79 research outputs found
RNA-Seq Reveals an Integrated Immune Response in Nucleated Erythrocytes
Background: Throughout the primary literature and within textbooks, the erythrocyte has been tacitly accepted to have maintained a unique physiological role; namely gas transport and exchange. In non-mammalian vertebrates, nucleated erythrocytes are present in circulation throughout the life cycle and a fragmented series of observations in mammals support a potential role in non-respiratory biological processes. We hypothesised that nucleated erythrocytes could actively participate via ligand-induced transcriptional re-programming in the immune response. Methodology/Principal Findings: Nucleated erythrocytes from both fish and birds express and regulate specific pattern recognition receptor (PRR) mRNAs and, thus, are capable of specific pathogen associated molecular pattern (PAMP) detection that is central to the innate immune response. In vitro challenge with diverse PAMPs led to de novo specific mRNA synthesis of both receptors and response factors including interferon-alpha (IFNα) that exhibit a stimulus-specific polysomal shift supporting active translation. RNA-Seq analysis of the PAMP (Poly (I:C), polyinosinic:polycytidylic acid)-erythrocyte response uncovered diverse cohorts of differentially expressed mRNA transcripts related to multiple physiological systems including the endocrine, reproductive and immune. Moreover, erythrocyte-derived conditioned mediums induced a type-1 interferon response in macrophages thus supporting an integrative role for the erythrocytes in the immune response. Conclusions/Significance: We demonstrate that nucleated erythrocytes in non-mammalian vertebrates spanning significant phylogenetic distance participate in the immune response. RNA-Seq studies highlight a mRNA repertoire that suggests a previously unrecognized integrative role for the erythrocytes in other physiological systems
Imidazolium-based titanosilicate nanospheres as active catalysts in carbon dioxide conversion:Towards a cascade reaction from alkenes to cyclic carbonates
Porous silica-based nanospheres bearing titanium centres as single site were successfully synthesized employing a time- and energy-efficient procedure. The influence of the post-synthesis treatment on the insertion of Ti was investigated via DR UV-Vis and XPS spectroscopy and the titanium content was quantified through ICP-OES analysis. The textural and structural properties of the different solids were evaluated via XRD, TEM and N2 physisorption. The resulting materials were thereafter covalently functionalized with imidazolium chloride, followed by characterization via 29Si and 13C solid-state NMR, N2 physisorption and chemical combustion analysis. The bi-functional catalysts were tested in the challenging conversion of CO2 with cyclohexene oxide to the corresponding cyclic carbonate as well as with various other epoxides with excellent results. The insertion of Ti as single site played a key role substantially improving the activity of the solids. The most active bi-functional material was successfully recovered and reused through multiple cycle without loss of the catalytic activity. Moreover, the cyclohexene epoxidation reaction was tested as well employing the mono-functionalized Ti-based material. The catalytic mixture, composed by the mono-functional and bi-functional solids, was efficiently used to convert the cyclohexene into cyclohexene oxide and subsequently the cyclohexene oxide into the corresponding carbonate thus opening the prospect for a cascade reaction
River Restoration in Spain: Theoretical and Practical Approach in the Context of the European Water Framework Directive.
