A revision of the Peruvian species of Nasa ser. Alatae (Loasaceae)

The Nasa series Alatae is revised for Peru. Species limits in this group are re-investigated on the basis of modern collections, all types and extensive field studies. A total of 12 species are recognized, seven of them- N. dillonii, N. driesslet, N. nubicolorum, N. pascoensis, N. sagasteguii, N, anderssonii and N. urentivelutina -are described as new to science. All new, and two of the previously recognized species are illustrated by line drawings. The species of this group are from Andean habitats, mostly cloud forests, and nearly all of them are narrow endemics.     

The Physics of Small Molecule Acceptors for Efficient and Stable Bulk Heterojunction Solar Cells

Organic bulk heterojunction solar cells based on small molecule acceptors have recently seen a rapid rise in the power conversion efficiency with values exceeding 13%. This impressive achievement has been obtained by simultaneous reduction of voltage and charge recombination losses within this class of materials as compared to fullerene‐based solar cells. In this contribution, the authors review the current understanding of the relevant photophysical processes in highly efficient nonfullerene acceptor (NFA) small molecules. Charge generation, recombination, and charge transport is discussed in comparison to fullerene‐based composites. Finally, the authors review the superior light and thermal stability of nonfullerene small molecule acceptor based solar cells, and highlight the importance of NFA‐based composites that enable devices without early performance loss, thus resembling so‐called burn‐in free devices.     

The geometry of gender: hyper‐diversification of sexual systems in Urtica L. (Urticaceae)

Urtica L. (Urticaceae) is generally reported as a genus of monoecious and dioecious taxa. However, the gender information found in the literature does not at all reflect the actual diversity of gender patterns in Urtica. Dioecy appears to be truly absent from Urtica, but otherwise there has been a major diversification in the geometry of gender and no comparable patterns exist in other plant groups. Thus, we here define technical terms for all unique architectural types of monoecy found in Urtica and closely related genera and reconstruct the ancestral gender states in a Bayesian framework. Our studies are based on a near‐comprehensive sampling, including 61 of the 63 Urtica species recognized. We report polygamy, two types of gynodioecy and five different architectural types of monoecy. A total of 15 switches appear to have taken place within the genus. Although gender characteristics have diversified strongly, they are relatively conserved within clades. Monoecy is the predominant sexual system within Urtica and specifically basiandrous monoecy (i.e. basal inflorescence branches of each individual male only, apical branches female) is the most widespread type, reported for 11 different clades. In particular, it characterizes the basally branching pilulifera‐clade and the sister genus Zhengyia, and may thus represent the plesiomorphic condition for Urtica. Gender distribution and gross morphology appear to evolve largely independently from each other and gender distribution is largely independent of growth habit. However, polygamous taxa are most common amongst rhizomatous perennials (one‐third of the taxa).     

Structural and Functional Studies on the Interaction of Adenovirus Fiber Knobs and Desmoglein 2

Human adenovirus (Ad) serotypes Ad3, Ad7, Ad11, and Ad14, as well as a recently emerged strain of Ad14 (Ad14p1), use the epithelial junction protein desmoglein 2 (DSG2) as a receptor for infection. Unlike Ad interaction with CAR and CD46, structural details for Ad binding to DSG2 are still elusive. Using an approach based on Escherichia coli expression libraries of random Ad3 and Ad14p1 fiber knob mutants, we identified amino acid residues that, when mutated individually, ablated or reduced Ad knob binding to DSG2. These residues formed three clusters inside one groove at the extreme distal end of the fiber knob. The Ad3 fiber knob mutant library was also used to identify variants with increased affinity to DSG2. We found a number of mutations within or near the EF loop of the Ad3 knob that resulted in affinities to DSG2 that were several orders of magnitude higher than those to the wild-type Ad3 knob. Crystal structure analysis of one of the mutants showed that the introduced mutations make the EF loop more flexible, which might facilitate the interaction with DSG2. Our findings have practical relevance for cancer therapy. We have recently reported that an Ad3 fiber knob-containing recombinant protein (JO-1) is able to trigger opening of junctions between epithelial cancer cells which, in turn, greatly improved the intratumoral penetration and efficacy of therapeutic agents (I. Beyer, et al., Clin. Cancer Res. 18:3340–3351, 2012; I. Beyer, et al., Cancer Res. 71:7080–7090, 2011). Here, we show that affinity-enhanced versions of JO-1 are therapeutically more potent than the parental protein in a series of cancer models.     

Determination of Glyphosate and AMPA in Three Representative Agricultural Austrian Soils with a HPLC-MS/MS Method

We developed a novel method to quantify adsorbed glyphosate and AMPA in soils based on an extraction utilizing Na-tetraborate, an SPE clean-up step, and subsequent LC-MS detection. Reversed phase-based separation of glyphosate and AMPA was realized after FMOC-derivatization. The quantification involved external calibration and 1,2–¹³C, ¹⁵N- labeled glyphosate as well as ¹³C, ¹⁵N labeled AMPA as internal standards. The optimum recovery for extraction was obtained with 40 mM Na-tetraborate. The method was applied in three representative soils (Kirchberg, Phyra, and Pixendorf, Austria) where glyphosate was applied by standard agricultural practices. The recovery for glyphosate extracted with 40 mM Na-tetraborate buffer was 93.5% (RSD <2%) for glyphosate at Kirchberg-cambisol; 95.7% (RSD < 2%) at Pixendorf- chernozem and 79.1% (RSD <7%) at Phyra-stagnosol. The corresponding values for AMPA were 92.4% (RSD <2%) at Kirchberg, 98.1% (RSD <2%) at Pixendorf and 69.9% (RSD <4%) at Phyra. The limits of detection for glyphosate were 6.8 μg kg^?1(RSD <10%) at Kirchberg, 4.3 μg kg^?1 (RSD <10%) at Pixendorf, and 46.5 μg kg^?1 (RSD <7%) at Phyra. The limits of detection for AMPA were 26.7 μg kg^?1 (RSD <10%) at Kirchberg, 25.2 μg kg^?1 (RSD <10%) at Pixendorf, and 120.3 μg kg^?1 (RSD <9%) at Phyra. Accordingly, the limits of quantification were 22.7 μg kg^?1(RSD <5%) for glyphosate, and 88.9 μg kg^?1 (RSD <2%) for AMPA at Kirchberg and respectively 14.4 μg kg^?1 (RSD <6%) and 84 μg kg^?1 (RSD <5%) at Pixendorf and 13.8 μg kg^?1 (RSD <6%) and 87.2 μg kg^?1 (RSD <8%) at Phyra. Both substances in the soils were lower than the LOQ before applying the herbicide Roundup. The influence of higher contents of iron oxides, clay, and acidic pH, resulting in a more pronounced adsorption of glyphosate and AMPA in the soils of Phyra and Kirchberg, is demonstrated.     

