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851.
The Pacific jack Caranx caninus is a common species fished by artisanal fishermen off the coast of Colima, México. During 2002, monthly samples of morphometric data and otoliths were taken to determine age and growth. Seven age groups were identified. The highest growth, 14.4 cm, takes place during the first year of life. During the second year, C caninus grows 11.76 cm; the third year 9.61 cm; the fourth 7.85 cm; the fifth 6.41 cm and sixth year 5.24 cm. The constants of von Bertalanffy's growth equation were: L(infinity) = 83.26 cm, W(infinity) = 18.138 g, K = 0.202, t(0) = -0.283 and A(0.95) = 15 years. Growth curves of other species of the same genus were calculated in order to compare them with the one obtained in the present work. The gonadosomatic index presented higher values during November and May. The periods of more intensive feeding are from August to February. 相似文献
852.
Ivonne R. Blandon Francisco J. Garcia De Len Rocky Ward Ronald A. Van Den Bussche David S. Needleman 《Molecular ecology resources》2003,3(4):632-634
The tarpon, Megalops atlanticus, supports important recreational fisheries in the Atlantic Ocean, Caribbean Sea and Gulf of Mexico. Declines in segments of these fisheries have prompted questions concerning genetic stock structure in this species. Preparatory to a survey of genetic variation in tarpon, 15 microsatellite markers were isolated. The number of alleles per locus ranged from two to 10 and observed heterozygosity ranged from 0.091 to 0.765, providing potentially useful markers for the detection of within‐ and among‐population genetic variability. 相似文献
853.
Sabrina Florent-Béchard Cédric Desbène Pierre Garcia Ahmad Allouche Ihsen Youssef Marie-Christine Escanyé Violette Koziel Marine Hanse Catherine Malaplate-Armand Christophe Stenger Badreddine Kriem Frances T. Yen-Potin Jean Luc Olivier Thierry Pillot Thierry Oster 《Biochimie》2009
In the absence of efficient diagnostic and therapeutic tools, Alzheimer's disease (AD) is a major public health concern due to longer life expectancy in the Western countries. Although the precise cause of AD is still unknown, soluble β-amyloid (Aβ) oligomers are considered the proximate effectors of the synaptic injury and neuronal death occurring in the early stages of AD. Aβ oligomers may directly interact with the synaptic membrane, leading to impairment of synaptic functions and subsequent signalling pathways triggering neurodegeneration. Therefore, membrane structure and lipid status should be considered determinant factors in Aβ-oligomer-induced synaptic and cell injuries, and therefore AD progression. Numerous epidemiological studies have highlighted close relationships between AD incidence and dietary patterns. Among the nutritional factors involved, lipids significantly influence AD pathogenesis. It is likely that maintenance of adequate membrane lipid content could prevent the production of Aβ peptide as well as its deleterious effects upon its interaction with synaptic membrane, thereby protecting neurons from Aβ-induced neurodegeneration. As major constituents of neuronal lipids, n-3 polyunsaturated fatty acids are of particular interest in the prevention of AD valuable diet ingredients whose neuroprotective properties could be essential for designing preventive nutrition-based strategies. In this review, we discuss the functional relevance of neuronal membrane features with respect to susceptibility to Aβ oligomers and AD pathogenesis, as well as the prospective capacities of lipids to prevent or to delay the disease. 相似文献
854.
Matté C Mackedanz V Stefanello FM Scherer EB Andreazza AC Zanotto C Moro AM Garcia SC Gonçalves CA Erdtmann B Salvador M Wyse AT 《Neurochemistry international》2009,54(1):7-13
We have previously demonstrated that acute hyperhomocysteinemia induces oxidative stress in rat brain. In the present study, we initially investigated the effect of chronic hyperhomocysteinemia on some parameters of oxidative damage, namely total radical-trapping antioxidant potential and activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase), as well as on DNA damage in parietal cortex and blood of rats. We also evaluated the effect of folic acid on biochemical alterations elicited by hyperhomocysteinemia. Wistar rats received daily subcutaneous injection of Hcy (0.3-0.6 micromol/g body weight), and/or folic acid (0.011 micromol/g body weight) from their 6th to their 28th day of life. Twelve hours after the last injection the rats were sacrificed, parietal cortex and total blood was collected. Results showed that chronic homocysteine administration increased DNA damage, evaluated by comet assay, and disrupted antioxidant defenses (enzymatic and non-enzymatic) in parietal cortex and blood/plasma. Folic acid concurrent administration prevented homocysteine effects, possibly by its antioxidant and DNA stability maintenance properties. If confirmed in human beings, our results could propose that the supplementation of folic acid can be used as an adjuvant therapy in disorders that accumulate homocysteine. 相似文献
855.
