Metatranscriptomics and Pyrosequencing Facilitate Discovery of Potential Viral Natural Enemies of the Invasive Caribbean Crazy Ant, Nylanderia pubens

BACKGROUND: Nylanderia pubens (Forel) is an invasive ant species that in recent years has developed into a serious nuisance problem in the Caribbean and United States. A rapidly expanding range, explosive localized population growth, and control difficulties have elevated this ant to pest status. Professional entomologists and the pest control industry in the United States are urgently trying to understand its biology and develop effective control methods. Currently, no known biological-based control agents are available for use in controlling N. pubens. METHODOLOGY AND PRINCIPAL FINDINGS: Metagenomics and pyrosequencing techniques were employed to examine the transcriptome of field-collected N. pubens colonies in an effort to identify virus infections with potential to serve as control agents against this pest ant. Pyrosequencing (454-platform) of a non-normalized N. pubens expression library generated 1,306,177 raw sequence reads comprising 450 Mbp. Assembly resulted in generation of 59,017 non-redundant sequences, including 27,348 contigs and 31,669 singlets. BLAST analysis of these non-redundant sequences identified 51 of potential viral origin. Additional analyses winnowed this list of potential viruses to three that appear to replicate in N. pubens. CONCLUSIONS: Pyrosequencing the transcriptome of field-collected samples of N. pubens has identified at least three sequences that are likely of viral origin and, in which, N. pubens serves as host. In addition, the N. pubens transcriptome provides a genetic resource for the scientific community which is especially important at this early stage of developing a knowledgebase for this new pest

Artificial tektites: an experimental technique for capturing the shapes of spinning drops

Determining the shapes of a rotating liquid droplet bound by surface tension is an archetypal problem in the study of the equilibrium shapes of a spinning and charged droplet, a problem that unites models of the stability of the atomic nucleus with the shapes of astronomical-scale, gravitationally-bound masses. The shapes of highly deformed droplets and their stability must be calculated numerically. Although the accuracy of such models has increased with the use of progressively more sophisticated computational techniques and increases in computing power, direct experimental verification is still lacking. Here we present an experimental technique for making wax models of these shapes using diamagnetic levitation. The wax models resemble splash-form tektites, glassy stones formed from molten rock ejected from asteroid impacts. Many tektites have elongated or ‘dumb-bell’ shapes due to their rotation mid-flight before solidification, just as we observe here. Measurements of the dimensions of our wax ‘artificial tektites’ show good agreement with equilibrium shapes calculated by our numerical model, and with previous models. These wax models provide the first direct experimental validation for numerical models of the equilibrium shapes of spinning droplets, of importance to fundamental physics and also to studies of tektite formation

Graphene Photonics and Optoelectronics

The richness of optical and electronic properties of graphene attracts enormous interest. Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability. So far, the main focus has been on fundamental physics and electronic devices. However, we believe its true potential to be in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultra-wide-band tunability. The rise of graphene in photonics and optoelectronics is shown by several recent results, ranging from solar cells and light emitting devices, to touch screens, photodetectors and ultrafast lasers. Here we review the state of the art in this emerging field.Comment: Review Nature Photonics, in pres

