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1.
Environ Sci Technol ; 53(16): 9855-9865, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31385515

RESUMO

In this study, we evaluate the main factors driving the exposure of Southern Ocean seabirds to perfluoroalkyl substances (PFASs) across a wide geographic range. Five perfluoroalkane sulfonates (PFSAs, C4-12), 10 perfluoroalkyl carboxylic acids (PFCAs, C4-13), and perfluorooctane sulfonamide (FOSA) were analyzed in plasma (n = 128) from eight species, including penguins, giant petrels, skuas, albatrosses, and shearwaters, breeding at four sites in the Antarctic, sub-Antarctic, and adjacent cool-temperate regions. Mean ∑PFAS concentrations ranged from 0.53 to 53 ng/g wet weight from black-browed albatross to giant petrels, respectively. As expected due to biomagnification, greater concentrations of most PFASs were found in species near the top of marine food webs such as giant petrels. However, our results suggest that other factors, i.e., metabolic capabilities and spatial movements, can mask interspecies differences in PFASs, especially PFCAs, expected from trophic structure. For instance, trans-equatorial migratory seabirds exhibited PFAS levels and profiles that are consistent with northern hemisphere exposure, reflecting their potential biovector role in the global transport of these pollutants. Among resident species, greater concentrations of PFASs, especially long-chain PFCAs, were found in seabirds breeding or foraging north of the Antarctic Circumpolar Current (ACC) than in those restricted to Antarctic/sub-Antarctic distributions. Moreover, composition profiles of PFAS in Antarctic seabirds agree well with those expected from long-range transport. Our results confirm the importance of the ACC in protecting Antarctic food webs from water-phase-transported PFASs.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Alcanossulfonatos , Animais , Regiões Antárticas , Monitoramento Ambiental , Oceanos e Mares
2.
Anal Bioanal Chem ; 409(20): 4905-4913, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28593369

RESUMO

A simplified, miniaturised matrix solid-phase dispersion (MSPD)-based method allowing the simultaneous extraction and purification of contaminants belonging to selected families of regulated persistent organic pollutants (POPs), i.e. polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and penta- to octa-polybrominated diphenyl ethers (PBDEs), and related contaminants of emerging concern, such as deca-BDE and Dechlorane Plus (DP), has been proposed. Wild bird eggs were used as biotic fat-containing model matrices. Once optimised, the procedure allowed sample preparation to be accomplished within 30 min, in a single step, and with minimal sample and reagent consumption and waste generation. These features contributed to speeding up and greening the analytical process as compared to the large-scale multistep procedures for these types of analyses. The method was combined with gas chromatography-quadrupole mass spectrometry (GC-qMS) for PCB and OCP analysis and with GC-negative ion chemical ionisation-quadrupole mass spectrometry (NCI-qMS) for PBDE and DP determination. The complete analytical method provided satisfactory recoveries of the target compounds (above 83% for all analytes, except for PBDE 209, 63%), although as small an amount of sample as 0.300 g was used. The repeatability of the complete procedure was less than 16% (with the only exception for PCB 153, which looked to be affected by an interference). The limits of detection were in all cases lower than 34 pg g-1 dry weight (as calculated for real samples), demonstrating the feasibility of the proposed procedure for accurate determination of the target compounds in biological samples. The proposed procedure was applied to the analysis of the target POPs in unhatched eggs of wild bird species. Graphical abstract Scheme of the miniaturised methodology proposed for environmental monitoring of POPs and related compounds in wild bird eggs.


Assuntos
Ovos/análise , Poluentes Ambientais/análise , Halogênios/análise , Miniaturização , Animais , Aves , Limite de Detecção , Controle de Qualidade , Reprodutibilidade dos Testes
3.
Anal Bioanal Chem ; 404(9): 2765-73, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22899248

RESUMO

Dechlorane Plus (DP) and some of its possible degradation products were measured in eggs from the yellow-legged gull (Larus michahellis) and Audouin's gull (Larus audouinii) from a protected area in the southwestern Mediterranean Sea. Statistically significant differences were found between both gull species, with yellow-legged gull eggs showing the highest average total DP concentration (209 pg/g wet weight). According to stable nitrogen and carbon isotope values, variations in DP concentrations in the gull species studied are explained by foraging behavior and diet rather than by the trophic position. Both DP stereoisomers were quantified in all the samples studied, and a slight enrichment of the anti-DP could have occurred in both species. The quantification of anti-[DP-1Cl] only in ∼58 % of yellow-legged gulls support the hypothesis of a species-dependent factor influencing the bioaccumulation and/or biotransformation of Dechlorane-related compounds. This study reports on the first measurements of Dechlorane-related compounds in biota from the North African continent, contributing to the knowledge about DP environmental fate and distribution. In the light of our results, more research on differences in species-dependent bioaccumulation and biotransformation capabilities as well as ecological effects is encouraged in future Dechlorane-related compound studies.


