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Item Avaliação da atividade mutagênica e antimutagênica da Annona crassiflora Mart. (Araticum) pelo teste do micronúcleo em camundongos Mus musculus(Universidade Federal de Goiás, 2001-08-23) FERREIRA, Francinez Linhares; CHEN, Lee Chen; http://lattes.cnpq.br/4621907105842007RESUMO CAPÍTULO I The araticum (Annona crassiflora Mart.) is a typical brazilian plant found in cerrados of Brazil. This plant contains acetogenins that presents cytotoxic, antitumorigenic, antiparasitic and antimicrobial properties. Its leaves, barks, fruits and seeds are used by the population as therapeutic medicine to treat several diseases as diarrhoea, rheumatism and syphilis. In the present study we have evaluated the mutagenic activity of the crude ethanolic extract of leaves of araticum though quantification of micronuclei induced in mice bone marrow. Doses of 10 mg/kg (5% of LD50), 20 mg/kg (10% of LD50), 50 mg/kg (25% of LD50), 100 mg/kg (50% of LD50) and 160 mg/kg (80% of LD50) were applied i.p. in mice Mus musculus, in groups of 5 (five) animals for each dose. The cytological preparations were made according to Heddle`s methodology. For all the applied doses, frequency of micronucleated polychromatic erythrocytes (MNPCE) was evaluated after 24, 48 and 72 h of treatment. The cytotoxicity was evaluated by ratio the between numbers of polychromatic and normochromatic erythrocytes (PCE/NCE). Ours results indicated an absence of significantly increased of micronuclei for all the doses tested (p>0,01). Thus, we concluded that the phytoterapic araticum did not present mutagenic activity under our experimental conditions. However, the toxic activity was observed upon analysis of LD50 and PCE/NCE ratio. RESUMO CAPÍTULO II Annona crassiflora Mart. (araticum) is a typical brazilian plant found in cerrados of Brazil. This plant contains acetogenins that presents cytotoxic, antitumorigenic, antiparasitc and antimicrobial properties. Its leaves, barks, fruits and seeds are used by the population as therapeutic medicine to treat several diseases as diarrhoea, rheumatism and syphilis. In the present study we have evaluated the antimutagenic activity of the crude ethanolic extract of leaves of araticum through quantification of micronuclei induced in mice bone marrow. Doses of the extract (10mg/kg, 20mg/kg, 50mg/kg, 100mg/kg and 160 mg/kg) and MMC (4mg/kg) were co-applied i.p in mice Mus musculus in groups of 5 (five) animals for each dose. The cytological preparations were made in according to Heddle s methodology. For all the applied doses, frequency of micronucleated polychomatic erythrocytes (MNPCE) was evaluated after 36 h of treatment. The obtained results indicated that the crude ethanol extract from leaves ay doses of 20 mg/kg, 50 mg/kg and 100 mg/kg inhibited significantly reduced frequencies of micronuclei (P<0.01). Thus, we concluded that the phytoterapic araticum exerted an antimutagenic effect.Item Anotação e caracterização preliminar de genes de celulose sintase em diferentes espécies de Eucalyptus(Universidade Federal de Goiás, 2006-12-01) SALAZAR, Marcela Mendes; COELHO, Alexandre Siqueira Guedes; http://lattes.cnpq.br/0840926305216925Cellulose is the world s most abundant polymer, being the main constituent of plant biomass. Genes from CesA family, that encodes the cellulose synthase enzyme, was identified in several plant species, especially in Arabidopsis thaliana, in which three of them (AtCesA4, AtCesA7 e AtCesA8) were associated with secondary cell wall cellulose production. Eucalyptus species represent an important target of genetic improvement studies, since it is the most planted forest genus in the world, beyond deserving a special place in the international market of cellulose and paper. The molecular breeding technology enables that gene characterization can be applied to forest species genetic improvement programs with the aim to improve the quality and productivity of its