990 resultados para 670103 Fish products


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A myxosporean parasite in the gill lamellae of the freshwater teleost fish, Sciades herzbergii (Ariidae) (Block, 1794), from the Poti River (Northeast of Brazil) was described by light and electron microscopy studies. Polysporic histozoic cyst-like plasmodia containing several life-cycle stages, including mature spores, were observed. The spores were pyriform and uninucleate, measuring 9.15 ± 0.39 μm (n = 50) long, 4.36 ± 0.23 μm (n = 25) wide and 2.61 ± 0.31 μm (n = 25) thick. Elongated pyriform polar capsules (PC) were of equal size (4.44 ± 0.41 μm long and 1.41 ± 0.42 μm in diameter) and each contained a polar filament with 9-10 coils obliquely arranged in relation to the axis of PC. The PC wall was composed of two layers of different electron densities. Histological analysis revealed the close contact of the cyst-like plasmodia with the basal portion of the epithelial gill layer, which exhibited some alterations in the capillary vessels. Based on the morphological and ultrastructural differences, the similarity of the spore features to those of the genus Myxobolus and the specificity of this host to previously described species, we describe a new species named Myxobolus sciades n. sp. in this study.

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Résumé : Les mécanismes de sélection sexuelle, en particulier la compétition entre mâles (sélection inter-sexuelle) et le choix des femelles (sélection intra-sexuelle), peuvent fortement influencer le succès reproducteur d'un individu, c'est-à-dire son nombre de descendants. On observe ainsi que les mâles dominants et les mâles élaborant des caractères sexuels secondaires marqués ont un succès reproducteur élevé. Toutefois, le succès reproducteur ne suffit pas pour garantir une contribution génétique élevée, parce que la fitness dépend également de la performance des descendants (c'est-à-dire de leur survie et de leur propre succès reproducteur). Si cette performance dépend en partie des gènes paternels, les males ont un avantage certain à signaler leur qualité aux femelles afin d'atteindre des taux de reproduction élevé. Ce mécanisme de signalisation est connu sous le nom de 'good genes hypothesis', toutefois très peu d'études ont clairement démontré le lien entre la qualité génétique des individus et la signalisation. De plus, la performance des descendants peut aussi dépendre des effets génétiques de compatibilité entre mâles et femelles ('compatible genes'). C'est-à-dire que certains allèles paternels n'apporteraient un avantage aux descendants qu'en combinaison avec certains allèles maternels. Nous avons déterminé, durant la période de reproduction, le statut de dominance des mâles pour deux espèces de poissons d'eau douce : la truite (Salmo trotta) et le vairon (Phoxinus phoxinus), puis nous avons évalué la relation entre le succès reproducteur et le statut de dominance et/ou la quantité de signalisation des caractères sexuels secondaires. Nous avons également fécondés artificiellement des oeufs de truites et de corégones (Coregonus palaea), en croisant chaque mâle avec chaque femelle (full-factorial breeding design). Ce type de design autorise la quantification précise des effets génétiques et permet de séparer les effets de 'good genes' et de 'compatible genes'. Cela a été fait sous différentes intensités de stress bactérien, ainsi que dans des conditions naturelles, et nous avons pu ainsi tester si certains indicateurs de qualité génétique des mâles ('good genes') étaient liés a) à la dominance et/ou b) à l'expression des caractères sexuels secondaires des mâles comme l'intensité mélanique ou la taille des tubercules sexuels. En outre, nous cherchons à savoir si la survie des descendants est liée à certaines combinaison des gènes du complexe d'histocompatibilité majeur (MHC) et/ou à la parenté génétique des parents, les deux traits étant soupçonnés d'avoir des influences génétique de compatibilité (`compatible genes') à la performance des descendants. Nous avons constaté que la dominance des mâles est directement liée à la taille et au poids des mâles (truites, vairons), mais également aux caractères sexuels secondaires (tubercules). De plus, les mâles vairons dominant ont eu un succès de fécondation plus élevés que les mâles subordonnés. Nous montrons que les truites et corégones mâles diffèrent dans leur qualité génétique, qui a été mesurée avéc la survie embryonnaire, le temps avant l'éclosion et enfin la croissance juvénile. Contrairement aux prédictions, la dominance (ou les traits indicatifs de dominance) n'était liée à la qualité génétique, dans aucun des traitements, et ne fonctionne donc pas comme indicateur de qualité. Par contre, la qualité génétique était liée aux caractères sexuels secondaires, particulièrement par la teinte mélanique chez les truites. Les embryons de truites issus de pères sombres survivaient mieux que ceux issus de pères clairs dans des environnements difficiles, de plus leur croissance était plus élevée lors de leur première année dans des conditions naturelles. La taille des juvéniles lors de leur première année est un trait important lié au succès dans la compétition pour des ressources telles qu'abri ou nourriture. De plus, les femelles truites peuvent augmenter la survie de leurs descendants en choisissant des mâles selon leur type de MHC ou selon leur degré de parenté. En outre, chez les corégones, la morphologie des tubercules sexuels ne semble pas signaler la qualité génétique. Nous avons également remarqué que l'exposition à des pathogènes non-létaux pouvait influencer la performance des alevins à court et long terme, probablement en affaiblissant leur système