River restoration is becoming a priority in many countries because of increasing the awareness of environmental degradation. In Europe, the EU Water Framework Directive (WFD) has significantly reinforced river restoration, encouraging the improvement of ecological status for water bodies. To fulfill the WFD requirements, the Spanish Ministry of the Environment developed in 2006 a National Strategy for River Restoration whose design and implementation are described in this paper. At the same time many restoration projects have been conducted, and sixty of them have been evaluated in terms of stated objectives and pressures and implemented restoration measures. Riparian vegetation enhancement, weir removal and fish passes were the most frequently implemented restoration measures, although the greatest pressures came from hydrologic alteration caused by flow regulation for irrigation purposes. Water deficits in quantity and quality associated with uncontrolled water demands seriously affect Mediterranean rivers and represent the main constraint to achieving good ecological status of Spanish rivers, most of them intensively regulated. Proper environmental allocation of in-stream flows would need deep restrictions in agricultural water use which seem to be of very difficult social acceptance. This situation highlights the need to integrate land-use and rural development policies with water resources and river management, and identifies additional difficulties in achieving the WFD objectives and good ecological status of rivers in Mediterranean countries
Family businesses from emerging markets and choice of entry mode abroad: insights from Indian firms
Internationalization of family businesses (FBs) is an interesting topic that has received extensive attention in the literature during the last decades. Prior studies emphasized the conservative attitude toward risk of FBs. However, studies addressing international decisions of emerging-market FBs (EMFBs) are still scarce. We investigate whether home and host countries matter when EMFBs choose the entry mode abroad. By doing so, we discern whether they follow the same behavioral pattern as developed-country multinational enterprises (MNEs) or they show a distinctive strategic behavior. Drawing on a sample of 298 foreign market entries carried out by Indian MNEs, our results show that Indian FBs prefer acquisitions instead of greenfield investments. Moreover, host country factors matter, since outward foreign direct investment (OFDI) of Indian FBs in developed markets is associated with a preference for acquisitions, whereas OFDI in developing countries is associated with greenfield investments
Entry Mode Degree of Control, Firm Performance and Host Country Institutional Development: A Meta-Analysis
Among studies on performance outcomes of entry mode choices disagreement fueled by ambiguous research findings is apparent as regards whether the best per- formers are those firms that enter foreign countries with high or low entry mode degree of control. To solve this dilemma and test new hypotheses, the relationship between entry mode degree of control and firm performance is examined by meta- analyzing 133 studies (740,114 observations) covering entry mode choices from 1980 to 2010. We find that (a) overall high-control entry modes lead to higher per- formance, and (b) adopting high-control entry modes is particularly important for firms entering developing countries
PSS18 ECONOMIC EVALUATION OF A 100% WHEY-BASED, PARTIALLY HYDROLYZED INFANT FORMULA IN THE PREVENTION OF ATOPIC DERMATITIS AMONG SPANISH CHILDREN
Chiral S,S-donor ligands in palladium-catalysed allylic alkylation
Chiral dithioether ligands have been tested in the model Pd-catalysed allylic alkylation reaction of (+/-)-3-acetoxy-1,3-diphenyl-1-propene with dimethyl malonate. giving high enantioselectivity (up to 81% e.e.) for the first time in this type of system. Pd(Il)-allylic intermediates, [Pd(eta (3)-1,3-Ph-2-C3H3)(dithioether)]PF6 were prepared and characterised both in solution by NMR spectroscopy and solid state. The X-ray structure for [Pd(eta (3)-1,3-Ph-2-C3H3)(L)]PF6 (L=(R,R)-7,8-O-isopropylidene-1,5-dithiacyclononane) was determined. (C) 2001 Elsevier Science Ltd. All rights reserved
Allylic alkylations catalyzed by palladium systems containing modular chiral dithioethers. A structural study of the allylic intermediates
Palladium allylic systems containing modular chiral dithioether ligands were chosen as catalysts for a systematic study of homodonor ligands in allylic alkylation reactions. For this purpose, new type-DMPS (4-6) and -DEGUS (8, 9) ligands were synthesized. Dithioethers 4-6 afforded high activities and excellent selectivities in all Pd-catalyzed allylic reactions. Particularly the Pd/6 catalytic system provided b-VIII with an ee > 99% and a regioselectivity 1/b (VIII) = 1/1.6. A family of intermediate complexes containing several allyl groups (symmetrical, 13-16 and 20, and nonsymmetrical, 17-19, moieties) and dithioether ligands (4-6, 8, 9, 11, and 12) is described. The complexes were fully characterized both in solution and in the solid state. X-ray structures of four of these complexes (16-18 and 20) were determined. The diastereomers present in solution were studied by NMR spectroscopy, and in some cases it was possible to establish a relationship between the diastereomeric excesses and the selectivities found in the catalytic process
Molecularly imprinted polymers with synthetic dummy templates for the preparation of capsaicin and dihydrocapsaicin from chili peppers
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