RESUMO
Invasive aspergillosis is a disease responsible for high mortality rates, caused mainly by Aspergillus fumigatus. The available drugs are limited and this disease continues to occur at an unacceptable frequency. Gene disruption is essential in the search for new drug targets. An efficient protocol for A. fumigatus gene disruption was described but it requires ethidium bromide, a genotoxic agent, for DNA staining. Therefore, the present study tested SYBR safeTM, a non-genotoxic DNA stain, in A. fumigatus gene disruption protocol. The chosen gene was cipC, which has already been disrupted successfully in our laboratory. A deletion cassette was constructed in Saccharomyces cerevisiae and used in A. fumigatus transformation. There was no statistical difference between the tested DNA stains. The success rate of S. cerevisiae transformation was 63.3% for ethidium bromide and 70% for SYBR safeTM. For A. fumigatus gene disruption, the success rate for ethidium bromide was 100 and 97% for SYBR safeTM. In conclusion, SYBR safeTM efficiently replaced ethidium bromide, making this dye a safe and efficient alternative for DNA staining in A. fumigatus gene disruption.
Assuntos
Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Dano ao DNA/efeitos dos fármacos , Etídio/toxicidade , Corantes Fluorescentes/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genéticaRESUMO
This study was undertaken primarily to develop new simple sequence repeat (SSR) markers for Capsicum. As part of this project aimed at broadening the use of molecular tools in Capsicum breeding, two genomic libraries enriched for AG/TC repeat sequences were constructed for Capsicum annuum. A total of 475 DNA clones were sequenced from both libraries and 144 SSR markers were tested on cultivated and wild species of Capsicum. Forty-five SSR markers were randomly selected to genotype a panel of 48 accessions of the Capsicum germplasm bank. The number of alleles per locus ranged from 2 to 11, with an average of 6 alleles. The polymorphism information content was on average 0.60, ranging from 0.20 to 0.83. The cross-species transferability to seven cultivated and wild Capsicum species was tested with a set of 91 SSR markers. We found that a high proportion of the loci produced amplicons in all species tested. C. frutescens had the highest number of transferable markers, whereas the wild species had the lowest. Our results indicate that the new markers can be readily used in genetic analyses of Capsicum.
Assuntos
Capsicum/genética , Repetições de Microssatélites/genética , Alelos , Loci Gênicos , Marcadores Genéticos , Motivos de Nucleotídeos/genética , Polimorfismo Genético , Especificidade da EspécieRESUMO
O objetivo do presente estudo foi comparar o comportamento de comparação social (CCS) de jovensadultos, segundo a insatisfação corporal (IC) e o comportamento alimentar inadequado (CAI).Participaram 563 sujeitos (276 mulheres) entre 1 8 e 35 anos de idade. Teste U de Mann-Whitney foiutilizado para comparar os CCS segundo a IC e o CAI. Foi identificada diferença para oscomportamentos de comparação social entre o grupo de sujeitos satisfeitos e insatisfeitos, e também paraos grupos com e sem comportamentos alimentares inadequados, do sexo feminino. Conclui-se que ocomportamento de comparação social está associado à insatisfação corporal e aos comportamentosalimentares inadequados de mulheres, o mesmo não ocorrendo para os homens(AU)
Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Imagem Corporal/psicologia , Comportamento Alimentar/psicologiaRESUMO
Lipid-lowering therapy has shown a high degree of variability in clinical response and there is evidence that the variability in drug response between individuals is due to genetic factors. Thirteen single nucleotide polymorphisms (SNPs) within the ESR1 gene were evaluated with basal lipid and lipoprotein levels, as well as response to lipid-lowering therapy, in 495 hypercholesterolemic individuals of European descent receiving simvastatin or atorvastatin. Significant associations were detected between rs4870061 (P=0.040, corrected P-value (PC)=0.440), rs1801132 (P=0.002, PC=0.022) and the SNP rs3020314 (P=0.013, PC=0.143) with triglyceride (TG) baseline levels. The rs4870061 was also associated with high-density lipoprotein cholesterol (HDL-C) baseline levels (P=0.045, PC=0.495). Regarding statin efficacy, rs2234693 C/C was associated with greater HDL-C increase (P=0.037; PC=0.407) and rs3798577 T allele was associated with greater total cholesterol (TC) reduction (P=0.019; PC=0.209) and greater TG reduction (P=0.026; PC=0.286). These associations suggest that ESR1 polymorphisms are in part responsible for the TC, HDL-C and TG variation levels and this effect may be sex-specific.
