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Diet-induced milk fat depression: Association with changes in milk fatty acid composition and fluidity of milk fat

GAMA, M. A. S.; GARNSWORTHY, P. C.; GRIINARI, J. M.; LEME, P. R.; RODRIGUES, P. H. M.; SOUZA, L. W. O.; LANNA, D. P. D.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
25.94%
This experiment was designed to examine changes in milk fatty acids during fish oil-induced milk fat depression (MFD) and to test the theory that these changes are related to milk fat fluidity. The experiment was divided into three periods: 1) Baseline: all cows (n = 12) received a high fiber diet without fish oil (FO) for 12 days; 2) Treatment: 4 cows/group received the following treatments for 21 days: a) Low fiber diet without FO (LF), b) High fiber diet+FO (HF+FO) and c) Low fiber diet+FO (LF+FO); 3) Post-treatment: cows returned to the baseline diet and were monitored for 12 days. FO was included at 1.6% DM and HF and LF diets had 40 and 26% NDF, respectively. Milk fat content and yield were unchanged by the LF diet, but were reduced by FO diets at both dietary fiber levels and recovered in the post-treatment period. FO diets caused a pronounced reduction in stearic and oleic acid concentrations in milk fat and an equally pronounced increase in trans-18:1 fatty acid concentrations. Milk fat mean melting point (MMP) was correlated with MFD (r=0.73) and with milk oleic acid concentration (r=-0.92). The ratio of oleic:stearic in milk fat increased gradually and consistently in response to FO. Trans-C18:1 isomers with double bounds at carbon :<= 10 increased with greater MFD and those with double bonds at carbon ! I I decreased with greater MFD. Trans-9 cis-11 CLA explained more than 80% of MFD and was strongly correlated with trans-10 C18:1. Maintenance of MMP below 39-40 degrees C suggests that the mammary gland was able to secrete only milk fat with adequate fluidity and that MFD could be an adaptation mechanism to prevent secretion of milk with higher MMP. (C) 2007 Elsevier B.V. All rights reserved.

Glomerular Nucleus of the Weakly Electric Fish, Gymnotus sp.: Cytoarchitecture, Histochemistry, and Fiber Connections-Insights from Neuroanatomy to Evolution and Behavior

GIASSI, Ana Catarina Casari; MALER, Leonard; MOREIRA, Jorge E.; HOFFMANN, Anette
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
35.76%
The present study provides a detailed description of morphological and hodological aspects of the glomerular nucleus in the weakly electric fish Gymnotus sp., and explores the evolutionary and functional implications flowing from this analysis. The glomerular nucleus of Gymnotus shows numerous morphological similarities with the glomerular nucleus of percomorph fish, although cytoarchitectonically simpler. In addition, congruence of the histochemical acetylcholinesterase (AChE) distribution with cytoarchitectonic data suggests that the glomerular nucleus, together with the ventromedial cell group of the medial subdivision of the preglomerular complex (PGm-vmc) rostrally, and the subglomerular nucleus (as identified by Maler et al. [1991] J Chem Neuroanat 4:1-38) caudally, may form a distinct longitudinally organized glomerular complex. Our results show that an important source of sensory afferents to the glomerular nucleus originates in the pretectal and electrosensorius nuclei. The glomerular nucleus in turn projects to the hypothalamus (inferior lobe and anterior hypothalamus), to the anterior tuberal nucleus, and to the medial region of the preglomerular nucleus (PGm). These data suggest that visual and electrosensory information reach the glomerular nucleus and are relayed to the hypothalamus and...

Desempenho, composição do leite e mecanismos envolvidos na depressão da gordura do leite (DGL) de vacas recebendo ácido linoléicos conjugados (CLA) e óleo de peixe na dieta.; Performance, milk composition and mechanisms involved in milk fat depression (MFD) of cows fed diets with conjugated linoleic acid (CLA) and fish oil.

