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Sample records for abundant endogenous lipid

  1. Exogenous and endogenous lipids of human hair.

    Science.gov (United States)

    Coderch, L; Oliver, M A; Martínez, V; Manich, A M; Rubio, L; Martí, M

    2017-11-01

    The aim of this study was to characterize the external and internal lipids of Caucasian hair and their influence in different hair properties such as moisture content, hydrophobic character, and mechanical properties. Lipid extraction and their analysis by thin layer chromatography with flame ionization detector were carried out. Lipid rearrangement and water sorption and desorption evaluation of these fibers with and without lipids will also be determined using different techniques such as differential scanning calorimetry, thermogravimetric analysis and dynamic vapor sorption, mainly to evaluate permeation changes of these hair fibers possibly related to the fluidity of the lipids extracted. Caucasian fibers were found to be well hydrated, and moisture diminution was observed mainly for the external lipid extracted fibers. Unexpectedly, the lipid extraction promoted an increase in the break tenacity of the Caucasian fibers. The hydrophobic character of the fiber surfaces indicates the marked hydrophobicity of all fibers. Delipidization promotes only a slight diminution of their hydrophobic properties. Water uptake and desorption studies indicate an important water regain for Caucasian fibers. The external extracted hair fibers presented a diminution of maximum water regain, which surprisingly increases with the following internal lipid extraction. This can be due to a higher water desorption found only for external extracted fibers. The relationship between fluidity of lipids extracted and hair fiber water diffusion were established. Extraction of internal lipids of Caucasian fibers, which have a higher unsaturated lipid content than external lipids of the same hair fiber, leads to a lower water permeability of the fiber. On the capillar formulations should be considered the importance of lipid fluidity to modify the permeability of the fiber. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. The role of endogenous lipids in the emulsifying properties of cocoa

    Science.gov (United States)

    Gould, Joanne; Furse, Samuel; Wolf, Bettina

    2016-03-01

    This paper describes a study in which the emulsifying properties of cocoa material with and without its lipid fraction were explored. This study was motivated by the commercial interest in naturally-occurring particulate emulsifiers as opposed to the chemically modified emulsifying particles presently available for commercial use. The hypothesis was that endogenous lipids from cocoa were responsible for driving the formation of stable oil-in-water (o/w) emulsions. The data presented includes relative quantification of phospholipids from different commercially available cocoa material using 31P NMR spectroscopy and analyses of the emulsifying power of delipidified cocoa material. The commercially available cocoa material comprised several phospholipids, with phosphatidylcholine being the most abundant in all samples. Dispersions of delipidified cocoa material were found to drive the formation of o/w emulsions despite the absence of lipids. We therefore concluded that the emulsifying behaviour of cocoa material is not entirely reliant upon the endogenous lipids. This suggests that cocoa material may have a new and potentially widespread use in industrial food preparation and may inform manufacturing strategies for novel food grade emulsifiers.

  3. Opportunistic activation of TRP receptors by endogenous lipids: exploiting lipidomics to understand TRP receptor cellular communication.

    Science.gov (United States)

    Bradshaw, Heather B; Raboune, Siham; Hollis, Jennifer L

    2013-03-19

    Transient receptor potential channels (TRPs) form a large family of ubiquitous non-selective cation channels that function as cellular sensors and in many cases regulate intracellular calcium. Identification of the endogenous ligands that activate these TRP receptors is still under intense investigation with the majority of these channels still remaining "orphans." That these channels respond to a variety of external stimuli (e.g. plant-derived lipids, changes in temperature, and changes in pH) provides a framework for their abilities as cellular sensors, however, the mechanism of direct activation is still under much debate and research. In the cases where endogenous ligands (predominately lipids) have shown direct activation of a channel, multiple ligands have been shown to activate the same channel suggesting that these receptors are "promiscuous" in nature. Lipidomics of a growing class of endogenous lipids, N-acyl amides, the most famous of which is N-arachidonoyl ethanolamine (the endogenous cannabinoid, Anandamide) is providing a novel set of ligands that have been shown to activate some members of the TRP family and have the potential to deorphanize many more. Here it is argued that activation of TRPV receptors, a subset of the larger family of TRPs, by multiple endogenous lipids that are structurally analogous is a model system to drive our understanding that many TRP receptors are not promiscuous, but are more characteristically "opportunistic" in nature; exploiting the structural similarity and biosynthesis of a narrow range of analogous endogenous lipids. In addition, this manuscript will compare the activation properties of TRPC5 to the activity profile of an "orphan" lipid, N-palmitoyl glycine; further demonstrating that lipidomics aimed at expanding our knowledge of the family of N-acyl amides has the potential to provide novel avenues of research for TRP receptors. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Endogenous and exogenous factors controlling temporal abundance patterns of tropical mosquitoes.

    Science.gov (United States)

    Yang, Guo-Jing; Brook, Barry W; Whelan, Peter I; Cleland, Sam; Bradshaw, Corey J A

    2008-12-01

    The growing demand for efficient and effective mosquito control requires a better understanding of vector population dynamics and how these are modified by endogenous and exogenous factors. A long-term (11-year) monitoring data set describing the relative abundance of the saltmarsh mosquito (Aedes vigilax) in the greater Darwin region, northern Australia, was examined in a suite of Gompertz-logistic (GL) models with and without hypothesized environmental correlates (high tide frequency, rainfall, and relative humidity). High tide frequency and humidity were hypothesized to influence saltmarsh mosquito abundance positively, and rainfall was hypothesized to correlate negatively by reducing the availability of suitable habitats (moist substrata) required by ovipositing adult female mosquitoes. We also examined whether environmental correlates explained the variance in seasonal carrying capacity (K) because environmental stochasticity is hypothesized to modify population growth rate (r), carrying capacity, or both. Current and lagged-time effects were tested by comparing alternative population dynamics models using three different information criteria (Akaike's Information Criterion [corrected; AIC(c)], Bayesian Information Criterion [BIC], and cross-validation [C-V]). The GL model with a two-month lag without environmental effects explained 31% of the deviance in population growth rate. This increased to > 70% under various model combinations of high tide frequency, rainfall, and relative humidity, of which, high tide frequency and rainfall had the highest contributions. Temporal variation in K was explained weakly by high tide frequency, and there was some evidence that the filling of depressions to reduce standing water availability has reduced Aedes vigilax carrying capacity over the study period. This study underscores the need to consider simultaneously both types of drivers (endogenous and exogenous) when predicting mosquito abundance and population growth

  5. Effect of endogenous proteins and lipids on starch digestibility in rice flour.

    Science.gov (United States)

    Ye, Jiangping; Hu, Xiuting; Luo, Shunjing; McClements, David Julian; Liang, Lu; Liu, Chengmei

    2018-04-01

    The composition and structure of the food matrix can have a major impact on the digestion. The aim of this work was to investigate the effects of endogenous proteins and lipids on starch digestibility in rice flour, with an emphasis on establishing the underlying physicochemical mechanisms involved. Native long-grain indica rice flour and rice flour with the lipids and/or proteins removed were subjected to a simulated digestion in vitro. A significant increase in starch digestibility was observed after removal of proteins, lipids, or both. The starch digestibility of the rice flour without lipids was slightly lower than that without proteins, even though the proteins content was about 10-fold higher than the lipids content. Microstructural analysis suggested that the proteins and lipids were normally attached to the surfaces of the starch granules in the native rice flour, thus inhibiting their contact with digestive enzymes. Moreover, the proteins and lipids restricted the swelling of the starch granules, which may have decreased their digestion by reducing their surface areas. In addition, amylose-lipid complex was detected in the rice flour, which is also known to slow down starch digestion. These results have important implications for the design of foods with improved nutritional profiles. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Endogenous Lunar Volatiles: Insights into the Abundances of Volatiles in the Moon from Lunar Apatite

    Science.gov (United States)

    McCubbin, Francis

    2016-01-01

    At the time of publication of New Views of the Moon, it was thought that the Moon was bone dry with less than about 1 ppb H2O. However in 2007, initial reports at the 38th Lunar and Planetary Science Conference speculated that H-species were present in both apatites and pyroclastic volcanic lunar glasses. These early reports were later confirmed through peer-review, which motivated many subsequent studies on magmatic volatiles in and on the Moon within the last decade. Some of these studies have cast into question the post-Apollo view of lunar formation, the distribution and sources of volatiles in the Earth-Moon system, and the thermal and magmatic evolution of the Moon. The mineral apatite has been one of the pillars of this new field of study, and it will be the primary focus of this abstract. Although apatite has been used both to understand the abundances of volatiles in lunar systems as well as the isotopic compositions of those volatiles, the focus here will be on the abundances of F, Cl, and H2O. This work demonstrates the utility of apatite in advancing our understanding of lunar volatiles, hence apatite should be among the topics covered in the endogenous lunar volatile chapter in NVM II. Truncated ternary plot of apatite X-site occupancy (mol%) from highlands apatite and mare basalt apatite plotted on the relative volatile abundance diagram from. The solid black lines delineate fields of relative abundances of F, Cl, and H2O (on a weight basis) in the melt from which the apatite crystallized. The diagram was constructed using available apatite/melt partitioning data for fluorine, chlorine, and hydroxyl.

  7. Role of Endogenous and Exogenous Tocopherols in the Lipid Stability of Marine Oil Systems: A Review

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    Guadalupe Miroslava Suárez-Jiménez

    2016-11-01

    Full Text Available In marine organisms primarily intended for human consumption, the quality of the muscle and the extracted oils may be affected by lipid oxidation during storage, even at low temperatures. This has led to a search for alternatives to maintain quality. In this sense, antioxidant compounds have been used to prevent such lipid deterioration. Among the most used compounds are tocopherols, which, due to their natural origin, have become an excellent alternative to prevent or retard lipid oxidation and maintain the quality of marine products. Tocopherols as antioxidants have been studied both exogenously and endogenously. Exogenous tocopherols are often used by incorporating them into plastic packaging films or adding them directly to fish oil. It has been observed that exogenous tocopherols incorporated in low concentrations maintain the quality of both muscle and the extracted oils during food storage. However, it has been reported that tocopherols applied at higher concentrations act as a prooxidant molecule, probably because their reactions with singlet oxygen may generate free radicals and cause the oxidation of polyunsaturated fatty acids in fish oils. However, when tocopherols are included in a fish diet (endogenous tocopherols, the antioxidant effect on the muscle lipids is more effective due to their incorporation into the membrane lipids, which can help extend the shelf life of seafood by reducing the lipid deterioration that occurs due to antioxidant synergy with other phenolic compounds used supplements in fish muscle. This review focuses on the most important studies in this field and highlights the potential of using tocopherols as antioxidants in marine oils.

  8. Role of Endogenous and Exogenous Tocopherols in the Lipid Stability of Marine Oil Systems: A Review

    Science.gov (United States)

    Suárez-Jiménez, Guadalupe Miroslava; López-Saiz, Carmen María; Ramírez-Guerra, Hugo Enrique; Ezquerra-Brauer, Josafat Marina; Ruiz-Cruz, Saul; Torres-Arreola, Wilfrido

    2016-01-01

    In marine organisms primarily intended for human consumption, the quality of the muscle and the extracted oils may be affected by lipid oxidation during storage, even at low temperatures. This has led to a search for alternatives to maintain quality. In this sense, antioxidant compounds have been used to prevent such lipid deterioration. Among the most used compounds are tocopherols, which, due to their natural origin, have become an excellent alternative to prevent or retard lipid oxidation and maintain the quality of marine products. Tocopherols as antioxidants have been studied both exogenously and endogenously. Exogenous tocopherols are often used by incorporating them into plastic packaging films or adding them directly to fish oil. It has been observed that exogenous tocopherols incorporated in low concentrations maintain the quality of both muscle and the extracted oils during food storage. However, it has been reported that tocopherols applied at higher concentrations act as a prooxidant molecule, probably because their reactions with singlet oxygen may generate free radicals and cause the oxidation of polyunsaturated fatty acids in fish oils. However, when tocopherols are included in a fish diet (endogenous tocopherols), the antioxidant effect on the muscle lipids is more effective due to their incorporation into the membrane lipids, which can help extend the shelf life of seafood by reducing the lipid deterioration that occurs due to antioxidant synergy with other phenolic compounds used supplements in fish muscle. This review focuses on the most important studies in this field and highlights the potential of using tocopherols as antioxidants in marine oils. PMID:27886145

  9. Native and enzymatically modified wheat (Triticum aestivum L.) endogenous lipids in bread making: a focus on gas cell stabilization mechanisms.

    Science.gov (United States)

    Gerits, Lien R; Pareyt, Bram; Masure, Hanne G; Delcour, Jan A

    2015-04-01

    Lipopan F and Lecitase Ultra lipases were used in straight dough bread making to study how wheat lipids affect bread loaf volume (LV) and crumb structure setting. Lipase effects on LV were dose and dough piece weight dependent. The bread quality improving mechanisms exerted by endogenous lipids were studied in terms of gluten network strengthening, which indirectly stabilizes gas cells, and in terms of direct interfacial gas cell stabilization. Unlike diacetyl tartaric esters of mono- and diacylglycerols (DATEM, used as control), lipase use did not impact dough extensibility. The effect on dough extensibility was therefore related to its lipid composition at the start of mixing. Both lipases and DATEM strongly increase the levels of polar lipids in dough liquor and their availability for and potential accumulation at gas cell interfaces. Lipases form lysolipids that emulsify other lipids. We speculate that DATEM competes with (endogenous) polar lipids for interacting with gluten proteins. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Endogenous lipid (cholesterol) pneumonia in three captive Siberian tigers (Panthera tigris altaica).

    Science.gov (United States)

    Bollo, Enrico; Scaglione, Frine Eleonora; Chiappino, Laura; Sereno, Alessandra; Triberti, Orfeo; Schröder, Cathrin

    2012-05-01

    During the years 2009-2011, 7 Siberian tigers (Panthera tigris altaica), aged between 2 and 14 years, from the Safaripark of Pombia were referred for necropsy to the Department of Animal Pathology of the University of Turin (Italy). Three tigers, aged 10 (2 animals) and 14 years, had multifocal, irregularly distributed, white, soft, subpleural, 3-mm nodules scattered throughout the lungs. Histologically, there was a marked infiltration of macrophages, with foamy cytoplasm, and multinucleate giant cells interspersed with numerous clusters of cholesterol clefts. A mild lymphocytic infiltration was localized around the lesion. The findings were consistent with endogenous lipid pneumonia, which was considered an incidental finding of no clinical significance.

  11. The distribution and abundance of archaeal tetraether lipids in U.S. Great Basin hot springs

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    Julienne J. eParaiso

    2013-08-01

    Full Text Available Isoprenoidal glycerol dialkyl glycerol tetraethers (iGDGTs are core membrane lipids of many archaea that enhance the integrity of cytoplasmic membranes in extreme environments. We examined the iGDGT profiles and corresponding aqueous geochemistry in 40 hot spring sediment and microbial mat samples from the U.S. Great Basin with temperatures ranging from 31 to 95°C and pH ranging from 6.8 to 10.7. The absolute abundance of iGDGTs correlated negatively with pH and positively with temperature. High lipid concentrations, distinct lipid profiles, and a strong relationship between polar and core lipids in hot spring samples suggested in situ production of most iGDGTs rather than contamination from local soils. Two-way cluster analysis and non-metric multidimensional scaling (NMS of polar iGDGTs indicated that the relative abundance of individual lipids was most strongly related to temperature (r2 = 0.546, with moderate correlations with pH (r2 = 0.359, nitrite (r2 = 0.286, oxygen (r2 = 0.259, and nitrate (r2 = 0.215. Relative abundance profiles of individual polar iGDGTs indicated potential temperature optima for iGDGT-0 (≤70°C, iGDGT-3 (≥55°C, and iGDGT -4 (≥60°C. These relationships likely reflect both physiological adaptations and community-level population shifts in response to temperature differences, such as a shift from cooler samples with more abundant methanogens to higher-temperature samples with more abundant Crenarchaeota. Crenarchaeol was widely distributed across the temperature gradient, which is consistent with other reports of abundant crenarchaeol in Great Basin hot springs and suggests a wide distribution for thermophilic ammonia-oxidizing archaea (AOA.

  12. Linking isoprenoidal GDGT membrane lipid distributions with gene abundances of ammonia-oxidizing

    NARCIS (Netherlands)

    Buckles, L.K.; Villanueva, L.; Weijers, J.W.H.; Verschuren, D.; Sinninghe Damsté, J.S.

    2013-01-01

    Stratified lakes are important reservoirs of microbial diversity and provide habitats for niche differentiation of Archaea. In this study, we used a lipid biomarker/DNA-based approach to reveal the diversity and abundance of Archaea in the water column of Lake Challa (East Africa). Concentrations of

  13. The effects of dexketoprofen on endogenous leptin and lipid peroxidation during liver ischemia reperfusion injury.

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    Ustun, Yasemin Burcu; Koksal, Ersin; Kaya, Cengiz; Sener, Elif Bengi; Aksoy, Abdurrahman; Yarim, Gul; Kabak, Yonca; Gulbahar, Yavuz

    2014-01-01

    Hepatic ischemia reperfusion (IR) injury has complex mechanisms. We investigated the effect of dexketoprofen on endogenous leptin and malondialdehyde (MDA) levels. Wistar albino rats were divided into 4 equal groups and were subjected to 1-hour ischemia and different subsequent reperfusion intervals. Dexketoprofen was administered in a dose of 25 mg/kg 15 minutes before ischemia induction and 1-hour reperfusion to the Dexketoprofen one-hour reperfusion group, n = 6 (DIR1) group and 6-hour reperfusion to the Dexketoprofen six-hour reperfusion group, n = 6 (DIR6) group. In the control groups, 0.9% physiologic serum (SF) was administered 15 minutes before ischemia induction and 1-hour reperfusion to the one-hour reperfusion group, n = 6 (IR1) group and 6-hour reperfusion to the six-hour reperfusion group, n = 6 (IR6) group. Although serum leptin (P = 0.044) and hepatic tissue MDA levels (P = 0.004) were significantly higher in the IR6 group than in the IR1 group, there were no significant differences in dexketoprofen pretreatment between the DIR1 and DIR6 groups. There were no differences in serum MDA levels among the 4 groups, and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were significantly higher in the IR1 (P = 0.026 and P = 0.018, respectively) and IR6 (P = 0.000 and P = 0.002, respectively) groups than in the DIR1 and DIR6 groups. Dexketoprofen pretreatment can protect the liver from IR injury by decreasing inflammation and lipid peroxidation. Our study shows that dexketoprofen has no effects on endogenous leptin during IR injury.

  14. Effects of colchicine on the intestinal transport of endogenous lipid. Ultrastructural, biochemical, and radiochemical studies in fasting rats

    International Nuclear Information System (INIS)

    Pavelka, M.; Gangl, A.

    1983-01-01

    The involvement of microtubules in the transepithelial transport of exogenous lipid in intestinal absorptive cells has been suggested. Using electronmicroscopic, biochemical, and radiochemical methods, researchers have studied the effects of the antimicrotubular agent colchicine on the intestinal mucosa and on the intestinal transport of endogenous lipid of rats in the fasting state. After colchicine treatment, the concentration of triglycerides in intestinal mucosa of rats fasted for 24 h doubled, and electron microscopic studies showed a striking accumulation of lipid particles in absorptive epithelial cells of the tips of jejunal villi. These findings suggest that colchicine interferes with the intestinal transepithelial transport of endogenous lipoproteins. Additional studies, using an intraduodenal pulse injection of [ 14 C]linoleic acid, showed that colchicine does not affect the uptake of fatty acids by intestinal mucosa. However, it had divergent effects on fatty acid esterification, enhancing their incorporation into triglycerides relative to phospholipids, and caused a significant accumulation of endogenous diglycerides, triglycerides, and cholesterol esters within the absorptive intestinal epithelium. Detailed ultrastructural and morphometric studies revealed a decrease of visible microtubules, and a displacement of the smooth and rough endoplasmic reticulum and Golgi apparatus. Furthermore, it is shown that after colchicine treatment, microvilli appear at the lateral plasma membrane of intestinal absorptive cells, a change not previously reported to our knowledge. Thus, our study shows that colchicine causes significant changes in enterocyte ultrastructure and colchicine perturbs the reesterification of absorbed endogenous fatty acids and their secretion in the form of triglyceride-rich lipoproteins from the enterocyte

  15. Determination of endogenous inflammation-related lipid mediators in ischemic stroke rats using background subtracting calibration curves by liquid chromatography-tandem mass spectrometry.

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    Yang, Yang; Zhong, Qisheng; Mo, Canlong; Zhang, Hao; Zhou, Ting; Tan, Wen

    2017-11-01

    Accurate and reliable quantification of endogenous lipid mediators in complex biological samples is a daunting challenge. In this study, a robust and direct endogenous quantitative method using background subtracting calibration curves by liquid chromatography-tandem mass spectrometry was first developed for the determination of endogenous lipid mediators in ischemic stroke rats. Absolute quantification without surrogate matrix could be achieved by using background subtracting calibration curves, which were corrected and verified from standard curves constructed on original matrix. The recoveries of this method were in the range of 50.3-98.3%, the precision with the relative standard deviation was less than 13.8%, and the accuracy with the relative error was within ± 15.0%. In addition, background subtracting calibration curves were further verified by validation factors ranging from 90.3 to 110.9%. This validated method has been successfully applied to the analysis of seven endogenous inflammation-related lipid mediators in the brain tissues of ischemic stroke rats. The results indicated that prostaglandins as inflammatory factors and some lipid mediators with neuroprotective effects increased apparently (p endogenous compounds in the complex biological samples. Graphical abstract The analysis procedure of determining endogenous inflammation-related lipid mediators using BSCC by LC-MS/MS.

  16. Relationship between variations in the level of endogenous thiols and antioxidant activity of lipids and radiosensitivity of animals of different species

    International Nuclear Information System (INIS)

    Burlakova, E.B.; Graevskaya, B.M.; Ivanenko, G.F.; Shishkina, L.N.; AN SSSR, Moscow. Inst. Ehvolyutsionnoj Morfologii i Ehkologii Zhivotnykh)

    1978-01-01

    Initial levels of total and nonprotein sulfhydryl groups and antioxidant activity (AOA) of lipids of the spleen and liver are measured in animals of different species. Radiosensitivity of animals is assessed by the value of LDsub(50/30). No reliable correlation has been revealed between initial levels of endogenous thiols and AOA of lipids. There is a positive correlation between AOA of the spleen lipids and LDsub(50/30) as well as between the level of endogenous thiols and radioresistance of the animal species under study. It is likely that the level of endogenous thiols and AOA of lipids reflect various aspects of cellular metabolism which is responsible for radioresistance of the organism

  17. Responses of membrane lipid peroxidation and endogenous hormones of soybean seedlings to UV-B radiation and rare earth

    International Nuclear Information System (INIS)

    Yan Shengrong; Yang Chunhe; Zhang Yuequn

    2009-01-01

    [Objective] The aim was to provide strategies for development of rare earth and control of environmental pollution. [Method] Responses of membrane lipid peroxidation and endogenous hormones of soybean seedlings to UV-B radiation and rare earth were studied through hydroponics in laboratory. [Result] The results showed that under irradiation of UV-B(T1-0.15 W/m2 and T2-0.45 W/m2), chlorophyll and indole-3-acetic acid(IAA) contents firstly decreased during the stress phase (1-5d) and then increased during the restoration phase (6-9d) while contents of malonadialdehyde(MDA) and abscisic acid(ABA) gradually increased during the imposition of UV-B radiation (1-5d) and subsequently decreased during recovery from UV-B stress (6-9d) . With adding of La (Ⅲ) with the concentration of 20mg•L-1, the decline/rise trend of chlorophyll, IAA, MDA and ABA contents was slowed down during the stress period while the rise/decline speed was accelerated during the recovery period. [Conclusion] It suggests that the regulation of La (Ⅲ) on membrane lipid peroxidation and endogenous hormones could increase chlorophyll and IAA contents, improve the metabolism of reactive oxygen species (ROS), inhibit membrane lipid peroxidation, decrease the accumulation amount of ABA and alleviate injury of UV-B radiation to soybean seedlings. Further, the protective potential of La (Ⅲ) was better under low UV-B radiation than under high one

  18. Photoacoustic imaging of human lymph nodes with endogenous lipid and hemoglobin contrast

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    Guggenheim, James A.; Allen, Thomas J.; Plumb, Andrew; Zhang, Edward Z.; Rodriguez-Justo, Manuel; Punwani, Shonit; Beard, Paul C.

    2015-05-01

    Lymph nodes play a central role in metastatic cancer spread and are a key clinical assessment target. Abnormal node vascularization, morphology, and size may be indicative of disease but can be difficult to visualize with sufficient accuracy using existing clinical imaging modalities. To explore the potential utility of photoacoustic imaging for the assessment of lymph nodes, images of ex vivo samples were obtained at multiple wavelengths using a high-resolution three-dimensional photoacoustic scanner. These images showed that hemoglobin based contrast reveals nodal vasculature and lipid-based contrast reveals the exterior node size, shape, and boundary integrity. These two sources of complementary contrast may allow indirect observation of cancer, suggesting a future role for photoacoustic imaging as a tool for the clinical assessment of lymph nodes.

  19. Environmental toxin acrolein alters levels of endogenous lipids, including TRP agonists: A potential mechanism for headache driven by TRPA1 activation

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    Emma Leishman

    2017-01-01

    Full Text Available Exposure to airborne toxins can trigger headaches, but the mechanisms are not well understood. Some environmental toxins, such as acrolein, activate transient receptor potential ankyrin 1 (TRPA1, a receptor involved in pain sensation that is highly expressed in the trigeminovascular system. It has been shown in rat models that repeated exposure to acrolein induces trigeminovascular sensitization to both TRPA1 and TRP vanilloid 1 (TRPV1 agonists, a phenomenon linked to headache. In this study, we test the hypothesis that the sensitization of trigeminovascular responses in rats after acrolein exposure via inhalation is associated with changes in levels of endogenous lipids, including TRPV1 agonists, in the trigeminal ganglia, trigeminal nucleus, and cerebellum. Lipidomics analysis of 80 lipids was performed on each tissue after acute acrolein, chronic acrolein, or room air control. Both acute and chronic acrolein exposure drove widespread alterations in lipid levels. After chronic acrolein exposure, levels of all 6 N-acyl ethanolamines in the screening library, including the endogenous cannabinoid and TRPV1 agonist, N-arachidonoyl ethanolamine, were elevated in trigeminal tissue and in the cerebellum. This increase in TRPV1 ligands by acrolein exposure may indicate further downstream signaling, in that we also show here that a combination of these TRPV1 endogenous agonists increases the potency of the individual ligands in TRPV1-HEK cells. In addition to these TRPV1 agonists, 3 TRPV3 antagonists, 4 TRPV4 agonists, and 25 orphan lipids were up and down regulated after acrolein exposure. These data support the hypothesis that lipid signaling may represent a mechanism by which repeated exposure to the TRPA1 agonist and environmental toxin, acrolein, drives trigeminovascular sensitization. Keywords: Lipidomics, Endogenous cannabinoid, TRPA1, TRPV1, Lipoamine, Acrolein, Migraine

  20. Abundant genetic overlap between blood lipids and immune-mediated diseases indicates shared molecular genetic mechanisms.

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    Ole A Andreassen

    Full Text Available Epidemiological studies suggest a relationship between blood lipids and immune-mediated diseases, but the nature of these associations is not well understood. We used genome-wide association studies (GWAS to investigate shared single nucleotide polymorphisms (SNPs between blood lipids and immune-mediated diseases. We analyzed data from GWAS (n~200,000 individuals, applying new False Discovery Rate (FDR methods, to investigate genetic overlap between blood lipid levels [triglycerides (TG, low density lipoproteins (LDL, high density lipoproteins (HDL] and a selection of archetypal immune-mediated diseases (Crohn's disease, ulcerative colitis, rheumatoid arthritis, type 1 diabetes, celiac disease, psoriasis and sarcoidosis. We found significant polygenic pleiotropy between the blood lipids and all the investigated immune-mediated diseases. We discovered several shared risk loci between the immune-mediated diseases and TG (n = 88, LDL (n = 87 and HDL (n = 52. Three-way analyses differentiated the pattern of pleiotropy among the immune-mediated diseases. The new pleiotropic loci increased the number of functional gene network nodes representing blood lipid loci by 40%. Pathway analyses implicated several novel shared mechanisms for immune pathogenesis and lipid biology, including glycosphingolipid synthesis (e.g. FUT2 and intestinal host-microbe interactions (e.g. ATG16L1. We demonstrate a shared genetic basis for blood lipids and immune-mediated diseases independent of environmental factors. Our findings provide novel mechanistic insights into dyslipidemia and immune-mediated diseases and may have implications for therapeutic trials involving lipid-lowering and anti-inflammatory agents.

  1. Dietary counselling effectively improves lipid levels in patients with endogenous hypertriglyceridemia: emphasis on weight reduction and alcohol limitation

    NARCIS (Netherlands)

    de Man, F. H.; van der Laarse, A.; Hopman, E. G.; Gevers Leuven, J. A.; Onkenhout, W.; Dallinga-Thie, G. M.; Smelt, A. H.

    1999-01-01

    To evaluate the short-term effect of dietary counselling in patients with endogenous hypertriglyceridemia and evaluate the effects of advised nutrient changes. A prospective dietary intervention study in patients with endogenous hypertriglyceridemia from January I st 1988 to December 31 st 1996

  2. How and When Do Insects Rely on Endogenous Protein and Lipid Resources during Lethal Bouts of Starvation? A New Application for 13C-Breath testing.

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    McCue, Marshall D; Guzman, R Marena; Passement, Celeste A; Davidowitz, Goggy

    2015-01-01

    Most of our understanding about the physiology of fasting and starvation comes from studies of vertebrates; however, for ethical reasons, studies that monitor vertebrates through the lethal endpoint are scant. Insects are convenient models to characterize the comparative strategies used to cope with starvation because they have diverse life histories and have evolved under the omnipresent challenge of food limitation. Moreover, we can study the physiology of starvation through its natural endpoint. In this study we raised populations of five species of insects (adult grasshoppers, crickets, cockroaches, and larval beetles and moths) on diets labeled with either 13C-palmitic acid or 13C-leucine to isotopically enrich the lipids or the proteins in their bodies, respectively. The insects were allowed to become postabsorptive and then starved. We periodically measured the δ13C of the exhaled breath to characterize how each species adjusted their reliance on endogenous lipids and proteins as energy sources. We found that starving insects employ a wide range of strategies for regulating lipid and protein oxidation. All of the insects except for the beetle larvae were capable of sharply reducing reliance on protein oxidation; however, this protein sparing strategy was usually unsustainable during the entire starvation period. All insects increased their reliance on lipid oxidation, but while some species (grasshoppers, cockroaches, and beetle larvae) were still relying extensively on lipids at the time of death, other species (crickets and moth larvae) allowed rates of lipid oxidation to return to prestarvation levels. Although lipids and proteins are critical metabolic fuels for both vertebrates and insects, insects apparently exhibit a much wider range of strategies for rationing these limited resources during starvation.

  3. How and When Do Insects Rely on Endogenous Protein and Lipid Resources during Lethal Bouts of Starvation? A New Application for 13C-Breath testing.

    Directory of Open Access Journals (Sweden)

    Marshall D McCue

    Full Text Available Most of our understanding about the physiology of fasting and starvation comes from studies of vertebrates; however, for ethical reasons, studies that monitor vertebrates through the lethal endpoint are scant. Insects are convenient models to characterize the comparative strategies used to cope with starvation because they have diverse life histories and have evolved under the omnipresent challenge of food limitation. Moreover, we can study the physiology of starvation through its natural endpoint. In this study we raised populations of five species of insects (adult grasshoppers, crickets, cockroaches, and larval beetles and moths on diets labeled with either 13C-palmitic acid or 13C-leucine to isotopically enrich the lipids or the proteins in their bodies, respectively. The insects were allowed to become postabsorptive and then starved. We periodically measured the δ13C of the exhaled breath to characterize how each species adjusted their reliance on endogenous lipids and proteins as energy sources. We found that starving insects employ a wide range of strategies for regulating lipid and protein oxidation. All of the insects except for the beetle larvae were capable of sharply reducing reliance on protein oxidation; however, this protein sparing strategy was usually unsustainable during the entire starvation period. All insects increased their reliance on lipid oxidation, but while some species (grasshoppers, cockroaches, and beetle larvae were still relying extensively on lipids at the time of death, other species (crickets and moth larvae allowed rates of lipid oxidation to return to prestarvation levels. Although lipids and proteins are critical metabolic fuels for both vertebrates and insects, insects apparently exhibit a much wider range of strategies for rationing these limited resources during starvation.

  4. Microbial Diversity and Lipid Abundance in Microbial Mats from a Sulfidic, Saline, Warm Spring in Utah, USA

    Science.gov (United States)

    Gong, J.; Edwardson, C.; Mackey, T. J.; Dzaugis, M.; Ibarra, Y.; Course 2012, G.; Frantz, C. M.; Osburn, M. R.; Hirst, M.; Williamson, C.; Hanselmann, K.; Caporaso, J.; Sessions, A. L.; Spear, J. R.

    2012-12-01

    The microbial diversity of Stinking Springs, a sulfidic, saline, warm spring northeast of the Great Salt Lake was investigated. The measured pH, temperature, salinity, and sulfide concentration along the flow path ranged from 6.64-7.77, 40-28° C, 2.9-2.2%, and 250 μM to negligible, respectively. Five sites were selected along the flow path and within each site microbial mats were dissected into depth profiles based on the color and texture of the mat layers. Genomic DNA was extracted from each layer, and the 16S rRNA gene was amplified and sequenced on the Roche 454 Titanium platform. Fatty acids were also extracted from the mat layers and analyzed by liquid chromatography and mass spectrometry. The mats at Stinking Springs were classified into roughly two morphologies with respect to their spatial distribution: loose, sometimes floating mats proximal to the spring source; and thicker, well-laminated mats distal to the spring source. Loosely-laminated mats were found in turbulent stream flow environments, whereas well-laminated mats were common in less turbulent sheet flows. Phototrophs, sulfur oxidizers, sulfate reducers, methanogens, other bacteria and archaea were identified by 16S rRNA gene sequences. Diatoms, identified by microscopy and lipid analysis were found to increase in abundance with distance from the source. Methanogens were generally more abundant in deeper mat laminae. Photoheterotrophs were found in all mat layers. Microbial diversity increased significantly with depth at most sites. In addition, two distinct microbial streamers were identified and characterized at the two fast flowing sites. These two streamer varieties were dominated by either cyanobacteria or flavobacteria. Overall, our genomic and lipid analysis suggest that the physical and chemical environment is more predictive of the community composition than mat morphology. Site Map

  5. CD1d-mediated presentation of endogenous lipid antigens by adipocytes requires microsomal triglyceride transfer protein (MTP)

    DEFF Research Database (Denmark)

    Rakhshandehroo, Maryam; Gijzel, Sanne M W; Siersbæk, Rasmus

    2014-01-01

    -dependent fashion, but little is known about the lipid antigen presentation machinery in adipocytes. Here we show that CD1d, as well as the lipid antigen loading machinery genes pro-saposin (Psap), Niemann Pick type C2 (Npc2), α-galactosidase (Gla), are upregulated in early adipogenesis, and are transcriptionally...... presenting cells (APCs), which may present an important aspect of adipocyte-immune cell communication in the regulation of whole body energy metabolism and immune homeostasis....

  6. A Review About Lycopene-Induced Nuclear Hormone Receptor Signalling in Inflammation and Lipid Metabolism via still Unknown Endogenous Apo-10´-Lycopenoids.

    Science.gov (United States)

    Caris-Veyrat, Catherine; Garcia, Ada L; Reynaud, Eric; Lucas, Renata; Aydemir, Gamze; Rühl, Ralph

    2017-10-20

    Lycopene is the red pigment in tomatoes and tomato products and is an important dietary carotenoid found in the human organism. Lycopene-isomers, oxidative lycopene metabolites and apo-lycopenoids are found in the food matrix. Lycopene intake derived from tomato consumption is associated with alteration of lipid metabolism and a lower incidence of cardiovascular diseases (CVD). Lycopene is mainly described as a potent antioxidant but novel studies are shifting towards its metabolites and their capacity to mediate nuclear receptor signalling. Di-/tetra-hydro-derivatives of apo-10´-lycopenoic acid and apo-15´-lycopenoic acids are potential novel endogenous mammalian lycopene metabolites which may act as ligands for nuclear hormone mediated activation and signalling. In this review, we postulate that complex lycopene metabolism results in various lycopene metabolites which have the ability to mediate transactivation of various nuclear hormone receptors like RARs, RXRs and PPARs. A new mechanistic explanation of how tomato consumption could positively modulate inflammation and lipid metabolism is discussed.

  7. Evidence Suggesting That Francisella tularensis O-Antigen Capsule Contains a Lipid A-Like Molecule That Is Structurally Distinct from the More Abundant Free Lipid A.

    Directory of Open Access Journals (Sweden)

    Jason H Barker

    Full Text Available Francisella tularensis, the Gram-negative bacterium that causes tularemia, produces a high molecular weight capsule that is immunologically distinct from Francisella lipopolysaccharide but contains the same O-antigen tetrasaccharide. To pursue the possibility that the capsule of Francisella live vaccine strain (LVS has a structurally unique lipid anchor, we have metabolically labeled Francisella with [14C]acetate to facilitate highly sensitive compositional analysis of capsule-associated lipids. Capsule was purified by two independent methods and yielded similar results. Autoradiographic and immunologic analysis confirmed that this purified material was largely devoid of low molecular weight LPS and of the copious amounts of free lipid A that the Francisellae accumulate. Chemical hydrolysis yielded [14C]-labeled free fatty acids characteristic of Francisella lipid A but with a different molar ratio of 3-OH C18:0 to 3-OH C16:0 and different composition of non-hydroxylated fatty acids (mainly C14:0 rather than C16:0 than that of free Francisella lipid A. Mild acid hydrolysis to induce selective cleavage of KDO-lipid A linkage yielded a [14C]-labeled product that partitioned during Bligh/Dyer extraction and migrated during thin-layer chromatography like lipid A. These findings suggest that the O-antigen capsule of Francisella contains a covalently linked and structurally distinct lipid A species. The presence of a discrete lipid A-like molecule associated with capsule raises the possibility that Francisella selectively exploits lipid A structural heterogeneity to regulate synthesis, transport, and stable bacterial surface association of the O-antigen capsular layer.

  8. Abundant Trimethylornithine Lipids and Specific Gene Sequences Are Indicative of Planctomycete Importance at the Oxic/Anoxic Interface in Sphagnum-Dominated Northern Wetlands.

    Science.gov (United States)

    Moore, Eli K; Villanueva, Laura; Hopmans, Ellen C; Rijpstra, W Irene C; Mets, Anchelique; Dedysh, Svetlana N; Sinninghe Damsté, Jaap S

    2015-09-01

    Northern wetlands make up a substantial terrestrial carbon sink and are often dominated by decay-resistant Sphagnum mosses. Recent studies have shown that planctomycetes appear to be involved in degradation of Sphagnum-derived debris. Novel trimethylornithine (TMO) lipids have recently been characterized as abundant lipids in various Sphagnum wetland planctomycete isolates, but their occurrence in the environment has not yet been confirmed. We applied a combined intact polar lipid (IPL) and molecular analysis of peat cores collected from two northern wetlands (Saxnäs Mosse [Sweden] and Obukhovskoye [Russia]) in order to investigate the preferred niche and abundance of TMO-producing planctomycetes. TMOs were present throughout the profiles of Sphagnum bogs, but their concentration peaked at the oxic/anoxic interface, which coincided with a maximum abundance of planctomycete-specific 16S rRNA gene sequences. The sequences detected at the oxic/anoxic interface were affiliated with the Isosphaera group, while sequences present in the anoxic peat layers were related to an uncultured planctomycete group. Pyrosequencing-based analysis identified Planctomycetes as the major bacterial group at the oxic/anoxic interface at the Obukhovskoye peat (54% of total 16S rRNA gene sequence reads), followed by Acidobacteria (19% reads), while in the Saxnäs Mosse peat, Acidobacteria were dominant (46%), and Planctomycetes contributed to 6% of the total reads. The detection of abundant TMO lipids in planctomycetes isolated from peat bogs and the lack of TMO production by cultures of acidobacteria suggest that planctomycetes are the producers of TMOs in peat bogs. The higher accumulation of TMOs at the oxic/anoxic interface and the change in the planctomycete community with depth suggest that these IPLs could be synthesized as a response to changing redox conditions at the oxic/anoxic interface. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Endogenous antipyretics.

    Science.gov (United States)

    Roth, Joachim

    2006-09-01

    The febrile increase of body temperature is regarded as a component of the complex host response to infection or inflammation that accompanies the activation of the immune system. Late phases of fever appear mediated by pro-inflammatory cytokines called endogenous pyrogens. The rise of body temperature is beneficial because it accelerates several components of the activated immune system. To prevent an excessive and dangerous rise of body temperature the febrile response is controlled, limited in strength and duration, and sometimes even prevented by the actions of endogenous antipyretic substances liberated systemically or within the brain during fever. In most cases the antipyretic effects are achieved by an inhibitory influence on the formation or action of endogenous pyrogens, or by effects on neuronal thermoregulatory circuits that are activated during fever. Endogenous antipyretic substances include steroid hormones, neuropeptides, cytokines and other molecules. It is the purpose of this review to consider the current state in the research on endogenous antipyretic systems.

  10. The Endogenous Exposome

    Science.gov (United States)

    Nakamura, Jun; Mutlu, Esra; Sharma, Vyom; Collins, Leonard; Bodnar, Wanda; Yu, Rui; Lai, Yongquan; Moeller, Benjamin; Lu, Kun; Swenberg, James

    2014-01-01

    The concept of the Exposome, is a compilation of diseases and one’s lifetime exposure to chemicals, whether the exposure comes from environmental, dietary, or occupational exposures; or endogenous chemicals that are formed from normal metabolism, inflammation, oxidative stress, lipid peroxidation, infections, and other natural metabolic processes such as alteration of the gut microbiome. In this review, we have focused on the Endogenous Exposome, the DNA damage that arises from the production of endogenous electrophilic molecules in our cells. It provides quantitative data on endogenous DNA damage and its relationship to mutagenesis, with emphasis on when exogenous chemical exposures that produce identical DNA adducts to those arising from normal metabolism cause significant increases in total identical DNA adducts. We have utilized stable isotope labeled chemical exposures of animals and cells, so that accurate relationships between endogenous and exogenous exposures can be determined. Advances in mass spectrometry have vastly increased both the sensitivity and accuracy of such studies. Furthermore, we have clear evidence of which sources of exposure drive low dose biology that results in mutations and disease. These data provide much needed information to impact quantitative risk assessments, in the hope of moving towards the use of science, rather than default assumptions. PMID:24767943

  11. Endogenous Lunar Volatiles

    Science.gov (United States)

    McCubbin, F. M.; Liu, Y.; Barnes, J. J.; Boyce, J. W.; Day, J. M. D.; Elardo, S. M.; Hui, H.; Magna, T.; Ni, P.; Tartese, R.; hide

    2017-01-01

    The chapter will begin with an introduction that defines magmatic volatiles (e.g., H, F, Cl, S) versus geochemical volatiles (e.g., K, Rb, Zn). We will discuss our approach of understanding both types of volatiles in lunar samples and lay the ground work for how we will determine the overall volatile budget of the Moon. We will then discuss the importance of endogenous volatiles in shaping the "Newer Views of the Moon", specifically how endogenous volatiles feed forward into processes such as the origin of the Moon, magmatic differentiation, volcanism, and secondary processes during surface and crustal interactions. After the introduction, we will include a re-view/synthesis on the current state of 1) apatite compositions (volatile abundances and isotopic compositions); 2) nominally anhydrous mineral phases (moderately to highly volatile); 3) volatile (moderately to highly volatile) abundances in and isotopic compositions of lunar pyroclastic glass beads; 4) volatile (moderately to highly volatile) abundances in and isotopic compositions of lunar basalts; 5) volatile (moderately to highly volatile) abundances in and isotopic compositions of melt inclusions; and finally 6) experimental constraints on mineral-melt partitioning of moderately to highly volatile elements under lunar conditions. We anticipate that each section will summarize results since 2007 and focus on new results published since the 2015 Am Min review paper on lunar volatiles [9]. The next section will discuss how to use sample abundances of volatiles to understand the source region and potential caveats in estimating source abundances of volatiles. The following section will include our best estimates of volatile abundances and isotopic compositions (where permitted by available data) for each volatile element of interest in a number of important lunar reservoirs, including the crust, mantle, KREEP, and bulk Moon. The final section of the chapter will focus upon future work, outstanding questions

  12. Endogene CGRP

    OpenAIRE

    Höfer, Martina

    2010-01-01

    Hintergrund und Ziele Die vorliegende tierexperimentelle Arbeit beschäftigt sich mit der Frage, welche Rolle endogenes Calcitonin-gene related peptide (CGRP) in der Niere spielt. Hierbei untersuchten wir die renale CGRP Freisetzung aus renalen Afferenzen in vitro anhand von gesunden Tieren und einem pathologischen Modell der Glomerulonephritis. Man weiß bereits, dass sowohl sympathische als auch primär sensorische Neuronen die Entzündung und die Immunantwort in der Peripherie regulieren (68)....

