Sustainable development 20 years on from the earth summit: progress, gaps and strategic guidelines for Latin America and the Caribbean

Includes bibliography

Polishing of water treated by a biological process with heterogeneous photocatalysis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Measurement of melatonin in body fluids: Standards, protocols and procedures

Background and Purpose: The circadian rhythm of melatonin in saliva or plasma, or of the melatonin metabolite 6-sulfatoxymelatonin (a6MTs) in urine, is a defining feature of suprachiasmatic nucleus (SCN) function, the body's endogenous oscillatory pacemaker. The primary objective of this review is to ascertain the clinical benefits and limitations of current methodologies employed for detection and quantification of melatonin in biological fluids and tissues. Data Identification: A search of the English-language literature (Medline) and a systematic review of published articles were carried out. Study Selection: Articles that specified both the methodology for quantifying melatonin and indicated the clinical purpose were chosen for inclusion in the review. Data Extraction: The authors critically evaluated the methodological issues associated with various tools and techniques (e.g. standards, protocols, and procedures). Results of Data Synthesis: Melatonin measurements are useful for evaluating problems related to the onset or offset of sleep and for assessing phase delays or advances of rhythms in entrained individuals. They have also become an important tool for psychiatric diagnosis, their use being recommended for phase typing in patients suffering from sleep and mood disorders. Additionally, there has been a continuous interest in the use of melatonin as a marker for neoplasms of the pineal region. Melatonin decreases such as found with aging are or post pinealectomy can cause alterations in the sleep/wake cycle. The development of sensitive and selective methods for the precise detection of melatonin in tissues and fluids has increasingly been shown to have direct relevance for clinical decision making. Conclusions: Due to melatonin's low concentration, as well as the coexistence of numerous other compounds in the blood, the routine determination of melatonin has been an analytical challenge. The available evidence indicates however that these challenges can be overcome and consequently that evaluation of melatonin's presence and activity can be an accessible and useful tool for clinical diagnosis. © Springer-Verlag 2010.

Policies and practices for the use of information and communications technologies (ICTs) in education in Latin America and the Caribbean

Includes bibliography

Comparative immature morphology of Brazilian fire ants (Hymenoptera: Formicidae: Solenopsis)

Although common in Brazil, the biology of the fire ant Solenopsis saevissima (Smith) is still poorly studied. Larval descriptions are useful to genus-level ant systematics and sometimes to species-level taxonomy. This study presents a detailed description of juveniles of S. saevissima from Brazil, which were compared with Brazilian specimens of Solenopsis invicta Buren, Solenopsis geminata (Fabricius), and Solenopsis altipunctata Pitts. Different larval instars were separated by diagnostic morphological traits which were confirmed by observing moults. Reproductive larvae could be easily sorted by their distinctive body dimensions and shape. Contrary to previous reports on this species, the larvae of S. saevissima proved to be generally identical to those of S. invicta, while a few specimens resembled those of other close species, such as Solenopsis megergates Trager. Mature larvae thus presented considerable intraspecific variation in some characters recently proposed to aid fire ant species separation (morphology of head hairs). © 2012 Eduardo Gonalves Paterson Fox et al.

Nutritional evaluation of soy yoghurt in comparison to soymilk and commercial milk yoghurt. Effect of fermentation on soy protein

Soymilk was fermented using Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. The soy yoghurt produced was evaluated in comparison to soymilk and commercial milk yoghurt by biological evaluation, rat growth, nitrogen balance assays and microbiological methods. Trypsin inhibitor activity and chemical composition were also determined for all samples. For the soy yoghurt, the growth and nitrogen balance values were not different from the control diet, but the nitrogen balance values were higher than for the soymilk, without significant difference in terms of growth assays. Compared to the commercial yoghurt, Net Protein Ratio and Nitrogen Utilization values were lower, but the Protein Efficiency Ratio, Biological Value and Net Protein Utilization values were equivalent, and for digestibility assays the best results were obtained with the soy yoghurt. The results indicated that soy yoghurt represents a good protein alternative to milk yoghurt and casein. The protein quality of soymilk evidently increased during the fermentation process using Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus, including a reduction in trypsin inhibitor levels of about 30%.