Gama, Marco Antônio Sundfeld da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 26/08/2004 PT
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35.94%
A manipulação da dieta constitui uma prática efetiva e rápida de alteração da composição do leite, especialmente do seu teor de gordura. Entretanto, os mecanismos envolvidos não são ainda completamente conhecidos, embora muito se tenha avançado na última década. Sabe-se hoje que certo tipo de ácido graxo (CLA trans-10 cis-12) formado no rúmen sob condições específicas de alimentação é capaz de inibir a síntese de gordura do leite. Entretanto, depressão da gordura do leite (DGL) tem sido observada em casos (e.g. dietas contendo óleo de peixe) onde não há formação deste inibidor. Embora o efeito do CLA sobre a secreção de gordura do leite já esteja bem caracterizado, estudo prévio conduzido pelo nosso grupo mostrou ainda um aumento do teor de proteína do leite em resposta a este tratamento. Dois experimentos foram conduzidos com os seguintes objetivos principais, respectivamente: 1) determinar se um maior suprimento de proteína através da dieta afeta a secreção de proteína do leite de vacas recebendo CLA e 2) Estudar os mecanismos envolvidos na DGL de vacas recebendo dietas contendo óleo de peixe (OP) e níveis distintos de fibra. No primeiro experimento, 48 vacas em lactação receberam os seguintes tratamentos: 1) Dieta controle (DC) + Lac100...

Differential expression of myogenic regulatory factor MyoD in pacu skeletal muscle (Piaractus mesopotamicus Holmberg 1887: Serrasalminae, Characidae, Teleostei) during juvenile and adult growth phases

Alves de Almeida, Fernanda Losi; Carvalho, Robson Francisco; Pinhal, Danillo; Padovani, Carlos Roberto; Martins, Cesar; Dal Pai-Silva, Maeli
Fonte: Pergamon-Elsevier B.V. Ltd Publicador: Pergamon-Elsevier B.V. Ltd
Tipo: Artigo de Revista Científica Formato: 1306-1311
ENG
Relevância na Pesquisa
25.89%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 04/12756-3; Processo FAPESP: 05/56587-3; Skeletal muscle is the edible part of the fish. It grows by hypertrophy and hyperplasia, events regulated by differential expression of myogenic regulatory factors (MRFs). The study of muscle growth mechanisms in fish is very important in fish farming development. Pacu (Piaractus mesopotamicus) is one of the most important food species farmed in Brazil and has been extensively used in Brazilian aquaculture programs. The aim of this study was to analyze hyperplasia and hypertrophy and the MRF MyoD expression pattern in skeletal muscle of pacu (P. mesopotamicus) during juvenile and adult growth stages. Juvenile (n = 5) and adult (n = 5) fish were anaesthetized, sacrificed, and weight (g) and total length (cm) determined. White dorsal region muscle samples were collected and immersed in liquid nitrogen. Transverse sections (10 mu m thick) were stained with Haematoxilin-Eosin (HE) for morphological and morphometric analysis. Smallest fiber diameter from 100 muscle fibers per animal was calculated in each growth phase. These fibers were grouped into three classes (<20, 20-50, and >50 mu m) to evaluate hypertrophy and hyperplasia in white skeletal muscle. MyoD gene expression was determined by semi-quantitative RTPCR. PCR products were cloned and sequenced. juvenile and adult pacu skeletal muscle had similar morphology. The large number of <20 mu m diameter muscle fibers observed in juvenile fish confirms active hyperplasia. In adult fish...

