Comparative genetic diversity of wild and captive populations of the bare-faced curassow (Crax fasciolata) based on cross-species microsatellite markers: implications for conservation and management.

The bare-faced curassow (Crax fasciolata) is a large Neotropical bird that suffers anthropogenic pressure across much of its range. A captive population is maintained for conservation management, although there has been no genetic screening of stocks. Based on the six microsatellite markers developed for Crax globulosa, the genetic variability of C. fasciolata and possible differences between a wild and a captive population were investigated. Only three loci were polymorphic, with a total of 27 alleles. More than half of these alleles were private to the wild (n = 8) or captive (n = 7) populations. Significant deviations from Hardy-Weinberg equilibrium were restricted to the captive population. Despite the number of private alleles, genetic drift has probably promoted differentiation between populations. Our results indicate that wild C. fasciolata populations are genetically impoverished and structured, but species-specific microsatellite markers will be necessary for a more reliable assessment of the species' genetic diversity.

Patterns and processes of diversification in a widespread and ecologically diverse avian group, the buteonine hawks (Aves, Accipitridae).

Buteonine hawks represent one of the most diverse groups in the Accipitridae, with 58 species distributed in a variety of habitats on almost all continents. Variations in migratory behavior, remarkable dispersal capability, and unusual diversity in Central and South America make buteonine hawks an excellent model for studies in avian evolution. To evaluate the history of their global radiation, we used an integrative approach that coupled estimation of the phylogeny using a large sequence database (based on 6411 bp of mitochondrial markers and one nuclear intron from 54 species), divergence time estimates, and ancestral state reconstructions. Our findings suggest that Neotropical buteonines resulted from a long evolutionary process that began in the Miocene and extended to the Pleistocene. Colonization of the Nearctic, and eventually the Old World, occurred from South America, promoted by the evolution of seasonal movements and development of land bridges. Migratory behavior evolved several times and may have contributed not only to colonization of the Holarctic, but also derivation of insular species. In the Neotropics, diversification of the buteonines included four disjunction events across the Andes. Adaptation of monophyletic taxa to wet environments occurred more than once, and some relationships indicate an evolutionary connection among mangroves, coastal and várzea environments. On the other hand, groups occupying the same biome, forest, or open vegetation habitats are not monophyletic. Refuges or sea-level changes or a combination of both was responsible for recent speciation in Amazonian taxa. In view of the lack of concordance between phylogeny and classification, we propose numerous taxonomic changes.

The historical biogeography of Pteroglossus aracaris (Aves, Piciformes, Ramphastidae) based on Bayesian analysis of mitochondrial DNA sequences

Most Neotropical birds, including Pteroglossus aracaris, do not have an adequate fossil record to be used as time constraints in molecular dating. Hence, the evolutionary timeframe of the avian biota can only be inferred using alternative time constraints. We applied a Bayesian relaxed clock approach to propose an alternative interpretation for the historical biogeography of Pteroglossus based on mitochondrial DNA sequences, using different combinations of outgroups and time constraints obtained from outgroup fossils, vicariant barriers and molecular time estimates. The results indicated that outgroup choice has little effect on the Bayesian posterior distribution of divergence times within Pteroglossus, that geological and molecular time constraints seem equally suitable to estimate the Bayesian posterior distribution of divergence times for Pteroglossus, and that the fossil record alone overestimates divergence times within the fossil-lacking ingroup. The Bayesian estimates of divergence times suggest that the radiation of Pteroglossus occurred from the Late Miocene to the Pliocene (three times older than estimated by the ôstandardõ mitochondrial rate of 2% sequence divergence per million years), likely triggered by Andean uplift, multiple episodes of marine transgressions in South America, and formation of present-day river basins. The time estimates are in agreement with other Neotropical taxa with similar geographic distributions.

Polyphyly of the hawk genera Leucopternis and Buteogallus (Aves, Accipitridae): multiple habitat shifts during the Neotropical buteonine diversification.