  13. Distributions and Transformations of Natural Abundance 14C and 13C in Dissolved and Particulate Lipids in a Major Temperate Estuary

    Science.gov (United States)

    Bauer, J. E.; Canuel, E. A.; McIntosh, H.; Barrett, A.; Ferer, E.; Hossler, K.

    2013-12-01

    Limited previous studies have shown major differences in the natural 14C and 13C isotopic signatures and radiocarbon ages of different biochemical classes (e.g., proteins, carbohydrates, lipid, etc.) in river, estuarine and marine dissolved and particulate organic matter (DOM and POM, respectively). Of particular note are the much greater radiocarbon ages of lipophilic materials than other compound classes. Possible explanations for these findings include greater-than-expected inputs of fossil and highly aged lipid-containing organic matter to rivers and estuaries, extended sorptive-protection of lipophilic materials from degradation and/or lower overall reactivities of lipids vs. other major biochemical classes. We measured the Delta 14C and del 13C signatures and 14C ages of lipid classes in DOM and POM in a major temperate estuary, Delaware Bay (USA) over two years. Changes in DOM were also followed during large volume dark and light incubations to assess the microbial and photochemical reactivity and processing of DOM and lipids. Neutral lipids in DOM were among the most highly aged (> 30,000 yrs BP) of any materials measured in natural waters to date, and were significantly older than co-occurring polar lipids (~4,000-5,000 yrs BP). In general, DOM lipid ages were significantly greater than POM lipid ages across the river-estuary transect, arguing against sorptive protection as the major factor explaining greater ages of lipid than those of other compound classes. Both dark and light incubations of DOM resulted in losses of very highly aged material (30-50,000 y BP), with the remnant exported lipids being correspondingly younger. The microbial and photochemical alterations were most pronounced for lipids from freshwater reaches of the system (i.e., the Delaware River). These findings suggest that a) dissolved vs. particulate lipids have fundamentally different sources and/or physico-chemical partitioning, b) different lipid classes (e.g., neutral vs. polar

  14. Linking isoprenoidal GDGT membrane lipid distributions with gene abundances of ammonia-oxidizing Thaumarchaeota and uncultured crenarchaeotal groups in the water column of a tropical lake (Lake Challa, East Africa).

    Science.gov (United States)

    Buckles, Laura K; Villanueva, Laura; Weijers, Johan W H; Verschuren, Dirk; Damsté, Jaap S Sinninghe

    2013-09-01

    Stratified lakes are important reservoirs of microbial diversity and provide habitats for niche differentiation of Archaea. In this study, we used a lipid biomarker/DNA-based approach to reveal the diversity and abundance of Archaea in the water column of Lake Challa (East Africa). Concentrations of intact polar lipid (IPL) crenarchaeol, a specific biomarker of Thaumarchaeota, were enhanced (1 ng l(-1) ) at the oxycline/nitrocline. The predominance of the more labile IPL hexose-phosphohexose crenarchaeol indicated the presence of an actively living community of Thaumarchaeota. Archaeal 16S rRNA clone libraries revealed the presence of thaumarchaeotal groups 1.1a and 1.1b at and above the oxycline. In the anoxic deep water, amoA gene abundance was an order of magnitude lower than at the oxycline and high abundance (∼90 ng l(-1) ) of an IPL with the acyclic glycerol dialkyl glycerol tetraether (GDGT-0) was evident. The predominance of archaeal 16S rRNA sequences affiliated to the uncultured crenarchaeota groups 1.2 and miscellaneous crenarchaeotic group (MCG) points to an origin of GDGT-0 from uncultured crenarchaeota. This study demonstrates the importance of thermal stratification and nutrient availability in the distribution of archaeal groups in lakes, which is relevant to constrain and validate temperature proxies based on archaeal GDGTs (i.e. TEX86 ). © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

  15. The Role of Tetraether Lipid Composition in the Adaptation of Thermophilic Archaea to Acidity

    Directory of Open Access Journals (Sweden)

    Eric eBoyd

    2013-04-01

    Full Text Available Diether and tetraether lipids are fundamental components of the archaeal cell membrane. Archaea adjust the degree of tetraether lipid cyclization in order to maintain functional membranes and cellular homeostasis when confronted with pH and/or thermal stress. Thus, the ability to adjust tetraether lipid composition likely represents a critical phenotypic trait that enabled archaeal diversification into environments characterized by extremes in pH and/or temperature. Here we assess the relationship between geochemical variation, core- and polar-isoprenoid glycerol dibiphytanyl glycerol tetraether (C-iGDGT and P-iGDGT, respectively lipid composition, and archaeal 16S rRNA gene diversity and abundance in 27 geothermal springs in Yellowstone National Park (YNP, Wyoming. The composition and abundance of C-iGDGT and P-iGDGT lipids recovered from geothermal ecosystems were distinct from surrounding soils, indicating that they are synthesized endogenously. With the exception of GDGT-0 (no cyclopentyl rings, the abundances of individual C-iGDGT and P-iGDGT lipids were significantly correlated. The abundance of a number of individual tetraether lipids varied positively with the relative abundance of individual 16S rRNA gene sequences, most notably crenarchaeol in both the core and polar GDGT fraction and sequences closely affiliated with Candidatus Nitrosocaldus yellowstonii. This finding supports the proposal that crenarchaeol is a biomarker for nitrifying archaea. Variation in the degree of cyclization of C- and P-iGDGT lipids recovered from geothermal mats and sediments could best be explained by variation in spring pH, with lipids from acidic environments tending to have, on average, more internal cyclic rings than those from higher pH ecosystems. Likewise, variation in the phylogenetic composition of archaeal 16S rRNA genes could best be explained by spring pH. In turn, the phylogenetic similarity of archaeal 16S rRNA genes was significantly

  16. Relative abundance of Delta(5)-sterols in plasma membrane lipids of root-tip cells correlates with aluminum tolerance of rice.

    Science.gov (United States)

    Khan, M Shahadat Hossain; Tawaraya, Keitarou; Sekimoto, Hiroshi; Koyama, Hiroyuki; Kobayashi, Yuriko; Murayama, Tetsuya; Chuba, Masaru; Kambayashi, Mihoko; Shiono, Yoshihito; Uemura, Matsuo; Ishikawa, Satoru; Wagatsuma, Tadao

    2009-01-01

    We investigated variations in aluminum (Al) tolerance among rice plants, using ancestor cultivars from the family line of the Al-tolerant and widely cultivated Japonica cultivar, Sasanishiki. The cultivar Rikuu-20 was Al sensitive, whereas a closely related cultivar that is a descendant of Rikuu-20, Rikuu-132, was Al tolerant. These two cultivars were compared to determine mechanisms underlying variations in Al tolerance. The sensitive cultivar Rikuu-20 showed increased permeability of the plasma membrane (PM) and greater Al uptake within 1 h of Al treatment. This could not be explained by organic acid release. Lipid composition of the PM differed between these cultivars, and may account for the difference in Al tolerance. The tolerant cultivar Rikuu-132 had a lower ratio of phospholipids to Delta(5)-sterols than the sensitive cultivar Rikuu-20, suggesting that the PM of Rikuu-132 is less negatively charged and less permeabilized than that of Rikuu-20. We used inhibitors of Delta(5)-sterol synthesis to alter the ratio of phospholipids to Delta(5)-sterols in both cultivars. These inhibitors reduced Al tolerance in Rikuu-132 and its Al-tolerant ancestor cultivars Kamenoo and Kyoku. In addition, Rikuu-132 showed a similar level of Al sensitivity when the ratio of phospholipids to Delta(5)-sterols was increased to match that of Rikuu-20 after treatment with uniconazole-P, an inhibitor of obtusifoliol-14alpha-demethylase. These results indicate that PM lipid composition is a factor underlying variations in Al tolerance among rice cultivars.

  17. Endogenous Receptor Agonists: Resolving Inflammation

    Directory of Open Access Journals (Sweden)

    Gerhard Bannenberg

    2007-01-01

    Full Text Available Controlled resolution or the physiologic resolution of a well-orchestrated inflammatory response at the tissue level is essential to return to homeostasis. A comprehensive understanding of the cellular and molecular events that control the termination of acute inflammation is needed in molecular terms given the widely held view that aberrant inflammation underlies many common diseases. This review focuses on recent advances in the understanding of the role of arachidonic acid and ω-3 polyunsaturated fatty acids (PUFA–derived lipid mediators in regulating the resolution of inflammation. Using a functional lipidomic approach employing LC-MS-MS–based informatics, recent studies, reviewed herein, uncovered new families of local-acting chemical mediators actively biosynthesized during the resolution phase from the essential fatty acids eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA. These new families of local chemical mediators are generated endogenously in exudates collected during the resolution phase, and were coined resolvins and protectins because specific members of these novel chemical families control both the duration and magnitude of inflammation in animal models of complex diseases. Recent advances on the biosynthesis, receptors, and actions of these novel anti-inflammatory and proresolving lipid mediators are reviewed with the aim to bring to attention the important role of specific lipid mediators as endogenous agonists in inflammation resolution.

  18. Endogenous Lunar Volatiles

    Science.gov (United States)

    McCubbin, F. M.; Liu, Y.; Barnes, J. J.; Anand, M.; Boyce, J. W.; Burney, D.; Day, J. M. D.; Elardo, S. M.; Hui, H.; Klima, R. L.; Magna, T.; Ni, P.; Steenstra, E.; Tartèse, R.; Vander Kaaden, K. E.

    2018-04-01

    This abstract discusses numerous outstanding questions on the topic of endogenous lunar volatiles that will need to be addressed in the coming years. Although substantial insights into endogenous lunar volatiles have been gained, more work remains.

  19. Endogenous retrovirus sequences expressed in male mammalian ...

    African Journals Online (AJOL)

    In humans, one ERV family, human endogenous retrovirus- K (HERV-K) is abundantly expressed, and is associated with germ cell tumours, while ERV3 env is expressed in normal human testis. Conclusion: The expression of ERVs in male reproductive tissues suggests a possible role in normal and disease conditions ...

  20. Methylated DNA Immunoprecipitation Analysis of Mammalian Endogenous Retroviruses.

    Science.gov (United States)

    Rebollo, Rita; Mager, Dixie L

    2016-01-01

    Endogenous retroviruses are repetitive sequences found abundantly in mammalian genomes which are capable of modulating host gene expression. Nevertheless, most endogenous retrovirus copies are under tight epigenetic control via histone-repressive modifications and DNA methylation. Here we describe a common method used in our laboratory to detect, quantify, and compare mammalian endogenous retrovirus DNA methylation. More specifically we describe methylated DNA immunoprecipitation (MeDIP) followed by quantitative PCR.

  1. Autism Spectrum Disorders May Be Due to Cerebral Toxoplasmosis Associated with Chronic Neuroinflammation Causing Persistent Hypercytokinemia that Resulted in an Increased Lipid Peroxidation, Oxidative Stress, and Depressed Metabolism of Endogenous and Exogenous Substances

    Science.gov (United States)

    Prandota, Joseph

    2010-01-01

    Worldwide, approximately 2 billion people are chronically infected with "Toxoplasma gondii" with largely yet unknown consequences. Patients with autism spectrum disorders (ASD) similarly as mice with chronic toxoplasmosis have persistent neuroinflammation, hypercytokinemia with hypermetabolism associated with enhanced lipid peroxidation, and…

  2. The dynamic of lipid oxidation in human myotubes

    DEFF Research Database (Denmark)

    Gaster, Michael

    2009-01-01

    Both endogenous and exogenous lipid levels may be regulators of total lipid oxidation in skeletal muscles. We studied the dynamics of lipid oxidation in human myotubes established from healthy, lean subjects exposed to acutely and chronically increased palmitate concentrations. The intramyocellular...... triacylglycerol content increased with chronic palmitate exposure. Both, ectopically increased intracellular and extracellular lipid levels were simultaneously oxidized and could partly suppress each other's oxidation. Overall, the highest acute palmitate treatments stimulated fatty acid oxidation whilst...... the highest chronic treatments decreased total lipid oxidation. Intracellular lipids showed a more complete oxidation than exogenous lipids. Endogenous lipids reduced insulin-mediated glucose oxidation. Thus, both endogenous and exogenous lipid concentrations regulated each other's oxidation and total lipid...

  3. Endogenous Prospect Theory

    OpenAIRE

    Schmidt, Ulrich; Zank, Horst

    2010-01-01

    In previous models of (cumulative) prospect theory reference-dependence of preferences is imposed beforehand and the location of the reference point is exogenously determined. This paper provides an axiomatization of a new specification of cumulative prospect theory, termed endogenous prospect theory, where reference-dependence is derived from preference conditions and a unique reference point arises endogenously.

  4. Are endogenous feline leukemia viruses really endogenous?

    Science.gov (United States)

    Stewart, H; Jarrett, O; Hosie, M J; Willett, B J

    2011-10-15

    Full length endogenous feline leukemia virus (FeLV) proviruses exist within the genomes of many breeds of domestic cat raising the possibility that they may also exist in a transmissible exogenous form. Such viruses would share receptor usage with the recombinant FeLV-B subgroup, a viral subgroup that arises in vivo by recombination between exogenous subgroup A virus (FeLV-A) and endogenous FeLV. Accordingly, all isolates of FeLV-B made to date have contained a "helper" FeLV-A, consistent with their recombinatorial origin. In order to assess whether endogenous viruses are transmitted between cats, we examined primary isolates of FeLV for which the viral subgroup had been determined for the presence of a subgroup B virus that lacked an FeLV-A. Here we describe the identification of two primary field isolates of FeLV (2518 and 4314) that appeared to contain subgroup B virus only by classical interference assays, raising the possibility of between-host transmission of endogenous FeLV. Sequencing of the env gene and U3 region of the 3' long terminal repeat (LTR) confirmed that both viral genomes contained endogenous viral env genes. However the viral 3' LTRs appeared exogenous in origin with a putative 3' recombination breakpoint residing at the 3' end of the env gene. Further, the FeLV-2518 virions also co-packaged a truncated FeLV-A genome containing a defective env gene, termed FeLV-2518(A) whilst no helper subgroup A viral genome was detected in virions of FeLV-4314. The acquisition of an exogenous LTR by the endogenous FeLV in 4314 may have allowed a recombinant FeLV variant to outgrow an exogenous FeLV-A virus that was presumably present during first infection. Given time, a similar evolution may also occur within the 2518 isolate. The data suggest that endogenous FeLVs may be mobilised by acquisition of exogenous LTRs yielding novel viruses that type biologically as FeLV-B. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Endogenous Locus Reporter Assays.

    Science.gov (United States)

    Liu, Yaping; Hermes, Jeffrey; Li, Jing; Tudor, Matthew

    2018-01-01

    Reporter gene assays are widely used in high-throughput screening (HTS) to identify compounds that modulate gene expression. Traditionally a reporter gene assay is built by cloning an endogenous promoter sequence or synthetic response elements in the regulatory region of a reporter gene to monitor transcriptional activity of a specific biological process (exogenous reporter assay). In contrast, an endogenous locus reporter has a reporter gene inserted in the endogenous gene locus that allows the reporter gene to be expressed under the control of the same regulatory elements as the endogenous gene, thus more accurately reflecting the changes seen in the regulation of the actual gene. In this chapter, we introduce some of the considerations behind building a reporter gene assay for high-throughput compound screening and describe the methods we have utilized to establish 1536-well format endogenous locus reporter and exogenous reporter assays for the screening of compounds that modulate Myc pathway activity.

  6. Production of endogenous pyrogen.

    Science.gov (United States)

    Dinarello, C A

    1979-01-01

    The production and release of endogenous pyrogen by the host is the first step in the pathogenesis of fever. Endogenous pyrogen is a low-molecular-weight protein released from phagocytic leukocytes in response to several substances of diverse nature. Some of these agents stimulate production of endogenous pyrogen because they are toxic; others act as antigens and interact with either antibody or sensitized lymphocytes in order to induce its production. Some tumors of macrophage origin produce the molecule spontaneously. Whatever the mechanism involved, endogenous pyrogen is synthesized following transcription of new DNA and translation of mRNA into new protein. Once synthesis is completed, the molecule is released without significant intracellular storage. Recent evidence suggests that following release, molecular aggregates form which are biologically active. In its monomer form, endogenous pyrogen is a potent fever-producing substance and mediates fever by its action on the thermoregulatory center.

  7. The Role of Tetraether Lipid Composition in the Adaptation of Thermophilic Archaea to Acidity

    Science.gov (United States)

    Boyd, Eric S.; Hamilton, Trinity L.; Wang, Jinxiang; He, Liu; Zhang, Chuanlun L.

    2013-01-01

    Diether and tetraether lipids are fundamental components of the archaeal cell membrane. Archaea adjust the degree of tetraether lipid cyclization in order to maintain functional membranes and cellular homeostasis when confronted with pH and/or thermal stress. Thus, the ability to adjust tetraether lipid composition likely represents a critical phenotypic trait that enabled archaeal diversification into environments characterized by extremes in pH and/or temperature. Here we assess the relationship between geochemical variation, core- and polar-isoprenoid glycerol dibiphytanyl glycerol tetraether (C-iGDGT and P-iGDGT, respectively) lipid composition, and archaeal 16S rRNA gene diversity and abundance in 27 geothermal springs in Yellowstone National Park, Wyoming. The composition and abundance of C-iGDGT and P-iGDGT lipids recovered from geothermal ecosystems were distinct from surrounding soils, indicating that they are synthesized endogenously. With the exception of GDGT-0 (no cyclopentyl rings), the abundances of individual C-iGDGT and P-iGDGT lipids were significantly correlated. The abundance of a number of individual tetraether lipids varied positively with the relative abundance of individual 16S rRNA gene sequences, most notably crenarchaeol in both the core and polar GDGT fraction and sequences closely affiliated with Candidatus Nitrosocaldus yellowstonii. This finding supports the proposal that crenarchaeol is a biomarker for nitrifying archaea. Variation in the degree of cyclization of C- and P-iGDGT lipids recovered from geothermal mats and sediments could best be explained by variation in spring pH, with lipids from acidic environments tending to have, on average, more internal cyclic rings than those from higher pH ecosystems. Likewise, variation in the phylogenetic composition of archaeal 16S rRNA genes could best be explained by spring pH. In turn, the phylogenetic similarity of archaeal 16S rRNA genes was significantly correlated with the similarity

  8. The role of tetraether lipid composition in the adaptation of thermophilic archaea to acidity.

    Science.gov (United States)

    Boyd, Eric S; Hamilton, Trinity L; Wang, Jinxiang; He, Liu; Zhang, Chuanlun L

    2013-01-01

    Diether and tetraether lipids are fundamental components of the archaeal cell membrane. Archaea adjust the degree of tetraether lipid cyclization in order to maintain functional membranes and cellular homeostasis when confronted with pH and/or thermal stress. Thus, the ability to adjust tetraether lipid composition likely represents a critical phenotypic trait that enabled archaeal diversification into environments characterized by extremes in pH and/or temperature. Here we assess the relationship between geochemical variation, core- and polar-isoprenoid glycerol dibiphytanyl glycerol tetraether (C-iGDGT and P-iGDGT, respectively) lipid composition, and archaeal 16S rRNA gene diversity and abundance in 27 geothermal springs in Yellowstone National Park, Wyoming. The composition and abundance of C-iGDGT and P-iGDGT lipids recovered from geothermal ecosystems were distinct from surrounding soils, indicating that they are synthesized endogenously. With the exception of GDGT-0 (no cyclopentyl rings), the abundances of individual C-iGDGT and P-iGDGT lipids were significantly correlated. The abundance of a number of individual tetraether lipids varied positively with the relative abundance of individual 16S rRNA gene sequences, most notably crenarchaeol in both the core and polar GDGT fraction and sequences closely affiliated with Candidatus Nitrosocaldus yellowstonii. This finding supports the proposal that crenarchaeol is a biomarker for nitrifying archaea. Variation in the degree of cyclization of C- and P-iGDGT lipids recovered from geothermal mats and sediments could best be explained by variation in spring pH, with lipids from acidic environments tending to have, on average, more internal cyclic rings than those from higher pH ecosystems. Likewise, variation in the phylogenetic composition of archaeal 16S rRNA genes could best be explained by spring pH. In turn, the phylogenetic similarity of archaeal 16S rRNA genes was significantly correlated with the similarity

  9. Lipid Neuroprotectants and Traumatic Glaucomatous Neurodegeneration

    Science.gov (United States)

    2016-05-01

    not in individuals suffering from glaucoma (endogenous lipids ). The proposed research is to develop several such lipids as potential glaucoma...The proposed research will further assess the efficacy of the new lipids to lower IOP using mouse and monkeys that can develop glaucoma naturally or...of seminars and posters. Two high school students during summer (as part of their HHMI research program) learned hands-on about lipid analyses. A

  10. Challenges in testing genetically modified crops for potential increases in endogenous allergen expression for safety.

    Science.gov (United States)

    Panda, R; Ariyarathna, H; Amnuaycheewa, P; Tetteh, A; Pramod, S N; Taylor, S L; Ballmer-Weber, B K; Goodman, R E

    2013-02-01

    Premarket, genetically modified (GM) plants are assessed for potential risks of food allergy. The major risk would be transfer of a gene encoding an allergen or protein nearly identical to an allergen into a different food source, which can be assessed by specific serum testing. The potential that a newly expressed protein might become an allergen is evaluated based on resistance to digestion in pepsin and abundance in food fractions. If the modified plant is a common allergenic source (e.g. soybean), regulatory guidelines suggest testing for increases in the expression of endogenous allergens. Some regulators request evaluating endogenous allergens for rarely allergenic plants (e.g. maize and rice). Since allergic individuals must avoid foods containing their allergen (e.g. peanut, soybean, maize, or rice), the relevance of the tests is unclear. Furthermore, no acceptance criteria are established and little is known about the natural variation in allergen concentrations in these crops. Our results demonstrate a 15-fold difference in the major maize allergen, lipid transfer protein between nine varieties, and complex variation in IgE binding to various soybean varieties. We question the value of evaluating endogenous allergens in GM plants unless the intent of the modification was production of a hypoallergenic crop. © 2012 John Wiley & Sons A/S.

  11. Endogenous Pyrogen Physiology.

    Science.gov (United States)

    Beisel, William R.

    1980-01-01

    Discusses the physiology of endogenous pyrogen (EP), the fever-producing factor of cellular origin. Included are: its hormone-like role, its molecular nature, bioassay procedures, cellular production and mechanisms of EP action. (SA)

  12. Cytokines as endogenous pyrogens.

    Science.gov (United States)

    Dinarello, C A

    1999-03-01

    Cytokines are pleiotropic molecules mediating several pathologic processes. Long before the discovery of cytokines as immune system growth factors or as bone marrow stimulants, investigators learned a great deal about cytokines when they studied them as the endogenous mediators of fever. The terms "granulocytic" or "endogenous pyrogen" were used to describe substances with the biologic property of fever induction. Today, we recognize that pyrogenicity is a fundamental biologic property of several cytokines and hence the clinically recognizeable property of fever links host perturbations during disease with fundamental perturbations in cell biology. In this review, the discoveries made on endogenous pyrogens are revisited, with insights into the importance of the earlier work to the present-day understanding of cytokines in health and in disease.

  13. Scallop protein with endogenous high taurine and glycine content prevents high-fat, high-sucrose-induced obesity and improves plasma lipid profile in male C57BL/6J mice

    DEFF Research Database (Denmark)

    Tastesen, Hanne Sørup; Keenan, Alison H.; Madsen, Lise

    2014-01-01

    High-protein diets induce alterations in metabolism that may prevent diet-induced obesity. However, little is known as to whether different protein sources consumed at normal levels may affect diet-induced obesity and associated co-morbidities. We fed obesity-prone male C57BL/6J mice high-fat, high......-fed mice, but otherwise no changes in lean body mass were observed between the groups. Feed efficiency and apparent nitrogen digestibility were reduced in scallop-fed mice suggesting alterations in energy utilization and metabolism. Overnight fasted plasma triacylglyceride, non-esterified fatty acids......, glycerol and hydroxy-butyrate levels were significantly reduced, indicating reduced lipid mobilization in scallop-fed mice. The plasma HDL-to-total-cholesterol ratio was higher, suggesting increased reverse cholesterol transport or cholesterol clearance in scallop-fed mice in both fasted and non-fasted...

  14. Evolution of endogenous analgesia

    NARCIS (Netherlands)

    Niesters, Marieke

    2014-01-01

    Endogenous pain modulation is a complex phenomenon involved in the perception of pain. It consists of top-down inhibitory and facilitatory pathways that originate at higher sites within the central nervous system and converge at dorsal horn neurons in the spinal cord, to modulate incoming afferent

  15. Unemployment and endogenous growth

    NARCIS (Netherlands)

    van Schaik, A.B.T.M.; de Groot, H.L.F.

    1995-01-01

    In this paper we develop a two-sector endogenous growth model with a dual labour market, based on efficiency wages. Growth is driven by intentional R&D performed in the high-tech and high-wage sector. It is examined how a change in rivalry among firms affects simultaneously growth and unemployment.

  16. Endogenous growth and the environment

    NARCIS (Netherlands)

    Withagen, C.A.A.M.; Vellinga, N.

    2001-01-01

    This paper examines the relationship between environmental policy and growth, from the perspective of endogenous growth theory. In particular three standard endogenous growth models are supplemented with environmental issues, such as pollution and exhaustibility of natural resources. It is found

  17. Endogenous growth and environmental policy

    NARCIS (Netherlands)

    Withagen, C.A.A.M.; Vellinga, N.

    2001-01-01

    This paper examines the relationship between environmental policy and growth, from the perspective of endogenous growth theory. In particular three standard endogenous growth models are supplemented with environmental issues, such as pollution and exhaustibility of natural resources. It is found

  18. Stimulating endogenous cardiac regeneration

    Directory of Open Access Journals (Sweden)

    Amanda eFinan

    2015-09-01

    Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

  19. Exogenous vs. Endogenous Separation

    OpenAIRE

    Ramey, Garey

    2008-01-01

    This paper assesses how various approaches to modelling the separation margin a¤ect the ability of the Mortensen-Pissarides job matching model to explain key facts about the aggregate labor market. Allowing for realistic time variation in the separation rate, whether exogenous or endogenous, greatly in- creases the unemployment variability generated by the model. Speci…cations with exogenous separation rates, whether constant or time-varying, fail to pro- duce realistic volatility and prod...

  20. Inhibition of human pancreatic and biliary output but not intestinal motility by physiological intraileal lipid loads

    DEFF Research Database (Denmark)

    Keller, Jutta; Holst, Jens Juul; Layer, Peter

    2005-01-01

    Lipid perfusion into the distal ileal lumen at supraphysiological loads inhibits pancreatic exocrine secretion and gastrointestinal motility in humans. In the present study, we sought to determine the effects of physiological postprandial intraileal lipid concentrations on endogenously stimulated...

  1. Endogenous sphingomyelin segregates into submicrometric domains in the living erythrocyte membrane[S

    Science.gov (United States)

    Carquin, Mélanie; Pollet, Hélène; Veiga-da-Cunha, Maria; Cominelli, Antoine; Van Der Smissen, Patrick; N’kuli, Francisca; Emonard, Hervé; Henriet, Patrick; Mizuno, Hideaki; Courtoy, Pierre J.; Tyteca, Donatienne

    2014-01-01

    We recently reported that trace insertion of exogenous fluorescent (green BODIPY) analogs of sphingomyelin (SM) into living red blood cells (RBCs), partially spread onto coverslips, labels submicrometric domains, visible by confocal microscopy. We here extend this feature to endogenous SM, upon binding of a SM-specific nontoxic (NT) fragment of the earthworm toxin, lysenin, fused to the red monomeric fluorescent protein, mCherry [construct named His-mCherry-NT-lysenin (lysenin*)]. Specificity of lysenin* binding was verified with composition-defined liposomes and by loss of 125I-lysenin* binding to erythrocytes upon SM depletion by SMase. The 125I-lysenin* binding isotherm indicated saturation at 3.5 × 106 molecules/RBC, i.e., ∼3% of SM coverage. Nonsaturating lysenin* concentration also labeled sub­micrometric domains on the plasma membrane of partially spread erythrocytes, colocalizing with inserted green BODIPY-SM, and abrogated by SMase. Lysenin*-labeled domains were stable in time and space and were regulated by temperature and cholesterol. The abundance, size, positioning, and segregation of lysenin*-labeled domains from other lipids (BODIPY-phosphatidylcholine or -glycosphingolipids) depended on membrane tension. Similar lysenin*-labeled domains were evidenced in RBCs gently suspended in 3D-gel. Taken together, these data demonstrate submicrometric compartmentation of endogenous SM at the membrane of a living cell in vitro, and suggest it may be a genuine feature of erythrocytes in vivo. PMID:24826836

  2. Dermal extracellular lipid in birds.

    Science.gov (United States)

    Stromberg, M W; Hinsman, E J; Hullinger, R L

    1990-01-01

    A light and electron microscopic study of the skin of domestic chickens, seagulls, and antarctic penguins revealed abundant extracellular dermal lipid and intracellular epidermal lipid. Dermal lipid appeared ultrastructurally as extracellular droplets varying from less than 1 micron to more than 25 microns in diameter. The droplets were often irregularly contoured, sometimes round, and of relatively low electron density. Processes of fibrocytes were often seen in contact with extracellular lipid droplets. Sometimes a portion of such a droplet was missing, and this missing part appeared to have been "digested away" by the cell process. In places where cells or cell processes are in contact with fact droplets, there are sometimes extracellular membranous whorls or fragments which have been associated with the presence of fatty acids. Occasionally (in the comb) free fat particles were seen in intimate contact with extravasated erythrocytes. Fat droplets were seen in the lumen of small dermal blood and lymph vessels. We suggest that the dermal extracellular lipid originates in the adipocyte layer and following hydrolysis the free fatty acids diffuse into the epidermis. Here they become the raw material for forming the abundant neutral lipid contained in many of the epidermal cells of both birds and dolphins. The heretofore unreported presence and apparently normal utilization of abundant extracellular lipid in birds, as well as the presence of relatively large droplets of neutral lipid in dermal vessels, pose questions which require a thorough reappraisal of present concepts of the ways in which fat is distributed and utilized in the body.

  3. Fanconi anemia proteins and endogenous stresses

    Energy Technology Data Exchange (ETDEWEB)

    Pang Qishen [Division of Experimental Hematology and Cancer Biology, Cincinnati Children' s Research Foundation, Cincinnati, OH (United States); Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH (United States); Andreassen, Paul R., E-mail: Paul.Andreassen@cchmc.org [Division of Experimental Hematology and Cancer Biology, Cincinnati Children' s Research Foundation, Cincinnati, OH (United States); Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH (United States)

    2009-07-31

    Each of the thirteen identified Fanconi anemia (FA) genes is required for resistance to DNA interstrand crosslinking agents, such as mitomycin C, cisplatin, and melphalan. While these agents are excellent tools for understanding the function of FA proteins in DNA repair, it is uncertain whether a defect in the removal of DNA interstrand crosslinks (ICLs) is the basis for the pathophysiology of FA. For example, DNA interstrand crosslinking agents induce other types of DNA damage, in addition to ICLs. Further, other DNA-damaging agents, such as ionizing or ultraviolet radiation, activate the FA pathway, leading to monoubiquitination of FANCD2 and FANCI. Also, FA patients display congenital abnormalities, hematologic deficiencies, and a predisposition to cancer in the absence of an environmental source of ICLs that is external to cells. Here we consider potential sources of endogenous DNA damage, or endogenous stresses, to which FA proteins may respond. These include ICLs formed by products of lipid peroxidation, and other forms of oxidative DNA damage. FA proteins may also potentially respond to telomere shortening or replication stress. Defining these endogenous sources of DNA damage or stresses is critical for understanding the pathogenesis of deficiencies for FA proteins. We propose that FA proteins are centrally involved in the response to replication stress, including replication stress arising from oxidative DNA damage.

  4. Fanconi anemia proteins and endogenous stresses

    International Nuclear Information System (INIS)

    Pang Qishen; Andreassen, Paul R.

    2009-01-01

    Each of the thirteen identified Fanconi anemia (FA) genes is required for resistance to DNA interstrand crosslinking agents, such as mitomycin C, cisplatin, and melphalan. While these agents are excellent tools for understanding the function of FA proteins in DNA repair, it is uncertain whether a defect in the removal of DNA interstrand crosslinks (ICLs) is the basis for the pathophysiology of FA. For example, DNA interstrand crosslinking agents induce other types of DNA damage, in addition to ICLs. Further, other DNA-damaging agents, such as ionizing or ultraviolet radiation, activate the FA pathway, leading to monoubiquitination of FANCD2 and FANCI. Also, FA patients display congenital abnormalities, hematologic deficiencies, and a predisposition to cancer in the absence of an environmental source of ICLs that is external to cells. Here we consider potential sources of endogenous DNA damage, or endogenous stresses, to which FA proteins may respond. These include ICLs formed by products of lipid peroxidation, and other forms of oxidative DNA damage. FA proteins may also potentially respond to telomere shortening or replication stress. Defining these endogenous sources of DNA damage or stresses is critical for understanding the pathogenesis of deficiencies for FA proteins. We propose that FA proteins are centrally involved in the response to replication stress, including replication stress arising from oxidative DNA damage.

  5. A lipid binding domain in sphingosine kinase 2

    International Nuclear Information System (INIS)

    Don, Anthony S.; Rosen, Hugh

    2009-01-01

    The lipid second messenger sphingosine 1-phosphate (S1P) is a critical mediator of cellular proliferation and survival signals, and is essential for vasculogenesis and neurogenesis. S1P formation is catalysed by sphingosine kinases 1 and 2 (Sphk1 and Sphk2). We have found that the endogenous glycolipid sulfatide (3-O-sulfogalactosylceramide) binds to and inhibits the activity of Sphk2 and the closely related ceramide kinase (Cerk), but not Sphk1. Using sulfatide as a probe, we mapped the lipid binding domain to the N-terminus of Sphk2 (residues 1-175), a region of sequence that is absent in Sphk1, but aligns with a pleckstrin homology domain in Cerk. Accordingly, Sphk2 bound to phosphatidylinositol monophosphates but not to abundant cellular phospholipids. Deleting the N-terminal domain reduced Sphk2 membrane localisation in cells. We have therefore identified a lipid binding domain in Sphk2 that is important for the enzyme's sub-cellular localisation.

  6. The Endogenous Feedback Network

    DEFF Research Database (Denmark)

    Augustenborg, Claudia Carrara

    2010-01-01

    proposals, it will first be considered the extents of their reciprocal compatibility, tentatively shaping an integrated, theoretical profile of consciousness. A new theory, the Endogenous Feedback Network (EFN) will consequently be introduced which, beside being able to accommodate the main tenets...... of the reviewed theories, appears able to compensate for the explanatory gaps they leave behind. The EFN proposes consciousness as the phenomenon emerging from a distinct network of neural paths broadcasting the neural changes associated to any mental process. It additionally argues for the need to include a 5th...

  7. Hume and Endogenous Money

    OpenAIRE

    Maria Pia Paganelli

    2006-01-01

    David Hume’s monetary theory has three standard yet inconsistent readings. As a forefather of the quantity theory of money, Hume sees money as neutral. As an inflationist, Hume sees an active positive role for monetary policy. As a monetarist, Hume sees an active positive role for monetary policy only in the short run. This paper reads Hume consistently instead by showing that for Hume money is endogenous and demand-driven. Hume would read the money equation in terms of reverse causation and ...

  8. Combining Semi-Endogenous and Fully Endogenous Growth: a Generalization.

    OpenAIRE

    Cozzi, Guido

    2017-01-01

    This paper shows that combining the semi-endogenous and the fully endogenous growth mechanisms with a general CES aggregator, either growth process can prevail in the balanced growth path depending on their degree of complementarity/substitutability. Policy-induced long-run economic switches to the fully endogenous steady state as the R&D employment ratio surpasses a positive threshold are possible if the two growth engines are gross substitutes.

  9. Endogenous Retroviruses in the Genomics Era.

    Science.gov (United States)

    Johnson, Welkin E

    2015-11-01

    Endogenous retroviruses comprise millions of discrete genetic loci distributed within the genomes of extant vertebrates. These sequences, which are clearly related to exogenous retroviruses, represent retroviral infections of the deep past, and their abundance suggests that retroviruses were a near-constant presence throughout the evolutionary history of modern vertebrates. Endogenous retroviruses contribute in myriad ways to the evolution of host genomes, as mutagens and as sources of genetic novelty (both coding and regulatory) to be acted upon by the twin engines of random genetic drift and natural selection. Importantly, the richness and complexity of endogenous retrovirus data can be used to understand how viruses spread and adapt on evolutionary timescales by combining population genetics and evolutionary theory with a detailed understanding of retrovirus biology (gleaned from the study of extant retroviruses). In addition to revealing the impact of viruses on organismal evolution, such studies can help us better understand, by looking back in time, how life-history traits, as well as ecological and geological events, influence the movement of viruses within and between populations.

  10. ENDOGENEITY OF INDONESIAN MONEY SUPPLY

    OpenAIRE

    Rachma, Meutia Safrina

    2011-01-01

    There has been a long debate about the endogeneity of money supply. The main objective of this article is to identify whether money supply in Indonesia is an exogenous or an endogenous variable. Using a Vector Autoregressive model and monthly data 1997(5)-2010(6), the estimation result shows that money supply in Indonesia is an endogenous variable. The movement of broad money supply does influence the movement of base money and Consumer Price Index. Consequently, the central bank does not hav...

  11. Endogeneity Of Indonesian Money Supply

    OpenAIRE

    Rachma, Meutia Safrina

    2010-01-01

    There has been a long debate about the endogeneity of money supply. The main objective of this article is to identify whether money supply in Indonesia is an exogenous or an endogenous variable. Using a Vector Autoregressive model and monthly data 1997(5)-2010(6), the estimation result shows that money supply in Indonesia is an endogenous variable. The movement of broad money supply does influence the movement of base money and Consumer Price Index. Consequently, the central bank does not hav...

  12. Habits, aspirations and endogenous fertility

    OpenAIRE

    Luciano Fanti

    2012-01-01

    Motivated by the increasing literature on endogenous preferences as well as on endogenous fertility, this paper investigates the implications of the interaction of the endogenous determination of the number of children with habit and aspiration formation in an OLG model. In contrast with the previous literature, we show that greater aspirations may lead to higher savings, and more interestingly, always increase the neoclassical economic growth.

  13. Endogenous Monetary Policy Regime Change

    OpenAIRE

    Troy Davig; Eric M. Leeper

    2006-01-01

    This paper makes changes in monetary policy rules (or regimes) endogenous. Changes are triggered when certain endogenous variables cross specified thresholds. Rational expectations equilibria are examined in three models of threshold switching to illustrate that (i) expectations formation effects generated by the possibility of regime change can be quantitatively important; (ii) symmetric shocks can have asymmetric effects; (iii) endogenous switching is a natural way to formally model preempt...

  14. Lipid storage myopathies.

    Science.gov (United States)

    Bruno, Claudio; Dimauro, Salvatore

    2008-10-01

    The aim of this review is to provide an update on disorders of lipid metabolism affecting skeletal muscle exclusively or predominantly and to summarize recent clinical, genetic, and therapeutic studies in this field. Over the past 5 years, new clinical phenotypes and genetic loci have been described, unusual pathogenic mechanisms have been elucidated, and novel pharmacological approaches have been developed. At least one genetic defect responsible for the myopathic form of CoQ10 deficiency has been identified, causing a disorder that is allelic with the late-onset riboflavine-responsive form of multiple acyl-coenzyme A dehydrogenation deficiency. Novel mechanisms involved in the lipolytic breakdown of cellular lipid depots have been described and have led to the identification of genes and mutations responsible for multisystemic neutral lipid storage disorders, characterized by accumulation of triglyceride in multiple tissues, including muscle. Defects in lipid metabolism can affect either the mitochondrial transport and oxidation of exogenous fatty acid or the catabolism of endogenous triglycerides. These disorders impair energy production and almost invariably involve skeletal muscle, causing progressive myopathy with muscle weakness, or recurrent acute episodes of rhabdomyolysis triggered by exercise, fasting, or infections. Clinical and genetic characterization of these disorders has important implications both for accurate diagnostic approach and for development of therapeutic strategies.

  15. Endogenous fertility and development traps with endogenous lifetime

    OpenAIRE

    Fanti, Luciano; Gori, Luca

    2010-01-01

    We extend the literature on endogenous lifetime and economic growth by Chakraborty (2004) and Bunzel and Qiao (2005) to endogenous fertility. We show that development traps due to underinvestments in health cannot appear when fertility is an economic decision variable and the costs of children are represented by a constant fraction of the parents' income used for their upbringing.

  16. From Leaf Synthesis to Senescence: n-Alkyl Lipid Abundance and D/H Composition Among Plant Species in a Temperate Deciduous Forest at Brown's Lake Bog, Ohio, USA

    Science.gov (United States)

    Freimuth, E. J.; Diefendorf, A. F.; Lowell, T. V.

    2014-12-01

    The hydrogen isotope composition (D/H, δD) of terrestrial plant leaf waxes is a promising paleohydrology proxy because meteoric water (e.g., precipitation) is the primary hydrogen source for wax synthesis. However, secondary environmental and biological factors modify the net apparent fractionation between precipitation δD and leaf wax δD, limiting quantitative reconstruction of paleohydrology. These secondary factors include soil evaporation, leaf transpiration, biosynthetic fractionation, and the seasonal timing of lipid synthesis. Here, we investigate the influence of each of these factors on n-alkyl lipid δD in five dominant deciduous angiosperm tree species as well as shrubs, ferns and grasses in the watershed surrounding Brown's Lake Bog, Ohio, USA. We quantified n-alkane and n-alkanoic acid concentrations and δD in replicate individuals of each species at weekly to monthly intervals from March to October 2014 to assess inter- and intraspecific isotope variability throughout the growing season. We present soil, xylem and leaf water δD from each individual, and precipitation and atmospheric water vapor δD throughout the season to directly examine the relationship between source water and lipid isotope composition. These data allow us to assess the relative influence of soil evaporation and leaf transpiration among plant types, within species, and along a soil moisture gradient throughout the catchment. We use leaf water δD to approximate biosynthetic fractionation for each individual and test whether this is a species-specific and seasonal constant, and to evaluate variation among plant types with identical growth conditions. Our high frequency sampling approach provides new insights into the seasonal timing of n-alkane and n-alkanoic acid synthesis and subsequent fluctuations in concentration and δD in a temperate deciduous forest. These results will advance understanding of the magnitude and timing of secondary influences on the modern leaf wax

  17. Endogenous Plasma Peptide Detection and Identification in the Rat by a Combination of Fractionation Methods and Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Fabrice Bertile

    2007-01-01

    Full Text Available Mass spectrometry-based analyses are essential tools in the field of biomarker research. However, detection and characterization of plasma low abundance and/or low molecular weight peptides is challenged by the presence of highly abundant proteins, salts and lipids. Numerous strategies have already been tested to reduce the complexity of plasma samples. The aim of this study was to enrich the low molecular weight fraction of rat plasma. To this end, we developed and compared simple protocols based on membrane filtration, solid phase extraction, and a combination of both. As assessed by UV absorbance, an albumin depletion 99% was obtained. The multistep fractionation strategy (including reverse phase HPLC allowed detection, in a reproducible manner (CV [1] 30%–35%, of more than 450 peaks below 3000 Da by MALDI-TOF/MS. A MALDI-TOF/MS-determined LOD as low as 1 fmol/μL was obtained, thus allowing nanoLC-Chip/ MS/MS identification of spiked peptides representing ∼10–6% of total proteins, by weight. Signal peptide recovery ranged between 5%–100% according to the spiked peptide considered. Tens of peptide sequence tags from endogenous plasma peptides were also obtained and high confidence identifications of low abundance fibrinopeptide A and B are reported here to show the efficiency of the protocol. It is concluded that the fractionation protocol presented would be of particular interest for future differential (high throughput analyses of the plasma low molecular weight fraction.