Assuntos
Charadriiformes/metabolismo , Ovos/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Retardadores de Chama/análise , Hidrocarbonetos Clorados/análise , Compostos Policíclicos/análise , África do Norte , Animais , Mar Mediterrâneo
4.
Adicciones ; 24(4): 301-7, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-23241717

RESUMO

Ekbom syndrome is a mental disorder in which the patient has the monothematic delusion of being infected by parasites. It is an uncommon condition that was initially studied by dermatologists. The exactly etiology is unknown to date, though several causes have been proposed, including metabolic diseases (among other physical causes), psychiatric disorders, drugs, etc. Research has now found a relationship between drug abuse and psychotic symptoms, which appear to be due to altered levels of dopamine at the receptor level. In this article we review the clinical features of the condition and present the case report of an intravenous methylphenidate abuser who developed a delusion of parasitosis.


Assuntos
Estimulantes do Sistema Nervoso Central/efeitos adversos , Delírio de Parasitose/induzido quimicamente , Metilfenidato/efeitos adversos , Psicoses Induzidas por Substâncias/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
5.
Chemosphere ; 286(Pt 3): 131940, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34435575

RESUMO

The aim of the present study was to assess the presence of perfluoroalkyl acids (PFAAs), namely perfluoroalkane sulfonates and perfluoroalkyl carboxylic acids, in Spanish river basins in order to: identify potential spatiotemporal variations; evaluate the effectiveness of the measures implemented for the reduction/elimination of these pollutants; verify the fulfillment of the Environmental Quality Standards (EQSs) in the European Union. PFOS and PFOA were determined in 116 water samples from four sites in the Duero basin, the largest in the Iberian Peninsula, collected seasonally from 2013 to 2020. In addition, 30 fish sample composites from the sample banks of Duero, Tagus, Ebro, Eastern Cantabrian and Catalonian basins were analyzed for 15 PFAAs. Median PFOS and PFOA concentrations were 0.72 and 0.42 ng/L, ranging from values below the limit of quantification (LOQ) to 81 and 22 ng/L, respectively. During the studied period, 51% of water samples were above the EQS of 0.65 ng/L for PFOS. In the case of fish, the PFOS range was

Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/análise , Animais , Monitoramento Ambiental , Fluorocarbonos/análise , Espanha , Água , Poluentes Químicos da Água/análise
6.
Neural Regen Res ; 17(8): 1652-1658, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35017411

RESUMO

In the last decade, attention has become greater to the relationship between neurodegeneration and abnormal insulin signaling in the central nervous system, as insulin in the brain is implicated in neuronal survival, plasticity, oxidative stress and neuroinflammation. Diabetes mellitus and Parkinson's disease are both aging-associated diseases that are turning into epidemics worldwide. Diabetes mellitus and insulin resistance not only increase the possibility of developing Parkinson's disease but can also determine the prognosis and progression of Parkinsonian symptoms. Today, there are no available curative or disease modifying treatments for Parkinson's disease, but the role of insulin and antidiabetic medications in neurodegeneration opens a door to treatment repurposing to fight against Parkinson's disease, both in diabetic and nondiabetic Parkinsonian patients. Furthermore, it is essential to comprehend how a frequent and treatable disease such as diabetes can influence the progression of neurodegeneration in a challenging disease such as Parkinson's disease. Here, we review the present evidence on the connection between Parkinson's disease and diabetes and the consequential implications of the existing antidiabetic molecules in the severity and development of Parkinsonism, with a particular focus on glucagon-like peptide-1 receptor agonists.

