Molecular phylogeny of the New World Dipsadidae (Serpentes: Colubroidea): a reappraisal

We present a phylogenetic analysis of the New World dipsadids based on an expanded data matrix that includes 246 terminal taxa including 196 dipsadids. The species are sampled for eight genes (12S, 16S, cytb, nd2, nd4, bdnf, c‐mos, rag2). The data are explored using two distinct optimality procedures—maximum parsimony and maximum likelihood—and two alignment strategies—dynamic homology and static homology. Two previously unsampled dipsadid genera, Sordellina and Rhachidelus, are now included in the analysis. The definitions of the genera, Erythrolamprus, Clelia, Hypsirhynchus, Philodryas and Phimophis, and the tribes Alsophiini, Echinantherini and Conophiini, are revised. In order to maintain monophyly, the genus Umbrivaga is synonymized with Erythrolamprus, and two new genera are erected to accommodate Phimophis iglesiasi and Clelia rustica, as well as their closely related species. The West Indian genera Schwartzophis, Darlingtonia, Antillophis and Ocyophis are resurrected. © The Willi Hennig Society 2012.     

Association of 25-Hydroxyvitamin D status and genetic variation in the vitamin D metabolic pathway with FEV1 in the Framingham Heart Study

Background

Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.

Methods

We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV₁) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV₁ in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV₁ in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.

Results

We found a positive cross-sectional association between 25(OH)D and FEV₁ in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV₁ in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV₁ (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV₁ in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).

Conclusions

Serum 25(OH)D status was associated with cross-sectional FEV₁, but not longitudinal change in FEV₁. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV₁ and is a promising candidate gene for further studies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users.     

Molecular phylogeny and biogeography of the eastern Tapaculos (Aves: Rhinocryptidae: Scytalopus, Eleoscytalopus): Cryptic diversification in Brazilian Atlantic Forest

Scytalopus and the recently erected Eleoscytalopus are among the Neotropical groups of birds whose taxonomy is most difficult to resolve given their very conservative morphology. We investigated the phylogeny and species limits of Eleoscytalopus and the eastern Scytalopus using two mitochondrial genes and two nuclear introns of multiple individuals from all species of these groups. The eastern Scytalopus are separated in three well defined clades also supported by morphological or vocal characteristics, although the relationships between these clades could not be resolved. We found several allopatric and very divergent lineages in these genera whose characteristics are consistent with species-level divergence, especially in S. speluncae. The great divergence between E. psychopompus and its sister species supports the former as a valid species. Our results corroborate the importance of the Bahia refuge as an avian center of endemism.     

Toxicological Effects of the Different Substances in Tobacco Smoke on Human Embryonic Development by a Systems Chemo-Biology Approach

The physiological and molecular effects of tobacco smoke in adult humans and the development of cancer have been well described. In contrast, how tobacco smoke affects embryonic development remains poorly understood. Morphological studies of the fetuses of smoking pregnant women have shown various physical deformities induced by constant fetal exposure to tobacco components, especially nicotine. In addition, nicotine exposure decreases fetal body weight and bone/cartilage growth in addition to decreasing cranial diameter and tibia length. Unfortunately, the molecular pathways leading to these morphological anomalies are not completely understood. In this study, we applied interactome data mining tools and small compound interaction networks to elucidate possible molecular pathways associated with the effects of tobacco smoke components during embryonic development in pregnant female smokers. Our analysis showed a relationship between nicotine and 50 additional harmful substances involved in a variety of biological process that can cause abnormal proliferation, impaired cell differentiation, and increased oxidative stress. We also describe how nicotine can negatively affect retinoic acid signaling and cell differentiation through inhibition of retinoic acid receptors. In addition, nicotine causes a stress reaction and/or a pro-inflammatory response that inhibits the agonistic action of retinoic acid. Moreover, we show that the effect of cigarette smoke on the developing fetus could represent systemic and aggressive impacts in the short term, causing malformations during certain stages of development. Our work provides the first approach describing how different tobacco constituents affect a broad range of biological process in human embryonic development.     

Hypolipidemic and antiatherosclerotic potential of Pleurotus ostreatus, cultived by submerged fermentation in the high-fat diet fed rats

The ability of Pleurotus ostreatus biomass, cultived by submerged fermentation, to produce beneficial effect on lipid profile and macrophages activity during a high-fat diet (HFD) for a long-term intake was investigated. Blood samples were collected through cardiac puncture to measure the plasma cholesterol, triglycerides, low-density protein (LDL), high-density protein (HDL), aspartate aminotransferase (AST) activity, urea-blood urea nitrogen (BUN)/creatinine ratio of rats fed on an HFD for 4 months. Dosage of lipid hydroperoxides was carried out on methanolic extract of liver tissue. Peritoneal macrophages activity was evaluated in relation to the superoxide anion, hydrogen peroxide and nitric oxide production, phagocytosis and lysosomal volume. The administration of P. ostreatus significantly altered the lipid profile and oxidative stress as related to the LDL and triglycerides decrease and inhibitory effects on superoxide anion and hydrogen peroxide production. All findings of this study lead us to suggest that the P. ostreatus maybe a beneficial agent in the hyperlipidemia and atherosclerosis treatments.     