Anatomy of the floral nectaries of some neotropical Salacioideae (Celastraceae)

Floral nectaries have contributed to the systematics of different taxonomic groups. Since those of the neotropical genera included in subfamily Salacioideae-Cheiloclinium Miers, Peritassa Miers, Salacia L. and Tontelea Aubl.-have different forms and positions, we explored their anatomy to delimit more precisely the genera of subfamily Salacioideae. Buds and open flowers of six species were treated following the usual techniques in plant anatomy. The obtained data were helpful in characterizing the floral nectary anatomy of the studied species. Furthermore, some features such as form, position and surface of nectaries; form of their epidermal cells; presence and distribution of stomata; occurrence of idioblasts containing druses in the nectariferous parenchyma; and absence of nectary vascularization can contribute to the taxonomy and phylogeny of the Salacioideae studied. In most of the studied species the nectar is probably released by both the stomata and the nectary epidermal surface. In Cheiloclinium cognatum, the structure acknowledged as nectary is actually a vestigial tissue and the functions of attracting and rewarding pollinators has phylogenetically migrated to the stigmatic region. The druses and phenolic substances observed in the nectariferous parenchyma probably help defend flowers against herbivore attacks. The minute size of the nectaries of Salacioideae may explain the absence of vascularization. The floral nectaries of Salacia elliptica are epithelial while those of the other species are mesenchymal. © 2012 Springer-Verlag Wien.

Association of IGF1 and KDM5A polymorphisms with performance, fatness and carcass traits in chickens

Two functional and positional candidate genes were selected in a region of chicken chromosome 1 (GGA1), based on their biological roles, and also where several quantitative trait loci (QTL) have been mapped and associated with performance, fatness and carcass traits in chickens. The insulin-like growth factor 1 (IGF1) gene has been associated with several physiological functions related to growth. The lysine (K)-specific demethylase 5A (KDM5A) gene participates in the epigenetic regulation of genes involved with the cell cycle. Our objective was to find associations of selected single-nucleotide polymorphisms (SNPs) in these genes with performance, fatness and carcass traits in 165 F2 chickens from a resource population. In the IGF1 gene, 17 SNPs were detected, and in the KDM5A gene, nine SNPs were detected. IGF1 SNP c. 47673G > A was associated with body weight and haematocrit percentage, and also with feed intake and percentages of abdominal fat and gizzard genotype × sex interactions. KDM5A SNP c. 34208C > T genotype × sex interaction affected body weight, feed intake, percentages of abdominal fat (p = 0. 0001), carcass, gizzard and haematocrit. A strong association of the diplotype × sex interaction (p < 0. 0001) with abdominal fat was observed, and also associations with body weight, feed intake, percentages of carcass, drums and thighs, gizzard and haematocrit. Our findings suggest that the KDM5A gene might play an important role in the abdominal fat deposition in chickens. The IGF1 and KDM5A genes are strong candidates to explain the QTL mapped in this region of GGA1. © 2012 Institute of Plant Genetics, Polish Academy of Sciences, Poznan.

Chemoprotective activity of the isoflavones, genistein and daidzein on mutagenicity induced by direct and indirect mutagens in cultured HTC cells

Isoflavones are phenolic compounds widely distributed in plants and found in a high percentage in soybeans. They have important biological properties and are regarded as potential chemopreventive agents. The aim of this study was to verify the preventive effect of two soy isoflavones (genistein and daidzein) by a micronucleus assay, analysis of GST activity, and real-time RT-PCR analysis of GSTa2 gene expression. Mutagens of direct (doxorubicin) and indirect (2-aminoanthracene) DNA damage were used. Hepatoma cells (HTC) were treated with genistein or daidzein for 26 h at noncytotoxic concentrations; 10 μM when alone, and 0.1, 1.0 and 10 μM when combined with genotoxic agents. The micronucleus test demonstrated that both isoflavones alone had no genotoxic effect. Genistein showed antimutagenic effects at 10 μM with both direct and indirect DNA damage agents. On phase II enzyme regulation, the current study indicated an increase in total cytoplasmic GST activity in response to genistein and daidzein at 10 μM supplementation. However, the mRNA levels of GSTa2 isozymes were not differentially modulated by genistein or daidzein. The results point to an in vitro antimutagenic activity of genistein against direct and indirect DNA damage-induced mutagenicity. © 2012 Springer Science+Business Media B.V.