Assuntos
Atorvastatina/uso terapêutico , Receptor alfa de Estrogênio/genética , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Lipídeos/sangue , Variantes Farmacogenômicos , Polimorfismo de Nucleotídeo Único , Sinvastatina/uso terapêutico , Idoso , Biomarcadores/sangue , Brasil , Feminino , Frequência do Gene , Haplótipos , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/genética , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Farmacogenética , Fenótipo , Estudos Prospectivos , Fatores Sexuais , Resultado do TratamentoRESUMO
INTRODUCTION: This study aimed to verify the association between the JAK2 46/1 haplotype (V617F positive) and some hematological parameters in BCR-ABL-negative chronic myeloproliferative neoplasms (cMPNs) in our population. METHODS: The blood samples obtained from the patients with cMPN were genotyped for the JAK2 V617F mutation and JAK2 rs10974944 SNP screening using a PCR-RFLP assay. RESULTS: The JAK2 V617F mutation was detected in 80.15% of patients. The G variant of rs10974944 was more frequent in all MPNs, especially those that were JAK2 V617F positive, than in the control population. We also compared the 46/1 haplotype status in each MPN disease entity, polycythemia vera (PV), essential thrombocythemia (ET), primary myelofibrosis (PMF), and MPNu with controls. The G allele frequency relative to controls was significantly enriched in patients with PV and ET, but not in those with PMF and MPNu. PV and ET patients especially, all of whom had the JAK2 V617F mutation, showed significant excess of the G allele. The frequency of JAK2 V617F mutation was associated with elevated hematological parameters, but when we analyze the occurrence of the mutation and the presence of the G allele, just the high hemoglobin was significantly. CONCLUSION: In agreement with previous reports, JAK2 46/1 haplotype for JAK2 V617F was associated with cMPN positive in Brazilian patients.
Assuntos
Haplótipos , Janus Quinase 2/genética , Mutação , Transtornos Mieloproliferativos/genética , Polimorfismo de Nucleotídeo Único , Alelos , Brasil/epidemiologia , Feminino , Frequência do Gene , Humanos , Masculino , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/epidemiologia , Razão de Chances , FenótipoRESUMO
This study compared the different factors associated with eating behaviors among young female and male athletes and non-athletes. A total of 580 female and male athletes and 362 female and male non-athletes between 10 and 19 years old participated. We used the subscales of the Eating Attitudes Test (EAT-26) to evaluate the factors associated with unhealthy eating behaviors. We found higher scores for females on the diet subscale compared with males, regardless of athletic group (P < 0.05). Non-athlete youths scored higher on this subscale compared with male athletes (P < 0.05). Our findings indicate higher scores for female athletes with regard to the bulimia and preoccupation with food subscale compared with other the groups (P < 0.05). Moreover, we observed that non-athlete males were more likely to engage in binge eating compared with athletes of the same sex (P < 0.05). Finally, females had higher scores on the oral self subscale than males, regardless of athletic group (P < 0.05). We concluded that the factors associated with eating behaviors differ with regard to sex and group.
