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Marine Origin (marine + origin)
Selected AbstractsAntifungal Cyclopeptides from Halobacillus litoralis YS3106 of Marine Origin.CHEMINFORM, Issue 51 2002Ling Yang No abstract is available for this article. [source] Ribosomal RNA gene fragments from fossilized cyanobacteria identified in primary gypsum from the late Miocene, ItalyGEOBIOLOGY, Issue 2 2010G. PANIERI Earth scientists have searched for signs of microscopic life in ancient samples of permafrost, ice, deep-sea sediments, amber, salt and chert. Until now, evidence of cyanobacteria has not been reported in any studies of ancient DNA older than a few thousand years. Here, we investigate morphologically, biochemically and genetically primary evaporites deposited in situ during the late Miocene (Messinian) Salinity Crisis from the north-eastern Apennines of Italy. The evaporites contain fossilized bacterial structures having identical morphological forms as modern microbes. We successfully extracted and amplified genetic material belonging to ancient cyanobacteria from gypsum crystals dating back to 5.910,5.816 Ma, when the Mediterranean became a giant hypersaline brine pool. This finding represents the oldest ancient cyanobacterial DNA to date. Our clone library and its phylogenetic comparison with present cyanobacterial populations point to a marine origin for the depositional basin. This investigation opens the possibility of including fossil cyanobacterial DNA into the palaeo-reconstruction of various environments and could also be used to quantify the ecological importance of cyanobacteria through geological time. These genetic markers serve as biosignatures providing important clues about ancient life and begin a new discussion concerning the debate on the origin of late Miocene evaporites in the Mediterranean. [source] Origin of deep saline groundwaters in the Vienne granitic rocks (France): constraints inferred from boron and strontium isotopesGEOFLUIDS (ELECTRONIC), Issue 2 2001J. Casanova Abstract As part of a preliminary geological characterization programme to assess the feasibility of an underground laboratory in granitic rock, a series of 17 deep boreholes (maximum depth, 900 m) was drilled by ANDRA in the Vienne district, France. A salinity gradient was demonstrated in the granitic waters with concentrations varying from approximately 1 g L,1 at 150 m depth at the top of the basement (beneath the sedimentary cover) to 10 g L,1 in the deeper part (from 400 to 600 m depth). Sr and B isotope ratios were measured in order to better understand the origin of the salinity and to evaluate the degree of water,rock interaction in the system. The results obtained were compared to those of mineral spring waters emerging from the granitic basement in the Massif Central. Evidence in support of a significant marine contribution include: (i) the Cl,Br investigations agree with a marine origin for the saline groundwaters without evolution from seawater; (ii) the 87Sr/86Sr ratio of the Vienne deep groundwaters (0.7078,0.7084) is in agreement with a palaeo-seawater isotopic signature; (iii) measured ,11B values for the deepest brine samples are enriched in 11B (up to 36.1,) relative to the granitic springs. The combined use of ,11B, Cl, B, Br, Sr contents and 87Sr/86Sr ratios makes it possible to define and quantify a mixing model between marine and crustal end-members in order to explain the origin of the deep saline groundwaters in the Vienne granitic rocks. [source] Investigation of wild caught whitefish, Coregonus lavaretus (L.), for infection with viral haemorrhagic septicaemia virus (VHSV) and experimental challenge of whitefish with VHSVJOURNAL OF FISH DISEASES, Issue 7 2004H F Skall Abstract One hundred and forty-eight wild whitefish, Coregonus lavaretus (L.), were caught by electrofishing and sampled for virological examination in December 1999 and 2000, during migration from the brackish water feeding grounds to the freshwater spawning grounds, where the whitefish may come into contact with farmed rainbow trout. All samples were examined on cell cultures. No viruses were isolated. Three viral haemorrhagic septicaemia virus (VHSV) isolates of different origin were tested in infection trials by immersion and intraperitoneal (IP) injection, using 1.5 g farmed whitefish: an isolate from wild caught marine fish, a farmed rainbow trout isolate with a suspected marine origin and a classical freshwater isolate. The isolates were highly pathogenic by IP injection where 99,100% of the whitefish died. Using an immersion challenge the rainbow trout isolates were moderately pathogenic with approximately 20% mortality, whereas the marine isolate was virtually non-pathogenic. At the end of the experiment it was possible to isolate VHSV from survivors infected with the marine and suspected marine isolates. Because of the low infection rate in wild whitefish in Denmark, the role of whitefish in the spread of VHSV in Denmark is probably not significant. The experimental studies, however, showed that whitefish are potential carriers of VHSV as they suffer only low mortality after infection but continue to carry virus. [source] CHARACTERIZATION AND