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- Retinoic acid differentially affects in vitro proliferation, differentiation and mineralization of two fish bone-derived cell lines: Different gene expression of nuclear receptors and ECM proteinsPublication . Fernández, Ignacio; Tiago, Daniel; Laizé, Vincent; Cancela, Leonor; Gisbert, EnricRetinoic acid (RA), the main active metabolite of vitamin A, regulates vertebrate morphogenesis through signaling pathways not yet fully understood. Such process involves the specific activation of retinoic acid and retinoid X receptors (RARs and RXRs), which are nuclear receptors of the steroid/thyroid hormone receptor superfamily. Teleost fish are suitable models to study vertebrate development, such as skeletogenesis. Cell systems capable of in vitro mineralization have been developed for several fish species and may provide new insights into the specific cellular and molecular events related to vitamin A activity in bone, complementary to in vivo studies. This work aims at investigating the in vitro effects of RA (0.5 and 12.5 μM) on proliferation, differentiation and extracellular matrix (ECM) mineralization of two gilthead seabream bone-derived cell lines (VSa13 and VSa16), and at identifying molecular targets of its action through gene expression analysis. RA induced phenotypic changes and cellular proliferation was inhibited in both cell lines in a cell type-dependent manner (36–59% in VSa13 and 17–46% in VSa16 cells). While RA stimulated mineral deposition in VSa13 cell cultures (50–62% stimulation), it inhibited the mineralization of extracellular matrix in VSa16 cells (11–57% inhibition). Expression of hormone receptor genes (rars and rxrs), and extracellular matrix-related genes such as matrix and bone Gla proteins (mgp and bglap), osteopontin (spp1) and type I collagen (col1a1) were differentially regulated upon exposure to RA in proliferating, differentiating and mineralizing cultures of VSa13 and VSa16 cells. Altogether, our results show: (i) RA affects proliferative and mineralogenic activities in two fish skeletal cell types and (ii) that during phenotype transitions, specific RA nuclear receptors and bone-related genes are differentially expressed in a cell type-dependent manner.
- Impact of ecotourism on the fish fauna of Bonito region (Mato Grosso do Sul State, Brazil): ecological, behavioural and physiological measuresPublication . Lima, Ana Carolina; Assis, J.; Sayanda, Diogo; Sabino, Jose; Oliveira, Rui F.Bonito, in Mato Grosso do Sul State, is an important destination for ecotourism in Brazil and the main challenge of sustainable ecotourism here has been to accommodate and adjust the increase of tourism without compromising the ecological integrity of the local ecosystems. In this study we aimed to assess the environmental impact of ecotourism on the fish fauna of Sucuri River in Bonito by integrating ecological, behaviour and physiological criteria and using the fish species Crenicichla lepidota and Moenkhausia bonita as indicators. Two distinct sites were defined to collect data: (1) affected daily by ecotourism (Tourism) and (2) undisturbed (No Tourism). The "stationary point count" method was performed to assess variations in ecological parameters and "ad libitum" and focal animal methods were used to collect behaviour data. The cortisol response of M. bonita to a stress protocol was measured from holding-water. Results showed a significantly increase in species richness, density and diversity at the Tourism site. Nevertheless, behaviour patterns indicated a higher stress at the Tourism site for both species as well higher cortisol levels for M. bonita. In opposition to the ecological measures, the behaviour and physiological ones may be interpreted as an early sign of negative impact caused by ecotourism, prior to changes at community level.
- XV Encontro Nacional de Educação em Ciências: livro de resumosPublication . Coelho, Ana Cristina; Paixão, FátimaA Escola Superior de Educação e Comunicação da Universidade do Algarve acolhe, em 2014, o XV Encontro Nacional de Educação em Ciências (XV ENEC). Sob o mote Tendências atuais em educação em ciências, o XV ENEC pretende constituir uma oportunidade de partilha e discussão de questões relacionadas com o ensino e aprendizagem, o desenvolvimento profissional de educadores e professores, o currículo e as políticas educativas, a relação entre a escola e a comunidade, a inovação didática e a formação em ciências físicas e naturais. Reconhecendo a importância das tecnologias educativas e o benefício da interação das ciências com outras áreas do conhecimento, convidamos, assim, ao diálogo entre as ciências e as artes, a literatura, as ciências sociais e as ciências do desporto.
- Nematode and Arthropod Genomes Provide New Insights into the Evolution of Class 2 B1 GPCRsPublication . Cardoso, João CR; Félix, Rute C.; Power, DeborahNematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes.
