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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 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

  4. Mung Bean Nuclease Treatment Increases Capture Specificity of Microdroplet-PCR Based Targeted DNA Enrichment

    PubMed Central

    Yu, Zhenming; Cao, Kajia; Tischler, Tanya; Stolle, Catherine A.; Santani, Avni B.

    2014-01-01

    Targeted DNA enrichment coupled with next generation sequencing has been increasingly used for interrogation of select sub-genomic regions at high depth of coverage in a cost effective manner. Specificity measured by on-target efficiency is a key performance metric for target enrichment. Non-specific capture leads to off-target reads, resulting in waste of sequencing throughput on irrelevant regions. Microdroplet-PCR allows simultaneous amplification of up to thousands of regions in the genome and is among the most commonly used strategies for target enrichment. Here we show that carryover of single-stranded template genomic DNA from microdroplet-PCR constitutes a major contributing factor for off-target reads in the resultant libraries. Moreover, treatment of microdroplet-PCR enrichment products with a nuclease specific to single-stranded DNA alleviates off-target load and improves enrichment specificity. We propose that nuclease treatment of enrichment products should be incorporated in the workflow of targeted sequencing using microdroplet-PCR for target capture. These findings may have a broad impact on other PCR based applications for which removal of template DNA is beneficial. PMID:25058678

  5. 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.

  6. Environmental enrichment improves response strength, threshold, selectivity, and latency of auditory cortex neurons.

    PubMed

    Engineer, Navzer D; Percaccio, Cherie R; Pandya, Pritesh K; Moucha, Raluca; Rathbun, Daniel L; Kilgard, Michael P

    2004-07-01

    Over the last 50 yr, environmental enrichment has been shown to generate more than a dozen changes in brain anatomy. The consequences of these physical changes on information processing have not been well studied. In this study, rats were housed in enriched or standard conditions either prior to or after reaching sexual maturity. Evoked potentials from awake rats and extracellular recordings from anesthetized rats were used to document responses of auditory cortex neurons. This report details several significant, new findings about the influence of housing conditions on the responses of rat auditory cortex neurons. First, enrichment dramatically increases the strength of auditory cortex responses. Tone-evoked potentials of enriched rats, for example, were more than twice the amplitude of rats raised in standard laboratory conditions. Second, cortical responses of both young and adult animals benefit from exposure to an enriched environment and are degraded by exposure to an impoverished environment. Third, housing condition resulted in rapid remodeling of cortical responses in <2 wk. Fourth, recordings made under anesthesia indicate that enrichment increases the number of neurons activated by any sound. This finding shows that the evoked potential plasticity documented in awake rats was not due to differences in behavioral state. Finally, enrichment made primary auditory cortex (A1) neurons more sensitive to quiet sounds, more selective for tone frequency, and altered their response latencies. These experiments provide the first evidence of physiologic changes in auditory cortex processing resulting from generalized environmental enrichment.

  7. 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

  8. 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

  9. Environmental Enrichment Therapy for Autism: Outcomes with Increased Access

    PubMed Central

    Aronoff, Eyal

    2016-01-01

    We have previously shown in two randomized clinical trials that environmental enrichment is capable of ameliorating symptoms of autism spectrum disorder (ASD), and in the present study, we determined whether this therapy could be effective under real-world circumstances. 1,002 children were given daily Sensory Enrichment Therapy, by their parents, using personalized therapy instructions given over the Internet. Parents were asked to assess the symptoms of their child every 2 weeks for up to 7 months. An intention-to-treat analysis showed significant overall gains for a wide range of symptoms in these children, including learning, memory, anxiety, attention span, motor skills, eating, sleeping, sensory processing, self-awareness, communication, social skills, and mood/autism behaviors. The children of compliant caregivers were more likely to experience a significant improvement in their symptoms. The treatment was effective across a wide age range and there was equal progress reported for males and females, for USA and international subjects, for those who paid and those who did not pay for the therapy, and for individuals at all levels of initial symptom severity. Environmental enrichment, delivered via an online system, therefore appears to be an effective, low-cost means of treating the symptoms of ASD. PMID:27721995

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

    PubMed

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

    2013-09-01

    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; 0.5mg/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.

  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. 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...

  13. 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.

  14. 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.

  15. 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.

  16. A high boronate avidity monolithic capillary for the selective enrichment of trace glycoproteins.

    PubMed

    Li, Daojin; Li, Yang; Li, Xinglin; Bie, Zijun; Pan, Xianghua; Zhang, Qian; Liu, Zhen

    2015-03-01

    Boronate affinity materials, as effective sample enrichment sorbents for glycoproteomic analysis, have attracted increasing attention in recent years. However, most of boronate affinity materials suffer from an apparent limitation, limited binding strength. As a result, extraction of glycoproteins of trace concentration is rather difficult or impossible. In this study, we present a high boronate avidity monolithic capillary. Branched polyethyleneimine (PEI) was used as a scaffold to amplify the number of boronic acid moieties. While 2,4-difluoro-3-formyl-phenylboronic acid (DFFPBA), which exhibited ultrahigh affinity toward cis-diol-containing compounds, was employed as an affinity ligand. Due to the PEI-assisted synergistic multivalent binding, the monolithic column exhibited high boronate avidity toward glycoproteins, with binding constants of 10(-6)-10(-7)M. Such binding strength was the highest among already reported boronic acid-functionalized materials that can be used for glycoproteomic analysis. Besides, the boronate avidity monolithic column exhibited one additional beneficial feature, lowered binding pH (≥6.5). These features greatly favored the selective enrichment of trace glycoproteins from real samples. The feasibility for practical applications was demonstrated with the selective enrichment of trace glycoproteins in human saliva. As compared with other boronate avidity/affinity materials, the boronate avidity monolithic capillary exhibited the best performance.

  17. Cage enrichment with paper tissue, but not plastic tunnels, increases variability in mouse model of asthma.

    PubMed

    Pasalic, I; Bosnjak, B; Tkalcevic, V Ivetic; Jaran, D Seveljevic; Javorscak, Z; Markovic, D; Hrvacic, B

    2011-04-01

    Environmental enrichment, besides having a great impact on animal welfare, can also be a potential variable in experimental research. Thus, we investigated whether enrichment of cages with paper tissues or plastic tunnels affects scientific outcome in the well-described mouse model of allergic asthma. BALB/cJ mice were introduced to paper tissues as nesting material, transparent plastic tunnels serving as shelters or kept in non-enriched cages. Afterwards, mice were sensitized to chicken egg ovalbumin (OVA) precipitated in aluminium sulphate and then intranasally challenged with OVA to induce allergic lung inflammation. Mice housed in cages enriched with paper tissues, but not with plastic tunnels, had increased total cell number, eosinophil number and IL-13 concentration in bronchoalveolar lavage fluid in comparison with the non-enriched control group. These results indicate that the effect of environmental enrichment on mice asthma models depends on the type of enrichment used. Therefore, it is important to consider the potential effects of any environmental enrichment on animal welfare and more importantly, on research results in order to standardize and obtain more accurate data from rodent studies.

  18. Environmental enrichment increases paired-pulse depression in rat auditory cortex.

    PubMed

    Percaccio, Cherie R; Engineer, Navzer D; Pruette, Autumn L; Pandya, Pritesh K; Moucha, Raluca; Rathbun, Daniel L; Kilgard, Michael P

    2005-11-01

    Temporal features are important for the identification of natural sounds. Earlier studies have shown that cortical processing of temporal information can be altered by long-term experience with modulated sounds. In a previous study, we observed that environmental enrichment dramatically increased the response of cortical neurons to single tone and noise burst stimuli in both awake and anesthetized rats. Here, we evaluate how enrichment influences temporal information processing in the auditory cortex. We recorded responses to repeated tones and noise bursts in awake rats using epidural evoked potentials and in anesthetized rats using microelectrodes. Enrichment increased the response of cortical neurons to stimuli presented at slow rates and decreased the response to stimuli presented at fast rates relative to controls. Our observation that enrichment substantially increased response strength and forward masking is consistent with earlier reports that long-term potentiation of cortical synapses is associated with increased paired-pulse depression. Enrichment also increased response synchronization at slow rates and decreased synchronization at fast rates. Paired-pulse depression increased within days of environmental enrichment and was restored to normal levels after return to standard housing conditions. These results are relevant to several clinical disorders characterized by abnormal gating of sensory information, including autism, schizophrenia, and dyslexia.

  19. 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

  20. 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.

  1. Magnetic cellulose-TiO2 nanocomposite microspheres for highly selective enrichment of phosphopeptides.

    PubMed

    Duan, Jiangjiang; He, Xiaomei; Zhang, Lina

    2015-01-01

    Novel magnetic cellulose-TiO2 nanocomposite microspheres with high surface areas and magnetic susceptibility were fabricated, which exhibited remarkably selective enrichment of trace phosphopeptides from peptide mixtures. PMID:25407892

  2. A mathematical analysis of the selective enrichment of NECEEM-based non-SELEX.

    PubMed

    Yu, Xinliang; Yu, Yixiong

    2014-08-01

    Non-Systematic Evolution of Ligands by EXponential enrichment (SELEX)selection of aptamers, a novel technology for aptamer selection from libraries of random DNA (or RNA) sequences, involves repetitive steps of partitioning without polymerase chain reaction (PCR) amplification between them. This selection is based on non-equilibrium capillary electrophoresis of equilibrium mixtures (NECEEM) and has exceptionally high efficiency. In this paper, a mathematical analysis was carried out to predict the levels of enrichment of non-SELEX selection under different conditions such as different protein concentrations and different efficiencies of partitioning. Investigated results suggest that the magnitude of the bulk affinity (k d) being 10(4) or 10(5) μM for the initial pool has no obvious effect on selective enrichment and that the first, second, and third rounds of non-SELEX selection have different optimum protein concentration values [T f] that give maximum enrichment levels when [T f] ranges from 0.0005 to 0.5 μM. The significance of analyzing selective enrichment of NECEEM-based non-SELEX with the efficiency of partitioning target-bound ligands from free ligands has been demonstrated.

  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. Microfluidic chip system for the selection and enrichment of cell binding aptamers

    PubMed Central

    Stoll, Heidi; Kiessling, Heiko; Stelzle, Martin; Wendel, Hans Peter; Schütte, Julia; Hagmeyer, Britta; Avci-Adali, Meltem

    2015-01-01

    Aptamers are promising cell targeting ligands for several applications such as for the diagnosis, therapy, and drug delivery. Especially, in the field of regenerative medicine, stem cell specific aptamers have an enormous potential. Using the combinatorial chemistry process SELEX (Systematic Evolution of Ligands by Exponential enrichment), aptamers are selected from a huge oligonucleotide library consisting of approximately 1015 different oligonucleotides. Here, we developed a microfluidic chip system that can be used for the selection of cell specific aptamers. The major drawbacks of common cell-SELEX methods are the inefficient elimination of the unspecifically bound oligonucleotides from the cell surface and the unspecific binding/uptake of oligonucleotides by dead cells. To overcome these obstacles, a microfluidic device, which enables the simultaneous performance of dielectrophoresis and electrophoresis in the same device, was designed. Using this system, viable cells can be selectively assembled by dielectrophoresis between the electrodes and then incubated with the oligonucleotides. To reduce the rate of unspecifically bound sequences, electrophoretic fields can be applied in order to draw loosely bound oligonucleotides away from the cells. Furthermore, by increasing the flow rate in the chip during the iterative rounds of SELEX, the selection pressure can be improved and aptamers with higher affinities and specificities can be obtained. This new microfluidic device has a tremendous capability to improve the cell-SELEX procedure and to select highly specific aptamers. PMID:26180568

  6. 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.

  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. 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.

  9. Selective enrichment of phosphopeptides by titania nanoparticles coated magnetic carbon nanotubes.

    PubMed

    Yan, Yinghua; Zheng, Zhifang; Deng, Chunhui; Zhang, Xiangmin; Yang, Pengyuan

    2014-01-01

    Selective enrichment of phosphoproteins or phosphopeptides from complex mixtures is essential for mass spectrometry (MS)-based phosphoproteomics. In this work, for the first time, titania nanoparticles coated magnetic carbon nanotubes (denoted as MagCNTs@TiO₂ composites) were synthesized through a facile but effective solvothermal reaction for selective enrichment of phosphopeptides. The MagCNTs@TiO₂ material demonstrated low limit of detection (20 fmol), along with an exceptional great specificity to capture phosphopeptides from a tryptic digest of the mixture of a nonphosphorylated protein BSA and a phosphorylated protein β-casein with molar ratios of BSA/β-casein up to 200:1. In addition, the high magnetic susceptibility allowed convenient separation of the target peptides by magnetic separation. Experimental results demonstrated that the MagCNTs@TiO₂ composites showed excellent potential for the selective enrichment of phosphopeptides for MS analysis. PMID:24274265

  10. 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.

  11. 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

  12. 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.

  13. Development of Hf(4+)-immobilized polydopamine-coated magnetic graphene for highly selective enrichment of phosphopeptides.

    PubMed

    Lin, Haizhu; Deng, Chunhui

    2016-01-01

    In this work, we first designed and synthesized an IMAC material with Hf(4+) immobilized on polydopamine-coated magnetic graphene and applied it to phosphopeptides enrichment successfully. The newly prepared material gathered the advantages of large specific surface area of graphene, good hydrophilicity and biocompatibility of polydopamine and superparamagnetism of Fe3O4. We investigated the performance of Hf(4+)-immobilized polydopamine-coated magnetic graphene (denoted as magG@PDA-Hf(4+)) in phosphopeptides enrichment and the results showed high selectivity and sensitivity of the new material. Finally, we successfully applied magG@PDA-Hf(4+) to phosphopeptides enrichment from non-fat milk digests and human serum, further demonstrating excellent performance of this new material in phosphopeptides enrichment.

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

    PubMed

    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

  16. Dietary fatty acid enrichment increases egg size and quality of yellow seahorse Hippocampus kuda.

    PubMed

    Saavedra, M; Masdeu, M; Hale, P; Sibbons, C M; Holt, W V

    2014-02-01

    Seahorses populations in the wild have been declining and to restore them a better knowledge of seahorse reproduction is required. This study examines the effect of dietary quality on seahorse fecundity and egg quality. Two different diets were tested with Hippocampus kuda females: frozen mysis (control) and frozen mysis enriched with a liposome spray containing essential fatty acids. Diets were given to females (two groups of five) over a seven week period. After this period, males (fed the control diet) and females were paired and the eggs dropped by the females were collected. Fatty acid profile were analysed and eggs were counted and measured. Results showed that females fed on enriched mysis had larger eggs and that these had a higher content of total polyunsaturated fatty acids. The size of the egg was especially affected in the first spawn, where egg size for females fed the enriched diet was significantly higher than the egg size from control females. This effect was reduced in the following spawning where no significant differences were found. Egg size is an important quality descriptor as seahorse juveniles originating from smaller eggs and/or eggs of poor quality will have less chances of overcoming adverse conditions in the wild and consequently have lower survival and growth rates. This study shows that enriching frozen mysis with polyunsaturated fatty acids increases egg size and egg quality of H. kuda.

  17. 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%.

  18. 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...

  19. 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...

  20. Glycoprotein enrichment method using a selective magnetic nano-probe platform (MNP) functionalized with lectins.

    PubMed

    Cova, Marta; Oliveira-Silva, Rui; Ferreira, José Alexandre; Ferreira, Rita; Amado, Francisco; Daniel-da-Silva, Ana Luísa; Vitorino, Rui

    2015-01-01

    Protein post-translational modifications (PTMs) have increasingly become a research field of incredible importance to fully understand the regulation of biological processes in health and disease. Among PTMs, glycosylation is one of the most studied for which contributed the development and improvement of enrichment techniques. Nowadays, glycoprotein enrichment methods are based on lectin affinity, covalent interactions, and hydrophilic interaction liquid chromatography (HILIC). Nonetheless, the nanotechnology era has fetched new methods to enrich glycoproteins from complex samples as human biological fluids. For instance, magnetic nanoparticles (MNPs) are being used as an interesting enrichment approach allowing a better characterization of glycoproteins and glycopeptides.In this chapter, we describe an enrichment method based on MNPs functionalized with lectins (Concavalin A, wheat germ agglutinin, and Maackia amurensis lectin) to enrich specific sets of glycoproteins from biological fluids. Moreover, it is proposed a bioinformatic strategy to deal with data retrieved from mass spectrometry analysis of enriched samples aiming the identification of relevant biological processes modulated by a given stimuli and, ultimately, of new biomarkers for disease screening/management.

  1. Characterization of enriched aerotolerant cellulose-degrading communities for biofuels production using differing selection pressures and inoculum sources.

    PubMed

    Wushke, Scott; Levin, David B; Cicek, Nazim; Sparling, Richard

    2013-10-01

    Ethanol production from direct cellulose fermentation has mainly been described as a strictly anaerobic process. The use of air-tolerant organisms or consortia for this process would reduce the need for prereduction of the medium and also permit continuous feed of aerobic feedstock. To this end, moderately thermophilic (60 °C) consortia of fermentative, cellulolytic bacteria were enriched from 3 distinct environments (manure, marsh, and rotten wood) from a farm in southeast Saskatchewan, Canada. Community phenotypic and metabolic profiles were characterized. Selection methods included direct plating under an aerobic atmosphere and repeated passaging; the methods were designed to select for robust, stable aerotolerant cellulose-degrading communities. Several of the isolated communities exhibited an increase in total cellulose degradation and total ethanol yield when compared with a monoculture of Clostridium thermocellum DSMZ 1237. Owing to stringent selection conditions, low diversity enrichments were found, and many appeared to be binary cultures via density gradient gel electrophoresis analysis. On the basis of 16S rRNA gene sequencing, aerobic conditions selected for a mix of organisms highly related to C. thermocellum and Geobacillus species, while anaerobic conditions led to the development of consortia containing strains related to C. thermocellum with strains from either the genus Geobacillus or the genus Thermoanaerobacter. The presence of a Geobacillus-like species appeared to be a prerequisite for aerotolerance of the cellulolytic enrichments, a highly desired phenotype in lignocellulosic consolidated bioprocessing.

  2. Effects of selected behavioral enrichment devices on behavior of Western Lowland Gorillas (Gorilla gorilla gorilla).

    PubMed

    Rooney, M B; Sleeman, J

    1998-01-01

    Environmental complexity plays an integral role in the activity and psychological well-being of primates. The experiment described in this article evaluates the effects of nonintrusive, inexpensive, and easily managed behavioral enrichment devices on the behavior of a group of captive Western lowland gorillas. Devices used included cardboard boxes containing food items, paper bags containing food items, burlap rags, and willow and maple browse. The enrichment devices increased foraging, social play, and solitary play behaviors. Sedentary behaviors decreased. Rags, bags, browse, and boxes did not statistically decrease the incidence of regurgitation/reingestation or coprophagy. Depending on the type of enrichment item used, the effects on agonism and manipulation of enrichment item were variable. To make informed management decisions about the psychological well-being of captive animals, it is important to objectively quantify and examine the influences on their behavior.

  3. 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.

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

    PubMed

    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.

  6. Selection Based on FOXA2 Expression Is Not Sufficient to Enrich for Dopamine Neurons From Human Pluripotent Stem Cells

    PubMed Central

    Aguila, Julio Cesar; Blak, Alexandra; van Arensbergen, Joris; Sousa, Amaia; Vázquez, Nerea; Aduriz, Ariane; Gayosso, Mayela; Lopez Mato, Maria Paz; Lopez de Maturana, Rakel; Hedlund, Eva; Sonntag, Kai-Christian

    2014-01-01

    Human embryonic and induced pluripotent stem cells are potential cell sources for regenerative approaches in Parkinson disease. Inductive differentiation protocols can generate midbrain dopamine neurons but result in heterogeneous cell mixtures. Therefore, selection strategies are necessary to obtain uniform dopamine cell populations. Here, we developed a selection approach using lentivirus vectors to express green fluorescent protein under the promoter region of FOXA2, a transcription factor that is expressed in the floor plate domain that gives rise to dopamine neurons during embryogenesis. We first validated the specificity of the vectors in human cell lines against a promoterless construct. We then selected FOXA2-positive neural progenitors from several human pluripotent stem cell lines, which demonstrated a gene expression profile typical for the ventral domain of the midbrain and floor plate, but failed to enrich for dopamine neurons. To investigate whether this was due to the selection approach, we overexpressed FOXA2 in neural progenitors derived from human pluripotent stem cell lines. FOXA2 forced expression resulted in an increased expression of floor plate but not mature neuronal markers. Furthermore, selection of the FOXA2 overexpressing fraction also failed to enrich for dopamine neurons. Collectively, our results suggest that FOXA2 is not sufficient to induce a dopaminergic fate in this system. On the other hand, our study demonstrates that a combined approach of promoter activation and lentivirus vector technology can be used as a versatile tool for the selection of a defined cell population from a variety of human pluripotent stem cell lines. PMID:25024431

  7. 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

  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. Increasing breeding behaviors in a captive colony of Northern Bald Ibis through conspecific acoustic enrichment.

    PubMed

    Clark, J Alan; Haseley, Alison; Van Genderen, Garry; Hofling, Mark; Clum, Nancy J

    2012-01-01

    The goal of this study was to increase reproductive behaviors in a captive colony of Northern Bald Ibis (Geronticus eremita) at the Bronx Zoo. The Northern Bald Ibis is classified as critically endangered by the IUCN, with only about 100 known breeding pairs in the wild. Our analysis of zoo breeding and colony size data confirmed earlier observations that small captive colonies of this species do not breed as well as larger colonies, possibly because of insufficient social cues. Using principles from social facilitation theory, we attempted to provide such social cues by presenting acoustic enrichment in the form of conspecific breeding vocalization playbacks. In May 2009, we tracked multiple breeding behaviors during playbacks and control periods. Although breeding behaviors increased in response to playbacks, the colony produced no eggs. We repeated this experiment in April 2010 using playbacks of higher quality recordings acquired from a semi-wild breeding colony of Northern Bald Ibis in Austria. Breeding behaviors again increased during playbacks. In addition, five pairs in this colony of 15 birds produced 13 eggs, and six chicks successfully fledged--the first reproductive success in this colony since 2007. The acoustic enrichment techniques we employed may encourage increased breeding activity in captive populations of colonial species as well as wild colonies with small populations.

  10. Isolation and enumeration of Campylobacter jejuni from poultry products by a selective enrichment method.

    PubMed

    Wesley, R D; Swaminathan, B; Stadelman, W J

    1983-11-01

    A direct selective enrichment procedure was developed for the isolation of Campylobacter jejuni from poultry products. The selective enrichment medium (ATB) consisted of (per liter) tryptose (20 g), yeast extract (2.5 g), sodium chloride (5 g), FBP supplement (ferrous sulfate [0.25 g], sodium metabisulfite [0.25 g], sodium pyruvate [0.25 g]), bicine (10 g), and agar (1 g). Hematin solution (6.25 ml; prepared by dissolving 0.032 g of bovine hemin in 10 ml of 0.15 N sodium hydroxide solution and autoclaving at 0.35 kg/cm2 for 30 min), rifampin (25 mg), cefsulodin (6.25 mg), and polymyxin B sulfate (20,000 IU) were added after the medium was sterilized. The pH was adjusted to 8.0. Samples were enriched in the above medium at 42 degrees C for 48 h under an atmosphere of 5% O2, 10% CO2, and 85% N2. Enrichment cultures were streaked on a plating medium composed of Brucella agar, hematin solution, FBP supplement, and the above antibiotics. Plates were incubated under the same conditions as above. Suspect colonies from the plates were confirmed to be C. jejuni by morphological examination, growth characteristics, and biochemical tests. The above method yielded 25 isolates of C. jejuni from 50 samples of retail cut-up chicken and chicken parts, whereas a more complex method involving filtration, centrifugation, selective enrichment under a flowing atmosphere, and membrane filtration yielded only 6 positives from the same samples. The new isolation procedure was particularly effective in isolating C. jejuni in the presence of large numbers of Pseudomonas aeruginosa.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6651294

  11. 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.

  12. Comparison of subtypes of Listeria monocytogenes isolates from naturally contaminated watershed samples using a combination of non-selective and selective enrichment methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two enrichment methods for Listeria monocytogenes using Immuno Magnetic Separation were tested to determine if they selected the same subtypes of isolates. Both methods included a non-selective enrichment and one included subculture in Fraser Broth. Naturally contaminated watershed samples from the ...

  13. 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.

  14. Calcium and vitamin D enriched diets increase and preserve vertebral mineral content in aging laboratory rats.

    PubMed

    Schapira, D; Linn, S; Sarid, M; Mokadi, S; Kabala, A; Silbermann, M

    1995-05-01

    To assess the long-term effect of vitamin D or calcium supplementation on the skeletal metabolism of aging laboratory rodents, 1.5-month-old female Wistar rats were fed with diets containing twice the concentration of vitamin D (group 2) and of calcium (group 3) as in the usual rat chow. Follow-up to 24 months of age did not show significant differences between the enriched-diet groups and the controls (group 1) in terms of the vertebral body weight and protein content. Significantly higher bone mineral contents were found in groups 2 and 3 than were found in controls, as revealed by an increased bone mineral density (BMD: +62%, group 2; +48%, group 3) and vertebral calcium content (+73%, group 2; +84%, group 3). The vertebral alkaline phosphatase enzymatic activity was significantly lower in the enriched diet groups than in controls (-47%, group 2; -45%, group 3). The ratio alkaline phosphatase/acid phosphatase activity was markedly reduced in groups 2 and 3 (-57% and -59%, respectively), which might indicate a diminished rate of bone turnover. The trabecular bone volume (BV/TV) decreased in all groups during senescence, being significantly elevated in group 3 as compared to controls. Vitamin D and calcium dietary supplementations increase the axial mineral bone content in laboratory rats and might reduce the bone turnover. Their influence on the trabecular bone volume has yet to be examined.

  15. Goat milk fat naturally enriched with conjugated linoleic acid increased lipoproteins and reduced triacylglycerol in rats.

    PubMed

    Rodrigues, Raphaela; Soares, Juliana; Garcia, Hugo; Nascimento, Claudenice; Medeiros, Maria; Bomfim, Marco; Medeiros, Maria Carmo; Queiroga, Rita

    2014-01-01

    Goat milk is source of different lipids, including conjugated linoleic acid (CLA). CLA reduces body fat and protect against cardiovascular diseases. In the present study fat from goat milk naturally enriched with CLA was used. Male Wistar rats were divided into three groups that received during a 10 week diet with different lipid sources: soybean oil (CON), coconut oil (CO) and goat milk fat naturally enriched with CLA (GM-CLA). We evaluated the effects of a GM-CLA on biochemistry parameters--high density lipoprotein (HDL), triacylglycerol (TAG), TAG/HDL ratio, total cholesterol and glucose, body weight and histopathological aspects of the intestine and liver. GM-CLA increased body weight from the second to the fifth week of the experiment compared to CON. Feed intake differed between the CON group and GM-CLA early in the first to third week of the experiments and later between the ninth and tenth week. The CLA-diet group showed increased levels of HDL, reduced levels of TAG and TAG/HDL ratio and no effect on LDL, but enhanced total cholesterol. Serum glucose of the GM-CLA group showed no difference from the control group. Thus, a GM-CLA diet promoted growth in young rats and acted as protector of cardiovascular function, but further studies are still needed to clarify these effects. PMID:24662092

  16. Long-term environmental enrichment leads to regional increases in neurotrophin levels in rat brain.

    PubMed

    Ickes, B R; Pham, T M; Sanders, L A; Albeck, D S; Mohammed, A H; Granholm, A C

    2000-07-01

    A number of studies have demonstrated that both morphological and biochemical indices in the brain undergo alterations in response to environmental influences. In previous work we have shown that rats raised in an enriched environmental condition (EC) perform better on a spatial memory task than rats raised in isolated conditions (IC). We have also found that EC rats have a higher density of immunoreactivity than IC rats for both low and high affinity nerve growth factor (NGF) receptors in the basal forebrain. In order to determine if these alterations were coupled with altered levels of neurotrophins in other brain regions as well, we measured neurotrophin levels in rats that were raised in EC or IC conditions. Rats were placed in the different environments at 2 months of age and 12 months later brain regions were dissected and analyzed for NGF, brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3) levels using Promega ELISA kits. We found that NGF and BDNF levels were increased in the cerebral cortex, hippocampal formation, basal forebrain, and hindbrain in EC animals compared to age-matched IC animals. NT-3 was found to be increased in the basal forebrain and cerebral cortex of EC animals as well. These findings demonstrate significant alterations in NGF, BDNF, and NT-3 protein levels in several brain regions as a result of an enriched versus an isolated environment and thus provide a possible biochemical basis for behavioral and morphological alterations that have been found to occur with a shifting environmental stimulus.

  17. 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.

  18. Proportion of soft tissue in selected bone cuts fed primarily as enrichments to large carnivores.

    PubMed

    Felicetti, Laura; Kearney, Celeste C; Woodward, Lloyd; Dierenfeld, Ellen S

    2008-03-01

    Zoos often offer large bones or cuts of meat containing bone (bone cuts) to carnivores to provide oral stimulation and behavioral enrichment. Because of its abrasive action, the act of chewing on a bone can increase the oral health of large felids as well as provide an enriching activity. Unfortunately, because the quantity of edible tissue on the bones is usually unknown, when feeding these cuts one can easily miscalculate an animal's caloric and nutrient intake. To fully comprehend the contribution of bones as a dietary item as opposed to an enrichment item, we removed the soft tissue from a total of 70 samples, representing 14 types of bone cuts commonly used in managed carnivore feeding programs. Across types of cuts, soft tissue averaged 50% of wet weight, with pork knuckles averaging the lowest (23%) and horse shanks the greatest (74%) percent soft tissue. Zoo Biol 27:154-158, 2008. (c) 2008 Wiley-Liss, Inc.

  19. Whole-Exome Enrichment with the Agilent SureSelect Human All Exon Platform.

    PubMed

    Chen, Rui; Im, Hogune; Snyder, Michael

    2015-07-01

    There are multiple platforms available for whole-exome enrichment and sequencing (WES). This protocol is based on the Agilent SureSelect Human All Exon platform, which targets ∼50 Mb of the human exonic regions. The SureSelect system uses ∼120-base RNA probes to capture known coding DNA sequences (CDS) from the NCBI Consensus CDS Database as well as other major RNA coding sequence databases, such as Sanger miRBase. The protocol can be performed at the benchside without the need for automation, and the resulting library can be used for targeted next-generation sequencing on an Illumina HiSeq 2000 sequencer.

  20. 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.

  1. 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.

  2. Droplet enrichment factors of pigmented and nonpigmented Serratia marcescens: possible selective function for prodigiosin.

    PubMed

    Burger, S R; Bennett, J W

    1985-08-01

    Drops produced by bursting bubbles provide a mechanism for the water-to-air transfer and concentration of matter. Bacteria can adsorb to air bubbles rising through bacterial suspensions and enrich the drops formed by the bubbles upon breaking, creating atmospheric biosols which function in dispersal. This bacterial enrichment can be quantified as an enrichment factor (EF), calculated as the ratio of the concentration of bacteria in the drop to that of the bulk bacterial suspension. Bubbles were produced in suspensions of pigmented (prodigiosin-producing) and nonpigmented cultures of Serratia marcescens. EFs for pigmented cultures were greater than EFs for nonpigmented cells. Pigmented cells appeared hydrophobic based on their partitioning in two-phase systems of polyethylene glycol 6000 and dextran T500. The surface hydrophobicity of pigmented cells may result from the hydrophobic nature of prodigiosin and could account for the greater ability of these bacteria to adsorb to air bubbles and enrich airborne droplets. Enhancement of the aerosolization of S. marcescens may be a selective function of the bacterial secondary metabolite prodigiosin.

  3. Droplet enrichment factors of pigmented and nonpigmented Serratia marcescens: possible selective function for prodigiosin.

    PubMed Central

    Burger, S R; Bennett, J W

    1985-01-01

    Drops produced by bursting bubbles provide a mechanism for the water-to-air transfer and concentration of matter. Bacteria can adsorb to air bubbles rising through bacterial suspensions and enrich the drops formed by the bubbles upon breaking, creating atmospheric biosols which function in dispersal. This bacterial enrichment can be quantified as an enrichment factor (EF), calculated as the ratio of the concentration of bacteria in the drop to that of the bulk bacterial suspension. Bubbles were produced in suspensions of pigmented (prodigiosin-producing) and nonpigmented cultures of Serratia marcescens. EFs for pigmented cultures were greater than EFs for nonpigmented cells. Pigmented cells appeared hydrophobic based on their partitioning in two-phase systems of polyethylene glycol 6000 and dextran T500. The surface hydrophobicity of pigmented cells may result from the hydrophobic nature of prodigiosin and could account for the greater ability of these bacteria to adsorb to air bubbles and enrich airborne droplets. Enhancement of the aerosolization of S. marcescens may be a selective function of the bacterial secondary metabolite prodigiosin. PMID:3901922

  4. Tweezing-adsorptive bubble separation. Analytical method for the selective and high enrichment of metalloenzymes.

    PubMed

    Gerken, Birte M; Wattenbach, Carsten; Linke, Diana; Zorn, Holger; Berger, Ralf G; Parlar, Harun

    2005-10-01

    A novelly developed tweezing-adsorptive bubble separation (ABS) method for the enrichment of metalloenzymes (laccase C and horseradish peroxidase) is introduced. The method is based on the chelation of the enzymes' active center and can also be applied for analysis. N-(2-acetamido)iminodiacetic acid served as a chelator and was synthesized with an octyl unit to become ADA-C8. Laccase was enriched 13.3-fold (66.31% recovery) and HPOX 17.8-fold (85.34%) without a significant loss of enzymatic activity. To prove that the entire enzyme is tweezed at the active center, ABS trials were done using ADA-C8 already complexed with Cu2+ and Fe3+. As only marginal enrichment occurred (ER laccase, 0.17; ER HPOX, 0.44), no chelating effect was concluded. It was determined how the chelation toward the active center was directed by applying other chelators such as EDTA, NTA, N,N-dimethylaminoglycine, oxalic acid, malonic acid, adipinic acid, and tripropylamine, which are similar in structure to ADA-C8. The results concluded that the chelation is 3-fold coordinated on the type 1 copper center of laccase, whereas that of HPOX only 1-fold at Fe3+ and additionally at the cationic amino acid arginine, which is also located at the active center. Tweezing-ABS has been proven to selectively and effectively enrich metalloenzymes.

  5. 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.

  6. 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

  7. 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.

  8. Selective enrichment media bias the types of Salmonella enterica strains isolated from mixed strain cultures and complex enrichment broths.

    PubMed

    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.

  9. 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.

  10. 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

  11. 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

  12. [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.

  13. [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

  14. Positive selection of gene-modified cells increases the efficacy of pancreatic cancer suicide gene therapy.

    PubMed

    Martinez-Quintanilla, Jordi; Cascallo, Manel; Gros, Alena; Fillat, Cristina; Alemany, Ramon

    2009-11-01

    Thymidine kinase (TK)-mediated suicide gene therapy has been considered for the treatment of pancreatic cancer. However, despite a bystander effect, the proportion of transduced tumor cells has proven too low to result in efficacy. We propose the use of a drug-selectable marker (MDR1) to enrich TK-expressing cells using chemotherapy. This enrichment or positive selection phase may increase the efficacy of suicide gene therapy. To test this strategy, we generated stable NP18MDR/TK-GFP transfectants and showed docetaxel resistance in vivo. Mixed tumors of MDR/TK-expressing cells and parental NP18 cells were established and docetaxel was used to increase the proportion of TK-expressing cells. After this positive selection phase, suicide gene therapy with ganciclovir was applied. Upon positive selection, the proportion of TK-expressing cells increased from 4% to 22%. Subsequent suicide gene therapy was more effective compared with a control group without positive selection. Starting with 10% of TK-expressing cells the positive-negative selection strategy completely inhibited tumor growth. Taken together, these results suggest that a positive-negative selection strategy based on MDR and TK genes represents an efficient way to increase the proportion of TK-expressing cells in the tumor and the efficacy of TK-mediated suicide gene therapy.

  15. 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.

  16. 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

  17. 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

  18. 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

  19. Selective Evolution of Ligands by Exponential Enrichment to Identify RNA Aptamers against Shiga Toxins

    PubMed Central

    Challa, Sreerupa; Tzipori, Saul; Sheoran, Abhineet

    2014-01-01

    Infection with Shiga toxin- (Stx-) producing E. coli causes life threatening hemolytic uremic syndrome (HUS), a leading cause of acute renal failure in children. Of the two antigenically distinct toxins, Stx1 and Stx2, Stx2 is more firmly linked with the development of HUS. In the present study, selective evolution of ligands by exponential enrichment (SELEX) was used in an attempt to identify RNA aptamers against Stx1 and Stx2. After 5 rounds of selection, significant enrichment of aptamer pool was obtained against Stx2, but not against Stx1, using a RNA aptamer library containing 56 random nucleotides (N56). Characterization of individual aptamer sequences revealed that six unique RNA aptamers (mA/pC, mB/pA, mC, mD, pB, and pD) recognized Stx2 in a filter binding assay. None of these aptamers bound Stx1. Aptamers mA/pC, mB/pA, mC, and mD, but not pB and pD, partially blocked binding of Alexa 488-labeled Stx2 with HeLa cells in a flow cytometry assay. However, none of the aptamers neutralized Stx2-mediated cytotoxicity and death of HeLa cells. PMID:24839553

  20. Effect of Model Sorptive Phases on Phenanthrene Biodegradation: Molecular Analysis of Enrichments and Isolates Suggests Selection Based on Bioavailability

    PubMed Central

    Friedrich, M.; Grosser, R. J.; Kern, E. A.; Inskeep, W. P.; Ward, D. M.

    2000-01-01

    Reduced bioavailability of nonpolar contaminants due to sorption to natural organic matter is an important factor controlling biodegradation of pollutants in the environment. We established enrichment cultures in which solid organic phases were used to reduce phenanthrene bioavailability to different degrees (R. J. Grosser, M. Friedrich, D. M. Ward, and W. P. Inskeep, Appl. Environ. Microbiol. 66:2695–2702, 2000). Bacteria enriched and isolated from contaminated soils under these conditions were analyzed by denaturing gradient gel electrophoresis (DGGE) and sequencing of PCR-amplified 16S ribosomal DNA segments. Compared to DGGE patterns obtained with enrichment cultures containing sand or no sorptive solid phase, different DGGE patterns were obtained with enrichment cultures containing phenanthrene sorbed to beads of Amberlite IRC-50 (AMB), a weak cation-exchange resin, and especially Biobead SM7 (SM7), a polyacrylic resin that sorbed phenanthrene more strongly. SM7 enrichments selected for mycobacterial phenanthrene mineralizers, whereas AMB enrichments selected for a Burkholderia sp. that degrades phenanthrene. Identical mycobacterial and Burkholderia 16S rRNA sequence segments were found in SM7 and AMB enrichment cultures inoculated with contaminated soil from two geographically distant sites. Other closely related Burkholderia sp. populations, some of which utilized phenanthrene, were detected in sand and control enrichment cultures. Our results are consistent with the hypothesis that different phenanthrene-utilizing bacteria inhabiting the same soils may be adapted to different phenanthrene bioavailabilities. PMID:10877758

  1. Environmental enrichment increases the GFAP+ stem cell pool and reverses hypoxia-induced cognitive deficits in juvenile mice.

    PubMed

    Salmaso, Natalina; Silbereis, John; Komitova, Mila; Mitchell, Patrick; Chapman, Katherine; Ment, Laura R; Schwartz, Michael L; Vaccarino, Flora M

    2012-06-27

    Premature children born with very low birth weight (VLBW) can suffer chronic hypoxic injury as a consequence of abnormal lung development and cardiovascular abnormalities, often leading to grave neurological and behavioral consequences. Emerging evidence suggests that environmental enrichment improves outcome in animal models of adult brain injury and disease; however, little is known about the impact of environmental enrichment following developmental brain injury. Intriguingly, data on socio-demographic factors from longitudinal studies that examined a number of VLBW cohorts suggest that early environment has a substantial impact on neurological and behavioral outcomes. In the current study, we demonstrate that environmental enrichment significantly enhances behavioral and neurobiological recovery from perinatal hypoxic injury. Using a genetic fate-mapping model that allows us to trace the progeny of GFAP+ astroglial cells, we show that hypoxic injury increases the proportion of astroglial cells that attain a neuronal fate. In contrast, environmental enrichment increases the stem cell pool, both through increased stem cell proliferation and stem cell survival. In mice subjected to hypoxia and subsequent enrichment there is an additive effect of both conditions on hippocampal neurogenesis from astroglia, resulting in a robust increase in the number of neurons arising from GFAP+ cells by the time these mice reach full adulthood.

  2. Stearidonic acid-enriched soybean oil increased the omega-3 index, an emerging cardiovascular risk marker.

    PubMed

    Harris, William S; Lemke, Shawna L; Hansen, Susan N; Goldstein, Daniel A; DiRienzo, Maureen A; Su, Hong; Nemeth, Margaret A; Taylor, Mary L; Ahmed, Gulam; George, Cherian

    2008-09-01

    A plant source of omega-3 fatty acid (FA) that can raise tissue eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA) is needed. A soybean oil (SBO) containing approximately 20% stearidonic acid [SDA; the delta-6 desaturase product of alpha-linolenic acid (ALA)] derived from genetically modified soybeans is under development. This study compared the effects of EPA to SDA-SBO on erythrocyte EPA+DHA levels (the omega-3 index). Overweight healthy volunteers (n=45) were randomized to SDA-SBO (24 ml/day providing approximately 3.7 g SDA) or to regular SBO (control group) without or with EPA ethyl esters (approximately 1 g/day) for 16 weeks. Serum lipids, blood pressure, heart rate, platelet function and safety laboratory tests were measured along with the omega-3 index. A per-protocol analysis was conducted on 33 subjects (11 per group). Compared to baseline, average omega-3 index levels increased 19.5% in the SDA group and 25.4% in the EPA group (p<0.05 for both, vs. control). DHA did not change in any group. Relative to EPA, SDA increased RBC EPA with about 17% efficiency. No other clinical endpoints were affected by SDA or EPA treatment (vs. control). In conclusion, SDA-enriched SBO significantly raised the omega-3 index. Since EPA supplementation has been shown to raise the omega-3 index and to lower risk for cardiac events, SDA-SBO may be a viable plant-based alternative for providing meaningful intakes of cardioprotective omega-3 FAs.

  3. 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

  4. 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

  5. SHAPE Selection (SHAPES) enrich for RNA structure signal in SHAPE sequencing-based probing data.

    PubMed

    Poulsen, Line Dahl; Kielpinski, Lukasz Jan; Salama, Sofie R; Krogh, Anders; Vinther, Jeppe

    2015-05-01

    Selective 2' Hydroxyl Acylation analyzed by Primer Extension (SHAPE) is an accurate method for probing of RNA secondary structure. In existing SHAPE methods, the SHAPE probing signal is normalized to a no-reagent control to correct for the background caused by premature termination of the reverse transcriptase. Here, we introduce a SHAPE Selection (SHAPES) reagent, N-propanone isatoic anhydride (NPIA), which retains the ability of SHAPE reagents to accurately probe RNA structure, but also allows covalent coupling between the SHAPES reagent and a biotin molecule. We demonstrate that SHAPES-based selection of cDNA-RNA hybrids on streptavidin beads effectively removes the large majority of background signal present in SHAPE probing data and that sequencing-based SHAPES data contain the same amount of RNA structure data as regular sequencing-based SHAPE data obtained through normalization to a no-reagent control. Moreover, the selection efficiently enriches for probed RNAs, suggesting that the SHAPES strategy will be useful for applications with high-background and low-probing signal such as in vivo RNA structure probing.

  6. 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

  7. 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.

  8. 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.

  9. 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

  10. Selection for niche differentiation in plant communities increases biodiversity effects.

    PubMed

    Zuppinger-Dingley, Debra; Schmid, Bernhard; Petermann, Jana S; Yadav, Varuna; De Deyn, Gerlinde B; Flynn, Dan F B

    2014-11-01

    In experimental plant communities, relationships between biodiversity and ecosystem functioning have been found to strengthen over time, a fact often attributed to increased resource complementarity between species in mixtures and negative plant-soil feedbacks in monocultures. Here we show that selection for niche differentiation between species can drive this increasing biodiversity effect. Growing 12 grassland species in test monocultures and mixtures, we found character displacement between species and increased biodiversity effects when plants had been selected over 8 years in species mixtures rather than in monocultures. When grown in mixtures, relative differences in height and specific leaf area between plant species selected in mixtures (mixture types) were greater than between species selected in monocultures (monoculture types). Furthermore, net biodiversity and complementarity effects were greater in mixtures of mixture types than in mixtures of monoculture types. Our study demonstrates a novel mechanism for the increase in biodiversity effects: selection for increased niche differentiation through character displacement. Selection in diverse mixtures may therefore increase species coexistence and ecosystem functioning in natural communities and may also allow increased mixture yields in agriculture or forestry. However, loss of biodiversity and prolonged selection of crops in monoculture may compromise this potential for selection in the longer term.

  11. 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

  12. Maltodextrin-modified magnetic microspheres for selective enrichment of maltose binding proteins.

    PubMed

    Zheng, Jin; Ma, Chongjun; Sun, Yangfei; Pan, Miaorong; Li, Li; Hu, Xiaojian; Yang, Wuli

    2014-03-12

    In this work, maltodextrin-modified magnetic microspheres Fe3O4@SiO2-Maltodextrin (Fe3O4@SiO2-MD) with uniform size and fine morphology were synthesized through a facile and low-cost method. As the maltodextrins on the surface of microspheres were combined with maltose binding proteins (MBP), the magnetic microspheres could be applied to enriching standard MBP fused proteins. Then, the application of Fe3O4@SiO2-MD in one-step purification and immobilization of MBP fused proteins was demonstrated. For the model protein we examined, Fe3O4@SiO2-MD showed excellent binding selectivity and capacity against other Escherichia coli proteins in the crude cell lysate. Additionally, the maltodextrin-modified magnetic microspheres can be recycled for several times without significant loss of binding capacity.

  13. Tetraspan microdomains distinct from lipid rafts enrich select peptide-MHC class II complexes.

    PubMed

    Kropshofer, H; Spindeldreher, S; Röhn, T A; Platania, N; Grygar, C; Daniel, N; Wölpl, A; Langen, H; Horejsi, V; Vogt, A B

    2002-01-01

    Complexes of peptide and major histocompatibility complex (MHC) class II are expressed on the surface of antigen-presenting cells but their molecular organization is unknown. Here we show that subsets of MHC class II molecules localize to membrane microdomains together with tetraspan proteins, the peptide editor HLA-DM and the costimulator CD86. Tetraspan microdomains differ from other membrane areas such as lipid rafts, as they enrich MHC class II molecules carrying a selected set of peptide antigens. Antigen-presenting cells deficient in tetraspan microdomains have a reduced capacity to activate CD4+ T cells. Thus, the organization of uniformly loaded peptide-MHC class II complexes in tetraspan domains may be a very early event that determines both the composition of the immunological synapse and the quality of the subsequent T helper cell response.

  14. 4-Mercaptophenylboronic acid functionalized graphene oxide composites: Preparation, characterization and selective enrichment of glycopeptides.

    PubMed

    Jiang, Bo; Qu, Yanyan; Zhang, Lihua; Liang, Zhen; Zhang, Yukui

    2016-03-17

    Selective enrichment and isolation of glycopeptides from complex biological samples was indispensable for mass spectrometry (MS)-based glycoproteomics, however, it remained a great challenge due to the low abundance of glycoproteins and the ion suppression of non-glycopeptides. In this work, 4-mercaptophenylboronic acid functionalized graphene oxide composites were synthesized via loading gold nanoparticles on polyethylenimine modified graphene oxide surface, followed by 4-mercaptophenylboronic acid immobilization by the formation of Au-S bonding (denoted as GO/PEI/Au/4-MPB composites). The composites showed highly specific and efficient capture of glycopeptides due to their excellent hydrophilicity and abundant boronic acid groups. The composites could selectively capture the glycopeptides from the mixture of glycopeptides and nonglycopeptides, even when the amounts of non-glycopeptides were 100 times more than glycopeptides. Compared with commercial meta-amino phenylboronic acid agarose, the composites showed better selectivity when the sample was decreased to 10 ng. These results clearly verified that the GO/PEI/Au/4-MPB composites might be a promising material for glycoproteomics analysis.

  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. Enriched environment increases myelinated fiber volume and length in brain white matter of 18-month female rats.

    PubMed

    Yang, Shu; Lu, Wei; Zhou, De-shan; Tang, Yong

    2015-04-23

    Cognition and memory decline with normal aging, which could be partly attributed to the degeneration of brain white matter. Previous studies demonstrated that exposure to an enriched environment (EE) could protect cognition and memory from aging. However, if or how EE might affect the brain white matter has not been thoroughly investigated. In the current study, 24 middle-aged (14-month-old) female Sprague -Dawley (SD) rats were randomly assigned to EE or standard environment (SE) for 4 months. At the end of the environment intervention, the Morris water maze tests were performed. Then, 5 rats were randomly selected from each group for stereological assessment of the brain white matter and its myelinated fibers. The results revealed that middle-aged rats living in EE displayed better spatial learning than SE controls. The white matter volume was 124.6 ± 7.8mm(3) in EE rats, which was significantly enlarged compared with 84.8 ± 3.4mm(3) in SE rats. Likewise, the myelinated fiber volume was markedly increased from 56.6 ± 1.7 mm(3) in SE rats to 87.2 ± 9.0mm(3) in EE rats; so was the myelinated fiber length from 83.5 ± 6.6 km in SE rats to 119.0 ± 10.0 km in EE rats. Our data suggested that EE could protect brain white matter and its myelinated fibers of female rats at middle age.

  17. 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)

  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.

