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1.
Conserv Biol ; : e14288, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38757477

RESUMO

Sea-level rise (SLR) is expected to cause major changes to coastal wetlands, which are among the world's most vulnerable ecosystems and are critical for nonbreeding waterbirds. Because strategies for adaptation to SLR, such as nature-based solutions and designation of protected areas, can locally reduce the negative effects of coastal flooding under SLR on coastal wetlands, it is crucial to prioritize adaptation efforts, especially for wetlands of international importance for biodiversity. We assessed the exposure of coastal wetlands important for nonbreeding waterbirds to projected SLR along the Mediterranean coasts of 8 countries by modeling future coastal flooding under 7 scenarios of SLR by 2100 (from 44- to 161-cm rise) with a static inundation approach. Exposure to coastal flooding under future SLR was assessed for 938 Mediterranean coastal sites (≤30 km from the coastline) where 145 species of nonbreeding birds were monitored as part of the International Waterbird Census and for which the monitoring area was delineated by a polygon (64.3% of the coastal sites monitored in the Mediterranean region). Thirty-four percent of sites were threatened by future SLR, even under the most optimistic scenarios. Protected study sites and study sites of international importance for waterbirds were, respectively, 1.5 and 2 times more exposed to SLR than the other sites under the most optimistic scenario. Accordingly, we advocate for the development of a prioritization scheme to be applied to these wetlands for the implementation of strategies for adaptation to SLR to anticipate the effects of coastal flooding. Our study provides major guidance for conservation planning under global change in several countries of the Mediterranean region.


Exposición de los humedales de importancia para las aves acuáticas no reproductoras al incremento del nivel del mar en el Mediterráneo Resumen Se espera que el incremento en el nivel del mar (INM) cause cambios importantes en los humedales costeros, los cuales se encuentran entre los ecosistemas más vulnerables y son críticos para las aves acuáticas no reproductoras. Es crucial la priorización de los esfuerzos de adaptación, especialmente en los humedales con importancia internacional para la biodiversidad, ya que las estrategias de adaptación ante el INM, como las soluciones basadas en la naturaleza y la designación de áreas protegidas, pueden reducir localmente los efectos negativos de las inundaciones costeras por INM en los humedales costeros. Evaluamos la exposición de los humedales costeros con importancia para las aves acuáticas no reproductoras ante el INM proyectado en las costas del Mediterráneo en ocho países con un modelo de inundaciones costeras en el futuro bajo siete escenarios de INM para el año 2100 (de 44 a 161 cm) con un enfoque de inundación estática. Evaluamos la exposición a las inundaciones costeras bajo el INM futuro en 938 sitios costeros del Mediterráneo (≤ 30 km a partir de la costa), en donde monitoreamos a 145 especies de aves no reproductoras como parte del Censo Internacional de Aves Acuáticas y para los cuales el área de monitoreo estuvo delineada con un polígono (64.3% de los sitios costeros monitoreados en la región Mediterránea). El 34% de los sitios se vio amenazado por el INM en el futuro, incluso con los escenarios más optimistas. Los sitios de estudio protegidos y los sitios de estudio de importancia internacional para las aves acuáticas estuvieron expuestos 1.5 y 2 veces más al INM que otros sitios con el escenario más optimista. De acuerdo con esto, abogamos por el desarrollo de un esquema de priorización para aplicarse en estos humedales para la implementación de estrategias de adaptación al INM para anticipar los efectos de las inundaciones costeras. Nuestro estudio proporciona información importante para la planeación de la conservación bajo el cambio global en varios de los países del Mediterráneo.

2.
Pharm Dev Technol ; 23(6): 561-572, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28758819

RESUMO

The aim of this study was to identify pharmaceutical issues encountered during regulatory review in European Procedures. A database of issues from Day 70 assessment reports of 150 EU procedures was compiled; most procedures were for generics (108). Frequencies of common deficiencies have been calculated and summarised for use of all stakeholders. Out of the 150 procedures reviewed, covering 309 products, a total of 4796 concerns were identified. Of these concerns, 167 were Potential Serious Risks to Public Health, 67 were raised on drug substance and 100 on the drug product. The distribution of total concerns was as follows: 2168 concerns on drug substance and 2584 on drug product. Most concerns raised were on control of drug substance and drug product (834 & 626 for 3.2.S.4 and 3.2.P.5, respectively), followed by concerns on the manufacturing (482 & 564 for 3.2.S.2 and 3.2.P.3, respectively) and stability 147 & 398 for 3.2.S.7 and 3.2.P.8, respectively). In conclusion, the frequencies and trends of identified deficiencies together with their impact were discussed from a regulatory point of view. The main findings indicate that applicants would benefit from following published guidelines so that delays in the registration of medicines could be avoided.


