First report of ciguatoxins in two starfish species : Ophidiaster ophidianus and Marthasterias glacialis

Ciguatera fish poisoning (CFP) is a syndrome caused by the ingestion of fish contaminated with Ciguatoxins (CTXs). These phycotoxins are produced mainly by dinoflagellates that belong to the genus Gambierdiscus that are transformed in more toxic forms in predatory fish guts, and are more present in the Indo-Pacific and Caribbean areas. It is estimated that CFP causes per year more than 10,000 intoxications worldwide. With the rise of water temperature and anthropogenic intervention, it is important to study the prevalence of CFP in more temperate waters. Through inter- and subtidal sampling, 22 species of organisms were collected, in Madeira and Azores archipelagos and in the northwestern Moroccan coast, during September of 2012 and June and July of 2013. A total of 94 samples of 22 different species of bivalves, gastropods, echinoderms and crustaceans where analyzed by Ultra Performance Liquid Chromatography-Mass Spectometry-Ion Trap-Time of Flight (UPLC-MS-IT-TOF) and Ultra Performance Chromatography- Mass Spectrometry (UPLC-MS). Our main aim was to detect new vectors and ascertain if there were some geographical differences. We detected for the first time putative CTXs in echinoderms, in two starfish species—M. glacialis and O. ophidianus. We detected differences regarding uptake values by organisms and geographical location. Toxin amounts were significant, showing the importance and the need for continuity of these studies to gain more knowledge about the prevalence of these toxins, in order to better access human health risk. In addition, we suggest monitoring of these toxins should be extended to other vectors, starfish being a good alternative for protecting and accessing human health risk.

Immune responses in Bathymodiolus azoricus upon Vibrio challenges : approaches to characterize mussel survival strategies and physiological adaptations in deep sea extreme environments

Tese de Doutoramento, Ciências do Mar, especialidade de Biologia Marinha, 18 de Dezembro de 2015, Universidade dos Açores.

Cytochrome c nitrite reductase from desulfovibrio desulfuricans ATCC 27774

The Journal of Biological Chemistry Vol. 278, No. 19, Issue of May 9, pp. 17455–17465, 2003

Bivalve taxonomic diversity throughout the Italian Pliocene as a tool for climatic-oceanographic and stratigraphic inferences

The state of research on the evolution of marine bivalve taxonomic diversity of the Mediterranean Pliocene is analysed. The following assertions are discussed: 1) The Early Pliocene malacofauna is characterized by a high number of warm-water taxa and a high taxonomic diversity with respect to that of the present time. 2) The first appreciable extinction event in the Mediterranean Pliocene approximates or just follows the FO of Globorotalia bononiensis. 3) The second appreciable extinction event is between the LAD of Discoaster tamalis and the LAD of Discoaster surculus . 4) A third minor extinction event is penecontemporaneous with the FO of Globorotalia inflaia. Taking into account the available data on the Pliocene extinction events it has been possible to distinguish 4 different molluscan units with different climatic-oceanographic significance.

Oysters return to the Tagus estuary through an ecological model

Dissertation submitted to the Faculty of Sciences and Technology of New University of Lisbon for obtaining the degree of Master in Environmental Management Systems

Assessment of eutrophication status of two Northern Irish Loughs

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia do Ambiente, perfil Engenharia Sanitária

Bivalve taxonomic diversity throughout the Italian Pliocene as a tool for climatic-oceanographic and stratigraphic inferences

The state of research on the evolution of marine bivalve taxonomic diversity of the Mediterranean Pliocene is analysed. The following assertions are discussed: 1) The Early Pliocene malacofauna is characterized by a high number of warm-water taxa and a high taxonomic diversity with respect to that of the present time. 2) The first appreciable extinction event in the Mediterranean Pliocene approximates or just follows the FO of Globorotalia bononiensis. 3) The second appreciable extinction event is between the LAD of Discoaster tamalis and the LAD of Discoaster surculus. 4) A third minor extinction event is penecontemporaneous with the FO of Globorotalia inflata. Taking into account the available data on the Pliocene extinction events it has been possible to distinguish 4 different molluscan units with different climatic-oceanographic significance.