immunitaire. Cette thèse montre que les mâles diffèrent dans leur qualité génétique et que différents mécanismes de sélection inter- ou intra-sexuelle (par exemple la préférence pour des mâles sombres, pour des génotypes MHC ou pour des couples avec degré de parenté basse) pouvait avoir un effet positif sur la qualité des descendants, bien que cet effet génétique pouvait changer au cours du temps et entre différents environnements. Contrairement à nos attentes, le résultat de la compétition intra-sexuelle (la hiérarchie de dominance entre mâles) n'était pas lié à la qualité génétique individuelle ('good genes'). Dans ce sens, ce travail permet également de contribuer à l'explication du fait que la sélection sexuelle, de par sa forte sélection directionnelle, ne conduit pas à la diminution de la variance génétique, mais plutôt à la maintenance du polymorphisme génétique. Summary : Sexual selection mechanisms, especially male-male competition (inteasexual selection) and female mate choice (inteasexual selection), can strongly influence individual mating success, often resulting in dominant males and males with elaborate secondary sexual characters having higher fertilisation success. However, siring a high number of offspring alone does not guarantee high individual fitness, as fitness does also strongly depend on offspring performance (i.e. survival, fecundity). If this superiority in offspring performance depends on paternally inherited genes, the fathers are expected to signal this potential indirect benefit to females in order to attain high mating rates. This mechanism is also known as the 'good genes' hypothesis of sexual selection but until now most studies failed to conclusively show the relation of an individual genetic quality and its potential signalling traits. Further, offspring performance could also depend on compatible gene effects. These are alleles that increase offspring performance only in combination with other specific alleles. We first determined male dominance status from intrasexual competition during mating season for brown trout (Salmo trutta) and European minnows (Phoxinus phoxinus). For minnows we additionally checked if dominance and/or secondary sexual traits were linked to fertilisation success. Further, we artificially fertilised brown trout and alpine whitefish (Coregonus palaea) eggs, following full factorial breeding designs, enabling to properly measure `good gene' and `compatible gene' effects on offspring performance. This was done under different intensities of natural stressors, as well as under natural conditions. This procedure allowed us to test if the obtained male genetic quality measures (good genes effects) were indicated by a) dominance or lay traits linked to dominance and/or by b) secondary sexual characteristics such as melanin-based male skin darkness or breeding tubercles. Further, we investigated if offspring survival was linked to the MHC (major histocompatibility complex) gene combinations and/or to the parental genetic relatedness, as both traits were shown to have 'compatible gene' effects that may influence offspring performance. We found that male dominance in intrasexual competition was positively linked to body size, body weight (brown trout, minnows) but also to elaborate secondary sexual characteristics (breeding tubercles in minnows). Further, dominant minnow males did have an increased fertilisation success compared to subordinate ones. We show that brown trout and whitefish males do usually differ in their genetic quality, which was measured as embryo survival, hatching timing and finally as juvenile growth. Contrary to prediction male dominance or dominance indicating traits do not function as a quality signal as they were not linked to genetic quality. This result was constant when measuring genetic quality under different levels of natural stressors and under natural conditions (brown trout). On the other hand genetic quality seemed to be indicated by secondary sexual characteristics, specifically by melanin-based skin darkness in brown trout as brown trout embryos sired by darker fathers had increased survival rates when raised under harsh conditions and. they grew larger as juveniles after one year of growth in a natural stream, which is an important trait influencing success of juveniles in competition for hidings, food and other resources. Furthermore, brown trout females may increase the survival of their embryos when choosing males according to their MHC genotypes or to the general genetic relatedness between themselves and their potential mates. In whitefish on the other hand breeding tubercle morphology did not seem to signal genetic quality. Eventually, we saw that anon-lethal exposure to pathogens might influence short term and long term offspring performance probably by weakening an exposed individual's immune system. This thesis shows that males usually differ in their genetic quality and that different inter- or intrasexual selection mechanisms (e.g. mate selection favouring dark males, preference for MHC genotype combinations or for unrelated mates) may have strong positive effects on genetically dependent offspring performance but that such genetìc effects can change over time and environments. In contrast to our a priori expectations, the outcome of intrasexual selection, namely male dominance hierarchies, with dominant males often having high fertilisation success, was not linked to individual genetic quality (`good genes'). In this sense the present thesis may also be a helpful contribution to understand why sexual selection does not lead to rapid loss of genetic variation by strong directional selection but could even lead to the maintenance of genetic variation in natural populations.

