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Sample records for enrichment selectively increases

  1. Nutrient Enrichment Increases Mortality of Mangroves

    PubMed Central

    Lovelock, Catherine E.; Ball, Marilyn C.; Martin, Katherine C.; C. Feller, Ilka

    2009-01-01

    Nutrient enrichment of the coastal zone places intense pressure on marine communities. Previous studies have shown that growth of intertidal mangrove forests is accelerated with enhanced nutrient availability. However, nutrient enrichment favours growth of shoots relative to roots, thus enhancing growth rates but increasing vulnerability to environmental stresses that adversely affect plant water relations. Two such stresses are high salinity and low humidity, both of which require greater investment in roots to meet the demands for water by the shoots. Here we present data from a global network of sites that documents enhanced mortality of mangroves with experimental nutrient enrichment at sites where high sediment salinity was coincident with low rainfall and low humidity. Thus the benefits of increased mangrove growth in response to coastal eutrophication is offset by the costs of decreased resilience due to mortality during drought, with mortality increasing with soil water salinity along climatic gradients. PMID:19440554

  2. Enrichment of phosphorylated peptides and proteins by selective precipitation methods.

    PubMed

    Rainer, Matthias; Bonn, Günther K

    2015-01-01

    Protein phosphorylation is one of the most prominent post-translational modifications involved in the regulation of cellular processes. Fundamental understanding of biological processes requires appropriate bioanalytical methods for selectively enriching phosphorylated peptides and proteins. Most of the commonly applied enrichment approaches include chromatographic materials including Fe(3+)-immobilized metal-ion affinity chromatography or metal oxides. In the last years, the introduction of several non-chromatographic isolation technologies has increasingly attracted the interest of many scientists. Such approaches are based on the selective precipitation of phosphorylated peptides and proteins by applying various metal cations. The excellent performance of precipitation-based enrichment methods can be explained by the absence of any stationary phase, resin or sorbent, which usually leads to unspecific binding. This review provides an overview of recently published methods for the selective precipitation of phosphorylated peptides and proteins. PMID:25587840

  3. Selective enrichment and desalting of hydrophilic peptides using graphene oxide.

    PubMed

    Jiang, Miao; Qi, Linyu; Liu, Peiru; Wang, Zijun; Duan, Zhigui; Wang, Ying; Liu, Zhonghua; Chen, Ping

    2016-08-01

    The wide variety and low abundance of peptides in tissue brought great difficulties to the separation and identification of peptides, which is not in favor of the development of peptidomics. RP-HPLC, which could purify small molecules based on their hydrophobicity, has been widely used in the separation and enrichment of peptide due to its fast, good reproducibility and high resolution. However, RP-HPLC requires the instrument and expensive C18 column and its sample capacity is also limited. Recently, graphene oxide has been applied to the adsorption of amino acids. However, the enrichment efficiency and selectivity of graphene oxide for peptides remain unclear. In this study, the adsorption efficiency and selectivity of graphene oxide and RP-C18 matrix were compared on trypsinized α-actin and also on tissue extracts from pituitary gland and hippocampus. For α-actin, there exhibit similar elution peaks for total trypsinized products and those adsorpted by GO and C18 matrix. But peptides adsorbed by GO showed the higher hydrophilic peaks than which adsorbed by C18 matrix. The resulted RP-HPLC profile showed that most of peptides enriched by graphene oxide were eluted at low concentration of organic solvent, while peptides adsorbed by RP-C18 matrix were mostly eluted at relatively high concentration. Moreover, mass spectrometry analysis suggested that, in pituitary sample, there were 495 peptides enriched by graphene oxide, 447 peptides enriched by RP-C18 matrix while in hippocampus sample 333 and 243 peptides respectively. The GRAVY value analysis suggested that the graphene oxide has a stronger adsorption for highly hydrophilic peptides compared to the RP-C18 matrix. Furthermore, the combination of these two methods could notably increase the number of identification peptides but also the number of predicted protein precursors. Our study provided a new thought to the role of graphene oxide during the enrichment of peptides from tissue which should be useful for

  4. Selective enrichment of damaged DNA molecules for ancient genome sequencing

    PubMed Central

    2014-01-01

    Contamination by present-day human and microbial DNA is one of the major hindrances for large-scale genomic studies using ancient biological material. We describe a new molecular method, U selection, which exploits one of the most distinctive features of ancient DNA—the presence of deoxyuracils—for selective enrichment of endogenous DNA against a complex background of contamination during DNA library preparation. By applying the method to Neanderthal DNA extracts that are heavily contaminated with present-day human DNA, we show that the fraction of useful sequence information increases ∼10-fold and that the resulting sequences are more efficiently depleted of human contamination than when using purely computational approaches. Furthermore, we show that U selection can lead to a four- to fivefold increase in the proportion of endogenous DNA sequences relative to those of microbial contaminants in some samples. U selection may thus help to lower the costs for ancient genome sequencing of nonhuman samples also. PMID:25081630

  5. Loss of Environmental Enrichment Increases Vulnerability to Cocaine Addiction

    PubMed Central

    Nader, Joëlle; Claudia, Chauvet; Rawas, Rana El; Favot, Laure; Jaber, Mohamed; Thiriet, Nathalie; Solinas, Marcello

    2012-01-01

    Life experiences, especially during critical periods of maturation, such as adolescence, can dramatically affect vulnerability to diseases at adulthood. Early exposure to positive environmental conditions such as environmental enrichment (EE) has been shown to reduce the occurrence and the intensity of neurological and psychiatric disorders including drug addiction. However, whether or not exposure to EE during early stages of life would protect from addiction when, at adulthood, individuals may find themselves in non-enriched conditions has not been investigated. Here we show that switching mice from EE to non-enriched standard environments not only results in the loss of the preventive effects of EE but also increases the rewarding effects of cocaine. This enhanced vulnerability is associated with emotional distress and with increased levels in the mRNA levels of corticotropin releasing factor (CRF) in the bed nucleus of the stria terminalis (BNST), as well as with increases in CREB phosphorylation in the BNST and in the shell of the nucleus accumbens. The increased sensitivity to the rewarding effects of cocaine is completely blocked by the CRF antagonist antalarmin, confirming a major role of the CRF system in the negative consequences of this environmental switch. These results indicate that positive life conditions during early stages of life, if they are not maintained at adulthood, may have negative emotional consequences and increase the risks to develop drug addiction. PMID:22334125

  6. Odour enrichment increases adult-born dopaminergic neurons in the mouse olfactory bulb.

    PubMed

    Bonzano, Sara; Bovetti, Serena; Fasolo, Aldo; Peretto, Paolo; De Marchis, Silvia

    2014-11-01

    The olfactory bulb (OB) is the first brain region involved in the processing of olfactory information. In adult mice, the OB is highly plastic, undergoing cellular/molecular dynamic changes that are modulated by sensory experience. Odour deprivation induces down-regulation of tyrosine hydroxylase (TH) expression in OB dopaminergic interneurons located in the glomerular layer (GL), resulting in decreased dopamine in the OB. Although the effect of sensory deprivation is well established, little is known about the influence of odour enrichment on dopaminergic cells. Here we report that prolonged odour enrichment on C57BL/6J strain mice selectively increases TH-immunopositive cells in the GL by nearly 20%. Following odour enrichment on TH-green fluorescent protein (GFP) transgenic mice, in which GFP identified both mature TH-positive cells and putative immature dopaminergic cells expressing TH mRNA but not TH protein, we found a similar 20% increase in GFP-expressing cells, with no changes in the ratio between TH-positive and TH-negative cells. These data suggest that enriched conditions induce an expansion in the whole dopaminergic lineage. Accordingly, by using 5-bromo-2-deoxyuridine injections to label adult-generated cells in the GL of TH-GFP mice, we found an increase in the percentage of 5-bromo-2-deoxyuridine-positive dopaminergic cells in enriched compared with control conditions, whereas no differences were found for calretinin- and calbindin-positive subtypes. Strikingly, the fraction of newborn cells among the dopaminergic population doubled in enriched conditions. On the whole, our results demonstrate that odour enrichment drives increased integration of adult-generated dopaminergic cells that could be critical to adapt the OB circuits to the environmental incoming information. PMID:25216299

  7. Increased predation of nutrient-enriched aposematic prey.

    PubMed

    Halpin, Christina G; Skelhorn, John; Rowe, Candy

    2014-04-22

    Avian predators readily learn to associate the warning coloration of aposematic prey with the toxic effects of ingesting them, but they do not necessarily exclude aposematic prey from their diets. By eating aposematic prey 'educated' predators are thought to be trading-off the benefits of gaining nutrients with the costs of eating toxins. However, while we know that the toxin content of aposematic prey affects the foraging decisions made by avian predators, the extent to which the nutritional content of toxic prey affects predators' decisions to eat them remains to be tested. Here, we show that European starlings (Sturnus vulgaris) increase their intake of a toxic prey type when the nutritional content is artificially increased, and decrease their intake when nutritional enrichment is ceased. This clearly demonstrates that birds can detect the nutritional content of toxic prey by post-ingestive feedback, and use this information in their foraging decisions, raising new perspectives on the evolution of prey defences. Nutritional differences between individuals could result in equally toxic prey being unequally predated, and might explain why some species undergo ontogenetic shifts in defence strategies. Furthermore, the nutritional value of prey will likely have a significant impact on the evolutionary dynamics of mimicry systems. PMID:24598424

  8. Increased predation of nutrient-enriched aposematic prey

    PubMed Central

    Halpin, Christina G.; Skelhorn, John; Rowe, Candy

    2014-01-01

    Avian predators readily learn to associate the warning coloration of aposematic prey with the toxic effects of ingesting them, but they do not necessarily exclude aposematic prey from their diets. By eating aposematic prey ‘educated’ predators are thought to be trading-off the benefits of gaining nutrients with the costs of eating toxins. However, while we know that the toxin content of aposematic prey affects the foraging decisions made by avian predators, the extent to which the nutritional content of toxic prey affects predators' decisions to eat them remains to be tested. Here, we show that European starlings (Sturnus vulgaris) increase their intake of a toxic prey type when the nutritional content is artificially increased, and decrease their intake when nutritional enrichment is ceased. This clearly demonstrates that birds can detect the nutritional content of toxic prey by post-ingestive feedback, and use this information in their foraging decisions, raising new perspectives on the evolution of prey defences. Nutritional differences between individuals could result in equally toxic prey being unequally predated, and might explain why some species undergo ontogenetic shifts in defence strategies. Furthermore, the nutritional value of prey will likely have a significant impact on the evolutionary dynamics of mimicry systems. PMID:24598424

  9. Non-selective and selective enrichment media for the recovery of Clostridium difficile from chopped beef.

    PubMed

    Chai, Changhoon; Lee, Kyung-Soo; Lee, Dayoung; Lee, Soyeon; Oh, Se-Wook

    2015-02-01

    Clostridium difficile exists within the intestines of animals and in meat products. Enrichment of C. difficile in an appropriate medium is necessary for the detection of C. difficile in meat products. Non-selective media (brain heart infusion medium [TBHI] and cooked meat medium containing sodium taurocholate [TCM]) and selective media (cycloserine-cefoxitin-fructose medium [TCCFB] and C. difficile moxalactam-norfloxacin medium containing antibiotics and sodium taurocholate [TCDMN]) can be used to enrich C. difficile. This study aimed to evaluate non-selective and selective enrichment media for the recovery of C. difficile from beef specimens. The efficiency of the enrichment media was investigated on the basis of the recovery frequency of C. difficile from beef specimens inoculated with C. difficile. The beef specimens were inherently contaminated with bacteria (around 10(4)CFUg(-1)), and further inoculated with C. difficile (around 10(0)CFUg(-1)). The antibiotics in TCCFB and TCDMN adversely affected C. difficile growth. The bacteria inherent to these specimens exhibited resistance to antibiotics and grew during the enrichment of C. difficile-inoculated chopped beef in TCCFB and TCDMN, which hindered the recovery of C. difficile. The frequency of recovery of C. difficile from beef specimens in TCM was higher than that from any other enrichment medium. PMID:25499549

  10. Increasing the performance of tritium analysis by electrolytic enrichment.

    PubMed

    Groning, M; Auer, R; Brummer, D; Jaklitsch, M; Sambandam, C; Tanweer, A; Tatzber, H

    2009-06-01

    Several improvements are described for the existing tritium enrichment system at the Isotope Hydrology Laboratory of the International Atomic Energy Agency for processing natural water samples. The improvements include a simple method for pretreatment of electrolytic cells to ensure a high tritium separation factor, an improved design of the exhaust system for explosive gases, and a vacuum distillation line for faster initial preparation of water samples for electrolytic enrichment and for tritium analysis. Achievements included the reduction of variation of individual enrichment parameters of all cells to less than 1% and an improvement of 50% of the stability of the background mean. It resulted in an improved detection limit of less than 0.4 TU (at 2s), important for application of tritium measurements in the future at low concentration levels, and resulted in measurement precisions of+/-0.2 TU and+/-0.15 TU for liquid scintillation counting and for gas proportional counting, respectively. PMID:20183225

  11. Environmental enrichment effects on the neurobehavioral profile of selective outbred trait anxiety rats

    PubMed Central

    Ravenelle, Rebecca; Byrnes, Elizabeth M.; Byrnes, John J.; McInnis, Christine; Park, Jin Ho; Donaldson, S. Tiffany

    2013-01-01

    Environmental enrichment attenuates the response to psychostimulants and has been shown to reduce both anxiety and stress-related behaviors. Since stress is a major vulnerability factor for addiction, we investigated whether enrichment could reverse stress profiles in high anxious rats as well as reduce their amphetamine sensitivity. Using selectively-bred high and low anxiety males (filial 3) from enriched, social or isolated environments, we tested elevated plus maze exploration, novelty place preference and amphetamine (AMPH; 0.5 mg/kg, IP)-induced hyperactivity. We measured plasma corticosterone (CORT) response after forced novel object exposure, phosphorylation of the tropomyosin-related kinase B receptor (pTrkB) in the hippocampus and striatum, and dopamine (D2) receptor mRNA levels in the striatum and nucleus accumbens. Results indicate that high anxiety animals reared in social or enriched environments spent more time on open arms of the EPM while low anxiety animals raised in enriched environments spent more time on open arms when compared to either isolated or social groups. There were no group differences or interactions found for novelty place preference. Enriched environments decreased the response to AMPH and stress-induced CORT regardless of trait but selectively decreased pTrkB and increased D2 mRNA levels in high anxiety animals. The results suggest that selectively-bred trait anxiety rats show state anxiety that is influenced by rearing environments, and D2 protein levels and BDNF/TrkB signaling may differentially contribute to integrating these effects. PMID:23727174

  12. Semisolid selective-motility enrichment medium for isolation of salmonellae from fecal specimens.

    PubMed Central

    Goossens, H; Wauters, G; de Boeck, M; Janssens, M; Butzler, J P

    1984-01-01

    A semisolid selective-motility enrichment medium for the isolation of salmonellae from fecal specimens was developed which was based on Rappaport enrichment broth. During a 7-year period more than 30,000 stool samples were tested. The medium showed a high specificity (95.1%) and sensitivity (80.3%) when compared with MacConkey agar, SS agar, and brilliant green agar (after Selenite-F Enrichment [BBL Microbiology Systems]). Furthermore, our isolation rate of Salmonella species from fecal samples showed an increase of 22.3% when this semisolid medium was added to the routine culture media. Growth could easily be interpreted. The medium has a bias toward the isolation of Salmonella paratyphi B, but it is unsatisfactory for detecting the nonmotile strains Salmonella typhi and S. paratyphi A. Images PMID:6470105

  13. Increased functional protein expression using nucleotide sequence features enriched in highly expressed genes in zebrafish

    PubMed Central

    Horstick, Eric J.; Jordan, Diana C.; Bergeron, Sadie A.; Tabor, Kathryn M.; Serpe, Mihaela; Feldman, Benjamin; Burgess, Harold A.

    2015-01-01

    Many genetic manipulations are limited by difficulty in obtaining adequate levels of protein expression. Bioinformatic and experimental studies have identified nucleotide sequence features that may increase expression, however it is difficult to assess the relative influence of these features. Zebrafish embryos are rapidly injected with calibrated doses of mRNA, enabling the effects of multiple sequence changes to be compared in vivo. Using RNAseq and microarray data, we identified a set of genes that are highly expressed in zebrafish embryos and systematically analyzed for enrichment of sequence features correlated with levels of protein expression. We then tested enriched features by embryo microinjection and functional tests of multiple protein reporters. Codon selection, releasing factor recognition sequence and specific introns and 3′ untranslated regions each increased protein expression between 1.5- and 3-fold. These results suggested principles for increasing protein yield in zebrafish through biomolecular engineering. We implemented these principles for rational gene design in software for codon selection (CodonZ) and plasmid vectors incorporating the most active non-coding elements. Rational gene design thus significantly boosts expression in zebrafish, and a similar approach will likely elevate expression in other animal models. PMID:25628360

  14. Comparison of analytical values for enrichment nutrients in selected grain products to federal enrichment standards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enriched grain products are required to have iron, thiamin, riboflavin, niacin, and folic acid added at specified levels (minimum and maximum) according to the U.S. Code of Federal Regulations (CFR). To provide up-to-date values for the USDA National Nutrient Database for Standard Reference, enriche...

  15. Selective Recovery of Enriched Uranium from Inorganic Wastes

    SciTech Connect

    Kimura, R. T.

    2003-02-26

    Uranium as U(IV) and U(VI) can be selectively recovered from liquids and sludge containing metal precipitates, inorganic salts, sand and silt fines, debris, other contaminants, and slimes, which are very difficult to de-water. Chemical processes such as fuel manufacturing and uranium mining generate enriched and natural uranium-bearing wastes. This patented Framatome ANP (FANP) uranium recovery process reduces uranium losses, significantly offsets waste disposal costs, produces a solid waste that meets mixed-waste disposal requirements, and does not generate metal-contaminated liquids. At the head end of the process is a floating dredge that retrieves liquids, sludge, and slimes in the form of a slurry directly from the floor of a lined surface impoundment (lagoon). The slurry is transferred to and mixed in a feed tank with a turbine mixer and re-circulated to further break down the particles and enhance dissolution of uranium. This process uses direct steam injection and sodium hypochlorite addition to oxidize and dissolves any U(IV). Cellulose is added as a non-reactive filter aid to help filter slimes by giving body to the slurry. The slurry is pumped into a large recessed-chamber filter press then de-watered by a pressure cycle-controlled double-diaphragm pump. U(VI) captured in the filtrate from this process is then precipitated by conversion to U(IV) in another Framatome ANP-patented process which uses a strong reducing agent to crystallize and settle the U(IV) product. The product is then dewatered in a small filter press. To-date, over 3,000 Kgs of U at 3% U-235 enrichment were recovered from a 8100 m2 hypalon-lined surface impoundment which contained about 10,220 m3 of liquids and about 757 m3 of sludge. A total of 2,175 drums (0.208 m3 or 55 gallon each) of solid mixed-wastes have been packaged, shipped, and disposed. In addition, 9463 m3 of low-U liquids at <0.001 KgU/m3 were also further processed and disposed.

  16. Enhanced Control of PWR Primary Coolant Water Chemistry Using Selective Separation Systems for Recovery and Recycle of Enriched Boric Acid

    SciTech Connect

    Ken Czerwinski; Charels Yeamans; Don Olander; Kenneth Raymond; Norman Schroeder; Thomas Robison; Bryan Carlson; Barbara Smit; Pat Robinson

    2006-02-28

    The objective of this project is to develop systems that will allow for increased nuclear energy production through the use of enriched fuels. The developed systems will allow for the efficient and selective recover of selected isotopes that are additives to power water reactors' primary coolant chemistry for suppression of corrosion attack on reactor materials.

  17. Enriched environment increases the myelinated nerve fibers of aged rat corpus callosum.

    PubMed

    Zhao, Yuan-Yu; Shi, Xiao-Yan; Qiu, Xuan; Lu, Wei; Yang, Shu; Li, Chen; Chen, Lin; Zhang, Lei; Cheng, Guo-Hua; Tang, Yong

    2012-06-01

    In this study, the effect of enriched environment (EE) on the spatial learning of aged rats was examined, and then the effects of EE on the aged corpus callosum (CC) were investigated by means of the modern stereological methods. We found that EE significantly improved the spatial learning of aged rats. The CC volume, the total volume of the myelinated fibers and total volume of the myelin sheaths in the CC, the total length of the myelinated fibers in the CC of enriched rats were significantly increased when compared to standard rats. The increase of the myelinated fibers in enriched rat CC might provide one of the structural bases for the enrichment-related improvement of the spatial learning. This study provided, to the best of our knowledge, the first evidence of environmental enrichment-induced increases of the CC and the myelinated fibers in the CC of aged rats. PMID:22431229

  18. Deuterium enrichment by selective photoinduced dissociation of a multihalogenated organic compound

    DOEpatents

    Marling, John B.; Herman, Irving P.

    1981-01-01

    A method for deuterium enrichment by photoinduced dissociation which uses as the deuterium source a multihalogenated organic compound selected from the group consisting of a dihalomethane, a trihalomethane, a 1,2-dihaloethene, a trihaloethene, a tetrahaloethane and a pentahaloethane. The multihalogenated organic compound is subjected to intense infrared radiation at a preselected wavelength to selectively excite and thereby induce dissociation of substantially only those molecules containing deuterium to provide a deuterium enriched dissociation product. The deuterium enriched product may be combusted with oxygen to provide deuterium enriched water. The deuterium depleted undissociated molecules may be redeuterated by treatment with a deuterium source such as water.

  19. Selective enrichment of commensal gut bacteria protects against Citrobacter rodentium-induced colitis.

    PubMed

    Vong, Linda; Pinnell, Lee J; Määttänen, Pekka; Yeung, C William; Lurz, Eberhard; Sherman, Philip M

    2015-08-01

    The intestinal microbiota plays a key role in shaping the host immune system. Perturbation of gut microbial composition, termed dysbiosis, is associated with an increased susceptibility to intestinal pathogens and is a hallmark of a number of inflammatory, metabolic, and infectious diseases. The prospect of mining the commensal gut microbiota for bacterial strains that can impact immune function represents an attractive strategy to counteract dysbiosis and resulting disease. In this study, we show that selective enrichment of commensal gut lactobacilli protects against the murine pathogen Citrobacter rodentium, a well-characterized model of enteropathogenic and enterohemorrhagic Escherichia coli infection. The lactobacilli-enriched bacterial culture prevented the expansion of Gammaproteobacteria and Actinobacteria and was associated with improved indexes of epithelial barrier function (dextran flux), transmissible crypt hyperplasia, and tissue inflammatory cytokine levels. Moreover, cultivation of gut bacteria from Citrobacter rodentium-infected mice reveals the differential capacity of bacterial subsets to mobilize neutrophil oxidative burst and initiate the formation of weblike neutrophil extracellular traps. Our findings highlight the beneficial effects of a lactobacilli-enriched commensal gut microenvironment and, in the context of an intestinal barrier breach, the ability of neutrophils to immobilize both commensal and pathogenic bacteria. PMID:26067845

  20. Enrichment of circulating melanoma cells (CMCs) using negative selection from patients with metastatic melanoma

    PubMed Central

    Joshi, Powrnima; Jacobs, Barbara; Derakhshan, Adeeb; Moore, Lee R.; Elson, Paul; Triozzi, Pierre L.; Borden, Ernest; Zborowski, Maciej

    2014-01-01

    Circulating tumor cells have emerged as prognostic biomarkers in the treatment of metastatic cancers of epithelial origins viz., breast, colorectal and prostate. These tumors express Epithelial Cell Adhesion Molecule (EpCAM) on their cell surface which is used as an antigen for immunoaffinity capture. However, EpCAM capture technologies are of limited utility for non-epithelial cancers such as melanoma. We report a method to enrich Circulating Melanoma Cells (CMCs) that does not presuppose malignant cell characteristics. CMCs were enriched by centrifugation of blood samples from healthy (N = 10) and patient (N = 11) donors, followed by RBC lysis and immunomagnetic depletion of CD45-positive leukocytes in a specialized magnetic separator. CMCs were identified by immunocytochemistry using Melan-A or S100B as melanoma markers and enumerated using automated microscopy image analyses. Separation was optimized for maximum sensitivity and recovery of CMCs. Our results indicate large number of CMCs in Stage IV melanoma patients. Analysis of survival suggested a trend toward decreased survival with increased number of CMCs. Moreover, melanoma-associated miRs were found to be higher in CMC-enriched fractions in two patients when compared with the unseparated samples, validating this method as applicable for molecular analyses. Negative selection is a promising approach for isolation of CMCs and other EpCAM -negative CTCs, and is amenable to molecular analysis of CMCs. Further studies are required to validate its efficacy at capturing specific circulating cells for genomic analysis, and xenograft studies. PMID:24811334

  1. Proteomic profiling of maize opaque endosperm mutants reveals selective accumulation of lysine-enriched proteins

    PubMed Central

    Morton, Kyla J.; Jia, Shangang; Zhang, Chi; Holding, David R.

    2016-01-01

    Reduced prolamin (zein) accumulation and defective endoplasmic reticulum (ER) body formation occurs in maize opaque endosperm mutants opaque2 (o2), floury2 (fl2), defective endosperm*B30 (DeB30), and Mucronate (Mc), whereas other opaque mutants such as opaque1 (o1) and floury1 (fl1) are normal in these regards. This suggests that other factors contribute to kernel texture. A liquid chromatography approach coupled with tandem mass spectrometry (LC-MS/MS) proteomics was used to compare non-zein proteins of nearly isogenic opaque endosperm mutants. In total, 2762 proteins were identified that were enriched for biological processes such as protein transport and folding, amino acid biosynthesis, and proteolysis. Principal component analysis and pathway enrichment suggested that the mutants partitioned into three groups: (i) Mc, DeB30, fl2 and o2; (ii) o1; and (iii) fl1. Indicator species analysis revealed mutant-specific proteins, and highlighted ER secretory pathway components that were enriched in selected groups of mutants. The most significantly changed proteins were related to stress or defense and zein partitioning into the soluble fraction for Mc, DeB30, o1, and fl1 specifically. In silico dissection of the most significantly changed proteins revealed novel qualitative changes in lysine abundance contributing to the overall lysine increase and the nutritional rebalancing of the o2 and fl2 endosperm. PMID:26712829

  2. Selective enrichment of STRs for applications in forensic human identification.

    PubMed

    Gadipally, Sreeja R; Sarkar, Anujit; Nandineni, Madhusudan R

    2015-08-01

    Forensic human identification (HID) is currently based on determining repeat length polymorphisms located in short tandem repeat regions in the human genome. Despite the great progress made in the area of multiplex PCR-based approaches, limitations associated with challenging forensic samples such as DNA degradation, cooccurrence of inhabited microbial DNA and PCR inhibitors significantly affect the success rate of human DNA profiling. We have developed a sequence-specific pre-PCR STR enrichment method and evaluated its efficacy using DNA samples doped with various contaminants in view of its application on compromised forensic samples. This strategy has enabled us to generate complete and reproducible DNA profiles from samples doped with fivefold excess of nonhuman DNA and three to fourfold excess of various potent PCR inhibitors than that is claimed to be tolerated by some of the widely used commercial multiplex STR kits, from as little as two nanograms of degraded human DNA. The "hybrid capture"-based STR enrichment strategy described in this study is easily adaptable and offers a sensitive, efficient, and economical approach for successful human DNA profiling from compromised and recalcitrant forensic samples that are usually encountered in mass disaster incidents and missing persons' identifications. PMID:25959308

  3. Metal affinity enrichment increases the range and depth of proteome identification for extracellular microbial proteins

    SciTech Connect

    Wheeler, Korin; Erickson, Brian K; Mueller, Ryan; Singer, Steven; Verberkmoes, Nathan C; Hwang, Mona; Thelen, Michael P.; Hettich, Robert {Bob} L

    2012-01-01

    Many key proteins, such as those involved in cellular signaling or transcription, are difficult to measure in microbial proteomic experiments due to the interfering presence of more abundant, dominant proteins. In an effort to enhance the identification of previously undetected proteins, as well as provide a methodology for selective enrichment, we evaluated and optimized immobilized metal affinity chromatography (IMAC) coupled with mass spectrometric characterization of extracellular proteins from an extremophilic microbial community. Seven different metals were tested for IMAC enrichment. The combined results added 20% greater proteomic depth to the extracellular proteome. Although this IMAC enrichment could not be conducted at the physiological pH of the environmental system, this approach did yield a reproducible and specific enrichment of groups of proteins with functions potentially vital to the community, thereby providing a more extensive biochemical characterization. Notably, 40 unknown proteins previously annotated as hypothetical were enriched and identified for the first time. Examples of identified proteins includes a predicted TonB signal sensing protein homologous to other known TonB proteins and a protein with a COXG domain previously identified in many chemolithoautotrophic microbes as having a function in the oxidation of CO.

  4. LDL particle core enrichment in cholesteryl oleate increases proteoglycan binding and promotes atherosclerosis[S

    PubMed Central

    Melchior, John T.; Sawyer, Janet K.; Kelley, Kathryn L.; Shah, Ramesh; Wilson, Martha D.; Hantgan, Roy R.; Rudel, Lawrence L.

    2013-01-01

    Several studies in humans and animals suggest that LDL particle core enrichment in cholesteryl oleate (CO) is associated with increased atherosclerosis. Diet enrichment with MUFAs enhances LDL CO content. Steroyl O-acyltransferase 2 (SOAT2) is the enzyme that catalyzes the synthesis of much of the CO found in LDL, and gene deletion of SOAT2 minimizes CO in LDL and protects against atherosclerosis. The purpose of this study was to test the hypothesis that the increased atherosclerosis associated with LDL core enrichment in CO results from an increased affinity of the LDL particle for arterial proteoglycans. ApoB-100-only Ldlr−/− mice with and without Soat2 gene deletions were fed diets enriched in either cis-MUFA or n-3 PUFA, and LDL particles were isolated. LDL:proteogylcan binding was measured using surface plasmon resonance. Particles with higher CO content consistently bound with higher affinity to human biglycan and the amount of binding was shown to be proportional to the extent of atherosclerosis of the LDL donor mice. The data strongly support the thesis that atherosclerosis was induced through enhanced proteoglycan binding of LDL resulting from LDL core CO enrichment. PMID:23804810

  5. Evaluation of culture media for selective enrichment and isolation of Salmonella in seafood.

    PubMed

    Kumar, Rakesh; Surendran, Poothuvallil K; Thampuran, Nirmala

    2010-01-01

    Seafood, including fish, shrimp, clam, crab, mussel, oyster, lobster, squid, octopus, and cuttlefish samples, was used to compare the recovery of Salmonella serovars by different selective enrichment and isolation media. The samples were selectively enriched in Rappaport-Vassiliadis (RV) broth and tetrathionate broth (TT), followed by selective isolation on Hektoen enteric (HE) agar, xylose lysine desoxycholate (XLD) agar, bismuth sulfite (BS) agar, and Brilliant Green (BG) agar media. Of 443 seafood samples analyzed, 108 were found to be contaminated with Salmonella. The role of selective enrichment in Salmonella spp. recovery with RV medium was distinctly high (70%) compared to TT broth (30%). The selective enrichment in RV broth followed by selective isolation on XLD, HE, BS, and BG agar recovered Salmonella at levels of 56, 41, 28, and 16%, respectively. Similarly, after enrichment in TT broth, XLD and HE agars recovered 27 and 23% respectively. The recovery of Salmonella with enrichment in TT followed by isolation on BS and BG was abysmally low at 4.6 and 5%, respectively. There was no significant difference (P > 0.05) in the recovery of Salmonella using the combinations of XLD and HE media with selective enrichment in RV broth. However, performance difference (P < 0.05) was observed in the recovery when BS and BG with RV, and XLD, HE, BS, and BG agars with TT broth were used. The present study showed that the combination of RV with XLD was the most efficient media for isolation of Salmonella from seafood when compared to other isolation media combinations. PMID:21140659

  6. The Research of Membrane-sorption System with Increased Pressure Stream for Enriching Air with Oxygen

    NASA Astrophysics Data System (ADS)

    Korolev, M. V.; Laguntsov, N. I.; Kurchatov, I. M.

    Numerical study of single-hybrid membrane-sorption air separation system for enriching the air with oxygen were conducted. The effectiveness of such a system was analyzed, depending on selective sorbents and membranes under specified pressure ratio. A comparison of various modes membrane sorption system was done. The conclusion regarding the choice of the membrane and a sorbent for the system with a pressurized product stream was drawn.

  7. Selective Enrichment of a Methanol-Utilizing Consortium Using Pulp and Paper Mill Waste Streams

    NASA Astrophysics Data System (ADS)

    Mockos, Gregory R.; Smith, William A.; Loge, Frank J.; Thompson, David N.

    Efficient utilization of carbon inputs is critical to the economic viability of the current forest products sector. Input carbon losses occur in various locations within a pulp mill, including losses as volatile organics and wastewater. Opportunities exist to capture this carbon in the form of value-added products such as biodegradable polymers. Wasteactivated sludge from a pulp mill wastewater facility was enriched for 80 days for a methanol-utilizing consortium with the goal of using this consortium to produce biopolymers from methanol-rich pulp mill waste streams. Five enrichment conditions were utilized: three high-methanol streams from the kraft mill foul condensate system, one methanol-amended stream from the mill wastewater plant, and one methanol-only enrichment. Enrichment reactors were operated aerobically in sequencing batch mode at neutral pH and 25°C with a hydraulic residence time and a solids retention time of 4 days. Non-enriched waste activated sludge did not consume methanol or reduce chemical oxygen demand. With enrichment, however, the chemical oxygen demand reduction over 24-h feed/ decant cycles ranged from 79 to 89%, and methanol concentrations dropped below method detection limits. Neither the non-enriched waste-activated sludge nor any of the enrichment cultures accumulated polyhydroxyalkanoates (PHAs) under conditions of nitrogen sufficiency. Similarly, the non-enriched waste activated sludge did not accumulate PHAs under nitrogen-limited conditions. By contrast, enriched cultures accumulated PHAs to nearly 14% on a dry weight basis under nitrogen-limited conditions. This indicates that selectively enriched pulp mill waste activated sludge can serve as an inoculum for PHA production from methanol-rich pulp mill effluents.

  8. Selective enrichment of a methanol-utilizing consortium using pulp & paper mill waste streams

    SciTech Connect

    Gregory R. Mockos; William A. Smith; Frank J. Loge; David N. Thompson

    2007-04-01

    Efficient utilization of carbon inputs is critical to the economic viability of the current forest products sector. Input carbon losses occur in various locations within a pulp mill, including losses as volatile organics and wastewater . Opportunities exist to capture this carbon in the form of value-added products such as biodegradable polymers. Waste activated sludge from a pulp mill wastewater facility was enriched for 80 days for a methanol-utilizing consortium with the goal of using this consortium to produce biopolymers from methanol-rich pulp mill waste streams. Five enrichment conditions were utilized: three high-methanol streams from the kraft mill foul condensate system, one methanol-amended stream from the mill wastewater plant, and one methanol-only enrichment. Enrichment reactors were operated aerobically in sequencing batch mode at neutral pH and 25°C with a hydraulic residence time and a solids retention time of four days. Non-enriched waste activated sludge did not consume methanol or reduce chemical oxygen demand. With enrichment, however, the chemical oxygen demand reduction over 24 hour feed/decant cycles ranged from 79 to 89 %, and methanol concentrations dropped below method detection limits. Neither the non-enriched waste activated sludge nor any of the enrichment cultures accumulated polyhydroxyalkanoates (PHAs) under conditions of nitrogen sufficiency. Similarly, the non-enriched waste activated sludge did not accumulate PHAs under nitrogen limited conditions. By contrast, enriched cultures accumulated PHAs to nearly 14% on a dry weight basis under nitrogen limited conditions. This indicates that selectively-enriched pulp mill waste activated sludge can serve as an inoculum for PHA production from methanol-rich pulp mill effluents.

  9. Selective enrichment of a methanol-utilizing consortium using pulp and paper mill waste streams.

    PubMed

    Mockos, Gregory R; Smith, William A; Loge, Frank J; Thompson, David N

    2008-03-01

    Efficient utilization of carbon inputs is critical to the economic viability of the current forest products sector. Input carbon losses occur in various locations within a pulp mill, including losses as volatile organics and wastewater. Opportunities exist to capture this carbon in the form of value-added products such as biodegradable polymers. Waste-activated sludge from a pulp mill wastewater facility was enriched for 80 days for a methanol-utilizing consortium with the goal of using this consortium to produce biopolymers from methanol-rich pulp mill waste streams. Five enrichment conditions were utilized: three high-methanol streams from the kraft mill foul condensate system, one methanol-amended stream from the mill wastewater plant, and one methanol-only enrichment. Enrichment reactors were operated aerobically in sequencing batch mode at neutral pH and 25 degrees C with a hydraulic residence time and a solids retention time of 4 days. Non-enriched waste activated sludge did not consume methanol or reduce chemical oxygen demand. With enrichment, however, the chemical oxygen demand reduction over 24-h feed/decant cycles ranged from 79 to 89%, and methanol concentrations dropped below method detection limits. Neither the non-enriched waste-activated sludge nor any of the enrichment cultures accumulated polyhydroxyalkanoates (PHAs) under conditions of nitrogen sufficiency. Similarly, the non-enriched waste activated sludge did not accumulate PHAs under nitrogen-limited conditions. By contrast, enriched cultures accumulated PHAs to nearly 14% on a dry weight basis under nitrogen-limited conditions. This indicates that selectively enriched pulp mill waste activated sludge can serve as an inoculum for PHA production from methanol-rich pulp mill effluents. PMID:18418753

  10. Chronic nutrient enrichment increases prevalence and severity of coral disease and bleaching.

    PubMed

    Vega Thurber, Rebecca L; Burkepile, Deron E; Fuchs, Corinne; Shantz, Andrew A; McMinds, Ryan; Zaneveld, Jesse R

    2014-02-01

    Nutrient loading is one of the strongest drivers of marine habitat degradation. Yet, the link between nutrients and disease epizootics in marine organisms is often tenuous and supported only by correlative data. Here, we present experimental evidence that chronic nutrient exposure leads to increases in both disease prevalence and severity and coral bleaching in scleractinian corals, the major habitat-forming organisms in tropical reefs. Over 3 years, from June 2009 to June 2012, we continuously exposed areas of a coral reef to elevated levels of nitrogen and phosphorus. At the termination of the enrichment, we surveyed over 1200 scleractinian corals for signs of disease or bleaching. Siderastrea siderea corals within enrichment plots had a twofold increase in both the prevalence and severity of disease compared with corals in unenriched control plots. In addition, elevated nutrient loading increased coral bleaching; Agaricia spp. of corals exposed to nutrients suffered a 3.5-fold increase in bleaching frequency relative to control corals, providing empirical support for a hypothesized link between nutrient loading and bleaching-induced coral declines. However, 1 year later, after nutrient enrichment had been terminated for 10 months, there were no differences in coral disease or coral bleaching prevalence between the previously enriched and control treatments. Given that our experimental enrichments were well within the ranges of ambient nutrient concentrations found on many degraded reefs worldwide, these data provide strong empirical support to the idea that coastal nutrient loading is one of the major factors contributing to the increasing levels of both coral disease and coral bleaching. Yet, these data also suggest that simple improvements to water quality may be an effective way to mitigate some coral disease epizootics and the corresponding loss of coral cover in the future. PMID:24277207

  11. Prefrontal microRNA-221 Mediates Environmental Enrichment-Induced Increase of Locomotor Sensitivity to Nicotine

    PubMed Central

    Gomez, Adrian M.; Altomare, Diego; Sun, Wei-Lun; Midde, Narasimha M.; Ji, Hao; Shtutman, Michael; Turner, Jill R.; Creek, Kim E.