7.
Front Neurol ; 11: 594251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324333

RESUMO

Introduction: We aimed to evaluate if prior oral anticoagulation (OAC) and its type determines a greater risk of symptomatic hemorrhagic transformation in patients with acute ischemic stroke (AIS) subjected to mechanical thrombectomy. Materials and Methods: Consecutive patients with AIS included in the prospective reperfusion registry NORDICTUS, a network of tertiary stroke centers in Northern Spain, from January 2017 to December 2019 were included. Prior use of oral anticoagulants, baseline variables, and international normalized ratio (INR) on admission were recorded. Symptomatic intracranial hemorrhage (sICH) was the primary outcome measure. Secondary outcome was the relation between INR and sICH, and we evaluated mortality and functional outcome at 3 months by modified Rankin scale. We compared patients with and without previous OAC and also considered the type of oral anticoagulants. Results: About 1.455 AIS patients were included, of whom 274 (19%) were on OAC, 193 (70%) on vitamin K antagonists (VKA), and 81 (30%) on direct oral anticoagulants (DOACs). Anticoagulated patients were older and had more comorbidities. Eighty-one (5.6%) developed sICH, which was more frequent in the VKA group, but not in DOAC group. OAC with VKA emerged as a predictor of sICH in a multivariate regression model (OR, 1.89 [95% CI, 1.01-3.51], p = 0.04) and was not related to INR level on admission. Prior VKA use was not associated with worse outcome in the multivariate regression model nor with mortality at 3 months. Conclusions: OAC with VKA, but not with DOACs, was an independent predictor of sICH after mechanical thrombectomy. This excess risk was associated neither with INR value by the time thrombectomy was performed, nor with a worse functional outcome or mortality at 3 months.

8.
Rev Neurol ; 69(2): 45-52, 2019 Jul 16.
Artigo em Espanhol | MEDLINE | ID: mdl-31287147

RESUMO

AIM: It has been suggested that the repetitive transcranial magnetic stimulation could be useful as a non-pharmacological treatment for spasticity. The aim of this study was to evaluate the clinical and neurophysiological effects of high-frequency intermittent theta burst stimulation (iTBS) on lower limb spasticity in patients with relapsing multiple sclerosis in a randomized, double-blind placebo controlled trial. PATIENTS AND METHODS: Seventeen patients in the remitting phase of the disease were randomly allocated to sham or magnetic therapy group and underwent iTBS over contralateral motor cortex of the most affected leg once a day for two weeks. Each session consisted of 10 bursts containing three pulses at 50 Hz repeated at 200 ms intervals (5 Hz) every 10 s for a total of 600 stimuli. The iTBS effect was assessed by using clinical (such as the Modified Ashworth Scale) and neuro-physiological (H/M amplitude ratio and cortical silent period duration) parameters. RESULTS: Two-week iTBS over motor cortex of the most affected leg did not produce any significant clinical effect on spasticity. However, it decreases the H/M amplitude ratio and increases duration of cortical silent period but not significantly, in patients with relapsing multiple sclerosis. CONCLUSION: The stimulation protocol used in this study does not have significant therapeutic effect. Therefore, we do recommend further studies as neurophysiological changes were evident.


TITLE: Estimulacion magnetica transcraneal theta-burst intermitente para el tratamiento de la espasticidad en pacientes con esclerosis multiple recurrente: resultados de un ensayo clinico aleatorizado doble ciego.Objetivo. La estimulacion magnetica transcraneal repetitiva podria ser util como tratamiento no farmacologico para la espasticidad. El objetivo de este estudio es reevaluar el efecto clinico y los cambios neurofisiologicos que produce la estimulacion theta-burst intermitente (ETBi) sobre la espasticidad de las extremidades inferiores en pacientes con esclerosis multiple recurrente en un ensayo aleatorizado, doble ciego, controlado con placebo. Pacientes y metodos. Diecisiete pacientes en la fase remitente de la enfermedad fueron aleatoriamente asignados al grupo placebo o al grupo de tratamiento activo mediante estimulacion magnetica transcraneal repetitiva con protocolo ETBi sobre la corteza motora contralateral de la pierna mas afectada. El procedimiento consistio en 10 sesiones diarias durante dos semanas. Cada sesion consistio en 10 rafagas que contenian tres pulsos a 50 Hz repetidos a intervalos de 200 ms (5 Hz) cada 10 s para un total de 600 estimulos. El efecto de ETBi se evaluo mediante el uso de parametros clinicos (como la escala de Ashworth modificada) y neurofisiologicos (ratio de amplitud H/M y duracion del periodo cortical silente). Resultados. Dos semanas de ETBi sobre la corteza motora de la pierna mas afectada no produjeron ningun efecto clinico significativo sobre la espasticidad en pacientes con esclerosis multiple recurrente. Sin embargo, aunque de forma no significativa, se observo disminucion de la ratio de amplitud H/M y un aumento de la duracion del periodo cortical silente. Conclusion. El protocolo de estimulacion utilizado en este estudio no parece tener un efecto terapeutico significativo. Sin embargo, recomendamos estudios adicionales, ya que los cambios neurofisiologicos fueron evidentes.