Chrysobalanaceae: Secondary metabolites, ethnopharmacology and pharmacological potential

Many Chrysobalanaceae species, in special Licania and Parinari, are widely used in folk medicine to treat several diseases. This review describes some aspects of their ethnopharmacology potential, biological activities and the secondary metabolites reported so far for Chrysobalanaceae. The chemical constituents of this family include triterpenoids, diterpenoids, steroids and phenylpropanoids like flavonoids as well as chromones derivatives. © 2012 Springer Science+Business Media Dordrecht.

Xylo-oligosaccharides from lignocellulosic materials: Chemical structure, health benefits and production by chemical and enzymatic hydrolysis

Currently, there is worldwide interest in the technological use of agro-industrial residues as a renewable source of food and biofuels. Lignocellulosic materials (LCMs) are a rich source of cellulose and hemicellulose. Hemicellulose is rich in xylan, a polysaccharide used to develop technology for producing alcohol, xylose, xylitol and xylo-oligosaccharides (XOSs). The XOSs are unusual oligosaccharides whose main constituent is xylose linked by β 1-4 bonds. The XOS applications described in this paper highlight that they are considered soluble dietary fibers that have prebiotic activity, favoring the improvement of bowel functions and immune function and having antimicrobial and other health benefits. These effects open a new perspective on potential applications for animal production and human consumption. The raw materials that are rich in hemicellulose include sugar cane bagasse, corncobs, rice husks, olive pits, barley straw, tobacco stalk, cotton stalk, sunflower stalk and wheat straw. The XOS-yielding treatments that have been studied include acid hydrolysis, alkaline hydrolysis, auto-hydrolysis and enzymatic hydrolysis, but the breaking of bonds present in these compounds is relatively difficult and costly, thus limiting the production of XOS. To obviate this limitation, a thorough evaluation of the most convenient methods and the opportunities for innovation in this area is needed. Another challenge is the screening and taxonomy of microorganisms that produce the xylanolytic complex and enzymes and reaction mechanisms involved. Among the standing out microorganisms involved in lignocellulose degradation are Trichoderma harzianum, Cellulosimicrobium cellulans, Penicillium janczewskii, Penicillium echinulatu, Trichoderma reesei and Aspergillus awamori. The enzyme complex predominantly comprises endoxylanase and enzymes that remove hemicellulose side groups such as the acetyl group. The complex has low β-xylosidase activities because β-xylosidase stimulates the production of xylose instead of XOS; xylose, in turn, inhibits the enzymes that produce XOS. The enzymatic conversion of xylan in XOS is the preferred route for the food industries because of problems associated with chemical technologies (e.g., acid hydrolysis) due to the release of toxic and undesired products, such as furfural. The improvement of the bioprocess for XOS production and its benefits for several applications are discussed in this study. © 2012 Elsevier Ltd.

Molecular phylogeny of Moenkhausia (Characidae) inferred from mitochondrial and nuclear DNA evidence

Moenkhausia is one of the most speciose genera in Characidae, currently composed of 75 nominal species of small fishes distributed across South American hydrographic basins, primarily the Amazon and Guyanas. Despite the large number of described species, studies involving a substantial number of its species designed to better understand their relationships and putative monophyly are still lacking. In this study, we analysed a large number of species of Moenkhausia to test the monophyly of the genus based on the phylogenetic analysis of DNA sequences of two mitochondrial and three nuclear genes. The in-group included 29 species of Moenkhausia, and the out-group was composed of representatives of Characidae and other members of Characiformes. All species of Moenkhausia belong to the same clade (Clade C); however, they appear distributed in five monophyletic groups along with other different genera, which means that Moenkhausia is polyphyletic and indicates the necessity of an extensive revision of the group. © 2013 Blackwell Verlag GmbH.