Assuntos
Indústria Farmacêutica/legislação & jurisprudência , Legislação de Medicamentos , Marketing/legislação & jurisprudência , Europa (Continente) , Humanos , Malta , Controle de Qualidade
3.
Nat Commun ; 14(1): 3665, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37402727

RESUMO

Plastic pollution is distributed patchily around the world's oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species.


Assuntos
Plásticos , Resíduos , Animais , Plásticos/toxicidade , Resíduos/análise , Monitoramento Ambiental , Oceanos e Mares , Aves , Oceano Índico
4.
Eur J Pharmacol ; 569(3): 163-70, 2007 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-17603033

RESUMO

A novel anionic background conductance (I(AB)) in cardiac ventricular myocytes has recently been identified but at present there is comparatively little information on its pharmacological modulation. This study investigated the effects of on I(AB) of four pyrethroid agents tefluthrin (a selective activator of this current), tetramethrin, fenpropathrin and alpha-cypermethrin in addition to other well known chloride channel modulators (chlorotoxin, gadolinium and picrotoxin). Guinea-pig ventricular myocytes were isolated using an enzymatic and mechanical dispersion procedure and all electrophysiological measurements were made using the whole-cell patch-clamp technique. In contrast to other anion conductances (stretch- or volume-regulated chloride current (I(Cl,vol)), a cAMP-dependent Cl(-) current (I(Cl,cAMP))) I(AB) was augmented by tefluthrin, fenpropathrin, alpha-cypermethrin (but not tetramethrin). I(AB) was insensitive to chlorotoxin, gadolinium and picrotoxin. Thus, I(AB) exhibits a distinct pharmacological profile from other known cardiac anion conductances.


Assuntos
Gadolínio/farmacologia , Picrotoxina/farmacologia , Piretrinas/farmacologia , Venenos de Escorpião/farmacologia , Animais , Ânions/metabolismo , Canais de Cloreto/efeitos dos fármacos , Canais de Cloreto/metabolismo , AMP Cíclico/metabolismo , Ciclopropanos/farmacologia , Condutividade Elétrica , Eletrofisiologia , Cobaias , Ventrículos do Coração , Hidrocarbonetos Fluorados/farmacologia , Masculino , Miócitos Cardíacos , Técnicas de Patch-Clamp
5.
Curr Opin Support Palliat Care ; 9(4): 333-45, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26509859

RESUMO

PURPOSE OF REVIEW: Multimodal management has been proposed as key to any effective drug intervention in cachexia. This article attempts to reflect on clinical and regulatory considerations of multimodal management treatment as a regulatory requirement in anticachexia drug therapy. To date, no European Union (EU) regulatory guidelines have been published and therefore this review could attempt to present and discuss some central issues to consider when developing an anticachexia drug. RECENT FINDINGS: The following themes are considered: EU regulatory pathways for drug approval (conditional and exceptional circumstances as well as adaptive licensing); selection criteria for randomized clinical trials allowing the identification and characterization of the population of interest that is an at-risk population with undisputable clinical need; issues related to primary and secondary outcome measures that are adequate to determine the efficacy of the intervention and the approach for the development of clinical biomarkers for cachexia. SUMMARY: Conversely, the incorporation of multimodal treatment in anticachexia drug therapy is expected to increase the effectiveness of intervention. This aspect is the aspect that appeals to pharmaceutical companies; however, at the same time, this raises regulatory and clinical issues that need to be kept in mind when designing randomised clinical trials.