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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

  4. Highly efficient enrichment of porcine cells with deletions induced by CRISPR/Cas9 using dual fluorescence selection.

    PubMed

    He, Zuyong; Shi, Xuan; Du, Baozhu; Qin, Yufeng; Cong, Peiqing; Chen, Yaosheng

    2015-11-20

    Production of nuclear donor cells with a high percentage of desired modifications is a critical step in the successful generation of genetically modified pigs through somatic cell nuclear transfer (SCNT). The CRISPR/Cas9 system has been used for efficient modification of the nuclear DNA in eukaryotic cells, including porcine cells. However, in vitro modified cells are often phenotypically indistinguishable from unmodified cells, hampering their enrichment. Here we investigate a dual fluorescence selection system for the efficient enrichment of porcine embryonic fibroblasts (PEFs) with CRISPR/Cas9-induced chromosomal deletions. Enrichment of cells with 170 bp deletions reached a frequency of 74%, whilst enrichment of cells with a larger 5 kb deletions achieved a frequency of 46%. This demonstrates the utility of a dual fluorescence reporter as an attractive tool for improving the efficiency of generating genome edited pigs.

  5. Selective Enrichment of Two Different Types of Nitrospira-like Nitrite-oxidizing Bacteria from a Wastewater Treatment Plant

    PubMed Central

    Fujitani, Hirotsugu; Aoi, Yoshiteru; Tsuneda, Satoshi

    2013-01-01

    Nitrification is an important step in nitrogen removal in biological wastewater treatment processes. Recently, Nitrospira have been recognized as the numerically dominant nitrite-oxidizing bacterial genus primarily responsible for the second step of aerobic nitrification; however, Nitrospira usually resist cultivation under laboratory conditions and only one species enriched from activated sludge has been described. In this study, a novel enrichment method for Nitrospira was successfully developed using continuous feeding bioreactors. By controlling nitrite concentrations strictly in the bioreactor at low levels below 10 mg-N L−1, coexisting members of sublineages I and II of the genus Nitrospira were enriched selectively. The maximum ratios of sublineages I and II to total microbial cells achieved 88.3% and 53.8%, respectively. This enrichment method is potentially applicable to other uncultured Nitrospira. PMID:23657014

  6. Positive affect increases the breadth of attentional selection

    PubMed Central

    Rowe, G.; Hirsh, J. B.; Anderson, A. K.

    2007-01-01

    The present study examined the thesis that positive affect may serve to broaden the scope of attentional filters, reducing their selectivity. The effect of positive mood states was measured in two different cognitive domains: semantic search (remote associates task) and visual selective attention (Eriksen flanker task). In the conceptual domain, positive affect enhanced access to remote associates, suggesting an increase in the scope of semantic access. In the visuospatial domain, positive affect impaired visual selective attention by increasing processing of spatially adjacent flanking distractors, suggesting an increase in the scope of visuospatial attention. During positive states, individual differences in enhanced semantic access were correlated with the degree of impaired visual selective attention. These findings demonstrate that positive states, by loosening the reins on inhibitory control, result in a fundamental change in the breadth of attentional allocation to both external visual and internal conceptual space. PMID:17182749

  7. 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.

  8. Combination of selective enrichment and MALDI-TOF MS for rapid detection of Streptococcus agalactiae colonisation of pregnant women.

    PubMed

    Ábrók, Marianna; Arcson, Ágnes; Lázár, Andrea; Urbán, Edit; Deák, Judit

    2015-07-01

    Sample preparation was optimized for MALDI-TOF MS directly from selective enrichment broth to detect Streptococcus agalactiae. The method was tested on 100 vaginal samples of pregnant women; positive and negative predictive values were 100 and 91%, respectively. If it indicates positivity, colonisation can be reported 18-24h after sample collection.

  9. New Feature Observed in the Raman Resonance Excitation Profiles of (6 , 5) -Enriched, Selectively Bundled SWCNTs

    NASA Astrophysics Data System (ADS)

    Hight Walker, A. R.; Simpson, J. R.; Roslyak, O.; Haroz, E.; Telg, H.; Duque, J. G.; Crochet, J. J.; Piryatinski, A.; Doorn, S. K.

    Understanding the photophysics of exciton behavior in single wall carbon nanotube (SWCNT) bundles remains important for opto-electronic device applications. We report resonance Raman spectroscopy (RRS) measurements on (6 , 5) -enriched SWCNTs, dispersed in aqueous solutions and separated using density gradient ultracentrifugation into fractions of increasing bundling. Near-IR to UV absorption spectroscopy shows a redshift and broadening of the main excitonic transitions with increasing bundling. A continuously tunable dye laser coupled to a triple-grating spectrometer affords measurement of Raman resonance excitation profiles (REPs) over a range of wavelengths covering the (6 , 5) -E22 range (505 to 585) nm. REPs of both the radial breathing mode (RBM) and G-band reveal a redshifting and broadening of the (6 , 5) E22 transition energy with increasing bundling. Additionally, we observe an unexpected peak in the REP of bundled SWCNTs, which is shifted lower in energy than the main E22 and is anomalously narrow. We compare these observations to a theoretical model that examines the origin of this peak in relation to bundle polarization-enhanced exciton response.

  10. Porous concrete block as an environmental enrichment device increases activity of laying hens in cages.

    PubMed

    Holcman, A; Gorjanc, G; Stuhec, I

    2008-09-01

    The purpose of this study was to consider the influence of simple and cheap environmental enrichment such as porous concrete on the behavior of laying hens in conventional cages. Forty brown laying hens were housed in individual wire mesh cages: 20 in experimental cages with porous concrete block provided for pecking and 20 in a control group without concrete block provided. Porous concrete block (5 cm length x 5 cm width x 5 cm height) was mounted on the side wall at the height of the hen's head. Behavior was studied from 42 to 48 wk of age. A group of 8 hens was filmed for 24 h, and the camera was moved each day so that all 40 hens were recorded over 5 d each wk. Videotaping was performed in wk 1, 3, 5, and 7 of the experiment. States (long-term behavior) were observed with 5-min interval recording (feeding, preening, resting, and remaining inactive), whereas events (short-term activities) were observed with instantaneous recording (drinking, pecking concrete, pecking neighbors, pecking cage, and attempting to escape). Data were analyzed with generalized linear mixed model with binomial distribution for states, and Poisson distribution for events. Monte Carlo Markov Chain methods were used to estimate model parameters. Because posterior distributions of quantities of interest were skewed, medians and standard errors are reported. Hens in experimental cages were more active in long-term behavior than controls (64.9 +/- 1.9 and 59.3 +/- 1.9% of the light period, respectively). Correspondingly, hens in the control group showed more long-term inactivity. In addition to pecking the porous concrete block, hens in experimental cages also showed other short-term activities with greater frequency (4.10 +/- 0.31 and 3.51 +/- 0.25 events per h, respectively). Our hypothesis that hens in enriched cages would have a greater level of activity was confirmed. Provision of a piece of porous concrete block as a pecking substrate enriched the environment of the birds at negligible

  11. 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

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

    DOE PAGES

    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

  13. 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

  14. 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.

  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. Ciprofloxacin residues in municipal biosolid compost do not selectively enrich populations of resistant bacteria.

    PubMed

    Youngquist, Caitlin P; Liu, Jinxin; Orfe, Lisa H; Jones, Stephen S; Call, Douglas R

    2014-12-01

    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.

  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.

  18. 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.

  19. Selection by parasites may increase host recombination frequency.

    PubMed

    Fischer, O; Schmid-Hempel, P

    2005-06-22

    Meiotic recombination destroys successful genotypes and it is therefore thought to evolve only under a very limited set of conditions. Here, we experimentally show that recombination rates across two linkage groups of the host, the red flour beetle Tribolium castaneum, increase with exposure to the microsporidian parasite, Nosema whitei, particularly when parasites were allowed to coevolve with their hosts. Selection by randomly varied parasites resulted in smaller effects, while directional selection for insecticide resistance initially reduced recombination slightly. These results, at least tentatively, suggest that short-term benefits of recombination--and thus the evolution of sex--may be related to parasitism.

  20. Construction of libraries enriched for sequence repeats and jumping clones, and hybridization selection for region-specific markers

    SciTech Connect

    Kandpal, R.P.; Kandpal, G.; Weissman, S.M. )

    1994-01-04

    The authors describe a simple and rapid method for constructing small-insert genomic libraries highly enriched for dimeric, trimeric, and tetrameric nucleotide repeat motifs. The approach involves use of DNA inserts recovered by PCR amplification of a small-insert sonicated genomic phage library or by a single-primer PCR amplification of Mbo I-digested and adaptor-ligated genomic DNA. The genomic DNA inserts are heat denatured and hybridized to a biotinylated oligonucleotde. The biotinylated hybrids are retained on a Vectrex-avidin matrix and eluted specifically. The eluate is PCR amplified and cloned. More than 90% of the clones in a library enriched for (CA)[sub n] microsatellites with this approach contained clones with inserts containing CA repeats. They have also used this protocol for enrichment of (CAG)[sub n] and (AGAT)[sub n] sequence repeats and for Not I jumping clones. They have used the enriched libraries with an adaptation of the cDNA selection method to enrich for repeat motifs encoded in yeast artificial chromosomes.

  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. Highly efficient and selective enrichment of glycopeptides using easily synthesized magG/PDA/Au/l-Cys composites.

    PubMed

    Wu, Runqing; Li, Lanting; Deng, Chunhui

    2016-05-01

    Highly selective and efficient enrichment of glycopeptides from complex biological samples is necessary. In this study, novel zwitterionic hydrophilic polydopamine-coated magnetic graphene composites (magG/PDA/Au/l-Cys) were synthesized and applied to the enrichment of glycopeptides. The size, morphology, and composition of magG/PDA/Au/l-Cys composites were investigated by transmission electron microscopy, scanning electron microscopy, FT-infrared spectroscopy, and X-ray diffraction. The composites possessed a number of desirable characteristics, including good biocompatibility easy separation property and excellent hydrophilicity. By virtue of the features contributed by different ingredients, the prepared composites demonstrated superior performance for glycopeptide enrichment with high sensitivity (0.1 fmol), efficiency, selectivity (1:100), and repeatability (at least ten times). In addition, the composites were successfully applied to the enrichment of glycopeptides from human serum and 40 unique N-glycosylation peptides from 31 different N-linked glycoproteins were identified. The superior hydrophilic material is of great potential for the analysis of glycoproteins.

  3. 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.

  4. 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

  5. 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

  6. Metal Oxide-Based Selective Enrichment Combined with Stable Isotope Labeling-Mass Spectrometry Analysis for Profiling of Ribose Conjugates.

    PubMed

    Chu, Jie-Mei; Qi, Chu-Bo; Huang, Yun-Qing; Jiang, Han-Peng; Hao, Yan-Hong; Yuan, Bi-Feng; Feng, Yu-Qi

    2015-07-21

    -SIL-LC-DNLS-MS strategy combines the selective enrichment, stable isotope labeling, and double neutral loss scan - MS analysis, which therefore can efficiently minimize false positive results, facilitate the relative quantification, and notably increase the numbers of identified ribose conjugates in biological fluids samples. Taken together, this study established a promising strategy for the effective profiling of urinary modified ribonucleosides, and simultaneous evaluation of the contents change of multiple modified ribonucleosides should provide more accurate and conclusive results for the use of urinary modified ribonucleosides as indicators of cancers.

  7. 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.

  8. Facile synthesis of titania nanoparticles coated carbon nanotubes for selective enrichment of phosphopeptides for mass spectrometry analysis.

    PubMed

    Yan, Yinghua; Lu, Jin; Deng, Chunhui; Zhang, Xiangmin

    2013-03-30

    In this work, titania nanoparticles coated carbon nanotubes (denoted as CNTs/TiO2 composites) were synthesized through a facile but effective solvothermal reaction using titanium isopropoxide as the titania source, isopropyl alcohol as the solvent and as the basic catalyst in the presence of hydrophilic carbon nanotubes. Characterizations using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicate that the CNTs/TiO2 composites consist of CNT core and a rough outer layer formed by titania nanoparticles (5-10nm). Measurements using wide angle X-ray diffraction (WAXRD), zeta potential and N2 sorption reveal that the titania shell is formed by anatase titania nanoparticles, and the composites have a high specific surface area of about 104 m(2)/g. By using their high surface area and affinity to phosphopeptides, the CNTs/TiO2 composites were applied to selectively enrich phosphopeptides for mass spectrometry analysis. The high selectivity and capacity of the CNTs/TiO2 composites have been demonstrated by effective enrichment of phosphopeptides from digests of phosphoprotein, protein mixtures of β-casein and bovine serum albumin, human serum and rat brain samples. These results foresee a promising application of the novel CNTs/TiO2 composites in the selective enrichment of phosphopeptides.

  9. Early enriched environment induces an increased conversion of proBDNF to BDNF in the adult rat's hippocampus.

    PubMed

    Cao, Wenyu; Duan, Juan; Wang, Xueqin; Zhong, Xiaolin; Hu, Zhaolan; Huang, Fulian; Wang, Hongtao; Zhang, Juan; Li, Fang; Zhang, Jianyi; Luo, Xuegang; Li, Chang-Qi

    2014-05-15

    An enriched environment has been shown to influence brain plasticity and function by involving the action of brain-derived neurotrophic factor (BDNF). BDNF, which is synthesized as a precursor molecule (proBDNF) that undergoes proteolytic cleavage, plays an important role in synaptic plasticity and contributes to several brain functions such as memory, learning, and behavior. The neurotrophins and proneurotrophins often play opposite roles in the brain, suggesting that proteolytic cleavage of proneurotrophins controls the action of neurotrophins. However, few studies have focused on the expression and cleavage of proBDNF after exposure to an enriched environment. Our study aimed to explore the effects of an early-enriched environment on the conversion of proBDNF to BDNF in the adult rats' hippocampus. We found that there was no difference in the expression of proBDNF in the hippocampus between the SE (standard environment) and EE (enriched environment) rats, but a significantly increased BDNF protein level was found in the EE rats. Thus, a remarkably enhanced ratio of BDNF to proBDNF (BDNF/proBDNF) was observed in the EE rats. In addition, the EE resulted in a remarkably up-regulated matrix metalloproteinase-9 (MMP-9) in the hippocampus, which played a key role in converting proBDNF to BDNF in the extracellular space. Furthermore, the expression of synapse-related proteins (NR1 and NR2A) was analyzed, and the results indicated that EE could significantly increase the expression of NR1 and NR2A in the hippocampus. In addition, the behavioral results showed that EE reduced anxiety-like behavior in the elevated-plus maze test and reduced immobility time in the forced swimming test. Moreover, the EE resulted in an increased preference for sucrose compared to the SE. These results suggested that the EE up-regulated MMP-9 levels within the hippocampus, which might facilitate the conversion of proBDNF to BDNF, thereby contributing to the long lasting alterations of

  10. In vitro selection of DNAs with an increased propensity to form small circles.

    PubMed

    Rosanio, Gabriel; Widom, Jonathan; Uhlenbeck, Olke C

    2015-06-01

    A protocol was devised to select for DNA molecules that efficiently form circles from a library of 126 base pair DNAs containing 90 randomized base pairs. After six rounds of selection, individual molecules from the library showed 20- to 100-fold greater j-factors compared with the starting library, validating the selection protocol. High-throughput sequencing revealed a sinusoidal pattern of enrichment and de-enrichment of A/T dinucleotides in the random region with a 10.4 base pair period associated with the helicity of DNA. A similar, but more moderate pattern of C/G dinucleotides was offset by precisely half a helical turn. While C/G dinucleotide enrichments were evenly distributed, A/T dinucleotide enrichments displayed a preference to cluster in individual DNA molecules. The most highly enriched 10 base pair sequences in the random region contained adjacent blocks of A/T and C/G trinucleotides present in some, but not all, rapidly cyclizing molecules. The phased dinucleotide enrichments closely match those present in accurately mapped yeast nucleosomes, confirming the importance of DNA bending in nucleosome formation. However, at certain sites the nucleosomal DNAs show dinucleotide enrichments that differ substantially from the cyclization data. These discrepancies can often be correlated with sequence specific contacts that form between histones and DNA.

  11. Selection for increased allocation to offspring number under environmental unpredictability.

    PubMed

    Simons, A M

    2007-03-01

    According to life-history theory, the evolution of offspring size is constrained by the trade-off between allocation of resources to individual offspring and the number of offspring produced. Existing models explore the ecological consequences of offspring size, whereas number is invariably treated simply as an outcome of the trade-off with size. Here I ask whether there is a direct evolutionary advantage of increased allocation to offspring number under environmental unpredictability. Variable environments are expected to select for diversification in the timing of egg hatch and seed germination, yet the dependence of the expression of diversification strategies, and thus parental fitness, on offspring number has not previously been recognized. I begin by showing that well-established sampling theory predicts that a target bethedging diversification strategy is more reliably achieved as offspring number increases. I then use a simulation model to demonstrate that higher offspring number leads to greater geometric mean fitness under environmental uncertainty. Natural selection is thus expected to act directly to increase offspring number under assumptions of environmental unpredictability in season quality.

  12. 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

  13. 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

  14. Aerobic exercise is the critical variable in an enriched environment that increases hippocampal neurogenesis and water maze learning in male C57BL/6J mice

    PubMed Central

    Mustroph, Martina L.; Chen, Shi; Desai, Shalin C.; Cay, Edward B.; DeYoung, Erin K.; Rhodes, Justin S.

    2012-01-01

    Previous studies have shown that housing mice with toys and running wheels increases adult hippocampal neurogenesis and enhances performance on the water maze. However, the relative contribution of running versus enrichment to the neurogenic and pro-cognitive effects is not clear. Recently, it was demonstrated that enrichment devoid of running wheels does not significantly enhance adult hippocampal neurogenesis in female C57BL/6J mice. However, novel toys were not rotated into the cages, and dietary enrichment was not included, so it could be argued that the environment was not enriched enough. In addition, only females were studied, and animals were group-housed, making it impossible to record individual running behavior or to determine the time spent running versus exploring the toys. Therefore, we repeated the study in singly housed male C57BL/6J mice and enhanced enrichment by rotating novel tactile, visual, dietary, auditory, and vestibular stimuli into the cages. Mice were housed for 32 days in one of 4 groups: running-only, enrichment-only, running plus enrichment, and standard cage. The first 10 days BrdU (bromodeoxyuridine) was administered to label dividing cells. The last 5 days mice were tested on the water maze, and then euthanized to measure number of BrdU cells co-labeled with NeuN (neuronal nuclear marker) in the dentate gyrus. Mice in the running-only group ran, on average, greater distances than animals in the running plus enrichment group. The combination of enrichment and running did not significantly increase hippocampal neurogenesis any more than running alone did. Animals in the running-only condition were the only group to show enhanced acquisition on water maze relative to standard cage controls. We confirm and extend the conclusion that environmental enrichment alone does not significantly increase hippocampal neurogenesis or bestow spatial learning benefits in male C57BL/6J mice, even when the modalities of enrichment are very broad. PMID

  15. 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

  16. Comparison of Subtypes of Listeria monocytogenes Isolates from Naturally Contaminated Watershed Samples with and without a Selective Secondary Enrichment

    PubMed Central

    Gorski, Lisa; Walker, Samarpita; Liang, Anita S.; Nguyen, Kimberly M.; Govoni, Jessica; Carychao, Diana; Cooley, Michael B.; Mandrell, Robert E.

    2014-01-01

    Two enrichment methods for Listeria monocytogenes using Immuno Magnetic Separation (IMS) were tested to determine if they selected the same subtypes of isolates. Both methods used a non-selective primary enrichment and one included subculture in Fraser Broth, while the other involved direct plating of IMS beads. Sixty-two naturally contaminated watershed samples from the Central California Coast were used as a source of L. monocytogenes, and subtype diversity was measured by serotype and Multiple Number Variable Tandem Repeat Analysis (MLVA). Three different serotypes were detected from both methods with serotype 4b strains making up 87% of the isolates, serotype 1/2a making up 8%, and serotype 1/2b making up 5%. The data suggest that serotype 1/2a strains were more likely to be isolated from the Fraser Broth culture method. Sixty-two different MLVA types were detected and the more common MLVA types were detected by both culture methods. Forty-three MLVA types were detected only from one culture method or the other, while 19 types were detected from both culture methods. The most common MLVA type-12 was detected in 33 of the 62 water samples, and represented 31% of the isolates from both culture methods. This limited study provides evidence that using both enrichment culture methods allowed for detection of a greater diversity of isolates among the samples than the use of one method alone, and that a wide diversity of L. monocytogenes strains exist in this watershed. PMID:24651315

  17. 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

  18. Selection Based on Indirect Genetic Effects for Growth, Environmental Enrichment and Coping Style Affect the Immune Status of Pigs

    PubMed Central

    Reimert, Inonge; Rodenburg, T. Bas; Ursinus, Winanda W.; Kemp, Bas; Bolhuis, J. Elizabeth

    2014-01-01

    Pigs living in intensive husbandry systems may experience both acute and chronic stress through standard management procedures and limitations in their physical and social environment, which may have implications for their immune status. Here, the effect of a new breeding method where pigs were selected on their heritable influence on their pen mates' growth, and environmental enrichment on the immune status of pigs was investigated. Hereto, 240 pigs with a relatively positive genetic effect on the growth of their pen mates (+SBV) and 240 pigs with a relatively negative genetic effect on the growth of their pen mates (−SBV) were housed in barren or straw-enriched pens from 4 to 23 weeks of age (n  =  80 pens in total). A blood sample was taken from the pigs before, three days after a 24 h regrouping test, and at week 22. In addition, effects of coping style, as assessed in a backtest, and gender were also investigated. Mainly, +SBV were found to have lower leukocyte, lymphocyte and haptoglobin concentrations than -SBV pigs. Enriched housed pigs had a lower neutrophil to lymphocyte (N:L) ratio and lower haptoglobin concentrations, but had higher antibody titers specific for Keyhole Limpet Hemocyanin (KLH) than barren housed pigs. No interactions were found between SBV class and housing. Furthermore, pigs with a proactive coping style had higher alternative complement activity and, in the enriched pens, higher antibody titers specific for KLH than pigs with a reactive coping style. Lastly, females tended to have lower leukocyte, but higher haptoglobin concentrations than castrated males. Overall, these results suggest that +SBV pigs and enriched housed pigs were less affected by stress than -SBV and barren housed pigs, respectively. Moreover, immune activation might be differently organized in individuals with different coping styles and to a lesser extent in individuals of opposite genders. PMID:25275507

  19. 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

  20. Facile preparation of core-shell magnetic metal-organic framework nanospheres for the selective enrichment of endogenous peptides.

    PubMed

    Xiong, Zhichao; Ji, Yongsheng; Fang, Chunli; Zhang, Quanqing; Zhang, Lingyi; Ye, Mingliang; Zhang, Weibing; Zou, Hanfa

    2014-06-10

    Facile preparation of core-shell magnetic metal-organic framework nanospheres by a layer-by-layer approach is presented. The nanospheres have high surface area (285.89 cm(2)  g(-1)), large pore volume (0.18 cm(3)  g(-1)), two kinds of mesopores (2.50 and 4.72 nm), excellent magnetic responsivity (55.65 emu g(-1)), structural stability, and good dispersibility. The combination of porosity, hydrophobicity, and uniform magnetism was exploited for effective enrichment of peptides with simultaneous exclusion of high molecular weight proteins. The nanospheres were successfully applied in the selective enrichment of endogenous peptides in human serum.

  1. 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

  2. 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.

  3. Walnut-enriched diet increases the association of LDL from hypercholesterolemic men with human HepG2 cells.

    PubMed

    Muñoz, S; Merlos, M; Zambón, D; Rodríguez, C; Sabaté, J; Ros, E; Laguna, J C

    2001-12-01

    In a randomized, cross-over feeding trial involving 10 men with polygenic hypercholesterolemia, a control, Mediterranean-type cholesterol-lowering diet, and a diet of similar composition in which walnuts replaced approximately 35% of energy from unsaturated fat, were given for 6 weeks each. Compared with the control diet, the walnut diet reduced serum total and LDL cholesterol by 4.2% (P = 0.176), and 6.0% (P = 0.087), respectively. No changes were observed in HDL cholesterol, triglycerides, and apolipoprotein A-I levels or in the relative proportion of protein, triglycerides, phospholipids, and cholesteryl esters in LDL particles. The apolipoprotein B level declined in parallel with LDL cholesterol (6.0% reduction). Whole LDL, particularly the triglyceride fraction, was enriched in polyunsaturated fatty acids from walnuts (linoleic and alpha-linolenic acids). In comparison with LDL obtained during the control diet, LDL obtained during the walnut diet showed a 50% increase in association rates to the LDL receptor in human hepatoma HepG2 cells. LDL uptake by HepG2 cells was correlated with alpha-linolenic acid content of the triglyceride plus cholesteryl ester fractions of LDL particles (r(2) = 0.42, P < 0.05). Changes in the quantity and quality of LDL lipid fatty acids after a walnut-enriched diet facilitate receptor-mediated LDL clearance and may contribute to the cholesterol-lowering effect of walnut consumption.

  4. Increasing intracellular bioavailable copper selectively targets prostate cancer cells.

    PubMed

    Cater, Michael A; Pearson, Helen B; Wolyniec, Kamil; Klaver, Paul; Bilandzic, Maree; Paterson, Brett M; Bush, Ashley I; Humbert, Patrick O; La Fontaine, Sharon; Donnelly, Paul S; Haupt, Ygal

    2013-07-19

    The therapeutic efficacy of two bis(thiosemicarbazonato) copper complexes, glyoxalbis[N4-methylthiosemicarbazonato]Cu(II) [Cu(II)(gtsm)] and diacetylbis[N4-methylthiosemicarbazonato]Cu(II) [Cu(II)(atsm)], for the treatment of prostate cancer was assessed in cell culture and animal models. Distinctively, copper dissociates intracellularly from Cu(II)(gtsm) but is retained by Cu(II)(atsm). We further demonstrated that intracellular H2gtsm [reduced Cu(II)(gtsm)] continues to redistribute copper into a bioavailable (exchangeable) pool. Both Cu(II)(gtsm) and Cu(II)(atsm) selectively kill transformed (hyperplastic and carcinoma) prostate cell lines but, importantly, do not affect the viability of primary prostate epithelial cells. Increasing extracellular copper concentrations enhanced the therapeutic capacity of both Cu(II)(gtsm) and Cu(II)(atsm), and their ligands (H2gtsm and H2atsm) were toxic only toward cancerous prostate cells when combined with copper. Treatment of the Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) model with Cu(II)(gtsm) (2.5 mg/kg) significantly reduced prostate cancer burden (∼70%) and severity (grade), while treatment with Cu(II)(atsm) (30 mg/kg) was ineffective at the given dose. However, Cu(II)(gtsm) caused mild kidney toxicity in the mice, associated primarily with interstitial nephritis and luminal distention. Mechanistically, we demonstrated that Cu(II)(gtsm) inhibits proteasomal chymotrypsin-like activity, a feature further established as being common to copper-ionophores that increase intracellular bioavailable copper. We have demonstrated that increasing intracellular bioavailable copper can selectively kill cancerous prostate cells in vitro and in vivo and have revealed the potential for bis(thiosemicarbazone) copper complexes to be developed as therapeutics for prostate cancer.

  5. Cocaine selectively increases striatonigral dynorphin levels by a dopaminergic mechanism.

    PubMed

    Sivam, S P

    1989-09-01

    The influence of the acute (single dose) or subchronic (one dose daily for 4 days) administration of cocaine to Sprague-Dawley rats on striatal enkephalin (Met5-enkephalin) and striatonigral tachykinin (substance P) and dynorphin [dynorphin A (1-8), DYN] levels was investigated. The peptide levels were determined by radioimmunoassay. The concentrations of the striatal levels of dopamine (DA), 5-hydroxytryptamine and their acid metabolites were determined by high-performance liquid chromatography with electrochemical detection. An acute administration of cocaine (20 or 30 mg/kg i.p.) did not affect the peptide levels in the striatum or in the substantia nigra. A regimen of subchronic administration of cocaine (20 mg/kg/day for 4 days) increased the striatonigral DYN levels, without altering the levels of Met5-enkephalin or substance P. The increase in DYN levels were persistent for at least 4 days after the last dose of the subchronic administration of cocaine. The DYN levels returned to control values by 12 days after the last dose. The DA levels in the striatum were increased 30 min after a single dose of cocaine. None of the other treatments elicited any changes in DA or 5-hydroxytryptamine or their metabolites. The subchronic cocaine administration to dopaminergic denervated rats with 6-hydroxydopamine failed to evoke any increase in DYN levels in the striatum or substantia nigra. The concurrent administration of the D1 DA antagonist, SCH-23390, or the D2 DA antagonist, spiperone, to the subchronic regimen of cocaine also blocked the cocaine-induced increase in DYN levels. These results indicate that cocaine selectively enhances the synthesis or decreases the release of DYN in the striatonigral neurons.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Increasing the hydrogenation activity of commercial catalysts for selective hydrocracking

    SciTech Connect

    Khashagul`gova, N.S.; Freiman, L.L.; Zelentsov, Yu.N.

    1994-07-01

    The catalysts generally used in hydrodewaxing or selective hydrocracking of n-paraffins are zeolites with the pentasil structure: TsVK, TsVM, TsVN, and Ultrasil. For use in the production of high-quality transformer oils from paraffinic feedstocks, these catalysts have not only a high cracking activity but also an adequate hydrogenating activity. Catalysts containing a nickel-molybdenum complex (or nickel molybdate synthesized by a specific method) are higher in hydrogenating activity in comparison with catalysts in which the metals are introduced by coextrusion or impregnation. Precipitation of a nickel-molybdenum complex on a solid support (aluminosilicate or zeolite) tends to increase its hydrogenating activity, so that the content of the hydrogenating metals in the catalyst can be reduced. This report describes studies on catalysts based on TsVM and TsVN high-silica zeolites.

  7. Selective extraction and enrichment of glycoproteins based on boronate affinity SPME and determination by CIEF-WCID.

    PubMed

    Li, Lixian; Xia, Zhining; Pawliszyn, Janusz

    2015-07-30

    In this study, a new thin-film boronic acid coating was developed for solid-phase microextraction (SPME) followed by capillary isoelectric focusing with whole-column imaging detection (CIEF-WCID). Boronate functionalized particles of phenylboronic acid (PBA) and 3-aminophenylboronic acid (3-aPBA) were utilized as boronate affinity solid phase coating on thin-film stainless steel blades for selective extraction and enrichment of glycoproteins. The process of extraction and elution could be easily controlled by adjusting pH. To test specificity, asialofetuin and lactoferrin were selected as glycoproteins test molecules, while BSA and myoglobin were used as control non-glycoproteins in this study. The boronate affinity coating was characterized. The effect of buffer, pH, extraction profiles and elution profiles were investigated. The developed method was successfully applied to extract glycoproteins from standard buffer, PBS, human plasma and 10-fold diluted human blood using two kinds of boronate affinity blades. Boronate affinity SPME could be a promising tool for selective extraction and enrichment of low-abundance glycoproteins in real biological samples.

  8. 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

  9. 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

  10. 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

  11. Estrogen withdrawal selectively increases serotonin reactivity in rabbit basilar artery.

    PubMed

    Shay, J; Futo, J; Badrov, N; Moss, J

    1994-01-01

    Clinical observations and laboratory investigations suggest that gender and menstrual status modulate cerebrovascular reactivity. We prepared 7 groups of rabbits (I) males (II) oophorectomized untreated females, (III) testosterone treated oophorectomized females, (IV) superovulated females, (V) superovulated estrogen withdrawn females, (VI) estrogen treated oophorectomized females, and (VII) estrogen withdrawn females to mimic phases of the estrous cycle and compare cerebral basilar artery reactivity to serotonin (5-HT) and norepinephrine (NE) in vitro. Basilar artery sensitivity to 5-HT vasoconstriction was increased in oophorectomized, acutely estrogen withdrawn females (Group VII) when compared to estrogen maintained and the other groups (p < 0.0001). There was a significant reduction in 5-HT sensitivity in superovulated females (Group IV) (p < 0.001). The change in 5-HT sensitivity is selective and was not observed for NE. Nitroarginine treatment and mechanical denudement resulted in higher Tmax and lower ED50 for both NE and 5-HT regardless of hormonal manipulation. We conclude that estrogen withdrawal increases 5-HT vasoreactivity by an endothelium independent mechanism. PMID:8084212

  12. Increasing selection response by Bayesian modeling of heterogeneous environmental variances

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heterogeneity of environmental variance among genotypes reduces selection response because genotypes with higher variance are more likely to be selected than low-variance genotypes. Modeling heterogeneous variances to obtain weighted means corrected for heterogeneous variances is difficult in likel...

  13. Selection of potential IAEA inspection strategies involving cascade access at the Portsmouth Gas Centrifuge Enrichment Plant (GCEP)

    SciTech Connect

    Not Available

    1981-04-13

    This report has been prepared as a US contribution to Team 4 of the Hexapartite Safeguards Project. It provides to the Team 4 participants one example of an approach, which has been used in the United States, to developing a range of safeguards strategies involving differing degrees of access to cascade areas of centrifuge enrichment plants. Its purpose is to facilitate the work of other Hexapartite participants in completing Task II of Team 4's terms of reference. The scope of this report is limited to identifying safeguards approaches for the Portsmouth Gas Centrifuge Enrichment Plant (GCEP) which involve differing degrees of access to the cascade area. This report provides a method for selecting cascade access inspection strategies at GCEP which appear promising for more detailed evaluation. It is quite important to note, however, that the effectiveness and practicability of these strategies have not been established at the present. In addition, some strategies have been included on the basis of very preliminary calculations and considerations which have not been validated. Thus, some of these strategies may ultimately be rejected because they prove to be impracticable. Considerations of cost and the possible transfer of information and technology related to the production of enriched uranium will also be pertinent in considering the degrees and frequency of access to the cascade areas of centrifuge enrichment plants. This report describes the process for combining technical measures, implementation approaches and objectives to arrive at the total number of theoretically possible combinations. It then describes how these combinations may be reduced in a series of steps to a number that is more manageable for detailed evaluation. The process is shown schematically.

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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.

  20. Environmental enrichment improves age-related immune system impairment: long-term exposure since adulthood increases life span in mice.

    PubMed

    Arranz, Lorena; De Castro, Nuria M; Baeza, Isabel; Maté, Ianire; Viveros, Maria Paz; De la Fuente, Mónica

    2010-08-01

    Age-related changes in immunity have been shown to highly influence morbidity and mortality. The aim of the present work was to study the effects of environmental enrichment (EE) (8-16 weeks) on several functions and oxidative stress parameters of peritoneal leukocytes, previously described as health and longevity markers, in mice at different ages, namely adult (44 +/- 4 weeks), old (69 +/- 4 weeks), and very old (92 +/- 4 weeks). Mortality rates were monitored in control and enriched animals, and effects on survival of long-term exposure to EE until natural death were determined. The results showed that exposure to EE was efficient in improving the function (i.e., macrophage chemotaxis and phagocytosis, lymphocyte chemotaxis and proliferation, natural killer cell activity, interleukin-2 and tumor necrosis factor-alpha levels) and decreasing the oxidative-inflammatory stress (i.e., lowered oxidized glutathione content, xanthine oxidase activity, expression of Toll-like receptors 2 and 4 on CD4 and CD8 cells, and increased reduced glutathione and glutathione peroxidase and catalase activities) of immune cells. These positive effects of EE were especially remarkable in animals at older ages. Importantly, long-term exposure to EE from adult age and until natural death stands out as a useful strategy to extend longevity. Thus, the present work confirms the importance of maintaining active mental and/or physical activity aiming to improve quality of life in terms of immunity, and demonstrates that this active life must be initiated at early stages of the aging process and preserved until death to improve life span.

  1. Environmental enrichment preceding early adulthood methylphenidate treatment leads to long term increase of corticosterone and testosterone in the rat.

    PubMed

    Avital, Avi; Dolev, Talya; Aga-Mizrachi, Shlomit; Zubedat, Salman

    2011-01-01

    Attention-deficit/hyperactivity disorder (ADD/ADHD) has been emerging as a world-wide psychiatric disorder. There appears to be an increasing rate of stimulant drug abuse, specifically methylphenidate (MPH) which is the most common treatment for ADHD, among individuals who do not meet the criteria for ADHD and particularly for cognitive enhancement among university students. However, the long term effects of exposure to MPH are unknown. Thus, in light of a developmental approach in humans, we aimed to test the effects of adolescence exposure to enriched environment (EE) followed by MPH administration during early adulthood, on reactions to stress in adulthood. Specifically, at approximate adolescence [post natal days (PND) 30-60] rats were reared in EE and were treated with MPH during early adulthood (PND 60-90). Adult (PND 90-92) rats were exposed to mild stress and starting at PND 110, the behavioral and endocrine effects of the combined drug and environmental conditions were assessed. Following adolescence EE, long term exposure to MPH led to decreased locomotor activity and increased sucrose preference. EE had a beneficial effect on PPI (attentive abilities), which was impaired by long term exposure to MPH. Finally, the interaction between EE and, exposure to MPH led to long-term elevated corticosterone and testosterone levels. In view of the marked increase in MPH consumption over the past decade, vigilance is crucial in order to prevent potential drug abuse and its long term detrimental consequences.

  2. 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

  3. 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

  4. 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…

  5. A selective broth enrichment combined with real-time nuc-mecA-PCR in the exclusion of MRSA.

    PubMed

    Pasanen, Tanja; Korkeila, Maija; Mero, Sointu; Tarkka, Eveliina; Piiparinen, Heli; Vuopio-Varkila, Jaana; Vaara, Martti; Tissari, Päivi

    2010-01-01

    We analyzed the performance of a selective enrichment broth combined with Taqman-based real-time duplex nuc-mecA-PCR to expedite the screening of methicillin-resistant Staphylococcus aureus (MRSA). We found the broth to be able to select MRSA strains (oxacillin MIC range 4-256 microg/ml) from MSSA strains. A total of 31 MRSA strains were found from 1250 clinical samples screened. The nuc-mecA-PCR was positive from all enrichment broths containing MRSA. From the remaining 1219 samples negative for MRSA on culture/subculture, 138 samples were nuc+/mecA+ in PCR. The sensitivity of the test was 93.5%, specificity 88.6%, positive predictive value 17.3%, and negative predictive value 99.8% as compared to culture. Thus, with this method, the negative MRSA results can be reliably reported within 24-48 h from sampling. The method is a practical additional alternative to those already described for the same purpose.

  6. 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

  7. 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

  8. Control of selectivity via nanochemistry: monolithic capillary column containing hydroxyapatite nanoparticles for separation of proteins and enrichment of phosphopeptides.

    PubMed

    Krenkova, Jana; Lacher, Nathan A; Svec, Frantisek

    2010-10-01

    New monolithic capillary columns with embedded commercial hydroxyapatite nanoparticles have been developed and used for protein separation and selective enrichment of phosphopeptides. The rod-shaped hydroxyapatite nanoparticles were incorporated into the poly(2-hydroxyethyl methacrylate-co-ethylene dimethacrylate) monolith by simply admixing them in the polymerization mixture followed by in situ polymerization. The effect of percentages of monomers and hydroxyapatite nanoparticles in the polymerization mixture on the performance of the monolithic column was explored in detail. We found that the loading capacity of the monolith is on par with other hydroxyapatite separation media. However, the speed at which these columns can be used is higher due to the fast mass transport. The function of the monolithic columns was demonstrated with the separations of a model mixture of proteins including ovalbumin, myoglobin, lysozyme, and cytochrome c as well as a monoclonal antibody and its aggregates with protein A. Selective enrichment and MALDI/MS characterization of phosphopeptides fished-out from complex peptide mixtures of ovalbumin, α-casein, and β-casein digests were also achieved using the hydroxyapatite monolith.

  9. Selenium enrichment of broccoli sprout extract increases chemosensitivity and apoptosis of LNCaP prostate cancer cells

    PubMed Central

    2009-01-01

    Background Broccoli is a Brassica vegetable that is believed to possess chemopreventive properties. Selenium also shows promise as an anticancer agent. Thus, selenium enrichment of broccoli has the potential to enhance the anticancer properties of broccoli sprouts. Method Selenium-enriched broccoli sprouts were prepared using a sodium selenite solution. Their anticancer properties were evaluated in human prostate cancer cell lines and compared with those of a control broccoli sprout extract. Results Selenium-enriched broccoli sprouts were superior to normal broccoli sprouts in inhibiting cell proliferation, decreasing prostate-specific antigen secretion, and inducing apoptosis of prostate cancer cells. Furthermore, selenium-enriched broccoli sprouts but, not normal broccoli sprouts, induced a downregulation of the survival Akt/mTOR pathway. Conclusion Our results suggest that selenium-enriched broccoli sprouts could potentially be used as an alternative selenium source for prostate cancer prevention and therapy. PMID:19943972

  10. 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…

  11. 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...

  12. 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.

  13. 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

  14. 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.

  15. Bread enriched with microencapsulated tuna oil increases plasma docosahexaenoic acid and total omega-3 fatty acids in humans.

    PubMed

    Yep, Yolande L; Li, Duo; Mann, Neil J; Bode, Ortwin; Sinclair, Andrew J

    2002-01-01

    The aim of this study was to determine the acute and chronic effects of low doses of long chain (LC) n-3 polyunsaturated fatty acids (PUFA) (<100 mg per day) on plasma LC n-3 PUFA levels using a novel delivery form; bread containing microencapsulated tuna oil (MTO). Six omnivores (three men and three women) participated in the acute study, which involved ingesting a prototype MTO bread containing approximately 80 mg of LC n-3 PUFA/four slices. Plasma triacylglycerol fatty acid compositions were measured after an overnight fast and postprandially at 2 and 4 h. In the chronic study, 10 vegetarian subjects (nine men and one woman) consumed MTO bread at six to eight slices/day (comprising 60 mg of LC n-3 PUFA) as the only dietary source of these PUFA for three weeks. Fasting plasma total and phospholipid fatty acid compositions were measured at baseline and endpoint. In the acute study, the proportions of 22:6 n-3 and total n-3 PUFA in plasma triacylglycerol were significantly increased (P < 0.05). In the chronic study, the proportions of 20:5 n-3, 22:5 n-3, 22:6 n-3, total n-3 PUFA in plasma, and 22:6 n-3 and total n-3 PUFA in plasma phospholipid fractions were significantly increased (P < 0.05) at the endpoint compared with the baseline. This study showed that a low dose of LC n-3 PUFA, consumed as MTO-enriched bread, was bioavailable, as measured by an increase in LC n-3 PUFA levels in the plasma of human subjects.

  16. 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

  17. 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

  18. Hyperoxaluria leads to dysbiosis and drives selective enrichment of oxalate metabolizing bacterial species in recurrent kidney stone endures

    PubMed Central

    Suryavanshi, Mangesh V.; Bhute, Shrikant S.; Jadhav, Swapnil D.; Bhatia, Manish S.; Gune, Rahul P.; Shouche, Yogesh S.

    2016-01-01

    Hyperoxaluria due to endogenously synthesized and exogenously ingested oxalates is a leading cause of recurrent oxalate stone formations. Even though, humans largely rely on gut microbiota for oxalate homeostasis, hyperoxaluria associated gut microbiota features remain largely unknown. Based on 16S rRNA gene amplicons, targeted metagenomic sequencing of formyl-CoA transferase (frc) gene and qPCR assay, we demonstrate a selective enrichment of Oxalate Metabolizing Bacterial Species (OMBS) in hyperoxaluria condition. Interestingly, higher than usual concentration of oxalate was found inhibitory to many gut microbes, including Oxalobacter formigenes, a well-characterized OMBS. In addition a concomitant enrichment of acid tolerant pathobionts in recurrent stone sufferers is observed. Further, specific enzymes participating in oxalate metabolism are found augmented in stone endures. Additionally, hyperoxaluria driven dysbiosis was found to be associated with oxalate content, stone episodes and colonization pattern of Oxalobacter formigenes. Thus, we rationalize the first in-depth surveillance of OMBS in the human gut and their association with hyperoxaluria. Our findings can be utilized in the treatment of hyperoxaluria associated recurrent stone episodes. PMID:27708409

  19. 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

  20. 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

  1. 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

  2. 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

  3. Substrate-Based Fragment Identification for the Development of Selective, Nonpeptidic Inhibitors of Striatal-Enriched Protein Tyrosine Phosphatase

    PubMed Central

    Baguley, Tyler D.; Xu, Hai-Chao; Chatterjee, Manavi; Nairn, Angus C.; Lombroso, Paul J.; Ellman, Jonathan A.

    2013-01-01

    High levels of striatal-enriched protein tyrosine phosphatase (STEP) activity are observed in a number of neuropsychiatric disorders such as Alzheimer’s disease. Over-expression of STEP results in the dephosphorylation and inactivation of many key neuronal signaling molecules, including ionotropic glutamate receptors. Moreover, genetically reducing STEP levels in AD mouse models significantly reversed cognitive deficits and decreased glutamate receptor internalization. These results support STEP as a potential target for drug discovery for the treatment of Alzheimer’s disease. Herein, a substrate-based approach for the discovery and optimization of fragments called substrate activity screening (SAS) has been applied to the development of low molecular weight (<450 Da) and non-peptidic, single-digit micromolar mechanism-based STEP inhibitors with greater than 20-fold selectivity across multiple tyrosine and dual specificity phosphatases. Significant levels of STEP inhibition in rat cortical neurons are also observed. PMID:24083656

  4. Both increases in immature dentate neuron number and decreases of immobility time in the forced swim test occurred in parallel after environmental enrichment of mice.

    PubMed

    Llorens-Martín, M V; Rueda, N; Martínez-Cué, C; Torres-Alemán, I; Flórez, J; Trejo, J L

    2007-07-13

    A direct relation between the rate of adult hippocampal neurogenesis in mice and the immobility time in a forced swim test after living in an enriched environment has been suggested previously. In the present work, young adult mice living in an enriched environment for 2 months developed considerably more immature differentiating neurons (doublecortin-positive, DCX(+)) than control, non-enriched animals. Furthermore, we found that the more DCX(+) cells they possessed, the lower the immobility time they scored in the forced swim test. This DCX(+) subpopulation is composed of mostly differentiating dentate neurons independently of the birthdates of every individual cell. However, variations found in this subpopulation were not the result of a general effect on the survival of any newborn neuron in the granule cell layer, as 5-bromo-2-deoxyuridine (BrdU)-labeled cells born during a narrow time window included in the longer lifetime period of DCX(+) cells, were not significantly modified after enrichment. In contrast, the survival of the mature population of neurons in the granule cell layer of the dentate gyrus in enriched animals increased, although this did not influence their performance in the Porsolt test, nor did it influence the dentate gyrus volume or granule neuronal nuclei size. These results indicate that the population of immature, differentiating neurons in the adult hippocampus is one factor directly related to the protective effect of an enriched environment against a highly stressful event.

  5. Intracellular Triggering of Fas Aggregation and Recruitment of Apoptotic Molecules into Fas-enriched Rafts in Selective Tumor Cell Apoptosis

    PubMed Central

    Gajate, Consuelo; del Canto-Jañez, Esther; Acuña, A. Ulises; Amat-Guerri, Francisco; Geijo, Emilio; Santos-Beneit, Antonio M.; Veldman, Robert J.; Mollinedo, Faustino

    2004-01-01

    We have discovered a new and specific cell-killing mechanism mediated by the selective uptake of the antitumor drug 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH3, Edelfosine) into lipid rafts of tumor cells, followed by its coaggregation with Fas death receptor (also known as APO-1 or CD95) and recruitment of apoptotic molecules into Fas-enriched rafts. Drug sensitivity was dependent on drug uptake and Fas expression, regardless of the presence of other major death receptors, such as tumor necrosis factor (TNF) receptor 1 or TNF-related apoptosis-inducing ligand R2/DR5 in the target cell. Drug microinjection experiments in Fas-deficient and Fas-transfected cells unable to incorporate exogenous ET-18-OCH3 demonstrated that Fas was intracellularly activated. Partial deletion of the Fas intracellular domain prevented apoptosis. Unlike normal lymphocytes, leukemic T cells incorporated ET-18-OCH3 into rafts coaggregating with Fas and underwent apoptosis. Fas-associated death domain protein, procaspase-8, procaspase-10, c-Jun amino-terminal kinase, and Bid were recruited into rafts, linking Fas and mitochondrial signaling routes. Clustering of rafts was necessary but not sufficient for ET-18-OCH3–mediated cell death, with Fas being required as the apoptosis trigger. ET-18-OCH3–mediated apoptosis did not require sphingomyelinase activation. Normal cells, including human and rat hepatocytes, did not incorporate ET-18-OCH3 and were spared. This mechanism represents the first selective activation of Fas in tumor cells. Our data set a framework for the development of more targeted therapies leading to intracellular Fas activation and recruitment of downstream signaling molecules into Fas-enriched rafts. PMID:15289504

  6. Neonatal handling and environmental enrichment increase the expression of GAP-43 in the hippocampus and promote cognitive abilities in prenatally stressed rat offspring.

    PubMed

    Zhang, Zhengyu; Zhang, Hua; Du, Baoling; Chen, Zhiqiang

    2012-07-26

    Neonatal handling and environmental enrichment have been used to aid the treatment and recovery of a diverse variety of brain dysfunctions. However, the underlying mechanism and the effects on cognitive function following neonatal handling and environmental enrichment are still unclear. In this study, we investigated GAP-43 protein levels in the hippocampus of prenatally stressed rat pups by Western blot on postnatal day (P) 10, P20 and P45. The cognitive ability of prenatally stressed rat pups was tested by using the Morris water maze on P45. GAP-43 protein levels were upregulated on P10 in the prenatal restraint stress (RS) group and the prenatal restraint stress plus neonatal handling and environmental enrichment (RE) group compared to the negative control (NC) group. However, the expression of GAP-43 in RS pups was lower on P20 and P45 than that in NC and RE pups. Exposure to prenatal stress prolonged average latency and total swim distance, but neonatal handling and environmental enrichment could reverse the change. Differences were also observed in the selection of search strategies. These results indicate that neonatal handling and environmental enrichment can improve the spatial learning and memory ability of prenatally stressed offspring, and the possible mechanism is the upregulation of GAP-43.

