une limite de détection de 10^6 CFU/mL. / Despite the growing enthusiasm for nanotechnologies, nanoparticles (NPs) might put environmental safety and human health at risk, as they can interact with biological systems and affect their behavior. It is therefore essential to know their mechanisms of interactions in order not only to prevent their potential risks but also to benefit from their unique properties, such as in biosensors design. In this context, we study the cytotoxicity of silica NPs, with diverse sizes and charges, on the properties of Escherichia coli and Bacillus subtilis bacteria, by means of atomic force microscopy and viability tests. Negatively charged NPs (NPs-) with a diameter φ lower than a critical diameter φc, 50 - 80 nm, (i) lead to the isolation of E. coli bacteria, (ii) induce a "spherification" of the cell initially rod shaped, and (iii) cause the formation of pore-like lesions in the outer membrane and a reorganization of its structure. For B. subtilis bacteria, only the degradation of the peptidoglycane’s structure was observed. Though, for both strains, an antibacterial activity was shown for NPs- below φc, which potentially lead to the cell lysis whereas, above φc, NPs- have no effect on population, morphology or bacterial structure. As positively charged NPs are concerned, whatever their diameter, they lead to a strong aggregation of the cells, due to electrostatic interactions, and tend to favor the formation of membrane invaginations, not necessarily involving cell lysis. This fundamental study has been used to develop an electrochemical biosensor for bacteria, which are of great importance for biomedical, environmental and defense issues. NPs involved in such tools offer a fast, high-sensitive and low-cost way of detection. A polyelectrolyte multilayer was used to immobilize harmless NPs (φ = 100 nm), which are, then, functionalized with specific antibodies, in order to enhance the final detection of E. coli bacteria. All steps were optimized by a spin coating process and studied through quartz microbalance and cyclic voltametry measurements. Integrating NPs in this biosensor resulted in a linear and unsaturated detection of E. coli bacteria in a wide range of concentration (until 10^9 CFU/mL) and a limit of detection of 10^6 CFU/mL.
898

Avaliação pré-clínica da farmacocinética e da toxicidade aguda em roedores do candidato a fármaco antitumoral LaSOM 65 / Pre-clinical evaluation of the pharmacokinetics and acute toxicity in rodents of the anticancer candidate LaSOM 65