Fish ladders select fish traits on migration - still a growing problem for natural fish populations

Volpato, Gilson Luiz; Barreto, Rodrigo Egydio; Marcondes, Ana Lucia; Andrade Moreira, Paula Sueli; de Barros Ferreira, Magali Fatima
Fonte: Taylor & Francis Ltd Publicador: Taylor & Francis Ltd
Tipo: Revisão Formato: 307-313
ENG
Relevância na Pesquisa
35.81%
We investigated the potential selective effect of fish ladders on physiological and morphological profiles of the curimbata, Prochilodus lineatus, during reproductive migration in Brazil. We registered sex, body weight and length, plasma glucose, hepatosomatic and gonadosomatic indices (HSI and GSI, respectively), hematocrit, leucocrit, blood cell and nucleus areas, and the diameter of white and red muscle fibers in fish sampled at the bottom (downstream) and at the top (upstream) of a fish ladder at a hydroelectric dam. Males and females at the top of the ladder showed higher size (weight and length), white muscle fiber diameters, plasma glucose levels and lower hematocrit when compared with those at the bottom. These size and muscle traits assist fish to overcome the ladder barrier and bypass the dam, an effort that might be reflected in the glucose levels. Females also showed higher GSI at the top of the fish ladder, a trait possibly facilitating their reproduction upstream. These results indicate that a dam system favors fish with specific morphological-physiological profile. This may have a strong influence upon upstream fish populations over generations and implies the presence of artificial selective pressure.

Muscle growth in Nile tilapia (Oreochromis niloticus): histochemical, ultrastructural and morphometric study

Dal Pai-Silva, M.; Carvalho, R. F.; Pellizzon, C. H.; Dal Pai, V
Fonte: Churchill Livingstone Publicador: Churchill Livingstone
Tipo: Artigo de Revista Científica Formato: 179-187
ENG
Relevância na Pesquisa
35.75%
Muscle growth in Nile tilapia (Oreochromis niloticus) was studied focusing on histochemical, ultrastructural, and morphometric characteristics of muscle fibers. Based on body length (cm), we studied four groups: G1 = 1.36+/-0.09, G2 = 3.38+/-0.44, G3 = 8.90+/-1.47, and G4 = 28.30+/-3.29 (mean+/-S.D.). All groups showed intense reaction to NADH-TR in subdermal fibers and weak or no reaction in deep layer fibers. In G3 and G4, an intermediate layer was also observed with fibers presenting weak reaction; in G4, groups of fibers with intense reaction were observed in the subdermal region. The myosin ATPase (m-ATPase) activities were acid-stable and alkali-labile in subdermal fibers; most deep layer fibers were alkali-stable and acid-labile. Intermediate fibers were acid-labile and alkali-stable. Two fiber populations were observed near deep muscle layer: one large presenting weak acid- and alkali-stable and the other small alkali-stable.During growth, muscle fiber hypertrophy was more evident in intermediate and white fibers for G3 and G4. However, in these groups, the presence of fiber diameters less than or equal to21 mum suggested that there is still substantial fiber recruitment, confirmed by ultrastructural study, but hypertrophy is the main mechanism contributing to increase in muscular mass. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

Histochemical study of muscle fiber types in Synbranchus marmoratus Bloch, 1795

Dal Pai-Silva, Maeli; Dal Pai, Vitalino; Da Mota, Diogenes Luiz; De Castro Rodrigues, Antonio
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 65-70
ENG
Relevância na Pesquisa
35.87%
The myotomal muscle of Synbranchus marmoratus was investigated using histochemical and immunohistochemical reactions. This musculature is composed of a superficial red compartment, uniformly distributed around the trunk circumferentially and also in the lateral line. The red compartment fibers are small in diameter and have an oxidative metabolism, a high rate of glycogen and a negative reaction to alkaline and acid myofibrillar ATPase (mATPase). The white muscle forms the bulk of the muscle mass. Its fibers are large in diameter and have a glycolytic metabolism, a negative reaction to glycogen, a strong reaction to alkaline mATPase and a negative reaction to acid mATPase. Between these two compartments there is an intermediate layer of fibers presenting a mosaic metabolism pattern with a high rate of glycogen. These fibers stained moderately for alkaline and acid m-ATPase. Several clusters of red muscles were observed inside the white muscle. Each cluster is composed of three fiber types, with a predominance of red and intermediate fibers. Reactivity to anti-MHC BA-D5 was positive only in the intermediate fibers. Reactivity to anti-MHC SC-71 was negative in all fiber types.

