Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Impressões digitais de DNA e RNA através de AP-PCR em Entamoeba histolytica

Differences were detected in the gene expression of strains of E. histolytica using RNA (RAP-PCR) and DNA fingerprinting (RAPD). Analysis of the electrophoretic profiles of the gels revealed some polymorphic markers that could be used in the individual characterization of the strains. The 260 bands generated by using five different primers for RAP-PCR, as well as RAPD, were employed in the construction of dendograms. The dendogram obtained based on the RAPD products permitted the distinction of symptomatic and asymptomatic isolates, as well the correlation between the polymorphism exhibited and the virulence of the strains. The dendogram obtained for the RAP-PCR products did not show a correlation with the virulence of the strains but revealed a high degree of intraspecific transcriptional variability that could be related to other biological features, whether or not these are involved in the pathogenesis of amebiasis.Diferenças na expressão gênica de cepas de E. histolytica foram obtidas pelo "fingerprinting" de RNA (RAP-PCR) e DNA (RAPD). A análise do perfil eletroforético do gel revelou alguns marcadores polimórficos que poderiam ser usados na caracterização individual das cepas. As 260 bandas geradas pela utilização de cinco primers diferentes, tanto no RAP-PCR, quanto no RAPD foram empregadas na construção de dendogramas. O dendograma obtido com os produtos do RAPD permitiu a distinção das cepas isoladas de pacientes sintomáticos e assintomáticos, além de correlacionar o polimorfismo exibido com a virulência das mesmas. O dendograma obtido com os produtos do RAP-PCR não apresentou correlação com a virulência das cepas, mas revelou uma exuberante variabilidade transcricional intra-específica, que pode estar relacionada a outros caracteres biológicos envolvidos, ou não, na patogênese da amebíase

Sulphur(lone pair)…π interactions with FAD in flavoenzymes

The interactions of π-systems with lone-pairs of electrons are known and have been described in biological systems, involving lone-pairs derived from metals, metalloids, sulphur, oxygen and nitrogen. This study describes a bibliographic survey of the disulphide-bound sulphur(lonepair) interactions with -systems residing in the flavin adenine dinucleotide (FAD) cofactor oxidoreductase enzymes (flavoenzymes). Thus, of the 172 oxidoreductase enzymes evaluated for gamma-S(lone pair)…π(FAD) interactions, 96 proteins (56%) exhibited these interactions corresponding; 61% of 350 the constituent monomers featured at least one gamma-S(lone pair)…π(FAD) interaction. Two main points of association between the S(lone pair) and the isoalloxazine moiety of FAD were identified, namely at the centroid of the bond linking the uracil and pyrazine rings (60% ), and the centroid of the uracil ring (37%). Reflecting the nature of the secondary structure in three prominent classes of oxidoreductase enzymes: glutathione disulphide reductases (GR; 21 proteins), trypanothione disulphide reductases (TR, 14) and sulfhydryl oxidases (SOX, 22), the approach of the gamma-S(lone-pair) to the FAD residue was to the si-face of the isoalloxazine ring system, i.e. to the opposite side as the carbonyl residue, for all GR and TR examples, and to the re-face for all SOX examples. Finally, the attractive nature of the gamma-S(lone pair)…π(FAD) interactions was confirmed qualitatively by an examination of the non-covalent interaction plots

Prevalência de enteroparasitoses em crianças de creches públicas da cidade de Belo Horizonte, Minas Gerais, Brasil

The objective of this study was to verify the occurrence of intestinal parasites in 3 to 6-year-old children from daycare centers maintained by the municipal government of Belo Horizonte, Minas Gerais, Brazil. Coproparasitological tests performed in 472 children have shown that 24.6% of them had some type of parasites, 6.6% of the children having more than one type. Among protozoa, Entamoeba coli (14.0%) and G. duodenalis (9.5%) were the most prevalent, whereas Ascaris lumbricoides (3.0%) and Trichuris trichiura (1.1%) were the most frequent among the helminths. Thus, we can observe that intestinal parasites still represent a serious public health problem in Belo Horizonte, especially among children and in areas where the socioeconomic conditions are less favorable.O objetivo deste trabalho foi verificar a ocorrência de parasitos intestinais em crianças de 3 a 6 anos de idade, oriundas de creches mantidas pela Prefeitura Municipal de Belo Horizonte, Minas Gerais, Brasil. Exames coproparasitológicos realizados em 472 crianças demonstraram que 24,6% apresentavam algum tipo de parasitose, sendo que 6,6% apresentavam mais de um parasito. Entre os protozoários, Entamoeba coli (14,0%) e G. duodenalis (9,5%) foram os mais prevalentes, enquanto Ascaris lumbricoides (3,0%) e Trichuris trichiura (1,1%) foram os mais encontrados entre os helmintos. Desta forma, observa-se que as parasitoses intestinais ainda são um problema de saúde pública em Belo Horizonte, principalmente entre a população infantil e em áreas onde as condições sócio-econômicas são menos favoráveis

