The role of the segmentation gene hairy in Tribolium

Hairy stripes in Tribolium are generated during blastoderm and germ band extension, but a direct role for Tc-h in trunk segmentation was not found. We have studied here several aspects of hairy function and expression in Tribolium, to further elucidate its role. First, we show that there is no functional redundancy with other hairy paralogues in Tribolium. Second, we cloned the hairy orthologue from Tribolium confusum and show that its expression mimics that of Tribolium castaneum, implying that stripe expression should be functional in some way. Third, we show that the dynamics of stripe formation in the growth zone is not compatible with an oscillatory mechanism comparable to the one driving the expression of hairy homologues in vertebrates. Fourth, we use parental RNAi experiments to study Tc-h function and we find that mandible and labium are particularly sensitive to loss of Tc-h, reminiscent of a pair-rule function in the head region. In addition, lack of Tc-h leads to cell death in the gnathal region at later embryonic stages, resulting in a detachment of the head. Cell death patterns are also altered in the midline. Finally, we have analysed the effect of Tc-h knockdown on two of the target genes of hairy in Drosophila, namely fushi tarazu and paired. We find that the trunk expression of Tc-h is required to regulate Tc-ftz, although Tc-ftz is itself also not required for trunk segmentation in Tribolium. Our results imply that there is considerable divergence in hairy function between Tribolium and Drosophila

FGF Signaling Pathway in the Developing Chick Lung: Expression and Inhibition Studies

Background: Fibroblast growth factors (FGF) are essential key players during embryonic development. Through their specific cognate receptors (FGFR) they activate intracellular cascades, finely regulated by modulators such as Sprouty. Several FGF ligands (FGF1, 2, 7, 9, 10 and 18) signaling through the four known FGFRs, have been implicated in lung morphogenesis. Although much is known about mammalian lung, so far, the avian model has not been explored for lung studies. Methodology/Principal Findings: In this study we provide the first description of fgf10, fgfr1-4 and spry2 expression patterns in early stages of chick lung development by in situ hybridization and observe that they are expressed similarly to their mammalian counterparts. Furthermore, aiming to determine a role for FGF signaling in chick lung development, in vitro FGFR inhibition studies were performed. Lung explants treated with an FGF receptor antagonist (SU5402) presented an impairment of secondary branch formation after 48 h of culture; moreover, abnormal lung growth with a cystic appearance of secondary bronchi and reduction of the mesenchymal tissue was observed. Branching and morphometric analysis of lung explants confirmed that FGFR inhibition impaired branching morphogenesis and induced a significant reduction of the mesenchyme. Conclusions/Significance: This work demonstrates that FGFRs are essential for the epithelial-mesenchymal interactions tha

Topographical analysis of the subependymal zone neurogenic niche

The emerging model for the adult subependymal zone (SEZ) cell population indicates that neuronal diversity is not generated from a uniform pool of stem cells but rather from diverse and spatially confined stem cell populations. Hence, when analysing SEZ proliferation, the topography along the anterior-posterior and dorsal-ventral axes must be taken into account. However, to date, no studies have assessed SEZ proliferation according to topographical specificities and, additionally, SEZ studies in animal models of neurological/psychiatric disorders often fail to clearly specify the SEZ coordinates. This may render difficult the comparison between studies and yield contradictory results. More so, by focusing in a single spatial dimension of the SEZ, relevant findings might pass unnoticed. In this study we characterized the neural stem cell/progenitor population and its proliferation rates throughout the rat SEZ anterior-posterior and dorsal-ventral axes. We found that SEZ proliferation decreases along the anterior-posterior axis and that proliferative rates vary considerably according to the position in the dorsal-ventral axis. These were associated with relevant gradients in the neuroblasts and in the neural stem cell populations throughout the dorsal-ventral axis. In addition, we observed spatially dependent differences in BrdU/Ki67 ratios that suggest a high variability in the proliferation rate and cell cycle length throughout the SEZ; in accordance, estimation of the cell cycle length of the neuroblasts revealed shorter cell cycles at the dorsolateral SEZ. These findings highlight the need to establish standardized procedures of SEZ analysis. Herein we propose an anatomical division of the SEZ that should be considered in future studies addressing proliferation in this neural stem cell niche.Fundação para a Ciência e a Tecnologia (FCT

The prevalence of self-reported underuse of medications due to cost for the elderly: Results from seven European urban communities

Background: The aim of this study was to evaluate the prevalence of self-reported underuse of medications due to procurement costs amongst older persons from seven European urban communities. Methods: The data were collected in a cross-sectional study (“ABUEL, Elder abuse: A multinational prevalence survey”) in 2009. Randomly selected people aged 60–84 years (n = 4,467) from seven urban communities: Stuttgart (Germany), Athens (Greece), Ancona (Italy), Kaunas (Lithuania), Porto (Portugal), Granada (Spain) and Stockholm (Sweden) were interviewed. Response rate - 45.2 %. Ethical permission was received in each country. Results: The results indicate that 3.6 % (n = 162) of the respondents self-reported refraining from buying prescribed medications due to cost. The highest prevalence of this problem was identified in Lithuania (15.7 %, n = 99) and Portugal (4.3 %, n = 28). Other countries reported lower percentages of refraining from buying medications (Germany – 2.0 %, Italy – 1.6 %, Sweden – 1.0 %, Greece – 0.6 %, Spain – 0.3 %). Females refrained more often from buying medications than males (2.6 % vs. 4.4 %, p < 0.0001). The prevalence of this refraining tended to increase with economic hardship. Discussion: These differences between countries can be only partly described by the financing of health-care systems. In spite of the presence of cost reimbursement mechanisms, patients need to make co-payments (or in some cases to pay the full price) for prescribed medications. This indicates that the purchasing power of people in 10.1186/s12913-015-1089-4 the particular country can play a major role and be related with the economic situation in the country. Lithuania, which has reported the highest refrain rates, had the lowest gross domestic product (at the time of conducting this study) of all participating countries in the study. Conclusions: Refraining from buying the prescribed medications due to cost is a problem for women and men in respect to ageing people in Europe. Prevalence varies by country, sex, and economic hardship.The ABUEL was supported by the Executive Agency for Health and Consumers (EAHC) (Grant No., A/2007123) and participating institutions