Digestibilidade e tempo de trânsito gastrintestinal de dietas contendo níveis crescentes de fibra bruta para pacu

Rodrigues, Laurindo André; El Hadi Perez Fabregat, Thiago; Fernandes, João Batista Kochenborger; Nascimento, Thiago Matias Torres; Sakomura, Nilva Kasue
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 169-173
POR
Relevância na Pesquisa
25.88%
This work aimed to evaluate the effect of increasing dietary fiber levels on the digestibility and gastrointestinal transit time (GTT) for pacu. The digestibility trial used 288 pacu in a completely randomized design, fed in aquaria and transferred to a modified Guelf-type feces collector, using the partial sampling method. The inert marker on the diets was chromic oxide (1%) to establish the diet digestibility. In the GTT assay, 288 pacu were distributed in 24 aquaria in a completely randomized design. Fish were fed with two colored diets - green and white - and feces color was determined after abdominal pressure. The white and green diets used 1% of titanium and chromic oxides, respectively. Total GTT was determined when all fish showed green feces. The apparent digestibility coefficients and GTT of diets decreased as dietary fiber levels increased. These results indicated that 9% dietary fiber can be used in pacu diets without negative effects on energy, protein, crude fiber and ether extract digestibility and GTT.

Expressão gênica de fatores que controlam o crescimento muscular do pacu (Piaractus mesopotamicus); Gene expression of factors that control the pacu (Piaractus mesopotamicus) skeletal muscle growth

Fernanda Losi Alves de Almeida
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 22/02/2011 PT
Relevância na Pesquisa
25.95%
Nos peixes, o crescimento muscular ocorre por hipertrofia e hiperplasia a partir da proliferação e diferenciação das células satélites, processos regulados pela expressão de fatores de transcrição e de crescimento. Os objetivos desse trabalho foram: (1) avaliar a morfologia, morfometria e expressão gênica da MyoD, miogenina e IGF-I na musculatura branca do pacu (Piaractus mesopotamicus) com 45, 90, 180, 400 dias pós-eclosão (dpe) e adultos (n=8) e (2) avaliar a expressão gênica da MyoD, miogenina e miostatina na musculatura branca e vermelha de pacus adultos (n=8). Em todos os grupos, fragmentos da musculatura branca foram dissecados e congelados em nitrogênio líquido. Nos adultos, também foram coletados fragmentos de músculo vermelho. Cortes histológicos (10 ?m) da musculatura branca, obtidos em criostato, foram corados com hematoxilina-eosina para avaliação da morfologia e morfometria. Em cada animal, foi determinado o menor diâmetro de 100 fibras musculares brancas que foram distribuídas em classes, na dependência do seu diâmetro (<20 ?m, 20-50 ?m, >50 ?m), para avaliar a hiperplasia e hipertrofia. A expressão gênica foi analisada por reação em cadeia da polimerase após transcrição reversa em tempo real. A morfologia da musculatura branca foi semelhante em todos os grupos. No grupo 45 dpe...

Toxicity of puffer fish: two species (Lagocephalus laevigatus, linaeus 1766 and Sphoeroides spengleri, Bloch 1785) from the Southeastern Brazilian coast

