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Minor Components (minor + component)
Selected AbstractsPHENOLIC COMPOUNDS, TOCOPHEROLS AND OTHER MINOR COMPONENTS IN VIRGIN OLIVE OILS OF SOME TUNISIAN VARIETIESJOURNAL OF FOOD BIOCHEMISTRY, Issue 2 2007D. KRICHENE ABSTRACT The phenols, ,-tocopherols, fatty acids and oxidative stability of six monovarietal virgin olive oils (VOOs) were determined. Fourteen phenolic compounds were detected and quantified by solid phase extraction and reversed phase-high performance liquid chromatography. Dialdehydic form of elenolic acid linked to tyrosol and hydroxytyrosol, oleuropein and ligstroside aglycones were the main components in all samples. Pinoresinol was the most abundant component in lignan fraction. The total phenol content of these monovarietal oils varied from 66.82 mg/kg in "Neb Jmel" oil to 662.74 mg/kg in "El Hor" oil. A wide range of ,-tocopherol contents was also noticed; it varied from 141.94 mg/kg in "Semni" variety to 364.23 mg/kg in "Jdallou" variety. With regard to pigments, chlorophylls and carotenoids were found at variable concentrations: with median values of 11.33 and 3.10 mg/kg, respectively. Among the studied varieties, "Oueslati" and El Hor were characterized by the lowest levels of palmitic and linoleic acids and the highest values of oleic acid. [source] Walnut (Juglans regia L.): genetic resources, chemistry, by-productsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2010Marcela L Martínez Abstract Walnut (Juglans regia L.) is the most widespread tree nut in the world. There is a great diversity of genotypes differing in forestry, productivity, physical and chemical nut traits. Some of them have been evaluated as promising and may serve as germplasm sources for breeding. The nutritional importance of the nut is related to the seed (kernel). It is a nutrient-dense food mainly owing to its oil content (up to 740 g kg,1 in some commercial varieties), which can be extracted easily by screw pressing and consumed without refining. Walnut oil composition is dominated largely by unsaturated fatty acids (mainly linoleic together with lesser amounts of oleic and linolenic acids). Minor components of walnut oil include tocopherols, phospholipids, sphingolipids, sterols, hydrocarbons and volatile compounds. Phenolic compounds, present at high levels in the seed coat but poorly extracted with the oil, have been extensively characterised and found to possess strong antioxidant properties. The oil extraction residue is rich in proteins (unusually high in arginine, glutamic and aspartic acids) and has been employed in the formulation of various functional food products. This review describes current scientific knowledge concerning walnut genetic resources and composition as well as by-product obtainment and characteristics. Copyright © 2010 Society of Chemical Industry [source] Mixed metaplastic carcinoma of the breast associated with pregnancy: Diagnostic dilemmas in fine-needle aspiration cytologyDIAGNOSTIC CYTOPATHOLOGY, Issue 10 2009Lazaros Skagias M.D. Abstract Metaplastic carcinoma of the breast represents a rare entity characterized by the simultaneous presence of ductal, squamous, and/or mesenchymal components in several proportions. There are limitations in fine-needle aspiration diagnosis due to its pathological heterogeneity. When it develops under pregnancy and lactation influence, the cytologic evaluation appears to be more difficult and accurate diagnosis often proves challenging. We describe a case of mixed metaplastic carcinoma with dominant areas of squamous metaplasia, sarcomatoid stroma with spindle cells, and a minor component of cartilaginous metaplasia. We notify our experience in diagnostic approach of this entity focusing on differential diagnosis. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] Cytology of the central zone of the prostateDIAGNOSTIC CYTOPATHOLOGY, Issue 5 2003Lars Egevad M.D., Ph.D. Abstract The prostate has three anatomical regions: the peripheral, transition, and central zones (CZ). The CZ has distinct histological features, but its cytological morphology has not been described. This study was done on surgical specimens to ensure that samples were representative of the CZ, and that no prostatic intraepithelial neoplasia (PIN) or cancer contaminated the smears. An incision was made in the CZ of 51 prostatectomy specimens, and cells were scraped from cut surfaces. After exclusion of samples contaminated by PIN or cancer or with poor cell yield, 39 Giemsa-stained smears remained for analysis. Large branching epithelial sheets with geographic architecture and crowded nuclei were seen in 97% of smears. Epithelial clusters with elongated palisaded nuclei were identified in 80% of cases, but were always a minor component. Visible nucleoli (97%), cytoplasmic vacuoles (97%), and smooth muscle cells in the background (95%) were common. Blue-green cytoplasmic granules resembling seminal vesicle pigment were seen in 97%. Magenta-colored cytoplasmic pigment, similar to granules seen in other regions of the prostate, was found in 74%. Recognition of CZ epithelium as a benign constituent of prostate cytology is important because elongated cells, crowded nuclei, and visible nucleoli may otherwise be misinterpreted as PIN or cancer. Diagn. Cytopathol. 2003;28:239,244. © 2003 Wiley-Liss, Inc. [source] The role of environmental gradients in non-native plant invasion into burnt areas of Yosemite National Park, CaliforniaDIVERSITY AND DISTRIBUTIONS, Issue 2 2006Rob Klinger ABSTRACT Fire is known to facilitate the invasion of many non-native plant species, but how invasion into burnt areas varies along environmental gradients is not well-understood. We used two pre-existing data sets to analyse patterns of invasion by non-native plant species into burnt areas along gradients of topography, soil and vegetation structure in Yosemite National Park, California, USA. A total of 46 non-native species (all herbaceous) were recorded in the two data sets. They occurred in all seven of the major plant formations in the park, but were least common in subalpine and upper montane conifer forests. There was no significant difference in species richness or cover of non-natives between burnt and unburnt areas for either data set, and environmental gradients had a stronger effect on patterns of non-native species distribution, abundance and species composition than burning. Cover and species richness