  7. 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...

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. Ultrathin-yttrium phosphate-shelled polyacrylate-ferriferrous oxide magnetic microspheres for rapid and selective enrichment of phosphopeptides.

    PubMed

    Sun, Ye; Wang, He-Fang

    2013-11-01

    Rapid and selective enrichment of phosphopeptides from complex biological samples is essential and challenging in phosphorylated proteomics. We present the direct growth of the ultrathin YPO4 shell on the surface of polyacrylate capped secondary Fe3O4 microspheres (PA-Fe3O4@YPO4) for the rapid and selective trapping phosphopeptides from complex samples. The prepared PA-Fe3O4@YPO4 could be rapidly harvested in the presence of an applied magnetic field and easily re-dispersed in solutions after removing the external magnet. The ultrathin YPO4 shell on super-hydrophilic PA-Fe3O4 has the advantages of fast adsorption/desorption dynamics and low non-specific adsorption, thus trapping of phosphopeptides from the tryptic digests mixture of β-casein/BSA with molar ratio of 1/300 is achieved in 20s adsorption/desorption time. Two phosphopeptides can still be detected with a signal to noise ratio (S/N) over 3 when the amount of β-casein was as low as 8 fmol.

  13. 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

  14. 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.

  15. A hybrid fever therapy for increased tumor selectivity.

    PubMed

    Noe, Garry

    2016-04-01

    Lipopolysaccharide (LPS), mediator of the Coley and Shwartzman fever therapies, is a potent endotoxin capable of inducing sepsis at moderate intravenous doses, which currently limits its experimental and clinical use. By exploiting elevated G-CSF concentrations and neutrophil numbers within tumors, it may be possible to selectively trigger a sepsis-like syndrome in malignant tissues using only moderate hyperthermia and low-dose LPS, leaving normal organs unaffected. Analogous to the organ failure that can result from severe sepsis, repeated application of the proposed procedure could lead to tumor necrosis and regression. Biomarkers including heat shock proteins and circulating endothelial cells, and intravital microscopy of intravascular NETs, microthrombi, and bleeding in tumors can be used to test predicted consequences of this therapy. The two components of this hybrid approach, hyperthermia and acute but mild endotoxemia, could provide a tumor-specific therapeutic modality with relatively mild side effects, and therefore permit repeated application over an extended treatment period. PMID:26968911

  16. 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

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

    PubMed

    Kolyadko, Vladimir N; Lushchekina, Sofya V; 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

  18. Enriched cereal bars are more effective in increasing plasma quercetin compared with quercetin from powder-filled hard capsules.

    PubMed

    Egert, Sarah; Wolffram, Siegfried; Schulze, Beate; Langguth, Peter; Hubbermann, Eva Maria; Schwarz, Karin; Adolphi, Berit; Bosy-Westphal, Anja; Rimbach, Gerald; Müller, Manfred James

    2012-02-01

    The flavonol quercetin, is one of the major flavonoids found in edible plants. The bioavailability of quercetin in humans may be influenced by the food matrix in which it is consumed as well as by its chemical and physical form. The objective of the present study was to investigate the biokinetics of quercetin from quercetin-enriched cereal bars and quercetin powder-filled hard capsules. In a randomised, single-blinded, diet-controlled cross-over study, six healthy women aged 22-28 years took a single oral dose of approximately 130 mg quercetin equivalents from either quercetin-enriched cereal bars (containing 93·3 % quercetin aglycone plus 6·7 % quercetin-4'-glucoside) or quercetin powder-filled hard capsules (100 % quercetin aglycone). Blood samples were drawn before and after quercetin administration over a 24 h period. The concentrations of quercetin and its monomethylated derivatives, isorhamnetin (3'-O-methyl quercetin) and tamarixetin (4'-O-methyl quercetin), were measured by HPLC with fluorescence detection after plasma enzymatic treatment. The systemic availability as determined by comparing the plasma concentration-time curves of quercetin was found to be five times and the cmax values six times higher after ingestion of 130 mg quercetin by quercetin-enriched cereal bars than after ingestion by quercetin capsules. In contrast, tmax did not differ significantly between the two treatments. The cmax values for isorhamnetin and tamarixetin were four and nine times higher after ingestion of quercetin by quercetin-enriched cereal bars than after ingestion by quercetin capsules. In conclusion, quercetin from quercetin-enriched cereal bars is significantly more bioavailable than from quercetin powder-filled hard capsules. PMID:21774840

  19. Increasing the energy yield of mechanochemical transformations: selected case studies.

    PubMed

    Politov, Anatoly; Golyazimova, Olga

    2014-01-01

    The products of mechanical treatment are surface atoms or molecules, substances with a crystal structure different from their initial one (another polymorph, amorphous), point or linear defects, radicals and new chemical substances. It is often assumed, that to increase the yield of the products of a mechanical treatment, it is necessary to increase the treatment time and the mechanical power input. In view of the low energy yield of many mechanochemical transformations, this leads to high power consumption and contamination of the matter under treatment with the wear products of the material of a mill or reactor, in which the mechanical treatment is carried out. As a result, the technological attractiveness of mechanochemical processes is reduced, so that many mechanochemical transformations that have been discovered recently do not reach the stage of commercialization. In the present paper we describe different examples of increasing successfully the energy yield of mechanochemical processes, by a factor of several times to several orders of magnitude, for inorganic and organic substances. An increase in the energy yield of mechanochemical transformations opens new possibilities for their practical usage. In particular, the methods of preliminary treatment and the modes of conducting enzymatic processes that may find application in the production of second-generation biofuels are discussed using lignocellulose materials as examples.

  20. Growth differences and competition between Listeria monocytogenes strains determine their predominance on ham slices and lead to bias during selective enrichment with the ISO protocol.

    PubMed

    Zilelidou, Evangelia; Manthou, Evanthia; Skandamis, Panagiotis

    2016-10-17

    Listeria monocytogenes strains are widespread in the environment where they live well mixed, often resulting in multiple strains contaminating a single food sample. The occurrence of different strains in the same food might trigger strain competition, contributing to uneven growth of strains in food and to bias during selective procedures. We tested the growth of seven L. monocytogenes strains (C5, 6179, ScottA, PL24, PL25, PL26, PL27) on ham slices and on nutrient-rich agar at 10°C, singly and in combinations. Strains were made resistant to different antibiotics for their selective enumeration. In addition, growth of single strains (axenic culture) and competition between strains in xenic cultures of two strains was evaluated in enrichment broth and on selective agar. According to ISO 11290-1:1996/Amd 1:2004 standard protocol for detection of L. monocytogenes, two enrichment steps both followed by streaking on ALOA were performed. Strain cultures were directly added in the enrichment broth or used to inoculate minced beef and sliced hams which were then mixed with enrichment broth. 180-360 colonies were used to determine the relative percentage of each strain recovered on plates per enrichment step. The data showed a significant impact of co-cultivation on the growth of six out of seven strains on ham and a bias towards certain strains during selective enrichment. Competition was manifested by: (i) cessation of growth for the outcompeted strain when the dominant strain reached stationary phase, (ii) reduction of growth rates or (iii) total suppression of growth (both on ham and in enrichment broth or ALOA). Outgrowth of strains by their competitors on ALOA resulted in limited to no recovery, with the outcompeting strain accounting for up to 100% of the total recovered colonies. The observed bias was associated with the enrichment conditions (i.e. food type added to the enrichment broth) and the strain-combination. The outcome of growth competition on food or

  1. Amine Chemistry Method for Selective Enrichment of N-Linked Glycopeptides for Glycoproteomics Analysis.

    PubMed

    Zhang, Zhang; Sun, Deguang; Cong, Yuting; Mao, Jiawei; Huang, Junfeng; Qin, Hongqiang; Liu, Jing; Huang, Guang; Wang, Liming; Ye, Mingliang; Zou, Hanfa

    2015-09-01

    An amine chemistry method was developed for the extraction of N-glycopeptides using amine-functionalized beads for glycoproteomics analysis. Two reductive amination reactions between primary amine and aldehyde were employed in this approach. The first one was to block the primary amines in the peptides by addition of formaldehyde and sodium cyanoborohydride into the peptide sample, and the second one was to couple the glycopeptides onto solid phase beads by incubating the glycopeptides containing aldehyde groups (oxidized by periodate) with the amine-functionalized beads in the presence of sodium cyanoborohydride. It was demonstrated that the blocking of primary amines in the peptides by the first reductive amination reaction prior to the periodate oxidation made the amine chemistry method very efficient and sensitive. This new method was validated by analysis of glycoprotein standards as well as proteome samples. It was found that this new method led to significant increase in the identification of N-glycosites compared with the conventional hydrazide chemistry method.

  2. Digoxin is a selective modifier increasing platinum drug anticancer activity.

    PubMed

    Bogush, T A; Chernov, V Yu; Dudko, E A; Shprakh, Z S; Bogush, E A; Polotsky, B E; Tjulandin, S A; Davydov, M I

    2016-05-01

    Using the model of breast cancer Ehrlich ascites tumor in mice, we showed that a sigle intraperitoneal injection of cardiac glycoside digoxin 1 h before the intraperitoneal injection of cisplatin increased the anticancer effect of the cytostatic drug more than twice when recalculated for the dose. It is assumed that the modifying effect of digoxin is determined by the direct inhibition of glycolysis in tumor cells. Taking into account the design of the study, we consider promising the clinical evaluation of the effectiveness of digoxin as a modifier of cisplatin efficiency in intracavitary therapy of ascites cancers with pleural and abdominal dissenmination. PMID:27417726

  3. 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.

  4. 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

  5. Use of manufactured foods enriched with fish oils as a means of increasing long-chain n-3 polyunsaturated fatty acid intake.

    PubMed

    Lovegrove, J A; Brooks, C N; Murphy, M C; Gould, B J; Williams, C M

    1997-08-01

    The objectives of the present study were to determine the feasibility of using manufactured foods, enriched with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) as a means of increasing the intake of these n-3 polyunsaturated fatty acids (PUFA), and to determine the effect of the consumption of these foods on postprandial lipaemia and other metabolic responses to a high-fat mixed test meal. Nine healthy, normotriacylglycerolaemic, free-living male volunteers (aged 35-60 years) completed the randomized, controlled, single-blind, crossover study. The study consisted of two periods (each of 22 d) of dietary intervention, separated by a 5-month washout period. During these two periods the subjects were provided with the manufactured foods enriched with EPA and DHA (n-3 enriched) or identical but unenriched foods (control). A mixed test meal containing 82 g fat was given to the fasted subjects on day 22 of each dietary intervention period. Two fasting, and thereafter hourly, blood samples were collected from the subjects for an 8 h period postprandially. Plasma triacylglycerol, total and HDL-cholesterol, non-esterified fatty acids (NEFA), glucose and immunoreactive insulin levels, post-heparin lipoprotein lipase (EC 3.1.1.34) activity and the plasma free fatty acid and phospholipid fatty acid compositions were measured. A mean daily intake of 1.4 g EPA+DHA (0.9 g EPA, 0.5 g DHA) was ingested during the n-3-enriched dietary period, which was significantly higher than the intake during the habitual and control periods (P < 0.001) assessed by a 3 d weighed food intake. A significantly higher level of EPA+DHA enrichment of the plasma fatty acids and phospholipids (P < 0.001) after the n-3-enriched compared with the control intervention periods was also found. The energy intake on both of the dietary intervention periods was found to be significantly higher than on the habitual diet (P < 0.001), with an increase in body weight of the subjects, which reached

  6. Environmental enrichment for laboratory rodents.

    PubMed

    Hutchinson, Eric; Avery, Anne; Vandewoude, Sue

    2005-01-01

    Modernization of housing and husbandry techniques for rodents has minimized confounding variables. The result has been vastly improved health maintenance and reproducibility of research findings, advances that have decreased the numbers of animals needed to attain statistically significant results. Even though not all aspects of rodent manipulation have been strictly defined, as housing and handling procedures have become increasingly standardized, many animal care personnel have recognized the lack of complexity of the rodents' environment. Concern for this aspect of animal well-being has led many research facilities to provide "environmental enrichment" for rodents. Additionally, regulatory agencies in the United States and Europe have also been increasingly concerned about this issue relative to laboratory animal husbandry. However, little is known about the influence such husbandry modifications may have on biological parameters. In this article, laws and guidelines relating to rodent enrichment are reviewed, the natural behaviors of select rodent species are discussed, and an overview of widely used types of enrichment in laboratory rodent management is provided. The literature evaluating effects of rodent enrichment is reviewed both in terms of neurological development and as an experimental variable, and results of a study evaluating the effect of enrichment on immune and physiological parameters are reported. Survey data on current enrichment practices in a large multi-institutional organization are presented, and practical aspects requiring consideration when devising a rodent enrichment program are discussed.

  7. 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.

  8. Preparation of magnetite/poly(styrene-divinylbenzene) nanoparticles for selective enrichment-determination of fenitrothion in environmental and biological samples.

    PubMed

    Eskandari, Habibollah; Naderi-Darehshori, Ali

    2012-09-19

    In the present study, a cross-linked nano-sized spherical magnetic poly(styrene-divinylbenzene) is synthesized and used as an adsorbent for enrichment-determination of fenitrothion. A miniemulsion polymerization procedure was used to prepare the adsorbent. The magnetic adsorbent was characterized by FT-IR, SEM and TEM. The prepared magnetic adsorbent nanoparticles were mixed with magnetite nanoparticles for faster and more efficient magnetic precipitation. The reduced fenitrothion was coupled with 3-methyl-2-benzothiazolinone hydrazone and then the blue colored complex was extracted. The blue derivative of fenitrothion was eluted by a 1 mL aliquot of 1-propanol prior to spectrophotometry at 571 nm. Beer's law was obeyed in the range of 2-230 ng mL(-1) of fenitrothion with relative standard deviation and recovery in the ranges of 0.9-5.1% and 97.2-100.0%, respectively. Selectivity of the method was evaluated, and the method was successfully applied to the determination of fenitrothion in various water, soil, urine and human plasma samples.

  9. 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.

  10. Facile synthesis of Fe3O4@mesoporous TiO2 microspheres for selective enrichment of phosphopeptides for phosphoproteomics analysis.

    PubMed

    Lu, Jin; Wang, Mengyi; Deng, Chunhui; Zhang, Xiangmin

    2013-02-15

    Protein phosphorylation is one of the most important post-translational modifications. Due to the dynamic nature and low stoichiometry of the protein phosphorylation, enrichment of phosphopeptides from proteolytic mixtures is necessary prior to their characterization by mass spectrometry. In this work, we synthesized Fe3O4@mesoporous TiO2 magnetic microspheres with core-shell structure and large surface area for selective enrichment of phosphopeptides. To demonstrate its ability for selective enrichment of phosphopeptides, we applied Fe3O4@mesoporous TiO2 magnetic microspheres to isolation and enrichment of the phosphopeptides from tryptic digestion of standard proteins and real samples, and then the enriched peptides were analyzed by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) or liquid chromatography coupled to electrospray ionization mass spectrometry (LC-ESI-MS). Due to that the as-made Fe3O4@mesoporous TiO2 microspheres have large surface area, good dispersivity and biocompatibility, they have been demonstrated as a powerful tool for phosphoproteomics research. PMID:23597982

  11. Environmental enrichment increases doublecortin-associated new neurons and decreases neuronal death without modifying anxiety-like behavior in mice chronically exposed to toluene.

    PubMed

    Paez-Martinez, Nayeli; Flores-Serrano, Zoraida; Ortiz-Lopez, Leonardo; Ramirez-Rodriguez, Gerardo

    2013-11-01

    Toluene misuse is a health problem worldwide with broad effects at the level of the central nervous system; however, therapeutic alternatives for inhalant abusers are limited. Chronic use of volatile substances is associated with different neurological and cognitive alterations, being anxiety a psychiatric condition with high prevalence. At cellular level toluene reduces neurogenesis and induces neuronal death. On the other hand, environmental enrichment has demonstrated to produce positive effects at behavioral and neuronal levels. Thus, the aim of the present work was to model alterations occasioned after repeated exposure to toluene (anxiety, reduction in neurogenesis - measured as doublecortin-labeled cells - and neuronal death). Subsequently, the influence of environmental enrichment on these effects was evaluated. Adolescent mice were exposed to toluene vapors from 1 to 4 weeks. Effects on anxiety were evaluated with the burying behavior test, whereas neurogenesis and hippocampal cell death were analyzed with immunohistochemistry, using anti-doublecortin or anti-active-Caspase-3 antibodies, respectively. Results showed that chronic toluene exposure increased anxiety in the burying behavior test; additionally, toluene decreased neurogenesis and enhanced neuronal death. Environmental enrichment (EE) enhanced the anxiety like response in air-exposed mice but did not modify the toluene anxiety response. Additionally, EE enhanced neurogenesis in toluene-pretreated animals at the same level to that found in animals unexposed to toluene and decreased neuronal death. Overall, the present study showed that environmental enrichment positively impacts some effects produced by repeated exposure to toluene.

  12. 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

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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...

  1. On-line selective enrichment and ion-pair reaction for structural determination of sulfated glycopeptides by capillary electrophoresis-mass spectrometry.

    PubMed

    Imami, Koshi; Ishihama, Yasushi; Terabe, Shigeru

    2008-06-20

    We describe a new capillary electrophoresis-mass spectrometry (CE-MS)-based technique for analyzing sulfated glycopeptides. The proposed method performs selective enrichment of sulfated glycopeptides from a complex mixture of peptides based on field-enhanced sample injection and ion-pair reaction with a basic ion-pair reagent (Lys-Lys-Lys; KKK) at the exit end of a capillary in a single analysis, which permits successful fragmentation of sulfated glycopeptides in positive-ion mode at the MS/MS stage for comprehensive structural analysis. In this study, the method was verified using a model sulfated monosaccharide, N-acetyl-d-galactosamine 4-sulfate (GalNAc 4S). As an example of an application of this method, sulfated glycopeptides were selectively enriched from the enzymatic digest of thyroid stimulating hormone, affording approximately 500-fold sensitivity enhancement, and structural information was successfully obtained via on-line ion-pair complexation reaction.

  2. Granulosa cells and retinoic acid co-treatment enrich potential germ cells from manually selected Oct4-EGFP expressing human embryonic stem cells.

    PubMed

    Chen, Hsin-Fu; Jan, Pey-Shynan; Kuo, Hung-Chih; Wu, Fang-Chun; Lan, Chen-Wei; Huang, Mei-Chi; Chien, Chung-Liang; Ho, Hong-Nerng

    2014-09-01

    Differentiation of human embryonic stem (HES) cells to germ cells may become clinically useful in overcoming diseases related to germ-cell development. Niches were used to differentiate HES cell lines, NTU1 and H9 Oct4-enhanced green fluorescence protein (EGFP), including laminin, granulosa cell co-culture or conditioned medium, ovarian stromal cell co-culture or conditioned medium, retinoic acid, stem cell factor (SCF) and BMP4-BMP7-BMP8b treatment. Flow cytometry showed that granulosa cell co-culture (P < 0.001) or conditioned medium (P = 0.007) treatment for 14 days significantly increased the percentages of differentiated H9 Oct4-EGFP cells expressing early germ cell marker stage-specific embryonic antigen 1(SSEA1); sorted SSEA1[+] cells did not express higher levels of germ cell gene VASA and GDF9. Manually collected H9 Oct4-EGFP[+] cells expressed significantly higher levels of VASA (P = 0.005) and GDF9 (P = 0.001). H9 Oct4-EGFP[+] cells developed to ovarian follicle-like structures after culture for 28 days but with low efficiency. Unlike SCF and BMP4, retinoic acid co-treatment enhanced VASA, GDF9 and SCP3 expression. A protocol is recommended to enrich differentiated HES cells with germ-cell potential by culture with granulosa cells, conditioned medium or retinoic acid, manual selection of Oct4-EGFP[+] cells, and analysis of VASA, GDF9 expression, or both.

  3. Increased Selection Response in Larger Populations. II. Selection for Ethanol Vapor Resistance in Drosophila Melanogaster at Two Population Sizes

    PubMed Central

    Weber, K. E.; Diggins, L. T.

    1990-01-01

    The effect of large population size on selection response was investigated using Drosophila melanogaster, with four ``small'' lines of 160 selected parents/generation compared to two ``large'' lines of 1600 selected parents/generation. All lines were selected under similar conditions at a selection intensity of approximately 0.55 standard deviations, for 65 generations, for increased ethanol vapor resistance (measured in minutes required to become anesthetized). Two unselected control lines of 320 parents/generation were also maintained. A significant effect of population size was found. The final treatment means and standard errors were: 27.91 +/- 1.28 min (two ``large'' lines); 19.40 +/- 1.54 min (four ``small'' lines); and 4.98 +/- 0.35 min (two control lines). To estimate the mutation rate for the trait, two isogenic lines of about 400 selected parents were selected for 29 generations. The mean increase in additive genetic variance per generation was 0.0009 times the initial environmental variance of the outbred lines. This is comparable to other reported mutation rates. Mutation can explain part of the difference in evolved resistance between treatments, but it appears that even at rather large population sizes, a large difference in long-term response can be obtained in larger outbred lines, from more complete utilization of the initial genetic variation. PMID:2116359

  4. Increased Selection Response in Larger Populations. I. Selection for Wing-Tip Height in Drosophila Melanogaster at Three Population Sizes

    PubMed Central

    Weber, K. E.

    1990-01-01

    The effect of population size on selection response was investigated with replicated selection lines of 40, 200 and 1000 selected parents, using Drosophila melanogaster homozygous for the mutant raised. Selection for increased wing-tip height was carried out for 55 generations, with an average selection intensity of 0.6 standard deviation. The rank order of responses in the seven individual lines was significantly in order of population size, and the variance of response among lines showed a significant effect of population size. The final mean responses (selected - controls, +/- standard errors) in the three treatments, in order of increasing population size, were 8.6 +/- 1.8 mils (three small lines), 15.1 +/- 1.3 mils (two medium lines), and 19.8 +/- 1.5 mils (two large lines). The differences between treatments seem to have emerged too rapidly to be the result of mutations, and are probably due mainly to the utilization of existing variation with greater efficiency by selection in larger populations. PMID:2116358

  5. Short-term environmental enrichment, in the absence of exercise, improves memory, and increases NGF concentration, early neuronal survival, and synaptogenesis in the dentate gyrus in a time-dependent manner.

    PubMed

    Birch, Amy M; McGarry, Niamh B; Kelly, Aine M

    2013-06-01

    Environmental manipulations can enhance neuroplasticity in the brain, with enrichment-induced cognitive improvements being linked to increased expression of growth factors, such as neurotrophins, and enhanced hippocampal neurogenesis. There is, however, a great deal of variation in environmental enrichment protocols used in the literature, making it difficult to assess the role of particular aspects of enrichment upon memory and the underlying associated mechanisms. This study sought to evaluate the efficacy of environmental enrichment, in the absence of exercise, as a cognitive enhancer and assess the role of Nerve Growth Factor (NGF), neurogenesis and synaptogenesis in this process. We report that rats housed in an enriched environment for 3 and 6 weeks (wk) displayed improved recognition memory, while rats enriched for 6 wk also displayed improved spatial and working memory. Neurochemical analyses revealed significant increases in NGF concentration and subgranular progenitor cell survival (as measured by BrdU+ nuclei) in the dentate gyrus of rats enriched for 6 wk, suggesting that these cellular changes may mediate the enrichment-induced memory improvements. Further analysis revealed a significant positive correlation between recognition task performance and BrdU+ nuclei. In addition, rats enriched for 6 wk showed a significant increase in expression of synaptophysin and synapsin I in the dentate gyrus, indicating that environmental enrichment can increase synaptogenesis. These data indicate a time-dependent cognitive-enhancing effect of environmental enrichment that is independent of physical activity. These data also support a role for increased concentration of NGF in dentate gyrus, synaptogenesis, and neurogenesis in mediating this effect.

  6. 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.

  7. Behavioral Traits are Affected by Selective Breeding for Increased Wheel-Running Behavior in Mice

    PubMed Central

    Jónás, I.; Schubert, K. A.; Reijne, A. C.; Scholte, J.; Garland, T.; Gerkema, M. P.; Scheurink, A. J. W.; Nyakas, C.

    2010-01-01

    Voluntary physical activity may be related to personality traits. Here, we investigated these relations in two mouse lines selectively bred for high voluntary wheel-running behavior and in one non-selected control line. Selection lines were more explorative and “information gathering” in the open-field test, either with increased upright positions or horizontal locomotion toward the middle ring. Furthermore, one of the selection lines had an increased risk-taking behavior relative to the control line in approaching a novel object placed in the center of the open field. However, anxiety behavior was increased in selection lines during the plus-maze test. Maze learning was not statistically different among lines, but routine behavior was increased in both selection lines when the maze exit after 2 days of testing was displaced. Specifically, in the displaced maze, selected mice traveled more frequently to the old, habituated exit, bypassing the new exit attached to their home cage. Although the generality of the results would need to be confirmed in future studies including all eight lines in the selection experiment, the increased routine and exploratory behavior (at least in the lines used in the present study) may be adaptive to sustain high activity levels. PMID:20369280

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

    PubMed

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

    1996-11-01

    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.

  9. 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

  10. 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

  11. 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

  12. 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

  13. Molecularly imprinted polymers with synthetic dummy template for simultaneously selective removal and enrichment of ginkgolic acids from Ginkgo biloba L. leaves extracts.

    PubMed

    Ji, Wenhua; Ma, Xiuli; Xie, Hongkai; Chen, Lingxiao; Wang, Xiao; Zhao, Hengqiang; Huang, Luqi

    2014-11-14

    Dummy molecularly imprinted polymers (DMIPs) for simultaneously selective removal and enrichment of ginkgolic acids (GAs) during the processing of Ginkgo biloba leaves have been prepared. Two dummy template molecule with similar structural skeleton to GAs, 6-methoxysalicylic acid (MOSA, DT-1) and 6-hexadecyloxysalicylic acid (HOSA, DT-2), have been designed and synthesized. The performance of the DMIPs and NIPs were evaluated including selective recognition capacity, adsorption isotherm, and adsorption kinetics. The selective recognition capacity of the three GAs with four analogues on the sorbents illustrated that the DMIPs sorbents have high specificity for GAs. An efficient method based on DMIP-HOSA coupled with solid-phase extraction (SPE) was developed for simultaneously selective removal and enrichment of ginkgolic acids (GAs) during the processing of Ginkgo biloba leaves. The method showed excellent recoveries (82.5-88.7%) and precision (RSD 0.5-2.6%, n=5) for licorice extracts, Gastrodia elata extracts and pepper extracts spiked at three concentration levels each (50, 100, 200 μg mL(-1)). The results indicated that GAs and standardized Ginkgo biloba leaves extracts could be obtained simultaneously through the DMIP-SPE.

  14. 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.

  15. Use of a lag differential reinforcement contingency to increase varied selections of classroom activities.

    PubMed

    Cammilleri, Anthony P; Hanley, Gregory P

    2005-01-01

    The present study evaluated the effects of a lag differential reinforcement contingency on 2 students' activity selections using reversal designs. Results showed that the lag contingency was responsible for promoting increased novel selections, engagement in diverse activities, and greater progress with respect to programmed academic activities.

  16. 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...

  17. Use of a Lag Differential Reinforcement Contingency to Increase Varied Selections of Classroom Activities

    ERIC Educational Resources Information Center

    Cammilleri, Anthony P.; Hanley, Gregory P.

    2005-01-01

    The present study evaluated the effects of a lag differential reinforcement contingency on 2 students' activity selections using reversal designs. Results showed that the lag contingency was responsible for promoting increased novel selections, engagement in diverse activities, and greater progress with respect to programmed academic activities.

  18. 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

  19. Organic matter production response to CO2 increase in open subarctic plankton communities: Comparison of six microcosm experiments under iron-limited and -enriched bloom conditions

    NASA Astrophysics Data System (ADS)

    Yoshimura, Takeshi; Sugie, Koji; Endo, Hisashi; Suzuki, Koji; Nishioka, Jun; Ono, Tsuneo

    2014-12-01

    Increase in seawater pCO2 and the corresponding decrease in pH caused by the increasing atmospheric CO2 concentration (i.e., ocean acidification) may affect organic matter production by phytoplankton communities. Organic matter production forms the basis of marine food webs and plays a crucial role in oceanic CO2 uptake through the biological carbon pump, and hence will potentially affect future marine ecosystem dynamics. However, responses of organic matter production in open ocean plankton ecosystems to CO2 increase have not been fully examined. We conducted on-deck microcosm experiments using high nutrient, low chlorophyll (HNLC) waters in the western subarctic Pacific and oceanic Bering Sea basin in summer 2008 and 2009, respectively, to examine the impacts of elevated CO2 on particulate and dissolved organic matter (i.e., POM and DOM, respectively) production. Iron deficient natural plankton communities were incubated for 7-14 days under multiple CO2 levels with and without iron enrichments (hereafter +Fe and -Fe treatments, respectively). By combining with our previous experiments at two sites, we created a comprehensive dataset on responses of organic matter production to CO2 increase during macronutrient replete conditions in HNLC waters. Significant differences in net particulate organic carbon production among CO2 treatments were observed only in the -Fe treatments, whereas that in net dissolved organic carbon production were mainly observed in the +Fe treatments, suggesting that CO2 may affect different processes depending on the Fe nutritional status. However, impacts of CO2 were not consistent among experiments and were much smaller than the consistent positive effects of Fe enrichment. In contrast, no significant differences among the CO2 treatments were observed for organic carbon partitioning into POM and DOM, and carbon to nitrogen ratio of net produced POM. We conclude that CO2 does not play a primary role, but could have secondary effects on

  20. Increased liver carcinogenesis and enrichment of stem cell properties in livers of Dickkopf 2 (Dkk2) deleted mice.

    PubMed

    Maass, Thorsten; Marquardt, Jens; Lee, Ju-Seog; Krupp, Markus; Scholz-Kreisel, Peter; Mogler, Carolin; Schirmacher, Peter; Müller, Martina; Westphal, Heiner; Galle, Peter R; Teufel, Andreas

    2016-05-17

    Dkk2 a antagonist of the Wnt/β-catenin-signaling pathway was shown to be silenced in diverse cancers. More recent data indicate that Dkk family members may also possess functions independent of Wnt-signaling during carcinogenesis. The detailed biological function of Dkks and its relevance for liver cancer is unknown. We analyzed the effects of a genetic deletion of Dkk2 (Dkk2-/-) in a hepatocarcinogenesis model using DEN/Phenobarbital. Untreated Dkk2-/- animals, showed considerable atypia with variation of hepatocyte size and chromatin density. In livers of Dkk2-/- mice nodule formation was seen at 9 months of age with focal loss of trabecular architecture and atypical hepatocytes and after DEN induction Dkk2-/- mice developed significantly more liver tumors compared to controls. Whole transcriptome analysis of untreated Dkk2-/- liver tissue revealed a Dkk2-dependent genetic network involving Wnt/β-Catenin but also multiple additional oncogenic factors, such as e.g. Pdgf-b, Gdf-15 and Hnf4a. Dkk2-/- tumor cells showed a significant deregulation of stemness genes associated with enhanced colony forming properties. Integration of the Dkk2-/- signature into human data was strongly associated with patients survival. Dkk2 deletion results in alterations of liver morphology leading to an increased frequency of liver cancer. The associated genetic changes included factors not primarily related to Wnt/β-Catenin-signaling and correlated with the clinical outcome of HCC-patients.

  1. Increased liver carcinogenesis and enrichment of stem cell properties in livers of Dickkopf 2 (Dkk2) deleted mice

    PubMed Central

    Maass, Thorsten; Marquardt, Jens; Lee, Ju-Seog; Krupp, Markus; Scholz-Kreisel, Peter; Mogler, Carolin; Schirmacher, Peter; Müller, Martina; Westphal, Heiner; Galle, Peter R.; Teufel, Andreas

    2016-01-01

    Dkk2 a antagonist of the Wnt/β-catenin-signaling pathway was shown to be silenced in diverse cancers. More recent data indicate that Dkk family members may also possess functions independent of Wnt-signaling during carcinogenesis. The detailed biological function of Dkks and its relevance for liver cancer is unknown. We analyzed the effects of a genetic deletion of Dkk2 (Dkk2−/−) in a hepatocarcinogenesis model using DEN/Phenobarbital. Untreated Dkk2−/− animals, showed considerable atypia with variation of hepatocyte size and chromatin density. In livers of Dkk2−/− mice nodule formation was seen at 9 months of age with focal loss of trabecular architecture and atypical hepatocytes and after DEN induction Dkk2−/− mice developed significantly more liver tumors compared to controls. Whole transcriptome analysis of untreated Dkk2−/− liver tissue revealed a Dkk2-dependent genetic network involving Wnt/β-Catenin but also multiple additional oncogenic factors, such as e.g. Pdgf-b, Gdf-15 and Hnf4a. Dkk2−/− tumor cells showed a significant deregulation of stemness genes associated with enhanced colony forming properties. Integration of the Dkk2−/− signature into human data was strongly associated with patients survival. Dkk2 deletion results in alterations of liver morphology leading to an increased frequency of liver cancer. The associated genetic changes included factors not primarily related to Wnt/β-Catenin-signaling and correlated with the clinical outcome of HCC-patients. PMID:25826080

  2. 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

  3. 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

  4. Molecularly imprinted SPE coupled with HPLC for the selective separation and enrichment of alkyl imidazolium ionic liquids in environmental water samples.

    PubMed

    Xia, Gao; Jing, Fan; Guifen, Zhu; Xiaolong, Wang; Jianji, Wang

    2013-10-01

    A novel 1-butyl-3-methylimidazolium chloride ionic liquid surface imprinted solid-phase sorbent was synthesized. The as-prepared material was characterized by SEM, Brunauer-Emmett-Teller surface area analysis and Fourier Transform IR measurements. Then its adsorption properties for alkyl imidazolium ionic liquids, including adsorption capacities, adsorption kinetics, and properties of selective separation and enrichment were studied in detail. It was shown that the ionic liquid surface imprinted polymer exhibited high selective recognition characteristics for the imidazolium chloride ionic liquids with short alkyl chains (C(n)mimCl, n = 2, 4, 6, 8) and the adsorption equilibrium was achieved within 25 min. Various parameters were optimized for the 1-butyl-3-methylimidazolium chloride ionic liquid surface imprinted polymer SPE column, such as flow rate, eluent solvent, selectivity, and reusability of the column. Then, the SPE column coupled with HPLC was used for the determination of alkyl imidazolium ionic liquids. Experimental results showed that the existence of their structural analogs and common concomitants in environmental matrices did not affect the enrichment of 1-butyl-3-methyl imidazolium chloride ionic liquid. The average recoveries of 1-butyl-3-methylimidazolium chloride ionic liquid in spiked water samples were in the range of 92.0-102.0% with the RSD lower than 5.8%.

  5. 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

  6. SEL, a Selective Enrichment Broth for Simultaneous Growth of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes▿ †

    PubMed Central

    Kim, Hyochin; Bhunia, Arun K.

    2008-01-01

    Multipathogen detection on a single-assay platform not only reduces the cost for testing but also provides data on the presence of pathogens in a single experiment. To achieve this detection, a multipathogen selective enrichment medium is essential to allow the concurrent growth of pathogens. SEL broth was formulated to allow the simultaneous growth of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes. The results were compared to those obtained with the respective individual selective enrichment broths, Rappaport-Vassiliadis (RV) for S. enterica, modified E. coli broth with 20 mg of novobiocin/liter for E. coli O157:H7, and Fraser broth for L. monocytogenes, and a currently used universal preenrichment broth (UPB). The growth of each pathogen in SEL inoculated at 101 or 103 CFU/ml was superior to that in the respective individual enrichment broth, except in the case of RV, in which Salmonella cells inoculated at both concentrations grew equally well. In mixed-culture experiments with cells of the three species present in equal concentrations or at a 1:10:1,000 ratio, the overall growth was proportional to the initial inoculation levels; however, the growth of L. monocytogenes was markedly suppressed when cells of this species were present at lower concentrations than those of the other two species. Further, SEL was able to resuscitate acid- and cold-stressed cells, and recovery was comparable to that in nonselective tryptic soy broth containing 6% yeast extract but superior to that in the respective individual selective broths. SEL promoted the growth of all three pathogens in a mixture in ready-to-eat salami and in turkey meat samples. Moreover, each pathogen was readily detected by a pathogen-specific immunochromatographic lateral-flow or multiplex PCR assay. Even though the growth of each pathogen in SEL was comparable to that in UPB, SEL inhibited greater numbers of nontarget organisms than did UPB. In summary, SEL was demonstrated to

  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. Selection for increased voluntary wheel-running affects behavior and brain monoamines in mice.

    PubMed

    Waters, R Parrish; Pringle, R B; Forster, G L; Renner, K J; Malisch, J L; Garland, T; Swallow, J G

    2013-05-01

    Selective-breeding of house mice for increased voluntary wheel-running has resulted in multiple physiological and behavioral changes. Characterizing these differences may lead to experimental models that can elucidate factors involved in human diseases and disorders associated with physical inactivity, or potentially treated by physical activity, such as diabetes, obesity, and depression. Herein, we present ethological data for adult males from a line of mice that has been selectively bred for high levels of voluntary wheel-running and from a non-selected control line, housed with or without wheels. Additionally, we present concentrations of central monoamines in limbic, striatal, and midbrain regions. We monitored wheel-running for 8 weeks, and observed home-cage behavior during the last 5 weeks of the study. Mice from the selected line accumulated more revolutions per day than controls due to increased speed and duration of running. Selected mice exhibited more active behaviors than controls, regardless of wheel access, and exhibited less inactivity and grooming than controls. Selective-breeding also influenced the longitudinal patterns of behavior. We found statistically significant differences in monoamine concentrations and associated metabolites in brain regions that influence exercise and motivational state. These results suggest underlying neurochemical differences between selected and control lines that may influence the observed differences in behavior. Our results bolster the argument that selected mice can provide a useful model of human psychological and physiological diseases and disorders. PMID:23352668

  9. 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

  10. 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.

  11. 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

  12. 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

  13. Laboratory selection for increased tolerance to niclosamide in Bulinus truncatus (Gastropoda: Planorbidae) from Iran.

    PubMed

    Jelnes, J E

    1987-04-01

    Survivors of Bulinus truncatus from one exposure to niclosamide (Bayluscide) were used to establish the next generation in a five generation long laboratory selection for increased tolerance to niclosamide. In a comparison of the tolerance to the molluscicide between two original and two selected strains about 150 snails of each strain, divided into four size-groups, were exposed to aliquots of the same niclosamide solution on the same day and during the same time of the day. It was shown that five generations of relatively mild selection (30-50% survival) resulted in a significant increased tolerance to niclosamide in snails with only one exposure before start of the selection procedure. A comparison with published data indicated that the unselected strains did not change their tolerance to niclosamide during seven years of laboratory breeding. The strain exposed to niclosamide once in each of 16 generations showed an avoidance reaction to the chemical by crawling out of the water.

  14. Development of a real-time PCR method coupled with a selective pre-enrichment step for quantification of Morganella morganii and Morganella psychrotolerans in fish products.

    PubMed

    Podeur, Gaëtan; Dalgaard, Paw; Leroi, Francoise; Prévost, Hervé; Emborg, Jette; Martinussen, Jan; Hansen, Lars Hestbjerg; Pilet, Marie-France

    2015-06-16

    Histamine fish poisoning is common and due to toxic concentrations of histamine often produced by Gram-negative bacteria in fin-fish products with a high content of the free amino acid histidine. The genus Morganella includes two species previously reported to cause incidents of histamine fish poisoning. Morganella morganii and Morganella psychrotolerans are both strong producer of histamine. However, little is known about the occurrence and critical stages for fish contamination with these bacteria. To elucidate contamination routes of Morganella, specific real-time quantitative PCR (RTi qPCR) methods for quantification of M. morganii and M. psychrotolerans have been developed. Selective primers amplified a 110 bp region of the vasD gene for M. psychrotolerans and a 171 bp region of the galactokinase gene for M. morganii. These primer-sets showed high specificity as demonstrated by using purified DNA from 23 other histamine producing bacteria and 26 isolates with no or limited histamine production. The efficiency of the qPCR reactions on artificially contaminated fish samples were 100.8% and 96.3% respectively. The limit of quantification (LOQ) without enrichment was 4 log CFU/g. A quantitative enrichment step with a selective medium was included and improved the sensitivity of the methods to a LOQ of below 50 CFU/g in seafood. RTi qPCR methods with or without enrichment were evaluated for enumeration of Morganella species in naturally contaminated fresh fish and lightly preserved seafood from Denmark. These new methods will contribute to a better understanding of the occurrence and histamine production by Morganella species in fish products, information that is essential to reduce the unacceptably high frequency of histamine fish poisoning.

  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.

  17. 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.

  18. 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.

  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. 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

  1. 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

  2. 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

    2016-06-16

    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.

  3. 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

  4. Distribution, enrichment, and source identification of selected heavy metals in surface sediments of the Siran River, Mansehra, Pakistan.

    PubMed

    Raza, Ahmed; Farooqi, Abida; Javed, Asif; Ali, Waqar

    2016-10-01

    To assess the trace metal pollution in the Siran River, sediments were collected from 12 sites, from the left and right banks of the river in 2013. The concentrations, accumulation, distribution pattern, and pollution status of heavy metals in sediments were investigated using geoaccumulation index (I geo) and enrichment factor (EF). The toxic risk of heavy metals was assessed using interim sediment quality guidelines (ISQGs), portable effect level (PEL), threshold effect level (TEL), and toxic effect threshold (TET). I geo and EF values showed that sediments were loaded with Ni, Cd, Pb, and Co and no obvious variations were found among the left and right banks of the river. The EF and I geo values were found in order of Co > Pb > Ni > As > Cd > Cu > Zn > Fe and Cd > Co > Pb > Ni > As > Fe > Zn > Cu > Mn, respectively. Furthermore, multivariate statistical analysis like inter-metal correlation, cluster analysis (CA), and principal component analysis (PCA) results revealed that geogenic and anthropogenic activities were major sources of sediment contamination in the study area. These results indicated that more attention should be paid to the inner loads of sediment in order to achieve improvements in reservoir water quality after the control of external pollution. PMID:27640167

  5. 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

  6. 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.

  7. Genome Evolution in the Cold: Antarctic Icefish Muscle Transcriptome Reveals Selective Duplications Increasing Mitochondrial Function

    PubMed Central

    Coppe, Alessandro; Agostini, Cecilia; Marino, Ilaria A.M.; Zane, Lorenzo; Bargelloni, Luca; Bortoluzzi, Stefania; Patarnello, Tomaso

    2013-01-01

    Antarctic notothenioids radiated over millions of years in subzero waters, evolving peculiar features, such as antifreeze glycoproteins and absence of heat shock response. Icefish, family Channichthyidae, also lack oxygen-binding proteins and display extreme modifications, including high mitochondrial densities in aerobic tissues. A genomic expansion accompanying the evolution of these fish was reported, but paucity of genomic information limits the understanding of notothenioid cold adaptation. We reconstructed and annotated the first skeletal muscle transcriptome of the icefish Chionodraco hamatus providing a new resource for icefish genomics (http://compgen.bio.unipd.it/chamatusbase/, last accessed December 12, 2012). We exploited deep sequencing of this energy-dependent tissue to test the hypothesis of selective duplication of genes involved in mitochondrial function. We developed a bioinformatic approach to univocally assign C. hamatus transcripts to orthology groups extracted from phylogenetic trees of five model species. Chionodraco hamatus duplicates were recorded for each orthology group allowing the identification of duplicated genes specific to the icefish lineage. Significantly more duplicates were found in the icefish when transcriptome data were compared with whole-genome data of model species. Indeed, duplicated genes were significantly enriched in proteins with mitochondrial localization, involved in mitochondrial function and biogenesis. In cold conditions and without oxygen-carrying proteins, energy production is challenging. The combination of high mitochondrial densities and the maintenance of duplicated genes involved in mitochondrial biogenesis and aerobic respiration might confer a selective advantage by improving oxygen diffusion and energy supply to aerobic tissues. Our results provide new insights into the genomic basis of icefish cold adaptation. PMID:23196969

  8. 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…

  9. 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…

  10. 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.

  11. Selectivity of silymarin on the increase of the glutathione content in different tissues of the rat.

    PubMed

    Valenzuela, A; Aspillaga, M; Vial, S; Guerra, R

    1989-10-01

    Silymarin, a flavonoid extracted from the seeds of the milk thistle, Silybum marianum, increases the redox state and the total glutathione content of the liver, intestine, and stomach of the rat. The same treatment does not affect the levels of the tripeptides in the kidney, lung, and spleen. This selective effect of the flavonoid on the digestive organs is ascribed to its pharmacokinetics on the digestive track, where the biliary concentration of silymarin is increased and maintained via the entero-hepatic circulation.

  12. 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...

  13. 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...

  14. 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.

  15. 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

  16. Higher vitamin D intake in preterm infants fed an isocaloric, protein- and mineral-enriched postdischarge formula is associated with increased bone accretion.

    PubMed

    van de Lagemaat, Monique; Rotteveel, Joost; Schaafsma, Anne; van Weissenbruch, Mirjam M; Lafeber, Harrie N

    2013-09-01

    During the first half of infancy, bone accretion in preterm infants fed an isocaloric, protein- and mineral-enriched postdischarge formula (PDF) is higher compared with those fed term formula (TF) or human milk (HM). This may be related to higher protein, calcium, phosphorus, and vitamin D intakes. This study investigated serum calcium, phosphate, and 25-hydroxyvitamin D [25(OH)D] in relation to bone mineral content (BMC) in PDF-, TF-, and HM-fed preterm infants between term age (40 wk postmenstrual age) and 6 mo corrected age (CA). Between term age and 6 mo CA, 52 preterm infants were fed PDF (per 100 mL: 67 kcal, 1.7 g protein, 65 mg calcium, 38 mg phosphorus, 56 IU vitamin D), 41 were fed TF (per 100 mL: 67 kcal, 1.47 g protein, 50 mg calcium, 30 mg phosphorus, 48 IU vitamin D), and 46 were fed HM. Serum calcium, phosphorus, and 25(OH)D were measured at term age and at 3 and 6 mo CA. BMC (g) was measured by whole-body dual-energy X-ray absorptiometry at term age and at 6 mo CA. Between term age and 6 mo CA, intakes of calcium, phosphorus, and vitamin D were significantly higher in PDF- compared with TF-fed infants, and PDF-fed infants reached significantly higher serum 25(OH)D concentrations at 6 mo CA (103 ± 24.3 vs. 92.8 ± 15.5 nmol/L, P = 0.003). Between term age and 6 mo CA, increases in serum 25(OH)D were associated with an increase in BMC (β = 0.001; 95% CI: 0.00, 0.003; P = 0.046). In conclusion, during the first 6 mo postterm, higher vitamin D intake and greater increase in serum 25(OH)D concentration in PDF-fed preterm infants were associated with increased bone accretion.

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

    PubMed

    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.

  18. [A novel solid phase extraction column combined with ultra performance liquid chromatography/tandem mass spectrometry for selective enrichment and determination of clenbuterol in pork].

    PubMed

    Meng, Wenying; Guo, Zhimou; Shen, Weijian; Shen, Chongyu; Wu, Bin; Liu, Yanming; Zhang, Feifang; Liang, Xinmiao

    2012-02-01

    A simple and efficient method based on a novel solid phase extraction (SPE) cartridge and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) was developed for the determination of clenbuterol residue in pork. The minced pork sample was ultrasonically extracted by 5% (v/v) perchloric acid and centrifuged at 10 000 r/min for 15 min, then the supernatant was purified by an SMCX cartridge, which is a novel SPE column based on homemade silica matrix with two mixed modes of reversed-phase and strong cation exchange, for the selective enrichment and purification of the analyte. The linear range of the method was 0.25 - 50 microg/kg with a correlation coefficient of 0.998 2. The average recoveries ranged from 62.2% to 72.0% at the three spiked levels of 1.25, 12.5 and 50 microg/kg with the relative standard deviations (RSDs) between 4.2% and 6.1%. The limit of detection (S/N = 3) was 0.05 microg/kg. The method is simple, fast and can be extended to enrich and determine beta-agonist drugs.

  19. 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

  20. Environmental fluctuations do not select for increased variation or population-based resistance in Escherichia coli.

    PubMed

    Karve, Shraddha Madhav; Tiwary, Kanishka; Selveshwari, S; Dey, Sutirth

    2016-03-01

    Little is known about the mechanisms that enable organisms to cope with unpredictable environments. To address this issue, we used replicate populations of Escherichia coli selected under complex, randomly changing environments. Under four novel stresses that had no known correlation with the selection environments, individual cells of the selected populations had significantly lower lag and greater yield compared to the controls. More importantly, there were no outliers in terms of growth, thus ruling out the evolution of population-based resistance. We also assayed the standing phenotypic variation of the selected populations, in terms of their growth on 94 different substrates. Contrary to expectations, there was no increase in the standing variation of the selected populations, nor was there any significant divergence from the ancestors. This suggested that the greater fitness in novel environments is brought about by selection at the level of the individuals, which restricts the suite of traits that can potentially evolve through this mechanism. Given that day-to-day climatic variability of the world is rising, these results have potential public health implications. Our results also underline the need for a very different kind of theoretical approach to study the effects of fluctuating environments. PMID:26949086

  1. 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

  2. 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.

  3. 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

  4. 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.