Oliveira,J. S.; Pires Junior,O. R.; Morales,R. A. V.; Bloch Junior,C.; Schwartz,C. A.; Freitas,J. C.
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2003 EN
Relevância na Pesquisa
35.72%
In Brazil, where puffer fish are considered poisonous, there are few documented cases on human consumption and consequent poisoning. In this study, toxicity of two puffer fish species from the Brazilian coast was examined. Specimens of Sphoeroides spengleri and Lagocephalus laevigatus were caught in São Sebastião Channel (North coast of São Paulo State, Brazil) between January 1996 and May 1997. Acidic ethanol extracts from muscle and skin plus viscera were tested for mice acute toxicity using the standard method of Kawabata. Polar extracts of S. spengleri showed high toxicity up to 946 MU/g. Extracts from L. laevigatus showed very low levels of toxicity, never exceeding 1.7 MU/g. All extracts from both species blocked amielinic nerve fiber evoked impulses of crustacean legs; this effect reverted on washing similar to the standard tetrodotoxin TTX. The aqueous extract solutions were partially purified using an ionic exchange column (Amberlit GC-50) followed by treatment with activated charcoal (Norit-A). The presence of TTX and their analogs in the semi-purified extracts were confirmed by HPLC and mass spectrometry (MALDI-TOF).

Fine mapping and DNA fiber FISH analysis locates the tobamovirus resistance gene L3 of Capsicum chinense in a 400-kb region of R-like genes cluster embedded in highly repetitive sequences

Tomita, R.; Murai, J.; Miura, Y.; Ishihara, H.; Liu, S.; Kubotera, Y.; Honda, A.; Hatta, R.; Kuroda, T.; Hamada, H.; Sakamoto, M.; Munemura, I.; Nunomura, O.; Ishikawa, K.; Genda, Y.; Kawasaki, S.; Suzuki, K.; Meksem, K.; Kobayashi, K.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
25.85%
The tobamovirus resistance gene L3 of Capsicum chinense was mapped using an intra-specific F2 population (2,016 individuals) of Capsicum annuum cultivars, into one of which had been introduced the C. chinenseL3 gene, and an inter-specific F2 population (3,391 individuals) between C. chinense and Capsicum frutescence. Analysis of a BAC library with an AFLP marker closely linked to L3-resistance revealed the presence of homologs of the tomato disease resistance gene I2. Partial or full-length coding sequences were cloned by degenerate PCR from 35 different pepper I2 homologs and 17 genetic markers were generated in the inter-specific combination. The L3 gene was mapped between I2 homolog marker IH1-04 and BAC-end marker 189D23M, and located within a region encompassing two different BAC contigs consisting of four and one clones, respectively. DNA fiber FISH analysis revealed that these two contigs are separated from each other by about 30 kb. DNA fiber FISH results and Southern blotting of the BAC clones suggested that the L3 locus-containing region is rich in highly repetitive sequences. Southern blot analysis indicated that the two BAC contigs contain more than ten copies of the I2 homologs. In contrast to the inter-specific F2 population...

Bioinformatics of Recent Aqua- and Orthoreovirus Isolates from Fish: Evolutionary Gain or Loss of FAST and Fiber Proteins and Taxonomic Implications

Nibert, Max L.; Duncan, Roy
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 04/07/2013 EN
Relevância na Pesquisa
25.95%
Family Reoviridae, subfamily Spinareovirinae, includes nine current genera. Two of these genera, Aquareovirus and Orthoreovirus, comprise members that are closely related and consistently share nine homologous proteins. Orthoreoviruses have 10 dsRNA genome segments and infect reptiles, birds, and mammals, whereas aquareoviruses have 11 dsRNA genome segments and infect fish. Recently, the first 10-segmented fish reovirus, piscine reovirus (PRV), has been identified and shown to be phylogenetically divergent from the 11-segmented viruses constituting genus Aquareovirus. We have recently extended results for PRV by showing that it does not encode a fusion-associated small transmembrane (FAST) protein, but does encode an outer-fiber protein containing a long N-terminal region of predicted α-helical coiled coil. Three recently characterized 11-segmented fish reoviruses, obtained from grass carp in China and sequenced in full, are also divergent from the viruses now constituting genus Aquareovirus, though not to the same extent as PRV. In the current study, we reexamined the sequences of these three recent isolates of grass carp reovirus (GCRV)–HZ08, GD108, and 104–for further clues to their evolution relative to other aqua- and orthoreoviruses. Structure-based fiber motifs in their encoded outer-fiber proteins were characterized...