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Raphidascaris (Sprentascaris) lanfrediae sp. nov. is described from the intestine of the freshwater fish Satanoperca jurupari (Heckel) (Cichlidae) from the Guamá River, state of Pará, Brazil. The prevalence in fish (n = 59) was 27% with intensity of one-124 (mean 16) nematodes per fish. The new species is characterized mainly by the markedly larger size of ventricular appendix in relation to the oesophagus, presence of short male caudal alae, 14-16 subventral pairs of preanal papillae and six pairs of postanal papillae.

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Myxidium volitans sp. nov. (Myxozoa: Myxidiidae) parasitizing the hypertrophied green-brownish gallbladder of the teleost Dactylopterus volitans, collected in the Atlantic coast near Niterói, Brazil was described based on ultrastructural studies. The spores were fusiform, sometimes slightly crescent-shaped on average 21.7 ± 0.3 µm (mean ± standard deviation) (n = 50) long and 5.6 ± 0.4 µm (n = 30) wide. The spore wall was thin and smooth, comprising two equally-sized valves joined by a hardly visible sutural ridge. Spores containing two pyriform polar capsules (PC) (5.0 ± 0.4 × 2.3 ± 0.3 µm) (n = 30) are situated in each extremity of the spore. The PC wall was composed of hyaline layer (0.20-0.29 µm thick) and by a thin external granular layer. Each PC contains a polar filament (PF) with irregular arrangements that was projected from its apical region to the bases of PC and coiled laterally from bases to the tip of PC. Some regular striations and S-like structures in the periphery of the PFs with four-five irregular sections were observed. Based on the spore morphology, ultrastructural differences and the specificity of the host we describe this parasite as a new myxosporidian, named M. volitans sp. nov.

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BACKGROUND/OBJECTIVES Aging enhances frequency of chronic diseases like cardiovascular diseases or periodontitis. Here we reproduced an age-dependent model of the periodontium, a fully physiological approach to periodontal conditions, to evaluate the impact of dietary fat type on gingival tissue of young (6 months old) and old (24 months old) rats. METHODS/FINDINGS Animals were fed life-long on diets based on monounsaturated fatty acids (MUFA) as virgin olive oil, n-6 polyunsaturated fatty acids (n-6PUFA), as sunflower oil, or n-3PUFA, as fish oil. Age-related alveolar bone loss was higher in n-6PUFA fed rats, probably as a consequence of the ablation of the cell capacity to adapt to aging. Gene expression analysis suggests that MUFA or n-3PUFA allowed mitochondria to maintain an adequate turnover through induction of biogenesis, autophagy and the antioxidant systems, and avoiding mitochondrial electron transport system alterations. CONCLUSIONS The main finding is that the enhanced alveolar bone loss associated to age may be targeted by an appropriate dietary treatment. The mechanisms involved in this phenomenon are related with an ablation of the cell capacity to adapt to aging. Thus, MUFA or n-3PUFA might allow mitochondrial maintaining turnover through biogenesis or autophagy. They might also be able to induce the corresponding antioxidant systems to counteract age-related oxidative stress, and do not inhibit mitochondrial electron transport chain. From the nutritional and clinical point of view, it is noteworthy that the potential treatments to attenuate alveolar bone loss (a feature of periodontal disease) associated to age could be similar to some of the proposed for the prevention and treatment of cardiovascular diseases, a group of pathologies recently associated with age-related periodontitis.

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In this article we review first some of the possibilities in which the notions of Fo lner sequences and quasidiagonality have been applied to spectral approximation problems. We construct then a canonical Fo lner sequence for the crossed product of a concrete C* -algebra and a discrete amenable group. We apply our results to the rotation algebra (which contains interesting operators like almost Mathieu operators or periodic magnetic Schrödinger operators on graphs) and the C* -algebra generated by bounded Jacobi operators.