of non-natives had significant positive correlations with slope (steepness) and herbaceous cover, while species richness had significant negative correlations with elevation, the number of years post-burn, and cover of woody vegetation. Non-native species comprised a relatively minor component of the vegetation in both burnt and unburnt areas in Yosemite (percentage species = 4%, mean cover < 6.0%), and those species that did occur in burnt areas tended not to persist over time. The results indicate that in many western montane ecosystems, fire alone will not necessarily result in increased rates of invasion into burnt areas. However, it would be premature to conclude that non-native species could not affect post-fire succession patterns in these systems. Short fire-return intervals and high fire severity coupled with increased propagule pressure from areas used heavily by humans could still lead to high rates of invasion, establishment and spread even in highly protected areas such as Yosemite. [source] Synergistic sex pheromone components of the grey-spotted tussock moth, Orgyia ericaeENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2010Guo-Fa Chen Abstract The grey-spotted tussock moth, Orgyia ericae Germar (Lepidoptera: Lymantriidae), is an important pest of deciduous trees and woody scrublands in northern China. In a field trapping experiment conducted during the flight of the first generation of 2009, synthetic (Z)-6-heneicosen-11-one, a common Orgyia spp. sex pheromone component, attracted O. ericae males. Gas chromatography-mass spectrometry analyses (full scan or selected ion-monitoring mode) of pheromone gland extracts from females revealed the presence of a major, a minor, and a trace component, i.e., (6Z,9Z)-heneicosa-6,9-diene, (6Z,9Z)-tricosa-6,9-diene, and (Z)-6-heneicosen-11-one, respectively. Field experiments during the flight of the second generation showed that (6Z,9Z)-tricosa-6,9-diene, the minor component, was inactive alone or in any combination with the other two components, whereas (6Z,9Z)-heneicosa-6,9-diene and (Z)-6-heneicosen-11-one were weakly attractive when tested individually. However, traps baited with a binary blend of (6Z,9Z)-heneicosa-6,9-diene and (Z)-6-heneicosen-11-one caught seven-fold more moths than any other treatment (except the ternary blend), indicating a strong synergistic interaction between the two components. The analytical and field trapping data suggested that (6Z,9Z)-heneicosa-6,9-diene and (Z)-6-heneicosen-11-one are likely the key sex pheromone components of female O. ericae. This synergistic blend will be useful as an efficient monitoring tool, and possible control tool, to combat this economically and ecologically important forest defoliator. [source] Single olfactory sensory neurons simultaneously integrate the components of an odour mixtureEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2003Patricia Duchamp-Viret Abstract Most odours are complex mixtures. However, the capacities of olfactory sensory neurons (OSNs) to process complex odour stimuli have never been explored in air-breathing vertebrates. To face this issue, the present study compares the electrical responses of single OSNs to two odour molecules, delivered singly and mixed together, in rats in vivo. This work is the first aimed at demonstrating that single OSNs simultaneously integrate several chemical signals and which, furthermore, attempts to describe such processes for the whole concentration range over which single OSNs can work. The results stress that complex interactions occur between components in odour mixtures and that OSN responses to such mixtures are not simply predictable from the responses to their components. Three types of interactions are described. They are termed suppression, hypoadditivity and synergy, in accord with psychophysical terminology. This allows us to draw links between peripheral odour reception and central odour coding. Indeed, events occurring in single OSNs may account for the dominating or even the masking effects of odour molecules in complex mixtures, i.e. for the prevailing action of a minor component in the final qualitative perception of a mixture. We conclude that our observations with binary mixtures anticipate the complexity of processes which may rise at the level of a single OSN in physiological conditions. Following this hypothesis, a natural odour would induce a multi-chemical integration at the level of single OSNs which may result in refining their individual odour-coding properties, leading them to play a crucial role in the final performance of the olfactory system. [source] The N-glycans of yellow jacket venom hyaluronidases and the protein sequence of its major isoform in Vespula vulgarisFEBS JOURNAL, Issue 20 2005Daniel Kolarich Hyaluronidase (E.C. 3.2.1.35), one of the three major allergens of yellow jacket venom, is a glycoprotein of 45 kDa that is largely responsible for the cross-reactivity of wasp and bee venoms with sera of allergic patients. The asparagine-linked carbohydrate often appears to constitute the common IgE-binding determinant. Using a combination of MALDI MS and HPLC of 2-aminopyridine-labelled glycans, we found core-difucosylated paucimannosidic glycans to be the major species in the 43,45 kDa band of Vespula vulgaris and also in the corresponding bands of venoms from five other wasp species (V. germanica, V. maculifrons, V. pensylvanica, V. flavopilosa and V. squamosa). Concomitant peptide mapping of the V. vulgaris 43 kDa band identified the known hyaluronidase, Ves v 2 (SwissProt P49370), but only as a minor component. De novo sequencing by tandem MS revealed the predominating peptides to resemble a different, yet homologous, sequence. cDNA cloning retrieved a sequence with 58 and 59% homology to the previously known isoform and to the Dolichovespula maculata and Polistes annularis hyaluronidases. Close homologues of this new, putative hyaluronidase b (Ves v 2b) were also the major isoform in the other wasp venoms. [source] Lability of organic carbon in lakes of different trophic statusFRESHWATER BIOLOGY, Issue 6 2009A. P. OSTAPENIA Summary 1. We used first-order kinetic parameters of biological oxygen demand (BOD), the constant of aerobic decomposition (k) and the asymptotic value of BOD (BODult), to characterise the lability of organic carbon pools in six lakes of different trophic state: L. Naroch, L. Miastro and L. Batorino (Belarus), L. Kinneret (Israel), L. Ladoga (Russia) and L. Mendota (U.S.A.). The relative contributions of labile and refractory organic carbon fractions to the pool of total organic carbon (TOC) in these lakes were quantified. We also determined the amounts of labile organic carbon within the dissolved and particulate TOC pools in the three Belarus lakes. 