COMPARISON OF COLLAGENS EXTRACTED FROM THE DIGESTIVE TRACT AND SKIN OF A JAPANESE AMBERJACK SERIOLA QUINQUERADIATAJOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2009MAKI NISHIMOTO ABSTRACT Collagen was extracted from the digestive tract and skin of a Japanese amberjack (Seriola quinqueradiata) by acid extraction and limited pepsin digestion. The amounts of collagen solubilized from the digestive tract were smaller than those from the skin. Based on the solubility in NaCl solution, electrophoretic and peptide map patterns, and amino acid composition, the main digestive tract collagen was identified as type I, having characteristics different from those of the body wall collagen in cyclostome intestine. Further, the degree of hydroxylation of prolyl and lysyl residues in the type I collagen of the digestive tract is significantly higher than that of the skin. Collagen preparations from the digestive tract have a higher ratio of type V collagen than those from the skin. Hence, the digestive tract collagen differs from that in the skin in the degree or property of intermolecular crosslinking, posttranslational modification, and molecular species composition. PRACTICAL APPLICATIONS Partial hydrolyzate of gelatin, in other word collagen peptide, has gained popularity as a food ingredient, as it has been suggested to have health benefits, such as improvement of skin and joint conditions. Recently, attention toward collagen derived from marine origin such as fish skin increased because of the outbreak of bovine spongiform encephalopathy. Large amounts of the digestive tract, stomach, intestine and adhesion tissues are generated by fishery industries and most of them are by-products of low value. Although these organs are also rich in collagen, the collagen in fish digestive tract has not been characterized. The present study demonstrates that the collagen in digestive tract differs from the skin collagen in the solubility, posttranslational modification and molecular species composition. These facts suggest that modified collagen peptides might be obtained from the digestive tract. [source] Structure elucidation of aplidine metabolites formed in vitro by human liver microsomes using triple quadrupole mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 6 2005Esther F. A. Brandon Abstract The cyclic depsipeptide aplidine is a new anti-cancer drug of marine origin. Four metabolites of this compound were found after incubation with pooled human microsomes using gradient high-performance liquid chromatography with ultraviolet detection. After chromatographic isolation, the metabolites have been identified using nano-electrospray triple quadrupole mass spectrometry. A highly specific sodium-ion interaction with the cyclic structure opens the depsipeptide ring, and cleavage of the amino acid residues gives sequence information when activated by collision-induced dissociation in the second quadrupole. The aplidine molecule could undergo the following metabolic reactions: hydroxylation at the isopropyl group (metabolites apli-h 1 and apli-h 2); C-dealkylation at the N(Me)-leucine group (metabolite apli-da); hydroxylation at the isopropyl group and C-dealkylation at the N(Me)-leucine group (metabolite apli-da/h), and C-demethylation at the threonine group (metabolite apli-dm). The identification of these metabolites formed in vitro may greatly aid the elucidation of the metabolic pathways of aplidine in humans. Copyright © 2005 John Wiley & Sons, Ltd. [source] POST-DRILLING ANALYSIS OF THE NORTH FALKLAND BASIN, PART 1: TECTONO-STRATIGRAPHIC FRAMEWORKJOURNAL OF PETROLEUM GEOLOGY, Issue 3 2000P. C. Richards Six wells were drilled in the extensional North Falkland Basin in 1998. The wells encountered a Devonian to Cenozoic stratigraphy dominated by thick Mesozoic syn- and post-rift successions. Although most previously published models predicted that the succession would most likely be of marine origin, it is in fact predominantly terrestrial; marine conditions did not become established in the basin until the Late Cretaceous. The oldest rocks recorded are Devonian and these were penetrated in only one well. The overlying succession comprises: a fluvio-lacustrine, early syn-rft interval of ?mid-Jurassic to Tithonian age; a late syn-rift fluvio-lacustrine interval of Tithonian to Berriasian age; a rift-sag transitional unit of Berriasian to Valanginian age; an early post-rift lacustrine unit of Valanginian to early Aptian age; a middle post-rift, transgressive unit of Aptian to Albian age; a late post-rift, terrestrial to marine unit of Albian to early Palaeocene age; and a post-up lift thermal subsidence unit of Palaeocene to Recent age. Much of the sediment appears to have been derived from volcanic and/or metamorphic terranes, probably located to the north or NW of the basin. As well as the volcanic material which occurs in the ground mass and as lithoclasts in many of the units, some volcaniclastic rocks and minor amounts of ashfall tufls are observed, particularly within the late syn-rift succession. [source] Aragonite crystalline matrix as an instructive microenvironment for neural developmentJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 