products. In this work, 320 Eucalyptus ESTs, separated in four genes related with cellulose production in secondary cell wall, using AtCesA4, AtCesA7 e AtCesA8 genes as reference. For these genes, primers were designed in order to screen an Eucalyptus BACs library. An emphasis was given to genes that are orthologs to AtCesA7 from Arabidopsis thaliana for witch it was sequenced a 1197 base pairs region from the BACs library and this served as a support to expression level studies of this genes in different species/tissues, showing that this is preferentially expressed in xylem and weakly expressed in leaves. The expression level of this gene was higher in E. urophylla than in other species studied. Sequences from approximately 500bp was obtained from different Eucalyptus species and in these, with one intron between two exons, the amount of SNPs in the intron (4), as waited, was higher than that found in exons (1 in each), although the intron nucleotide diversity index (π) (0,0824) were less than in the exon (0,2029). In this manner, one expects that this work can contribute for one better understanding of the mechanisms involved in biosynthesis and regulation of the cellulose pathway in Eucalyptus species, as well as subsidize genetic mapping studies and linkage disequilibrium analysis for this genus.Item AVALIAÇÃO DAS ATIVIDADES GENOTÓXICA E ANTIGENOTÓXICA DE DUGUETIA FURFURACEA EM BACTÉRIAS E CAMUNDONGOS(Universidade Federal de Goiás, 2008-02-25) SILVA, Carolina Ribeiro e; CHEN, Lee Chen; http://lattes.cnpq.br/4621907105842007The plant Duguetia furfuracea (St. Hil.) Benth and Hook. f. (1862), belongs to the family Annonaceae, is popularly known as sofre‐do‐rim‐quem‐quer, araticum‐do‐cerrado and ata‐do‐mato. This plant occurres in several Brazilian states, as Amazonas, Bahia, Distrito Federal, Goiás, Minas Gerais, Mato Grosso, Mato Grosso do Sul and São Paulo. It is commonly used by people as anti‐rheumatic and to cure renal colic. Previous studies have described therapeutic activity of this plant with trypanocidal, antiplasmodial and antiprotozoal effects. Due to the large utilization of this plant by the local people, the present work aimed to evaluate the genotoxic/mutagenic, antigenotoxic/antimutagenic and cytotoxic activities of lyophilized leaf extract of D. furfuracea by the lisogenic induction test (Inductest) and the mice bone marrow micronucleus assay (Micronucleus Test). The lisogenic induction test was performed according Moreau et al., (1976) using E. coli WP2s(λ) and RJF013 strains. To evaluate the genotoxic and toxic activities, the doses employed were 1 mg, 2 mg, 5 mg e 10 mg, while to evaluate the antigenotoxic action the doses were of 0,5 mg, 1 mg, 2 mg, 5 mg e 10 mg co‐treated with 0,5 μg de mitomycin C. Micronucleus test in the bone marrow of mice was performed according to Schmid (1975). To evaluate mutagenic activity, mice were treated with three different doses of plant extract (100, 200 and 300 mg/Kg body weight), to evaluate antimutagenic activity, mice were treated with the same doses co‐administered with 4 mg/kg of mitomycin C. The genotoxic action was evaluated by the frequency of micronucleated polychromatic erythrocytes (MNPCE) and cytotoxicity was evaluated by the polychromatic and normochromatic erythrocytes ratio (PCE/NCE). The results obtained from the evaluation of mutagenicity of this plant showed that the extract of D. Furfuracea didn t increase significantly (p>0.05) the frequency of MNPCE compared to negative control. Cytotoxicity was evident in all applied doses (p<0.05). Concerning antimutagenicity, all doses of extract reduced significantly the frequency of MNPCE compared to the positive control group (p<0.05). In both tests, the results obtained demonstrated that the extract of D. furfuracea presented cytotoxicity; however, it didn t show genotoxic or mutagenic effects in bacteria and mice bone marrow respectively. In the other hand, it was observed a antigenotoxic and antimutagenic action.