  5. 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

  6. 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

  7. 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

  8. Strong artificial selection in domestic mammals did not result in an increased recombination rate.

    PubMed

    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

    2015-02-01

    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

  9. Nanometer surface roughness increases select osteoblast adhesion on carbon nanofiber compacts.

    PubMed

    Price, Rachel L; Ellison, Karen; Haberstroh, Karen M; Webster, Thomas J

    2004-07-01

    Carbon nanofibers have exceptional theoretical mechanical properties (such as low weight-to-strength ratios) that, along with possessing nanoscale fiber dimensions similar to crystalline hydroxyapatite found in bone, suggest strong possibilities for use as an orthopedic/dental implant material. To determine, for the first time, cytocompatibility properties pertinent for bone prosthetic applications, osteoblast (bone-forming cells), fibroblast (cells contributing to callus formation and fibrous encapsulation events that result in implant loosening), chondrocyte (cartilage-forming cells), and smooth muscle cell (for comparison purposes) adhesion were determined on carbon nanofibers in the present in vitro study. Results provided evidence that, compared to conventional carbon fibers, nanometer dimension carbon fibers promoted select osteoblast adhesion. Moreover, adhesion of other cells was not influenced by carbon fiber dimensions. In fact, smooth muscle cell, fibroblast, and chondrocyte adhesion decreased with an increase in either carbon nanofiber surface energy or simultaneous change in carbon nanofiber chemistry. To determine properties that selectively enhanced osteoblast adhesion, similar cell adhesion assays were performed on polymer (specifically, poly-lactic-co-glycolic; PLGA) casts of carbon fiber compacts previously tested. Compared to PLGA casts of conventional carbon fibers, results provided the first evidence of enhanced select osteoblast adhesion on PLGA casts of nanophase carbon fibers. The summation of these results demonstrate that due to a high degree of nanometer surface roughness, carbon fibers with nanometer dimensions may be optimal materials to selectively increase osteoblast adhesion necessary for successful orthopedic/dental implant applications.

  10. USING NEGATIVE REINFORCEMENT TO INCREASE SELF-FEEDING IN A CHILD WITH FOOD SELECTIVITY

    PubMed Central

    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 effectiveness of the intervention and implications for future research are discussed. PMID:22219540

  11. 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…

  12. Selecting informative subsets of sparse supermatrices increases the chance to find correct trees

    PubMed Central

    2013-01-01

    Background Character matrices with extensive missing data are frequently used in phylogenomics with potentially detrimental effects on the accuracy and robustness of tree inference. Therefore, many investigators select taxa and genes with high data coverage. Drawbacks of these selections are their exclusive reliance on data coverage without consideration of actual signal in the data which might, thus, not deliver optimal data matrices in terms of potential phylogenetic signal. In order to circumvent this problem, we have developed a heuristics implemented in a software called mare which (1) assesses information content of genes in supermatrices using a measure of potential signal combined with data coverage and (2) reduces supermatrices with a simple hill climbing procedure to submatrices with high total information content. We conducted simulation studies using matrices of 50 taxa × 50 genes with heterogeneous phylogenetic signal among genes and data coverage between 10–30%. Results With matrices of 50 taxa × 50 genes with heterogeneous phylogenetic signal among genes and data coverage between 10–30% Maximum Likelihood (ML) tree reconstructions failed to recover correct trees. A selection of a data subset with the herein proposed approach increased the chance to recover correct partial trees more than 10-fold. The selection of data subsets with the herein proposed simple hill climbing procedure performed well either considering the information content or just a simple presence/absence information of genes. We also applied our approach on an empirical data set, addressing questions of vertebrate systematics. With this empirical dataset selecting a data subset with high information content and supporting a tree with high average boostrap support was most successful if information content of genes was considered. Conclusions Our analyses of simulated and empirical data demonstrate that sparse supermatrices can be reduced on a formal basis outperforming the

  13. Selective Enrichment and Sequencing of Whole Mitochondrial Genomes in the Presence of Nuclear Encoded Mitochondrial Pseudogenes (Numts)

    PubMed Central

    Wolff, Jonci N.; Shearman, Deborah C. A.; Brooks, Rob C.; Ballard, John W. O.

    2012-01-01

    Numts are an integral component of many eukaryote genomes offering a snapshot of the evolutionary process that led from the incorporation of an α-proteobacterium into a larger eukaryotic cell some 1.8 billion years ago. Although numt sequence can be harnessed as molecular marker, these sequences often remain unidentified and are mistaken for genuine mtDNA leading to erroneous interpretation of mtDNA data sets. It is therefore indispensable that during the process of amplifying and sequencing mitochondrial genes, preventive measures are taken to ensure the exclusion of numts to guarantee the recovery of genuine mtDNA. This applies to mtDNA analyses in general but especially to studies where mtDNAs are sequenced de novo as the launch pad for subsequent mtDNA-based research. By using a combination of dilution series and nested rolling circle amplification (RCA), we present a novel strategy to selectively amplify mtDNA and exclude the amplification of numt sequence. We have successfully applied this strategy to de novo sequence the mtDNA of the Black Field Cricket Teleogryllus commodus, a species known to contain numts. Aligning our assembled sequence to the reference genome of Teleogryllus emma (GenBank EU557269.1) led to the identification of a numt sequence in the reference sequence. This unexpected result further highlights the need of a reliable and accessible strategy to eliminate this source of error. PMID:22606342

  14. Selection for increased mass-independent maximal metabolic rate suppresses innate but not adaptive immune function

    PubMed Central

    Downs, Cynthia J.; Brown, Jessi L.; Wone, Bernard; Donovan, Edward R.; Hunter, Kenneth; Hayes, Jack P.

    2013-01-01

    Both appropriate metabolic rates and sufficient immune function are essential for survival. Consequently, eco-immunologists have hypothesized that animals may experience trade-offs between metabolic rates and immune function. Previous work has focused on how basal metabolic rate (BMR) may trade-off with immune function, but maximal metabolic rate (MMR), the upper limit to aerobic activity, might also trade-off with immune function. We used mice artificially selected for high mass-independent MMR to test for trade-offs with immune function. We assessed (i) innate immune function by quantifying cytokine production in response to injection with lipopolysaccharide and (ii) adaptive immune function by measuring antibody production in response to injection with keyhole limpet haemocyanin. Selection for high mass-independent MMR suppressed innate immune function, but not adaptive immune function. However, analyses at the individual level also indicate a negative correlation between MMR and adaptive immune function. By contrast BMR did not affect immune function. Evolutionarily, natural selection may favour increasing MMR to enhance aerobic performance and endurance, but the benefits of high MMR may be offset by impaired immune function. This result could be important in understanding the selective factors acting on the evolution of metabolic rates. PMID:23303541

  15. The synthesis of magnetic lysozyme-imprinted polymers by means of distillation-precipitation polymerization for selective protein enrichment.

    PubMed

    Cao, Jiali; Zhang, Xihao; He, Xiwen; Chen, Langxing; Zhang, Yukui

    2014-02-01

    A protein imprinting approach for the synthesis of core-shell structure nanoparticles with a magnetic core and molecularly imprinted polymer (MIP) shell was developed using a simple distillation-precipitation polymerization method. In this work, Fe3O4 magnetic nanoparticles were first synthesized through a solvothermal method and then were conveniently surface-modified with 3-(methacryloyloxy)propyltrimethoxylsilane as anchor molecules to donate vinyl groups. Next a high-density MIP shell was coated onto the surface of the magnetic nanoparticles by the copolymerization of functional monomer acrylamide (AAm), cross-linking agent N,N'-methylenebisacrylamide (MBA), the initiator azodiisobutyronitrile (AIBN), and protein in acetonitrile heated at reflux. The morphology, adsorption, and recognition properties of the magnetic molecularly imprinted nanoparticles were investigated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), and rebinding experiments. The resulting MIP showed a high adsorption capacity (104.8 mg g(-1)) and specific recognition (imprinting factor=7.6) to lysozyme (Lyz). The as-prepared Fe3O4@Lyz-MIP nanoparticles with a mean diameter of 320 nm were coated with an MIP shell that was 20 nm thick, which enabled Fe3O4@Lyz-MIP to easily reach adsorption equilibrium. The high magnetization saturation (40.35 emu g(-1)) endows the materials with the convenience of magnetic separation under an external magnetic field and allows them to be subsequently reused. Furthermore, Fe3O4@Lyz-MIP could selectively extract a target protein from real egg-white samples under an external magnetic field. PMID:24203562

  16. The synthesis of magnetic lysozyme-imprinted polymers by means of distillation-precipitation polymerization for selective protein enrichment.

    PubMed

    Cao, Jiali; Zhang, Xihao; He, Xiwen; Chen, Langxing; Zhang, Yukui

    2014-02-01

    A protein imprinting approach for the synthesis of core-shell structure nanoparticles with a magnetic core and molecularly imprinted polymer (MIP) shell was developed using a simple distillation-precipitation polymerization method. In this work, Fe3O4 magnetic nanoparticles were first synthesized through a solvothermal method and then were conveniently surface-modified with 3-(methacryloyloxy)propyltrimethoxylsilane as anchor molecules to donate vinyl groups. Next a high-density MIP shell was coated onto the surface of the magnetic nanoparticles by the copolymerization of functional monomer acrylamide (AAm), cross-linking agent N,N'-methylenebisacrylamide (MBA), the initiator azodiisobutyronitrile (AIBN), and protein in acetonitrile heated at reflux. The morphology, adsorption, and recognition properties of the magnetic molecularly imprinted nanoparticles were investigated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), and rebinding experiments. The resulting MIP showed a high adsorption capacity (104.8 mg g(-1)) and specific recognition (imprinting factor=7.6) to lysozyme (Lyz). The as-prepared Fe3O4@Lyz-MIP nanoparticles with a mean diameter of 320 nm were coated with an MIP shell that was 20 nm thick, which enabled Fe3O4@Lyz-MIP to easily reach adsorption equilibrium. The high magnetization saturation (40.35 emu g(-1)) endows the materials with the convenience of magnetic separation under an external magnetic field and allows them to be subsequently reused. Furthermore, Fe3O4@Lyz-MIP could selectively extract a target protein from real egg-white samples under an external magnetic field.

  17. Novel Anti-Campylobacter Compounds Identified Using High Throughput Screening of a Pre-selected Enriched Small Molecules Library

    PubMed Central

    Kumar, Anand; Drozd, Mary; Pina-Mimbela, Ruby; Xu, Xiulan; Helmy, Yosra A.; Antwi, Janet; Fuchs, James R.; Nislow, Corey; Templeton, Jillian; Blackall, Patrick J.; Rajashekara, Gireesh

    2016-01-01

    Campylobacter is a leading cause of foodborne bacterial gastroenteritis worldwide and infections can be fatal. The emergence of antibiotic-resistant Campylobacter spp. necessitates the development of new antimicrobials. We identified novel anti-Campylobacter small molecule inhibitors using a high throughput growth inhibition assay. To expedite screening, we made use of a “bioactive” library of 4182 compounds that we have previously shown to be active against diverse microbes. Screening for growth inhibition of Campylobacter jejuni, identified 781 compounds that were either bactericidal or bacteriostatic at a concentration of 200 μM. Seventy nine of the bactericidal compounds were prioritized for secondary screening based on their physico-chemical properties. Based on the minimum inhibitory concentration against a diverse range of C. jejuni and a lack of effect on gut microbes, we selected 12 compounds. No resistance was observed to any of these 12 lead compounds when C. jejuni was cultured with lethal or sub-lethal concentrations suggesting that C. jejuni is less likely to develop resistance to these compounds. Top 12 compounds also possessed low cytotoxicity to human intestinal epithelial cells (Caco-2 cells) and no hemolytic activity against sheep red blood cells. Next, these 12 compounds were evaluated for ability to clear C. jejuni in vitro. A total of 10 compounds had an anti-C. jejuni effect in Caco-2 cells with some effective even at 25 μM concentrations. These novel 12 compounds belong to five established antimicrobial chemical classes; piperazines, aryl amines, piperidines, sulfonamide, and pyridazinone. Exploitation of analogs of these chemical classes may provide Campylobacter specific drugs that can be applied in both human and animal medicine. PMID:27092106

  18. Wavefront engineering: selective aperture illumination for increased depth of focus and super-resolution for photolithography

    NASA Astrophysics Data System (ADS)

    Kant, Rishi

    2015-08-01

    Photolithography has been and is the driving force behind enhancement and miniaturization of computers and their peripherals. Advances in photolithographic processes have enabled modern integrated circuits to have millions of electrical devices on a single, small circuit chip. Diffraction optics plays a central role in the photolithographic process, as during etching, the incoming light passes through a moderate-aperture focusing lens and converges on every point on the chip. Thus, the structure of the electromagnetic field in the focal region is of considerable interest. While techniques such as implantation and deposition processes control the vertical architecture of the integrated circuit chip, the lateral dimensions are defined solely by diffraction optics. The conventional imaging approach has a severe restriction because depth of focus shortens with an increase in resolution. Even though using shorter wavelength light such as deep ultraviolet is helpful, it too is reaching a point where further increase in resolution is necessary while, at the same time, preserving or increasing the depth of focus. Shortening of depth of focus with increase resolution is nonetheless the most severe limitation of photolithography. Thus, reduction in wavelength and increase in numerical aperture are viable options, but this approach has tremendous difficulties. In this study, we present a novel approach to achieve both super-resolution and increased depth of focus through a technique called selective aperture illumination (SAI). In SAI, the incoming light is redistributed by means of an optical element, phase, and attenuation masks. It is shown that both the increased depth focus and super-resolution are achieved by selectively choosing appropriate phase and amplitude at the entrance pupil.

  19. Chelating effect in short polymers for the design of bidentate binders of increased affinity and selectivity

    NASA Astrophysics Data System (ADS)

    Fortuna, Sara; Fogolari, Federico; Scoles, Giacinto

    2015-10-01

    The design of new strong and selective binders is a key step towards the development of new sensing devices and effective drugs. Both affinity and selectivity can be increased through chelation and here we theoretically explore the possibility of coupling two binders through a flexible linker. We prove the enhanced ability of double binders of keeping their target with a simple model where a polymer composed by hard spheres interacts with a spherical macromolecule, such as a protein, through two sticky spots. By Monte Carlo simulations and thermodynamic integration we show the chelating effect to hold for coupling polymers whose radius of gyration is comparable to size of the chelated particle. We show the binding free energy of flexible double binders to be higher than that of two single binders and to be maximized when the binding sites are at distances comparable to the mean free polymer end-to-end distance. The affinity of two coupled binders is therefore predicted to increase non linearly and in turn, by targeting two non-equivalent binding sites, this will lead to higher selectivity.

  20. Chelating effect in short polymers for the design of bidentate binders of increased affinity and selectivity

    PubMed Central

    Fortuna, Sara; Fogolari, Federico; Scoles, Giacinto

    2015-01-01

    The design of new strong and selective binders is a key step towards the development of new sensing devices and effective drugs. Both affinity and selectivity can be increased through chelation and here we theoretically explore the possibility of coupling two binders through a flexible linker. We prove the enhanced ability of double binders of keeping their target with a simple model where a polymer composed by hard spheres interacts with a spherical macromolecule, such as a protein, through two sticky spots. By Monte Carlo simulations and thermodynamic integration we show the chelating effect to hold for coupling polymers whose radius of gyration is comparable to size of the chelated particle. We show the binding free energy of flexible double binders to be higher than that of two single binders and to be maximized when the binding sites are at distances comparable to the mean free polymer end-to-end distance. The affinity of two coupled binders is therefore predicted to increase non linearly and in turn, by targeting two non-equivalent binding sites, this will lead to higher selectivity. PMID:26496975

  1. Development and characterization of a nanodendritic silver-based solid-phase extraction sorbent for selective enrichment of endocrine-disrupting chemicals in water and milk samples.

    PubMed

    Gao, Yuanji; Xia, Bing; Liu, Jie; Ji, Baocheng; Ma, Fengwei; Ding, Lisheng; Li, Bangjing; Zhou, Yan

    2015-11-01

    In this study, 4-[4-phenylazo-phenoxy] butyl-1-thiol (AzSH) functionalized nanodendritic silver (AzS@AgNDs) materials were prepared as a solid-phase extraction (SPE) sorbent for the selective extraction of estrogens. AzS@AgNDs possess an extremely large surface-to-volume ratio and a small average particle size. The performance of the material was evaluated by selective enrichment of hexestrol, diethylstilbestrol, dienestrol and bisphenol A in water and milk samples followed by rapid ultra-performance liquid chromatography-electrospray ionization mass spectrometry (UPLC-ESI-MS) analyses. The results exhibited that AzS@AgNDs had excellent adsorption capability for the targeted estrogens. The limits of detection of the four estrogens ranged from 0.1 to 5.0 pg/mL. The recoveries of the estrogens spiked into tap water were over the range of 83.6-105.3% with relative standard deviations of 2.8-6.0%. The results indicated the capability of this method for the rapid determination of estrogens in milk and other environmental water samples. In addition, this method would be useful for the determination of human exposure and health risk assessments trace level of endocrine-disrupting compounds (EDCs) in drinking water.

  2. Development and characterization of a nanodendritic silver-based solid-phase extraction sorbent for selective enrichment of endocrine-disrupting chemicals in water and milk samples.

    PubMed

    Gao, Yuanji; Xia, Bing; Liu, Jie; Ji, Baocheng; Ma, Fengwei; Ding, Lisheng; Li, Bangjing; Zhou, Yan

    2015-11-01

    In this study, 4-[4-phenylazo-phenoxy] butyl-1-thiol (AzSH) functionalized nanodendritic silver (AzS@AgNDs) materials were prepared as a solid-phase extraction (SPE) sorbent for the selective extraction of estrogens. AzS@AgNDs possess an extremely large surface-to-volume ratio and a small average particle size. The performance of the material was evaluated by selective enrichment of hexestrol, diethylstilbestrol, dienestrol and bisphenol A in water and milk samples followed by rapid ultra-performance liquid chromatography-electrospray ionization mass spectrometry (UPLC-ESI-MS) analyses. The results exhibited that AzS@AgNDs had excellent adsorption capability for the targeted estrogens. The limits of detection of the four estrogens ranged from 0.1 to 5.0 pg/mL. The recoveries of the estrogens spiked into tap water were over the range of 83.6-105.3% with relative standard deviations of 2.8-6.0%. The results indicated the capability of this method for the rapid determination of estrogens in milk and other environmental water samples. In addition, this method would be useful for the determination of human exposure and health risk assessments trace level of endocrine-disrupting compounds (EDCs) in drinking water. PMID:26572841

  3. Down-regulation of BDNF in cell and animal models increases striatal-enriched protein tyrosine phosphatase 61 (STEP61 ) levels.

    PubMed

    Xu, Jian; Kurup, Pradeep; Azkona, Garikoitz; Baguley, Tyler D; Saavedra, Ana; Nairn, Angus C; Ellman, Jonathan A; Pérez-Navarro, Esther; Lombroso, Paul J

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) regulates synaptic strengthening and memory consolidation, and altered BDNF expression is implicated in a number of neuropsychiatric and neurodegenerative disorders. BDNF potentiates N-methyl-D-aspartate receptor function through activation of Fyn and ERK1/2. STriatal-Enriched protein tyrosine Phosphatase (STEP) is also implicated in many of the same disorders as BDNF but, in contrast to BDNF, STEP opposes the development of synaptic strengthening. STEP-mediated dephosphorylation of the NMDA receptor subunit GluN2B promotes internalization of GluN2B-containing NMDA receptors, while dephosphorylation of the kinases Fyn, Pyk2, and ERK1/2 leads to their inactivation. Thus, STEP and BDNF have opposing functions. In this study, we demonstrate that manipulation of BDNF expression has a reciprocal effect on STEP61 levels. Reduced BDNF signaling leads to elevation of STEP61 both in BDNF(+/-) mice and after acute BDNF knockdown in cortical cultures. Moreover, a newly identified STEP inhibitor reverses the biochemical and motor abnormalities in BDNF(+/-) mice. In contrast, increased BDNF signaling upon treatment with a tropomyosin receptor kinase B agonist results in degradation of STEP61 and a subsequent increase in the tyrosine phosphorylation of STEP substrates in cultured neurons and in mouse frontal cortex. These findings indicate that BDNF-tropomyosin receptor kinase B signaling leads to degradation of STEP61 , while decreased BDNF expression results in increased STEP61 activity. A better understanding of the opposing interaction between STEP and BDNF in normal cognitive functions and in neuropsychiatric disorders will hopefully lead to better therapeutic strategies. Altered expression of BDNF and STEP61 has been implicated in several neurological disorders. BDNF and STEP61 are known to regulate synaptic strengthening, but in opposite directions. Here, we report that reduced BDNF signaling leads to elevation of STEP61 both in

  4. Photocatalytic degradation-excitation-emission matrix fluorescence for increasing the selectivity of polycyclic aromatic hydrocarbon analyses.

    PubMed

    Kim, Yoon-Chang; Jordan, James A; Nahorniak, Michelle L; Booksh, Karl S

    2005-12-01

    The application of photocatalysis enhancement to calibration of fluorescence excitation-emission matrixes (EEMs) with parallel factor (PARAFAC) analysis is described. In this study, three- and four-way PARAFAC analysis was employed to extract the fluorescent species' spectra from overlapping EEMs. Time-dependent photocatalysis degradation of the polycyclic aromatic hydrocarbons (PAHs) was employed to create an additional dimension for analysis. The consequent four-dimension degradation-EEM data cubes have greater selectivity for each PAH than do three-dimension EEM data cubes alone. On a scale of 0 to 1, with 0 being completely collinear spectra and 1 being orthogonal spectra, including the time-dependent measurements increased the selectivity an average of 21%, from 0.73 to 0.87.

  5. Sulindac sulfide selectively increases sensitivity of ABCC1 expressing tumor cells to doxorubicin and glutathione depletion

    PubMed Central

    Whitt, Jason D.; Keeton, Adam B.; Gary, Bernard D.; Sklar, Larry A.; Sodani, Kamlesh; Chen, Zhe-Sheng; Piazza, Gary A.

    2016-01-01

    Abstract ATP-binding cassette (ABC) transpo rters ABCC1 (MRP1), ABCB1 (P-gp), and ABCG2 (BCRP) contribute to chemotherapy failure. The primary goals of this study were to characterize the efficacy and mechanism of the non­steroidal anti-inflammatory drug (NSAID), sulindac sulfide, to reverse ABCC1 mediated resistance to chemother­apeutic drugs and to determine if sulindac sulfide can influence sensitivity to chemotherapeutic drugs independently of drug efflux. Cytotoxicity assays were performed to measure resistance of ABC-expressing cell lines to doxoru­bicin and other chemotherapeutic drugs. NSAIDs were tested for the ability to restore sensitivity to resistance selected tumor cell lines, as well as a large panel of standard tumor cell lines. Other experiments characterized the mechanism by which sulindac sulfide inhibits ABCC1 substrate and co-substrate (GSH) transport in isolated membrane vesicles and intact cells. Selective reversal of multi-drug resistance (MDR), decreased efflux of doxor­ubicin, and fluorescent substrates were demonstrated by sulindac sulfide and a related NSAID, indomethacin, in resistance selected and engineered cell lines expressing ABCC1, but not ABCB1 or ABCG2. Sulindac sulfide also inhibited transport of leukotriene C4 into membrane vesicles. Sulindac sulfide enhanced the sensitivity to doxoru­bicin in 24 of 47 tumor cell lines, including all melanoma lines tested (7-7). Sulindac sulfide also decreased intra­cellular GSH in ABCC1 expressing cells, while the glutathione synthesis inhibitor, BSO, selectively increased sensitivity to sulindac sulfide induced cytotoxicity. Sulindac sulfide potently and selectively reverses ABCC1-mediated MDR at clinically achievable concentrations. ABCC1 expressing tumors may be highly sensitive to the direct cytotoxicity of sulindac sulfide, and in combination with chemotherapeutic drugs that induce oxidative stress.

  6. Fabrication of boronate-decorated polyhedral oligomeric silsesquioxanes grafted cotton fiber for the selective enrichment of nucleosides in urine.

    PubMed

    Gao, Li; Wei, Yinmao

    2016-06-01

    Various cotton fiber based boronate-affinity adsorbents are recently developed for the sample pretreatment of cis-diol-containing biomolecules, but most do not have efficient capacity due to limited binding sites on the surface of cotton fibers. To increase the density of boronate groups on the surface of cotton fiber, polyhedral oligomeric silsesquioxanes were used to modify cotton fiber to provide plentiful reactive sites for subsequent functionalization with 4-formylphenylboronic acid. The new adsorbent showed special recognition ability towards cis-diols and high adsorption capacity (175 μg/g for catechol, 250 μg/g for dopamine, 400 μg/g for adenosine). The in-pipette-tip solid-phase extraction was investigated under different conditions, including pH and ionic strength of solution, adsorbent amount, pipette times, washing solvent, and elution solvent. The in-pipette-tip solid-phase extraction coupled with high-performance liquid chromatography was used to analyze four nucleosides in urine samples. Under the optimal extraction conditions, the detection limits were determined to be between 5.1 and 6.1 ng/mL (S/N  =  3), and the linearity ranged from 20 to 500 ng/mL for these analytes. The accuracy of the analytical method was examined by studying the relative recoveries of analytes in real urine samples with recoveries varying from 83 to 104% (RSD = 3.9-10.2%, n = 3). PMID:27138862

  7. Economic Analysis. Enrichment.

    ERIC Educational Resources Information Center

    Sterling Inst., Washington, DC. Educational Technology Center.

    A multimedia course in economic analysis was prepared for the United States Naval Academy. (ED 043 790 and ED 043 791 are the final reports of the project evaluation and development model.) This report presents enrichment segments for selected core segments in concept areas one and two, covering a spectrum of economic systems, the influence of…

  8. Highly selective enrichment of baicalin in rat plasma by boronic acid-functionalized core-shell magnetic microspheres: Validation and application to a pharmacokinetic study.

    PubMed

    Huang, Taomin; Xiong, Ya; Chen, Nianzu; Wang, Donglei; Lai, Yonghua; Deng, Chunhui

    2016-01-15

    To the best of our knowledge, this study is the first to successfully apply a novel, highly selective enrichment technique based on boronic acid-functionalized core-shell magnetic microspheres (BA-Fe3O4@SiO2-Au@mSiO2) with a large surface area and uniform pore size, to determine the baicalin concentration in rat plasma by HPLC. By taking advantage of the special interaction between boronic acid and baicalin under alkaline conditions, as well as the microspheres' size exclusion ability, baicalin was selectively extracted from protein-rich biosamples, such as plasma, without any other pretreatment procedure except for a 10-min vortexing step. BA-Fe3O4@SiO2-Au@mSiO2 microsphere-adsorbed baicalin was straightforwardly and rapidly isolated from the matrix using a magnet. Baicalin was subsequently eluted from the microspheres under acidic conditions for 2min for further HPLC analysis. The extraction conditions, such as the amount of microspheres added, adsorption time, adsorption pH, and elution time and pH, were also determined. Furthermore, method validation, including the linear range, detection limit, precision, accuracy, and recovery, were determined. This newly developed method based on BA-Fe3O4@SiO2-Au@mSiO2 microspheres is a simple, accurate, selective, and green analytical preparatory technique for analyzing baicalin in rat plasma. This study will be further novel research on the analysis of complex plasma samples and the pharmacokinetics of drugs similar to baicalin.

  9. Resource competition induces heterogeneity and can increase cohort survivorship: selection-event duration matters.

    PubMed

    Gosselin, Jennifer L; Anderson, James J

    2013-12-01

    Determining when resource competition increases survivorship can reveal processes underlying population dynamics and reinforce the importance of heterogeneity among individuals in conservation. We ran an experiment mimicking the effects of competition in a growing season on survivorship during a selection event (e.g., overwinter starvation, drought). Using a model fish species (Poecilia reticulata), we studied how food availability and competition affect mass in a treatment stage, and subsequently survivorship in a challenge stage of increased temperature and starvation. The post-treatment mean mass was strongly related to the mean time to mortality and mass at mortality at all levels of competition. However, competition increased variance in mass and extended the right tail of the survivorship curve, resulting in a greater number of individuals alive beyond a critical temporal threshold ([Formula: see text]) than without competition. To realize the benefits from previously experienced competition, the duration of the challenge ([Formula: see text]) following the competition must exceed the critical threshold [Formula: see text] (i.e., competition increases survivorship when [Formula: see text]). Furthermore, this benefit was equivalent to increasing food availability by 20 % in a group without competition in our experiment. The relationship of [Formula: see text] to treatment and challenge conditions was modeled by characterizing mortality through mass loss in terms of the stochastic rate of loss of vitality (individual's survival capacity). In essence, when the duration of a selection event exceeds [Formula: see text], competition-induced heterogeneity buffers against mortality through overcompensation processes among individuals of a cohort. Overall, our study demonstrates an approach to quantify how early life stage heterogeneity affects survivorship. PMID:23912261

  10. Acidic Residues in the Hfq Chaperone Increase the Selectivity of sRNA Binding and Annealing.

    PubMed

    Panja, Subrata; Santiago-Frangos, Andrew; Schu, Daniel J; Gottesman, Susan; Woodson, Sarah A

    2015-11-01

    Hfq facilitates gene regulation by small non-coding RNAs (sRNAs), thereby affecting bacterial attributes such as biofilm formation and virulence. Escherichia coli Hfq recognizes specific U-rich and AAN motifs in sRNAs and target mRNAs, after which an arginine patch on the rim promotes base pairing between their complementary sequences. In the cell, Hfq must discriminate between many similar RNAs. Here, we report that acidic amino acids lining the sRNA binding channel between the inner pore and rim of the Hfq hexamer contribute to the selectivity of Hfq's chaperone activity. RNase footprinting, in vitro binding and stopped-flow fluorescence annealing assays showed that alanine substitution of D9, E18 or E37 strengthened RNA interactions with the rim of Hfq and increased annealing of non-specific or U-tailed RNA oligomers. Although the mutants were less able than wild-type Hfq to anneal sRNAs with wild-type rpoS mRNA, the D9A mutation bypassed recruitment of Hfq to an (AAN)4 motif in rpoS, both in vitro and in vivo. These results suggest that acidic residues normally modulate access of RNAs to the arginine patch. We propose that this selectivity limits indiscriminate target selection by E. coli Hfq and enforces binding modes that favor genuine sRNA and mRNA pairs.

  11. Serum factor induces selective increase in Na-channel expression in cultured skeletal muscle

    SciTech Connect

    Brodie, C.; Sampson, S.R. )

    1991-07-01

    The authors have examined effects of horse serum (HS) and various fractions (1 million-1M, 300K, 100K, and 30K nominal molecular weight limit) obtained by ultrafiltration on expression of TTX-sensitive Na-channels and on activities of the Na-K pump and glucose transport systems in cultured myotubes obtained from 1-2-day-old neonatal rat pups. Five-day-old cells were transferred to serum-free medium with no hormone or growth factor supplements (DMEM) for 24 hr and then treated with the various serum fractions for 48 hr. Measurements were made of specific (3H)-saxitoxin (STX) binding, action potential properties, 86Rb-uptake and 2-deoxyglucose (2-DG) uptake. HS significantly increased all parameters compared to DMEM (increases in STX-binding, 69%; Rb-uptake, 65%; 2-DG uptake, 93%). Results of treatment with the separate fractions showed that the 300K fraction caused a significantly greater increase in STX-binding than either HS or the other fractions. In contrast, the increases in Rb and 2-DG uptakes induced by the different fractions were not different from that obtained with HS. They conclude that serum contains a factor that selectively increases expression of TTX-sensitive Na-channels in skeletal muscle.

  12. Selective increase in lymphocyte interferon response to vaccinia antigen after revaccination.

    PubMed

    Epstein, L B; Stevens, D A; Merigan, T C

    1972-09-01

    Viral antigen prepared by heat inactivation of vaccinia virus stimulated production of interferon in association with transformation of sensitized human lymphocytes in vitro. Involvement of a macrophage-lymphocyte interaction in production of interferon stimulated by viral antigen was found in which macrophage greatly augmented the amount of interferon produced by lymphocytes. Reimmunization with live vaccinia virus resulted in a selective increase in the ability of lymphocytes to produce interferon in the presence of viral antigen 4-7 weeks later without a corresponding increase in the degree of already significant lymphocyte transformation. There was no correlation between the extent of lymphocyte transformation and the amount of interferon produced. The augmented interferon response after reimmunization described in this study may be a significant component of the protective effect of immunization with vaccinia against disease occurring after exposure to small-pox.

  13. A CB2-Selective Cannabinoid Suppresses T-cell Activities and Increases Tregs and IL-10

    PubMed Central

    Robinson, Rebecca H.; Meissler, Joseph J.; Fan, Xiaoxuan; Yu, Daohai; Adler, Martin W.; Eisenstein, Toby K.

    2015-01-01

    We have previously shown that agonists selective for the cannabinoid receptor 2 (CB2), including O-1966, inhibit the Mixed Lymphocyte Reaction (MLR), an in vitro correlate of organ graft rejection, predominantly through effects on T-cells. Current studies explored the mechanism of this immunosuppression by O-1966 using mouse spleen cells. Treatment with O-1966 dose-relatedly decreased levels of the active nuclear forms of the transcription factors NF-κB and NFAT in wild-type T-cells, but not T-cells from CB2 knockout (CB2R k/o) mice. Additionally, a gene expression profile of purified T-cells from MLR cultures generated using a PCR T-cell activation array showed that O-1966 decreased mRNA expression of CD40 ligand and CyclinD3, and increased mRNA expression of Src-like-adaptor 2 (SLA2), Suppressor of Cytokine Signaling 5 (SOCS5), and IL-10. The increase in IL-10 was confirmed by measuring IL-10 protein levels in MLR culture supernatants. Further, an increase in the percentage of regulatory T-cells (Tregs) was observed in MLR cultures. Pretreatment with anti-IL-10 resulted in a partial reversal of the inhibition of proliferation and blocked the increase of Tregs. Additionally, O-1966 treatment caused a dose-related decrease in the expression of CD4 in MLR cultures from wild-type, but not CB2R k/o, mice. These data support the potential of CB2-selective agonists as useful therapeutic agents to prolong graft survival in transplant patients, and strengthens their potential as a new class of immunosuppressive agents with broader applicability. PMID:25980325

  14. Selection for tameness, a key behavioral trait of domestication, increases adult hippocampal neurogenesis in foxes.

    PubMed

    Huang, Shihhui; Slomianka, Lutz; Farmer, Andrew J; Kharlamova, Anastasiya V; Gulevich, Rimma G; Herbeck, Yury E; Trut, Lyudmila N; Wolfer, David P; Amrein, Irmgard

    2015-08-01

    Work on laboratory and wild rodents suggests that domestication may impact on the extent of adult hippocampal neurogenesis and its responsiveness to regulatory factors. There is, however, no model of laboratory rodents and their nondomesticated conspecifics that would allow a controlled comparison of the effect of domestication. Here, we present a controlled within-species comparison of adult hippocampal neurogenesis in farm-bred foxes (Vulpes vulpes) that differ in their genetically determined degree of tameness. Quantitative comparisons of cell proliferation (Ki67) and differentiating cells of neuronal lineage (doublecortin, DCX) in the hippocampus of foxes were performed as a proxy for neurogenesis. Higher neurogenesis was observed in tameness-selected foxes, notably in an extended subgranular zone of the middle and temporal compartments of the hippocampus. Increased neurogenesis is negatively associated with aggressive behavior. Across all animals, strong septotemporal gradients were found, with higher numbers of proliferating cells and young neurons relative to resident granule cells in the temporal than in the septal hippocampus. The opposite gradient was found for the ratio of DCX/Ki67- positive cells. When tameness-selected and unselected foxes are compared with rodents and primates, proliferation is similar, while the number of young neurons is higher. The difference may be mediated by an extended period of differentiation or higher rate of survival. On the background of this species-specific neurogenic pattern, selection of foxes for a single behavioral trait key to domestication, i.e., genetic tameness, is accompanied by global and region-specific increases in neurogenesis.

  15. Intensive aquaculture selects for increased virulence and interference competition in bacteria.

    PubMed

    Sundberg, Lotta-Riina; Ketola, Tarmo; Laanto, Elina; Kinnula, Hanna; Bamford, Jaana K H; Penttinen, Reetta; Mappes, Johanna

    2016-03-16

    Although increased disease severity driven by intensive farming practices is problematic in food production, the role of evolutionary change in disease is not well understood in these environments. Experiments on parasite evolution are traditionally conducted using laboratory models, often unrelated to economically important systems. We compared how the virulence, growth and competitive ability of a globally important fish pathogen, Flavobacterium columnare, change under intensive aquaculture. We characterized bacterial isolates from disease outbreaks at fish farms during 2003-2010, and compared F. columnare populations in inlet water and outlet water of a fish farm during the 2010 outbreak. Our data suggest that the farming environment may select for bacterial strains that have high virulence at both long and short time scales, and it seems that these strains have also evolved increased ability for interference competition. Our results are consistent with the suggestion that selection pressures at fish farms can cause rapid changes in pathogen populations, which are likely to have long-lasting evolutionary effects on pathogen virulence. A better understanding of these evolutionary effects will be vital in prevention and control of disease outbreaks to secure food production.

  16. Selective Estrogen Receptor Modulation Increases Hippocampal Activity during Probabilistic Association Learning in Schizophrenia.

    PubMed

    Kindler, Jochen; Weickert, Cynthia Shannon; Skilleter, Ashley J; Catts, Stanley V; Lenroot, Rhoshel; Weickert, Thomas W

    2015-09-01

    People with schizophrenia show probabilistic association learning impairment in conjunction with abnormal neural activity. The selective estrogen receptor modulator (SERM) raloxifene preserves neural activity during memory in healthy older men and improves memory in schizophrenia. Here, we tested the extent to which raloxifene modifies neural activity during learning in schizophrenia. Nineteen people with schizophrenia participated in a twelve-week randomized, double-blind, placebo-controlled, cross-over adjunctive treatment trial of the SERM raloxifene administered orally at 120 mg daily to assess brain activity during probabilistic association learning using functional magnetic resonance imaging (fMRI). Raloxifene improved probabilistic association learning and significantly increased fMRI BOLD activity in the hippocampus and parahippocampal gyrus relative to placebo. A separate region of interest confirmatory analysis in 21 patients vs 36 healthy controls showed a positive association between parahippocampal neural activity and learning in patients, but no such relationship in the parahippocampal gyrus of healthy controls. Thus, selective estrogen receptor modulation by raloxifene concurrently increases activity in the parahippocampal gyrus and improves probabilistic association learning in schizophrenia. These results support a role for estrogen receptor modulation of mesial temporal lobe neural activity in the remediation of learning disabilities in both men and women with schizophrenia.

  17. Intensive aquaculture selects for increased virulence and interference competition in bacteria.

    PubMed

    Sundberg, Lotta-Riina; Ketola, Tarmo; Laanto, Elina; Kinnula, Hanna; Bamford, Jaana K H; Penttinen, Reetta; Mappes, Johanna

    2016-03-16

    Although increased disease severity driven by intensive farming practices is problematic in food production, the role of evolutionary change in disease is not well understood in these environments. Experiments on parasite evolution are traditionally conducted using laboratory models, often unrelated to economically important systems. We compared how the virulence, growth and competitive ability of a globally important fish pathogen, Flavobacterium columnare, change under intensive aquaculture. We characterized bacterial isolates from disease outbreaks at fish farms during 2003-2010, and compared F. columnare populations in inlet water and outlet water of a fish farm during the 2010 outbreak. Our data suggest that the farming environment may select for bacterial strains that have high virulence at both long and short time scales, and it seems that these strains have also evolved increased ability for interference competition. Our results are consistent with the suggestion that selection pressures at fish farms can cause rapid changes in pathogen populations, which are likely to have long-lasting evolutionary effects on pathogen virulence. A better understanding of these evolutionary effects will be vital in prevention and control of disease outbreaks to secure food production. PMID:26936249

  18. Enrichment of DNRA bacteria in a continuous culture

    PubMed Central

    van den Berg, Eveline M; van Dongen, Udo; Abbas, Ben; van Loosdrecht, Mark CM

    2015-01-01

    Denitrification and dissimilatory nitrate reduction to ammonium (DNRA) are competing microbial nitrate-reduction processes. The occurrence of DNRA has been shown to be effected qualitatively by various parameters in the environment. A more quantitative understanding can be obtained using enrichment cultures in a laboratory reactor, yet no successful DNRA enrichment culture has been described. We showed that a stable DNRA-dominated enrichment culture can be obtained in a chemostat system. The enrichment was based on the hypothesis that nitrate limitation is the dominant factor in selecting for DNRA. First, a conventional denitrifying culture was enriched from activated sludge, with acetate and nitrate as substrates. Next, the acetate concentration in the medium was increased to obtain nitrate-limiting conditions. As a result, conversions shifted from denitrification to DNRA. In this selection of a DNRA culture, two important factors were the nitrate limitation and a relatively low dilution rate (0.026 h−1). The culture was a highly enriched population of Deltaproteobacteria most closely related to Geobacter lovleyi, based on 16S rRNA gene sequencing (97% similarity). We established a stable and reproducible cultivation method for the enrichment of DNRA bacteria in a continuously operated reactor system. This enrichment method allows to further investigate the DNRA process and address the factors for competition between DNRA and denitrification, or other N-conversion pathways. PMID:25909972

  19. Preparation of sandwich-structured graphene/mesoporous silica composites with C8-modified pore wall for highly efficient selective enrichment of endogenous peptides for mass spectrometry analysis.

    PubMed

    Yin, Peng; Wang, Yuhua; Li, Yan; Deng, Chunhui; Zhang, Xiangmin; Yang, Pengyuan

    2012-09-01

    In this study, sandwich-structured graphene/mesoporous silica composites (C8-modified graphene@mSiO(2)) were synthesized by coating mesoporous silica onto hydrophilic graphene nanosheets through a surfactant-mediated cocondensation sol-gel process. The newly prepared C8-modified graphene@mSiO(2) nanocomposites possess unique properties of extended plate-like morphology, good water dispersibility, highly open pore structure, uniform pore size (2.8 nm), high surface area (632 m(2)/g), and C8-modified-interior pore walls. The unique structure of the C8-modified graphene@mSiO(2) composite nanosheets not only provide extended planes with hydrophilic surface that prevents aggregation in solution, but also offer a huge number of C8-modified mesopores with high surface area that can ensure an efficient adsorption of peptides through hydrophobic-hydrophobic interaction between C8-moified pore walls and target molecules. The obtained C8-modified graphene@mSiO(2) materials were utilized for size selectively and specifically enriching peptides in standard peptide mixtures and endogenous peptides in real biological samples (mouse brain tissue). PMID:22837154

  20. Designed synthesis of Graphene @titania @mesoporous silica hybrid material as size-exclusive metal oxide affinity chromatography platform for selective enrichment of endogenous phosphopeptides.

    PubMed

    Yao, Jizong; Sun, Nianrong; Deng, Chunhui; Zhang, Xiangming

    2016-04-01

    In this work, a novel size-exclusive metal oxide affinity chromatography (SE-MOAC) platform was built for phosphoproteome research. The operation for preparing graphene @titania @mesoporous silica nanohybrids (denoted as G@TiO2@mSiO2) was facile and easy to conduct by grafting titania nanoparticles on polydopamine (PD)-covered graphene, following a layer of mesoporous silica was coated on the outermost layer. The G@TiO2@mSiO2 nanohybrids exhibited high sensitivity with a low detection limit of 5 amol/μL (a total amount of 1 fmol) and high selectivity for phosphopeptides at a mass ratio of phosphopeptides to non-phosphopeptides (1:1000). The size-exclusive capability of the nanohybrids were also demonstrated by enriching the phosphopeptides from the mixture of Bovine Serum Albumin (BSA), α-casein, and β-casein digests with a high mass ratio (β-casein digests: α-casein: BSA, 1:500:500), which was attributed to the large surface area and ordered mesoporous channels. In addition, the G@TiO2@mSiO2 nanohybrids were employed to capture the endogenous phosphopeptides from human serum successfully. PMID:26838411

  1. Exercise Increases Markers of Spermatogenesis in Rats Selectively Bred for Low Running Capacity

    PubMed Central

    Torma, Ferenc; Koltai, Erika; Nagy, Enikő; Ziaaldini, Mohammad Mosaferi; Posa, Aniko; Koch, Lauren G.; Britton, Steven L.; Boldogh, Istvan; Radak, Zsolt

    2014-01-01

    The oxidative stress effect of exercise training on testis function is under debate. In the present study we used a unique rat model system developed by artificial selection for low and high intrinsic running capacity (LCR and HCR, respectively) to evaluate the effects of exercise training on apoptosis and spermatogenesis in testis. Twenty-four 13-month-old male rats were assigned to four groups: control LCR (LCR-C), trained LCR (LCR-T), control HCR (HCR-C), and trained HCR (HCR-T). Ten key proteins connecting aerobic exercise capacity and general testes function were assessed, including those that are vital for mitochondrial biogenesis. The VO2 max of LCR-C group was about 30% lower than that of HCR-C rats, and the SIRT1 levels were also significantly lower than HCR-C. Twelve weeks of training significantly increased maximal oxygen consumption in LCR by nearly 40% whereas HCR remained unchanged. LCR-T had significantly higher levels of peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1α), decreased levels of reactive oxygen species and increased acetylated p53 compared to LCR-C, while training produced no significant changes for these measures in HCR rats. BAX and Blc-2 were not different among all four groups. The levels of outer dense fibers -1 (Odf-1), a marker of spermatogenesis, increased in LCR-T rats, but decreased in HCR-TR rats. Moreover, exercise training increased the levels of lactate dehydrogenase C (LDHC) only in LCR rats. These data suggest that rats with low inborn exercise capacity can increase whole body oxygen consumption and running exercise capacity with endurance training and, in turn, increase spermatogenesis function via reduction in ROS and heightened activity of p53 in testes. PMID:25493948

  2. Combinatorial engineering to enhance amylosucrase performance: construction, selection, and screening of variant libraries for increased activity.

    PubMed

    van der Veen, Bart A; Potocki-Véronèse, Gabrielle; Albenne, Cécile; Joucla, Gilles; Monsan, Pierre; Remaud-Simeon, Magali

    2004-02-27

    Amylosucrase is a glucosyltransferase belonging to family 13 of glycoside hydrolases and catalyses the formation of an amylose-type polymer from sucrose. Its potential use as an industrial tool for the synthesis or the modification of polysaccharides, however, is limited by its low catalytic efficiency on sucrose alone, its low stability, and its side reactions resulting in sucrose isomer formation. Therefore, combinatorial engineering of the enzyme through random mutagenesis, gene shuffling, and selective screening (directed evolution) was started, in order to generate more efficient variants of the enzyme. A convenient zero background expression cloning strategy was developed. Mutant gene libraries were generated by error-prone polymerase chain reaction (PCR), using Taq polymerase with unbalanced dNTPs or Mutazyme trade mark, followed by recombination of the PCR products by DNA shuffling. A selection method was developed to allow only the growth of amylosucrase active clones on solid mineral medium containing sucrose as the sole carbon source. Automated protocols were designed to screen amylosucrase activity from mini-cultures using dinitrosalicylic acid staining of reducing sugars and iodine staining of amylose-like polymer. A pilot experiment using the described mutagenesis, selection, and screening methods yielded two variants with significantly increased activity (five-fold under the screening conditions). Sequence analysis of these variants revealed mutations in amino acid residues which would not be considered for rational design of improved amylosucrase variants. A method for the characterisation of amylosucrase action on sucrose, consisting of accurate measurement of glucose and fructose concentrations, was introduced. This allows discrimination between hydrolysis and transglucosylation, enabling a more detailed comparison between wild-type and mutant enzymes.

  3. Selective Pharmacologic Inhibition of a PASTA Kinase Increases Listeria monocytogenes Susceptibility to β-Lactam Antibiotics

    PubMed Central

    Pensinger, Daniel A.; Aliota, Matthew T.; Schaenzer, Adam J.; Boldon, Kyle M.; Ansari, Israr-ul H.; Vincent, William J. B.; Knight, Benjamin; Reniere, Michelle L.; Striker, Rob

    2014-01-01

    While β-lactam antibiotics are a critical part of the antimicrobial arsenal, they are frequently compromised by various resistance mechanisms, including changes in penicillin binding proteins of the bacterial cell wall. Genetic deletion of the penicillin binding protein and serine/threonine kinase-associated protein (PASTA) kinase in methicillin-resistant Staphylococcus aureus (MRSA) has been shown to restore β-lactam susceptibility. However, the mechanism remains unclear, and whether pharmacologic inhibition would have the same effect is unknown. In this study, we found that deletion or pharmacologic inhibition of the PASTA kinase in Listeria monocytogenes by the nonselective kinase inhibitor staurosporine results in enhanced susceptibility to both aminopenicillin and cephalosporin antibiotics. Resistance to vancomycin, another class of cell wall synthesis inhibitors, or antibiotics that inhibit protein synthesis was unaffected by staurosporine treatment. Phosphorylation assays with purified kinases revealed that staurosporine selectively inhibited the PASTA kinase of L. monocytogenes (PrkA). Importantly, staurosporine did not inhibit a L. monocytogenes kinase without a PASTA domain (Lmo0618) or the PASTA kinase from MRSA (Stk1). Finally, inhibition of PrkA with a more selective kinase inhibitor, AZD5438, similarly led to sensitization of L. monocytogenes to β-lactam antibiotics. Overall, these results suggest that pharmacologic targeting of PASTA kinases can increase the efficacy of β-lactam antibiotics. PMID:24867981

  4. Tumor-selective peptide-carrier delivery of Paclitaxel increases in vivo activity of the drug

    PubMed Central

    Brunetti, Jlenia; Pillozzi, Serena; Falciani, Chiara; Depau, Lorenzo; Tenori, Eleonora; Scali, Silvia; Lozzi, Luisa; Pini, Alessandro; Arcangeli, Annarosa; Menichetti, Stefano; Bracci, Luisa

    2015-01-01

    Taxanes are highly effective chemotherapeutic drugs against proliferating cancer and an established option in the standard treatment of ovarian and breast cancer. However, treatment with paclitaxel is associated with severe side effects, including sensory axonal neuropathy, and its poor solubility in water complicates its formulation. In this paper we report the in vitro and in vivo activity of a new form of paclitaxel, modified for conjugation with a tumor-selective tetrabranched peptide carrier (NT4). NT4 selectively targets tumor cells by binding to membrane sulfated glycosaminoglycans (GAG) and to endocytic receptors, like LRP1 and LRP6, which are established tumor markers. Biological activity of NT4-paclitaxel was tested in vitro on MDA-MB 231 and SKOV-3 cell lines, representing breast and ovarian cancer, respectively, and in vivo in an orthotopic mouse model of human breast cancer. Using in vivo bioluminescence imaging, we found that conjugation of paclitaxel with the NT4 peptide led to increased therapeutic activity of the drug in vivo. NT4-paclitaxel induced tumor regression, whereas treatment with unconjugated paclitaxel only produced a reduction in tumor growth. Moreover, unlike paclitaxel, NT4-paclitaxel is very hydrophilic, which may improve its pharmacokinetic profile and allow the use of less toxic dilution buffers, further decreasing its general chemotherapic toxicity. PMID:26626158

  5. Combinatorial approaches with selected phytochemicals to increase antibiotic efficacy against Staphylococcus aureus biofilms.