High-resolution fish on DNA fibers for low-copy repeats genome architecture studies

Molina, O.; Blanco, J.; Anton, E.; Vidal, F.; Volpi, E.V.
Fonte: Academic Press Publicador: Academic Press
Tipo: Artigo de Revista Científica
Publicado em /12/2012 EN
Relevância na Pesquisa
25.88%
Low-copy repeats (LCRs) constitute 5% of the human genome. LCRs act as substrates for non-allelic homologous recombination (NAHR) leading to genomic structural variation. The aim of this study was to assess the potential of Fiber-FISH for LCRs direct visualization to support investigations of genome architecture within these challenging genomic regions. We describe a set of Fiber-FISH experiments designed for the study of the LCR22-2. This LCR is involved in recurrent reorganizations causing different genomic disorders. Four fosmid clones covering the entire length of the LCR22-2 and two single-copy BAC-clones, delimiting the LCR22-2 proximally and distally, were selected. The probes were hybridized in different multiple color combinations on DNA fibers from two karyotypically normal cell lines. We were able to identify three distinct structural haplotypes characterized by differences in copy-number and arrangement of the LCR22-2 genes and pseudogenes. Our results show that Multicolor Fiber-FISH is a viable methodological approach for the analysis of genome organization within complex LCR regions.

Systematic Application of DNA Fiber-FISH Technique in Cotton

Wang, Kai; Zhang, Wenpan; Jiang, Yanqin; Zhang, Tianzhen
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 27/09/2013 EN
Relevância na Pesquisa
25.96%
Fluorescence in situ hybridization on extended DNA (fiber-FISH) is a powerful tool in high-resolution physical mapping. To introduce this technique into cotton, we developed the technique and tested it by deliberately mapping of telomere and 5S rDNA. Results showed that telomere-length ranged from 0.80 kb to 37.86 kb in three species, G. hirsutum, G. herbaceum and G. arboreum. However, most of the telomeres (>91.0%) were below 10 kb. The length of 5S rDNA was revealed as 964 kb in G. herbaceum whereas, in G. arboreum, it was approximately three times longer (3.1 Mb). A fiber-FISH based immunofluorescence method was also described to assay the DNA methylation. Using this technique, we revealed that both telomere and 5S rDNA were methylated at different levels. In addition, we developed a BAC molecule-based fiber-FISH technique. Using this technique, we can precisely map BAC clones on each other and evaluated the size and location of overlapped regions. The development and application of fiber-FISH technique will facilitate high-resolution physical mapping and further directed sequencing projects for cotton.

Müller glia: Stem cells for generation and regeneration of retinal neurons in teleost fish

Lenkowski, Jenny R.; Raymond, Pamela A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
25.85%
Adult zebrafish generate new neurons in the brain and retina throughout life. Growth-related neurogenesis allows a vigorous regenerative response to damage, and fish can regenerate retinal neurons, including photoreceptors, and restore functional vision following photic, chemical, or mechanical destruction of the retina. Müller glial cells in fish function as radial-glial-like neural stem cells. During adult growth, Müller glial nuclei undergo sporadic, asymmetric, self-renewing mitotic divisions in the inner nuclear layer to generate a rod progenitor that migrates along the radial fiber of the Müller glia into the outer nuclear layer, proliferates, and differentiates exclusively into rod photoreceptors. When retinal neurons are destroyed, Müller glia in the immediate vicinity of the damage partially and transiently dedifferentiate, re-express retinal progenitor and stem cell markers, re-enter the cell cycle, undergo interkinetic nuclear migration (characteristic of neuroepithelial cells), and divide once in an asymmetric, self-renewing division to generate a retinal progenitor. This daughter cell proliferates rapidly to form a compact neurogenic cluster surrounding the Müller glia; these multipotent retinal progenitors then migrate along the radial fiber to the appropriate lamina to replace missing retinal neurons. Some aspects of the injury-response in fish Müller glia resemble gliosis as observed in mammals...