2. Mean annual chlorophyll concentrations (used as a proxy for lake trophic state) ranged from 2.3 to 50.6 ,g L,1, labile organic carbon (OCL = 0.3BODult) from 0.75 to 2.95 mg C L,1 and k from 0.044 to 0.14 day,1. 3. Our data showed that there were greater concentrations of OCL but lower k values in more productive lakes. 4. In all cases, the DOC fraction dominated the TOC pool. OCL was a minor component of the TOC pool averaging about 20%, irrespective of lake trophic state. 5. In all the lakes, most (c. 85%) of the DOC pool was refractory, corresponding with published data based on measurements of bacterial production and DOC depletion. In contrast, a larger fraction (27,55%) of the particulate organic carbon (POC) pool was labile. The relative amount of POC in the TOC pool tended to increase with increasing lake productivity. 6. Long-term BOD incubations can be valuable in quantifying the rates of breakdown of the combined particulate and dissolved organic carbon pools and in characterising the relative proportions of the labile and recalcitrant fractions of these pools. If verified from a larger number of lakes our results could have important general implications. [source] Low algal carbon content and its effect on the C : P stoichiometry of periphytonFRESHWATER BIOLOGY, Issue 11 2005PAUL C. FROST Summary 1. We examined the contribution of algal cells to periphytic organic carbon and assessed the effects of variable biomass composition on the carbon : phosphorus (C : P) ratio of periphyton. We compiled more than 5000 published and unpublished observations of periphytic carbon : chlorophyll a (C : Chl) ratios, an index of algal prevalence, from a variety of substrata collected from lake and low-salinity coastal habitats. In addition, we converted estimates of algal biovolume into algal C to obtain an independent measure of cellular algal carbon in periphyton. This information was used in a model relating periphyton C : P ratio to algal cellular carbon, the algal C : P ratio, and the C : P ratio of non-algal organic matter in periphyton. 2. The mean C : Chl ratio of periphyton (405) was relatively high with values in >25% of the samples exceeding 500. On average, 8.4% of total periphyton C was accounted for by C in algal cells. Only 15% of samples were found to have more than 15% periphyton C in cellular algal carbon. Our model showed a nonlinear relationship between periphytic C : P ratios and the C : P ratio of algal cells in the periphyton when non-algal organic matter was present. However, even at relatively low cellular algal C (<10% of total C), algal C : P ratios can strongly affect the C : P ratio of periphyton as a whole (i.e. algal cells plus other organic matter). 3. The high C : Chl ratios and the low biovolume-derived algal C of periphyton samples in our data set indicate that algal cells are typically a minor component of organic carbon in periphyton, However, this minor contribution would not preclude algal cellular stoichiometry from notably influencing periphyton C : P ratios. [source] Petrogenesis and tectonic setting of bimodal volcanism in the Sakoli Mobile Belt, Central Indian shieldISLAND ARC, Issue 1 2009Talat Ahmad Abstract The Sakoli Mobile Belt comprises bimodal volcanic rocks that include metabasalt, rhyolite, tuffs, and epiclastic rocks with metapelites, quartzite, arkose, conglomerate, and banded iron formation (BIF). Mafic volcanic rocks are tholeiitic to quartz-tholeiitic with normative quartz and hypersthene. SiO2 shows a large compositional gap between the basic and acidic volcanics, depicting their bimodal nature. Both the volcanics have distinct geochemical trends but display some similarity in terms of enriched light rare earth element,large ion lithophile element characteristics with positive anomalies for U, Pb, and Th and distinct negative anomalies for Nb, P, and Ti. These characteristics are typical of continental rift volcanism. Both the volcanic rocks show strong negative Sr and Eu anomalies indicating fractionation of plagioclases and K-feldspars, respectively. The high Fe/Mg ratios for the basic rocks indicate their evolved nature. Whole rock Sm,Nd isochrons for the acidic volcanic rocks indicate an age of crystallization for these volcanic rocks at about 1675 ± 180 Ma (initial 143Nd/144Nd = 0.51017 ± 0.00017, mean square weighted deviate [MSWD] = 1.6). The ,Ndt (t = 2000 Ma) varies between ,0.19 and +2.22 for the basic volcanic rock and between ,2.85 and ,4.29 for the acidic volcanic rocks. Depleted mantle model ages vary from 2000 to 2275 Ma for the basic and from 2426 to 2777 Ma for the acidic volcanic rocks, respectively. These model ages indicate that protoliths for the acidic volcanic rocks probably had a much longer crustal residence time. Predominantly basaltic magma erupted during the deposition of the Dhabetekri Formation and part of it pooled at crustal or shallower subcrustal levels that probably triggered partial melting to generate the acidic magma. The influence of basic magma on the genesis of acidic magma is indicated by the higher Ni and Cr abundance at the observed silica levels of the acidic magma. A subsequent pulse of basic magma, which became crustally contaminated, erupted as minor component along with the dominantly acidic volcanics during the deposition of the Bhiwapur Formation. [source] Using quantitative real-time PCR to detect salmonid prey in scats of grey Halichoerus grypus and harbour Phoca vitulina seals in Scotland , an experimental and field studyJOURNAL OF APPLIED ECOLOGY, Issue 2 2008I. Matejusová Summary 1There is considerable debate over the impact of seal predation on salmonid populations in both the Atlantic and Pacific oceans. Conventional hard-part analysis of scats has suggested that salmonids represent a minor component of the diet of grey seals (Halichoerus grypus) and harbour seals (Phoca vitulina) in the UK. However, it is unclear whether this is an accurate reflection of the diet or due to methodological problems. To investigate this issue, we applied quantitative PCR (qPCR) to examine the presence of salmonids in the diet of seals in the Moray Firth, UK, during the summers of 2003 and 2005. 