DNA microarray profiling of genes differentially regulated by the histone deacetylase inhibitors vorinostat and LBH589 in colon cancer cell lines

<p>Abstract</p> <p>Background</p> <p>Despite the significant progress made in colon cancer chemotherapy, advanced disease remains largely incurable and novel efficacious chemotherapies are urgently needed. Histone deacetylase inhibitors (HDACi) represent a novel class of agents which have demonstrated promising preclinical activity and are undergoing clinical evaluation in colon cancer. The goal of this study was to identify genes in colon cancer cells that are differentially regulated by two clinically advanced hydroxamic acid HDACi, vorinostat and LBH589 to provide rationale for novel drug combination partners and identify a core set of HDACi-regulated genes.</p> <p>Methods</p> <p>HCT116 and HT29 colon cancer cells were treated with LBH589 or vorinostat and growth inhibition, acetylation status and apoptosis were analyzed in response to treatment using MTS, Western blotting and flow cytometric analyses. In addition, gene expression was analyzed using the Illumina Human-6 V2 BeadChip array and Ingenuity^®Pathway Analysis.</p> <p>Results</p> <p>Treatment with either vorinostat or LBH589 rapidly induced histone acetylation, cell cycle arrest and inhibited the growth of both HCT116 and HT29 cells. Bioinformatic analysis of the microarray profiling revealed significant similarity in the genes altered in expression following treatment with the two HDACi tested within each cell line. However, analysis of genes that were altered in expression in the HCT116 and HT29 cells revealed cell-line-specific responses to HDACi treatment. In addition a core cassette of 11 genes modulated by both vorinostat and LBH589 were identified in both colon cancer cell lines analyzed.</p> <p>Conclusion</p> <p>This study identified HDACi-induced alterations in critical genes involved in nucleotide metabolism, angiogenesis, mitosis and cell survival which may represent potential intervention points for novel therapeutic combinations in colon cancer. This information will assist in the identification of novel pathways and targets that are modulated by HDACi, providing much-needed information on HDACi mechanism of action and providing rationale for novel drug combination partners. We identified a core signature of 11 genes which were modulated by both vorinostat and LBH589 in a similar manner in both cell lines. These core genes will assist in the development and validation of a common gene set which may represent a molecular signature of HDAC inhibition in colon cancer.</p

Echinococcus granulosus Antigen B Structure: Subunit Composition and Oligomeric States

Antigen B (AgB) is the major secretory protein of the Echinococcus granulosus hydatid cyst, the causative agent of cystic hydatid disease. Structurally, AgB is a multisubunit protein formed by 8-kDa subunits, but it is not known which subunits are secreted by a single parasite (cyst) and how they interact in the formation of distinct AgB oligomeric states. Here, we investigated AgB subunit composition and oligomeric states in individual samples from bovine and human cysts. We identified AgB8/1, AgB8/2, AgB8/3 and AgB8/4 subunits in AgB oligomers of all samples analyzed. Quantitative and qualitative differences in the expression of AgB subunits were observed within and between samples. Using recombinant subunits as models, we showed that AgB subunits form distinct oligomeric states, with a rAgB8/3>rAgB8/2>rAgB8/1 maximum size relation. We also demonstrated by different experimental approaches that rAgB8/3 oligomers are more similar, both in size and morphology, to those observed for E. granulosus AgB. Overall, we provided experimental evidences that AgB is composed of different subunits within a single cyst, and that subunits have different abundances and oligomerization properties. These issues are important for the understanding of AgB expression and structure variations, and their impact for the host-parasite cross-talk

Long-Distance Signals Are Required for Morphogenesis of the Regenerating Xenopus Tadpole Tail, as Shown by Femtosecond-Laser Ablation

tadpoles has recently emerged as an important model for these studies; we explored the role of the spinal cord during tadpole tail regeneration.Using ultrafast lasers to ablate cells, and Geometric Morphometrics to quantitatively analyze regenerate morphology, we explored the influence of different cell populations. For at least twenty-four hours after amputation (hpa), laser-induced damage to the dorsal midline affected the morphology of the regenerated tail; damage induced 48 hpa or later did not. Targeting different positions along the anterior-posterior (AP) axis caused different shape changes in the regenerate. Interestingly, damaging two positions affected regenerate morphology in a qualitatively different way than did damaging either position alone. Quantitative comparison of regenerate shapes provided strong evidence against a gradient and for the existence of position-specific morphogenetic information along the entire AP axis.We infer that there is a conduit of morphology-influencing information that requires a continuous dorsal midline, particularly an undamaged spinal cord. Contrary to expectation, this information is not in a gradient and it is not localized to the regeneration bud. We present a model of morphogenetic information flow from tissue undamaged by amputation and conclude that studies of information coming from far outside the amputation plane and regeneration bud will be critical for understanding regeneration and for translating fundamental understanding into biomedical approaches