Júlio César Bicca-Marques Carina Barboza Muhle Helissandra Mattjie Prates Sabine Garcia de Oliveira Cláudia Calegaro-Marques 《International journal of primatology》2009,30(5):743-748
Species response to habitat loss, fragmentation, or alteration ranges from intolerance and extinction to tolerance and population
growth. An ability to increase trophic niche breadth is likely to play a key role in promoting tolerance to habitat change
in many species. Howlers (Alouatta spp.) are good examples of these tolerant species. Researchers have related their capacity to thrive well in disturbed habitats
to their ability to exploit an eclectic vegetarian diet. Despite >50,000 h of observation of habituated free-ranging groups
throughout the distribution of Alouatta, no case of intentional ingestion of animal matter has ever been observed. Here, we report an unexpected trophic niche broadening
for free-ranging groups of black-and-gold howlers (Alouatta caraya) living in small (≤2 ha) impoverished habitat islands in the State of Rio Grande do Sul, Brazil. We studied 3 isolated social
groups (15–17, 12–14, and 5 individuals) and observed 1 of them preying on birds’ nests. We recorded 19 events of egg-eating
during 2274 h of observation in 1 group and 2 suspected cases in another. Our findings highlight the dietary flexibility that
characterize howlers and contrast with the widely held view that they observe a strictly vegetarian diet. 相似文献
856.
Peter Sogaard Ferenc Szekeres Maria Holmström Dennis Larsson Mikael Harlén Pablo Garcia‐Roves Alexander V. Chibalin 《Journal of cellular biochemistry》2009,107(6):1189-1197
In vitro incubation of isolated rodent skeletal muscle is a widely used procedure in metabolic research. One concern with this method is the development of an anoxic state during the incubation period that can cause muscle glycogen depletion. Our aim was to investigate whether in vitro incubation conditions influence glycogen concentration in glycolytic extensor digitorum longus (EDL) and oxidative soleus mouse muscle. Quantitative immunohistochemistry was applied to assess glycogen content in incubated skeletal muscle. Glycogen concentration was depleted, independent of insulin‐stimulation in the incubated skeletal muscle. The extent of glycogen depletion was correlated with the oxidative fibre distribution and with the induction of hypoxia‐induced‐factor‐1‐alpha. Insulin exposure partially prevented glycogen depletion in soleus, but not in EDL muscle, providing evidence that glucose diffusion is not a limiting step to maintain glycogen content. Our results provide evidence to suggest that the anoxic milieu and the intrinsic characteristics of the skeletal muscle fibre type play a major role in inducing glycogen depletion in during in vitro incubations. J. Cell. Biochem. 107: 1189–1197, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
857.
Raquel Garcia Petra Fousková Lurdes Gano António Paulo Paula Campello Éva Tóth Isabel Santos 《Journal of biological inorganic chemistry》2009,14(2):261-271
The novel DOTA-like chelator 1,4,7,10-tetraazacyclododecane-1-{4-[(3-chloro-4-fluorophenyl)amino]quinazoline-6-yl}propionamide-4,7,10-triacetic
acid (H3L) was synthesised by alkylation of 1,4,7,10-tetraazacyclododecane-1,4,7-tris(t-butyl acetate) with N-{4-[(3-chloro-4-fluorophenyl)amino]quinazoline-6-yl}-3-bromopropionamide, followed by hydrolysis of the ester groups with
trifluoracetic acid. H3L has been fully characterised by multinuclear NMR spectroscopy, mass spectrometry and high-performance liquid chromatography
(HPLC). Five protonation constants, log K
Hi
, of H3L were determined by potentiometry and UV–vis spectrophotometry and the values found are 10.47, 9.18, 5.24, 4.00 and 2.23.