Assuntos
Caquexia/tratamento farmacológico , Gerenciamento Clínico , Caquexia/psicologia , Caquexia/terapia , Terapia Combinada , Aconselhamento , Dieta , Aprovação de Drogas/legislação & jurisprudência , União Europeia , Exercício Físico , Humanos , Cuidados Paliativos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos
8.
Biochem Biophys Res Commun ; 292(1): 208-15, 2002 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-11890694

RESUMO

This report describes for the first time a novel anionic background current (I(AB)) identified in guinea-pig isolated ventricular myocytes. It also shows that I(AB) has both novel and differential pharmacology from other (cardiac) chloride currents. Using the whole-cell patch-clamp technique and external anion substitution, I(AB) was found to be outwardly rectifying and highly permeable to NO(-)(3), with a relative permeability sequence of NO(-)(3) > I(-) > Cl(-). I(AB) was not blocked by 50 microM DIDS, by hypertonic external solution, or by the nonselective protein kinase inhibitor H7-DHC. Exposure to the pyrethroid agent tefluthrin (10 microM) increased the current density of I(AB) significantly at positive voltages (P < 0.05), but had no significant effect on other cardiac chloride currents. We conclude that I(AB) possesses a distinct pharmacology and does not fall into the three major classes of cardiac chloride conductance commonly reported.


Assuntos
Coração/fisiologia , Inseticidas/farmacologia , Piretrinas/farmacologia , Potenciais de Ação , Animais , Ânions/metabolismo , Células Cultivadas , Canais de Cloreto/fisiologia , Condutividade Elétrica , Cobaias , Coração/efeitos dos fármacos , Ventrículos do Coração/citologia , Transporte de Íons/efeitos dos fármacos , Técnicas de Patch-Clamp
9.
Pflugers Arch ; 448(5): 478-89, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15138823

RESUMO

CsCl has been shown to be arrhythmogenic in-vivo and to cause early afterdepolarizations (EADs) in isolated cardiac preparations, but the underlying electrophysiological mechanisms are ill-defined. To elucidate these actions further, the effects of extracellular solutions containing 3 mM CsCl and either 2 mM KCl (Cs2K solution) or 5 mM KCl (Cs5K solution) on membrane potential and ionic currents in rat and guinea-pig ventricular myocytes were compared. Cs2K solution rapidly and reversibly inhibited outward I(K1), and reduced other K(+) currents by about 20%. Current-clamped myocytes were rapidly hyperpolarized by this solution and action potentials were prolonged, but EADs were not observed. In contrast, EADs were triggered by E-4031, H(2)O(2), and the pyrethroid tefluthrin. Membrane-potential changes reversed after replacing Cs2K with Cs5K solution, with the recovery of 50% of outward I(K1). These results suggest that Cs2K solution inhibited I(K1) and caused a late prolongation of the action-potential duration, but the affected membrane potentials were too negative to elicit EAD mechanisms. In isolated hearts perfused with modified Tyrode's, Cs2K, and Cs5K solutions, bradycardia and arrhythmias were evoked by both CsCl-containing solutions. A comparison of such results with the effects of these solutions on myocytes suggests that I(K1) inhibition and EADs in ventricular myocytes are unlikely to be involved in arrhythmogenesis under our conditions.


Assuntos
Arritmias Cardíacas/etiologia , Césio/farmacologia , Cloretos/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Animais , Cobaias , Ventrículos do Coração/efeitos dos fármacos , Masculino , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp , Canais de Potássio/efeitos dos fármacos , Ratos
10.
Clin Exp Pharmacol Physiol ; 31(3): 134-44, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15008955