Viruses Associated with Ovarian Degeneration in Apis mellifera L. Queens

Queen fecundity is a critical issue for the health of honeybee (Apis mellifera L.) colonies, as she is the only reproductive female in the colony and responsible for the constant renewal of the worker bee population. Any factor affecting the queen's fecundity will stagnate colony development, increasing its susceptibility to opportunistic pathogens. We discovered a pathology affecting the ovaries, characterized by a yellow discoloration concentrated in the apex of the ovaries resulting from degenerative lesions in the follicles. In extreme cases, marked by intense discoloration, the majority of the ovarioles were affected and these cases were universally associated with egg-laying deficiencies in the queens. Microscopic examination of the degenerated follicles showed extensive paracrystal lattices of 30 nm icosahedral viral particles. A cDNA library from degenerated ovaries contained a high frequency of deformed wing virus (DWV) and Varroa destructor virus 1 (VDV-1) sequences, two common and closely related honeybee Iflaviruses. These could also be identified by in situ hybridization in various parts of the ovary. A large-scale survey for 10 distinct honeybee viruses showed that DWV and VDV-1 were by far the most prevalent honeybee viruses in queen populations, with distinctly higher prevalence in mated queens (100% and 67%, respectively for DWV and VDV-1) than in virgin queens (37% and 0%, respectively). Since very high viral titres could be recorded in the ovaries and abdomens of both functional and deficient queens, no significant correlation could be made between viral titre and ovarian degeneration or egg-laying deficiency among the wider population of queens. Although our data suggest that DWV and VDV-1 have a role in extreme cases of ovarian degeneration, infection of the ovaries by these viruses does not necessarily result in ovarian degeneration, even at high titres, and additional factors are likely to be involved in this pathology

Interaction between acrylic substrates and RAD16-I peptide in its self-assembling

