21 research outputs found

    Implementing supply chain visibility to promote fisheries sustainability

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    Operationalising good practices and better management of marine resources were pursued, in a retailer exploratory case, by following a triple bottom line approach to fine tuning corporate responsibility. Recommendations towards sustainable operations were made, as regards: developing voluntary self-certification towards eco-labelling based on third party; using IT, as a transparency promoter and so, as a leverage for traceability, collaboration and trust across the chain of custody; designing customised policies to deal with different consumer profiles and so, assuring their loyalty by adjusting consumer campaigns; educating consumers as seafood demand regulators. Improvements in Greenpeace evaluation were documented, profit increase was expected.info:eu-repo/semantics/publishedVersio

    Activation pathway to amino acid adducts

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    Funding: This work was supported in part by Fundação para a Ciência e a Tecnologia (FCT), Portugal (PTDC/QUI-QUI/113910/2009, RECI/QEQ-MED/0330/2012, UID/QUI/00100/2013 and IF/ 01091/2013/CP1163/CT0001), and by Interagency Agreement Y1ES1027 between the National Center for Toxicological Research/Food and Drug Administration and the National Institute of Environmental Health Sciences/National Toxicology Program. The opinions expressed in this paper do not necessarily represent those of the U.S. Food and Drug Administration. RW, ALG, ILM and SGH thank FCT for postdoctoral and doctoral fellowships (SFRH/BPD/70953/2010, SFRH/BD/72301/2010, SFRH/BD/75426/2010 and SFRH/BD/ 80690/2011, respectively). AMM also acknowledges Programa Operacional Potencial Humano from FCT and the European Social Fund (IF/01091/2013), and the LRI Innovative Science Award. We thank the Portuguese NMR and MS networks (IST nodes) for providing access to the facilities.Nevirapine (NVP) is the non-nucleoside HIV-1 reverse transcriptase inhibitor most commonly used in developing countries, both as a component of combined antiretroviral therapy and to prevent mother-to-child transmission of the virus; however, severe hepatotoxicity and serious adverse cutaneous effects raise concerns about its safety. NVP metabolism yields several phenolic derivatives conceivably capable of undergoing further metabolic oxidation to electrophilic quinoid derivatives prone to react with bionucleophiles and initiate toxic responses. We investigated the ability of two phenolic NVP metabolites, 2-hydroxy-NVP and 3-hydroxy-NVP, to undergo oxidation and subsequent reaction with bionucleophiles. Both metabolites yielded the same ring-contraction product upon oxidation with Frémy's salt in aqueous medium. This is consistent with the formation of a 2,3-NVP-quinone intermediate, which upon stabilization by reduction was fully characterized by mass spectrometry and nuclear magnetic resonance spectroscopy. Additionally, we established that the oxidative activation of 2-hydroxy-NVP involved the transient formation of both the quinone and a quinone-imine, whereas 3-hydroxy-NVP was selectively converted into 2,3-NVP-quinone. The oxidations of 2-hydroxy-NVP and 3-hydroxy-NVP in the presence of the model amino acids ethyl valinate (to mimic the highly reactive N-terminal valine of hemoglobin) and N-acetylcysteine were also investigated. Ethyl valinate reacted with both 2,3-NVP-quinone and NVP-quinone-imine, yielding covalent adducts. By contrast, neither 2,3-NVP-quinone nor NVP-derived quinone-imine reacted with N-acetylcysteine. The product profile observed upon Frémy's salt oxidation of 2-hydroxy-NVP in the presence of ethyl valinate was replicated with myeloperoxidase-mediated oxidation. Additionally, tyrosinase-mediated oxidations selectively yielded 2,3-NVP-quinone-derived products, while quinone-imine-derived products were obtained upon lactoperoxidase catalysis. These observations suggest that the metabolic conversion of phenolic NVP metabolites into quinoid electrophiles is biologically plausible. Moreover, the lack of reaction with sulfhydryl groups might hamper the in vivo detoxification of NVP-derived quinone and quinone-imine metabolites via glutathione conjugation. As a result, these metabolites could be available for reaction with nitrogen-based bionucleophiles (e.g., lysine residues of proteins) ultimately eliciting toxic events.publishersversionpublishe

    Differences in Nevirapine Biotransformation as a Factor for its Sex-Dependent Dimorphic Profile of Adverse Drug Reactions