RESUMO

1. There are no effective ways of screening for potential modulators of volume-regulated anion channels in their native cell type. Generally, cell lines are used for this purpose. Using HeLa and C6 glioma cells, we identified the pyrethroids as a novel class of compounds that inhibit taurine efflux through volume-regulated anion transport pathways in these cells. Subsequently, we examined their effects on volume-regulated anion channels in guinea-pig ventricular myocytes to determine whether results obtained using cell lines could be extrapolated to other tissues. 2. Tetramethrin inhibited taurine efflux in both HeLa and C6 glioma cells with Ki values of approximately 26 and 16 micro mol/L, respectively. Bioallethrin and fenpropathrin inhibited volume-sensitive taurine efflux from C6 glioma cells, but not from HeLa cells. The Ki values for bioallethrin and fenpropathrin were 70 and 59 micro mol/L, respectively. 3. Volume-sensitive I- efflux was observed in HeLa cells but not in C6 glioma cells, suggesting that the taurine efflux pathway in C6 glioma cells may be different to that of the I- efflux pathway. Cyfluthrin, tetramethrin, fenpropathrin, tefluthrin and bioallethrin all significantly inhibited volume-sensitive I- efflux from HeLa cells at 100 micro mol/L. 4. Patch-clamp experiments have shown inhibition of ICl,vol in guinea-pig ventricular myocytes by fenpropathrin, but not tetramethrin or cypermethrin, at 100 micro mol/L. This revealed that further differences exist between ICl,vol in guinea-pig ventricular myocytes and the anion transport pathways in C6 glioma and HeLa cells. 5. In conclusion, we have shown that pyrethroids differentially inhibit volume-regulated anion and taurine efflux in a number of cell types. Because these compounds have different effects in different cells, it is likely that: (i) more than one pathway is involved in the volume-sensitive transport of anions and organic osmolytes; and (ii) the molecular identities of the channels underlying anion transport are different. Finally, for the reasons given above, care should be taken when extrapolating data from one cell type to another. However, in the absence of an existing high-throughput screen, taurine efflux still represents a viable route for the identification of potential modulators of volume-regulated ion channels.


Assuntos
Ânions/metabolismo , Piretrinas/farmacologia , Animais , Transporte Biológico Ativo , Linhagem Celular Tumoral , Canais de Cloreto/efeitos dos fármacos , Canais de Cloreto/fisiologia , Cobaias , Células HeLa , Humanos , Técnicas In Vitro , Iodetos/metabolismo , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/fisiologia , Concentração Osmolar , Técnicas de Patch-Clamp , Ratos , Taurina/metabolismo
11.
Clin Exp Pharmacol Physiol ; 31(1-2): 86-95, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14756690

RESUMO

1. The effects of clomiphene (CLM) on cardiac outward K+ current components from rat isolated ventricular myocytes were investigated using the whole-cell patch-clamp technique. Clomiphene (10 micromol/L) significantly inhibited both peak (Ipeak) and end-pulse (Ilate) outward currents (elicited by a 500 msec voltage step from -40 to +50 mV in the presence of K+-containing intracellular and extracellular solutions) by approximately 37% (n = 6; P < 0.01) and 49% (n = 6; P < 0.01), respectively. In contrast, CLM had no effect on outward currents when K+-free solutions were used. 2. A double-pulse protocol and Boltzmann fitting were used to separate individual K+ current components on the basis of their voltage-dependent inactivation properties. At potentials positive to -80 mV, two inactivating transient outward components (Ito) and (IKx) and a non-inactivating steady state component (Iss) could be distinguished. 3. Clomiphene inhibited both Ito and Iss. The maximal block of Ito and Iss induced by CLM (100 micromol/L) was approximately 61% (n = 5) and 43% (n = 5) with IC50 values of 1.54 +/- 0.39 and 2.2 +/- 0.4 micromol/L, respectively. In contrast, the peak magnitude of IKx was unaltered by CLM, although its time-course of inactivation was accelerated. 4. Further experiments whereby myocytes were superfused with the vasoactive peptide endothelin (ET)-1 (20 nmol/L) revealed that CLM (10 micro mol/L) completely abolished the ET-1-sensitive component of Iss. 5. Our findings demonstrate, for the first time, the effects of CLM on distinct cardiac K+ current components and show that CLM modulates the voltage-gated K+ current components Ito and IKx and inhibits the steady state outward current Iss in rat ventricular myocytes.