Torres, Bruna Gaelzer Silva January 2012 (has links)
Objetivo: Contribuir para o desenvolvimento do candidato a antitumoral (LaSOM 65) através da avaliação farmacocinética pré-clínica em roedores de diferentes doses pelas vias i.v., p.o e i.p. e avaliação da toxicidade aguda do composto. Metodologia: LaSOM 65 foi administrado a ratos Wistar nas doses de 1 mg/kg i.v. bolus (n = 8), 10 e 30 mg/kg p.o. e 30 e 90 mg/kg i.p. (n = 6/grupo). As concentrações plasmáticas foram quantificadas por CL-UV em método desenvolvido e validado. A ligação às proteínas foi determinada por ultrafiltração e a distribuição tecidual foi avaliada por homogeneizado de tecido após administração i.v. de 1 mg/kg (n = 3 animais/ponto de coleta). Para o ensaio de toxicidade aguda, dose única de 1, 2,5 e 5 mg/kg i.v. e 50, 100 e 150 mg/kg p.o. de LaSOM 65 foi administrada aos animais. Ganho de peso, massa relativa dos tecidos, determinação de parâmetros bioquímicos e hematológicos e uma observação clínica detalhada foram realizados para a avaliação de possíveis efeitos tóxicos. Resultados e Discussão: LaSOM 65 apresentou farmacocinética linear na faixa de dose de 1 a 30 mg/kg (i.v., p.o. e i.p.). Após dose i.v. apresentou um CL = 0,85 ± 0,18 L/h/kg, t1/2 = 1,8 ± 0,7 h e Vd = 1,76 ± 0,24 L/kg. Para a dose de 90 mg/kg i.p. um aumento no Vd (3,2 ± 0,8L/Kg) e t1/2 (2,9 ± 0,9 h) foi observado. O composto apresentou boa biodisponibilidade para as administrações extravasculares (58 e 50% p.o. e 73 e 61% i.p.). A ligação às proteínas foi de 84,7 ± 1,6%. O composto distribuiu-se nos tecidos investigados tendo no pulmão a maior taxa de penetração (ASCtecido/plasma = 2,7) e o cérebro a menor (ASCtecido/plasma = 0,4). Piloereção, diarréia, letargia e dispneia foram os sinais clínicos observados imediatamente após administrações i.v., os quais regrediram após 3 h. Para a via oral nenhuma alteração foi observada. Nenhum outro parâmetro avaliado demonstrou efeitos tociológicos para o LaSOM 65. Conclusões: LaSOM 65 demonstrou uma rápida distribuição tecidual e uma rápida eliminação após administração i.v. Sua boa biodisponibilidade e uma possível ausência de toxicidade apresentada por esta via permitem seu uso oral. A baixa penetração cerebral sugere que desenvolvimento no âmbito farmacotécnico será necessário visando seu uso para o tratamento de gliomas. / Purpose: To contribute with the development of a new anticancer candidate (LaSOM 65) by investigating its pre-clinical pharmacokinetics in rodents after administration of different doses by three routes (i.v., p.o. and i.p.) and acute toxicological evaluation of the compound. Methodology: LaSOM 65 was administrated to Wistar rats in the 1 mg/kg i.v. bolus (n = 8), 10 and 30 mg/kg p.o. and 30 and 90 mg/kg i.p. dose (n = 6/group). Plasma concentrations were determined by a development and validated LC-UV method. Protein binding was determined by ultrafiltration and tissue penetration was investigated in tissue homogenates after i.v. administration of 1 mg/kg (n = 3 animals/time point). For the acute toxicological assay, single administration of LaSOM 65 at the doses of 1, 2.5 and 5 mg/kg i.v. and 50, 100 and 150 mg/kg p.o. were given to the rats. Weight gain, organ relative mass, biochemical and hematological parameters and a detailed clinical observation were evaluated to determine LaSOM 65 toxicity. Results and Discussion: LaSOM 65 showed linear pharmacokinetic between 1 and 30 mg/kg (i.v., p.o and i.p.) with CL = 0.85 ± 0.18 L/h/kg, t1/2 = 1,8 ± 0,7 h and Vd = 1.76 ± 0.24 L/kg after i.v. dosing. After 90 mg/kg i.p. dosing an increase in Vd (3.2 ± 0.8 L/kg) and t1/2 (2.9 ± 0.9 h) were observed. The compound showed good bioavailability after p.o. (58 and 50%) and i.p. (73 and 61%) dosing. The protein biding was 84.7 ± 1.6%. LaSOM 65 distributed into the tissues investigated with a higher penetration ratio into lung (AUCtissue/plasma = 2.7) than into brain (AUCtissue/plasma = 0.4). Piloerection, diarrhea, lethargy and dyspnea were the clinical signs observed immediately after the i.v. administrations and they regressed 3 h post-dosing. No alterations were observed after p.o. dosing. Conclusions: LaSOM 65 showed a rapid tissue distribution and elimination after i.v. administration. Its good bioavailability together with the probably absence of toxicity for the oral route allowed its use by this route. The low brain penetration suggests that a pharmaceutical development will be necessary if LaSOM 65 is intended for the treatment of glioma.
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Estudo dos efeitos dos extratos das folhas da Bauhinia microstachya : análise in vitro, potencial antioxidante e hipoglicemiante em ratos diabéticos induzidos por aloxano

Silva, Evandro Gomes da January 2007 (has links)
Diabetes mellitus (DM) é um grupo de anomalias metabólicas caracterizadas principalmente pela hiperglicemia. Componentes macro- e microvasculares, além de neuropáticos inter-relacionados com a elevação da glicemia são fatores freqüentemente envolvidos em acidentes cérebro-vasculares, infartos miocárdicos, doença vascular periférica, retinopatia e nefropatia diabética. Na literatura científica atual pode-se obter um grande número de trabalhos onde o uso de plantas medicinais, extratos ou substâncias vegetais isoladas é positivamente relacionado ao tratamento do DM e/ou seus efeitos diretos e indiretos. Bauhinia microstachya (RADDI) MACBR. (Caesalpinaceae) é uma planta que ocorre naturalmente na região sul do Brasil onde é conhecida popularmente como “escada-de-macaco”. Algumas populações fazem uso de preparações das folhas no tratamento do DM e suas complicações. Neste trabalho propomos que os extratos aquoso e hidro-etanólico, obtidos das folhas de B. microstachya possuem ação antioxidante in vitro e que o extrato hidro-etanólico apresenta poder antioxidante in vivo, além de efeito hipoglicemiante, apesar de ser potencialmente hepatotóxico. / Diabetes mellitus (DM) is a heterogeneous group of metabolic disorders characterized by chronic hyperglycemia. Both DM types share aspects that are related to uncontrolled hyperglycaemia: alterations in the carbohydrate, fat, and protein metabolism. In addition, increased cardiovascular disease risk, retinopathy, nephropathy, and neuropathy are vascular complications associated to diabetes. In scientific literature there are several reports where the use of folk medicine is positively related to DM treatment and/or their direct and indirect effects. Bauhinia microstachya (RADDI) MACBR. (Caesalpinaceae) is a creeper plant that occurs naturally in southern Brazil where is popularly known as “escada-de-macaco” (monkey’s ladder) and often used as herbal antidiabetic medicine. In the present work, we propose that the extracts obtained from B. microstachya leaves have in vitro and in vivo antioxidant action, hypoglycemic effect, despite their hepatotoxic potential.
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Avaliação da toxicidade oral aguda e em doses repetidas do xarope contendo os extratos de Roripa nasturtium Rusby (Agrião) , Musa spp. (Bananeira), Ficus carica Linné (Figueira), Tagetes minuta Linné (Chinchilia) e mel de abelhas em ratos e ratas Wistar