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    OBJECTIVES: Nevirapine is widely used for the treatment of HIV-1 infection; however, its chronic use has been associated with severe liver and skin toxicity. Women are at increased risk for these toxic events, but the reasons for the sex-related differences are unclear. Disparities in the biotransformation of nevirapine and the generation of toxic metabolites between men and women might be the underlying cause. The present work aimed to explore sex differences in nevirapine biotransformation as a potential factor in nevirapine-induced toxicity. METHODS: All included subjects were adults who had been receiving 400 mg of nevirapine once daily for at least 1 month. Blood samples were collected and the levels of nevirapine and its phase I metabolites were quantified by HPLC. Anthropometric and clinical data, and nevirapine metabolite profiles, were assessed for sex-related differences. RESULTS: A total of 52 patients were included (63% were men). Body weight was lower in women (P = 0.028) and female sex was associated with higher alkaline phosphatase (P = 0.036) and lactate dehydrogenase (P = 0.037) levels. The plasma concentrations of nevirapine (P = 0.030) and the metabolite 3-hydroxy-nevirapine (P = 0.035), as well as the proportions of the metabolites 12-hydroxy-nevirapine (P = 0.037) and 3-hydroxy-nevirapine (P = 0.001), were higher in women, when adjusted for body weight. CONCLUSIONS: There was a sex-dependent variation in nevirapine biotransformation, particularly in the generation of the 12-hydroxy-nevirapine and 3-hydroxy-nevirapine metabolites. These data are consistent with the sex-dependent formation of toxic reactive metabolites, which may contribute to the sex-dependent dimorphic profile of nevirapine toxicity

    Plano estratégico: last minute best accommodation

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    O presente trabalho foi desenvolvido e apresentado sob a forma de projeto de negócio. Este projeto visa compreender a conjuntura atual do mercado de trabalho versus o aumento do turismo que se tem vindo a verificar em Portugal. Neste projeto procurou-se analisar o turismo em Portugal e em particular o alojamento disponível em períodos "altos" de férias. Hoje em dia muitos trabalhadores não conseguem reservar um alojamento para férias com antecedência por questões pessoais ou porque na maior partes das vezes o trabalho não permite uma marcação antecipada. Como tal, o projeto visa analisar uma hipótese para assegurar alojamento para férias a este nicho de mercado que por vezes acaba por despender muito dinheiro devido à escassez de produtos e à urgência na aquisição dos mesmos.The following project was developed for a future business project. This paper work has some potential analyses regarding the work experience day to day of the population in Portugal and the tourism indicators that have been growing faster and faster. The focus in this project was to analyze the tourism in general and in particularly the number of accommodations free in “high” periods of the year like July and August that are the months with good weather in Portugal. Nowadays people, who work for other companies and even entrepreneurs, hardly can plan their holidays in advance due the volume of last minute work that comes up. Therefore, this project is focused in analyze and discover a solution to make sure this target gets an accommodation even when they try to book in the "last minute". The intention is to provide accommodation for holidays to people who need a last minute reservation without having to pay an enormous price due to the lack of offer they may have

    Addressing Latent Tuberculosis: New Advances in Mimicking the Disease, Discovering Key Targets, and Designing Hit Compounds

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    Despite being discovered and isolated more than one hundred years ago, tuberculosis (TB) remains a global public health concern arch. Our inability to eradicate this bacillus is strongly related with the growing resistance, low compliance to current drugs, and the capacity of the bacteria to coexist in a state of asymptomatic latency. This last state can be sustained for years or even decades, waiting for a breach in the immune system to become active again. Furthermore, most current therapies are not efficacious against this state, failing to completely clear the infection. Over the years, a series of experimental methods have been developed to mimic the latent state, currently used in drug discovery, both in vitro and in vivo. Most of these methods focus in one specific latency inducing factor, with only a few taking into consideration the complexity of the granuloma and the genomic and proteomic consequences of each physiological factor. A series of targets specifically involved in latency have been studied over the years with promising scaffolds being discovered and explored. Taking in account that solving the latency problem is one of the keys to eradicate the disease, herein we compile current therapies and diagnosis techniques, methods to mimic latency and new targets and compounds in the pipeline of drug discovery

    Synthesis and Characterization of New Organometallic Benzo[b]thiophene Derivatives with Potential Antitumor Properties