Assuntos
Atletas/estatística & dados numéricos , Bulimia/epidemiologia , Restrição Calórica/estatística & dados numéricos , Comportamento Alimentar/fisiologia , Adolescente , Atletas/psicologia , Atitude Frente a Saúde , Imagem Corporal/psicologia , Brasil/epidemiologia , Bulimia/psicologia , Restrição Calórica/psicologia , Estudos de Casos e Controles , Criança , Estudos Transversais , Comportamento Alimentar/psicologia , Feminino , Humanos , Masculino , Fatores Sexuais , Inquéritos e Questionários , Adulto JovemRESUMO
Se evaluo la sensibilidad in vitro al benznidazol y al extracto de hojas de la planta Zanthoxylum chiloperone de diez cepas del Trypanosoma cruzi. Se utilizaron formas epimastigotas de las cepas, pertenecientes a diferentes linajes, diferente procedencia geografica, incluidas tres de Paraguay, y aisladas de hospederos distintos, abarcando humanos, triatominos y animales silvestres. El grado de sensibilidad a la droga y al extracto vegetal fue estimado por el porcentaje de lisis de los parasitos a las 24 y 48 horas de exposicion. Se observo un amplio rango de variacion en el porcentaje de lisis entre las cepas, de 22,2% a 90,8% a la concentracion del benznidazol de 200 ug/mL, con el hallazgo de una cepa con sensibilidad nula al mismo. Con respecto al extracto vegetal, tres concentraciones fueron testadas, de 500, 700 y 900 ug/mL, observandose variaciones en los porcentajes de lisis entre las cepas con las dos primeras concentraciones, entre un 2,1% y 100%, con lisis total en todas las cepas a la concentracion de 900 ug/mL. No se observo asociacion entre la diversidad de respuesta a los compuestos y la clasificacion de las cepas ni con su origen geografico y tipo de hospedero. Estas diferencias observadas resaltan la heterogeneidad de las poblaciones naturales del T. cruzi, aspecto importante a tener en cuenta en los estudios de sensibilidad a quimioterapeuticos y en los tamizajes primarios de nuevos antichagasicos. Asi mismo, se destaca la eficacia del extracto vegetal sobre diferentes cepas de este parasito.
Assuntos
Testes de Sensibilidade Microbiana , Trypanosoma cruziRESUMO
This study determined the species of microhymenopterous of Diptera present in cattle and buffalo dung, from May 2003 to June 2004 and from April 2006 to March 2007 in chicken manure. All samples were collected in Southern Goiás State, Brazil. The dipterous pupae were obtained by the flotation method. They were individually placed in gelatin capsules until the emergence of the flies and/or their parasitoids. The percentages of parasitism in cattle dung and chicken manure were 12.4% and 10.0%, respectively.
Assuntos
Animais , Masculino , Feminino , Bovinos , Controle Biológico de Vetores/métodos , Dípteros/parasitologia , Búfalos , Galinhas , FezesRESUMO
This study determined the species of microhymenopterous of Diptera present in cattle and buffalo dung, from May 2003 to June 2004 and from April 2006 to March 2007 in chicken manure. All samples were collected in Southern Goiás State, Brazil. The dipterous pupae were obtained by the flotation method. They were individually placed in gelatin capsules until the emergence of the flies and/or their parasitoids. The percentages of parasitism in cattle dung and chicken manure were 12.4% and 10.0%, respectively.(AU)
Assuntos
Animais , Masculino , Feminino , Bovinos , Dípteros/parasitologia , Controle Biológico de Vetores/métodos , Fezes , Búfalos , GalinhasRESUMO
This study determined the species of parasitoids of Diptera present in forest, rural, and urban areas in the municipality of Monte Alegre, MG, from March to November 2006. The percentages of parasitism in forest, rural, and urban areas were 14.3 percent, 11.0 percent, and 18.8 percent, respectively. The most frequent species (34.7 percent) was Triplasta atrocoxalis (Ashmead) (Hymenoptera: Figitidae).
Assuntos
Animais , Contagem de Ovos de Parasitas/métodos , Controle Biológico de Vetores/métodos , Fezes/parasitologia , Himenópteros/parasitologia , Zoneamento/classificaçãoRESUMO
This study determined the species of parasitoids of Diptera present in forest, rural, and urban areas in the municipality of Monte Alegre, MG, from March to November 2006. The percentages of parasitism in forest, rural, and urban areas were 14.3 percent, 11.0 percent, and 18.8 percent, respectively. The most frequent species (34.7 percent) was Triplasta atrocoxalis (Ashmead) (Hymenoptera: Figitidae).(AU)
Assuntos
Animais , Contagem de Ovos de Parasitas/métodos , Himenópteros/parasitologia , Fezes/parasitologia , Controle Biológico de Vetores/métodos , Zoneamento/classificaçãoRESUMO
We investigated the effect of single-nucleotide polymorphisms in sterol regulatory element-binding factors-1a and -2 (SREBF-1a and SREBF-2) and SREBF cleavage-activating protein (SCAP) genes on lipid-lowering response to simvastatin. In all, 146 hypercholesterolemic patients of European descent were prospectively treated with simvastatin 20 mg/day for over 6 months. Of these 99 subjects completed the 6-month follow-up. Plasma lipids and lipoproteins were measured before and throughout the study. The mean percentage decrease in plasma total cholesterol (TC) was greater in subject carriers of SCAP 2386G allele compared with those homozygous for 2386A allele (-29.6+/-13.4 vs -22.1+/-13.8%, P=0.007). About 61% of the 2386G carriers were above-average responders for TC levels (DeltaTC -27.8%), whereas only 29% of 2386A homozygous reached this reduction (P=0.009). Our data suggest that the SCAP 2386A>G gene polymorphism was a significant predictor of TC and triglyceride responses to simvastatin treatment.