    PubMed

    Abreu, Ana Cristina; Saavedra, Maria José; Simões, Lúcia C; Simões, Manuel

    2016-10-01

    Combinations of selected phytochemicals (reserpine, pyrrolidine, quinine, morin and quercetin) with antibiotics (ciprofloxacin, tetracycline and erythromycin) were tested on the prevention and control of Staphylococcus aureus biofilms. The phytochemicals were also studied for their ability to avoid antibiotic adaptation and to inhibit antibiotic efflux pumps. Morin, pyrrolidine and quercetin at subinhibitory concentrations had significant effects in biofilm prevention and/or control when applied alone and combined with antibiotics. Synergism between antibiotics and phytochemicals was found especially against biofilms of NorA overexpressing strain S. aureus SA1199B. This strain when growing with subinhibitory concentrations of ciprofloxacin developed increased tolerance to this antibiotic. However, this was successfully reversed by quinine and morin. In addition, reserpine and quercetin showed significant efflux pump inhibition. The overall results demonstrate the role of phytochemicals in co-therapies to promote more efficient treatments and decrease antimicrobial resistance to antibiotics, with substantial effects against S. aureus in both planktonic and biofilm states.

  6. Tipping the mutation-selection balance: Limited migration increases the frequency of deleterious mutants.

    PubMed

    Cooper, Jacob D; Neuhauser, Claudia; Dean, Antony M; Kerr, Benjamin

    2015-09-01

    Typical mutation-selection models assume well-mixed populations, but dispersal and migration within many natural populations is spatially limited. Such limitations can lead to enhanced variation among locations as different types become clustered in different places. Such clustering weakens competition between unlike types relative to competition between like types; thus, the rate by which a fitter type displaces an inferior competitor can be affected by the spatial scale of movement. In this paper, we use a birth-death model to show that limited migration can affect asexual populations by creating competitive refugia. We use a moment closure approach to show that as population structure is introduced by limiting migration, the equilibrial frequency of deleterious mutants increases. We support and extend the model through stochastic simulation, and we use a spatially explicit cellular automaton approach to corroborate the results. We discuss the implications of these results for standing variation in structured populations and adaptive valley crossing in Wright's "shifting balance" process.

  7. Combinatorial approaches with selected phytochemicals to increase antibiotic efficacy against Staphylococcus aureus biofilms.

    PubMed

    Abreu, Ana Cristina; Saavedra, Maria José; Simões, Lúcia C; Simões, Manuel

    2016-10-01

    Combinations of selected phytochemicals (reserpine, pyrrolidine, quinine, morin and quercetin) with antibiotics (ciprofloxacin, tetracycline and erythromycin) were tested on the prevention and control of Staphylococcus aureus biofilms. The phytochemicals were also studied for their ability to avoid antibiotic adaptation and to inhibit antibiotic efflux pumps. Morin, pyrrolidine and quercetin at subinhibitory concentrations had significant effects in biofilm prevention and/or control when applied alone and combined with antibiotics. Synergism between antibiotics and phytochemicals was found especially against biofilms of NorA overexpressing strain S. aureus SA1199B. This strain when growing with subinhibitory concentrations of ciprofloxacin developed increased tolerance to this antibiotic. However, this was successfully reversed by quinine and morin. In addition, reserpine and quercetin showed significant efflux pump inhibition. The overall results demonstrate the role of phytochemicals in co-therapies to promote more efficient treatments and decrease antimicrobial resistance to antibiotics, with substantial effects against S. aureus in both planktonic and biofilm states. PMID:27643487

  8. Thermal breeder fuel enrichment zoning

    DOEpatents

    Capossela, Harry J.; Dwyer, Joseph R.; Luce, Robert G.; McCoy, Daniel F.; Merriman, Floyd C.

    1992-01-01

    A method and apparatus for improving the performance of a thermal breeder reactor having regions of higher than average moderator concentration are disclosed. The fuel modules of the reactor core contain at least two different types of fuel elements, a high enrichment fuel element and a low enrichment fuel element. The two types of fuel elements are arranged in the fuel module with the low enrichment fuel elements located between the high moderator regions and the high enrichment fuel elements. Preferably, shim rods made of a fertile material are provided in selective regions for controlling the reactivity of the reactor by movement of the shim rods into and out of the reactor core. The moderation of neutrons adjacent the high enrichment fuel elements is preferably minimized as by reducing the spacing of the high enrichment fuel elements and/or using a moderator having a reduced moderating effect.

  9. Selective increase of the permeability of polarized epithelial cell monolayers by Helicobacter pylori vacuolating toxin.

    PubMed Central

    Papini, E; Satin, B; Norais, N; de Bernard, M; Telford, J L; Rappuoli, R; Montecucco, C

    1998-01-01

    The effects of the vacuolating toxin (VacA) released by pathogenic strains of Helicobacter pylori on several polarized epithelial monolayers were investigated. Trans-epithelial electric resistance (TER) of monolayers formed by canine kidney MDCK I, human gut T84, and murine mammary gland epH4, was lowered by acid-activated VacA. Independent of the cell type and of the starting TER value, VacA reduced it to a minimal value of 1,000-1,300 Omega x cm2. TER decrease was paralleled by a three- to fourfold increase of [14C]-mannitol (molecular weight 182.2) and a twofold increase of [14C]-sucrose (molecular weight 342.3) transmonolayer flux. On the contrary, transmembrane flux of the proinflammatory model tripeptide [14C]-N-formyl-Met-Leu-Phe (molecular weight 437.6), of [3H]-inuline (molecular weight 5,000) and of HRP (molecular weight 47,000) did not change. These data indicate that VacA increases paracellular epithelial permeability to molecules with molecular weight < 350-440. Accordingly, the epithelial permeability of Fe3+ and Ni2+ ions, essential for H. pylori survival in vivo, was also increased by VacA. High-resolution immunofluorescence and SDS-PAGE analysis failed to reveal alterations of junctional proteins ZO-1, occludin, cingulin, and E-cadherin. It is proposed that induction by VacA of a selective permeabilization of the epithelial paracellular route to low molecular weight molecules and ions may serve to supply nutrients, which favor H. pylori growth in vivo. PMID:9710450

  10. Chronic exposure to aluminum in drinking water increases inflammatory parameters selectively in the brain.

    PubMed

    Campbell, A; Becaria, A; Lahiri, D K; Sharman, K; Bondy, S C

    2004-02-15

    A link between aluminum (Al) exposure and age-related neurological disorders has long been proposed. Although the exact mechanism by which the metal may influence disease processes is unknown, there is evidence that exposure to Al causes an increase in both oxidative stress and inflammatory events. These processes have also been suggested to play a role in Alzheimer's disease (AD), and exposure to the metal may contribute to the disorder by potentiating these events. Al lactate (0.01, 0.1, and 1 mM) in drinking water for 10 weeks increased inflammatory processes in the brains of mice. The lowest of these levels is in the range found to increase the prevalence of AD in regions where the concentrations of the metal are elevated in residential drinking water (Flaten [2001] Brain Res. Bull. 55:187-196). Nuclear factor-kappaB as well as tumor necrosis factor-alpha (TNF-alpha) and interleukin 1alpha (IL-1alpha) levels were increased in the brains of treated animals. The mRNA for TNF-alpha was also up-regulated following treatment. Enhancement of glial fibrillary acidic protein levels and reactive microglia was seen in the striatum of Al-treated animals. The level of amyloid beta (Abeta40) was not significantly altered in the brains of exposed animals. Insofar as no parallel changes were observed in the serum or liver of treated animals, the proinflammatory effects of the metal may be selective to the brain. Al exposure may not be sufficient to cause abnormal production of the principal component of senile plaques directly but does exacerbate underlying events associated with brain aging and thus could contribute to progression of neurodegeneration.

  11. Composite blend polymer membranes with increased proton selectivity and lifetime for vanadium redox flow batteries

    SciTech Connect

    Chen, Dongyang; Kim, Soowhan; Sprenkle, Vincent L.; Hickner, Michael A.

    2013-06-01

    Composite membranes based on sulfonated fluorinated poly(arylene ether) (SFPAE) and poly(vinylidene fluoride-co-hexafluoropropene) (P(VDF-co-HFP)) were prepared with various contents of P(VDF-co-HFP) for vanadium redox flow battery (VRFB) applications. The compatibility and interaction of SFPAE and P(VDF-co-HFP) were characterized by atomic force microscopy, differential scanning calorimetry, and Fourier transform infrared spectroscopy. The water uptake, mechanical properties, thermal property, proton conductivity, VO2+ permeability and cell performance of the composite membranes were investigated in detail and compared to the pristine SFPAE membrane. It was found that SFPAE had good compatibility with P(VDF-co-HFP) and the incorporation of P(VDF-co-HFP) increased the mechanical properties, thermal property, and proton selectivity of the materials effectively. An SFPAE composite membrane with 10 wt.% P(VDF-co-HFP) exhibited a 44% increase in VRFB cell lifetime as compared to a cell with a pure SFPAE membrane. Therefore, the P(VDF-co-HFP) blending approach is a facile method for producing low-cost, high-performance VRFB membranes.

  12. Foraging patterns and prey selection in an increasing and expanding sea otter population

    USGS Publications Warehouse

    Laidre, K.L.; Jameson, R.J.

    2006-01-01

    Focal observations of sea otter (Enhydra lutris kenyoni) foraging patterns and prey selection were collected in coastal Washington between 1993 and 1999. Records consisted of 13,847 individual dives from 841 feeding bouts ranging from 1 min to >4 h. Average dive time was 55 s ?? 0.9 SE and average surface time was 45 s ?? 2.3 SE, irrespective of dive success. At least 77% of all dives (n = 10,636) were successful prey captures (dives in low light or of undetermined success were excluded). Prey capture success was significantly lower for subadults (63% ?? 5 SE) than adults (82% ?? 1 SE; P 60% red urchins (Strongylocentrotus franciscanus), with only 2 other prey species comprising >10% of their diet. Prey size and prey category were dominant predictor variables in generalized linear models of dive duration and postdive surface duration on successful dives. Significant increases in areal extent of surface canopy of giant kelp (Macrocystis integrifolia) and bull kelp (Nereocystis leutkeana) were found both in the outer coast and the Strait of Juan de Fuca (0.4-0.5 km2 per year, P < 0.05) and suggest increasing suitable habitat for a growing population. The growth and expansion of a small and isolated sea otter population provides a unique opportunity to examine the relationship between dietary diversity and population status and explore similarities and differences between trophic paradigms established for sea otter populations at other localities. ?? 2006 American Society of Mammalogists.

  13. Increasing density leads to generalization in both coarse-grained habitat selection and fine-grained resource selection in a large mammal.

    PubMed

    van Beest, Floris M; Uzal, Antonio; Vander Wal, Eric; Laforge, Michel P; Contasti, Adrienne L; Colville, David; McLoughlin, Philip D

    2014-01-01

    Density is a fundamental driver of many ecological processes including habitat selection. Theory on density-dependent habitat selection predicts that animals should be distributed relative to profitability of habitat, resulting in reduced specialization in selection (i.e. generalization) as density increases and competition intensifies. Despite mounting empirical support for density-dependent habitat selection using isodars to describe coarse-grained (interhabitat) animal movements, we know little of how density affects fine-grained resource selection of animals within habitats [e.g. using resource selection functions (RSFs)]. Using isodars and RSFs, we tested whether density simultaneously modified habitat selection and within-habitat resource selection in a rapidly growing population of feral horses (Equus ferus caballus Linnaeus; Sable Island, Nova Scotia, Canada; 42% increase in population size from 2008 to 2012). Among three heterogeneous habitat zones on Sable Island describing population clusters distributed along a west-east resource gradient (west-central-east), isodars revealed that horses used available habitat in a density-dependent manner. Intercepts and slopes of isodars demonstrated a pattern of habitat selection that first favoured the west, which generalized to include central and east habitats with increasing population size consistent with our understanding of habitat quality on Sable Island. Resource selection functions revealed that horses selected for vegetation associations similarly at two scales of extent (total island and within-habitat zone). When densities were locally low, horses were able to select for sites of the most productive forage (grasslands) relative to those of poorer quality. However, as local carrying capacity was approached, selection for the best of available forage types weakened while selection for lower-quality vegetation increased (and eventually exceeded that of grasslands). Isodars can effectively describe coarse

  14. Differentially Expressed Genes in Endometrium and Corpus Luteum of Holstein Cows Selected for High and Low Fertility Are Enriched for Sequence Variants Associated with Fertility.

    PubMed

    Moore, Stephen G; Pryce, Jennie E; Hayes, Ben J; Chamberlain, Amanda J; Kemper, Kathryn E; Berry, Donagh P; McCabe, Matt; Cormican, Paul; Lonergan, Pat; Fair, Trudee; Butler, Stephen T

    2016-01-01

    Despite the importance of fertility in humans and livestock, there has been little success dissecting the genetic basis of fertility. Our hypothesis was that genes differentially expressed in the endometrium and corpus luteum on Day 13 of the estrous cycle between cows with either good or poor genetic merit for fertility would be enriched for genetic variants associated with fertility. We combined a unique genetic model of fertility (cattle that have been selected for high and low fertility and show substantial difference in fertility) with gene expression data from these cattle and genome-wide association study (GWAS) results in ∼20,000 cattle to identify quantitative trait loci (QTL) regions and sequence variants associated with genetic variation in fertility. Two hundred and forty-five QTL regions and 17 sequence variants associated primarily with prostaglandin F2alpha, steroidogenesis, mRNA processing, energy status, and immune-related processes were identified. Ninety-three of the QTL regions were validated by two independent GWAS, with signals for fertility detected primarily on chromosomes 18, 5, 7, 8, and 29. Plausible causative mutations were identified, including one missense variant significantly associated with fertility and predicted to affect the protein function of EIF4EBP3. The results of this study enhance our understanding of 1) the contribution of the endometrium and corpus luteum transcriptome to phenotypic fertility differences and 2) the genetic architecture of fertility in dairy cattle. Including these variants in predictions of genomic breeding values may improve the rate of genetic gain for this critical trait.

  15. Selective trace enrichment of acidic pharmaceuticals in real water and sediment samples based on solid-phase extraction using multi-templates molecularly imprinted polymers.

    PubMed

    Duan, Yan-Ping; Dai, Chao-Meng; Zhang, Ya-Lei; Ling-Chen

    2013-01-01

    A novel multi-templates molecularly imprinted polymer (MIP), using acidic pharmaceuticals mixture (ibuprofen (IBP), naproxen (NPX), ketoprofen (KEP), diclofenac (DFC), and clofibric acid (CA)) as the template, was prepared as solid-phase extraction (SPE) material for the quantitative enrichment of acidic pharmaceuticals in environmental samples and off-line coupled with liquid chromatography-mass spectrometry (LC/MS/MS). Washing solvent was optimized in terms of kind and volume for removing the matrix constituents nonspecifically adsorbed on the MIP. When 1L of water sample spiked at 1μg/L was loaded onto the cartridge, the binding capacity of the MIP cartridge were 48.7μg/g for KEP, 60.7μg/g for NPX, 52μg/g for CA, 61.3μg/g for DFC and 60.7μg/g for IBP, respectively, which are higher than those of the commercial single template MIP in organic medium (e.g. toluene) reported in the literature. Recoveries of the five acidic pharmaceuticals extracted from 1L of real water samples such as lake water and wastewater spiked at 1μg/L were more than 95%. The recoveries of acidic pharmaceuticals extracted from 10-g sediment sample spiked at the 10ng/g level were in the range of 77.4-90.6%. To demonstrate the potential of the MIP obtained, a comparison with commercial C18 SPE cartridge was performed. Molecularly imprinted solid-phase extraction (MISPE) cartridge showed higher recoveries than commercial C18 SPE cartridge for acidic pharmaceuticals. These results showed the suitability of the MISPE method for the selective extraction of a group of structurally related compounds such as acidic pharmaceuticals. PMID:23245900

  16. Increasing the selectivity and sensitivity of gas sensors for the detection of explosives

    NASA Astrophysics Data System (ADS)

    Mallin, Daniel

    Over the past decade, the use of improvised explosive devices (IEDs) has increased, domestically and internationally, highlighting a growing need for a method to quickly and reliably detect explosive devices in both military and civilian environments before the explosive can cause damage. Conventional techniques have been successful in explosive detection, however they typically suffer from enormous costs in capital equipment and maintenance, costs in energy consumption, sampling, operational related expenses, and lack of continuous and real-time monitoring. The goal was thus to produce an inexpensive, portable sensor that continuously monitors the environment, quickly detects the presence of explosive compounds and alerts the user. In 2012, here at URI, a sensor design was proposed for the detection of triacetone triperoxide (TATP). The design entailed a thermodynamic gas sensor that measures the heat of decomposition between trace TATP vapor and a metal oxide catalyst film. The sensor was able to detect TATP vapor at the part per million level (ppm) and showed great promise for eventual commercial use, however, the sensor lacked selectivity. Thus, the specific objective of this work was to take the original sensor design proposed in 2012 and to make several key improvements to advance the sensor towards commercialization. It was demonstrated that a sensor can be engineered to detect TATP and ignore the effects of interferent H2O2 molecules by doping SnO2 films with varying amounts of Pd. Compared with a pure SnO2 catalyst, a SnO2, film doped with 8 wt. % Pd had the highest selectivity between TATP and H2O2. Also, at 12 wt. % Pd, the response to TATP and H2O2 was enhanced, indicating that sensitivity, not only selectivity, can be increased by modifying the composition of the catalyst. An orthogonal detection system was demonstrated. The platform consists of two independent sensing mechanisms, one thermodynamic and one conductometric, which take measurements from

  17. Selective apoptosis of pluripotent mouse and human stem cells by novel ceramide analogues prevents teratoma formation and enriches for neural precursors in ES cell–derived neural transplants

    PubMed Central

    Bieberich, Erhard; Silva, Jeane; Wang, Guanghu; Krishnamurthy, Kannan; Condie, Brian G.

    2004-01-01

    The formation of stem cell–derived tumors (teratomas) is observed when engrafting undifferentiated embryonic stem (ES) cells, embryoid body–derived cells (EBCs), or mammalian embryos and is a significant obstacle to stem cell therapy. We show that in tumors formed after engraftment of EBCs into mouse brain, expression of the pluripotency marker Oct-4 colocalized with that of prostate apoptosis response-4 (PAR-4), a protein mediating ceramide-induced apoptosis during neural differentiation of ES cells. We tested the ability of the novel ceramide analogue N-oleoyl serinol (S18) to eliminate mouse and human Oct-4(+)/PAR-4(+) cells and to increase the proportion of nestin(+) neuroprogenitors in EBC-derived cell cultures and grafts. S18-treated EBCs persisted in the hippocampal area and showed neuronal lineage differentiation as indicated by the expression of β-tubulin III. However, untreated cells formed numerous teratomas that contained derivatives of endoderm, mesoderm, and ectoderm. Our results show for the first time that ceramide-induced apoptosis eliminates residual, pluripotent EBCs, prevents teratoma formation, and enriches the EBCs for cells that undergo neural differentiation after transplantation. PMID:15545317

  18. Enrichment Strategies in Phosphoproteomics.

    PubMed

    Leitner, Alexander

    2016-01-01

    The comprehensive study of the phosphoproteome is heavily dependent on appropriate enrichment strategies that are most often, but not exclusively, carried out on the peptide level. In this chapter, I give an overview of the most widely used techniques. In addition to dedicated antibodies, phosphopeptides are enriched by their selective interaction with metals in the form of chelated metal ions or metal oxides. The negative charge of the phosphate group is also exploited in a variety of chromatographic fractionation methods that include different types of ion exchange chromatography, hydrophilic interaction chromatography (HILIC), and electrostatic repulsion HILIC (ERLIC) chromatography. Selected examples from the literature will demonstrate how a combination of these techniques with current high-performance mass spectrometry enables the identification of thousands of phosphorylation sites from various sample types. PMID:26584921

  19. Experiments for practical education in process parameter optimization for selective laser sintering to increase workpiece quality

    NASA Astrophysics Data System (ADS)

    Reutterer, Bernd; Traxler, Lukas; Bayer, Natascha; Drauschke, Andreas

    2016-04-01

    Selective Laser Sintering (SLS) is considered as one of the most important additive manufacturing processes due to component stability and its broad range of usable materials. However the influence of the different process parameters on mechanical workpiece properties is still poorly studied, leading to the fact that further optimization is necessary to increase workpiece quality. In order to investigate the impact of various process parameters, laboratory experiments are implemented to improve the understanding of the SLS limitations and advantages on an educational level. Experiments are based on two different workstations, used to teach students the fundamentals of SLS. First of all a 50 W CO2 laser workstation is used to investigate the interaction of the laser beam with the used material in accordance with varied process parameters to analyze a single-layered test piece. Second of all the FORMIGA P110 laser sintering system from EOS is used to print different 3D test pieces in dependence on various process parameters. Finally quality attributes are tested including warpage, dimension accuracy or tensile strength. For dimension measurements and evaluation of the surface structure a telecentric lens in combination with a camera is used. A tensile test machine allows testing of the tensile strength and the interpreting of stress-strain curves. The developed laboratory experiments are suitable to teach students the influence of processing parameters. In this context they will be able to optimize the input parameters depending on the component which has to be manufactured and to increase the overall quality of the final workpiece.

  20. Energy-aware Gateway Selection for increasing the lifetime of Wireless Body Area Sensor Networks.

    PubMed

    Bayilmis, Cuneyt; Younis, Mohamed

    2012-06-01

    A Wireless Body Area Sensor Network (WBASN) is composed of a set of sensor nodes, placed on, near or within a human body. WBASNs opt to continuously monitor the health conditions of individuals under medical risk, e.g., elders and chronically ill people, without keeping them in a hospital or restraining their motion. A WBASN needs to stay connected to local or wide area networks using wireless technologies in order to send sensor readings to a medical center. The WBASN nodes are implanted within the human body and would thus have limited energy supply. Since the mission of the WBASN is very critical, increasing the lifetime of nodes is essential in order to maintain both practicality and effectiveness. This paper presents a new Gateway Selection Algorithm (GSA) that factors in the use of energy harvesting technologies and dynamically picks the most suitable WBASN node that serves as a gateway to other wireless networks. The goal of GSA is to balance the load among the nodes by adaptively changing the gateway node in WBASN depending on the energy reserve of nodes. Computer modeling and simulations of the proposed GSA are carried out using OPNET. The simulation results demonstrate the effectiveness of the proposed GSA approach. PMID:21057885

  1. Anticoagulant therapy of cancer patients: Will patient selection increase overall survival?

    PubMed

    Spek, C Arnold; Versteeg, Henri H; Borensztajn, Keren S

    2015-08-31

    Already since the early 1800s, it has been recognised that malignancies may provoke thromboembolic complications, and indeed cancer patients are at increased risk of developing venous thrombosis. Interestingly, case control studies of deep-vein thrombosis suggested that low-molecular-weight heparin (LMWH) improved survival of cancer patients. This led to the hypothesis that cancer cells might 'take advantage' of a hypercoagulable state to more efficiently metastasise. Initial randomised placebo control trials showed that LMWH improve overall survival of cancer patients, especially in those patients with a relatively good prognosis. The failure of recent phase III trials, however, tempers enthusiasm for anticoagulant treatment in cancer patients despite an overwhelming body of literature showing beneficial effects of anticoagulants in preclinical models. Instead of discarding LMWH as potential (co)treatment modality in cancer patients, these disappointing recent trials should guide future preclinical research on anticoagulants in cancer biology. Most and for all, the underlying mechanisms by which coagulation drives tumour progression need to be elucidated. This could ultimately allow selection of cancer patients most likely to benefit from anticoagulant treatment and/or from targeted therapy downstream of coagulation factor signalling.

  2. A single positively selected West Nile viral mutation confers increased virogenesis in American crows

    PubMed Central

    Brault, Aaron C; Huang, Claire Y-H; Langevin, Stanley A; Kinney, Richard M; Bowen, Richard A; Ramey, Wanichaya N; Panella, Nicholas A; Holmes, Edward C; Powers, Ann M; Miller, Barry R

    2008-01-01

    West Nile virus (WNV), first recognized in North America in 1999, has been responsible for the largest arboviral epiornitic and epidemic of human encephalitis in recorded history. Despite the well-described epidemiological patterns of WNV in North America, the basis for the emergence of WNV-associated avian pathology, particularly in the American crow (AMCR) sentinel species, and the large scale of the North American epidemic and epiornitic is uncertain. We report here that the introduction of a T249P amino acid substitution in the NS3 helicase (found in North American WNV) in a low-virulence strain was sufficient to generate a phenotype highly virulent to AMCRs. Furthermore, comparative sequence analyses of full-length WNV genomes demonstrated that the same site (NS3-249) was subject to adaptive evolution. These phenotypic and evolutionary results provide compelling evidence for the positive selection of a mutation encoding increased viremia potential and virulence in the AMCR sentinel bird species. PMID:17694056

  3. Perspectives on Job Enrichment and Productivity.

    ERIC Educational Resources Information Center

    Suojanen, Waino W., Ed.; And Others

    The book of reading focuses on the state of job enrichment in the United States today, as well as some of its international implications. Featured in the book are 20 selected working papers analyzing the development and use of job enrichment in various types of organizations, union response to job enrichment, and its outlook for the future. The…

  4. Science Student Enrichment Opportunities.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento.

    This document was developed with the intention of increasing California public school students' awareness of and participation in science-related enrichment activities. Some of the activities are intended for participation by individuals, while others are meant for teams of students. These annual events are listed in chronological order for a…

  5. [Change in biochemical composition of amaranth leaves as a result of selection for increased level of amaranthine pigment].

    PubMed

    Gins, M S; Gins, V K; Kononkov, P F

    2002-01-01

    The composition and content of secondary compounds produced by the shikimate pathway and the contents of protein and cellulose were determined in leaves of amaranth (Amaranthus tricolor L.) K-99 and the cultivar Valentina raised from it by family selection and enriched in the pigment amaranthine. It was found that intense biosynthesis of amaranthine, tyrosine, and phenylalanine resulted in a decrease in the contents of lignin, protein, and cellulose in leaves of Valentina by comparison with K-99 and in changed the morphological traits: color deepening and a decrease in leaf density. It is concluded that amaranth biosynthesis is related to nitrogen metabolism and amaranthine is an intermediate involved in conversion of nitrogen compounds in the cell.

  6. 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...

  7. Clinically used selective oestrogen receptor modulators increase LDL receptor activity in primary human lymphocytes

    PubMed Central

    Cerrato, F; Fernández-Suárez, M E; Alonso, R; Alonso, M; Vázquez, C; Pastor, O; Mata, P; Lasunción, M A; Gómez-Coronado, D

    2015-01-01

    Background and Purpose Treatment with selective oestrogen receptor modulators (SERMs) reduces low-density lipoprotein (LDL) cholesterol levels. We assessed the effect of tamoxifen, raloxifene and toremifene and their combinations with lovastatin on LDL receptor activity in lymphocytes from normolipidaemic and familial hypercholesterolaemic (FH) subjects, and human HepG2 hepatocytes and MOLT-4 lymphoblasts. Experimental Approach Lymphocytes were isolated from peripheral blood, treated with different compounds, and 1,1′-dioctadecyl-3,3,3,3′-tetramethylindocarbocyanine perchlorate (DiI)-labelled LDL uptake was analysed by flow cytometry. Key Results Tamoxifen, toremifene and raloxifene, in this order, stimulated DiI-LDL uptake by lymphocytes by inhibiting LDL-derived cholesterol trafficking and subsequent down-regulation of LDL receptor expression. Differently to what occurred in HepG2 and MOLT-4 cells, only tamoxifen consistently displayed a potentiating effect with lovastatin in primary lymphocytes. The SERM-mediated increase in LDL receptor activity was not altered by the anti-oestrogen ICI 182 780 nor was it reproduced by 17β-oestradiol. However, the tamoxifen-active metabolite endoxifen was equally effective as tamoxifen. The SERMs produced similar effects on LDL receptor activity in heterozygous FH lymphocytes as in normal lymphocytes, although none of them had a potentiating effect with lovastatin in heterozygous FH lymphocytes. The SERMs had no effect in homozygous FH lymphocytes. Conclusions and Implications Clinically used SERMs up-regulate LDL receptors in primary human lymphocytes. There is a mild enhancement between SERMs and lovastatin of lymphocyte LDLR activity, the potentiation being greater in HepG2 and MOLT-4 cells. The effect of SERMs is independent of oestrogen receptors but is preserved in the tamoxifen-active metabolite endoxifen. This mechanism may contribute to the cholesterol-lowering action of SERMs. PMID:25395200

  8. Benefit of multiple trait selection to increase reproductive traits: experimental evidence from golden hamsters.

    PubMed

    Satoh, M; Nishida, A; van Arendonk, J A; van der Lende, T

    1997-12-01

    Fifteen generations of selection were conducted to study responses for litter size at birth (LSB), weight at weaning of standardized litter (LWW), and individual body weight at 8 wk of age (BW8) using golden hamsters as an experimental model for pigs. The experiment involved three lines: selection on an aggregate breeding value of LSB, LWW, and BW8 (line W); selection on an aggregate breeding value of LSB and LWW (line R); and a randomly selected control (line C). Selection in W and R was based on breeding values from a multiple trait animal model. Restricted maximum likelihood with an animal model was used to estimate genetic parameters and genetic trends. Heritability estimates for LSB, LWW, and BW8 were .10, .47, and .52, respectively, and genetic correlations between traits were all positive. The mean estimated breeding value (EBV) for LSB in generation 15 was +2.2 pups in W and R. The mean EBV for LWW in generation 15 was +318 g for W and +174 g for R, and for BW8 means were +64 g and +24 g, respectively. Average inbreeding at generation 16 was 13.4, 19.5, and 8.0% for W, R, and C, respectively. Including BW8 in the selection criterion reduced inbreeding and had a beneficial effect on selection responses in LSB, LWW, and BW8.

  9. Phosphopeptide enrichment with inorganic nanofibers prepared by forcespinning technology.

    PubMed

    Krenkova, Jana; Moravkova, Jaroslava; Buk, Jan; Foret, Frantisek

    2016-01-01

    Efficient selective sample enrichment is often a key procedure in protocols for analyses of complex samples. This applies not only to trace sample components but also to species with weak detection response. For example enrichment of phosphopeptides using selective affinity techniques prior to mass spectrometry analysis is necessary to increase detection sensitivity of phosphopeptides from highly complex peptide mixtures. In this work we have developed inorganic nanofibrous materials based on titanium or zirconium dioxides for selective and efficient enrichment of phosphopeptides for MALDI/MS detection. In comparison to the common bead based materials the presented nanofibrous materials exhibit much higher permeability allowing their use not only for batch mode or packed in the column operation, but also in the pipette tip format without the need for high pressure. Both the methods of preparation and characterization of the resulting materials are presented. PMID:26689825

  10. Group-Level Selection Increases Cooperation in the Public Goods Game.

    PubMed

    Eckel, Catherine C; Fatas, Enrique; Godoy, Sara; Wilson, Rick K

    2016-01-01

    When groups compete for resources, some groups will be more successful than others, forcing out less successful groups. Group-level selection is the most extreme form of group competition, where the weaker group ceases to exist, becoming extinct. We implement group-level selection in a controlled laboratory experiment in order to study its impact on human cooperation. The experiment uses variations on the standard linear public goods game. Group-level selection operates through competition for survival: the least successful, lowest-earning groups become extinct, in the sense that they no longer are able to play the game. Additional control treatments include group comparison without extinction, and extinction of the least successful individuals across groups. We find that group-level extinction produces very high contributions to the provision of the public good, while group comparison alone or individual extinction fail to cause higher contributions. Our results provide stark evidence that group-level selection enhances within-group cooperation.

  11. Click Synthesis of Hydrophilic Maltose-Functionalized Iron Oxide Magnetic Nanoparticles Based on Dopamine Anchors for Highly Selective Enrichment of Glycopeptides.

    PubMed

    Bi, Changfen; Zhao, Yingran; Shen, Lijin; Zhang, Kai; He, Xiwen; Chen, Langxing; Zhang, Yukui

    2015-11-11

    The development of methods to isolate and enrich low-abundance glycopeptides from biological samples is crucial to glycoproteomics. Herein, we present an easy and one-step surface modification strategy to prepare hydrophilic maltose functionalized Fe3O4 nanoparticles (NPs). First, based on the chelation of the catechol ligand with iron atoms, azido-terminated dopamine (DA) derivative was assembled on the surface of magnetic Fe3O4 nanoparticles by sonication. Second, the hydrophilic maltose-functionalized Fe3O4 (Fe3O4-DA-Maltose) NPs were obtained via copper(I)-catalyzed azide-alkyne cycloaddition (click chemistry). The morphology, structure, and composition of Fe3O4-DA-Maltose NPs were investigated by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), X-ray photoelectron spectrometer (XPS), and vibrating sample magnetometer (VSM). Meanwhile, hydrophilicity of the obtained NPs was evaluated by water contact angle measurement. The hydrophilic Fe3O4-DA-Maltose NPs were applied in isolation and enrichment of glycopeptides from horseradish peroxidase (HRP), immunoglobulin (IgG) digests. The MALDI-TOF mass spectrometric analysis indicated that the novel NPs exhibited high detection sensitivity in enrichment from HRP digests at concentration as low as 0.05 ng μL(-1), a large binding capacity up to 43 mg g(-1), and good recovery for glycopeptides enrichment (85-110%). Moreover, the Fe3O4-DA-Maltose NPs were applied to enrich glycopeptides from human renal mesangial cells (HRMC) for identification of N-glycosylation sites. Finally, we identified 115 different N-linked glycopeptides, representing 93 gene products and 124 glycosylation sites in HRMC.

  12. Group-Level Selection Increases Cooperation in the Public Goods Game

    PubMed Central

    Eckel, Catherine C.; Fatas, Enrique; Godoy, Sara

    2016-01-01

    When groups compete for resources, some groups will be more successful than others, forcing out less successful groups. Group-level selection is the most extreme form of group competition, where the weaker group ceases to exist, becoming extinct. We implement group-level selection in a controlled laboratory experiment in order to study its impact on human cooperation. The experiment uses variations on the standard linear public goods game. Group-level selection operates through competition for survival: the least successful, lowest-earning groups become extinct, in the sense that they no longer are able to play the game. Additional control treatments include group comparison without extinction, and extinction of the least successful individuals across groups. We find that group-level extinction produces very high contributions to the provision of the public good, while group comparison alone or individual extinction fail to cause higher contributions. Our results provide stark evidence that group-level selection enhances within-group cooperation. PMID:27574971

  13. Analyzing Marketing Strategies Designed To Increase Minority Student Enrollment at Selected Urban Community Colleges.

    ERIC Educational Resources Information Center

    Galbraith, James D.

    A study was conducted to identify the most effective marketing techniques used by urban community colleges to recruit minority students. A 16-item, open-ended questionnaire was used in telephone interviews with marketing officials at 24 colleges. The colleges selected for the survey served an urban community of 100,000 or more residents, had a…

  14. Group-Level Selection Increases Cooperation in the Public Goods Game.

    PubMed

    Eckel, Catherine C; Fatas, Enrique; Godoy, Sara; Wilson, Rick K

    2016-01-01

    When groups compete for resources, some groups will be more successful than others, forcing out less successful groups. Group-level selection is the most extreme form of group competition, where the weaker group ceases to exist, becoming extinct. We implement group-level selection in a controlled laboratory experiment in order to study its impact on human cooperation. The experiment uses variations on the standard linear public goods game. Group-level selection operates through competition for survival: the least successful, lowest-earning groups become extinct, in the sense that they no longer are able to play the game. Additional control treatments include group comparison without extinction, and extinction of the least successful individuals across groups. We find that group-level extinction produces very high contributions to the provision of the public good, while group comparison alone or individual extinction fail to cause higher contributions. Our results provide stark evidence that group-level selection enhances within-group cooperation. PMID:27574971

  15. Discovery of tankyrase inhibiting flavones with increased potency and isoenzyme selectivity.

    PubMed

    Narwal, Mohit; Koivunen, Jarkko; Haikarainen, Teemu; Obaji, Ezeogo; Legala, Ongey E; Venkannagari, Harikanth; Joensuu, Päivi; Pihlajaniemi, Taina; Lehtiö, Lari

    2013-10-24

    Tankyrases are ADP-ribosyltransferases that play key roles in various cellular pathways, including the regulation of cell proliferation, and thus, they are promising drug targets for the treatment of cancer. Flavones have been shown to inhibit tankyrases and we report here the discovery of more potent and selective flavone derivatives. Commercially available flavones with single substitutions were used for structure-activity relationship studies, and cocrystal structures of the 18 hit compounds were analyzed to explain their potency and selectivity. The most potent inhibitors were also tested in a cell-based assay, which demonstrated that they effectively antagonize Wnt signaling. To assess selectivity, they were further tested against a panel of homologous human ADP-ribosyltransferases. The most effective compound, 22 (MN-64), showed 6 nM potency against tankyrase 1, isoenzyme selectivity, and Wnt signaling inhibition. This work forms a basis for rational development of flavones as tankyrase inhibitors and guides the development of other structurally related inhibitors. PMID:24116873

  16. Synthesis of a new type of echinus-like Fe3O4@TiO2 core-shell-structured microspheres and their applications in selectively enriching phosphopeptides and removing phospholipids.

    PubMed

    Li, Hua; Shi, Xianzhe; Qiao, Lizhen; Lu, Xin; Xu, Guowang

    2013-02-01

    Some compounds of low abundance in biological samples play important roles in bioprocesses. However, the detection of these compounds at inherently trace concentrations with interference from a complex matrix is difficult. New materials for sample pretreatment are essential for the removal of interferences and for selective enrichment. In this study, echinus-like Fe(3)O(4)@TiO(2) core-shell-structured microspheres (echinus-like microspheres) have been synthesized for the first time. Rutile phase TiO(2) nanorods with a length of approximately 300 nm and width of approximately 60 nm are arranged regularly on the surface of the microspheres. This novel type of material exhibited good selectivity and adsorption capacity toward phosphate-containing compounds. In proteomics research, the echinus-like microspheres were used to selectively enrich phosphopeptides from complex peptide mixtures. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/MS) analysis showed that fourteen phosphopeptides were detected from α-casein tryptic digests after enrichment. Even in peptide mixtures that contained highly abundant nonphosphorylated peptides with interference from bovine serum albumin, these phospopeptides could still be selectively trapped with little nonspecific adsorption. In metabolomics studies, the echinus-like microspheres were further used to selectively remove phosphocholines (PCs) and lysophosphocholines (LPCs), which are the main matrix interferences for the detection of metabolites of low abundance in plasma. Liquid chromatography-quadrupole time-of-flight mass spectrometry was used to perform the metabolic profiling of plasma. The high concentrations of PCs and LPCs were effectively eliminated, and many endogenous metabolites of low abundance were enhanced or even observed for the first time. All of the results suggest that echinus-like microspheres have potential applications in proteomics and metabolomics to improve the

  17. Bayesian approach increases accuracy when selecting cowpea genotypes with high adaptability and phenotypic stability.

    PubMed

    Barroso, L M A; Teodoro, P E; Nascimento, M; Torres, F E; Dos Santos, A; Corrêa, A M; Sagrilo, E; Corrêa, C C G; Silva, F A; Ceccon, G

    2016-01-01

    This study aimed to verify that a Bayesian approach could be used for the selection of upright cowpea genotypes with high adaptability and phenotypic stability, and the study also evaluated the efficiency of using informative and minimally informative a priori distributions. Six trials were conducted in randomized blocks, and the grain yield of 17 upright cowpea genotypes was assessed. To represent the minimally informative a priori distributions, a probability distribution with high variance was used, and a meta-analysis concept was adopted to represent the informative a priori distributions. Bayes factors were used to conduct comparisons between the a priori distributions. The Bayesian approach was effective for selection of upright cowpea genotypes with high adaptability and phenotypic stability using the Eberhart and Russell method. Bayes factors indicated that the use of informative a priori distributions provided more accurate results than minimally informative a priori distributions. PMID:26985961

  18. Associative conditioning analog selectively increases cAMP levels of tail sensory neurons in Aplysia.

    PubMed

    Ocorr, K A; Walters, E T; Byrne, J H

    1985-04-01

    Bilateral clusters of sensory neurons in the pleural ganglia of Aplysia contain cells involved in a defensive tail withdrawal reflex. These cells exhibit heterosynaptic facilitation in response to noxious skin stimulation that can be mimicked by the application of serotonin. Recently it has been shown that this facilitation can be selectively amplified by the application of a classical conditioning procedure to individual sensory neurons. We now report that an analog of this classical conditioning paradigm produces a selective amplification of the cAMP content of isolated sensory neuron clusters. The enhancement is achieved within a single trial and appears to be localized to the sensory neurons. These results indicate that a pairing-specific enhancement of cAMP levels may be a biochemical mechanism for associative neuronal modifications and perhaps learning.

  19. Bayesian approach increases accuracy when selecting cowpea genotypes with high adaptability and phenotypic stability.

    PubMed

    Barroso, L M A; Teodoro, P E; Nascimento, M; Torres, F E; Dos Santos, A; Corrêa, A M; Sagrilo, E; Corrêa, C C G; Silva, F A; Ceccon, G

    2016-03-11

    This study aimed to verify that a Bayesian approach could be used for the selection of upright cowpea genotypes with high adaptability and phenotypic stability, and the study also evaluated the efficiency of using informative and minimally informative a priori distributions. Six trials were conducted in randomized blocks, and the grain yield of 17 upright cowpea genotypes was assessed. To represent the minimally informative a priori distributions, a probability distribution with high variance was used, and a meta-analysis concept was adopted to represent the informative a priori distributions. Bayes factors were used to conduct comparisons between the a priori distributions. The Bayesian approach was effective for selection of upright cowpea genotypes with high adaptability and phenotypic stability using the Eberhart and Russell method. Bayes factors indicated that the use of informative a priori distributions provided more accurate results than minimally informative a priori distributions.

  20. Increased significance of food wastes: selective recovery of added-value compounds.

    PubMed

    Reis, Igor A O; Santos, Samuel B; Santos, Ludmila A; Oliveira, Naiana; Freire, Mara G; Pereira, Jorge F B; Ventura, Sónia P M; Coutinho, João A P; Soares, Cleide M F; Lima, Álvaro S

    2012-12-15

    A single-step selective separation of two food additives was investigated using alcohol-salt aqueous two-phase systems (ATPS). The selective partitioning of two of the most used additives from a processed food waste material, vanillin and l-ascorbic acid, was successfully accomplished. The results obtained prove that alcohol-salt ATPS can be easily applied as cheaper processes for the selective recovery of valuable chemical products from food wastes and other sources. As a first approach, the phase diagrams of ATPS composed of different alcohol+inorganic salt+water were determined at 298 (± 1)K and atmospheric pressure. The influence of methanol, ethanol, 1-propanol, and 2-propanol and K(3)PO(4), K(2)HPO(4) or KH(2)PO(4)/K(2)HPO(4) in the design of the phase diagrams was addressed. After the evaluation of the phase diagrams behaviour, the influence of the phase forming constituents was assessed towards the partition coefficients and recovery percentages of vanillin and l-ascorbic acid among the coexisting phases. Both model systems and real processed food waste materials were employed. Using these ATPS as partitioning systems it is possible to recover and separate vanillin, which migrates for the alcohol-rich phase, from l-ascorbic acid, which preferentially partitions for the salt-rich phase. PMID:22980828

  1. A case study of spatial variation and enrichment of selected elements in ambient particulate matter around a large coal-fired power station in central India.

    PubMed

    Sharma, Rajnikant; Pervez, Shamsh

    2004-12-01

    The dominant use of coal in power sectors has been associated with adverse environmental impacts. Ambient air monitoring for the two size fractions of particulate matter, respirable suspended particulate matter (RSPM) and non-respirable suspended particulate matter (NRSPM) in the downwind and upwind directions of a large coal-fired power station in central India, was carried out. Collected samples of ambient particulate matter were analysed atomic absorption spectrophotometrically for 15 elements. Spatial variability in elemental composition of RSPM and NRSPM and the degree of enrichment of these toxic metals in RSPM were investigated. A significant spatial variability for the elements in RSPM and NRSPM and higher degrees of enrichment of the elements were observed.

  2. Environmental enrichment for aquatic animals.

    PubMed

    Corcoran, Mike

    2015-05-01

    Aquatic animals are the most popular pets in the United States based on the number of owned pets. They are popular display animals and are increasingly used in research settings. Enrichment of captive animals is an important element of zoo and laboratory medicine. The importance of enrichment for aquatic animals has been slower in implementation. For a long time, there was debate over whether or not fish were able to experience pain or form long-term memories. As that debate has reduced and the consciousness of more aquatic animals is accepted, the need to discuss enrichment for these animals has increased.

  3. Expensive Enrichment

    ERIC Educational Resources Information Center

    Resnikoff, Marvin

    1975-01-01

    This article presents an economic analysis of the nuclear fuel reprocessing industry. It indicates that while environmental safety devices have improved the working conditions, they have also added ever-increasing costs to this necessary process. (MA)

  4. Selection against abdominal fat percentage may increase intramuscular fat content in broilers.

    PubMed

    Leng, L; Zhang, H; Dong, J Q; Wang, Z P; Zhang, X Y; Wang, S Z; Cao, Z P; Li, Y M; Li, H

    2016-10-01

    Excessive abdominal fat content (AFC) has negative impacts on feed efficiency and carcass quality. Unlike AFC, intramuscular fat content (IMFC) could be a favourable trait, which has a positive impact on meat quality. To meet consumers' needs, a long-term goal of broiler breeders is to decrease AFC and improve the IMFC simultaneously. The current study was designed to investigate the relationship between AFC and IMFC and to compare IMFC, including the pectoral major muscle fat content (PIMFC) and intramuscular fat content of leg muscle (LIMFC), between two broiler lines divergently selected for abdominal fat percentage over 17 generations. The results showed that there was a significant difference in PIMFC and LIMFC between the two lines in all five generation populations used. The birds in the lean line had significantly lower AFC but higher PIMFC and LIMFC than the birds in the fat line. We also detected differences in the liver fat content (LFC) between the two lines and the results showed that birds in the fat line had significant higher LFC than birds in the lean line. Our results indicated that a desirable broiler line with higher IMFC but lower AFC could be obtained by genetic selection.

  5. Selection against abdominal fat percentage may increase intramuscular fat content in broilers.

    PubMed

    Leng, L; Zhang, H; Dong, J Q; Wang, Z P; Zhang, X Y; Wang, S Z; Cao, Z P; Li, Y M; Li, H

    2016-10-01

    Excessive abdominal fat content (AFC) has negative impacts on feed efficiency and carcass quality. Unlike AFC, intramuscular fat content (IMFC) could be a favourable trait, which has a positive impact on meat quality. To meet consumers' needs, a long-term goal of broiler breeders is to decrease AFC and improve the IMFC simultaneously. The current study was designed to investigate the relationship between AFC and IMFC and to compare IMFC, including the pectoral major muscle fat content (PIMFC) and intramuscular fat content of leg muscle (LIMFC), between two broiler lines divergently selected for abdominal fat percentage over 17 generations. The results showed that there was a significant difference in PIMFC and LIMFC between the two lines in all five generation populations used. The birds in the lean line had significantly lower AFC but higher PIMFC and LIMFC than the birds in the fat line. We also detected differences in the liver fat content (LFC) between the two lines and the results showed that birds in the fat line had significant higher LFC than birds in the lean line. Our results indicated that a desirable broiler line with higher IMFC but lower AFC could be obtained by genetic selection. PMID:26931078

  6. The effect of chlorpyrifos on thermogenic capacity of bank voles selected for increased aerobic exercise metabolism.

    PubMed

    Dheyongera, Geoffrey; Grzebyk, Katherine; Rudolf, Agata M; Sadowska, Edyta T; Koteja, Paweł

    2016-04-01

    Agro-chemicals potentially cause adverse effects in non-target organisms. The rate of animal energy metabolism can influence their susceptibility to pesticides by influencing food consumption, biotransformation and elimination rates of toxicants. We used experimental evolution to study the effects of inherent differences in energy metabolism rate and exposure to the organophosphate insecticide, chlorpyrifos (CPF) on thermogenic capacity in a wild rodent, the bank vole (Myodes = Clethrionomys glareolus). The voles were sampled from four replicate lines selected for high swim-induced aerobic metabolism (A) and four unselected control (C) lines. Thermogenic capacity, measured as the maximum cold-induced rate of oxygen consumption (VO2cold), was higher in the A - than C lines, and it decreased after continuous exposure to CPF via food or after a single dose administered via oral gavage, but only when measured shortly after exposure. VO2cold measured 24 h after repeated exposure was not affected. In addition, gavage with a single dose led to decreased food consumption and loss in body mass. Importantly, the adverse effects of CPF did not differ between the selected and control lines. Therefore, exposure to CPF has adverse effects on thermoregulatory performance and energy balance in this species. The effects are short-lived and their magnitude is not associated with the inherent level of energy metabolism. Even without severe symptoms of poisoning, fitness can be compromised under harsh environmental conditions, such as cold and wet weather.