[EN] Self-assembling peptides (SAP) are widely used as scaffolds themselves, and recently as fillers of microporous scaffolds, where the former provides a cell-friendly nanoenvironment and the latter improves its mechanical properties. The characterization of the interaction between these short peptides and the scaffold material is crucial to assess the potential of such a combined system. In this work, the interaction between poly(ethyl acrylate) (PEA) and 90/10 ethyl acrylate-acrylic acid copolymer P(EAcoAAc) with the SAP RAD16-I has been followed using a bidimensional simplified model. By means of the techniques of choice (congo red staining, atomic force microscopy (AFM), and contact angle measurements) the interaction and self-assembly of the peptide has proven to be very sensitive to the wettability and electro-negativity of the polymeric substrate.The authors acknowledge funding through the European Commission FP7 project RECATABI (NMP3-SL-2009-229239), and from the Spanish Ministerio de Ciencia e Innovacion through projects MAT2011-28791-C03-02 and -03. This work was also supported by the Spanish Ministerio de Educacion through M. Arnal-Pastor FPU 2009-1870 grant. The authors acknowledge the assistance and advice of Electron Microscopy Service of the UPV.Arnal Pastor, MP.; González-Mora, D.; García-Torres, F.; Monleón Pradas, M.; Vallés Lluch, A. (2016). Interaction between acrylic substrates and RAD16-I peptide in its self-assembling. Journal of Polymer Research. 23(9):173-184. https://doi.org/10.1007/s10965-016-1069-3S173184239Davis ME, Motion JP, Narmoneva DA, Takahashi T, Hakuno D, Kamm RD, Zhang S, Lee RT (2005) Injectable self-assembling peptide nanofibers create intramyocardial microenvironments for endothelial cells. Circulation 111(4):442–450Zhang S, Lockshin C, Cook R, Rich A (1994) Unusually stable beta-sheet formation in an ionic self-complementary oligopeptide. Biopolymers 34:663–672Zhang S, Altman M (1999) Peptide self-assembly in functional polymer science and engineering. Reac Func Polym 41:91–102Zhang S, Gelain F, Zhao X (2005) Designer self-assembling peptide nanofiber scaffolds for 3D tissue cell cultures. Semin Cancer Biol 15(5):413–420Zhang S, Zhao X, Spirio L, PuraMatrix (2005) Self-assembling peptide nanofiber scaffolds. In: Ma PX, Elisseeff J (eds) Scaffolding in tissue Engineering. CRC Press, Boca Raton, FL, pp. 217–238Sieminski AL, Semino CE, Gong H, Kamm RD (2008) Primary sequence of ionic self-assembling peptide gels affects endothelial cell adhesion and capillary morphogenesis. J Biomed Mater Res A 87(2):494–504Quintana L, Fernández Muiños T, Genove E, Del Mar Olmos M, Borrós S, Semino CE (2009) Early tissue patterning recreated by mouse embryonic fibroblasts in a three-dimensional environment. Tissue Eng Part A 15(1):45–54Garreta E, Genové E, Borrós S, Semino CE (2006) Osteogenic differentiation of mouse embryonic stem cells and mouse embryonic fibroblasts in a three-dimensional self-assembling peptide scaffold. Tissue Eng 12(8):2215–2227Semino CE, Merok JR, Crane GG, Panagiotakos G, Zhang S (2003) Functional differentiation of hepatocyte-like spheroid structures from putative liver progenitor cells in three-dimensional peptide scaffolds. Differentiation 71:262–270Thonhoff JR, Lou DI, Jordan PM, Zhao X, Compatibility WP (2008) Of human fetal neural stem cells with hydrogel biomaterials in vitro. Brain Res 1187:42–51Tokunaga M, Liu ML, Nagai T, Iwanaga K, Matsuura K, Takahashi T, Kanda M, Kondo N, Wang P, Naito AT, Komuro I (2010) Implantation of cardiac progenitor cells using self-assembling peptide improves cardiac function after myocardial infarction. J Mol Cell Cardiol 49(6):972–983Takei J (2006) 3-Dimensional cell culture scaffold for everyone: drug screening. Tissue engineering and cancer biology. AATEX 11(3):170–176McGrath AM, Novikova LN, Novikov LN, Wiberg MBD (2010) ™ PuraMatrix™ peptide hydrogel seeded with Schwann cells for peripheral nerve regeneration. Brain Res Bull 83(5):207–213Wang W, Itoh S, Matsuda A, Aizawa T, Demura M, Ichinose S, Shinomiya K, Tanaka J (2008) Enhanced nerve regeneration through a bilayered chitosan tube: The effect ofintroduction of glycine spacer into the CYIGSR sequence. J Biomed Mater Res Part A 85:919–928Sargeant TD, Guler MO, Oppenheimer SM, Mata A, Satcher RL, Dunand DC, Stupp SI (2008) Hybrid bone implants: self-assembly of peptide amphiphile nanofibers within porous titanium. Biomaterials 29(2):161–171Vallés-Lluch A, Arnal-Pastor M, Martínez-Ramos C, Vilariño-Feltrer G, Vikingsson L, Castells-Sala C, Semino CE, Monleón Pradas M (2013) Combining self-assembling peptide gels with three-dimensional elastomer scaffolds. Acta Biomater 