2Two qPCR assays were designed to detect Atlantic salmon Salmo salar and sea trout Salmo trutta DNA in field samples and experimentally spiked scats. The proportion of scats sampled in the field that were positive for salmonid DNA was low (ª10%). However, the DNA technique consistently resulted in more positive scats than when hard-part analysis was used. 3An experimental study using spiked scat material revealed a highly significant negative relationship between Ct values obtained from the Atlantic salmon qPCR assay and the proportion of Atlantic salmon material added to scats. The Ct value denotes the cycle number at which the increasing fluorescence signal of target DNA crosses a threshold value. Ct values from field-collected seal scats suggested they contained a very low concentration of salmonid remains (1,5%) based on an approximate calibration curve constructed from the experimental data. 4Synthesis and applications. The qPCR assay approach was shown to be highly efficient and consistent in detection of salmonids from seal scats, and to be more sensitive than conventional hard-parts analysis. Nevertheless, our results confirm previous studies indicating that salmonids are not common prey for seals in these Scottish estuaries. These studies support current management practice, which focuses on control of the small number of seals that move into key salmonid rivers, rather than targeting the larger groups of animals that haul-out in nearby estuaries. [source] Organic mound-building ants: their impact on soil properties in temperate and boreal forestsJOURNAL OF APPLIED ENTOMOLOGY, Issue 4 2008M. F. Jurgensen Abstract Ants are important components of most soil invertebrate communities, and can affect the flow of energy, nutrients and water through many terrestrial ecosystems. The vast majority of ant species build nests in the mineral soil, but a small group of ants in temperate and boreal forests of Eurasia and North America build large parts of their nests above-ground using organic materials collected from the surrounding soil. Many studies have shown that ants nesting in mineral soil can affect water infiltration rates, soil organic matter (OM) content, and nutrient cycling, but much less is known on how mound-building ants influence soil physical and chemical properties. In this paper we summarize what is known on the soil impacts of organic mound-building ants in temperate and boreal forests, and how these ants could be affected by ecosystem disturbance and future climate change. Much of this information comes from studies on Formica rufa group ants in Europe, which showed that CO2 emissions and concentrations of C, N, and P are usually higher in ant mounds than in the surrounding forest soil. However, ant mounds are a minor component of total soil C and nutrient pools, but they do increase spatial heterogeneity of soil water and available nutrients. Mound-building ants can also impact tree growth, which could change the quantity and quality of OM added to soil. Forest management, fire, and projected climate change, especially in boreal forests, could affect mound-building ant population dynamics, and indirectly, soil properties. [source] Is the (E)- , -farnesene only volatile terpenoid in aphids?JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2005F. Francis Abstract:, Herbivore insects use a broad range of chemical cues to locate their host to feed or to oviposit. Whether several plant volatiles are effective allelochemicals for insects, the latter also emit molecules which have infochemical role. The (E)- , -farnesene (EBF) is a well-known aphid alarm pheromone commonly found in all previously tested species. Analysis of the released molecules from 23 aphid species, mainly collected on their natural host plant from May to July, was performed by gas chromatography,mass spectrometry. While EBF was identified as the main volatile substance in 16 species, alone or associated with other molecules, the alarm pheromone was only a minor component of the volatile molecule pattern of five other species. Moreover, two species, Euceraphis punctipennis and Drepanosiphum platanoides, did not release EBF at all but other terpenes were identified. This original observation raised the question on the utility and the source of the non-EBF volatiles. Are these potential infochemical substances produced by the aphid or only absorbed from the host plant? Here we determined that terpenes released by insects were not only provided by the host plants. Indeed, Megoura viciae emitted additional molecules than the ones from several aphid species reared on the same host plant. Moreover, no systematic relation between the feeding behaviour of the aphid species and the volatile releases was observed. Aphid terpene composition and proportion would provide reliable cues to identify the emitting organism, plant or insect. The next step of this work will be to determine the infochemical role of terpenes found in the range of tested aphid samples to better understand the relations between the different tritrophic levels. [source] Internal Validation of the AmpFlSTR YfilerÔ Amplification Kit for Use in Forensic CaseworkJOURNAL OF FORENSIC SCIENCES, Issue 1 2008Ann Marie Gross M.S. Abstract:, Y-chromosomal short-tandem repeat (Y-STR) amplification has been used in forensic casework at the Bureau of Criminal Apprehension (BCA) Forensic Science Laboratory since 2003. At that time, two separate amplifications were required to type the SWGDAM recommended loci (DYS19, DYS385a/b, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS438, and DYS439). The YfilerÔ kit coamplifies these loci as well as DYS437, DYS448, DYS456, DYS458, DYS635, and Y GATA H4. The YfilerÔ kit was validated following the internal validations outlined in the SWGDAM revised validation guidelines. Our studies show that 0.125 ng of male DNA will generate a complete 17 locus profile and that as little as 0.06 ng of male DNA yields an average of nine loci. In the male,male mixtures, a complete profile from the minor component was detected up to 1:5 ratio; most of the alleles of the minor component were detected at a 1:10 ratio and more than half the alleles of the minor component were detected at a 1:20 ratio. Complete YSTR profiles were obtained when 500 pg male DNA was mixed with female DNA at ratios up to 1:1000. At ratios of 1:5000 and 1:10,000 (male DNA to female DNA) inhibition of