Inter-male aggression with regard to polygynous mating system in Pampean grassland mouse, Akodon azarae (Cricetidae: Sigmodontinae)

Based on the hypothesis that, in Akodon azarae, polygyny operates through female defence, we studied inter-male aggression in order to test the following predictions: during the breeding period (1) resident males are more aggressive than intruder males in the presence of females (FP), and (2) aggressive behaviour is independent of male condition (resident or intruder) in the absence of females (FA). To test our predictions, we used the resident male behavioural response towards an intruder male in relation to FP or FA. We conducted 30 encounters in FP and 27 in FA in 0.79-m² round enclosures placed in the Espinal Reservation. Our results support the prediction that, in FP, the intensity of aggressive behaviour exhibited by males varied in relation to resident or intruder condition. Resident males showed high levels of aggression towards intruders, and intruders exhibited the greatest values of submissive behaviours with residents. In FA, the intensity of aggressive behaviour did not vary in relation to resident or intruder condition. Both resident and intruder males exhibited low aggressive behaviour and inter-male encounters resulted mainly in non interactive behaviours. Our results support the hypothesis that, in A. azarae, the polygynous mating system operates through female defence.     

Hybridization Between Neotropical Primates with Contrasting Sexual Dichromatism

International Journal of Primatology - Hybridization is relatively well documented among Old World primates, but poorly investigated among New World monkeys. We investigated hybridization between...     

Phylogeography of the Petunia integrifolia complex in southern Brazil

In this study, we evaluated the genetic diversity of the Petunia integrifolia species group using a phylogeographical approach, and attempted to understand better its diversification and taxonomy. Plants from five morphological groups were collected, covering a large part of the geographical distribution of most of the species. Two major clades were found in the phylogenetic tree, and an additional lineage, corresponding to P. inflata, was found in the haplotype network obtained for plastid markers. All three lineages are clearly delimited geographically, but, with the exception of P. inflata, the morphological groups were not genetically distinct. Our results suggest that a population expansion after a size reduction resulted in the establishment of two distinct and allopatric groups c. 0.5 Mya, one group occurring in a geologically ancient area, and the other occurring in areas that were under the influence of a series of marine transgressions/regressions at the end of the Pleistocene. These two clades are evolutionarily significant units with significantly different allele frequencies in their nuclear genome and reciprocal monophyly in maternal, uniparentally inherited markers. All our results suggest that the morphology‐based taxonomy in this group does not reflect its evolutionary history, and revision of its species limits should incorporate the distribution of the genetic diversity. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174 , 199–213.     

PHLDA1 (pleckstrin homology-like domain,family A,member 1) knockdown promotes migration and invasion of MCF10A breast epithelial cells

PHLDA1 (pleckstrin homology-like domain, family A, member 1) is a multifunctional protein that plays distinct roles in several biological processes including cell death and therefore its altered expression has been identified in different types of cancer. Progressively loss of PHLDA1 was found in primary and metastatic melanoma while its overexpression was reported in intestinal and pancreatic tumors. Previous work from our group showed that negative expression of PHLDA1 protein was a strong predictor of poor prognosis for breast cancer disease. However, the function of PHLDA1 in mammary epithelial cells and the tumorigenic process of the breast is unclear. To dissect PHLDA1 role in human breast epithelial cells, we generated a clone of MCF10A cells with stable knockdown of PHLDA1 and performed functional studies. To achieve reduced PHLDA1 expression we used shRNA plasmid transfection and then changes in cell morphology and biological behavior were assessed. We found that PHLDA1 downregulation induced marked morphological alterations in MCF10A cells, such as changes in cell-to-cell adhesion pattern and cytoskeleton reorganization. Regarding cell behavior, MCF10A cells with reduced expression of PHLDA1 showed higher proliferative rate and migration ability in comparison with control cells. We also found that MCF10A cells with PHLDA1 knockdown acquired invasive properties, as evaluated by transwell Matrigel invasion assay and showed enhanced colony-forming ability and irregular growth in low attachment condition. Altogether, our results indicate that PHLDA1 downregulation in MCF10A cells leads to morphological changes and a more aggressive behavior.