300 research outputs found
Detection of RHDV strains in the Iberian hare (Lepus granatensis): earliest evidence of rabbit lagovirus cross-species infection
This is an Open Access article distributed under the terms of the Creative Commons Attribution License.-- et al.Rabbit hemorrhagic disease virus (RHDV) is a highly lethal Lagovirus, family Caliciviridae, that threatens European rabbits (Oryctolagus cuniculus). Although a related virus severely affects hares, cross-species infection was only recently described for new variant RHDV in Cape hares (Lepus capensis mediterraneus). We sequenced two strains from dead Iberian hares (Lepus granatensis) collected in the 1990s in Portugal. Clinical signs were compatible with a Lagovirus infection. Phylogenetic analysis of the complete capsid gene positioned them in the RHDV genogroup that circulated on the Iberian Peninsula at that time. This is the earliest evidence of RHDV affecting a species other than European rabbits.This work was supported by FCT (Fundação para a CiĂȘncia e a Tecnologia; research project ref.: FCT-ANR/BIABIC/0043/2012). FCT also supported the doctoral grants of AML and AP (refs.: SFRH/BD/78738/2011 and SFRH/BD/71252/2010) and the FCT Investigator grant of JA (ref.: IF/01396/2013). âGenomics Applied To Genetic Resourcesâ co-financed by North Portugal Regional Operational Programme 2007/2013
(ON.2 â O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF), also supported this work.Peer Reviewe
Synthesis of heterocyclic compounds by radical electrochemical approach in environmentally friendly media
Radical cyclisation is rapidly becoming an important method for the formation of cyclic systems. Hence, some electrochemical results obtained in the study of electroreductive intramolecular cyclisation of ethyl 2-bromo-3-(3,4-methylenedioxophenyl)-3-(propargyloxy)propanoate (1a), [1-bromo-2-methoxy-2-(prop-2â-ynyloxy) ethyl] benzene (1b) and 1-[2-bromo-2-phenyl-1-(prop-2â-ynyloxy)ethyl]-4-methoxybenzene (1c) promoted by (1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetra-decane)nickel(I), [Ni(tmc)]+, electrogenerated at glassy carbon cathodes in ethanol, ethanol / water and microemulsions made with cationic and anionic surfactants are presented. The results obtained indicate that the reaction proceeds via cleavage of the carbonâbromine bond to form a radical intermediate that undergoes cyclization on the unsaturated C-C bond to afford the substituted tetrahydrofurans.Fundação para a CiĂȘncia e a Tecnologia (FCT
New adsorbers for the removal of genotoxic impurities from active pharmaceutical ingredients
Active pharmaceutical ingredients (APIs) available in the market are mostly synthesized, in organic solvent media, using highly reactive molecules that may be present in the final product as genotoxic impurities (GTIs). These compounds have the ability to react with DNA, preventing its normal replication, resulting in an associated carcinogenic risk, becoming an increasing concern from pharmaceutical companies and regulatory authorities [1]. Although it is desirable to avoid the use of GTIs in the manufacture of APIs, this is not always possible. Therefore, there is a call to develop simple, robust and economical routes to remove GTIs to limits below the Threshold of Toxicological Concern (1.5 ”g/day) [2]. Such adsorbents should be highly selective to reach ultra-low GTI levels with minimal API losses and compatible with organic solvents where the API synthesis takes place [3].
Herein we report two different strategies for the development of new adsorbing materials designed for selective removal of GTIs from API organic solvent solutions. These new materials are: i) molecular imprinted polymers (MIPs), in the particular case designed for removal of an aromatic amine GTI, 4-dymethylaminopyridine) [4]; and ii) a novel functionalized polymer consisting on polybenzimidazole (PBI) modified with a DNA base (PBI-adenine). PBI-Adenine is designed to have a high affinity for a broad range of DNA alkylating agents mimicking the DNA-GTI adduct formation that takes place in vivo [5,6]. These platforms proved to be robust materials being able to remove, in a single stage, more than 95% of the GTIs from organic solvent API mixtures. Both approaches, meet the pharmaceutical industry challenges, by opening new horizons for the use of these adsorbers as a complement to the existing operation units as MIPs, as well as their assembling as membranes for organic solvent nanofiltration (OSN) derived from PBI.
References
[1] Teasdale A. et al., Org. Process Res. Dev. 17, 2013, 221-230.
[2] EMEA Guidelines on the âLimits on Genotoxic Impuritiesâ, EMEA/CHMP/QWP/251344/2006, 2006.
[3] Székely G. et al., Green Chem. 15, 2013, 210-225.
[4] Esteves T. et al., Sep. Purif. Technol. 163, 2016, 206-214.
[5] Ferreira F. C.; Esteves T.; Vicente A. I.; Afonso C. A. M., âPolĂmeros polibenzimidazolo com cadeia espaçadora funcionalizada e seu mĂ©todo de obtenção para remoção de impurezas genotĂłxicas.â Patent request NÂș 109480, with priority date of 22 June 2016.
[6] Vicente A. I. et al., Chem. Mat., 2016, under preparation.
Acknowledgements: We thank financial support from Fundação para a CiĂȘncia e Tecnologia (FCT) through the Project SelectHost (PTDC/QEQ-PRS/4157/2014) and iBB-Institute for Bioengineering and Biosciences (UID/BIO/04565/2013), from Programa Operacional Regional de Lisboa 2020 (Lisboa-01-0145-FEDER-007317). We thank to Hovione PharmaScience Ltd for supplying the API and technical know-how
Reductive intramolecular cyclization of D-glucose-based unsaturated substrates by indirect electrochemical approach in âGreenâ media
Radical cyclisation continues to be a central methodology for the preparation of natural products containing heterocyclic rings.