the YSTR amplification was evident. The YSTR results obtained for the adjudicated case samples gave significantly more probative information than the autosomal results. Our studies demonstrate that the YfilerÔ kit is extremely sensitive, does not exhibit cross-reactivity with female DNA, successfully types male DNA in the presence of overwhelming amounts of female DNA and is successful in typing actual forensic samples from adjudicated cases. [source] WINTER PHYTOPLANKTON BLOOMS UNDER ICE ASSOCIATED WITH ELEVATED OXYGEN LEVELS,JOURNAL OF PHYCOLOGY, Issue 6 2002Karen A. Phillips Many shallow lakes in north temperate zones experience reduced dissolved oxygen concentration under ice. However, some shallow lakes display supersaturated dissolved oxygen concentrations (>20 mg·L,1) in late winter under conditions of maximum ice thickness. During the winters of 1996, 1997, and 1999, we collected phytoplankton samples from Arrowwood Lake near Pingree, North Dakota to determine whether a specific alga was involved in dissolved oxygen supersaturation in this lake. Although dissolved oxygen supersaturation was not observed during this period, we did observe an increase in dissolved oxygen concentration that was associated with a phytoplankton bloom during late February and early March in both 1996 and 1997. In 1996, the bloom was composed of the dinoflagellate, Peridinium aciculiferum (Lemm.) Lemm. and several species of cryptomonads. A similar bloom of P. aciculiferum was followed by a bloom of several species of euglenoids in 1997. In contrast, P. aciculiferum was only a minor component of the winter phytoplankton, dissolved oxygen concentrations remained low, and no bloom event was observed in 1999. Statistical analyses indicated a significant relationship (rs = 0.57, P = 0.019) between dissolved oxygen levels and the density of the dinoflagellate, P. aciculiferum, but no significant relationship between dissolved oxygen levels and densities of other phytoplankton. These results suggest that the elevated levels of dissolved oxygen are associated with the dinoflagellate, P. aciculiferum. This bloom was most likely the result of an excystment event rather than a general growth response. [source] Lunar regolith breccia Dhofar 287B: A record of lunar volcanismMETEORITICS & PLANETARY SCIENCE, Issue 4 2003S. I. Demidova The present study is directed mainly at the breccia portion of this meteorite. This breccia consists of a variety of lithic clasts and mineral fragments set in a fine-grained matrix and minor impact melt. The majority of clasts and minerals appear to have been mainly derived from the low-Ti basalt suite, similar to that of Dho 287A. Very low-Ti (VLT) basalts are a minor lithology of the breccia. These are significantly lower in Mg# and slightly higher in Ti compared to Luna 24 and Apollo 17 VLT basalts. Picritic glasses constitute another minor component of the breccia and are compositionally similar to Apollo 15 green glasses. Dho 287B also contains abundant fragments of Mg-rich pyroxene and anorthite-rich plagioclase grains that are absent in the lithic clasts. Such fragments appear to have been derived from a coarse-grained, Mg#-rich, Na-poor lithology. A KREEP component is apparent in chemistry, but no highlands lithologies were identified. The Dho 287 basaltic lithologies cannot be explained by near-surface fractionation of a single parental magma. Instead, magma compositions are represented by a picritic glass; a low-Ti, Na-poor glass; and a low-Ti, Na-enriched source (similar to the Dho 287A parental melt). Compositional differences among parent melts could reflect inhomogeneity of the lunar mantle. Alternatively, the low-Ti, Na-poor, and Dho 287A parent melts could be of hybrid compositions, resulting from assimilation of KREEP by picritic magma. Thus, the Dho 287B breccia contains lithologies from multiple magmatic eruptions, which differed in composition, formational conditions, and cooling histories. Based on this study, the Dho 287 is inferred to have been ejected from a region located distal to highlands terrains, possibly from the western limb of the lunar nearside, dominated by mare basalts and KREEP-rich lithologies. [source] Polychromatic Light Similar to the Terrestrial Solar Spectrum Without its UV Component Stimulates DNA Synthesis in Human Peripheral Blood Lymphocytes In Vivo and In VitroPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 5 2006Natalya A. Zhevago ABSTRACT Immunosuppressive effects of the minor component of the terrestrial solar spectrum, UV radiation, have been substantiated over the past several years. This raises the question of what influence the dominant part of the solar spectrum,visible and IR light,would have on the human immune system. In the present randomized, placebo-controlled double-blind study a small area of the body surface of volunteers was irradiated with polychromatic light (480,3400 nm), simulating the significant part of the terrestial sunlight irradiance spectrum and its power density. An average 2.5-fold to three-fold increase in spontaneous and phytohemagglutinin-induced DNA synthesis in peripheral blood lymphocytes (Lym) was revealed at 0.5,24 h after irradiation at a therapeutic dose (12 J/cm2) in subjects with low preirradiation levels of both processes. The in vivo findings were echoed in parallel in vitro experiments, when blood drawn from the same subjects was directly irradiated (2.4 J/cm2), or when the irradiated blood was mixed 1:10 with nonirradiated autolo-gous blood to model events in the circulation following transcutaneous blood photomodification. Our data suggest that exposure of the human body to polychromatic visible + IR light may photomodify blood in the dermal vasculature of the irradiated area to lead to an immediate transfer of the light-induced effects to Lym of the entire circulating blood, which can result in modulation of Lym functional state at the systemic level. [source] Visualization and microscopic modeling of phase inversion during compoundingPOLYMER ENGINEERING & SCIENCE, Issue 8 2001R. Ratnagiri A detailed description of the sequence of deformation steps leading to phase inversion during compounding in a low-viscosity-ratio co-polyester/polyethylene blend is presented. Visualization using a glass window and sampling of the blend at different mixing times enabled identification of the intermediate morphologies of the major component en route to phase inversion. Based on these