BACKGROUND: The family Accipitridae (hawks, eagles and Old World vultures) represents a large radiation of predatory birds with an almost global distribution, although most species of this family occur in the Neotropics. Despite great morphological and ecological diversity, the evolutionary relationships in the family have been poorly explored at all taxonomic levels. Using sequences from four mitochondrial genes (12S, ATP8, ATP6, and ND6), we reconstructed the phylogeny of the Neotropical forest hawk genus Leucopternis and most of the allied genera of Neotropical buteonines. Our goals were to infer the evolutionary relationships among species of Leucopternis, estimate their relationships to other buteonine genera, evaluate the phylogenetic significance of the white and black plumage patterns common to most Leucopternis species, and assess general patterns of diversification of the group with respect to species' affiliations with Neotropical regions and habitats. RESULTS: Our molecular phylogeny for the genus Leucopternis and its allies disagrees sharply with traditional taxonomic arrangements for the group, and we present new hypotheses of relationships for a number of species. The mtDNA phylogenetic trees derived from analysis of the combined data posit a polyphyletic relationship among species of Leucopternis, Buteogallus and Buteo. Three highly supported clades containing Leucopternis species were recovered in our phylogenetic reconstructions. The first clade consisted of the sister pairs L. lacernulatus and Buteogallus meridionalis, and Buteogallus urubitinga and Harpyhaliaetus coronatus, in addition to L. schistaceus and L. plumbeus. The second clade included the sister pair Leucopternis albicollis and L. occidentalis as well as L. polionotus. The third lineage comprised the sister pair L. melanops and L. kuhli, in addition to L. semiplumbeus and Buteo buteo. According to our results, the white and black plumage patterns have evolved at least twice in the group. Furthermore, species found to the east and west of the Andes (cis-Andean and trans-Andean, respectively) are not reciprocally monophyletic, nor are forest and non-forest species. CONCLUSION: The polyphyly of Leucopternis, Buteogallus and Buteo establishes a lack of concordance of current Accipitridae taxonomy with the mtDNA phylogeny for the group, and points to the need for further phylogenetic analysis at all taxonomic levels in the family as also suggested by other recent analyses. Habitat shifts, as well as cis- and trans-Andean disjunctions, took place more than once during buteonine diversification in the Neotropical region. Overemphasis of the black and white plumage patterns has led to questionable conclusions regarding the relationships of Leucopternis species, and suggests more generally that plumage characters should be used with considerable caution in the taxonomic evaluation of the Accipitridae.

Molecular phylogenetics and biogeography of Neotropical piping guans (Aves: Galliformes): Pipile Bonaparte, 1856 is synonym of Aburria Reichenbach, 1853.

The Cracidae are Neotropical galliform birds with 11 genera currently recognized. To investigate the questioned validity of Pipile Bonaparte, 1856 and the monotypic Aburria Reichenbach, 1853 as separate genera, we gathered data from 2727 bp of mitochondrial DNA (cytochrome b, ND2 and control region) and 151 osteological characters. Our phylogenetic analyses of DNA sequences indicated that Aburria aburri is embedded within Pipile. Also, genetic distances between Aburria and any Pipile species are equivalent to the distances estimated for other congeneric cracid species, which genus status is not doubtful. Although the osteological characters do not have phylogenetic signal to solve the phylogenetic relationships at species level, five synapomorphies were found for Aburria and Pipile. Therefore, we suggest that Pipile should be merged with Aburria, which is the oldest described genus. We estimated that speciation in this group occurred in the Plio-Pleistocene, concordant with other birds, primates and rodents that have similar geographic distribution, and proposed a diversification hypothesis based on the occurrence of sea transgressions and the formation of the Amazon Lagoon. Therefore, we conclude that these palaeogeographic events may have contributed to Neotropical taxa diversification to a greater extent than previously suspected.

Molecular architecture and rates of DNA substitutions of the mitochondrial control region of cracid birds.