Late Quaternary warm marine mollusks from Santa Maria (Azores); paleoecologic and paleobiogeographic considerations

The sub-fossil fauna from the Late Quaternary marine deposits of Santa Maria is made of more than 50 species of gastropods and bivalves, 19 of them collected recently and for the first time in the northern coast of the island (Lagoinhas Bay). The sub-fossil shells are found in deposits of beach sands, situated 2-3 meters above the present low tide. The carbonated sands from the basal part of the succession yield an autochthonous association of borers dominated by the bivalve Myoforceps aristata (Dillwin, 1817). Upwards, the marine sands contain concentrations of beach drift shells, including well-preserved supratidal and intertidal gastropods, among them a large number of Rissoidae. The bivalve fauna is dominated by disarticulated valves of Ervilia castanea (Montagu, 1803), a small infaunal coloniser of mobile sandy substrates. The composition of the fauna is made essentially of West European species, many of them common to the West Coast of Portugal. However, a few "warm guests" with West African or Caribbean affinities were also found, suggesting a close relation with some of the "Tyrrhenian" warm associations found in the Western Mediterranean.

Upper Paleocene-Early Eocene mollusks of Silveirinha (Figueira da Foz, West Central Portugal)

A collection of fossil gastropods and bivalves assembled at the Thanetian/Ypresian vertebrate site of Silveirinha (Figueira da Foz, West Central Portugal) is analysed from the point of view of systematics and palaeoecology. The diversity is scarce but the age and exceptional characteristics of the site are factors that substantiate a detailed study. The taxa identified are: Bithynia soaresi sp. nov., Gyraulus antunesi sp. nov., Chlamys sp. and Cardiiacea gen. sp. indet. The prevailing of freshwater gastropods and the occurrence of 2 fragments of marine bivalves suggest a palaeoenvironmental setting that is in conformity with interpretations already established, which are based both in sedimentologic and vertebrate data. These interpretations point out the existence of a freshwater environment opened from time to time to marine influences, resulting from a palaeoatlantic coast placed some kilometres westwards.

Modelação de organismos com crescimento logarítmico: aplicação às amonites *

This work refers to the development of modelling tools to create Ammonite shells in order to produce animated models for scientific dissemination and didactic purposes. In the approach here proposed we assume that the growth of those shells from an initial stage – the protoconch – can be interpreted as a succession of revolutions in turn of a central axis; thus the conch’s section will increase as a non-linear progression. So, we emphasise that the shape of many type of shells, e.g. gastropods and bivalves, is based on the equation of the logarithmic spiral deduced by R. Descartes. Pixels 3d (Pixels Digital Inc., 2005) is a TCL – scriptable modelling and animation software that allows extendable interapplication communication. Hence a standalone prototype (Shellia) with shell assignable parameters was produced and some of their issues and results will be presented here.

Light controlled synthesis of nucleic acids

Dissertação apresentada para obtenção do grau de Doutor em Bioquímica - especialidade Biotecnologia, pela Universidade Nova de Lisboa,Faculdade de Ciências e Tecnologia

Effects of storage, processing and proteolytic digestion on microcystin-LR concentration in edible clams

Accumulation of microcystin-LR (MC-LR) in edible aquatic organisms, particularly in bivalves, is widely documented. In this study, the effects of food storage and processing conditions on the free MC-LR concentration in clams (Corbicula fluminea) fed MC-LR-producing Microcystisaeruginosa (1 × 105 cell/mL) for four days, and the bioaccessibility of MC-LR after in vitro proteolytic digestion were investigated. The concentration of free MC-LR in clams decreased sequentially over the time with unrefrigerated and refrigerated storage and increased with freezing storage. Overall, cooking for short periods of time resulted in a significantly higher concentration (P < 0.05) of free MC-LR in clams, specifically microwave (MW) radiation treatment for 0.5 (57.5%) and 1 min (59%) and boiling treatment for 5 (163.4%) and 15 min (213.4%). The bioaccessibility of MC-LR after proteolytic digestion was reduced to 83%, potentially because of MC-LR degradation by pancreatic enzymes. Our results suggest that risk assessment based on direct comparison between MC-LR concentrations determined in raw food products and the tolerable daily intake (TDI) value set for the MC-LR might not be representative of true human exposure.