observations, a theoretical model is developed to predict the time to phase inversion. The model incorporates a simplified flow-field approximation and the calculation of strain imparted to the major component domains. A strain-based criterion for phase inversion is then proposed, which, in conjunction with the model, yields an explicit expression for the time to phase inversion during compounding, tP.I.. The model predictions are seen to be in good agreement with the increase of tP.I., on scaleup between two mixing bowls. The correct functional dependence of tP.I. on the nominal maximum-shear-rate is predicted. Using combination of pure drag and planar extensional flow, the model predictions are shown to be consistent with the observed dependence of tP.I. on the volume fraction of the minor component and the blend viscosity ratio. [source] Shipwrecks and founder effects: Divergent demographic histories reflected in Caribbean mtDNAAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2005Antonio Salas Abstract During the period of the Atlantic slave trade (15th,19th centuries), millions of people were forced to move from Africa to many American destinations, changing dramatically the human landscape of the Americas. Here, we analyze mitochondrial DNA from two different American populations with African ancestry, with hitherto unknown European and Native American components. On the basis of historical records, African-Americans from Chocó (Colombia) and the Garífunas (or "Black Carib") of Honduras are likely to have had very different demographic histories, with a significant founder effect in the formation of the latter. Both the common features and differences are reflected in their mtDNA composition. Both show a minor component (,16%) from Native Central/South Americans and a larger component (,84%) from sub-Saharan Africans. The latter component is very diverse in the African-Americans from Chocó, similar to that of sub-Saharan Africans, but much less so in the Garífunas, with several mtDNA types elevated to high frequency, suggesting the action of genetic drift. Am J Phys Anthropol, 2005. © 2005 Wiley-Liss, Inc. [source] Protein tyrosine phosphatase PTP1B is involved in neuroendocrine differentiation of prostate cancerTHE PROSTATE, Issue 11 2006Chengyu Wu Abstract BACKGROUND Prostate cancer (PC) contains a minor component of neuroendocrine (NE) cells that may stimulate androgen-independent growth of the tumor. The mechanism of neuroendocrine differentiation remains unknown. METHODS The expression of PTP1B, a protein tyrosine phosphatase, was studied in LNCaP cells induced to show neuroendocrine phenotype by androgen withdrawal. Wild-type PTP1B and its dominant-negative mutant were transfected into LNCaP cells to study their effects on neuroendocrine differentiation. In vivo expression of PTP1B in human prostate cancer was studied by immunohistochemistry. RESULTS Androgen withdrawal of LNCaP cells led to increased expression of PTP1B with a corresponding increase in its tyrosine phosphatase activity. Overexpression of PTP1B in LNCaP cells led to neuroendocrine differentiation while expression of its dominant-negative mutant inhibited neuroendocrine differentiation. Immunohistochemical study showed that PTP1B was exclusively expressed in neuroendocrine cells of human prostate cancer tissue. Conclusion Our findings suggest that PTP1B plays an important role in neuroendocrine differentiation, and therefore, may possibly be involved in the progression of prostate cancer. Prostate © 2006 Wiley-Liss, Inc. [source] Sterically shielded pyramidal amino groups in two 4,4,-(arylmethylene)bis(6-allyl-3-chloro-2-methylaniline) derivativesACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2009Maria C. Blanco 4,4,-(Phenylmethylene)bis(6-allyl-3-chloro-2-methylaniline), C27H28Cl2N2, (I), and 4,4,-(2-thienylmethylene)bis(6-allyl-3-chloro-2-methylaniline), C25H26Cl2N2S, (II), adopt similar molecular conformations, although the thienyl group in (II) exhibits orientational disorder over two sets of sites with occupancies of 0.614,(3) and 0.386,(3). The amino groups in both compounds are pyramidal. A single N,H...N hydrogen bond links the molecules of (I) into cyclic centrosymmetric dimers. Molecules of (II) are linked by an ordered C,H...,(arene) hydrogen bond to form cyclic centrosymmetric dimers, and these dimers are linked into statistically interrupted chains by a second C,H...,(arene) hydrogen bond involving a donor in the minor component of the disordered thienyl unit. [source] Conjugated linoleic acid isomers: Differences in metabolism and biological effectsBIOFACTORS, Issue 1 2009Itziar Churruca Abstract The term conjugated linoleic acid (CLA) refers to a mixture of linoleic acid positional and geometric isomers, characterized by having conjugated double bonds, not separated by a methylene group as in linoleic acid. CLA isomers appear as a minor component of the lipid fraction, found mainly in meat and dairy products from cows and sheep. The most abundant isomer is cis -9,trans -11, which represents up to 80% of total CLA in food. These isomers are metabolized in the body through different metabolic pathways, but important differences, that can have physiological consequences, are observed between the two main isomers. The trans -10,cis -12 isomer is more efficiently oxidized than the cis -9,trans -11 isomer, due to the position of its double bounds. Interest in CLA arose in its anticarcinogenic action but there is an increasing amount of specific scientific literature concerning the biological effects and properties of CLA. Numerous biological effects of CLA are due to the separate action of the most studied isomers, cis -9,trans -11 and trans -10,cis -12. It is also likely that some effects are induced and/or enhanced by these isomers acting synergistically. Although the cis -9,trans -11 isomer is mainly responsible for the anticarcinogenic effect, the trans -10,cis -12 isomer reduces body fat and it is referred as the most effective isomer affecting blood lipids. As far as insulin function is concerned, both isomers seem to be responsible for insulin resistance in humans. Finally, with regard to the immune system it is not clear whether individual isomers of CLA could act similarly or differently. © 2009 International Union of Biochemistry and Molecular Biology, Inc. [source] Conformations of Betanova in aqueous trifluoroethanol,BIOPOLYMERS, Issue 10 2010Danny P. Chagolla