The control region (CR) plays an important role in replication and transcription in the mitochondrial genome. Its supposedly high rate of DNA substitution makes it a suitable marker for studies of population and closely related species. Three domains can be identified in CR, each having its own characteristics regarding base composition, pattern of variability and rate of DNA substitution. We sequenced the complete CR for 27 cracids, including all 11 genera to characterize its molecular organization, describe patterns of DNA substitution along the gene, and estimate absolute rates of DNA substitution. Our results show that cracid CR organization and patterns of DNA substitution are typical of other birds. Conserved blocks C and B, fused CSB2/3, and a putative segment for bidirectional replication not usually present in birds were identified in cracids. We also suggest a new delimitation for domains to allow better comparisons among CRs at different taxonomic ranking. Our estimates of absolute rates of DNA substitution show that, in general, CR evolves at a rate slower than that of two protein-coding genes (CR, 0.14%-0.3%; ND2, 0.37%-0.47%; and cytochrome b, 0.29%-0.35% per site per million years within genera). Within CR domains, rates within genera ranged from 0.05% to 0.8% per site per million years.

Diversification of Ramphastinae (Aves, Ramphastidae) prior to the Cretaceous/Tertiary boundary as shown by molecular clock of mtDNA sequences

Partial cytochrome b and 12S rDNA mitochondrial DNA sequences of eight representatives of the Ramphastidae family were analyzed. We applied the linearized tree method to identify sequences evolving at similar rates and estimated the divergence times among some of the taxa analyzed. After excluding Ramphastos tucanus and Capito dayi from our data set, the remaining taxa presented a constant rate of DNA substitution, and branch lengths could be re-estimated with a clock constraint using the maximum likelihood method. Branch lengths were calibrated assuming that Galliformes and Piciformes split around 100 million years ago (mya). Our results indicate that Ramphastinae, and probably Capitoninae, diverged from other Piciformes in the Late Cretaceous (82 mya), suggesting that Piciformes is another avian order that survived the mass extinction event occurred 65 mya at the Cretaceous/Tertiary (K/T) boundary. The divergence times estimated within the Ramphastinae genera cover the period from the Middle Eocene (around 47 mya) through the Late Miocene (9.5 mya). Our estimate of divergence time is coincidental with the split of the African and the South American continents and other intense geologic activities and modifications of the areas which correspond to the current Neotropics. These events might have influenced the diversification of Ramphastinae in South America.

Combined nuclear and mitochondrial DNA sequences resolve generic relationships within the Cracidae (Galliformes, Aves).

The Cracidae is one of the most endangered and distinctive bird families in the Neotropics, yet the higher relationships among taxa remain uncertain. The molecular phylogeny of its 11 genera was inferred using 10,678 analyzable sites (5,412 from seven different mitochondrial segments and 5,266 sites from four nuclear genes). We performed combinability tests to check conflicts in phylogenetic signals of separate genes and genomes. Phylogenetic analysis showed that the unrooted tree of ((curassows, horned guan) (guans, chachalacas)) was favored by most data partitions and that different data partitions provided support for different parts of the tree. In particular, the concatenated mitochondrial DNA (mtDNA) genes resolved shallower nodes, whereas the combined nuclear sequences resolved the basal connections among the major clades of curassows, horned guan, chachalacas, and guans. Therefore, we decided that for the Cracidae all data should be combined for phylogenetic analysis. Maximum parsimony (MP), maximum likelihood (ML), and Bayesian analyses of this large data set produced similar trees. The MP tree indicated that guans are the sister group to (horned guan, (curassows, chachalacas)), whereas the ML and Bayesian analysis recovered a tree where the horned guan is a sister clade to curassows, and these two clades had the chachalacas as a sister group. Parametric bootstrapping showed that alternative trees previously proposed for the cracid genera are significantly less likely than our estimate of their relationships. A likelihood ratio test of the hypothesis of a molecular clock for cracid mtDNA sequences using the optimal ML topology did not reject rate constancy of substitutions through time. We estimated cracids to have originated between 64 and 90 million years ago (MYA), with a mean estimate of 76 MYA. Diversification of the genera occurred approximately 41-3 MYA, corresponding with periods of global climate change and other Earth history events that likely promoted divergences of higher level taxa.

