Australian Sphingidae – DNA Barcodes Challenge Current Species Boundaries and Distributions

© 2014 Rougerie et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article

Serine-Selective Bioconjugation.

This Communication reports the first general method for rapid, chemoselective, and modular functionalization of serine residues in native polypeptides, which uses a reagent platform based on the P(V) oxidation state. This redox-economical approach can be used to append nearly any kind of cargo onto serine, generating a stable, benign, and hydrophilic phosphorothioate linkage. The method tolerates all other known nucleophilic functional groups of naturally occurring proteinogenic amino acids. A variety of applications can be envisaged by this expansion of the toolbox of site-selective bioconjugation methods

Exchange flow between open water and floating vegetation

This study describes the exchange flow between a region with open water and a region with a partial-depth porous obstruction, which represents the thermally-driven exchange that occurs between open water and floating vegetation. The partial-depth porous obstruction represents the root layer, which does not penetrate to the bed. Initially, a vertical wall separates the two regions, with fluid of higher density in the obstructed region and fluid of lower density in the open region. This density difference represents the influence of differential solar heating due to shading by the vegetation. For a range of root density and root depths, the velocity distribution is measured in the lab using PIV. When the vertical wall is removed, the less dense water flows into the obstructed region at the surface. This surface flow bifurcates into two layers, one flowing directly through the root layer and one flowing beneath the root layer. A flow directed out of the vegetated region occurs at the bed. A model is developed that predicts the flow rates within each layer based on energy considerations. The experiments and model together suggest that at time- and length-scales relevant to the field, the flow structure for any root layer porosity approaches that of a fully blocked layer, for which the exchange flow occurs only beneath the root layer.National Science Foundation (U.S.) (grant EAR0509658

Periostin Responds to Mechanical Stress and Tension by Activating the MTOR Signaling Pathway

Current knowledge about Periostin biology has expanded from its recognized functions in embryogenesis and bone metabolism to its roles in tissue repair and remodeling and its clinical implications in cancer. Emerging evidence suggests that Periostin plays a critical role in the mechanism of wound healing; however, the paracrine effect of Periostin in epithelial cell biology is still poorly understood. We found that epithelial cells are capable of producing endogenous Periostin that, unlike mesenchymal cell, cannot be secreted. Epithelial cells responded to Periostin paracrine stimuli by enhancing cellular migration and proliferation and by activating the mTOR signaling pathway. Interestingly, biomechanical stimulation of epithelial cells, which simulates tension forces that occur during initial steps of tissue healing, induced Periostin production and mTOR activation. The molecular association of Periostin and mTOR signaling was further dissected by administering rapamycin, a selective pharmacological inhibitor of mTOR, and by disruption of Raptor and Rictor scaffold proteins implicated in the regulation of mTORC1 and mTORC2 complex assembly. Both strategies resulted in ablation of Periostin-induced mitogenic and migratory activity. These results indicate that Periostin-induced epithelial migration and proliferation requires mTOR signaling. Collectively, our findings identify Periostin as a mechanical stress responsive molecule that is primarily secreted by fibroblasts during wound healing and expressed endogenously in epithelial cells resulting in the control of cellular physiology through a mechanism mediated by the mTOR signaling cascade.This work was funded by the National Institutes of Health (NIH/NCI) P50-CA97248 (University of Michigan Head and Neck SPORE)

Increased Expression of Musashi-1 Evidences Mesenchymal Repair in Maxillary Sinus Floor Elevation

This study aimed to analyze the expression of Musashi-1 (MSI1) in maxillary native bone and grafted bone after maxillary sinus floor elevation. To do so, fifty-seven bone biopsies from 45 participants were studied. Eighteen samples were collected from native bone while 39 were obtained 6 months after maxillary sinus grafting procedures. Musashi-1 was analyzed by immunohistochemistry and RT-PCR. MSI1 was detected in osteoblasts and osteocytes in 97.4% (38/39) of grafted areas. In native bone, MSI1 was detected in only 66.6% (12/18) of the biopsies, mainly in osteocytes. Detection of MSI1 was significantly higher in osteoprogenitor mesenchymal cells of grafted biopsies (p < 0.001) but minor in smooth muscle and endothelial cells; no expression was detected in adipocytes. The mesenchymal cells of the non-mineralized tissue of native bone showed very low nuclear expression of MSI1, in comparison to fusiform cells in grafted areas (0.28(0.13) vs. 2.10(0.14), respectively; p < 0.001). Additionally, the detection of MSI1 mRNA was significantly higher in biopsies from grafted areas than those from native bone (1.00(0.51) vs. 60.34(35.2), respectively; p = 0.029). Thus, our results regardig the significantly higher detection of Musashi-1 in grafted sites than in native bone reflects its importance in the remodeling/repair events that occur after maxillary sinus floor elevation in humans.This investigation was partially supported by Research Groups #CTS-138 and #CTS-1028 (Junta de Andalucía, Spain). MPM was supported by the Andalucía Talent Hub Program from the Andalusian Knowledge Agency (co-funded by the European Union’s Seventh Framework Program, Marie Skłodowska-Curie actions (COFUND – Grant Agreement n° 291780) and the Ministry of Economy, Innovation, Science and Employment of the Junta de Andalucía)