N′-[(2E)-3-Phenyl­prop-2-eno­yl]benzo­hydrazide

In the title compound, C16H14N2O2, the conformation about the C=C bond is E, and the two amide groups are effectively orthogonal [the C—N—N—C torsion angle is 104.5 (2)°]. In the crystal structure, the amide groups groups associate via N–H⋯O hydrogen bonding, forming supra­molecular tapes with undulating topology along the c-axis direction

5-(3-Nitro­benz­yl)-1,3,4-thia­diazol-2-amine

In the title mol­ecule, C9H8N4O2S, the dihedral angle between the thia­diazole and benzene rings is 73.92 (8)° and the thia­diazole group S atom is orientated towards the benzene ring, the central S—C—C—C torsion angle being 45.44 (18)°. In the crystal, supra­molecular tapes mediated by N—H⋯N hydrogen bonds and comprising alternating eight-membered {⋯HNCN}2 and 10-membered {⋯HNH⋯NN}2 synthons are formed along [010]. The tapes are consolidated into a three-dimensional network by a combination of C—H⋯O, C—H⋯S and C—H⋯π inter­action

(2E)-N′-[(E)-4-Chloro­benzyl­idene]-3-phenyl­prop-2-enohydrazide monohydrate

The conformation about each of the imine and ethene bonds in the title hydrazide hydrate, C16H13ClN2O·H2O, is E. The hydrazide mol­ecule is approximately planar (r.m.s. deviation of the 20 non-H atoms = 0.172 Å). The most significant twist occurs about the ethene bond [C—C=C—C = 164.1 (5)°] and the dihedral angle formed between the benzene rings is 5.3 (2)°]. In the crystal, the presence of N—H⋯Ow and O—H⋯Oc (× 2; w = water and c = carbon­yl) hydrogen bonds leads to a supra­molecular array in the bc plane

Large emissions from floodplain trees close the Amazon methane budget

Wetlands are the largest global source of atmospheric methane (CH4), a potent greenhouse gas. However, methane emission inventories from the Amazon floodplain, the largest natural geographic source of CH4 in the tropics, consistently underestimate the atmospheric burden of CH4 determined via remote sensing and inversion modelling, pointing to a major gap in our understanding of the contribution of these ecosystems to CH4 emissions. Here we report CH4 fluxes from the stems of 2,357 individual Amazonian floodplain trees from 13 locations across the central Amazon basin. We find that escape of soil gas through wetland trees is the dominant source of regional CH4 emissions. Methane fluxes from Amazon tree stems were up to 200 times larger than emissions reported for temperate wet forests6 and tropical peat swamp forests, representing the largest non-ebullitive wetland fluxes observed. Emissions from trees had an average stable carbon isotope value (δ13C) of −66.2 ± 6.4 per mil, consistent with a soil biogenic origin. We estimate that floodplain trees emit 15.1 ± 1.8 to 21.2 ± 2.5 teragrams of CH4 a year, in addition to the 20.5 ± 5.3 teragrams a year emitted regionally from other sources. Furthermore, we provide a ‘top-down’ regional estimate of CH4 emissions of 42.7 ± 5.6 teragrams of CH4 a year for the Amazon basin, based on regular vertical lower-troposphere CH4 profiles covering the period 2010–2013. We find close agreement between our ‘top-down’ and combined ‘bottom-up’ estimates, indicating that large CH4 emissions from trees adapted to permanent or seasonal inundation can account for the emission source that is required to close the Amazon CH4 budget. Our findings demonstrate the importance of tree stem surfaces in mediating approximately half of all wetland CH4 emissions in the Amazon floodplain, a region that represents up to one-third of the global wetland CH4 source when trees are combined with other emission sources