  7. The effect of chlorpyrifos on thermogenic capacity of bank voles selected for increased aerobic exercise metabolism.

    PubMed

    Dheyongera, Geoffrey; Grzebyk, Katherine; Rudolf, Agata M; Sadowska, Edyta T; Koteja, Paweł

    2016-04-01

    Agro-chemicals potentially cause adverse effects in non-target organisms. The rate of animal energy metabolism can influence their susceptibility to pesticides by influencing food consumption, biotransformation and elimination rates of toxicants. We used experimental evolution to study the effects of inherent differences in energy metabolism rate and exposure to the organophosphate insecticide, chlorpyrifos (CPF) on thermogenic capacity in a wild rodent, the bank vole (Myodes = Clethrionomys glareolus). The voles were sampled from four replicate lines selected for high swim-induced aerobic metabolism (A) and four unselected control (C) lines. Thermogenic capacity, measured as the maximum cold-induced rate of oxygen consumption (VO2cold), was higher in the A - than C lines, and it decreased after continuous exposure to CPF via food or after a single dose administered via oral gavage, but only when measured shortly after exposure. VO2cold measured 24 h after repeated exposure was not affected. In addition, gavage with a single dose led to decreased food consumption and loss in body mass. Importantly, the adverse effects of CPF did not differ between the selected and control lines. Therefore, exposure to CPF has adverse effects on thermoregulatory performance and energy balance in this species. The effects are short-lived and their magnitude is not associated with the inherent level of energy metabolism. Even without severe symptoms of poisoning, fitness can be compromised under harsh environmental conditions, such as cold and wet weather. PMID:26878110

  8. Juvenile psittacine environmental enrichment.

    PubMed

    Simone-Freilicher, Elisabeth; Rupley, Agnes E

    2015-05-01

    Environmental enrichment is of great import to the emotional, intellectual, and physical development of the juvenile psittacine and their success in the human home environment. Five major types of enrichment include social, occupational, physical, sensory, and nutritional. Occupational enrichment includes exercise and psychological enrichment. Physical enrichment includes the cage and accessories and the external home environment. Sensory enrichment may be visual, auditory, tactile, olfactory, or taste oriented. Nutritional enrichment includes variations in appearance, type, and frequency of diet, and treats, novelty, and foraging. Two phases of the preadult period deserve special enrichment considerations: the development of autonomy and puberty.

  9. Vitamin E supplementation and intense selection increase clonal life span in Paramecium tetraurelia.

    PubMed

    Thomas, J; Nyberg, D

    1988-01-01

    Vitamin E added to standard Cerophyl medium at 0.025 mg/ml significantly increased the mean clonal life span of 32 lines of Paramecium tetraurelia from 52.5 days and 187 fissions to 59.9 days and 209 fissions (p less than .05) when compared to unsupplemented, paired controls. The age-specific death rates increased exponentially. Regression analyses found a significantly lower rate of increasing mortality for the supplemented lines compared to controls. Weekly fission rates of supplemented lines declined linearly; more slowly than controls, but not significantly so. A second experiment tested two higher levels of supplemental vitamin E (0.10 and 1.00 mg/ml). Sublines receiving 1.00 mg/ml of supplemental vitamin E had higher rates of mortality and lower fission rates initially, but the mortality rates increased and the fission rates decreased more slowly than in sublines receiving 0.10 mg/ml supplemental vitamin E, resulting in maximum clonal life spans of 141 days and 330 fissions (1.00 mg/ml sublines), compared to 74 days and 271 fissions (0.10 mg/ml sublines). Survivorship of the last individual cells (nondividing) of each clone followed an exponential decline, with a significant increase in mean survival time for supplemented compared to unsupplemented cells (p less than .05).

  10. Vitamin E supplementation and intense selection increase clonal life span in Paramecium tetraurelia.

    PubMed

    Thomas, J; Nyberg, D

    1988-01-01

    Vitamin E added to standard Cerophyl medium at 0.025 mg/ml significantly increased the mean clonal life span of 32 lines of Paramecium tetraurelia from 52.5 days and 187 fissions to 59.9 days and 209 fissions (p less than .05) when compared to unsupplemented, paired controls. The age-specific death rates increased exponentially. Regression analyses found a significantly lower rate of increasing mortality for the supplemented lines compared to controls. Weekly fission rates of supplemented lines declined linearly; more slowly than controls, but not significantly so. A second experiment tested two higher levels of supplemental vitamin E (0.10 and 1.00 mg/ml). Sublines receiving 1.00 mg/ml of supplemental vitamin E had higher rates of mortality and lower fission rates initially, but the mortality rates increased and the fission rates decreased more slowly than in sublines receiving 0.10 mg/ml supplemental vitamin E, resulting in maximum clonal life spans of 141 days and 330 fissions (1.00 mg/ml sublines), compared to 74 days and 271 fissions (0.10 mg/ml sublines). Survivorship of the last individual cells (nondividing) of each clone followed an exponential decline, with a significant increase in mean survival time for supplemented compared to unsupplemented cells (p less than .05). PMID:3250885

  11. Increased Macular Pigment Optical Density and Visual Acuity following Consumption of a Buttermilk Drink Containing Lutein-Enriched Egg Yolks: A Randomized, Double-Blind, Placebo-Controlled Trial.

    PubMed

    van der Made, Sanne M; Kelly, Elton R; Kijlstra, Aize; Plat, Jogchum; Berendschot, Tos T J M

    2016-01-01

    Purpose. To study the effect of 1-year daily consumption of a dairy drink containing lutein-enriched egg yolks on macular pigment optical density (MPOD) and visual function parameters in elderly subjects with ocular drusen and/or retinal pigment abnormalities. Methods. One hundred and one subjects were recruited to participate in this randomized, double-blind, placebo-controlled parallel intervention trial. Statistical analyses were performed with 46 subjects in the lutein group and 43 in the control group. MPOD, best corrected visual acuity (BCVA, logMAR), and dark adaptation were measured at the start of the study, after 6 months and after 12 months. Plasma lutein and zeaxanthin concentrations were assessed at baseline and at the end of the study. Results. In the lutein group, plasma lutein concentrations increased significantly from 205 ng/mL at baseline to 399 ng/mL after twelve months of intervention. MPOD increased significantly from 0.45 to 0.52 and BCVA improved significantly from -0.04 to -0.09 LogMar. Differences in rod dark adaptation rate between both groups were not significant. Conclusion. Daily consumption of a dairy drink containing lutein-enriched egg yolks for one year improves visual acuity, MPOD, and plasma lutein concentration in elderly subjects with drusen and/or retinal pigment epithelial abnormalities.

  12. Cyclization increases the antimicrobial activity and selectivity of arginine- and tryptophan-containing hexapeptides.

    PubMed

    Dathe, Margitta; Nikolenko, Heike; Klose, Jana; Bienert, Michael

    2004-07-20

    Arginine- and tryptophan-rich motifs have been identified in antimicrobial peptides with various secondary structures. We synthesized a set of linear hexapeptides derived from the sequence AcRRWWRF-NH(2) by substitution of tryptophan (W) by tyrosine (Y) or naphthylalanine (Nal) and by replacement of arginine (R) by lysine (K) to investigate the role of cationic charge and aromatic residues in membrane activity and selectivity. A second set of corresponding head-to-tail cyclic analogues was prepared to analyze the role of conformational constraints. The biological activity of the linear peptides followed the order Nal- > W- > Y-containing compounds and slightly decreased upon R-K substitution. A pronounced activity-improving and bacterial selectivity-enhancing effect was found upon cyclization of the R- and W-bearing parent peptide, whereas the activity-modifying effect of cyclization of Y- and Nal-containing peptides was low. The analysis of the driving forces of peptide interaction with model membranes showed that the activities correlated with the partition coefficients and the depths of peptide insertion into neutral and negatively charged lipid bilayers. Spectroscopic studies, RP-HPLC, and titration calorimetry implied that the combination of cationic and aromatic amino acid composition and conformational rigidity afforded a membrane-active, amphipathic structure with a highly charged face opposed by a cluster of aromatic side chains. However, threshold values of low and high hydrophobicity seemed to exist beyond which the activity-enhancing effect of cyclization was negligible. The results suggest that cyclization of small peptides of an appropriate amino acid composition may serve as a promising strategy in the design of antimicrobial peptides.

  13. Increasing the speed of tumour diagnosis during surgery with selective scanning Raman microscopy

    NASA Astrophysics Data System (ADS)

    Kong, Kenny; Rowlands, Christopher J.; Varma, Sandeep; Perkins, William; Leach, Iain H.; Koloydenko, Alexey A.; Pitiot, Alain; Williams, Hywel C.; Notingher, Ioan

    2014-09-01

    One of the main challenges in cancer surgery is ensuring that all tumour cells are removed during surgery, while sparing as much healthy tissue as possible. Histopathology, the gold-standard technique for cancer diagnosis, is often impractical for intra-operative use because of the time-consuming tissue preparation procedures (sectioning and staining). Raman micro-spectroscopy is a powerful technique that can discriminate between tumours and healthy tissues with high accuracy, based entirely on intrinsic chemical differences. However, raster-scanning Raman micro-spectroscopy is a slow imaging technique that typically requires data acquisition times as long as several days for typical tissue samples obtained during surgery (1 × 1 cm2) - in particular when high signal-to-noise ratio spectra are required to ensure accurate diagnosis. In this paper we present two techniques based on selective sampling Raman micro-spectroscopy that can overcome these limitations. In selective sampling, information regarding the spatial features of the tissue, either measured by an alternative optical technique or estimated in real-time from the Raman spectra, can be used to drastically reduce the number of Raman spectra required for diagnosis. These sampling strategies allowed diagnosis of basal cell carcinoma in skin tissue samples excised during Mohs micrographic surgery faster than frozen section histopathology, and two orders of magnitude faster than previous techniques based on raster-scanning Raman microscopy. Further development of these techniques may help during cancer surgery by providing a fast and objective way for surgeons to ensure the complete removal of tumour cells while sparing as much healthy tissue as possible.

  14. Increased metabolic rate in obese women after ingestion of potassium, magnesium- and phosphate-enriched orange juice or injection of ephedrine.

    PubMed

    Jaedig, S; Henningsen, N C

    1991-06-01

    Thirty-six obese, pre-menopausal women were studied after an overnight fast and randomized to four different regimens of metabolic stimuli: group I (n = 12), 100 ml orange juice with dissolved K- and Mg-phosphates (K, 40 mmol; Mg, 17.5 mmol; HPO4, 35 mmol); group II (n = 8), 100 ml of water with electrolytes as in group I; group III (n = 8), 100 ml of orange juice; group IV (n = 8), injection of ephedrine intravenously, 0.25 mg/kg body weight. The women in groups I, II and III were further stimulated with ephedrine as in group IV and new measurements made. Thirty minutes after the first stimulus VO2, VCO2 and energy expenditure (EE) rose significantly (13.1-16.5 per cent) in groups I and IV only. In groups I and III the blood concentrations of glucose, insulin, and C-peptide rose significantly. After the second stimulus (ephedrine i.v.) no further increase in VO2, VCO2 and EE occurred in group I, but the increases from basal values became significant in group III. In all women at baseline, whole-body potassium was significantly correlated to VO2. Serum-magnesium was negatively correlated to A/I weight (actual/ideal weight). We conclude that the addition of K- and Mg-phosphates to glucose increases the postprandial thermogenesis in obese patients.

  15. Carbon-fiber microelectrodes modified with 4-sulfobenzene have increased sensitivity and selectivity for catecholamines

    PubMed Central

    Hermans, Andre; Seipel, Andrew T.; Miller, Charles E.; Wightman, R. Mark

    2008-01-01

    Elliptical and cylindrical geometries of carbon-fiber microelectrodes were modified by covalent attachment of 4-sulfobenzenediazonium tetrafluoroborate following its electroreduction. Elliptical electrodes fabricated from Thornel P-55 carbon fibers show the highest amount of 4-sulfobenzene attached to the electrode. Fast-scan cyclic voltammetry was used to compare the response to dopamine and other neurochemicals at these modified carbon-fiber microelectrodes. The grafted layer causes an increased sensitivity to dopamine and other positively charged analytes that is due to increased adsorption of analyte in the grafted layer. However, this layer remains permeable to negatively charged compounds. Modified electrodes retain the increased sensitivity for dopamine during measurements in mouse brain tissue. PMID:16489775

  16. Augmenting a Microbial Selective Plugging Technique with Polymer Flooding to Increase the Efficiency of Oil Recovery - A Search for Synergy

    SciTech Connect

    Brown, Lewis R.; Pittman Jr., Charles U.; Lynch, F. Leo; Vadie, A. Alex

    2003-02-10

    The overall objective of this project was to improve the effectiveness of a microbial selective plugging technique of improving oil recovery through the use of polymer floods. More specifically, the intent was to increase the total amount of oil recovered and to reduce the cost per barrel of incremental oil.

  17. Utility of an Error Analysis and Performance Deficit Assessment for Selecting Brief Interventions to Increase Math Fluency

    ERIC Educational Resources Information Center

    Denison, Aaron

    2013-01-01

    The purpose of this study was to examine the utility of a brief assessment for the selection of an effective instruction to increase fluency performance on computation math problems. Participants were four general education third-grade students who performed below the median score on a classwide administered multiple math skills probe. Students…

  18. A survey on breeding strategies and selection objectives for increased feed efficiency and decreased methane emission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The combined effects of world population growth, rising incomes and dietary changes have resulted in an increasing international demand for dairy and meat products. However, livestock can have negative impacts on the environment and the greater awareness of climate change has placed pressure on the ...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella are a leading cause of foodborne illness and can be transmitted through consumption of contaminated poultry; therefore, increasing a flocks’ natural resistance to Salmonella could improve food safety. Previously, we characterized the heterophil-mediated innate immune response of two pare...

  20. Increase in growth, productivity and nutritional status of wheat (Triticum aestivum L. cv. WH-711) and enrichment in soil fertility applied with organic matrix entrapped urea.

    PubMed

    Kumar, Manoj; Bauddh, Kuldeep; Kumar, Sanjeev; Sainger, Manish; Sainger, Poonam A; Singh, Rana P

    2013-01-01

    Field experiments were conducted during two consequent years in semi-arid, subtropical climate of Rohtak district situated in North-West Indian state Haryana to evaluate the effects of eco-friendly organic matrix entrapped urea (OMEU) on wheat (Triticum aestivum L. cv. WH-711). The OMEU prepared in granular form contained cow dung, rice bran (grain cover of Oryza sativa), neem (Azadirachta indica) leaves and clay soil (diameter of particles < 0.002 mm) in 1:1:1:1 ratios and saresh (plant gum of Acacia sp.) as binder entrapping half of the recommended dose of urea. A basal application of organic matrix entrapped urea showed increase in plant growth in terms of fresh and dry weights, root length, root number, leaf number, tillers, plant height earlet number, earlet length and productivity in terms of grain yield and straw yield over free form of urea (FU) and no fertilizer (NF) application. The OMEU increased total soluble proteins, organic N and free ammonium content in the leaves at 45 and 60 days. The nutritional status of wheat grains in OMEU applied plants was almost similar to that observed for FU applied plants. An increase in organic carbon and available phosphorus (P) was observed in OMEU applied plots on harvest whereas pH was slightly decreased over FU applied plots. The microbial population and activity in terms of fungal and bacterial colony count and activities soil dehydrogenase and alkaline phosphatase were significantly higher in OMEU applied plots as compared to the FU applied plots. Our data indicate that OMEU which are low cost, biodegradable and non-toxic can be used to replace the expensive chemical fertilizers for wheat cultivation in semi-arid, subtropical climate. PMID:24006800

  1. Increase in growth, productivity and nutritional status of wheat (Triticum aestivum L. cv. WH-711) and enrichment in soil fertility applied with organic matrix entrapped urea.

    PubMed

    Kumar, Manoj; Bauddh, Kuldeep; Kumar, Sanjeev; Sainger, Manish; Sainger, Poonam A; Singh, Rana P

    2013-01-01

    Field experiments were conducted during two consequent years in semi-arid, subtropical climate of Rohtak district situated in North-West Indian state Haryana to evaluate the effects of eco-friendly organic matrix entrapped urea (OMEU) on wheat (Triticum aestivum L. cv. WH-711). The OMEU prepared in granular form contained cow dung, rice bran (grain cover of Oryza sativa), neem (Azadirachta indica) leaves and clay soil (diameter of particles < 0.002 mm) in 1:1:1:1 ratios and saresh (plant gum of Acacia sp.) as binder entrapping half of the recommended dose of urea. A basal application of organic matrix entrapped urea showed increase in plant growth in terms of fresh and dry weights, root length, root number, leaf number, tillers, plant height earlet number, earlet length and productivity in terms of grain yield and straw yield over free form of urea (FU) and no fertilizer (NF) application. The OMEU increased total soluble proteins, organic N and free ammonium content in the leaves at 45 and 60 days. The nutritional status of wheat grains in OMEU applied plants was almost similar to that observed for FU applied plants. An increase in organic carbon and available phosphorus (P) was observed in OMEU applied plots on harvest whereas pH was slightly decreased over FU applied plots. The microbial population and activity in terms of fungal and bacterial colony count and activities soil dehydrogenase and alkaline phosphatase were significantly higher in OMEU applied plots as compared to the FU applied plots. Our data indicate that OMEU which are low cost, biodegradable and non-toxic can be used to replace the expensive chemical fertilizers for wheat cultivation in semi-arid, subtropical climate.

  2. Increased prediction accuracy in wheat breeding trials using a marker × environment interaction genomic selection model.

    PubMed

    Lopez-Cruz, Marco; Crossa, Jose; Bonnett, David; Dreisigacker, Susanne; Poland, Jesse; Jannink, Jean-Luc; Singh, Ravi P; Autrique, Enrique; de los Campos, Gustavo

    2015-04-01

    Genomic selection (GS) models use genome-wide genetic information to predict genetic values of candidates of selection. Originally, these models were developed without considering genotype × environment interaction(G×E). Several authors have proposed extensions of the single-environment GS model that accommodate G×E using either covariance functions or environmental covariates. In this study, we model G×E using a marker × environment interaction (M×E) GS model; the approach is conceptually simple and can be implemented with existing GS software. We discuss how the model can be implemented by using an explicit regression of phenotypes on markers or using co-variance structures (a genomic best linear unbiased prediction-type model). We used the M×E model to analyze three CIMMYT wheat data sets (W1, W2, and W3), where more than 1000 lines were genotyped using genotyping-by-sequencing and evaluated at CIMMYT's research station in Ciudad Obregon, Mexico, under simulated environmental conditions that covered different irrigation levels, sowing dates and planting systems. We compared the M×E model with a stratified (i.e., within-environment) analysis and with a standard (across-environment) GS model that assumes that effects are constant across environments (i.e., ignoring G×E). The prediction accuracy of the M×E model was substantially greater of that of an across-environment analysis that ignores G×E. Depending on the prediction problem, the M×E model had either similar or greater levels of prediction accuracy than the stratified analyses. The M×E model decomposes marker effects and genomic values into components that are stable across environments (main effects) and others that are environment-specific (interactions). Therefore, in principle, the interaction model could shed light over which variants have effects that are stable across environments and which ones are responsible for G×E. The data set and the scripts required to reproduce the analysis are

  3. Increased Prediction Accuracy in Wheat Breeding Trials Using a Marker × Environment Interaction Genomic Selection Model

    PubMed Central

    Lopez-Cruz, Marco; Crossa, Jose; Bonnett, David; Dreisigacker, Susanne; Poland, Jesse; Jannink, Jean-Luc; Singh, Ravi P.; Autrique, Enrique; de los Campos, Gustavo

    2015-01-01

    Genomic selection (GS) models use genome-wide genetic information to predict genetic values of candidates of selection. Originally, these models were developed without considering genotype × environment interaction(G×E). Several authors have proposed extensions of the single-environment GS model that accommodate G×E using either covariance functions or environmental covariates. In this study, we model G×E using a marker × environment interaction (M×E) GS model; the approach is conceptually simple and can be implemented with existing GS software. We discuss how the model can be implemented by using an explicit regression of phenotypes on markers or using co-variance structures (a genomic best linear unbiased prediction-type model). We used the M×E model to analyze three CIMMYT wheat data sets (W1, W2, and W3), where more than 1000 lines were genotyped using genotyping-by-sequencing and evaluated at CIMMYT’s research station in Ciudad Obregon, Mexico, under simulated environmental conditions that covered different irrigation levels, sowing dates and planting systems. We compared the M×E model with a stratified (i.e., within-environment) analysis and with a standard (across-environment) GS model that assumes that effects are constant across environments (i.e., ignoring G×E). The prediction accuracy of the M×E model was substantially greater of that of an across-environment analysis that ignores G×E. Depending on the prediction problem, the M×E model had either similar or greater levels of prediction accuracy than the stratified analyses. The M×E model decomposes marker effects and genomic values into components that are stable across environments (main effects) and others that are environment-specific (interactions). Therefore, in principle, the interaction model could shed light over which variants have effects that are stable across environments and which ones are responsible for G×E. The data set and the scripts required to reproduce the analysis

  4. Preparation of hydrophilic monolithic capillary column by in situ photo-polymerization of N-vinyl-2-pyrrolidinone and acrylamide for highly selective and sensitive enrichment of N-linked glycopeptides.

    PubMed

    Jiang, Hao; Yuan, Huiming; Qu, Yanyan; Liang, Yu; Jiang, Bo; Wu, Qi; Deng, Nan; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

    2016-01-01

    In this study, a novel kind of amide functionalized hydrophilic monolith was synthesized by the in situ photo-polymerization of N-vinyl-2-pyrrolidinone (NVP), acrylamide (AM), and N, N'-methylenebisacrylamide (MBA) in a UV transparent capillary, and successfully applied for hydrophilic interaction chromatography (HILIC) based enrichment of N-linked glycopeptides. With 2 μg of the tryptic digests of IgG as the sample, after enrichment, 18 glycopeptides could be identified by MALDI-TOF/TOF MS analysis. Furthermore, with the mixture of BSA and IgG digests (10,000:1, m/m) as the sample, 6 N-linked glycopeptides were unambiguously identified after enrichment, indicating the high selectivity and good specificity of such material. Moreover, such a monolithic capillary column was also applied for the N-glycosylation sites profiling of 6 μg protein digests from HeLa cells and 1 μL human serum. In total, 530 and 262 unique N-glycosylated peptides were identified, respectively, corresponding to 282 and 124N-glycoproteins, demonstrating its great potential for the large scale glycoproteomics analysis.

  5. Preparation of hydrophilic monolithic capillary column by in situ photo-polymerization of N-vinyl-2-pyrrolidinone and acrylamide for highly selective and sensitive enrichment of N-linked glycopeptides.

    PubMed

    Jiang, Hao; Yuan, Huiming; Qu, Yanyan; Liang, Yu; Jiang, Bo; Wu, Qi; Deng, Nan; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

    2016-01-01

    In this study, a novel kind of amide functionalized hydrophilic monolith was synthesized by the in situ photo-polymerization of N-vinyl-2-pyrrolidinone (NVP), acrylamide (AM), and N, N'-methylenebisacrylamide (MBA) in a UV transparent capillary, and successfully applied for hydrophilic interaction chromatography (HILIC) based enrichment of N-linked glycopeptides. With 2 μg of the tryptic digests of IgG as the sample, after enrichment, 18 glycopeptides could be identified by MALDI-TOF/TOF MS analysis. Furthermore, with the mixture of BSA and IgG digests (10,000:1, m/m) as the sample, 6 N-linked glycopeptides were unambiguously identified after enrichment, indicating the high selectivity and good specificity of such material. Moreover, such a monolithic capillary column was also applied for the N-glycosylation sites profiling of 6 μg protein digests from HeLa cells and 1 μL human serum. In total, 530 and 262 unique N-glycosylated peptides were identified, respectively, corresponding to 282 and 124N-glycoproteins, demonstrating its great potential for the large scale glycoproteomics analysis. PMID:26695256

  6. Increased quality factor in superconducting microstrip resonators by selective removal of the gold contact layer

    NASA Astrophysics Data System (ADS)

    Schneider, R.; Zaitsev, A. G.; Geerk, J.; Linker, G.; Ratzel, F.; Smithey, R.

    2002-02-01

    We present measurements of the unloaded quality factor of superconducting microstrip resonators at 77 K and 3.86 GHz. The resonators were made of 0.3 μm thick YBa2Cu3O7 films with a transition temperature of 90 K on both sides of ceria-buffered 3 inch sapphire wafers. In particular, we investigated the effect of a 0.3 μm thick gold contact layer on the resonator performance. It was found that the gold layer decreases the quality factor by a factor of almost 5. This result is due to an additional microwave loss in the gold film which can be quantitatively described by the impedance transformation rules for transmission lines. On the basis of the quantitative analysis, we suggest a selective removal of the contact layer by appropriate patterning in order to eliminate the extra loss without deterioration of the low-ohmic galvanic contact to the microwave housing. The experimental results demonstrate the usefulness of the proposed method. Their comparison with the calculated surface current density in the ground plane shows that the contact layer has to be in an area where the current is zero. Furthermore, the results reveal that the surface current density distribution in the ground plane and microstrip depends on the microwave power.

  7. Increasing Oxygen Radicals and Water Temperature Select for Toxic Microcystis sp

    PubMed Central

    Dziallas, Claudia; Grossart, Hans-Peter

    2011-01-01

    Pronounced rises in frequency of toxic cyanobacterial blooms are recently observed worldwide, particularly when temperatures increase. Different strains of cyanobacterial species vary in their potential to produce toxins but driving forces are still obscure. Our study examines effects of hydrogen peroxide on toxic and non-toxic (including a non-toxic mutant) strains of M. aeruginosa. Here we show that hydrogen peroxide diminishes chlorophyll a content and growth of cyanobacteria and that this reduction is significantly lower for toxic than for non-toxic strains. This indicates that microcystins protect from detrimental effects of oxygen radicals. Incubation of toxic and non-toxic strains of M. aeruginosa with other bacteria or without (axenic) at three temperatures (20, 26 and 32°C) reveals a shift toward toxic strains at higher temperatures. In parallel to increases in abundance of toxic (i.e. toxin gene possessing) strains and their actual toxin expression, concentrations of microcystins rise with temperature, when amounts of radicals are expected to be enhanced. Field samples from three continents support the influence of radicals and temperature on toxic potential of M. aeruginosa. Our results imply that global warming will significantly increase toxic potential and toxicity of cyanobacterial blooms which has strong implications for socio-economical assessments of global change. PMID:21980492

  8. Increasing oxygen radicals and water temperature select for toxic Microcystis sp.

    PubMed

    Dziallas, Claudia; Grossart, Hans-Peter

    2011-01-01

    Pronounced rises in frequency of toxic cyanobacterial blooms are recently observed worldwide, particularly when temperatures increase. Different strains of cyanobacterial species vary in their potential to produce toxins but driving forces are still obscure. Our study examines effects of hydrogen peroxide on toxic and non-toxic (including a non-toxic mutant) strains of M. aeruginosa. Here we show that hydrogen peroxide diminishes chlorophyll a content and growth of cyanobacteria and that this reduction is significantly lower for toxic than for non-toxic strains. This indicates that microcystins protect from detrimental effects of oxygen radicals. Incubation of toxic and non-toxic strains of M. aeruginosa with other bacteria or without (axenic) at three temperatures (20, 26 and 32°C) reveals a shift toward toxic strains at higher temperatures. In parallel to increases in abundance of toxic (i.e. toxin gene possessing) strains and their actual toxin expression, concentrations of microcystins rise with temperature, when amounts of radicals are expected to be enhanced. Field samples from three continents support the influence of radicals and temperature on toxic potential of M. aeruginosa. Our results imply that global warming will significantly increase toxic potential and toxicity of cyanobacterial blooms which has strong implications for socio-economical assessments of global change.

  9. Increased consumption of fruit and vegetables and future cancer incidence in selected European countries.

    PubMed

    Soerjomataram, Isabelle; Oomen, Dian; Lemmens, Valery; Oenema, Anke; Benetou, Vassiliki; Trichopoulou, Antonia; Coebergh, Jan Willem; Barendregt, Jan; de Vries, Esther

    2010-09-01

    Cancer is one of the major causes of death in western countries. Fruit and vegetable consumption may reduce the risk of cancers of the oropharynx, oesophagus, lung, stomach and colorectum. We investigated the potential effect of interventions aimed at increasing the intake of fruits and vegetables to the recommended level (500 g/d) on future cancer incidence in Europe. Data on cancer incidence and daily intake of fruit and vegetables were compiled for France, Germany, The Netherlands, Spain and Sweden. We also performed a meta-analysis of European observational studies to arrive at a quantitative estimate on the association between fruit and vegetable intake and cancer risk. Predictions on the future cancer incidence were modelled using PREVENT 3.01. Our study predicted 212,000 fruit- and vegetable-related cancer cases in these countries in 2050, out of which 398 (0.19%) might be prevented if the 500 g/d fruit and vegetable intake were achieved in the aforementioned countries. The largest absolute impact was observed for lung cancer with 257 (out of 136,517) preventable cases if the intervention was successfully implemented. Sweden would benefit the most from intervention to increase fruit and vegetable consumption with a 2% reduction in expected cases. Increasing fruit and vegetable consumption has a small impact on reducing the burden of cancer in Europe. Health impact assessment tools such as PREVENT can provide the basis for decision making in chronic disease prevention.

  10. Do increases in selected fitness parameters affect the aesthetic aspects of classical ballet performance?

    PubMed

    Twitchett, Emily A; Angioi, Manuela; Koutedakis, Yiannis; Wyon, Matthew

    2011-03-01

    Research has indicated that classical ballet dancers tend to have lower fitness levels and increased injury rates compared to other athletes with similar workloads. The aim of the current study was to examine the effects of a specifically tailored fitness training programme on the incidence of injury and the aesthetic quality of performance of classical ballet dancers compared to a control group. Proficiency in performance was evaluated at the beginning and end of the intervention period for both groups through a 4-min dance sequence using previously ratified marking criteria. The intervention group (n = 8) partook in a weekly 1-hr training session that included aerobic interval training, circuit training, and whole body vibration. All dancers' performance proficiency scores increased from pre-intervention testing to post-intervention. The intervention group's overall performance scores demonstrated a significantly greater increase (p = 0.03) than the equivalent for the control group. It was concluded that supplementary fitness training has a positive effect on aspects related to aesthetic dance performance as studied herein; further research is recommended on a larger and more varied sample. Practical applications from this study suggest that supplemental training should be part of a ballet dancer's regime, and minimal intervention time is required to have observable effects.

  11. Negative Mood Increases Selective Attention to Negatively Valenced Body Parts in Female Adolescents with Anorexia Nervosa

    PubMed Central

    Svaldi, Jennifer; Bender, Caroline; Caffier, Detlef; Ivanova, Viliana; Mies, Nina; Fleischhaker, Christian; Tuschen-Caffier, Brunna

    2016-01-01

    Objective Previous research has yielded evidence of increased attentional processing of negatively valenced body parts in women with anorexia nervosa (AN), especially for those with high depressive symptomatology. The present study extended previous research by implementing an experimental mood manipulation. Method In a within-subjects design, female adolescents with AN (n = 12) and an age matched female control group (CG; n = 12) were given a negative and a positive mood induction at a one-week interval. After each mood induction, participants underwent a 3-min mirror exposure, while their eye movements were recorded. Results After the positive mood induction, both AN and CG participants displayed longer and more frequent gazes towards their self-defined most ugly relative to their self-defined most beautiful body part. However, after the negative mood induction, only females with AN were characterized by increased attention to their most ugly compared to their most beautiful body part, while CG participants’ attention distribution was balanced. Furthermore, in the negative (but not in the positive) mood induction condition gaze frequency and duration towards the most ugly body part was significantly stronger in the AN group relative to the CG. Discussion The results emphasize the role of negative mood in the maintenance of pathological information processing of the self-body. This increased body-related negativity-bias during negative mood may lead to the persistence and aggravation of AN patients’ body image disturbance. PMID:27123587

  12. CDF trigger final balance: Offline resolution at low level selections to fight against Tevatron increasing luminosity

    SciTech Connect

    Amerio, S.; /Padua U. /INFN, Padua

    2010-01-01

    The CDF detector at Tevatron collider is at present the most long-lasting high energy physics experiment. Since its first data taking in 1992 it has produced many results of primary importance, such as the discovery of top quark and, more recently, the observations of Bs oscillations and single-top production. None of them would have been possible without a fast and efficient trigger system. Based on a three level architecture, the CDF trigger takes decisions on simple calorimetric and tracking objects and assures both high efficiency on signal events and low dead time. It reduces the data flow rate from 2.53 MHz, the collision rate, to 150 Hz, the current limit on tape writing and is flexible enough to be easily adapted to the continuously growing instantaneous luminosity. In the last years the Tevatron instantaneous luminosity has rapidly increased and is now reaching 4 x 10{sup 32} cm{sup -2} s{sup -1}. The CDF trigger system has been widely upgraded to cope with increasing trigger rates. The upgrade result is online reconstruction of missing transverse energy, jets and tracks with a quality comparable to the offline one. Jet energy and direction can be precisely determined and tracks can be subjected to 3-D reconstruction with good resolution. These upgrades reduce high trigger rates to acceptable levels and have provided invaluable tools to increase the purity of the collected samples. They also represent a helpful experience for LHC experiments where background rates will be much more demanding.

  13. Abrogated thioredoxin system causes increased sensitivity to TNF-α-induced apoptosis via enrichment of p-ERK 1/2 in the nucleus.

    PubMed

    Yoo, Min-Hyuk; Carlson, Bradley A; Gladyshev, Vadim N; Hatfield, Dolph L

    2013-01-01

    Thioredoxin (Trx) and thioredoxin reductase 1 (TR1) are among the major redox regulators in mammalian cells and have a wide variety of roles, including removal of intracellular reactive oxygen species (ROS) and prevention of cell death. Tumor necrosis factor-α (TNF-α) induces cancer cell death. Although ROS have been proposed to participate in this process, the role of the thioredoxin system in TNF-α stimulated cell death remains unclear. We investigated the possibility that the thioredoxin system protects against TNF-α-induced cancer cell death by examining whether TR1/Trx1 status controls TNF-α-induced apoptosis in EMT6 murine breast cancer cells. TR1-deficient cells were more sensitive to TNF-α than control cells. Increased sensitivity to TNF-α was most pronounced in Trx1-deficient cells. TNF-α-induced nuclear localization of phosphorylated ERK 1/2 (p-ERK 1/2) correlated with increased apoptosis in TR1- and Trx1-deficient cells, suggesting a pro-apoptotic role for nuclear p-ERK 1/2 in TNF-α-induced apoptosis. In addition, phosphoinositide 3-kinase (PI3K) inhibition dramatically reduced TNF-α-stimulated apoptosis and nuclear localization of p-ERK 1/2. In contrast, inhibition of ROS, MEK, JNK, or p38 did not significantly alter p-ERK 1/2 localization or apoptosis in TR1- and Trx1-deficient cells compared to control cells. Further, NF-κB p65 localization was not changed in TR1- and Trx1-deficient cells in response to TNF-α relative to control cells. Our data suggest that the thioredoxin system plays a critical role in protecting against TNF-α-induced apoptosis by regulating the levels of nuclear p-ERK 1/2 in a PI3K-dependent manner.

  14. Prolonged applied potential to anode facilitate selective enrichment of bio-electrochemically active Proteobacteria for mediating electron transfer: microbial dynamics and bio-catalytic analysis.

    PubMed

    Kannaiah Goud, R; Mohan, S Venkata

    2013-06-01

    Prolonged application of poised potential to anode was evaluated to understand the influence of applied potentials [500 mV (E500); 1000 mV (E1000); 2000 mV (E2000)] on bio-electrogenic activity of microbial fuel cell (MFC) and the resulting dynamics in microbial community in comparison to control operation. E1000 system documented higher electrogenic activity (309 mW/m(2)) followed by E500 (143 mW/m(2)), E2000 (112 mW/m(2)) and control (65 mW/m(2)) operations. The improved power output at optimum applied potential (1000mV) might be attributed to the enrichment of electrochemically active bacteria majorly belonging to the phylum Proteobacteria with less extent of Firmicutes which helped in effective electron (mediated) transfer through release of exogenous shuttlers. Improved bio-electrogenic activity due to enrichment at 1000mV applied potential also correlated well with the observed cyctochrome-c peaks on the voltamatogram, lower ion ohmic losses and bio-electro kinetic analysis. Electric-shock at higher applied potential (E2000) resulted in the survival of less number of microbial species leading to lower electrogenesis.

  15. /sup 13/C nuclear magnetic resonance studies of the biosynthesis by Microbacterium ammoniaphilum of L-glutamate selectively enriched with carbon-13

    SciTech Connect

    Walker, T.E.; Han, C.H.; Kollman, V.H.; London, R.E.; Matwiyoff, N.A.

    1982-02-10

    /sup 13/C NMR of isotopically enriched metabolites has been used to study the metabolism of Microbacterium ammoniaphilum, a bacterium which excretes large quantities of L-glutamic acid into the medium. Biosynthesis from 90% (1-/sup 13/C) glucose results in relatively high specificity of the label, with (2,4-/sup 13/C/sub 2/) glutamate as the major product. The predominant biosynthetic pathway for synthesis of glutamate from glucose was determined to be the Embden Meyerhof glycolytic pathway followed by P-enolpyruvate carboxylase and the first third of the Krebs cycle. Different metabolic pathways are associated with different correlations in the enrichment of the carbons, reflected in the spectrum as different /sup 13/C-/sup 13/C scalar multiplet intensities. Hence, intensity and /sup 13/C-/sup 13/C multiplet analysis allows quantitation of the pathways involved. Although blockage of the Krebs cycle at the ..cap alpha..-ketoglutarate dehydrogenase step is the basis for the accumulation of glutamate, significant Krebs cycle activity was found in glucose grown cells, and extensive Krebs cycle activity in cells metabolizing (1-/sup 13/C) acetate. In addition to the observation of the expected metabolites, the disaccharide ..cap alpha..,..cap alpha..-trehalose and ..cap alpha..,..beta..-glucosylamine were identified from the /sup 13/C NMR spectra.

  16. Selective Heart Rate Reduction With Ivabradine Increases Central Blood Pressure in Stable Coronary Artery Disease.

    PubMed

    Rimoldi, Stefano F; Messerli, Franz H; Cerny, David; Gloekler, Steffen; Traupe, Tobias; Laurent, Stéphane; Seiler, Christian

    2016-06-01

    Heart rate (HR) lowering by β-blockade was shown to be beneficial after myocardial infarction. In contrast, HR lowering with ivabradine was found to confer no benefits in 2 prospective randomized trials in patients with coronary artery disease. We hypothesized that this inefficacy could be in part related to ivabradine's effect on central (aortic) pressure. Our study included 46 patients with chronic stable coronary artery disease who were randomly allocated to placebo (n=23) or ivabradine (n=23) in a single-blinded fashion for 6 months. Concomitant baseline medication was continued unchanged throughout the study except for β-blockers, which were stopped during the study period. Central blood pressure and stroke volume were measured directly by left heart catheterization at baseline and after 6 months. For the determination of resting HR at baseline and at follow-up, 24-hour ECG monitoring was performed. Patients on ivabradine showed an increase of 11 mm Hg in central systolic pressure from 129±22 mm Hg to 140±26 mm Hg (P=0.02) and in stroke volume by 86±21.8 to 107.2±30.0 mL (P=0.002). In the placebo group, central systolic pressure and stroke volume remained unchanged. Estimates of myocardial oxygen consumption (HR×systolic pressure and time-tension index) remained unchanged with ivabradine.The decrease in HR from baseline to follow-up correlated with the concomitant increase in central systolic pressure (r=-0.41, P=0.009) and in stroke volume (r=-0.61, P<0.001). In conclusion, the decrease in HR with ivabradine was associated with an increase in central systolic pressure, which may have antagonized possible benefits of HR lowering in coronary artery disease patients. CLINICAL TRIALSURL: http://www.clinicaltrials.gov. Unique identifier NCT01039389. PMID:27091900

  17. Breeding and Selection of New Switchgrass Varieties for Increased Biomass Production

    SciTech Connect

    Taliaferro, C.M.

    2003-05-27

    Switchgrass breeding and genetics research was conducted from 1992-2002 at the Oklahoma State University as part of the national DOE-Bioenergy Feedstock Development Program (BFDP) effort to develop the species as a bioenergy feedstock crop. The fundamental objective of the program was to implement and conduct a breeding program to increase biomass yield capability in switchgrass and develop cultivars for the central and southern United States. Supporting research objectives included: (1) switchgrass germplasm collection, characterization, and enhancement; (2) elucidation of cytogenetic and breeding behavior; and (3) identification of best breeding procedures.

  18. Enrichment and individual differences affect welfare indicators in squirrel monkeys (Saimiri sciureus).

    PubMed

    Izzo, Genevieve N; Bashaw, Meredith J; Campbell, John B

    2011-08-01

    Enrichment aims to improve captive animals' welfare by enhancing their environments. Two of the struggles associated with measuring welfare are identifying when animals' needs are being met or surpassed and identifying how individual differences play a role in these outcomes. Using a group of related Guyanese squirrel monkeys, we studied changes in five welfare indicators under different environmental conditions. Manipulating food presentation, walkways, and toys, we created five enrichment levels ranging from just above USDA standards to considerably more complex than the animals' normal housing. At the end of each level, a novelty test was performed in which an unfamiliar woman entered the enclosure and offered food. Changes in behavior as a function of enrichment condition were analyzed using a repeated-measures MANOVA. Compared to baseline, less enrichment consistently increased negative welfare indicators (abnormal behavior, aggression, and negative responses to the novelty test), while more enrichment sometimes decreased these indicators. Positive welfare indicators were less consistently related to enrichment, but positive response to the novelty test did increase somewhat in the most enriched condition. Across conditions, rank correlations revealed that individuals had highly consistent individual differences in positive responses to novelty and somewhat consistent individual differences in rates of aggression. The goal of the enrichment and the species, sex, and individual animals to be enriched should be considered when selecting a welfare indicator, and facilities measuring animal welfare should study changes in the behavior of specific individuals to control for individual differences.

  19. Recurrent selection for wider seedling leaves increases early biomass and leaf area in wheat (Triticum aestivum L.).

    PubMed

    Zhang, L; Richards, R A; Condon, A G; Liu, D C; Rebetzke, G J

    2015-03-01

    The breeding of wheat with greater early vigour has potential to increase water- and nutrient-use efficiency, as well as to improve weed competitiveness to raise crop yields profitably. Given that wheat is inherently conservative in its early growth, a sustained breeding effort was initiated to increase genetically seedling leaf area in developing novel high vigour germplasm. A recurrent selection programme was initiated by intercrossing a genetically diverse set of 28 vigorous wheat lines identified globally. These were intercrossed at random and S1:2 progeny with the largest leaf 1 and 2 widths were intermated to develop new populations for assessment of early growth. This procedure was repeated for up to 60 segregating families per cycle across six cycles over 15 years. Thirty random S1:2 progeny were retained from each cycle and seed-increased together to produce seed for early vigour assessment in multiple sowings. The most vigorous wheat seedlings were identified in later cycles, with some lines producing more than double the leaf area and biomass of elite commercial wheat varieties. Phenotypic selection for greater leaf width was associated with a realized significant (P<0.01) linear increase per seedling of 0.41 mm per cycle (+7.1%) for mean leaf width, and correlated linear increases in total leaf area and biomass of 4.48 cm(2) per cycle (+10.3%) and 10.8 mg per cycle (+5.3%), respectively. Genetic gains in widths of leaves 2 (+8.4%) and 3 (+11.5%) were significantly (P<0.01) greater than for leaf 1 (+5.3%). Selection for greater leaf width was associated with linear increases in coleoptile tiller leaf area, small curvilinear increases in leaf 1 length, and reductions in numbers of leaves and mainstem tillers. Genetic variances were large and heritabilities high for leaf width and total leaf area in each cycle, but reduced linearly in size with selection across cycles. Coupling diverse germplasm with a simple, inexpensive, and repeatable selection process

  20. Improved detection of extended spectrum beta-lactamase (ESBL)-producing Escherichia coli in input and output samples of German biogas plants by a selective pre-enrichment procedure.

    PubMed

    Schauss, Thorsten; Glaeser, Stefanie P; Gütschow, Alexandra; Dott, Wolfgang; Kämpfer, Peter

    2015-01-01

    The presence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli was investigated in input (manure from livestock husbandry) and output samples of six German biogas plants in 2012 (one sampling per biogas plant) and two German biogas plants investigated in an annual cycle four times in 2013/2014. ESBL-producing Escherichia coli were cultured by direct plating on CHROMagar ESBL from input samples in the range of 100 to 104 colony forming units (CFU) per g dry weight but not from output sample. This initially indicated a complete elimination of ESBL-producing E. coli by the biogas plant process. Detected non target bacteria were assigned to the genera Acinetobacter, Pseudomonas, Bordetella, Achromobacter, Castellaniella, and Ochrobactrum. A selective pre-enrichment procedure increased the detection efficiency of ESBL-producing E. coli in input samples and enabled the detection in five of eight analyzed output samples. In total 119 ESBL-producing E. coli were isolated from input and 46 from output samples. Most of the E. coli isolates carried CTX-M-type and/or TEM-type beta lactamases (94%), few SHV-type beta lactamase (6%). Sixty-four blaCTX-M genes were characterized more detailed and assigned mainly to CTX-M-groups 1 (85%) and 9 (13%), and one to group 2. Phylogenetic grouping of 80 E. coli isolates showed that most were assigned to group A (71%) and B1 (27%), only one to group D (2%). Genomic fingerprinting and multilocus sequence typing (MLST) showed a high clonal diversity with 41 BOX-types and 19 ST-types. The two most common ST-types were ST410 and ST1210. Antimicrobial susceptibility testing of 46 selected ESBL-producing E. coli revealed that several isolates were additionally resistant to other veterinary relevant antibiotics and some grew on CHROMagar STEC but shiga-like toxine (SLT) genes were not detected. Resistance to carbapenems was not detected. In summary the study showed for the first time the presence of ESBL-producing E. coli in

  1. Improved detection of extended spectrum beta-lactamase (ESBL)-producing Escherichia coli in input and output samples of German biogas plants by a selective pre-enrichment procedure.

    PubMed

    Schauss, Thorsten; Glaeser, Stefanie P; Gütschow, Alexandra; Dott, Wolfgang; Kämpfer, Peter

    2015-01-01

    The presence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli was investigated in input (manure from livestock husbandry) and output samples of six German biogas plants in 2012 (one sampling per biogas plant) and two German biogas plants investigated in an annual cycle four times in 2013/2014. ESBL-producing Escherichia coli were cultured by direct plating on CHROMagar ESBL from input samples in the range of 100 to 104 colony forming units (CFU) per g dry weight but not from output sample. This initially indicated a complete elimination of ESBL-producing E. coli by the biogas plant process. Detected non target bacteria were assigned to the genera Acinetobacter, Pseudomonas, Bordetella, Achromobacter, Castellaniella, and Ochrobactrum. A selective pre-enrichment procedure increased the detection efficiency of ESBL-producing E. coli in input samples and enabled the detection in five of eight analyzed output samples. In total 119 ESBL-producing E. coli were isolated from input and 46 from output samples. Most of the E. coli isolates carried CTX-M-type and/or TEM-type beta lactamases (94%), few SHV-type beta lactamase (6%). Sixty-four blaCTX-M genes were characterized more detailed and assigned mainly to CTX-M-groups 1 (85%) and 9 (13%), and one to group 2. Phylogenetic grouping of 80 E. coli isolates showed that most were assigned to group A (71%) and B1 (27%), only one to group D (2%). Genomic fingerprinting and multilocus sequence typing (MLST) showed a high clonal diversity with 41 BOX-types and 19 ST-types. The two most common ST-types were ST410 and ST1210. Antimicrobial susceptibility testing of 46 selected ESBL-producing E. coli revealed that several isolates were additionally resistant to other veterinary relevant antibiotics and some grew on CHROMagar STEC but shiga-like toxine (SLT) genes were not detected. Resistance to carbapenems was not detected. In summary the study showed for the first time the presence of ESBL-producing E. coli in

  2. Improved Detection of Extended Spectrum Beta-Lactamase (ESBL)-Producing Escherichia coli in Input and Output Samples of German Biogas Plants by a Selective Pre-Enrichment Procedure

    PubMed Central

    Schauss, Thorsten; Glaeser, Stefanie P.; Gütschow, Alexandra; Dott, Wolfgang; Kämpfer, Peter

    2015-01-01

    The presence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli was investigated in input (manure from livestock husbandry) and output samples of six German biogas plants in 2012 (one sampling per biogas plant) and two German biogas plants investigated in an annual cycle four times in 2013/2014. ESBL-producing Escherichia coli were cultured by direct plating on CHROMagar ESBL from input samples in the range of 100 to 104 colony forming units (CFU) per g dry weight but not from output sample. This initially indicated a complete elimination of ESBL-producing E. coli by the biogas plant process. Detected non target bacteria were assigned to the genera Acinetobacter, Pseudomonas, Bordetella, Achromobacter, Castellaniella, and Ochrobactrum. A selective pre-enrichment procedure increased the detection efficiency of ESBL-producing E. coli in input samples and enabled the detection in five of eight analyzed output samples. In total 119 ESBL-producing E. coli were isolated from input and 46 from output samples. Most of the E. coli isolates carried CTX-M-type and/or TEM-type beta lactamases (94%), few SHV-type beta lactamase (6%). Sixty-four blaCTX-M genes were characterized more detailed and assigned mainly to CTX-M-groups 1 (85%) and 9 (13%), and one to group 2. Phylogenetic grouping of 80 E. coli isolates showed that most were assigned to group A (71%) and B1 (27%), only one to group D (2%). Genomic fingerprinting and multilocus sequence typing (MLST) showed a high clonal diversity with 41 BOX-types and 19 ST-types. The two most common ST-types were ST410 and ST1210. Antimicrobial susceptibility testing of 46 selected ESBL-producing E. coli revealed that several isolates were additionally resistant to other veterinary relevant antibiotics and some grew on CHROMagar STEC but shiga-like toxine (SLT) genes were not detected. Resistance to carbapenems was not detected. In summary the study showed for the first time the presence of ESBL-producing E. coli in

  3. Scaling of metabolism in Helix aspersa snails: changes through ontogeny and response to selection for increased size.

    PubMed

    Czarnołeski, Marcin; Kozłowski, Jan; Dumiot, Guillaume; Bonnet, Jean-Claude; Mallard, Jacques; Dupont-Nivet, Mathilde

    2008-02-01

    Though many are convinced otherwise, variability of the size-scaling of metabolism is widespread in nature, and the factors driving that remain unknown. Here we test a hypothesis that the increased expenditure associated with faster growth increases metabolic scaling. We compare metabolic scaling in the fast- and slow-growth phases of ontogeny of Helix aspersa snails artificially selected or not selected for increased adult size. The selected line evolved larger egg and adult sizes and a faster size-specific growth rate, without a change in the developmental rate. Both lines had comparable food consumption but the selected snails grew more efficiently and had lower metabolism early in ontogeny. Attainment of lower metabolism was accompanied by decreased shell production, indicating that the increased growth was fuelled partly at the expense of shell production. As predicted, the scaling of oxygen consumption with body mass was isometric or nearly isometric in the fast-growing (early) ontogenetic stage, and it became negatively allometric in the slow-growing (late) stage; metabolic scaling tended to be steeper in selected (fast-growing) than in control (slow-growing) snails; this difference disappeared later in ontogeny. Differences in metabolic scaling were not related to shifts in the scaling of metabolically inert shell. Our results support the view that changes in metabolic scaling through ontogeny and the variability of metabolic scaling between organisms can be affected by differential growth rates. We stress that future approaches to this phenomenon should consider the metabolic effects of cell size changes which underlie shifts in the growth pattern.