Assuntos
Esclerose Múltipla/complicações , Espasticidade Muscular/etiologia , Espasticidade Muscular/terapia , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Resultado do Tratamento
9.
Sci Total Environ ; 634: 1657-1668, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29550067

RESUMO

The Stockholm Convention (SC) on Persistent Organic Pollutants (POPs) calls for the Parties' effectiveness evaluation of those measures taken to meet the reduction and eventual elimination of POPs from the environment. With that goal, air concentrations of different POP families have been measured uninterruptedly since 2008 under the Spanish Monitoring Program (SMP) by means of passive air sampling. This work focuses on data for polybrominated diphenyl ethers (PBDEs) determined in a total of 321 samples collected seasonally each year in 5 urban and 7 background sites. Neither significant temporal trends nor significant seasonal variations for total PBDE air burdens were detected. In contrast, significant variations were found among PBDE congeners. Those related to the octa-PBDE formulation significantly decreased in the study period. However, PBDEs related to the penta-formulation showed steady concentrations while PBDE-209, the congener found at the greatest levels, showed increasing or steady levels in most sampling sites. Seasonal variations were also markedly different among congeners. Concentrations of the lightest PBDEs (tri- to penta-substituted) were highly influenced by ambient temperature (T), showing maximum values in summer probably due to higher volatilization rates compared to those of heavier PBDEs. Contrarily, no clear seasonal trends were found for hexa- to deca-PBDEs, which were negatively related to precipitation; thereby, indicating an efficient atmospheric wash out by wet deposition episodes. Regarding spatial patterns, overall significant greater PBDE levels were found in cities compared to background areas, pointing out the role of highly populated areas as sources for these pollutants in Spain. Yet and especially in the case of PBDE-209, our results suggested the presence of significant unknown sources of PBDEs in some background sites. Further monitoring efforts are needed to assess potential unknown sources in the sampling network as well as to ensure temporal trends of these pollutants in Spain.

10.
Sci Total Environ ; 634: 1669-1679, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29685685

RESUMO

Time series (2008-2015) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in ambient air from the Spanish Monitoring Program were analyzed. A total of 321 samples were collected seasonally each year in 5 urban and 7 background sites by means of passive air sampling. Air concentrations were higher at urban than background sites (urban vs. background concentration ranges): PCDD/Fs (26.9-1010 vs. 20.0-357 fg/m3), non-ortho PCBs (0.113-3.14 vs. 0.042-2.00 pg/m3) and mono-ortho PCBs (0.644-41.3 vs. 0.500-32.8 pg/m3). Results showed significant decreases from 2009 for non-ortho PCBs and PCDD/Fs as well as for WHO2006-TEQs. These declines were sharper, and sometimes only significant, in urban places resulting in converging levels at urban and background sites for these pollutants at the end of the study period. In contrast, mono-ortho PCBs did not show any significant variation but a steady flat temporal behavior in their concentrations, suggesting the existence of different sources between mono-ortho and non-ortho PCBs. Seasonality was observed for air burdens of all these POPs. PCDD/Fs were mostly measured at higher concentrations in colder than in hot seasons, and the opposite was true for dl-PCBs. Seasonal variations for PCDD/Fs appeared to be related to changes in their sources (e.g. domestic heating, open burning) rather than to temperature per se. In contrast, environmental temperature dependent factors (e.g. increased partitioning into the gas phase) drove seasonal variations in dl-PCBs instead of seasonal changes in their sources. Regarding spatial patterns, significant greater levels of PCDD/Fs and dl-PCBs were generally found in cities compared to background areas, pointing out the role of densely populated areas as sources for these pollutants in Spain. As proven by our results, long-term monitoring activities are essential to assess and understand temporal behaviors for these POPs, as well as to evaluate the achievement of Stockholm Convention objectives.