Reduced blood flow through intrapulmonary arteriovenous anastomoses at rest and during exercise in lowlanders during acclimatization to high altitude

Blood flow through intrapulmonary arteriovenous anastomoses (QIPAVA ) is elevated during exercise at sea level (SL) and at rest in acute normobaric hypoxia. Following high altitude (HA) acclimatization, resting QIPAVA is similar to SL, but it is unknown if this is true during exercise at HA. We reasoned that exercise at HA (5,050 m) would exacerbate QIPAVA due to heightened pulmonary arterial pressure. Using a supine cycle ergometer, seven healthy adults free from intracardiac shunts underwent an incremental exercise test at SL (25, 50, 75% of SL VO2peak ) and at HA (25, 50% of SL VO2peak ). Echocardiography was used to determine cardiac output (Q) and pulmonary artery systolic pressure (PASP) and agitated saline contrast was used to determine QIPAVA (bubble score; 0-5). The principal findings were: (1) Q was similar at SL-rest (3.9 +/- 0.47 l min-1 ) compared with HA-rest (4.5 +/- 0.49 l min-1 ; P = 0.382), but increased from rest during both SL and HA exercise (P < 0.001); (2) PASP increased from SL-rest (19.2 +/- 0.7 mmHg) to HA-rest (33.7 +/- 2.8 mmHg; P = 0.001) and, compared with SL, PASP was further elevated during HA exercise (P = 0.003); (3) QIPAVA was increased from SL-rest (0) to HA-rest (median = 1; P = 0.04) and increased from resting values during SL exercise (P < 0.05), but were unchanged during HA exercise (P = 0.91), despite significant increases in Q and PASP. Theoretical modeling of microbubble dissolution suggests that the lack of QIPAVA in response to exercise at HA is unlikely caused by saline contrast instability

Spatio-temporal variability in underwater light climate in a turbid river-floodplain system. Driving factors and estimation using Secchi disc

The underwater light climate has important effects on primary producers. The aim of this research was to evaluate its variability in a turbid river-floodplain system. Photosynthetically active radiation (PAR) was measured in the Middle Paraná River during different hydrological phases to (a) analyse the photosynthetically active radiation attenuation coefficient (k) and euphotic depth (Zeu) as well as their associations with optically active components and (b) develop and evaluate indices and regression models based on Secchi disc (SD) measurements to estimate k and Zeu. Values of k were higher in the fluvial system than in the floodplain and during low-water stage than high-water stage. Particulate components controlled the light climate variability. Chromophoric dissolved organic matter and chlorophyll-a had significant effects during floods. The estimation of k and Zeu was sensitive to temporal but not to spatial variations. The highest prediction accuracy was observed when using specific non-linear regressions for each hydrological phase, especially for Zeu estimation (low stage: k = 1.76 × SD−0.80, Zeu = 2.62 × 1/SD−0.80; high stage: k = 2.04 × SD−0.53, Zeu = 2.26 × 1/SD−0.53). The indices k × SD and Zeu/SD were significantly different from those proposed for clear water environments. It is concluded that temporal variations should be considered when estimating k and Zeu in turbid river-floodplain systems because of the temporal heterogeneity in optically active components. Considering that ecological implication of the light climate depends on Zeu:depth ratio, we propose to estimate Zeu instead of k. Finally, indices proposed for clear water environments are not recommended to be applied to turbid environments.Fil: Mayora, Gisela Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Devercelli, Melina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin

Cryptic species in a well-known habitat: applying taxonomics to the amphipod genus Epimeria (Crustacea, Peracarida)

Taxonomy plays a central role in biological sciences. It provides a communication system for scientists as it aims to enable correct identification of the studied organisms. As a consequence, species descriptions should seek to include as much available information as possible at species level to follow an integrative concept of ‘taxonomics’. Here, we describe the cryptic species Epimeria frankei sp. nov. from the North Sea, and also redescribe its sister species, Epimeria cornigera. The morphological information obtained is substantiated by DNA barcodes and complete nuclear 18S rRNA gene sequences. In addition, we provide, for the first time, full mitochondrial genome data as part of a metazoan species description for a holotype, as well as the neotype. This study represents the first successful implementation of the recently proposed concept of taxonomics, using data from highthroughput technologies for integrative taxonomic studies, allowing the highest level of confidence for both biodiversity and ecological research

Effects of platelet rich plasma (PRP) on human gingival fibroblast, osteoblast and periodontal ligament cell behaviour

The use of platelet rich plasma (PRP, GLO) has been used as an adjunct to various regenerative dental procedures. The aim of the present study was to characterize the influence of PRP on human gingival fibroblasts, periodontal ligament (PDL) cells and osteoblast cell behavior in vitro