49 research outputs found

    Diversity, environmental requirements, and biogeography of bivalve wood-borers (Teredinidae) in European coastal waters

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    Background: Bivalve teredinids inflict great destruction to wooden maritime structures. Yet no comprehensive study was ever carried out on these organisms in European coastal waters. Thus, the aims of this study were to: investigate the diversity of teredinids in European coastal waters; map their past and recent distributions to detect range expansion or contraction; determine salinity-temperature (S-T) requirements of species; flag, for future monitoring, the species that pose the greatest hazard for wooden structures. Results: A total of nine teredinid species were found established in European coastal waters. Seven were considered cryptogenic, of unknown origin, and two were considered alien species. Teredo navalis and Nototeredo norvagica were the species with the widest distribution in European waters. Recently, T. navalis has been reported occurring further east in the Baltic Sea but it was not found at a number of sites on the Atlantic coast of southern Europe. The Atlantic lineage of Lyrodus pedicellatus was the dominant teredinid in the southern Atlantic coast of Europe. In the Mediterranean six teredinid species occurred in sympatry, whereas only three of these occurred in the Black Sea. The species that pose the greatest hazard to wooden maritime structures in European coastal areas are T. navalis and the two lineages of L. pedicellatus. Conclusions: Combined data from field surveys and from the literature made it possible to determine the diversity of established teredinid species and their past and recent distribution in Europe. The environmental requirements of species, determined using climatic envelopes, produced valuable information that assisted on the explanation of species distribution. In addition, the observed trends of species range extension or contraction in Teredo navalis and in the two lineages of Lyrodus pedicellatus seem to emphasise the importance of temperature and salinity as determinants of the distribution of teredinids, whereas their life history strategy seems to play an important role on competition. Teredo navalis and pedicellatus-like Lyrodus species should be monitored due to their destructive capability. The two alien species may expand further their distribution range in Europe, becoming invasive, and should also be monitored.This research was partially funded by Fundação para a Ciência e a Tecnologia, Portugal through a personal grant to LB (SFRH/BD/17915/2004)

    New occurrences of Corallium spp. (Octocorallia, Coralliidae) in the Central Northeast Atlantic

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    Corallium niobe Bayer, 1964 and Corallium tricolor (Johnson, 1899) are reported as new records from the central Northeast Atlantic. C. niobe was caught in the Azores and C. tricolor on the slope of the Irving Seamount (South Azores Seamounts). The presence of Corallium johnsoni Gray, 1860 in Azorean waters is confirmed. The sub-tropical Macaronesian islands and seamounts appear to be an important hot-spot for Corallium spp. Most colonies have been collected on seamounts and island slopes around Madeira, Canaries, Azores and the Cape Verde archipelagos. In the Azores most of these corals live below the normal depth of commercial fishing operations and are unlikely to be severely impacted by this activity

    The Mauritanian Slope (NE Atlantic) Has No Desert: <em>Swiftia phaeton</em> (Holaxonia: Plexauridae) Shaping Coral Gardens

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    Swiftia Duchassaing & Michelotti, 1864, is often found sparse in the NE Atlantic Ocean and Mediterranean Sea. When the cruise MSM 16/3 “PHAETON” filmed the upper bathyal off Mauritania in 2010, the first dense populations dominated by Swiftia were discovered in the NE Atlantic Ocean, co-occurring with the framework-forming scleractinians Desmophyllum pertusum (Linnaeus, 1758) and Madrepora oculata Linnaeus, 1758. Remotely operated vehicle (ROV) video annotation from two canyons and two coral mounds considered Swiftia phaeton Sampaio, Beuck & Freiwald, 2022 presence, size class and abundance as well as substrate and geomorphology of the seafloor. Coral gardens definition included abundance and size of the species. Dense and very dense mono- and multispecific coral gardens dominated by S. phaeton were mapped between 20°24′N and 17°54′N in 470–640 m depth. The resilience of these coral gardens off Mauritania is mainly linked to the presence of hard substrate available to settle and to the exposition of currents rich in food. Still, these ecosystems are located inside a hydrocarbon exploration area off Mauritania and where fisheries occur since the 1960s. Sedimentation plumes caused by both activities can travel and impact on settlement, development, and survival of these populations. Hence, these vulnerable “oases” should be protected

    Comparative study between oral miltefosine and parenteral N-metil glucamine antimoniate for the treatment of experimental leishmaniasis caused Leishmania (Leishmania) amazonensis