Jacobus, Daniela January 2006 (has links)
O fitoterápico Xarope de Agrião Composto Cibecol® é uma associação de extratos de Roripa nasturtium Rusby (Agrião), Musa spp. (Bananeira), Ficus carica Linné (Figueira), Tagetes minuta Linné (Chinchilia) e mel de abelhas. Avaliou-se a segurança deste fitoterápico através de estudos de toxicidade aguda e subcrônica, tendo como base a resolução Nº 90, de 16 de março de 2004 da ANVISA. Para o teste de toxicidade aguda, ratos Wistar de ambos os sexos foram tratados por via oral com uma única dose de 26 ml/kg, correspondendo a 20 vezes a dose terapêutica indicada pelo fabricante para seres humanos adultos. Os resultados revelaram não haver sinais de toxicidade sistêmica, não causando interferência no desenvolvimento ponderal dos animais, nos consumos de água e ração, nas produções de urina e fezes, bem como alterações macroscópicas nos órgãos dos animais. Avaliou-se também a exposição a doses repetidas do fitoterápico. Constituíram-se em quatro grupos experimentais (10 animais/sexo/dose), onde administrou-se por via oral a ratos Wistar, durante 30 dias, doses diárias de 1,3 ml/kg, 6,5 ml/kg e 13 ml/kg, respectivamente a dose terapêutica indicada pelo fabricante para seres humanos adultos, 5 vezes, e 10 vezes a dose terapêutica, além de um grupo controle, onde foi administrado o veículo do fitoterápico. Os resultados revelaram ausência de toxicidade sistêmica, fundamentados na ausência de alterações hematológicas e bioquímicas sangüíneas, bem como no peso e análises histopatológicas dos órgãos, nos diferentes grupos. Concluiu-se que, a utilização do fitoterápico nas doses e períodos referidos, pode ser considerada segura. / The phytotherapic Xarope de Agrião Composto Cibecol® is an association of extracts of Roripa nasturtium Rusby (water-cress), Musa spp. (banana tree), Ficus carica Linné (fig tree), Tagetes minuta Linné (Chinchilia) and honey. The safety of the phytotherapic was evaluated through studies of acute and sub-chronic toxicity, being based in the resolution Nº 90, March 16th, 2004 from ANVISA. For the test of acute toxicity Wistar rats of both sexes were treated orally with a single dose of 26 ml/kg, which corresponds to 20 times the therapeutic dose indicated by the producer for adult humans. The results revealed that there are no signals of systemic toxicity, no interference in the development of weight gain in the animals, in water and feed consume, in the production of urine and feces, neither macroscopic alterations in the animals’ organs. It was also evaluated the exposition of repeated doses of the phytotherapic (sub-chronic toxicity). Four experimental groups (10 animals/sex/dose) were orally treated during 30 days with daily doses of 1.3 ml/kg, 6.5 ml/kg and 13 ml/kg, respectively the therapeutic dose indicated to humans, 5 times, and 10 times the therapeutic dose, and a control group, receiving the phytotherapic vehicle. The results revealed the absence of systemic toxicity, based in the absence of hematological and blood biochemical alterations, as well as weigh and histopatological analysis of organs, in the different groups. It was concluded that the utilization of the referred phytotherapic in the mentioned doses and periods might be considered secure.

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