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This study examined whether the antidermatophytic activity of essential oils (EOs) can be used as an indicator for the discovery of active natural products against Leishmania amazonensis. The aerial parts of seven plants were hydrodistilled. Using broth microdilution techniques, the obtained EOs were tested against three strains of dermatophytes (Trichophyton mentagrophytes, Microsporum gypseum and Microsporum canis). To compare the EOs antifungal and antiparasitic effects, the EOs activities against axenic amastigotes of L. amazonensis were concurrently evaluated. For the most promising EOs, their antileishmanial activities against parasites infecting peritoneal macrophages of BALB/c mice were measured. The most interesting antifungal candidates were the EOs from Cymbopogon citratus, Otacanthus azureus and Protium heptaphyllum, whereas O. azureus, Piper hispidum and P. heptaphyllum EOs exhibited the lowest 50% inhibitory concentration (IC50) values against axenic amastigotes, thus revealing a certain correspondence between both activities. The P. hispidum EO was identified as the most promising product in the results from the infected macrophages model (IC50: 4.7 µg/mL, safety index: 8). The most abundant compounds found in this EO were sesquiterpenes, notably curzerene and furanodiene. Eventually, the evaluation of the antidermatophytic activity of EOs appears to be an efficient method for identifying new potential drugs for the treatment of L. amazonensis.

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Tumor-specific gene products, such as cancer/testis (CT) antigens, constitute promising targets for the development of T cell vaccines. Whereas CT antigens are frequently expressed in melanoma, their expression in colorectal cancers (CRC) remains poorly characterized. Here, we have studied the expression of the CT antigens MAGE-A3, MAGE-A4, MAGE-A10, NY-ESO-1 and SSX2 in CRC because of the presence of well-described HLA-A2-restricted epitopes in their sequences. Our analyses of 41 primary CRC and 14 metastatic liver lesions confirmed the low frequency of expression of these CT antigens. No increased expression frequencies were observed in metastatic tumors compared to primary tumors. Histological analyses of CRC samples revealed heterogeneous expression of individual CT antigens. Finally, evidence of a naturally acquired CT antigen-specific CD8(+) T cell response could be demonstrated. These results show that the expression of CT antigens in a subset of CRC patients induces readily detectable T cell responses.

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Introduction: There is little information regarding the impact of diet on disease incidence and mortality in Switzerland. Objectives: We aimed at assessing the associations between food availability and disease using ecological correlations. Methods: Time-trend ecologic study for period 1970 to 2009. Food availability was measured through the FAO food balance sheets. Standardized mortality rates (SMRs) were obtained from the Swiss Federal Office of Statistics. Cancer incidence data was obtained from the WHO Health for all database and the Vaud cancer registry. Association between food availability and mortality/incidence was assessed at lags 0, 5, 10 and 15 years by Spearman correlation. Results: Alcoholic beverages and fruit availability were positively associated with SMRs from all types of cardiovascular disease, while fish availability was negatively associated. Animal products, meat and animal fats were positively associated with SMR from ischemic heart disease only. For cancers, opposite results were found whether the association used SMRs or incidence rates. For all cancers, alcoholic beverages and fruits were positively associated with SMRs but negatively associated with incidence rates. Similar findings were obtained for all other foods, with the exception of vegetables, which were weakly and negatively associated with SMRs and incidence rates. Finally, a 15 years lag time reversed the association for animal and vegetal products, weakened the association for alcohol and fruits and strengthened the association for fish. Conclusion: Ecologic associations between food availability and disease vary considerably whether mortality or incidence rates are used. Great care should be taken when interpreting the results.

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Some people cannot buy products without first touching them, believing that doing so will create more assurance and information and reduce uncertainty. The international consumer marketing literature suggests an instrument to measure consumers' necessity for pohysical contact, called Need for Touch (NFT). This paper analyzes whether the Need for Touch structure is empirically consistent. Based on a literature review, we suggest six hypotheses in order to assess the nomological, convergent, and discriminant validity of the phenomenon. Departing from these, data supported four assumptions in the predicted direction. Need for Touch was associated with Need for Input and with Need for Cognition. Need for Touch was not associated with traditional marketing channels. The results also showed the dual characterization of Need for Touch as a bi-dimensional construct. The moderator effect indicated that when the consumer has a higher (vs. lower) Need for Touch autotelic score, the experiential motivation for shopping played a more (vs. less) important role in impulsive motivation. Our Study 3 supports the NFT structure and shows new associations with the need for unique products and dependent decisions.