  4. Consuming a buttermilk drink containing lutein-enriched egg yolk daily for 1 year increased plasma lutein but did not affect serum lipid or lipoprotein concentrations in adults with early signs of age-related macular degeneration.

    PubMed

    van der Made, Sanne M; Kelly, Elton R; Berendschot, Tos T J M; Kijlstra, Aize; Lütjohann, Dieter; Plat, Jogchum

    2014-09-01

    Dietary lutein intake is postulated to interfere with the development of age-related macular degeneration (AMD). Because egg yolk-derived lutein has a high bioavailability, long-term consumption of lutein-enriched eggs might be effective in preventing AMD development, but alternatively might increase cardiovascular disease risk. Here, we report the effect of 1-y daily consumption of a buttermilk drink containing 1.5 lutein-rich egg yolks on serum lipid and lipoprotein and plasma lutein concentrations. Additionally, subgroups that could potentially benefit the most from the intervention were identified. Men and women who had early signs of AMD in at least 1 eye, but were otherwise healthy, participated in a 1-y randomized, placebo-controlled parallel intervention trial. At the start of the study, 101 participants were included: 52 in the experimental (Egg) group and 49 in the control (Con) group. Final analyses were performed with 45 participants in the Egg group and 43 participants in the Con group. As expected, the increase in plasma lutein concentrations in the Egg group was 83% higher than that in the Con group (P < 0.001). Changes in serum total, HDL, and LDL cholesterol, as well as the ratio of total cholesterol to HDL cholesterol, were not different between the 2 groups. Interestingly, participants classified as cholesterol absorbers had higher serum HDL cholesterol concentrations than participants classified as cholesterol synthesizers or participants with average campesterol-to-lathosterol ratios (P < 0.05) at baseline. In addition, cholesterol absorbers had a 229% higher increase in plasma lutein concentrations than participants who were classified as having an average campesterol-to-lathosterol ratio upon consumption of the lutein-enriched egg yolk drink (P < 0.05). Moreover, the change in serum HDL cholesterol upon consumption was significantly different between these 3 groups (P < 0.05). We suggest that cholesterol absorbers particularly might benefit

  5. Increase of sample load without peak deterioration by careful selection of electrolyte in capillary zone electrophoresis.

    PubMed

    Andersson, E K Margareta; Hägglund, I

    2002-04-12

    In this study it is demonstrated that much higher concentrations of bases dissolved in water can be injected in capillary zone electrophoresis without causing peak deterioration, e.g., peak splitting, if it is the co-ion that buffers instead of the counter-ion. Those findings can be utilised to control peak shapes and in this way an increase in the sample load and indirectly a decrease in the detection limits of impurities in the sample can be obtained. Good results were obtained with 4-aminobutyric and 6-aminocaproic acids as buffering co-ions. Another possibility evaluated successfully was that of using a dibasic acid, malic acid or succinic acid. With an electrolyte containing both succinic acid and 6-aminocaproic acid at pH 4.5, it was possible to load at least 10-20 times more of the test substances imidazole, creatinine or 2-aminopyrimidine dissolved in water than with an electrolyte at the same pH containing acetic acid and tris(hydroxymethyl)aminomethane. PMID:12058936

  6. Selected contribution: redistribution of pulmonary perfusion during weightlessness and increased gravity

    NASA Technical Reports Server (NTRS)

    Glenny, R. W.; Lamm, W. J.; Bernard, S. L.; An, D.; Chornuk, M.; Pool, S. L.; Wagner, W. W. Jr; Hlastala, M. P.; Robertson, H. T.

    2000-01-01

    To compare the relative contributions of gravity and vascular structure to the distribution of pulmonary blood flow, we flew with pigs on the National Aeronautics and Space Administration KC-135 aircraft. A series of parabolas created alternating weightlessness and 1.8-G conditions. Fluorescent microspheres of varying colors were injected into the pulmonary circulation to mark regional blood flow during different postural and gravitational conditions. The lungs were subsequently removed, air dried, and sectioned into approximately 2 cm(3) pieces. Flow to each piece was determined for the different conditions. Perfusion heterogeneity did not change significantly during weightlessness compared with normal and increased gravitational forces. Regional blood flow to each lung piece changed little despite alterations in posture and gravitational forces. With the use of multiple stepwise linear regression, the contributions of gravity and vascular structure to regional perfusion were separated. We conclude that both gravity and the geometry of the pulmonary vascular tree influence regional pulmonary blood flow. However, the structure of the vascular tree is the primary determinant of regional perfusion in these animals.

  7. Selective enrichment of sulfides, thiols and methylthiophosphates from water samples on metal-loaded cation-exchange materials for gas chromatographic analysis.

    PubMed

    Beiner, K; Popp, P; Wennrich, R

    2002-08-30

    The suitability of using metal-loaded sorbents for solid-phase extraction to enrich organic sulfur compounds from water samples was studied. To test the retention behavior of a number of sulfides, thiols and methylthiophosphates, a cation-exchanger was loaded with various metal ions. The elution behavior of sulfur compounds was investigated with different solvents. A combination of Pb2+-modified cation-exchanger as sorbent and CS2 (1%, v/v) in toluene proved to be the most suitable approach for the given problem. Using GC with a pulsed flame photometric detector yielded detection limits of between 0.6 and 2.9 microg/l. The results showed good reproducibility with relative standard deviations of 2-11%. PMID:12236501

  8. Designed synthesis of carbon-functional magnetic graphene mesoporous silica materials using polydopamine as carbon precursor for the selective enrichment of N-linked glycan.

    PubMed

    Sun, Nianrong; Yao, Jizong; Deng, Chunhui

    2016-02-01

    Glycosylation, which has been confirmed to be associated with many diseases, is an important protein post-translation modification. Taking into account the low abundant of glycan, the purification of complex biological samples is considered to be very significant before mass spectrometry detection. In this work, carbon-functionalized magnetic graphene /mesoporous silica materials (C-Mag G@mSiO2 materials) with high content of carbon were designed and synthesized by using polydopamine as carbon precursor. Taking advantage of the special interaction between carbon and glycan, C-Mag G@mSiO2 materials were successfully applied to enrich N-linked glycans in different complex samples, such as standard glycoprotein digestion, the mixture of standard glycoprotein digestion, glycoprotein and non-glycoprotein, and human serum.

  9. Mating increases neuronal tyrosine hydroxylase expression and selectively gates transmission of male chemosensory information in female mice.

    PubMed

    Matthews, Gillian A; Patel, Ronak; Walsh, Alison; Davies, Owain; Martínez-Ricós, Joana; Brennan, Peter A

    2013-01-01

    Exposure to chemosensory signals from unfamiliar males can terminate pregnancy in recently mated female mice. The number of tyrosine hydroxylase-positive neurons in the main olfactory bulb has been found to increase following mating and has been implicated in preventing male-induced pregnancy block during the post-implantation period. In contrast, pre-implantation pregnancy block is mediated by the vomeronasal system, and is thought to be prevented by selective inhibition of the mate's pregnancy blocking chemosignals, at the level of the accessory olfactory bulb. The objectives of this study were firstly to identify the level of the vomeronasal pathway at which selective inhibition of the mate's pregnancy blocking chemosignals occurs. Secondly, to determine whether a post-mating increase in tyrosine hydroxylase-positive neurons is observed in the vomeronasal system, which could play a role in preventing pre-implantation pregnancy block. Immunohistochemical staining revealed that mating induced an increase in tyrosine-hydroxylase positive neurons in the arcuate hypothalamus of BALB/c females, and suppressed c-Fos expression in these neurons in response to mating male chemosignals. This selective suppression of c-Fos response to mating male chemosignals was not apparent at earlier levels of the pregnancy-blocking neural pathway in the accessory olfactory bulb or corticomedial amygdala. Immunohistochemical staining revealed an increase in the number of tyrosine hydroxylase-positive neurons in the accessory olfactory bulb of BALB/c female mice following mating. However, increased dopamine-mediated inhibition in the accessory olfactory bulb is unlikely to account for the prevention of pregnancy block to the mating male, as tyrosine hydroxylase expression did not increase in females of the C57BL/6 strain, which show normal mate recognition. These findings reveal an association of mating with increased dopaminergic modulation in the pregnancy block pathway and support the

  10. Gene set enrichment analysis.

    PubMed

    Tilford, Charles A; Siemers, Nathan O

    2009-01-01

    Set enrichment analytical methods have become commonplace tools applied to the analysis and interpretation of biological data. The statistical techniques are used to identify categorical biases within lists of genes, proteins, or metabolites. The goal is to discover the shared functions or properties of the biological items represented within the lists. Application of these methods can provide great biological insight, including the discovery of participation in the same biological activity or pathway, shared interacting genes or regulators, common cellular compartmentalization, or association with disease. The methods require ordered or unordered lists of biological items as input, understanding of the reference set from which the lists were selected, categorical classifiers describing the items, and a statistical algorithm to assess bias of each classifier. Due to the complexity of most algorithms and the number of calculations performed, computer software is almost always used for execution of the algorithm, as well as for presentation of the results. This chapter will provide an overview of the statistical methods used to perform an enrichment analysis. Guidelines for assembly of the requisite information will be presented, with a focus on careful definition of the sets used by the statistical algorithms. The need for multiple test correction when working with large libraries of classifiers is emphasized, and we outline several options for performing the corrections. Finally, interpreting the results of such analysis will be discussed along with examples of recent research utilizing the techniques.

  11. Preference assessments in the zoo: Keeper and staff predictions of enrichment preferences across species.

    PubMed

    Mehrkam, Lindsay R; Dorey, Nicole R

    2015-01-01

    Environmental enrichment is widely used in the management of zoo animals, and is an essential strategy for increasing the behavioral welfare of these populations. It may be difficult, however, to identify potentially effective enrichment strategies that are also cost-effective and readily available. An animal's preference for a potential enrichment item may be a reliable predictor of whether that individual will reliably interact with that item, and subsequently enable staff to evaluate the effects of that enrichment strategy. The aim of the present study was to assess the utility of preference assessments for identifying potential enrichment items across six different species--each representing a different taxonomic group. In addition, we evaluated the agreement between zoo personnel's predictions of animals' enrichment preferences and stimuli selected via a preference assessment. Five out of six species (nine out of 11 individuals) exhibited clear, systematic preferences for specific stimuli. Similarities in enrichment preferences were observed among all individuals of primates, whereas individuals within ungulate and avian species displayed individual differences in enrichment preferences. Overall, zoo personnel, regardless of experience level, were significantly more accurate at predicting least-preferred stimuli than most-preferred stimuli across species, and tended to make the same predictions for all individuals within a species. Preference assessments may therefore be a useful, efficient husbandry strategy for identifying viable enrichment items at both the individual and species levels. PMID:26179195

  12. Preference assessments in the zoo: Keeper and staff predictions of enrichment preferences across species.

    PubMed

    Mehrkam, Lindsay R; Dorey, Nicole R

    2015-01-01

    Environmental enrichment is widely used in the management of zoo animals, and is an essential strategy for increasing the behavioral welfare of these populations. It may be difficult, however, to identify potentially effective enrichment strategies that are also cost-effective and readily available. An animal's preference for a potential enrichment item may be a reliable predictor of whether that individual will reliably interact with that item, and subsequently enable staff to evaluate the effects of that enrichment strategy. The aim of the present study was to assess the utility of preference assessments for identifying potential enrichment items across six different species--each representing a different taxonomic group. In addition, we evaluated the agreement between zoo personnel's predictions of animals' enrichment preferences and stimuli selected via a preference assessment. Five out of six species (nine out of 11 individuals) exhibited clear, systematic preferences for specific stimuli. Similarities in enrichment preferences were observed among all individuals of primates, whereas individuals within ungulate and avian species displayed individual differences in enrichment preferences. Overall, zoo personnel, regardless of experience level, were significantly more accurate at predicting least-preferred stimuli than most-preferred stimuli across species, and tended to make the same predictions for all individuals within a species. Preference assessments may therefore be a useful, efficient husbandry strategy for identifying viable enrichment items at both the individual and species levels.

  13. Environmental enrichment induces neuroplastic changes in middle age female Balb/c mice and increases the hippocampal levels of BDNF, p-Akt and p-MAPK1/2.

    PubMed

    Ramírez-Rodríguez, G; Ocaña-Fernández, M A; Vega-Rivera, N M; Torres-Pérez, O M; Gómez-Sánchez, A; Estrada-Camarena, E; Ortiz-López, L

    2014-02-28

    Hippocampus is one of the brain regions in which neuroplastic changes occur. Paradigms such as environmental enrichment (ENR) have been used to prevent or delay the neuroplastic changes of the hippocampus during aging. Here, we investigated the beneficial effects of ENR on dendritic spines and hippocampal neurogenesis in middle age Balb/c mice. ENR increased the number of dendritic spines, cell survival, and intermediate stages of the hippocampal neurodevelopment process. Also, ENR alters the distribution of cells involved in the neurogenic process along the dorsal-ventral dentate gyrus. In addition, ENR increased the proportion of cells with more mature dendritic morphology and net hippocampal neurogenesis. Whole-hippocampus protein extracts revealed that ENR increases the levels of BDNF, phospho-Akt and phospho-MAPK1/2, suggesting that the positive effects of ENR on neuroplasticity in middle age Balb/c mice involve the participation of these key-signaling proteins. Our results suggest that ENR is a relevant strategy to prevent neuroplastic decline by increasing the formation of both dendritic spines and new neurons in the hippocampus during middle age.

  14. An exotic invasive plant selects for increased competitive tolerance, but not competitive suppression, in a native grass.

    PubMed

    Fletcher, Rebecca A; Callaway, Ragan M; Atwater, Daniel Z

    2016-06-01

    Exotic invasive plants can exert strong selective pressure for increased competitive ability in native plants. There are two fundamental components of competitive ability: suppression and tolerance, and the current paradigm that these components have equal influences on a species' overall competitive ability has been recently questioned. If these components do not have equal influences on overall ability, then selection on competitive tolerance and suppression may be disproportionate. We used naturally invaded communities to study the effects of selection caused by an invasive forb, Centaurea stoebe, on a native grass, Pseudoroegneria spicata. P. spicata plants were harvested from within dense C. stoebe patches and from nearby uninvaded areas, divided clonally into replicates, then transplanted into a common garden where they grew alone or competed with C. stoebe. We found that P. spicata plants collected from within C. stoebe patches were significantly more tolerant of competition with C. stoebe than P. spicata plants collected from uninvaded areas, but plants from inside invaded patches were not superior at suppressing C. stoebe. These results are consistent with the hypothesis that strong competitors may select for tolerance to competition more than for the ability to suppress neighbors. This has important implications for how native plant communities may respond to invasion over time, and how invasive and native species may ultimately coexist. PMID:26897605

  15. Selective increase of in vivo firing frequencies in DA SN neurons after proteasome inhibition in the ventral midbrain.

    PubMed

    Subramaniam, Mahalakshmi; Kern, Beatrice; Vogel, Simone; Klose, Verena; Schneider, Gaby; Roeper, Jochen

    2014-09-01

    The impairment of protein degradation via the ubiquitin-proteasome system (UPS) is present in sporadic Parkinson's disease (PD), and might play a key role in selective degeneration of vulnerable dopamine (DA) neurons in the substantia nigra pars compacta (SN). Further evidence for a causal role of dysfunctional UPS in familial PD comes from mutations in parkin, which results in a loss of function of an E3-ubiquitin-ligase. In a mouse model, genetic inactivation of an essential component of the 26S proteasome lead to widespread neuronal degeneration including DA midbrain neurons and the formation of alpha-synuclein-positive inclusion bodies, another hallmark of PD. Studies using pharmacological UPS inhibition in vivo had more mixed results, varying from extensive degeneration to no loss of DA SN neurons. However, it is currently unknown whether UPS impairment will affect the neurophysiological functions of DA midbrain neurons. To answer this question, we infused a selective proteasome inhibitor into the ventral midbrain in vivo and recorded single DA midbrain neurons 2 weeks after the proteasome challenge. We found a selective increase in the mean in vivo firing frequencies of identified DA SN neurons in anesthetized mice, while those in the ventral tegmental area (VTA) were unaffected. Our results demonstrate that a single-hit UPS inhibition is sufficient to induce a stable and selective hyperexcitability phenotype in surviving DA SN neurons in vivo. This might imply that UPS dysfunction sensitizes DA SN neurons by enhancing 'stressful pacemaking'.

  16. The value of enrichment to reintroduction success.

    PubMed

    Reading, Richard P; Miller, Brian; Shepherdson, David

    2013-01-01

    Reintroduction attempts have faced low, albeit improving, success rates, especially for threatened and endangered species reintroduced from captivity to the wild. This is not only a concern for conservation, as the low success of reintroduction also implies an animal welfare issue for the individuals concerned. Success rates are particularly low for species that live in complex social structures, require greater training during development, and exhibit higher levels of intelligence. Aside from mitigating the original cause of a species extirpation from an area, behavior factors arguably represent the most important aspect influencing an animal's survival following reintroduction. Indeed, we previously recommended using behavioral indicators for determining relative reintroduction success, especially as practitioners develop and compare protocols or if survivorship is difficult to gauge. Strategic enrichment programs targeted toward developing specific skills important for survival in the wild promise to improve reintroduction success by providing individuals with opportunities to develop and improve behavioral skills, such as avoiding predation, foraging (especially for predators and primates), interacting in social groups, courtship and mating, habitat selection, and learning movement and migration routes. Enrichment also improves the physical condition of most individuals, which should also increase reintroduction success. Last but not least, such programs offer the prospect of improved animal welfare both pre- and post-release. We explore how behavioral enrichment has influenced reintroduction success and welfare in a variety of different species.

  17. Selective Increase of Auditory Cortico-Striatal Coherence during Auditory-Cued Go/NoGo Discrimination Learning

    PubMed Central

    Schulz, Andreas L.; Woldeit, Marie L.; Gonçalves, Ana I.; Saldeitis, Katja; Ohl, Frank W.

    2016-01-01

    Goal directed behavior and associated learning processes are tightly linked to neuronal activity in the ventral striatum. Mechanisms that integrate task relevant sensory information into striatal processing during decision making and learning are implicitly assumed in current reinforcement models, yet they are still weakly understood. To identify the functional activation of cortico-striatal subpopulations of connections during auditory discrimination learning, we trained Mongolian gerbils in a two-way active avoidance task in a shuttlebox to discriminate between falling and rising frequency modulated tones with identical spectral properties. We assessed functional coupling by analyzing the field-field coherence between the auditory cortex and the ventral striatum of animals performing the task. During the course of training, we observed a selective increase of functional coupling during Go-stimulus presentations. These results suggest that the auditory cortex functionally interacts with the ventral striatum during auditory learning and that the strengthening of these functional connections is selectively goal-directed. PMID:26793085

  18. Student science enrichment training program

    SciTech Connect

    Sandhu, S.S.

    1994-08-01

    This is a report on the Student Science Enrichment Training Program, with special emphasis on chemical and computer science fields. The residential summer session was held at the campus of Claflin College, Orangeburg, SC, for six weeks during 1993 summer, to run concomitantly with the college`s summer school. Fifty participants selected for this program, included high school sophomores, juniors and seniors. The students came from rural South Carolina and adjoining states which, presently, have limited science and computer science facilities. The program focused on high ability minority students, with high potential for science engineering and mathematical careers. The major objective was to increase the pool of well qualified college entering minority students who would elect to go into science, engineering and mathematical careers. The Division of Natural Sciences and Mathematics and engineering at Claflin College received major benefits from this program as it helped them to expand the Departments of Chemistry, Engineering, Mathematics and Computer Science as a result of additional enrollment. It also established an expanded pool of well qualified minority science and mathematics graduates, which were recruited by the federal agencies and private corporations, visiting Claflin College Campus. Department of Energy`s relationship with Claflin College increased the public awareness of energy related job opportunities in the public and private sectors.

  19. Disproportional plastome-wide increase of substitution rates and relaxed purifying selection in genes of carnivorous Lentibulariaceae.

    PubMed

    Wicke, Susann; Schäferhoff, Bastian; dePamphilis, Claude W; Müller, Kai F

    2014-03-01

    Carnivorous Lentibulariaceae exhibit the most sophisticated implementation of the carnivorous syndrome in plants. Their unusual lifestyle coincides with distinct genomic peculiarities such as the smallest angiosperm nuclear genomes and extremely high nucleotide substitution rates across all genomic compartments. Here, we report the complete plastid genomes from each of the three genera Pinguicula, Utricularia, and Genlisea, and investigate plastome-wide changes in their molecular evolution as the carnivorous syndrome unfolds. We observe a size reduction by up to 9% mostly due to the independent loss of genes for the plastid NAD(P)H dehydrogenase and altered proportions of plastid repeat DNA, as well as a significant plastome-wide increase of substitution rates and microstructural changes. Protein-coding genes across all gene classes show a disproportional elevation of nonsynonymous substitutions, particularly in Utricularia and Genlisea. Significant relaxation of purifying selection relative to noncarnivores occurs in the plastid-encoded fraction of the photosynthesis ATP synthase complex, the photosystem I, and in several other photosynthesis and metabolic genes. Shifts in selective regimes also affect housekeeping genes including the plastid-encoded polymerase, for which evidence for relaxed purifying selection was found once during the transition to carnivory, and a second time during the diversification of the family. Lentibulariaceae significantly exhibit enhanced rates of nucleotide substitution in most of the 130 noncoding regions. Various factors may underlie the observed patterns of relaxation of purifying selection and substitution rate increases, such as reduced net photosynthesis rates, alternative paths of nutrient uptake (including organic carbon), and impaired DNA repair mechanisms.

  20. Disproportional plastome-wide increase of substitution rates and relaxed purifying selection in genes of carnivorous Lentibulariaceae.

    PubMed

    Wicke, Susann; Schäferhoff, Bastian; dePamphilis, Claude W; Müller, Kai F

    2014-03-01

    Carnivorous Lentibulariaceae exhibit the most sophisticated implementation of the carnivorous syndrome in plants. Their unusual lifestyle coincides with distinct genomic peculiarities such as the smallest angiosperm nuclear genomes and extremely high nucleotide substitution rates across all genomic compartments. Here, we report the complete plastid genomes from each of the three genera Pinguicula, Utricularia, and Genlisea, and investigate plastome-wide changes in their molecular evolution as the carnivorous syndrome unfolds. We observe a size reduction by up to 9% mostly due to the independent loss of genes for the plastid NAD(P)H dehydrogenase and altered proportions of plastid repeat DNA, as well as a significant plastome-wide increase of substitution rates and microstructural changes. Protein-coding genes across all gene classes show a disproportional elevation of nonsynonymous substitutions, particularly in Utricularia and Genlisea. Significant relaxation of purifying selection relative to noncarnivores occurs in the plastid-encoded fraction of the photosynthesis ATP synthase complex, the photosystem I, and in several other photosynthesis and metabolic genes. Shifts in selective regimes also affect housekeeping genes including the plastid-encoded polymerase, for which evidence for relaxed purifying selection was found once during the transition to carnivory, and a second time during the diversification of the family. Lentibulariaceae significantly exhibit enhanced rates of nucleotide substitution in most of the 130 noncoding regions. Various factors may underlie the observed patterns of relaxation of purifying selection and substitution rate increases, such as reduced net photosynthesis rates, alternative paths of nutrient uptake (including organic carbon), and impaired DNA repair mechanisms. PMID:24344209

  1. Prion Protein and Stage Specific Embryo Antigen 1 as Selection Markers to Enrich the Fraction of Murine Embryonic Stem Cell-Derived Cardiomyocytes

    PubMed Central

    Ikeda, Nobuhito; Nakayama, Yuji; Nakazawa, Natsumi; Yoshida, Akio; Ninomiya, Haruaki; Shirayoshi, Yasuaki

    2016-01-01

    Background The prion protein (PrP) might be useful as a tool to collect cardiac progenitor cells derived from embryonic stem (ES) cells. It is also possible that PrP+ cells include undifferentiated cells with a capacity to develop into tumors. Methods PrP+ cells isolated from embryoid bodies (EB) formed by mouse AB1 ES cells were examined using RT–PCR analysis and clonogeneic cell assay. To assess their potential to differentiate into cardiomyocytes, Nkx2.5GFP/+ (hcgp7) cells, another ES cell line that carries the GFP reporter gene in the Nkx2.5 loci, were used. Results PrP+ cells isolated from EB of day 7 and 14 did not express pluripotency markers, but expressed cardiac cell markers, while PrP+ cells isolated from EB of day 21 expressed pluripotency markers. Cultured PrP+ cells isolated from EB of day 21 expressed pluripotency markers to form colonies, whereas those isolated from EB of day 7 and 14 did not. To exclude proliferating cells from PrP+ cells, stage specific embryo antigen 1 (SSEA1) was employed as a second marker. PrP+/SSEA1– cells did not proliferate and expressed cardiac cell markers, while PrP+/SSEA1+ did proliferate. Conclusion PrP+ cells isolated from EB included undifferentiated cells in day 21. PrP+/SSEA1– cells included cardiomyoctes, suggesting PrP and SSEA1 may be useful as markers to enrich the fraction of cardiomyocytes. PMID:27493483

  2. CLL Exosomes Modulate the Transcriptome and Behaviour of Recipient Stromal Cells and Are Selectively Enriched in miR-202-3p.

    PubMed

    Farahani, Mosavar; Rubbi, Carlos; Liu, Luning; Slupsky, Joseph R; Kalakonda, Nagesh

    2015-01-01

    Bi-directional communication with the microenvironment is essential for homing and survival of cancer cells with implications for disease biology and behaviour. In chronic lymphocytic leukemia (CLL), the role of the microenvironment on malignant cell behaviour is well described. However, how CLL cells engage and recruit nurturing cells is poorly characterised. Here we demonstrate that CLL cells secrete exosomes that are nanovesicles originating from the fusion of multivesicular bodies with the plasma membrane, to shuttle proteins, lipids, microRNAs (miR) and mRNAs to recipient cells. We characterise and confirm the size (50-100 nm) and identity of the CLL-derived exosomes by Electron microscopy (EM), Atomic force microscopy (AFM), flow cytometry and western blotting using both exosome- and CLL-specific markers. Incubation of CLL-exosomes, derived either from cell culture supernatants or from patient plasma, with human stromal cells shows that they are readily taken up into endosomes, and induce expression of genes such as c-fos and ATM as well as enhance proliferation of recipient HS-5 cells. Furthermore, we show that CLL exosomes encapsulate abundant small RNAs and are enriched in certain miRs and specifically hsa-miR-202-3p. We suggest that such specific packaging of miR-202-3p into exosomes results in enhanced expression of 'suppressor of fused' (Sufu), a Hedgehog (Hh) signalling intermediate, in the parental CLL cells. Thus, our data show that CLL cells secrete exosomes that alter the transcriptome and behaviour of recipient cells. Such communication with microenvironment is likely to have an important role in CLL disease biology. PMID:26509439

  3. Detection of Ralstonia solanacearum from asymptomatic tomato plants, irrigation water, and soil through non-selective enrichment medium with hrp gene-based bio-PCR.

    PubMed

    Singh, Dinesh; Sinha, Shweta; Yadav, D K; Chaudhary, Garima

    2014-08-01

    Bacterial wilt of tomato caused by Ralstonia solanacearum (Smith) Yabuuchi et al. (Microbiol Immunol 39:897-904, 1995) is a serious disease, which causes losses up to 60 % depending on environmental conditions, soil property, and cultivars. In present investigation, nucleotide sequences of virulence, hypersensitive response and pathogenicity (hrp) gene were used to design a pair of primer (Hrp_rs 2F: 5'-AGAGGTCGACGCGATACAGT-3' and Hrp_rs 2R: 5'-CATGAGCAAGGACGAAGTCA-3') for amplification of bacterial genome. The genomic DNA of 27 isolates of R. solanacearum race 1 biovar 3 & 4 was amplified at 323 bp. The specificity of primer was tested on 13 strains of R. solanacearum with other group of bacteria such as Xanthomonas oryzae pv. oryzae, X. campestris pv. campestris, and X. citri subsp. citri. Primer amplified DNA fragment of R. solanacearum at 323 bp. The sensitivity of the primer was 200 cfu/ml and improved further detection level by using non-specific enrichment medium casamino acids-pepton-glucose broth followed by PCR (BIO-PCR). Out of 130 samples of asymptomatic tomato plants, irrigation water, and soil collected from bacterial wilt infested field in different agro-climatic regions of India, R. solanacearum was detected from 86.9, 88.5, and 90.9 per cents samples using BIO-PCR, respectively. The primer was found specific for detecting viable and virulent strains of R. solanacearum and useful for the diagnosis of R. solanacearum in tomato seedlings and monitoring of pathogen in irrigation water and soil.

  4. Opiates selectively increase intracellular calcium in developing type-1 astrocytes: role of calcium in morphine-induced morphologic differentiation.

    PubMed

    Stiene-Martin, A; Mattson, M P; Hauser, K F

    1993-12-17

    Endogenous opioids and opiate drugs inhibit nervous system maturation, in part, by affecting the growth of astrocytes. Opiates inhibit astrocyte proliferation and cause premature differentiation. The emerging importance of Ca2+ in astrocyte function prompted us to explore whether opiates might affect astrocyte development by altering Ca2+ homeostasis. Astrocyte-enriched cultures were derived from newborn ICR mouse cerebra. Quantitative fluorescent measurements of intracellular free Ca2+ ([Ca2+]i) using Fura-2 as well as fluo-3 and computer-aided image analysis showed that 1 microM morphine significantly increased [Ca2+]i in flat, polyhedral, glial fibrillary acidic protein (GFAP) immunoreactive astrocytes at 2 and 6 min, and at 72 h. Co-administration of 3 microM naloxone blocked morphine-dependent increases in [Ca2+]i. Treatment with 1 microM concentrations of the kappa-opioid receptor agonist, U69,593, but not equimolar amounts of mu ([D-Ala2,MePhe4,Gly(ol)5]enkephalin)- or delta ([D-Pen2,D-Pen5]enkephalin)-opioid receptor agonists, significantly increased [Ca2+]i in astrocytes. To assess the role of Ca2+ in morphine-induced astrocyte differentiation, untreated and 1 microM morphine-treated astrocyte cultures were incubated for 5 days in < 0.01, 0.3, 1.0, or 3.0 mM extracellular Ca2+ ([Ca2+]o), or incubated with 1.0 mM [Ca2+]o in the presence of 1 microM of the Ca2+ ionophore, A23187. The areas of single astrocytes were measured and there was a positive correlation between astrocyte area and [Ca2+]o. Morphine had an additive effect on area and form factor measures when [Ca2+]o was 1.0 mM. High [Ca2+]o (3.0 mM) alone mimicked the action of morphine. Morphine alone had no effect on astrocyte area in the presence of 3.0 mM Ca2+.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Selectivity and Mass Transfer Limitations in Pressure-Retarded Osmosis at High Concentrations and Increased Operating Pressures.

    PubMed

    Straub, Anthony P; Osuji, Chinedum O; Cath, Tzahi Y; Elimelech, Menachem

    2015-10-20

    Pressure-retarded osmosis (PRO) is a promising source of renewable energy when hypersaline brines and other high concentration solutions are used. However, membrane performance under conditions suitable for these solutions is poorly understood. In this work, we use a new method to characterize membranes under a variety of pressures and concentrations, including hydraulic pressures up to 48.3 bar and concentrations of up to 3 M NaCl. We find membrane selectivity decreases as the draw solution concentration is increased, with the salt permeability coefficient increasing by a factor of 2 when the draw concentration is changed from 0.6 to 3 M NaCl, even when the applied hydraulic pressure is maintained constant. Additionally, we find that significant pumping energy is required to overcome frictional pressure losses in the spacer-filled feed channel and achieve suitable mass transfer on the feed side of the membrane, especially at high operating pressures. For a meter-long module operating at 41 bar, we estimate feedwater will have to be pumped in at a pressure of at least 3 bar. Both the reduced selectivity and increased pumping energy requirements we observe in PRO will significantly diminish the obtainable net energy, highlighting important new challenges for development of systems utilizing hypersaline draw solutions.

  6. Derived enriched uranium market

    SciTech Connect

    Rutkowski, E.

    1996-12-01

    The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived enriched uranium hexafluoride is unresolved; US legislation places constraints on its introduction into the US market.

  7. Type 1 diabetes prevalence increasing globally and regionally: the role of natural selection and life expectancy at birth

    PubMed Central

    You, Wen-Peng; Henneberg, Maciej

    2016-01-01

    Objective Prevalence of type 1 diabetes (T1D) disease is increasing worldwide. We aim to test correlation of T1D prevalence to the reduced natural selection measured by Biological State Index (Ibs). Research design and methods Country-specific estimates of T1D prevalence, life expectancy, obesity prevalence rate, urbanization rates, per capita sugars consumption and per capita gross domestic product (GDP) were obtained. Ibs and country-specific longevity (e50) increase for each country were self-calculated. These data were then matched to T1D prevalence by country for our ecological study among 118 countries. Countries were also grouped to study the associations in different regions. SPSS V.22 was used for correlation analysis. Results Worldwide, both Ibs and life expectancy at birth (Ibs proxy) were significantly correlated to T1D prevalence in Pearson r (r=0.713, p<0.001 and r=0.722, p<0.001, respectively) and Spearman's r (r=0.724, p<0.001 and r=0.689, p<0.001, respectively). T1D prevalence was not correlated to longevity increase measured as life expectancy at 50 years old. T1D prevalence was significantly associated with Ibs (r=0.307, p<0.001) and newborn life expectancy (r=0.349, p<0.001) independent of per capita total sugar consumption, per capita GDP, urbanization and obesity prevalence in partial correlation. Globally, both life expectancy at birth and Ibs exponentially correlated to T1D prevalence. Pearson correlations generally existed in different country categorizations by geographic region, culture background and economic status. Conclusions Reduced natural selection may have contributed to the increasing T1D prevalence worldwide. T1D epidemiology study in total population may be the practical solution to identify the causes of increasing T1D prevalence. PMID:26977306

  8. An Asymmetric Increase in Inhibitory Synapse Number Underlies the Development of a Direction Selective Circuit in the Retina.

    PubMed

    Morrie, Ryan D; Feller, Marla B

    2015-06-24

    Neural circuits rely upon a precise wiring of their component neurons to perform meaningful computations. To compute the direction of motion in the visual scene, the direction selective circuit in the mouse retina depends on an asymmetry in the inhibitory neurotransmission from starburst amacrine cells (SACs) to direction selective ganglion cells (DSGCs). Specifically, depolarization of a SAC on the null side of a DSGC causes a threefold greater unitary inhibitory conductance than depolarization of a SAC on the preferred side. This asymmetry emerges during the second postnatal week of development, but its basis remains unknown. To determine the source of this asymmetry in inhibitory conductance, we conducted paired recordings between SACs and DSGCs at the beginning and end of the second postnatal week. We replaced calcium with strontium to promote asynchronous neurotransmitter release and produce quantal events. During the second postnatal week the quantal frequency but not the quantal amplitude of synaptic events increased more than threefold for null-side SAC-DSGC pairs but remained constant for preferred-side pairs. In addition, paired-pulse depression did not differ between SACs located on the null and preferred sides of DSGCs, indicating that all inhibitory SAC synapses onto a DSGC exhibit the same probability of release. Thus, the higher quantal frequency seen in null-side pairs results from a greater number of inhibitory synapses, revealing that an asymmetry in synapse number between SACs and DSGCs underlies the development of an essential component in the retina's direction selective circuit.

  9. An Asymmetric Increase in Inhibitory Synapse Number Underlies the Development of a Direction Selective Circuit in the Retina

    PubMed Central

    Morrie, Ryan D.

    2015-01-01

    Neural circuits rely upon a precise wiring of their component neurons to perform meaningful computations. To compute the direction of motion in the visual scene, the direction selective circuit in the mouse retina depends on an asymmetry in the inhibitory neurotransmission from starburst amacrine cells (SACs) to direction selective ganglion cells (DSGCs). Specifically, depolarization of a SAC on the null side of a DSGC causes a threefold greater unitary inhibitory conductance than depolarization of a SAC on the preferred side. This asymmetry emerges during the second postnatal week of development, but its basis remains unknown. To determine the source of this asymmetry in inhibitory conductance, we conducted paired recordings between SACs and DSGCs at the beginning and end of the second postnatal week. We replaced calcium with strontium to promote asynchronous neurotransmitter release and produce quantal events. During the second postnatal week the quantal frequency but not the quantal amplitude of synaptic events increased more than threefold for null-side SAC-DSGC pairs but remained constant for preferred-side pairs. In addition, paired-pulse depression did not differ between SACs located on the null and preferred sides of DSGCs, indicating that all inhibitory SAC synapses onto a DSGC exhibit the same probability of release. Thus, the higher quantal frequency seen in null-side pairs results from a greater number of inhibitory synapses, revealing that an asymmetry in synapse number between SACs and DSGCs underlies the development of an essential component in the retina's direction selective circuit. PMID:26109653

  10. Betulinic Acid Selectively Increases Protein Degradation and Enhances Prostate Cancer-Specific Apoptosis: Possible Role for Inhibition of Deubiquitinase Activity

    PubMed Central

    Reiner, Teresita; Parrondo, Ricardo; de las Pozas, Alicia; Palenzuela, Deanna; Perez-Stable, Carlos

    2013-01-01

    Inhibition of the ubiquitin-proteasome system (UPS) of protein degradation is a valid anti-cancer strategy and has led to the approval of bortezomib for the treatment of multiple myeloma. However, the alternative approach of enhancing the degradation of oncoproteins that are frequently overexpressed in cancers is less developed. Betulinic acid (BA) is a plant-derived small molecule that can increase apoptosis specifically in cancer but not in normal cells, making it an attractive anti-cancer agent. Our results in prostate cancer suggested that BA inhibited multiple deubiquitinases (DUBs), which resulted in the accumulation of poly-ubiquitinated proteins, decreased levels of oncoproteins, and increased apoptotic cell death. In normal fibroblasts, however, BA did not inhibit DUB activity nor increased total poly-ubiquitinated proteins, which was associated with a lack of effect on cell death. In the TRAMP transgenic mouse model of prostate cancer, treatment with BA (10 mg/kg) inhibited primary tumors, increased apoptosis, decreased angiogenesis and proliferation, and lowered androgen receptor and cyclin D1 protein. BA treatment also inhibited DUB activity and increased ubiquitinated proteins in TRAMP prostate cancer but had no effect on apoptosis or ubiquitination in normal mouse tissues. Overall, our data suggests that BA-mediated inhibition of DUBs and induction of apoptotic cell death specifically in prostate cancer but not in normal cells and tissues may provide an effective non-toxic and clinically selective agent for chemotherapy. PMID:23424652

  11. Endothelial activation by hydrogen peroxide. Selective increases of intercellular adhesion molecule-1 and major histocompatibility complex class I.

    PubMed Central

    Bradley, J. R.; Johnson, D. R.; Pober, J. S.

    1993-01-01

    Products of activated leukocytes may alter vascular endothelial cell (EC) function. For example, ECs respond to leukocyte-derived cytokines, such as tumor necrosis factor (TNF) or interleukin-1, by reversibly altering levels of expression of specific gene products that promote inflammation. In contrast, hydrogen peroxide, a product of TNF-activated neutrophils, can produce irreversible EC injury and death. In this study, we have investigated the effects of subinjurious concentrations of hydrogen peroxide on EC inflammatory functions. Treatment with 50 to 100 mumol/L hydrogen peroxide selectively increases surface expression of intercellular adhesion molecule-1 and major histocompatibility complex class I, but not endothelial leukocyte adhesion molecule-1 (also known as E-selectin), vascular cell adhesion molecule-1, or gp96, a constitutively expressed EC surface protein. Increased major histocompatibility complex class I and intercellular adhesion molecule-1 surface expression is associated with specifically increased messenger RNA levels, suggesting selective endothelial gene activation. Hydrogen peroxide does not activate the transcription factor Nuclear Factor kappa B, an important mediator of TNF-induced gene expression. Co-treatment with hydrogen peroxide inhibits TNF-induced gene expression at 4 hours, an effect which can be attributed to reversible inhibition of TNF binding to EC surface receptors. Hydrogen peroxide also antagonizes the actions of interleukin-1. At 24 hours, TNF and hydrogen peroxide produce, at most, additive increases in intercellular adhesion molecule-1 and major histocompatibility complex class I. These results suggest that subinjurious concentrations of hydrogen peroxide can activate endothelium and that the effects of hydrogen peroxide on ECs differ from those of inflammatory cytokines. Images Figure 3 Figure 4 Figure 5 PMID:8098585

  12. A germ-line-selective advantage rather than an increased mutation rate can explain some unexpectedly common human disease mutations.

    PubMed

    Choi, Soo-Kyung; Yoon, Song-Ro; Calabrese, Peter; Arnheim, Norman

    2008-07-22

    Two nucleotide substitutions in the human FGFR2 gene (C755G or C758G) are responsible for virtually all sporadic cases of Apert syndrome. This condition is 100-1,000 times more common than genomic mutation frequency data predict. Here, we report on the C758G de novo Apert syndrome mutation. Using data on older donors, we show that spontaneous mutations are not uniformly distributed throughout normal testes. Instead, we find foci where C758G mutation frequencies are 3-4 orders of magnitude greater than the remaining tissue. We conclude this nucleotide site is not a mutation hot spot even after accounting for possible Luria-Delbruck "mutation jackpots." An alternative explanation for such foci involving positive selection acting on adult self-renewing Ap spermatogonia experiencing the rare mutation could not be rejected. Further, the two youngest individuals studied (19 and 23 years old) had lower mutation frequencies and smaller foci at both mutation sites compared with the older individuals. This implies that the mutation frequency of foci increases as adults age, and thus selection could explain the paternal age effect for Apert syndrome and other genetic conditions. Our results, now including the analysis of two mutations in the same set of testes, suggest that positive selection can increase the relative frequency of premeiotic germ cells carrying such mutations, although individuals who inherit them have reduced fitness. In addition, we compared the anatomical distribution of C758G mutation foci with both new and old data on the C755G mutation in the same testis and found their positions were not correlated with one another. PMID:18632557

  13. The SPIRIT Action Framework: A structured approach to selecting and testing strategies to increase the use of research in policy.

    PubMed

    Redman, Sally; Turner, Tari; Davies, Huw; Williamson, Anna; Haynes, Abby; Brennan, Sue; Milat, Andrew; O'Connor, Denise; Blyth, Fiona; Jorm, Louisa; Green, Sally

    2015-07-01

    The recent proliferation of strategies designed to increase the use of research in health policy (knowledge exchange) demands better application of contemporary conceptual understandings of how research shapes policy. Predictive models, or action frameworks, are needed to organise existing knowledge and enable a more systematic approach to the selection and testing of intervention strategies. Useful action frameworks need to meet four criteria: have a clearly articulated purpose; be informed by existing knowledge; provide an organising structure to build new knowledge; and be capable of guiding the development and testing of interventions. This paper describes the development of the SPIRIT Action Framework. A literature search and interviews with policy makers identified modifiable factors likely to influence the use of research in policy. An iterative process was used to combine these factors into a pragmatic tool which meets the four criteria. The SPIRIT Action Framework can guide conceptually-informed practical decisions in the selection and testing of interventions to increase the use of research in policy. The SPIRIT Action Framework hypothesises that a catalyst is required for the use of research, the response to which is determined by the capacity of the organisation to engage with research. Where there is sufficient capacity, a series of research engagement actions might occur that facilitate research use. These hypotheses are being tested in ongoing empirical work.

  14. Orchidectomy selectively increases follicle-stimulating hormone secretion in gonadotropin-releasing hormone antagonist-treated male rats.

    PubMed

    Tena-Sempere, M; Pinilla, L; Aguilar, E

    1995-03-01

    The pituitary component of the feedback mechanisms exerted by testicular factors on gonadotropin secretion was analyzed in adult male rats treated with a potent gonadotropin-releasing hormone (GnRH) antagonist. In order to discriminate between androgens and testicular peptides, groups of males were orchidectomized (to eliminate androgens and non-androgenic testicular factors) or injected with ethylene dimethane sulfonate (EDS), a selective toxin for Leydig cells (to eliminate selectively androgens) and treated for 15 days with vehicle or the GnRH antagonist Ac-D-pClPhe-D-pClPhe-D-Trp-Ser-Tyr-D-Arg-Leu-Arg-Pro-D-Ala-+ ++NH2CH3COOH (Org.30276, 5 mg/kg/72 hours). Serum concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured 7 and 14 days after the beginning of treatment. We found that: in males treated with GnRH antagonist, orchidectomy or EDS treatment did not induce any increase in LH secretion; and orchidectomy, but not EDS treatment, increased FSH secretion in GnRH-treated males. The present results show that negative feedback of testicular factors on LH secretion is mediated completely through changes in GnRH actions. In contrast, a part of the inhibitory action of the testis on FSH secretion is exerted directly at the pituitary level. It can be hypothesized that non-Leydig cell testicular factor(s) inputs at different levels of the hypothalamic-pituitary axis in controlling LH and FSH secretion.

  15. Selectively engaging β-arrestins at the angiotensin II type 1 receptor reduces blood pressure and increases cardiac performance.

    PubMed

    Violin, Jonathan D; DeWire, Scott M; Yamashita, Dennis; Rominger, David H; Nguyen, Lisa; Schiller, Kevin; Whalen, Erin J; Gowen, Maxine; Lark, Michael W

    2010-12-01

    Biased G protein-coupled receptor ligands engage subsets of the receptor signals normally stimulated by unbiased agonists. However, it is unclear whether ligand bias can elicit differentiated pharmacology in vivo. Here, we describe the discovery of a potent, selective β-arrestin biased ligand of the angiotensin II type 1 receptor. TRV120027 (Sar-Arg-Val-Tyr-Ile-His-Pro-D-Ala-OH) competitively antagonizes angiotensin II-stimulated G protein signaling, but stimulates β-arrestin recruitment and activates several kinase pathways, including p42/44 mitogen-activated protein kinase, Src, and endothelial nitric-oxide synthase phosphorylation via β-arrestin coupling. Consistent with β-arrestin efficacy, and unlike unbiased antagonists, TRV120027 increased cardiomyocyte contractility in vitro. In rats, TRV120027 reduced mean arterial pressure, as did the unbiased antagonists losartan and telmisartan. However, unlike the unbiased antagonists, which decreased cardiac performance, TRV120027 increased cardiac performance and preserved cardiac stroke volume. These striking differences in vivo between unbiased and β-arrestin biased ligands validate the use of biased ligands to selectively target specific receptor functions in drug discovery.

  16. Immunoliposome encapsulation increases cytotoxic activity and selectivity of curcumin and resveratrol against HER2 overexpressing human breast cancer cells.