8 2008H. Peretz Abstract The ability to mimic cell,matrix interactions in a way that closely resembles the natural environment is of a great importance for both basic neuroscience and for fabrication of potent scaffolding materials for nervous tissue engineering. Such scaffolding materials should not only facilitate cell attachment but also create a microenvironment that provides essential developmental and survival cues. We previously found that porous aragonite crystalline matrices of marine origin are an adequate and active biomaterial that promotes neural cell growth and tissue development. Here we studied the mechanism underlying these neural cell,material interactions, focusing on the three-dimensional (3D) surface architecture and matrix activity of these scaffolds. We introduced a new cloning technique of the hydrozoan Millepora dichotoma, through which calcein or 45Ca2+ were incorporated into the organism's growing skeleton and neuronal cells could then be cultured on the labelled matrices. Herein, we describe the role of matrix 3D architecture on neural cell type composition and survival in culture, and report for the first time on the capacity of neurons and astrocytes to exploit calcium ions from the supporting biomatrix. We found that hippocampal cells growing on the prelabelled aragonite lattice took up aragonite-derived Ca2+, and even enhanced this uptake when extracellular calcium ions were chelated by EGTA. When the aragonite-derived Ca2+ uptake was omitted by culturing the cells on coral skeletons coated with gold, cell survival was reduced but not arrested, suggesting a role for matrix architecture in neural survival. In addition, we found that the effects of scaffold architecture and chemistry on cell survival were more profound for neurons than for astrocytes. We submit that translocation of calcium from the biomaterial to the cells activates a variety of membrane-bound signalling molecules and leads to the subsequent cell behaviour. This kind of cell,material interaction possesses great potential for fabricating advanced biomaterials for neural tissue-engineering applications. Copyright © 2008 John Wiley & Sons, Ltd. [source] A study of candidate marine target impact craters in Arabia Terra, MarsMETEORITICS & PLANETARY SCIENCE, Issue 6 2010Germari de VILLIERS Arabia Terra is a region on Mars that straddles the crustal dichotomy, and several proposed shorelines are located in the area. Shallow marine impact craters on Mars likely would exhibit features like those on Earth, including characteristic morphological features that are distinctly different from that of craters formed on land. Common attributes of terrestrial marine impact craters include features of wet mass movement such as gravity slumps and debris flows; radial gullies leading into the crater depression; resurge deposits and blocks of dislocated materials; crater rim collapse or breaching of the crater wall; a central peak terrace or peak ring terrace; and subdued topography (an indicator of both age and possible flood inundation immediately following impact). In this article, these features have been used to evaluate craters on Mars as to a possible marine origin. This study used a simple quantification system to approximately judge and rank shallow marine impact crater candidates based on features observed in terrestrial analogs. Based on the quantification system, 77 potential shallow marine impact craters were found within an area bounded by 20°N and 40°N as well as 20°W and 20°E. Nine exemplary candidates were ranked with total scores of 70% or more. In a second, smaller study area, impact craters of approximately similar size and age were evaluated as a comparison and average total scores are 35%, indicating that there is some morphological difference between craters inside and outside the proposed shorelines. Results of this type of study are useful in helping to develop a general means of classification and characterization of potential marine craters. [source] Evaluation of fisheries by-catch and by-product meals in diets for red drum Sciaenops ocellatus L.AQUACULTURE RESEARCH, Issue 16 2005Kasey W Whiteman Abstract This study evaluated various by-catch and by-product meals of marine origin with red drum (Sciaenops ocellatus L.). Four different kinds of by-catch or by-product meals [shrimp by-catch meal from shrimp trawling, Pacific white shrimp (Litopenaeus vannamei (Boone)) processing waste meal, red salmon (Oncorhynchus nerka (Walbaum)) head meal, and Pacific whiting (Merluccius productus (Ayres)) meal] were substituted for Special SelectÔ menhaden fish meal at 33% or 67% of crude protein in diets formulated to contain 40% crude protein, 12% lipid, and 14.6 kJ digestible energy g,1. Each of these diets and three additional diets consisting of shrimp processing waste meal formulated on a digestible-protein basis and two Pacific whiting diets containing reduced levels of ash were also evaluated in two 6-week feeding trials with juvenile red drum (initial weight of 4,5 and 1,2 g fish,1 in trials 1 and 2). Red drum fed by-catch meal at either level of substitution performed as well as fish fed the control diet; whereas, fish fed shrimp processing