Abstract Conformations of the designed peptide Betanova in 42% trifluoroethanol/water (v/v) were explored. Circular dichroism (CD) observations provided no evidence for the presence of significant amounts of ,-structures in water, in TFE/water, or in ethanol/water. Nuclear magnetic resonance (NMR) diffusion experiments showed no significant difference in the hydrodynamic radius of the peptide in water and in 42% TFE/water. However, calculations indicated that the hydrodynamic radii of the triple-stranded ,-sheet, originally proposed for Betanova by Kortemme et al. (Science 1998, 281, 253-256), and a variety of partially folded forms of Betanova would be similar and likely could not be convincingly distinguished by diffusion experiments. Temperature coefficients (,,/,T) of the peptide NH chemical shifts are similar in water and 42% TFE/water, implying that most of these protons are highly solvent exposed in both solvents and likely do not participate in intramolecular hydrogen bonding interactions. Possible exceptions to this conclusion are the Lys9 and Lys15 residues, where a more positive coefficient may indicate that these residues are involved to some extent in local turn structures. Peptide proton,solvent fluorine intermolecular nuclear Overhauser effect (NOE)s at 25°C were consistent with the presence of a mixture of conformations, which could include the triple-stranded ,-sheet structure as a minor component. At 0°C, peptide-TFE NOEs indicated that TFE interacts strongly enough with many protons of Betanova that alcohol-peptide interactions persist for times of the order of nanoseconds, appreciably longer than the encounter time characteristic of mutual diffusion of TFE and the solute. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 893,903, 2010. [source] Molecular cloning and immunoglobulin E reactivity of a natural rubber latex lecithinase homologue, the major allergenic component of Hev b 4CLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2005E. Sunderasan Summary Background Hev b 4 is an allergenic natural rubber latex (NRL) protein complex that is reactive in skin prick tests and in vitro immunoassays. On SDS-polyacrylamide gel electrophoresis (SDS-PAGE), Hev b 4 is discerned predominantly at 53,55 kDa together with a 57 kDa minor component previously identified as a cyanogenic glucosidase. Of the 13 NRL allergens recognized by the International Union of Immunological Societies, the 53,55 kDa Hev b 4 major protein is the only candidate that lacks complete cDNA and protein sequence information. Objective We sought to clone the transcript encoding the Hev b 4 major protein, and characterize the native protein and its recombinant form in relation to IgE binding. Methods The 5,/3, rapid amplification of cDNA ends method was employed to obtain the complete cDNA of the Hev b 4 major protein. A recombinant form of the protein was over-expressed in Escherichia coli. The native Hev b 4 major protein was deglycosylated by trifluoromethane sulphonic acid. Western immunoblots of the native, deglycosylated and recombinant proteins were performed using both polyclonal antibodies and sera from latex-allergic patients. Results The cDNA encoding the Hev b 4 major protein was cloned. Its open reading frame matched lecithinases in the conserved domain database and contained 10 predicted glycosylation sites. Detection of glycans on the Hev b 4 lecithinase homologue confirmed it to be a glycoprotein. The deglycosylated lecithinase homologue was discerned at 40 kDa on SDS-PAGE, this being comparable to the 38.53 kDa mass predicted by its cDNA. Deglycosylation of the lecithinase homologue resulted in the loss of IgE recognition, although reactivity to polyclonal rabbit anti-Hev b 4 was retained. IgE from latex-allergic patients also failed to recognize the non-glycosylated E. coli recombinant lecithinase homologue. Conclusion The IgE epitopes of the Hev b 4 lecithinase homologue reside mainly in its carbohydrate moiety, which also account for the discrepancy between the observed molecular weight of the protein and the value calculated from its cDNA. [source] Identification of cyanobacteria and their toxigenicity in environmental samples by rapid molecular analysisENVIRONMENTAL TOXICOLOGY, Issue 6 2001Judith A. Baker Abstract We report molecular analyses which identify cyanobacterial strains present in environmental samples. These analyses do not require the isolation and culture of strains. Identification of cyanobacteria used the polymerase chain reaction (PCR), based on the phycocyanin operon. Differentiation was either by restriction endonuclease digestion (restriction fragment length polymorphisms) or sequencing of the PCR products. Identification was based on sequence homology of the intergenic spacer region (IGS) between the ,- and ,-phycocyanin subunits (PC-IGS) with database records. We have found that the length and sequence of the PC-IGS is capable of predicting the genus accurately, but not the species. Toxigenicity was determined with oligonucleotide probes for key steps in the microcystin toxin synthesis pathway. We have shown that it is possible to easily and routinely obtain PCR amplification products and differentiate the strains in bloom samples. The methods can detect even minor components in bloom samples, which may not be apparent on microscopic examination. Genetic probes for microcystin toxigenicity are effective on environmental samples, eliminating the need for isolation and culture of the organisms. The use of a suite of tests described here will allow water managers to determine the presence and the type of cyanobacteria and their microcystin toxigenicity. © 2001 John Wiley & Sons, Inc. Environ Toxicol 16: 472,482, 2001 [source] International conference on the healthy effect of virgin olive oilEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2005Summary 1Ageing represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, morbus Parkinson, Alzheime's disease, vascular dementia, cognitive decline, diabetes and cancer. 2Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decreases the risk of cardiovascular disease. 3The Mediterranean diet, rich in virgin olive oil, improves the major risk factors for cardiovascular disease, such as the lipoprotein profile, blood pressure, glucose metabolism and antithrombotic profile. Endothelial function, inflammation and oxidative stress are also positively modulated. Some of these effects are attributed to minor components of virgin olive oil. Therefore, the definition of the Mediterranean diet should include virgin olive oil. 4Different observational studies conducted in humans have shown that the intake of monounsaturated fat may be protective against age-related cognitive decline and Alzheimer's disease. 