  18. Lipid somersaults

    DEFF Research Database (Denmark)

    Günther-Pomorski, Thomas; Menon, Anant K.

    2016-01-01

    Membrane lipids diffuse rapidly in the plane of the membrane but their ability to flip spontaneously across a membrane bilayer is hampered by a significant energy barrier. Thus spontaneous flip-flop of polar lipids across membranes is very slow, even though it must occur rapidly to support diverse...... aspects of cellular life. Here we discuss the mechanisms by which rapid flip-flop occurs, and what role lipid flipping plays in membrane homeostasis and cell growth. We focus on conceptual aspects, highlighting mechanistic insights from biochemical and in silico experiments, and the recent, ground......-breaking identification of a number of lipid scramblases....

  19. Reduced lipid oxidation in myotubes established from obese and type 2 diabetic subjects

    DEFF Research Database (Denmark)

    Gaster, Michael

    2009-01-01

    To date, it is unknown whether reduced lipid oxidation of skeletal muscle of obese and obese type 2 diabetic (T2D) subjects partly is based on reduced oxidation of endogenous lipids. Palmitate (PA) accumulation, total oxidation and lipolysis were not different between myotubes established from lean...... both for endogenous and exogenous lipids. Thus myotubes established from obese and obese T2D subjects express a reduced complete oxidation of endogenous lipids. Two cardinal principles govern the reduced lipid oxidation in obese and diabetic myotubes; firstly, an impaired coupling between endogenous...... lipid and mitochondria in obese and obese diabetic myotubes and secondly, a mismatch between beta-oxidation and citric acid cycle in obese diabetic myotubes....

  20. Lipid profiling in sewage sludge.

    Science.gov (United States)

    Zhu, Fenfen; Wu, Xuemin; Zhao, Luyao; Liu, Xiaohui; Qi, Juanjuan; Wang, Xueying; Wang, Jiawei

    2017-06-01

    High value-added reutilization of sewage sludge from wastewater treatment plants (WWTPs) is essential in sustainable development in WWTPs. However, despite the advantage of high value reutilization, this process must be based on a detailed study of organics in sludge. We used the methods employed in life sciences to determine the profile of lipids (cellular lipids, free fatty acids (FFAs), and wax/gum) in five sludge samples obtained from three typical WWTPs in Beijing; these samples include one sludge sample from a primary sedimentation tank, two activated sludge samples from two Anaerobic-Anoxic-Oxic (A2/O) tanks, and two activated sludge samples from two membrane bioreactor tanks. The percentage of total raw lipids varied from 2.90% to 12.3%. Sludge from the primary sedimentation tank showed the highest concentrations of lipid, FFA, and wax/gum and the second highest concentration of cellular lipids. All activated sludge contained an abundance of cellular lipids (>54%). Cells in sludge can from plants, animals, microbes and so on in wastewater. Approximately 14 species of cellular lipids were identified, including considerable high value-potential ceramide (9567-38774 mg/kg), coenzyme (937-3897 mg/kg), and some phosphatidylcholine (75-548 mg/kg). The presence of those lipid constituents would thus require a wider range of recovery methods for sludge. Both cellular lipids and FFAs contain an abundance of C16-C18 lipids at high saturation level, and they serve as good resources for biodiesel production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Preservation of uropygial gland lipids in a 48-million-year-old bird.

    Science.gov (United States)

    O'Reilly, Shane; Summons, Roger; Mayr, Gerald; Vinther, Jakob

    2017-10-25

    Although various kinds of organic molecules are known to occur in fossils and rocks, most soft tissue preservation in animals is attributed to melanin or porphyrins. Lipids are particularly stable over time-as diagenetically altered 'geolipids' or as major molecular constituents of kerogen or fossil 'geopolymers'-and may be expected to be preserved in certain vertebrate tissues. Here we analysed lipid residues from the uropygial gland of an early Eocene bird using pyrolysis gas chromatography mass spectroscopy. We found a pattern of aliphatic molecules in the fossil gland that was distinct from the host oil shale sediment matrix and from feathers of the same fossil. The fossil gland contained abundant n -alkenes, n -alkanes and alkylbenzenes with chain lengths greater than 20, as well as functionalized long-chain aldehydes, ketones, alkylnitriles and alkylthiophenes that were not detected in host sediment or fossil feathers. By comparison with modern bird uropygial gland wax esters, we show that these molecular fossils are likely derived from endogenous wax ester fatty alcohols and fatty acids that survived initial decay and underwent early diagenetic geopolymerization. These data demonstrate the high fidelity preservation of the uropygial gland waxes and showcase the resilience of lipids over geologic time and their potential role in the exceptional preservation of lipid-rich tissues of macrofossils. © 2017 The Author(s).

  2. ENDOGENEITY OF INDONESIAN MONEY SUPPLY

    Directory of Open Access Journals (Sweden)

    Meutia Safrina Rachma

    2011-09-01

    Full Text Available There has been a long debate about the endogeneity of money supply. The main objective of this article is to identify whether money supply in Indonesia is an exogenous or an endogenous variable. Using a Vector Autoregressive model and monthly data 1997(5-2010(6, the estimation result shows that money supply in Indonesia is an endogenous variable. The movement of broad money supply does influence the movement of base money and Consumer Price Index. Consequently, the central bank does not have control power on money supply. The bank is only able to maintain the stability and control the movement of broad money supply. Keywords: Endogenous variable, money supply, vector autoregressionJEL classification numbers: E51, E52, E58

  3. 59 eyes with endogenous endophthalmitis

    DEFF Research Database (Denmark)

    Bjerrum, Søren Solborg; la Cour, Morten

    2017-01-01

    BACKGROUND: To study the epidemiology of patients with endogenous endophthalmitis in Denmark. MATERIAL AND METHODS: Retrospective and prospective case series of 59 eyes in patients with endogenous endophthalmitis in Denmark between 2000 and 2016. RESULTS: The age of the patients ranged from 28 to......, the visual outcome and the mortality of the patients. The epidemiology of the disease is very different in Scandinavia compared to Asia. The visual prognosis remains grave and the majority of the eyes lose useful vision....

  4. Multiple marker abundance profiling

    DEFF Research Database (Denmark)

    Hooper, Cornelia M.; Stevens, Tim J.; Saukkonen, Anna

    2017-01-01

    proteins and the scoring accuracy of lower-abundance proteins in Arabidopsis. NPAS was combined with subcellular protein localization data, facilitating quantitative estimations of organelle abundance during routine experimental procedures. A suite of targeted proteomics markers for subcellular compartment...

  5. Endogenous fishing mortalities: a state-space bioeconomic model

    OpenAIRE

    DA-ROCHA JOSÉ MARIA; GARCÍA-CUTRÍN JAVIER; GUTIÉRREZ MARÍA-JOSÉ; GAMITO JARDIM JOSÉ ERNESTO

    2017-01-01

    A methodology that endogenously determines catchability functions that link fishing mortality with contemporaneous stock abundance is presented. We consider a stochastic age-structured model for a fishery composed by a number of fishing units (fleets, vessels or métiers) that optimally select the level of fishing effort to be applied considering total mortalities as given. The introduction of a balance constrain which guarantees that total mortality is equal to the sum of individual fishing m...

  6. Alkyl caffeates as antioxidants in O/W emulsions: Impact of emulsifier type and endogenous tocopherols

    DEFF Research Database (Denmark)

    Sørensen, Ann-Dorit Moltke; Villeneuve, Pierre; Jacobsen, Charlotte

    2017-01-01

    , the aim was to evaluate the impact of emulsifiers (Citrem and Tween80) and presence of endogenous tocopherols on the efficacies of caffeic acid and caffeates (C1–C20) as antioxidants in emulsions. Lipid oxidation was evaluated during storage and partitioning of caffeic acid and caffeates was estimated...... by measuring their concentrations in the aqueous phase. Partitioning of caffeic acid and caffeates was influenced by emulsifier type and the presence of endogenous tocopherols. Caffeic acid was the most efficient antioxidant in Citrem and Tween stabilized emulsions in the presence of endogenous tocopherol....... In contrast, for Tween stabilized emulsions, caffeic acid acted as a prooxidant and the evaluated caffeates acted as strong antioxidants in the absence of endogenous tocopherol. Thus, when endogenous tocopherol was present lipophilization of caffeic acid did not increase its efficacy as an antioxidant...

  7. Further comparisons of endogenous pyrogens and leukocytic endogenous mediators.

    Science.gov (United States)

    Kampschmidt, R F; Upchurch, H F; Worthington, M L

    1983-07-01

    It was recently shown (Murphy et al., Infect. Immun. 34:177-183), that rabbit macrophages produce two biochemically and immunologically distinct endogenous pyrogens. One of these has or copurifies with substances having a molecular weight of 13,000 and a pI of 7.3. This protein was produced by blood monocytes or inflammatory cells elicited in 16-h rabbit peritoneal exudates. These acute peritoneal exudates were produced by the intraperitoneal injection of large volumes of saline containing shellfish glycogen. When the leukocytes in these exudates were washed and incubated at 37 degrees C in saline, they released an endogenous pyrogen. The injection of this pyrogen into rabbits, rats, or mice caused the biological manifestations which have been attributed to leukocytic endogenous mediator. These effects were increases in blood neutrophils, the lowering of plasma iron and zinc levels, and the increased synthesis of the acute-phase proteins. The other rabbit endogenous pyrogen seems to be a family of proteins with isoelectric points between 4.5 and 5.0. These proteins are produced by macrophages in the lung, liver, or in chronic peritoneal exudates. In these experiments, the lower-isoelectric-point endogenous pyrogens were produced by macrophages from the peritoneal cavity of rabbits that had been injected 4 days earlier with 50 ml of light mineral oil. These rabbit pyrogens were found to have leukocytic endogenous mediator activity in mice but to be completely inactive in rats. When injected into rabbits, these proteins produced fever, lowered plasma iron, increased blood neutrophils, but failed to elevate plasma fibrinogen.

  8. Transcriptional profiling of cells sorted by RNA abundance

    NARCIS (Netherlands)

    Klemm, Sandy; Semrau, Stefan; Wiebrands, Kay; Mooijman, Dylan; Faddah, Dina A; Jaenisch, Rudolf; van Oudenaarden, Alexander

    We have developed a quantitative technique for sorting cells on the basis of endogenous RNA abundance, with a molecular resolution of 10-20 transcripts. We demonstrate efficient and unbiased RNA extraction from transcriptionally sorted cells and report a high-fidelity transcriptome measurement of

  9. On the dependence of speciation rates on species abundance and ...

    Indian Academy of Sciences (India)

    Unknown

    abundance largely determines the rate of generation of intraspecific endogenous genetic variation, the result obtained ... population size together with generation time emerge as important ...... wind and wave mixing of the ocean, any prolonged exis- tence of ..... epipelagic plankton size structure in high latitude oceans; J.

  10. Endogenous System Microbes as Treatment Process ...

    Science.gov (United States)

    Monitoring the efficacy of treatment strategies to remove pathogens in decentralized systems remains a challenge. Evaluating log reduction targets by measuring pathogen levels is hampered by their sporadic and low occurrence rates. Fecal indicator bacteria are used in centralized systems to indicate the presence of fecal pathogens, but are ineffective decentralized treatment process indicators as they generally occur at levels too low to assess log reduction targets. System challenge testing by spiking with high loads of fecal indicator organisms, like MS2 coliphage, has limitations, especially for large systems. Microbes that are endogenous to the decentralized system, occur in high abundances and mimic removal rates of bacterial, viral and/or parasitic protozoan pathogens during treatment could serve as alternative treatment process indicators to verify log reduction targets. To identify abundant microbes in wastewater, the bacterial and viral communities were examined using deep sequencing. Building infrastructure-associated bacteria, like Zoogloea, were observed as dominant members of the bacterial community in graywater. In blackwater, bacteriophage of the order Caudovirales constituted the majority of contiguous sequences from the viral community. This study identifies candidate treatment process indicators in decentralized systems that could be used to verify log removal during treatment. The association of the presence of treatment process indic

  11. Ezetimibe Increases Endogenous Cholesterol Excretion in Humans.

    Science.gov (United States)

    Lin, Xiaobo; Racette, Susan B; Ma, Lina; Wallendorf, Michael; Ostlund, Richard E

    2017-05-01

    Ezetimibe improves cardiovascular outcomes when added to optimum statin treatment. It lowers low-density lipoprotein cholesterol and percent intestinal cholesterol absorption, but the exact cardioprotective mechanism is unknown. We tested the hypothesis that the dominant effect of ezetimibe is to increase the reverse transport of cholesterol from rapidly mixing endogenous cholesterol pool into the stool. In a randomized, placebo-controlled, double-blind parallel trial in 24 healthy subjects with low-density lipoprotein cholesterol 100 to 200 mg/dL, we measured cholesterol metabolism before and after a 6-week treatment period with ezetimibe 10 mg/d or placebo. Plasma cholesterol was labeled by intravenous infusion of cholesterol-d 7 in a lipid emulsion and dietary cholesterol with cholesterol-d 5 and sitostanol-d 4 solubilized in oil. Plasma and stool samples collected during a cholesterol- and phytosterol-controlled metabolic kitchen diet were analyzed by mass spectrometry. Ezetimibe reduced intestinal cholesterol absorption efficiency 30±4.3% (SE, P <0.0001) and low-density lipoprotein cholesterol 19.8±1.9% ( P =0.0001). Body cholesterol pool size was unchanged, but fecal endogenous cholesterol excretion increased 66.6±12.2% ( P <0.0001) and percent cholesterol excretion from body pools into the stool increased 74.7±14.3% ( P <0.0001), whereas plasma cholesterol turnover rose 26.2±3.6% ( P =0.0096). Fecal bile acids were unchanged. Ezetimibe increased the efficiency of reverse cholesterol transport from rapidly mixing plasma and tissue pools into the stool. Further work is needed to examine the potential relation of reverse cholesterol transport and whole body cholesterol metabolism to coronary events and the treatment of atherosclerosis. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01603758. © 2017 American Heart Association, Inc.

  12. Lipid Nanotechnology

    Directory of Open Access Journals (Sweden)

    Gijsje Koenderink

    2013-02-01

    Full Text Available Nanotechnology is a multidisciplinary field that covers a vast and diverse array of devices and machines derived from engineering, physics, materials science, chemistry and biology. These devices have found applications in biomedical sciences, such as targeted drug delivery, bio-imaging, sensing and diagnosis of pathologies at early stages. In these applications, nano-devices typically interface with the plasma membrane of cells. On the other hand, naturally occurring nanostructures in biology have been a source of inspiration for new nanotechnological designs and hybrid nanostructures made of biological and non-biological, organic and inorganic building blocks. Lipids, with their amphiphilicity, diversity of head and tail chemistry, and antifouling properties that block nonspecific binding to lipid-coated surfaces, provide a powerful toolbox for nanotechnology. This review discusses the progress in the emerging field of lipid nanotechnology.

  13. Monopoly Insurance and Endogenous Information

    DEFF Research Database (Denmark)

    Lagerlöf, Johan N. M.; Schottmüller, Christoph

    2018-01-01

    We study a monopoly insurance model with endogenous information acquisi- tion. Through a continuous effort choice, consumers can determine the precision of a privately observed signal that is informative about their accident risk. The equilibrium effort is, depending on parameter values, either...

  14. Endogeneously arising network allocation rules

    NARCIS (Netherlands)

    Slikker, M.

    2006-01-01

    In this paper we study endogenously arising network allocation rules. We focus on three allocation rules: the Myerson value, the position value and the component-wise egalitarian solution. For any of these three rules we provide a characterization based on component efficiency and some balanced

  15. Endogenizing Prospect Theory's Reference Point

    OpenAIRE

    Ulrich Schmidt; Horst Zank

    2010-01-01

    In previous models of (cumulative) prospect theory reference-dependence of preferences is imposed beforehand and the location of the reference point is exogenously determined. This note provides a foundation of prospect theory, where reference-dependence is derived from preference conditions and a unique reference point arises endogenously.

  16. Lipid Panel

    Science.gov (United States)

    ... A routine cardiac risk assessment typically includes a fasting lipid panel. Beyond that, research continues into the usefulness of other non-traditional markers of cardiac risk, such as Lp-PLA 2 . A health practitioner may choose to evaluate one or more ...

  17. LipidPedia: a comprehensive lipid knowledgebase.

    Science.gov (United States)

    Kuo, Tien-Chueh; Tseng, Yufeng Jane

    2018-04-10

    Lipids are divided into fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, sterols, prenol lipids and polyketides. Fatty acyls and glycerolipids are commonly used as energy storage, whereas glycerophospholipids, sphingolipids, sterols and saccharolipids are common used as components of cell membranes. Lipids in fatty acyls, glycerophospholipids, sphingolipids and sterols classes play important roles in signaling. Although more than 36 million lipids can be identified or computationally generated, no single lipid database provides comprehensive information on lipids. Furthermore, the complex systematic or common names of lipids make the discovery of related information challenging. Here, we present LipidPedia, a comprehensive lipid knowledgebase. The content of this database is derived from integrating annotation data with full-text mining of 3,923 lipids and more than 400,000 annotations of associated diseases, pathways, functions, and locations that are essential for interpreting lipid functions and mechanisms from over 1,400,000 scientific publications. Each lipid in LipidPedia also has its own entry containing a text summary curated from the most frequently cited diseases, pathways, genes, locations, functions, lipids and experimental models in the biomedical literature. LipidPedia aims to provide an overall synopsis of lipids to summarize lipid annotations and provide a detailed listing of references for understanding complex lipid functions and mechanisms. LipidPedia is available at http://lipidpedia.cmdm.tw. yjtseng@csie.ntu.edu.tw. Supplementary data are available at Bioinformatics online.

  18. Investigation of ionizing sublethal doses effects on endogenous radioresistance background

    International Nuclear Information System (INIS)

    Kudryashov, Yu.B.; Goncharenko, E.N.; Antonova, S.V.; Akhalaya, M.Ya.; Bajzhumanov, A.A.; Shestakova, S.V.

    1997-01-01

    Sublethal doses of X-radiation (0.5 Gy and 1 Gy) caused the alterations in levels of main components of endogenous radioresistance background in rat tissues. There were demonstrated the decrease of serotonin content in stomach mocosa and spleen, adrenalin, noradrenalin and corticosteroids contents in adrenal glands, nonprotein thiols content in spleen and the increase of lipid peroxide level in serum on the 3-14 days after irradiation. The recovery of the investigated parameters was occurred to the 21 day after exposure. (author)

  19. The epigenetic alterations of endogenous retroelements in aging.

    Science.gov (United States)

    Cardelli, Maurizio

    2018-02-16

    Endogenous retroelements, transposons that mobilize through RNA intermediates, include some of the most abundant repetitive sequences of the human genome, such as Alu and LINE-1 sequences, and human endogenous retroviruses. Recent discoveries demonstrate that these mobile genetic elements not only act as intragenomic parasites, but also exert regulatory roles in living cells. The risk of genomic instability represented by endogenous retroelements is normally counteracted by a series of epigenetic control mechanisms which include, among the most important, CpG DNA methylation. Indeed, most of the genomic CpG sites subjected to DNA methylation in the nuclear DNA are carried by these repetitive elements. As other parts of the genome, endogenous retroelements and other transposable elements are subjected to deep epigenetic alterations during aging, repeatedly observed in the context of organismal and cellular senescence, in human and other species. This review summarizes the current status of knowledge about the epigenetic alterations occurring in this large, non-genic portion of the genome in aging and age-related conditions, with a focus on the causes and the possible functional consequences of these alterations. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Endogenous opiates and behavior: 2014.

    Science.gov (United States)

    Bodnar, Richard J

    2016-01-01

    This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants). This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular

  1. Lipid flopping in the liver.

    Science.gov (United States)

    Linton, Kenneth J

    2015-10-01

    Bile is synthesized in the liver and is essential for the emulsification of dietary lipids and lipid-soluble vitamins. It is a complex mixture of amphiphilic bile acids (BAs; which act as detergent molecules), the membrane phospholipid phosphatidylcholine (PC), cholesterol and a variety of endogenous metabolites and waste products. Over the last 20 years, the combined effort of clinicians, geneticists, physiologists and biochemists has shown that each of these bile components is transported across the canalicular membrane of the hepatocyte by its own specific ATP-binding cassette (ABC) transporter. The bile salt export pump (BSEP) ABCB11 transports the BAs and drives bile flow from the liver, but it is now clear that two lipid transporters, ABCB4 (which flops PC into the bile) and the P-type ATPase ATP8B1/CDC50 (which flips a different phospholipid in the opposite direction) play equally critical roles that protect the biliary tree from the detergent activity of the bile acids. Understanding the interdependency of these lipid floppases and flippases has allowed the development of an assay to measure ABCB4 function. ABCB4 harbours numerous mis-sense mutations which probably reflects the spectrum of liver disease rooted in ABCB4 aetiology. Characterization of the effect of these mutations at the protein level opens the possibility for the development of personalized prognosis and treatment. © 2015 Authors; published by Portland Press Limited.

  2. Endogenous scheduling preferences and congestion

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Small, Kenneth

    2017-01-01

    We consider the timing of activities through a dynamic model of commuting with congestion, in which workers care solely about leisure and consumption. Implicit preferences for the timing of the commute form endogenously due to temporal agglomeration economies. Equilibrium exists uniquely and is i......We consider the timing of activities through a dynamic model of commuting with congestion, in which workers care solely about leisure and consumption. Implicit preferences for the timing of the commute form endogenously due to temporal agglomeration economies. Equilibrium exists uniquely...... and is indistinguishable from that of a generalized version of the classical Vickrey bottleneck model, based on exogenous trip-timing preferences, but optimal policies differ: the Vickrey model will misstate the benefits of a capacity increase, it will underpredict the benefits of congestion pricing, and pricing may make...

  3. Exogenic and endogenic Europa minerals

    Science.gov (United States)

    Maynard-Casely, H. E.; Brand, H. E. A.; Wilson, S. A.

    2016-12-01

    The Galileo Near Infrared Mapping Spectrometer (NIMS) identified a significant `non-ice' component upon the surface of Jupiter's moon Europa. Current explanations invoke both endogenic and exogenic origins for this material. It has long been suggested that magnesium and sodium sulfate minerals could have leached from the rock below a putative ocean (endogenic) 1 and that sulfuric acid hydrate minerals could have been radiologically produced from ionised sulfur originally from Io's volcanoes (exogenic) 2. However, a more recent theory proposes that the `non-ice' component could be radiation damaged NaCl leached from Europa's speculative ocean 3. What if the minerals are actually from combination of both endogenic and exogenic sources? To investigate this possibility we have focused on discovering new minerals that might form in the combination of the latter two cases, that is a mixture of leached sulfates hydrates with radiologically produced sulfuric acid. To this end we have explored a number of solutions in the MgSO4-H2SO4-H2O and Na2SO4-H2SO4-H2O systems, between 80 and 280 K with synchrotron x-ray powder diffraction. We report a number of new materials formed in this these ternary systems. This suggests that it should be considered that the `non-ice' component of the Europa's surface could be a material derived from endogenic and exogenic components. 1 Kargel, J. S. Brine volcanism and the interior structures of asteroids and icy satellites. Icarus 94, 368-390 (1991). 2 Carlson, R. W., Anderson, M. S., Mehlman, R. & Johnson, R. E. Distribution of hydrate on Europa: Further evidence for sulfuric acid hydrate. Icarus 177, 461-471, doi:10.1016/j.icarus.2005.03.026 (2005). 3 Hand, K. P. & Carlson, R. W. Europa's surface color suggests an ocean rich with sodium chloride. Geophysical Research Letters, 2015GL063559, doi:10.1002/2015gl063559 (2015).

  4. Money, banks and endogenous volatility

    OpenAIRE

    Pere Gomis-Porqueras

    2000-01-01

    In this paper I consider a monetary growth model in which banks provide liquidity, and the government fixes a constant rate of money creation. There are two underlying assets in the economy, money and capital. Money is dominated in rate of return. In contrast to other papers with a larger set of government liabilities, I find a unique equilibrium when agents' risk aversion is moderate. However, indeterminacies and endogenous volatility can be observed when agents are relatively risk averse.

  5. OXYGEN ABUNDANCES IN CEPHEIDS

    International Nuclear Information System (INIS)

    Luck, R. E.; Andrievsky, S. M.; Korotin, S. N.; Kovtyukh, V. V.

    2013-01-01

    Oxygen abundances in later-type stars, and intermediate-mass stars in particular, are usually determined from the [O I] line at 630.0 nm, and to a lesser extent, from the O I triplet at 615.7 nm. The near-IR triplets at 777.4 nm and 844.6 nm are strong in these stars and generally do not suffer from severe blending with other species. However, these latter two triplets suffer from strong non-local thermodynamic equilibrium (NLTE) effects and thus see limited use in abundance analyses. In this paper, we derive oxygen abundances in a large sample of Cepheids using the near-IR triplets from an NLTE analysis, and compare those abundances to values derived from a local thermodynamic equilibrium (LTE) analysis of the [O I] 630.0 nm line and the O I 615.7 nm triplet as well as LTE abundances for the 777.4 nm triplet. All of these lines suffer from line strength problems making them sensitive to either measurement complications (weak lines) or to line saturation difficulties (strong lines). Upon this realization, the LTE results for the [O I] lines and the O I 615.7 nm triplet are in adequate agreement with the abundance from the NLTE analysis of the near-IR triplets.

  6. Analysis of Lipid Experiments (ALEX)

    DEFF Research Database (Denmark)

    Husen, Peter; Tarasov, Kirill; Katafiasz, Maciej

    2013-01-01

    Global lipidomics analysis across large sample sizes produces high-content datasets that require dedicated software tools supporting lipid identification and quantification, efficient data management and lipidome visualization. Here we present a novel software-based platform for streamlined data...... processing, management and visualization of shotgun lipidomics data acquired using high-resolution Orbitrap mass spectrometry. The platform features the ALEX framework designed for automated identification and export of lipid species intensity directly from proprietary mass spectral data files......, and an auxiliary workflow using database exploration tools for integration of sample information, computation of lipid abundance and lipidome visualization. A key feature of the platform is the organization of lipidomics data in "database table format" which provides the user with an unsurpassed flexibility...

  7. REFERENCE MODELS OF ENDOGENOUS ECONOMIC GROWTH

    OpenAIRE

    GEAMĂNU MARINELA

    2012-01-01

    The new endogenous growth theories are a very important research area for shaping the most effective policies and long term sustainable development strategies. Endogenous growth theory has emerged as a reaction to the imperfections of neoclassical theory, by the fact that the economic growth is the endogenous product of an economical system.

  8. Discovery and Characterization of an Endogenous CXCR4 Antagonist

    Directory of Open Access Journals (Sweden)

    Onofrio Zirafi

    2015-05-01

    Full Text Available CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhibitors of CXCR4-tropic HIV-1 strains. This approach identified a 16 amino acid fragment of serum albumin as an effective and highly specific CXCR4 antagonist. The endogenous peptide, termed EPI-X4, is evolutionarily conserved and generated from the highly abundant albumin precursor by pH-regulated proteases. EPI-X4 forms an unusual lasso-like structure and antagonizes CXCL12-induced tumor cell migration, mobilizes stem cells, and suppresses inflammatory responses in mice. Furthermore, the peptide is abundant in the urine of patients with inflammatory kidney diseases and may serve as a biomarker. Our results identify EPI-X4 as a key regulator of CXCR4 signaling and introduce proteolysis of an abundant precursor protein as an alternative concept for chemokine receptor regulation.

  9. Altered cellular redox status, sirtuin abundance and clock gene expression in a mouse model of developmentally primed NASH.

    Science.gov (United States)

    Bruce, Kimberley D; Szczepankiewicz, Dawid; Sihota, Kiran K; Ravindraanandan, Manoj; Thomas, Hugh; Lillycrop, Karen A; Burdge, Graham C; Hanson, Mark A; Byrne, Christopher D; Cagampang, Felino R

    2016-07-01

    We have previously shown that high fat (HF) feeding during pregnancy primes the development of non-alcoholic steatohepatits (NASH) in the adult offspring. However, the underlying mechanisms are unclear. Since the endogenous molecular clock can regulate hepatic lipid metabolism, we investigated whether exposure to a HF diet during development could alter hepatic clock gene expression and contribute to NASH onset in later life. Female mice were fed either a control (C, 7%kcal fat) or HF (45%kcal fat) diet. Offspring were fed either a C or HF diet resulting in four offspring groups: C/C, C/HF, HF/C and HF/HF. NAFLD progression, cellular redox status, sirtuin expression (Sirt1, Sirt3), and the expression of core clock genes (Clock, Bmal1, Per2, Cry2) and clock-controlled genes involved in lipid metabolism (Rev-Erbα, Rev-Erbβ, RORα, and Srebp1c) were measured in offspring livers. Offspring fed a HF diet developed NAFLD. However HF fed offspring of mothers fed a HF diet developed NASH, coupled with significantly reduced NAD(+)/NADH (pNASH in adulthood, involving altered cellular redox status, reduced sirtuin abundance, and desynchronized clock gene expression. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  10. On the origins of endogenous thoughts.

    Science.gov (United States)

    Tillas, Alexandros

    2017-05-01

    Endogenous thoughts are thoughts that we activate in a top-down manner or in the absence of the appropriate stimuli. We use endogenous thoughts to plan or recall past events. In this sense, endogenous thinking is one of the hallmarks of our cognitive lives. In this paper, I investigate how it is that we come to possess endogenous control over our thoughts. Starting from the close relation between language and thinking, I look into speech production-a process motorically controlled by the inferior frontal gyrus (IFG). Interestingly, IFG is also closely related to silent talking, as well as volition. The connection between IFG and volition is important given that endogenous thoughts are or at least greatly resemble voluntary actions. Against this background, I argue that IFG is key to understanding the origins of conscious endogenous thoughts. Furthermore, I look into goal-directed thinking and show that IFG plays a key role also in unconscious endogenous thinking.

  11. Orion A helium abundance

    International Nuclear Information System (INIS)

    Tsivilev, A.P.; Ershov, A.A.; Smirnov, G.T.; Sorochenko, R.L.

    1986-01-01

    The 22.4-GHz (H,He)66-alpha and 36.5-GHz (H,He)56-alpha radio recombination lines have been observed at several Jaffe-Pankonin positions in the central part of the Orion A source. The measured relative abundance of ionized helium increases with distance, averaging 11.6 percent at peripheral points. The observed behavior is interpreted by a blister-type model nebula, which implies that Orion A has a true He abundance of 12 percent, is moving with a radial velocity of 5 km/sec, and is expanding. 18 references

  12. Pathophysiological Features of Endogenous Intoxication in Pregnant Women with Arterial Hypertension

    Directory of Open Access Journals (Sweden)

    N. V. Kabanova

    2008-01-01

    Full Text Available Objective: to determine the nature and specific features of development of endogenous intoxication in pregnant women with arterial hypertension. Subjects and materials. Humoral extracellular fluid volume regulation, partial renal functions, placental hormonal function, membranous lipid peroxidation activity, antiradical defense, the parameters of central hemodynamics, endogenous intoxication, and a biochemical coagulogram were studied and differential blood count with the leukocytic ratio indices was estimated in 172 pregnant females with arterial hypertension and 54 healthy pregnant ones in the third trimester. The statistical package «Stadia» was applied. Results. Arterial hypertension caused by pregnancy was ascertained to involve pathogenetically different types: low-, normal-, and high-renin ones. In pregnant women with arterial hypertension, the general pathogenetic homeostatic changes were placental hormonal imbalance, activated membranous lipid peroxidation, impaired lymph outflow, sodium and water retention, hepatic and renal failure, and endogenous intoxication. Conclusion. Placental ischemia appearing as placental hormonal imbalance (extrarenal pressor system was accompanied by a compensatory humoral response: arterial hypertension and metabolic disturbances. Changes in medium-weight molecule 280, leukocytic intoxication index, erythrocytic sorption capacity, and Paramecium test, by confirming the presence of endogenous intoxication in pregnant females with arterial hypertension, were caused by a type of arterial hypertension (by the hemodynamic profile and the type of impaired partial renal functions. Key words: pregnancy, arterial hypertension, endogenous intoxication.

  13. Endogenous scheduling preferences and congestion

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Small, Kenneth

    2010-01-01

    and leisure, but agglomeration economies at home and at work lead to scheduling preferences forming endogenously. Using bottleneck congestion technology, we obtain an equilibrium queuing pattern consistent with a general version of the Vickrey bottleneck model. However, the policy implications are different....... Compared to the predictions of an analyst observing untolled equilibrium and taking scheduling preferences as exogenous, we find that both the optimal capacity and the marginal external cost of congestion have changed. The benefits of tolling are greater, and the optimal time varying toll is different....

  14. Endogenous money, circuits and financialization

    OpenAIRE

    Malcolm Sawyer

    2013-01-01

    This paper locates the endogenous money approach in a circuitist framework. It argues for the significance of the credit creation process for the evolution of the economy and the absence of any notion of ‘neutrality of money’. Clearing banks are distinguished from other financial institutions as the providers of initial finance in a circuit whereas other financial institutions operate in a final finance circuit. Financialization is here viewed in terms of the growth of financial assets an...

  15. Stellar Oxygen Abundances

    Science.gov (United States)

    King, Jeremy

    1994-04-01

    This dissertation addresses several issues concerning stellar oxygen abundances. The 7774 {\\AA} O I triplet equivalent widths of Abia & Rebolo [1989, AJ, 347, 186] for metal-poor dwarfs are found to be systematically too high. I also argue that current effective temperatures used in halo star abundance studies may be ~150 K too low. New color-Teff relations are derived for metal-poor stars. Using the revised Teff values and improved equivalent widths for the 7774A O I triplet, the mean [O/Fe] ratio for a handful of halo stars is found to be +0.52 with no dependence on Teff or [Fe/H]. Possible cosmological implications of the hotter Teff scale are discussed along with additional evidence supporting the need for a higher temperature scale for metal-poor stars. Our Teff scale leads to a Spite Li plateau value of N(Li)=2.28 +/- 0.09. A conservative minimal primordial value of N(Li)=2.35 is inferred. If errors in the observations and models are considered, consistency with standard models of Big Bang nucleosynthesis is still achieved with this larger Li abundance. The revised Teff scale raises the observed B/Be ratio of HD 140283 from 10 to 12, making its value more comfortably consistent with the production of the observed B and Be by ordinary spallation. Our Teff values are found to be in good agreement with values predicted from both the Victoria and Yale isochrone color-Teff relations. Thus, it appears likely that no changes in globular cluster ages would result. Next, we examine the location of the break in the [O/Fe] versus [Fe/H] plane in a quantitative fashion. Analysis of a relatively homogeneous data set does not favor any unique break point in the range -1.7 /= -3), in agreement with the new results for halo dwarfs. We find that the gap in the observed [O/H] distribution, noted by Wheeler et al. [1989, ARAA, 27, 279], persists despite the addition of more O data and may betray the occurrence of a hiatus in star formation between the end of halo formation and

  16. Determination of endogenous nitrogen in feces using 15N tracers

    International Nuclear Information System (INIS)

    Herrmann, U.; Krawielitzki, K.; Schadereit, R.; Smulikowska, S.

    1986-01-01

    A ration consisting of wheat gluten and N-free components was supplemented with L-lysine and L-leucine and fed to two groups of growing Wistar rats. Group 1 received 15 N Lys and unlabelled Leu, group 2 received unlabelled Lys and 15 N Leu in order to study the influence of the utilization of the 15 N marker on the labelling quota of feces and urine as well as various fractions of the body. The good utilization of Lys in group 1 results in a higher 15 N excess in feces and a reduced 15 N abundance in urine in comparison to group 2 with a lower utilization of 15 N Leu. The results show that the 15 N abundance in urine is unsuitable as an indicator of the 15 N labelling quota of endogenous metabolic fecal nitrogen. (author)

  17. Human-Specific Endogenous Retroviruses

    Directory of Open Access Journals (Sweden)

    Anton Buzdin

    2007-01-01

    Full Text Available This review focuses on a small family of human-specific genomic repetitive elements, presented by 134 members that shaped ~330 kb of the human DNA. Although modest in terms of its copy number, this group appeared to modify the human genome activity by endogenizing ~50 functional copies of viral genes that may have important implications in the immune response, cancer progression, and antiretroviral host defense. A total of 134 potential promoters and enhancers have been added to the human DNA, about 50% of them in the close gene vicinity and 22% in gene introns. For 60 such human-specific promoters, their activity was confirmed by in vivo assays, with the transcriptional level varying ~1000-fold from hardly detectable to as high as ~3% of β-actin transcript level. New polyadenylation signals have been provided to four human RNAs, and a number of potential antisense regulators of known human genes appeared due to human-specific retroviral insertional activity. This information is given here in the context of other major genomic changes underlining differences between human and chimpanzee DNAs. Finally, a comprehensive database, is available for download, of human-specific and polymorphic endogenous retroviruses is presented, which encompasses the data on their genomic localization, primary structure, encoded viral genes, human gene neighborhood, transcriptional activity, and methylation status.

  18. Endogenous Opiates and Behavior: 2006

    Science.gov (United States)

    Bodnar, Richard J.

    2009-01-01

    This paper is the twenty-ninth consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning thirty years of research. It summarizes papers published during 2006 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurological disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17). PMID:17949854

  19. Endogenous opiates and behavior: 2012.

    Science.gov (United States)

    Bodnar, Richard J

    2013-12-01

    This paper is the thirty-fifth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2012 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17). Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Pex35 is a regulator of peroxisome abundance

    DEFF Research Database (Denmark)

    Yofe, Ido; Soliman, Kareem; Chuartzman, Silvia G

    2017-01-01

    Peroxisomes are cellular organelles with vital functions in lipid, amino acid, and redox metabolism. The cellular formation and dynamics of peroxisomes are governed by PEX genes, however, the regulation of peroxisome abundance is yet poorly understood. Here we use a high-content microscopy screen...

  1. Endogenous money: the evolutionary versus revolutionary views

    OpenAIRE

    Louis-Philippe Rochon; Sergio Rossi

    2013-01-01

    The purpose of this paper is to shed light on the endogenous nature of money. Contrary to the established post-Keynesian, or evolutionary, view, this paper argues that money has always been endogenous, irrespective of the historical period. Instead of the evolutionary theory of money and banking that can be traced back to Chick (1986), this paper puts forward a revolutionary definition of endogenous money consistent with many aspects of post-Keynesian economics as well as with the monetary ci...

  2. Endogenous price flexibility and optimal monetary policy

    OpenAIRE

    Ozge Senay; Alan Sutherland

    2014-01-01

    Much of the literature on optimal monetary policy uses models in which the degree of nominal price flexibility is exogenous. There are, however, good reasons to suppose that the degree of price flexibility adjusts endogenously to changes in monetary conditions. This article extends the standard new Keynesian model to incorporate an endogenous degree of price flexibility. The model shows that endogenizing the degree of price flexibility tends to shift optimal monetary policy towards complete i...

  3. Apolipoprotein gene involved in lipid metabolism

    Science.gov (United States)

    Rubin, Edward; Pennacchio, Len A.

    2007-07-03

    Methods and materials for studying the effects of a newly identified human gene, APOAV, and the corresponding mouse gene apoAV. The sequences of the genes are given, and transgenic animals which either contain the gene or have the endogenous gene knocked out are described. In addition, single nucleotide polymorphisms (SNPs) in the gene are described and characterized. It is demonstrated that certain SNPs are associated with diseases involving lipids and triglycerides and other metabolic diseases. These SNPs may be used alone or with SNPs from other genes to study individual risk factors. Methods for intervention in lipid diseases, including the screening of drugs to treat lipid-related or diabetic diseases are also disclosed.

  4. Ammonia abundances in comets

    Science.gov (United States)

    Wyckoff, S.; Tegler, S.; Engel, L.

    The emission band strengths of the NH2 bands of Comets Halley, Hartley-Good, Thiele, and Borrelly were measured to determine the NH2 column densities for the comets. Production rates obtained using the Haser and vectorial models are in agreement within the observational errors, suggesting that a simple two-step decay model may be used to approximate the NH2 distribution in a comet's coma. Ammonia-to-water abundance ratios from 0.01 to 0.4 percent were found for the four comets. The ratio in Comet Halley is found to be Q(NH3)/Q(H2O) = 0.002 + or - 0.001. No significant difference in the ammonia abundance was found before or after perihelion in Comet Halley.

  5. Compilation of solar abundance data

    International Nuclear Information System (INIS)

    Hauge, Oe.; Engvold, O.

    1977-01-01

    Interest in the previous compilations of solar abundance data by the same authors (ITA--31 and ITA--39) has led to this third, revised edition. Solar abundance data of 67 elements are tabulated and in addition upper limits for the abundances of 5 elements are listed. References are made to 167 papers. A recommended abundance value is given for each element. (JIW)

  6. Endogenous, Imperfectly Competitive Business Cycles

    DEFF Research Database (Denmark)

    Whitta-Jacobsen, Hans Jørgen

    We investigate how imperfect competition affects the occurrence and the properties of endogenous, rational expectations business cycles in an overlapping generations model with constant returns to scale in production. The model has explicit product and labor markets all characterized...... by monopolistic competition. An implicit assumption of barriers to entry justifies that the number of firms is fixed even when positive profits occur. It turns out that both market power of firms on the product markets and market power of unions on the labor markets make the occurrence of cycles more likely....... In particular, imperfect competition on the product markets and the positive profits associated with it may have the effect that there is a cycle even if the labor supply curve is increasing in the real-wage rate. For competitive cycles is required not only a decreasing labor supply curve, but a wage elasticity...

  7. Abundances in galaxies

    International Nuclear Information System (INIS)

    Pagel, B.E.J.

    1991-01-01

    Standard (or mildly inhomogeneous) Big Bang nucleosynthesis theory is well confirmed by abundance measurements of light elements up to 7 Li and the resulting upper limit to the number of neutrino families confirmed in accelerator experiments. Extreme inhomogeneous models with a closure density in form of baryons seem to be ruled out and there is no evidence for a cosmic 'floor' to 9 Be or heavier elements predicted in some versions of those models. Galaxies show a correlation between luminous mass and abundance of carbon and heavier elements, usually attributed to escape of hot gas from shallow potential wells. Uncertainties include the role of dark matter and biparametric behaviour of ellipticals. Spirals have radial gradients which may arise from a variety of causes. In our own Galaxy one can distinguish three stellar populations - disk, halo and bulge - characterised by differing metallicity distribution functions. Differential abundance effects are found among different elements in stars as a function of metallicity and presumably age, notably in the ratio of oxygen and α-particle elements to iron. These may eventually be exploitable to set a time scale for the formation of the halo, bulge and disk. (orig.)

  8. Correlation between anthropometric measurement, lipid profile, dietary vitamins, serum antioxidants, lipoprotein (a and lipid peroxides in known cases of 345 elderly hypertensive South Asian aged 56–64 y–A hospital based study

    Directory of Open Access Journals (Sweden)

    Arun Kumar

    2014-05-01

    Conclusions: Based on the observations, our study concludes that hypertension is caused due to interplay of several confounding factors namely anthropometry, lipid profile, depletion of endogenous antioxidants and rise in oxidative stress.

  9. Involvement of human endogenous retroviral syncytin-1 in human osteoclast fusion

    DEFF Research Database (Denmark)

    Søe, Kent; Andersen, Thomas Lykke; Hobolt-Pedersen, Anne-Sofie

    2011-01-01

    fusion of the lipid bilayers of their cell membranes are still unknown. Syncytin-1 is a protein encoded by a human endogenous retroviral gene which was stably integrated into the human ancestor genome more than 24 million years ago. Upon activation, syncytin-1 is able to destabilize the lipid bilayer....... This was documented through Q-PCR, Western blot and immunofluorescence analyses. These in vitro findings were confirmed by immunohistochemical stainings in human iliac crest biopsies. A syncytin-1 inhibitory peptide reduced the number of nuclei per osteoclast by 30%, as well as TRACP activity. From a mechanistic...

  10. Chemical Atherogenesis: Role of Endogenous and Exogenous Poisons in Disease Development

    Directory of Open Access Journals (Sweden)

    Matthew K. Ross

    2014-01-01

    Full Text Available Chemical atherogenesis is an emerging field that describes how environmental pollutants and endogenous toxins perturb critical pathways that regulate lipid metabolism and inflammation, thus injuring cells found within the vessel wall. Despite growing awareness of the role of environmental pollutants in the development of cardiovascular disease, the field of chemical atherogenesis can broadly include both exogenous and endogenous poisons and the study of molecular, biochemical, and cellular pathways that become dysregulated during atherosclerosis. This integrated approach is logical because exogenous and endogenous toxins often share the same mechanism of toxicity. Chemical atherogenesis is a truly integrative discipline because it incorporates concepts from several different fields, including biochemistry, chemical biology, pharmacology, and toxicology. This review will provide an overview of this emerging research area, focusing on cellular and animal models of disease.