    2016-01-01

    Background: Environmental enrichment alters susceptibility in developing drug addiction. We have demonstrated that rats raised in an enriched condition are more sensitive than rats raised in an impoverished condition to nicotine-induced locomotor activity, and this is associated with alterations of phosphorylated extracellular signal-regulated kinase 1/2 within the prefrontal cortex. This study determined the impact of microRNA-221 in the prefrontal cortex on phosphorylated extracellular signal-regulated kinase 1/2 and the enriched environment-dependent behavioral changes in response to nicotine. Methods: A microRNA array was conducted to profile microRNA expression in the prefrontal cortex of enriched condition and impoverished condition rats in response to repeated nicotine (0.35mg/kg, s.c.) administration. microRNA-221 in the prefrontal cortex, nucleus accumbens, and striatum was further verified by quantitative real-time PCR. Lentiviral-mediated overexpression of microRNA-221 in PC12 cells and the medial prefrontal cortex was performed to determine the effects of microRNA-221 on nicotine-mediated phosphorylated extracellular signal-regulated kinase 1/2, phosphorylated cAMP-response element-binding protein, and locomotor activity. Results: microRNA-221 was profoundly upregulated in the prefrontal cortex but not in nucleus accumbens and striatum of enriched condition rats relative to impoverished condition rats following repeated administration of nicotine. Overexpression of lentiviral-microRNA-221 attenuated nicotine-induced increase in phosphorylated extracellular signal-regulated kinase 1/2 in PC12 cells. Lentiviral-microRNA-221 overexpression in the medial prefrontal cortex further increased locomotor activity in impoverished condition but not in enriched condition rats in response to repeated nicotine administration. Accordingly, lentiviral-microRNA-221 attenuated nicotine-induced increases in phosphorylated extracellular signal-regulated kinase 1/2 and

  12. CO2 enrichment increases carbon and nitrogen input from fine roots in a deciduous forest.

    PubMed

    Iversen, Colleen M; Ledford, Joanne; Norby, Richard J

    2008-01-01

    * Greater fine-root production under elevated [CO2] may increase the input of carbon (C) and nitrogen (N) to the soil profile because fine root populations turn over quickly in forested ecosystems. * Here, the effect of elevated [CO)] was assessed on root biomass and N inputs at several soil depths by combining a long-term minirhizotron dataset with continuous, root-specific measurements of root mass and [N]. The experiment was conducted in a CO(2)-enriched sweetgum (Liquidambar styraciflua) plantation. * CO2) enrichment had no effect on root tissue density or [N] within a given diameter class. Root biomass production and standing crop were doubled under elevated [CO2]. Though fine-root turnover declined under elevated [CO2], fine-root mortality was also nearly doubled under CO2 enrichment. Over 9 yr, root mortality resulted in 681 g m(-2) of extra C and 9 g m(-2) of extra N input to the soil system under elevated [CO2]. At least half of these inputs were below 30 cm soil depth. * Increased C and N input to the soil under CO2 enrichment, especially below 30 cm depth, might alter soil C storage and N mineralization. Future research should focus on quantifying root decomposition dynamics and C and N mineralization deeper in the soil. PMID:18537885

  13. Prospecting for ice association: characterization of freeze-thaw selected enrichment cultures from latitudinally distant soils.

    PubMed

    Wilson, Sandra L; Grogan, Paul; Walker, Virginia K

    2012-04-01

    Freeze-thaw stress has previously been shown to alter soil community structure and function. We sought to further investigate this stress on enriched microbial consortia with the aim of identifying microbes with ice-associating adaptations that facilitate survival. Enrichments were established to obtain culturable psychrotolerant microbes from soil samples from the latitudinal extremes of the Canadian Shield plateau. The resulting consortia were subjected to consecutive freeze-thaw cycles, and survivors were putatively identified by their 16S rRNA gene sequences. Even though the northerly site was exposed to longer, colder winters and large spring-time temperature fluctuations, the selective regime similarly affected both enriched consortia. Quantitative PCR and metagenomic sequencing were used to determine the frequency of a subset of the resistant microbes in the original enrichments. The metagenomes showed 22 initial genera, only 6 survived and these were not dominant prior to selection. When survivors were assayed for ice recrystallization inhibition and ice nucleation activities, over 60% had at least one of these properties. These phenotypes were not more prevalent in the northern enrichment, indicating that regarding these adaptations, the enrichment strategy yielded seemingly functionally similar consortia from each site. PMID:22435705

  14. Using targeted enrichment of nuclear genes to increase phylogenetic resolution in the neotropical rain forest genus Inga (Leguminosae: Mimosoideae)

    PubMed Central

    Nicholls, James A.; Pennington, R. Toby; Koenen, Erik J. M.; Hughes, Colin E.; Hearn, Jack; Bunnefeld, Lynsey; Dexter, Kyle G.; Stone, Graham N.; Kidner, Catherine A.

    2015-01-01

    Evolutionary radiations are prominent and pervasive across many plant lineages in diverse geographical and ecological settings; in neotropical rainforests there is growing evidence suggesting that a significant fraction of species richness is the result of recent radiations. Understanding the evolutionary trajectories and mechanisms underlying these radiations demands much greater phylogenetic resolution than is currently available for these groups. The neotropical tree genus Inga (Leguminosae) is a good example, with ~300 extant species and a crown age of 2–10 MY, yet over 6 kb of plastid and nuclear DNA sequence data gives only poor phylogenetic resolution among species. Here we explore the use of larger-scale nuclear gene data obtained though targeted enrichment to increase phylogenetic resolution within Inga. Transcriptome data from three Inga species were used to select 264 nuclear loci for targeted enrichment and sequencing. Following quality control to remove probable paralogs from these sequence data, the final dataset comprised 259,313 bases from 194 loci for 24 accessions representing 22 Inga species and an outgroup (Zygia). Bayesian phylogenies reconstructed using either all loci concatenated or a gene-tree/species-tree approach yielded highly resolved phylogenies. We used coalescent approaches to show that the same targeted enrichment data also have significant power to discriminate among alternative within-species population histories within the widespread species I. umbellifera. In either application, targeted enrichment simplifies the informatics challenge of identifying orthologous loci associated with de novo genome sequencing. We conclude that targeted enrichment provides the large volumes of phylogenetically-informative sequence data required to resolve relationships within recent plant species radiations, both at the species level and for within-species phylogeographic studies. PMID:26442024

  15. Hydrophilic modification of titania nanomaterials as a biofunctional adsorbent for selective enrichment of phosphopeptides.

    PubMed

    Liu, Hailong; Yang, Tianyi; Dai, Junyong; Zhu, Jiayu; Li, Xiaoran; Wen, Rui; Yang, Xinghao

    2015-10-01

    TiO2-based metal oxide affinity chromatography (MOAC) nanomaterials show high potential in phosphoproteome mass-spectrometric (MS) analysis. However, a drawback of TiO2 nanomaterials is poor water solubility, which greatly reduces the enrichment efficiency of phosphopeptides and eventually limits their use in phosphoproteome MS analysis. In this work, a hydrophilic TiO2 hybrid material (denoted as NH2@TiO2) is successfully designed with 1,6-hexanediamine modified on the surface of TiO2 nanoparticles and applied as a biofunctional adsorbent for selective enrichment of phosphopeptides. The novel TiO2 hybrid material with high hydrophilicity and biocompatibility is characterized using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and infrared (IR) spectroscopy, and its performance in selective enrichment of phosphopeptides is evaluated with the standard protein digests, human serum and the tryptic digests of nonfat milk. PMID:26299437

  16. A new selective enrichment procedure for isolating Pasteurella multocida from avian and environmental samples

    USGS Publications Warehouse

    Moore, M.K.; Cicnjak-Chubbs, L.; Gates, R.J.

    1994-01-01

    A selective enrichment procedure, using two new selective media, was developed to isolate Pasteurella multocida from wild birds and environmental samples. These media were developed by testing 15 selective agents with six isolates of P. multocida from wild avian origin and seven other bacteria representing genera frequently found in environmental and avian samples. The resulting media—Pasteurella multocida selective enrichment broth and Pasteurella multocida selective agar—consisted of a blood agar medium at pH 10 containing gentamicin, potassium tellurite, and amphotericin B. Media were tested to determine: 1) selectivity when attempting isolation from pond water and avian carcasses, 2) sensitivity for detection of low numbers of P. multocida from pure and mixed cultures, 3) host range specificity of the media, and 4) performance compared with standard blood agar. With the new selective enrichment procedure, P. multocida was isolated from inoculated (60 organisms/ml) pond water 84% of the time, whereas when standard blood agar was used, the recovery rate was 0%.

  17. Effect of carbon enrichment induced by photoresist on highly selective SiO2 etching

    NASA Astrophysics Data System (ADS)

    Chu, Changwoong; Chi, Kyeong-Koo; Moon, Joo-Tae

    2002-11-01

    We propose two models to discuss the behavior of the selective etching of SiO2 to the underlying Si3N4 with changing wafer surface temperatures. For this investigation, three specimens, SiO2, Si3N4, and poly-Si, which are nonpatterned, photoresist-patterned, and poly-silicon-patterned, respectively, have been etched in a surface wave plasma system equipped with an electrostatic chuck for wafer temperature control. The coolant temperature, which controls the wafer temperature, has been changed from -20 to 50 °C. For the nonpatterned wafer, the etch rates of SiO2, Si3N4, and poly-Si increase and the selectivities decreases with wafer temperature. However, for the samples patterned with either photoresist or poly-Si, the etch rates of SiO2 decrease with wafer temperature. The temperature rise also leads to an enhancement of selectivity of SiO2/Si3N4, and the steeper profile angles. The presence of a masking layer, even for the poly-Si-patterned samples, results in a different etching behavior. This is because the sticking probability of the polymer precursor becomes smaller on the sidewall of the profile with the temperature increase. Therefore the thickness of polymer on the sidewall of the contact hole decreases, and the thickness of polymer on the bottom increases as the wafer temperature goes up. Comparing photoresist-patterned samples with poly-Si-patterned ones, we can corroborate the role of the photoresist mask layer, which provides a higher carbon-to-fluorine ratio at the near surface. The carbon enrichment accelerates more steeply the etch rate decrement of the substrate layer. In summary, there are two main contributions attributed by the substrate temperature: changing the sticking coefficient of the fluorocarbon precursor and enhancing the photoresist erosion.

  18. Polydopamine-coated eppendorf tubes for Ti⁴⁺ immobilization for selective enrichment of phosphopeptides.

    PubMed

    Shi, Chenyi; Deng, Chunhui; Zou, ShiEn; Zhang, Xiangmin

    2014-09-01

    Mass spectrometric technique has emerged as a preferred technique in the analysis of protein phosphorylation. Owing to the low stoichiometry of phosphopeptides and the signal suppression effect by non-phosphopeptides, there is a demand for efficient enrichment of phosphopeptides. The selective enrichment of phosphopeptides in modified eppendorf tubes prior to mass spectrometry analysis, which can minimize sample loss as well as nonspecific interferences effectively, has become a hot topic in current proteomics field. In our work, an easy-to-use phosphopeptide-selective eppendorf tube was initially prepared, with its inner surface being modified with a Ti(4+)-immobilized polydopamine (PDA) layer. The unique Ti(4+)-immobilized PDA-modified eppendorf tubes (EP tube@PDA-Ti(4+)) are investigated for its application in selective enrichment of phosphopeptides from complex biological samples. Due to the high Ti(4+) loading amount on the surface of PDA, the EP tube@PDA-Ti(4+) exhibits remarkable phosphopeptide enrichment ability in protein digests and human serum, which presents a powerful evidence for its high selectivity in detecting the low-abundance phosphopeptides from complex biological samples. PMID:24913861

  19. Larval quality of aquacultured Florida pompano, Trachinotus carolinus L. fed rotifers enriched with selected commercial diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Development of larviculture methods for marine finfish has been a major bottleneck to ensure a consistent and reliable source of seed stock. This study examined the effect of selected rotifer enrichment diets on growth, survival, and fatty acid content of larval Florida pompano, Trachinotus carolin...

  20. Larval performance of aquacultured Florida pompano, Trachinotus carolinus L. fed rotifers enriched with selected commercial diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Development of larviculture methods for marine finfish has been a major bottleneck to ensure a consistent and reliable source of seed stock. This study examined the effect of selected rotifer enrichment diets on growth, survival, and fatty acid content of larval Florida pompano, Trachinotus carolin...

  1. BDNF increases with behavioral enrichment and an antioxidant diet in the aged dog.

    PubMed

    Fahnestock, Margaret; Marchese, Monica; Head, Elizabeth; Pop, Viorela; Michalski, Bernadeta; Milgram, William N; Cotman, Carl W

    2012-03-01

    The aged canine (dog) is an excellent model for investigating the neurobiological changes that underlie cognitive impairment and neurodegeneration in humans, as canines and humans undergo similar pathological and behavioral changes with aging. Recent evidence indicates that a combination of environmental enrichment and antioxidant-fortified diet can be used to reduce the rate of age-dependent neuropathology and cognitive decline in aged dogs, although the mechanisms underlying these changes have not been established. We examined the hypothesis that an increase in levels of brain-derived neurotrophic factor (BDNF) is one of the factors underlying improvements in learning and memory. Old, cognitively impaired animals that did not receive any treatment showed a significant decrease in BDNF mRNA in the temporal cortex when compared with the young group. Animals receiving either an antioxidant diet or environmental enrichment displayed intermediate levels of BDNF mRNA. However, dogs receiving both an antioxidant diet and environmental enrichment showed increased levels of BDNF mRNA when compared with untreated aged dogs, approaching levels measured in young animals. BDNF receptor TrkB mRNA levels did not differ between groups. BDNF mRNA levels were positively correlated with improved cognitive performance and inversely correlated with cortical Aβ((1-42)) and Aβ((1-40)) levels. These findings suggest that environmental enrichment and antioxidant diet interact to maintain brain levels of BDNF, which may lead to improved cognitive performance. This is the first demonstration in a higher animal that nonpharmacological changes in lifestyle in advanced age can upregulate BDNF to levels approaching those in the young brain. PMID:20447733

  2. Special Enrichment Strategies Greatly Increase the Efficiency of Missing Proteins Identification from Regular Proteome Samples.

    PubMed

    Su, Na; Zhang, Chengpu; Zhang, Yao; Wang, Zhiqiang; Fan, Fengxu; Zhao, Mingzhi; Wu, Feilin; Gao, Yuan; Li, Yanchang; Chen, Lingsheng; Tian, Miaomiao; Zhang, Tao; Wen, Bo; Sensang, Na; Xiong, Zhi; Wu, Songfeng; Liu, Siqi; Yang, Pengyuan; Zhen, Bei; Zhu, Yunping; He, Fuchu; Xu, Ping

    2015-09-01

    As part of the Chromosome-Centric Human Proteome Project (C-HPP) mission, laboratories all over the world have tried to map the entire missing proteins (MPs) since 2012. On the basis of the first and second Chinese Chromosome Proteome Database (CCPD 1.0 and 2.0) studies, we developed systematic enrichment strategies to identify MPs that fell into four classes: (1) low molecular weight (LMW) proteins, (2) membrane proteins, (3) proteins that contained various post-translational modifications (PTMs), and (4) nucleic acid-associated proteins. Of 8845 proteins identified in 7 data sets, 79 proteins were classified as MPs. Among data sets derived from different enrichment strategies, data sets for LMW and PTM yielded the most novel MPs. In addition, we found that some MPs were identified in multiple-data sets, which implied that tandem enrichments methods might improve the ability to identify MPs. Moreover, low expression at the transcription level was the major cause of the "missing" of these MPs; however, MPs with higher expression level also evaded identification, most likely due to other characteristics such as LMW, high hydrophobicity and PTM. By combining a stringent manual check of the MS2 spectra with peptides synthesis verification, we confirmed 30 MPs (neXtProt PE2 ∼ PE4) and 6 potential MPs (neXtProt PE5) with authentic MS evidence. By integrating our large-scale data sets of CCPD 2.0, the number of identified proteins has increased considerably beyond simulation saturation. Here, we show that special enrichment strategies can break through the data saturation bottleneck, which could increase the efficiency of MP identification in future C-HPP studies. All 7 data sets have been uploaded to ProteomeXchange with the identifier PXD002255. PMID:26144840

  3. [Selective enrichment of iridoid glucosides in Hedyotis diffusa Willd. by tandem solid phase extraction].

    PubMed

    Zhang, Feng; Guo, Zhimou; Zhang, Feifang; Xue, Xingya; Liang, Xinmiao

    2009-07-01

    A method for selective enrichment of iridoid glucosides in Hedyotis diffusa Willd. by tandem solid phase extraction (SPE) was developed. Oligo(ethylene glycol) (OEG) is a novel type of separation material made in this laboratory. The differences of the surface chemical structures between OEG material and ODS material resulted in their different retention capabilities for iridoid glucosides. Based on the differences, an OEG-ODS solid phase extraction method was designed for selective enrichment of iridoid glucosides. The water extract (150.28 mg) of Hedyotis diffusa Willd. was precipitated by ethanol, and an aliquot (27.03 mg) of the product from the supernatant solution was loaded onto an OEG cartridge and rinsed by 5 mL water. Then, the rinsing solution was loaded onto an ODS cartridge. After it was washed by 5 mL water and eluted by 5 mL methanol, 4.01 mg final product was obtained from the methanol eluent. All the products were characterized by ultra performance liquid chromatography (UPLC), and 14 representative peaks of iridoid glucosides were found. The enrichment results were proved effective by directly comparing the chromatograms each step. To further characterize the enrichment efficiency, the changes of the peak area of iridoid glucosides were investigated. The results showed that the content of 14 iridoid glucosides in the final product reached 6.10 times its original proportion in water extraction product and their recovery was 50.1% on average. Therefore, the iridoid glucosides can be enriched by the tandem solid phase extraction method from water extracting-ethanol precipitating solution of Hedyotis diffusa Willd. with a good selectivity and an acceptable recovery. The proposed method has the advantages of high enrichment efficiency and simple operation. PMID:19938499

  4. Deuterium enrichment by selective photo-induced dissociation of an organic carbonyl compound

    DOEpatents

    Marling, John B.

    1981-01-01

    A method for producing a deuterium enriched material by photoinduced dissociation which uses as the working material a gas phase photolytically dissociable organic carbonyl compound containing at least one hydrogen atom bonded to an atom which is adjacent to a carbonyl group and consisting of molecules wherein said hydrogen atom is present as deuterium and molecules wherein said hydrogen atom is present as another isotope of hydrogen. The organic carbonyl compound is subjected to intense infrared radiation at a preselected wavelength to selectively excite and thereby induce dissociation of the deuterium containing species to yield a deuterium enriched stable molecular product. Undissociated carbonyl compound, depleted in deuterium, is preferably redeuterated for reuse.

  5. Prolonged Drug Selection of Breast Cancer Cells and Enrichment of Cancer Stem Cell Characteristics

    PubMed Central

    Calcagno, Anna Maria; Salcido, Crystal D.; Gillet, Jean-Pierre; Wu, Chung-Pu; Fostel, Jennifer M.; Mumau, Melanie D.; Gottesman, Michael M.; Varticovski, Lyuba

    2010-01-01

    .55 cells per field, P < .001). No enrichment in the CD44+/CD24− or CD133+ population was detected in MCF-7/MDR. Conclusion The cell population with cancer stem cell characteristics increased after prolonged continuous selection for doxorubicin resistance. PMID:20935265

  6. Quercetin Increases Hepatic Homocysteine Remethylation and Transsulfuration in Rats Fed a Methionine-Enriched Diet

    PubMed Central

    Meng, Bin; Gao, Weina; Wei, Jingyu; Pu, Lingling; Tang, Zhenchuang; Guo, Changjiang

    2015-01-01

    This study was aimed at investigating the effects of quercetin on mRNA expression and activity of critical enzymes in homocysteine metabolism in rats fed a methionine-enriched diet. Rats were fed for 6 weeks the following diets, that is, control, 0.5% quercetin, 1.0% methionine, and 1.0% methionine plus 0.5% quercetin diets. Serum homocysteine was significantly increased after methionine treatment and decreased after the addition of quercetin. The mRNA expression of methionine synthase was significantly increased after methionine or methionine plus quercetin supplementation, while its enzymatic activity was significantly increased after methionine plus quercetin supplementation. The mRNA expression and enzymatic activity of cystathionine β-synthase and cystathionine γ-lyase were upregulated after quercetin, methionine, or quercetin plus methionine treatment and a more significant increase was observed for hepatic cystathionine β-synthase in the methionine plus quercetin treated rats, suggesting an interaction between methionine and quercetin. Meanwhile, hepatic ratio of S-adenosylmethionine to S-adenosylhomocysteine was significantly decreased in response to methionine supplementation and normalized after the addition of quercetin. It is concluded that quercetin reduces serum homocysteine by increasing remethylation and transsulfuration of homocysteine in rats exposed to a methionine-enriched diet. PMID:26558284

  7. Amine-functionalized TiO₂ nanoparticles for highly selective enrichment of phosphopeptides.

    PubMed

    Liu, Hailong; Zhou, Jiahong; Huang, Heyong

    2015-10-01

    Specific enrichment of trace phosphoproteins or phosphopeptides from complex biological samples prior to mass spectrometry analysis is of profound significance for in-depth phosphoproteomics. In this work, an amine-functionalized TiO2 nano-material with N'[3-(trimethoxysilyl)-propyl] diethylenetriamine (TPDA) modified on the surface of nanoparticle TiO2 (TiO2@TPDA) was successfully designed and applied for the enrichment of phosphopeptides. Compared with pure TiO2, the novel prepared TiO2@TPDA possessed lower Lewis acidity, enhanced hydrophilicity and stronger affinity to phosphopeptides, and its performance for selective and effective enrichment of phosphopeptide was investigated by the standard protein digests and human serum. PMID:26078180

  8. Nutrient enrichment can increase the susceptibility of reef corals to bleaching

    NASA Astrophysics Data System (ADS)

    Wiedenmann, Jörg; D'Angelo, Cecilia; Smith, Edward G.; Hunt, Alan N.; Legiret, François-Eric; Postle, Anthony D.; Achterberg, Eric P.

    2013-02-01

    Mass coral bleaching, resulting from the breakdown of coral-algal symbiosis has been identified as the most severe threat to coral reef survival on a global scale. Regionally, nutrient enrichment of reef waters is often associated with a significant loss of coral cover and diversity. Recently, increased dissolved inorganic nitrogen concentrations have been linked to a reduction of the temperature threshold of coral bleaching, a phenomenon for which no mechanistic explanation is available. Here we show that increased levels of dissolved inorganic nitrogen in combination with limited phosphate concentrations result in an increased susceptibility of corals to temperature- and light-induced bleaching. Mass spectrometric analyses of the algal lipidome revealed a marked accumulation of sulpholipids under these conditions. Together with increased phosphatase activities, this change indicates that the imbalanced supply of dissolved inorganic nitrogen results in phosphate starvation of the symbiotic algae. Based on these findings we introduce a conceptual model that links unfavourable ratios of dissolved inorganic nutrients in the water column with established mechanisms of coral bleaching. Notably, this model improves the understanding of the detrimental effects of coastal nutrient enrichment on coral reefs, which is urgently required to support knowledge-based management strategies to mitigate the effects of climate change.

  9. PHOS-Select Iron Affinity beads enrich peptides for detection of organophosphorus adducts on albumin

    PubMed Central

    Jiang, Wei; Dubrovskii, Yaroslav A; Podolskaya, Ekaterina P; Murashko, Ekaterina A; Babakov, Vladimir; Nachon, Florian; Masson, Patrick; Schopfer, Lawrence M; Lockridge, Oksana

    2013-01-01

    Albumin is covalently modified by organophosphorus toxicants (OP) on tyrosine 411, but less than 1% of albumin is modified in humans by lethal OP doses that inhibit 95% of plasma butyrylcholinesterase. A method that enriches OP-modified albumin peptides could aid analysis of low dose exposures. Soman or chlorpyrifos oxon treated human plasma was digested with pepsin. Albumin peptides were enriched by binding to Fe3+ beads at pH 11 and eluted with pH 2.6 buffer. Similarly, mouse and guinea pig albumin modified by chlorpyrifos oxon were digested with pepsin and enriched by binding to Fe3+ beads. Peptides were identified by MALDI-TOF/TOF mass spectrometry. PHOS-select Iron Affinity beads specifically enriched albumin peptides VRY411TKKVPQVST and LVRY411TKKVPQVST in a pepsin digest of human plasma. The unmodified as well as OP-modified peptides bound to the beads. The binding capacity of 500 μl beads was the pepsin digest of 2.1 μL human plasma. The limit of detection was 0.2% of OP-modified albumin peptide in 0.43 μL plasma. Enrichment of OP-modified albumin peptides by binding to Fe3+ beads is a method with potential application to diagnosis of OP pesticide and nerve agent exposure in humans, mice, and guinea pigs. PMID:24187955

  10. PHOS-select iron affinity beads enrich peptides for the detection of organophosphorus adducts on albumin.

    PubMed

    Jiang, Wei; Dubrovskii, Yaroslav A; Podolskaya, Ekaterina P; Murashko, Ekaterina A; Babakov, Vladimir; Nachon, Florian; Masson, Patrick; Schopfer, Lawrence M; Lockridge, Oksana

    2013-12-16

    Albumin is covalently modified by organophosphorus toxicants (OP) on tyrosine 411, but less than 1% of albumin is modified in humans by lethal OP doses that inhibit 95% of plasma butyrylcholinesterase. A method that enriches OP-modified albumin peptides could aid analysis of low dose exposures. Soman or chlorpyrifos oxon treated human plasma was digested with pepsin. Albumin peptides were enriched by binding to Fe(3+) beads at pH 11 and eluted with pH 2.6 buffer. Similarly, mouse and guinea pig albumin modified by chlorpyrifos oxon were digested with pepsin and enriched by binding to Fe(3+) beads. Peptides were identified by MALDI-TOF/TOF mass spectrometry. PHOS-select iron affinity beads specifically enriched albumin peptides VRY411TKKVPQVST and LVRY411TKKVPQVST in a pepsin digest of human plasma. The unmodified as well as OP-modified peptides bound to the beads. The binding capacity of 500 μL of beads was the pepsin digest of 2.1 μL of human plasma. The limit of detection was 0.2% of OP-modified albumin peptide in 0.43 μL of plasma. Enrichment of OP-modified albumin peptides by binding to Fe(3+) beads is a method with potential application to diagnosis of OP pesticide and nerve agent exposure in humans, mice, and guinea pigs. PMID:24187955

  11. Increase in Alphaproteobacteria in association with a polychaete, Capitella sp. I, in the organically enriched sediment

    PubMed Central

    Kunihiro, Tadao; Takasu, Hiroyuki; Miyazaki, Tomoaki; Uramoto, Yuuta; Kinoshita, Kyoko; Yodnarasri, Supaporn; Hama, Daigo; Wada, Minoru; Kogure, Kazuhiro; Ohwada, Kouichi; Tsutsumi, Hiroaki

    2011-01-01

    We conducted bioremediation experiments on the organically enriched sediment on the sea floor just below a fish farm, introducing artificially mass-cultured colonies of deposit-feeding polychaete, Capitella sp. I. To clarify the association between the Capitella and bacteria on the efficient decomposition of the organic matter in the sediment in the experiments, we tried to identify the bacteria that increased in the microbial community in the sediment with dense patches of the Capitella. The relationship between TOC and quinone content of the sediment as an indicator of the bacterial abundance was not clear, while a significant positive correlation was found between Capitella biomass and quinone content of the sediment. In particular, ubiquinone-10, which is present in members of the class Alphaproteobacteria, increased in the sediment with dense patches of the Capitella. We performed denaturing gradient gel electrophoresis (DGGE) analyses to identify the alphaproteobacterial species in the sediment with dense patches of the worm, using two DGGE fragments obtained from the sediment samples and one fragment from the worm body. The sequences of these DGGE fragments were closely related to the specific members of the Roseobacter clade. In the associated system with the Capitella and the bacteria in the organically enriched sediment, the decomposition of the organic matter may proceed rapidly. It is very likely that the Capitella works as a promoter of bacteria in the organically enriched sediment, and feeds the increased bacteria as one of the main foods, while the bacteria decompose the organic matter in the sediment with the assistance of the Capitella. PMID:21544104

  12. Preparation of Concanavalin A-Chelating Magnetic Nanoparticles for Selective Enrichment of Glycoproteins.

    PubMed

    Dong, Liping; Feng, Shun; Li, Shanshan; Song, Peipei; Wang, Jide

    2015-07-01

    In this work, a soft and nondestructive approach was developed to prepare concanavalin A-chelating magnetic nanoparticles (Con A-MNPs) for selective enrichment of glycoproteins. Ethylenediamine tetraacetic acid-modified-MNPs (EDTA-MNPs) were prepared by a one-pot chemical coprecipitation method first, and then, Cu(II) cations were used as bridge groups to immobilize Con A on EDTA-MNPs. The as-prepared absorbents with a mean diameter of 15 nm showed a strong magnetic response to an externally applied magnetic field. The results of thermogravimetric analysis showed the content of immobilized Con A was up to 28 wt %. For glycoprotein ovalbumin, the maximum capacity and equilibrium constant were 72.41 mg/g and 0.6035 L/mg, respectively. The as-prepared nanocomposites exhibited a remarkable selectivity for glycoproteins and can enrich glycoproteins specifically from a mixture of glycoprotein and nonglycoprotein even at a molar ratio of 1:600. It was also successfully applied for the enrichment of glycoproteins from real egg white samples. We expect that our finding will serve as a helpful template for others to design new adsorbents for enriching glycoproteins. PMID:26066908

  13. Enhanced accumulation of PCB congeners by Baltic Sea blue mussels, Mytilus edulis, with increased algae enrichment

    SciTech Connect

    Gilek, M.; Bjoerk, M.; Broman, D.; Kautsky, N.; Naef, C.

    1996-09-01

    The objective of this study was to examine if natural variations in the quantity of phytoplankton-derived particulate and dissolved organic carbon influences the accumulation of polychlorinated biphenyls (PCBs) in the tissues of Baltic Sea blue mussels (Mytilus edulis L.). In a laboratory flow-through experiment the authors exposed M. edulis to the technical PCB mixture Aroclor{reg_sign} 1248 for 21 d at three different enrichments of the unicellular green algae Chlamydomonas sp., 0.10, 0.16, and 0.32 mg particulate organic carbon (POC)/L. Tissue and water concentrations were determined for seven PCB congeners and 21-d bioaccumulation factors were calculated against total water concentrations. Contrary to what would be expected, an increase in algae enrichment from 0.10 to 0.32 mg POC/L resulted in an enhanced PCB accumulation by a factor of approx. 2. This increase in PCB accumulation was more pronounced for PCB congeners with lower hydrophobicity. These observations have implications for the design of laboratory accumulation studies and potentially for PCB accumulation and cycling in field populations of suspension-feeding mussels in response to changes in eutrophication status.

  14. An integrated microfluidic platform for negative selection and enrichment of cancer cells

    NASA Astrophysics Data System (ADS)

    Luo, Wen-Yi; Tsai, Sung-Chi; Hsieh, Kuangwen; Lee, Gwo-Bin

    2015-08-01

    Circulating tumor cells (CTCs), tumor cells that disseminate from primary tumors to the bloodstream, have recently emerged as promising indicators for cancer diagnosis and prognosis. However, the technical difficulties in isolating and detecting rare CTCs have limited the widespread applicability of this method to date. In this work, a new integrated microfluidic system integrating micromixers and micropumps capable of performing ‘negative selection and enrichment’ of CTCs was developed. By using anti-human CD45 antibodies-coated magnetic beads, leukocytes were effectively removed by applying an external magnetic force, leaving behind an enriched target cell population. The on-chip CTC recovery rate was experimentally found to be 70   ±   5% after a single round of negative selection and enrichment. Meanwhile, CD45 depletion efficiency was 83.99   ±   1.00% and could be improved to 99.84   ±   0.04% after three consecutive rounds of depletion. Notably, on-chip negative selection and enrichment was 58% faster and the repeated depletion could be processed automatically. These promising results suggested the developed microfluidic chip is potentiated for a standardized CTC isolation platform. Preliminary results of the current paper were presented at Micro TAS 2014, San Antonio, Texas, USA, October 26-30, 2014.

  15. Selective enrichment of phenols from coal liquefaction oil by solid phase extraction method

    SciTech Connect

    Tian, M.; Feng, J.

    2009-07-01

    This study focuses on the solid phase extraction method for the enrichment and separation of phenol from coal liquefaction oil. The phenols' separation efficiency was compared on different solid phase extraction (SPE) cartridges, and the effect of solvents with different polarity and solubility parameter on amino-bonded silica was compared for selection of optimal elution solution. The result showed that amino-bonded silica has the highest selectivity and best extraction capability due to two factors, weak anion exchange adsorption and polar attraction adsorption.

  16. Selective weathering of shocked minerals and chondritic enrichment of the Martian fines

    NASA Technical Reports Server (NTRS)

    Boslough, M. B.

    1987-01-01

    In a recent paper, Boslough and Cygan reported the observation of shock-enhanced chemical weathering kinetics of three silicate minerals. Based on the experimental data and on those of Tyburczy and Ahrens for enhanced dehydration kinetics of shocked serpentine, a mechnaism is proposed by which shock-activated minerals are selectively weathered on the surface of Mars. The purpose of the present abstract is to argue on the basis of relative volumes of shocked materials that, as a direct consequence of selective weathering, the composition of the weathered surface units on Mars should be enriched in meteoritic material.

  17. Top-down Feedback Exacerbates Effects of Nutrient Enrichment in Detritus-based Ecosystems via Increased Loss of Basal Carbon

    NASA Astrophysics Data System (ADS)

    Rosemond, A. D.; Suberkropp, K.; Cross, W. F.; Greenwood, J. L.; Eggert, S. L.; Taylor, N.; Wallace, J.

    2005-05-01

    In primary producer-based food webs faced with chronic nutrient enrichment, increased plant biomass may ultimately be suppressed by consumers. Effects of chronic enrichment of detritus-based ecosystems may be fundamentally different, with consumers exacerbating, rather than suppressing, the effects of enrichment on basal resources. We have continuously enriched a headwater stream at the Coweeta LongTerm Ecological Research site (North Carolina, USA) with N & P (to ca. 400 ug/L dissolved inorganic nitrogen and 50 ug/L soluble reactive phosphorus) for 4.5 yrs and quantified leaf breakdown rates, microbial production, invertebrate production, and leaf litter standing crop in the enriched stream and in an adjacent reference stream. Whereas nutrient enrichment largely increases basal carbon in primary producer-based systems, detrital carbon in the treatment stream was drastically diminished relative to the reference stream. During each successive year of enrichment, rates of leaf breakdown were progressively faster and standing crops of detrital carbon were progressively lower. This `ramping up' of loss rates of carbon appear to be driven by increased consumption by invertebrates, rather than increased microbial activity. Our results illustrate that fundamentally different trophic feedback effects can potentially occur in detrital vs primary producer components of food webs in response to increased nutrient concentrations.

  18. Increased antioxidant content in juice enriched with dried extract of pomegranate (Punica granatum) peel.

    PubMed

    Mastrodi Salgado, Jocelem; Baroni Ferreira, Tânia Rachel; de Oliveira Biazotto, Fúvia; Dos Santos Dias, Carlos Tadeu

    2012-03-01

    Antioxidants are compounds responsible for free radical scavenging in the body. They protect the organism from oxidative modification of cells and tissues. These modifications have been associated with degenerative diseases, atherosclerosis and carcinogenesis. Punica granatum displays high antioxidant potential due to the presence of phenolic compounds, which are capable of disease prevention. The present study showed the highest antioxidant activity in pomegranate peel than in seeds and pulp. Based on these results, pomegranate peel was used to produce dried extract that was added to commercial tomato juice and orange juice with strawberries. Analysis to determine the content of phenolic compounds and antioxidant activity was performed on pomegranate pulp, seeds and peel and in juices enriched with dried extract of pomegranate peel. The dried extract was responsible for a significant increase in antioxidant activity of the juices, proportional to the concentrations added. However, although both flavors of enriched juices displayed high antioxidant levels, the samples with higher dried extract concentrations received the lowest scores from sensory analysis participants due to the characteristic astringent flavor of pomegranate peels. Therefore, to obtain greater acceptance in the consumer market, we concluded that the maximum addition of dried pomegranate peel extract is 0.5% in tomato juice and orange juice with strawberries. PMID:22392496

  19. Is more choice always desirable? Evidence and arguments from leks, food selection, and environmental enrichment.

    PubMed

    Hutchinson, John M C

    2005-02-01

    Recent studies on humans show that too much choice can make subjects less likely to choose any item. I consider general adaptive and non-adaptive explanations of why such choice aversion, or its converse, might occur in animals. There are three questions: is more choice always preferred, does it ever lead to less consumption (or a lower probability of consumption), and may it result in worse items being selected ? A preference for choice is one of the main explanations for lek formation and I draw attention to previously unrecognised parallels with models of human shopping behaviour. There is indeed evidence of female preference for larger leks, although much of the observational data are open to other interpretations. Unfortunately nobody has looked for choice aversion where it is most to be expected, in leks larger than normally occur. Evidence that too much choice of males confuses females is strongest in acoustically advertising frogs, but the widespread decrease of mating skew in larger leks might also have this explanation. A model reanalyses data on skew in black grouse Tetrao tetrix and suggests that considering only a random subset of a large lek may increase the chances of selecting the better males: larger leks are more likely to include better males, but these are less likely to be selected. These opposing effects may lead to an optimum lek size, but only with a sufficient decline in choice accuracy with size. With food choice, very few studies have avoided confounding choice with food quality, by manipulating only flavour. The widespread phenomena of stimulus-specific satiety and novelty seeking imply that monotonous diets are aversive, but no studies test whether animals choose sites where they know food diversity to be greater. Operant experiments that demonstrate mild preferences for free choice concern choice about the means to get food rather than the food itself. In some insect species even moderate choice of diet can be deleterious, and studies

  20. Selective Enrichment Media Bias the Types of Salmonella enterica Strains Isolated from Mixed Strain Cultures and Complex Enrichment Broths

    PubMed Central

    Gorski, Lisa

    2012-01-01

    For foodborne outbreak investigations it can be difficult to isolate the relevant strain from food and/or environmental sources. If the sample is contaminated by more than one strain of the pathogen the relevant strain might be missed. In this study mixed cultures of Salmonella enterica were grown in one set of standard enrichment media to see if culture bias patterns emerged. Nineteen strains representing four serogroups and ten serotypes were compared in four-strain mixtures in Salmonella-only and in cattle fecal culture enrichment backgrounds using Salmonella enrichment media. One or more strain(s) emerged as dominant in each mixture. No serotype was most fit, but strains of serogroups C2 and E were more likely to dominate enrichment culture mixtures than strains of serogroups B or C1. Different versions of Rappaport-Vassiliadis (RV) medium gave different patterns of strain dominance in both Salmonella-only and fecal enrichment culture backgrounds. The fittest strains belonged to serogroups C1, C2, and E, and included strains of S. Infantis, S. Thompson S. Newport, S. 6,8:d:-, and S. Give. Strains of serogroup B, which included serotypes often seen in outbreaks such as S. Typhimurium, S. Saintpaul, and S. Schwarzengrund were less likely to emerge as dominant strains in the mixtures when using standard RV as part of the enrichment. Using a more nutrient-rich version of RV as part of the protocol led to a different pattern of strains emerging, however some were still present in very low numbers in the resulting population. These results indicate that outbreak investigations of food and/or other environmental samples should include multiple enrichment protocols to ensure isolation of target strains of Salmonella. PMID:22496847

  1. L-Lactate-selective microbial sensor based on flavocytochrome b2-enriched yeast cells using recombinant and nanotechnology approaches.

    PubMed

    Karkovska, Maria; Smutok, Oleh; Stasyuk, Nataliya; Gonchar, Mykhailo

    2015-11-01

    In the recent years, nanotechnology is the most developing branch due to a wide variety of potential applications in biomedical, biotechnological and agriculture fields. The binding nanoparticles with various biological molecules makes them attractive candidates for using in sensor technologies. The particularly actual is obtaining the bionanomembranes based on biocatalytic elements with improved sensing characteristics. The aim of this investigation is to study the properties of microbial L-lactate-selective sensor based on using the recombinant Hansenula polymorpha yeast cells overproducing flavocytochrome b2 (FC b2), as well as additionally enriched by the enzyme bound with gold nanoparticles (FC b2-nAu). Although, the high permeability of the living cells to nanoparticles is being intensively studied (mostly for delivery of drugs), the idea of using both recombinant technology and nanotechnology to increase the amount of the target enzyme in the biosensing layer is really novel. The FC b2-nAu-enriched living and permeabilized yeast cells were used for construction of a bioselective membrane of microbial L-lactate-selective amperometric biosensor. Phenazine methosulphate was served as a free defusing electron transfer mediator which provides effective electron transfer from the reduced enzyme to the electrode surface. It was shown that the output to L-lactate of FC b2-nAu-enriched permeabilized yeast cells is 2.5-fold higher when compared to the control cells. The obtained results confirm that additional enrichment of the recombinant yeast cell by the enzyme bound with nanoparticles improves the analytical parameters of microbial sensor. PMID:26452947

  2. Selective enrichment in bioactive compound from Kniphofia uvaria by super/subcritical fluid extraction and centrifugal partition chromatography.

    PubMed

    Duval, Johanna; Destandau, Emilie; Pecher, Virginie; Poujol, Marion; Tranchant, Jean-François; Lesellier, Eric

    2016-05-20

    Nowadays, a large portion of synthetic products (active cosmetic and therapeutic ingredients) have their origin in natural products. Kniphofia uvaria is a plant from Africa which has proved in the past by in-vivo tests an antioxidant activity due to compounds present in roots. Recently, we have observed anthraquinones in K. uvaria seeds extracts. These derivatives are natural colorants which could have interesting bioactive potential. The aim of this study was to obtain an extract enriched in anthraquinones from K. uvaria seeds which mainly contains glycerides. First, the separation of the seed compounds was studied by using supercritical fluid chromatography (SFC) in the goal to provide a rapid quantification method of these bioactive compounds. A screening of numerous polar stationary phases was achieved for selecting the most suited phase to the separation of the four anthraquinones founded in the seeds. A gradient elution was optimized for improving the separation of the bioactive compounds from the numerous other families of major compounds of the extracts (fatty acids, di- and triglycerides). Besides, a non-selective and green Supercritical Fluid Extraction (SFE) with pure CO2 was applied to seeds followed by a Centrifugal Partition Chromatography (CPC). The CPC system was optimized by using the Arizona phase system, to enrich the extract in anthraquinones. Two systems were selected to isolate the bioactive compounds from the oily extract with varied purity target. The effect of the injection mode for these very viscous samples was also studied. Finally, in order to directly apply a selective process of extraction to the seeds, the super/subcritical fluid extraction was optimized to increase the anthraquinone yield in the final extract, by studying varied modifier compositions and nature, as well as different temperatures and backpressures. Conditions suited to favour an enrichment factor bases on the ratio of anthraquinone and trilycerides extracted are

  3. [Selective enrichment of Pseudomonas spp. in the rhizoplane of different plant species].