Fabricating High Performance,Donor–Acceptor Copolymer Solar Cells by Spray‐Coating in Air

We report the fabrication of high performance organic solar cells by spray‐coating the photoactive layer in air. The photovoltaic blends consist of a blend of carbazole and benzothiadiazole based donor–acceptor copolymers and the fullerene derivative PC₇₀BM. Here, we formulate a number of photovoltaic inks using a range of solvent systems that we show can all be deposited by spray casting. We use a range of techniques to characterize the structure of such films, and show that spray‐cast films have comparable surface roughness to spin‐cast films and that vertical stratification that occurs during film drying reduces the concentration of PCBM towards the underlying PEDOT:PSS interface. We also show that the active layer thickness and the drying kinetics can be tuned through control of the substrate temperature. High power conversion efficiencies of 4.3%, 4.5% and 4.6% were obtained for solar cells made from a blend of PC₇₀BM with the carbazole‐based co‐polymers PCDTBT, P2 and P1. By applying a low temperature anneal after the deposition of the cathode, the efficiency of spray‐cast solar‐cells based on a P2:PC₇₀BM blend is increased to 5.0%. Spray coating holds significant promise as a technique capable of fabricating large‐area, high performance organic solar cells in air.     

Inhibition of hepatitis B virus replication in cultured cells and in vivo using 2′-O-guanidinopropyl modified siRNAs

Silencing hepatitis B virus (HBV) gene expression with exogenous activators of the RNA interference (RNAi) pathway has shown promise as a new mode of treating infection with the virus. However, optimizing efficacy, specificity, pharmacokinetics and stability of RNAi activators remains a priority before clinical application of this promising therapeutic approach is realised. Chemical modification of synthetic short interfering RNAs (siRNAs) provides the means to address these goals. This study aimed to assess the benefits of incorporating nucleotides with 2′-O-guanidinopropyl (GP) modifications into siRNAs that target HBV. Single GP residues were incorporated at nucleotide positions from 2 to 21 of the antisense strand of a previously characterised effective antiHBV siRNA. When tested in cultured cells, siRNAs with GP moieties at selected positions improved silencing efficacy. Stability of chemically modified siRNAs in 80% serum was moderately improved and better silencing effects were observed without evidence for toxicity or induction of an interferon response. Moreover, partially complementary target sequences were less susceptible to silencing by siRNAs with GP residues located in the seed region. Hydrodynamic co-injection of siRNAs with a replication-competent HBV plasmid resulted in highly effective knock down of markers of viral replication in mice. Evidence for improved efficacy, reduced off target effects and good silencing in vivo indicate that GP-modifications of siRNAs may be used to enhance their therapeutic utility.     

Activation of Olfactory Receptors on Mouse Pulmonary Macrophages Promotes Monocyte Chemotactic Protein-1 Production

Background

Emerging evidence suggests that non-olfactory tissues and cells can express olfactory receptors (ORs), however, the exact function of ectopic OR expression remains unknown. We have previously shown in mouse models that a unique cooperation between interferon-γ (IFN-γ) and lipopolysaccharide (LPS) drives the activation of pulmonary macrophages and leads to the induction of pathogenic responses in the respiratory tract. Further, through gene array studies, we have shown that activation of macrophages by these molecules results in the selective expression of a number of ORs. In this study, we validated the expression of these ORs in mouse airway and pulmonary macrophages in response to IFN-γ and LPS (γ/LPS) stimulation, and further explored the effect of odorant stimulation on macrophage function.

Methodology/Principal Findings

OR expression in airway and pulmonary macrophages in response to IFN-γ, LPS or γ/LPS treatments was assessed by microarray and validated by q-PCR. OR expression (e.g. OR622) on macrophages was confirmed by visualization in immunofluoresence assays. Functional responses to odorants were assessed by quantifying inflammatory cytokine and chemokine expression using q-PCR and cell migration was assessed by a modified Boyden chamber migration assay. Our results demonstrate that eight ORs are expressed at basal levels in both airway and pulmonary macrophages, and that γ/LPS stimulation cooperatively increased this expression. Pulmonary macrophages exposed to the combined treatment of γ/LPS+octanal (an odorant) exhibited a 3-fold increase in MCP-1 protein production, compared to cells treated with γ/LPS alone. Supernatants from γ/LPS+octanal exposed macrophages also increased macrophage migration in vitro.

Conclusions/Significance

Eight different ORs are expressed at basal levels in pulmonary macrophages and expression is upregulated by the synergistic action of γ/LPS. Octanal stimulation further increased MCP-1 production and the motility of macrophages. Our results suggest that ORs may mediate macrophage function by regulating MCP-1 production and cell migration.