  11. Chemical Atherogenesis: Role of Endogenous and Exogenous Poisons in Disease Development.

    Science.gov (United States)

    Ross, Matthew K; Matthews, Anberitha T; Mangum, Lee C

    Chemical atherogenesis is an emerging field that describes how environmental pollutants and endogenous toxins perturb critical pathways that regulate lipid metabolism and inflammation, thus injuring cells found within the vessel wall. Despite growing awareness of the role of environmental pollutants in the development of cardiovascular disease, the field of chemical atherogenesis can broadly include both exogenous and endogenous poisons and the study of molecular, biochemical, and cellular pathways that become dysregulated during atherosclerosis. This integrated approach is logical because exogenous and endogenous toxins often share the same mechanism of toxicity. Chemical atherogenesis is a truly integrative discipline because it incorporates concepts from several different fields, including biochemistry, chemical biology, pharmacology, and toxicology. This review will provide an overview of this emerging research area, focusing on cellular and animal models of disease.

  12. Applying Endogenous Knowledge in the African Context ...

    African Journals Online (AJOL)

    The question presented in this article is how to improve the dispute resolution competence of practitioners in Africa. The response offered involves enhancing the endogenous knowledge of a dispute and how to resolve it. This requires not only an understanding of what endogenous knowledge is, but also an alignment of ...

  13. Endogenous Peer Effects: Fact or Fiction?

    Science.gov (United States)

    Yeung, Ryan; Nguyen-Hoang, Phuong

    2016-01-01

    The authors examine endogenous peer effects, which occur when a student's behavior or outcome is a function of the behavior or outcome of his or her peer group. Endogenous peer effects have important implications for educational policies such as busing, school choice and tracking. In this study, the authors quantitatively review the literature on…

  14. Spontaneous charged lipid transfer between lipid vesicles.

    Science.gov (United States)

    Richens, Joanna L; Tyler, Arwen I I; Barriga, Hanna M G; Bramble, Jonathan P; Law, Robert V; Brooks, Nicholas J; Seddon, John M; Ces, Oscar; O'Shea, Paul

    2017-10-03

    An assay to study the spontaneous charged lipid transfer between lipid vesicles is described. A donor/acceptor vesicle system is employed, where neutrally charged acceptor vesicles are fluorescently labelled with the electrostatic membrane probe Fluoresceinphosphatidylethanolamine (FPE). Upon addition of charged donor vesicles, transfer of negatively charged lipid occurs, resulting in a fluorescently detectable change in the membrane potential of the acceptor vesicles. Using this approach we have studied the transfer properties of a range of lipids, varying both the headgroup and the chain length. At the low vesicle concentrations chosen, the transfer follows a first-order process where lipid monomers are transferred presumably through the aqueous solution phase from donor to acceptor vesicle. The rate of transfer decreases with increasing chain length which is consistent with energy models previously reported for lipid monomer vesicle interactions. Our assay improves on existing methods allowing the study of a range of unmodified lipids, continuous monitoring of transfer and simplified experimental procedures.

  15. Endogenous α-crystallin inhibits expression of caspase-3 induced by hypoxia in retinal neurons.

    Science.gov (United States)

    Ying, Xi; Peng, Yanli; Zhang, Jiaping; Wang, Xingli; Wu, Nan; Zeng, Yuxiao; Wang, Yi

    2014-08-28

    To investigate the expression of endogenous, hypoxic stress-induced α-crystallin and caspase-3 in rat retinal neurons in vitro. Retinal neurons were cultured from Long-Evans rats. The expression of endogenous α-crystallin was analyzed by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). Furthermore, hypoxic exposure was performed in cultured cells, and the expression of endogenous α-crystallin and caspase-3 was assayed by Western blotting. Positive α-crystallin staining was observed in cultured retinal neurons, and expression of endogenous α-crystallin mRNA peaked 3-5d after inoculation (Pendogenous, hypoxic stress-induced α-crystallin expression increased gradually, peaking 6h after hypoxia. The expression was more abundant compared to the control (Pendogenous α-crystallin in retinal neurons, especially over-expression induced by hypoxic stress, results in the down regulation of caspase-3. The data suggest that endogenous α-crystallin may act as an endogenous neuroprotective factor in retinal neurons. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Anomalous behavior of tellurium abundances

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B L

    1984-01-01

    The cosmic abundance of Te is larger than for any element with atomic number greater than 40, but it is one of the least abundant elements in the earth's lithosphere and it is one of the five elements never reported in sea water. On the other hand, it is the fourth most abundant element in the human body (after Fe, Zn and Rb), and is unusually abundant in human food. It is shown that the high abundance in human food combined with the low abundance in soil requires that it be picked up by plant roots very much more efficiently than any other trace element.

  17. Human endogenous retroviruses and ADHD.

    Science.gov (United States)

    Balestrieri, Emanuela; Pitzianti, Mariabernarda; Matteucci, Claudia; D'Agati, Elisa; Sorrentino, Roberta; Baratta, Antonia; Caterina, Rosa; Zenobi, Rossella; Curatolo, Paolo; Garaci, Enrico; Sinibaldi-Vallebona, Paola; Pasini, Augusto

    2014-08-01

    Several lines of evidences suggest that human endogenous retroviruses (HERVs) are implicated in the development of many complex diseases with a multifactorial aetiology and a strong heritability, such as neurological and psychiatric diseases. Attention deficit hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that results from a complex interaction of environmental, biological and genetic factors. Our aim was to analyse the expression levels of three HERV families (HERV-H, K and W) in patients with ADHD. The expression of retroviral mRNAs from the three HERV families was evaluated in peripheral blood mononuclear cells (PBMCs) from 30 patients with ADHD and 30 healthy controls by quantitative RT-PCR. The expression levels of HERV-H are significantly higher in patients with ADHD compared to healthy controls, while there are no differences in the expression levels of HERV-K and W. Since the ADHD aetiology is due to a complex interaction of environmental, biological and genetic factors, HERVs may represent one link among these factors and clinical phenotype of ADHD. A future confirmation of HERV-H overexpression in a larger number of ADHD patients will make possible to identify it as a new parameter for this clinical condition, also contributing to deepen the study on the role of HERVs in the neurodevelopment diseases.

  18. Abundance, Excess, Waste

    Directory of Open Access Journals (Sweden)

    Rox De Luca

    2016-02-01

    Her recent work focuses on the concepts of abundance, excess and waste. These concerns translate directly into vibrant and colourful garlands that she constructs from discarded plastics collected on Bondi Beach where she lives. The process of collecting is fastidious, as is the process of sorting and grading the plastics by colour and size. This initial gathering and sorting process is followed by threading the components onto strings of wire. When completed, these assemblages stand in stark contrast to the ease of disposability associated with the materials that arrive on the shoreline as evidence of our collective human neglect and destruction of the environment around us. The contrast is heightened by the fact that the constructed garlands embody the paradoxical beauty of our plastic waste byproducts, while also evoking the ways by which those byproducts similarly accumulate in randomly assorted patterns across the oceans and beaches of the planet.

  19. Gravity effects on endogenous movements

    Science.gov (United States)

    Johnsson, Anders; Antonsen, Frank

    Gravity effects on endogenous movements A. Johnsson * and F. Antonsen *+ * Department of Physics, Norwegian University of Science and Technology,NO-7491, Trond-heim, Norway, E-mail: anders.johnsson@ntnu.no + Present address: Statoil Research Center Trondheim, NO-7005, Trondheim, Norway Circumnutations in stems/shoots exist in many plants and often consists of more or less regular helical movements around the plumb line under Earth conditions. Recent results on circumnu-tations of Arabidopsis in space (Johnsson et al. 2009) showed that minute amplitude oscilla-tions exist in weightlessness, but that centripetal acceleration (mimicking the gravity) amplified and/or created large amplitude oscillations. Fundamental mechanisms underlying these results will be discussed by modeling the plant tissue as a cylinder of cells coupled together. As a starting point we have modeled (Antonsen 1998) standing waves on a ring of biological cells, as first discussed in a classical paper (Turing 1952). If the coupled cells can change their water content, an `extension' wave could move around the ring. We have studied several, stacked rings of cells coupled into a cylinder that together represent a cylindrical plant tissue. Waves of extensions travelling around the cylinder could then represent the observable circumnutations. The coupling between cells can be due to cell-to-cell diffusion, or to transport via channels, and the coupling can be modeled to vary in both longitudinal and transversal direction of the cylinder. The results from ISS experiments indicate that this cylindrical model of coupled cells should be able to 1) show self-sustained oscillations without the impact of gravity (being en-dogenous) and 2) show how an environmental factor like gravity can amplify or generate the oscillatory movements. Gravity has been introduced in the model by a negative, time-delayed feed-back transport across the cylinder. This represents the physiological reactions to acceler

  20. Transcriptional Regulation of T-Cell Lipid Metabolism: Implications for Plasma Membrane Lipid Rafts and T-Cell Function

    Directory of Open Access Journals (Sweden)

    George A. Robinson

    2017-11-01

    Full Text Available It is well established that cholesterol and glycosphingolipids are enriched in the plasma membrane (PM and form signaling platforms called lipid rafts, essential for T-cell activation and function. Moreover, changes in PM lipid composition affect the biophysical properties of lipid rafts and have a role in defining functional T-cell phenotypes. Here, we review the role of transcriptional regulators of lipid metabolism including liver X receptors α/β, peroxisome proliferator-activated receptor γ, estrogen receptors α/β (ERα/β, and sterol regulatory element-binding proteins in T-cells. These receptors lie at the interface between lipid metabolism and immune cell function and are endogenously activated by lipids and/or hormones. Importantly, they regulate cellular cholesterol, fatty acid, glycosphingolipid, and phospholipid levels but are also known to modulate a broad spectrum of immune responses. The current evidence supporting a role for lipid metabolism pathways in controlling immune cell activation by influencing PM lipid raft composition in health and disease, and the potential for targeting lipid biosynthesis pathways to control unwanted T-cell activation in autoimmunity is reviewed.

  1. Lipidomic and proteomic analysis of Caenorhabditis elegans lipid droplets and identification of ACS-4 as a lipid droplet-associated protein

    Energy Technology Data Exchange (ETDEWEB)

    Vrablik, Tracy L. [Washington State Univ., Pullman, WA (United States); Petyuk, Vladislav A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Larson, Emily M. [Washington State Univ., Pullman, WA (United States); Smith, Richard D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Watts, Jennifer [Washington State Univ., Pullman, WA (United States)

    2015-06-27

    Lipid droplets are cytoplasmic organelles that store neutral lipids for membrane synthesis and energy reserves. In this study, we characterized the lipid and protein composition of purified C. elegans lipid droplets. These lipid droplets are composed mainly of triacylglycerols, surrounded by a phospholipid monolayer composed primarily of phosphatidylcholine and phosphatidylethanolamine. The fatty acid composition of the triacylglycerols was rich in fatty acid species obtained from the dietary E. coli, including cyclopropane fatty acids and cis-vaccenic acid. Unlike other organisms, C. elegans lipid droplets contain very little cholesterol or cholesterol esters. Comparison of the lipid droplet proteomes of wild type and high-fat daf-2 mutant strains shows a relative decrease of MDT-28 abundance in lipid droplets isolated from daf-2 mutants. Functional analysis of lipid droplet proteins identified in our proteomic studies indicated an enrichment of proteins required for growth and fat homeostasis in C. elegans.

  2. Contagion risk in endogenous financial networks

    International Nuclear Information System (INIS)

    Li, Shouwei; Sui, Xin

    2016-01-01

    Highlights: • We propose an endogenous financial network model. • Endogenous networks include interbank networks, inter-firm networks and bank-firm networks. • We investigate contagion risk in endogenous financial networks. - Abstract: In this paper, we investigate contagion risk in an endogenous financial network, which is characterized by credit relationships connecting downstream and upstream firms, interbank credit relationships and credit relationships connecting firms and banks. The findings suggest that: increasing the number of potential lenders randomly selected can lead to an increase in the number of bank bankruptcies, while the number of firm bankruptcies presents a trend of increase after the decrease; after the intensity of choice parameter rises beyond a threshold, the number of bankruptcies in three sectors (downstream firms, upstream firms and banks) shows a relatively large margin of increase, and keeps at a relatively high level; there exists different trends for bankruptcies in different sectors with the change of the parameter of credits’ interest rates.

  3. Endogenous Money, Output and Prices in India

    OpenAIRE

    Das, Rituparna

    2009-01-01

    This paper proposes to quantify the macroeconometric relationships among the variables broad money, lending by banks, price, and output in India using simultaneous equations system keeping in view the issue of endogeneity.

  4. Twilight of Abundance

    Science.gov (United States)

    Archibald, David

    2014-03-01

    Baby boomers enjoyed the most benign period in human history: fifty years of relative peace, cheap energy, plentiful grain supply, and a warming climate due to the highest solar activity for 8,000 years. The party is over - prepare for the twilight of abundance. David Archibald reveals the grim future the world faces on its current trajectory: massive fuel shortages, the bloodiest warfare in human history, a global starvation crisis, and a rapidly cooling planet. Archibald combines pioneering science with keen economic knowledge to predict the global disasters that could destroy civilization as we know it - disasters that are waiting just around the corner. But there's good news, too: We can have a good future if we prepare for it. Advanced, civilized countries can have a permanently high standard of living if they choose to invest in the technologies that will get them there. Archibald, a climate scientist as well as an inventor and a financial specialist, explains which scientific breakthroughs can save civilization in the coming crisis - if we can cut through the special interest opposition to these innovations and allow free markets to flourish.

  5. Some observations about the endogenous money theory

    OpenAIRE

    Bertocco Giancarlo

    2006-01-01

    The endogenous money theory constitutes the core element of the post-keynesian monetary theory. The first formulation of this theory can be found in the works of Kaldor published in the 1970s. Taking these studies as a starting point, the post-keynesians elaborated two versions of the endogenous money theory which differ in their assumptions about the behaviour of the monetary authorities and the banking system, and hence offer different conclusions about the slope of the money supply curve. ...

  6. Invasive fungal infections in endogenous Cushing's syndrome

    Science.gov (United States)

    Scheffel, Rafael Selbach; Dora, José Miguel; Weinert, Letícia Schwerz; Aquino, Valério; Maia, Ana Luiza; Canani, Luis Henrique; Goldani, Luciano Z.

    2010-01-01

    Cushing's syndrome is a condition characterized by elevated cortisol levels that can result from either augmented endogenous production or exogenous administration of corticosteroids. The predisposition to fungal infections among patients with hypercortisolemia has been noted since Cushing's original description of the disease. We describe here a patient with endogenous Cushing's syndrome secondary to an adrenocortical carcinoma, who developed concomitant disseminated cryptococcosis and candidiasis in the course of his disease. PMID:24470886

  7. Endogenous Money Supply and Money Demand

    OpenAIRE

    Woon Gyu Choi; Seonghwan Oh

    2000-01-01

    This paper explores the behavior of money demand by explicitly accounting for the money supply endogeneity arising from endogenous monetary policy and financial innovations. Our theoretical analysis indicates that money supply factors matter in the money demand function when the money supply partially responds to money demand. Our empirical results with U.S. data provide strong evidence for the relevance of the policy stance to the demand for MI under a regime in which monetary policy is subs...

  8. Ciliary neurotrophic factor is an endogenous pyrogen.

    Science.gov (United States)

    Shapiro, L; Zhang, X X; Rupp, R G; Wolff, S M; Dinarello, C A

    1993-09-15

    Fever is initiated by the action of polypeptide cytokines called endogenous pyrogens, which are produced by the host during inflammation, trauma, or infection and which elevate the thermoregulatory set point in the hypothalamus. Ciliary neurotrophic factor (CNTF) supports the differentiation and survival of central and peripheral neurons. We describe the activity of CNTF as intrinsically pyrogenic in the rabbit. CNTF induced a monophasic fever which rose rapidly (within the first 12 min) following intravenous injection; CNTF fever was blocked by pretreatment with indomethacin. The fever induced by CNTF was not due to contaminating endotoxins. Increasing doses of CNTF resulted in prolongation of the fever, suggesting the subsequent induction of additional endogenous pyrogenic activity. After passive transfer of plasma obtained during CNTF-induced fever, endogenous pyrogen activity was not present in the circulation; CNTF also did not induce the endogenous pyrogens interleukin 1, tumor necrosis factor, or interleukin 6 in vitro. Nevertheless, a second endogenous pyrogen may originate within the central nervous system following the systemic injection of CNTF. Of the four endogenous pyrogens described to date (interleukin 1, tumor necrosis factor, interferon, and interleukin 6), CNTF, like interleukin 6, utilizes the cell-surface gp 130 signal-transduction apparatus.

  9. Activation of an endogenous retrotransposon associated with epigenetic changes in Lotus japonicus

    DEFF Research Database (Denmark)

    Fukai, Eigo; Stougaard, Jens; Hayashi, Makoto

    2013-01-01

    Long terminal repeat retrotransposons occupy a large portion of genomes in flowering plants. In spite of their abundance, the majority are silenced and rarely transpose. One of the examples of a highly active retrotransposon is Lotus Retrotransposon 1(LORE1), of the model legume Lotus japonicus...... significance of LORE1 as a member of chromovirus, a chromodomain containing clade of the Gypsy superfamily. Then we discuss possibilities and methodologies for using endogenous transposable elements as mutagens to generate gene tagging populations in plants...

  10. Anionic lipids and the maintenance of membrane electrostatics in eukaryotes.

    Science.gov (United States)

    Platre, Matthieu Pierre; Jaillais, Yvon

    2017-02-01

    A wide range of signaling processes occurs at the cell surface through the reversible association of proteins from the cytosol to the plasma membrane. Some low abundant lipids are enriched at the membrane of specific compartments and thereby contribute to the identity of cell organelles by acting as biochemical landmarks. Lipids also influence membrane biophysical properties, which emerge as an important feature in specifying cellular territories. Such parameters are crucial for signal transduction and include lipid packing, membrane curvature and electrostatics. In particular, membrane electrostatics specifies the identity of the plasma membrane inner leaflet. Membrane surface charges are carried by anionic phospholipids, however the exact nature of the lipid(s) that powers the plasma membrane electrostatic field varies among eukaryotes and has been hotly debated during the last decade. Herein, we discuss the role of anionic lipids in setting up plasma membrane electrostatics and we compare similarities and differences that were found in different eukaryotic cells.

  11. Differentiation of endogenous and exogenous steroids by gas chromatography-combustion-mass spectrometry isotope ratio

    International Nuclear Information System (INIS)

    Montes de Oca Porto, Rodny; Rosado Perez, Aristides; Correa Vidal, Margarita Teresa

    2007-01-01

    Urinary steroids profiles are used to control the misuse of endogenous steroids such as testosterone and dihydrotestosterone. The testosterone/epistestosterone ratio, measured by Gas Chromatography-Mass Spectrometry, is used to control testosterone administration. When T/E ratio is higher than 4, consumption of testosterone or its precursors is suspected. Recent researches have demonstrated the effectiveness of Carbon Isotope Ratio Mass Spectrometry to detect and confirm endogenous steroids administration. The ratio of the two stable carbon isotopes 1 3 C and 1 2 C allows the differentiation of natural and synthetic steroids because synthetic steroids have lower 1 3 C abundance. In fact, the carbon isotope ratios can be used to determine endogenous steroids administration even when testosterone/epistestosterone ratio is at its normal value. In the current work, some of the most important aspects related to differentiation of endogenous and exogenous steroids by means of Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry are discussed. Also, this article provides a review about the purification and sample preparation previous to the analysis, and diet effects on carbon isotope ratio of endogenous anabolics steroids is presented too

  12. Lipid exchange by ultracentrifugation

    DEFF Research Database (Denmark)

    Drachmann, Nikolaj Düring; Olesen, Claus

    2014-01-01

    , and the complex interplay between the lipids and the P-type ATPases are still not well understood. We here describe a robust method to exchange the majority of the lipids surrounding the ATPase after solubilisation and/or purification with a target lipid of interest. The method is based on an ultracentrifugation...... step, where the protein sample is spun through a dense buffer containing large excess of the target lipid, which results in an approximately 80-85 % lipid exchange. The method is a very gently technique that maintains protein folding during the process, hence allowing further characterization...

  13. Energy abundance and economic progress

    International Nuclear Information System (INIS)

    Schurr, S.H.

    1983-01-01

    A discussion is presented on the benefits of energy abundance and on the links between energy supply, economic growth and human welfare in the United States. It is argued that the restoration of energy abundance with dependable sources of supply should be a major national objective. (U.K.)

  14. Abundances in the Galactic bulge

    Energy Technology Data Exchange (ETDEWEB)

    Barbuy, B; Alves-Brito, A [Universidade de Sao Paulo, IAG, Rua do Matao 1226, Sao Paulo 05508-900 (Brazil); Ortolani, S; Zoccali, M [Dipartimento di Astronomia, Universita di Padova, Vicolo dell' Osservatorio 2, I-35122 Padova (Italy); Hill, V; Gomez, A [Observatoire de Paris-Meudon, 92195 Meudon Cedex (France); Melendez, J [Centro de AstrofIsica da Universidade de Porto, Rua das Estrelas, 4150-762 Porto (Portugal); Asplund, M [Max Planck Institute for Astrophysics, Postfach 1317, 85741 Garching (Germany); Bica, E [Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, CP 15051, Porto Alegre 91501-970 (Brazil); Renzini, A [Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Minniti, D [Department of Astronomy and Astrophysics, Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile)], E-mail: barbuy@astro.iag.usp.br

    2008-12-15

    The metallicity distribution and abundance ratios of the Galactic bulge are reviewed. Issues raised by recent work of different groups, in particular the high metallicity end, the overabundance of {alpha}-elements in the bulge relative to the thick disc and the measurement of giants versus dwarfs, are discussed. Abundances in the old moderately metal-poor bulge globular clusters are described.

  15. Lipid Structure in Triolein Lipid Droplets

    DEFF Research Database (Denmark)

    Chaban, Vitaly V; Khandelia, Himanshu

    2014-01-01

    of a mass of hydrophobic lipid esters coved by phospholipid monolayer. The small size and unique architecture of LDs makes it complicated to study LD structure by modern experimental methods. We discuss coarse-grained molecular dynamics (MD) simulations of LD formation in systems containing 1-palmitoyl-2...... to coarse-grained simulations, the presence of PE lipids at the interface has a little impact on distribution of components and on the overall LD structure. (4) The thickness of the lipid monolayer at the surface of the droplet is similar to the thickness of one leaflet of a bilayer. Computer simulations......Lipid droplets (LDs) are primary repositories of esterified fatty acids and sterols in animal cells. These organelles originate on the lumenal or cytoplasmic side of endoplasmic reticulum (ER) membrane and are released to the cytosol. In contrast to other intracellular organelles, LDs are composed...

  16. Host-virus interactions of mammalian endogenous retroviruses

    OpenAIRE

    Farkašová, Helena

    2017-01-01

    Endogenous retroviruses (ERVs) originate by germline infection and subsequent mendelian inheritance of their exogenous counterparts. With notable exceptions, all mammalian ERVs are evolutionarily old and fixed in the population of its host species. Some groups of retroviruses were believed not to be able to form endogenous copies. We discovered an additional endogenous Lentivirus and a first endogenous Deltaretrovirus. Both of these groups were previously considered unable to form endogenous ...

  17. [The endogenous opioid system and drug addiction].

    Science.gov (United States)

    Maldonado, R

    2010-01-01

    Drug addiction is a chronic brain disorder leading to complex adaptive changes within the brain reward circuits. Several neurotransmitters, including the endogenous opioid system are involved in these changes. The opioid system plays a pivotal role in different aspects of addiction. Thus, opioid receptors and endogenous opioid peptides are largely distributed in the mesolimbic system and modulate dopaminergic activity within the reward circuits. Opioid receptors and peptides are selectively involved in several components of the addictive processes induced by opioids, cannabinoids, psychostimulants, alcohol and nicotine. This review is focused on the contribution of each component of the endogenous opioid system in the addictive properties of the different drugs of abuse. Copyright 2010 Elsevier Masson SAS. All rights reserved.

  18. Endogenous vs. exogenous regulations in the commons

    DEFF Research Database (Denmark)

    Abatayo, Anna Lou; Lynham, John

    2016-01-01

    It is widely believed that there is strong experimental evidence to support the idea that exogenously imposed regulations crowd out the intrinsic motivations of common pool resource (CPR) users to refrain from over-harvesting. We introduce a novel experimental design that attempts to disentangle...... potential confounds in previous experiments. A key feature of our experimental design is to have the exact same regulations chosen endogenously as those that are imposed exogenously. When we compare the same regulations chosen endogenously to those externally imposed, we observe no differences in extraction...... endogenous regulations with communication and exogenous regulations without communication. Our results suggest that externally imposed regulations do not crowd out intrinsic motivations in the lab and they confirm that communication facilitates cooperation to reduce extraction....

  19. Feeding Releases Endogenous Opioids in Humans.

    Science.gov (United States)

    Tuulari, Jetro J; Tuominen, Lauri; de Boer, Femke E; Hirvonen, Jussi; Helin, Semi; Nuutila, Pirjo; Nummenmaa, Lauri

    2017-08-23

    The endogenous opioid system supports a multitude of functions related to appetitive behavior in humans and animals, and it has been proposed to govern hedonic aspects of feeding thus contributing to the development of obesity. Here we used positron emission tomography to investigate whether feeding results in hedonia-dependent endogenous opioid release in humans. Ten healthy males were recruited for the study. They were scanned with the μ-opioid-specific ligand [ 11 C]carfentanil three times, as follows: after a palatable meal, a nonpalatable meal, and after an overnight fast. Subjective mood, satiety, and circulating hormone levels were measured. Feeding induced significant endogenous opioid release throughout the brain. This response was more pronounced following a nonpalatable meal versus a palatable meal, and independent of the subjective hedonic responses to feeding. We conclude that feeding consistently triggers cerebral opioid release even in the absence of subjective pleasure associated with feeding, suggesting that metabolic and homeostatic rather than exclusively hedonic responses play a role in the feeding-triggered cerebral opioid release. SIGNIFICANCE STATEMENT The endogenous opioid system supports both hedonic and homeostatic functions. It has been proposed that overeating and concomitant opioid release could downregulate opioid receptors and promote the development of obesity. However, it remains unresolved whether feeding leads to endogenous opioid release in humans. We used in vivo positron emission tomography to test whether feeding triggers cerebral opioid release and whether this response is associated with pleasurable sensations. We scanned volunteers using the μ-opioid receptor-specific radioligand [ 11 C]carfentanil three times, as follows: after an overnight fast, after consuming a palatable meal, and after consuming a nonpalatable meal. Feeding led to significant endogenous opioid release, and this occurred also in the absence of feeding

  20. Endogenous network of firms and systemic risk

    Science.gov (United States)

    Ma, Qianting; He, Jianmin; Li, Shouwei

    2018-02-01

    We construct an endogenous network characterized by commercial credit relationships connecting the upstream and downstream firms. Simulation results indicate that the endogenous network model displays a scale-free property which exists in real-world firm systems. In terms of the network structure, with the expansion of the scale of network nodes, the systemic risk increases significantly, while the heterogeneities of network nodes have no effect on systemic risk. As for firm micro-behaviors, including the selection range of trading partners, actual output, labor requirement, price of intermediate products and employee salaries, increase of all these parameters will lead to higher systemic risk.

  1. Endogenous Generalized Weights under DEA Control

    DEFF Research Database (Denmark)

    Agrell, Per J.; Bogetoft, Peter

    Non-parametric efficiency analysis, such as Data Envelopment Analysis (DEA) relies so far on endogenous local or exogenous general weights, based on revealed preferences or market prices. However, as DEA is gaining popularity in regulation and normative budgeting, the strategic interest...... of the evaluated industry calls for attention. We offer endogenous general prices based on a reformulation of DEA where the units collectively propose the set of weights that maximize their efficiency. Thus, the sector-wide efficiency is then a result of compromising the scores of more specialized smaller units...

  2. An endogenous model of the credit network

    Science.gov (United States)

    He, Jianmin; Sui, Xin; Li, Shouwei

    2016-01-01

    In this paper, an endogenous credit network model of firm-bank agents is constructed. The model describes the endogenous formation of firm-firm, firm-bank and bank-bank credit relationships. By means of simulations, the model is capable of showing some obvious similarities with empirical evidence found by other scholars: the upper-tail of firm size distribution can be well fitted with a power-law; the bank size distribution can be lognormally distributed with a power-law tail; the bank in-degrees of the interbank credit network as well as the firm-bank credit network fall into two-power-law distributions.

  3. Animal spirits, competitive markets, and endogenous growth

    Science.gov (United States)

    Miyazaki, Kenji

    2013-10-01

    This paper uses a simple model with an endogenous discount rate and linear technology to investigate whether a competitive equilibrium has a higher balanced growth path (BGP) than the social planning solution and whether the BGP is determinate or indeterminate. The implications are as follows. To start with, people with an instinct to compare themselves with others possess an endogenous discount rate. In turn, this instinct affects the economic growth rate in a competitive market economy. The competitive market economy also sometimes achieves higher economic growth than a social planning economy. However, the outcomes of market economy occasionally fluctuate because of the presence of the self-fulfilling prophecy or animal spirits.

  4. [Mechanisms of leukocyte formation of endogenous pyrogen].

    Science.gov (United States)

    Rybakina, E G; Sorokin, A V

    1982-06-01

    A study was made of the kinetics of endogenous pyrogen production by rabbit blood and exudate leukocytes and possible role played by the products of activated leukocytes in autoregulation of the process. It was established that accumulation of endogenous pyrogen in the cell precedes its release by stimulated cells. Then the processes of active pyrogen formation and release gel interdependent: pyrogen formed releases from the cell; the lowering of pyrogen concentration in the cell is accompanied by the decrease of its content in the medium. No stimulating effect of the products activated during leukocyte inflammation on pyrogen formation by blood leukocytes was discovered.

  5. Oxygen abundances in halo stars

    Science.gov (United States)

    Bessell, Michael S.; Sutherland, Ralph S.; Ruan, Kui

    1991-12-01

    The present study determines the oxygen abundance for a sample of metal-poor G dwarfs by analysis of OH lines between 3080 and 3200 A and the permitted high-excitation far-red O I triple. The oxygen abundances determined from the low-excitation OH lines are up to 0.55 dex lower than those measured from the high-excitation O I lines. The abundances for the far-red O I triplet lines agree with those rederived from Abia and Rebolo (1989), and the abundances from the OH lines in dwarfs and giants are in agreement with the rederived O abundances of Barbuy (1988) and others from the forbidden resonance O I line. Because the chi = 0.1.7 eV OH lines are formed in the same layers as the majority of Fe, Ti, and other neutral metal lines used for abundance analyses, it is argued that the OH lines and the forbidden O I line yield the true oxygen abundances relative to the metals.

  6. Lipofection indirectly increases expression of endogenous major histocompatibility complex class I molecules on tumor cells.

    Science.gov (United States)

    Fox, B A; Drury, M; Hu, H M; Cao, Z; Huntzicker, E G; Qie, W; Urba, W J

    1998-01-01

    Direct intratumoral injection of a lipid/DNA complex encoding an allogeneic major histocompatibility complex (MHC) class I molecule leads to regression of both an immunogenic murine tumor and also melanoma lesions in some patients. We have sought to understand the mechanism(s) for this augmentation of antitumor activity. While optimizing parameters for in vitro gene transfer into the D5 subclone of B16BL6, it was noted that lipofected tumors not only expressed the new alloantigen but also exhibited increased expression of endogenous MHC class I, both H-2 Kb and H-2 Db. This increase in expression was not restricted to the small percentage of cells that expressed the transfected gene, but appeared to affect the majority of cells in culture. Class I expression was not increased by lipopolysaccharide, DNA alone, lipid, or lipid/lipopolysaccharide mixtures. Enhanced class I expression required a DNA/lipid complex and was greatest when parameters optimized for gene transfer of the alloantigen were used. All DNA plasmids tested had this effect, including one plasmid whose DNA was not transcribed because it lacked an expression cassette. Because of the critical role that MHC class I antigens play in immune recognition, we propose that lipid complex-mediated gene transfer may provide immunological advantages beyond those that are attributable to expression of the specific gene transferred.

  7. Endogenous MOV10 inhibits the retrotransposition of endogenous retroelements but not the replication of exogenous retroviruses

    Science.gov (United States)

    2012-01-01

    Background The identification of cellular factors that regulate the replication of exogenous viruses and endogenous mobile elements provides fundamental understanding of host-pathogen relationships. MOV10 is a superfamily 1 putative RNA helicase that controls the replication of several RNA viruses and whose homologs are necessary for the repression of endogenous mobile elements. Here, we employ both ectopic expression and gene knockdown approaches to analyse the role of human MOV10 in the replication of a panel of exogenous retroviruses and endogenous retroelements. Results MOV10 overexpression substantially decreased the production of infectious retrovirus particles, as well the propagation of LTR and non-LTR endogenous retroelements. Most significantly, RNAi-mediated silencing of endogenous MOV10 enhanced the replication of both LTR and non-LTR endogenous retroelements, but not the production of infectious retrovirus particles demonstrating that natural levels of MOV10 suppress retrotransposition, but have no impact on infection by exogenous retroviruses. Furthermore, functional studies showed that MOV10 is not necessary for miRNA or siRNA-mediated mRNA silencing. Conclusions We have identified novel specificity for human MOV10 in the control of retroelement replication and hypothesise that MOV10 may be a component of a cellular pathway or process that selectively regulates the replication of endogenous retroelements in somatic cells. PMID:22727223

  8. Endogenous MOV10 inhibits the retrotransposition of endogenous retroelements but not the replication of exogenous retroviruses.

    Science.gov (United States)

    Arjan-Odedra, Shetal; Swanson, Chad M; Sherer, Nathan M; Wolinsky, Steven M; Malim, Michael H

    2012-06-22

    The identification of cellular factors that regulate the replication of exogenous viruses and endogenous mobile elements provides fundamental understanding of host-pathogen relationships. MOV10 is a superfamily 1 putative RNA helicase that controls the replication of several RNA viruses and whose homologs are necessary for the repression of endogenous mobile elements. Here, we employ both ectopic expression and gene knockdown approaches to analyse the role of human MOV10 in the replication of a panel of exogenous retroviruses and endogenous retroelements. MOV10 overexpression substantially decreased the production of infectious retrovirus particles, as well the propagation of LTR and non-LTR endogenous retroelements. Most significantly, RNAi-mediated silencing of endogenous MOV10 enhanced the replication of both LTR and non-LTR endogenous retroelements, but not the production of infectious retrovirus particles demonstrating that natural levels of MOV10 suppress retrotransposition, but have no impact on infection by exogenous retroviruses. Furthermore, functional studies showed that MOV10 is not necessary for miRNA or siRNA-mediated mRNA silencing. We have identified novel specificity for human MOV10 in the control of retroelement replication and hypothesise that MOV10 may be a component of a cellular pathway or process that selectively regulates the replication of endogenous retroelements in somatic cells.

  9. Optimal income taxation with endogenous human capital

    NARCIS (Netherlands)

    Jacobs, B.

    2005-01-01

    This paper augments the theory of optimal linear income taxation by taking into account human capital accumulation as a dimension of labor supply. The distribution of earning potentials is endogenous because agents differ in the ability to learn. Taxation affects utilization rates of human capital

  10. Essays on Policy Evaluation with Endogenous Adoption

    Science.gov (United States)

    Gentile, Elisabetta

    2011-01-01

    Over the last decade, experimental and quasi-experimental methods have been favored by researchers in empirical economics, as they provide unbiased causal estimates. However, when implementing a program, it is often not possible to randomly assign subjects to treatment, leading to a possible endogeneity bias. This dissertation consists of two…

  11. Place branding, embeddedness and endogenous rural development

    NARCIS (Netherlands)

    Donner, Mechthild; Horlings, Lummina; Fort, Fatiha; Vellema, Sietze

    2017-01-01

    This article deals with place branding on the regional scale, in the rural context of food and tourism networks in Europe. Place branding is linked to the concepts of endogenous rural development, territory and embeddedness, by analysing how the valorisation of specific rural assets takes shape.

  12. Climate changes and farmers' endogenous adaptation strategies ...

    African Journals Online (AJOL)

    It has been claimed that climate changes impact studies often assume certain adaptations and little explicit examination of how, when, why, and under what conditions they occur. This research aims at analysing the endogenous strategies developed by farmers in agricultural land and crop management. With random ...

  13. Endogenous thrombin potential in polycystic ovary syndrome

    DEFF Research Database (Denmark)

    Aziz, Mubeena; Sidelmann, Johannes Jakobsen; Wissing, Marie Louise Muff

    2015-01-01

    OBJECTIVES: The objective of this study is to investigate plasma endogenous thrombin generation in four different phenotypes of polycystic ovary syndrome (PCOS) defined by Body Mass Index (BMI) and insulin resistance (IR). PCOS is diagnosed according to the Rotterdam criteria. DESIGN: Multicenter...

  14. Immigration, Endogenous Technology Adoption and Wages

    NARCIS (Netherlands)

    Ray Chaudhuri, A.; Pandey, Manish

    2015-01-01

    We document that immigration to U.S. states has increased the mass of workers at the lower range of the skill distribution. We use this change in skill distribution of workers to analyze the effect of immigration on wages. Our model allows firms to endogenously respond to the immigration-induced

  15. HERVd: the Human Endogenous Retrovirus Database: update

    Czech Academy of Sciences Publication Activity Database

    Pačes, Jan; Pavlíček, A.; Zíka, Radek; Jurka, J.; Pačes, Václav

    2004-01-01

    Roč. 32, č. 1 (2004), s. 50-50 ISSN 0305-1048 R&D Projects: GA MŠk LN00A079 Institutional research plan: CEZ:AV0Z5052915 Keywords : human * endogenous retrovirus * database Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.260, year: 2004

  16. Endogenous Quality Effects of Trade Policy

    NARCIS (Netherlands)

    J.L. Moraga-Gonzalez (José Luis); J.M.A. Viaene (Jean-Marie)

    1999-01-01

    textabstractWe study the optimal trade policy against a foreign oligopoly with endogenous quality. We show that, under the Most Favoured Nation (MFN) clause, a uniform tariff policy is always welfare improving over the free trade equilibrium. However, a nonuniform tariff policy is always desirable

  17. Optimized Formation of Benzyl Isothiocyanate by Endogenous ...

    African Journals Online (AJOL)

    Purpose: To use endogenous myrosinase in Carica papaya seed to convert benzyl glucosinolate (BG) to benzyl isothiocyanate (BITC) and then extract it for further studies. Methods: Process variables including seed powder particle size, sample-to-solvent ratio, pH of buffer solution, enzymolysis temperature, enzymolysis ...

  18. Structural classification of endogenous regulatory oligopeptides.

    Science.gov (United States)

    Zamyatnin, A A

    1991-07-01

    Based on the criteria of 50% identity in the amino acid sequence, a new method for grouping endogenous regulatory oligopeptides into structural families is presented. Data from the EROP-Moscow data bank on 579 oligopeptides fitting a preset spectrum of functional activities revealed 73 structural oligopeptide groups, 36 of which were called families.

  19. Endogenous retrovirus sequences expressed in male mammalian ...

    African Journals Online (AJOL)

    Objectives: To review the research findings on the expression of endogenous retroviruses and retroviral-related particles in male mammalian reproductive tissues, and to discuss their possible role in normal cellular events and association with disease conditions in male reproductive tissues. Data sources: Published ...

  20. The Limit of Public Policy : Endogenous Preferences

    NARCIS (Netherlands)

    Bar-Gill, O.; Fershtman, C.

    2000-01-01

    In designing public policy it is not enough to consider the possible reaction of individuals to the chosen policy.Public policy may also affect the formation of preferences and norms in a society.The endogenous evolution of preferences, in addition to introducing a conceptual difficulty in

  1. Endogeneity in Strategy-Performance Analysis

    DEFF Research Database (Denmark)

    Rocha, Vera; Van Praag, Mirjam; B. Folta, Timothy

    2018-01-01

    , such as employees, strategic partners, customers, or investors, whose choices and preferences also affect the final decision. We discuss how endogeneity can plague the measurement of the performance effects of these two-sided strategic decisions—which are more complex, but more realistic, than prior representations...

  2. Managing spillovers: an endogenous sunk cost approach

    Czech Academy of Sciences Publication Activity Database

    Senyuta, Olena; Žigić, Krešimir

    2016-01-01

    Roč. 35, June (2016), s. 45-64 ISSN 0167-6245 R&D Projects: GA ČR(CZ) GAP402/12/0961 Institutional support: PRVOUK-P23 Keywords : endogenous sunk costs * innovations * knowledge spillovers Subject RIV: AH - Economics Impact factor: 0.739, year: 2016

  3. Applying Endogenous Knowledge in the African Context ...

    African Journals Online (AJOL)

    This requires not only an understanding of what endogenous knowledge is, but also an alignment of personal values, innovative strategies and an attitude of activism. An integral part of an extensive skills set to implement specifi c dispute resolution strategies is the ability to facilitate the free sharing of information about all ...

  4. [Endogenous pyrogen formation by bone marrow cells].

    Science.gov (United States)

    Efremov, O M; Sorokin, A V; El'kina, O A

    1978-01-01

    The cells of the rabbit bone marrow produced endogenous pyrogen in response to stimulation with bacterial lipopolysaccharide. Incubation of the cells in medium No 199 containing a 15% homologous serum is optimal for the release of pyrogen. It is supposed that the cells of the bone marrow take part in the formation of endgenous pyrogen and in the mechanism of pyrexia in the organism.

  5. Endogenous Cholesterol Excretion Is Negatively Associated With Carotid Intima-Media Thickness in Humans.

    Science.gov (United States)

    Lin, Xiaobo; Racette, Susan B; Ma, Lina; Wallendorf, Michael; Dávila-Román, Victor G; Ostlund, Richard E

    2017-12-01

    Epidemiological studies strongly suggest that lipid factors independent of low-density lipoprotein cholesterol contribute significantly to cardiovascular disease risk. Because circulating lipoproteins comprise only a small fraction of total body cholesterol, the mobilization and excretion of cholesterol from plasma and tissue pools may be an important determinant of cardiovascular disease risk. Our hypothesis is that fecal excretion of endogenous cholesterol is protective against atherosclerosis. Cholesterol metabolism and carotid intima-media thickness were quantitated in 86 nondiabetic adults. Plasma cholesterol was labeled by intravenous infusion of cholesterol-d 7 solubilized in a lipid emulsion and dietary cholesterol by cholesterol-d 5 and the nonabsorbable stool marker sitostanol-d 4 . Plasma and stool samples were collected while subjects consumed a cholesterol- and phytosterol-controlled metabolic kitchen diet and were analyzed by mass spectrometry. Carotid intima-media thickness was negatively correlated with fecal excretion of endogenous cholesterol ( r =-0.426; P cholesterol ( r =-0.472; P ≤0.0001), and daily percent excretion of cholesterol from the rapidly mixing cholesterol pool ( r =-0.343; P =0.0012) and was positively correlated with percent cholesterol absorption ( r =+0.279; P =0.0092). In a linear regression model controlling for age, sex, systolic blood pressure, hemoglobin A1c, low-density lipoprotein, high-density lipoprotein cholesterol, and statin drug use, fecal excretion of endogenous cholesterol remained significant ( P =0.0008). Excretion of endogenous cholesterol is strongly, independently, and negatively associated with carotid intima-media thickness. The reverse cholesterol transport pathway comprising the intestine and the rapidly mixing plasma, and tissue cholesterol pool could be an unrecognized determinant of cardiovascular disease risk not reflected in circulating lipoproteins. Further work is needed to relate measures of

  6. Spectral unmixing: estimating partial abundances

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2009-01-01

    Full Text Available techniques is complicated when considering very similar spectral signatures. Iron-bearing oxide/hydroxide/sulfate minerals have similar spectral signatures. The study focuses on how could estimates of abundances of spectrally similar iron-bearing oxide...

  7. Ammonia abundances in four comets

    International Nuclear Information System (INIS)

    Wickoff, S.; Tegler, S.C.; Engel, L.