- Cephalopods in neuroscience: regulations, research and the 3RsPublication . Fiorito, Graziano; Affuso, Andrea; Anderson, David B; Basil, Jennifer; Bonnaud, Laure; Botta, Giovanni; Cole, Alison; D'Angelo, Livia; De Girolamo, Paolo; Dennison, Ngaire; Dickel, Ludovic; Di Cosmo, Anna; Di Cristo, Carlo; Gestal, Camino; Fonseca, Rute; Grasso, Frank; Kristiansen, Tore; Kuba, Michael; Maffucci, Fulvio; Manciocco, Arianna; Mark, Felix Christopher; Melillo, Daniela; Osório, Daniel; Palumbo, Anna; Perkins, Kerry; Ponte, Giovanna; Raspa, Marcello; Shashar, Nadav; Smith, Jane; Smith, David; Sykes, António V.; Villanueva, Roger; Tublitz, Nathan; Zullo, Letizia; Andrews, PaulCephalopods have been utilised in neuroscience research for more than 100 years particularly because of their phenotypic plasticity, complex and centralised nervous system, tractability for studies of learning and cellular mechanisms of memory (e.g. long-term potentiation) and anatomical features facilitating physiological studies (e.g. squid giant axon and synapse). On 1 January 2013, research using any of the about 700 extant species of "live cephalopods" became regulated within the European Union by Directive 2010/63/EU on the "Protection of Animals used for Scientific Purposes", giving cephalopods the same EU legal protection as previously afforded only to vertebrates. The Directive has a number of implications, particularly for neuroscience research. These include: (1) projects will need justification, authorisation from local competent authorities, and be subject to review including a harm-benefit assessment and adherence to the 3Rs principles (Replacement, Refinement and Reduction). (2) To support project evaluation and compliance with the new EU law, guidelines specific to cephalopods will need to be developed, covering capture, transport, handling, housing, care, maintenance, health monitoring, humane anaesthesia, analgesia and euthanasia. (3) Objective criteria need to be developed to identify signs of pain, suffering, distress and lasting harm particularly in the context of their induction by an experimental procedure. Despite diversity of views existing on some of these topics, this paper reviews the above topics and describes the approaches being taken by the cephalopod research community (represented by the authorship) to produce "guidelines" and the potential contribution of neuroscience research to cephalopod welfare.
- Geochemical characteristics of sediments along the margins of an atlantic-mediterranean estuary (the Guadiana, Southeast Portugal): spatial and seasonal variationsPublication . Camacho, Sarita; Moura, Delminda; Connor, Simon; Boski, T.; Gomes, AnaThe present work describes spatial and seasonal variability in grain-size, pH and elemental characteristics (TOC, TIC, TN and C/N) in superficial sediments, as well as salinity, temperature and oxygen in the water, within the intertidal range of the Guadiana Estuary, SW Iberian Peninsula, during the year 2010. The results indicate that environmental parameters in the estuary are strongly dependent on spatial patterns, which reflect seasonal oscillations in freshwater discharge. The sediment is generally poorly sorted, with a symmetrical to very finely skewed distribution, in accordance with the low-energy conditions typical of the deposition areas. During winter, heavy rains forced the continuous discharge of Europe’s largest reservoir, the Alqueva dam, creating exceptional hydrodynamic conditions and causing coarser sediment deposition in the estuary. High marsh areas are controlled by flood tides, promoting vertical accretion of muddy sediments, especially silts. The lower areas of the saltmarsh and-mud flat areas are controlled by the ebb, with more efficient export of fines toward the platform and retention of sands, sometimes with significant amounts of bioclasts. In winter (average Q = 654 m3 s -1), salinity remained low throughout the estuary with the highest values (< 3) recorded up to 3 km inland from the river mouth, except in the most confined environments subject to greater evaporation. In summer (average Q = 52 m3 s -1), the estuarine waters are better mixed and significant saltwater intrusion extends approximately 8 km inland. The seasonal variation in surface water temperature was very high, with a difference of ca 14 º C in the maximum temperature recorded in winter and summer. A clear relationship between elevation (in relation to mean sea level) and organic matter, pH and particle size was observed. In the higher areas of the marsh, where the hydrodynamics is attenuated, differential deposition of fine sediments promotes organic matter entrapment and low pH. Sedimentary organic matter derives from a mixture of native aquatic and terrestrial sources. The mid-upper estuary areas and higher zones of the saltmarsh in the lower estuary incorporate a greater terrestrial component, whereas the low-middle marsh areas of the lower estuary experience a substantial contribution from indigenous aquatic sources. The present data help to understand the present environmental condition of the Guadiana Estuary and contribute baseline data for future climatic and environmental management studies based on sediment-dependent proxies
- Remark to the paper of S. Samko, "A note on Riesz fractional integrals in the limiting case alpha(x)p(x) equivalent to n", from FCAA, vol. 16, No 2, 2013Publication . Samko, StefanWe improve the formulation of the main statement in the paper "Note on Riesz fractional integrals in the limiting case alpha(x)p(x) equivalent to n", published in this journal, Fract. Calc. Appl. Anal., Vol. 16, No 2 (2013), DOI: 10.2478/s13540-013-0023-x; http://link.springer.com/article/10.2478/s13540-013-0023-x.