9(12):9451–9460Valles-Lluch A, Arnal-Pastor M, Martinez-Ramos C, Vilarino-Feltrer G, Vikingsson L, Monleon Pradas M (2013) Grid polymeric scaffolds with polypeptide gel filling as patches for infarcted tissue regeneration. Conf Proc IEEE Eng Med Biol Soc 2013:6961–6964Soler-Botija C, Bagó JR, Llucià-Valldeperas A, Vallés-Lluch A, Castells-Sala C, Martínez-Ramos C, Fernández-Muiños T, Chachques JC, Monleón Pradas M, Semino CE, Bayes-Genis A (2014) Engineered 3D bioimplants using elastomeric scaffold, self-assembling peptide hydrogel, and adipose tissue-derived progenitor cells for cardiac regeneration. Am J Transl Res 6(3):291–301Martínez-Ramos M, Arnal-Pastor M, Vallés-Lluch A, Monleón Pradas M (2015) Peptide gel in a scaffold as a composite matrix for endothelial cells. J Biomed Mater Res Part A 103 A:3293–3302Rico P, Rodríguez Hernández JC, Moratal D, Altankov G, Monleón Pradas M, Salmerón-Sánchez M (2009) Substrate-induced assembly of fibronectin into networks: influence of surface chemistry and effect on osteoblast adhesion. Tissue Eng Part A 15(11):3271–3281Gugutkov D, Altankov G, Rodríguez Hernández JC, Monleón Pradas M, Salmerón Sánchez M (2010) Fibronectin activity on substrates with controlled -OH density. J Biomed Mater Res A 92(1):322–331Rodríguez Hernández JC, Salmerón Sánchez M, Soria JM, Gómez Ribelles JL, Monleón Pradas M (2007) Substrate chemistry-dependent conformations of single laminin molecules on polymer surfaces are revealed by the phase signal of atomic force microscopy. Biophys J 93(1):202–207Cantini M, Rico P, Moratal D, Salmerón-Sánchez M (2012) Controlled wettability, same chemistry: biological activity of plasma-polymerized coatings. Soft Matter 8:5575–5584Anselme K, Ponche A, Bigerelle M (2010) Relative influence of surface topography and surface chemistry on cell response to bone implant materials. Part 2: biological aspects. Proc Inst Mech Eng H J Eng Med 224:1487–1507Hartgerink JD, Beniash E, Stupp SI (2002) Peptide-amphiphile nanofibers: a versatile scaffold for the preparation of self-assembling materials. Proc Natl Acad Sci U S A 99(8):5133–5138Busscher HJ, Vanpelt AWJ, Deboer P, Dejong HP, Arends J (1984) The effect of surface roughening of polymers on measured contact angles of liquids. Colloids Surf 9:319–331Birdi, KS. (1997) Surface tension of polymers. In: Yildrim Erbil H, ed. Handbook of surface and colloid chemistry CRC Press, Boca Raton, p. 292.Collier JH (2003) MessersmithPB.Enzymatic modification of self-assembled peptide structures with tissue transglutaminase. Bioconjug Chem 14(4):748–755Kakiuchi Y, Hirohashi N, Murakami-Murofushi K (2013) The macroscopic structure of RADA16 peptide hydrogel stimulates monocyte/macrophage differentiation in HL60 cells via cholesterol synthesis. BiochemBiophys Res Commun 433(3):298–304Pérez-Garnes M, González-García C, Moratal D, Rico P, Salmerón-Sánchez M (2011) Fibronectin distribution on demixednanoscale topographies. Int J Artif Organs 34(1):54–63Salmerón-Sánchez M, Rico P, Moratal D, Lee TT, Schwarzbauer JE, García AJ (2011) Role of material-driven fibronectin fibrillogenesis in cell differentiation. Biomaterials 32(8):2099–2105Ye Z, Zhang H, Luo H, Wang S, Zhou Q, DU X, et al. (2008) Temperature and pH effects on biophysical and morphological properties of self-assembling peptide RADA16-I. J Pept Sci 14:152–162Keselowsky BG, Collard DM, García AJ (2004) Surface chemistry modulates focal adhesion composition and signaling through changes in integrin binding. Biomaterials 25:5947–5954Scotchford CA, Gilmore CP, Cooper E, Leggett GJ, Downes S (2002) Protein adsorption and human osteoblast-like cell attachment and growth on alkylthiol on gold self-assembled monolayers. J Biomed Mater Res 59:84–99Coelho NM, González-García C, Planell JA, Salmerón-Sánchez M, Altankov G (2010) Different assembly of type IV collagen on hydrophilic and hydrophobic substrata alters endothelial cells interaction. Eur Cell Mater 19:262–272Briz N, Antolinos-Turpin CM, Alió J, Garagorri N, Gómez Ribelles JL, Gómez-Tejedor JA (2013) Fibronectin fixation on poly(ethyl acrylate)-based copolymers. J Biomed Mater Res B Appl Biomater 101(6):991–997Owens DK, Wendt RC (1969) Estimation of the surface free energy of polymers. J Appl Polym Sci 13(8):1741–1747Soria JM, Martínez Ramos C, Bahamonde O, García Cruz DM, Salmerón Sánchez M, García Esparza MA, Casas C, Guzmán M, Navarro X, Gómez Ribelles JL, García Verdugo JM, Monleón Pradas M, Barcia JA (2007) Influence of the substrate's hydrophilicity on the in vitro Schwann cells viability. J Biomed Mater Res A 83(2):463–470Van Krevelen, DW. (1997) Properties of polymers. Chapter 13 mechanical properties of solid polymers. Elsevier, pp. 367–43