    1991-01-01

    NH2 emission band strengths were measured in four comets and the NH2 column densities were determined in order to measure the ammonia content of the comets. The mean ammonia/water abundance ratio derived for the four comets is found to be 0.13 + or - 0.06 percent, with no significant variation among the comets. The uniformity of this abundance attests to a remarkable degree of chemical homogeneity over large scales in the comet-forming region of the primordial solar nebula, and contrasts with the CO abundance variations found previously in comets. The N2 and NH3 abundances indicate a condensation temperature in the range 20-160 K, consistent with virtually all comet formation hypotheses. 64 refs

  8. Magellanic Clouds Cepheids: Thorium Abundances

    Directory of Open Access Journals (Sweden)

    Yeuncheol Jeong

    2018-03-01

    Full Text Available The analysis of the high-resolution spectra of 31 Magellanic Clouds Cepheid variables enabled the identification of thorium lines. The abundances of thorium were found with spectrum synthesis method. The calculated thorium abundances exhibit correlations with the abundances of other chemical elements and atmospheric parameters of the program stars. These correlations are similar for both Clouds. The correlations of iron abundances of thorium, europium, neodymium, and yttrium relative to the pulsational periods are different in the Large Magellanic Cloud (LMC and the Small Magellanic Cloud (SMC, namely the correlations are negative for LMC and positive or close to zero for SMC. One of the possible explanations can be the higher activity of nucleosynthesis in SMC with respect to LMC in the recent several hundred million years.

  9. NEFSC Survey Indices of Abundance

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Northeast Fisheries Survey Bottom trawl survey indices of abundance such as stratified mean number per tow or mean weight per tow by species stock. Includes indices...

  10. ENDOGENOUS ANALGESIA, DEPENDENCE, AND LATENT PAIN SENSITIZATION

    Science.gov (United States)

    Taylor, Bradley K; Corder, Gregory

    2015-01-01

    Endogenous activation of μ-opioid receptors (MORs) provides relief from acute pain. Recent studies have established that tissue inflammation produces latent pain sensitization (LS) that is masked by spinal MOR signaling for months, even after complete recovery from injury and re-establishment of normal pain thresholds. Disruption with MOR inverse agonists reinstates pain and precipitates cellular, somatic and aversive signs of physical withdrawal; this phenomenon requires N-methyl-D-aspartate receptor-mediated activation of calcium-sensitive adenylyl cyclase type 1 (AC1). In this review, we present a new conceptual model of the transition from acute to chronic pain, based on the delicate balance between LS and endogenous analgesia that develops after painful tissue injury. First, injury activates pain pathways. Second, the spinal cord establishes MOR constitutive activity (MORCA) as it attempts to control pain. Third, over time, the body becomes dependent on MORCA, which paradoxically sensitizes pain pathways. Stress or injury escalates opposing inhibitory and excitatory influences on nociceptive processing as a pathological consequence of increased endogenous opioid tone. Pain begets MORCA begets pain vulnerability in a vicious cycle. The final result is a silent insidious state characterized by the escalation of two opposing excitatory and inhibitory influences on pain transmission: LS mediated by AC1 (which maintains accelerator), and pain inhibition mediated by MORCA (which maintains the brake). This raises the prospect that opposing homeostatic interactions between MORCA analgesia and latent NMDAR–AC1-mediated pain sensitization create a lasting vulnerability to develop chronic pain. Thus, chronic pain syndromes may result from a failure in constitutive signaling of spinal MORs and a loss of endogenous analgesic control. An overarching long-term therapeutic goal of future research is to alleviate chronic pain by either: a) facilitating endogenous opioid

  11. Endogenous Phenolics in Hulls and Cotyledons of Mustard and Canola: A Comparative Study on Its Sinapates and Antioxidant Capacity

    OpenAIRE

    Mayengbam, Shyamchand; Aachary, Ayyappan; Thiyam-Holländer, Usha

    2014-01-01

    Endogenous sinapic acid (SA), sinapine (SP), sinapoyl glucose (SG) and canolol (CAN) of canola and mustard seeds are the potent antioxidants in various lipid-containing systems. The study investigated these phenolic antioxidants using different fractions of canola and mustard seeds. Phenolic compounds were extracted from whole seeds and their fractions: hulls and cotyledons, using 70% methanol by the ultrasonication method and quantified using HPLC-DAD. The major phenolics from both hulls and...

  12. Zebrafish Embryonic Lipidomic Analysis Reveals that the Yolk Cell Is Metabolically Active in Processing Lipid

    Directory of Open Access Journals (Sweden)

    Daniel Fraher

    2016-02-01

    Full Text Available The role of lipids in providing energy and structural cellular components during vertebrate development is poorly understood. To elucidate these roles further, we visualized lipid deposition and examined expression of key lipid-regulating genes during zebrafish embryogenesis. We also conducted a semiquantitative analysis of lipidomic composition using liquid chromatography (LC-mass spectrometry. Finally, we analyzed processing of boron-dipyrromethene (BODIPY lipid analogs injected into the yolk using thin layer chromatography. Our data reveal that the most abundant lipids in the embryo are cholesterol, phosphatidylcholine, and triglyceride. Moreover, we demonstrate that lipids are processed within the yolk prior to mobilization to the embryonic body. Our data identify a metabolically active yolk and body resulting in a dynamic lipid composition. This provides a foundation for studying lipid biology during normal or pharmacologically compromised embryogenesis.

  13. Polyene-lipids: a new tool to image lipids

    DEFF Research Database (Denmark)

    Kuerschner, Lars; Ejsing, Christer S.; Ekroos, Kim

    2005-01-01

    conjugated double bonds as a new type of lipid tag. Polyene-lipids exhibit a unique structural similarity to natural lipids, which results in minimal effects on the lipid properties. Analyzing membrane phase partitioning, an important biophysical and biological property of lipids, we demonstrated......Microscopy of lipids in living cells is currently hampered by a lack of adequate fluorescent tags. The most frequently used tags, NBD and BODIPY, strongly influence the properties of lipids, yielding analogs with quite different characteristics. Here, we introduce polyene-lipids containing five...... the superiority of polyene-lipids to both NBD- and BODIPY-tagged lipids. Cells readily take up various polyene-lipid precursors and generate the expected end products with no apparent disturbance by the tag. Applying two-photon excitation microscopy, we imaged the distribution of polyene-lipids in living...

  14. Bioactive Lipids and Chronic Inflammation: Managing the Fire Within

    Directory of Open Access Journals (Sweden)

    Valerio Chiurchiù

    2018-01-01

    Full Text Available Inflammation is an immune response that works as a contained fire that is pre-emptively sparked as a defensive process during infections or upon any kind of tissue insult, and that is spontaneously extinguished after elimination or termination of the damage. However, persistent and uncontrolled immune reactions act as a wildfire that promote chronic inflammation, unresolved tissue damage and, eventually, chronic diseases. A wide network of soluble mediators, among which endogenous bioactive lipids, governs all immune processes. They are secreted by basically all cells involved in inflammatory processes and constitute the crucial infrastructure that triggers, coordinates and confines inflammatory mechanisms. However, these molecules are also deeply involved in the detrimental transition from acute to chronic inflammation, be it for persistent or excessive action of pro-inflammatory lipids or for the impairment of the functions carried out by resolving ones. As a matter of fact, bioactive lipids have been linked, to date, to several chronic diseases, including rheumatoid arthritis, atherosclerosis, diabetes, cancer, inflammatory bowel disease, systemic lupus erythematosus, and multiple sclerosis. This review summarizes current knowledge on the involvement of the main classes of endogenous bioactive lipids—namely classical eicosanoids, pro-resolving lipid mediators, lysoglycerophospholipids/sphingolipids, and endocannabinoids—in the cellular and molecular mechanisms that lead to the pathogenesis of chronic disorders.

  15. The evolution of lipids

    Science.gov (United States)

    Itoh, Y. H.; Sugai, A.; Uda, I.; Itoh, T.

    2001-01-01

    Living organisms on the Earth which are divided into three major domains - Archaea, Bacteria, and Eucarya, probably came from a common ancestral cell. Because there are many thermophilic microorganisms near the root of the universal phylogenetic tree, the common ancestral cell should be considered to be a thermophilic microorganism. The existence of a cell is necessary for the living organisms; the cell membrane is the essential structural component of a cell, so its amphiphilic property is vital for the molecule of lipids for cell membranes. Tetraether type glycerophospholipids with C 40 isoprenoid chains are major membrane lipids widely distributed in archaeal cells. Cyclization number of C 40 isoprenoid chains in thermophilic archaea influences the fluidity of lipids whereas the number of carbons and degree of unsaturation in fatty acids do so in bacteria and eucarya. In addition to the cyclization of the tetraether lipids, covalent bonding of two C 40 isoprenoid chains was found in hyperthermophiles. These characteristic structures of the lipids seem to contribute to their fundamental physiological roles in hyperthermophiles. Stereochemical differences between G-1-P archaeal lipids and G-3-P bacterial and eucaryal lipids might have occured by the function of some proteins long after the first cell was developed by the reactions of small organic molecules. We propose that the structure of lipids of the common ancestral cell may have been similar to those of hyperthermophilic archaea.

  16. Lysosomal lipid storage diseases.

    Science.gov (United States)

    Schulze, Heike; Sandhoff, Konrad

    2011-06-01

    Lysosomal lipid storage diseases, or lipidoses, are inherited metabolic disorders in which typically lipids accumulate in cells and tissues. Complex lipids, such as glycosphingolipids, are constitutively degraded within the endolysosomal system by soluble hydrolytic enzymes with the help of lipid binding proteins in a sequential manner. Because of a functionally impaired hydrolase or auxiliary protein, their lipid substrates cannot be degraded, accumulate in the lysosome, and slowly spread to other intracellular membranes. In Niemann-Pick type C disease, cholesterol transport is impaired and unesterified cholesterol accumulates in the late endosome. In most lysosomal lipid storage diseases, the accumulation of one or few lipids leads to the coprecipitation of other hydrophobic substances in the endolysosomal system, such as lipids and proteins, causing a "traffic jam." This can impair lysosomal function, such as delivery of nutrients through the endolysosomal system, leading to a state of cellular starvation. Therapeutic approaches are currently restricted to mild forms of diseases with significant residual catabolic activities and without brain involvement.

  17. Lipid bilayers and interfaces

    NARCIS (Netherlands)

    Kik, R.A.

    2007-01-01

    In biological systems lipid bilayers are subject to many different interactions with other entities. These can range from proteins that are attached to the hydrophilic region of the bilayer or transmembrane proteins that interact with the hydrophobic region of the lipid bilayer. Interaction between

  18. Mycobacterium tuberculosis has diminished capacity to counteract redox stress induced by elevated levels of endogenous superoxide.

    Science.gov (United States)

    Tyagi, Priyanka; Dharmaraja, Allimuthu T; Bhaskar, Ashima; Chakrapani, Harinath; Singh, Amit

    2015-07-01

    Mycobacterium tuberculosis (Mtb) has evolved protective and detoxification mechanisms to maintain cytoplasmic redox balance in response to exogenous oxidative stress encountered inside host phagocytes. In contrast, little is known about the dynamic response of this pathogen to endogenous oxidative stress generated within Mtb. Using a noninvasive and specific biosensor of cytoplasmic redox state of Mtb, we for first time discovered a surprisingly high sensitivity of this pathogen to perturbation in redox homeostasis induced by elevated endogenous reactive oxygen species (ROS). We synthesized a series of hydroquinone-based small molecule ROS generators and found that ATD-3169 permeated mycobacteria to reliably enhance endogenous ROS including superoxide radicals. When Mtb strains including multidrug-resistant (MDR) and extensively drug-resistant (XDR) patient isolates were exposed to this compound, a dose-dependent, long-lasting, and irreversible oxidative shift in intramycobacterial redox potential was detected. Dynamic redox potential measurements revealed that Mtb had diminished capacity to restore cytoplasmic redox balance in comparison with Mycobacterium smegmatis (Msm), a fast growing nonpathogenic mycobacterial species. Accordingly, Mtb strains were extremely susceptible to inhibition by ATD-3169 but not Msm, suggesting a functional linkage between dynamic redox changes and survival. Microarray analysis showed major realignment of pathways involved in redox homeostasis, central metabolism, DNA repair, and cell wall lipid biosynthesis in response to ATD-3169, all consistent with enhanced endogenous ROS contributing to lethality induced by this compound. This work provides empirical evidence that the cytoplasmic redox poise of Mtb is uniquely sensitive to manipulation in steady-state endogenous ROS levels, thus revealing the importance of targeting intramycobacterial redox metabolism for controlling TB infection. Copyright © 2015 The Authors. Published by

  19. Development of an enrichment method for endogenous phosphopeptide characterization in human serum.

    Science.gov (United States)

    La Barbera, Giorgia; Capriotti, Anna Laura; Cavaliere, Chiara; Ferraris, Francesca; Laus, Michele; Piovesana, Susy; Sparnacci, Katia; Laganà, Aldo

    2018-01-01

    The work describes the development of an enrichment method for the analysis of endogenous phosphopeptides in serum. Endogenous peptides can play significant biological roles, and some of them could be exploited as future biomarkers. In this context, blood is one of the most useful biofluids for screening, but a systematic investigation of the endogenous peptides, especially phosphorylated ones, is still lacking, mainly due to the lack of suitable analytical methods. Thus, in this paper, different phosphopeptide enrichment strategies were pursued, based either on metal oxide affinity chromatography (MOAC, in the form of commercial TiO 2 spin columns or magnetic graphitized carbon black-TiO 2 composite), or on immobilized metal ion affinity chromatography (IMAC, in the form of Ti 4+ -IMAC magnetic material or commercial Fe 3+ -IMAC spin columns). While MOAC strategies proved completely unsuccessful, probably due to interfering phospholipids displacing phosphopeptides, the IMAC materials performed very well. Different sample preparation strategies were tested, comprising direct dilution with the loading buffer, organic solvent precipitation, and lipid removal from the matrix, as well as the addition of phosphatase inhibitors during sample handling for maximized endogenous phosphopeptide enrichment. All data were acquired by a shotgun peptidomics approach, in which peptide samples were separated by reversed-phase nanoHPLC hyphenated with high-resolution tandem mass spectrometry. The devised method allowed the identification of 176 endogenous phosphopeptides in fresh serum added with inhibitors by the direct dilution protocol and the Ti 4+ -IMAC magnetic material enrichment, but good results could also be obtained from the commercial Fe 3+ -IMAC spin column adapted to the batch enrichment protocol.

  20. Atomic-scale structure and electrostatics of anionic palmitoyloleoylphosphatidylglycerol lipid bilayers with Na+ counterions

    NARCIS (Netherlands)

    Zhao, W.; Róg, T.; Gurtovenko, A.A.; Vattulainen, I.; Karttunen, M.E.J.

    2007-01-01

    Anionic palmitoyloleoylphosphatidylglycerol (POPG) is one of the most abundant lipids in nature, yet its atomic-scale properties have not received significant attention. Here we report extensive 150-ns molecular dynamics simulations of a pure POPG lipid membrane with sodium counterions. It turns out

  1. Carboxylesterases in lipid metabolism: from mouse to human

    Directory of Open Access Journals (Sweden)

    Jihong Lian

    2017-07-01

    Full Text Available ABSTRACT Mammalian carboxylesterases hydrolyze a wide range of xenobiotic and endogenous compounds, including lipid esters. Physiological functions of carboxylesterases in lipid metabolism and energy homeostasis in vivo have been demonstrated by genetic manipulations and chemical inhibition in mice, and in vitro through (overexpression, knockdown of expression, and chemical inhibition in a variety of cells. Recent research advances have revealed the relevance of carboxylesterases to metabolic diseases such as obesity and fatty liver disease, suggesting these enzymes might be potential targets for treatment of metabolic disorders. In order to translate pre-clinical studies in cellular and mouse models to humans, differences and similarities of carboxylesterases between mice and human need to be elucidated. This review presents and discusses the research progress in structure and function of mouse and human carboxylesterases, and the role of these enzymes in lipid metabolism and metabolic disorders.

  2. Endogenous Magnetic Reconnection in Solar Coronal Loops

    Science.gov (United States)

    Asgari-Targhi, M.; Coppi, B.; Basu, B.; Fletcher, A.; Golub, L.

    2017-12-01

    We propose that a magneto-thermal reconnection process occurring in coronal loops be the source of the heating of the Solar Corona [1]. In the adopted model, magnetic reconnection is associated with electron temperature gradients, anisotropic electron temperature fluctuations and plasma current density gradients [2]. The input parameters for our theoretical model are derived from the most recent observations of the Solar Corona. In addition, the relevant (endogenous) collective modes can produce high energy particle populations. An endogenous reconnection process is defined as being driven by factors internal to the region where reconnection takes place. *Sponsored in part by the U.S. D.O.E. and the Kavli Foundation* [1] Beafume, P., Coppi, B. and Golub, L., (1992) Ap. J. 393, 396. [2] Coppi, B. and Basu, B. (2017) MIT-LNS Report HEP 17/01.

  3. Endogenous opioids encode relative taste preference.

    Science.gov (United States)

    Taha, Sharif A; Norsted, Ebba; Lee, Lillian S; Lang, Penelope D; Lee, Brian S; Woolley, Joshua D; Fields, Howard L

    2006-08-01

    Endogenous opioid signaling contributes to the neural control of food intake. Opioid signaling is thought to regulate palatability, the reward value of a food item as determined by orosensory cues such as taste and texture. The reward value of a food reflects not only these sensory properties but also the relative value of competing food choices. In the present experiment, we used a consummatory contrast paradigm to manipulate the relative value of a sucrose solution for two groups of rats. Systemic injection of the nonspecific opioid antagonist naltrexone suppressed sucrose intake; for both groups, however, this suppression was selective, occurring only for the relatively more valuable sucrose solution. Our results indicate that endogenous opioid signaling contributes to the encoding of relative reward value.

  4. Endogenous Natural Complement Inhibitor Regulates Cardiac Development

    DEFF Research Database (Denmark)

    Mortensen, Simon A; Skov, Louise L; Kjaer-Sorensen, Kasper

    2017-01-01

    mechanisms during fetal development and adult homeostasis. In this article, we describe the function of an endogenous complement inhibitor, mannan-binding lectin (MBL)-associated protein (MAp)44, in regulating the composition of a serine protease-pattern recognition receptor complex, MBL-associated serine...... of MAp44 caused impaired cardiogenesis, lowered heart rate, and decreased cardiac output. These defects were associated with aberrant neural crest cell behavior. We found that MAp44 competed with MASP-3 for pattern recognition molecule interaction, and knockdown of endogenous MAp44 expression could...... be rescued by overexpression of wild-type MAp44. Our observations provide evidence that immune molecules are centrally involved in the orchestration of cardiac tissue development....

  5. Endogeneity of Money Supply: Evidence From Turkey

    Directory of Open Access Journals (Sweden)

    Oguzhan Cepni

    2017-02-01

    Full Text Available There is a long discussion among academics and central bankers about the theories of money supply. According to the exogenous view, central banks have the full control over money supply via policy actions including the adjustments of interest rates and reserve ratios, both of which alter commercial banks’ lending decisions. However, the theory of endogenous money supply emphasizes the role of demand for bank loans in money creation. More specifically, banks create money by meeting the demand of economic agents. In this study, we investigate which of the money supply theories holds in Turkish economy for the period 2006-2015 by employing cointegration and causality tests. Our findings show that the causality runs from bank loans to money supply both in the short and long terms, which supports the endogenous view in a sense that central bank and the banks fully meet the total demand for money in Turkish economy.

  6. Independent effects of endogenous and exogenous attention in touch.

    Science.gov (United States)

    Jones, Alexander; Forster, Bettina

    2013-12-01

    Endogenous and exogenous attention in touch have typically been investigated separately. Here we use a double-cueing paradigm manipulating both types of orienting in each trial. Bilateral endogenous cues induced long-lasting facilitation of endogenous attention up to 2 s. However, the exogenous cue only elicited an effect at short intervals. Our results favour a supramodal account of attention and this study provides new insight into how endogenous and exogenous attention operates in the tactile modality.

  7. Endogenous pyrogen-like substance produced by reptiles.

    Science.gov (United States)

    Bernheim, H A; Kluger, M J

    1977-06-01

    1. Injection of lizards (Dipsosaurus dorsalis) with rabbit endogenous pyrogen led to a fever. Injections with denatured endogenous pyrogen did not affect body temperature. 2. Injection of lizards with lizard endogenous pyrogen led to a fever of short duration, while injection of denatured lizard endogenous pyrogen produced no change in body temperature. 3. These data support the hypothesis that the febrile mechanism observed in the higher vertebrates has its origins in some primitive vertebrate.

  8. Spatial organization of lipids in the human retina and optic nerve by MALDI imaging mass spectrometry.

    Science.gov (United States)

    Zemski Berry, Karin A; Gordon, William C; Murphy, Robert C; Bazan, Nicolas G

    2014-03-01

    MALDI imaging mass spectrometry (IMS) was used to characterize lipid species within sections of human eyes. Common phospholipids that are abundant in most tissues were not highly localized and observed throughout the accessory tissue, optic nerve, and retina. Triacylglycerols were highly localized in accessory tissue, whereas sulfatide and plasmalogen glycerophosphoethanolamine (PE) lipids with a monounsaturated fatty acid were found enriched in the optic nerve. Additionally, several lipids were associated solely with the inner retina, photoreceptors, or retinal pigment epithelium (RPE); a plasmalogen PE lipid containing DHA (22:6), PE(P-18:0/22:6), was present exclusively in the inner retina, and DHA-containing glycerophosphatidylcholine (PC) and PE lipids were found solely in photoreceptors. PC lipids containing very long chain (VLC)-PUFAs were detected in photoreceptors despite their low abundance in the retina. Ceramide lipids and the bis-retinoid, N-retinylidene-N-retinylethanolamine, was tentatively identified and found only in the RPE. This MALDI IMS study readily revealed the location of many lipids that have been associated with degenerative retinal diseases. Complex lipid localization within retinal tissue provides a global view of lipid organization and initial evidence for specific functions in localized regions, offering opportunities to assess their significance in retinal diseases, such as macular degeneration, where lipids have been implicated in the disease process.

  9. LTRs of Endogenous Retroviruses as a Source of Tbx6 Binding Sites.

    Science.gov (United States)

    Yasuhiko, Yukuto; Hirabayashi, Yoko; Ono, Ryuichi

    2017-01-01

    Retrotransposons are abundant in mammalian genomes and can modulate the gene expression of surrounding genes by disrupting endogenous binding sites for transcription factors (TFs) or providing novel TFs binding sites within retrotransposon sequences. Here, we show that a (C/T)CACACCT sequence motif in ORR1A, ORR1B, ORR1C, and ORR1D, Long Terminal Repeats (LTRs) of MaLR endogenous retrovirus (ERV), is the direct target of Tbx6, an evolutionary conserved family of T-box TFs. Moreover, by comparing gene expression between control mice (Tbx6 +/-) and Tbx6-deficient mice (Tbx6 -/-), we demonstrate that at least four genes, Twist2, Pitx2, Oscp1 , and Nfxl1 , are down-regulated with Tbx6 deficiency. These results suggest that ORR1A, ORR1B, ORR1C and ORR1D may contribute to the evolution of mammalian embryogenesis.

  10. A General Theory of Endogenous Market Structures

    OpenAIRE

    Federico Etro; Paolo Bertoletti

    2014-01-01

    We provide a unified approach to imperfect (monopolistic, Bertrand and Cournot) competition equilibria with demand functions derived from symmetric preferences over a large but finite number of goods. The equilibrium markups depend on the Morishima Elasticity of Substitution/Complementarity between goods, and can be derived directly from the utility functions and ranked unambiguously. We characterize the endogenous market structures, their dependence on market size, income and firms’ producti...

  11. Pensions with Heterogenous Individuals and Endogenous Fertility

    OpenAIRE

    Cremer, Helmuth; Gahvari, Firouz; Pestieau, Pierre

    2004-01-01

    This paper studies the design of pension schemes in a society where fertility is endogenous and parents differ in their ability to raise children. In a world with perfect information, a pay-as-you-go social security system is characterized by equal pensions for all but different contributions which may or may not increase with the number of children. Additionally, fertility must be subsidized at the margin to correct for the externality that accompanies fertility. In a world of asymmetric inf...

  12. Endogenous Growth, Monetary Shocks and Nominal Rigidities

    OpenAIRE

    Annicchiarico, Barbara; Pelloni, Alessandra; Lorenza, Rossi

    2010-01-01

    We introduce endogenous growth in an otherwise standard NK model with staggered prices and wages. Some results follow: (i) monetary volatility negatively affects long-run growth; (ii) the relation between nominal volatility and growth depends on the persistence of the nominal shocks and on the Taylor rule considered; (iii) a Taylor rule with smoothing increases the negative effect of nominal volatility on mean growth.

  13. Social Security, Intergenerational Transfers, and Endogenous Growth

    OpenAIRE

    Junsen Zhang; Junxi Zhang

    1998-01-01

    In this paper, the effects of social security in a simple model of endogenous growth with alternative motives of having children are analyzed. It shows how the effects of social security depend on the size of the social security tax, the motive to have children, and the pattern of intergenerational transfers. The pattern of intergenerational transfers itself, however, is shown to change with the social security tax rate. When the social security tax is not too high, social security increases ...

  14. The endogeneity of money and the eurosystem

    OpenAIRE

    Steiger, Otto

    2004-01-01

    The endogenous theory of money, developed by Basil Moore, argues that the supply of central bank money in modern economies is not under the control of the central bank. According to this view, a central bank typically supplies cash reserves automatically on demand at its minimum lending rate, resulting in a clearly horizontal money supply function. While the paper agrees with Moore that the supply of central bank money cannot be determined exogenously by the central bank, it wonders whether t...

  15. Endogeneity of Money Supply: Evidence From Turkey

    OpenAIRE

    Oguzhan Cepni; Ibrahim Ethem Guney

    2017-01-01

    There is a long discussion among academics and central bankers about the theories of money supply. According to the exogenous view, central banks have the full control over money supply via policy actions including the adjustments of interest rates and reserve ratios, both of which alter commercial banks’ lending decisions. However, the theory of endogenous money supply emphasizes the role of demand for bank loans in money creation. More specifically, banks create money by meeting the demand ...

  16. Ciliary neurotrophic factor is an endogenous pyrogen.

    OpenAIRE

    Shapiro, L; Zhang, X X; Rupp, R G; Wolff, S M; Dinarello, C A

    1993-01-01

    Fever is initiated by the action of polypeptide cytokines called endogenous pyrogens, which are produced by the host during inflammation, trauma, or infection and which elevate the thermoregulatory set point in the hypothalamus. Ciliary neurotrophic factor (CNTF) supports the differentiation and survival of central and peripheral neurons. We describe the activity of CNTF as intrinsically pyrogenic in the rabbit. CNTF induced a monophasic fever which rose rapidly (within the first 12 min) foll...

  17. Nitrogen abundance in Comet Halley

    International Nuclear Information System (INIS)

    Wyckoff, S.; Tegler, S.C.; Engel, L.

    1991-01-01

    Data on the nitrogen-containing compounds that observed spectroscopically in the coma of Comet Halley are summarized, and the elemental abundance of nitrogen in the Comet Halley nucleus is derived. It is found that 90 percent of elemental nitrogen is in the dust fraction of the coma, while in the gas fraction, most of the nitrogen is contained in NH3 and CN. The elemental nitrogen abundance in the ice component of the nucleus was found to be deficient by a factor of about 75, relative to the solar photosphere, indicating that the chemical partitioning of N2 into NH3 and other nitrogen compounds during the evolution of the solar nebula cannot account completely for the low abundance ratio N2/NH3 = 0.1, observed in the comet. It is suggested that the low N2/NH3 ratio in Comet Halley may be explained simply by physical fractionation and/or thermal diffusion. 88 refs

  18. Abundances in field dwarf stars. II. Carbon and nitrogen abundances

    Energy Technology Data Exchange (ETDEWEB)

    Laird, J.B.

    1985-02-15

    Intermediate-dispersion spectra of 116 field dwarf stars, plus 10 faint field giants and 3 Hyades dwarfs, have been used to derive carbon and nitrogen abundances relative to iron. The program sample includes both disk and halo stars, spanning a range in (Fe/H) of +0.50 to -2.45. Synthetic spectra of CH and NH bands have been used to determine carbon and nitrogen abundances. The C/Fe ratio is solar over the range of metallicity studied, with an estimated intrinsic scatter of 0.10 dex. Down to (Fe/H)roughly-equal-1.8, below which the nitrogen abundance could not be measured, the N/Fe ratio is also constant for the majority of stars, indicating that nitrogen production is largely primary. Four halo stars are found to be enhanced in nitrogen relative to iron, by factors between 5 and 50, although their carbon abundances appear to be normal. These results are discussed in connection with the chemical evolution of the Galaxy and the sites of C, N, and Fe nucleosynthesis. The results require that C, N, and Fe be produced in stars of similar mass. Our current understanding of N production, then, implies that most Type I supernovae have intermediate-mass progenitors. The nitrogen in the N-enhanced halo stars is very probably primordial, indicating that the interstellar medium at early epochs contained substantial inhomogeneities.

  19. Abundances in field dwarf stars. II. Carbon and nitrogen abundances

    International Nuclear Information System (INIS)

    Laird, J.B.

    1985-01-01

    Intermediate-dispersion spectra of 116 field dwarf stars, plus 10 faint field giants and 3 Hyades dwarfs, have been used to derive carbon and nitrogen abundances relative to iron. The program sample includes both disk and halo stars, spanning a range in [Fe/H] of +0.50 to -2.45. Synthetic spectra of CH and NH bands have been used to determine carbon and nitrogen abundances. The C/Fe ratio is solar over the range of metallicity studied, with an estimated intrinsic scatter of 0.10 dex. Down to [Fe/H]roughly-equal-1.8, below which the nitrogen abundance could not be measured, the N/Fe ratio is also constant for the majority of stars, indicating that nitrogen production is largely primary. Four halo stars are found to be enhanced in nitrogen relative to iron, by factors between 5 and 50, although their carbon abundances appear to be normal. These results are discussed in connection with the chemical evolution of the Galaxy and the sites of C, N, and Fe nucleosynthesis. The results require that C, N, and Fe be produced in stars of similar mass. Our current understanding of N production, then, implies that most Type I supernovae have intermediate-mass progenitors. The nitrogen in the N-enhanced halo stars is very probably primordial, indicating that the interstellar medium at early epochs contained substantial inhomogeneities

  20. CHLORINE ABUNDANCES IN COOL STARS

    Energy Technology Data Exchange (ETDEWEB)

    Maas, Z. G.; Pilachowski, C. A. [Indiana University Bloomington, Astronomy Department, Swain West 319, 727 East Third Street, Bloomington, IN 47405-7105 (United States); Hinkle, K., E-mail: zmaas@indiana.edu, E-mail: cpilacho@indiana.edu, E-mail: hinkle@noao.edu [National Optical Astronomy Observatory, P.O. Box 26732, Tucson, AZ 85726 (United States)

    2016-12-01

    Chlorine abundances are reported in 15 evolved giants and 1 M dwarf in the solar neighborhood. The Cl abundance was measured using the vibration-rotation 1-0 P8 line of H{sup 35}Cl at 3.69851 μ m. The high-resolution L -band spectra were observed using the Phoenix infrared spectrometer on the Kitt Peak Mayall 4 m telescope. The average [{sup 35}Cl/Fe] abundance in stars with −0.72 < [Fe/H] < 0.20 is [{sup 35}Cl/Fe] = (−0.10 ± 0.15) dex. The mean difference between the [{sup 35}Cl/Fe] ratios measured in our stars and chemical evolution model values is (0.16 ± 0.15) dex. The [{sup 35}Cl/Ca] ratio has an offset of ∼0.35 dex above model predictions, suggesting that chemical evolution models are underproducing Cl at the high metallicity range. Abundances of C, N, O, Si, and Ca were also measured in our spectral region and are consistent with F and G dwarfs. The Cl versus O abundances from our sample match Cl abundances measured in planetary nebula and H ii regions. In one star where both H{sup 35}Cl and H{sup 37}Cl could be measured, a {sup 35}Cl/{sup 37}Cl isotope ratio of 2.2 ± 0.4 was found, consistent with values found in the Galactic ISM and predicted chemical evolution models.

  1. Endogenous cueing attenuates object substitution masking.

    Science.gov (United States)

    Germeys, Filip; Pomianowska, I; De Graef, P; Zaenen, P; Verfaillie, K

    2010-07-01

    Object substitution masking (OSM) is a form of visual masking in which a briefly presented target surrounded by four small dots is masked by the continuing presence of the four dots after target offset. A major parameter in the prediction of OSM is the time required for attention to be directed to the target following its onset. Object substitution theory (Di Lollo et al. in J Exp Psychol Gen 129:481-507, 2000) predicts that the sooner attention can be focused at the target's location, the less masking will ensue. However, recently Luiga and Bachmann (Psychol Res 71:634-640, 2007) presented evidence that precueing of attention to the target location prior to target-plus-mask onset by means of a central (endogenous) arrow cue does not reduce OSM. When attention was cued exogenously, OSM was attenuated. Based on these results, Luiga and Bachmann argued that object substitution theory should be adapted by differentiating the ways of directing attention to the target location. The goal of the present study was to further examine the dissociation between the effects of endogenous and exogenous precueing on OSM. Contrary to Luiga and Bachmann, our results show that prior shifts of attention to the target location initiated by both exogenous and endogenous cues reduce OSM as predicted by object substitution theory and its computational model CMOS.

  2. Endogenous growth theory and regional development policy

    Directory of Open Access Journals (Sweden)

    Cvetanović Slobodan

    2015-01-01

    Full Text Available The numerous versions of endogenous explanations of economic growth emphasize the importance of technological change driving forces, as well as the existence of appropriate institutional arrangements. Endogenous growth theory contributes to a better understanding of various experiences with long-term growth of countries and regions. It changes the key assumptions of the Neoclassical growth theory and participates in the modern regional development physiology explanation. Based on these conclusions, the paper: a explicates the most important theoretical postulates of the theory, b explains the most important factors of economic growth in the regions in light of the Endogenous growth theory messages and c emphasizes the key determinants of regional competitiveness which in our view is conceptually between the phenomena of micro- and macro-competitiveness and represents their necessary and unique connection. First of all, micro-competitiveness is transformed into a regional competitiveness; then regional competitiveness is transformed into a macro-competitiveness. In turn, macro - influences the microeconomic competitiveness, and the circle is closed. After that, the process starts over again.

  3. Induced pluripotency with endogenous and inducible genes

    International Nuclear Information System (INIS)

    Duinsbergen, Dirk; Eriksson, Malin; Hoen, Peter A.C. 't; Frisen, Jonas; Mikkers, Harald

    2008-01-01

    The recent discovery that two partly overlapping sets of four genes induce nuclear reprogramming of mouse and even human cells has opened up new possibilities for cell replacement therapies. Although the combination of genes that induce pluripotency differs to some extent, Oct4 and Sox2 appear to be a prerequisite. The introduction of four genes, several of which been linked with cancer, using retroviral approaches is however unlikely to be suitable for future clinical applications. Towards developing a safer reprogramming protocol, we investigated whether cell types that express one of the most critical reprogramming genes endogenously are predisposed to reprogramming. We show here that three of the original four pluripotency transcription factors (Oct4, Klf4 and c-Myc or MYCER TAM ) induced reprogramming of mouse neural stem (NS) cells exploiting endogenous SoxB1 protein levels in these cells. The reprogrammed neural stem cells differentiated into cells of each germ layer in vitro and in vivo, and contributed to mouse development in vivo. Thus a combinatorial approach taking advantage of endogenously expressed genes and inducible transgenes may contribute to the development of improved reprogramming protocols

  4. Endogenous lung regeneration: potential and limitations.

    Science.gov (United States)

    Rock, Jason; Königshoff, Melanie

    2012-12-15

    The exploration of the endogenous regenerative potential of the diseased adult human lung represents an innovative and exciting task. In this pulmonary perspective, we discuss three major components essential for endogenous lung repair and regeneration: epithelial progenitor populations, developmental signaling pathways that regulate their reparative and regenerative potential, and the surrounding extracellular matrix in the human diseased lung. Over the past years, several distinct epithelial progenitor populations have been discovered within the lung, all of which most likely respond to different injuries by varying degrees. It has become evident that several progenitor populations are mutually involved in maintenance and repair, which is highly regulated by developmental pathways, such as Wnt or Notch signaling. Third, endogenous progenitor cells and developmental signaling pathways act in close spatiotemporal synergy with the extracellular matrix. These three components define and refine the highly dynamic microenvironment of the lung, which is altered in a disease-specific fashion in several chronic lung diseases. The search for the right mixture to induce efficient and controlled repair and regeneration of the diseased lung is ongoing and will open completely novel avenues for the treatment of patients with chronic lung disease.

  5. Endogenous viral elements in animal genomes.

    Directory of Open Access Journals (Sweden)

    Aris Katzourakis

    2010-11-01

    Full Text Available Integration into the nuclear genome of germ line cells can lead to vertical inheritance of retroviral genes as host alleles. For other viruses, germ line integration has only rarely been documented. Nonetheless, we identified endogenous viral elements (EVEs derived from ten non-retroviral families by systematic in silico screening of animal genomes, including the first endogenous representatives of double-stranded RNA, reverse-transcribing DNA, and segmented RNA viruses, and the first endogenous DNA viruses in mammalian genomes. Phylogenetic and genomic analysis of EVEs across multiple host species revealed novel information about the origin and evolution of diverse virus groups. Furthermore, several of the elements identified here encode intact open reading frames or are expressed as mRNA. For one element in the primate lineage, we provide statistically robust evidence for exaptation. Our findings establish that genetic material derived from all known viral genome types and replication strategies can enter the animal germ line, greatly broadening the scope of paleovirological studies and indicating a more significant evolutionary role for gene flow from virus to animal genomes than has previously been recognized.

  6. Endogenous leukotriene formation during anaphylactic shock

    International Nuclear Information System (INIS)

    Keppler, A.; Oerning, L.; Bernstroem, K.; Hammarstroem, S.

    1987-01-01

    Leukotriene (LT)C 4 is a biologically active substance, presumed to play major roles as a mediator of allergic and anaphylactic reactions. It is formed e.g. by basophilic and eosinophilic leukocytes, monocytes, macrophages, and mast cells. In cells having IgE receptors, bridging of these by divalent anti-IgE-receptor antibodies or by interaction between receptor-bound IgE and anti-IgE will induce LTC 4 formation. Leukotriene formation has also been demonstrated in other in vitro models of immediate hypersensivity. The biological actions of LTC 4 , comprise induction of airway obstruction, constriction of coronary arteries, hypotension, and plasma extravasation. Leukotriene formation in vivo may mediate anaphylactic shock symptoms and cause the death of an animal. In order to prove the presumed mediator role of this substance in anaphylactic reactions, it is necessary to demonstrate its endogenous formation during shock. Studies on the metabolism of LTC 4 have revealed rapid catabolism by various transformations of the peptide substituent. Recently, three metabolites were demonstrated to be excreted as end-products in man (LTE 4 ,) and the rat (N-acetyl LTE 4 and N-acetyl 11-trans LTE 4 ). By monitoring biliary N-acetyl LTE 4 levels, endogenous leukotriene formation in the rat was demonstrated in vivo after tissue trauma and endotoxin shock. We now wish to report evidence for endogenous leukotriene C 4 production during anaphylactic shock in guinea pigs. 37 refs. (author)

  7. Exercise induced asthma and endogenous opioids.

    Science.gov (United States)

    Gaillard, R C; Bachman, M; Rochat, T; Egger, D; de Haller, R; Junod, A F

    1986-01-01

    Concentrations of endogenous opioid peptides in the plasma are increased during exercise and these substances have been implicated in the pathogenesis of asthma induced by chloropropramide and alcohol in diabetic patients. This work was undertaken to determine whether exercise induced asthma might be mediated by endogenous opioids. Plasma beta endorphin, met-enkephalin, and adrenocorticotrophic hormone (ACTH) concentrations were measured in five asthmatic patients and five normal volunteers breathing cold air during exercise. In four of the patients the effect of an infusion of naloxone on FEV1 was also measured during exercise induced asthma. Exercise produced acute bronchoconstriction in all asthmatics, characterised by a fall in FEV1; whereas no change occurred in normal subjects. There was no difference in plasma met-enkephalin, beta endorphin, and ACTH concentration between the two groups. Infusion of naloxone neither prevented nor worsened exercise induced asthma. These data suggest that endogenous opioids probably do not play a part in the development of exercise induced asthma. PMID:2944240

  8. The search for an endogenous activator.

    Science.gov (United States)

    Gekowski, K. M.; Atkins, E.

    1985-01-01

    Certain febrile diseases are unaccompanied by infection or apparent hypersensitivity. In myocardial infarction or pulmonary embolism, for example, fever has been attributed to inflammation and/or tissue necrosis. Exogenous (microbial) pyrogens stimulate both human and animal monocytes/macrophages to produce endogenous pyrogen (EP) in vitro. To determine if plasma and cellular endogeneous mediators (EMs) of inflammation induced EP production, human mononuclear cells (M/L) were incubated for 18 hours with varying amounts of EM and the supernates assayed for EP in rabbits. Neutrophils (PMNs), which do not generate EP and yet are a feature of acute inflammation, were tested. Neither viable, phorbol myristic acetate-stimulated PMNs nor sonicated PMNs, red blood cells, or M/L stimulated human monocytes to produce EP. Human C3b and C5a, which mediate phagocytosis and chemotaxis, respectively, were also inactive. Despite its chemoattractant properties, the synthetic peptide FMLP failed to induce EP release. Since Poly I:Poly C (PIC: a synthetic, double-stranded RNA) is a potent pyrogen in rabbits, we investigated PIC, as well as a native, single-stranded RNA (from E. coli) and DNA (from calf thymus). None was active in vitro, and only PIC caused fever when given to rabbits intravenously. In summary, we have been unable to find an endogenous activator of EP from human monocytes to explain fevers associated with inflammation alone. PMID:3875936

  9. Avanti lipid tools: connecting lipids, technology, and cell biology.

    Science.gov (United States)

    Sims, Kacee H; Tytler, Ewan M; Tipton, John; Hill, Kasey L; Burgess, Stephen W; Shaw, Walter A

    2014-08-01

    Lipid research is challenging owing to the complexity and diversity of the lipidome. Here we review a set of experimental tools developed for the seasoned lipid researcher, as well as, those who are new to the field of lipid research. Novel tools for probing protein-lipid interactions, applications for lipid binding antibodies, enhanced systems for the cellular delivery of lipids, improved visualization of lipid membranes using gold-labeled lipids, and advances in mass spectrometric analysis techniques will be discussed. Because lipid mediators are known to participate in a host of signal transduction and trafficking pathways within the cell, a comprehensive lipid toolbox that aids the science of lipidomics research is essential to better understand the molecular mechanisms of interactions between cellular components. This article is part of a Special Issue entitled Tools to study lipid functions. Copyright © 2014. Published by Elsevier B.V.

  10. Lipid containing nanodrug delivery system for the treatment of Tuberculosis

    CSIR Research Space (South Africa)

    Lemmer, Yolandy

    2010-09-01

    Full Text Available of the antibiotics in the cells, hence reducing the dose frequency and simultaneously improve patient compliance. The cell wall envelope of Mycobacterium tuberculosis (M.tb) contains unique high molecular weight lipids. Of these, the most abundant are mycolic acids...

  11. Apolipoprotein E promotes lipid accumulation and differentiation in human adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lasrich, Dorothee; Bartelt, Alexander [Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Grewal, Thomas, E-mail: thomas.grewal@sydney.edu.au [Faculty of Pharmacy A15, The University of Sydney, Sydney, NSW 2006 (Australia); Heeren, Joerg, E-mail: heeren@uke.de [Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

    2015-09-10

    Several studies in mice indicate a role for apolipoprotein E (APOE) in lipid accumulation and adipogenic differentiation in adipose tissue. However, little is yet known if APOE functions in a similar manner in human adipocytes. This prompted us to compare lipid loading and expression of adipocyte differentiation markers in APOE-deficient and control adipocytes using the differentiated human mesenchymal stem cell line hMSC-Tert as well as primary human and mouse adipocytes as model systems. Differentiated hMSC-Tert were stably transduced with or without siRNA targeting APOE while murine adipocytes were isolated from wild type and Apoe knockout mice. Human APOE knockdown hMSC-Tert adipocytes accumulated markedly less triglycerides compared to control cells. This correlated with strongly decreased gene expression levels of adipocyte markers such as adiponectin (ADIPOQ) and fatty acid binding protein 4 (FABP4) as well as the key transcription factor driving adipocyte differentiation, peroxisome proliferator activator receptor gamma (PPARG), in particular the PPARG2 isoform. Similarly, differentiation of murine Apoe-deficient adipocytes was characterized by reduced gene expression of Adipoq, Fabp4 and Pparg. Interestingly, incubation of APOE-deficient hMSC-Tert adipocytes with conditioned media from APOE3-overexpressing adipocytes or APOE-containing Very Low Density Lipoprotein (VLDL) partially restored triglyceride accumulation, but were unable to induce adipocyte differentiation, as judged by expression of adipocyte markers. Taken together, depletion of endogenous APOE in human adipocytes severely impairs lipid accumulation, which is associated with an inability to initiate differentiation. - Highlights: • Immortalized human mesenchymal stem cells were used to study adipocyte development. • Knockdown of endogenous APOE lead to impaired lipid accumulation and adipogenesis. • APOE supplementation partially restored lipid accumulation but not differentiation.