- Genetic Divergence for the Amphibian Pleurodeles waltl in Southwest Portugal: Dispersal Barriers Shaping Geographic PatternsPublication . Van Vliet, Mirjam; Diekmann, Onno; Machado, Margarida; Beebee, Trevor J. C.; Beja, Pedro; Serrao, Ester A.Dispersal and vicariance are the principal mechanisms responsible for the formation of biogeographic patterns, driven or maintained by the role of past and current barriers to dispersal. Southwest Portugal harbors a rich endemic fauna and flora where strongly differentiated taxa can be observed, suggesting ancient isolating mechanisms acted in this region. In this study, we used information from two partial mitochondrial sequences, combined with information from microsatellite loci and amplification success, to investigate biogeographic patterns of genetic divergence in populations of Pleurodeles waltl in Portugal. Our results demonstrate genetic differentiation at different time frames creating distinct populations in southwest Portugal, which might have arisen following isolation by a large river estuary and mountainous barriers. Habitat destruction associated with agricultural intensification raises conservation concerns over the unique biodiversity in this region.
- Oestradiol and prostaglandin F2 alpha regulate sexual displays in females of a sex-role reversed fishPublication . Gonçalves, David; Costa, Silvia Santos; Teles, Magda C.; Silva, Helena; Inglês, Mafalda; Oliveira, Rui F.The mechanisms regulating sexual behaviours in female vertebrates are still poorly understood, mainly because in most species sexual displays in females are more subtle and less frequent than displays in males. In a sex-role reversed population of a teleost fish, the peacock blenny Salaria pavo, an external fertilizer, females are the courting sex and their sexual displays are conspicuous and unambiguous. We took advantage of this to investigate the role of ovarian-synthesized hormones in the induction of sexual displays in females. In particular, the effects of the sex steroids oestradiol (E2) and testosterone (T) and of the prostaglandin F2 alpha (PGF2 alpha) were tested. Females were ovariectomized and their sexual behaviour tested 7 days (sex steroids and PGF2 alpha) and 14 days (sex steroids) after ovariectomy by presenting females to an established nesting male. Ovariectomy reduced the expression of sexual behaviours, although a significant proportion of females still courted the male 14 days after the ovary removal. Administration of PGF2 alpha to ovariectomized females recovered the frequency of approaches to the male's nest and of courtship displays towards the nesting male. However, E2 also had a positive effect on sexual behaviour, particularly on the frequency of approaches to the male's nest. T administration failed to recover sexual behaviours in ovariectomized females. These results suggest that the increase in E2 levels postulated to occur during the breeding season facilitates female mate-searching and assessment behaviours, whereas PGF2 alpha acts as a short-latency endogenous signal informing the brain that oocytes are mature and ready to be spawned. In the light of these results, the classical view for female fishes, that sex steroids maintain sexual behaviour in internal fertilizers and that prostaglandins activate spawning behaviours in external fertilizers, needs to be reviewed.
- Effects of non-steroidal anti-inflammatory drug (NSAID) diclofenac exposure in mussel Mytilus galloprovincialisPublication . Gonzalez-Rey, Maria; Bebianno, Maria JoãoIn recent years, research studies have increasingly focused on assessing the occurrence of active pharmaceutical ingredients (APIs) in ecosystems. However, much remains unknown concerning the potential effects on APIs on non-target organisms due to the complexity of the mode of action, reactivity and bioconcentration potential for each specific drug. The non-steroidal anti-inflammatory drug (NSAID) diclofenac (DCF) is one of the most frequently detected APIs in surface waters worldwide and has recently been included in the list of priority substances under the European Commission. In this study, mussels (Mytilus galloprovincialis) were exposed to an environmentally relevant nominal concentration of DCF (250 ng L(-1)) over 15 days. The responses of several biomarkers were assessed in the mussel tissues: condition index (CI); superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and phase II glutathione-S-transferase (GST) activities, lipid peroxidation levels (LPO) associated with oxidative stress, acetylcholinesterase (AChE) activity related to neurotoxic effects and vitellogenin-like proteins linked to endocrine disruption. This study demonstrated significant induction of SOD and GR activities in the gills in addition to high CAT activity and LPO levels in the digestive gland. Phase II GST remained unaltered in both tissues, while the up-regulation of the AChE activity was directly related to the vitellogenin-like protein levels in exposed females, indicating an alteration in the estrogenic activity, rather than a breakdown in cholinergic neurotransmission function. This study confirmed that DCF at a concentration often observed in surface water induces tissue-specific biomarker responses. Finally, this study also revealed the importance of a multi-biomarker approach when assessing the potentially deleterious effects in a species that may be vulnerable to the continuously discharge of APIs into the ecosystems; this approach provides crucial new information regarding the unknown effects of DCF.