11.
Rev Neurol ; 67(11): 436-440, 2018 Dec 01.
Artigo em Espanhol | MEDLINE | ID: mdl-30484276

RESUMO

INTRODUCTION: The behavioural variant of frontotemporal dementia is characterised by progressive social, cognitive and personality deterioration associated with several molecular pathologies of frontotemporal lobar dementia (FTLD): FTLD-tau, FTLD-TDP and FTLD-FUS. Its diagnosis requires pathological studies. CASE REPORT: A 61-year-old male, with a three-year progressive history of behavioural disorder, apathy, poor language skills, perseveration, lack of empathy, bulimia and executive dysfunction. Neuroimaging revealed right-dominant frontal cortical atrophy, and a single-photon emission tomography brain scan showed bilateral frontal hypoperfusion with thalamic and caudate involvement. Clinically, he was diagnosed with probable frontotemporal dementia, behavioural variant. On his death, his brain was donated to the Neurological Tissue Bank and the neuropathological diagnosis was corticobasal degeneration. CONCLUSIONS: Corticobasal degeneration is one of the FTLD-tau tauopathies. The 2013 diagnostic criteria for corticobasal degeneration include executive dysfunction and behavioural and personality disorders similar to those of this patient as a clinical phenotype. The anatomoclinical case presented illustrates the absence of any correlation between the clinical phenotype and the underlying neuropathological diagnosis in frontotemporal dementia, and the need to conduct a histopathological study in order to reach a definitive diagnosis.


TITLE: Variante conductual de la demencia frontotemporal como forma de presentacion de la degeneracion corticobasal.Introduccion. La variante conductual de la demencia frontotemporal se caracteriza por el deterioro progresivo de la personalidad, social y cognitivo que se asocia con diversas patologias moleculares de la degeneracion lobar frontotemporal (DLFT): DLFT-tau, DLFT-TDP y DLFT-FUS. El estudio anatomopatologico es necesario para su diagnostico. Caso clinico. Varon de 61 años, con un cuadro progresivo de tres años de evolucion de trastorno conductual, apatia, lenguaje pobre, perseveracion, falta de empatia, bulimia y disfuncion ejecutiva. En la neuroimagen se objetivo una atrofia cortical frontal de predominio derecho, y en la tomografia simple por emision de foton unico cerebral, una hipoperfusion frontoparietotemporal bilateral con afectacion de talamos y caudados. Clinicamente, se le diagnostico probable demencia frontotemporal, variante conductual. Tras su fallecimiento, se dono el cerebro al Banco de Tejidos Neurologicos y el diagnostico neuropatologico fue el de degeneracion corticobasal. Conclusiones. La degeneracion corticobasal es una de las taupatias de la DLFT-tau. Los criterios diagnosticos de degeneracion corticobasal de 2013 contemplan como fenotipo clinico la disfuncion ejecutiva, las alteraciones conductuales y de personalidad similar al de este paciente. El caso anatomoclinico presentado ilustra la falta de correlacion entre el fenotipo clinico y el diagnostico neuropatologico subyacente en la demencia frontotemporal, y la necesidad de realizar el estudio histopatologico para llegar al diagnostico definitivo.


Assuntos
Comportamento , Demência Frontotemporal/psicologia , Degenerações Espinocerebelares/etiologia , Degenerações Espinocerebelares/patologia , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade
12.
Environ Pollut ; 217: 107-13, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26905212

RESUMO

Within the framework of the Spanish monitoring program, this study reports on air concentration of DDTs, HCB, HCHs, NDL-PCBs, DL-PCBs, PCDD/Fs and PBDEs measured during the five-year sampling period 2008-2013. Spanish coastal remote and urban locations were studied using PUF disk passive air samplers which were deployed and collected every three months. Despite the wide range of concentrations measured for most contaminants, a common pattern of relative abundance (median values): NDL-PCBs (36.6 pg/m(3)) > HCB (24.8 pg/m(3)) ≈ HCHs (17.9 pg/m(3)) ≈ DDTs (16.6 pg/m(3)) > PBDEs (3.65 pg/m(3)) > DL-PCBs (2.99 pg/m(3)) >> PCDD/Fs (0.060 pg/m(3)) was found fairly consistent across most seasons and locations. Nevertheless, important variations in yearly concentrations were measured for different POPs. In general, higher levels of DDTs, HCHs, NDL-PCBs, DL-PCBs and PCDD/Fs were found in urban sites highlighting important differences between remote and urban sampling locations for most target contaminants. Greater concentrations of the banned organochlorine pesticides in urban locations suggested the existence of unexpected pointed sources that need to be further investigated and characterized. The limited dataset collected thus far rendered no clear temporal trends for most study target compounds, which emphasizes the necessity of the Spanish monitoring program future maintenance in time.