  12. Synthesis of Lipidated Proteins.

    Science.gov (United States)

    Mejuch, Tom; Waldmann, Herbert

    2016-08-17

    Protein lipidation is one of the major post-translational modifications (PTM) of proteins. The attachment of the lipid moiety frequently determines the localization and the function of the lipoproteins. Lipidated proteins participate in many essential biological processes in eukaryotic cells, including vesicular trafficking, signal transduction, and regulation of the immune response. Malfunction of these cellular processes usually leads to various diseases such as cancer. Understanding the mechanism of cellular signaling and identifying the protein-protein and protein-lipid interactions in which the lipoproteins are involved is a crucial task. To achieve these goals, fully functional lipidated proteins are required. However, access to lipoproteins by means of standard expression is often rather limited. Therefore, semisynthetic methods, involving the synthesis of lipidated peptides and their subsequent chemoselective ligation to yield full-length lipoproteins, were developed. In this Review we summarize the commonly used methods for lipoprotein synthesis and the development of the corresponding chemoselective ligation techniques. Several key studies involving full-length semisynthetic lipidated Ras, Rheb, and LC3 proteins are presented.

  13. Perspectives on marine zooplankton lipids

    DEFF Research Database (Denmark)

    Kattner, G.; Hagen, W.; Lee, R.F.

    2007-01-01

    We developed new perspectives to identify important questions and to propose approaches for future research on marine food web lipids. They were related to (i) structure and function of lipids, (ii) lipid changes during critical life phases, (iii) trophic marker lipids, and (iv) potential impact...... of climate change. The first addresses the role of lipids in membranes, storage lipids, and buoyancy with the following key question: How are the properties of membranes and deposits affected by the various types of lipids? The second deals with the importance of various types of lipids during reproduction......, development, and resting phases and addresses the role of the different storage lipids during growth and dormancy. The third relates to trophic marker lipids, which are an important tool to follow lipid and energy transfer through the food web. The central question is how can fatty acids be used to identify...

  14. Chinook Abundance - Point Features [ds180

    Data.gov (United States)

    California Natural Resource Agency — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  15. Steelhead Abundance - Linear Features [ds185

    Data.gov (United States)

    California Natural Resource Agency — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  16. Steelhead Abundance - Point Features [ds184

    Data.gov (United States)

    California Natural Resource Agency — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  17. Coho Abundance - Linear Features [ds183

    Data.gov (United States)

    California Natural Resource Agency — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  18. Coho Abundance - Point Features [ds182

    Data.gov (United States)

    California Natural Resource Agency — The CalFish Abundance Database contains a comprehensive collection of anadromous fisheries abundance information. Beginning in 1998, the Pacific States Marine...

  19. Estimation of the endogenous N proportions in ileal digesta and faeces in 15N-labelled pigs

    International Nuclear Information System (INIS)

    Simon, O.; Bergner, H.

    1987-01-01

    4 castrated male pigs 40 kg fitted with simple 'T' cannulas in the terminal ileum were given 15 N-labelled ammonium salts, added to a low protein diet, for 6 days. Excretion of 15 N in urine and feces was monitored daily throughout the labelling and subsequent experimental periods. During the experimental period the pigs were given a diet based on wheat and fish meal, supplemented with varying levels of partially hydrolyzed straw meal to give crude fiber contents ranging from 40 to 132 g/kg. After adaptation to the particular levels of straw meal, feces and ileal digesta were collected during successive 24 h periods. N digestibility values were determined by the chromium oxide ratio method. The retention of 15 N-labelled non-specific N was 0.46 of the dose given. The validity of using urine values as a measure of 15 N abundance in endogenous N was demonstrated by the similarity of 15 N abundance in urine immediately before slaughter at the end of the experiment and in the digestive secretory organs thereafter. The average amount of endogenous N passing the terminal ileum was 3.4 g/day or 0.30-0.50 of total ileal N flow. This was not affected by dietary fiber level. The proportion of fecal N which was of endogenous origin was similar to that in ileal digesta, suggesting similar utilization of endogenous and residual dietary N by hindgut bacteria. Half the endogenous N entering the large intestine was reabsorbed there. Increasing dietary crude fiber from 40 to 132 g/kg increased fecal endogenous N excretion from 1.3 to 2.0 g/animal and day. (author)

  20. Abundance estimation and conservation biology

    Science.gov (United States)

    Nichols, J.D.; MacKenzie, D.I.

    2004-01-01

    Abundance is the state variable of interest in most population–level ecological research and in most programs involving management and conservation of animal populations. Abundance is the single parameter of interest in capture–recapture models for closed populations (e.g., Darroch, 1958; Otis et al., 1978; Chao, 2001). The initial capture–recapture models developed for partially (Darroch, 1959) and completely (Jolly, 1965; Seber, 1965) open populations represented efforts to relax the restrictive assumption of population closure for the purpose of estimating abundance. Subsequent emphases in capture–recapture work were on survival rate estimation in the 1970’s and 1980’s (e.g., Burnham et al., 1987; Lebreton et al.,1992), and on movement estimation in the 1990’s (Brownie et al., 1993; Schwarz et al., 1993). However, from the mid–1990’s until the present time, capture–recapture investigators have expressed a renewed interest in abundance and related parameters (Pradel, 1996; Schwarz & Arnason, 1996; Schwarz, 2001). The focus of this session was abundance, and presentations covered topics ranging from estimation of abundance and rate of change in abundance, to inferences about the demographic processes underlying changes in abundance, to occupancy as a surrogate of abundance. The plenary paper by Link & Barker (2004) is provocative and very interesting, and it contains a number of important messages and suggestions. Link & Barker (2004) emphasize that the increasing complexity of capture–recapture models has resulted in large numbers of parameters and that a challenge to ecologists is to extract ecological signals from this complexity. They offer hierarchical models as a natural approach to inference in which traditional parameters are viewed as realizations of stochastic processes. These processes are governed by hyperparameters, and the inferential approach focuses on these hyperparameters. Link & Barker (2004) also suggest that our attention

  1. Abundance estimation and Conservation Biology

    Directory of Open Access Journals (Sweden)

    Nichols, J. D.

    2004-06-01

    Full Text Available Abundance is the state variable of interest in most population–level ecological research and in most programs involving management and conservation of animal populations. Abundance is the single parameter of interest in capture–recapture models for closed populations (e.g., Darroch, 1958; Otis et al., 1978; Chao, 2001. The initial capture–recapture models developed for partially (Darroch, 1959 and completely (Jolly, 1965; Seber, 1965 open populations represented efforts to relax the restrictive assumption of population closure for the purpose of estimating abundance. Subsequent emphases in capture–recapture work were on survival rate estimation in the 1970’s and 1980’s (e.g., Burnham et al., 1987; Lebreton et al.,1992, and on movement estimation in the 1990’s (Brownie et al., 1993; Schwarz et al., 1993. However, from the mid–1990’s until the present time, capture–recapture investigators have expressed a renewed interest in abundance and related parameters (Pradel, 1996; Schwarz & Arnason, 1996; Schwarz, 2001. The focus of this session was abundance, and presentations covered topics ranging from estimation of abundance and rate of change in abundance, to inferences about the demographic processes underlying changes in abundance, to occupancy as a surrogate of abundance. The plenary paper by Link & Barker (2004 is provocative and very interesting, and it contains a number of important messages and suggestions. Link & Barker (2004 emphasize that the increasing complexity of capture–recapture models has resulted in large numbers of parameters and that a challenge to ecologists is to extract ecological signals from this complexity. They offer hierarchical models as a natural approach to inference in which traditional parameters are viewed as realizations of stochastic processes. These processes are governed by hyperparameters, and the inferential approach focuses on these hyperparameters. Link & Barker (2004 also suggest that

  2. Archaeal and bacterial H-GDGTs are abundant in peat and their relative abundance is positively correlated with temperature

    Science.gov (United States)

    Naafs, B. D. A.; McCormick, D.; Inglis, G. N.; Pancost, R. D.; T-GRES Peat Database Collaborators

    2018-04-01

    Glycerol monoalkyl glycerol tetraether lipids (GMGTs; also called 'H-GDGTs') differ from the more commonly studied glycerol dialkyl glycerol tetraether (GDGTs) in that they have an additional covalent bond that links the two alkyl chains. Six different archaeal isoprenoidal H-GDGTs (H-isoGDGTs) and one branched H-GDGT (H-brGDGT), presumably produced by bacteria, have previously been found. However, the function of H-GDGTs in both domains of life is unknown. It is thought that the formation of this additional covalent bond results in enhanced membrane stability, accounting for the high abundance of H-GDGTs in extreme environments such as geothermal settings, but so far there has been little evidence to support this hypothesis. Here we report the distribution of H-GDGTs in a global peat database (n = 471) with a broad range in mean annual air temperature (MAAT) and pH. This is the first finding of H-GDGTs in soils (specifically, peat), highlighting that H-GDGTs are widespread in mesophilic settings. In addition, we report the presence of two new H-brGDGTs with one (H-1034) and two (H-1048) additional methyl groups, respectively. Our results suggest that the relative abundance of both bacterial and archaeal H-GDGTs compared to regular GDGTs is related to temperature with the highest relative abundance of H-GDGTs in tropical peats. Although other factors besides temperature likely also play a role, these results do support the hypothesis that H-GDGTs are an adaptation to temperature to maintain membrane stability. The observation that both bacterial and archaeal membrane lipids respond to temperature indicates the same adaption across the lipid divide between these two domains of life, suggesting parallel or convergent evolution (potentially facilitated by lateral gene transfer).

  3. CD1a presentation of endogenous antigens by group 2 innate lymphoid cells.

    Science.gov (United States)

    Hardman, Clare S; Chen, Yi-Ling; Salimi, Maryam; Jarrett, Rachael; Johnson, David; Järvinen, Valtteri J; Owens, Raymond J; Repapi, Emmanouela; Cousins, David J; Barlow, Jillian L; McKenzie, Andrew N J; Ogg, Graham

    2017-12-22

    Group 2 innate lymphoid cells (ILC2) are effectors of barrier immunity, with roles in infection, wound healing, and allergy. A proportion of ILC2 express MHCII (major histocompatibility complex II) and are capable of presenting peptide antigens to T cells and amplifying the subsequent adaptive immune response. Recent studies have highlighted the importance of CD1a-reactive T cells in allergy and infection, activated by the presentation of endogenous neolipid antigens and bacterial components. Using a human skin challenge model, we unexpectedly show that human skin-derived ILC2 can express CD1a and are capable of presenting endogenous antigens to T cells. CD1a expression is up-regulated by TSLP (thymic stromal lymphopoietin) at levels observed in the skin of patients with atopic dermatitis, and the response is dependent on PLA2G4A. Furthermore, this pathway is used to sense Staphylococcus aureus by promoting Toll-like receptor-dependent CD1a-reactive T cell responses to endogenous ligands. These findings define a previously unrecognized role for ILC2 in lipid surveillance and identify shared pathways of CD1a- and PLA2G4A-dependent ILC2 inflammation amenable to therapeutic intervention. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  4. On the origins of the universal dynamics of endogenous granules in mammalian cells.

    Science.gov (United States)

    Vanapalli, Siva A; Li, Yixuan; Mugele, Frieder; Duits, Michel H G

    2009-12-01

    Endogenous granules (EGs) that consist of lipid droplets and mitochondria have been commonly used to assess intracellular mechanical properties via multiple particle tracking microrheology (MPTM). Despite their widespread use, the nature of interaction of EGs with the cytoskeletal network and the type of forces driving their dynamics--both of which are crucial for the interpretation of the results from MPTM technique--are yet to be resolved. In this report, we study the dynamics of endogenous granules in mammalian cells using particle tracking methods. We find that the ensemble dynamics of EGs is diffusive in three types of mammalian cells (endothelial cells, smooth muscle cells and fibroblasts), thereby suggesting an apparent universality in their dynamical behavior. Moreover, in a given cell, the amplitude of the mean-squared displacement for EGs is an order of magnitude larger than that of injected particles. This observation along with results from ATP depletion and temperature intervention studies suggests that cytoskeletal active forces drive the dynamics of EGs. To elucidate the dynamical origin of the diffusive-like nonthermal motion, we consider three active force generation mechanisms--molecular motor transport, actomyosin contractility and microtubule polymerization forces. We test these mechanisms using pharmacological interventions. Experimental evidence and model calculations suggest that EGs are intimately linked to microtubules and that microtubule polymerization forces drive their dynamics. Thus, endogenous granules could serve as non-invasive probes for microtubule network dynamics in mammalian cells.

  5. Acyl-Lipid Metabolism

    Science.gov (United States)

    Li-Beisson, Yonghua; Shorrosh, Basil; Beisson, Fred; Andersson, Mats X.; Arondel, Vincent; Bates, Philip D.; Baud, Sébastien; Bird, David; DeBono, Allan; Durrett, Timothy P.; Franke, Rochus B.; Graham, Ian A.; Katayama, Kenta; Kelly, Amélie A.; Larson, Tony; Markham, Jonathan E.; Miquel, Martine; Molina, Isabel; Nishida, Ikuo; Rowland, Owen; Samuels, Lacey; Schmid, Katherine M.; Wada, Hajime; Welti, Ruth; Xu, Changcheng; Zallot, Rémi; Ohlrogge, John

    2013-01-01

    Acyl lipids in Arabidopsis and all other plants have a myriad of diverse functions. These include providing the core diffusion barrier of the membranes that separates cells and subcellular organelles. This function alone involves more than 10 membrane lipid classes, including the phospholipids, galactolipids, and sphingolipids, and within each class the variations in acyl chain composition expand the number of structures to several hundred possible molecular species. Acyl lipids in the form of triacylglycerol account for 35% of the weight of Arabidopsis seeds and represent their major form of carbon and energy storage. A layer of cutin and cuticular waxes that restricts the loss of water and provides protection from invasions by pathogens and other stresses covers the entire aerial surface of Arabidopsis. Similar functions are provided by suberin and its associated waxes that are localized in roots, seed coats, and abscission zones and are produced in response to wounding. This chapter focuses on the metabolic pathways that are associated with the biosynthesis and degradation of the acyl lipids mentioned above. These pathways, enzymes, and genes are also presented in detail in an associated website (ARALIP: http://aralip.plantbiology.msu.edu/). Protocols and methods used for analysis of Arabidopsis lipids are provided. Finally, a detailed summary of the composition of Arabidopsis lipids is provided in three figures and 15 tables. PMID:23505340

  6. Enzyme Activities in Oleaginous Yeasts Accumulating and Utilizing Exogenous or Endogenous Lipids

    NARCIS (Netherlands)

    Holdsworth, Jane E.; Veenhuis, Marten; Ratledge, Colin

    1988-01-01

    The activities of ATP:citrate lyase (ACL; EC 4.1.3.8), carnitine acetyltransferase (CAT; EC 2.3.1.7), NADP+-dependent isocitrate dehydrogenase (ICDH; EC 1.1.1.42), isocitrate lyase (ICL; EC 4.1.3.1) and malic enzyme (malate dehydrogenase; EC 1.1.1.40) were measured in four oleaginous yeasts, Candida

  7. Endogenous ω-3 polyunsaturated fatty acid production confers resistance to obesity, dyslipidemia, and diabetes in mice.

    Science.gov (United States)

    Li, Jie; Li, Fanghong R; Wei, Dong; Jia, Wei; Kang, Jing X; Stefanovic-Racic, Maja; Dai, Yifan; Zhao, Allan Z

    2014-08-01

    Despite the well-documented health benefits of ω-3 polyunsaturated fatty acids (PUFAs), their use in clinical management of hyperglycemia and obesity has shown little success. To better define the mechanisms of ω-3 PUFAs in regulating energy balance and insulin sensitivity, we deployed a transgenic mouse model capable of endogenously producing ω-3 PUFAs while reducing ω-6 PUFAs owing to the expression of a Caenorhabditis elegans fat-1 gene encoding an ω-3 fatty acid desaturase. When challenged with high-fat diets, fat-1 mice strongly resisted obesity, diabetes, hypercholesterolemia, and hepatic steatosis. Endogenous elevation of ω-3 PUFAs and reduction of ω-6 PUFAs did not alter the amount of food intake but led to increased energy expenditure in the fat-1 mice. The requirements for the levels of ω-3 PUFAs as well as the ω-6/ω-3 ratios in controlling blood glucose and obesity are much more stringent than those in lipid metabolism. These metabolic phenotypes were accompanied by attenuation of the inflammatory state because tissue levels of prostaglandin E2, leukotriene B4, monocyte chemoattractant protein-1, and TNF-α were significantly decreased. TNF-α-induced nuclear factor-κB signaling was almost completely abolished. Consistent with the reduction in chronic inflammation and a significant increase in peroxisome proliferator-activated receptor-γ activity in the fat-1 liver tissue, hepatic insulin signaling was sharply elevated. The activities of prolipogenic regulators, such as liver X receptor, stearoyl-CoA desaturase-1, and sterol regulatory element binding protein-1 were sharply decreased, whereas the activity of peroxisome proliferator-activated receptor-α, a nuclear receptor that facilitates lipid β-oxidation, was markedly increased. Thus, endogenous conversion of ω-6 to ω-3 PUFAs via fat-1 strongly protects against obesity, diabetes, inflammation, and dyslipidemia and may represent a novel therapeutic modality to treat these prevalent

  8. Use of proton-enhanced, natural abundance /sup 13/C NMR to study the molecular dynamics of model and biological membranes

    Energy Technology Data Exchange (ETDEWEB)

    Cornell, B A [Commonwealth Scientific and Industrial Research Organization, North Ryde (Australia). Div. of Food Research; Keniry, M [Sydney Univ. (Australia). Dept. of Physical Chemistry; Hiller, R G [Macquarie Univ., North Ryde (Australia). School of Biological Sciences; Smith, R [La Trobe Univ., Bundoora (Australia). Dept. of Biochemistry

    1980-06-16

    Proton-enhanced NMR of the natural abundance /sup 13/C nuclei is used to study the lipid mobility in dispersions containing cholesterol, the polypeptide gramicidin A, and in membrane proparations derived from spinach chloroplasts and bovine brain myelin.

  9. Environmental policy, pollution, unemployment and endogenous growth

    DEFF Research Database (Denmark)

    Pedersen, Lars Haagen; Nielsen, Søren Bo; Sørensen, Peter Birch

    1995-01-01

    The paper develops a model of endogenous economic growth with pollution externalities and a labor market distorted by union monopoly power and by taxes and transfers. We study the optimal second-best pollution tax and abatement policy and find that a shift toward greener preferences will tend...... to reduce unemployment, although it will hamper growth. We also find that greater labor-market distortions call for higher pollution tax rates. Finally, we show that a switch from quantity control of pollution combined with grandfathering of pollution rights to regulation via emission charges has...

  10. Optimal pollution taxes and endogenous technological progress

    International Nuclear Information System (INIS)

    Parry, I.W.H.

    1995-01-01

    The optimal pollution tax becomes complicated when allowance is made for endogenous innovation, under a patent system. However, if anything, it is below marginal environmental damages, to counteract monopoly pricing by the patent holder, the common pool effect associated with research and a possible excess of patent holder revenue over the social benefits from innovation when environmental damages are convex. In cases where patents are weak at securing appropriability, for example when rivals can easily imitate around patented technologies, awarding research prizes or contracts is probably more efficient than raising the pollution tax. 24 refs., 4 figs

  11. Diverging patterns with endogenous labor migration.

    Science.gov (United States)

    Reichlin, P; Rustichini, A

    1998-05-05

    "The standard neoclassical model cannot explain persistent migration flows and lack of cross-country convergence when capital and labor are mobile. Here we present a model where both phenomena may take place.... Our model is based on the Arrow-Romer approach to endogenous growth theory. We single out the importance of a (however weak) scale effect from the size of the workforce.... The main conclusion of this simple model is that lack of convergence, or even divergence, among countries is possible, even with perfect capital mobility and labor mobility." excerpt

  12. Endogenous population growth may imply chaos.

    Science.gov (United States)

    Prskawetz, A; Feichtinger, G

    1995-01-01

    The authors consider a discrete-time neoclassical growth model with an endogenous rate of population growth. The resulting one-dimensional map for the capital intensity has a tilted z-shape. Using the theory of nonlinear dynamical systems, they obtain numerical results on the qualitative behavior of time paths for changing parameter values. Besides stable and periodic solutions, erratic time paths may result. In particular, myopic and far-sighted economies--assumed to be characterized by low and high savings rate respectively--are characterized by stable per capita capital stocks, while solutions with chaotic windows exist between these two extremes.

  13. Psychological rehabilitation of patients with endogenous disease

    Directory of Open Access Journals (Sweden)

    Tamara Kryvonis

    2013-07-01

    Full Text Available The rationale for early psychotherapeutic intervention in combination with psychopharmatherapy in patients with endogenous disorders is provided. The mechanisms of psychological defenses to deal with traumatic experience, used by personalities functioning on a psychotic level, are also described here. Characteristic behavior patterns of extended family members in terms of emotional codependence are provided. Individual pathopsychology is considered as a symptom of abnormal functioning of the family. Emphasis is placed on the importance of inclusion of family members in psychotherapeutic interaction in order to correct interpersonal relations.

  14. Endogenous Turnover of Cyanogenic Glycosides in Plants

    DEFF Research Database (Denmark)

    Picmanova, Martina

    , there is strong evidence that CNglcs serve a no less significant purpose as a transport and storage form of reduced nitrogen which may be remobilized and recycled to balance the needs of primary metabolism during certain developmental events. Reduced nitrogen from CNglcs may be recovered either via HCN refixation...... revealed the formation of glycosides of amides, carboxylic acids and "anitriles", including their di- and triglycosides, evidently derived from CNglcs. Based on results common to the three phylogenetically unrelated plant species, a recycling endogenous turnover pathway for CNglcs was suggested in which...

  15. Maintenance, endogeneous, respiration, lysis, decay and predation

    DEFF Research Database (Denmark)

    loosdrecht, Marc C. M. Van; Henze, Mogens

    1999-01-01

    mechanism is microbiologically correct. The lysis/decay model mechanism is a strongly simplified representation of reality. This paper tries to review the processes grouped under endogenous respiration in activated sludge models. Mechanisms and processes such as maintenance, lysis, internal and external...... decay, predation and death-regeneration are discussed. From recent microbial research it has become evident that cells do not die by themselves. Bacteria are however subject to predation by protozoa. Bacteria store reserve polymers that in absence of external substrate are used for growth...

  16. [Formation of endogenous pyrogen by mononuclear phagocytes].

    Science.gov (United States)

    Agasarov, L G

    1980-03-01

    Incubation of alveolar macrophages of rabbits and peritoneal macrophages of the abdominal cavity washing of albino mice does not lead to endogenous pyrogen release. Peritoneal macrophages obtained after peritoneal administration to mice of thioglycollate, glycogen or heterologous blood cells do not discharge pyrogen either during incubation without additional stimulation. Macrophages isolated after intraperitoneal administration of heterologous blood cells do not exhibit pyrogenic activity possibly because of a long period of time elapsed after phagocytosis of foreign agents. The triggering of pyrogen formation by macrophages can be effected by means of in vitro phagocytosis of corpuscular particles: staphylococci or heterologous blood cells.

  17. Attenuated lipotoxicity and apoptosis is linked to exogenous and endogenous augmenter of liver regeneration by different pathways.

    Science.gov (United States)

    Weiss, Thomas S; Lupke, Madeleine; Ibrahim, Sara; Buechler, Christa; Lorenz, Julia; Ruemmele, Petra; Hofmann, Ute; Melter, Michael; Dayoub, Rania

    2017-01-01

    Nonalcoholic fatty liver disease (NAFLD) covers a spectrum from simple steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis. Free fatty acids (FFA) induce steatosis and lipo-toxicity and correlate with severity of NAFLD. In this study we aimed to investigate the role of exogenous and endogenous ALR (augmenter of liver regeneration) for FFA induced ER (endoplasmatic reticulum) -stress and lipoapoptosis. Primary human hepatocytes or hepatoma cells either treated with recombinant human ALR (rhALR, 15kDa) or expressing short form ALR (sfALR, 15kDa) were incubated with palmitic acid (PA) and analyzed for lipo-toxicity, -apoptosis, activation of ER-stress response pathways, triacylglycerides (TAG), mRNA and protein expression of lipid metabolizing genes. Both, exogenous rhALR and cytosolic sfALR reduced PA induced caspase 3 activity and Bax protein expression and therefore lipotoxicity. Endogenous sfALR but not rhALR treatment lowered TAG levels, diminished activation of ER-stress mediators C-Jun N-terminal kinase (JNK), X-box binding protein-1 (XBP1) and proapoptotic transcription factor C/EBP-homologous protein (CHOP), and reduced death receptor 5 protein expression. Cellular ALR exerts its lipid lowering and anti-apoptotic actions by enhancing FABP1, which binds toxic FFA, increasing mitochondrial β-oxidation by elevating the mitochondrial FFA transporter CPT1α, and decreasing ELOVL6, which delivers toxic FFA metabolites. We found reduced hepatic mRNA levels of ALR in a high fat diet mouse model, and of ALR and FOXA2, a transcription factor inducing ALR expression, in human steatotic as well as NASH liver samples, which may explain increased lipid deposition and reduced β-oxidation in NASH patients. Present study shows that exogenous and endogenous ALR reduce PA induced lipoapoptosis. Furthermore, cytosolic sfALR changes mRNA and protein expression of genes regulating lipid metabolism, reduces ER-stress finally impeding progression of NASH.

  18. Attenuated lipotoxicity and apoptosis is linked to exogenous and endogenous augmenter of liver regeneration by different pathways.

    Directory of Open Access Journals (Sweden)

    Thomas S Weiss

    Full Text Available Nonalcoholic fatty liver disease (NAFLD covers a spectrum from simple steatosis to nonalcoholic steatohepatitis (NASH and cirrhosis. Free fatty acids (FFA induce steatosis and lipo-toxicity and correlate with severity of NAFLD. In this study we aimed to investigate the role of exogenous and endogenous ALR (augmenter of liver regeneration for FFA induced ER (endoplasmatic reticulum -stress and lipoapoptosis. Primary human hepatocytes or hepatoma cells either treated with recombinant human ALR (rhALR, 15kDa or expressing short form ALR (sfALR, 15kDa were incubated with palmitic acid (PA and analyzed for lipo-toxicity, -apoptosis, activation of ER-stress response pathways, triacylglycerides (TAG, mRNA and protein expression of lipid metabolizing genes. Both, exogenous rhALR and cytosolic sfALR reduced PA induced caspase 3 activity and Bax protein expression and therefore lipotoxicity. Endogenous sfALR but not rhALR treatment lowered TAG levels, diminished activation of ER-stress mediators C-Jun N-terminal kinase (JNK, X-box binding protein-1 (XBP1 and proapoptotic transcription factor C/EBP-homologous protein (CHOP, and reduced death receptor 5 protein expression. Cellular ALR exerts its lipid lowering and anti-apoptotic actions by enhancing FABP1, which binds toxic FFA, increasing mitochondrial β-oxidation by elevating the mitochondrial FFA transporter CPT1α, and decreasing ELOVL6, which delivers toxic FFA metabolites. We found reduced hepatic mRNA levels of ALR in a high fat diet mouse model, and of ALR and FOXA2, a transcription factor inducing ALR expression, in human steatotic as well as NASH liver samples, which may explain increased lipid deposition and reduced β-oxidation in NASH patients. Present study shows that exogenous and endogenous ALR reduce PA induced lipoapoptosis. Furthermore, cytosolic sfALR changes mRNA and protein expression of genes regulating lipid metabolism, reduces ER-stress finally impeding progression of NASH.

  19. Factors influencing particulate lipid production in the East Atlantic Ocean

    Science.gov (United States)

    Gašparović, B.; Frka, S.; Koch, B. P.; Zhu, Z. Y.; Bracher, A.; Lechtenfeld, O. J.; Neogi, S. B.; Lara, R. J.; Kattner, G.

    2014-07-01

    Extensive analyses of particulate lipids and lipid classes were conducted to gain insight into lipid production and related factors along the biogeochemical provinces of the Eastern Atlantic Ocean. Data are supported by particulate organic carbon (POC), chlorophyll a (Chl a), phaeopigments, Chl a concentrations and carbon content of eukaryotic micro-, nano- and picophytoplankton, including cell abundances for the latter two and for cyanobacteria and prokaryotic heterotrophs. We focused on the productive ocean surface (2 m depth and deep Chl a maximum (DCM). Samples from the deep ocean provided information about the relative reactivity and preservation potential of particular lipid classes. Surface and DCM particulate lipid concentrations (3.5-29.4 μg L-1) were higher than in samples from deep waters (3.2-9.3 μg L-1) where an increased contribution to the POC pool was observed. The highest lipid concentrations were measured in high latitude temperate waters and in the North Atlantic Tropical Gyral Province (13-25°N). Factors responsible for the enhanced lipid synthesis in the eastern Atlantic appeared to be phytoplankton size (micro, nano, pico) and the low nutrient status with microphytoplankton having the most expressed influence in the surface and eukaryotic nano- and picophytoplankton in the DCM layer. Higher lipid to Chl a ratios suggest enhanced lipid biosynthesis in the nutrient poorer regions. The various lipid classes pointed to possible mechanisms of phytoplankton adaptation to the nutritional conditions. Thus, it is likely that adaptation comprises the replacement of membrane phospholipids by non-phosphorus containing glycolipids under low phosphorus conditions. The qualitative and quantitative lipid compositions revealed that phospholipids were the most degradable lipids, and their occurrence decreased with increasing depth. In contrast, wax esters, possibly originating from zooplankton, survived downward transport probably due to the fast sinking

  20. Synthesis of lipid mediators during UVB-induced inflammatory hyperalgesia in rats and mice.

    Directory of Open Access Journals (Sweden)

    Marco Sisignano

    Full Text Available Peripheral sensitization during inflammatory pain is mediated by a variety of endogenous proalgesic mediators including a number of oxidized lipids, some of which serve endogenous modulators of sensory TRP-channels. These lipids are eicosanoids of the arachidonic acid and linoleic acid pathway, as well as lysophophatidic acids (LPAs. However, their regulation pattern during inflammatory pain and their contribution to peripheral sensitization is still unclear. Here, we used the UVB-model for inflammatory pain to investigate alterations of lipid concentrations at the site of inflammation, the dorsal root ganglia (DRGs as well as the spinal dorsal horn and quantified 21 lipid species from five different lipid families at the peak of inflammation 48 hours post irradiation. We found that known proinflammatory lipids as well as lipids with unknown roles in inflammatory pain to be strongly increased in the skin, whereas surprisingly little changes of lipid levels were seen in DRGs or the dorsal horn. Importantly, although there are profound differences between the number of cytochrome (CYP genes between mice and rats, CYP-derived lipids were regulated similarly in both species. Since TRPV1 agonists such as LPA 18∶1, 9- and 13-HODE, 5- and 12-HETE were elevated in the skin, they may contribute to thermal hyperalgesia and mechanical allodynia during UVB-induced inflammatory pain. These results may explain why some studies show relatively weak analgesic effects of cyclooxygenase inhibitors in UVB-induced skin inflammation, as they do not inhibit synthesis of other proalgesic lipids such as LPA 18∶1, 9-and 13-HODE and HETEs.

  1. Study on the influence of lipid peak to the results of MR spectroscopy in the central gland of prostate

    International Nuclear Information System (INIS)

    Dong Yanjun; Wang Xiaoying; Li Feiyu; Jiang Xuexiang

    2007-01-01

    Objective: To study the influence of lipid peak to MRS in central gland of prostate gland. Methods: Seventeen patients performed transurethral resection of prostate (TURP) for benign prostate hyperplasia (BPH) were enrolled in this study. Three groups were divided according to the pathological findings: glandular-BPH (GBPH) (7 cases), stromal-BPH (SBPH) (6 cases), and incidentally detected prostate carcinoma (IDPC) (4 cases). The voxel with lipid peak in the field of volume was counted. Compared with pathology, the following studies were performed: (1) The location of the voxels that more frequently presented lipid peak in the central gland. (2) Whether the appearance of the lipid peak would obscure the identification of the peaks of the endogenous metabolites. Results: The ratio of voxels with lipid peak in central gland was about 22.8% (834/3567). There were 1477 (397 voxels with lipid peak), 1434(396 voxels with lipid peak), and 656(41 voxels with lipid peak) voxels in CBPH, SBPH, and IDPC groups, respectively. The percentage in GBPH, SBPH, and IDPC groups was 23.6%, 27.2%, and 6.4%, respectively. The percentage of voxels with lipid peak at the edge of the central gland (79.6%, 68.6% and 72.4%, respectively) was higher than that in other regions. The lipid peak in most of the voxels didn't influence the identification of the citrate and choline peak (82.8%, 98.0%, and 96.4%, respectively). Conclusion: The lipid peak in the central gland may result from the lipid tissues near the gland, and most lipid peak had no influence on the identification of endogenous metabolites. (authors)

  2. Human endogenous retroviruses in neurologic disease.

    Science.gov (United States)

    Christensen, Tove

    2016-01-01

    Endogenous retroviruses are pathogenic - in other species than the human. Disease associations for Human Endogenous RetroViruses (HERVs) are emerging, but so far an unequivocal pathogenetic cause-effect relationship has not been established. A role for HERVs has been proposed in neurological and neuropsychiatric diseases as diverse as multiple sclerosis (MS) and schizophrenia (SCZ). Particularly for MS, many aspects of the activation and involvement of specific HERV families (HERV-H/F and HERV-W/MSRV) have been reported, both for cells in the circulation and in the central nervous system. Notably envelope genes and their gene products (Envs) appear strongly associated with the disease. For SCZ, for ALS, and for HIV-associated dementia (HAD), indications are accumulating for involvement of the HERV-K family, and also HERV-H/F and/or HERV-W. Activation is reasonably a prerequisite for causality as most HERV sequences remain quiescent in non-pathological conditions, so the importance of regulatory pathways and epigenetics involved in regulating HERV activation, derepression, and also involvement of retroviral restriction factors, is emerging. HERV-directed antiretrovirals have potential as novel therapeutic paradigms in neurologic disease, particularly in MS. The possible protective or ameliorative effects of antiretroviral therapy in MS are substantiated by reports that treatment of HIV infection may be associated with a significantly decreased risk of MS. Further studies of HERVs, their role in neurologic diseases, and their potential as therapeutic targets are essential. © 2016 APMIS. Published by John Wiley & Sons Ltd.

  3. Endogenous fibrinolysis facilitates clot retraction in vivo.

    Science.gov (United States)

    Samson, Andre L; Alwis, Imala; Maclean, Jessica A A; Priyananda, Pramith; Hawkett, Brian; Schoenwaelder, Simone M; Jackson, Shaun P

    2017-12-07

    Clot retraction refers to the process whereby activated platelets transduce contractile forces onto the fibrin network of a thrombus, which over time increases clot density and decreases clot size. This process is considered important for promoting clot stability and maintaining blood vessel patency. Insights into the mechanisms regulating clot retraction at sites of vascular injury have been hampered by a paucity of in vivo experimental models. By pairing localized vascular injury with thrombin microinjection in the mesenteric circulation of mice, we have demonstrated that the fibrin network of thrombi progressively compacts over a 2-hour period. This was a genuine retraction process, as treating thrombi with blebbistatin to inhibit myosin IIa-mediated platelet contractility prevented shrinkage of the fibrin network. Real-time confocal analysis of fibrinolysis after recombinant tissue-type plasminogen activator (tPA) administration revealed that incomplete proteolysis of fibrin polymers markedly facilitated clot retraction. Similarly, inhibiting endogenous fibrinolysis with tranexamic acid reduced retraction of fibrin polymers in vivo. In vitro clot retraction experiments indicated that subthreshold doses of tPA facilitated clot retraction through a plasmin-dependent mechanism. These effects correlated with changes in the elastic modulus of fibrin clots. These findings define the endogenous fibrinolytic system as an important regulator of clot retraction, and show that promoting clot retraction is a novel and complementary means by which fibrinolytic enzymes can reduce thrombus size. © 2017 by The American Society of Hematology.

  4. Endogenous antispermatogenic agents: prospects for male contraception.

    Science.gov (United States)

    Ewing, L L; Robaire, B

    1978-01-01

    A review of endogenous antispermatogenic agents as prospects for male contraception is reported. It is demonstrated that endogenous compounds exert regulatory influences at 4 major levels in the male: 1) between germ cells; 2) between Sertoli and germ cells; 3) between Leydig cells and seminiferous tubules; and 4) between the central nervous system and the testis. Efforts to interrupt spermatogenesis have failed to find application as male contraceptives for various reasons: 1) some investigators ignored the vulnerable control points by utilizing nonspecific agents; 2) others attacked a vulnerable control point but used synthetic drugs that had deleterious side effects; and 3) still others attacked a vulnerable control point with a relatively innocuous drug but used an impractical mode of drug administration. The potential for devising innovative techniques for administering relatively innocuous drugs at dosages sufficient to produce sterility without causing deleterious side effects is demonstrated. The most promising solution for the development of an antispermatogenic male contraceptive is the interference with the adenohypophyseal-gonadal axis via the subcutaneous sustained release of steroid formulations containing either androgen-danazol, androgen-progestin, or androgen-estrogen formulations. Another promising agent would be luteinizing releasing hormone agonist-androgen formulation.

  5. Insertional Polymorphisms of Endogenous Feline Leukemia Viruses

    Science.gov (United States)

    Roca, Alfred L.; Nash, William G.; Menninger, Joan C.; Murphy, William J.; O'Brien, Stephen J.

    2005-01-01

    The number, chromosomal distribution, and insertional polymorphisms of endogenous feline leukemia viruses (enFeLVs) were determined in four domestic cats (Burmese, Egyptian Mau, Persian, and nonbreed) using fluorescent in situ hybridization and radiation hybrid mapping. Twenty-nine distinct enFeLV loci were detected across 12 of the 18 autosomes. Each cat carried enFeLV at only 9 to 16 of the loci, and many loci were heterozygous for presence of the provirus. Thus, an average of 19 autosomal copies of enFeLV were present per cat diploid genome. Only five of the autosomal enFeLV sites were present in all four cats, and at only one autosomal locus, B4q15, was enFeLV present in both homologues of all four cats. A single enFeLV occurred in the X chromosome of the Burmese cat, while three to five enFeLV proviruses occurred in each Y chromosome. The X chromosome and nine autosomal enFeLV loci were telomeric, suggesting that ectopic recombination between nonhomologous subtelomeres may contribute to enFeLV distribution. Since endogenous FeLVs may affect the infectiousness or pathogenicity of exogenous FeLVs, genomic variation in enFeLVs represents a candidate for genetic influences on FeLV leukemogenesis in cats. PMID:15767400

  6. Endogenous Technology Adoption and Medical Costs.

    Science.gov (United States)

    Lamiraud, Karine; Lhuillery, Stephane

    2016-09-01

    Despite the claim that technology has been one of the most important drivers of healthcare spending growth over the past decades, technology variables are rarely introduced explicitly in cost equations. Furthermore, technology is often considered exogenous. Using 1996-2007 panel data on Swiss geographical areas, we assessed the impact of technology availability on per capita healthcare spending covered by basic health insurance whilst controlling for the endogeneity of health technology availability variables. Our results suggest that medical research, patent intensity and the density of employees working in the medical device industry are influential factors for the adoption of technology and can be used as instruments for technology availability variables in the cost equation. These results are similar to previous findings: CT and PET scanner adoption is associated with increased healthcare spending, whilst increased availability of percutaneous transluminal coronary angioplasty facilities is associated with reductions in per capita spending. However, our results suggest that the magnitude of these relationships is much greater in absolute value than that suggested by previous studies that did not control for the possible endogeneity of the availability of technologies. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Lipid Cell Biology: A Focus on Lipids in Cell Division.

    Science.gov (United States)

    Storck, Elisabeth M; Özbalci, Cagakan; Eggert, Ulrike S

    2018-06-20

    Cells depend on hugely diverse lipidomes for many functions. The actions and structural integrity of the plasma membrane and most organelles also critically depend on membranes and their lipid components. Despite the biological importance of lipids, our understanding of lipid engagement, especially the roles of lipid hydrophobic alkyl side chains, in key cellular processes is still developing. Emerging research has begun to dissect the importance of lipids in intricate events such as cell division. This review discusses how these structurally diverse biomolecules are spatially and temporally regulated during cell division, with a focus on cytokinesis. We analyze how lipids facilitate changes in cellular morphology during division and how they participate in key signaling events. We identify which cytokinesis proteins are associated with membranes, suggesting lipid interactions. More broadly, we highlight key unaddressed questions in lipid cell biology and techniques, including mass spectrometry, advanced imaging, and chemical biology, which will help us gain insights into the functional roles of lipids.

  8. Lipid Uptake, Metabolism, and Transport in the Larval Zebrafish

    Directory of Open Access Journals (Sweden)

    Vanessa H. Quinlivan

    2017-11-01

    Full Text Available The developing zebrafish is a well-established model system for studies of energy metabolism, and is amenable to genetic, physiological, and biochemical approaches. For the first 5 days of life, nutrients are absorbed from its endogenous maternally deposited yolk. At 5 days post-fertilization, the yolk is exhausted and the larva has a functional digestive system including intestine, liver, gallbladder, pancreas, and intestinal microbiota. The transparency of the larval zebrafish, and the genetic and physiological similarity of its digestive system to that of mammals make it a promising system in which to address questions of energy homeostasis relevant to human health. For example, apolipoprotein expression and function is similar in zebrafish and mammals, and transgenic animals may be used to examine both the transport of lipid from yolk to body in the embryo, and the trafficking of dietary lipids in the larva. Additionally, despite the identification of many fatty acid and lipid transport proteins expressed by vertebrates, the cell biological processes that mediate the transport of dietary lipids from the intestinal lumen to the interior of enterocytes remain to be elucidated. Genetic tractability and amenability to live imaging and a range of biochemical methods make the larval zebrafish an ideal model in which to address open questions in the field of lipid transport, energy homeostasis, and nutrient metabolism.

  9. Metabolic control by S6 kinases depends on dietary lipids.

    Directory of Open Access Journals (Sweden)

    Tamara R Castañeda

    Full Text Available Targeted deletion of S6 kinase (S6K 1 in mice leads to higher energy expenditure and improved glucose metabolism. However, the molecular mechanisms controlling these effects remain to be fully elucidated. Here, we analyze the potential role of dietary lipids in regulating the mTORC1/S6K system. Analysis of S6K phosphorylation in vivo and in vitro showed that dietary lipids activate S6K, and this effect is not dependent upon amino acids. Comparison of male mice lacking S6K1 and 2 (S6K-dko with wt controls showed that S6K-dko mice are protected against obesity and glucose intolerance induced by a high-fat diet. S6K-dko mice fed a high-fat diet had increased energy expenditure, improved glucose tolerance, lower fat mass gain, and changes in markers of lipid metabolism. Importantly, however, these metabolic phenotypes were dependent upon dietary lipids, with no such effects observed in S6K-dko mice fed a fat-free diet. These changes appear to be mediated via modulation of cellular metabolism in skeletal muscle, as shown by the expression of genes involved in energy metabolism. Taken together, our results suggest that the metabolic functions of S6K in vivo play a key role as a molecular interface connecting dietary lipids to the endogenous control of energy metabolism.