Assuntos
Clomifeno/farmacologia , Antagonistas de Estrogênios/farmacologia , Fármacos para a Fertilidade Feminina/farmacologia , Miócitos Cardíacos/metabolismo , Bloqueadores dos Canais de Potássio , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/metabolismo , Algoritmos , Animais , Eletrofisiologia , Endotelina-1/metabolismo , Endotelina-1/farmacologia , Ventrículos do Coração/citologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Técnicas de Patch-Clamp , Potássio/farmacologia , Ratos , Ratos Wistar , Receptores de Endotelina/efeitos dos fármacos , Receptores de Endotelina/metabolismo
12.
J Pharmacol Exp Ther ; 303(1): 282-92, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12235262

RESUMO

The aim of this study was to determine the effects of the antiestrogen agent clomiphene on cardiac anionic and cationic sarcolemmal ion channels. Whole-cell recordings were made from rat and guinea pig ventricular myocytes. Clomiphene inhibited the volume-regulated chloride current [I(Cl,vol), activated by cell swelling after hypotonic shock (approximately 145 mOsM)] with an IC(50) value of approximately 9.4 microM. In contrast, at concentrations up to 100 microM, clomiphene failed to inhibit both the chloride current activated by cyclic AMP (I(Cl,cAMP)) and the anionic background current (I(AB)). At 10 microM, clomiphene blocked the voltage-gated fast sodium current and the L-type calcium current (I(Ca,L)) in both species. The voltage-independent fractional block of I(Ca,L) induced by clomiphene (10 microM) was approximately 82%, this concentration also inhibited the inwardly rectifying K(+) current with a fractional current block of approximately 26% at -90 mV. Fractional block of outward current at +70 mV in rat was approximately 25%, implying that delayed rectifying K(+) channels were also affected by clomiphene. We conclude that clomiphene shows selectivity for I(Cl,vol) over I(Cl,cAMP) and I(AB) and therefore represents a useful tool for studying chloride conductances in isolated ventricular myocytes with interfering currents blocked. However, due to its effects on cation conductances it would be of little value in this regard for other types of in vitro or in vivo experiments.


Assuntos
Clomifeno/farmacologia , Moduladores de Receptor Estrogênico/farmacologia , Coração/fisiologia , Canais Iônicos/fisiologia , Potenciais da Membrana/fisiologia , Sarcolema/fisiologia , Animais , Células Cultivadas , Canais de Cloreto/efeitos dos fármacos , Canais de Cloreto/fisiologia , Cobaias , Coração/efeitos dos fármacos , Ventrículos do Coração , Canais Iônicos/antagonistas & inibidores , Cinética , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/fisiologia , Sarcolema/efeitos dos fármacos , Canais de Sódio/efeitos dos fármacos , Canais de Sódio/fisiologia
13.
Biochem Biophys Res Commun ; 318(2): 556-61, 2004 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-15120636

RESUMO

The acquired form of the long-QT syndrome (LQTS) is a major safety consideration for the development and subsequent use of both cardiac and non-cardiac drugs; it is usually associated with pharmacological inhibition of cardiac HERG-encoded potassium channels. Clomiphene is an anti-estrogen agent used extensively in the treatment of infertility and is not associated with a risk of QT interval prolongation, in contrast to a structurally related compound tamoxifen. We describe here a potent inhibitory effect (IC(50) = 0.18 microM) of clomiphene on HERG ionic current (I(HERG)) recorded from a mammalian cell line expressing HERG channels. Inhibition of I(HERG) by clomiphene showed voltage-dependence and developed quickly following membrane depolarisation, indicating contingency of block on HERG channel gating. At 100 nM, clomiphene and the related anti-estrogen tamoxifen produced similar levels of I(HERG) blockade (p > 0.05). Experiments on guinea-pig isolated perfused hearts revealed that, despite its inhibitory action on I(HERG), clomiphene produced no significant effect at 1 microM on uncorrected QT interval (p > 0.1) nor on rate-corrected QT interval (QT(c); p > 0.1 for QT(c) determined using Van de Water's formula). The disparity between clomiphene's potent I(HERG) inhibition and its lack of effect on the QT interval underscores the notion that I(HERG) pharmacology may best be used alongside other screening methods when investigating the QT-prolonging tendency and related cardiotoxicity of non-cardiac drugs.


Assuntos
Clomifeno/farmacologia , Antagonistas de Estrogênios/farmacologia , Coração/efeitos dos fármacos , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/efeitos dos fármacos , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Eletrocardiografia , Eletrofisiologia , Cobaias , Coração/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Síndrome do QT Longo , Masculino , Miocárdio/metabolismo , Técnicas de Patch-Clamp , Canais de Potássio/metabolismo , Tamoxifeno/farmacologia
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