Bioinformatics of Recent Aqua- and Orthoreovirus Isolates from Fish: Evolutionary Gain or Loss of FAST and Fiber Proteins and Taxonomic Implications

Nibert, Max L.; Duncan, Roy
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
25.95%
Family Reoviridae, subfamily Spinareovirinae, includes nine current genera. Two of these genera, Aquareovirus and Orthoreovirus, comprise members that are closely related and consistently share nine homologous proteins. Orthoreoviruses have 10 dsRNA genome segments and infect reptiles, birds, and mammals, whereas aquareoviruses have 11 dsRNA genome segments and infect fish. Recently, the first 10-segmented fish reovirus, piscine reovirus (PRV), has been identified and shown to be phylogenetically divergent from the 11-segmented viruses constituting genus Aquareovirus. We have recently extended results for PRV by showing that it does not encode a fusion-associated small transmembrane (FAST) protein, but does encode an outer-fiber protein containing a long N-terminal region of predicted α-helical coiled coil. Three recently characterized 11-segmented fish reoviruses, obtained from grass carp in China and sequenced in full, are also divergent from the viruses now constituting genus Aquareovirus, though not to the same extent as PRV. In the current study, we reexamined the sequences of these three recent isolates of grass carp reovirus (GCRV)–HZ08, GD108, and 104–for further clues to their evolution relative to other aqua- and orthoreoviruses. Structure-based fiber motifs in their encoded outer-fiber proteins were characterized...

Effects of dietary fish oil and fibre on contractility of gut smooth muscle.

Patten, Glen Stephen
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2008
Relevância na Pesquisa
35.83%
From animal experimentation, and studies using in vitro models, there was evidence in the literature to suggest that dietary fibre may influence contractility and motility of the gastrointestinal tract and long chain (LC) n-3 polyunsaturated fatty acids (PUFAs) from marine sources may influence contractility of smooth muscle cells in blood vessels. The hypothesis of this thesis was that dietary fish oil and/or fibre influence the contractility of isolated intact sections of gut smooth muscle tissue from small animal models. Methodology was established to measure in vitro contractility of intact pieces of guinea pig ileum with the serosal side isolated from the lumen. It was demonstrated that four amino acid peptides from κ-casein (casoxins) applied to the lumen overcame morphine-induced inhibition of contraction. Using this established technology, the guinea pig was used to investigate the effects of dietary fibre and fish oil supplementation on gut in vitro contractility. In separate experiments, changes in sensitivity to electrically-driven and 8-iso-prostanglandin (PG)E₂-induced contractility were demonstrated for dietary fibre and fish oil. A modified, isolated gut super-perfusion system was then established for the rat to validate these findings. It was subsequently shown that LC n-3 PUFA from dietary fish oil significantly increased maximal contraction in response to the G-protein coupled receptor modulators...

Wheat fiber as a functional ingredient in restructured fish products

Sánchez Alonso, Isabel; Haji-Maleki, Ramin; Borderías, A. Javier
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 131381 bytes; application/pdf
ENG
Relevância na Pesquisa
35.97%
7 pages, 5 tables.-- Available online Jan 4, 2006.; The technological effect of wheat fiber as an ingredient in minced fish was tested. Thus 3% and 6% of wheat fiber with different size particles were added to minced hake (Merluccius merluccius) and horse mackerel (Trachurus trachurus) muscle and water was also added to maintain the original moisture of the sample. The addition of fiber increased the water holding capacity (WHC). The water binding capacity (WBC) also increased, but only when water was not added to maintain the moisture constant. The cooking drip was lower when 3% or 6% of fiber was added. In general, when the drip was released by gravity, the 250 μm particle fiber bound more water than the 80 μm particle fiber, but when the water was extracted by a centrifugal force the opposite was observed. Restructured products with fiber were whiter and their rigidity and cohesiveness were lower. Products with 3% of fiber were well rated by the sensory panel, unlike the products with 6% of fiber. No unusual flavors were apparent when the wheat fiber was added. The effect of fiber as a stabilizing agent on protein and lipid was not apparent, either.; This work has been supported by the Spanish Ministerio de Educación y Ciencia under Project AGL2002-04104-C04-03 and by UE under Integrated Project SEAFOODplus (Ref. FP6/506359). The authors thank the Spanish Ministerio de Educación y Ciencia for Ms. Sánchez-Alonso predoctoral fellowship.; Peer reviewed