  10. Pharmacogenetics of lipid diseases

    Directory of Open Access Journals (Sweden)

    Ordovas Jose M

    2004-01-01

    Full Text Available Abstract The genetic basis for most of the rare lipid monogenic disorders have been elucidated, but the challenge remains in determining the combination of genes that contribute to the genetic variability in lipid levels in the general population; this has been estimated to be in the range of 40-60 per cent of the total variability. Therefore, the effect of common polymorphisms on lipid phenotypes will be greatly modulated by gene-gene and gene-environment interactions. This approach can also be used to characterise the individuality of the response to lipid-lowering therapies, whether using drugs (pharmacogenetics or dietary interventions (nutrigenetics. In this regard, multiple studies have already described significant interactions between candidate genes for lipid and drug metabolism that modulate therapeutic response--although the outcomes of these studies have been controversial and call for more rigorous experimental design and analytical approaches. Once solid evidence about the predictive value of genetic panels is obtained, risk and therapeutic algorithms can begin to be generated that should provide an accurate measure of genetic predisposition, as well as targeted behavioural modifications or drugs of choice and personalised dosages of these drugs.

  11. Changes in endogenous hormone concentrations during ...

    African Journals Online (AJOL)

    Administrator

    2011-09-14

    Sep 14, 2011 ... acid (GA3) and zeatin (ZT), and led to the transition of vegetative growth to inflorescence initiation. After ... Pineapple (Ananas comosus (L.) Merril) is native to southern Brazil and ... formalin acetic alcohol (FAA) solutions for anatomy analysis; and ..... plants, and is abundant in the will-be falling organs and.

  12. Endogenous UVA-photosensitizers: mediators of skin photodamage and novel targets for skin photoprotection.

    Science.gov (United States)

    Wondrak, Georg T; Jacobson, Myron K; Jacobson, Elaine L

    2006-02-01

    Endogenous chromophores in human skin serve as photosensitizers involved in skin photocarcinogenesis and photoaging. Absorption of solar photons, particularly in the UVA region, induces the formation of photoexcited states of skin photosensitizers with subsequent generation of reactive oxygen species (ROS), organic free radicals and other toxic photoproducts that mediate skin photooxidative stress. The complexity of endogenous skin photosensitizers with regard to molecular structure, pathways of formation, mechanisms of action, and the diversity of relevant skin targets has hampered progress in this area of photobiology and most likely contributed to an underestimation of the importance of endogenous sensitizers in skin photodamage. Recently, UVA-fluorophores in extracellular matrix proteins formed posttranslationally as a consequence of enzymatic maturation or spontaneous chemical damage during chronological and actinic aging have been identified as an abundant source of light-driven ROS formation in skin upstream of photooxidative cellular stress. Importantly, sensitized skin cell photodamage by this bystander mechanism occurs after photoexcitation of sensitizers contained in skin structural proteins without direct cellular photon absorption thereby enhancing the potency and range of phototoxic UVA action in deeper layers of skin. The causative role of photoexcited states in skin photodamage suggests that direct molecular antagonism of photosensitization reactions using physical quenchers of photoexcited states offers a novel chemopreventive opportunity for skin photoprotection.

  13. Lipids, lipid bilayers and vesicles as seen by neutrons

    International Nuclear Information System (INIS)

    Seto, Hideki

    2011-01-01

    Lipid molecules self-assemble into bilayers in water with their hydrocarbon chains facing inward due to their amphiphilic nature. The structural and dynamical properties of lipids and lipid bilayers have been studied by neutron scattering intensively. In this article, 3 topics are shown as typical examples. 1) a time-resolved small-angle neutron scattering on uni-lamellar vesicles composed of deuterated and protonated lipids to determine lipid kinetics, 2) small-angle neutron scattering to investigate spontaneous formation of nanopores on uni-lamellar vesicles, and 3) neutron spin echo study to determine bending modulus of lipid bilayers. (author)

  14. Effect of chloroquine on intestinal lipid metabolism

    International Nuclear Information System (INIS)

    Mansbach, C.M. II; Arnold, A.; Garrett, M.

    1987-01-01

    Most studies that have quantitated recovery of infused lipid in the intestinal mucosa and mesenteric lymph have only been able to recapture 50-75%. One possibility is that the missing lipid enters a triacylglycerol (TG) storage pool in the enterocyte and is hydrolyzed by lysosomal lipase, and the free fatty acid released is transported by the portal vein. This postulate was tested by comparing glyceryl trioleate (TO)-infused rats pretreated with the lysosomotropic drug, chloroquine (6.3 mg.kg-1.h-1) with saline controls. Chloroquine increased mucosal TG from 94 +/- 6 to 128 +/- 8 mumol. Additionally, the specific activity of the mucosal TG relative to the infused [ 3 H]TO was reduced in the treated rats. The mucosal TG increase was not due to impaired TG output, which remained the same as controls. We conclude that the TG in the acid lipase-sensitive pool derives most of its glyceride-glycerol from endogenous sources. Furthermore, the increment in mucosal TG caused by chloroquine is not enough to explain the majority of the acyl groups unaccounted for in the mucosa and lymph after a TG infusion. For these a direct passage of acyl groups through the enterocyte is postulated

  15. Lipid management in ramadan.

    Science.gov (United States)

    Slim, Ines; Ach, Koussay; Chaieb, Larbi

    2015-05-01

    During Ramadan fast, Muslims must refrain from smoking, eating, drinking, having sexual activity, and consuming oral medications from sunrise to sunset. It has been previously shown that Ramadan fasting induces favourable changes on metabolic parameters, reduces oxidative stress and inflammation and promotes cardiovascular benefits. Although ill people are exempted from fasting, most patients with chronic diseases are keen on performing this Islamic-ritual. During recent years, Risk stratification and treatment adjustment during Ramadan are well known and structured in several guidelines for patients with diabetes mellitus. Data related to the effect of Ramadan fast on lipid profiles are less known and several controversies have been reported. Here, we focus on lipid profile and lipid management during Ramadan taking into account comorbidities and cardiovascular risk.

  16. Heart, lipids and hormones

    Directory of Open Access Journals (Sweden)

    Peter Wolf

    2017-05-01

    Full Text Available Cardiovascular disease is the leading cause of death in general population. Besides well-known risk factors such as hypertension, impaired glucose tolerance and dyslipidemia, growing evidence suggests that hormonal changes in various endocrine diseases also impact the cardiac morphology and function. Recent studies highlight the importance of ectopic intracellular myocardial and pericardial lipid deposition, since even slight changes of these fat depots are associated with alterations in cardiac performance. In this review, we overview the effects of hormones, including insulin, thyroid hormones, growth hormone and cortisol, on heart function, focusing on their impact on myocardial lipid metabolism, cardiac substrate utilization and ectopic lipid deposition, in order to highlight the important role of even subtle hormonal changes for heart function in various endocrine and metabolic diseases.

  17. International Environmental Agreements with Endogenous or Exogenous Risk

    OpenAIRE

    Fuhai Hong; Larry Karp

    2014-01-01

    We examine the effect of endogenous and exogenous risk on the equilibrium (expected) membership of an International Environmental Agreement when countries are risk averse. Endogenous risk arises when countries use mixed rather than pure strategies at the participation game, and exogenous risk arises from the inherent uncertainty about the costs and benefits of increased abate- ment. Under endogenous risk, an increase in risk aversion increases expected participation. Under exogenous risk and ...

  18. Horizontalists, verticalists, and structuralists: The theory of endogenous money reassessed

    OpenAIRE

    Palley, Thomas I.

    2013-01-01

    This paper uses the occasion of the twenty-fifth anniversary of Basil Moore’s book, Horizontalists and Verticalists, to reassess the theory of endogenous money. The paper distinguishes between horizontalists, verticalists, and structuralists. It argues Moore’s horizontalist representation of endogenous money was an over-simplification that discarded important enduring insights from monetary theory. The structuralist approach to endogenous money retains the basic insight that the money supply ...

  19. Energy and lipid metabolism during direct and diapause development in a pierid butterfly.

    Science.gov (United States)

    Lehmann, Philipp; Pruisscher, Peter; Posledovich, Diana; Carlsson, Mikael; Käkelä, Reijo; Tang, Patrik; Nylin, Sören; Wheat, Christopher W; Wiklund, Christer; Gotthard, Karl

    2016-10-01

    Diapause is a fundamental component of the life cycle in the majority of insects living in environments characterized by strong seasonality. The present study addresses poorly understood associations and trade-offs between endogenous diapause duration, thermal sensitivity of development, energetic cost of development and cold tolerance. Diapause intensity, metabolic rate trajectories and lipid profiles of directly developing and diapausing animals were studied using pupae and adults of Pieris napi butterflies from a population in which endogenous diapause has been well studied. Endogenous diapause was terminated after 3 months and termination required chilling. Metabolic and post-diapause development rates increased with diapause duration, while the metabolic cost of post-diapause development decreased, indicating that once diapause is terminated, development proceeds at a low rate even at low temperature. Diapausing pupae had larger lipid stores than the directly developing pupae, and lipids constituted the primary energy source during diapause. However, during diapause, lipid stores did not decrease. Thus, despite lipid catabolism meeting the low energy costs of the diapausing pupae, primary lipid store utilization did not occur until the onset of growth and metamorphosis in spring. In line with this finding, diapausing pupae contained low amounts of mitochondria-derived cardiolipins, which suggests a low capacity for fatty acid β-oxidation. While ontogenic development had a large effect on lipid and fatty acid profiles, only small changes in these were seen during diapause. The data therefore indicate that the diapause lipidomic phenotype is developed early, when pupae are still at high temperature, and retained until post-diapause development. © 2016. Published by The Company of Biologists Ltd.

  20. Endogenous fatty acid ethanolamides suppress nicotine-induced activation of mesolimbic dopamine neurons through nuclear receptors.

    Science.gov (United States)

    Melis, Miriam; Pillolla, Giuliano; Luchicchi, Antonio; Muntoni, Anna Lisa; Yasar, Sevil; Goldberg, Steven R; Pistis, Marco

    2008-12-17

    Nicotine stimulates the activity of mesolimbic dopamine neurons, which is believed to mediate the rewarding and addictive properties of tobacco use. Accumulating evidence suggests that the endocannabinoid system might play a major role in neuronal mechanisms underlying the rewarding properties of drugs of abuse, including nicotine. Here, we investigated the modulation of nicotine effects by the endocannabinoid system on dopamine neurons in the ventral tegmental area with electrophysiological techniques in vivo and in vitro. We discovered that pharmacological inhibition of fatty acid amide hydrolase (FAAH), the enzyme that catabolizes fatty acid ethanolamides, among which the endocannabinoid anandamide (AEA) is the best known, suppressed nicotine-induced excitation of dopamine cells. Importantly, this effect was mimicked by the administration of the FAAH substrates oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), but not methanandamide, the hydrolysis resistant analog of AEA. OEA and PEA are naturally occurring lipid signaling molecules structurally related to AEA, but devoid of affinity for cannabinoid receptors. They blocked the effects of nicotine by activation of the peroxisome proliferator-activated receptor-alpha (PPAR-alpha), a nuclear receptor transcription factor involved in several aspects of lipid metabolism and energy balance. Activation of PPAR-alpha triggered a nongenomic stimulation of tyrosine kinases, which might lead to phosphorylation and negative regulation of neuronal nicotinic acetylcholine receptors. These data indicate for the first time that the anorexic lipids OEA and PEA possess neuromodulatory properties as endogenous ligands of PPAR-alpha in the brain and provide a potential new target for the treatment of nicotine addiction.

  1. 13C/12C natural abundance ratios as an indicator of changes in plant respiratory pathways

    International Nuclear Information System (INIS)

    Smith, B.N.

    1975-01-01

    Changes in metabolism which involve a shift in endogenous respiratory substrate can be detected from isotopic ratios of respired CO 2 . Various plant tissues including seedlings, flowers and storage tissues, which during development or in response to environmental stimulus experience a change in metabolism, have been examined. Respiratory CO 2 was collected in a series of traps from a stream of CO 2 -free air. Biochemical fractions were combusted at 800 0 C and the CO 2 recovered for analysis. Samples were then analyzed on an isotope ratio mass spectrometer. Due to large isotopic differences between lipid and carbohydrate fractions, change from one to the other as respiratory substrate can be detected. Storage starch in potato tuber seems not to be utilized for respiration until the stimulus for new growth is received. Similarly, the time of onset of lipid utilization in fatty seeds can be detected during germination. Flowering in the Araceae involves a great burst of carbohydrate-base respiration followed by a shift to lipid metabolism. The endogenous source of ethylene in peanuts and the extent of CO 2 refixation during photorespiration has also been estimated by this technique

  2. Are human endogenous retroviruses triggers of autoimmune diseases?

    DEFF Research Database (Denmark)

    Nexø, Bjørn A; Villesen, Palle; Nissen, Kari K

    2016-01-01

    factors. Viruses including human endogenous retroviruses have long been linked to the occurrence of autoimmunity, but never proven to be causative factors. Endogenous viruses are retroviral sequences embedded in the host germline DNA and transmitted vertically through successive generations in a Mendelian...... manner. In this study by means of genetic epidemiology, we have searched for the involvement of endogenous retroviruses in three selected autoimmune diseases: multiple sclerosis, type 1 diabetes mellitus, and rheumatoid arthritis. We found that at least one human endogenous retroviral locus...

  3. Sucessfull management of bilateral presumed Candida endogenous endophtalmitis following pancreatitis

    Directory of Open Access Journals (Sweden)

    Ricardo Evangelista Marrocos de Aragão

    2016-06-01

    Full Text Available ABSTRACT Endogenous endophthalmitis is a rare, and frequently devastating, ophthalmic disease. It occurs mostly in immunocompromised patients, or those with diabetes mellitus, cancer or intravenous drugs users. Candida infection is the most common cause of endogenous endophthalmitis. Ocular candidiasis develops within days to weeks of fungemia. The association of treatment for pancreatitis with endophthalmitis is unusual. Treatment with broad-spectrum antibiotics and total parenteral nutrition may explain endogenous endophthalmitis. We report the case of a patient with pancreatitis treated with broad-spectrum antibiotics and total parenteral nutrition who developed bilateral presumed Candida endogenous endophthalmitis that was successfully treated with vitrectomy and intravitreal amphotericin B.

  4. Lipid composition of phytoplankton from the Barents Sea and environmental influences on the distribution pattern of carbon among photosynthetic end products

    OpenAIRE

    Henderson, R. James; Olsen, Rolf E.; Eilertsen, Hans C.

    1991-01-01

    The colonial algae Phaeocystis pouchetii and Dinobryon pellucidum dominated the phytoplankton crop at three stations in the Polar Front area of the Barents Sea. Lipid extracted from the seawater containing the phytoplankton was dominated by neutral lipid classes, particularly triacylglycerols, and phospholipids were more abundant than galactolipids at all stations. Polyunsaturated fatty acids comprised between 15 and 26% of fatty acids of total lipid. Of the carbon assimilated into lipid over...

  5. Changing Endogenous Development: the Territorial Capital

    Directory of Open Access Journals (Sweden)

    Balázs István Tóth

    2011-12-01

    Full Text Available The aim of this research is to analyze territorial capital as a new paradigm to make best use of endogenous assets. The study is dealing with the preconditions, meaning and possible theoretical taxonomies of territorial capital. In this study I emphasize that the cumulative effects of regional potentials are more important than economies of scale and location factors. I present different approaches and interpretations of territorial capital, then make an attempt to create an own model. I try to find answers for questions, such as why territorial capital shows a new perspective of urban and regional development; how cognitive elements of territorial capital provide increasing return; how territorial capital influences competitiveness and what kind of relation it has with cohesion.

  6. Public Procurement of Innovation as Endogenous

    DEFF Research Database (Denmark)

    Rolfstam, Max

    Public procurement used as an innovation policy instrument has attracted attention the last decade. It has been argued that public procurement can be used to stimulate innovation from the demand-side. This paper problematizes ‘demand’ understood as a problem defined by a public procurer given...... to potential suppliers to solve. By drawing on a cross-case analysis of two similar projects the paper attempts to explicate an understanding of the role of public procurement of innovation not primarily as a ‘demand-side innovation instrument’, as such thinking might run the risk of ignoring important...... underlying mechanisms critical for success. Instead the paper views public procurement of innovation as an instrument of endogenous- exogenous knowledge conversion....

  7. Endogenous Markups, Firm Productivity and International Trade:

    DEFF Research Database (Denmark)

    Bellone, Flora; Musso, Patrick; Nesta, Lionel

    ) markups are positively related to firm productivity; 3) markups are negatively related to import penetration; 4) markups are positively related to firm export intensity and markups are higher on the export market than on the domestic ones in the presence of trade barriers and/or if competitors...... on the export market are less efficient than competitors on the domestic market. We estimate micro-level price cost margins (PCMs) using firm-level data extending the techniques developed by Hall (1986, 1988) and extended by Domowitz et al. (1988) and Roeger (1995) for the French manufacturing industry from......In this paper, we test key micro-level theoretical predictions ofMelitz and Ottaviano (MO) (2008), a model of international trade with heterogenous firms and endogenous mark-ups. At the firm-level, the MO model predicts that: 1) firm markups are negatively related to domestic market size; 2...

  8. Involvement of Endogenous Retroviruses in Prion Diseases

    Directory of Open Access Journals (Sweden)

    Yong-Sun Kim

    2013-08-01

    Full Text Available For millions of years, vertebrates have been continuously exposed to infection by retroviruses. Ancient retroviral infection of germline cells resulted in the formation and accumulation of inherited retrovirus sequences in host genomes. These inherited retroviruses are referred to as endogenous retroviruses (ERVs, and recent estimates have revealed that a significant portion of animal genomes is made up of ERVs. Although various host factors have suppressed ERV activation, both positive and negative functions have been reported for some ERVs in normal and abnormal physiological conditions, such as in disease states. Similar to other complex diseases, ERV activation has been observed in prion diseases, and this review will discuss the potential involvement of ERVs in prion diseases.

  9. Exogenous and endogenous landforms in the Mediterranean

    Science.gov (United States)

    Acar, Julia

    2017-04-01

    11th graders have already learned about endogenous forces and now we are having a closer look at the exogenous forces which act on the Earth's surface. The Po River-system, for example, is responsible for the formation of the alpine region. Students are asked to find out how this works with the help of the rock-cycle scheme, several suitable maps and information on weathering and the texture of rocks, erosion, etc. We will form groups that will look at different types of rock formations (including an example in the Mediterranean region each). Depending on the number of lessons available we will add the exogenous effect of flowing water and ice (glacial over forming) to the topic. At the end every group will present their findings explaining the scientific context by using topographic examples.

  10. Unfunded pensions and endogenous labor supply

    DEFF Research Database (Denmark)

    Andersen, Torben M.; Bhattacharya, Joydeep

    A classic result in dynamic public economics, dating back to Aaron (1966) and Samuelson (1975), states that there is no welfare rationale for PAYG pensions in a dynamically-efficient neoclassical economy with exogenous labor supply. This paper argues that this result, under the fairly-mild restri......A classic result in dynamic public economics, dating back to Aaron (1966) and Samuelson (1975), states that there is no welfare rationale for PAYG pensions in a dynamically-efficient neoclassical economy with exogenous labor supply. This paper argues that this result, under the fairly......-mild restriction that the old be no less risk-averse than the young, extends to a neoclassical economy with endogenous labor supply....

  11. Transfer of endogenous pyrogens across artificial membranes?

    Science.gov (United States)

    Lonnemann, G; Linnenweber, S; Burg, M; Koch, K M

    1998-05-01

    Synthetic high-flux dialyzer membranes used in continuous veno-venous hemofiltration are permeable to middle molecular size endogenous pyrogens, the pro-inflammatory cytokines IL-1 beta and TNF-alpha. The quantities removed by sieving are, however, negligible in vitro as well as in vivo. Adsorption of cytokines to the membrane polymer is the major mechanism of pyrogen removal. Adsorption seems to be semispecific for pro-inflammatory cytokines because levels of anti-inflammatory mediators were not changed or even increased during CVVH. Thus, CVVH may change cytokine profiles in septic patients supporting the predominance of anti-inflammatory over pro-inflammatory activity in plasma. It remains to be demonstrated whether modifications of extracorporeal blood purification systems (high-volume CVVH, plasma separation + adsorption) are able to amplify the change in cytokine profiles and whether this change influences outcome of septic patients.

  12. Endogenous Methanol Regulates Mammalian Gene Activity

    Science.gov (United States)

    Komarova, Tatiana V.; Petrunia, Igor V.; Shindyapina, Anastasia V.; Silachev, Denis N.; Sheshukova, Ekaterina V.; Kiryanov, Gleb I.; Dorokhov, Yuri L.

    2014-01-01

    We recently showed that methanol emitted by wounded plants might function as a signaling molecule for plant-to-plant and plant-to-animal communications. In mammals, methanol is considered a poison because the enzyme alcohol dehydrogenase (ADH) converts methanol into toxic formaldehyde. However, the detection of methanol in the blood and exhaled air of healthy volunteers suggests that methanol may be a chemical with specific functions rather than a metabolic waste product. Using a genome-wide analysis of the mouse brain, we demonstrated that an increase in blood methanol concentration led to a change in the accumulation of mRNAs from genes primarily involved in detoxification processes and regulation of the alcohol/aldehyde dehydrogenases gene cluster. To test the role of ADH in the maintenance of low methanol concentration in the plasma, we used the specific ADH inhibitor 4-methylpyrazole (4-MP) and showed that intraperitoneal administration of 4-MP resulted in a significant increase in the plasma methanol, ethanol and formaldehyde concentrations. Removal of the intestine significantly decreased the rate of methanol addition to the plasma and suggested that the gut flora may be involved in the endogenous production of methanol. ADH in the liver was identified as the main enzyme for metabolizing methanol because an increase in the methanol and ethanol contents in the liver homogenate was observed after 4-MP administration into the portal vein. Liver mRNA quantification showed changes in the accumulation of mRNAs from genes involved in cell signalling and detoxification processes. We hypothesized that endogenous methanol acts as a regulator of homeostasis by controlling the mRNA synthesis. PMID:24587296

  13. Dynamic option pricing with endogenous stochastic arbitrage

    Science.gov (United States)

    Contreras, Mauricio; Montalva, Rodrigo; Pellicer, Rely; Villena, Marcelo

    2010-09-01

    Only few efforts have been made in order to relax one of the key assumptions of the Black-Scholes model: the no-arbitrage assumption. This is despite the fact that arbitrage processes usually exist in the real world, even though they tend to be short-lived. The purpose of this paper is to develop an option pricing model with endogenous stochastic arbitrage, capable of modelling in a general fashion any future and underlying asset that deviate itself from its market equilibrium. Thus, this investigation calibrates empirically the arbitrage on the futures on the S&P 500 index using transaction data from September 1997 to June 2009, from here a specific type of arbitrage called “arbitrage bubble”, based on a t-step function, is identified and hence used in our model. The theoretical results obtained for Binary and European call options, for this kind of arbitrage, show that an investment strategy that takes advantage of the identified arbitrage possibility can be defined, whenever it is possible to anticipate in relative terms the amplitude and timespan of the process. Finally, the new trajectory of the stock price is analytically estimated for a specific case of arbitrage and some numerical illustrations are developed. We find that the consequences of a finite and small endogenous arbitrage not only change the trajectory of the asset price during the period when it started, but also after the arbitrage bubble has already gone. In this context, our model will allow us to calibrate the B-S model to that new trajectory even when the arbitrage already started.

  14. How Active Are Porcine Endogenous Retroviruses (PERVs?

    Directory of Open Access Journals (Sweden)

    Joachim Denner

    2016-08-01

    Full Text Available Porcine endogenous retroviruses (PERVs represent a risk factor if porcine cells, tissues, or organs were to be transplanted into human recipients to alleviate the shortage of human transplants; a procedure called xenotransplantation. In contrast to human endogenous retroviruses (HERVs, which are mostly defective and not replication-competent, PERVs are released from normal pig cells and are infectious. PERV-A and PERV-B are polytropic viruses infecting cells of several species, among them humans; whereas PERV-C is an ecotropic virus infecting only pig cells. Virus infection was shown in co-culture experiments, but also in vivo, in the pig, leading to de novo integration of proviruses in certain organs. This was shown by measurement of the copy number per cell, finding different numbers in different organs. In addition, recombinations between PERV-A and PERV-C were observed and the recombinant PERV-A/C were found to be integrated in cells of different organs, but not in the germ line of the animals. Here, the evidence for such in vivo activities of PERVs, including expression as mRNA, protein and virus particles, de novo infection and recombination, will be summarised. These activities make screening of pigs for provirus number and PERV expression level difficult, especially when only blood or ear biopsies are available for analysis. Highly sensitive methods to measure the copy number and the expression level will be required when selecting pigs with low copy number and low expression of PERV as well as when inactivating PERVs using the clustered regularly interspaced short palindromic repeats (CRISPR/CRISPR-associated nuclease (CRISPR/Cas technology.

  15. Endogenous methanol regulates mammalian gene activity.

    Directory of Open Access Journals (Sweden)

    Tatiana V Komarova

    Full Text Available We recently showed that methanol emitted by wounded plants might function as a signaling molecule for plant-to-plant and plant-to-animal communications. In mammals, methanol is considered a poison because the enzyme alcohol dehydrogenase (ADH converts methanol into toxic formaldehyde. However, the detection of methanol in the blood and exhaled air of healthy volunteers suggests that methanol may be a chemical with specific functions rather than a metabolic waste product. Using a genome-wide analysis of the mouse brain, we demonstrated that an increase in blood methanol concentration led to a change in the accumulation of mRNAs from genes primarily involved in detoxification processes and regulation of the alcohol/aldehyde dehydrogenases gene cluster. To test the role of ADH in the maintenance of low methanol concentration in the plasma, we used the specific ADH inhibitor 4-methylpyrazole (4-MP and showed that intraperitoneal administration of 4-MP resulted in a significant increase in the plasma methanol, ethanol and formaldehyde concentrations. Removal of the intestine significantly decreased the rate of methanol addition to the plasma and suggested that the gut flora may be involved in the endogenous production of methanol. ADH in the liver was identified as the main enzyme for metabolizing methanol because an increase in the methanol and ethanol contents in the liver homogenate was observed after 4-MP administration into the portal vein. Liver mRNA quantification showed changes in the accumulation of mRNAs from genes involved in cell signalling and detoxification processes. We hypothesized that endogenous methanol acts as a regulator of homeostasis by controlling the mRNA synthesis.

  16. Direct observation of the influence of cardiolipin and antibiotics on lipid II binding to MurJ

    Science.gov (United States)

    Bolla, Jani Reddy; Sauer, Joshua B.; Wu, Di; Mehmood, Shahid; Allison, Timothy M.; Robinson, Carol V.

    2018-03-01

    Translocation of lipid II across the cytoplasmic membrane is essential in peptidoglycan biogenesis. Although most steps are understood, identifying the lipid II flippase has yielded conflicting results, and the lipid II binding properties of two candidate flippases—MurJ and FtsW—remain largely unknown. Here we apply native mass spectrometry to both proteins and characterize lipid II binding. We observed lower levels of lipid II binding to FtsW compared to MurJ, consistent with MurJ having a higher affinity. Site-directed mutagenesis of MurJ suggests that mutations at A29 and D269 attenuate lipid II binding to MurJ, whereas chemical modification of A29 eliminates binding. The antibiotic ramoplanin dissociates lipid II from MurJ, whereas vancomycin binds to form a stable complex with MurJ:lipid II. Furthermore, we reveal cardiolipins associate with MurJ but not FtsW, and exogenous cardiolipins reduce lipid II binding to MurJ. These observations provide insights into determinants of lipid II binding to MurJ and suggest roles for endogenous lipids in regulating substrate binding.

  17. Biased signaling of lipids and allosteric actions of synthetic molecules for GPR119

    DEFF Research Database (Denmark)

    Hassing, Helle A; Fares, Suzan; Larsen, Olav

    2016-01-01

    for 2h with the 2-MAG-lipase inhibitor JZL84 doubled the constitutive activity, indicating that endogenous lipids contribute to the apparent constitutive activity. Finally, besides being an agonist, AR231453 acted as a positive allosteric modulator of OEA and increased its potency by 54-fold at 100nM AR......231453. Our studies uncovering broad and biased signaling, masked constitutive activity by endogenous MAGs, and ago-allosteric properties of synthetic ligands may explain why many GPR119 drug-discovery programs have failed so far....

  18. Lipids in airway secretions

    International Nuclear Information System (INIS)

    Bhaskar, K.R.; DeFeudis O'Sullivan, D.; Opaskar-Hincman, H.; Reid, L.M.

    1987-01-01

    Lipids form a significant portion of airway mucus yet they have not received the same attention that epithelial glycoproteins have. We have analysed, by thin layer chromatography, lipids present in airway mucus under 'normal' and hypersecretory (pathological) conditions.The 'normals' included (1) bronchial lavage obtained from healthy human volunteers and from dogs and (2) secretions produced ''in vitro'' by human (bronchial) and canine (tracheal) explants. Hypersecretory mucus samples included (1) lavage from dogs made bronchitic by exposure to SO 2 , (2) bronchial aspirates from acute and chronic tracheostomy patients, (3) sputum from patients with cystic fibrosis and chronic bronchitis and (4) postmortem secretions from patients who died from sudden infant death syndrome (SIDS) or from status asthmaticus. Cholesterol was found to be the predominant lipid in 'normal' mucus with lesser amounts of phospholipids. No glycolipids were detected. In the hypersecretory mucus, in addition to neutral and phospholipids, glycolipids were present in appreciable amounts, often the predominant species, suggesting that these may be useful as markers of disease. Radioactive precursors 14 C acetate and 14 C palmitate were incorporated into lipids secreted ''in vitro'' by canine tracheal explants indicating that they are synthesised by the airway. (author)

  19. Exogenous lipid pneumonia

    International Nuclear Information System (INIS)

    Bernasconi, A.; Gavelli, G.; Zompatori, M.; Galleri, C.; Zanasi, A.; Fabbri, M.; Bazzocchi, F.

    1988-01-01

    Exogenous lipid pneumonia (ELP) is caused by the aspiration of animal, vegetal or, more often, mineral oils. Even though it may also be acute, ELP is most frequently a chronic disease, affecting people with predisposing factors, such as neuromuscular disorders, structural abnormalities and so on; very often exogenous lipid pneumonia is found in tracheotomized patients. The pathology of lipid pneumonia is a chronic inflammatory process evolving in foreign-body-like reaction, and eventually in ''end-stage lung'' condition. Clinically, most patients are asymptomatic; few cases only present with cough, dyspnea and chest pain. Eight cases of ELP, studied over the past 3 years, are described in this paper. All the patients were examined by chest radiographs and standard tomograms; 3 patients underwent CT. X-ray features were mono/bilateral consolidation of the lower zones, with air bronchogram and variable reduction in volume. CT density was not specific for fat tissue. In all cases the diagnosis was confirmed at biopsy. In 5 patients, followed for at least one year, clinical-radiological features showed no change. Thus, complications of ELP (especially malignant evolution) could be excluded. The authors conclude that lipid pneumonia must be considered in differential diagnosis of patients with history of usage of oils and compatible X-ray findings. The usefulness of an accurate follow-up is stressed

  20. Lipid Therapy for Intoxications

    NARCIS (Netherlands)

    Robben, Joris Henricus; Dijkman, Marieke Annet

    This review discusses the use of intravenous lipid emulsion (ILE) in the treatment of intoxications with lipophilic agents in veterinary medicine. Despite growing scientific evidence that ILE has merit in the treatment of certain poisonings, there is still uncertainty on the optimal composition of

  1. Lipid Therapy for Intoxications

    NARCIS (Netherlands)

    Robben, Joris Henricus; Dijkman, Marieke Annet

    2017-01-01

    This review discusses the use of intravenous lipid emulsion (ILE) in the treatment of intoxications with lipophilic agents in veterinary medicine. Despite growing scientific evidence that ILE has merit in the treatment of certain poisonings, there is still uncertainty on the optimal composition of

  2. THE PROCESSES OF ENDOGENIZING IN THE ENDOGENOUS GROWTH: THE CASE OF TURKEY

    Directory of Open Access Journals (Sweden)

    OSMAN DEMİR

    2013-06-01

    Full Text Available The aim of this study is to state how the main inputs of endogenous growth, i.e. knowledge, human capital and technological progress are made endogenous by education, R&D, university-industry cooperation, learning by doing and diffusion within the production process. Competitiveness of firms and countries would increase as educated people enter into workforce; as R&D produces new technologies which are used in the production process; as theoretical knowledge meets with practice by university-industry cooperation; and as workers have more experience by learning by doing. In empirical analysis for Turkey is made by using data of 1970-2001 term it was found that a positive relationship among labour and capital factors and GNP and a negative relationship among education expenditures and foreign trade volume and capital stock.

  3. An endogenous Taylor condition in an endogenous growth monetary policy model

    OpenAIRE

    Le, Mai Vo; Gillman, Max; Minford, Patrick

    2007-01-01

    The paper derives a Taylor condition as part of the agent's equilibrium behavior in an endogenous growth monetary economy. It shows the assumptions necessary to make it almost identical to the original Taylor rule, and that it can interchangably take a money supply growth rate form. From the money supply form, simple policy experiments are conducted. A full central bank policy model is derived that includes the Taylor condition along with equations comparable to the standard aggregate-demand/...

  4. Big, Fat World of Lipids

    Science.gov (United States)

    ... offered a more quantitative and systematic approach to lipids research. Much of the effort has been led by a research consortium called LIPID MAPS. With funding from the National Institutes of ...

  5. Amphotericin B Lipid Complex Injection

    Science.gov (United States)

    Amphotericin B lipid complex injection is used to treat serious, possibly life-threatening fungal infections in people who did ... respond or are unable to tolerate conventional amphotericin B therapy. Amphotericin B lipid complex injection is in ...

  6. Interaction of lysozyme with a tear film lipid layer model: A molecular dynamics simulation study.

    Science.gov (United States)

    Wizert, Alicja; Iskander, D Robert; Cwiklik, Lukasz

    2017-12-01

    The tear film is a thin multilayered structure covering the cornea. Its outermost layer is a lipid film underneath of which resides on an aqueous layer. This tear film lipid layer (TFLL) is itself a complex structure, formed by both polar and nonpolar lipids. It was recently suggested that due to tear film dynamics, TFLL contains inhomogeneities in the form of polar lipid aggregates. The aqueous phase of tear film contains lachrymal-origin proteins, whereby lysozyme is the most abundant. These proteins can alter TFLL properties, mainly by reducing its surface tension. However, a detailed nature of protein-lipid interactions in tear film is not known. We investigate the interactions of lysozyme with TFLL in molecular details by employing coarse-grained molecular dynamics simulations. We demonstrate that lysozyme, due to lateral restructuring of TFLL, is able to penetrate the tear lipid film embedded in inverse micellar aggregates. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. The Lipid Raft Proteome of African Trypanosomes Contains Many Flagellar Proteins.

    Science.gov (United States)

    Sharma, Aabha I; Olson, Cheryl L; Engman, David M

    2017-08-24

    Lipid rafts are liquid-ordered membrane microdomains that form by preferential association of 3-β-hydroxysterols, sphingolipids and raft-associated proteins often having acyl modifications. We isolated lipid rafts of the protozoan parasite Trypanosoma brucei and determined the protein composition of lipid rafts in the cell. This analysis revealed a striking enrichment of flagellar proteins and several putative signaling proteins in the lipid raft proteome. Calpains and intraflagellar transport proteins, in particular, were found to be abundant in the lipid raft proteome. These findings provide additional evidence supporting the notion that the eukaryotic cilium/flagellum is a lipid raft-enriched specialized structure with high concentrations of sterols, sphingolipids and palmitoylated proteins involved in environmental sensing and cell signaling.

  8. Do Endogenous and Exogenous Action Control Compete for Perception?

    Science.gov (United States)

    Pfister, Roland; Heinemann, Alexander; Kiesel, Andrea; Thomaschke, Roland; Janczyk, Markus

    2012-01-01

    Human actions are guided either by endogenous action plans or by external stimuli in the environment. These two types of action control seem to be mediated by neurophysiologically and functionally distinct systems that interfere if an endogenously planned action suddenly has to be performed in response to an exogenous stimulus. In this case, the…

  9. Explaining Cigarette Smoking: An Endogenous-Exogenous Analysis.

    Science.gov (United States)

    McKillip, Jack

    Kruglanski's endogenous-exogenous partition, when applied to reasons given by smokers for smoking cigarettes, distinguishes two types of actions: (1) endogenous reasons implying that the behavior of consuming the cigarette is the goal of the action and the actor is positive toward the behavior, and (2) exogenous reasons implying that the behavior…

  10. Optimized endogenous post-stratification in forest inventories

    Science.gov (United States)

    Paul L. Patterson

    2012-01-01

    An example of endogenous post-stratification is the use of remote sensing data with a sample of ground data to build a logistic regression model to predict the probability that a plot is forested and using the predicted probabilities to form categories for post-stratification. An optimized endogenous post-stratified estimator of the proportion of forest has been...

  11. Role of endogenous substances in enhancing radioresistance background

    International Nuclear Information System (INIS)

    Goncharenko, E.N.; Gorskaya, T.G.; Graevskaya, E.Eh.; Kozlova, M.A.

    1979-01-01

    Presumable sources of endogenous were studied amines in radiosensitive tissues under the effect of radioprotective agents were studied. The data obtained support the idea that mast cells of rats, having large deposits of biogenous amines, might be one of the reserves contributing to mobilization of endogeneous protective resources of the organism treated with radioprotective agents

  12. The Endogenous-Exogenous Partition in Attribution Theory

    Science.gov (United States)

    Kruglanski, Arie W.

    1975-01-01

    Within lay explanation of actions, several significant inferences are assumed to follow from the partition between endogenous and exogenous attributions. An endogenous action is judged to constitute an end in itself; an exogenous action is judged to serve as a means to some further end. (Editor/RK)

  13. Interaction between endogenous and exogenous orienting in crossmodal attention.

    Science.gov (United States)

    Chen, Xiaoxi; Chen, Qi; Gao, Dingguo; Yue, Zhenzhu

    2012-08-01

    Using a cue-target paradigm, we investigated the interaction between endogenous and exogenous orienting in cross-modal attention. A peripheral (exogenous) cue was presented after a central (endogenous) cue with a variable time interval. The endogenous and exogenous cues were presented in one sensory modality (auditory in Experiment 1 and visual in Experiment 2) whereas the target was presented in another modality. Both experiments showed a significant endogenous cuing effect (longer reaction times in the invalid condition than in the valid condition). However, exogenous cuing produced a facilitatory effect in both experiments in response to the target when endogenous cuing was valid, but it elicited a facilitatory effect in Experiment 1 and an inhibitory effect in Experiment 2 when endogenous cuing was invalid. These findings indicate that endogenous and exogenous cuing can co-operate in orienting attention to the crossmodal target. Moreover, the interaction between endogenous and exogenous orienting of attention is modulated by the modality between the cue and the target. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.

  14. Endogene opioider og deres terapeutiske anvendelse i smertebehandling

    DEFF Research Database (Denmark)

    Juul, A; Pedersen, A T

    1990-01-01

    Cancer patients with chronic pain and obstetric patients have participated in clinical trials of the analgesic effects of endogenous opioids. It is possible to achieve adequate relief of pain in these patients following epidural or intrathecal administration of endogenous opioids. Further investi...

  15. On the Endogeneity of the Mean-Variance Efficient Frontier.

    Science.gov (United States)

    Somerville, R. A.; O'Connell, Paul G. J.

    2002-01-01

    Explains that the endogeneity of the efficient frontier in the mean-variance model of portfolio selection is commonly obscured in portfolio selection literature and in widely used textbooks. Demonstrates endogeneity and discusses the impact of parameter changes on the mean-variance efficient frontier and on the beta coefficients of individual…

  16. Primary thyroid disorders in endogenous Cushing's syndrome.

    Science.gov (United States)

    Niepomniszcze, Hugo; Pitoia, Fabian; Katz, Silvia B; Chervin, Raul; Bruno, Oscar D

    2002-09-01

    To study the prevalence of primary thyroid disorders in patients who underwent endogenous hypercortisolism. Retrospective evaluation of 59 patients with Cushing's syndrome (CS) who had, at least, a record of thyroid palpation by expert endocrinologists and basal measurements of TSH by second generation assays. When available, tri-iodothyronine and thyroxine serum levels, TRH-TSH tests and anti-thyroid antibodies were also analyzed. There were two age- and gender-matched control groups. The 'goiter control group' comprised 118 healthy subjects who underwent thyroid palpation. The 'antibody control group' was composed of 40 individuals who attended the blood bank of our hospital. Antibodies against thyroperoxidase and measurements of TSH were analyzed in their blood samples. Available files of 83 CS patients admitted to our endocrine unit from 1985 to 1998 were examined. Fifty-nine patients (52 women and 7 men) with a mean age of 36.2 years (range 14-61 years) met the above requirements. Diagnosis of hypercortisolism had been established by a standard 1-mg overnight dexamethasone suppression test and urinary free cortisol (UFC). Etiological diagnosis involved dynamic testing, measurements of ACTH levels and imaging techniques. After treatment, all but one of the patients were cured or controlled of their hypercortisolism. This was established by the finding of subnormal serum cortisol concentrations and/or subnormal 24-h UFC levels. Primary thyroid disorders were defined by the presence of one or more of the following diagnostic criteria: (i) goiter, (ii) positive anti-thyroid antibodies and/or (iii) primary thyroid function abnormalities. Eighteen (30.5%) patients had goiter (diffuse in 78% and nodular in 22%), 14 (23.7%) had primary subclinical hypothyroidism and 5 (8.4%) had hyperthyroidism. In 41 patients evaluated for antithyroid antibodies, it was found that 23 (56.1%) had positive titers. In a group of patients in which thyroid autoantibodies were measured

  17. Monocular channels have a functional role in endogenous orienting.

    Science.gov (United States)

    Saban, William; Sekely, Liora; Klein, Raymond M; Gabay, Shai

    2018-03-01

    The literature has long emphasized the role of higher cortical structures in endogenous orienting. Based on evolutionary explanation and previous data, we explored the possibility that lower monocular channels may also have a functional role in endogenous orienting of attention. Sensitive behavioral manipulation was used to probe the contribution of monocularly segregated regions in a simple cue - target detection task. A central spatially informative cue, and its ensuing target, were presented to the same or different eyes at varying cue-target intervals. Results indicated that the onset of endogenous orienting was apparent earlier when the cue and target were presented to the same eye. The data provides converging evidence for the notion that endogenous facilitation is modulated by monocular portions of the visual stream. This, in turn, suggests that higher cortical mechanisms are not exclusively responsible for endogenous orienting, and that a dynamic interaction between higher and lower neural levels, might be involved. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Endogenous retroviruses mobilized during friend murine leukemia virus infection.

    Science.gov (United States)

    Boi, Stefano; Rosenke, Kyle; Hansen, Ethan; Hendrick, Duncan; Malik, Frank; Evans, Leonard H

    2016-12-01

    We have demonstrated in a mouse model that infection with a retrovirus can lead not only to the generation of recombinants between exogenous and endogenous gammaretrovirus, but also to the mobilization of endogenous proviruses by pseudotyping entire polytropic proviral transcripts and facilitating their infectious spread to new cells. However, the frequency of this occurrence, the kinetics, and the identity of mobilized endogenous proviruses was unclear. Here we find that these mobilized transcripts are detected after only one day of infection. They predominate over recombinant polytropic viruses early in infection, persist throughout the course of disease and are comprised of multiple different polytropic proviruses. Other endogenous retroviral elements such as intracisternal A particles (IAPs) were not detected. The integration of the endogenous transcripts into new cells could result in loss of transcriptional control and elevated expression which may facilitate pathogenesis, perhaps by contributing to the generation of polytropic recombinant viruses. Published by Elsevier Inc.

  19. Ascorbic acid protects lipids in human plasma and low-density lipoprotein against oxidative damage

    Energy Technology Data Exchange (ETDEWEB)

    Frei, B. (Department of Nutrition, Harvard School of Public Health, Boston, MA (Unites States))

    1991-12-01

    The authors exposed human blood plasma and low-density lipoprotein (LDL) to many different oxidative challenges and followed the temporal consumption of endogenous antioxidants in relation to the initiation of oxidative damage. Under all types of oxidizing conditions, ascorbic acid completely protects lipids in plasma and LDL against detectable peroxidative damage as assessed by a specific and highly sensitive assay for lipid peroxidation. Ascorbic acid proved to be superior to the other water-soluble plasma antioxidants bilirubin, uric acid, and protein thiols as well as to the lipoprotein-associated antioxidants alpha-tocopherol, ubiquinol-10, lycopene, and beta-carotene. Although these antioxidants can lower the rate of detectable lipid peroxidation, they are not able to prevent its initiation. Only ascorbic acid is reactive enough to effectively intercept oxidants in the aqueous phase before they can attack and cause detectable oxidative damage to lipids.