Assuntos
Hipercolesterolemia/tratamento farmacológico , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único , Sinvastatina/uso terapêutico , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticolesterolemiantes/uso terapêutico , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Triglicerídeos/sangue , População BrancaRESUMO
The continuous use of triazoles can result in the development of drug resistance. Azole-resistant clinical isolates, spontaneous and induced mutants of Aspergillus fumigatus have been documented. The azoles block the ergosterol biosynthesis pathway by inhibiting the enzyme 14-alpha-demethylase, product of the CYP51. Fungal azole resistance involves both amino acid changes in the target site that alter drug-target interactions and those that decrease net azole accumulation. The reduced intracellular accumulation has also been correlated with overexpression of multidrug resistance (MDR) efflux transporter genes of the ATP-binding cassette (ABC) and the major facilitator superfamily (MFS) classes. About 20 genes are involved in the A. fumigatus ergosterol biosynthesis pathway. There are several duplicated genes in this pathway. Interestingly, erg3 and erg11 showed two copies in A. fumigatus. In general, Aspergillus spp. have proportionally more MFS transporter encoding genes than Saccharomyces cerevisiae, S. pombe, and Neurospora crassa. The drug H+ (12 and 14 spanners) sub-families are also proportionally greater than in the other species. Although the numbers of ABC transporter encoding genes are comparable, again the Aspergillus spp. have more ABC transporters related to multidrug permease than the other fungal species.
Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Aspergillus fumigatus/efeitos dos fármacos , Farmacorresistência Fúngica , Ergosterol/biossíntese , Transportadores de Cassetes de Ligação de ATP/genética , Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Aspergillus fumigatus/metabolismo , Azóis/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Paracoccidioides brasiliensis, a thermodimorphic fungus, is the causative agent of paracoccidioidomycosis (PCM), the most prevalent systemic mycosis in Latin America. Pathogenicity appears to be intimately related to the dimorphic transition from the hyphal to the yeast form, which is induced by a shift from environmental temperature to the temperature of the mammalian host. Little information is available on the P. brasiliensis genes that are necessary during the pathogenic phase. We have therefore undertaken Suppression Subtraction Hybridization (SSH) and macroarray analyses with the aim of identifying genes that are preferentially expressed in the yeast phase. Genes identified by both procedures as being more highly expressed in the yeast phase are involved in basic metabolism, signal transduction, growth and morphogenesis, and sulfur metabolism. In order to test whether the observed changes in gene expression reflect the differences between the growth conditions used to obtain the two morphological forms rather than differences intrinsic to the cell types, we performed real-time RT-PCR experiments using RNAs derived from both yeast cells and mycelia that had been cultured at 37 degrees C and 26 degrees C in either complete medium (YPD or Sabouraud) or minimal medium. Twenty genes, including AGS1 (alpha-1,3-glucan synthase) and TSA1 (thiol-specific antioxidant), were shown to be more highly expressed in the yeast cells than in the hyphae. Although their levels of expression could be different in rich and minimal media, there was a general tendency for these genes to be more highly expressed in the yeast cells.