Inhibition of hemoglobin-mediated oxidation of regular and lipid-fortified washed cod mince by a white grape dietary fiber

Sánchez Alonso, Isabel; Borderías, A. Javier; Larsson, Karin; Undeland, Ingrid
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artículo Formato: 110624 bytes; application/pdf
ENG
Relevância na Pesquisa
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7 pages, 2 figures.-- PMID: 17547416 [PubMed].-- Printed version published Jun 27, 2007.; The effectiveness of a white grape dietary fiber concentrate (WGDF) against hemoglobin-mediated oxidation of washed cod mince, with and without 10% added herring oil, was evaluated during ice storage. WGDF was added at two different levels: 2 and 4% based on final weight. An ethanol extract with the ethanol extractable polyphenols (EPP) and the ethanol-extracted grape dietary fiber residue were also tested as antioxidants in the washed cod mince. The addition of WGDF to the model system completely and significantly (p ≤ 0.05) inhibited the hemoglobin-mediated development of rancid odor during the entire ice storage (10 days). Thiobarbituric acid reactive substances (TBARS) development and red color (a*) losses supported the sensory data. Controls fortified with 10% herring oil oxidized at the same rate as oil-free controls and were also significantly stabilized by 2% WGDF. The EEP of the WGDF had the same high antioxidant capacity as whole WGDF. The ethanol-extracted fiber residue significantly (p ≤ 0.05) reduced maximum oxidation values obtained for controls by ~50% and extended the oxidation lag phase by 1 day (p ≤ 0.05). Thus, this study showed great potential of WGDF to prevent rancidity in fish...

Physical study of minced fish muscle with a white-grape by-product added as an ingredient

Sánchez Alonso, Isabel; Solas, M. Teresa; Borderías, A. Javier
Fonte: Blackwell Publishing Publicador: Blackwell Publishing
Tipo: Artículo Formato: 2259307 bytes; application/pdf
ENG
Relevância na Pesquisa
35.85%
8 pages, 4 figures, 3 tables.-- PMID: 17995839 [PubMed].; Functional properties of a white grape dietary fiber concentrate (WGDF) obtained from wine industry residues were determined with a view to their use as potential functional ingredient in seafood products. The main features of interest of WGDF are that it is a natural product containing high concentrations of dietary fiber (DF) with a high-soluble DF (sDF)/insoluble DF (iDF) ratio and associated bioactive compounds; as such it is considered potentially suitable for use as dietary fiber in the enrichment of foods. WGDF was therefore added to minced fish muscle (MFM) of horse mackerel (Trachurus trachurus) to take advantage of its technological properties, and also to enrich a food product that is a functional product in itself but does not contain dietary fiber. WGDF was added (2% and 4%) to MFM, which was stored for 6 mo at –20°C, and a further lot was vacuum packed. Physical and mechanical properties, sensory and color analyses, microscopy, and electrophoretic profiles were all done in samples every month. The results indicate that WGDF had good functional properties, high water and oil retention capacity, and considerable swelling properties, which would make it useful as a natural ingredient in foods. The addition of WGDF to MFM augmented aggregation of myofibrillar proteins in the course of frozen storage...