These methods, complemented with variable-pH 71Ga NMR studies, allowed us to ascertain the stability constant of the Ga(III) complex of L. GaL has a remarkably high thermodynamic
stability constant (log K
ML = 24.5). The radioactive complex 67GaL was prepared in high yield and high radiochemical purity. Its HPLC chromatogram is identical to that obtained for the
GaL complex prepared at the macroscopic level. At pH 7.4, 67GaL has an overall neutral charge, is highly hydrophilic (log D = −1.02 ± 0.03) and presents high in vitro stability in physiological media and in the presence of an excess of diethylenetriaminepentaethanoic
acid . In vitro studies indicated that H3L and GaL do not inhibit the cell growth of epidermal growth factor receptor expressing cell lines, such as A431 cervical
carcinoma cells, a result which agrees with the very low cell internalisation found for 67GaL in the same cell line. Biodistribution studies in mice indicated high in vivo stability for 67GaL, a high total excretion rate and a relatively slow blood clearance, in full accordance with its hydrophilic character
and the relatively important protein binding.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
858.
Cunha AC Pereira RO Pereira MJ Soares Vde M Martins MR Teixeira MT Souza EP Moura AS 《The Journal of nutritional biochemistry》2009,20(6):435-442
Overnutrition during critical developmental periods is believed to be a risk factor for the emergence of metabolic disorders in adulthood. The present study investigated the effects of pups overfeeding during lactation on offspring's insulin secretion. To study the consequences of overnutrition early in life in rats, litter size reduction has been shown to be an appropriate experimental model. To induce early postnatal overnutrition, litter size was reduced to three pups per litter at the third day following birth [overfed group (OG)]. In the control group (CG), the litter size was adjusted to 10 pups per litter. Metabolic parameters and glucose-stimulated insulin secretion were assessed. OG pups ingested more milk at 10 and 21 days and had an augmented food intake at 1 year compared to the CG. Consistently, body weight, body fat, and fasting plasma levels of insulin were higher in 1-year-old OG rats. In addition, OG rats exhibited enhanced insulin secretion, accompanied by elevated content of GLUT-2 in pancreatic islets compared to CG. These findings indicate that early postnatal overnutrition during a critical developmental period in life may program permanent alterations in glucose-stimulated insulin secretion. 相似文献
859.
The 2-methoxy derivative of estradiol is currently in Phase II clinical trial as an anticancer agent while the 4-methyl derivative has been shown to interact with cytoplasmic and nuclear estrogen receptors in rat pituitary gland and hypothalamus. We hypothesize that the 16alpha-(18)F-analogs of these estrogens could be suitable radiotracers to evaluate action mechanisms of the parent compounds. In this study we report the synthesis of the 16alpha-(18)F and 16alpha-(19)F-analogs of the A-ring substituted estradiols in high yield via stereoselective opening of the intermediate 16beta,17beta-O-cyclic sulfones with [(18)F]F(-) or F(-) followed by deprotection. 相似文献
860.
We examined the morphology of Skeletonema species occurring in coastal waters of southern Brazil, on the basis of LM, SEM, and TEM analyses of six isolated strains and of 13 field samples from the Patos Lagoon estuary and the adjacent Cassino Beach. We concluded that the genus Skeletonema is highly diverse in coastal waters of southern Brazil, with the occurrence of four confirmed species: S. costatum, S. pseudocostatum, S. potamos, and S. tropicum. In addition, EM details must still be provided for S. menzelii, and genetic studies should be conducted to confirm the identity of S. cf. grethae and S. subsalsum. The high diversity in this geographic area can be attributed to the proximity of the Subtropical Convergence and to the freshwater ecosystems of Patos Lagoon and La Plata River that favor the presence of warm‐, cold‐, and brackish‐water species. 相似文献