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    Vinte e cinco camundongos infectados com Leishmania amazonensis foram tratados com antimoniato de N-metil glucamina e miltefosina oral. Critérios: medidas das patas, pesquisa de amastigotas e culturas após-tratamento. Miltefosina: 2,43mm e glucamina 3,46mm (p=0,05). Miltefosina: esfregaços e culturas negativos. Glucamina: 2 esfregaços positivos e culturas positivas (p<0,05). Concluímos que miltefosina foi semelhante à glucamina.Twenty-five mice were infected with Leishmania amazonensis and treated with glucamine and oral miltefosine. The criteria used were pad measurements and investigations of amastigotes and cultures after treatment. Measurements: miltefosine 2.43 mm and glucamine 3.46 mm (p: 0.05). Miltefosine smears and cultures were negative. Glucamine produced two positive smears and the cultures were positive (p < 0.05). Miltefosine was similar to or better than glucamine

    Zoantharians (Hexacorallia: Zoantharia) Associated with Cold-Water Corals in the Azores Region: New Species and Associations in the Deep Sea

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    Zoantharians are a group of cnidarians that are often found in association with marine invertebrates, including corals, in shallow and deep-sea environments. However, little is known about deep-sea zoantharian taxonomy, specificity and nature of their associations with their coral hosts. In this study, analyses of molecular data (mtDNA COI, 16S, and 12S rDNA) coupled with ecological and morphological characteristics were used to examine zoantharian specimens associated with cold-water corals (CWC) at depths between 110 and 800 m from seamounts and island slopes in the Azores region. The zoantharians examined were found living in association with stylasterids, antipatharians and octocorals. From the collected specimens, four new species were identified: (1) Epizoanthus martinsae sp. n. associated with the antipatharian Leiopathes sp.; (2) Parazoanthus aliceae sp. n. associated with the stylasterid Errina dabneyi (Pourtalès, 1871); (3) Zibrowius alberti sp. n. associated with octocorals of the family Primnoidae [Paracalyptrophora josephinae (Lindström, 1877)] and the family Plexauridae (Dentomuricea aff. meteor Grasshoff, 1977); (4) Hurlizoanthus hirondelleae sp. n. associated with the primnoid octocoral Candidella imbricata (Johnson, 1862). In addition, based on newly collected material, morphological and molecular data and phylogenic reconstruction, the zoantharian Isozoanthus primnoidus Carreiro-Silva, Braga-Henriques, Sampaio, de Matos, Porteiro &amp; Ocaña, 2011, associated with the primnoid octocoral Callogorgia verticillata (Pallas, 1766), was reclassified as Zibrowius primnoidus comb. nov. The zoantharians, Z. primnoidus comb. nov., Z. alberti sp. n., and H. hirondelleae sp. n. associated with octocorals showed evidence of a parasitic relationship, where the zoantharian progressively eliminates gorgonian tissue and uses the gorgonian axis for structure and support, and coral sclerites for protection. In contrast, the zoantharian P. aliceae sp. n. associated with the stylasterid E. dabneyi and the zoantharian E. martinsae sp. n. associated with the antipatharian Leiopathes sp., appear to use the coral host only as support with no visible damage to the host. The monophyly of octocoral-associated zoantharians suggests that substrate specificity is tightly linked to the evolution of zoantharians.Zibrowius alberti sp. n. urn:lsid:zoobank.org:act:8E186AD4-CA6E-419B-B46A-4C8D11C757DDHurlizoanthus hirondelleae sp. n. urn:lsid:zoobank.org:act:6737B10E-9E87-4BA0-9559-C22D49863732Parazoanthus aliceae sp.n. urn:lsid:zoobank.org:act:3D3AA61D-E5CC-47DF-94F1-A4A2FF59ABEAEpizoanthus martinsae sp. n. urn:lsid: zoobank.org:act:04686BB5-03D7-4132-B52B-CC89DF8EBFA8urn:lsid:zoobank.org:pub:FED88229-30F9-481F-9155-FF481790AE5

    Overview of Q fever in Brazil: an underestimated zoonosis

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    This review aims to provide current information about Q fever, elucidating the etiological, epidemiological, pathogenic, clinical, diagnostic, therapeutic, and prophylactic aspects of the disease for the medical community. We discuss the main forms of presentation of the agent, its ability to persist in the body, the infinite possibilities of susceptible hosts, the main known forms of transmission, its importance in populations at occupational risk, and the role of arthropods in the natural history of the disease. Focusing on Brazil, we present the cases already described and studies developed since its first report, and how there is still much to unravel. We are aware of the possibilities of the persistence of the agent and the development of severe clinical pictures and the specific treatments currently instituted. We also wish to raise awareness about the future, the new genotypes that are emerging, the need to study the effects of vaccines, and the impact of Q fever on the population. Q fever is a poorly understood disease in Latin America, and recent studies, especially in Brazil, have revealed the importance of developing new studies

    Utilização de enzimas industriais na avaliação da fibra insolúvel em detergente neutro em amostras com alto teor de amido