Análise do efeito da acidificação dos oceanos no desenvolvimento larvar de Crassostrea gigas

Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente – Perfil Engenharia Ecológica

Occurrence of Proteus mirabilis associated with two species of venezuelan oysters

The fecal contamination of raw seafood by indicators and opportunistic pathogenic microorganisms represents a public health concern. The objective of this study was to investigate the presence of enteric bacteria colonizing oysters collected from a Venezuelan touristic area. Oyster samples were collected at the northwestern coast of Venezuela and local salinity, pH, temperature, and dissolved oxygen of seawater were recorded. Total and fecal coliforms were measured for the assessment of the microbiological quality of water and oysters, using the Multiple Tube Fermentation technique. Analyses were made using cultures and 16S rRNA gene sequencing. Diverse enrichment and selective culture methods were used to isolate enteric bacteria. We obtained pure cultures of Gram-negative straight rods with fimbriae from Isognomon alatus and Crassostrea rhizophorae. Our results show that P. mirabilis was predominant under our culture conditions. We confirmed the identity of the cultures by biochemical tests, 16S rRNA gene sequencing, and data analysis. Other enterobacteria such as Escherichia coli, Morganella morganii and Klebsiella pneumoniae were also isolated from seawater and oysters. The presence of pathogenic bacteria in oysters could have serious epidemiological implications and a potential human health risk associated with consumption of raw seafood.

Alergia a Perceves no Contexto da Síndrome Ácaros-Crustáceos-Moluscos-Baratas

Introdução: A tropomiosina dos invertebrados é o pan-alergénio que une crustáceos, moluscos, aracnídeos, insectos e parasitas, encontrando-se significativa homologia de sequência entre as proteínas dos vários grupos. Os perceves são um tipo de crustáceo particularmente apreciado e consumido no nosso país; no entanto, a alergia a este crustáceo é uma situação bastante rara da qual só existe um trabalho publicado na literatura. Caso clínico: Apresentamos o caso de uma criança do sexo masculino, de 9 anos de idade, com asma brônquica, rinoconjuntivite alérgica e eczema atópico, sensibilizada a ácaros e baratas. Aos 7 anos, 10 minutos após a primeira ingestão de perceves, refere síndrome de alergia oral, angioedema periorbitário e rinoconjuntivite. Aos 8 anos, ocorreram 4 episódios semelhantes após ingestão de caracol, camarão, lula e choco (referindo ingestão prévia destes alimentos sem queixas). Aos 9 anos, refere episódio de urticária da face e angioedema periorbitário com inalação de vapores de cozedura de camarão. Foram realizados testes cutâneos por prick que se revelaram positivos para perceves, camarão, caracol, lula, choco, polvo e amêijoa em natureza, e para gamba, caranguejo e mexilhão com extractos comerciais. Os doseamentos de IgE específica sérica revelaram-se positivos para camarão, caracol, lula, polvo e amêijoa, bem como para perceves e tropomiosina recombinante. Foi efectuado SDS-PAGE immunoblotting com extracto de perceves que revelou várias fracções alergénicas com grande variação de pesos moleculares (19-88 kDa); foi ainda efectuado estudo de inibição com D. pteronyssinus, que inibiu várias fracções fixadoras de IgE no extracto de perceves. Discussão: Apresenta-se um caso raro de uma criança, com quadro de alergia respiratória associada a sensibilização a ácaros e baratas, com alergia alimentar a crustáceos –incluindo a perceves – e moluscos gastrópodes, bivalves e cefalópodes. Foram caracterizados os alergénios implicados na alergia a perceves e demonstrada a presença da tropomiosina como alergénio implicado, bem como a reactividade cruzada entre estes crustáceos e os ácaros.