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Electrophoretic Studies (electrophoretic + studies)
Selected AbstractsPopulation structure in the Atlantic salmon: insights from 40 years of research into genetic protein variationJOURNAL OF FISH BIOLOGY, Issue 2005E. Verspoor Electrophoretic studies of proteins remain a primary source of insight into genetic diversity in many species including the Atlantic salmon Salmo salar, one of the most culturally and economically important fish species of the North Atlantic region. Since 1966, >350 scientific papers on protein variation have been published encompassing 25 000+ salmon from over 400 locations in >200 river systems across the species' distribution. Variation has been detected at 30% of the 110 protein loci screened, though most studies examine <40. The method has been applied largely to the investigation of population structure and differentiation, but work has also led to the systematic revision of the genus Salmo and remains the primary source of insight into hybridization in the wild with brown trout Salmo trutta. Spatial patterns of differentiation show temporal stability, both within and among river systems, and strongly support structuring of the species into river and tributary specific populations and the designation of European and North American populations as distinct sub-species. They also show widespread regional differentiation within both continents, beyond the marked subcontinental differences between Baltic Sea and Atlantic Ocean populations in Europe. Most of the differentiation probably reflects gene flow and founder events associated with colonization following the retreat of the glaciers from much of the species' modern range. However, variation at MEP-2* shows strong correlations with environmental temperature, both within and among rivers, and associations with phenotypic performance. This suggests selection is acting on the locus and provides compelling evidence for the local adaptation of populations. Protein studies have led to more population centred management of the species and have been exploited in the discrimination of regional stocks in mixed stock analysis in high seas fisheries, particularly in the Baltic Sea, and as markers for the assessment of stocking success. They have also advanced insight into how the genetic character of populations can be changed in cultivation and the potential impact of salmon aquaculture and stocking on wild populations. The method has been largely superseded by DNA based analyses, but the results remain highly relevant to Atlantic salmon management and conservation and are an irreplaceable data set for studying genetic stability of populations over time. [source] Cryoprotective additives and cryostabilisation effects on muscle fillets of the freshwater teleost fish Rohu carp (Labeo rohita) during prolonged frozen storageJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2006Shashi Kiran Jasra Abstract The effects of various cryoprotective additives separately and in combination were studied on the myofibrillar protein integrity, biochemical enzyme activity levels and muscle ultrastructure in the freshwater teleost fish Rohu carp (Labeo rohita). Fish muscle samples were divided into eight groups and immersed in different mixtures of cryoprotective additives (S1,S8), then frozen at , 20 or , 30 °C for 24 months. Electrophoretic studies revealed early (within 6 months) alteration of the myofibrillar proteins myosin light chain, ,-actinin and tropomyosin. Reduction of the storage temperature from , 20 to , 30 °C slowed down the degradative processes. Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated that fish muscle treated with cryoprotective mixture S8 (40 g L,1 sorbitol/3 g L,1 sodium tripolyphosphate/4 g L,1 sodium alginate) showed minimal post mortem changes in myofibrillar proteins. Ultrastructural results also revealed post mortem damage to the muscle, seen earliest (within 6 months) in the sample frozen-stored without additives (S2), as compared with the normal, unfrozen muscle (S1). The influence of cryoprotectants alone and in combination on fish muscle structural proteins, myosin and actin filaments (A and I bands), during prolonged frozen storage was investigated. After 12 months, samples frozen-stored with various cryoprotective additives (S2-S7), except S8, showed signs of myofibrillar disintegration. Beyond that time the degradative processes started showing up in all samples, with minimal muscle ultrastructural damage in sample S8. Again, reducing the storage temperature from , 20 to , 30 °C slowed down the degradative processes. Ultrastructural results correlated well with levels of biochemical enzymes (Ca2+ myofibrillar ATPase and succinic dehydrogenase) during frozen storage. This is the first report of the cryoprotective effects of these additives on this popular edible fish species. Of the various combinations of additives tested, cryoprotective mixture S8 was found to preserve the muscle structure longest under frozen storage conditions. However, even this mixture was only effective for 18 months at , 30 °C. Beyond that time the myofibrillar degradative processes were apparent with correlative electrophoretic, biochemical and ultrastructural studies. Copyright © 2006 Society of Chemical Industry [source] Copper(II),Girard's T complex as a promising anti-tumor agentAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2010A. M. A. El-Sokkary Abstract A copper(II) complex was evaluated for its anti-tumor activity. Firstly, electrophoretic studies were applied on the complex. These studies revealed the binding of the complex to calf thymus DNA, leading to a delay in electrophoretic mobility of the DNA molecule. Secondly, spectroscopic data pointed out that the ,max of DNA was shifted to a longer wavelength, which was accompanid by a hyperchromic shift. Moreover, the ,max of copper(II) complex was shifted to a shorter wavelength. The favorable reaction conditions between the DNA molecule and the copper(II) complex were studied. Thirdly, The effects of the ligand and the Cu(II) ion were tested separately on the DNA molecule by electrophoresis technique. Furthermore, the fluorescence quenching of DNA bound ethidium ion by Cu(II)-Girard's T complex was noticed. The IR spectral data of DNA before and after the reaction with the copper(II) complex indicated that the interaction takes place through the carbonyl group of DNA nucleobases. Finally, a significant increase in the mean survival of EAC (Ehrlich ascites carcinoma) tumor-bearing mice was observed when treated with the copper(II) complex. The tumor volume was also significantly reduced (p < 0.0001). Electrophoretic studies showed that the DNA pattern extracted from EAC cells of tumor-bearing mice was affected after treatment with the copper(II) complex. Flow cytometric studies showed that this complex may be taken into consideration in seeking novel anti-tumor agents. Copyright © 2010 John Wiley & Sons, Ltd. [source] Reversed-phase high-performance liquid chromatographic, size exclusion chromatographic and polyacrylamide gel electrophoretic studies of glycinin: evidence for molecular species and their association,dissociationBIOMEDICAL CHROMATOGRAPHY, Issue 12 2007Ravi Bhushan Abstract Isolation and purification of glycinin and its molecular species from an Indian soybean variety (JS-335) was achieved using polyacrylamide gel electrophoresis (PAGE), size exclusion chromatography (SEC) and reversed-phase high-performance liquid chromatography (RP-HPLC). Glycinin was found to have two molecular species (glycinin I and II), and only glycinin I underwent reversible dissociation,association system into , and , species. Glycinin I and II were not found to constitute a dissociation,association system. Glycinin II also did not dissociate under varying conditions of time, pH and ionic strength of buffer. Various species so dissociated were isolated, purified and characterized. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||