    PubMed

    Marrero, Mariana A; Agaras, Betina; Wall, Luis G; Valverde, Claudio

    2015-01-01

    In contrast to rhizobia-legume symbiosis, the specificity for root colonization by pseudomonads seems to be less strict. However, several studies about bacterial diversity in the rhizosphere highlight the influence of plant species on the selective enrichment of certain microorganisms from the bulk soil community. In order to evaluate the effect that different crops have on the structure of pseudomonad community on the root surface, we performed plant trap experiments, using surface-disinfected maize, wheat or soybean seeds that were sown in pots containing the same pristine soil as substrate. Rhizoplane suspensions were plated on a selective medium for Pseudomonas, and pooled colonies served as DNA source to carry out PCR-RFLP community structure analysis of the pseudomonads-specific marker genes oprF and gacA. PCR-RFLP profiles were grouped by plant species, and were distinguished from those of bulk soil samples. Partial sequencing of 16S rDNA genes of some representative colonies of Pseudomonas confirmed the selective enrichment of distinctive genotypes in the rhizoplane of each plant species. These results support the idea that the root systems of agricultural crops such as soybean, maize and wheat, select differential sets of pseudomonads from the native microbial repertoire inhabiting the bulk soil. PMID:26054776

  4. Selective enrichment of microRNAs in extracellular matrix vesicles produced by growth plate chondrocytes.

    PubMed

    Lin, Zhao; Rodriguez, Nicholas E; Zhao, Junjun; Ramey, Allison N; Hyzy, Sharon L; Boyan, Barbara D; Schwartz, Zvi

    2016-07-01

    Matrix vesicles (MVs) are membrane organelles found in the extracellular matrix of calcifying cells, which contain matrix processing enzymes and regulate the extracellular environment via action of these enzymes. It is unknown whether MVs are also exosomic mediators of cell-cell communication via transfer of RNA material, and specifically, microRNA (miRNA). We investigated the presence of RNA in MVs isolated from cultures of costochondral growth zone chondrocytes. Our results showed that the average yield of MV RNA was 1.93±0.78ng RNA/10(4) cells, which was approximately 0.1% of the parent cell's total RNA. MV RNA was well-protected from RNase by the lipid membrane and was highly enriched in small RNA molecules compared to cells. Moreover, coding and non-coding small RNAs in MVs were in proportions that differed from parent cells. Enrichment of specific miRNAs was consistently observed in all three miRNA detection platforms that we used, suggesting that miRNAs are selectively packaged into MVs. MV-enriched miRNAs were related to different signaling pathways associated with bone formation. This study suggests a significant role for MVs as "matrisomes" in cell-cell communication in cartilage and bone development via transfer of specific miRNAs. PMID:27080510

  5. Survival of the fastest: Selective removal of the side population for enhanced PHA production in a mixed substrate enrichment.

    PubMed

    Korkakaki, Emmanouela; van Loosdrecht, Mark C M; Kleerebezem, Robbert

    2016-09-01

    The success of enriching PHA-producers in a feast/famine regime strongly depends on the substrate utilized. A distinction can be made between substrates that select for PHA-producers (e.g. volatile fatty acids) and substrates that select for growing organisms (e.g. methanol). In this study the feasibility of using such a mixed substrate was evaluated. A sedimentation step was introduced in the cycle after acetate depletion and the supernatant containing methanol was discharged. This process configuration resulted in an increased maximum PHA storage capacity of the biomass from 48wt% to 70wt%. A model based on the experimental results indicated that the length of the pre-settling period and the supernatant volume that is discharged play a significant role for the elimination of the side population. However, the kinetic properties of the two different populations determine the success of the proposed strategy. PMID:27343455

  6. Polyethyleneimine-grafted boronate affinity materials for selective enrichment of cis-diol-containing compounds.

    PubMed

    Xue, Yun; Shi, Wenjun; Zhu, Bangjie; Gu, Xue; Wang, Yan; Yan, Chao

    2015-08-01

    Polyethyleneimine (PEI)-grafted and 3-acrylamidophenylboronic acid (AAPBA)-functionalized SiO2 boronate affinity materials were synthesized for the selective enrichment of cis-diol-containing compounds. Characterization results of scanning electron microscopy, Fourier transform infrared spectroscopy, elemental analysis, zeta potential, and X-ray photoelectron spectroscopy indicated the successful fabrication of SiO2@PEI-AAPBA materials. Chromatographic separation of test mixtures reveals that SiO2@PEI-AAPBA has high selective enrichment ability for cis-diol-containing compounds. The binding pH between SiO2@PEI-AAPBA and catechol was found to be as low as pH 4.5, while that between SiO2@PEI-AAPBA and adenosine was only ~7.5. This difference might be attributed to the strong electrostatic repulsion between the solid phase and analytes at a low pH. Furthermore, a diphasic separation column was fabricated based on boronate affinity chromatography, C18-reversed-phase chromatography and applied in pressurized capillary electrochromatography (pCEC). Results showed that four polar nucleosides could be well captured by the boronate affinity chromatography (BAC) section and separated by reversed phase pCEC. Finally, SiO2@PEI600-AAPBA-based solid-phase extraction technology was applied to the purification of ribonucleosides in real urine samples, and results of UHPLC-MS/MS revealed that the intensities of the extracted ions (a neutral mass loss of m/z 132.04 Da) of the ribonucleosides were significantly enhanced after the enrichment. PMID:26048816

  7. Chasing Phosphoarginine Proteins: Development of a Selective Enrichment Method Using a Phosphatase Trap*

    PubMed Central

    Trentini, Débora Broch; Fuhrmann, Jakob; Mechtler, Karl; Clausen, Tim

    2014-01-01

    Arginine phosphorylation is an emerging post-translational protein modification implicated in the bacterial stress response. Although early reports suggested that arginine phosphorylation also occurs in higher eukaryotes, its overall prevalence was never studied using modern mass spectrometry methods, owing to technical difficulties arising from the acid lability of phosphoarginine. As shown recently, the McsB and YwlE proteins from Bacillus subtilis function as a highly specific protein arginine kinase and phosphatase couple, shaping the phosphoarginine proteome. Using a B. subtilis ΔywlE strain as a source for arginine-phosphorylated proteins, we were able to adapt mass spectrometry (MS) protocols to the special chemical properties of the arginine modification. Despite this progress, the analysis of protein arginine phosphorylation in eukaryotes is still challenging, given the great abundance of serine/threonine phosphorylations that would compete with phosphoarginine during the phosphopeptide enrichment procedure, as well as during data-dependent MS acquisition. We thus set out to establish a method for the selective enrichment of arginine-phosphorylated proteins as an initial step in the phosphoproteomic analysis. For this purpose, we developed a substrate-trapping mutant of the YwlE phosphatase that retains binding affinity toward arginine-phosphorylated proteins but cannot hydrolyze the captured substrates. By testing a number of active site substitutions, we identified a YwlE mutant (C9A) that stably binds to arginine-phosphorylated proteins. We further improved the substrate-trapping efficiency by impeding the oligomerization of the phosphatase mutant. The engineered YwlE trap efficiently captured arginine-phosphorylated proteins from complex B. subtilis ΔywlE cell extracts, thus facilitating identification of phosphoarginine sites in the large pool of cellular protein modifications. In conclusion, we present a novel tool for the selective enrichment and

  8. Highly selective enrichment of phosphopeptides with high-index facets exposed octahedral tin dioxide nanoparticles for mass spectrometric analysis.

    PubMed

    Ma, Rongna; Hu, Junjie; Cai, Zongwei; Ju, Huangxian

    2014-02-01

    High-index facets exposed octahedral tin dioxide (SnO2) nanoparticles were successfully synthesized and applied to selectively enrich phosphopeptides for mass spectrometric analysis. The high selectivity and capacity of the octahedral SnO2 nanoparticles were demonstrated by effectively enriching phosphopeptides from digests of phosphoprotein (α- or β-casein), protein mixtures of β-casein and bovine serum albumin, milk, and human serum samples. The unique octahedral SnO2 with abundant unsaturated coordination Sn atoms exhibited enhanced affinity and selective coordination ability with phosphopeptides due to their high chemical activity. The strong affinity led to highly selective capture and enrichment of phosphopeptides for sensitive detection through the bidentate bonds formed between surface atoms and phosphate. The phosphopeptides could be detected in β-casein down to 4 × 10(-9)M or in the mixture of β-casein and BSA with a molar ratio of even 1:100. The performance in selective enrichment of phosphopeptides from drinking milk and human serum showed powerful evidence of high selectivity and efficiency in identifying the low-abundant phosphopeptides from complicated biological samples. This work provided a way to improve the physical and chemical properties of materials by tailoring their exposed facets for selective enrichment of phosphopeptides. PMID:24401440

  9. Selective Enrichment of Omega-3 Fatty Acids in Oils by Phospholipase A1.

    PubMed

    Ranjan Moharana, Tushar; Byreddy, Avinesh R; Puri, Munish; Barrow, Colin; Rao, Nalam Madhusudhana

    2016-01-01

    Omega fatty acids are recognized as key nutrients for healthier ageing. Lipases are used to release ω-3 fatty acids from oils for preparing enriched ω-3 fatty acid supplements. However, use of lipases in enrichment of ω-3 fatty acids is limited due to their insufficient specificity for ω-3 fatty acids. In this study use of phospholipase A1 (PLA1), which possesses both sn-1 specific activity on phospholipids and lipase activity, was explored for hydrolysis of ω-3 fatty acids from anchovy oil. Substrate specificity of PLA1 from Thermomyces lenuginosus was initially tested with synthetic p-nitrophenyl esters along with a lipase from Bacillus subtilis (BSL), as a lipase control. Gas chromatographic characterization of the hydrolysate obtained upon treatment of anchovy oil with these enzymes indicated a selective retention of ω-3 fatty acids in the triglyceride fraction by PLA1 and not by BSL. 13C NMR spectroscopy based position analysis of fatty acids in enzyme treated and untreated samples indicated that PLA1 preferably retained ω-3 fatty acids in oil, while saturated fatty acids were hydrolysed irrespective of their position. Hydrolysis of structured triglyceride,1,3-dioleoyl-2-palmitoylglycerol, suggested that both the enzymes hydrolyse the fatty acids at both the positions. The observed discrimination against ω-3 fatty acids by PLA1 appears to be due to its fatty acid selectivity rather than positional specificity. These studies suggest that PLA1 could be used as a potential enzyme for selective concentrationof ω-3 fatty acids. PMID:26978518

  10. Selective Enrichment of Omega-3 Fatty Acids in Oils by Phospholipase A1

    PubMed Central

    Puri, Munish; Barrow, Colin; Rao, Nalam Madhusudhana

    2016-01-01

    Omega fatty acids are recognized as key nutrients for healthier ageing. Lipases are used to release ω-3 fatty acids from oils for preparing enriched ω-3 fatty acid supplements. However, use of lipases in enrichment of ω-3 fatty acids is limited due to their insufficient specificity for ω-3 fatty acids. In this study use of phospholipase A1 (PLA1), which possesses both sn-1 specific activity on phospholipids and lipase activity, was explored for hydrolysis of ω-3 fatty acids from anchovy oil. Substrate specificity of PLA1 from Thermomyces lenuginosus was initially tested with synthetic p-nitrophenyl esters along with a lipase from Bacillus subtilis (BSL), as a lipase control. Gas chromatographic characterization of the hydrolysate obtained upon treatment of anchovy oil with these enzymes indicated a selective retention of ω-3 fatty acids in the triglyceride fraction by PLA1 and not by BSL. 13C NMR spectroscopy based position analysis of fatty acids in enzyme treated and untreated samples indicated that PLA1 preferably retained ω-3 fatty acids in oil, while saturated fatty acids were hydrolysed irrespective of their position. Hydrolysis of structured triglyceride,1,3-dioleoyl-2-palmitoylglycerol, suggested that both the enzymes hydrolyse the fatty acids at both the positions. The observed discrimination against ω-3 fatty acids by PLA1 appears to be due to its fatty acid selectivity rather than positional specificity. These studies suggest that PLA1 could be used as a potential enzyme for selective concentrationof ω-3 fatty acids. PMID:26978518

  11. Zirconium-doped magnetic microspheres for the selective enrichment of cis-diol-containing ribonucleosides.

    PubMed

    Fan, Hua; Chen, Peihong; Wang, Chaozhan; Wei, Yinmao

    2016-05-27

    Zirconium-doped magnetic microspheres (Zr-Fe3O4) for the selective enrichment of cis-diol-containing biomolecules were easily synthesized via a one-step hydrothermal method. Characterization of the microspheres revealed that zirconium was successfully doped into the lattice of Fe3O4 at a doping level of 4.0 at%. Zr-Fe3O4 possessed good magnetic properties and high specificity towards cis-diol molecules, as shown using 28 compounds. For ribonucleosides, the adsorbent not only has favorable anti-interferential abilities but also has a high adsorption capacity up to 159.4μmol/g. As an example of a real application, four ribonucleosides in urine were efficiently enriched and detected via magnetic solid-phase extraction coupled with high-performance liquid chromatography. Under the optimized extraction conditions, the detection limits were determined to be between 0.005 and 0.017μg/mL, and the linearities ranged from 0.02 to 5.00μg/mL (R≥0.996) for these analytes. The accuracy of the analytical method was examined by studying the relative recoveries of the analytes in real urine samples, with recoveries varying from 77.8% to 119.6% (RSDs<10.6%, n=6). The results indicate that Zr-Fe3O4 is a suitable adsorbent for the analysis of cis-diol-containing biomolecules in practical applications. PMID:27130580

  12. The Use of Titanium Dioxide for Selective Enrichment of Phosphorylated Peptides.

    PubMed

    Thingholm, Tine E; Larsen, Martin R

    2016-01-01

    Titanium dioxide (TiO2) has very high affinity for phosphopeptides and in recent years it has become one of the most popular methods for phosphopeptide enrichment from complex biological samples. Peptide loading onto TiO2 resin in a highly acidic environment in the presence of 2,5-dihydroxybenzoic acid (DHB), phthalic acid, lactic acid, or glycolic acid has been shown to improve selectivity significantly by reducing unspecific binding of non-phosphorylated peptides. The phosphopeptides bound to the TiO2 are subsequently eluted from the chromatographic material using an alkaline buffer. TiO2 chromatography is extremely tolerant towards most buffers used in biological experiments, highly robust and as such it has become the method of choice in large-scale phosphoproteomics. Here we describe a batch mode protocol for phosphopeptide enrichment using TiO2 chromatographic material followed by desalting and concentration of the sample by reversed phase micro-columns prior to downstream MS and LC-MS/MS analysis. PMID:26584923

  13. Selective enrichment and production of highly urease active bacteria by non-sterile (open) chemostat culture.

    PubMed

    Cheng, Liang; Cord-Ruwisch, Ralf

    2013-10-01

    In general, bioprocesses can be subdivided into naturally occurring processes, not requiring sterility (e.g., beer brewing, wine making, lactic acid fermentation, or biogas digestion) and other processes (e.g., the production of enzymes and antibiotics) that typically require a high level of sterility to avoid contaminant microbes overgrowing the production strain. The current paper describes the sustainable, non-sterile production of an industrial enzyme using activated sludge as inoculum. By using selective conditions (high pH, high ammonia concentration, and presence of urea) for the target bacterium, highly active ureolytic bacteria, physiologically resembling Sporosarcina pasteurii were reproducibly enriched and then continuously produced via chemostat operation of the bioreactor. When using a pH of 10 and about 0.2 M urea in a yeast extract-based medium, ureolytic bacteria developed under aerobic chemostat operation at hydraulic retention times of about 10 h with urease levels of about 60 μmol min⁻¹ ml⁻¹ culture. For cost minimization at an industrial scale the costly protein-rich yeast extract medium could be replaced by commercial milk powder or by lysed activated sludge. Glutamate, molasses, or glucose-based media did not result in the enrichment of ureolytic bacteria by the chemostat. The concentration of intracellular urease was sufficiently high such that the produced raw effluent from the reactor could be used directly for biocementation in the field. PMID:23892419

  14. Increase of Natural 15N Enrichment of Soybean Nodules with Mean Nodule Mass 1

    PubMed Central

    Shearer, Georgia; Bryan, Barbara A.; Kohl, Daniel H.

    1984-01-01

    The 15N abundance of soybean (Glycine max L. Merrill var Harosoy) nodules is usually greater than it is for other tissues or for atmospheric N2. Results of experiments in which nodules were separated by size show that the magnitude of the 15N enrichment is correlated with nodule mass. The results support the hypothesis that 15N enrichment of nodules results from differential N isotopic fractionation for synthesis of nodule tissue versus synthesis of compounds for export from the nodule. The physiological significance of this hypothesis is that it requires that a substantial fraction of the N for nodule tissue synthesis in 15N-enriched nodules be N recently fixed within the same nodule. PMID:16663917

  15. An Elementary Overview of the Selection of Materials for Service in Oxygen-Enriched Environments

    NASA Technical Reports Server (NTRS)

    Davis, Samuel Eddie

    2012-01-01

    The process for selecting materials for use in oxygen or oxygen-enriched environments is one that continues to be investigated by many industries due to the importance to those industries of oxygen systems. There are several excellent resources available to assist oxygen systems design engineers and end-users, with the most comprehensive being ASTM MNL-36, Safe Use of Oxygen and Oxygen Systems: Handbook for Design, Operation and Maintenance, 2nd Edition. ASTM also makes available several standards for oxygen systems. However, the ASTM publications are extremely detailed, and typically designed for professionals who already possess a working knowledge of oxygen systems. No notable resource exists, whether an ASTM or other organizational publication, which can be used to educate engineers or technicians who have no prior knowledge of the nuances of oxygen system design and safety. This paper will fill the void for information needed by organizations that design or operate oxygen systems. The information in this paper is not new information, but is a concise and easily understood summary of selecting materials for oxygen systems. This paper will serve well as an employee s first introduction to oxygen system materials selection, and probably the employee s first introduction to ASTM.

  16. An Enriched Research Experience for Minority Undergraduates--A Step toward Increasing the Number of Minority Nurse Researchers.

    ERIC Educational Resources Information Center

    Leeman, Jennifer; Goeppinger, Jean; Funk, Sandra; Roland, E. Joyce

    2003-01-01

    A partnership between a research university and a minority-serving institution created a research enrichment and apprenticeship program for minority nursing students. The program provides students an opportunity to experience nursing research with the goal of increasing the number of minority researchers in nursing. (Contains 11 references.) (JOW)

  17. CO₂ enrichment can produce high red leaf lettuce yield while increasing most flavonoid glycoside and some caffeic acid derivative concentrations.

    PubMed

    Becker, Christine; Kläring, Hans-Peter

    2016-05-15

    Carbon dioxide (CO2) enrichment is a common practice in greenhouses to increase crop yields up to 30%. Yet, reports on the effect on foliar phenolic compounds vary. We studied the effect on two red leaf lettuce cultivars, grown for 25 days in growth chambers at CO2 concentrations of 200 or 1,000 ppm, with some plants exchanged between treatments after 11 days. As expected, head mass increased with higher CO2 concentration. Regression analysis, corrected for head mass, showed increased concentrations of most flavonoid glycosides at high CO2 concentrations while only some caffeic acid derivatives were increased, and not uniformly in both cultivars. Sugar concentrations increased with CO2 concentration. Generally, conditions in the 10 days before harvest determined concentrations. We suspect that phenolic compounds were mainly accumulated because plenty of precursors were available. The results indicate that CO2 enrichment can result in high yields of red leaf lettuce rich in phenolic compounds. PMID:26776031

  18. Development of erbium phosphate doped poly(glycidyl methacrylate/ethylene dimethacrylate) spin columns for selective enrichment of phosphopeptides.

    PubMed

    Güzel, Yüksel; Rainer, Matthias; Messner, Christoph B; Hussain, Shah; Meischl, Florian; Sasse, Michael; Tessadri, Richard; Bonn, Günther K

    2015-05-01

    In this study, a novel method for the highly selective enrichment of phosphopeptides using erbium phosphate doped poly(glycidyl methacrylate/ethylene dimethacrylate) spin columns is presented. Erbium phosphate was synthesized by precipitation from boiling phosphoric acid and incubated overnight in erbium chloride solutions. The resulting powder was embedded in a monolithic poly(glycidyl methacrylate/ethylene dimethacrylate) polymer. The monolith was synthesized in a spin column by radical polymerization. Erbium phosphate demonstrated a high affinity and selectivity for phosphopeptides due to the strong interaction of trivalent erbium ions with the phosphate groups of phosphopeptides. The high selectivity and performance of the designed spin columns were demonstrated by successfully enriching phosphopeptides from tryptically digested protein mixtures containing the model phosphoproteins α- and β-casein, bovine milk, and human saliva. By the implementation of several washing steps, unspecific components were removed and the enriched phosphopeptides were effectively eluted from the spin columns under alkaline conditions. The selective performance of the presented method was further demonstrated by the enrichment of two synthetic phosphopeptides, which were spiked in tryptically digested and dephosphorylated HeLa cell lysates at low ratios. Finally, the presented approach was compared to conventional phosphopeptide enrichment by titanium oxide and revealed higher recoveries for the erbium phosphate doped monoliths. PMID:25645427

  19. Preparation of mixed lanthanides-immobilized magnetic nanoparticles for selective enrichment and identification of phosphopeptides by MS.

    PubMed

    Zhai, Rui; Jiao, Fenglong; Feng, Duan; Hao, Feiran; Li, Jiabin; Li, Nannan; Yan, Hui; Wang, Huanhuan; Jin, Zuyao; Zhang, Yangjun; Qian, Xiaohong

    2014-12-01

    A new type of mixed lanthanides-immobilized (Tb(3+) , Tm(3+) , Ho(3+) , Lu(3+) ) magnetic nanoparticles, Fe3 O4 @TCPP-DOTA-M(3+) , was prepared with a particle size of approximately 30 nm. A model protein, α-casein, and a protein mixture of α-casein and BSA (1:100) were first used to test the phosphopeptide enrichment efficiency of the newly developed magnetic nanoparticles. For the model protein α-casein, 19 phosphopeptides were identified with the newly developed materials. Even in the tryptic digest of α-casein and BSA (1:100), 16 phosphopeptides were easily detected, suggesting that the novel materials possess high selectivity in phosphopeptide enrichment. To evaluate the phosphopeptide enrichment efficiency in a real biological sample, the materials were used to capture phosphopeptides in the tryptic digests of an extract of HeLa cells. In total, 9048 phosphopeptides corresponding to 2103 phosphoproteins were identified in a single mass spectrometric analysis, indicating the great potential of the new materials for practical applications. Compared with metal oxide-based enrichment methods, the newly developed materials are convenient to prepare and easy to handle, and they save time in the phosphopeptide enrichment procedure, making these materials a good choice for highly selective and sensitive phosphopeptide enrichment in future phosphoproteome analyses. PMID:24846711

  20. Selective chemoprecipitation to enrich nitropeptides from complex proteomes for mass-spectrometric analysis.

    PubMed

    Prokai, Laszlo; Guo, Jia; Prokai-Tatrai, Katalin

    2014-04-01

    Post-translational protein nitration has attracted interest owing to its involvement in cellular signaling, effects on protein function and potential as biomarker of nitroxidative stress. We describe a procedure for enriching nitropeptides for mass spectrometry (MS)-based proteomics that is a simple and reliable alternative to immunoaffinity-based methods. The starting material for this procedure is a proteolytic digest. The peptides are reacted with formaldehyde and sodium cyanoborohydride to dimethylate all the N-terminal and side chain amino groups. Sodium dithionite is added subsequently to reduce the nitro groups to amines; in theory, the only amino groups present will have originally been nitro groups. The peptide sample is then applied to a solid-phase active ester reagent (SPAER), and those peptides with amino groups will be selectively and covalently captured. Release of the peptides on hydrolysis with trifluoroacetic acid (TFA) results in peptides that have a 4-formyl-benzamido group where the nitro group used to be. In qualitative setups, the procedure can be used to identify proteins modified by reactive nitrogen species and to determine the specific sites of their nitration. Quantitative measurements can be performed by stable-isotope labeling of the peptides in the reductive dimethylation step. Preparation of the SPAER takes about 1 d. Enrichment of nitropeptides requires about 2 d, and sample preparations need 1-30 h, depending on the experimental design. LC-MS/MS assays take from 4 h to several days and data processing can be done in 1-7 d. PMID:24651500

  1. High molecular weight dissolved organic matter enrichment selects for methylotrophs in dilution to extinction cultures

    PubMed Central

    Sosa, Oscar A; Gifford, Scott M; Repeta, Daniel J; DeLong, Edward F

    2015-01-01

    The role of bacterioplankton in the cycling of marine dissolved organic matter (DOM) is central to the carbon and energy balance in the ocean, yet there are few model organisms available to investigate the genes, metabolic pathways, and biochemical mechanisms involved in the degradation of this globally important carbon pool. To obtain microbial isolates capable of degrading semi-labile DOM for growth, we conducted dilution to extinction cultivation experiments using seawater enriched with high molecular weight (HMW) DOM. In total, 93 isolates were obtained. Amendments using HMW DOM to increase the dissolved organic carbon concentration 4x (280 μM) or 10x (700 μM) the ocean surface water concentrations yielded positive growth in 4–6% of replicate dilutions, whereas <1% scored positive for growth in non-DOM-amended controls. The majority (71%) of isolates displayed a distinct increase in cell yields when grown in increasing concentrations of HMW DOM. Whole-genome sequencing was used to screen the culture collection for purity and to determine the phylogenetic identity of the isolates. Eleven percent of the isolates belonged to the gammaproteobacteria including Alteromonadales (the SAR92 clade) and Vibrio. Surprisingly, 85% of isolates belonged to the methylotrophic OM43 clade of betaproteobacteria, bacteria thought to metabolically specialize in degrading C1 compounds. Growth of these isolates on methanol confirmed their methylotrophic phenotype. Our results indicate that dilution to extinction cultivation enriched with natural sources of organic substrates has a potential to reveal the previously unsuspected relationships between naturally occurring organic nutrients and the microorganisms that consume them. PMID:25978545

  2. High molecular weight dissolved organic matter enrichment selects for methylotrophs in dilution to extinction cultures.

    PubMed

    Sosa, Oscar A; Gifford, Scott M; Repeta, Daniel J; DeLong, Edward F

    2015-12-01

    The role of bacterioplankton in the cycling of marine dissolved organic matter (DOM) is central to the carbon and energy balance in the ocean, yet there are few model organisms available to investigate the genes, metabolic pathways, and biochemical mechanisms involved in the degradation of this globally important carbon pool. To obtain microbial isolates capable of degrading semi-labile DOM for growth, we conducted dilution to extinction cultivation experiments using seawater enriched with high molecular weight (HMW) DOM. In total, 93 isolates were obtained. Amendments using HMW DOM to increase the dissolved organic carbon concentration 4x (280 μM) or 10x (700 μM) the ocean surface water concentrations yielded positive growth in 4-6% of replicate dilutions, whereas <1% scored positive for growth in non-DOM-amended controls. The majority (71%) of isolates displayed a distinct increase in cell yields when grown in increasing concentrations of HMW DOM. Whole-genome sequencing was used to screen the culture collection for purity and to determine the phylogenetic identity of the isolates. Eleven percent of the isolates belonged to the gammaproteobacteria including Alteromonadales (the SAR92 clade) and Vibrio. Surprisingly, 85% of isolates belonged to the methylotrophic OM43 clade of betaproteobacteria, bacteria thought to metabolically specialize in degrading C1 compounds. Growth of these isolates on methanol confirmed their methylotrophic phenotype. Our results indicate that dilution to extinction cultivation enriched with natural sources of organic substrates has a potential to reveal the previously unsuspected relationships between naturally occurring organic nutrients and the microorganisms that consume them. PMID:25978545

  3. COLD-PCR enriches low-level variant DNA sequences and increases the sensitivity of genetic testing.

    PubMed

    Castellanos-Rizaldos, Elena; Milbury, Coren A; Guha, Minakshi; Makrigiorgos, G Mike

    2014-01-01

    Detection of low-level mutations is important for cancer biomarker and therapy targets discovery, but reliable detection remains a technical challenge. The newly developed method of CO-amplification at Lower Denaturation temperature PCR (COLD-PCR) helps to circumvent this issue. This PCR-based technology preferentially enriches minor known or unknown variants present in samples with a high background of wild type DNA which often hampers the accurate identification of these minority alleles. This is a simple process that consists of lowering the temperature at the denaturation step during the PCR-cycling protocol (critical denaturation temperature, T c) and inducing DNA heteroduplexing during an intermediate step. COLD-PCR in its simplest forms does not need additional reagents or specific instrumentation and thus, can easily replace conventional PCR and at the same time improve the mutation detection sensitivity limit of downstream technologies. COLD-PCR can be applied in two basic formats: fast-COLD-PCR that can enrich T m-reducing mutations and full-COLD-PCR that can enrich all mutations, though it requires an intermediate cross-hybridization step that lengthens the thermocycling program. An improved version of full-COLD-PCR (improved and complete enrichment, ice-COLD-PCR) has also been described. Finally, most recently, we developed yet another form of COLD-PCR, temperature-tolerant-COLD-PCR, which gradually increases the denaturation temperature during the COLD-PCR reaction, enriching diverse targets using a single cycling program. This report describes practical considerations for application of fast-, full-, ice-, and temperature-tolerant-COLD-PCR for enrichment of mutations prior to downstream screening. PMID:24259002

  4. Detection of Burkholderia pseudomallei in Sputum using Selective Enrichment Broth and Ashdown's Medium at Kampong Cham Provincial Hospital, Cambodia.

    PubMed

    Nhem, Somary; Letchford, Joanne; Meas, Chea; Thann, Sovanndeth; McLaughlin, James C; Baron, Ellen Jo; West, T Eoin

    2014-01-01

    Melioidosis, infection caused by Burkholderia pseudomallei, is increasingly reported in Cambodia. We hypothesized that implementation of an enhanced sputum testing protocol in a provincial hospital diagnostic microbiology laboratory would increase detection of B. pseudomallei. We tested 241 sputum specimens that were deemed acceptable for culture, comparing culture in selective enrichment broth followed by sub-culture on Ashdown's medium to standard culture methods. Two specimens (0.8%) were positive for B. pseudomallei using the enhanced protocol whereas one specimen (0.4%) was positive using standard methods. Given the low numbers of positive specimens, we could not conclusively determine the utility of the enhanced sputum testing protocol. However, the ramifications of identification of  B. pseudomallei are substantial, and the benefit of the enhanced testing protocol may be more apparent in patients selected based on risk factors and clinical presentation. Promoting clinician awareness of the infection and encouraging utilization of diagnostic microbiology services are also likely to be important factors in facilitating identification of melioidosis. PMID:25717370

  5. Magnetic metal-organic frameworks for selective enrichment and exclusion of proteins for MALDI-TOF MS analysis.

    PubMed

    Wan, Wei; Liang, Qionglin; Zhang, Xiaoqiong; Yan, Min; Ding, Mingyu

    2016-08-01

    We firstly report magnetic metal-organic frameworks for selective enrichment and exclusion of proteins for MALDI-TOF MS analysis. Fe3O4@MIL-100(Fe) nanoparticles were achieved by step-by-step assembly on poly(acrylic acid) modified Fe3O4. PMID:27350019

  6. New GO-PEI-Au-L-Cys ZIC-HILIC composites: synthesis and selective enrichment of glycopeptides.

    PubMed

    Jiang, Bo; Liang, Yu; Wu, Qi; Jiang, Hao; Yang, Kaiguang; Zhang, Lihua; Liang, Zhen; Peng, Xiaojun; Zhang, Yukui

    2014-06-01

    GO-PEI-Au-L-Cys composites were synthesized via loading gold nanoparticles on a GO surface using polyethylenimine as reducing and stabilizing reagents, followed by L-cysteine immobilization through an Au-S bond. The composites were applied as a kind of novel ZIC-HILIC material to achieve highly selective enrichment of glycopeptides from biological samples. PMID:24752239

  7. Increased physical activity is not enough to recover astrocytic population from dark-rearing. Synergy with multisensory enrichment is required.

    PubMed

    Bengoetxea, Harkaitz; Ortuzar, Naiara; Rico-Barrio, Irantzu; Lafuente, José Vicente; Argandoña, Enrike G

    2013-01-01

    Elimination of sensory inputs (deprivation) modifies the properties of the sensory cortex and serves as a model for studying plasticity during postnatal development. Many studies on the effects of deprivation have been performed in the visual cortex using dark-rearing as a visual deprivation model. It induces changes in all cellular and molecular components, including astrocytes, which play an important role in the development, maintenance, and plasticity of the cortex, mediated by cytokines which have been termed angioglioneurins. When one sense is deprived, a compensatory mechanism called cross-modal plasticity increases performance in the remaining senses. Environmental enrichment is so far the best-known method to compensate sensorial deprivation. The aim of this work is to study the effects of exercise alone, and of an enriched environment combined with exercise, on astroglial population in order to observe the effects of exercise by itself, or the potential synergistic effect during the rat visual system development. Pregnant Sprague-Dawley rats were raised in one of the following rearing conditions: in total darkness and enriched environment conditions with physical exercise, and in total darkness with voluntary physical exercise. Astrocytic density was estimated by immunohistochemistry for S-100β protein and quantifications were performed in layer IV. The somatosensorial cortex barrel field was also studied as control. Our main result shows that an enriched environment combined with voluntary physical exercise manages to reverse the negative effects induced by darkness over the astroglial population of both the visual and the somatosensory cortices. On the other hand, exercise alone only produces effects upon the astroglial population of the somatosensory cortex, and less so when combined with an enriched environment. PMID:24109431

  8. Self-Assembly-Assisted Biomolecule-Enriched Surface and High Selectivity Performance of Simple Solution-Coatable Biomimicking Brush Copolymers.

    PubMed

    Kwon, Kyungho; Kim, Changsub; Lee, Jongchan; Kim, Heesoo; Ree, Moonhor

    2016-03-14

    Poly(oxy(11-(biotinyl)undecylthiomethyl)ethylene-co-oxy(11-phosphoryl-cholineundecylthiomethyl)ethylene)s (PECH-BTmPCn: m = 0-100 mol % biotin (BT)-containing bristle; n = 100-0 mol % phosphorylcholine (PC)-containing bristle) were newly synthesized. All polymers exhibited excellent solution processability. They favorably self-assembled horizontal multibilayer structures in thin films with BT- and PC-enriched surfaces, which were driven by the lateral ordering of the fully extended upright bristles and the partial interdigitation between the BT and PC end groups of the bristles. Both hydrophilicity and water sorption of the films increased with the PC content. The PECH-BT100 films revealed remarkably distinctive sensitivity, selectivity, and adsorption ability for avidin against other proteins. Such remarkable performance was further significantly enhanced on the PECH-BTmPCn films in which PC moieties were incorporated to the BT-rich surface; in particular, the PECH-BT75PC25 films demonstrated the highest performance. Overall, the self-assembly brush copolymers of this study are very suitable for use in the high performance detection, adsorption, and separation of proteins and receptors, including avidin, which can reveal high affinity and selectivity to BT moiety. PMID:26809808

  9. Precollege enrichment programs intended to increase the representation of minorities in medicine.

    PubMed

    Carline, J D; Patterson, D G; Davis, L A; Irby, D M; Oakes-Borremo, P

    1998-03-01

    The authors reviewed the literature published from 1966 to 1996 to identify enrichment programs for underrepresented minority precollege students sponsored by medical schools and affiliated programs, finding 19 articles describing 27 programs. The authors categorized the reported programs according to the components they contained. Most programs contained more than one component type. Twenty-four programs had an academic enhancement component. Two thirds had a motivational component to encourage students to consider medical and other health careers. Two programs set up mentoring relationship between students and health professionals. There were four research apprenticeships and three academic partnerships between medical schools and local school districts. Twelve of the 27 programs were evaluated in the literature. Eight evaluations focused on identifying the numbers of students who continued their education into college and professional schools. Five programs reported participant satisfaction or identified other short-term outcomes such as gains on standardized tests. While the percentage of participants completing college and entering health care careers is impressive, the authors do not believe that the educational success of participants can be attributed to involvement in these programs. The authors recommend ways to improve the quality and interpretability of enrichment program evaluations. Evaluators should adopt common terminology for activities and outcomes. Participants' economic and educational disadvantages should be described. Programs' theoretical underpinnings should be identified and related to evaluation. Measures should include immediate effects as well as long-term outcomes. Where possible, data from comparison groups should be reported to support conclusions. Adequate funding needs to be available to design and complete reasonable evaluations. PMID:9526456

  10. Mobility-Selected Ion Trapping and Enrichment Using Structures for Lossless Ion Manipulations

    DOE PAGESBeta

    Chen, Tsung-Chi; Ibrahim, Yehia M.; Webb, Ian K.; Garimella, Sandilya V. B.; Zhang, Xing; Hamid, Ahmed M.; Deng, Liulin; Karnesky, William E.; Prost, Spencer A.; Sandoval, Jeremy A.; et al

    2016-01-11

    The integration of ion mobility spectrometry (IMS) with mass spectrometry (MS) and the ability to trap ions in IMS-MS measurements is of great importance for performing reactions, accumulating ions, and increasing analytical measurement sensitivity. The development of Structures for Lossless Ion Manipulations (SLIM) offers the potential for ion manipulations in a more reliable and cost-effective manner, while opening opportunities for much more complex sequences of manipulations. Here, we demonstrate an ion separation and trapping module and a method based upon SLIM that consists of a linear mobility ion drift region, a switch/tee and a trapping region that allows the isolationmore » and accumulation of mobility-separated species. The operation and optimization of the SLIM switch/tee and trap are described and demonstrated for the enrichment of the low abundance ions. Lastly, we observed a linear increase in ion intensity with the number of trapping/accumulation events using the SLIM trap, illustrating its potential for enhancing the sensitivity of low abundance or targeted species.« less

  11. Gold nanoparticles immobilized hydrophilic monoliths with variable functional modification for highly selective enrichment and on-line deglycosylation of glycopeptides.

    PubMed

    Liang, Yu; Wu, Ci; Zhao, Qun; Wu, Qi; Jiang, Bo; Weng, Yejing; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

    2015-11-01

    The poly (glycidyl methacrylate-co-poly (ethylene glycol) diacrylate) monoliths modified with gold nanoparticles, with advantages of enhanced reactive sites, good hydrophilicity and facile modification, were prepared as the matrix, followed by variable functionalization with cysteine and PNGase F for glycopeptide enrichment and on-line deglycosylation respectively. By the cysteine functionalized monolithic column, glycopeptides could be efficiently and selectively enriched with good reproducibility based on hydrophilic interaction chromatography (HILIC). Furthermore, the enrichment was specially achieved in weak alkaline environment, with 10 mM NH4HCO3 as the elution buffer, compatible with deglycosylation conditions. Therefore, the glycopeptides could be on-line deglycosylated with high efficiency and throughput by directly coupling the PNGase F functionalized monolithic column with the enrichment column during elution without the requirement of buffer exchange and pH adjustment. By such a method, within only 70-min pretreatment, 196 N-linked glycopeptides, corresponding to 122 glycoproteins, could be identified from 5 μg of human plasma with 14 high-abundant proteins removed, and the N-linked glycopeptides occupied 81% of all identified peptides, achieving to the best of our knowledge, the highest selectivity of HILIC-based methods. All the results demonstrated the high efficiency, selectivity and throughput of our proposed strategy for the large scale glycoproteome analysis. PMID:26572842

  12. Highly Selective Enrichment of Glycopeptides Based on Zwitterionically Functionalized Soluble Nanopolymers

    NASA Astrophysics Data System (ADS)

    Cao, Weiqian; Huang, Jiangming; Jiang, Biyun; Gao, Xing; Yang, Pengyuan

    2016-07-01

    Efficient glycopeptides enrichment prior to mass spectrometry analysis is essential for glycoproteome study. ZIC-HILIC (zwitterionic hydrophilic interaction liquid chromatography) based glycopeptides enrichment approaches have been attracting more attention for several benefits like easy operating, high enrichment specificity and intact glycopeptide retained. In this study, Poly (amidoamine) dendrimer (PAMAM) was adopted for the synthesis of zwitterionically functionalized (ZICF) materials for glycopeptide enrichment. The multiple branched structure and good solubility of ZICF-PAMAM enables a sufficient interaction with glycopeptides. The ZICF-PAMAM combined with the FASP-mode enrichment strategy exhibits more superior performance compared with the existing methods. It has the minimum detectable concentration of femtomolar level and high recovery rate of over 90.01%, and can efficiently enrich glycopeptides from complex biological samples even for merely 0.1 μL human serum. The remarkable glycopeptides enrichment capacity of ZICF-PAMAM highlights the potential application in in-depth glycoproteome research, which may open up new opportunities for the development of glycoproteomics.