Hence, some electrochemical results obtained by cyclic voltammetry and controlled-potential electrolysis in the study of electroreductive intramolecular cyclisation of ethyl (2S, 3R)-2-
bromo-3-propargyloxy-3-(2â,3â,4â,6â-tetra-O-acetyl-ÎČ-D-glucopyranosiloxy) propanoate (1) promoted by (1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetra-decane)nickel(I), [Ni(tmc)]+,
electrogenerated at glassy carbon cathodes in ethanol and ethanol/water mixtures containing tetraalkylammonium salts, are
presented.
During controlled-potential electrolyses of solutions containing [Ni(tmc)]2+ and acetylated D-glucose-based bromo propargyl ester (1) catalytic reduction of the latter proceeds via one-electron cleavage of the carbonâbromine bond to form a radical
intermediate that undergoes cyclization to afford the substituted tetrahydrofurans.Fundação para a CiĂȘncia e a Tecnologia (FCT
Neptunomyces aureus gen. et sp. nov. (Didymosphaeriaceae, Pleosporales) isolated from algae in Ria de Aveiro, Portugal
A collection of fungi was isolated from macroalgae of the genera Gracilaria, Enteromorpha and Ulva in the estuary Ria de Aveiro in Portugal. These isolates were characterized through a multilocus phylogeny based on ITS region of the ribosomal DNA, beta-tubulin (tub2) and translation elongation factor 1 alpha (tef1-a) sequences, in conjunction with morphological and physiological data. These analyses showed that the isolates represented an unknown fungus for which a new genus, Neptunomyces gen. nov. and a new species, Neptunomyces aureus sp. nov. are proposed. Phylogenetic analyses supported the affiliation of this new taxon to the family Didymosphaeriaceae. Copyright Micael F.M. Gonçalves et al.info:eu-repo/semantics/publishedVersio
Reactions radicalaires dans des milieux protiques et aprotiques : comparaisons entre les cyclisations reductives electrochimiques catalysees par des complexes du nickel
The electrochemical reductive cyclisation of unsaturated organic halides in the presence of Ni(II) complexes as catalysts was
examined in aprotic solvents such as DMF and in protic solvents such as ethanol, butanol or ethanolewater mixtures. The presence
of the alcohol media enhanced the rate of recycling of the catalytic species.La cyclisation rĂ©ductive Ă©lectrochimique dâhalogĂ©nures insaturĂ©s en prĂ©sence de complexes de Ni(II) comme catalyseurs a Ă©tĂ© examinĂ©e dans des solvants comme le DMF et dans des solvants protiques comme lâĂ©thanol, le butanol ou des mĂ©langes Ă©thanol-eau. La prĂ©sence du milieu alcoolique augmente la vitesse du recyclage des espĂšces catalytiques.Fundação para a CiĂȘncia e a Tecnologia (FCT
Impact of the Cationic Moiety of Ionic Liquids on Chemoselective Artificial Olfaction
Funding Information: This research was funded by the European Research Council (ERC) under the EU Horizon 2020 research and innovation program [grant reference SCENT-ERC-2014-STG-639123, 2015â2022, and Grant Agreement No. 101069405âENSUREâERC-2022-POC1] and by national funds from FCT-Fundação para a CiĂȘncia e a Tecnologia, I.P., for projects PTDC/BII-BIO/28878/2017, PTDC/CTM-CTM/3389/2021, UIDP/04378/2020, and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences-UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy-i4HB. The authors thank FCT/MCTES for the PhD grant SFRH/BD/128687/2017. Publisher Copyright: © 2023 The Authors. Published by American Chemical Society.Ionogels and derived materials are assemblies of polymers and ionic liquids characterized by high stability and ionic conductivity, making them interesting choices as gas sensors. In this work, we assessed the effect of the ionic liquid moiety to generate ionogels and hybrid gels as electrical and optical gas sensors. Six ionic liquids consisting of a constant anion (chloride) and distinct cationic head groups were used to generate ionogels and hybrid gels and further tested as gas sensors in customized electronic nose devices. In general, ionogel-based sensors yielded higher classification accuracies of standard volatile organic compounds when compared to hybrid material-based sensors. In addition, the high chemical diversity of ionic liquids is further translated to a high functional diversity in analyte molecular recognition and sensing.publishersversionpublishe
Insights into the restoration of tributyltin contaminated environments using marine bacteria from Portuguese fishing ports
Tributyltin (TBT) is an organotin chemical mainly used as biocide in marine antifouling paints. Despite the restrictions and prohibitions on its use, TBT is still an environmental problem due to its extensive application and subsequent release into the environment, being regarded as one of the most toxic chemicals released into the marine ecosystems. Microorganisms inhabiting impacted sites are crucial for their restoration since they have developed mechanisms to tolerate and break down pollutants. Nonetheless, transformation products resulting from the degradation process may still be toxic or, sometimes, even more toxic than the parent compound. The determination of the parent and degradation products by analytical methods, although necessary, may not be ecologically relevant since no information is provided regarding their ecotoxicity. In this study, marine bacteria collected from seven Portuguese fishing ports were isolated and grown in the presence of TBT. Bacteria that exhibited higher growth were used to bioremediate TBT-contaminated waters. The potential of these bacteria as bioremediation agents was evaluated through ecotoxicological assays using the sea snail Gibbula umbilicalis as model organism. Data suggested that some TBT-tolerant bacteria, such as Pseudomonas putida, can reduce the toxicity of TBT contaminated environments. This work contributes to the knowledge of TBT-degrading bacteria.info:eu-repo/semantics/publishedVersio
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