Dimerization of aurein 1.2: Effects in structure, antimicrobial activity and aggregation of Cândida albicans cells

Antimicrobial peptides (AMPs) are a promising solution to face the antibiotic-resistant problem because they display little or no resistance effects. Dimeric analogues of select AMPs have shown pharmacotechnical advantages, making these molecules promising candidates for the development of novel antibiotic agents. Here, we evaluate the effects of dimerization on the structure and biological activity of the AMP aurein 1.2 (AU). AU and the C- and N-terminal dimers, (AU)2K and E(AU)2, respectively, were synthesized by solid-phase peptide synthesis. Circular dichroism spectra indicated that E(AU)2 has a coiled coil structure in water while (AU)2K has an α-helix structure. In contrast, AU displayed typical spectra for disordered structures. In LPC micelles, all peptides acquired a high amount of α-helix structure. Hemolytic and vesicle permeabilization assays showed that AU has a concentration dependence activity, while this effect was less pronounced for dimeric versions, suggesting that dimerization may change the mechanism of action of AU. Notably, the antimicrobial activity against bacteria and yeast decreased with dimerization. However, dimeric peptides promoted the aggregation of C. albicans. The ability to aggregate yeast cells makes dimeric versions of AU attractive candidates to inhibit the adhesion of C. albicans to biological targets and medical devices, preventing disease caused by this fungus. © 2013 Springer-Verlag Wien.

Mangrove habitat partitioning by Ucides cordatus (Ucididae): Effects of the degree of tidal flooding and tree-species composition during its life cycle

Environmental factors strongly affect mangrove crabs, and some factors modulate population structure and habitat partitioning during the crabs' life cycle. However, the effect of these environmental factors on habitat selection by mangrove crabs is still unknown. We evaluated habitat selection by the mangrove crab Ucides cordatus in mangrove forests with different degrees of predominance of Rhizophora mangle, Laguncularia racemosa or Avicennia schaueriana, two tidal flooding levels (less- and more-flooded), and two biological periods (breeding and non-breeding seasons). Sampling was conducted in four mangrove forests with different influences of these biotic and abiotic parameters. We used the data for sex ratio to explain environmental partitioning by this species. Females predominated in R. mangle mangroves, independently of the biological period (breeding or non-breeding seasons), and males predominated only in the less-flooded L. racemosa mangroves. The flooding level affected the sex ratio of U. cordatus, with a predominance of males in less-flooded mangroves, independently of the biological period; and a gender balance in the more-flooded mangroves only during the breeding season. Outside the breeding season, the largest specimens were recorded in the R. mangle mangroves, but in the breeding season, the largest crabs were recorded in the L. racemosa mangroves with a higher level of flooding. These results suggest that tree-species composition and tidal flooding level can have a significant effect on the habitat partitioning of sexes and sizes of the mangrove crab U. cordatus both during and outside the breeding season. © 2012 Springer-Verlag and AWI.

Historical biogeography and cryptic diversity in the Callichthyinae (Siluriformes, Callichthyidae)

The family Callichthyidae, divided into the subfamilies Corydoradinae and Callichthyinae, contains more than 200 species of armoured catfishes distributed throughout the Neotropics, as well as fossil species dating from the Palaeocene. Both subfamilies are very widely distributed throughout the continent, with some species ranges extending across multiple hypothesized biogeographical barriers. Species with such vast geographical ranges could be made up of multiple cryptic populations that are genetically distinct and have diverged over time. Although relationships among Callichthyinae genera have been thoroughly investigated, the historical biogeography of the Callichthyinae and the presence of species complexes have yet to be examined. Furthermore, there is a lack of fossil-calibrated molecular phylogenies providing a time frame for the evolution of the Callichthyinae. Here, we present a novel molecular data set for all Callichthyinae genera composed of partial sequences of mitochondrial and nuclear markers. These data were used to construct a fossil-calibrated tree for the Callichthyinae and to reconstruct patterns of spatiotemporal evolution. All phylogenetic analyses [Bayesian, maximum likelihood and maximum parsimony (MP)] resulted in a single fully resolved and well-supported hypothesis for the Callichthyinae, where Dianema is the sister group of all the remaining genera. Results suggest that the ancestry of most Callichthyinae genera originated in the Amazonas basin, with a number of subsequent ancestral dispersal events between adjacent basins. High divergences in sequences and time were observed for several samples of Hoplosternum littorale, Megalechis picta and Callichthys callichthys, suggesting that these species may contain cryptic diversity. The results highlight the need for a taxonomic revision of species complexes within the Callichthyinae, which may reveal more diversity within this relatively species-poor lineage. © 2013 Blackwell Verlag GmbH.