  13. Highly Selective Enrichment of Glycopeptides Based on Zwitterionically Functionalized Soluble Nanopolymers.

    PubMed

    Cao, Weiqian; Huang, Jiangming; Jiang, Biyun; Gao, Xing; Yang, Pengyuan

    2016-01-01

    Efficient glycopeptides enrichment prior to mass spectrometry analysis is essential for glycoproteome study. ZIC-HILIC (zwitterionic hydrophilic interaction liquid chromatography) based glycopeptides enrichment approaches have been attracting more attention for several benefits like easy operating, high enrichment specificity and intact glycopeptide retained. In this study, Poly (amidoamine) dendrimer (PAMAM) was adopted for the synthesis of zwitterionically functionalized (ZICF) materials for glycopeptide enrichment. The multiple branched structure and good solubility of ZICF-PAMAM enables a sufficient interaction with glycopeptides. The ZICF-PAMAM combined with the FASP-mode enrichment strategy exhibits more superior performance compared with the existing methods. It has the minimum detectable concentration of femtomolar level and high recovery rate of over 90.01%, and can efficiently enrich glycopeptides from complex biological samples even for merely 0.1 μL human serum. The remarkable glycopeptides enrichment capacity of ZICF-PAMAM highlights the potential application in in-depth glycoproteome research, which may open up new opportunities for the development of glycoproteomics. PMID:27412817

  14. Highly Selective Enrichment of Glycopeptides Based on Zwitterionically Functionalized Soluble Nanopolymers

    PubMed Central

    Cao, Weiqian; Huang, Jiangming; Jiang, Biyun; Gao, Xing; Yang, Pengyuan

    2016-01-01

    Efficient glycopeptides enrichment prior to mass spectrometry analysis is essential for glycoproteome study. ZIC-HILIC (zwitterionic hydrophilic interaction liquid chromatography) based glycopeptides enrichment approaches have been attracting more attention for several benefits like easy operating, high enrichment specificity and intact glycopeptide retained. In this study, Poly (amidoamine) dendrimer (PAMAM) was adopted for the synthesis of zwitterionically functionalized (ZICF) materials for glycopeptide enrichment. The multiple branched structure and good solubility of ZICF-PAMAM enables a sufficient interaction with glycopeptides. The ZICF-PAMAM combined with the FASP-mode enrichment strategy exhibits more superior performance compared with the existing methods. It has the minimum detectable concentration of femtomolar level and high recovery rate of over 90.01%, and can efficiently enrich glycopeptides from complex biological samples even for merely 0.1 μL human serum. The remarkable glycopeptides enrichment capacity of ZICF-PAMAM highlights the potential application in in-depth glycoproteome research, which may open up new opportunities for the development of glycoproteomics. PMID:27412817

  15. Ciprofloxacin Residues in Municipal Biosolid Compost Do Not Selectively Enrich Populations of Resistant Bacteria

    PubMed Central

    Youngquist, Caitlin P.; Liu, Jinxin; Orfe, Lisa H.; Jones, Stephen S.

    2014-01-01

    Biosolids and livestock manure are valuable high-carbon soil amendments, but they commonly contain antibiotic residues that might persist after land application. While composting reduces the concentration of extractable antibiotics in these materials, if the starting concentration is sufficiently high then remaining residues could impact microbial communities in the compost and soil to which these materials are applied. To examine this issue, ciprofloxacin was added to biosolid compost feedstock to achieve a total concentration of 19 ppm, approximately 5-fold higher than that normally detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) (1 to 3.5 ppm). This feedstock was placed into mesh bags that were buried in aerated compost bays. Once a week, a set of bags was removed and analyzed (treated and untreated, three replicates of each; 4 weeks). Addition of ciprofloxacin had no effect on the recovery of resistant bacteria at any time point (P = 0.86), and a separate bioassay showed that aqueous extractions from materials with an estimated 59 ppm ciprofloxacin had no effect on the growth of a susceptible strain of Escherichia coli (P = 0.28). Regression analysis showed that growth of the susceptible strain of E. coli can be reduced given a sufficiently high concentration of ciprofloxacin (P < 0.007), a result that is consistent with adsorption being the primary mechanism of sequestration. While analytical methods detected biologically significant concentrations of ciprofloxacin in the materials tested here, the culture-based methods were consistent with the materials having sufficient adsorptive capacity to prevent typical concentrations of ciprofloxacin residues from selectively enriching populations of resistant bacteria. PMID:25261519

  16. CO2 enrichment increases carbon and nitrogen input from fine roots in a deciduous forest.

    SciTech Connect

    Iversen, Colleen M; Childs, Joanne; Norby, Richard J

    2008-08-01

    Greater root production under elevated [CO2] may drive changes in soil C storage and N cycling. However, this depends on root population turnover and chemistry, and the soil depth at which the roots are produced. We assessed the effect of elevated [CO2] on root biomass and N inputs at several soil depths using a long-term minirhizotron data set combined with continuous, root-specific measurements of root mass per unit length and [N]. Our experiment was conducted in a Liquidambar styraciflua forest stand exposed to current or elevated atmospheric [CO2] for 9 years. CO2-enrichment had no effect on root tissue density or [N] within a given diameter class. Root biomass production, standing crop and mortality were doubled under elevated [CO2]. Over 9 years, root mortality resulted in 681 g m-2 of extra C and 9 g m-2 of extra N input to the soil system under elevated [CO2]. At least half of these inputs were below 30 cm soil depth. Quantification of the effects of elevated CO2 on root detritus, especially at depth in the soil, will provide critical information needed for predicting processes such as long-term soil C storage and N cycling.

  17. A novel enrichment program using cascading mentorship to increase diversity in the health care professions.

    PubMed

    Afghani, Behnoosh; Santos, Rosanne; Angulo, Marco; Muratori, Walter

    2013-09-01

    The authors describe an innovative summer enrichment program based on a cascading mentorship model to transfer knowledge and skills from faculty to medical students to undergraduate students and finally to high school students. The program was designed to give high school students a glimpse of life in medical school and enhance the teaching and leadership skills of underrepresented undergraduate and medical students. Started in 2010 with 30 high school students and 9 college and medical student coaches, the University of California, Irvine, School of Medicine Summer Premed Program expanded rapidly over the next two summers and enrolled a total of 253 high school students, 48 college students, and 12 medical students. The college and medical student coaches, the majority of whom were underrepresented in medicine (URIM), reported that the program enhanced their teaching and leadership skills and self-confidence, motivated them toward careers in academic medicine, and raised their awareness about the importance of cultural diversity. The authors present the details of this interactive, structured program and describe how URIM student empowerment, near-peer teaching, science socialization, and support from the institution's leadership and faculty members provided a climate that fostered belonging, a sense of personal transformation, and professional development among students from different levels of education and diverse backgrounds. Long-term follow-up of the participants' career choices is needed. PMID:23887013

  18. The Selection, Training, and Certification of Facilitators for Marriage Enrichment Programs

    ERIC Educational Resources Information Center

    Mace, David; Mace, Vera

    1976-01-01

    As the marriage enrichment movement develops, nationally and internationally, the question of standards governing the services provided by leader couples becomes of critical importance. This paper examines the main programs now being offered. (Author)

  19. CO2 enrichment and N addition increase nutrient loss from decomposing leaf litter in subtropical model forest ecosystems

    PubMed Central

    Liu, Juxiu; Fang, Xiong; Deng, Qi; Han, Tianfeng; Huang, Wenjuan; Li, Yiyong

    2015-01-01

    As atmospheric CO2 concentration increases, many experiments have been carried out to study effects of CO2 enrichment on litter decomposition and nutrient release. However, the result is still uncertain. Meanwhile, the impact of CO2 enrichment on nutrients other than N and P are far less studied. Using open-top chambers, we examined effects of elevated CO2 and N addition on leaf litter decomposition and nutrient release in subtropical model forest ecosystems. We found that both elevated CO2 and N addition increased nutrient (C, N, P, K, Ca, Mg and Zn) loss from the decomposing litter. The N, P, Ca and Zn loss was more than tripled in the chambers exposed to both elevated CO2 and N addition than those in the control chambers after 21 months of treatment. The stimulation of nutrient loss under elevated CO2 was associated with the increased soil moisture, the higher leaf litter quality and the greater soil acidity. Accelerated nutrient release under N addition was related to the higher leaf litter quality, the increased soil microbial biomass and the greater soil acidity. Our results imply that elevated CO2 and N addition will increase nutrient cycling in subtropical China under the future global change. PMID:25608664

  20. CO2 enrichment and N addition increase nutrient loss from decomposing leaf litter in subtropical model forest ecosystems

    NASA Astrophysics Data System (ADS)

    Liu, Juxiu; Fang, Xiong; Deng, Qi; Han, Tianfeng; Huang, Wenjuan; Li, Yiyong

    2015-01-01

    As atmospheric CO2 concentration increases, many experiments have been carried out to study effects of CO2 enrichment on litter decomposition and nutrient release. However, the result is still uncertain. Meanwhile, the impact of CO2 enrichment on nutrients other than N and P are far less studied. Using open-top chambers, we examined effects of elevated CO2 and N addition on leaf litter decomposition and nutrient release in subtropical model forest ecosystems. We found that both elevated CO2 and N addition increased nutrient (C, N, P, K, Ca, Mg and Zn) loss from the decomposing litter. The N, P, Ca and Zn loss was more than tripled in the chambers exposed to both elevated CO2 and N addition than those in the control chambers after 21 months of treatment. The stimulation of nutrient loss under elevated CO2 was associated with the increased soil moisture, the higher leaf litter quality and the greater soil acidity. Accelerated nutrient release under N addition was related to the higher leaf litter quality, the increased soil microbial biomass and the greater soil acidity. Our results imply that elevated CO2 and N addition will increase nutrient cycling in subtropical China under the future global change.

  1. Predator fitness increases with selectivity for odd prey.

    PubMed

    Rutz, Christian

    2012-05-01

    The fundamental currency of normative models of animal decision making is Darwinian fitness. In foraging ecology, empirical studies typically assess foraging strategies by recording energy intake rates rather than realized reproductive performance. This study provides a rare empirical link, in a vertebrate predator-prey system, between a predator's foraging behavior and direct measures of its reproductive fitness. Goshawks Accipiter gentilis selectively kill rare color variants of their principal prey, the feral pigeon Columba livia, presumably because targeting odd-looking birds in large uniform flocks helps them overcome confusion effects and enhances attack success. Reproductive performance of individual hawks increases significantly with their selectivity for odd-colored pigeons, even after controlling for confounding age effects. Older hawks exhibit more pronounced dietary preferences, suggesting that hunting performance improves with experience. Intriguingly, although negative frequency-dependent predation by hawks exerts strong selection against rare pigeon phenotypes, pigeon color polymorphism is maintained through negative assortative mating. PMID:22503502

  2. Comprehensive evaluation of imidazole-based polymers for the enrichment of selected non-steroidal anti-inflammatory drugs.

    PubMed

    Schemeth, Dieter; Kappacher, Christoph; Rainer, Matthias; Thalinger, Ramona; Bonn, Günther K

    2016-06-01

    This study reports the comparison of four manufactured imidazole-based copolymers and two commercially available hydrophilic sorbents for the solid phase extraction (SPE) of selected non-steroidal anti-inflammatory drugs (NSAID). Different hydrophilic copolymers were obtained by a suspension polymerization using a styrene-based and a methacrylate-based cross-linker and by single step modifications for enhancing the ion-exchange character. SPE protocols were optimized for both non-modified and modified sorbents and applied for the enrichment of selected NSAID using all six copolymers. Comparison and evaluation were carried out by determining recovery rates of standard mixtures at different concentration levels ranging from 0.5mgL(-1) to 10mgL(-1) and by the enrichment of spiked human urine at two concentration levels. In order to gain insight into the complexity of the biological sample and its reduction after solid phase extraction, UHPLC-MS analysis and following database comparison was performed for the three mixed-mode strong anion-exchange sorbents. In order to prove the applicability of the modified imidazole-based polymers for the enrichment of NSAID in surface water, river water or groundwater, solid phase extraction was performed with 10ppb of NSAID which resulted into enhanced enrichment by a hundredfold. PMID:27130106

  3. Enrichments of Cellulolytic Communities from Diverse Natural Sources Using a Novel Selection System

    NASA Astrophysics Data System (ADS)

    Ludwig, Evan Joel

    In order to ensure a sustainable future and curb carbon dioxide emissions from the combustion of fossil fuels, it is imperative to develop a cost-competitive manufacturing process for an alternative liquid fuel with low life cycle greenhouse gas emissions. A potential route towards this sustainable future is the large-scale production of fuels derived from plant biomass, biofuels. A major step for the biological conversion of biomass to fuel is the solubilization and utilization of cellulose. However, lignocellulose is a recalcitrant material, and has evolved to resist microbial degradation. Studying cellulolytic communities from nature can reveal the mechanisms by which organisms can utilize lignocellulose, and also reveal the conditions that facilitate the fastest possible rates of cellulose utilization. This thesis used an Automated Repetitive Batch (ARB) system to perform enrichments of cellulolytic communities to test if cellulolytic communities from diverse sources could be reproducibly enriched for rapid cellulose utilization. This thesis first developed a robust method for reproducibly enriching cellulolytic communities in the ARB system with a single environmental source. Using this method, this research then investigated if cellulolytic communities could be enriched for rapid cellulose utilization from different inoculum sources. In all reproducible enrichments, this thesis then confirmed the use of carbon dioxide as a real time proxy for cellulose utilization based on end product analysis. This thesis showed that the ARB system could yield cellulolytic communities capable of rapid cellulose utilization from diverse environmental sources, and laid a strong foundation for determining whether or not these different sources can be enriched to yield functionally similar cellulolytic communities. The work from this thesis also suggests that fermentation conditions, rather than source material, play a more important role in determining enriched community

  4. Selective enrichment and identification of cross-linked peptides to study 3-D structures of protein complexes by mass spectrometry.

    PubMed

    Buncherd, Hansuk; Nessen, Merel A; Nouse, Niels; Stelder, Sacha K; Roseboom, Winfried; Dekker, Henk L; Arents, Jos C; Smeenk, Linde E; Wanner, Martin J; van Maarseveen, Jan H; Yang, Xiao; Lewis, Peter J; de Koning, Leo J; de Koster, Chris G; de Jong, Luitzen

    2012-04-01

    Chemical cross-linking of protein complexes combined with mass spectrometry is a powerful approach to obtain 3-D structural information by revealing amino residues that are in close spatial proximity. To increase the efficiency of mass spectrometric analysis, we have demonstrated the selective enrichment of cross-linked peptides from the 350 kDa protein complex RNA polymerase (RNAP) from Bacillus subtilis. Bis(succinimidyl)-3-azidomethyl glutarate was used as a cross-linker along with an azide-reactive cyclooctyne-conjugated resin to capture target peptides. Subsequently released peptides were fractionated by strong cation exchange chromatography and subjected to LC-MS/MS. We mapped 10 different intersubunit and 24 intrasubunit cross-links by xComb database searching supplied with stringent criteria for confirmation of the proposed structure of candidate cross-linked peptides. The cross-links fit into a homology model of RNAP. Cross-links between β lobe 1 and the β' downstream jaw, and cross-links involving the N-terminal and C-terminal parts of the α subunits suggest conformational flexibility. The analytical strategy presented here can be applied to map protein-protein interactions at the amino acid level in biological assemblies of similar complexity. Our approach enables the exploration of alternative peptide fragmentation techniques that may further facilitate cross-link analysis. PMID:22326961

  5. Designed synthesis of MOF-derived magnetic nanoporous carbon materials for selective enrichment of glycans for glycomics analysis.

    PubMed

    Sun, Nianrong; Zhang, Xiangmin; Deng, Chunhui

    2015-04-21

    In this work, magnetic nanoporous carbon (NPC) materials were synthesized by choosing a MOF as a sacrificial template and a carbon precursor. The obtained Co-ZIF-67 materials showed strong magnetic response, high surface area, a uniform size of mesopores and high carbon content. The Co-ZIF-67 materials were successfully applied to glycomics analysis by enriching N-linked glycans in bio-samples with high selectivity and efficiency. PMID:25805188

  6. A Method for Selective Enrichment and Analysis of Nitrotyrosine-Containing Peptides in Complex Proteome Samples

    SciTech Connect

    Zhang, Qibin; Qian, Weijun; Knyushko, Tanya V.; Clauss, Therese RW; Purvine, Samuel O.; Moore, Ronald J.; Sacksteder, Colette A.; Chin, Mark H.; Smith, Desmond J.; Camp, David G.; Bigelow, Diana J.; Smith, Richard D.

    2007-06-01

    Elevated levels of protein tyrosine nitration have been found in various neurodegenerative diseases and aging related pathologies; however, the lack of an efficient enrichment method has prevented the analysis of this important low level protein modification. We have developed an efficient method for specific enrichment of nitrotyrosine containing peptides that permits nitrotyrosine peptides and specific nitration sites to be unambiguously identified with LC-MS/MS. The method is based on the derivatization of nitrotyrosine into free sulfhydryl groups followed by high efficiency enrichment of sulfhydryl-containing peptides with thiopropyl sepharose beads. The derivatization process starts with acetylation with acetic anhydride to block all primary amines, followed by reduction of nitrotyrosine to aminotyrosine, then derivatization of aminotyrosine with N-Succinimidyl S-Acetylthioacetate (SATA), and finally deprotecting of S-acetyl on SATA to form free sulfhydryl groups. This method was evaluated using nitrotyrosine containing peptides, in-vitro nitrated human histone 1.2, and bovine serum albumin (BSA). 91% and 62% of the identified peptides from enriched histone and BSA samples were nitrotyrosine derivatized peptides, respectively, suggesting relative high specificity of the enrichment method. The application of this method to in-vitro nitrated mouse brain homogenate resulted in 35% of identified peptides containing nitrotyrosine (compared to only 5.9% observed from the global analysis of unenriched sample), and a total of 150 unique nitrated peptides covering 102 proteins were identified with a false discovery rate estimated at 3.3% from duplicate LC-MS/MS analyses of a single enriched sample.

  7. Selective enrichment of the degradation products of organophosphorus nerve agents by zirconia based solid-phase extraction.

    PubMed

    Kanaujia, Pankaj K; Pardasani, Deepak; Tak, Vijay; Purohit, Ajay K; Dubey, D K

    2011-09-23

    Selective extraction and enrichment of nerve agent degradation products has been achieved using zirconia based commercial solid-phase extraction cartridges. Target analytes were O-alkyl alkylphosphonic acids and alkylphosphonic acids, the environmental markers of nerve agents such as sarin, soman and VX. Critical extraction parameters such as modifier concentration, nature and volume of washing and eluting solvents were investigated. Amongst other anionic compounds, selectivity in extraction was observed for organophosphorus compounds. Recoveries of analytes were determined by GC-MS which ranged from 80% to 115%. Comparison of zirconia based solid-phase extraction method with anion-exchange solid-phase extraction revealed its selectivity towards phosphonic acids. The limits of detection (LOD) and limit of quantification (LOQ) with selected analytes were achieved down to 4.3 and 8.5 ng mL(-1), respectively, in selected ion monitoring mode. PMID:21862029

  8. Increased Liposome Extravasation in Selected Tissues: Effect of Substance P

    NASA Astrophysics Data System (ADS)

    Rosenecker, Joseph; Zhang, Weiming; Hong, Keelung; Lausier, James; Geppetti, Pierangelo; Yoshihara, Shigemi; Papahadjopoulos, Demetrios; Nadel, Jay A.

    1996-07-01

    We have used a pharmacologic mediator to open intercellular connections in selected vessels to allow liposomes to escape from the blood stream and to extravasate into tissues that have appropriate receptors. We have examined the effects of substance P (SP), a peptide known to increase vascular permeability in selected tissues, such as trachea, esophagus, and urinary bladder in rats. We used quantitative fluorescence analysis of tissues to measure two fluorescent markers, one attached to the lipid (rhodamine-phosphatidylethanolamine) and another, doxorubicin (an antitumor drug), encapsulated within the aqueous interior. We have also examined the deposition of liposomes microscopically by the use of encapsulated colloidal gold and silver enhancement. Analysis of the biochemical and morphological observations indicate the following: (i) Injection of SP produces a striking increase in both liposome labels, but only in tissues that possess receptors for SP in postcapillary venules; (ii) liposome material in these tissues has extravasated and is found extracellularly near a variety of cells beyond the endothelial layer over the first few hours; (iii) 24 h following injection of liposomes and SP, liposome material is found in these tissues, localized intracellularly in both endothelial cells and macrophages. We propose that appropriate application of tissue-specific mediators can result in liposome extravasation deep within tissues that normally do not take up significant amounts of liposomes from the blood. Such liposomes are able to carry a variety of pharmacological agents that can be released locally within selected target tissues for therapeutic purposes.

  9. CO2 enrichment increases element concentrations in grass mixtures by changing species abundances

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The continuing rise in atmospheric carbon dioxide (CO2) concentration may increase plant growth relatively more than the uptake of soil-derived chemical elements that are essential for herbivores. Rising CO2 also may alter the nutritional quality of forage or fodder derived from multi-species veget...

  10. Genetically engineered flavonol enriched tomato fruit modulates chondrogenesis to increase bone length in growing animals

    PubMed Central

    Choudhary, Dharmendra; Pandey, Ashutosh; Adhikary, Sulekha; Ahmad, Naseer; Bhatia, Chitra; Bhambhani, Sweta; Trivedi, Prabodh Kumar; Trivedi, Ritu

    2016-01-01

    Externally visible body and longitudinal bone growth is a result of proliferation of chondrocytes. In growth disorder, there is delay in the age associated increase in height. The present study evaluates the effect of extract from transgenic tomato fruit expressing AtMYB12 transcription factor on bone health including longitudinal growth. Constitutive expression of AtMYB12 in tomato led to a significantly enhanced biosynthesis of flavonoids in general and the flavonol biosynthesis in particular. Pre-pubertal ovary intact BALB/c mice received daily oral administration of vehicle and ethanolic extract of wild type (WT-TOM) and transgenic AtMYB12-tomato (MYB12-TOM) fruits for six weeks. Animal fed with MYB12-TOM showed no inflammation in hepatic tissues and normal sinusoidal Kupffer cell morphology. MYB12-TOM extract significantly increased tibial and femoral growth and subsequently improved the bone length as compared to vehicle and WT-TOM. Histomorphometry exhibited significantly wider distal femoral and proximal tibial growth plate, increased number and size of hypertrophic chondrocytes in MYB12-TOM which corroborated with micro-CT and expression of BMP-2 and COL-10, marker genes for hypertrophic cells. We conclude that metabolic reprogramming of tomato by AtMYB12 has the potential to improve longitudinal bone growth thus helping in achievement of greater peak bone mass during adolescence. PMID:26917158

  11. Genetically engineered flavonol enriched tomato fruit modulates chondrogenesis to increase bone length in growing animals.

    PubMed

    Choudhary, Dharmendra; Pandey, Ashutosh; Adhikary, Sulekha; Ahmad, Naseer; Bhatia, Chitra; Bhambhani, Sweta; Trivedi, Prabodh Kumar; Trivedi, Ritu

    2016-01-01

    Externally visible body and longitudinal bone growth is a result of proliferation of chondrocytes. In growth disorder, there is delay in the age associated increase in height. The present study evaluates the effect of extract from transgenic tomato fruit expressing AtMYB12 transcription factor on bone health including longitudinal growth. Constitutive expression of AtMYB12 in tomato led to a significantly enhanced biosynthesis of flavonoids in general and the flavonol biosynthesis in particular. Pre-pubertal ovary intact BALB/c mice received daily oral administration of vehicle and ethanolic extract of wild type (WT-TOM) and transgenic AtMYB12-tomato (MYB12-TOM) fruits for six weeks. Animal fed with MYB12-TOM showed no inflammation in hepatic tissues and normal sinusoidal Kupffer cell morphology. MYB12-TOM extract significantly increased tibial and femoral growth and subsequently improved the bone length as compared to vehicle and WT-TOM. Histomorphometry exhibited significantly wider distal femoral and proximal tibial growth plate, increased number and size of hypertrophic chondrocytes in MYB12-TOM which corroborated with micro-CT and expression of BMP-2 and COL-10, marker genes for hypertrophic cells. We conclude that metabolic reprogramming of tomato by AtMYB12 has the potential to improve longitudinal bone growth thus helping in achievement of greater peak bone mass during adolescence. PMID:26917158

  12. Efficient and Selective Enrichment of Ultratrace Cytokinins in Plant Samples by Magnetic Perhydroxy-Cucurbit[8]uril Microspheres.

    PubMed

    Zhang, Qianchun; Li, Gongke; Xiao, Xiaohua; Zhan, Song; Cao, Yujuan

    2016-04-01

    Cytokinins play a critical role in controlling plant growth and development, but it is difficult to be determined in plant samples due to the extremely low concentration level of picomole/gram. So it is important for efficient sample preparation with selective enrichment and rapid separation for accurate analysis of cytokinins. Herein, a supramolecular perhydroxy-cucurbit[8]uril (PCB[8]) was fabricated into the Fe3O4 magnetic particles via chemical bonding assembly and magnetic perhydroxy-cucurbit[8]uril (MPC) materials were obtained. The MPC had good enrichment capability to cytokinins and the enrichment factors were more than 208. The interaction of MPC and cytokinins was investigated by adsorption test and density functional theory (DFT) calculation, the results showed that the main drive forces were the host-guest interaction and hydrogen-bonding interaction between the perhydroxy-cucurbit[8]uril with analytes. Combined with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), the MPC was used as a sorbent of magnetic solid-phase extraction for the analysis of cytokinins in plant samples. A sensitive and selective UPLC-MS/MS method was developed with low detection limits of 0.14-0.32 ng/L for cytokinins analysis. Five cytokinins including zeatin riboside, meta-topolin, kinetin, kinetin riboside, and zip with 6.12-87.3 ng/kg were determined in the soybean sprout and Arabidopsis thaliana. The recoveries were in the range of 76.2-110% with relative standard deviations (n = 5) of 2.3-9.7%. On the basis of these results, magnetic perhydroxy-cucurbit[8]uril materials with selective enrichment capability have good potential on the analysis of ultratrace targets from complicated sample matrixes. PMID:26977773

  13. Selectivity Across the Interface: A Test of Surface Activity in the Composition of Organic-Enriched Aerosols from Bubble Bursting.

    PubMed

    Cochran, Richard E; Jayarathne, Thilina; Stone, Elizabeth A; Grassian, Vicki H

    2016-05-01

    Although theories have been developed that describe surface activity of organic molecules at the air-water interface, few studies have tested how surface activity impacts the selective transfer of molecules from solution phase into the aerosol phase during bubble bursting. The selective transfer of a series of organic compounds that differ in their solubility and surface activity from solution into the aerosol phase is quantified experimentally for the first time. Aerosol was produced from solutions containing salts and a series of linear carboxlyates (LCs) and dicarboxylates (LDCs) using a bubble bursting process. Surface activity of these molecules dominated the transport across the interface, with enrichment factors of the more surface-active C4-C8 LCs (55 ± 8) being greater than those of C4-C8 LDCs (5 ± 1). Trends in the estimated surface concentrations of LCs at the liquid-air interface agreed well with their relative concentrations in the aerosol phase. In addition, enrichment of LCs was followed by enrichment of calcium with respect to other inorganic cations and depletion of chloride and sulfate. PMID:27093579

  14. Increased Oxidative Stress as a Selective Anticancer Therapy

    PubMed Central

    Liu, Jiahui; Wang, Zhichong

    2015-01-01

    Reactive oxygen species (ROS) are closely related to tumorgenesis. Under hypoxic environment, increased levels of ROS induce the expression of hypoxia inducible factors (HIFs) in cancer stem cells (CSCs), resulting in the promotion of the upregulation of CSC markers, and the reduction of intracellular ROS level, thus facilitating CSCs survival and proliferation. Although the ROS level is regulated by powerful antioxidant defense mechanisms in cancer cells, it is observed to remain higher than that in normal cells. Cancer cells may be more sensitive than normal cells to the accumulation of ROS; consequently, it is supposed that increased oxidative stress by exogenous ROS generation therapy has an effect on selectively killing cancer cells without affecting normal cells. This paper reviews the mechanisms of redox regulation in CSCs and the pivotal role of ROS in anticancer treatment. PMID:26273420

  15. Selecting iodine-enriched vegetables and the residual effect of iodate application to soil.

    PubMed

    Dai, Jiu-Lan; Zhu, Yong-Guan; Zhang, Min; Huang, Yi-Zhong

    2004-12-01

    A greenhouse pot experiment was conducted to select vegetables for iodine uptake. The residual effect of iodate fertilization on the growth of and iodine uptake by spinach plants were also investigated. Six vegetables, including leafy vegetables (pakchoi [Brassica chinensis L.], spinach [Spinacia oleracea L.]), tuber vegetables (onion [Allium cepa L.]), shoot vegetables (water spinach [Ipomoea aquatica Forsk.], celery [Apium graveolens L.]), and root vegetables (carrot [Daucus carota var. sativa DC.]) were examined. Results showed that the concentrations of iodate in soil had significant effect on the biomass of edible parts of pakchoi and spinach (p<0.01), whereas the concentrations of iodate in soil had no significant effect on that of carrots, water spinach, celery, and onion. Iodine concentrations in edible parts of vegetables and the transfer factors (TFedible parts) of soil-to-edible parts of vegetables significantly increased with increasing iodine concentrations in soil (p<0.001), and iodine concentrations in edible parts and TFedible parts of spinach were much higher than those of other vegetables at any treatment. Both transfer coefficients for edible parts (TCedible parts) and for aerial parts (TCaerial parts) of vegetables changed differently with increasing iodine concentrations in the soil, and TCedible parts and TCaerial parts of spinach were higher than those of other vegetables. Therefore, spinach was considered as an efficient vegetable for iodine biofortification. Further experiment showed that there is considerable residual effect of soil fertilization with iodate. PMID:15564656

  16. Isolation of Shiga Toxin-Producing Escherichia coli from Ground Beef Using Multiple Combinations of Enrichment Broths and Selective Agars.

    PubMed

    Brusa, Victoria; Piñeyro, Pablo E; Galli, Lucía; Linares, Luciano H; Ortega, Emanuel E; Padola, Nora L; Leotta, Gerardo A

    2016-03-01

    Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens, and beef cattle are recognized as the principal reservoir. The aims of this study were (1) to identify the most sensitive combination of selective enrichment broths and agars for STEC isolation in artificially inoculated ground beef samples, and (2) to evaluate the most efficient combination(s) of methods for naturally contaminated ground beef samples. A total of 192 ground beef samples were artificially inoculated with STEC and non-stx bacterial strains. A combination of four enrichment broths and three agars were evaluated for sensitivity, specificity, and positive predictive value for STEC isolation from experimentally inoculated samples. Enrichments with either modified tryptic soy broth (mTSB) containing 8 mg/L novobiocin (mTSB-8) or modified Escherichia coli (mEC) broth followed by isolation in MacConkey agar were the most sensitive combinations for STEC isolation of artificially inoculated samples. Independently, both enrichments media followed by isolation in MacConkey were used to evaluate ground beef samples from 43 retail stores, yielding 65.1% and 58.1% stx-positive samples by RT-PCR, respectively. No difference was observed in the isolate proportions between these two methods (8/25 [32%] and 8/28 [28.6%]). Identical serotypes and stx genotypes were observed in STEC strains isolated from the same samples by either method. In this study, no single enrichment protocol was sufficient to detect all STEC in artificially inoculated samples and had considerable variation in detection ability with naturally contaminated samples. Moreover, none of the single or combinations of multiple isolation agars used were capable of identifying all STEC serogroups in either artificially inoculated or naturally occurring STEC-contaminated ground beef. Therefore, it may be prudent to conclude that there is no single method or combination of isolation methods capable of identifying all STEC serogroups

  17. Facile preparation of mesoporous carbon-silica-coated graphene for the selective enrichment of endogenous peptides.

    PubMed

    Zhang, Quanqing; Zhang, Qinghe; Xiong, Zhichao; Wan, Hao; Chen, Xiaoting; Li, Hongmei; Zou, Hanfa

    2016-01-01

    A sandwich-like composite composed of ordered mesoporous carbon-silica shell-coated graphene (denoted as graphene@mSiO2-C) was prepared by an in-situ carbonation strategy. A mesoporous silica shell was synthesized by a sol-gel method, and cetyltrimethyl ammonium bromide inside the mesopores were in-situ carbonized as a carbon source to obtain a carbon-silica shell. The resulting mesoporous carbon-silica material with a sandwich structure possesses a high surface area (600 m(2) g(-1)), large pore volume (0.587 cm(3) g(-1)), highly ordered mesoporous pore (3 nm), and high carbon content (30%). This material shows not only high hydrophobicity of graphene and mesoporous carbon but also a hydrophilic silica framework that ensures excellent dispersibility in aqueous solution. The material can capture many more peptides from bovine serum albumin tryptic digests than mesoporous silica shell-coated graphene, demonstrating great enrichment efficiency for peptides. Furthermore, the prepared composite was applied to the enrichment of low-abundance endogenous peptides in human serum. Based on Matrix-Assisted Laser Desorption/ Ionization Time of Flight Mass Spectrometry identification, the graphene@mSiO2-C could efficiently size-exclude proteins and enriches the low-abundant peptides on the graphene and mesoporous carbon. And based on the LC-MS/MS results, 892 endogenous peptides were obtained by graphene@mSiO2-C, hinting at its great potential in peptides analysis. PMID:26695263

  18. Canonical analysis for increased classification speed and channel selection

    NASA Technical Reports Server (NTRS)

    Eppler, W.

    1976-01-01

    The quadratic form can be expressed as a monotonically increasing sum of squares when the inverse covariance matrix is represented in canonical form. This formulation has the advantage that, in testing a particular class hypothesis, computations can be discontinued when the partial sum exceeds the smallest value obtained for other classes already tested. A method for channel selection is presented which arranges the original input measurements in that order which minimizes the expected number of computations. The classification algorithm was tested on data from LARS Flight Line C1 and found to reduce the sum-of-products operations by a factor of 6.7 in comparison with the conventional approach. In effect, the accuracy of a twelve-channel classification was achieved using only that CPU time required for a conventional four-channel classification.

  19. Site-Selective Synthesis of (15)N- and (13)C-Enriched Flavin Mononucleotide Coenzyme Isotopologues.

    PubMed

    Neti, Syam Sundar; Poulter, C Dale

    2016-06-17

    Flavin mononucleotide (FMN) is a coenzyme for numerous proteins involved in key cellular and physiological processes. Isotopically labeled flavin is a powerful tool for studying the structure and mechanism of flavoenzyme-catalyzed reactions by a variety of techniques, including NMR, IR, Raman, and mass spectrometry. In this report, we describe the preparation of labeled FMN isotopologues enriched with (15)N and (13)C isotopes at various sites in the pyrazine and pyrimidine rings of the isoalloxazine core of the cofactor from readily available precursors by a five-step chemo-enzymatic synthesis. PMID:27176708

  20. Triclosan Resistome from Metagenome Reveals Diverse Enoyl Acyl Carrier Protein Reductases and Selective Enrichment of Triclosan Resistance Genes.

    PubMed

    Khan, Raees; Kong, Hyun Gi; Jung, Yong-Hoon; Choi, Jinhee; Baek, Kwang-Yeol; Hwang, Eul Chul; Lee, Seon-Woo

    2016-01-01

    Triclosan (TCS) is a widely used antimicrobial agent and TCS resistance is considered to have evolved in diverse organisms with extensive use of TCS, but distribution of TCS resistance has not been well characterized. Functional screening of the soil metagenome in this study has revealed that a variety of target enoyl acyl carrier protein reductases (ENR) homologues are responsible for the majority of TCS resistance. Diverse ENRs similar to 7-α-hydroxysteroid dehydrogenase (7-α-HSDH), FabG, or the unusual YX7K-type ENR conferred extreme tolerance to TCS. The TCS-refractory 7-α HSDH-like ENR and the TCS-resistant YX7K-type ENR seem to be prevalent in human pathogenic bacteria, suggesting that a selective enrichment occurred in pathogenic bacteria in soil. Additionally, resistance to multiple antibiotics was found to be mediated by antibiotic resistance genes that co-localize with TCS resistance determinants. Further comparative analysis of ENRs from 13 different environments has revealed a huge diversity of both prototypic and metagenomic TCS-resistant ENRs, in addition to a selective enrichment of TCS-resistant specific ENRs in presumably TCS-contaminated environments with reduced ENR diversity. Our results suggest that long-term extensive use of TCS can lead to the selective emergence of TCS-resistant bacterial pathogens, possibly with additional resistance to multiple antibiotics, in natural environments. PMID:27577999

  1. Triclosan Resistome from Metagenome Reveals Diverse Enoyl Acyl Carrier Protein Reductases and Selective Enrichment of Triclosan Resistance Genes

    PubMed Central

    Khan, Raees; Kong, Hyun Gi; Jung, Yong-Hoon; Choi, Jinhee; Baek, Kwang-Yeol; Hwang, Eul Chul; Lee, Seon-Woo

    2016-01-01

    Triclosan (TCS) is a widely used antimicrobial agent and TCS resistance is considered to have evolved in diverse organisms with extensive use of TCS, but distribution of TCS resistance has not been well characterized. Functional screening of the soil metagenome in this study has revealed that a variety of target enoyl acyl carrier protein reductases (ENR) homologues are responsible for the majority of TCS resistance. Diverse ENRs similar to 7-α-hydroxysteroid dehydrogenase (7-α-HSDH), FabG, or the unusual YX7K-type ENR conferred extreme tolerance to TCS. The TCS-refractory 7-α HSDH-like ENR and the TCS-resistant YX7K-type ENR seem to be prevalent in human pathogenic bacteria, suggesting that a selective enrichment occurred in pathogenic bacteria in soil. Additionally, resistance to multiple antibiotics was found to be mediated by antibiotic resistance genes that co-localize with TCS resistance determinants. Further comparative analysis of ENRs from 13 different environments has revealed a huge diversity of both prototypic and metagenomic TCS-resistant ENRs, in addition to a selective enrichment of TCS-resistant specific ENRs in presumably TCS-contaminated environments with reduced ENR diversity. Our results suggest that long-term extensive use of TCS can lead to the selective emergence of TCS-resistant bacterial pathogens, possibly with additional resistance to multiple antibiotics, in natural environments. PMID:27577999

  2. Selective Enrichment Establishes a Stable Performing Community for Microbial Electrosynthesis of Acetate from CO₂.

    PubMed

    Patil, Sunil A; Arends, Jan B A; Vanwonterghem, Inka; van Meerbergen, Jarne; Guo, Kun; Tyson, Gene W; Rabaey, Korneel

    2015-07-21

    The advent of renewable energy conversion systems exacerbates the existing issue of intermittent excess power. Microbial electrosynthesis can use this power to capture CO2 and produce multicarbon compounds as a form of energy storage. As catalysts, microbial populations can be used, provided side reactions such as methanogenesis are avoided. Here a simple but effective approach is presented based on enrichment of a robust microbial community via several culture transfers with H2:CO2 conditions. This culture produced acetate at a concentration of 1.29 ± 0.15 g L(-1) (maximum up to 1.5 g L(-1); 25 mM) from CO2 at a fixed current of -5 Am(-2) in fed-batch bioelectrochemical reactors at high N2:CO2 flow rates. Continuous supply of reducing equivalents enabled acetate production at a rate of 19 ± 2 gm(-2)d(-1) (projected cathode area) in several independent experiments. This is a considerably high rate compared with other unmodified carbon-based cathodes. 58 ± 5% of the electrons was recovered in acetate, whereas 30 ± 10% of the electrons was recovered in H2 as a secondary product. The bioproduction was most likely H2 based; however, electrochemical, confocal microscopy, and community analyses of the cathodes suggested the possible involvement of the cathodic biofilm. Together, the enrichment approach and galvanostatic operation enabled instant start-up of the electrosynthesis process and reproducible acetate production profiles. PMID:26079858

  3. Differential Adhesion Selection for Enrichment of Tendon-Derived Progenitor Cells During In Vitro Culture.

    PubMed

    Durgam, Sushmitha; Schuster, Brooke; Cymerman, Anna; Stewart, Allison; Stewart, Matthew

    2016-08-01

    Preplating, a technique used to separate rapidly adherent fibroblasts from the less-adherent progenitor cells, has been used successfully to isolate skeletal muscle-derived stem cells. The objective of this study was to determine if preplating could also be applied to enrich tendon-derived progenitor cells (TDPCs) before monolayer expansion. Cell suspensions obtained by collagenase digestion of equine lateral digital extensor tendon were serially transferred into adherent plates every 12 h for 4 days. TDPC fractions obtained from initial (TPP0), third (TPP3), and seventh (TPP7) preplate were passaged twice and used for subsequent analyses. Growth/proliferation and basal tenogenic gene expression of the three TDPC fractions were largely similar. Preplating and subsequent monolayer expansion did not alter the immunophenotype (CD29(+), CD44(+), CD90(+), and CD45(-)) and trilineage differentiation capacity of TDPC fractions. Overall, TDPCs were robustly osteogenic, but exhibited comparatively weak adipogenic and chondrogenic capacities. These outcomes indicate that preplating does not enrich for tendon-derived progenitors during in vitro culture, and "whole tendon digest"-derived cells are as appropriate for cell-based therapies. PMID:27406327

  4. Bottlenecks and selective sweeps during domestication have increased deleterious genetic variation in dogs.

    PubMed

    Marsden, Clare D; Ortega-Del Vecchyo, Diego; O'Brien, Dennis P; Taylor, Jeremy F; Ramirez, Oscar; Vilà, Carles; Marques-Bonet, Tomas; Schnabel, Robert D; Wayne, Robert K; Lohmueller, Kirk E

    2016-01-01

    Population bottlenecks, inbreeding, and artificial selection can all, in principle, influence levels of deleterious genetic variation. However, the relative importance of each of these effects on genome-wide patterns of deleterious variation remains controversial. Domestic and wild canids offer a powerful system to address the role of these factors in influencing deleterious variation because their history is dominated by known bottlenecks and intense artificial selection. Here, we assess genome-wide patterns of deleterious variation in 90 whole-genome sequences from breed dogs, village dogs, and gray wolves. We find that the ratio of amino acid changing heterozygosity to silent heterozygosity is higher in dogs than in wolves and, on average, dogs have 2-3% higher genetic load than gray wolves. Multiple lines of evidence indicate this pattern is driven by less efficient natural selection due to bottlenecks associated with domestication and breed formation, rather than recent inbreeding. Further, we find regions of the genome implicated in selective sweeps are enriched for amino acid changing variants and Mendelian disease genes. To our knowledge, these results provide the first quantitative estimates of the increased burden of deleterious variants directly associated with domestication and have important implications for selective breeding programs and the conservation of rare and endangered species. Specifically, they highlight the costs associated with selective breeding and question the practice favoring the breeding of individuals that best fit breed standards. Our results also suggest that maintaining a large population size, rather than just avoiding inbreeding, is a critical factor for preventing the accumulation of deleterious variants. PMID:26699508

  5. Bottlenecks and selective sweeps during domestication have increased deleterious genetic variation in dogs

    PubMed Central

    Marsden, Clare D.; Ortega-Del Vecchyo, Diego; O’Brien, Dennis P.; Taylor, Jeremy F.; Ramirez, Oscar; Vilà, Carles; Marques-Bonet, Tomas; Schnabel, Robert D.; Wayne, Robert K.; Lohmueller, Kirk E.