waste meal diets had significantly (P,0.05) reduced weight gain and feed efficiency ratio values compared with the controls, even when fed on a digestible-protein basis. The diets containing Pacific whiting at either levels of substitution and regardless of ash level supported similar performance of red drum as those fed the control diet. Fish fed the red salmon head meal diet fared poorly, probably owing to an excessive amount of lipid in the diet that became rancid. Overall, by-catch meal associated with shrimp trawling and Pacific whiting appear to be suitable protein feedstuffs for red drum. [source] Phylogenetic relationships of Atherina hepsetus and Atherina boyeri (Pisces: Atherinidae) populations from Greece, based on mtDNA sequencesBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2007ELENI KLOSSA-KILIA The genetic divergence and the phylogenetic relationships of six Atherina boyeri (freshwater and marine origin) and five Atherina hepsetus populations from Greece were investigated using partial sequence analysis of 12s rRNA, 16s rRNA and control region mtDNA segments. Three different well divergent groups were revealed; the first one includes A. boyeri populations living in the sea, the second includes A. boyeri populations living in the lakes and lagoons whereas the third one includes all A. hepsetus populations. Fifty-seven different haplotypes were detected among the populations studied. In all three mtDNA segments examined, sequence analysis revealed the existence of fixed haplotypic differences discriminating A. boyeri populations inhabiting the lagoon and the lakes from both the coastal A. boyeri and the A. hepsetus populations. The genetic divergence values estimated between coastal (marine) A. boyeri populations and those living in the lagoon and the lakes are of the same order of magnitude as those observed among coastal A. boyeri and A. hepsetus populations. The results obtained by different phylogenetic methods were identical. The deep sequence divergence with the fixed different haplotypes observed suggests the occurrence of a cryptic or sibling species within A. boyeri complex. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 92, 151,161. [source] Historical biogeography of Hexabathynella , a cosmopolitan genus of groundwater Syncarida (Crustacea, Bathynellacea, Parabathynellidae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2003ANA I. CAMACHO Hexabathynella is the only cosmopolitan genus of the order Bathynellacea (Crustacea). The known species number 18, found in Europe (9), Africa (1), South America (2), North America (3) and Australia and New Zealand (3). Phylogenetic analysis suggests that the least derived species are those from South America and the most derived those from the Iberian Peninsula, North America and Australia. The five species with the most plesiomorphic characters occur in salt or brackish water, which supports a marine origin for the genus. Phylogenetic and biogeographical analyses suggest that the distribution of the genus can be explained by dispersion and a double vicariant biogeographical model based on plate tectonics and the evolution of the Tethys during the Mesozoic and Cenozoic. © 2003 The Linnean Society of London . Biological Journal of the Linnean Society , 2003, 78 , 457,466. [source] Dietary intervention increases n-3 long-chain polyunsaturated fatty acids in skeletal muscle membrane phospholipids of obese subjects.CLINICAL ENDOCRINOLOGY, Issue 2 2006Implications for insulin sensitivity Summary Objective, Cross-sectional studies suggest that the fatty acid (FA) composition of phospholipids in skeletal muscle cell membrane may modulate insulin sensitivity in humans. We examined the impact of a hypocaloric low-fat dietary intervention on membrane FA composition and insulin sensitivity. Design, Muscle membrane FA profiles were determined in muscle (vastus lateralis) biopsies from 21 obese subjects before and after 6 months of dietary restriction. Diet instructions emphasized low intake of FA of marine origin by recommending lean fish and prohibiting fatty fish and fish oil supplements. Insulin resistance was estimated by the homeostasis model assessment (HOMA-IR). Results, The mean weight loss was 5·1 kg (range ,15·3 to +1·3 kg). BMI decreased from 36·5 to 34·9 kg/m2 (P = 0·003). Saturated FA (SFA) decreased 11% (P = 0·0001). Polyunsaturated FA (PUFA)n-6 increased 4% (P = 0·003). Long-chain PUFAn-3 increased 51% (P = 0·0001), mainly due to a 75% increase (P < 0·0001) in docosahexaenoic acid. Changes in HOMA-IR correlated significantly with changes in long-chain PUFAn-3 (R = ,0·57, P < 0·01), SFA (R = 0·58, P < 0·01) and waist circumference (R = 0·46, P < 0·05). A multivariate linear regression analysis that included changes in weight, fat mass, waist circumference, plasma lipids, PUFA, SFA and long-chain PUFAn-3 indicated that SFA and long-chain PUFAn-3 were independent predictors of HOMA-IR (R2 = 0·33, P < 0·01). Conclusions, A hypocaloric low-fat dietary intervention programme increased incorporation of long-chain PUFAn-3 and reduced SFA in skeletal muscle membrane phospholipids of obese subjects, a setting that may impact on insulin action. [source] | ||||||||||||||||