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    Foram realizados dois experimentos com o objetivo de avaliar o uso de enzimas industriais na avaliação da fibra em detergente neutro (FDN) de materiais ricos em amido. No primeiro experimento verificou-se a exatidão das estimativas dos teores de FDN obtidas com a utilização de diferentes enzimas industriais (Termamyl 2X, Liquozyme Supra 2.2X e Amylase AG 300L) em diferentes volumes (50, 100, 250 ou 500 µL/amostra). Foram produzidas amostras contendo amido nas concentrações de 0, 100, 300, 500 e 1000 g/kg, utilizando celulose e amido purificados (n = 240). No segundo experimento foram avaliadas amostras de milho e sorgo, considerando-se os três tipos e os quatro volumes de enzimas utilizados no primeiro experimento, sendo adicionada a avaliação de alíquotas sem a utilização de enzimas (n = 104). Para amostras simuladas com concentração de amido menor ou igual a 300 g/kg não foram verificados vícios significativos sobre a recuperação da FDN, não havendo diferenças entre enzimas. Houve redução mais acentuada do teor de FDN por volume de enzima na amostra de milho em comparação ao sorgo. Para a avaliação dos teores de fibra em detergente neutro recomenda-se o uso das α-amilases Termamyl 2X e Liquozyme 2.2X com atividades de 240 e 300 KNU/g, respectivamente, em volumes de 250 mL para amostras de massa variando de 0,7 a 1,0 g.It were performed two experiments to evaluate the utilization of industrial enzymes in the evaluation of NDF contents in high-starch materials. In the first experiment, it was verified the accuracy of estimates of neutral detergent fiber (NDF) obtained with the utilization of three industrial enzymes (Termamyl 2X, Liquozyme Supra 2.2.X, and Amylase AG 300L) at different volumes (50, 100, 250 or 500 mL/ sample). Samples were simulated to contain starch at 0, 100, 300, 500 and 1000 g/kg using purified cellulose and starch (n = 240). In the second experiment, samples of corn grain and sorghum grain were evaluated considering the same enzyme types and volumes used in the first experiment adding aliquots without using enzyme (n = 104). There was no significant bias of NDF recovery for simulated samples containing starch up to 300 g/kg. Considering those samples, none difference among enzymes was observed. It was observed a more intense decrease in NDF content according to each enzyme unit added on corn when compared to sorghum. Considering NDF evaluation in samples with mass of 0.7 to 1.0 g, it can be recommended the utilization of 250 mL the α-amylases Termamyl 2X and Liquozyme 2.2X with activities of 240 and 300 KNU/g, respectively

    Extracellular matrix in Staphylococcus epidermidis biofilms: a consequence of bacterial production or cell wall degradation?

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    Staphylococcus epidermidis is a leading pathogen accounting for nosocomial infections. The ability to form biofilms is considered the major virulence factor of this bacterium. The hallmark of this type of infection is the presence of an extracellular polymeric matrix that, in the case of S. epidermidis biofilms, is mainly constituted by an N-acetylglucosamine polymer. We have identified a subpopulation of bacteria that we believe to be the responsible for the extracellular matrix accumulation in S. epidermidis biofilms as they have comparative significant higher amount of surface N-acetylglucosamine. Flow cytometric evaluation of cell wall permeability and transmission electronic microscopy are highly suggestive of primary wall degradation in these bacteria. In overall, these results suggest that the extracellular matrix in S. epidermidis biofilms is a consequence of the degradation of the bacteria cell wall and that propide iodium should be used with care when used as a marker for bacteria dead in biofilms

    The use of açaí as a potential antioxidant for bovine semen cryopreservation

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    Semen cryopreservation is an important tool for animal reproduction due to its potential for fast dissemination of genetics from males with high genetic merit. However, cryopreservation protocols continue to provoke negative effects on sperm cell structure and function, thus leading to lower viability. This reduction in viability is correlated with excessive production of reactive oxygen species (ROS) that generate oxidative stress, which is responsible for lowering sperm motility, alteration in plasma membrane fluidity, and lipidic peroxidation. Due to these facts, it becomes necessary to add substances with the antioxidant potential for semen cryopreservation to confer additional protection to sperm cells. A variety of compounds from plants and fruits have been incorporated to such media due to their antioxidant potential. In such context, açaí has gained attention by researchers due to its substantial antioxidant capacity, particularly attributed to its polyphenolic fraction, which is rich in anthocyanins. Moreover, it also contains resveratrol and quercetin in its composition, which has activity against free radicals. In general terms, the antioxidant of natural sources (i.e., açaí) deserves special attention since it contributes to the preservation of the national flora, also displays a significant potential to improve the quality of frozen-thawed bovine semen
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