    2016-01-01

    Population bottlenecks, inbreeding, and artificial selection can all, in principle, influence levels of deleterious genetic variation. However, the relative importance of each of these effects on genome-wide patterns of deleterious variation remains controversial. Domestic and wild canids offer a powerful system to address the role of these factors in influencing deleterious variation because their history is dominated by known bottlenecks and intense artificial selection. Here, we assess genome-wide patterns of deleterious variation in 90 whole-genome sequences from breed dogs, village dogs, and gray wolves. We find that the ratio of amino acid changing heterozygosity to silent heterozygosity is higher in dogs than in wolves and, on average, dogs have 2–3% higher genetic load than gray wolves. Multiple lines of evidence indicate this pattern is driven by less efficient natural selection due to bottlenecks associated with domestication and breed formation, rather than recent inbreeding. Further, we find regions of the genome implicated in selective sweeps are enriched for amino acid changing variants and Mendelian disease genes. To our knowledge, these results provide the first quantitative estimates of the increased burden of deleterious variants directly associated with domestication and have important implications for selective breeding programs and the conservation of rare and endangered species. Specifically, they highlight the costs associated with selective breeding and question the practice favoring the breeding of individuals that best fit breed standards. Our results also suggest that maintaining a large population size, rather than just avoiding inbreeding, is a critical factor for preventing the accumulation of deleterious variants. PMID:26699508

  6. Strong Selection Significantly Increases Epistatic Interactions in the Long-Term Evolution of a Protein

    PubMed Central

    Gupta, Aditi; Adami, Christoph

    2016-01-01

    Epistatic interactions between residues determine a protein’s adaptability and shape its evolutionary trajectory. When a protein experiences a changed environment, it is under strong selection to find a peak in the new fitness landscape. It has been shown that strong selection increases epistatic interactions as well as the ruggedness of the fitness landscape, but little is known about how the epistatic interactions change under selection in the long-term evolution of a protein. Here we analyze the evolution of epistasis in the protease of the human immunodeficiency virus type 1 (HIV-1) using protease sequences collected for almost a decade from both treated and untreated patients, to understand how epistasis changes and how those changes impact the long-term evolvability of a protein. We use an information-theoretic proxy for epistasis that quantifies the co-variation between sites, and show that positive information is a necessary (but not sufficient) condition that detects epistasis in most cases. We analyze the “fossils” of the evolutionary trajectories of the protein contained in the sequence data, and show that epistasis continues to enrich under strong selection, but not for proteins whose environment is unchanged. The increase in epistasis compensates for the information loss due to sequence variability brought about by treatment, and facilitates adaptation in the increasingly rugged fitness landscape of treatment. While epistasis is thought to enhance evolvability via valley-crossing early-on in adaptation, it can hinder adaptation later when the landscape has turned rugged. However, we find no evidence that the HIV-1 protease has reached its potential for evolution after 9 years of adapting to a drug environment that itself is constantly changing. We suggest that the mechanism of encoding new information into pairwise interactions is central to protein evolution not just in HIV-1 protease, but for any protein adapting to a changing environment. PMID

  7. Strong Selection Significantly Increases Epistatic Interactions in the Long-Term Evolution of a Protein.

    PubMed

    Gupta, Aditi; Adami, Christoph

    2016-03-01

    Epistatic interactions between residues determine a protein's adaptability and shape its evolutionary trajectory. When a protein experiences a changed environment, it is under strong selection to find a peak in the new fitness landscape. It has been shown that strong selection increases epistatic interactions as well as the ruggedness of the fitness landscape, but little is known about how the epistatic interactions change under selection in the long-term evolution of a protein. Here we analyze the evolution of epistasis in the protease of the human immunodeficiency virus type 1 (HIV-1) using protease sequences collected for almost a decade from both treated and untreated patients, to understand how epistasis changes and how those changes impact the long-term evolvability of a protein. We use an information-theoretic proxy for epistasis that quantifies the co-variation between sites, and show that positive information is a necessary (but not sufficient) condition that detects epistasis in most cases. We analyze the "fossils" of the evolutionary trajectories of the protein contained in the sequence data, and show that epistasis continues to enrich under strong selection, but not for proteins whose environment is unchanged. The increase in epistasis compensates for the information loss due to sequence variability brought about by treatment, and facilitates adaptation in the increasingly rugged fitness landscape of treatment. While epistasis is thought to enhance evolvability via valley-crossing early-on in adaptation, it can hinder adaptation later when the landscape has turned rugged. However, we find no evidence that the HIV-1 protease has reached its potential for evolution after 9 years of adapting to a drug environment that itself is constantly changing. We suggest that the mechanism of encoding new information into pairwise interactions is central to protein evolution not just in HIV-1 protease, but for any protein adapting to a changing environment. PMID

  8. Code RED (Remediation and Enrichment Days): The Complex Journey of a School and University Partnership's Process to Increase Mathematics Achievement

    ERIC Educational Resources Information Center

    Moyer, Patricia S.; Dockery, Kim; Jamieson, Spencer; Ross, Julie

    2007-01-01

    This study examined a focused remediation and enrichment effort among school and university faculty to affect the mathematics achievement of a group of third-grade students in a Title I elementary school. A total of 87 students participated in the Code RED (Remediation and Enrichment Days) Project. During the Code RED Project, student assessment…

  9. Sc3CH@C80: selective 13C enrichment of the central carbon atom†

    PubMed Central

    Junghans, Katrin; Rosenkranz, Marco; Popov, Alexey A.

    2016-01-01

    Sc3CH@C80 is synthesized and characterized by 1H, 13C, and 45Sc NMR. A large negative chemical shift of the proton, −11.73 ppm in the Ih and −8.79 ppm in the D5h C80 cage isomers, is found. 13C satellites in the 1H NMR spectrum enabled indirect determination of the 13C chemical shift for the central carbon at 173 ± 1 ppm. Intensity of the satellites allowed determination of the 13C content for the central carbon atom. This unique possibility is applied to analyze the cluster/cage 13C distribution in mechanistic studies employing either 13CH4 or 13C powder to enrich Sc3CH@C80 with 13C. PMID:27109443

  10. Sc3CH@C80: selective (13)C enrichment of the central carbon atom.

    PubMed

    Junghans, Katrin; Rosenkranz, Marco; Popov, Alexey A

    2016-05-01

    Sc3CH@C80 is synthesized and characterized by (1)H, (13)C, and (45)Sc NMR. A large negative chemical shift of the proton, -11.73 ppm in the Ih and -8.79 ppm in the D5h C80 cage isomers, is found. (13)C satellites in the (1)H NMR spectrum enabled indirect determination of the (13)C chemical shift for the central carbon at 173 ± 1 ppm. Intensity of the satellites allowed determination of the (13)C content for the central carbon atom. This unique possibility is applied to analyze the cluster/cage (13)C distribution in mechanistic studies employing either (13)CH4 or (13)C powder to enrich Sc3CH@C80 with (13)C. PMID:27109443

  11. Selective Enrichment Yields Robust Ethene-Producing Dechlorinating Cultures from Microcosms Stalled at cis-Dichloroethene

    PubMed Central

    Delgado, Anca G.; Kang, Dae-Wook; Nelson, Katherine G.; Fajardo-Williams, Devyn; Miceli, Joseph F.; Done, Hansa Y.; Popat, Sudeep C.; Krajmalnik-Brown, Rosa

    2014-01-01

    Dehalococcoides mccartyi strains are of particular importance for bioremediation due to their unique capability of transforming perchloroethene (PCE) and trichloroethene (TCE) to non-toxic ethene, through the intermediates cis-dichloroethene (cis-DCE) and vinyl chloride (VC). Despite the widespread environmental distribution of Dehalococcoides, biostimulation sometimes fails to promote dechlorination beyond cis-DCE. In our study, microcosms established with garden soil and mangrove sediment also stalled at cis-DCE, albeit Dehalococcoides mccartyi containing the reductive dehalogenase genes tceA, vcrA and bvcA were detected in the soil/sediment inocula. Reductive dechlorination was not promoted beyond cis-DCE, even after multiple biostimulation events with fermentable substrates and a lengthy incubation. However, transfers from microcosms stalled at cis-DCE yielded dechlorination to ethene with subsequent enrichment cultures containing up to 109 Dehalococcoides mccartyi cells mL−1. Proteobacterial classes which dominated the soil/sediment communities became undetectable in the enrichments, and methanogenic activity drastically decreased after the transfers. We hypothesized that biostimulation of Dehalococcoides in the cis-DCE-stalled microcosms was impeded by other microbes present at higher abundances than Dehalococcoides and utilizing terminal electron acceptors from the soil/sediment, hence, outcompeting Dehalococcoides for H2. In support of this hypothesis, we show that garden soil and mangrove sediment microcosms bioaugmented with their respective cultures containing Dehalococcoides in high abundance were able to compete for H2 for reductive dechlorination from one biostimulation event and produced ethene with no obvious stall. Overall, our results provide an alternate explanation to consolidate conflicting observations on the ubiquity of Dehalococcoides mccartyi and occasional stalling of dechlorination at cis-DCE; thus, bringing a new perspective to better

  12. Carbon-Decorated TiO2 Nanotube Membranes: A Renewable Nanofilter for Charge-Selective Enrichment of Proteins.

    PubMed

    Xu, Jingwen; Yang, Lingling; Han, Yuyao; Wang, Yongmei; Zhou, Xuemei; Gao, Zhida; Song, Yan-Yan; Schmuki, Patrik

    2016-08-31

    In this work, we design a TiO2 nanomembrane (TiNM) that can be used as a nanofilter platform for selective enrichment of specific proteins. After a first use, the photocatalytic properties of TiO2 allow the decomposition of unwanted remnants on the substrate and thus make the platform reusable. To construct this platform, we fabricate a free-standing TiO2 nanotube array and remove the bottom oxide to form a both-end-open TiNM. By pyrolysis of the natural tube wall contamination, the walls become decorated with graphitic carbon patches (C/TiNM). Owing to the large surface area, the amphiphilic nature and the charge-adjustable character, this C/TiNM can be used to extract and enrich hydrophobic charged biomolecules. Using human serum albumin (HSA) as a model protein as well as protein mixtures, we show that the composite membrane exhibits a highly enhanced loading capacity and protein selectivity and is reusable after a short UV treatment. PMID:27509326

  13. Selective enrichment of electrogenic bacteria for fuel cell application: Enumerating microbial dynamics using MiSeq platform.

    PubMed

    Vamshi Krishna, K; Venkata Mohan, S

    2016-08-01

    This study is intended to examine the effect of pretreatment on selective enrichment of electrogenic bacteria from mixed culture. It has been observed that the iodopropane and heat-shock pretreatments suppress the growth of non-exoelectrons, while selecting only a limited number of strains belonging to genera Xanthomonas, Pseudomonas and Prevotella while untreated control inoculum showed more diverse community comprising of both exoelectrogens and non-exoelectrogens. High power output was observed in iodopropane (180mW/m(2)) pretreated microbial fuel cell (MFC) compared to heat-shock pretreated MFC (128mW/m(2)) and untreated control (92mW/m(2)). Coulombic efficiency of iodopropane and heat-shock pretreated MFC was higher compared to untreated control MFC, while drop in pH and volatile fatty acids (VFA) production was less in iodopropane pretreated MFC signifying the shifts in bacterial community structure toward electrogenesis instead of fermentation. These results signify the role of iodopropane and heat pretreatments on enrichment of electrogenic bacteria for fuel cell application. PMID:27061058

  14. GABA selectively increases mucin-1 expression in isolated pig jejunum.

    PubMed

    Braun, Hannah-Sophie; Sponder, Gerhard; Pieper, Robert; Aschenbach, Jörg R; Deiner, Carolin

    2015-11-01

    The inhibitory neurotransmitter GABA (γ-aminobutyric acid) is synthesized by glutamic acid decarboxylase, which is expressed in the central nervous system and in various other tissues including the intestine. Moreover, GABA can be ingested in vegetarian diets or produced by bacterial commensals in the gastrointestinal tract. As previous studies in lung have suggested a link between locally increased GABA availability and mucin 5AC production, the present study sought to test whether the presence or lack of GABA (and its precursor glutamine) has an effect on intestinal mucin expression. Porcine jejunum epithelial preparations were incubated with two different amounts of GABA or glutamine on the mucosal side for 4 h, and changes in the relative gene expression of seven different mucins, enzymes involved in mucin shedding, GABA B receptor, enzymes involved in glutamine/GABA metabolism, glutathione peroxidase 2, and interleukin 10 were examined by quantitative PCR (TaqMan(®) assays). Protein expression of mucin-1 (MUC1) was analyzed by Western blot. On the RNA level, only MUC1 was significantly up-regulated by both GABA concentrations compared with the control. Glutamine-treated groups showed the same trend. On the protein level, all treatment groups showed a significantly higher MUC1 expression than the control group. We conclude that GABA selectively increases the expression of MUC1, a cell surface mucin that prevents the adhesion of microorganisms, because of its size and negative charge, and therefore propose that the well-described positive effects of glutamine on enterocytes and intestinal integrity are partly attributable to effects of its metabolite GABA. PMID:26471792

  15. Designed synthesis of aptamer-immobilized magnetic mesoporous silica/Au nanocomposites for highly selective enrichment and detection of insulin.

    PubMed

    Xiong, Ya; Deng, Chunhui; Zhang, Xiangmin; Yang, Pengyuan

    2015-04-29

    We designed and synthesized aptamer-immobilized magnetic mesoporous silica/Au nanocomposites (MMANs) for highly selective detection of unlabeled insulin in complex biological media using MALDI-TOF MS. The aptamer was easily anchored onto the gold nanoparticles in the mesochannels of MMANs with high capacity for highly efficient and specific enrichment of insulin. With the benefit from the size-exclusion effect of the mesoporous silica shell with a narrow pore size distribution (∼2.9 nm), insulin could be selectively detected despite interference from seven untargeted proteins with different size dimensions. This method exhibited an excellent response for insulin in the range 2-1000 ng mL(-1). Moreover, good recoveries in the detection of insulin in 20-fold diluted human serum were achieved. We anticipate that this novel method could be extended to other biomarkers of interest and potentially applied in disease diagnostics. PMID:25854412

  16. Plasma cholesterol-lowering activity of gingerol- and shogaol-enriched extract is mediated by increasing sterol excretion.

    PubMed

    Lei, Lin; Liu, Yuwei; Wang, Xiaobo; Jiao, Rui; Ma, Ka Ying; Li, Yuk Man; Wang, Lijun; Man, Sun Wa; Sang, Shengmin; Huang, Yu; Chen, Zhen-Yu

    2014-10-29

    The present study investigated the cholesterol-lowering activity of gingerol- and shogaol-enriched ginger extract (GSE). Thirty hamsters were divided into three groups and fed the control diet or one of the two experimental diets containing 0.5 and 1.0% GSE. Plasma total cholesterol, liver cholesterol, and aorta atherosclerotic plaque were dose-dependently decreased with increasing amounts of GSE added into diets. The fecal sterol analysis showed dietary GSE increased the excretion of both neutral and acidic sterols in a dose-dependent manner. GSE down-regulated the mRNA levels of intestinal Niemann-Pick C1-like 1 protein (NPC1L1), acyl CoA:cholesterol acyltransferase 2 (ACAT2), microsomal triacylglycerol transport protein (MTP), and ATP binding cassette transporter 5 (ABCG5), whereas it up-regulated hepatic cholesterol-7α-hydroxylase (CYP7A1). It was concluded that beneficial modification of the lipoprotein profile by dietary GSE was mediated by enhancing excretion of fecal cholesterol and bile acids via up-regulation of hepatic CYP7A1 and down-regulation of mRNA of intestinal NPC1L1, ACAT2, and MTP. PMID:25290252

  17. Increasing long term response by selecting for favorable minor alleles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Long-term response of genomic selection can be improved by considering allele frequencies of selected markers or quantitative trait loci (QTLs). A previous formula to weight allele frequency of favorable minor alleles was tested, and 2 new formulas were developed. The previous formula used nonlinear...

  18. Increasing Verbal Behavior of a Student Who Is Selectively Mute

    ERIC Educational Resources Information Center

    Beare, Paul; Torgerson, Colleen; Creviston, Cindy

    2008-01-01

    "Selective mutism" is the term used to describe a disorder in which a person speaks only in restricted stimulus situations. Examination of single-subject research concerning selective mutism reveals the most popular and successful interventions to instate speech involve a combination of behavior modification procedures. The present research…

  19. Bit selection increases coiled tubing and slimhole success

    SciTech Connect

    Feiner, R.F.

    1995-07-01

    Slimhole applications have grown within the past few years to include deepening existing wells to untapped reservoirs, drilling smaller well programs to reduce tangible costs and recompleting wells to adjacent reservoirs through directional or horizontal sidetracks. When selecting the proper bit for an interval, the ultimate goal is the same in the slimhole application as in the conventional application -- to save the operator money by reducing drilling cost per foot (CPF). Slimhole bit selection is a three-step process: (1) identify the characteristics of the formations to be drilled; (2) analyze the operational limitations of the slimhole application; and (3) select the bit type that will most economically drill the interval. Knowledge of lithology is crucial to the selection process. Accurate formation knowledge can be acquired from offset well records, mud logs, cores, electric logs, compressive rock strength analysis and any other information relevant to the drilling operation. This paper reviews the steps in selecting slimhole bits and completion equipment.

  20. Selective enrichment and characterization of a phosphorus-removing bacterial consortium from activated sludge.

    PubMed

    Hollender, J; Dreyer, U; Kornberger, L; Kämpfer, P; Dott, W

    2002-01-01

    Under alternating aerobic/anaerobic conditions and without additional carbon sources, a bacterial consortium consisting initially of 18 bacterial strains was obtained in a sequence batch reactor. The phosphorus removal capability could only be maintained using sterile filtrate of activated sludge as medium. The addition of calcium and magnesium salts, as well as vitamins and trace elements, to autoclaved sterile filtrate of activated sludge was not sufficient to achieve stable phosphorus removal. A further enrichment by subcultivation on solid, agar, freezing, and shortening of the aerobic and anaerobic phases led to a defined bacterial consortium consisting of four strains. On the basis of physiological and chemotaxonomic characterization, and partial 16S rRNA sequencing, one of the organisms was identified as Delftia acidovorans. A further isolate belonged to the Bacillus cereus group, and the third isolate was identified as Microbacterium sp.. The remaining strain seems to represent a new genus within the Flavobacteriaceae. Under continuous chemostat conditions, this consortium was able to remove up to 9.6 mg P/l phosphate in the aerobic phase and released up to 8.5 mg/l in the anaerobic phase. Up to 25 mg P-polyphosphate/g dry mass was stored under aerobic conditions. PMID:11831470

  1. Selenium-Enriched Foods Are More Effective at Increasing Glutathione Peroxidase (GPx) Activity Compared with Selenomethionine: A Meta-Analysis

    PubMed Central

    Bermingham, Emma N.; Hesketh, John E.; Sinclair, Bruce R.; Koolaard, John P.; Roy, Nicole C.

    2014-01-01

    Selenium may play a beneficial role in multi-factorial illnesses with genetic and environmental linkages via epigenetic regulation in part via glutathione peroxidase (GPx) activity. A meta-analysis was undertaken to quantify the effects of dietary selenium supplementation on the activity of overall GPx activity in different tissues and animal species and to compare the effectiveness of different forms of dietary selenium. GPx activity response was affected by both the dose and form of selenium (p < 0.001). There were differences between tissues on the effects of selenium supplementation on GPx activity (p < 0.001); however, there was no evidence in the data of differences between animal species (p = 0.95). The interactions between dose and tissue, animal species and form were significant (p < 0.001). Tissues particularly sensitive to changes in selenium supply include red blood cells, kidney and muscle. The meta-analysis identified that for animal species selenium-enriched foods were more effective than selenomethionine at increasing GPx activity. PMID:25268836

  2. Niche Mimicking for Selection and Enrichment of Liver Cancer Stem Cells by Hyaluronic Acid-Based Multilayer Films.

    PubMed

    Lee, I-Chi; Chuang, Chun-Chieh; Wu, Yu-Chieh

    2015-10-14

    Cancer stem cells (CSCs) represent a subpopulation of tumor cells that exhibit capacities for self-renewal, tumor initiation, disease relapse or metastasis, and resistance to chemotherapy and radiotherapy. However, the major obstacle associated with the use of CSCs is the difficulty in their isolation and enrichment. According to recent studies, CSCs share similar properties with normal stem cells, and it has been observed that hyaluronan (HA) plays a key factor in CSCs niches and that HA-mediated CD44 interaction promotes tumor progression. Therefore, HA-based multilayer films were used to fabricate sequential surface properties variation and to mimic CSC niches. A quartz crystal microbalance was used to investigate the layer-by-layer adsorption of PAH/HA multilayer films. Colony formation was observed on a series of poly(allylamine hydrochloride) PAH/HA multilayer films, and cytotoxicity and cell viability were evaluated by MTT, LDH and live/dead assay. It was observed that the cells isolated from (PAH/HA)3 displayed the best colony formation ability and that the expression of CD133/CD44 double positive cells was up-regulated to approximately 70% after 7 days of culture. Furthermore, the cells isolated from (PAH/HA)3 displayed higher chemo-resistance than the control group. The stem-cell-related genes expression of selected cells from (PAH/HA)3 after 7 days of culture was significantly different from that of the control group. In conclusion, this study provides a label-free selection and enrichment system that could serve as a new strategy for the future development of CSC selection and drug evaluation in cancer therapy. PMID:26379083

  3. Magnetic immunoaffinity enrichment for selective capture and MS/MS analysis of N-terminal-TMPP-labeled peptides.

    PubMed

    Bland, Céline; Bellanger, Laurent; Armengaud, Jean

    2014-02-01

    Proteogenomics is the alliance of proteomics and genomics with the aim of better annotating structural genes based on experimental, protein-based data items established by tandem mass spectrometry. While, on average, more than one-tenth of protein N-termini are incorrectly annotated, there is a crucial need for methodological approaches to systematically establish the translational starts of polypeptides, and their maturations, such as N-terminal methionine processing and peptide signal excision. Refinement of genome annotation through correction of wrongly annotation initiation start site and detection of unannotated genes can be achieved after enrichment and detection of protein N-termini by mass spectrometry. Here we describe a straightforward strategy to specifically label protein N-termini with a positively charged TMPP label to selectively capture these entities with in-house-developed anti-TMPP antibodies coupled to magnetic beads and to analyze them by nanoLC-MS/MS. While most N-terminomics-oriented approaches are based on the depletion of internal peptides to retrieve N-terminal peptides, this enrichment approach is fast and the results are highly specific for improved, ionizable, TMPP-labeled peptides. The whole proteome of the model marine bacterium, Roseobacter denitrificans, was analyzed, leading to the identification of more than twice the number of N-terminal peptides compared with the nonenriched fraction. A total of 269 proteins were characterized in terms of their N-termini. In addition, three unannotated genes were identified based on multiple, redundant N-terminal peptides. Our strategy greatly simplifies the systematic and automatic proteogenomic annotation of genomes as well as degradomics-oriented approaches, focusing the mass spectrometric efforts on the most crucial enriched fractions. PMID:24313271

  4. Select microtubule inhibitors increase lysosome acidity and promote lysosomal disruption in acute myeloid leukemia (AML) cells.

    PubMed

    Bernard, Dannie; Gebbia, Marinella; Prabha, Swayam; Gronda, Marcela; MacLean, Neil; Wang, Xiaoming; Hurren, Rose; Sukhai, Mahadeo A; Cho, Eunice E; Manolson, Morris F; Datti, Alessandro; Wrana, Jeffrey; Minden, Mark D; Al-Awar, Rima; Aman, Ahmed; Nislow, Corey; Giaever, Guri; Schimmer, Aaron D

    2015-07-01

    To identify new biological vulnerabilities in acute myeloid leukemia, we screened a library of natural products for compounds cytotoxic to TEX leukemia cells. This screen identified the novel small molecule Deoxysappanone B 7,4' dimethyl ether (Deox B 7,4), which possessed nanomolar anti-leukemic activity. To determine the anti-leukemic mechanism of action of Deox B 7,4, we conducted a genome-wide screen in Saccharomyces cerevisiae and identified enrichment of genes related to mitotic cell cycle as well as vacuolar acidification, therefore pointing to microtubules and vacuolar (V)-ATPase as potential drug targets. Further investigations into the mechanisms of action of Deox B 7,4 and a related analogue revealed that these compounds were reversible microtubule inhibitors that bound near the colchicine site. In addition, Deox B 7,4 and its analogue increased lysosomal V-ATPase activity and lysosome acidity. The effects on microtubules and lysosomes were functionally important for the anti-leukemic effects of these drugs. The lysosomal effects were characteristic of select microtubule inhibitors as only the Deox compounds and nocodazole, but not colchicine, vinca alkaloids or paclitaxel, altered lysosome acidity and induced lysosomal disruption. Thus, our data highlight a new mechanism of action of select microtubule inhibitors on lysosomal function. PMID:25832785

  5. Design and synthesis of magnetic binary metal oxides nanocomposites through dopamine chemistry for highly selective enrichment of phosphopeptides.

    PubMed

    Wang, Mengyi; Sun, Xueni; Li, Yan; Deng, Chunhui

    2016-03-01

    In this work, for the first time, magnetic binary metal oxides nanocomposites which integrated Zr and Ti into one entity on an atomic scale on polydopamine coated magnetic graphene (magG/PD/(Zr-Ti)O4 ) was designed and synthesized, and applied to the enrichment of phosphopeptides. The newly prepared magG/PD/(Zr-Ti)O4 composites gathered the advantages of large surface area, superparamagnetism, biocompatibility and the enhanced affinity properties to phosphopeptides. MagG/PD/ZrO2 , magG/PD/TiO2 , as well as the simple physical mixture of them were introduced to compare with magG/PD/(Zr-Ti)O4 composites. High sensitivity (1 pg/μL or 4.0 × 10(-11) M) and selectivity (weight ratio of β-casein and BSA reached up to 1:8000) toward phosphopeptides were also presented for magG/PD/(Zr-Ti)O4 composites. Additionally, mouse brain tissue was chose as the real samples to further investigate the phosphopeptides enrichment ability of this new material. PMID:26702589

  6. Selective Enrichment with a Resuscitation Step for Isolation of Freeze-Injured Escherichia coli O157:H7 from Foods

    PubMed Central

    Hara-Kudo, Y.; Ikedo, M.; Kodaka, H.; Nakagawa, H.; Goto, K.; Masuda, T.; Konuma, H.; Kojima, T.; Kumagai, S.

    2000-01-01

    We studied injury of Escherichia coli O157:H7 cells in 11 food items during freeze storage and methods of isolating freeze-injured E. coli O157:H7 cells from foods. Food samples inoculated with E. coli O157:H7 were stored for 16 weeks at −20°C in a freezer. Noninjured and injured cells were counted by using tryptic soy agar and sorbitol MacConkey agar supplemented with cefixime and potassium tellurite. Large populations of E. coli O157:H7 cells were injured in salted cabbage, grated radish, seaweed, and tomato samples. In an experiment to detect E. coli O157:H7 in food samples artificially contaminated with freeze-injured E. coli O157:H7 cells, the organism was recovered most efficiently after the samples were incubated in modified E. coli broth without bile salts at 25°C for 2 h and then selectively enriched at 42°C for 18 h by adding bile salts and novobiocin. Our enrichment method was further evaluated by isolating E. coli O157:H7 from frozen foods inoculated with the organism prior to freezing. Two hours of resuscitation at 25°C in nonselective broth improved recovery of E. coli O157:H7 from frozen grated radishes and strawberries, demonstrating that the resuscitation step is very effective for isolating E. coli O157:H7 from frozen foods contaminated with injured E. coli O157:H7 cells. PMID:10877780

  7. Towards the selection of a produced water enrichment for biological gas hydrate inhibitors.

    PubMed

    Wilson, Sandra L; Voordouw, Gerrit; Walker, Virginia K

    2014-09-01

    Economic concerns associated with the recovery of non-conventional hydrocarbon reserves include unexpected ice as well as ice-like gas hydrate formation. Antifreeze proteins (AFPs) inhibit ice growth, and experiments with fish, plant, and insect AFPs have shown promise of effective gas hydrate inhibition in lab-scale experiments. If produced on an industrial scale, AFPs could provide a more environmentally friendly alternative to kinetic inhibitors, but a large-scale production of these AFPs is not currently feasible. We believe that these difficulties could be surmounted by the production of microbial AFPs, but to date, only a few such proteins have been identified and purified, and none of these are associated with hydrocarbon reserves. Here, we have used ice-affinity and freeze-thaw stress to select microbes derived from oil and gas formation water, or produced water, as a source of anaerobic microbial communities. Ice-affinity successfully incorporated anaerobic bacteria under aerobic conditions, and the mixed culture had ice-associating properties. Under these conditions, ice-affinity selection does not result in cultivatable isolates, but similar, cultivable microbes were obtained following freeze-thaw selection under anaerobic conditions. Since these mixed cultures inhibited the growth of ice crystals, they also have the potential to inhibit hydrate growth. Overall, freeze-thaw selection provides a promising first step towards the isolation of microbes capable of the inhibition of ice and gas hydrate growth, for possible application for energy exploration and recovery at high-latitudes and in-deep, cold waters. PMID:24819435

  8. Targeted toxin-based selectable drug-free enrichment of Mammalian cells with high transgene expression.

    PubMed

    Sato, Masahiro; Akasaka, Eri; Saitoh, Issei; Ohtsuka, Masato; Nakamura, Shingo; Sakurai, Takayuki; Watanabe, Satoshi

    2013-01-01

    Almost all transfection protocols for mammalian cells use a drug resistance gene for the selection of transfected cells. However, it always requires the characterization of each isolated clone regarding transgene expression, which is time-consuming and labor-intensive. In the current study, we developed a novel method to selectively isolate clones with high transgene expression without drug selection. Porcine embryonic fibroblasts were transfected with pCEIEnd, an expression vector that simultaneously expresses enhanced green fluorescent protein (EGFP) and endo-b-galactosidase C(EndoGalC; an enzyme capable of digesting cell surface a-Gal epitope) upon transfection. After transfection, the surviving cells were briefly treated with IB4SAP (a-Gal epitope-specific BS-I-B4 lectin conjugated with a toxin saporin). The treated cells were then allowed to grow in normal medium, during which only cells strongly expressing EndoGalC and EGFP would survive because of the absence of a-Gal epitopes on their cell surface. Almost all the surviving colonies after IB4SAP treatment were in fact negative for BS-I-B4 staining, and also strongly expressed EGFP. This system would be particularly valuable for researchers who wish to perform large-scale production of therapeutically important recombinant proteins. PMID:24832665

  9. Graphene-Templated Synthesis of Magnetic Metal Organic Framework Nanocomposites for Selective Enrichment of Biomolecules.

    PubMed

    Cheng, Gong; Wang, Zhi-Gang; Denagamage, Sachira; Zheng, Si-Yang

    2016-04-27

    Successful control of homogeneous and complete coating of graphene or graphene-based composites with well-defined metal organic framework (MOF) layers is a great challenge. Herein, novel magnetic graphene MOF composites were constructed via a simple strategy for self-assembly of well-distributed, dense, and highly porous MOFs on both sides of graphene nanosheets. Graphene functionalized with magnetic nanoparticles and carboxylic groups on both sides was explored as the backbone and template to direct the controllable self-assembly of MOFs. The prepared composite materials have a relatively high specific surface area (345.4 m(2) g(-1)), and their average pore size is measured to be 3.2 nm. Their relatively high saturation magnetization (23.8 emu g(-1)) indicates their strong magnetism at room temperature. Moreover, the multifunctional composite was demonstrated to be a highly effective affinity material in selective extraction and separation of low-concentration biomolecules from biological samples, in virtue of the size-selection property of the unique porous structure and the excellent affinity of the composite materials. Besides providing a solution for the construction of well-defined functional graphene-based MOFs, this work could also contribute to selective extraction of biomolecules, in virtue of the universal affinity between immobilized metal ions and biomolecules. PMID:27046460

  10. Thiol-ene click synthesis of L-Cysteine-bonded zwitterionic hydrophilic magnetic nanoparticles for selective and efficient enrichment of glycopeptides.

    PubMed

    Wu, Runqing; Xie, Yang; Deng, Chunhui

    2016-11-01

    Efficient and specific enrichment of low-abundant glycopeptides from complex biological samples is essential to glycoproteomics analysis. Herein, novel magnetic zwitterionic hydrophilic nanoparticles based on thiol-ene click chemistry were synthesized. The functionalized magnetic nanoparticles exhibited superior performance in glycopeptide enrichment of HRP tryptic digest, demonstrating low detection limit (0.04ng/μL), high selectivity (a mixture of HRP and BSA at the mass ratio of 1:50) and reproducibility (5 repeating cycles). In addition, the material was successfully applied to glycopeptide enrichment from human serum. The outstanding results indicate the potential of the method in the development of glycoproteomics analysis in real biological samples. PMID:27591639

  11. Multiple trait genomic selection methods increase genetic value prediction accuracy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomic selection predicts genetic values with genome-wide markers. It is rapidly emerging in plant breeding and is widely implemented in animal breeding. Genetic correlations between quantitative traits are pervasive in many breeding programs. These correlations indicate that measurements of one tr...

  12. Knowledge Driven Variable Selection (KDVS) – a new approach to enrichment analysis of gene signatures obtained from high–throughput data

    PubMed Central

    2013-01-01

    Background High–throughput (HT) technologies provide huge amount of gene expression data that can be used to identify biomarkers useful in the clinical practice. The most frequently used approaches first select a set of genes (i.e. gene signature) able to characterize differences between two or more phenotypical conditions, and then provide a functional assessment of the selected genes with an a posteriori enrichment analysis, based on biological knowledge. However, this approach comes with some drawbacks. First, gene selection procedure often requires tunable parameters that affect the outcome, typically producing many false hits. Second, a posteriori enrichment analysis is based on mapping between biological concepts and gene expression measurements, which is hard to compute because of constant changes in biological knowledge and genome analysis. Third, such mapping is typically used in the assessment of the coverage of gene signature by biological concepts, that is either score–based or requires tunable parameters as well, limiting its power. Results We present Knowledge Driven Variable Selection (KDVS), a framework that uses a priori biological knowledge in HT data analysis. The expression data matrix is transformed, according to prior knowledge, into smaller matrices, easier to analyze and to interpret from both computational and biological viewpoints. Therefore KDVS, unlike most approaches, does not exclude a priori any function or process potentially relevant for the biological question under investigation. Differently from the standard approach where gene selection and functional assessment are applied independently, KDVS embeds these two steps into a unified statistical framework, decreasing the variability derived from the threshold–dependent selection, the mapping to the biological concepts, and the signature coverage. We present three case studies to assess the usefulness of the method. Conclusions We showed that KDVS not only enables the

  13. Effect of selectively intercalated polyiodide on the electric transports of metallic- and semiconducting-enriched single-wall carbon nanotube networks

    NASA Astrophysics Data System (ADS)

    Fujimori, Toshihiko; Urita, Koki

    2016-06-01

    We report the selective intercalation of polyiodide chains (I5-) inside the interstitial sites of single-wall carbon nanotube (SWCNT) bundles of which internal sites are pre-encapsulated with monatomic sulfur chains. By using metallic- and semiconducting-enriched SWCNTs with diameter of ˜1 nm, our direct-current electric transport measurements reveal that the I5- intercalation on the metallic- and semiconducting-enriched SWCNT networks exhibits an opposite trend on the temperature dependence of the electric resistance at cryogenic temperature. Based on our analysis using the fluctuation-induced tunneling conduction model, the intercalation of I5- chains into the semiconducting-SWCNTs leads to the increase in energy barriers required for tunneling processes. Since the charge transfer is negligible between I5- chains and the semiconducting-SWCNTs, the main effect of the intercalated I5- on the semiconducting-SWCNTs is to behave as a scattering center below 50 K. In contrast to the semiconducting-SWCNTs, the intercalation of I5- chains into the metallic-SWCNTs results in the suppression of tunneling barriers due to the charge transfer interaction. The energy barrier is further reduced by the encapsulation of I5- chains inside the metallic-SWCNT, implying that the doping effect could be more effectively enhanced by the interaction through the inner spaces of SWCNTs.

  14. Evaluation of corn oil as an additive in the pre-enrichment step to increase recovery of Salmonella enterica from oregano.

    PubMed

    Jean-Gilles Beaubrun, Junia; Flamer, Marie-Laure; Addy, Nicole; Ewing, Laura; Gopinath, Gopal; Jarvis, Karen; Grim, Chris; Hanes, Darcy E

    2016-08-01

    Phenolic compounds associated with essential oils of spices and herbs possess a variety of antioxidant and antimicrobial properties that interfere with Salmonella detection from fresh and dried products. Finding a compound to neutralize the effect of these antimicrobial compounds, while allowing Salmonella growth during pre-enrichment, is a crucial step in both traditional pathogen isolation and molecular detection from these foods. This study evaluated the effectiveness of corn oil as a component of the pre-enrichment broth to counteract antimicrobial compounds properties and increase the recovery of Salmonella from spices. Oregano samples artificially contaminated with Salmonella enterica were pre-enriched in modified Buffered Peptone Water (mBPW) supplemented with and without 2% (vol/vol) corn oil respectively. Samples were incubated overnight at 37 °C. The results showed that recovery of Salmonella from oregano samples was increased by ≥50% when pre-enriched with corn oil. Serovars were confirmed using a PCR serotyping method. In addition, shot-gun metagenomics analyses demonstrated bacterial diversity and the effect of corn oil on the relative prevalence of Salmonella in the oregano samples. Modifying pre-enrichment broths with corn oil improved the detection and isolation of Salmonella from oregano, and may provide an alternative method for pathogen detection in dried food matrices such as spices. PMID:27052719

  15. Highly selective and sensitive enrichment of phosphopeptides via NiO nanoparticles using a microwave-assisted centrifugation on-particle ionization/enrichment approach in MALDI-MS.

    PubMed

    Hasan, Nazim; Wu, Hui-Fen

    2011-07-01

    The strategy to concentrate phosphopeptides has become a critical issue for mapping protein phosphorylation sites, which are well known as posttranslational modifications in proteomics. In this study, we propose a simple and highly sensitive method for phosphopeptide enrichment on NiO nanoparticles (NPs) from a trypsin predigested phosphoprotein complex solution in a microwave oven. Furthermore, this technique was combined with centrifugation on-particle ionization/enrichment of phosphopeptides and phosphopeptides were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Weak magnetism of these NPs and a positive surface charge effect at low pH accomplished rapid and selective phosphopeptide enrichment within 30s. Trypsin-digested products of phosphoproteins such as α-casein and β-casein, human blood serum, nonfat milk, and egg white were also investigated to explore their phosphopeptide enrichment from complex samples by this approach. The results demonstrate that NiO NPs exhibit good affinity to trace the phosphopeptides even in the presence of 30 times higher molar concentration of complex solution of non-phosphopeptide proteolytic predigested bovine serum albumin. The detection limits of NiO NPs for α-casein and β-casein were 2.0 × 10(-9) M, with good signal-to-noise ratio in the mass spectrum. NiO NPs were found to be effective and selective for enrichment of singly and multiply phosphorylated peptides at a trace level in complex samples in a microwave oven. The cost of preparing NiO NPs is low, the NiO NPs are thermally stable, and therefore, they hold great promise for use in phosphopeptide enrichment. PMID:21533801

  16. SOIL NITRATE AND AMMONIUM THROUGH 2 YEARS OF SELECTIVE HERBIVORY AND CHRONIC NITROGEN ENRICHMENT

    EPA Science Inventory

    -The effects of increased amounts and flux of bioavailable nitrogenous compounds in the ecosystem is of great interest to ecological researchers and longstanding concern to land-managers. Excess nitrogen in the environment is associated with many large-scale environmental concer...