DNA fingerprinting in the rare black-fronted piping guan Pipile jacutinga (Cracidae, Aves)

Brazilian Cracidae are threatened by heavy environmental degradation and hunting. The Black-fronted piping-guan (Pipile jacutinga) used to inhabit the Atlantic coastal highland forests. Now it occurs in limited forest areas where it is rarely seen. Interative management, including captive breeding, might be an important action for its survival. We present data on DNA fingerprinting using Jeffreys' human minisatlelite probes 33.6 and 33.15. Our results show that this technique is useful for estimating the genetic variability of natural populations and may help to maintain the genetic variability of captive bred individuals of this species. A linkage analysis of the fingerprint profiles in a family with 7 chicks was performed (to estimate the number of independently segregating loci detected in this species) and at least 16 highly polymorphic independent loci were identified for each probe.

Hipertermia materna como provavel fator tetarogenico / Maternal hipertemy like provable factor tetarogenic

Estudos experimentais em animais tem demonstrado que a hipertermia no primeiro terco da gestacao induz a erros no fechamento do tubo neural e disrupcao do desenvolvimento do macico facial. Na especie humana o mesmo espectro malformativo tem sido relatado em neonatos cujas maes tem historico positivo de hipertermia no inicio da gestacao. Diferentes fatores podem ser responsaveis pela hipertermia materna: doencas infecciosas, banhos de sauna e banhos de imersao prolongados e muito quentes. O proposito estudado neste trabalho apresenta labio leporino bilateral e palato fendido, microftalmia, coloboma de iris, apendices auriculares bilaterais, pavilhao auditivo de implantacao anomala, lesao isodensa supra-selar e historico gestacional de febre alta no inicio da gravidez.Estas caracteristicas sao interpretadas como disrupcao do desenvolvimento da linha media da face, dos primeiros e segundo arcos branquiais, e heteropatias neuronias, compativeis com o diagnostico de disrupcao do desenvolvimento por hipertermia materna. A febre alta materna foi causada provavelmente pelo Dengue .

Macrossomia, macrocrania e incoordenaçäo motora da infância: síndrome de sotos (McKusick 11755); Estudo de 7 casos e revisäo de aspectos clínicos de 198 casos publicados / Macrosomia, macrocrania and motor disordes in childhood: sotos syndrome (McKusick 11755), report of 7 cases and review of clinical aspects of 198 report cases

Crianças com síndrome de Sotos apresentam aceleraçäo do crescimento, macrocrania, padröes acromegalóides e dificuldades iniciais no desenvolvimento neuropsicomotor. A delineaçäo da síndrome e o diagnóstico diferencial estäo baseados na avaliaçäo das características clínicas e no histórico evolutivo desses pacientes. Sete pacientes com síndrome de Sotos säo descritos, bem como revistas as características clínicas presentes em 198 pacientes da literatura. As dificuldades motoras presentes durante a primeira infância nos pacientes com síndrome de Sotos säo responsáveis pelo mau desempenho destas crianças nos testes de QI. A estimulaçäo especializada deve ser encorajada para ajustar os afetados a superarem suas dificuldades iniciais

In vitro cytogenetic effects of cannabidiol on human lymphocyte cultures

Investigou-se o efeito in vitro do canabidiol (CBD) sobre o índice mitótico e a frequência de células com aberraçöes cromossômicas numéricas e/ou estruturais, em culturas de linfócitos humanos. Em uma primeira fase o CBD foi dissolvido em álcool etílico absoluto (0,01 ml/ml de meio) nas concentraçöes de 0,001, 0,01 0,1, e 10,0 microng de CBD/ml de meio e, na segunda fase, o etanol foi evaporado antes de ser adicionado o meio de cultura. O efeito clastogênico do CBD foi maior quando associado ao álcool. A açäo do etanol foi predominantemente anti-mitogênica enquanto o CBD teve efeito mais nítido sobre a produçäo de células com aberraçöes cromossômicas. Após a evaporaçäo do etanol, a proporçäo de células com aberraçöes cromossômicas estruturais manteve uma relaçäo aproximadamente crescente com o aumento da taxa de CBD