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OBJECTIVE: Fish oil (FO) may attenuate the inflammatory response after major surgery such as abdominal aortic aneurysm (AAA) surgery. We aimed at evaluating the clinical impact and safety aspects of a FO containing parenteral nutrition (PN) after AAA surgery. METHODS: Intervention consisted in 4 days of either standard (STD: Lipofundin medium-chain triglyceride (MCT): long-chain triglyceride (LCT)50%-MCT50%) or FO containing PN (FO: Lipoplus: LCT40%-MCT50%-FO10%). Energy target were set at 1.3 times the preoperative resting energy expenditure by indirect calorimetry. Blood sampling on days 0, 2, 3 and 4. Glucose turnover by the (2)H(2)-glucose method. Muscle microdialysis. Clinical data: maximal daily T degrees, intensive care unit (ICU) and hospital stay. RESULTS: Both solutions were clinically well tolerated, without any differences in laboratory safety parameters, inflammatory, metabolic data, or in organ failures. Plasma tocopherol increased similarly; with FO, docosahexaenoic and eicosapentaenoic acid increased significantly by day 4 versus baseline or STD. To increased postoperatively, with a trend to lower values in FO group (P=0.09). After FO, a trend toward shorter ICU stay (1.6+/-0.4 versus 2.3+/-0.4), and hospital stay (9.9+/-2.4 versus 11.3+/-2.7 days: P=0.19) was observed. CONCLUSIONS: Both lipid emulsions were well tolerated. FO-PN enhanced the plasma n-3 polyunsaturated fatty acid content, and was associated with trends to lower body temperature and shorter length of stay.

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En aquesta memòria s'explica com, per la implantació de SAP en l'Hospital Universitari Arnau de Vilanova s'ha de realitzar una adequació tant de xarxa, com de parc d'ordinadors i impressores, instal·lació d'un nou cpd. Es fa un anàlisi previ de la situació i s'expliqen quins canvis es fan i perquè.

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Items purchased from Iowa Prison Industries for Iowa Departation of Transportation

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BACKGROUND: Transgressive segregation describes the occurrence of novel phenotypes in hybrids with extreme trait values not observed in either parental species. A previously experimentally untested prediction is that the amount of transgression increases with the genetic distance between hybridizing species. This follows from QTL studies suggesting that transgression is most commonly due to complementary gene action or epistasis, which become more frequent at larger genetic distances. This is because the number of QTLs fixed for alleles with opposing signs in different species should increase with time since speciation provided that speciation is not driven by disruptive selection. We measured the amount of transgression occurring in hybrids of cichlid fish bred from species pairs with gradually increasing genetic distances and varying phenotypic similarity. Transgression in multi-trait shape phenotypes was quantified using landmark-based geometric morphometric methods. RESULTS: We found that genetic distance explained 52% and 78% of the variation in transgression frequency in F1 and F2 hybrids, respectively. Confirming theoretical predictions, transgression when measured in F2 hybrids, increased linearly with genetic distance between hybridizing species. Phenotypic similarity of species on the other hand was not related to the amount of transgression. CONCLUSION: The commonness and ease with which novel phenotypes are produced in cichlid hybrids between unrelated species has important implications for the interaction of hybridization with adaptation and speciation. Hybridization may generate new genotypes with adaptive potential that did not reside as standing genetic variation in either parental population, potentially enhancing a population's responsiveness to selection. Our results make it conceivable that hybridization contributed to the rapid rates of phenotypic evolution in the large and rapid adaptive radiations of haplochromine cichlids.

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In hyperdiploid acute lymphoblastic leukaemia (ALL), the simultaneous occurrence of specific aneuploidies confers a more favourable outcome than hyperdiploidy alone. Interphase (I) FISH complements conventional cytogenetics (CC) through its sensitivity and ability to detect chromosome aberrations in non-dividing cells. To overcome the limits of manual I-FISH, we developed an automated four-colour I-FISH approach and assessed its ability to detect concurrent aneuploidies in ALL. I-FISH was performed using centromeric probes for chromosomes 4, 6, 10 and 17. Parameters established for automatic nucleus selection and signal detection were evaluated (3 controls). Cut-off values were determined (10 controls, 1000 nuclei/case). Combinations of aneuploidies were considered relevant when each aneuploidy was individually significant. Results obtained in 10 ALL patients (1500 nuclei/patient) were compared with those by CC. Various combinations of aneuploidies were identified. All clones detected by CC were observed by I-FISH. I-FISH revealed numerous additional abnormal clones, ranging between 0.1% and 31.6%, based on the large number of nuclei evaluated. Four-colour automated I-FISH permits the identification of concurrent aneuploidies of prognostic significance in hyperdiploid ALL. Large numbers of cells can be analysed rapidly by this method. Owing to its high sensitivity, the method provides a powerful tool for the detection of small abnormal clones at diagnosis and during follow up. Compared to CC, it generates a more detailed cytogenetic picture, the biological and clinical significance of which merits further evaluation. Once optimised for a given set of probes, the system can be easily adapted for other probe combinations.