  17. Larval quality of aquacultured Florida pompano fed rotifers enriched with selected commercial diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest regarding cobia Rachycentron canadum aquaculture in the US has increased greatly in the last decade due to their excellent consumer appeal, extremely rapid growth rates, and the observed success of rearing this species in Taiwan. However, limited information exists with respect to nutritio...

  18. LA-ICP-MS analysis of isolated phosphatic grains indicates selective rare earth element enrichment during reworking and transport processes

    NASA Astrophysics Data System (ADS)

    Auer, Gerald; Reuter, Markus; Hauzenberger, Christoph A.; Piller, Werner E.

    2016-04-01

    water chemistry under certain well constrained circumstances of primary authigenesis. Are these conditions not met, REE patterns are more likely to reflect complex enrichment processes that likely already started to occur during reworking over geologically relatively short time frames. Similarities in the REE patterns of clearly detrital and biogenic phosphate further suggest that the often observed 'hat-shaped' pattern in biogenic phosphates can easily result from increased middle REE (Neodymium to Holmium) scavenging during taphonomic processes prior to final deposition. Finally, cluster analysis coupled with sedimentological considerations proved a valuable tool for the characterization of REE patterns of phosphates in terms of their formation conditions and depositional history, such as the distinction of phosphates formed in situ from reworked and transported phosphate grains.

  19. Characterisation and evaluation of metal-loaded iminodiacetic acid-silica of different porosity for the selective enrichment of phosphopeptides.

    PubMed

    Trojer, L; Stecher, G; Feuerstein, I; Lubbad, S; Bonn, G K

    2005-06-24

    Silica particles of different porosity were functionalised with iminodiacetic acid (IDA) and loaded with Fe(III) to yield immobilised metal affinity chromatography stationary phases (Fe(III)-IDA-silica) for phosphopeptide enrichment. The elution step of bound phosphopeptides was optimised with a 32P radioactive labelled peptide by a comprehensive study. Several elution systems, including phosphate buffers of different pH and concentration and ethylenediaminetetraacetic acid solutions were employed. Furthermore the effect of support porosity on elution behaviour was investigated. Under best conditions recoveries higher than 90% were achieved. A solid-phase extraction (SPE) protocol was developed for fractionation of phosphorylated and non-phosphorylated peptides and desalting of the fractions which is essential for subsequent mass spectrometric analysis by the combination of Fe(III)-IDA-silica and C18-silica particles. The pH of the loading buffer was found to be a critical parameter for the efficiency of the SPE protocol. As tryptic digests of alpha-lactalbumin, lysozyme and ribonuclease A mixed with three synthetic phosphopeptides were fractionated, pH 2.5 provided minimal proportion of unspecific bound peptides when comparing the fractions after mu-LC-electrospray ionization MS separation. The effect of a sample derivatisation reaction (methylation) on the efficiency of phosphopeptide enrichment was further investigated. Blocking carboxylate groups by methyl ester formation totally prevented unspecific interaction with the immobilised Fe(III) ions, but generated partially methylated phosphopeptides that increased the complexity of the phosphorylated fraction. PMID:16038305

  20. Selective enrichment of hypericin in malignant glioma: pioneering in vivo results.

    PubMed

    Noell, Susan; Mayer, Daniel; Strauss, Wolfgang S L; Tatagiba, Marcos S; Ritz, Rainer

    2011-05-01

    Malignant gliomas are diffuse infiltrative growing tumors with a poor prognosis despite treatment with a combination of surgery, radiotherapy and chemotherapy. It has been shown recently that complete tumor resection improves the survival time significantly. Hypericin, a component of St. Johns Wort, is one of the most powerful photosensitizers in nature. The aim of the present study was to investigate accumulation of hypericin in intracerebral implanted malignant glioma in vivo. Rats underwent stereotactic implantation of C6 glioma cells. After intravenous administration of hypericin (5 mg per kg body weight), accumulation of the compound was studied in tumor, the infiltration zone surrounding the tumor and healthy brain (contralateral hemisphere) by fluorescence microscopy between 0 and 48 h after injection. Results were compared by one-way analysis of variance. For post hoc pair-wise comparison the Tukey-Kramer HSD test was used. Accumulation of hypericin was significantly higher in C6 glioma as compared to normal tissue. Maximum hypericin uptake was achieved at 24 h after injection. Ratios of fluorescence intensity between tumor and normal tissue as well as infiltration zone and normal tissue of about 6.1:1 and 1.4:1 were found. Considering tissue auto-fluorescence, fluorescence ratios of about 19.8:1 and 2.5:1 were calculated, respectively. Therefore, hypericin seems to be quite an effective fluorescence marker for the detection of glioma in vivo. To the best of our knowledge, the present study demonstrates for the first time that hypericin accumulates selectively in intracerebral implanted C6 glioma in vivo after systemic (intravenous) administration. PMID:21399870

  1. Stable acetate production in extreme-thermophilic (70°C) mixed culture fermentation by selective enrichment of hydrogenotrophic methanogens

    NASA Astrophysics Data System (ADS)

    Zhang, Fang; Zhang, Yan; Ding, Jing; Dai, Kun; van Loosdrecht, Mark C. M.; Zeng, Raymond J.

    2014-06-01

    The control of metabolite production is difficult in mixed culture fermentation. This is particularly related to hydrogen inhibition. In this work, hydrogenotrophic methanogens were selectively enriched to reduce the hydrogen partial pressure and to realize efficient acetate production in extreme-thermophilic (70°C) mixed culture fermentation. The continuous stirred tank reactor (CSTR) was stable operated during 100 days, in which acetate accounted for more than 90% of metabolites in liquid solutions. The yields of acetate, methane and biomass in CSTR were 1.5 +/- 0.06, 1.0 +/- 0.13 and 0.4 +/- 0.05 mol/mol glucose, respectively, close to the theoretical expected values. The CSTR effluent was stable and no further conversion occurred when incubated for 14 days in a batch reactor. In fed-batch experiments, acetate could be produced up to 34.4 g/L, significantly higher than observed in common hydrogen producing fermentations. Acetate also accounted for more than 90% of soluble products formed in these fed-batch fermentations. The microbial community analysis revealed hydrogenotrophic methanogens (mainly Methanothermobacter thermautotrophicus and Methanobacterium thermoaggregans) as 98% of Archaea, confirming that high temperature will select hydrogenotrophic methanogens over aceticlastic methanogens effectively. This work demonstrated a potential application to effectively produce acetate as a value chemical and methane as an energy gas together via mixed culture fermentation.

  2. Anhydride functionalised calcium ferrite nanoparticles: a new selective magnetic material for enrichment of lead ions from water and food samples.

    PubMed

    Pirouz, Mojgan Jafari; Beyki, Mostafa Hossein; Shemirani, Farzaneh

    2015-03-01

    In this research a sonochemistry route for manufacture of uniform nanocrystalline CaFe2O4 and its anhydride functionalisation were reported. The potential of raw and modified material as a magnetically separable sorbent in selective enrichment of lead ions from water and food samples is outlined. This material was characterised using FT-IR, XRD, SEM and VSM techniques. The SEM and VSM results indicated that the calcium ferrite nanoparticles are sphere-like particles possessing superparamagnetic properties with an average diameter of 40 nm. Various analytical parameters, including pH, contact time, type and concentration of eluent, adsorption capacity, sample volume and interference of ions, were optimised. Following a modification by anhydride, calcium ferrite selectivity toward lead ions was raised more than twofold compared to the unmodified nanoparticles. Finally a pre-concentration procedure was applied for determination of trace Pb(II) in canned tuna fish, canned tomato paste, parsley, milk and well-water samples with satisfactory results. PMID:25306327

  3. Stable acetate production in extreme-thermophilic (70°C) mixed culture fermentation by selective enrichment of hydrogenotrophic methanogens

    PubMed Central

    Zhang, Fang; Zhang, Yan; Ding, Jing; Dai, Kun; van Loosdrecht, Mark C. M.; Zeng, Raymond J.

    2014-01-01

    The control of metabolite production is difficult in mixed culture fermentation. This is particularly related to hydrogen inhibition. In this work, hydrogenotrophic methanogens were selectively enriched to reduce the hydrogen partial pressure and to realize efficient acetate production in extreme-thermophilic (70°C) mixed culture fermentation. The continuous stirred tank reactor (CSTR) was stable operated during 100 days, in which acetate accounted for more than 90% of metabolites in liquid solutions. The yields of acetate, methane and biomass in CSTR were 1.5 ± 0.06, 1.0 ± 0.13 and 0.4 ± 0.05 mol/mol glucose, respectively, close to the theoretical expected values. The CSTR effluent was stable and no further conversion occurred when incubated for 14 days in a batch reactor. In fed-batch experiments, acetate could be produced up to 34.4 g/L, significantly higher than observed in common hydrogen producing fermentations. Acetate also accounted for more than 90% of soluble products formed in these fed-batch fermentations. The microbial community analysis revealed hydrogenotrophic methanogens (mainly Methanothermobacter thermautotrophicus and Methanobacterium thermoaggregans) as 98% of Archaea, confirming that high temperature will select hydrogenotrophic methanogens over aceticlastic methanogens effectively. This work demonstrated a potential application to effectively produce acetate as a value chemical and methane as an energy gas together via mixed culture fermentation. PMID:24920064

  4. Chemostat Enrichments of Human Feces with Resistant Starch Are Selective for Adherent Butyrate-Producing Clostridia at High Dilution Rates

    PubMed Central

    Sharp, Richard; Macfarlane, George T.

    2000-01-01

    Resistant starch (RS) enrichments were made using chemostats inoculated with human feces from two individuals at two dilution rates (D = 0.03 h−1 and D = 0.30 h−1) to select for slow- and fast-growing amylolytic communities. The fermentations were studied by analysis of short-chain fatty acids, amylase and α-glucosidase activities, and viable counts of the predominant culturable populations and the use of 16S rRNA-targeted oligonucleotide probes. Considerable butyrate was produced at D = 0.30 h−1, which corresponded with reduced branched-chain fatty acid formation. At both dilution rates, high levels of extracellular amylase activity were produced, while α-glucosidase was predominantly cell associated. Bacteroides and bifidobacteria predominated at the low dilution rate, whereas saccharolytic clostridia became more important at D = 0.30 h−1. Microscopic examination showed that within 48 h of inoculation, one particular bacterial morphotype predominated in RS enrichments at D = 0.30 h−1. This organism attached apically to RS granules and formed rosette-like structures which, with glycocalyx formation, agglomerated to form biofilm networks in the planktonic phase. Attempts to isolate this bacterium in pure culture were repeatedly unsuccessful, although a single colony was eventually obtained. On the basis of its 16S rDNA sequence, this RS-degrading, butyrate-producing organism was identified as being a previously unidentified group I Clostridium sp. A 16S rRNA-targeted probe was designed using this sequence and used to assess the abundance of the population in the enrichments. At 240 h, its contributions to total rRNA in the chemostats were 5 and 23% at D = 0.03 and 0.30 h−1, respectively. This study indicates that bacterial populations with significant metabolic potential can be overlooked using culture-based methodologies. This may provide a paradigm for explaining the discrepancy between the low numbers of butyrate-producing bacteria that are

  5. New Infestin-4 Mutants with Increased Selectivity against Factor XIIa

    PubMed Central

    Vuimo, Tatiana A.; Surov, Stepan S.; Ovsepyan, Ruzanna A.; Korneeva, Vera A.; Vorobiev, Ivan I.; Orlova, Nadezhda A.; Minakhin, Leonid; Kuznedelov, Konstantin; Severinov, Konstantin V.; Ataullakhanov, Fazoil I.; Panteleev, Mikhail A.

    2015-01-01

    Factor XIIa (fXIIa) is a serine protease that triggers the coagulation contact pathway and plays a role in thrombosis. Because it interferes with coagulation testing, the need to inhibit fXIIa exists in many cases. Infestin-4 (Inf4) is a Kazal-type inhibitor of fXIIa. Its specificity for fXIIa can be enhanced by point mutations in the protease-binding loop. We attempted to adapt Inf4 for the selective repression of the contact pathway under various in vitro conditions, e.g., during blood collection and in ‘global’ assays of tissue factor (TF)-dependent coagulation. First, we designed a set of new Inf4 mutants that, in contrast to wt-Inf4, had stabilized canonical conformations during molecular dynamics simulation. Off-target activities against factor Xa (fXa), plasmin, and other coagulation proteases were either reduced or eliminated in these recombinant mutants, as demonstrated by chromogenic assays. Interactions with fXIIa and fXa were also analyzed using protein-protein docking. Next, Mutant B, one of the most potent mutants (its Ki for fXIIa is 0.7 nM) was tested in plasma. At concentrations 5–20 μM, this mutant delayed the contact-activated generation of thrombin, as well as clotting in thromboelastography and thrombodynamics assays. In these assays, Mutant B did not affect coagulation initiated by TF, thus demonstrating sufficient selectivity and its potential practical significance as a reagent for coagulation diagnostics. PMID:26670620

  6. Pain tolerance selectively increased by a sweet-smelling odor.

    PubMed

    Prescott, John; Wilkie, Jenell

    2007-04-01

    The mechanism underlying reported analgesic effects of odors in humans is unclear, although odor hedonics has been implicated. We tested whether odors that are sweet smelling through prior association with tasted sweetness might influence pain by activating the same analgesic mechanisms as sweet tastes. Inhalation of a sweet-smelling odor during a cold-pressor test increased tolerance for pain compared with inhalation of pleasant and unpleasant low-sweetness odors and no odor. There were no significant differences in pain ratings among the odor conditions. These results suggest that smelled sweetness can produce a naturally occurring conditioned increase in pain tolerance. PMID:17470253

  7. Increased calf production in cattle selected for twin ovulations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of increasing fetal numbers and their distribution between the left and right uterine horns on calf survival, calf BW at birth and weaning, gestation length, dystocia, and calf sex ratio were evaluated for single (n = 1,587), twin (n = 2,440), and triplet calves (n = 147) born to primipa...

  8. By their words ye shall know them: Evidence of genetic selection against general intelligence and concurrent environmental enrichment in vocabulary usage since the mid 19th century

    PubMed Central

    Menie, Michael A. Woodley of; Fernandes, Heitor B. F.; José Figueredo, Aurelio; Meisenberg, Gerhard

    2015-01-01

    It has been theorized that declines in general intelligence (g) due to genetic selection stemming from the inverse association between completed fertility and IQ and the Flynn effect co-occur, with the effects of the latter being concentrated on less heritable non-g sources of intelligence variance. Evidence for this comes from the observation that 19th century populations were more intellectually productive, and also exhibited faster simple reaction times than modern ones, suggesting greater information-processing ability and therefore higher g. This co-occurrence model is tested via examination of historical changes in the utilization frequencies of words from the highly g-loaded WORDSUM test across 5.9 million texts spanning the period 1850–2005. Consistent with predictions, words with higher difficulties (δ parameters from Item Response Theory) and stronger negative correlations between pass rates and completed fertility declined in use over time whereas less difficult and less strongly selected words, increased in use over time, consistent with a Flynn effect stemming in part from the vocabulary enriching effects of increases in population literacy. These findings persisted when explicitly controlled for word age, changing literacy rates and temporal autocorrelation. These trends constitute compelling evidence for the co-occurrence model. PMID:25954211

  9. By their words ye shall know them: Evidence of genetic selection against general intelligence and concurrent environmental enrichment in vocabulary usage since the mid 19th century.

    PubMed

    Menie, Michael A Woodley Of; Fernandes, Heitor B F; José Figueredo, Aurelio; Meisenberg, Gerhard

    2015-01-01

    It has been theorized that declines in general intelligence (g) due to genetic selection stemming from the inverse association between completed fertility and IQ and the Flynn effect co-occur, with the effects of the latter being concentrated on less heritable non-g sources of intelligence variance. Evidence for this comes from the observation that 19th century populations were more intellectually productive, and also exhibited faster simple reaction times than modern ones, suggesting greater information-processing ability and therefore higher g. This co-occurrence model is tested via examination of historical changes in the utilization frequencies of words from the highly g-loaded WORDSUM test across 5.9 million texts spanning the period 1850-2005. Consistent with predictions, words with higher difficulties (δ parameters from Item Response Theory) and stronger negative correlations between pass rates and completed fertility declined in use over time whereas less difficult and less strongly selected words, increased in use over time, consistent with a Flynn effect stemming in part from the vocabulary enriching effects of increases in population literacy. These findings persisted when explicitly controlled for word age, changing literacy rates and temporal autocorrelation. These trends constitute compelling evidence for the co-occurrence model. PMID:25954211

  10. Detection of Burkholderia pseudomallei in Sputum using Selective Enrichment Broth and Ashdown’s Medium at Kampong Cham Provincial Hospital, Cambodia

    PubMed Central

    Nhem, Somary; Letchford, Joanne; Meas, Chea; Thann, Sovanndeth; McLaughlin, James C.; Baron, Ellen Jo; West, T. Eoin

    2015-01-01

    Melioidosis, infection caused by Burkholderia pseudomallei, is increasingly reported in Cambodia. We hypothesized that implementation of an enhanced sputum testing protocol in a provincial hospital diagnostic microbiology laboratory would increase detection of B. pseudomallei. We tested 241 sputum specimens that were deemed acceptable for culture, comparing culture in selective enrichment broth followed by sub-culture on Ashdown’s medium to standard culture methods. Two specimens (0.8%) were positive for B. pseudomallei using the enhanced protocol whereas one specimen (0.4%) was positive using standard methods. Given the low numbers of positive specimens, we could not conclusively determine the utility of the enhanced sputum testing protocol. However, the ramifications of identification of  B. pseudomallei are substantial, and the benefit of the enhanced testing protocol may be more apparent in patients selected based on risk factors and clinical presentation. Promoting clinician awareness of the infection and encouraging utilization of diagnostic microbiology services are also likely to be important factors in facilitating identification of melioidosis. PMID:25717370

  11. Fine-scale selection by ovipositing females increases egg survival

    PubMed Central

    Gall, Brian G; Brodie, Edmund D; Brodie, Edmund D

    2012-01-01

    One of the most important defenses for the eggs of ovipositing female organisms is to avoid being laid in the same habitat as their predators. However, for most organisms, completely avoiding an offspring's predators is not possible. One mechanism that has been largely overlooked is for females to partition an oviposition site into microhabitats that differ in quality for offspring survival. We conducted a series of experiments to examine whether female newts avoid microhabitats utilized by their offspring's primary predator, caddisfly larvae. Female newts avoided laying eggs near predatory caddisflies and shifted egg laying upward in the water column when provided with a vertical dimension. Caddisflies were attracted to chemical stimuli from female newts and their eggs, yet primarily used benthic areas in experimental chambers. Finally, results from a field experiment indicate that the behavioral strategy employed by female newts increases offspring survival. This subset of non-genetic maternal effects, micro-oviposition avoidance, is likely an important yet underexplored mechanism by which females increase offspring survival. PMID:23170211

  12. Transplanted Dentate Progenitor Cells Show Increased Survival in an Enriched Environment But Do Not Exert a Neurotrophic Effect on Spatial Memory Within 2 Weeks of Engraftment.

    PubMed

    Jamal, Amanda L; Walker, Tara L; Waber Nguyen, Amanda J; Berman, Robert F; Kempermann, Gerd; Waldau, Ben

    2015-01-01

    Cyclin D2 knockout mice show decreased levels of endogenous dentate neurogenesis. We investigated whether transplanted dentate progenitor cells from wild-type mice respond in vivo to an enriched environment and whether they improve deficient dentate neurogenesis through a neurotrophic effect. Adult cyclin D2 knockout mice were transplanted with passaged adult progenitor cells and kept in an enriched environment or under standard housing conditions in isolation. After 1 week, animals living in an enriched environment underwent water maze testing. Progenitor cells grown on a laminin/poly-d-lysine monolayer expressed Sox2 and nestin and could be differentiated in vitro into neurons and astrocytes. After transplantation into the dentate gyrus, cells preferentially survived along the laminin-rich ependymal lining of the basal cistern or basal membrane of capillaries. A subpopulation of transplanted cells migrated into the interstitial space of the hippocampus and was not associated with laminin. Environmental enrichment led to a significant increase in the survival of transplanted progenitor cells on laminin in the dentate gyrus after 2 weeks. However, animals did not show an enhanced performance in the Morris water maze, and transplantation failed to exert a neurotrophic effect on endogenous neurogenesis after 2 weeks. However, a major limitation of the study is the short-term period of investigation, which may have been insufficient to capture functional effects. In conclusion, initial survival of transplanted neural progenitor cells was dependent on the presence of laminin and was significantly enhanced by environmental enrichment. Further studies are needed to address whether an enriched environment continues to promote graft survival over longer periods of time. PMID:25621922

  13. HETEROGENEITY OF HUMAN NATURAL KILLER (NK) CELLS: ENRICHMENT OF NK BY NEGATIVE-SELECTION WITH THE LECTIN FROM 'ERYTHRINA CRISTAGALLI' (JOURNAL VERSION)

    EPA Science Inventory

    A novel technique for the isolation and enrichment of human natural killer (NK) cells from peripheral blood mononuclear cells (MNC) is described. Negative selection of MNC with the lectin from Erythrina cristagalli (ECA), whether by panning or agglutination in solution, resulted ...

  14. Selective trace enrichment of chlorotriazine pesticides from natural waters and sediment samples using terbuthylazine molecularly imprinted polymers

    USGS Publications Warehouse

    Ferrer, I.; Lanza, F.; Tolokan, A.; Horvath, V.; Sellergren, B.; Horvai, G.; Barcelo, D.

    2000-01-01

    Two molecularly imprinted polymers were synthesized using either dichloromethane or toluene as the porogen and terbuthylazine as the template and were used as solid-phase extraction cartridges for the enrichment of six chlorotriazines (deisopropylatrazine, deethylatrazine, simazine, atrazine, propazine, and terbuthylazine) in natural water and sediment samples. The extracted samples were analyzed by liquid chromatography/diode array detection (LC/DAD). Several washing solvents, as well as different volumes, were tested for their ability to remove the matrix components nonspecifically adsorbed on the sorbents. This cleanup step was shown to be of prime importance to the successful extraction of the pesticides from the aqueous samples. The optimal analytical conditions were obtained when the MIP imprinted using dichloromethane was the sorbent, 2 mL of dichloromethane was used in the washing step, and the preconcentrated analytes were eluted with 8 mL of methanol. The recoveries were higher than 80% for all the chlorotriazines except for propazine (53%) when 50- or 100-mL groundwater samples, spiked at 1 ??g/L level, were analyzed. The limits of detection varied from 0.05 to 0.2 ??g/L when preconcentrating a 100-mL groundwater sample. Natural sediment samples from the Ebre Delta area (Tarragona, Spain) containing atrazine and deethylatrazine were Soxhlet extracted and analyzed by the methodology developed in this work. No significant interferences from the sample matrix were noticed, thus indicating good selectivity of the MIP sorbents used.

  15. Novel core-shell cerium(IV)-immobilized magnetic polymeric microspheres for selective enrichment and rapid separation of phosphopeptides.

    PubMed

    Wang, Zhi-Gang; Cheng, Gong; Liu, Yan-Lin; Zhang, Ji-Lin; Sun, De-Hui; Ni, Jia-Zuan

    2014-03-01

    In this work, novel magnetic polymeric core-shell structured microspheres with immobilized Ce(IV), Fe3O4@SiO2@PVPA-Ce(IV), were designed rationally and synthesized successfully via a facile route for the first time. Magnetic Fe3O4@SiO2 microspheres were first prepared by directly coating a thin layer of silica onto Fe3O4 magnetic particles using a sol-gel method, a poly(vinylphosphonic acid) (PVPA) shell was then coated on the Fe3O4@SiO2 microspheres to form Fe3O4@SiO2@PVPA microspheres through a radical polymerization reaction, and finally Ce(IV) ions were robustly immobilized onto the Fe3O4@SiO2@PVPA microspheres through strong chelation between Ce(IV) ions and phosphate moieties in the PVPA. The applicability of the Fe3O4@SiO2@PVPA-Ce(IV) microspheres for selective enrichment and rapid separation of phosphopeptides from proteolytic digests of standard and real protein samples was investigated. The results demonstrated that the core-shell structured Fe3O4@SiO2@PVPA-Ce(IV) microspheres with abundant Ce(IV) affinity sites and excellent magnetic responsiveness can effectively purify phosphopeptides from complex biosamples for MS detection taking advantage of the rapid magnetic separation and the selective affinity between Ce(IV) ions and phosphate moieties of the phosphopeptides. Furthermore, they can be effectively recycled and show good reusability, and have better performance than commercial TiO2 beads and homemade Fe3O4@PMAA-Ce(IV) microspheres. Thus the Fe3O4@SiO2@PVPA-Ce(IV) microspheres can benefit greatly the mass spectrometric qualitative analysis of phosphopeptides in phosphoproteome research. PMID:24407680

  16. Tailor-made magnetic Fe3O4@mTiO2 microspheres with a tunable mesoporous anatase shell for highly selective and effective enrichment of phosphopeptides.

    PubMed

    Ma, Wan-Fu; Zhang, Ying; Li, Lu-Lu; You, Li-Jun; Zhang, Peng; Zhang, Yu-Ting; Li, Ju-Mei; Yu, Meng; Guo, Jia; Lu, Hao-Jie; Wang, Chang-Chun

    2012-04-24

    Selective enrichment of phosphoproteins or phosphopeptides from complex mixtures is essential for MS-based phosphoproteomics, but still remains a challenge. In this article, we described an unprecedented approach to synthesize magnetic mesoporous Fe(3)O(4)@mTiO(2) microspheres with a well-defined core/shell structure, a pure and highly crystalline TiO(2) layer, high specific surface area (167.1 m(2)/g), large pore volume (0.45 cm(3)/g), appropriate and tunable pore size (8.6-16.4 nm), and high magnetic susceptibility. We investigated the applicability of Fe(3)O(4)@mTiO(2) microspheres in a study of the selective enrichment of phosphopeptides. The experiment results demonstrated that the Fe(3)O(4)@mTiO(2) possessed remarkable selectivity for phosphopeptides even at a very low molar ratio of phosphopeptides/non-phosphopeptides (1:1000), large enrichment capacity (as high as 225 mg/g, over 10 times as that of the Fe(3)O(4)@TiO(2) microspheres), extreme sensitivity (the detection limit was at the fmol level), excellent speed (the enrichment can be completed in less than 5 min), and high recovery of phosphopeptides (as high as 93%). In addition, the high magnetic susceptibility allowed convenient separation of the target peptides by magnetic separation. These outstanding features give the Fe(3)O(4)@mTiO(2) composite microspheres high benefit for mass spectrometric analysis of phosphopeptides. PMID:22452444

  17. Hydrophilic Nb⁵⁺-immobilized magnetic core-shell microsphere--A novel immobilized metal ion affinity chromatography material for highly selective enrichment of phosphopeptides.

    PubMed

    Sun, Xueni; Liu, Xiaodan; Feng, Jianan; Li, Yan; Deng, Chunhui; Duan, Gengli

    2015-06-23

    Rapid and selective enrichment of phosphopeptides from complex biological samples is essential and challenging in phosphorylated proteomics. In this work, for the first time, niobium ions were directly immobilized on the surface of polydopamine-coated magnetic microspheres through a facile and effective synthetic route. The Fe3O4@polydopamine-Nb(5+) (denoted as Fe3O4@PD-Nb(5+)) microspheres possess merits of high hydrophilicity and good biological compatibility, and demonstrated low limit of detection (2 fmol). The selectivity was also basically satisfactory (β-casein:BSA=1:500) to capture phosphopeptides. They were also successfully applied for enrichment of phosphopeptides from real biological samples such as human serum and nonfat milk. Compared with Fe3O4@PD-Ti(4+) microspheres, the Fe3O4@PD-Nb(5+) microspheres exhibit superior selectivity to multi-phosphorylated peptides, and thus may be complementary to the conventional IMAC materials. PMID:26092339

  18. Does anthropogenic nitrogen enrichment increase organic nitrogen concentrations in runoff from forested and human-dominated watersheds?

    USGS Publications Warehouse

    Pellerin, B.A.; Kaushal, S.S.; McDowell, W.H.

    2006-01-01

    Although the effects of anthropogenic nitrogen (N) inputs on the dynamics of inorganic N in watersheds have been studied extensively, "the influence of N enrichment on organic N loss" is not as well understood. We compiled and synthesized data on surface water N concentrations from 348 forested and human-dominated watersheds with a range of N loads (from less than 100 to 7,100 kg N km-2 y-1) to evaluate the effects of N loading via atmospheric deposition, fertilization, and wastewater on dissolved organic N (DON) concentrations. Our results indicate that, on average, DON accounts for half of the total dissolved N (TDN) concentrations from forested watersheds, but it accounts for a smaller fraction of TDN in runoff from urban and agricultural watersheds with higher N loading. A significant but weak correlation (r 2 = 0.06) suggests that N loading has little influence on DON concentrations in forested watersheds. This result contrasts with observations from some plot-scale N fertilization studies and suggests that variability in watershed characteristics and climate among forested watersheds may be a more important control on DON losses than N loading from atmospheric sources. Mean DON concentrations were positively correlated, however, with N load across the entire land-use gradient (r 2 = 0.37, P < 0.01), with the highest concentrations found in agricultural and urban watersheds. We hypothesize that both direct contributions of DON from wastewater and agricultural amendments and indirect transformations of inorganic N to organic N represent important sources of DON to surface waters in human-dominated watersheds. We conclude that DON is an important component of N loss in surface waters draining forested and human-dominated watersheds and suggest several research priorities that may be useful in elucidating the role of N enrichment in watershed DON dynamics. ?? 2006 Springer Science+Business Media, Inc.

  19. Synthesis of Fe3O4/graphene/TiO2 composites for the highly selective enrichment of phosphopeptides from biological samples.

    PubMed

    Lu, Jin; Deng, Chunhui; Zhang, Xiangmin; Yang, Pengyuan

    2013-08-14

    In this work, Fe3O4/graphene/TiO2 composites with a large surface area were designed and synthesized for the selective extraction and enrichment of phosphopeptides from biological samples. First, magnetic graphene was prepared according to our previous method. Next, we made the Fe3O4/graphene/TiO2 composite precursor using tetrabutyl titanate. Fe3O4/graphene/TiO2 composites were obtained after solvothermal and calcination treatments. We used standard protein-digestion solutions and human liver samples to test the enrichment ability of the obtained Fe3O4/graphene/TiO2 composites. The experimental results demonstrate that Fe3O4/graphene/TiO2 composites have a good phosphopeptide enrichment ability. PMID:23883739

  20. Charge-selective gate of arrayed MWCNTs for ultra high-efficient biomolecule enrichment by nano-electrostatic sieving (NES).

    PubMed

    Wu, Jen-Kuei; Wu, Yi-Shiuan; Yang, Chung-Shi; Tseng, Fan-Gang

    2013-05-15

    We report a rapid and highly-efficient biomolecule preconcentrating device based on nano-electrostatic sieving (NES) mechanism that is facilitated by multi-nanofluidic channels operated in parallel. The opening of these nanochannels is regulated by tunable charges that are generated on arrayed multi-walled carbon nanotubes (MWCNTs) gate. The NES device is fabricated by standard photolithography and plasma-enhanced chemical vapor deposition (PECVD) techniques, followed by subsequent deposition of parylene (poly(p-xylylene))-C on vertically grown MWCNTs in order to obtain arrayed multi-nanochannels with mean pore sizes that are comparable to the thickness of an electrical double layer (EDL). The enrichment efficiency for charged analytes is dependent on electrostatic repulsion, which is regulated by the distribution of the local electric field on the MWCNTs gate. The NES device exhibits polarity selectivity on the analytes and performs efficient collection and separation of biomolecules by probing the surface charge density dependence on the applied gate field. A tunable gate of the parylene-MWCNT nanochannels was used as size sieving devices for nano-scale biomolecules. The experimental results for the collection of FITC-labeled bovine serum albumin (BSA, 0.033nM) were as high as nearly 10(6) fold after only 45min. These data are attributed to the in-parallel molecule sieving process as conducted by the many nanochannels formed among the MWCNTs. This device allows uncharged polar molecules, such as water, to rapidly pass through thus enable highly efficient bio-molecule concentration for the application to ultra-high sensitive biosensing. PMID:23391690

  1. Selenium-enriched Agaricus bisporus increases expression and activity of glutathione peroxidase-1 and expression of glutathione peroxidase-2 in rat colon.

    PubMed

    Maseko, Tebo; Howell, Kate; Dunshea, Frank R; Ng, Ken

    2014-03-01

    The effect of dietary supplementation with Se-enriched Agaricus bisporus on cytosolic gluthathione peroxidase-1 (GPx-1), gastrointestinal specific glutathione peroxidase-2 (GPx-2), thioredoxin reductase-1 (TrxR-1) and selenoprotein P (SeP) mRNA expression and GPx-1 enzyme activity in rat colon was examined. Rats were fed for 5weeks with control diet (0.15μg Se/g feed) or Se-enriched diet fortified with selenised mushroom (1μg Se/g feed). The mRNA expression levels were found to be significantly (P<0.01) up-regulated by 1.65-fold and 2.3-fold for GPx-1 and GPx-2, respectively, but were not significantly different for TrxR-1 and SeP between the 2 diet treatments. The up-regulation of GPx-1 mRNA expression was consistent with GPX-1 activity level, which was significantly (P<0.05) increased by 1.77-fold in rats fed with the Se-enriched diet compared to the control diet. The results showed that selenised A. bisporus can positively increase GPx-1 and GPx-2 gene expression and GPx-1 enzyme activity in rat colon. PMID:24176350

  2. The Impact of Carrot Enriched in Iodine through Soil Fertilization on Iodine Concentration and Selected Biochemical Parameters in Wistar Rats.

    PubMed

    Piątkowska, Ewa; Kopeć, Aneta; Bieżanowska-Kopeć, Renata; Pysz, Mirosław; Kapusta-Duch, Joanna; Koronowicz, Aneta Agnieszka; Smoleń, Sylwester; Skoczylas, Łukasz; Ledwożyw-Smoleń, Iwona; Rakoczy, Roksana; Maślak, Edyta

    2016-01-01

    Iodine is one of the trace elements which are essential for mammalian life. The major objective of iodine biofortification of plants is to obtain food rich in this trace element, which may increase its consumption by various populations. Additionally, it may reduce the risk of iodine deficiency diseases. In this research for the first time we have assessed the bioavailability of iodine from raw or cooked carrot biofortified with this trace element on iodine concentration in selected tissues and various biochemical parameters as well as mRNA expression of some genes involved in iodine metabolism in Wistar rats. Statistically, a significantly higher iodine level was determined in urine, faeces and selected tissues of rats fed a diet containing biofortified raw carrot as compared to a diet without iodine and a diet containing control cooked carrot. Biofortified raw carrot significantly increased triiodothyronine concentration as compared to animals from other experimental groups. The highest thyroid stimulating hormone level was determined in rats fed control cooked carrots. mRNA expression of selected genes was affected by different dietary treatment in rats' hearts. Biofortified raw and cooked carrot could be taken into account as a potential source of iodine in daily diets to prevent iodine deficiency in various populations. PMID:27043135

  3. The Impact of Carrot Enriched in Iodine through Soil Fertilization on Iodine Concentration and Selected Biochemical Parameters in Wistar Rats

    PubMed Central

    Piątkowska, Ewa; Kopeć, Aneta; Bieżanowska-Kopeć, Renata; Pysz, Mirosław; Kapusta-Duch, Joanna; Koronowicz, Aneta Agnieszka; Smoleń, Sylwester; Skoczylas, Łukasz; Ledwożyw-Smoleń, Iwona; Rakoczy, Roksana; Maślak, Edyta

    2016-01-01

    Iodine is one of the trace elements which are essential for mammalian life. The major objective of iodine biofortification of plants is to obtain food rich in this trace element, which may increase its consumption by various populations. Additionally, it may reduce the risk of iodine deficiency diseases. In this research for the first time we have assessed the bioavailability of iodine from raw or cooked carrot biofortified with this trace element on iodine concentration in selected tissues and various biochemical parameters as well as mRNA expression of some genes involved in iodine metabolism in Wistar rats. Statistically, a significantly higher iodine level was determined in urine, faeces and selected tissues of rats fed a diet containing biofortified raw carrot as compared to a diet without iodine and a diet containing control cooked carrot. Biofortified raw carrot significantly increased triiodothyronine concentration as compared to animals from other experimental groups. The highest thyroid stimulating hormone level was determined in rats fed control cooked carrots. mRNA expression of selected genes was affected by different dietary treatment in rats’ hearts. Biofortified raw and cooked carrot could be taken into account as a potential source of iodine in daily diets to prevent iodine deficiency in various populations. PMID:27043135

  4. Ultrasound and phenotypic measures of the reproductive tract of prepubertal gilts selected for increased uterine capacity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Direct selection for uterine capacity (UC) increases litter size without altering ovulation rate. A method to estimate UC in developing gilts would be beneficial for commercial selection strategies. We tested the hypothesis that selection for UC alters phenotypic characteristics of the reproductiv...

  5. Selective enrichment of environmental DNA libraries for genes encoding nonribosomal peptides and polyketides by phosphopantetheine transferase-dependent complementation of siderophore biosynthesis

    PubMed Central

    Charlop-Powers, Zachary; Banik, Jacob J.; Owen, Jeremy G.; Craig, Jeffrey W.; Brady, Sean F.

    2012-01-01

    The cloning of DNA directly from environmental samples provides a means to functionally access biosynthetic gene clusters present in the genomes of the large fraction of bacteria that remains recalcitrant to growth in the laboratory. Herein we demonstrate a method by which complementation of phosphopantetheine transferase deletion mutants can be used to restore siderophore biosynthesis and to therefore selectively enrich eDNA libraries for nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) gene sequences to unprecedented levels. The common use of NRPS/PKS-derived siderophores across bacterial taxa makes this method generalizable and should allow for the facile selective enrichment of NRPS/PKS-containing biosynthetic gene clusters from large environmental DNA libraries using a wide variety of phylogenetically diverse bacterial hosts. PMID:23072412

  6. Enrichment culture for the isolation of Campylobacter spp: Effects of incubation conditions and the inclusion of blood in selective broths.

    PubMed

    Williams, Lisa K; Jørgensen, Frieda; Grogono-Thomas, Rose; Humphrey, Tom J

    2009-03-31

    Isolation of Campylobacter spp. using enrichment culture is time consuming and complex. Reducing the time taken to confirm the presence or absence of Campylobacter spp. would have many advantages for diagnostic, commercial and research applications. Rapid techniques such as real-time PCR can detect campylobacters from complex samples but blood in enrichment culture can inhibit the PCR reaction, if applied directly to enriched samples. The aim of this study was to investigate the effect of blood in enrichment culture on the isolation of campylobacters from chicken caeca, carcass rinses and bootsock (gauze sock walked through a broiler chicken house) samples using Bolton broth. The effect of incubation temperature (37 degrees C or 41.5 degrees C for 48 h, or 37 degrees C for 4 h then transfer to 41.5 degrees C for 44 h) and method of generating atmosphere (incubation of container in jar gassed with microaerobic atmosphere or incubation of container with small headspace and tightly screwed lid in an aerobic atmosphere) with and without blood on isolation from chicken carcass rinses and chicken faeces was also investigated. The presence of blood in enrichment culture did not improve the isolation of campylobacters from chicken faeces or bootsock samples but significantly improved recovery from chicken carcass rinse samples. There was no significant effect of the method used to generate incubation atmosphere. Isolation rates did also not depend significantly on whether broths were incubated at 37 or 41.5 degrees C for 24 or 48 h. Overall, the presence of blood in such media is not essential, although isolation can vary depending on sample type and enrichment method used. PMID:19217181

  7. Multiplex Real-Time PCR for Detection of Staphylococcus aureus, mecA and Panton-Valentine Leukocidin (PVL) Genes from Selective Enrichments from Animals and Retail Meat

    PubMed Central

    Velasco, Valeria; Sherwood, Julie S.; Rojas-García, Pedro P.; Logue, Catherine M.