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    The incorporation of organometallic moieties into the structure of known active drugs to improve their therapeutic properties has gained considerable interest in recent years. The benzo- [b]thiophene derivative raloxifene is a selective estrogen receptor modulator (SERM) that has been found to decrease breast cancer risk in postmenopausal women compared to placebo. The current data suggest that, in the postmenopausal setting, raloxifene may have the benefits of the widely used tamoxifen with fewer side effects. As part of a program designed toward the synthesis and biological screening of organometallic benzo[b]thiophene derivatives inspired by the structure of raloxifene, we have prepared a series of 2-benzoyl-3-ferrocenylbenzo[b]thiophenes where the benzoyl sub- stituent contains terminal tertiary alkylamino groups, expected to ensure affinity to the estrogen receptor. The synthetic strategy and full characterization (NMR, MS, X-ray diffraction, cyclic voltammetry) of the new ferrocenylbenzo[b]thiophenes is reported herein. Moreover, the new 2- benzoyl-3-ferrocenylbenzo[b]thiophene derivatives were tested for their cytotoxic properties against several human tumor cell lines. All the test compounds showed considerable cytotoxic activity; among these, [3-ferrocenyl-6-methoxybenzo[b]thiophen-2-yl][4-(piperazin-1-yl)methyl- phenyl]methanone (compound 13) is of note, showing IC50 values in the low-micromolar range and more than 1 order of magnitude lower than those of the reference compound, cisplatin. In addition, chemosensitivity tests on resistant phenotypes indicated that compound 13 elicited no cross-resistance with cisplatin, besides not being a potential multidrug-resistant (MDR) substrate. Moreover, caspase-3 activation analyses revealed that 13 induced a caspase-3-dependent apoptotic cell-death mechanism. Taken together, these data suggest that the new 2-benzoyl-3- ferrocenylbenzo[b]thiophenes, in particular compound 13, have potentially useful antitumor properties

    Covalent histone modification by an electrophilic derivative of the anti-HIV drug nevirapine

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    Nevirapine (NVP), a non-nucleoside reverse transcriptase inhibitor widely used in combined antiretroviral therapy and to prevent mother-to-child transmission of the human immunodeficiency virus type 1, is associated with several adverse side effects. Using 12-mesyloxy-nevirapine, a model electrophile of the reactive metabolites derived from the NVP Phase I metabolite, 12-hydroxy-NVP, we demonstrate that the nucleophilic core and C-terminal residues of histones are targets for covalent adduct formation. We identified multiple NVP-modification sites at lysine (e.g., H2BK47, H4K32), histidine (e.g., H2BH110, H4H76), and serine (e.g., H2BS33) residues of the four histones using a mass spectrometry-based bottom-up proteomic analysis. In particular, H2BK47, H2BH110, H2AH83, and H4H76 were found to be potential hot spots for NVP incorporation. Notably, a remarkable selectivity to the imidazole ring of histidine was observed, with modification by NVP detected in three out of the 11 histidine residues of histones. This suggests that NVP-modified histidine residues of histones are prospective markers of the drug's bioactivation and/or toxicity. Importantly, NVP-derived modifications were identified at sites known to determine chromatin structure (e.g., H4H76) or that can undergo multiple types of post-translational modifications (e.g., H2BK47, H4H76). These results open new insights into the molecular mechanisms of drug-induced adverse reactions.This work was supported in part by the PRIME-XS project, grant agreement number 262067, funded by the European Union seventh Framework Programme. We also thank Fundação para a Ciência e a Tecnologia (FCT), Portugal, for financial support through projects UID/QUI/00100/2020 (to CQE), RECI/QEQ-MED/0330/2012 and PTDC/QUI-QAN/32242/2017, as well as contract CEECIND/02001/2017 (to A.M.M.A) and doctoral fellowships SFRH/BD/80690/2011 (to SGH), SFRH/BD/75426/2010 (to ILM), and SFRH/BD/102846/2014 (to CC). Joint funding from FCT and the COMPETE Program through grant SAICTPAC/0019/2015 and RNEM-LISBOA-01-0145-FEDER-022125 funding are also gratefully acknowledged. The CRG/UPF Proteomics Unit is part of the “Plataforma de Recursos Biomoleculares y Bioinformáticos (ProteoRed)” supported by grant PT13/0001 of the Instituto de Salud Carlos III (ISCIII
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