    PubMed

    Catania, Angela; Barrajón-Catalán, Enrique; Nicolosi, Silvia; Cicirata, Federico; Micol, Vicente

    2013-08-01

    Natural compounds have been studied as a source of countless bioactive compounds with diverse activities. Among them, many dietary phytochemicals have been thoroughly studied for their cytotoxic or apoptotic effects in several cellular models in order to explain their anticancer capacity. Curcumin and resveratrol are two natural compounds with a large body of evidence showing their cytotoxic activity against a wide variety of cancer cells; however, their poor absorption, bioavailability, and low selectivity have limited their clinical use. With the aim of improving bioavailability and selectivity, the antiproliferative effects of free-, liposomed-, and immunoliposomed-curcumin and/or resveratrol formulations have been compared in two human breast cancer cell lines with different HER2 expression levels. The results demonstrate that when HER2-targeted immunoliposomes are coupled to trastuzumab there is a dramatic increase in the antiproliferative effects of curcumin and resveratrol in HER2 positive human breast cancer cells in comparison to regular liposomed or free forms, indicating an increase of its therapeutic effect. The enhancement of the cytotoxic effects was also correlated to the uptake of curcumin at intracellular level, as shown by using ImageStream technique. The striking efficacy of the immunoliposomed formulation containing both resveratrol and curcumin suggests a multitargeted mechanism of action that deserves further study. These findings show the potential of HER2-targeted nanovesicles to develop new drug delivery systems for cancer therapy based on these compounds and justify further preclinical trials.

  17. Coamplification at lower denaturation temperature polymerase chain reaction enables selective identification of K-Ras mutations in formalin-fixed, paraffin-embedded tumor tissues without tumor-cell enrichment.

    PubMed

    Yu, Shaorong; Xie, Li; Hou, Zhibo; Qian, Xiaoping; Yu, Lixia; Wei, Jia; Ding, Yitao; Liu, Baorui

    2011-09-01

    Conventional polymerase chain reaction-based Sanger sequencing is the standard assay for the detection of K-Ras mutations. However, this method is deficient in identifying small numbers of mutation-bearing cells, and tumor-cell enrichment methods such as microdissection or macrodissection are labor intensive and not always achievable. We applied the recently described coamplification at lower denaturation temperature polymerase chain reaction, which amplifies minority alleles selectively, to detect K-Ras mutations directly in 29 formalin-fixed, paraffin-embedded pancreatic specimens and compared the results with those of conventional polymerase chain reaction. To avoid a false-negative result from the coamplification at lower denaturation temperature polymerase chain reaction assay, we applied a more sensitive peptide nucleic acid polymerase chain reaction method as the gold standard. Dilution experiments indicated an approximately 5-fold improvement in sensitivity with coamplification at lower denaturation temperature polymerase chain reaction-based Sanger sequencing. Conventional polymerase chain reaction detected K-Ras mutations in 11 formalin-fixed, paraffin-embedded pancreatic specimens (37.9%), whereas coamplification at lower denaturation temperature polymerase chain reaction could identify all of those mutations as well as mutations in 10 additional samples, for a total of 21 (72.4%, P = .002) of 29. Unlike peptide nucleic acid polymerase chain reaction, coamplification at lower denaturation temperature polymerase chain reaction identified all K-Ras mutations in specimens in which tumor cells accounted for at least 20% of the total. Adoption of coamplification at lower denaturation temperature polymerase chain reaction is straightforward and requires no additional reagents or instruments. The technique is a good strategy to detect K-Ras mutations selectively in formalin-fixed, paraffin-embedded tissues without tumor-cell enrichment.

  18. Dairy fat blends high in α-linolenic acid are superior to n-3 fatty-acid-enriched palm oil blends for increasing DHA levels in the brains of young rats.

    PubMed

    Du, Qin; Martin, Jean-Charles; Agnani, Genevieve; Pages, Nicole; Leruyet, Pascale; Carayon, Pierre; Delplanque, Bernadette

    2012-12-01

    Achieving an appropriate docosahexaenoic acid (DHA) status in the neonatal brain is an important goal of neonatal nutrition. We evaluated how different dietary fat matrices improved DHA content in the brains of both male and female rats. Forty rats of each gender were born from dams fed over gestation and lactation with a low α-linolenic acid (ALA) diet (0.4% of fatty acids) and subjected for 6 weeks after weaning to a palm oil blend-based diet (10% by weight) that provided either 1.5% ALA or 1.5% ALA and 0.12% DHA with 0.4% arachidonic acid or to an anhydrous dairy fat blend that provided 1.5% or 2.3% ALA. Fatty acids in the plasma, red blood cells (RBCs) and whole brain were determined by gas chromatography. The 1.5% ALA dairy fat was superior to both the 1.5% ALA palm oil blends for increasing brain DHA (14.4% increase, P<.05), and the 2.3% ALA dairy blend exhibited a further increase that could be ascribed to both an ALA increase and n-6/n-3 ratio decrease. Females had significantly higher brain DHA due to a gender-to-diet interaction, with dairy fats attenuating the gender effect. Brain DHA was predicted with a better accuracy by some plasma and RBC fatty acids when used in combination (R(2) of 0.6) than when used individually (R(2)=0.47 for RBC n-3 docosapentaenoic acid at best). In conclusion, dairy fat blends enriched with ALA appear to be an interesting strategy for achieving optimal DHA levels in the brain of postweaning rats. Human applications are worth considering.

  19. Conceptus development during blastocyst elongation in lines of pigs selected for increased uterine capacity or ovulation rate.

    PubMed

    Miles, J R; Freking, B A; Blomberg, L A; Vallet, J L; Zuelke, K A

    2008-09-01

    Lines of pigs selected for increased uterine capacity have improved conceptus survival, whereas pigs selected for increased ovulation rate have decreased conceptus survival relative to an unselected control line. The objective of this study was to evaluate conceptus development during blastocyst elongation as a potential contributing factor to differences in conceptus survival rate among these pig lines. Conceptuses were recovered from pregnant control, uterine capacity, and ovulation rate line gilts at d 10 and 12 of gestation. At d 10 of gestation, conceptus morphologic diversity was assessed by comparing within-litter average conceptus diameter and the standard deviation of conceptus diameters. At d 12 of gestation, conceptus morphologic diversity was assessed by comparing blastocyst populations obtained from individual gilts. Real-time PCR analyses for transcripts involved in steroidogenesis, cellular differentiation, and immune responsiveness were performed on spherical, ovoid, and filamentous conceptuses recovered from these selection lines. Uterine flushings were also assayed for total protein and estradiol-17beta at d 10 and 12 of gestation. Morphological data were analyzed using ANOVA with the fixed effects of line, farrowing season, and their interactions. Conceptus mortality, uterine flushing, and real-time PCR data were analyzed using ANOVA with the fixed effects of line, day or blastocyst morphology, farrowing season, and their interactions. Conceptus mortality, measured as the ratio of conceptus recovery to ovulation rate, was not different between the lines on d 10 and 12 of gestation. There were no significant line effects for conceptus morphologic diversity at d 10 and 12 of gestation. Expression of transcripts associated with steroidogenesis (steroidogenic acute regulatory protein, cytochrome P450 side chain cleavage, and aromatase), cellular differentiation (cytokeratin-18 and vimentin), and immune responsiveness (interleukin-1beta) in spherical

  20. Increasing global agricultural production by reducing ozone damages via methane emission controls and ozone-resistant cultivar selection

    PubMed Central

    Avnery, Shiri; Mauzerall, Denise L; Fiore, Arlene M

    2013-01-01

    Meeting the projected 50% increase in global grain demand by 2030 without further environmental degradation poses a major challenge for agricultural production. Because surface ozone (O3) has a significant negative impact on crop yields, one way to increase future production is to reduce O3-induced agricultural losses. We present two strategies whereby O3 damage to crops may be reduced. We first examine the potential benefits of an O3 mitigation strategy motivated by climate change goals: gradual emission reductions of methane (CH4), an important greenhouse gas and tropospheric O3 precursor that has not yet been targeted for O3 pollution abatement. Our second strategy focuses on adapting crops to O3 exposure by selecting cultivars with demonstrated O3 resistance. We find that the CH4 reductions considered would increase global production of soybean, maize, and wheat by 23–102 Mt in 2030 – the equivalent of a ∼2–8% increase in year 2000 production worth $3.5–15 billion worldwide (USD2000), increasing the cost effectiveness of this CH4 mitigation policy. Choosing crop varieties with O3 resistance (relative to median-sensitivity cultivars) could improve global agricultural production in 2030 by over 140 Mt, the equivalent of a 12% increase in 2000 production worth ∼$22 billion. Benefits are dominated by improvements for wheat in South Asia, where O3-induced crop losses would otherwise be severe. Combining the two strategies generates benefits that are less than fully additive, given the nature of O3 effects on crops. Our results demonstrate the significant potential to sustainably improve global agricultural production by decreasing O3-induced reductions in crop yields. PMID:23504903

  1. The Behavioral Effects of Single Housing and Environmental Enrichment on Adult Zebrafish (Danio rerio).

    PubMed

    Collymore, Chereen; Tolwani, Ravi J; Rasmussen, Skye

    2015-05-01

    Environmental enrichment provides laboratory-housed species the opportunity to express natural behavior and exert control over their home environment, thereby minimizing stress. We sought to determine whether providing an artificial plant in the holding tank as enrichment influenced anxiety-like behaviors and place-preference choice in adult zebrafish. Fish were housed singly or in social groups of 5 for 3 wk in 1 of 4 experimental housing environments: single-housed enriched (n = 30), single-housed barren (n = 30), group-housed enriched (n = 30), and group-housed barren (n = 30). On week 4, individual fish were selected randomly from each of the experimental housing environments and tested by using novel-tank, light-dark, and place-preference tests. Housing fish singly in a barren environment increased anxiety-like behaviors in the novel-tank and light-dark behavioral tests. Single-housed zebrafish in barren tanks as well as zebrafish group-housed with conspecifics, both with and without plant enrichment, spent more time associating with conspecifics than with the artificial plant enrichment device during the place-preference test. Single-housed fish maintained in enriched tanks displayed no preference between a compartment with conspecifics or an artificial plant. Our results suggest the addition of an artificial plant as enrichment may benefit single-housed zebrafish when social housing is not possible.

  2. The Behavioral Effects of Single Housing and Environmental Enrichment on Adult Zebrafish (Danio rerio)

    PubMed Central

    Collymore, Chereen; Tolwani, Ravi J; Rasmussen, Skye

    2015-01-01

    Environmental enrichment provides laboratory-housed species the opportunity to express natural behavior and exert control over their home environment, thereby minimizing stress. We sought to determine whether providing an artificial plant in the holding tank as enrichment influenced anxiety-like behaviors and place-preference choice in adult zebrafish. Fish were housed singly or in social groups of 5 for 3 wk in 1 of 4 experimental housing environments: single-housed enriched (n = 30), single-housed barren (n = 30), group-housed enriched (n = 30), and group-housed barren (n = 30). On week 4, individual fish were selected randomly from each of the experimental housing environments and tested by using novel-tank, light–dark, and place-preference tests. Housing fish singly in a barren environment increased anxiety-like behaviors in the novel-tank and light–dark behavioral tests. Single-housed zebrafish in barren tanks as well as zebrafish group-housed with conspecifics, both with and without plant enrichment, spent more time associating with conspecifics than with the artificial plant enrichment device during the place-preference test. Single-housed fish maintained in enriched tanks displayed no preference between a compartment with conspecifics or an artificial plant. Our results suggest the addition of an artificial plant as enrichment may benefit single-housed zebrafish when social housing is not possible. PMID:26045453

  3. Age-related deficits in selective attention during encoding increase demands on episodic reconstruction during context retrieval: An ERP study.

    PubMed

    James, Taylor; Strunk, Jonathan; Arndt, Jason; Duarte, Audrey

    2016-06-01

    Previous event-related potential (ERP) and neuroimaging evidence suggests that directing attention toward single item-context associations compared to intra-item features at encoding improves context memory performance and reduces demands on strategic retrieval operations in young and older adults. In everyday situations, however, there are multiple event features competing for our attention. It is not currently known how selectively attending to one contextual feature while attempting to ignore another influences context memory performance and the processes that support successful retrieval in the young and old. We investigated this issue in the current ERP study. Young and older participants studied pictures of objects in the presence of two contextual features: a color and a scene, and their attention was directed to the object's relationship with one of those contexts. Participants made context memory decisions for both attended and unattended contexts and rated their confidence in those decisions. Behavioral results showed that while both groups were generally successful in applying selective attention during context encoding, older adults were less confident in their context memory decisions for attended features and showed greater dependence in context memory accuracy for attended and unattended contextual features (i.e., hyper-binding). ERP results were largely consistent between age groups but older adults showed a more pronounced late posterior negativity (LPN) implicated in episodic reconstruction processes. We conclude that age-related suppression deficits during encoding result in reduced selectivity in context memory, thereby increasing subsequent demands on episodic reconstruction processes when sought after details are not readily retrieved. PMID:27094851

  4. Age-related deficits in selective attention during encoding increase demands on episodic reconstruction during context retrieval: An ERP study.

    PubMed

    James, Taylor; Strunk, Jonathan; Arndt, Jason; Duarte, Audrey

    2016-06-01

    Previous event-related potential (ERP) and neuroimaging evidence suggests that directing attention toward single item-context associations compared to intra-item features at encoding improves context memory performance and reduces demands on strategic retrieval operations in young and older adults. In everyday situations, however, there are multiple event features competing for our attention. It is not currently known how selectively attending to one contextual feature while attempting to ignore another influences context memory performance and the processes that support successful retrieval in the young and old. We investigated this issue in the current ERP study. Young and older participants studied pictures of objects in the presence of two contextual features: a color and a scene, and their attention was directed to the object's relationship with one of those contexts. Participants made context memory decisions for both attended and unattended contexts and rated their confidence in those decisions. Behavioral results showed that while both groups were generally successful in applying selective attention during context encoding, older adults were less confident in their context memory decisions for attended features and showed greater dependence in context memory accuracy for attended and unattended contextual features (i.e., hyper-binding). ERP results were largely consistent between age groups but older adults showed a more pronounced late posterior negativity (LPN) implicated in episodic reconstruction processes. We conclude that age-related suppression deficits during encoding result in reduced selectivity in context memory, thereby increasing subsequent demands on episodic reconstruction processes when sought after details are not readily retrieved.

  5. Activation of ATP/UTP-selective receptors increases blood flow and blunts sympathetic vasoconstriction in human skeletal muscle

    PubMed Central

    Rosenmeier, Jaya B; Yegutkin, Gennady G; González-Alonso, José

    2008-01-01

    Sympathetic vasoconstriction is blunted in the vascular beds of contracting skeletal muscle in humans, presumably due to the action of vasoactive metabolites (functional sympatholysis). Recently, we demonstrated that infusion of ATP into the arterial circulation of the resting human leg increases blood flow and concomitantly blunts α-adrenergic vasoconstriction in a similar manner to that during moderate exercise. Here we tested the hypothesis that ATP, rather than its dephosphorylated metabolites, induces vasodilatation and sympatholysis in resting skeletal muscle via activation of ATP/UTP-selective receptors. To this aim, we first measured leg blood flow (LBF), mean arterial pressure (MAP), cardiac output (Q̇), leg arterial–venous (a–v) O2 difference, plasma ATP and soluble nucleotidase activities during intrafemoral artery infusion of adenosine, AMP, ADP, ATP or UTP in nine healthy males. Comparison of the doses of nucleotides and adenosine required for a similar increase in LBF from ∼0.5 l min−1 at baseline to ∼3.5 l min−1 (without altering MAP but increasing Q̇ significantly) revealed the following rank order of vasoactive potency: ATP (100) = UTP (100) >> adenosine (5.8) > ADP (2.7) > AMP (1.7). The infusions did not cause any shifts in plasma ATP level or soluble serum nucleotidase activities. Combined infusion of the vasodilatory compounds and the sympathetic vasoconstrictor drug tyramine increased plasma noradrenaline in all hyperaemic conditions, but only caused leg and systemic vasoconstriction and augmented O2 extraction during adenosine, AMP and ADP infusion (LBF from 3.2 ± 0.3 to 1.8 ± 0.2 l min−1; 3.7 ± 0.4 to 1.7 ± 0.2 l min−1 and 3.3 ± 0.4 to 2.4 ± 0.3 l min−1, respectively, P < 0.05). These findings in humans suggest that the vasodilatory and sympatholytic effects of exogenous ATP in the skeletal muscle vasculature are largely mediated via ATP itself rather than its dephosphorylated metabolites, most likely via binding

  6. Target-dependent enrichment of virions determines the reduction of high-throughput sequencing in virus discovery.

    PubMed

    Jensen, Randi Holm; Mollerup, Sarah; Mourier, Tobias; Hansen, Thomas Arn; Fridholm, Helena; Nielsen, Lars Peter; Willerslev, Eske; Hansen, Anders Johannes; Vinner, Lasse

    2015-01-01

    Viral infections cause many different diseases stemming both from well-characterized viral pathogens but also from emerging viruses, and the search for novel viruses continues to be of great importance. High-throughput sequencing is an important technology for this purpose. However, viral nucleic acids often constitute a minute proportion of the total genetic material in a sample from infected tissue. Techniques to enrich viral targets in high-throughput sequencing have been reported, but the sensitivity of such methods is not well established. This study compares different library preparation techniques targeting both DNA and RNA with and without virion enrichment. By optimizing the selection of intact virus particles, both by physical and enzymatic approaches, we assessed the effectiveness of the specific enrichment of viral sequences as compared to non-enriched sample preparations by selectively looking for and counting read sequences obtained from shotgun sequencing. Using shotgun sequencing of total DNA or RNA, viral targets were detected at concentrations corresponding to the predicted level, providing a foundation for estimating the effectiveness of virion enrichment. Virion enrichment typically produced a 1000-fold increase in the proportion of DNA virus sequences. For RNA virions the gain was less pronounced with a maximum 13-fold increase. This enrichment varied between the different sample concentrations, with no clear trend. Despite that less sequencing was required to identify target sequences, it was not evident from our data that a lower detection level was achieved by virion enrichment compared to shotgun sequencing.

  7. Environmental enrichment for dendrobatid frogs.

    PubMed

    Hurme, Kristiina; Gonzalez, Kitzi; Halvorsen, Mark; Foster, Bruce; Moore, Don; Chepko-Sade, B Diane

    2003-01-01

    The Central Park Zoo, one of the Wildlife Conservation Society's Living Institutions in New York, recently renovated an exhibit for dart-poison frogs. Staff developed a new hollow coconut insect feeder in conjunction with this project. When the exhibit change, coconut feeder, and other enrichments were tested for effectiveness, the coconut feeder enrichment produced the greatest increase in frog activity in traditional and new exhibits. This may be due to the coconut feeder's relatively complicated nature, which randomizes the release of insects into the exhibit. The goal of this project was to help develop a best-practices approach to dendrobatid husbandry for zoological facilities to use in the future.

  8. Natural resistance to experimental feline infectious peritonitis virus infection is decreased rather than increased by positive genetic selection.

    PubMed

    Pedersen, Niels C; Liu, Hongwei; Durden, Monica; Lyons, Leslie A

    2016-03-01

    A previous study demonstrated the existence of a natural resistance to feline infectious peritonitis virus (FIPV) among 36% of randomly bred laboratory cats. A genome wide association study (GWAS) on this population suggested that resistance was polygenic but failed to identify any strong specific associations. In order to enhance the power of GWAS or whole genome sequencing to identify strong genetic associations, a decision was made to positively select for resistance over three generations. The inbreeding experiment began with a genetically related parental (P) population consisting of three toms and four queens identified from among the survivors of the earlier study and belonging to a closely related subgroup (B). The subsequent effects of inbreeding were measured using 42 genome-wide STR markers. P generation cats produced 57 first filial (F1) kittens, only five of which (9.0%) demonstrated a natural resistance to FIPV infection. One of these five F1 survivors was then used to produce six F1/P-backcrosses kittens, only one of which proved resistant to FIP. Six of eight of the F1 and F1/P survivors succumbed to a secondary exposure 4-12 months later. Therefore, survival after both primary and secondary infection was decreased rather than increased by positive selection for resistance. The common genetic factor associated with this diminished resistance was a loss of heterozygosity.

  9. Increased Potassium Absorption Confers Resistance to Group IA Cations in Rubidium-Selected Suspension Cells of Brassica napus1

    PubMed Central

    Lefebvre, Daniel D.

    1989-01-01

    Cell lines of suspension cultures of Brassica napus cv. Jet Neuf were identified for their ability to tolerate 100 millimolar Rb+, a level which was double the normally lethal concentration. Ten spontaneous isolates were obtained from approximately 5 × 107 cells, one of which was reestablished as a cell suspension. This cell line, JL5, was also resistant to the other group IA cations— Li+, Na+, K+, and Cs+—and this trait was stable for at least 30 cell generations in the absence of Rb+ selection pressure. The growth characteristics were similar to those of sensitive cells under nonselective conditions. The selected JL5 cells were shown by analysis to have effected more net accumulation of K+ and Rb+ and less of Na+ than did the unselected cells. JL5 and unselected cells after 14 days of culture in basal medium contained 597.2 and 258.2 micromoles of K per gram dry weight, respectively. Michaelis-Menten kinetic analysis of K+ influx showed that JL5 possessed an elevated phase 1 Vmax, but there was no alteration in its Km. This is the first time that a plant mutation has been shown to have both increased influx and net absorption of a major essential cation. Images Figure 1 PMID:16667201

  10. Selective disruption of dopamine D2 receptors in pituitary lactotropes increases body weight and adiposity in female mice.

    PubMed

    Perez Millan, Maria Ines; Luque, Guillermina Maria; Ramirez, Maria Cecilia; Noain, Daniela; Ornstein, Ana Maria; Rubinstein, Marcelo; Becu-Villalobos, Damasia

    2014-03-01

    Prolactin, a pleiotropic hormone secreted by lactotropes, has reproductive and metabolic functions. Chronically elevated prolactin levels increase food intake, but in some hyperprolactinemic states such as in the global dopamine D2 receptor (D2R) knockout mouse, food intake is not increased. Here, we conduct a cell-specific genetic dissection study using conditional mutant mice that selectively lack D2Rs from pituitary lactotropes (lacDrd2KO) to evaluate the role of elevated prolactin levels without any confounding effect of central D2Rs on motor and reward mechanisms related to food intake. LacDrd2KO female mice exhibited chronic hyperprolactinemia, pituitary hyperplasia, and a preserved GH axis. In addition, lacDrd2KO female but not male mice showed increased food intake by 3 months of age, and from 5 months onward their body weights were heavier. Marked increments in fat depots, adipocyte size, serum triglycerides, and nonesterified fatty acid levels and a decrease in lipolytic enzymes in adipose tissue were seen. Furthermore, lacDrd2KO female mice had glucose intolerance but a preserved response to insulin. In the hypothalamus, Npy mRNA expression was increased, and Pomc and Ppo mRNA levels were unaltered (in contrast to results in global D2R knockout mice). Thus, the orexigenic effect of prolactin and its action on hypothalamic Npy expression were fully evidenced, leading to increased food intake and adiposity. Our results highlight the metabolic role of prolactin and illustrate the value of studying cell-specific mutant mice to disentangle the pathophysiological mechanisms otherwise masked in null allele mutants or in animals treated with pervasive pharmacological agents.

  11. The increase of breath ammonia induced by niacin ingestion quantified by selected ion flow tube mass spectrometry.

    PubMed

    Smith, David; Wang, Tianshu; Spanel, Patrik; Bloor, Roger

    2006-06-01

    The ingestion of relatively large doses of the vitamin niacin by healthy volunteers results in a reddening of the skin, a skin 'flush'. Thus, we have carried out a study of the breath metabolites of two healthy volunteers following (i) the ingestion of 200 mg of immediate-release niacin, (ii) as (i) but preceded by the ingestion of 325 mg of aspirin that diminishes the skin 'flush', (iii) ingestion of 500 mg of slow-release niacin. On-line breath analysis was carried out using selected ion flow tube mass spectrometry, SIFT-MS. The interesting new observation is that the breath ammonia levels of both volunteers clearly increased following (i) and (ii), and an obvious skin flush did occur following (i) but not following (ii). The slow-release niacin (iii) did not result in a flush and the breath ammonia levels increased more slowly and did not reach the higher levels produced by (i) and (ii). The results of these experiments demonstrate that breath ammonia levels are dependent on the blood/plasma levels of niacin, but are not directly related to the flushing phenomenon, and that the observed increases in blood/breath ammonia levels are consistent with current knowledge of the metabolic pathways of niacin. The parallel measurements of breath isoprene are presented, which demonstrate the quality of breath analyses that can be achieved using SIFT-MS. PMID:16603796

  12. Negative Enrichment of Target Cells by Microfluidic Affinity Chromatography

    PubMed Central

    Li, Peng; Gao, Yan; Pappas, Dimitri

    2011-01-01

    A three-dimensional microfluidic channel was developed for high purity cell separations. This system featured high capture affinity using multiple vertical inlets to an affinity surface. In cell separations, positive selection (capture of the target cell) is usually employed. Negative enrichment, the capture of non-target cells and elution of target cells, has distinct advantages over positive selection. In negative enrichment, target cells are not labeled, and are not subjected to strenuous elution conditions or dilution. As a result, negative enrichment systems are amenable to multi-step processes in microfluidic systems. In previous work, we reported cell capture enhancement effects at vertical inlets to the affinity surface. In this study, we designed a chip that has multiple vertical and horizontal channels, forming a three-dimensional separation system. Enrichment of target cells showed separation purities of 92-96%, compared with straight-channel systems (77% purity). A parallelized chip was also developed for increased sample throughput. A two-channel showed similar separation purity with twice the sample flow rate. This microfluidic system, featuring high separation purity, ease of fabrication and use, is suitable for cell separations when subsequent analysis of target cells is required. PMID:21939198

  13. Prenatal exposure to selective serotonin reuptake inhibitors (SSRI) increases aggression and modulates maternal behavior in offspring mice.

    PubMed

    Svirsky, Natali; Levy, Sigal; Avitsur, Ronit

    2016-01-01

    Selective serotonin reuptake inhibitors (SSRI) are commonly prescribed antidepressant drugs in pregnant women. SSRIs cross the placental barrier and affect serotonergic neurotransmission in the fetus. Although no gross SSRI-related teratogenic effects were reported, infants born following prenatal exposure to SSRIs are at higher risk for various developmental abnormalities. The aim of this study was to examine the effects of prenatal SSRI on social and maternal behavior in mice. To this end, pregnant female dams were exposed to saline or fluoxetine (FLX) throughout pregnancy, and the behavior of the offspring was examined. The results indicate that in utero FLX increased aggression in adult males and delayed emergence of maternal behavior in adult females. Social exploration and recognition memory were not affected by prenatal FLX exposure. These findings support the notion that alterations in the development of serotonergic pathways following prenatal exposure to SSRIs are associated with changes in social and maternal behavior throughout life.

  14. Group-selective enrichment and determination of pyrethroid insecticides in aquaculture seawater via molecularly imprinted solid phase extraction coupled with gas chromatography-electron capture detection.

    PubMed

    Shi, Xizhi; Liu, Jinghua; Sun, Aili; Li, Dexiang; Chen, Jiong

    2012-03-01

    Two types of molecularly imprinted polymers (MIPs) for the simultaneous determination of six pyrethroid insecticides have been developed using deltamethrin (D-MIPs) and cypermethrin (C-MIPs) as template molecules. A comparison of the performance of D-MIPs, C-MIPs, and the corresponding non-imprinted polymers (NIPs) were conducted. Stronger group-selective interactions between the C-MIPs and the six pyrethroid insecticides were achieved. The MISPE method based on the C-MIPs displayed higher extraction recoveries (86.4-96.0%) with RSD values ranging from 2.4 to 7.8% for the six pyrethroid insecticides in aquaculture seawater. After the C-MIP cartridge procedure, the limits of detection and quantification for fenvalerate, deltamethrin, cypermethrin, cyfluthrin, and bifenthrin were in the 16.6-37.0 and 55.3-109.1 ng L⁻¹ ranges, respectively, and 0.68 and 2.26 μg L⁻¹ for phenothrin, respectively. The proposed MISPE method coupled with gas chromatography-electron capture detection was successfully used for the determination of the six pyrethroid insecticides in aquaculture seawater.

  15. Preparation of l-phenylalanine-imprinted solid-phase extraction sorbent by Pickering emulsion polymerization and the selective enrichment of l-phenylalanine from human urine.

    PubMed

    Li, Ji; Hu, Xiaoling; Guan, Ping; Zhang, Xiaoyan; Qian, Liwei; Zhang, Nan; Du, Chunbao; Song, Renyuan

    2016-05-01

    A novel l-phenylalanine molecularly imprinted solid-phase extraction sorbent was synthesized by the combination of Pickering emulsion polymerization and ion-pair dummy template imprinting. Compared to other polymerization methods, the molecularly imprinted polymers thus prepared exhibit a high specific surface, large pore diameter, and appropriate particle size. The key parameters for solid-phase extraction were optimized, and the result indicated that the molecularly imprinted polymer thus prepared exhibits a good recovery of 98.9% for l-phenylalanine. Under the optimized conditions of the procedure, an analytical method for l-phenylalanine was well established. By comparing the performance of the molecularly imprinted polymer and a commercial reverse-phase silica gel, the obtained molecularly imprinted polymer as an solid-phase extraction sorbent is more suitable, exhibiting high precision (relative standard deviation 3.2%, n = 4) and a low limit of detection (60.0 ± 1.9 nmol·L(-1) ) for the isolation of l-phenylalanine. Based on these results, the combination of the Pickering emulsion polymerization and ion-pair dummy template imprinting is effective for preparing selective solid-phase extraction sorbents for the separation of amino acids and organic acids from complex biological samples. PMID:26991761

  16. Selective breeding for high alcohol preference increases the sensitivity of the posterior VTA to the reinforcing effects of nicotine.

    PubMed

    Hauser, Sheketha R; Bracken, Amy L; Deehan, Gerald A; Toalston, Jamie E; Ding, Zheng-Ming; Truitt, William A; Bell, Richard L; McBride, William J; Rodd, Zachary A

    2014-09-01

    The rate of codependency for alcohol and nicotine is extremely high. Numerous studies have indicated that there is a common genetic association for alcoholism and nicotine dependency. The current experiments examined whether selective breeding for high alcohol preference in rats may be associated with increased sensitivity of the posterior ventral tegmental area (pVTA) to the reinforcing properties of nicotine. In addition, nicotine can directly bind to the serotonin-3 (5-HT3 ) receptor, which has been shown to mediate the reinforcing properties of other drugs of abuse within the pVTA Wistar rats were assigned to groups that were allowed to self-infuse 0, 10, 50, 100, 200, 400 or 800 μM nicotine in two-lever (active and inactive) operant chambers. P rats were allowed to self-infuse 0, 1, 10, 50 or 100 μM nicotine. Co-infusion of 5-HT3 receptor antagonists with nicotine into the pVTA was also determined. P rats self-infused nicotine at lower concentrations than required to support self-administration in Wistar rats. In addition, P rats received more self-infusions of 50 and 100 μM nicotine than Wistar rats; including a 5HT3 receptor antagonist (LY-278,584 or zacopride) with nicotine reduced responding on the active lever. Overall, the data support an association between selective breeding for high alcohol preference and increased sensitivity of the pVTA to the reinforcing properties of nicotine. In addition, the data suggest that activation of 5HT3 receptors may be required to maintain the local reinforcing actions of nicotine within the pVTA.

  17. Selective Inducible Nitric Oxide Synthase Inhibitor Reversed Zinc Chloride-Induced Spatial Memory Impairment via Increasing Cholinergic Marker Expression.

    PubMed

    Tabrizian, Kaveh; Azami, Kian; Belaran, Maryam; Soodi, Maliheh; Abdi, Khosrou; Fanoudi, Sahar; Sanati, Mehdi; Mottaghi Dastjerdi, Negar; Soltany Rezaee-Rad, Mohammad; Sharifzadeh, Mohammad

    2016-10-01

    Zinc, an essential micronutrient and biochemical element of the human body, plays structural, catalytic, and regulatory roles in numerous physiological functions. In the current study, the effects of a pretraining oral administration of zinc chloride (10, 25, and 50 mg/kg) for 14 consecutive days and post-training bilateral intra-hippocampal infusion of 1400W as a selective inducible nitric oxide synthase (iNOS) inhibitor (10, 50, and 100 μM/side), alone and in combination, on the spatial memory retention in Morris water maze (MWM) were investigated. Animals were trained for 4 days and tested 48 h after completion of training. Also, the molecular effects of these compounds on the expression of choline acetyltransferase (ChAT), as a cholinergic marker in the CA1 region of the hippocampus and medial septal area (MSA), were evaluated. Behavioral and molecular findings of this study showed that a 2-week oral administration of zinc chloride (50 mg/kg) impaired spatial memory retention in MWM and decreased ChAT expression. Immunohistochemical analysis of post-training bilateral intra-hippocampal infusion of 1400W revealed a significant increase in ChAT immunoreactivity. Furthermore, post-training bilateral intra-hippocampal infusion of 1400W into the CA1 region of the hippocampus reversed zinc chloride-induced spatial memory impairment in MWM and significantly increased ChAT expression in comparison with zinc chloride-treated animals. Taken together, these results emphasize the role of selective iNOS inhibitors in reversing zinc chloride-induced spatial memory deficits via modulation of cholinergic marker expression.

  18. Selective Breeding for High Alcohol Preference Increases the Sensitivity of the Posterior VTA to the Reinforcing Effects of Nicotine

    PubMed Central

    Hauser, Sheketha R.; Bracken, Amy L.; Deehan, Gerald A.; Toalston, Jamie E.; Ding, Zheng-Ming; Truitt, William A.; Bell, Richard L.; McBride, William J.; Rodd, Zachary A.

    2013-01-01

    The rate of co-dependency for alcohol and nicotine is extremely high. Numerous studies have indicated that there is a common genetic association for alcoholism and nicotine dependency. The current experiments examined whether selective breeding for high alcohol preference in rats may be associated with increased sensitivity of the posterior ventral tegmental area (pVTA) to the reinforcing properties of nicotine. In addition, nicotine can directly bind to the serotonin-3 (5-HT3) receptor, which has been shown to mediate the reinforcing properties of other drugs of abuse within the pVTA Wistar rats were assigned to groups that were allowed to self-infuse 0, 10, 50, 100, 200, 400 or 800 μM nicotine in 2-lever (active and inactive) operant chambers. P rats were allowed to self-infuse 0, 1, 10, 50 or 100 μM nicotine. Co-infusion of 5-HT3 receptor antagonists with nicotine into the pVTA was also determined. P rats self-infused nicotine at lower concentrations than required to support self-administration in Wistar rats. In addition, P rats received more self-infusions of 50 and 100 μM nicotine than Wistar rats. Including a 5HT3 receptor antagonist (LY-278,584, or zacopride) with nicotine reduced responding on the active lever. Overall, the data support an association between selective breeding for high alcohol preference and increased sensitivity of the pVTA to the reinforcing properties of nicotine. In addition, the data suggest that activation of 5HT3 receptors may be required to maintain the local reinforcing actions of nicotine within the pVTA. PMID:23496648

  19. ICI D7114 a novel selective beta-adrenoceptor agonist selectively stimulates brown fat and increases whole-body oxygen consumption.

    PubMed

    Holloway, B R; Howe, R; Rao, B S; Stribling, D; Mayers, R M; Briscoe, M G; Jackson, J M

    1991-09-01

    1. ICI D7114 is a novel, beta-adrenoceptor agonist which stimulates whole body oxygen consumption in conscious rats, cats and dogs and brown adipose tissue (BAT) activity in conscious rats. Treatment of rats with ICI D7114 stimulated oxygen consumption (ED50, 0.04 mg kg-1, p.o.) and BAT mitochondrial guanosine diphosphate (GDP)-binding (ED50, 0.15 mg kg-1, p.o.) with no chronotropic effects on the heart at these doses. 2. Reference beta-adrenoceptor agonists, isoprenaline and clenbuterol, also stimulated oxygen consumption and BAT activity but were less selective because they also produced effects on heart rate at these doses. 3. Treatment of conscious rats with ICI D7114 did not attenuate the chronotropic effects on the heart of a subsequent isoprenaline challenge. 4. Administration of ICI D7114 or of its acid metabolite had no effect in a cat soleus muscle model of tremor or on blood potassium levels in the conscious dog, indicating lack of effects at beta 2-adrenoceptors. 5. The results indicate that ICI D7114 may have activity at atypical beta-adrenoceptors in brown adipose tissue leading to increased whole body oxygen consumption. PMID:1686210

  20. ICI D7114 a novel selective beta-adrenoceptor agonist selectively stimulates brown fat and increases whole-body oxygen consumption.

    PubMed Central

    Holloway, B. R.; Howe, R.; Rao, B. S.; Stribling, D.; Mayers, R. M.; Briscoe, M. G.; Jackson, J. M.

    1991-01-01

    1. ICI D7114 is a novel, beta-adrenoceptor agonist which stimulates whole body oxygen consumption in conscious rats, cats and dogs and brown adipose tissue (BAT) activity in conscious rats. Treatment of rats with ICI D7114 stimulated oxygen consumption (ED50, 0.04 mg kg-1, p.o.) and BAT mitochondrial guanosine diphosphate (GDP)-binding (ED50, 0.15 mg kg-1, p.o.) with no chronotropic effects on the heart at these doses. 2. Reference beta-adrenoceptor agonists, isoprenaline and clenbuterol, also stimulated oxygen consumption and BAT activity but were less selective because they also produced effects on heart rate at these doses. 3. Treatment of conscious rats with ICI D7114 did not attenuate the chronotropic effects on the heart of a subsequent isoprenaline challenge. 4. Administration of ICI D7114 or of its acid metabolite had no effect in a cat soleus muscle model of tremor or on blood potassium levels in the conscious dog, indicating lack of effects at beta 2-adrenoceptors. 5. The results indicate that ICI D7114 may have activity at atypical beta-adrenoceptors in brown adipose tissue leading to increased whole body oxygen consumption. PMID:1686210

  1. Management's Ecstasy and Disparity Over Job Enrichment

    ERIC Educational Resources Information Center

    King, Albert S.

    1976-01-01

    A case study analyzing job enrichment schemes and manager expectations of increased productivity is presented. It was found that it was the managers' expectations of increased productivity, not the reorganization of work, that led to higher productivity. (EC)

  2. Mixed hemimicelles solid-phase extraction based on sodium dodecyl sulfate-coated nano-magnets for selective adsorption and enrichment of illegal cationic dyes in food matrices prior to high-performance liquid chromatography-diode array detection detection.

    PubMed

    Qi, Ping; Liang, Zhi-an; Wang, Yu; Xiao, Jian; Liu, Jia; Zhou, Qing-qiong; Zheng, Chun-hao; Luo, Li-Ni; Lin, Zi-hao; Zhu, Fang; Zhang, Xue-wu

    2016-03-11

    In this study, mixed hemimicelles solid-phase extraction (MHSPE) based on sodium dodecyl sulfate (SDS) coated nano-magnets Fe3O4 was investigated as a novel method for the extraction and separation of four banned cationic dyes, Auramine O, Rhodamine B, Basic orange 21 and Basic orange 22, in condiments prior to HPLC detection. The main factors affecting the extraction of analysts, such as pH, surfactant and adsorbent concentrations and zeta potential were studied and optimized. Under optimized conditions, the proposed method was successful applied for the analysis of banned cationic dyes in food samples such as chili sauce, soybean paste and tomato sauce. Validation data showed the good recoveries in the range of 70.1-104.5%, with relative standard deviations less than 15%. The method limits of determination/quantification were in the range of 0.2-0.9 and 0.7-3μgkg(-1), respectively. The selective adsorption and enrichment of cationic dyes were achieved by the synergistic effects of hydrophobic interactions and electrostatic attraction between mixed hemimicelles and the cationic dyes, which also resulted in the removal of natural pigments interferences from sample extracts. When applied to real samples, RB was detected in several positive samples (chili powders) within the range from 0.042 to 0.177mgkg(-1). These results indicate that magnetic MHSPE is an efficient and selective sample preparation technique for the extraction of banned cationic dyes in a complex matrix. PMID:26877180

  3. Mixed hemimicelles solid-phase extraction based on sodium dodecyl sulfate-coated nano-magnets for selective adsorption and enrichment of illegal cationic dyes in food matrices prior to high-performance liquid chromatography-diode array detection detection.

    PubMed

    Qi, Ping; Liang, Zhi-an; Wang, Yu; Xiao, Jian; Liu, Jia; Zhou, Qing-qiong; Zheng, Chun-hao; Luo, Li-Ni; Lin, Zi-hao; Zhu, Fang; Zhang, Xue-wu

    2016-03-11

    In this study, mixed hemimicelles solid-phase extraction (MHSPE) based on sodium dodecyl sulfate (SDS) coated nano-magnets Fe3O4 was investigated as a novel method for the extraction and separation of four banned cationic dyes, Auramine O, Rhodamine B, Basic orange 21 and Basic orange 22, in condiments prior to HPLC detection. The main factors affecting the extraction of analysts, such as pH, surfactant and adsorbent concentrations and zeta potential were studied and optimized. Under optimized conditions, the proposed method was successful applied for the analysis of banned cationic dyes in food samples such as chili sauce, soybean paste and tomato sauce. Validation data showed the good recoveries in the range of 70.1-104.5%, with relative standard deviations less than 15%. The method limits of determination/quantification were in the range of 0.2-0.9 and 0.7-3μgkg(-1), respectively. The selective adsorption and enrichment of cationic dyes were achieved by the synergistic effects of hydrophobic interactions and electrostatic attraction between mixed hemimicelles and the cationic dyes, which also resulted in the removal of natural pigments interferences from sample extracts. When applied to real samples, RB was detected in several positive samples (chili powders) within the range from 0.042 to 0.177mgkg(-1). These results indicate that magnetic MHSPE is an efficient and selective sample preparation technique for the extraction of banned cationic dyes in a complex matrix.

  4. Oxytocin selectively increases perceptions of harm for victims but not the desire to punish offenders of criminal offenses

    PubMed Central

    Parasuraman, Raja; Moody, Lara; Twieg, Peter; de Visser, Ewart; McCabe, Kevin; O’Hara, Martin; Lee, Mary R.

    2013-01-01

    The neuropeptide oxytocin functions as a hormone and neurotransmitter and facilitates complex social cognition and approach behavior. Given that empathy is an essential ingredient for third-party decision-making in institutions of justice, we investigated whether exogenous oxytocin modulates empathy of an unaffected third-party toward offenders and victims of criminal offenses. Healthy male participants received intranasal oxytocin or placebo in a randomized, double-blind, placebo-controlled, between-subjects design. Participants were given a set of legal vignettes that described an event during which an offender engaged in criminal offenses against victims. As an unaffected third-party, participants were asked to rate those criminal offenses on the degree to which the offender deserved punishment and how much harm was inflicted on the victim. Exogenous oxytocin selectively increased third-party decision-makers’ perceptions of harm for victims but not the desire to punish offenders of criminal offenses. We argue that oxytocin promoted empathic concern for the victim, which in turn increased the tendency for prosocial approach behavior regarding the interpersonal relationship between an unaffected third-party and a fictional victim in the criminal scenarios. Future research should explore the context- and person-dependent nature of exogenous oxytocin in individuals with antisocial personality disorder and psychopathy, in whom deficits in empathy feature prominently. PMID:22368214

  5. Increased Heating Efficiency and Selective Thermal Ablation of Malignant Tissue with DNA-Encased Multiwalled Carbon Nanotubes

    PubMed Central

    2009-01-01

    Nanoparticles, including multiwalled carbon nanotubes (MWNTs), strongly absorb near-infrared (nIR) radiation and efficiently convert absorbed energy to released heat which can be used for localized hyperthermia applications. We demonstrate for the first time that DNA-encasement increases heat emission following nIR irradiation of MWNTs, and DNA-encased MWNTs can be used to safely eradicate a tumor mass in vivo. Upon irradiation of DNA-encased MWNTs, heat is generated with a linear dependence on irradiation time and laser power. DNA-encasement resulted in a 3-fold reduction in the concentration of MWNTs required to impart a 10 °C temperature increase in bulk solution temperature. A single treatment consisting of intratumoral injection of MWNTs (100 μL of a 500 μg/mL solution) followed by laser irradiation at 1064 nm, 2.5 W/cm2 completely eradicated PC3 xenograft tumors in 8/8 (100%) of nude mice. Tumors that received only MWNT injection or laser irradiation showed growth rates indistinguishable from nontreated control tumors. Nonmalignant tissues displayed no long-term damage from treatment. The results demonstrate that DNA-encased MWNTs are more efficient at converting nIR irradiation into heat compared to nonencased MWNTs and that DNA-encased MWNTs can be used safely and effectively for the selective thermal ablation of malignant tissue in vivo. PMID:19655728

  6. Selective Small Molecule Compounds Increase BMP-2 Responsiveness by Inhibiting Smurf1-mediated Smad1/5 Degradation

    PubMed Central

    Cao, Yu; Wang, Cheng; Zhang, Xueli; Xing, Guichun; Lu, Kefeng; Gu, Yongqing; He, Fuchu; Zhang, Lingqiang

    2014-01-01

    The ubiquitin ligase Smad ubiquitination regulatory factor-1 (Smurf1) negatively regulates bone morphogenetic protein (BMP) pathway by ubiquitinating certain signal components for degradation. Thus, it can be an eligible pharmacological target for increasing BMP signal responsiveness. We established a strategy to discover small molecule compounds that block the WW1 domain of Smurf1 from interacting with Smad1/5 by structure based virtual screening, molecular experimental examination and cytological efficacy evaluation. Our selected hits could reserve the protein level of Smad1/5 from degradation by interrupting Smurf1-Smad1/5 interaction and inhibiting Smurf1 mediated ubiquitination of Smad1/5. Further, these compounds increased BMP-2 signal responsiveness and the expression of certain downstream genes, enhanced the osteoblastic activity of myoblasts and osteoblasts. Our work indicates targeting Smurf1 for inhibition could be an accessible strategy to discover BMP-sensitizers that might be applied in future clinical treatments of bone disorders such as osteopenia. PMID:24828823

  7. Increased Orbitofrontal Brain Activation after Administration of a Selective Adenosine A2A Antagonist in Cocaine Dependent Subjects

    PubMed Central

    Moeller, F. Gerard; Steinberg, Joel L.; Lane, Scott D.; Kjome, Kimberly L.; Ma, Liangsuo; Ferre, Sergi; Schmitz, Joy M.; Green, Charles E.; Bandak, Stephen I.; Renshaw, Perry F.; Kramer, Larry A.; Narayana, Ponnada A.

    2012-01-01

    Background: Positron Emission Tomography imaging studies provide evidence of reduced dopamine function in cocaine dependent subjects in the striatum, which is correlated with prefrontal cortical glucose metabolism, particularly in the orbitofrontal cortex. However, whether enhancement of dopamine in the striatum in cocaine dependent subjects would be associated with changes in prefrontal cortical brain activation is unknown. One novel class of medications that enhance dopamine function via heteromer formation with dopamine receptors in the striatum is the selective adenosine A2A receptor antagonists. This study sought to determine the effects administration of the selective adenosine A2A receptor antagonist SYN115 on brain function in cocaine dependent subjects. Methodology/Principle Findings: Twelve cocaine dependent subjects underwent two fMRI scans (one after a dose of placebo and one after a dose of 100 mg of SYN115) while performing a working memory task with three levels of difficulty (3, 5, and 7 digits). fMRI results showed that for 7-digit working memory activation there was significantly greater activation from SYN115 compared to placebo in portions of left (L) lateral orbitofrontal cortex, L insula, and L superior and middle temporal pole. Conclusion/Significance: These findings are consistent with enhanced dopamine function in the striatum in cocaine dependent subjects via blockade of adenosine A2A receptors producing increased brain activation in the orbitofrontal cortex and other cortical regions. This suggests that at least some of the changes in brain activation in prefrontal cortical regions in cocaine dependent subjects may be related to altered striatal dopamine function, and that enhancement of dopamine function via adenosine A2A receptor blockade could be explored further for amelioration of neurobehavioral deficits associated with chronic cocaine use. PMID:22654774

  8. Heat-transfer resistance measurement method (HTM)-based cell detection at trace levels using a progressive enrichment approach with highly selective cell-binding surface imprints.

    PubMed

    Bers, Karolien; Eersels, Kasper; van Grinsven, Bart; Daemen, Mat; Bogie, Jeroen F J; Hendriks, Jerome J A; Bouwmans, Evelien E; Püttmann, Christiane; Stein, Christoph; Barth, Stefan; Bos, Gerard M J; Germeraad, Wilfred T V; De Ceuninck, Ward; Wagner, Patrick

    2014-04-01

    Surface-imprinted polymers allow for specific cell detection based on simultaneous recognition of the cell shape, cell size, and cell membrane functionalities by macromolecular cell imprints. In this study, the specificity of detection and the detection sensitivity for target cells within a pool of non-target cells were analyzed for a cell-specific surface-imprinted polymer combined with a heat-transfer-based read-out technique (HTM). A modified Chinese hamster ovarian cell line (CHO-ldlD) was used as a model system on which the transmembrane protein mucin-1 (MUC1) could be excessively expressed and for which the occurrence of MUC1 glycosylation could be controlled. In specific cancer cells, the overexpressed MUC1 protein typically shows an aberrant apical distribution and glycosylation. We show that surface-imprinted polymers discriminate between cell types that (1) only differ in the expression of a specific membrane protein (MUC1) or (2) only differ in the membrane protein being glycosylated or not. Moreover, surface-imprinted polymers of cells carrying different glycoforms of the same membrane protein do target both types of cells. These findings illustrate the high specificity of cell detection that can be reached by the structural imprinting of cells in polymer layers. Competitiveness between target and non-target cells was proven to negatively affect the detection sensitivity of target cells. Furthermore, we show that the detection sensitivity can be increased significantly by repetitively exposing the surface to the sample and eliminating non-specifically bound cells by flushing between consecutive cell exposures.

  9. Method for isotope enrichment by photoinduced chemiionization

    DOEpatents

    Dubrin, James W.

    1985-01-01

    Isotope enrichment, particularly .sup.235 U enrichment, is achieved by irradiating an isotopically mixed vapor feed with radiant energy at