    2014-01-01

    The aim of this study was to compare a real-time PCR assay, with a conventional culture/PCR method, to detect S. aureus, mecA and Panton-Valentine Leukocidin (PVL) genes in animals and retail meat, using a two-step selective enrichment protocol. A total of 234 samples were examined (77 animal nasal swabs, 112 retail raw meat, and 45 deli meat). The multiplex real-time PCR targeted the genes: nuc (identification of S. aureus), mecA (associated with methicillin resistance) and PVL (virulence factor), and the primary and secondary enrichment samples were assessed. The conventional culture/PCR method included the two-step selective enrichment, selective plating, biochemical testing, and multiplex PCR for confirmation. The conventional culture/PCR method recovered 95/234 positive S. aureus samples. Application of real-time PCR on samples following primary and secondary enrichment detected S. aureus in 111/234 and 120/234 samples respectively. For detection of S. aureus, the kappa statistic was 0.68–0.88 (from substantial to almost perfect agreement) and 0.29–0.77 (from fair to substantial agreement) for primary and secondary enrichments, using real-time PCR. For detection of mecA gene, the kappa statistic was 0–0.49 (from no agreement beyond that expected by chance to moderate agreement) for primary and secondary enrichment samples. Two pork samples were mecA gene positive by all methods. The real-time PCR assay detected the mecA gene in samples that were negative for S. aureus, but positive for Staphylococcus spp. The PVL gene was not detected in any sample by the conventional culture/PCR method or the real-time PCR assay. Among S. aureus isolated by conventional culture/PCR method, the sequence type ST398, and multi-drug resistant strains were found in animals and raw meat samples. The real-time PCR assay may be recommended as a rapid method for detection of S. aureus and the mecA gene, with further confirmation of methicillin-resistant S. aureus (MRSA) using

  8. Discovery of novel mGluR1 antagonists: a multistep virtual screening approach based on an SVM model and a pharmacophore hypothesis significantly increases the hit rate and enrichment factor.

    PubMed

    Li, Guo-Bo; Yang, Ling-Ling; Feng, Shan; Zhou, Jian-Ping; Huang, Qi; Xie, Huan-Zhang; Li, Lin-Li; Yang, Sheng-Yong

    2011-03-15

    Development of glutamate non-competitive antagonists of mGluR1 (Metabotropic glutamate receptor subtype 1) has increasingly attracted much attention in recent years due to their potential therapeutic application for various nervous disorders. Since there is no crystal structure reported for mGluR1, ligand-based virtual screening (VS) methods, typically pharmacophore-based VS (PB-VS), are often used for the discovery of mGluR1 antagonists. Nevertheless, PB-VS usually suffers a lower hit rate and enrichment factor. In this investigation, we established a multistep ligand-based VS approach that is based on a support vector machine (SVM) classification model and a pharmacophore model. Performance evaluation of these methods in virtual screening against a large independent test set, M-MDDR, show that the multistep VS approach significantly increases the hit rate and enrichment factor compared with the individual SB-VS and PB-VS methods. The multistep VS approach was then used to screen several large chemical libraries including PubChem, Specs, and Enamine. Finally a total of 20 compounds were selected from the top ranking compounds, and shifted to the subsequent in vitro and in vivo studies, which results will be reported in the near future. PMID:21316965

  9. Preparation and application of a novel molecularly imprinted solid-phase microextraction monolith for selective enrichment of cholecystokinin neuropeptides in human cerebrospinal fluid.

    PubMed

    Ji, Xiang; Li, Dan; Li, Hua

    2015-08-01

    A novel molecularly imprinted polymer (MIP) monolith for highly selective extraction of cholecystokinin (CCK) neuropeptides was prepared in a micropipette tip. The MIPs were synthesized by epitope imprinting technique and the polymerization conditions were investigated and optimized. The synthesized MIPs were characterized by infrared spectroscopy, elemental analyzer and scanning electron microscope. A molecularly imprinted solid-phase microextraction (MI-μ-SPE) method was developed for the extraction of CCK neuropeptides in aqueous solutions. The parameters affecting MI-μ-SPE were optimized. The results indicated that this MIP monolith exhibited specific recognition capability and high enrichment efficiency for CCK neuropeptides. In addition, it showed excellent reusability. This MIP monolith was used for desalting and enrichment of CCK4, CCK5 and CCK8 from human cerebrospinal fluid prior to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, and the results show that this MIP monolith can be a useful tool for effective purification and highly selective enrichment of multiple homologous CCK neuropeptides in cerebrospinal fluid simultaneously. By employing MI-μ-SPE combined with HPLC-ESI-MS/MS analysis, endogenous CCK4 in human cerebrospinal fluid was quantified. PMID:25616243

  10. Bound simian virus 40 translocates to caveolin-enriched membrane domains, and its entry is inhibited by drugs that selectively disrupt caveolae.

    PubMed Central

    Anderson, H A; Chen, Y; Norkin, L C

    1996-01-01

    Simian virus 40 (SV40) entry leading to infection occurred only after the virus was at the cell surface for 1.5 to 2 h. SV40 infectious entry was not sensitive to cytosol acidification, a treatment that blocks endocytosis via clathrin-coated vesicles. Instead, SV40 infectious entry was blocked by treating cells with the phorbol ester PMA or nystatin, which selectively disrupts caveolae. In control experiments, transferrin internalization was sensitive to cytosol acidification but was not sensitive to PMA or nystatin. Also, absorbed transferrin entered cells within minutes. Finally, bound SV40 translocated to caveolin-enriched membrane complexes isolated by a Triton X-100 insolubility protocol. Treatment with nystatin did not impair SV40 binding but did block the partitioning of virus into the caveolin-enriched complexes. Images PMID:8930903

  11. Not All Particles Are Equal: The Selective Enrichment of Particle-Associated Bacteria from the Mediterranean Sea.

    PubMed

    López-Pérez, Mario; Kimes, Nikole E; Haro-Moreno, Jose M; Rodriguez-Valera, Francisco

    2016-01-01

    We have used two metagenomic approaches, direct sequencing of natural samples and sequencing after enrichment, to characterize communities of prokaryotes associated to particles. In the first approximation, different size filters (0.22 and 5 μm) were used to identify prokaryotic microbes of free-living and particle-attached bacterial communities in the Mediterranean water column. A subtractive metagenomic approach was used to characterize the dominant microbial groups in the large size fraction that were not present in the free-living one. They belonged mainly to Actinobacteria, Planctomycetes, Flavobacteria and Proteobacteria. In addition, marine microbial communities enriched by incubation with different kinds of particulate material have been studied by metagenomic assembly. Different particle kinds (diatomaceous earth, sand, chitin and cellulose) were colonized by very different communities of bacteria belonging to Roseobacter, Vibrio, Bacteriovorax, and Lacinutrix that were distant relatives of genomes already described from marine habitats. Besides, using assembly from deep metagenomic sequencing from the particle-specific enrichments we were able to determine a total of 20 groups of contigs (eight of them with >50% completeness) and reconstruct de novo five new genomes of novel species within marine clades (>79% completeness and <1.8% contamination). We also describe for the first time the genome of a marine Rhizobiales phage that seems to infect a broad range of Alphaproteobacteria and live in habitats as diverse as soil, marine sediment and water column. The metagenomic recruitment of the communities found by direct sequencing of the large size filter and by enrichment had nearly no overlap. These results indicate that these reconstructed genomes are part of the rare biosphere which exists at nominal levels under natural conditions. PMID:27446036

  12. Not All Particles Are Equal: The Selective Enrichment of Particle-Associated Bacteria from the Mediterranean Sea

    PubMed Central

    López-Pérez, Mario; Kimes, Nikole E.; Haro-Moreno, Jose M.; Rodriguez-Valera, Francisco

    2016-01-01

    We have used two metagenomic approaches, direct sequencing of natural samples and sequencing after enrichment, to characterize communities of prokaryotes associated to particles. In the first approximation, different size filters (0.22 and 5 μm) were used to identify prokaryotic microbes of free-living and particle-attached bacterial communities in the Mediterranean water column. A subtractive metagenomic approach was used to characterize the dominant microbial groups in the large size fraction that were not present in the free-living one. They belonged mainly to Actinobacteria, Planctomycetes, Flavobacteria and Proteobacteria. In addition, marine microbial communities enriched by incubation with different kinds of particulate material have been studied by metagenomic assembly. Different particle kinds (diatomaceous earth, sand, chitin and cellulose) were colonized by very different communities of bacteria belonging to Roseobacter, Vibrio, Bacteriovorax, and Lacinutrix that were distant relatives of genomes already described from marine habitats. Besides, using assembly from deep metagenomic sequencing from the particle-specific enrichments we were able to determine a total of 20 groups of contigs (eight of them with >50% completeness) and reconstruct de novo five new genomes of novel species within marine clades (>79% completeness and <1.8% contamination). We also describe for the first time the genome of a marine Rhizobiales phage that seems to infect a broad range of Alphaproteobacteria and live in habitats as diverse as soil, marine sediment and water column. The metagenomic recruitment of the communities found by direct sequencing of the large size filter and by enrichment had nearly no overlap. These results indicate that these reconstructed genomes are part of the rare biosphere which exists at nominal levels under natural conditions. PMID:27446036

  13. Enriching the drinking water of rats with extracts of Salvia officinalis and Thymus vulgaris increases their resistance to oxidative stress.

    PubMed

    Horváthová, Eva; Srančíková, Annamária; Regendová-Sedláčková, Eva; Melušová, Martina; Meluš, Vladimír; Netriová, Jana; Krajčovičová, Zdenka; Slameňová, Darina; Pastorek, Michal; Kozics, Katarína

    2016-01-01

    Nature is an attractive source of therapeutic compounds. In comparison to the artificial drugs, natural compounds cause less adverse side effects and are suitable for current molecularly oriented approaches to drug development and their mutual combining. Medicinal plants represent one of the most available remedy against various diseases. Proper examples are Salvia officinalis L. and Thymus vulgaris L. which are known aromatic medicinal plants. They are very popular and frequently used in many countries. The molecular mechanism of their biological activity has not yet been fully understood. The aim of this study was to ascertain if liver cells of experimental animals drinking extracts of sage or thyme will manifest increased resistance against oxidative stress. Adult Sprague-Dawley rats were divided into seven groups. They drank sage or thyme extracts for 2 weeks. At the end of the drinking period, blood samples were collected for determination of liver biochemical parameters and hepatocytes were isolated to analyze (i) oxidatively generated DNA damage (conventional and modified comet assay), (ii) activities of antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPx)] and (iii) content of glutathione. Intake of sage and thyme had no effect either on the basal level of DNA damage or on the activity of SOD in rat hepatocytes and did not change the biochemical parameters of blood plasma. Simultaneously, the activity of GPx was significantly increased and the level of DNA damage induced by oxidants was decreased. Moreover, sage extract was able to start up the antioxidant protection expressed by increased content of glutathione. Our results indicate that the consumption of S.officinalis and T.vulgaris extracts positively affects resistency of rat liver cells against oxidative stress and may have hepatoprotective potential. PMID:26297740

  14. Bulk purification and deposition methods for selective enrichment in high aspect ratio single-walled carbon nanotubes.

    PubMed

    Bhatt, Nidhi P; Vichchulada, Pornnipa; Lay, Marcus D

    2012-06-01

    Aqueous batch processing methods for the concurrent purification of single-walled carbon nanotube (SWNT) soot and enrichment in high aspect ratio nanotubes are essential to their use in a wide variety of electronic, structural, and mechanical applications. This manuscript presents a new route to the bulk purification and enrichment of unbundled SWNTs having average lengths in excess of 2 μm. Iterative centrifugation cycles at low centripetal force not only removed amorphous C and catalyst nanoparticles but also allowed the enhanced buoyancy of surfactant encapsulated, unbundled, high aspect ratio SWNTs to be used to isolate them in the supernatant. UV-vis-NIR and Raman spectroscopy were used to verify the removal of residual impurities from as-produced (AP-grade) arc discharge soot and the simultaneous enrichment in unbundled, undamaged, high aspect ratio SWNTs. The laminar flow deposition process (LFD) used to form two-dimensional networks of SWNTs prevented bundle formation during network growth. Additionally, it further enhanced the quality of deposits by taking advantage of the inverse relationship between the translational diffusion coefficient and length for suspended nanoparticles. This resulted in preferential deposition of pristine, unbundled, high aspect ratio SWNTs over residual impurities, as observed by Raman spectroscopy and atomic force microscopy (AFM). PMID:22571337

  15. Aptamer-functionalized stir bar sorptive extraction coupled with gas chromatography-mass spectrometry for selective enrichment and determination of polychlorinated biphenyls in fish samples.

    PubMed

    Lin, Saichai; Gan, Ning; Zhang, Jiabin; Qiao, Li; Chen, Yinji; Cao, Yuting

    2016-03-01

    In this paper, a novel aptamer-functionalized stir bar sorptive extraction (SBSE) was developed for selective enrichment of the low abundance polychlorinated biphenyls (PCBs) from fish samples. This approach was based on the immobilization of aptamer which could recognize 2,3',5,5'-tetrachlorobiphenyl (PCB72) and 2',3',4',5,5'-pentachlorobiphenyl (PCB106) on one kind of metal-organic frameworks (Zn4O(BDC)3, MOF-5). MOF-5 as a substrate was prepared by potential-controlled cathodic electrodeposition on stainless steel. This aptamer-functionalized stir bar sorptive extraction (Apt-MOF SBSE) fiber could be facile synthesized in one-step. PCB72 and PCB106 were employed as target analytes for selective extraction by the developed method. The adsorbed targets could be desorbed easily in pH 3.0 100mM glycine-HCl buffers and then extracted by the methylene chloride. Afterwards, the detection was carried out with gas chromatography-tandem mass spectrometry (GC-MS). The Apt-MOF SBSE pretreatment coupled with GC-MS exhibited high selectivity, good binding capacity, stability and reproducibility for the detection of PCBs. It provided a linear range of 0.02-250ngmL(-1) with a good coefficient of determination (R(2)=0.9991-0.9996) and the detection limit was 0.003-0.004ngmL(-1). More importantly, the method was successfully utilized for the determination of PCBs in fish samples with good enrichment factor (1930-2304). Therefore, this new SBSE coating opens up the possibility of selective enrichment of a given target PCBs from complex fish samples. PMID:26717840

  16. A Diagnostic Approach to Increase Reusable Dinnerware Selection in a Cafeteria

    ERIC Educational Resources Information Center

    Manuel, Jennifer C.; Sunseri, Mary Anne; Olson, Ryan; Scolari, Miranda

    2007-01-01

    The current project tested a diagnostic approach to selecting interventions to increase patron selection of reusable dinnerware in a cafeteria. An assessment survey, completed by a sample of 43 patrons, suggested that the primary causes of wasteful behavior were (a) environmental arrangement of dinnerware options and (b) competing motivational…

  17. Impact of selection for increased daughter fertility on productive life and culling for reproduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Selection for increased daughter pregnancy rate (DPR) over 2 generations was examined to determine if such selection had affected cow fertility and productive life (PL). Holstein artificial-insemination bulls with a predicted transmitting ability (PTA) for DPR based on >=35 daughters were grouped by...

  18. Exploring mechanisms of survival in rainbow trout selectively bred for increased resistance to Flavobacterium psychrophilum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A challenge for selective breeding programs is to better understand how artificial selection alters host pathophysiologic and immunologic response following pathogen exposure. The National Center for Cool and Cold Water Aquaculture is exploring this in rainbow trout bred for increased survival (ARS...

  19. Selection for increased pheromone response in the male pink bollworm, Pectinophora gossypiella (Lepidoptera: Gelechiidae).

    PubMed

    Collins, R D; Cardé, R T

    1990-03-01

    The genetic basis of the duration and incidence of male wing fanning to pheromone in the pink bollworm moth, Pectinophora gossypiella (Saunders), was examined by artificial selection. Using a still-air bioassay, males from a laboratory colony were selected for increased duration of wing fanning when exposed to a 65:35 blend of (Z,E)- and (Z,Z)-7,11-hexadecadienyl acetates. The mean (+/- SE) duration of wing fanning in the selected line increased from 5.4 +/- 1.4 to 17.4 +/- 2.7 s after six generations. The increase in wing fanning duration was the result of an increase in response duration among responders and not the percentage of males that responded. Realized heritability of wing-fanning duration was 0.16 +/- 0.02. The amount and ratio of pheromone produced by females in the male-selected line did not change. PMID:2353914

  20. Rapid Response to Selection, Competitive Release and Increased Transmission Potential of Artesunate-Selected Plasmodium chabaudi Malaria Parasites

    PubMed Central

    Pollitt, Laura C.; Huijben, Silvie; Sim, Derek G.; Salathé, Rahel M.; Jones, Matthew J.; Read, Andrew F.

    2014-01-01

    The evolution of drug resistance, a key challenge for our ability to treat and control infections, depends on two processes: de-novo resistance mutations, and the selection for and spread of resistant mutants within a population. Understanding the factors influencing the rates of these two processes is essential for maximizing the useful lifespan of drugs and, therefore, effective disease control. For malaria parasites, artemisinin-based drugs are the frontline weapons in the fight against disease, but reports from the field of slower parasite clearance rates during drug treatment are generating concern that the useful lifespan of these drugs may be limited. Whether slower clearance rates represent true resistance, and how this provides a selective advantage for parasites is uncertain. Here, we show that Plasmodium chabaudi malaria parasites selected for resistance to artesunate (an artemisinin derivative) through a step-wise increase in drug dose evolved slower clearance rates extremely rapidly. In single infections, these slower clearance rates, similar to those seen in the field, provided fitness advantages to the parasite through increased overall density, recrudescence after treatment and increased transmission potential. In mixed infections, removal of susceptible parasites by drug treatment led to substantial increases in the densities and transmission potential of resistant parasites (competitive release). Our results demonstrate the double-edged sword for resistance management: in our initial selection experiments, no parasites survived aggressive chemotherapy, but after selection, the fitness advantage for resistant parasites was greatest at high drug doses. Aggressive treatment of mixed infections resulted in resistant parasites dominating the pool of gametocytes, without providing additional health benefits to hosts. Slower clearance rates can evolve rapidly and can provide a strong fitness advantage during drug treatment in both single and mixed strain

  1. Rapid response to selection, competitive release and increased transmission potential of artesunate-selected Plasmodium chabaudi malaria parasites.

    PubMed

    Pollitt, Laura C; Huijben, Silvie; Sim, Derek G; Salathé, Rahel M; Jones, Matthew J; Read, Andrew F

    2014-04-01

    The evolution of drug resistance, a key challenge for our ability to treat and control infections, depends on two processes: de-novo resistance mutations, and the selection for and spread of resistant mutants within a population. Understanding the factors influencing the rates of these two processes is essential for maximizing the useful lifespan of drugs and, therefore, effective disease control. For malaria parasites, artemisinin-based drugs are the frontline weapons in the fight against disease, but reports from the field of slower parasite clearance rates during drug treatment are generating concern that the useful lifespan of these drugs may be limited. Whether slower clearance rates represent true resistance, and how this provides a selective advantage for parasites is uncertain. Here, we show that Plasmodium chabaudi malaria parasites selected for resistance to artesunate (an artemisinin derivative) through a step-wise increase in drug dose evolved slower clearance rates extremely rapidly. In single infections, these slower clearance rates, similar to those seen in the field, provided fitness advantages to the parasite through increased overall density, recrudescence after treatment and increased transmission potential. In mixed infections, removal of susceptible parasites by drug treatment led to substantial increases in the densities and transmission potential of resistant parasites (competitive release). Our results demonstrate the double-edged sword for resistance management: in our initial selection experiments, no parasites survived aggressive chemotherapy, but after selection, the fitness advantage for resistant parasites was greatest at high drug doses. Aggressive treatment of mixed infections resulted in resistant parasites dominating the pool of gametocytes, without providing additional health benefits to hosts. Slower clearance rates can evolve rapidly and can provide a strong fitness advantage during drug treatment in both single and mixed strain

  2. Does selection on increased cold tolerance in the adult stage confer resistance throughout development?

    PubMed

    Dierks, A; Kölzow, N; Franke, K; Fischer, K

    2012-08-01

    Artificial selection is a powerful approach to unravel constraints on genetic adaptation. Although it has been frequently used to reveal genetic trade-offs among different fitness-related traits, only a few studies have targeted genetic correlations across developmental stages. Here, we test whether selection on increased cold tolerance in the adult stage increases cold resistance throughout ontogeny in the butterfly Bicyclus anynana. We used lines selected for decreased chill-coma recovery time and corresponding controls, which had originally been set up from three levels of inbreeding (outbred control, one or two full-sib matings). Four generations after having terminated selection, a response to selection was found in 1-day-old butterflies (the age at which selection took place). Older adults showed a very similar although weaker response. Nevertheless, cold resistance did not increase in either egg, larval or pupal stage in the selection lines but was even lower compared to control lines for eggs and young larvae. These findings suggest a cost of increased adult cold tolerance, presumably reducing resource availability for offspring provisioning and thereby stress tolerance during development, which may substantially affect evolutionary trajectories. PMID:22686583

  3. Selective enrichment and determination of monoamine neurotransmitters by CU(II) immobilized magnetic solid phase extraction coupled with high-performance liquid chromatography-fluorescence detection.

    PubMed

    He, Maofang; Wang, Chaozhan; Wei, Yinmao

    2016-01-15

    In this paper, iminodiacetic acid-Cu(II) functionalized Fe3O4@SiO2 magnetic nanoparticles were prepared and used as new adsorbents for magnetic solid phase extraction (MSPE) of six monoamine neurotransmitters (MNTs) from rabbit plasma. The selective enrichment of MNTs at pH 5.0 was motivated by the specific coordination interaction between amino groups of MNTs and the immobilized Cu(II). The employed weak acidic extraction condition avoided the oxidation of MNTs, and thus facilitated operation and ensured higher recoveries. Under optimal conditions, the recoveries of six MNTs from rabbit plasma were in the range of 83.9-109.4%, with RSD of 2.0-10.0%. When coupled the Cu(II) immobilized MSPE with high-performance liquid chromatography-fluorescence detection, the method exhibited relatively lower detection limits than the previously reported methods, and the method was successfully used to determine the endogenous MNTs in rabbit plasma. The proposed method has potential application for the determination of MNTs in biological samples. Also, the utilization of coordination interaction to improve the selectivity might open another way to selectively enrich small alkaloids from complex samples. PMID:26592630

  4. A Ti(4+)-immobilized phosphate polymer-patterned silicon substrate for on-plate selective enrichment and self-desalting of phosphopeptides.

    PubMed

    Xu, Lei; Zhu, Wei; Sun, Rui; Ding, Yin

    2015-05-01

    A circular hydrophobic-hydrophilic-Ti(4+) immobilized phosphate polymer is patterned on a silicon wafer. Such a wafer is used as a novel sample support to allow fast selective enrichment, wash-free self-desalting and mass spectroscopy (MS) analysis of phosphopeptides, thanks to the high Ti(4+) loading amount, pure phosphate polymer-Ti(4+) interface, and strong hydrophobic-hydrophilic attraction pattern. The detection sensitivity was enhanced 300 folds compared with what was obtained using the common MALDI plate. Remarkable selectivity for phosphopeptides can be achieved at a molar ratio as low as 1 : 500 of phosphopeptides (casein digest)/nonphosphopeptides (BSA). High-quality mass spectra can be obtained even in the presence of NaCl (1 M), NH4HCO3 (100 mM), or urea (1 M). These microspots were also used to selectively capture phosphopeptides from milk and human serum, which further demonstrated that they were capable of identifying low-abundance phosphopeptides from real complex samples. They provide a low detection limit (3 fmol μL(-1)), small sample size, and excellent enrichment and desalting efficiency. Such a method significantly simplifies the analytical procedures, reduces possible sample loss, and is relatively low cost. Therefore, this on-plate patterned technique is very promising in the high-throughput phosphoproteomic research, especially for the detection of tiny amounts of samples. PMID:25788104

  5. Detection of Campylobacter jejuni added to foods by using a combined selective enrichment and nucleic acid sequence-based amplification (NASBA).

    PubMed Central

    Uyttendaele, M; Schukkink, R; van Gemen, B; Debevere, J

    1995-01-01

    An assay to detect Campylobacter jejuni in foods that uses a short selective enrichment culture, a simple and rapid isolation procedure, NASBA amplification of RNA, and a nonradioactive in solution hybridization was studied. The presence of high numbers of indigenous flora affected the sensitivity of the assay. However, detection of C. jejuni was possible up to a ratio of indigenous flora to C. jejuni of 10,000:1. Interference by food components was eliminated by centrifugation following the enrichment step. Fourteen food samples artificially inoculated with C. jejuni (1 to 1,000 CFU/10 g) were analyzed with the NASBA assay and the conventional culture method with Campylobacter charcoal differential agar (CCDA). A few false-negative results were obtained by both NASBA (1.42%) and CCDA (2.86%) isolation. Yet the use of enrichment culture and NASBA shortened the analysis time from 6 days to 26 h. The relative simplicity and rapidity of the NASBA assay make it an attractive alternative for detection of C. jejuni in food samples. PMID:7747955

  6. Predation selects for increased immune function in male damselflies, Calopteryx splendens

    PubMed Central

    Rantala, Markus J.; Honkavaara, Johanna; Dunn, Derek W.; Suhonen, Jukka

    2011-01-01

    Predation selects for numerous traits in many animal species, with sick or parasitized prey often being at high risk. When challenged by parasites and pathogens, prey with poor immune functions are thus likely to be at a selective disadvantage. We tested the hypothesis that predation by birds selects for increased immune function in a wild population of male damselflies Calopteryx splendens, while controlling for a trait known to be under selection by bird predation, dark wing-spots. We found that selection on both immune function and wing-spot size was significantly positive, and that selection on either trait was independent of selection on the other. We found no evidence of nonlinear quadratic or correlational selection. In contrast to previous studies, we found no phenotypic correlation between immune function and wing-spot size. There was also no difference in immune response between territorial and non-territorial males. Our study suggests that predation may be an important agent of selection on the immune systems of prey, and because the selection we detected was directional, has the potential to cause phenotypic change in populations. PMID:20943692

  7. Boronic acid-functionalized core-shell-shell magnetic composite microspheres for the selective enrichment of glycoprotein.

    PubMed

    Pan, Miaorong; Sun, Yangfei; Zheng, Jin; Yang, Wuli

    2013-09-11

    In this work, core-shell-shell-structured boronic acid-functionalized magnetic composite microspheres Fe3O4@SiO2@poly (methyl methacrylate-co-4-vinylphenylbornoic acid) (Fe3O4@SiO2@P(MMA-co-VPBA)) with a uniform size and fine morphology were synthesized. Here, Fe3O4 magnetic particles were prepared by a solvothermal reaction, whereas the Fe3O4@SiO2 microspheres with a core-shell structure were obtained by a sol-gel process. 3-(Trimethoxysilyl) propyl methacrylate (MPS)-modified Fe3O4@SiO2 was used as the seed in the emulsion polymerization of MMA and VPBA to form the core-shell-shell-structured magnetic composite microspheres. As the boronic acid groups on the surface of Fe3O4@SiO2@P(MMA-co-VPBA) could form tight yet reversible covalent bonds with the cis-1,2-diols groups of glycoproteins, the magnetic composite microspheres were applied to enrich a standard glycoprotein, horseradish peroxidase (HRP), and the results demonstrated that the composite microspheres have a higher affinity for the glycoproteins in the presence of the nonglycoprotein bovine serum albumin (BSA) over HRP. Additionally, different monomer mole ratios of MMA/VPBA were studied, and the results implied that using MMA as the major monomer could reduce the amount of VPBA with a similar glycoprotein enrichment efficiency but a lower cost. PMID:23924282

  8. Small prizes increased healthful school lunch selection in a Midwestern school district.

    PubMed

    Siegel, Robert; Lockhart, Mary Kate; Barnes, Allison S; Hiller, Elizabeth; Kipp, Roger; Robison, Debora L; Ellsworth, Samantha C; Hudgens, Michelle E

    2016-04-01

    As obesity has become a pressing health issue for American children, greater attention has been focused on how schools can be used to improve how students eat. Previously, we piloted the use of small prizes in an elementary school cafeteria to improve healthful food selection. We hoped to increase healthful food selection in all the elementary schools of a small school district participating in the United States Department of Agriculture Lunch Program by offering prizes to children who selected a Power Plate (PP), which consisted of an entrée with whole grains, a fruit, a vegetable, and plain low-fat milk. In this study, the PP program was introduced to 3 schools sequentially over an academic year. During the kickoff week, green, smiley-faced emoticons were placed by preferred foods, and children were given a prize daily if they chose a PP on that day. After the first week, students were given a sticker or temporary tattoo 2 days a week if they selected a PP. Combining data from the 3 schools in the program, students increased PP selection from 4.5% at baseline to 49.4% (p < 0.0001) during an intervention period of 2.5 school weeks. The school with the longest intervention period, 6 months, showed a PP selection increase of from 3.9% to 26.4% (p < 0.0001). In conclusion, giving small prizes as rewards dramatically improves short-term healthful food selection in elementary school children. PMID:26914228

  9. Leukocyte numbers and function in subjects eating n-3 enriched foods: selective depression of natural killer cell levels

    PubMed Central

    Mukaro, Violet R; Costabile, Maurizio; Murphy, Karen J; Hii, Charles S; Howe, Peter R; Ferrante, Antonio

    2008-01-01

    Introduction While consumption of omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) has been recommended for those at risk of inflammatory disease such as rheumatoid arthritis, the mechanism of their anti-inflammatory effect remains to be clearly defined, particularly in relation to the dose and type of n-3 LCPUFA. The objective of this study was to determine whether varying the levels of n-3 LCPUFA in erythrocyte membrane lipids, following dietary supplementation, is associated with altered numbers and function of circulating leukocytes conducive to protection against inflammation. Methods In a double-blind and placebo-controlled study, 44 healthy subjects aged 23 to 63 years consumed either standard or n-3 LCPUFA-enriched versions of typical processed foods, the latter allowing a target daily consumption of 1 gram n-3 LCPUFA. After six months, peripheral blood leukocyte and subpopulation proportions and numbers were assessed by flow cytometry. Leukocytes were also examined for lymphoproliferation and cytokine production, neutrophil chemotaxis, chemokinesis, bactericidal, adherence and iodination activity. Erythrocytes were analyzed for fatty-acid content. Results Erythrocyte n-3 LCPUFA levels were higher and absolute leukocyte and lymphocyte numbers were lower in subjects consuming n-3 enriched foods than in controls. There were no changes in the number of neutrophils, monocytes, T cells (CD3+), T-cell subsets (CD4+, CD8+) and B cells (CD19+). However, natural killer (NK) (CD3-CD16+CD56+) cell numbers were lower in n-3 supplemented subjects than in controls and were inversely related to the amount of eicosapentaenoic acid or docosahexaenoic acid in erythrocytes. No significant correlations were found with respect to lymphocyte lymphoproliferation and production of IFN-γ and IL-2, but lymphotoxin production was higher with greater n-3 LCPUFA membrane content. Similarly, neutrophil chemotaxis, chemokinesis, bactericidal activity and adherence did not

  10. Label-free selection and enrichment of liver cancer stem cells by surface niches build up with polyelectrolyte multilayer films.

    PubMed

    Lee, I-Chi; Chang, Jen-Fu

    2015-01-01

    Recent studies indicate that a small population of cancer cells exhibits stem cell properties and are referred to as cancer-initiating or cancer stem cells (CSCs). The selection and identification of cancer stem cells through methods require well-defined biomarkers and immunolabeling procedures are complicated and often unreliable. Herein, we fabricated a series of microenviroment by using polyelectrolyte multilayers (PEM) nanofilms to program and mimic hepatocellular carcinoma CSCs niches for CSCs selection with a label-free method. When cultured on PEM substrates, human cancer cell lines-Huh7 cells grew into individual round colonies and these cells displayed high marker expression of CSCs. Especially, these selected cells demonstrated significant chemo-resistant property in comparison with normal population. Therefore, we believed that niches selection and colony formation method may provide a new strategy on CSCs selection and drug evaluation for cancer therapy. PMID:25461919

  11. Preparation of Ti(4+)-immobilized modified silica capillary trapping column for on-line selective enrichment of phosphopeptides.

    PubMed

    Yang, Huili; Deng, Chunhui; Zhang, Xiangmin

    2016-06-01

    In this work, we have developed Ti(4+)-immobilized capillary trapping column (250μm i.d.) for highly specific on-line enrichment of phosphopeptides in the bio-samples. It minimizes the sample loss and improves the effectiveness of phosphopeptide detection that the limit of detection is as low as 1fmol/μL. It is successfully applied to the detection of phosphopeptides from complex biological samples, such as skim milk, human serum and mouse brain. The results indicate that the Ti(4+)-immobilized capillary trapping column is time-effective and has the great potential of application in low-abundance phosphopeptides on-line analysis. The prepared Ti(4+)-immobilized capillary trapping column will be further used in LC/MS platform for phosphoproteome analysis. PMID:27130120

  12. Increased DHT levels in androgenic alopecia have been selected for to protect men from prostate cancer.

    PubMed

    Bhargava, Shiva

    2014-04-01

    Androgenic alopecia, a condition characterized by increased levels of DHT could have been selected for due to the benefits that prostaglandin D2 (PGD(2)) has on the prostate. A DHT metabolite can increase the transcription of prostaglandin D2 synthase through estrogen receptor beta. The increase of PGD(2) can decrease the risk of prostate cancer and proliferation of prostate cancer cells. Therefore, the mechanisms behind male pattern baldness may also curtail the advancement of prostate cancer. PMID:24548754

  13. Selective Enrichment and MALDI-TOF MS Analysis of Small Molecule Compounds with Vicinal Diols by Boric Acid-Functionalized Graphene Oxide

    NASA Astrophysics Data System (ADS)

    Zhang, Jing; Zheng, Xiaoling; Ni, Yanli

    2015-08-01

    In this study, a 4-vinylphenylboronic acid-functionalized graphene oxide (GO) material was prepared via atom-transfer radical polymerization (ATRP) method and applied for the first time as a novel matrix for the selective enrichment and analysis of small-molecule compounds with vicinal diols, which have been the focus of intense research in the field of life science, by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) in positive-ion mode. There are two main factors playing a decisive role in assisting laser D/I process comparing to some traditional matrices: (1) GO provides π-conjugated system by itself for laser absorption and energy transfer; (2) the modified 4-vinylphenylboronic acid can selectively capture small-molecule compounds with vicinal diols. The results demonstrate that the novel material has distinct advantages over previously reported matrices in enriching and assisting the highly efficient ionization of target molecules for mass spectrometry analysis. This work indicates a new application branch for graphene-based matrices and provides an alternative solution for small-molecules analysis.

  14. Novel polyazamacrocyclic receptor decorated core-shell superparamagnetic microspheres for selective binding and magnetic enrichment of palladium: synthesis, adsorptive behavior and coordination mechanism.

    PubMed

    Wu, Fengcheng; Ye, Gang; Yi, Rong; Sun, Taoxiang; Xu, Chao; Chen, Jing

    2016-06-21

    The development of economical and green technologies for the effective recovery of palladium has attracted worldwide attention in recent years. Magnetic separation involving the use of functional magnetic nanoparticles (MNPs) with superparamagnetic characteristics holds great promise in this respect. This study presents a novel class of core-shell structured superparamagnetic microspheres decorated with polyazamacrocyclic receptors, which show a highly-selective binding to Pd(ii) in HNO3 media. The superparamagnetic microspheres possess a high saturation magnetization (53.8 emu g(-1)) and high adsorption capacity (qmax≈ 105.3 μmol g(-1)), affording efficient enrichment and fast separation (within 13 seconds) of palladium under an applied magnetic field. Adsorptive behavior was fully investigated combined with the corresponding theoretical analysis by using kinetic equations and Langmuir/Freundlich isotherm models. Moreover, the coordination mechanism of the polyazamacrocyclic receptors to Pd(ii) was carefully examined based on high resolution X-ray photoelectron spectroscopy (XPS) and FT-IR spectrophotometry. A suggested mechanism involving the synergistic effect of the cyclic amines and carboxyl arms of the polyazamacrocyclic receptors was proposed to describe the coordination manner, while explaining the selectivity to Pd(ii) in HNO3 solutions. From a practical perspective, the Pd(ii)-enriched microspheres could be readily regenerated for cycle use. We conclude that this kind of polyazamacrocyclic receptor decorated superparamagnetic microsphere is of potential use for the effective recovery of Pd(ii) as well as other precious metals. PMID:27197846

  15. Metal-organic frameworks@graphene hybrid aerogels for solid-phase extraction of non-steroidal anti-inflammatory drugs and selective enrichment of proteins.

    PubMed

    Zhang, Xiaoqiong; Liang, Qionglin; Han, Qiang; Wan, Wei; Ding, Mingyu

    2016-06-20

    Graphene aerogel (GA)-supported metal-organic framework (MOF) particles with a three-dimensional (3D) architecture were fabricated for the first time via a facile template-free "sol-cryo" method. The prepared MOFs@graphene hybrid aerogels exhibit a 3D interconnected macroporous framework of graphene sheets with uniform dispersion of MOF particles. We also report the first attempt at using the hybrid aerogels as adsorbents for the solid-phase extraction (SPE) of non-steroidal anti-inflammatory drugs (NSAIDs) and the selective enrichment of proteins. The macroporous skeletons of GA provide both low backpressure and rapid mass transfer in SPE application, thus overcoming the obstacle of high backpressure caused by directly packing submicron or micron sized MOF particles into SPE cartridges. Excellent performances including satisfactory recoveries, high sensitivity and good reproducibility were achieved in the extraction of five NSAIDs. The hybrid aerogels also showed an interesting ability for selective enrichment of ribonuclease A (RNase A) and simultaneous exclusion of cytochrome C (Cyt C) and lysozyme (Lyz), which could be attributed to the electrostatic interactions between proteins and the positively charged coordinatively unsaturated metal sites (CUS) in MIL-101. We believe that this work will promote the application of MOFs in adsorption and separation, and our synthetic strategy could be further extended to develop other graphene-based hybrid aerogels. PMID:27156534

  16. Selective Enrichment and MALDI-TOF MS Analysis of Small Molecule Compounds with Vicinal Diols by Boric Acid-Functionalized Graphene Oxide.

    PubMed

    Zhang, Jing; Zheng, Xiaoling; Ni, Yanli

    2015-08-01

    In this study, a 4-vinylphenylboronic acid-functionalized graphene oxide (GO) material was prepared via atom-transfer radical polymerization (ATRP) method and applied for the first time as a novel matrix for the selective enrichment and analysis of small-molecule compounds with vicinal diols, which have been the focus of intense research in the field of life science, by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) in positive-ion mode. There are two main factors playing a decisive role in assisting laser D/I process comparing to some traditional matrices: (1) GO provides π-conjugated system by itself for laser absorption and energy transfer; (2) the modified 4-vinylphenylboronic acid can selectively capture small-molecule compounds with vicinal diols. The results demonstrate that the novel material has distinct advantages over previously reported matrices in enriching and assisting the highly efficient ionization of target molecules for mass spectrometry analysis. This work indicates a new application branch for graphene-based matrices and provides an alternative solution for small-molecules analysis. PMID:25990923

  17. Enriched Astaxanthin Extract from Haematococcus pluvialis Augments Growth Factor Secretions to Increase Cell Proliferation and Induces MMP1 Degradation to Enhance Collagen Production in Human Dermal Fibroblasts

    PubMed Central

    Chou, Hsin-Yu; Lee, Chelsea; Pan, Jian-Liang; Wen, Zhi-Hong; Huang, Shu-Hung; Lan, Chi-Wei John; Liu, Wang-Ta; Hour, Tzyh-Chyuan; Hseu, You-Cheng; Hwang, Byeong Hee; Cheng, Kuo-Chen; Wang, Hui-Min David

    2016-01-01

    Among many antioxidants that are used for the repairing of oxidative stress induced skin damages, we identified the enriched astaxanthin extract (EAE) from Haematococcus pluvialis as a viable ingredient. EAE was extracted from the red microalgae through supercritical fluid carbon dioxide extraction. To compare the effectiveness, EAE wastreated on human dermal fibroblasts with other components, phorbol 12-myristate 13-acetate (PMA), and doxycycline. With sirius red staining and quantitative real-time polymerase chain reaction (qRT-PCR), we found that PMA decreased the collagen concentration and production while overall the addition of doxycycline and EAE increased the collagen concentration in a trial experiments. EAE increased collagen contents through inhibited MMP1 and MMP3 mRNA expression and induced TIMP1, the antagonists of MMPs protein, gene expression. As for when tested for various proteins through western blotting, it was seen that the addition of EAE increased the expression of certain proteins that promote cell proliferation. Testing those previous solutions using growth factor assay, it was noticeable that EAE had a positive impact on cell proliferation and vascular endothelial growth factor (VEGF) than doxycycline, indicating that it was a better alternative treatment for collagen production. To sum up, the data confirmed the possible applications as medical cosmetology agentsand food supplements. PMID:27322248

  18. Enriched Astaxanthin Extract from Haematococcus pluvialis Augments Growth Factor Secretions to Increase Cell Proliferation and Induces MMP1 Degradation to Enhance Collagen Production in Human Dermal Fibroblasts.