Assuntos
DNA Complementar/análise , DNA Fúngico/análise , Perfilação da Expressão Gênica , Genes Fúngicos/fisiologia , Paracoccidioides/genética , DNA Complementar/isolamento & purificação , Regulação Fúngica da Expressão Gênica , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae/genética , Técnica de SubtraçãoRESUMO
Chloroplast DNA (cpDNA) diversity was examined using PCR-RFLP to study phylogenetic relationships in Ananas and related genera. One hundred fifteen accessions representing the seven Ananas species and seven other Bromelioideae including the neighboring monospecific genus Pseudananas, two Pitcairnioideae, and one Tillandsioideae were included in the study. Eight primers designed from cpDNA were used for generating fragments. Restriction by 18 endonucleases generated 255 variable fragments. Dissimilarities were calculated from the resulting matrix using the Sokal and Michener index and the neighbor-joining method was used to reconstruct the diversity tree. Phylogenetic reconstruction was attempted using Wagner parsimony. Phenetic and cladistic analyses gave consistent results. They confirm the basal position of Bromelia in the Bromelioideae. Ananas and Pseudananas form a monophyletic group, with three strongly supported sub-groups, two of which are geographically consistent. The majority of Ananas parguazensis accessions constitute a northern group restricted to the Rio Negro and Orinoco basins in Brazil. The tetraploid Pseudananas sagenarius joins the diploid Ananas fritzmuelleri to constitute a southern group. The third and largest group, which includes all remaining species plus some accessions of A. parguazensis and intermediate phenotypes, is the most widespread and its distribution overlaps those of the northern and southern groups. Ananas ananassoides is dominant in this sub-group and highly variable. Its close relationship to all cultivated species supports the hypothesis that this species is the wild ancestor of the domesticated pineapple. The data indicate that gene flow is common within this group and scarcer with both the first and second groups. Comparison of cpDNA data with published genomic DNA data point to the hybrid origin of Ananas bracteatus and support the autopolyploidy of Pseudananas. The Ananas-Pseudananas group structure and distribution are consistent and we propose a scenario based on the refugia hypothesis to explain our data. These results and hypotheses bring some interesting points to consider in the current discussion on Ananas taxonomy.
Assuntos
Bromeliaceae/genética , DNA de Cloroplastos/genética , Filogenia , Bromeliaceae/classificação , Evolução Molecular , Variação Genética , Geografia , Haplótipos/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , América do SulRESUMO
The crude alkaloidal extract of Zanthoxylum chiloperone stem bark exhibited in vitro activity against various strains of Leishmania ssp. at 100 microg/ml. Two active major constituents were isolated and identified as canthin-6-one and 5-methoxycanthin-6-one. The effect of these compounds was also tested in an in vivo assay using BALB/c mice infected with Leishmania amazonensis. The mice were treated for 5 weeks postinfection with these alkaloids by oral (14 days) or intralesional route (4 days) at 10 mg/kg daily. The reference drug, N-methylglucamine antimonate was administered by subcutaneous injections at 100 mg/kg for 10 days. Intralesional administration of canthin-6-one reduced the parasite burden but not significantly when it was compared with the untreated group, while the reference drug reduced by 91% the parasite loads in the lesion.
Assuntos
Alcaloides/uso terapêutico , Carbolinas , Alcaloides Indólicos/uso terapêutico , Indóis/uso terapêutico , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Naftiridinas/uso terapêutico , Fitoterapia , Tripanossomicidas/uso terapêutico , Zanthoxylum , Alcaloides/química , Animais , Feminino , Alcaloides Indólicos/química , Indóis/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Naftiridinas/química , Preparações de Plantas/química , Preparações de Plantas/uso terapêutico , Tripanossomicidas/químicaRESUMO
It was reported previously that 2-n-propylquinoline was active against the epimastigote form of Trypanosoma cruzi. The effects of oral treatments with benznidazole and 2-n-propylquinoline were evaluated in Balb/c mice infected with T. cruzi chronically. The reference drug and 2-n-propylquinoline were administered 60 days post-infection for 30 days at 25 mg/mL. At 35 days post-treatment, the serological tests (ELISA) of the 2-n- propylquinoline-treated mice were significantly different from the controls (p = 0.01) and the benznidazole-treated mice (p = 0.03), while this was not the case at 85 days post-treatment. These results are encouraging for continuing the investigation of other analogues of 2-n-propylquinoline in experimental chronic Chagas' disease.