The interplay of matrix metalloproteinase-8, transforming growth factor-beta 1 and vascular endothelial growth factor-C cooperatively contributes to the aggressiveness of oral tongue squamous cell carcinoma

Background: Matrix metalloproteinase-8 (MMP-8) has oncosuppressive properties in various cancers. We attempted to assess MMP-8 function in oral tongue squamous cell carcinoma (OTSCC). Methods: MMP-8 overexpressing OTSCC cells were used to study the effect of MMP-8 on proliferation, apoptosis, migration, invasion and gene and protein expression. Moreover, MMP-8 functions were assessed in the orthotopic mouse tongue cancer model and by immunohistochemistry in patient samples. Results: MMP-8 reduced the invasion and migration of OTSCC cells and decreased the expression of MMP-1, cathepsin-K and vascular endothelial growth factor-C (VEGF-C). VEGF-C was induced by transforming growth factor-beta 1 (TGF-beta 1) in control cells, but not in MMP-8 overexpressing cells. In human OTSCC samples, low MMP-8 in combination with high VEGF-C was an independent predictor of poor cancer-specific survival. TGF-beta 1 treatment also restored the migration of MMP-8 overexpressing cells to the level of control cells. In mouse tongue cancer, MMP-8 did not inhibit metastasis, possibly because it was eliminated in the peripheral carcinoma cells. Conclusions: The suppressive effects of MMP-8 in OTSCC may be mediated through interference of TGF-beta 1 and VEGF-C function and altered proteinase expression. Together, low MMP-8 and high VEGF-C expression have strong independent prognostic value in OTSCC.Peer reviewe

New materials and devices for preventing catheter-related infections

Catheters are the leading source of bloodstream infections for patients in the intensive care unit (ICU). Comprehensive unit-based programs have proven to be effective in decreasing catheter-related bloodstream infections (CR-BSIs). ICU rates of CR-BSI higher than 2 per 1,000 catheter-days are no longer acceptable. The locally adapted list of preventive measures should include skin antisepsis with an alcoholic preparation, maximal barrier precautions, a strict catheter maintenance policy, and removal of unnecessary catheters. The development of new technologies capable of further decreasing the now low CR-BSI rate is a major challenge. Recently, new materials that decrease the risk of skin-to-vein bacterial migration, such as new antiseptic dressings, were extensively tested. Antimicrobial-coated catheters can prevent CR-BSI but have a theoretical risk of selecting resistant bacteria. An antimicrobial or antiseptic lock may prevent bacterial migration from the hub to the bloodstream. This review discusses the available knowledge about these new technologies

The Relative Role of Perceived Partner Risks in Promoting Condom Use in a Three-City Sample of High-Risk, Low-Income Women

We examined the effect of women’s perceptions of sexual partner risks on condom use. Women from three US cities (n = 1,967) were recruited to provide data on HIV risks. In univariate models, increased odds of condom use were associated with perceiving that partners had concurrent partners and being unaware of partners': (a) HIV status, (b) bisexuality, (c) concurrency; and/or (d) injection drug use. In multivariate models, neither being unaware of the four partner risk factors nor perceiving a partner as being high risk was associated with condom use. Contextual factors associated with decreased odds of condom use were having sex with a main partner, homelessness in the past year, alcohol use during sex, and crack use in the past 30 days. Awareness of a partner’s risks may not be sufficient for increasing condom use. Contextual factors, sex with a main partner in particular, decrease condom use despite awareness of partner risk factors