    PubMed

    Chou, Hsin-Yu; Lee, Chelsea; Pan, Jian-Liang; Wen, Zhi-Hong; Huang, Shu-Hung; Lan, Chi-Wei John; Liu, Wang-Ta; Hour, Tzyh-Chyuan; Hseu, You-Cheng; Hwang, Byeong Hee; Cheng, Kuo-Chen; Wang, Hui-Min David

    2016-01-01

    Among many antioxidants that are used for the repairing of oxidative stress induced skin damages, we identified the enriched astaxanthin extract (EAE) from Haematococcus pluvialis as a viable ingredient. EAE was extracted from the red microalgae through supercritical fluid carbon dioxide extraction. To compare the effectiveness, EAE wastreated on human dermal fibroblasts with other components, phorbol 12-myristate 13-acetate (PMA), and doxycycline. With sirius red staining and quantitative real-time polymerase chain reaction (qRT-PCR), we found that PMA decreased the collagen concentration and production while overall the addition of doxycycline and EAE increased the collagen concentration in a trial experiments. EAE increased collagen contents through inhibited MMP1 and MMP3 mRNA expression and induced TIMP1, the antagonists of MMPs protein, gene expression. As for when tested for various proteins through western blotting, it was seen that the addition of EAE increased the expression of certain proteins that promote cell proliferation. Testing those previous solutions using growth factor assay, it was noticeable that EAE had a positive impact on cell proliferation and vascular endothelial growth factor (VEGF) than doxycycline, indicating that it was a better alternative treatment for collagen production. To sum up, the data confirmed the possible applications as medical cosmetology agentsand food supplements. PMID:27322248

  19. SELECTIVE TRACE ENRICHMENT BY IMMUNOAFFINITY CAPILLARY ELECTROCHROMATOGRAPHY ON-LINE WITH CAPILLARY ZONE ELECTROPHORESIS - LASER-INDUCED FLUORESCENCE

    EPA Science Inventory

    Limited by the lack of a sensitive, universal detector, many capillary-based liquid-phase separation techniques might benefit from techniques that overcome modest concentration sensitivity by preconcentrating large injection volumes. The work presented employs selective solid-ph...

  20. Sexual selection in true fruit flies (Diptera: Tephritidae): transcriptome and experimental evidences for phytochemicals increasing male competitive ability.

    PubMed

    Kumaran, Nagalingam; Prentis, Peter J; Mangalam, Kalimuthu P; Schutze, Mark K; Clarke, Anthony R

    2014-09-01

    In male tephritid fruit flies of the genus Bactrocera, feeding on secondary plant compounds (sensu lato male lures = methyl eugenol, raspberry ketone and zingerone) increases male mating success. Ingested male lures alter the male pheromonal blend, normally making it more attractive to females and this is considered the primary mechanism for the enhanced mating success. However, the male lures raspberry ketone and zingerone are known, across a diverse range of other organisms, to be involved in increasing energy metabolism. If this also occurs in Bactrocera, then this may represent an additional benefit to males as courtship is metabolically expensive and lure feeding may increase a fly's short-term energy. We tested this hypothesis by performing comparative RNA-seq analysis between zingerone-fed and unfed males of Bactrocera tryoni. We also carried out behavioural assays with zingerone- and cuelure-fed males to test whether they became more active. RNA-seq analysis revealed, in zingerone-fed flies, up-regulation of 3183 genes with homologues transcripts to those known to regulate intermale aggression, pheromone synthesis, mating and accessory gland proteins, along with significant enrichment of several energy metabolic pathways and gene ontology terms. Behavioural assays show significant increases in locomotor activity, weight reduction and successful mating after mounting; all direct/indirect measures of increased activity. These results suggest that feeding on lures leads to complex physiological changes, which result in more competitive males. These results do not negate the pheromone effect, but do strongly suggest that the phytochemical-induced sexual selection is governed by both female preference and male competitive mechanisms. PMID:25112896

  1. The Proteome of Cholesteryl-Ester-Enriched Versus Triacylglycerol-Enriched Lipid Droplets

    PubMed Central

    Khor, Victor K.; Ahrends, Robert; Lin, Ye; Shen, Wen-Jun; Adams, Christopher M.; Roseman, Ann Nomoto; Cortez, Yuan; Teruel, Mary N.; Azhar, Salman; Kraemer, Fredric B.

    2014-01-01

    Within cells, lipids are stored in the form of lipid droplets (LDs), consisting of a neutral lipid core, surrounded by a phospholipid monolayer and an outer layer of protein. LDs typically accumulate either triacylglycerol (TAG) and diacylglycerol or cholesteryl ester (CE), depending on the type of tissue. Recently, there has been an increased interest in the proteins that surround LDs. LD proteins have been found to be quite diverse, from structural proteins to metabolic enzymes, proteins involved in vesicular transport, and proteins that may play a role in LD formation. Previous proteomics analyses have focused on TAG-enriched LDs, whereas CE-enriched LDs have been largely ignored. Our study has compared the LD proteins from CE-enriched LDs to TAG-enriched LDs in steroidogenic cells. In primary rat granulosa cells loaded with either HDL to produce CE-enriched LDs or fatty acids to produce TAG-enriched LDs, 61 proteins were found to be elevated in CE-enriched LDs and 40 proteins elevated in TAG-enriched LDs with 278 proteins in similar amounts. Protein expression was further validated by selected reaction monitoring (SRM) mass spectrometry (MS). SRM verified expression of 25 of 27 peptides that were previously detected by tandem mass tagging MS. Several proteins were confirmed to be elevated in CE-enriched LDs by SRM including the intermediate filament vimentin. This study is the first to compare the proteins found on CE-enriched LDs with TAG-enriched LDs and constitutes the first step in creating a better understanding of the proteins found on CE-enriched LDs in steroidogenic cells. PMID:25111084

  2. CUE (CULTURE, UNDERSTANDING, ENRICHMENT)--HOME ECONOMICS.

    ERIC Educational Resources Information Center

    BROWN, ROBERT M.; AND OTHERS

    THIS PUBLICATION IS A TEACHING GUIDE TO PROVIDE GUIDANCE FOR INTEGRATING CAREFULLY SELECTED AUDIOVISUAL ITEMS INTO EXISTING NINTH-GRADE CURRICULUMS IN HOME ECONOMICS. IT IS ONE OF FIVE GUIDES PREPARED FOR USE IN PROJECT CUE, AN EXPERIMENTAL PROGRAM DESIGNED TO INCREASE CULTURAL UNDERSTANDING AND ENRICHMENT IN THE EDUCATIONAL PROGRAMS OF HIGH…

  3. CUE (CULTURE, UNDERSTANDING, ENRICHMENT)--SCIENCE.

    ERIC Educational Resources Information Center

    BROWN, ROBERT M.; AND OTHERS

    THIS PUBLICATION IS A TEACHING GUIDE TO PROVIDE GUIDANCE FOR INTEGRATING CAREFULLY SELECTED AUDIOVISUAL ITEMS INTO EXISTING NINTH-GRADE CURRICULUMS IN SCIENCE. IT IS ONE OF FIVE GUIDES PREPARED FOR USE IN PROJECT CUE, AN EXPERIMENTAL PROGRAM DESIGNED TO INCREASE CULTURAL UNDERSTANDING AND ENRICHMENT IN THE EDUCATIONAL PROGRAMS OF HIGH SCHOOLS. THE…

  4. CUE (CULTURE, UNDERSTANDING, ENRICHMENT)--INDUSTRIAL ARTS.

    ERIC Educational Resources Information Center

    BROWN, ROBERT M.; AND OTHERS

    THIS PUBLICATION IS A TEACHING GUIDE TO PROVIDE GUIDANCE FOR INTEGRATING CAREFULLY SELECTED AUDIOVISUAL ITEMS INTO EXISTING NINTH-GRADE CURRICULUMS IN INDUSTRIAL ARTS. IT IS ONE OF FIVE GUIDES PREPARED FOR USE IN PROJECT CUE, AN EXPERIMENTAL PROGRAM DESIGNED TO INCREASE CULTURAL UNDERSTANDING AND ENRICHMENT IN THE EDUCATIONAL PROGRAMS OF HIGH…

  5. Unexpected but welcome. Artificially selected traits may increase fitness in wild boar.

    PubMed

    Fulgione, Domenico; Rippa, Daniela; Buglione, Maria; Trapanese, Martina; Petrelli, Simona; Maselli, Valeria

    2016-07-01

    Artificial selection affects phenotypes differently by natural selection. Domestic traits, which pass into the wild, are usually negatively selected. Yet, exceptionally, this axiom may fail to apply if genes, from the domestic animals, increase fertility in the wild. We studied a rare case of a wild boar population under the framework of Wright's interdemic selection model, which could explain gene flow between wild boar and pig, both considered as demes. We analysed the MC1R gene and microsatellite neutral loci in 62 pregnant wild boars as markers of hybridization, and we correlated nucleotide mutations on MC1R (which are common in domestic breeds) to litter size, as an evaluation of fitness in wild sow. Regardless of body size and phyletic effects, wild boar sows bearing nonsynonymous MC1R mutations produced larger litters. This directly suggests that artificially selected traits reaching wild populations, through interdemic gene flow, could bypass natural selection if and only if they increase the fitness in the wild. PMID:27330553

  6. Selective enrichment of metal-binding proteins based on magnetic core/shell microspheres functionalized with metal cations.

    PubMed

    Fang, Caiyun; Zhang, Lei; Zhang, Xiaoqin; Lu, Haojie

    2015-06-21

    Metal binding proteins play many important roles in a broad range of biological processes. Characterization of metal binding proteins is important for understanding their structure and biological functions, thus leading to a clear understanding of metal associated diseases. The present study is the first to investigate the effectiveness of magnetic microspheres functionalized with metal cations (Ca(2+), Cu(2+), Zn(2+) and Fe(3+)) as the absorbent matrix in IMAC technology to enrich metal containing/binding proteins. The putative metal binding proteins in rat liver were then globally characterized by using this strategy which is very easy to handle and can capture a number of metal binding proteins effectively. In total, 185 putative metal binding proteins were identified from rat liver including some known less abundant and membrane-bound metal binding proteins such as Plcg1, Acsl5, etc. The identified proteins are involved in many important processes including binding, catalytic activity, translation elongation factor activity, electron carrier activity, and so on. PMID:25913209

  7. Strong pollinator-mediated selection for increased flower brightness and contrast in a deceptive orchid.

    PubMed

    Sletvold, Nina; Trunschke, Judith; Smit, Mart; Verbeek, Jeffrey; Ågren, Jon

    2016-03-01

    Contrasting flower color patterns that putatively attract or direct pollinators toward a reward are common among angiosperms. In the deceptive orchid Anacamptis morio, the lower petal, which makes up most of the floral display, has a light central patch with dark markings. Within populations, there is pronounced variation in petal brightness, patch size, amount of dark markings, and contrast between patch and petal margin. We tested whether pollinators mediate selection on these color traits and on morphology (plant height, number of flowers, corolla size, spur length), and whether selection is consistent with facilitated or negative frequency-dependent pollination. Pollinators mediated strong selection for increased petal brightness (Δβpoll = 0.42) and contrast (Δβpoll = 0.51). Pollinators also tended to mediate stabilizing selection on brightness (Δγpoll = -0.27, n.s.) favoring the most common phenotype in the population. Selection for reduced petal brightness among hand-pollinated plants indicated a fitness cost associated with brightness. The results demonstrate that flower color traits influence pollination success and seed production in A. morio, indicating that they affect attractiveness to pollinators, efficiency of pollen transfer, or both. The documented selection is consistent with facilitated pollination and selection for color convergence toward cooccurring rewarding species. PMID:26878831

  8. Limb contribution to increased self-selected walking speeds during body weight support in individuals poststroke.

    PubMed

    Hurt, Christopher P; Burgess, Jamie K; Brown, David A

    2015-03-01

    Individuals poststroke walk at faster self-selected speeds under some nominal level of body weight support (BWS) whereas nonimpaired individuals walk slower after adding BWS. The purpose of this study was to determine whether increases in self-selected overground walking speed under BWS conditions of individuals poststroke can be explained by changes in their paretic and nonparetic ground reaction forces (GRF). We hypothesize that increased self-selected walking speed, recorded at some nominal level of BWS, will relate to decreased braking GRFs by the paretic limb. We recruited 10 chronic (>12 months post-ictus, 57.5±9.6 y.o.) individuals poststroke and eleven nonimpaired participants (53.3±4.1 y.o.). Participants walked overground in a robotic device, the KineAssist Walking and Balance Training System that provided varying degrees of BWS (0-20% in 5% increments) while individuals self-selected their walking speed. Self-selected walking speed and braking and propulsive GRF impulses were quantified. Out of 10 poststroke individuals, 8 increased their walking speed 13% (p=0.004) under some level of BWS (5% n=2, 10% n=3, 20% n=3) whereas nonimpaired controls did not change speed (p=0.470). In individuals poststroke, changes to self-selected walking speed were correlated with changes in paretic propulsive impulses (r=0.68, p=0.003) and nonparetic braking impulses (r=-0.80, p=0.006), but were not correlated with decreased paretic braking impulses (r=0.50 p=0.14). This investigation demonstrates that when individuals poststroke are provided with BWS and allowed to self-select their overground walking speed, they are capable of achieving faster speeds by modulating braking impulses on the nonparetic limb and propulsive impulses of the paretic limb. PMID:25770079

  9. Selection for pro-inflammatory mediators yields chickens with increased resistance against Salmonella enterica serovar Enteritidis.

    PubMed

    Swaggerty, Christina L; Pevzner, Igal Y; Kogut, Michael H

    2014-03-01

    Salmonella is a leading cause of foodborne illness and can be transmitted through consumption of contaminated poultry; therefore, increasing a flock's natural resistance to Salmonella could improve food safety. Previously, we characterized the heterophil-mediated innate immune response of 2 parental broiler lines and F1 reciprocal crosses and showed that increased heterophil function and expression of pro-inflammatory mediators corresponds with increased resistance against diverse pathogens. A preliminary selection trial showed that individual sires had varying inherent levels of pro-inflammatory mediators and selection based on a high or low phenotype was passed onto progeny. Based on these results, we hypothesized selection of broilers for higher levels of the pro-inflammatory mediators IL-6, CXCLi2, and CCLi2 would produce progeny with increased resistance against Salmonella Enteritidis. Peripheral blood leukocytes were isolated from 75 commercial broiler sires, screened, and 10 naturally high and low expressing sires were selected and mated to randomly selected dams to produce the first generation of "high" and "low" progeny. The mRNA expression of CXCLi2 and CCLi2 were significantly (P ≤ 0.02) higher in the high progeny and were more resistant to liver and spleen organ invasion by Salmonella Enteritidis compared with low progeny. Production of the second generation yielded progeny that had differences (P ≤ 0.03) in all 3 mediators and further improved resistance against Salmonella Enteritidis. Feed conversion ratio and percent breast meat yield were calculated and were equal, whereas the high birds weighed slightly, but significantly, less than the low birds. These data clearly demonstrate that selection based on a higher phenotype of key pro-inflammatory mediators is a novel means to produce broilers that are naturally more resistant to Salmonella, one of the most important foodborne pathogens affecting the poultry industry. PMID:24604845

  10. Preliminary field evaluation of rainbow trout selectively bred for increased resistance to bacterial cold water disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bacterial cold water disease (BCWD) is one of the most frequent causes of elevated mortality in juvenile salmonids, and the development of effective control strategies is a priority. We previously reported results of a selective breeding program designed to increase rainbow trout survival following ...

  11. Plant mortality and natural selection may increase biomass yield in switchgrass swards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Switchgrass (Panicum virgatum L.) is an important candidate for bioenergy feedstock production, prompting significant efforts to increase the number of breeding programs and the output of those programs. The objective of this experiment was to determine the potential utility of natural selection for...

  12. Field emergence and plant density of sand bluestem lines selected for increased seed germination.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sand bluestem (Andropogon hallii Hack.) populations AB-medium Syn-1 and Syn-2, and CD-tall Syn-1 and Syn-2 were developed from populations AB-medium Syn-0 and CD-tall Syn-0 by recurrent selection for increased seed germination in low water potentials. The objective of this research was to verify if...

  13. Environmental Enrichment Increases Glucocorticoid Receptors and Decreases GluA2 and Protein Kinase M Zeta (PKMζ) Trafficking During Chronic Stress: A Protective Mechanism?

    PubMed Central

    Zanca, Roseanna M.; Braren, Stephen H.; Maloney, Brigid; Schrott, Lisa M.; Luine, Victoria N.; Serrano, Peter A.

    2015-01-01

    Environmental enrichment (EE) housing paradigms have long been shown beneficial for brain function involving neural growth and activity, learning and memory capacity, and for developing stress resiliency. The expression of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluA2, which is important for synaptic plasticity and memory, is increased with corticosterone (CORT), undermining synaptic plasticity and memory. Thus, we determined the effect of EE and stress on modulating GluA2 expression in Sprague-Dawley male rats. Several markers were evaluated which include: plasma CORT, the glucocorticoid receptor (GR), GluA2, and the atypical protein kinase M zeta (PKMζ). For 1 week standard-(ST) or EE-housed animals were treated with one of the following four conditions: (1) no stress; (2) acute stress (forced swim test, FST; on day 7); (3) chronic restraint stress (6 h/day for 7 days); and (4) chronic + acute stress (restraint stress 6 h/day for 7 days + FST on day 7). Hippocampi were collected on day 7. Our results show that EE animals had reduced time immobile on the FST across all conditions. After chronic + acute stress EE animals showed increased GR levels with no change in synaptic GluA2/PKMζ. ST-housed animals showed the reverse pattern with decreased GR levels and a significant increase in synaptic GluA2/PKMζ. These results suggest that EE produces an adaptive response to chronic stress allowing for increased GR levels, which lowers neuronal excitability reducing GluA2/PKMζ trafficking. We discuss this EE adaptive response to stress as a potential underlying mechanism that is protective for retaining synaptic plasticity and memory function. PMID:26617502

  14. Mechanisms of H2S Production from Cysteine and Cystine by Microorganisms Isolated from Soil by Selective Enrichment

    PubMed Central

    Morra, Matthew J.; Dick, Warren A.

    1991-01-01

    Hydrogen sulfide (H2S) is a major component of biogenic gaseous sulfur emissions from terrestrial environments. However, little is known concerning the pathways for H2S production from the likely substrates, cysteine and cystine. A mixed microbial culture obtained from cystine-enriched soils was used in assays (50 min, 37°C) with 0.05 M Tris-HCl (pH 8.5), 25 μmol of l-cysteine, 25 μmol of l-cystine, and 0.04 μmol of pyridoxal 5′-phosphate. Sulfide was trapped in a center well containing zinc acetate, while pyruvate was measured by derivatization with 2,4-dinitrophenylhydrazine. Sulfide and total pyruvate production were 17.6 and 17.2 nmol mg of protein-1 min-1, respectively. Dithiothreitol did not alter reaction stoichiometry or the amount of H2S and total pyruvate, whereas N-ethylmaleimide reduced both H2S and total pyruvate production equally. The amount of H2S produced was reduced by 96% when only l-cystine was included as the substrate in the assay and by 15% with the addition of propargylglycine, a specific suicide inhibitor of cystathionine γ-lyase. These data indicate that the substrate for the reaction was cysteine and the enzyme responsible for H2S and pyruvate production was cysteine desulfhydrase (EC 4.4.1.1). The enzyme had a Km of 1.32 mM and was inactivated by temperatures greater than 60°C. Because cysteine is present in soil and cysteine desulfhydrase is an inducible enzyme, the potential for H2S production by this mechanism exists in terrestrial environments. The relative importance of this mechanism compared with other processes involved in H2S production from soil is unknown. PMID:16348483

  15. Mechanisms of H sub 2 S production from cysteine and cystine by microorganisms isolated from soil by selective enrichment

    SciTech Connect

    Morra, M.J.; Dick, W.A. )

    1991-05-01

    Hydrogen sulfide (H{sub 2}S) is a major component of biogenic gaseous sulfur emissions from terrestrial environments. However, little is known concerning the pathways for H{sub 2}S production from the likely substrates, cysteine and cystine. A mixed microbial culture obtained from Cystine-enriched soils was used in assays (50 min, 37C) with 0.05 M Tris-HCI (pH 8.5), 25 {mu}mol of L-cysteine, 25 {mu}mol of L-cystine, and 0.04 {mu}mol of pyridoxal 5 feet-phosphate. Sulfide and total pyruvate production were 17.6 and 17.2 nmol mg of protein{sup {minus}1} min{sup {minus}1}, respectively. Dithiothreitol did not alter reaction stoichiometry or the amount of H{sub 2}S and total pyruvate, whereas N-ethylmaleimide reduced both H{sub 2}S and total pyruvate production in the assay and by 15% with the addition of propargylglycine, a specific suicide inhibitor of cystathionine {gamma}-lyase. These data indicate that the substrate for the reaction was cysteine and the enzyme responsible for H{sub 2}S and pyruvate production was cysteine desulfhydrase. The enzyme had a K{sub m} of 1.32 mM and was inactivated by temperatures greater that 60C. Because cysteine is present in soil and cysteine desulfhydrase is an inducible enzyme, the potential for H{sub 2}S production by this mechanism exists in terrestrial environments.

  16. Immobilized metal ion affinity chromatography ZipTip pipette tip with polydopamine modification and Ti⁴⁺ immobilization for selective enrichment and isolation of phosphopeptides.

    PubMed

    Shi, Chenyi; Deng, Chunhui

    2015-10-01

    As an effective tool in protein analysis, mass spectroscopy (MS) has been widely used in identifying protein phosphorylation and phosphorylation sites. Because of the low abundance of phosphopeptides in protein digestion, isolation and enrichment of phosphopeptides prior to MS analysis is important for efficient phosphopeptides identification. In this work, we initially immobilized titanium ions on polydopamine (PDA)-modified ZipTip pipette tips (denoted as IMAC ZipTip pipette tip) for simple and quick enrichment of phosphopeptides. The preparation process of the novel ZipTip pipette tips is fast and economic since it only contains two simple steps both with mild conditions. The ability of modified ZipTip pipette tips for identifying phosphopeptides in complex biological samples was investigated. The unique ZipTip pipette tip not only exhibited superior ability in selectively capturing phosphopeptides from large amount of non-phosphopeptides, but also remarkably shortened the MS preparation and analysis time, making it an easy-to-use and efficient tool in phosphoproteome research. PMID:26078185

  17. A resolution of the paradox of enrichment.

    PubMed

    Mougi, Akihiko; Nishimura, Kinya

    2007-09-01

    Theoretical studies have shown a paradoxical destabilizing response of predator-prey ecosystems to enrichment, but there is the gap between the intuitive view of nature and this theoretical prediction. We studied a minimal predator-prey system (a two predator-two prey system) in which the paradox of enrichment pattern can vanish; the destabilization with enrichment is reversed, leading to stabilization (a decrease in the amplitude of oscillation of population densities). For resolution of the paradox, two conditions must be met: (1) the same prey species must be preferred as a dietary item by both predator species, creating the potential for high exploitative competition between the predator species, and (2), while both predators are assumed to select their diet in accordance with optimal diet utilization theory, one predator must be a specialist and the other a generalist. In this system, the presence of a less profitable prey species can cause the increase in population oscillation amplitudes associated with increasing enrichment to be suppressed via the optimal diet utilization of the generalist predator. The resulting stabilization is explained by the mitigating effect of the less profitable prey showing better population growth with increasing enrichment on the destabilization underlying the specialist predator and prey relation, thus resolving the paradox of enrichment. PMID:17543997

  18. Improvement of aromatic thiol release through the selection of yeasts with increased β-lyase activity.

    PubMed

    Belda, Ignacio; Ruiz, Javier; Navascués, Eva; Marquina, Domingo; Santos, Antonio

    2016-05-16

    The development of a selective medium for the rapid differentiation of yeast species with increased aromatic thiol release activity has been achieved. The selective medium was based on the addition of S-methyl-l-cysteine (SMC) as β-lyase substrate. In this study, a panel of 245 strains of Saccharomyces cerevisiae strains was tested for their ability to grow on YCB-SMC medium. Yeast strains with an increased β-lyase activity grew rapidly because of their ability to release ammonium from SMC in comparison to others, and allowed for the easy isolation and differentiation of yeasts with promising properties in oenology, or another field, for aromatic thiol release. The selective medium was also helpful for the discrimination between those S. cerevisiae strains, which present a common 38-bp deletion in the IRC7 sequence (present in around 88% of the wild strains tested and are likely to be less functional for 4-mercapto-4-methylpentan-2-one (4MMP) production), and those S. cerevisiae strains homozygous for the full-length IRC7 allele. The medium was also helpful for the selection of non-Saccharomyces yeasts with increased β-lyase activity. Based on the same medium, a highly sensitive, reproducible and non-expensive GC-MS method for the evaluation of the potential volatile thiol release by different yeast isolates was developed. PMID:26971012

  19. White bread enriched with polyphenol extracts shows no effect on glycemic response or satiety, yet may increase postprandial insulin economy in healthy participants.

    PubMed

    Coe, Shelly; Ryan, Lisa

    2016-02-01

    Extracts from different plant sources have been shown to modify starch digestion from carbohydrate-rich foods and lower resulting glycemia. It was hypothesized that extracts rich in polyphenols, added to white bread, would improve the glycemic response and insulin response and increase satiety in healthy participants. An in vitro dose-response analysis was performed to determine the optimal dose of a variety of extracts (baobab fruit extract, green tea extract, grape seed extract, and resveratrol) for reducing rapidly digestible starch in white bread. The 2 extracts with the greatest sugar reducing potential were then used for the human study in which 13 volunteers (9 female and 4 male) were recruited for a crossover trial of 3 different meals. On separate days, participants consumed a control white bread, white bread with green tea extract (0.4%), and white bread with baobab fruit extract (1.88%). Glycemic response, insulin response, and satiety were measured 3 hours postprandially. Although enriched breads did not reduce glycemic response or hunger, white bread with added baobab fruit extract significantly (P < .05) reduced the total (0-180 minutes) and segmental insulin area under the curve at 0 to 90, 0 to 120, and 0 to 150 minutes, and therefore reduced the amount of insulin needed for a given blood glucose response. This preliminary research suggests that there is potential for baobab fruit extract added into white bread to improve insulin economy in healthy adults. PMID:26612114

  20. Tailor-Made Boronic Acid Functionalized Magnetic Nanoparticles with a Tunable Polymer Shell-Assisted for the Selective Enrichment of Glycoproteins/Glycopeptides.

    PubMed

    Zhang, Xihao; Wang, Jiewen; He, Xiwen; Chen, Langxing; Zhang, Yukui

    2015-11-11

    Biomedical sciences, and in particular biomarker research, demand efficient glycoproteins enrichment platforms. In this work, we present a facile and time-saving method to synthesize phenylboronic acid and copolymer multifunctionalized magnetic nanoparticles (NPs) using a distillation-precipitation polymerization (DPP) technique. The polymer shell is obtained through copolymerization of two monomers-affinity ligand 3-acrylaminophenylboronic acid (AAPBA) and a hydrophilic functional monomer. The resulting hydrophilic Fe3O4@P(AAPBA-co-monomer) NPs exhibit an enhanced binding capacity toward glycoproteins by an additional functional monomer complementary to the surface presentation of the target protein. The effects of monomer ratio of AAPBA to hydrophilic comonomers on the binding of glycoproteins are systematically investigated. The morphology, structure, and composition of all the synthesized microspheres are characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM). The hydrophilic Fe3O4@P(AAPBA-co-monomer) microspheres show an excellent performance in the separation of glycoproteins with high binding capacity; And strong magnetic response allows them to be easily separated from solution in the presence of an external magnetic field. Moreover, both synthetic Fe3O4@P(AAPBA) and copolymeric NPs show good adsorption to glycoproteins in physiological conditions (pH 7.4). The Fe3O4@P(AAPBA-co-monomer) NPs are successfully utilized to selectively capture and identify the low-abundance glycopeptides from the tryptic digest of horseradish peroxidase (HRP). In addition, the selective isolation and enrichment of glycoproteins from the egg white samples at physiological condition is obtained by Fe3O4@P(AAPBA-co-monomer) NPs as adsorbents. PMID:26479332

  1. Evolution of Protein Quaternary Structure in Response to Selective Pressure for Increased Thermostability.

    PubMed

    Fraser, Nicholas J; Liu, Jian-Wei; Mabbitt, Peter D; Correy, Galen J; Coppin, Chris W; Lethier, Mathilde; Perugini, Matthew A; Murphy, James M; Oakeshott, John G; Weik, Martin; Jackson, Colin J

    2016-06-01

    Oligomerization has been suggested to be an important mechanism for increasing or maintaining the thermostability of proteins. Although it is evident that protein-protein contacts can result in substantial stabilization in many extant proteins, evidence for evolutionary selection for oligomerization is largely indirect and little is understood of the early steps in the evolution of oligomers. A laboratory-directed evolution experiment that selected for increased thermostability in the αE7 carboxylesterase from the Australian sheep blowfly, Lucilia cuprina, resulted in a thermostable variant, LcαE7-4a, that displayed increased levels of dimeric and tetrameric quaternary structure. A trade-off between activity and thermostability was made during the evolution of thermostability, with the higher-order oligomeric species displaying the greatest thermostability and lowest catalytic activity. Analysis of monomeric and dimeric LcαE7-4a crystal structures revealed that only one of the oligomerization-inducing mutations was located at a potential protein-protein interface. This work demonstrates that by imposing a selective pressure demanding greater thermostability, mutations can lead to increased oligomerization and stabilization, providing support for the hypothesis that oligomerization is a viable evolutionary strategy for protein stabilization. PMID:27016206

  2. Immunoaffinity enrichment and liquid chromatography-selected reaction monitoring mass spectrometry for quantitation of carbonic anhydrase 12 in cultured renal carcinoma cells

    PubMed Central

    Rafalko, Agnes; Iliopoulos, Othon; Fusaro, Vincent A.; Hancock, William; Hincapie, Marina

    2010-01-01

    Liquid chromatography-selected reaction monitoring (LC-SRM) is a highly specific and sensitive mass spectrometry (MS) technique that is widely being applied to selectively qualify and validate candidate markers within complex biological samples. However, in order for LC-SRM methods to take on these attributes, target-specific optimization of sample processing is required, in order to reduce analyte complexity, prior to LC-SRM. In this study, we have developed a targeted platform consisting of protein immunoaffinity enrichment on magnetic beads and LC-SRM for measuring carbonic anhydrase 12 (CA12) protein in a renal cell carcinoma (RCC) cell line (PRC3), a candidate biomarker for RCC whose expression at the protein level has not been previously reported. Sample processing and LC-SRM assay were optimized for signature peptides selected as surrogate markers of CA12 protein. Using LC-SRM coupled with stable isotope dilution, we achieved limits of quantitation in the low fmol range sufficient for measuring clinically relevant biomarkers with good intra- and inter-assay accuracy and precision (≤17%). Our results show that using a quantitative immunoaffinity capture approach provides specific, accurate, and robust assays amenable to high-throughput verification of potential biomarkers. PMID:20936840

  3. Immunoaffinity enrichment and liquid chromatography-selected reaction monitoring mass spectrometry for quantitation of carbonic anhydrase 12 in cultured renal carcinoma cells.

    PubMed

    Rafalko, Agnes; Iliopoulos, Othon; Fusaro, Vincent A; Hancock, William; Hincapie, Marina

    2010-11-01

    Liquid chromatography-selected reaction monitoring (LC-SRM) is a highly specific and sensitive mass spectrometry (MS) technique that is widely being applied to selectively qualify and validate candidate markers within complex biological samples. However, in order for LC-SRM methods to take on these attributes, target-specific optimization of sample processing is required, in order to reduce analyte complexity, prior to LC-SRM. In this study, we have developed a targeted platform consisting of protein immunoaffinity enrichment on magnetic beads and LC-SRM for measuring carbonic anhydrase 12 (CA12) protein in a renal cell carcinoma (RCC) cell line (PRC3), a candidate biomarker for RCC whose expression at the protein level has not been previously reported. Sample processing and LC-SRM assay were optimized for signature peptides selected as surrogate markers of CA12 protein. Using LC-SRM coupled with stable isotope dilution, we achieved limits of quantitation in the low fmol range sufficient for measuring clinically relevant biomarkers with good intra- and interassay accuracy and precision (≤17%). Our results show that using a quantitative immunoaffinity capture approach provides specific, accurate, and robust assays amenable to high-throughput verification of potential biomarkers. PMID:20936840

  4. High fat diet enriched with saturated, but not monounsaturated fatty acids adversely affects femur, and both diets increase calcium absorption in older female mice.

    PubMed

    Wang, Yang; Dellatore, Peter; Douard, Veronique; Qin, Ling; Watford, Malcolm; Ferraris, Ronaldo P; Lin, Tiao; Shapses, Sue A

    2016-07-01

    Diet induced obesity has been shown to reduce bone mineral density (BMD) and Ca absorption. However, previous experiments have not examined the effect of high fat diet (HFD) in the absence of obesity or addressed the type of dietary fatty acids. The primary objective of this study was to determine the effects of different types of high fat feeding, without obesity, on fractional calcium absorption (FCA) and bone health. It was hypothesized that dietary fat would increase FCA and reduce BMD. Mature 8-month-old female C57BL/6J mice were fed one of three diets: a HFD (45% fat) enriched either with monounsaturated fatty acids (MUFAs) or with saturated fatty acids (SFAs), and a normal fat diet (NFD; 10% fat). Food consumption was controlled to achieve a similar body weight gain in all groups. After 8wk, total body bone mineral content and BMD as well as femur total and cortical volumetric BMD were lower in SFA compared with NFD groups (P<.05). In contrast, femoral trabecular bone was not affected by the SFAs, whereas MUFAs increased trabecular volume fraction and thickness. The rise over time in FCA was greater in mice fed HFD than NFD and final FCA was higher with HFD (P<.05). Intestinal calbindin-D9k gene and hepatic cytochrome P450 2r1 protein levels were higher with the MUFA than the NFD diet (P<.05). In conclusion, HFDs elevated FCA overtime; however, an adverse effect of HFD on bone was only observed in the SFA group, while MUFAs show neutral or beneficial effects. PMID:27262536

  5. Increasing the size of portion options affects intake but not portion selection at a meal.

    PubMed

    Zuraikat, Faris M; Roe, Liane S; Privitera, Gregory J; Rolls, Barbara J

    2016-03-01

    In an environment with large portion sizes, allowing consumers more control over their portion selection could moderate the effects on energy intake. We tested whether having subjects choose a portion from several options influenced the amount selected or consumed when all portion sizes were systematically increased. In a crossover design, 24 women and 26 men ate lunch in the lab once a week for 3 weeks. At each meal, subjects chose a portion of macaroni and cheese from a set of 3 portion options and consumed it ad libitum. Across 3 conditions, portion sizes in the set were increased; the order of the conditions was counterbalanced across subjects. For women the portion sets by weight (g) were 300/375/450, 375/450/525, and 450/525/600; for men the portions were 33% larger. The results showed that increasing the size of available portions did not significantly affect the relative size selected; across all portion sets, subjects chose the smallest available portion at 59% of meals, the medium at 27%, and the largest at 15%. The size of portions offered did, however, influence meal intake (P < 0.0001). Mean intake (±SEM) was 16% greater when the largest set was offered (661 ± 34 kcal) than when the medium and smallest sets were offered (both 568 ± 18 kcal). These results suggest that portions are selected in relation to the other available options, and confirm the robust effect of portion size on intake. Although presenting a choice of portions can allow selection of smaller amounts, the sizes offered are a critical determinant of energy intake. Thus, the availability of choices could help to moderate intake if the portions offered are within an appropriate range for energy needs. PMID:26721718

  6. Strong Artificial Selection in Domestic Mammals Did Not Result in an Increased Recombination Rate

    PubMed Central

    Muñoz-Fuentes, Violeta; Marcet-Ortega, Marina; Alkorta-Aranburu, Gorka; Linde Forsberg, Catharina; Morrell, Jane M.; Manzano-Piedras, Esperanza; Söderberg, Arne; Daniel, Katrin; Villalba, Adrian; Toth, Attila; Di Rienzo, Anna; Roig, Ignasi; Vilà, Carles

    2015-01-01

    Recombination rates vary in intensity and location at the species, individual, sex and chromosome levels. Despite the fundamental biological importance of this process, the selective forces that operate to shape recombination rate and patterns are unclear. Domestication offers a unique opportunity to study the interplay between recombination and selection. In domesticates, intense selection for particular traits is imposed on small populations over many generations, resulting in organisms that differ, sometimes dramatically, in morphology and physiology from their wild ancestor. Although earlier studies suggested increased recombination rate in domesticates, a formal comparison of recombination rates between domestic mammals and their wild congeners was missing. In order to determine broad-scale recombination rate, we used immunolabeling detection of MLH1 foci as crossover markers in spermatocytes in three pairs of closely related wild and domestic species (dog and wolf, goat and ibex, and sheep and mouflon). In the three pairs, and contrary to previous suggestions, our data show that contemporary recombination rate is higher in the wild species. Subsequently, we inferred recombination breakpoints in sequence data for 16 genomic regions in dogs and wolves, each containing a locus associated with a dog phenotype potentially under selection during domestication. No difference in the number and distribution of recombination breakpoints was found between dogs and wolves. We conclude that our data indicate that strong directional selection did not result in changes in recombination in domestic mammals, and that both upper and lower bounds for crossover rates may be tightly regulated. PMID:25414125

  7. Using Negative Reinforcement to Increase Self-Feeding in a Child with Food Selectivity

    ERIC Educational Resources Information Center

    Vaz, Petula C. M.; Volkert, Valerie M.; Piazza, Cathleen C.

    2011-01-01

    We examined the effects of a negative reinforcement-based treatment on the self-feeding of 1 child with food selectivity by type and texture. Self-feeding increased when the child could choose to either self-feed 1 bite of a target food or be fed 1 bite of the target food and 5 bites of another food. Possible mechanisms that underlie the…

  8. Piperlongumine selectively kills cancer cells and increases cisplatin antitumor activity in head and neck cancer

    PubMed Central

    Roh, Jong-Lyel; Kim, Eun Hye; Park, Jin Young; Kim, Ji Won; Kwon, Minsu; Lee, Byung-Heon

    2014-01-01

    Adaptation to cellular stress is not a vital function of normal cells but is required of cancer cells, and as such might be a sensible target in cancer therapy. Piperlongumine is a naturally occurring small molecule selectively toxic to cancer cells. This study assesses the cytotoxicity of piperlongumine and its combination with cisplatin in head-and-neck cancer (HNC) cells in vitro and in vivo. The effect of piperlongumine, alone and in combination with cisplatin, was assessed in human HNC cells and normal cells by measuring growth, death, cell cycle progression, reactive oxygen species (ROS) production, and protein expression, and in tumor xenograft mouse models. Piperlongumine killed HNC cells regardless of p53 mutational status but spared normal cells. It increased ROS accumulation in HNC cells, an effect that can be blocked by the antioxidant N-acetyl-L-cysteine. Piperlongumine induced selective cell death in HNC cells by targeting the stress response to ROS, leading to the induction of death pathways involving JNK and PARP. Piperlongumine increased cisplatin-induced cytotoxicity in HNC cells in a synergistic manner in vitro and in vivo. Piperlongumine might be a promising small molecule with which to selectively kill HNC cells and increase cisplatin antitumor activity by targeting the oxidative stress response. PMID:25193861

  9. Piperlongumine selectively kills cancer cells and increases cisplatin antitumor activity in head and neck cancer.

    PubMed

    Roh, Jong-Lyel; Kim, Eun Hye; Park, Jin Young; Kim, Ji Won; Kwon, Minsu; Lee, Byung-Heon

    2014-10-15

    Adaptation to cellular stress is not a vital function of normal cells but is required of cancer cells, and as such might be a sensible target in cancer therapy. Piperlongumine is a naturally occurring small molecule selectively toxic to cancer cells. This study assesses the cytotoxicity of piperlongumine and its combination with cisplatin in head-and-neck cancer (HNC) cells in vitro and in vivo. The effect of piperlongumine, alone and in combination with cisplatin, was assessed in human HNC cells and normal cells by measuring growth, death, cell cycle progression, reactive oxygen species (ROS) production, and protein expression, and in tumor xenograft mouse models. Piperlongumine killed HNC cells regardless of p53 mutational status but spared normal cells. It increased ROS accumulation in HNC cells, an effect that can be blocked by the antioxidant N-acetyl-L-cysteine. Piperlongumine induced selective cell death in HNC cells by targeting the stress response to ROS, leading to the induction of death pathways involving JNK and PARP. Piperlongumine increased cisplatin-induced cytotoxicity in HNC cells in a synergistic manner in vitro and in vivo. Piperlongumine might be a promising small molecule with which to selectively kill HNC cells and increase cisplatin antitumor activity by targeting the oxidative stress response. PMID:25193861

  10. Evolution of increased adult longevity in Drosophila melanogaster populations selected for adaptation to larval crowding.

    PubMed

    Shenoi, V N; Ali, S Z; Prasad, N G

    2016-02-01

    In holometabolous animals such as Drosophila melanogaster, larval crowding can affect a wide range of larval and adult traits. Adults emerging from high larval density cultures have smaller body size and increased mean life span compared to flies emerging from low larval density cultures. Therefore, adaptation to larval crowding could potentially affect adult longevity as a correlated response. We addressed this issue by studying a set of large, outbred populations of D. melanogaster, experimentally evolved for adaptation to larval crowding for 83 generations. We assayed longevity of adult flies from both selected (MCUs) and control populations (MBs) after growing them at different larval densities. We found that MCUs have evolved increased mean longevity compared to MBs at all larval densities. The interaction between selection regime and larval density was not significant, indicating that the density dependence of mean longevity had not evolved in the MCU populations. The increase in longevity in MCUs can be partially attributed to their lower rates of ageing. It is also noteworthy that reaction norm of dry body weight, a trait probably under direct selection in our populations, has indeed evolved in MCU populations. To the best of our knowledge, this is the first report of the evolution of adult longevity as a correlated response of adaptation to larval crowding. PMID:26575793