Assuntos
Doença de Chagas/tratamento farmacológico , Fitoterapia , Quinolinas/uso terapêutico , Rutaceae , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/imunologia , Animais , Doença Crônica , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nitroimidazóis/uso terapêutico , Extratos Vegetais/uso terapêutico , Trypanosoma cruzi/isolamento & purificaçãoRESUMO
Wild germplasm of domesticated crops is a source of genetic variation little utilized in breeding programs. Interspecific crosses can potentially uncover novel gene combinations that can be important for quantitative trait analysis. The combined use of wide crosses and genetic maps of chromosomal regions associated with quantitative traits can be used to broaden the genetic basis of rice breeding programs. Oryza glumaepatula is a diploid (AA genome) wild rice species native from South and Central America. A genetic map was constructed with 162 PCR-based markers (155 microsatellite and 7 STS markers) using a backcross population derived from the cross O. glumaepatula, accession RS-16 from the Brazilian Amazon Region x O. sativa BG-90-2, an elite rice inbred line. The map included 47 new SSR markers developed from an O. glumaepatula genomic library enriched for AG/TC sequences. All SSR markers were able to amplify the O. sativa genome, indicating a high degree of SSR flanking region conservation between O. glumaepatula and O. sativa species. The map covered 1500.4 cM, with an average of one marker every 10 cM. Despite some chromosomes being more densely mapped, the overall coverage was similar to other maps developed for rice. The advantage to construct a SSR-based map is to permit the combination of the speed of the PCR reaction, and the codominant nature of the SSR marker, facilitating the QTL analysis and marker assisted selection for rice breeding programs.
Assuntos
Mapeamento Cromossômico/métodos , Genes de Plantas , Repetições de Microssatélites , Oryza/genética , Cruzamentos Genéticos , Primers do DNA , DNA de Plantas/genética , Biblioteca Gênica , Ligação Genética , Reação em Cadeia da PolimeraseRESUMO
A sample of American wild rice and other accessions of the genus Oryza were studied at polymorphic regions of nuclear, mitochondrial, and chloroplastic genomes. First, flow cytometry, genome-specific RAPD markers, and chromosome counting were utilized to verify the original ploidy and classification of 230 accessions studied. Based on these methods, 8% of the accessions were considered to be misclassified either taxonomically or as a result of contamination. Second, a fine resolution analysis was conducted at genomic regions sampled at random by RAPD markers and at specific sites of the chloroplast and mitochondrial DNA by cleaved amplified polymorphic sequence (CAPS) analysis. Phylogenetic trees resulting from phenetic and cladistic analyses of RAPD, cpDNA, and mtDNA polymorphisms were obtained. The results indicated that the American diploid species O. glumaepatula should be considered an individual species, distinct from O. rufipogon, and confirmed that the American tetraploid species (O. alta, O. grandiglumis, and O. latifolia) belong to the O. officinalis complex. The data indicate that these species should still be treated as a group rather than as three distinct species and that their closest relative is a CC-genome species. It was estimated that the diploid and tetraploid American species diverged from O. sativa - O. nivara (AA genome) and CC- and BBCC-genome species, respectively, 20 million years ago.
Assuntos
Núcleo Celular/genética , Citoplasma/genética , DNA de Plantas/genética , Oryza/classificação , Oryza/genética , Filogenia , Ploidias , Sequência de Bases , Cromossomos/genética , DNA de Cloroplastos/genética , DNA Mitocondrial/genética , Diploide , Evolução Molecular , Citometria de Fluxo , Genoma de Planta , América do Norte , Oryza/citologia , Polimorfismo Genético/genética , Poliploidia , Técnica de Amplificação ao Acaso de DNA Polimórfico , América do SulRESUMO
We have demonstrated that the hepatic function may have an important role in the development of tolerance to the pyrogenic effect induced by endotoxin. To further investigate if the role of the hepatic function in the development of tolerance also extends to that induced by other pyrogenic stimuli, we investigated the effect of galactosamine, a specific inhibitor of the hepatic protein synthesis, on the development of tolerance to the pyrogenic effect induced by muramyl dipeptide (MDP) in rats. Pyrogenic tolerance was observed after the second intravenous or intraperitoneal injection of MDP (500 microgram/kg), 24 h after the first injection, similar to what was observed with endotoxin. Pyrogenic tolerance was abolished when galactosamine (300 mg/kg ip) was injected simultaneously with MDP (500 microgram/kg iv) on the first day. When uridine (600 mg/kg ip) was administered simultaneously with galactosamine (300 mg/kg ip) and the first injection of MDP (500 microgram/kg ip), pyrogenic tolerance was again observed after the second injection of the peptidoglycan. In conclusion, the hepatic function may not be important only for the development of tolerance to endotoxin, but also to a totally different pyrogenic stimulus such as MDP.