Assuntos
Poluentes Atmosféricos/análise , Congressos como Assunto , Monitoramento Ambiental/legislação & jurisprudência , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Estações do Ano , Espanha , Fatores de Tempo
13.
Environ Pollut ; 212: 307-315, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26854700

RESUMO

The impact of pollution caused by severe anthropogenic pressure in the Mediterranean Sea, an important biodiversity hotspot, requires continuous research efforts. Sources of highly toxic chemicals such as Persistent Organic Pollutants (POPs) are misunderstood in representative Mediterranean species, which limits our capability to establish proper conservation strategies. In the present study, eggs of Audouin's and yellow-legged gulls (Larus audouinii and L. michahellis) were used to investigate the trophic sources, as measured by δ(13)C, δ(15)N, and δ(34)S, of legacy POPs, in particular, polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and non-ortho polychlorinated biphenyls (no-PCBs), as well as recently-regulated POPs, e.g., polybrominated diphenyl ethers (PBDEs). Special attention was paid to the usefulness of rarely-explored δ(34)S ratios in explaining POP exposure in wildlife, and δ(34)S was the isotopic ratio that best explained POP variations among gulls in most cases, thus demonstrating its usefulness for understanding POP exposure in wildlife. Significant relationships between stable isotope signatures and POP concentrations revealed increasing levels of no-PCBs and low halogenated PCDD/Fs and PBDEs in Mediterranean gulls as the consumption of marine resources increases. In contrast, highly chlorinated and brominated congeners appeared to preferentially accumulate in gulls feeding primarily on refuse from dump sites and terrestrial food webs. The use of suitable dietary tracers in the study of POPs in yellow-legged gulls revealed the importance of dump sites as a source of POPs in Mediterranean seabirds, which has not previously been reported. In contrast, the preferential accumulation through marine food webs of low chlorinated PCCD/Fs and no-PCBs, which show the highest toxic equivalents factors (TEFs), led to a significantly greater toxicological concern in Audouin's as compared to yellow-legged gulls. Audouin's gull exposure to POPs appears primarily related to the pelagic food webs commonly exploited by fisheries, highlighting the need for further research given the potential impact on human consumption.


Assuntos
Charadriiformes/metabolismo , Dibenzofuranos Policlorados/análise , Poluentes Ambientais/análise , Éteres Difenil Halogenados/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Animais , Dibenzofuranos Policlorados/metabolismo , Ecologia , Ovos/análise , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Pesqueiros , Cadeia Alimentar , Éteres Difenil Halogenados/metabolismo , Humanos , Isótopos , Mar Mediterrâneo , Bifenilos Policlorados/metabolismo , Dibenzodioxinas Policloradas/metabolismo
14.
Sci Total Environ ; 573: 1380-1389, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27453143

RESUMO

Foraging ecology and the marine regions exploited by Antarctic seabirds outside of breeding strongly influence their exposure to persistent organic pollutants (POPs). However, relationships between them are largely unknown, an important knowledge gap given that many species are capital breeders and POPs may be deleterious to seabirds. This study investigates the relationship between Antarctic seabird foraging ecology (measured by δ13C and δ15N) and POPs accumulated in their eggs prior to breeding. Organochlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and dechlorane plus (DP) were measured in eggs of chinstrap, Adélie, and gentoo penguins (Pygoscelis antarctica, P. adeliae, P. papua), as well as south polar skua (Catharacta maccormicki), sampled on King George Island. Total POP levels were as follows: skua (3210±3330ng/g lipid weight)>chinstrap (338±128ng/g)>Adélie (287±43.3ng/g)>gentoo (252±49.4ng/g). Trophic position and pre-breeding foraging sites were important in explaining POP accumulation patterns across species. The most recalcitrant compounds were preferentially accumulated in skuas, occupying one trophic level above penguins. In contrast, their Antarctic endemism, coupled with influence from cold condensation of pollutants, likely contributed to penguins exhibiting higher concentrations of more volatile compounds (e.g., hexachlorobenzene, PCB-28 and -52) than skuas. Regional differences in penguin pre-breeding foraging areas did not significantly affect their POP burdens, whereas the trans-equatorial migration and foraging sites of skuas were strongly reflected in their pollutant profiles, especially for PBDEs and DPs. Overall, our results provide new insights on migratory birds as biovectors of POPs, including non-globally regulated compounds such as DP, from northern regions to Antarctica.