5Microconstituents from virgin olive oil are bioavailable in humans and have shown antioxidant properties and capacity to improve endothelial function. Furthermore they are also able to modify the haemostasis, showing antithrombotic properties. 6In countries where the populations fulfilled a typical Mediterranean diet, such as Spain, Greece and Italy, where virgin olive oil is the principal source of fat, cancer incidence rates are lower than in northern European countries. 7The protective effect of virgin olive oil can be most important in the first decades of life, which suggests that the dietetic benefit of virgin olive oil intake should be initiated before puberty, and maintained through life. 8The more recent studies consistently support that the Mediterranean diet, based in virgin olive oil, is compatible with a healthier ageing and increased longevity. However, despite the significant advances of the recent years, the final proof about the specific mechanisms and contributing role of the different components of virgin olive oil to its beneficial effects requires further investigations. [source] Quantification of free and esterified steryl glucosides in vegetable oils and biodieselEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 8 2009Florence Lacoste Dr. Abstract Steryl glucosides (SG) are minor components that dramatically modify the low temperature performance of fatty acid methyl esters (FAME) used as biodiesel. SG are naturally present in vegetable oils but they may also be the result of the transesterification of esterified steryl glucosides (ESG). These are present in vegetable oils at a level of a few hundred milligrams per kilogram, depending on the nature of the feedstock. We developed an analytical method to quantify SG and ESG in vegetable oils and in FAME. The purification of SG and ESG was performed by liquid chromatography on silica gel, and the analysis of the trimethylsilyl derivatives was achieved by gas chromatography and flame ionization detection. The filterability of biodiesel is affected when the SG content is higher than 20,mg/kg. Therefore, the sensitivity of this new method is adapted for this purpose since the quantification limit is 10,mg/kg of SG and ESG. The recoveries are acceptable, between 75% and 90% depending on the species and content, and the reproducibility relative standard deviation, evaluated at 10%, is comparable to other studies. [source] Optimization of industrial-scale deodorization of high-oleic sunflower oil via response surface methodologyEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 3 2008Vito Martin Abstract Optimization of industrial-scale deodorization of high-oleic sunflower oil (HOSO) via response surface methodology is presented in this study. The results of an experimental program conducted on an industrial-scale deodorizer were analyzed statistically. Predictive models were derived for each of the oil quality indicators (QI) in dependence on the studied variable deodorization process parameters. The deodorization behavior of some minor components was analyzed on a pilot-scale deodorizer. For comparison, a similar experimental program was also performed on the laboratory-scale. The results of this study demonstrate that optimization of the deodorization process requires a suitable compromise between often mutually opposing demands dictated by different oil QI. The production of HOSO with top-quality organoleptic and nutritional values (high tocopherol and phytosterol contents and low free and trans fatty acid contents) and high oxidative stability demands deodorization temperatures in the range between 220 and 235,°C and a total sparge steam above 2.0% (wt/wt in oil). The response surface methodology provides the tools needed to identify the optimum deodorization process conditions. However, the laboratory-scale experiments, while showing similar response characteristics of QI in dependence on the process parameters and thus helpful as a guide, are of limited value in the optimization of an industrial-scale operation. [source] Mass spectrometry study of ecto-5,-nucleotidase from bull seminal plasmaFEBS JOURNAL, Issue 16 2000Carlo Fini The structure of ecto-5,-nucleotidase from bull seminal plasma, containing a glycosyl-phosphatidylinositol anchor, was studied using mass spectrometry. MALDI-MS analysis of intact protein indicated a mass of 65 568.2 Da for the monomeric form, and it also showed a heterogeneous population of glycoforms with the glycosidic moiety accounting for ,,6000 Da. MALDI-MS analysis showed that Asn53, Asn311, Asn333 and Asn403 were four sites of N -glycosylation. GC-MS analysis provided information on the glycosidic structures linked to the four asparagines. Asn53, Asn311 and Asn333 were linked to high-mannose saccharide chains, whereas the glycan chains linked to Asn403 contained a heterogeneous mixture of oligosaccharides, the high-mannose type structure being the most abundant and hybrid or complex type glycans being minor components. By combining enzymatic and/or chemical hydrolysis with GC-MS analysis, detailed characterization of the glycosyl-phpsphatidylinositol anchor was obtained. MALDI spectral analysis indicated that the glycosyl-phosphatidylinositol core contained EtN(P)Man3GlcNH2 -myo-inositol(P)-glycerol, principally modified by stearoyl and palmitoyl residues or by stearoyl and myristoyl residues to a minor extent. Moreover, 1-palmitoylglycerol and 1-stearoylglycerol outweighed 2-palmitoylglycerol and 2-stearoylglycerol. The combination of chemical and enzymatic digestions of the protein with the mass spectral analysis yielded a complete pattern of S,S bridges. The protein does not contain free thiols and its eight cysteines are linked by intramolecular disulfide bonds, the pairs being: Cys51,Cys57, Cys353,Cys358, Cys365,Cys387 and Cys476,Cys479. This work resolves details of the structure of ecto-5,-nucleotidase, with particular regard to the localization and composition of the glycidic moiety, number and localization of the disulfide bridges and characterization of the glycosyl-phosphatidylinositol anchor. [source] | ||||||||||||||||||||||||||||||||||||||||