Assuntos
Charadriiformes/fisiologia , Exposição Ambiental , Comportamento Alimentar , Spheniscidae/fisiologia , Poluentes Químicos da Água/metabolismo , Animais , Regiões Antárticas , Isótopos de Carbono/análise , Monitoramento Ambiental , Isótopos de Nitrogênio/análise , Óvulo/química
15.
PeerJ ; 3: e1171, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26339549

RESUMO

Background. The Late Cretaceous is a keystone period to understand the origin and early radiation of Crocodylia, the group containing all extant lineages of crocodilians. Among the taxa described from the latest Cretaceous of Europe, the genus Allodaposuchus is one of the most common but also one of the most controversial. However, because of its fragmentary record, several issues regarding its phylogenetic emplacement and its ecology remain unsolved or unknown. The discovery of a single specimen attributed to Allodaposuchus, represented by both cranial and postcranial remains, from the Casa Fabà site (Tremp Basin, NE Spain) in the lower red unit of the Tremp Fm. (early Maastrichtian, Late Cretaceous) offers a unique opportunity to deepen in the phylogenetic relationships of the group and its ecological features. Methods. The specimen is described in detail, and CT scan of the skull is performed in order to study the endocranial morphology as well as paratympanic sinuses configuration. In addition, myological and phylogenetic analyses are also carried out on the specimen for to shed light in ecological and phylogenetic issues, respectively. Results. The specimen described herein represents a new species, Allodaposuchus hulki sp. nov., closely related to the Romanian A. precedens. The CT scan of the skull revealed an unexpected paratympanic sinuses configuration. Allosaposuchus hulki exhibits an "anterodorsal tympanic sinus" not observed in any other extant or extinct crocodilian. The caudal tympanic recesses are extremely enlarged, and the expanded quadratic sinus seems to be connected to the middle-ear channel. Phylogenetic analyses confirm the emplacement of the informal taxonomic group 'Allodaposuchia' at the base of Crocodylia, being considered the sister group of Borealosuchus and Planocraniidae. Discussion. Although this is a preliminary hypothesis, the unique paratympanic configuration displayed by A. hulki suggests that it could possess a high-specialized auditory system. Further, the large cranial cavities could help to reduce the weight of the cranium. Concerning the postcranial skeleton, Allodaposuchus hulki shows massive and robust vertebrae and forelimb bones, suggesting it could have a bulky body. The myological study performed on the anterior limb elements supports this interpretation. In addition, several bone and muscular features seem to point at a semi-erected position of the forelimbs during terrestrial locomotion. Taking all the above results into consideration, it seems plausible to suggest that A. hulki could conduct large incursions out of the water and have a semi-terrestrial lifestyle.

16.
Eur J Med Chem ; 100: 210-22, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26092446

RESUMO

We have synthesized and assayed dimethylaminophenyl, pyrrolidin-1-ylphenyl and carbazole containing phenstatins and isocombretastatins as analogues of the highly potent indoleisocombretastatins with extended or reduced ring sizes. This is an attempt to explore beyond the structural constraints of the X-ray crystal structures the zone of the colchicine site where the tropolone ring of colchicine binds to tubulin (zone 1). The isocombretastatins display up to 30 fold increased water solubility when compared with combretastatin A-4, potent inhibition of tubulin polymerization, and nanomolar cytotoxicities against several human cancer cell lines irrespective of the size of the B ring. On the other hand, substitutions ortho to the nitrogen cause an important reduction in potency. We have also shown that representative compounds inhibit autophagy. These results show that zone 1 can adapt to systems of different size as far as they stay in a common plane, but does not tolerate substituents protruding above or below it. These results can help in the understanding of the binding modes of structures with similar systems and in the design of new colchicine site ligands.


Assuntos
Antineoplásicos/farmacologia , Colchicina/farmacologia , Nitrogênio/química , Estilbenos/química , Estilbenos/farmacologia , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Sítios de Ligação/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colchicina/síntese química , Colchicina/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Tamanho da Partícula , Relação Estrutura-Atividade
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