  20. iNKT Cells and Their potential Lipid Ligands during Viral Infection

    Directory of Open Access Journals (Sweden)

    Anunya eOpasawatchai

    2015-07-01

    Full Text Available Invariant natural killer T (iNKT cells are a unique population of lipid reactive CD1d restricted innate-like T lymphocytes. Despite being a minor population, they serve as an early source of cytokines and promote immunological crosstalk thus bridging innate and adaptive immunity. Diseases ranging from allergy, autoimmunity, and cancer as well as infectious diseases, including viral infection, have been reported to be influenced by iNKT cells. However, it remains unclear how iNKT cells are activated during viral infection, as virus derived lipid antigens have not been reported. Cytokines may activate iNKT cells during infections from influenza and murine cytomegalovirus (MCMV, although CD1d dependent activation is evident in other viral infections. Several viruses, such as dengue virus (DENV, induce CD1d upregulation which correlates with iNKT cell activation. In contrast, Herpes simplex virus type 1 (HSV-1, Human immunodeficiency virus (HIV, Epstein-Barr virus (EBV and Human papiloma virus (HPV promote CD1d downregulation as a strategy to evade iNKT cell recognition. These observations suggest the participation of a CD1d-dependent process in the activation of iNKT cells in response to viral infection. Endogenous lipid ligands, including phospholipids as well as glycosphingolipids, such as glucosylceramide have been proposed to mediate iNKT cell activation. Pro-inflammatory signals produced during viral infection may stimulate iNKT cells through enhanced CD1d dependent endogenous lipid presentation. Furthermore, viral infection may alter lipid composition and inhibit endogenous lipid degradation. Recent advances in this field are reviewed.

  1. Endogenous hepadnaviruses, bornaviruses and circoviruses in snakes.

    Science.gov (United States)

    Gilbert, C; Meik, J M; Dashevsky, D; Card, D C; Castoe, T A; Schaack, S

    2014-09-22

    We report the discovery of endogenous viral elements (EVEs) from Hepadnaviridae, Bornaviridae and Circoviridae in the speckled rattlesnake, Crotalus mitchellii, the first viperid snake for which a draft whole genome sequence assembly is available. Analysis of the draft assembly reveals genome fragments from the three virus families were inserted into the genome of this snake over the past 50 Myr. Cross-species PCR screening of orthologous loci and computational scanning of the python and king cobra genomes reveals that circoviruses integrated most recently (within the last approx. 10 Myr), whereas bornaviruses and hepadnaviruses integrated at least approximately 13 and approximately 50 Ma, respectively. This is, to our knowledge, the first report of circo-, borna- and hepadnaviruses in snakes and the first characterization of non-retroviral EVEs in non-avian reptiles. Our study provides a window into the historical dynamics of viruses in these host lineages and shows that their evolution involved multiple host-switches between mammals and reptiles. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  2. Endogenous T-Cell Therapy: Clinical Experience.

    Science.gov (United States)

    Yee, Cassian; Lizee, Greg; Schueneman, Aaron J

    2015-01-01

    Adoptive cellular therapy represents a robust means of augmenting the tumor-reactive effector population in patients with cancer by adoptive transfer of ex vivo expanded T cells. Three approaches have been developed to achieve this goal: the use of tumor-infiltrating lymphocytes or tumor-infiltrating lymphocytess extracted from patient biopsy material; the redirected engineering of lymphocytes using vectors expressing a chimeric antigen receptor and T-cell receptor; and third, the isolation and expansion of often low-frequency endogenous T cells (ETCs) reactive to tumor antigens from the peripheral blood of patients. This last form of adoptive transfer of T cells, known as ETC therapy, requires specialized methods to isolate and expand from peripheral blood the very low-frequency tumor-reactive T cells, methods that have been developed over the last 2 decades, to the point where such an approach may be broadly applicable not only for the treatment of melanoma but also for that of other solid tumor malignancies. One compelling feature of ETC is the ability to rapidly deploy clinical trials following identification of a tumor-associated target epitope, a feature that may be exploited to develop personalized antigen-specific T-cell therapy for patients with almost any solid tumor. With a well-validated antigen discovery pipeline in place, clinical studies combining ETC with agents that modulate the immune microenvironment can be developed that will transform ETC into a feasible treatment modality.

  3. Endogenous retroviral promoter exaptation in human cancer

    Directory of Open Access Journals (Sweden)

    Artem Babaian

    2016-12-01

    Full Text Available Abstract Cancer arises from a series of genetic and epigenetic changes, which result in abnormal expression or mutational activation of oncogenes, as well as suppression/inactivation of tumor suppressor genes. Aberrant expression of coding genes or long non-coding RNAs (lncRNAs with oncogenic properties can be caused by translocations, gene amplifications, point mutations or other less characterized mechanisms. One such mechanism is the inappropriate usage of normally dormant, tissue-restricted or cryptic enhancers or promoters that serve to drive oncogenic gene expression. Dispersed across the human genome, endogenous retroviruses (ERVs provide an enormous reservoir of autonomous gene regulatory modules, some of which have been co-opted by the host during evolution to play important roles in normal regulation of genes and gene networks. This review focuses on the “dark side” of such ERV regulatory capacity. Specifically, we discuss a growing number of examples of normally dormant or epigenetically repressed ERVs that have been harnessed to drive oncogenes in human cancer, a process we term onco-exaptation, and we propose potential mechanisms that may underlie this phenomenon.

  4. Role of endogenous thiols in protection

    Science.gov (United States)

    Vos, O.

    Aminothiols represent the most important group of radioprotective compounds. The most effective compounds administered at an optimal dose and time before irradiation are able to provide a protection in mice with a dose reduction factor (DRF) of about 2-2.5. The working mechanism can partly be explained as a scavenging process of radicals induced in water and partly as a chemical repair process of injured DNA. The endogenous aminothiol which has far-out the highest intracellular concentration is glutathione (GSH). The importance of intracellular GSH in determining cellular radiosensitivity has been shown by irradiating cells that had very low GSH levels. Such cells appear to have a high radiosensitivity, especially in hypoxic conditions. On the other hand, it has been demonstrated that induction of a high GSH level (100-200% above the normal level) provides only a small protection. In vitro experiments with DNA indicate that thiols with a high positive charge condense in the vicinity of DNA and are effective protectors, whereas thiols with a negative charge are kep away from it and are poor protectors. In comparison with the most effective exogenous aminothiols like cysteamine and WR1065, GSH is not an effective radioprotector. Putative explanations for this relatively poor protective ability of GSH are presented.

  5. Endogenous Retroviruses: With Us and Against Us

    Science.gov (United States)

    Meyer, Thomas J.; Rosenkrantz, Jimi L.; Carbone, Lucia; Chavez, Shawn L.

    2017-04-01

    Mammalian genomes are scattered with thousands of copies of endogenous retroviruses (ERVs), mobile genetic elements that are relics of ancient retroviral infections. After inserting copies into the germ line of a host, most ERVs accumulate mutations that prevent the normal assembly of infectious viral particles, becoming trapped in host genomes and unable to leave to infect other cells. While most copies of ERVs are inactive, some are transcribed and encode the proteins needed to generate new insertions at novel loci. In some cases, old copies are removed via recombination and other mechanisms. This creates a shifting landscape of ERV copies within host genomes. New insertions can disrupt normal expression of nearby genes via directly inserting into key regulatory elements or by containing regulatory motifs within their sequences. Further, the transcriptional silencing of ERVs via epigenetic modification may result in changes to the epigenetic regulation of adjacent genes. In these ways, ERVs can be potent sources of regulatory disruption as well as genetic innovation. Here, we provide a brief review of the association between ERVs and gene expression, especially as observed in pre-implantation development and placentation. Moreover, we will describe the roles ERVs may play in somatic tissues, mostly in the context of human disease, including cancer, neurodegenerative disorders, and schizophrenia. Lastly, we discuss the recent discovery that some ERVs may have been pressed into the service of their host genomes to aid in the innate immune response to exogenous viral infections.

  6. Enterococcus faecalis Endogenous Endophthalmitis from Valvular Endocarditis

    Directory of Open Access Journals (Sweden)

    Sidnei Barge

    2013-01-01

    Full Text Available We report a case of a 74-year-old female, with a mitral heart valve, who presented with pain and blurred vision in the right eye for 2 days. Her visual acuity was light perception (LP in the right eye and 20/40 in the left eye. Slit lamp examination showed corneal edema and hypopyon, and a view of the right fundus was impossible. Echography showed vitreous condensation. One day after presentation, the patient developed acute lung edema requiring hospitalization, so she was not submitted to vitreous tap and intravitreal treatment. The cardiac and systemic evaluations revealed a mitral endocarditis secondary to Enterococcus faecalis. The patient improved systemically with treatment with gentamicin, vancomycin, and linezolid. Her visual acuity remained as no LP, and her intraocular pressure (IOP has been controlled with brimonidine bid despite developing a total cataract with 360° posterior synechia. A cardiac source for endogenous endophthalmitis should be considered in the presence of a prosthetic cardiac valve. The treatment and followup must be made in cooperation with a cardiologist specialist, but the ophthalmologist can play a key role in the diagnosis.

  7. Omega-3 fatty acids, lipids, and apoE lipidation in Alzheimer's disease: a rationale for multi-nutrient dementia prevention.

    Science.gov (United States)

    Grimm, Marcus O W; Michaelson, Daniel M; Hartmann, Tobias

    2017-11-01

    In the last decade, it has become obvious that Alzheimer's disease (AD) is closely linked to changes in lipids or lipid metabolism. One of the main pathological hallmarks of AD is amyloid-β (Aβ) deposition. Aβ is derived from sequential proteolytic processing of the amyloid precursor protein (APP). Interestingly, both, the APP and all APP secretases are transmembrane proteins that cleave APP close to and in the lipid bilayer. Moreover, apoE4 has been identified as the most prevalent genetic risk factor for AD. ApoE is the main lipoprotein in the brain, which has an abundant role in the transport of lipids and brain lipid metabolism. Several lipidomic approaches revealed changes in the lipid levels of cerebrospinal fluid or in post mortem AD brains. Here, we review the impact of apoE and lipids in AD, focusing on the major brain lipid classes, sphingomyelin, plasmalogens, gangliosides, sulfatides, DHA, and EPA, as well as on lipid signaling molecules, like ceramide and sphingosine-1-phosphate. As nutritional approaches showed limited beneficial effects in clinical studies, the opportunities of combining different supplements in multi-nutritional approaches are discussed and summarized. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  8. Lipid reserves of red mullet (Mullus barbatus during pre-spawning in the northwestern Mediterranean

    Directory of Open Access Journals (Sweden)

    Josep Lloret

    2007-06-01

    Full Text Available Lipid reserves are a particularly important attribute of fishes because they have a large influence on growth, reproduction and survival. This study analyses the lipid content of red mullet (Mullus barbatus pre-spawners in three different areas of the northwestern Mediterranean in relation to trawling activities and river runoff. The muscle lipid was considered as an indicator of the somatic condition of individuals whilst the gonad lipid was used as a proxy of the energy invested in reproduction. The results show that fish with the highest muscle lipid levels inhabited the area where fishing impact was lowest. Since the abundance and biomass of polychaetes, which represent the main food source for red mullet, were found to be lower in trawled zones than in unfished ones, we suggest that differences in the muscle lipid levels between areas might be attributed to variation in prey abundance in relation to fishing impact. However, no impact of river runoff on lipid reserves of red mullet was observed. The results also show that muscle and gonad lipid reserves are not related to each other during pre-spawning.

  9. Liver lipid molecules induce PEPCK-C gene transcription and attenuate insulin action

    International Nuclear Information System (INIS)

    Chen Guoxun

    2007-01-01

    Cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C) plays key roles in gluconeogenesis, glyceroneogenesis, and cataplerosis. Experiments were designed to examine the effects of endogenous lipid molecules from rat livers on the expression of PEPCK-C gene in primary rat hepatocytes. The lipid extracts prepared from livers of Zucker fatty, lean, and Wistar rats induced the expression levels of PEPCK-C transcripts. Insulin-mediated reduction of PEPCK-C gene expression was attenuated by the same treatment. The lipid extracts induced the relative luciferase activity of reporter gene constructs that contain a 2.2-kb 5' promoter fragment of PEPCK-C gene, but not the construct that contains only the 3' untranslated region (UTR) of its mRNA. The estimated half life of PEPCK-C transcripts in the presence of the lipid extract is the same as that in the absence of it. My results demonstrate for the first time that endogenous lipid molecules induce PEPCK-C gene transcription and attenuate insulin action in liver

  10. Measurement of the incorporation of orally administered arachidonic acid into tissue lipids

    International Nuclear Information System (INIS)

    Kulmacz, R.J.; Sivarajan, M.; Lands, W.E.

    1986-01-01

    The applicability of a stable isotope method to monitor the mixing of dietary arachidonic acid with endogenous arachidonic acid in tissue lipids was evaluated. Rats were fed octadeuterated arachidonic acid during a 20-day period, and the entry of the dietary acid into lipid esters of various tissues was examined by gas chromatography-mass spectrometric (GC-MS) analysis of their fatty acids. The rats were maintained on a fat-free diet from weaning until 63 days old to enhance the ratio of the dietary acid to endogenous arachidonate. Three separate forms of eicosatetraenoic acid in the tissue lipids could be distinguished by GC-MS: octadeuterated arachidonic acid (recent dietary origin), unlabeled arachidonic acid (maternal origin) and unlabeled 4,7,10,13-eicosatetraenoic acid (originating from palmitoleic acid). The total eicosatetraenoic acid in the tissue lipids contained about 90% arachidonate from recent dietary origin in lung, kidney, heart and fat, 70% in muscle and liver and 27% in brain. The n-7 isomer of eicosatetraenoic acid was estimated to make up 6% or less of the total eicosatetraenoic acid in lung, kidney, brain, muscle and heart tissue lipids, but it comprised around 15% of the total eicosatetraenoic acid in liver. The unlabeled arachidonic acid of maternal origin thus comprised only about 10% of the eicosatetraenoic acid in all tissues examined except muscle and brain, where it was 24% and 70% of the eicosatetraenoic acid, respectively

  11. Significant biases affecting abundance determinations

    Science.gov (United States)

    Wesson, Roger

    2015-08-01

    I have developed two highly efficient codes to automate analyses of emission line nebulae. The tools place particular emphasis on the propagation of uncertainties. The first tool, ALFA, uses a genetic algorithm to rapidly optimise the parameters of gaussian fits to line profiles. It can fit emission line spectra of arbitrary resolution, wavelength range and depth, with no user input at all. It is well suited to highly multiplexed spectroscopy such as that now being carried out with instruments such as MUSE at the VLT. The second tool, NEAT, carries out a full analysis of emission line fluxes, robustly propagating uncertainties using a Monte Carlo technique.Using these tools, I have found that considerable biases can be introduced into abundance determinations if the uncertainty distribution of emission lines is not well characterised. For weak lines, normally distributed uncertainties are generally assumed, though it is incorrect to do so, and significant biases can result. I discuss observational evidence of these biases. The two new codes contain routines to correctly characterise the probability distributions, giving more reliable results in analyses of emission line nebulae.

  12. Differential distribution of lipids in epidermis, gastrodermis and hosted Symbiodinium in the sea anemone Anemonia viridis.

    Science.gov (United States)

    Revel, Johana; Massi, Lionel; Mehiri, Mohamed; Boutoute, Marc; Mayzaud, Patrick; Capron, Laure; Sabourault, Cécile

    2016-01-01

    Cnidarian-dinoflagellate symbiosis mainly relies on nutrient recycling, thus providing both partners with a competitive advantage in nutrient-poor waters. Essential processes related to lipid metabolism can be influenced by various factors, including hyperthermal stress. This can affect the lipid content and distribution in both partners, while contributing to symbiosis disruption and bleaching. In order to gain further insight into the role and distribution of lipids in the cnidarian metabolism, we investigated the lipid composition of the sea anemone Anemonia viridis and its photosynthetic dinoflagellate endosymbionts (Symbiodinium). We compared the lipid content and fatty acid profiles of the host cellular layers, non-symbiotic epidermal and symbiont-containing gastrodermal cells, and those of Symbiodinium, in a mass spectrometry-based assessment. Lipids were more concentrated in Symbiodinium cells, and the lipid class distribution was dominated by polar lipids in all tissues. The fatty acid distribution between host cell layers and Symbiodinium cells suggested potential lipid transfers between the partners. The lipid composition and distribution was modified during short-term hyperthermal stress, mainly in Symbiodinium cells and gastrodermis. Exposure to elevated temperature rapidly caused a decrease in polar lipid C18 unsaturated fatty acids and a strong and rapid decrease in the abundance of polar lipid fatty acids relative to sterols. These lipid indicators could therefore be used as sensitive biomarkers to assess the physiology of symbiotic cnidarians, especially the effect of thermal stress at the onset of cnidarian bleaching. Overall, the findings of this study provide some insight on key lipids that may regulate maintenance of the symbiotic interaction. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Extended synaptotagmins are Ca2+-dependent lipid transfer proteins at membrane contact sites.

    Science.gov (United States)

    Yu, Haijia; Liu, Yinghui; Gulbranson, Daniel R; Paine, Alex; Rathore, Shailendra S; Shen, Jingshi

    2016-04-19

    Organelles are in constant communication with each other through exchange of proteins (mediated by trafficking vesicles) and lipids [mediated by both trafficking vesicles and lipid transfer proteins (LTPs)]. It has long been known that vesicle trafficking can be tightly regulated by the second messenger Ca(2+), allowing membrane protein transport to be adjusted according to physiological demands. However, it remains unclear whether LTP-mediated lipid transport can also be regulated by Ca(2+) In this work, we show that extended synaptotagmins (E-Syts), poorly understood membrane proteins at endoplasmic reticulum-plasma membrane contact sites, are Ca(2+)-dependent LTPs. Using both recombinant and endogenous mammalian proteins, we discovered that E-Syts transfer glycerophospholipids between membrane bilayers in the presence of Ca(2+) E-Syts use their lipid-accommodating synaptotagmin-like mitochondrial lipid binding protein (SMP) domains to transfer lipids. However, the SMP domains themselves cannot transport lipids unless the two membranes are tightly tethered by Ca(2+)-bound C2 domains. Strikingly, the Ca(2+)-regulated lipid transfer activity of E-Syts was fully recapitulated when the SMP domain was fused to the cytosolic domain of synaptotagmin-1, the Ca(2+)sensor in synaptic vesicle fusion, indicating that a common mechanism of membrane tethering governs the Ca(2+)regulation of lipid transfer and vesicle fusion. Finally, we showed that microsomal vesicles isolated from mammalian cells contained robust Ca(2+)-dependent lipid transfer activities, which were mediated by E-Syts. These findings established E-Syts as a novel class of LTPs and showed that LTP-mediated lipid trafficking, like vesicular transport, can be subject to tight Ca(2+)regulation.

  14. Thermodynamic clarification of interaction between antiseptic compounds and lipids consisting of stratum corneum

    International Nuclear Information System (INIS)

    Aki, Hatsumi; Kawasaki, Yuhsuke

    2004-01-01

    The interactions of antiseptic compounds with quaternary ammonium, such as benzalkonium chloride (BC), benzethonium chloride (BZC), dodecyldiaminoethyl-glycine hydrochloride (AEG), and chlorhexidine gluconate (CHG), with components of the stratum corneum were investigated by isothermal titration calorimetry at pH 7.5 and 25 deg. C. The different mechanisms for their permeation to stratum corneum were clarified. Cationic surfactants of BC and BZC bound to cholesterol and cholesterol sulfate with high affinity (10 5 -10 6 M -1 ) to extract endogenous cholesterol and its derivatives from the stratum corneum and penetrated via an intercellular route. CHG also bound to cholesterol and accumulated in the stratum corneum without removing endogenous cholesterol. On the other hand, an amphoteric surfactant of AEG seemed to be incorporated into the lipid bilayer and bound to ceramide with its polar end close to the lipid polar heads by hydrophobic interaction

  15. Thermodynamic clarification of interaction between antiseptic compounds and lipids consisting of stratum corneum

    Energy Technology Data Exchange (ETDEWEB)

    Aki, Hatsumi; Kawasaki, Yuhsuke

    2004-06-24

    The interactions of antiseptic compounds with quaternary ammonium, such as benzalkonium chloride (BC), benzethonium chloride (BZC), dodecyldiaminoethyl-glycine hydrochloride (AEG), and chlorhexidine gluconate (CHG), with components of the stratum corneum were investigated by isothermal titration calorimetry at pH 7.5 and 25 deg. C. The different mechanisms for their permeation to stratum corneum were clarified. Cationic surfactants of BC and BZC bound to cholesterol and cholesterol sulfate with high affinity (10{sup 5}-10{sup 6} M{sup -1}) to extract endogenous cholesterol and its derivatives from the stratum corneum and penetrated via an intercellular route. CHG also bound to cholesterol and accumulated in the stratum corneum without removing endogenous cholesterol. On the other hand, an amphoteric surfactant of AEG seemed to be incorporated into the lipid bilayer and bound to ceramide with its polar end close to the lipid polar heads by hydrophobic interaction.

  16. Endogenous versus exogenous shocks in systems with memory

    Science.gov (United States)

    Sornette, D.; Helmstetter, A.

    2003-02-01

    Systems with long-range persistence and memory are shown to exhibit different precursory as well as recovery patterns in response to shocks of exogenous versus endogenous origins. By endogenous, we envision either fluctuations resulting from an underlying chaotic dynamics or from a stochastic forcing origin which may be external or be an effective coarse-grained description of the microscopic fluctuations. In this scenario, endogenous shocks result from a kind of constructive interference of accumulated fluctuations whose impacts survive longer than the large shocks themselves. As a consequence, the recovery after an endogenous shock is in general slower at early times and can be at long times either slower or faster than after an exogenous perturbation. This offers the tantalizing possibility of distinguishing between an endogenous versus exogenous cause of a given shock, even when there is no “smoking gun”. This could help in investigating the exogenous versus self-organized origins in problems such as the causes of major biological extinctions, of change of weather regimes and of the climate, in tracing the source of social upheaval and wars, and so on. Sornette et al., Volatility fingerprints of large stocks: endogenous versus exogenous, cond-mat/0204626 has already shown how this concept can be applied concretely to differentiate the effects on financial markets of the 11 September 2001 attack or of the coup against Gorbachev on 19 August 1991 (exogenous) from financial crashes such as October 1987 (endogenous).

  17. Hydrocarbon Reserves: Abundance or Scarcity

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may impact on the growth

  18. Hydrocarbon Reserves: Abundance or Scarcity

    International Nuclear Information System (INIS)

    2005-01-01

    IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may impact on the growth

  19. Hydrocarbon Reserves: Abundance or Scarcity

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may

  20. Endogenous synthesis of corticosteroids in the hippocampus.

    Directory of Open Access Journals (Sweden)

    Shimpei Higo

    Full Text Available BACKGROUND: Brain synthesis of steroids including sex-steroids is attracting much attention. The endogenous synthesis of corticosteroids in the hippocampus, however, has been doubted because of the inability to detect deoxycorticosterone (DOC synthase, cytochrome P450(c21. METHODOLOGY/PRINCIPAL FINDINGS: The expression of P450(c21 was demonstrated using mRNA analysis and immmunogold electron microscopic analysis in the adult male rat hippocampus. DOC production from progesterone (PROG was demonstrated by metabolism analysis of (3H-steroids. All the enzymes required for corticosteroid synthesis including P450(c21, P450(2D4, P450(11β1 and 3β-hydroxysteroid dehydrogenase (3β-HSD were localized in the hippocampal principal neurons as shown via in situ hybridization and immunoelectron microscopic analysis. Accurate corticosteroid concentrations in rat hippocampus were determined by liquid chromatography-tandem mass spectrometry. In adrenalectomized rats, net hippocampus-synthesized corticosterone (CORT and DOC were determined to 6.9 and 5.8 nM, respectively. Enhanced spinogenesis was observed in the hippocampus following application of low nanomolar (10 nM doses of CORT for 1 h. CONCLUSIONS/SIGNIFICANCE: These results imply the complete pathway of corticosteroid synthesis of 'pregnenolone →PROG→DOC→CORT' in the hippocampal neurons. Both P450(c21 and P450(2D4 can catalyze conversion of PROG to DOC. The low nanomolar level of CORT synthesized in hippocampal neurons may play a role in modulation of synaptic plasticity, in contrast to the stress effects by micromolar CORT from adrenal glands.

  1. Manager's effort and endogenous economic discrimination

    Directory of Open Access Journals (Sweden)

    Jaime Orrillo

    2004-09-01

    Full Text Available Assume a labor supply consisting of two types of workers, 1 and 2. Both workers are equally productive and exhibit supply functions with the same elasticity. We consider a firm (entrepreneur or shareholders that is competitive in the output market and monopsonistic in input markets. The firm uses the services of a manager who has a high human capital and whose wage is given by the market. It is supposed that the manager does not like to work with one type of worker, say type 1. If we allow the manager's effort to be an additional input without any extra (in addition to his salary cost for the firm, then the firm's pricing decision will be different for both workers. That is, there will be a wage differential and therefore endogenous economic discrimination2 in the labor markets.Vamos assumir que a oferta de trabalho consiste de dois tipos de trabalhadores, 1 e 2. Ambos os trabalhadores são igualmente produtivos e exibem funções de oferta com a mesma elasticidade. Consideramos uma firma (empresário ou acionistas, a qual é competitiva no mercado de produtos e monopsonista nos mercados de insumos. A firma usa os serviços de um gerente quem tem um alto capital humano e cujo salário é dado pelo mercado. Suponhamos que o gerente não gosta de trabalhar com um tipo de trabalhador, digamos o tipo 1. Se permitirmos que o esforço do gerente seja um insumo adicional sem nenhum custo extra (além de seu salário, a decisão de salários será diferente para ambos os trabalhadores. Isto é, haverá um diferencial de salários e, em conseqüência, uma discriminação econômica1 endógena nos mercados de trabalho.

  2. In vivo Anomalous Diffusion and Weak Ergodicity Breaking of Lipid Granules

    DEFF Research Database (Denmark)

    Jeon, J.-H.; Tejedor, V.; Burov, S.

    2011-01-01

    Combining extensive single particle tracking microscopy data of endogenous lipid granules in living fission yeast cells with analytical results we show evidence for anomalous diffusion and weak ergodicity breaking. Namely we demonstrate that at short times the granules perform subdiffusion...... according to the laws of continuous time random walk theory. The associated violation of ergodicity leads to a characteristic turnover between two scaling regimes of the time averaged mean squared displacement. At longer times the granule motion is consistent with fractional Brownian motion....

  3. Demonstration of endogenous imipramine like material in rat brain

    International Nuclear Information System (INIS)

    Rehavi, M.; Ventura, I.; Sarne, Y.

    1985-01-01

    The extraction and partial purification of an endogenous imipramine-like material from rat brain is described. The endogenous factor obtained after gel filtration and silica chromatography inhibits [ 3 H] imipramine specific binding and mimics the inhibitory effect of imipramine on [ 3 H] serotonin uptake in both brain and platelet preparations. The effects of the endogenous material are dose-dependent and it inhibits [ 3 H] imipramine binding in a competitive fashion. The factor is unevenly distributed in the brain with high concentration in the hypothalamus and low concentration in the cerebellum

  4. Amplification and chromosomal dispersion of human endogenous retroviral sequences

    International Nuclear Information System (INIS)

    Steele, P.E.; Martin, M.A.; Rabson, A.B.; Bryan, T.; O'Brien, S.J.

    1986-01-01

    Endogenous retroviral sequences have undergone amplification events involving both viral and flanking cellular sequences. The authors cloned members of an amplified family of full-length endogenous retroviral sequences. Genomic blotting, employing a flanking cellular DNA probe derived from a member of this family, revealed a similar array of reactive bands in both humans and chimpanzees, indicating that an amplification event involving retroviral and associated cellular DNA sequences occurred before the evolutionary separation of these two primates. Southern analyses of restricted somatic cell hybrid DNA preparations suggested that endogenous retroviral segments are widely dispersed in the human genome and that amplification and dispersion events may be linked

  5. Strategies for the photo-control of endogenous protein activity.

    Science.gov (United States)

    Brechun, Katherine E; Arndt, Katja M; Woolley, G Andrew

    2017-08-01

    Photo-controlled or 'optogenetic' effectors interfacing with endogenous protein machinery allow the roles of endogenous proteins to be probed. There are two main approaches being used to develop optogenetic effectors: (i) caging strategies using photo-controlled conformational changes, and (ii) protein relocalization strategies using photo-controlled protein-protein interactions. Numerous specific examples of these approaches have been reported and efforts to develop general methods for photo-control of endogenous proteins are a current focus. The development of improved screening and selection methods for photo-switchable proteins would advance the field. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Polychlorinated biphenyl exposure, diabetes and endogenous hormones: a cross-sectional study in men previously employed at a capacitor manufacturing plant.

    Science.gov (United States)

    Persky, Victoria; Piorkowski, Julie; Turyk, Mary; Freels, Sally; Chatterton, Robert; Dimos, John; Bradlow, H Leon; Chary, Lin Kaatz; Burse, Virlyn; Unterman, Terry; Sepkovic, Daniel W; McCann, Kenneth

    2012-08-29

    Studies have shown associations of diabetes and endogenous hormones with exposure to a wide variety of organochlorines. We have previously reported positive associations of polychlorinated biphenyls (PCBs) and inverse associations of selected steroid hormones with diabetes in postmenopausal women previously employed in a capacitor manufacturing plant. This paper examines associations of PCBs with diabetes and endogenous hormones in 63 men previously employed at the same plant who in 1996 underwent surveys of their exposure and medical history and collection of bloods and urine for measurements of PCBs, lipids, liver function, hematologic markers and endogenous hormones. PCB exposure was positively associated with diabetes and age and inversely associated with thyroid stimulating hormone and triiodothyronine-uptake. History of diabetes was significantly related to total PCBs and all PCB functional groupings, but not to quarters worked and job score, after control for potential confounders. None of the exposures were related to insulin resistance (HOMA-IR) in non-diabetic men. Associations of PCBs with specific endogenous hormones differ in some respects from previous findings in postmenopausal women employed at the capacitor plant. Results from this study, however, do confirm previous reports relating PCB exposure to diabetes and suggest that these associations are not mediated by measured endogenous hormones.

  7. The TULIP superfamily of eukaryotic lipid-binding proteins as a mediator of lipid sensing and transport.

    Science.gov (United States)

    Alva, Vikram; Lupas, Andrei N

    2016-08-01

    lipids endogenous to the cell, and the BPI-like proteins (including the Takeout-like proteins of arthropods), which act on exogenous lipids. This article is part of a Special Issue entitled: The cellular lipid landscape edited by Tim P. Levine and Anant K. Menon. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Unraveling lipid metabolism in lipid-dependent pathogenic Malassezia yeasts

    OpenAIRE

    Celis Ramirez, A.M.

    2017-01-01

    Malassezia yeasts are lipid-dependent fungal species that are common members of the human and animal skin microbiota. The lipid-dependency is a crucial trait in the adaptation process to grow on the skin but also plays a role in their pathogenic life style. Malassezia species can cause several skin infections like dandruff or seborrheic dermatitis but also bloodstream infections. Understanding the lipid metabolism in Malassezia is essential to understand its life style as skin commensal and p...

  9. Studies on changes in fatty acid composition and content of endogenous antioxidants during gamma irradiation of rice seeds

    International Nuclear Information System (INIS)

    Ramarathnam, N.; Osawa, T.; Namiki, M.; Kawakishi, S.

    1989-01-01

    Accelerated aging effects, induced by y irradiation, were investigated on the fatty acid composition of lipids and on the content of endogenous antioxidants of four Indica and four Japonica rice seeds with and without intact hull. While the linoleic acid content of the phospholipids decreased gradually with the increase in irradiation doses, there was a corresponding increase in the linoleic acid content of the free fatty acids. Such changes were drastic, especially in the case of Japonica rice seeds irradiated without intact hull. However, the neutral lipids were found to be resistant to γ irradiation. The α-tocopherol content was found to decrease (markedly) in rice seeds irradiated with or without hull, especially in the Japonica rice seeds. At a dose of 15 kGy only traces of a-tocopherol could be detected in Japonica and Indica rice seeds irradiated with and without intact hull. Oryzanol, a relatively weaker anti-oxidant, was found to be more resistant to oxidative damage than a-tocopherol. At 15 kGy, the oryzanol content ranged from 59 μg to 170 μg/g lipid in rice seeds irradiated with intact hull, while the corresponding value for rice seeds irradiated without hull was 52 μg to 153 μg/g lipid. The overall susceptibility to oxidative damage was less in Indica rice seeds, indicating that the antioxidative defense system offered better protection in overcoming oxidative stress in Indica rice hull than in Japonica rice hull

  10. Polysarcosine-Based Lipids: From Lipopolypeptoid Micelles to Stealth-Like Lipids in Langmuir Blodgett Monolayers

    Directory of Open Access Journals (Sweden)

    Benjamin Weber

    2016-12-01

    Full Text Available Amphiphiles and, in particular, PEGylated lipids or alkyl ethers represent an important class of non-ionic surfactants and have become key ingredients for long-circulating (“stealth” liposomes. While poly-(ethylene glycol (PEG can be considered the gold standard for stealth-like materials, it is known to be neither a bio-based nor biodegradable material. In contrast to PEG, polysarcosine (PSar is based on the endogenous amino acid sarcosine (N-methylated glycine, but has also demonstrated stealth-like properties in vitro, as well as in vivo. In this respect, we report on the synthesis and characterization of polysarcosine based lipids with C14 and C18 hydrocarbon chains and their end group functionalization. Size exclusion chromatography (SEC and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS analysis reveals that lipopeptoids with a degree of polymerization between 10 and 100, dispersity indices around 1.1, and the absence of detectable side products are directly accessible by nucleophilic ring opening polymerization (ROP. The values for the critical micelle concentration for these lipopolymers are between 27 and 1181 mg/L for the ones with C18 hydrocarbon chain or even higher for the C14 counterparts. The lipopolypeptoid based micelles have hydrodynamic diameters between 10 and 25 nm, in which the size scales with the length of the PSar block. In addition, C18PSar50 can be incorporated in 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC monolayers up to a polymer content of 3%. Cyclic compression and expansion of the monolayer showed no significant loss of polymer, indicating a stable monolayer. Therefore, lipopolypeptoids can not only be synthesized under living conditions, but my also provide a platform to substitute PEG-based lipopolymers as excipients and/or in lipid formulations.

  11. The Different Effects Of Endogenous And Exogenous Sex Hormones On Cerebrovascular Diseases

    Directory of Open Access Journals (Sweden)

    Mehdi Shafiee Sabet

    2017-02-01

    Full Text Available Background: A sexual dimorphism is seen in ischemic stroke. Women have lower stroke incidence than men until an advanced age, when the epidemiology of ischemic stroke shifts and incidence rises dramatically in women. This could indicate the role of sex hormones in pathogenesis of cerebrovascular diseases. This Review summarizes the sex differences related to stroke, and the effects of endogenous and exogenAous hormones on the cerebrovasculature of the male and female brain. Methods: We conducted a vast review to analyze possible associations between exposure to endogenous and exogenous female and male steroid hormones and the risks of cerebrovascular diseases. This association is discussed in the context of the effects of sex hormone levels on the progression of atherosclerosis, the vascular tone, and various risk factors including patient's lipid profile, arterial blood pressure and diabetes. Their therapeutic potentials is also reviewed. Results: There is a debate on the role of androgens. A large array of data testifies in favor of a variety of neuroprotective androgen effects in men mostly, but in many cases in women as well. Testosterone supplementation in low to normal levels in hypogonadal men has mostly been shown to benefit the subjects receiving it, but administration in supraphysiological doses however, along with anabolic steroid abuse, seems to adversely affect both the lipid profile and insulin sensitivity in men. Its effects in women have yet to be researched in depth. Due to the lower stroke incidence observed in pre-menopausal women and robust preclinical evidence of neuroprotective and anti-inflammatory properties of estrogen, researchers have focused on the potential benefits of hormones to reduce ischemic brain injury. However, hormone therapy to postmenopausal females increases the risk and severity of ischemic stroke. Moreover, while estrogen treatment is neuroprotective in younger females, estrogen paradoxically increases

  12. UVA-induced reset of hydroxyl radical ultradian rhythm improves temporal lipid production in Chlorella vulgaris.

    Science.gov (United States)

    Balan, Ranjini; Suraishkumar, G K

    2014-01-01

    We report for the first time that the endogenous, pseudo-steady-state, specific intracellular levels of the hydroxyl radical (si-OH) oscillate in an ultradian fashion (model system: the microalga, Chlorella vulgaris), and also characterize the various rhythm parameters. The ultradian rhythm in the endogenous levels of the si-OH occurred with an approximately 6 h period in the daily cycle of light and darkness. Further, we expected that the rhythm reset to a shorter period could rapidly switch the cellular redox states that could favor lipid accumulation. We reset the endogenous rhythm through entrainment with UVA radiation, and generated two new ultradian rhythms with periods of approximately 2.97 h and 3.8 h in the light phase and dark phase, respectively. The reset increased the window of maximum lipid accumulation from 6 h to 12 h concomitant with the onset of the ultradian rhythms. Further, the saturated fatty acid content increased approximately to 80% of total lipid content, corresponding to the peak maxima of the hydroxyl radical levels in the reset rhythm. © 2014 American Institute of Chemical Engineers.

  13. Probing lipid membrane electrostatics

    Science.gov (United States)

    Yang, Yi

    The electrostatic properties of lipid bilayer membranes play a significant role in many biological processes. Atomic force microscopy (AFM) is highly sensitive to membrane surface potential in electrolyte solutions. With fully characterized probe tips, AFM can perform quantitative electrostatic analysis of lipid membranes. Electrostatic interactions between Silicon nitride probes and supported zwitterionic dioleoylphosphatidylcholine (DOPC) bilayer with a variable fraction of anionic dioleoylphosphatidylserine (DOPS) were measured by AFM. Classical Gouy-Chapman theory was used to model the membrane electrostatics. The nonlinear Poisson-Boltzmann equation was numerically solved with finite element method to provide the potential distribution around the AFM tips. Theoretical tip-sample electrostatic interactions were calculated with the surface integral of both Maxwell and osmotic stress tensors on tip surface. The measured forces were interpreted with theoretical forces and the resulting surface charge densities of the membrane surfaces were in quantitative agreement with the Gouy-Chapman-Stern model of membrane charge regulation. It was demonstrated that the AFM can quantitatively detect membrane surface potential at a separation of several screening lengths, and that the AFM probe only perturbs the membrane surface potential by external field created by the internai membrane dipole moment. The analysis yields a dipole moment of 1.5 Debye per lipid with a dipole potential of +275 mV for supported DOPC membranes. This new ability to quantitatively measure the membrane dipole density in a noninvasive manner will be useful in identifying the biological effects of the dipole potential. Finally, heterogeneous model membranes were studied with fluid electric force microscopy (FEFM). Electrostatic mapping was demonstrated with 50 nm resolution. The capabilities of quantitative electrostatic measurement and lateral charge density mapping make AFM a unique and powerful

  14. Lipids and addiction: how sex steroids, prostaglandins, and cannabinoids interact with drugs of abuse.

    Science.gov (United States)

    Leishman, Emma; Kokesh, Kevin J; Bradshaw, Heather B

    2013-04-01

    Lipidomics aims to identify and characterize all endogenous species of lipids and understand their roles in cellular signaling and, ultimately, the functioning of the organism. We are on the cusp of fully understanding the functions of many of the lipid signaling systems that have been identified for decades (e.g., steroids, prostaglandins), whereas our understanding of newer lipid signaling systems (e.g., endocannabinoids, N-acyl amides) still lags considerably behind. With an emphasis on their roles in the neurophysiology of addiction, we will examine three classes of lipids--sex steroids, prostaglandins, and cannabinoids--and how they work synergistically in the neurocircuitry of motivation. We will first give a brief overview of the biosynthesis for each class of lipid and its receptors, and then summarize what is known about the collective roles of the lipids in cocaine and alcohol abuse. This approach provides a novel view of lipid signaling as a class of molecules and their synergistic roles in addiction. © 2013 New York Academy of Sciences.

  15. Texture of lipid bilayer domains

    DEFF Research Database (Denmark)

    Jensen, Uffe Bernchou; Brewer, Jonathan R.; Midtiby, Henrik Skov

    2009-01-01

    We investigate the texture of gel (g) domains in binary lipid membranes composed of the phospholipids DPPC and DOPC. Lateral organization of lipid bilayer membranes is a topic of fundamental and biological importance. Whereas questions related to size and composition of fluid membrane domain...... are well studied, the possibility of texture in gel domains has so far not been examined. When using polarized light for two-photon excitation of the fluorescent lipid probe Laurdan, the emission intensity is highly sensitive to the angle between the polarization and the tilt orientation of lipid acyl...... chains. By imaging the intensity variations as a function of the polarization angle, we map the lateral variations of the lipid tilt within domains. Results reveal that gel domains are composed of subdomains with different lipid tilt directions. We have applied a Fourier decomposition method...

  16. Abundance of introduced species at home predicts abundance away in herbaceous communities

    Science.gov (United States)

    Firn, Jennifer; Moore, Joslin L.; MacDougall, Andrew S.; Borer, Elizabeth T.; Seabloom, Eric W.; HilleRisLambers, Janneke; Harpole, W. Stanley; Cleland, Elsa E.; Brown, Cynthia S.; Knops, Johannes M.H.; Prober, Suzanne M.; Pyke, David A.; Farrell, Kelly A.; Bakker, John D.; O'Halloran, Lydia R.; Adler, Peter B.; Collins, Scott L.; D'Antonio, Carla M.; Crawley, Michael J.; Wolkovich, Elizabeth M.; La Pierre, Kimberly J.; Melbourne, Brett A.; Hautier, Yann; Morgan, John W.; Leakey, Andrew D.B.; Kay, Adam; McCulley, Rebecca; Davies, Kendi F.; Stevens, Carly J.; Chu, Cheng-Jin; Holl, Karen D.; Klein, Julia A.; Fay, Phillip A.; Hagenah, Nicole; Kirkman, Kevin P.; Buckley, Yvonne M.

    2011-01-01

    Many ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countries, revealed that species abundances were similar at native (home) and introduced (away) sites - grass species were generally abundant home and away, while forbs were low in abundance, but more abundant at home. Sites with six or more of these species had similar community abundance hierarchies, suggesting that suites of introduced species are assembling similarly on different continents. Overall, we found that substantial changes to populations are not necessarily a pre-condition for invasion success and that increases in species abundance are unusual. Instead, abundance at home predicts abundance away, a potentially useful additional criterion for biosecurity programmes.

  17. Detection and distribution of endogenous steroids in human stratum corneum

    Directory of Open Access Journals (Sweden)

    Shu-Ping Tseng

    2014-03-01

    Conclusion: The results demonstrate that, with the achievable sensitivity of current analytical technology, physiological concentrations of endogenous steroids, such as hydrocortisone and cortisone, can be found in the SC of some individuals.

  18. Isolating Exogenous and Endogenous Modes of Temporal Attention

    Science.gov (United States)

    Lawrence, Michael A.; Klein, Raymond M.

    2013-01-01

    The differential allocation of information processing resources over time, here termed "temporal attention," may be achieved by relatively automatic "exogenous" or controlled "endogenous" mechanisms. Over 100 years of research has confounded these theoretically distinct dimensions of temporal attention. The current…

  19. Quantitative regularities of development of endogenous infection in irradiated organism

    International Nuclear Information System (INIS)

    Mal'tsev, V.N.

    1979-01-01

    A statistical analysis of data from the literature and the author's own experimental results are reviewed to show the functional relationships between the radiation dose and the development of endogenous infection in irradiated organisms. A direct linear dependence was found between the dose of radiation and the severity of endogenous infection at doses causing death from the ''bone marrow'' syndrome in acute radiation sickness. In case of death from the ''intestinal'' syndrome, an inverse linear dependence can be observed between the radiation dose and the culture yield of microbes from internal organs. In this case, the pathological effect on the organism is due to bacterial endotoxins formed during the disintegration of microbial cells in the organism. Endogenous infection and endotoxinaemia essentially aggravate the progress of acute radiation disease. The importance of endogenous infection for the death of the organism is minimized in irradiation at doses causing death ''under the ray''. (author)

  20. Importance of Endogenous Fibrinolysis in Platelet Thrombus Formation.

    Science.gov (United States)

    Gue, Ying X; Gorog, Diana A

    2017-08-25

    The processes of thrombosis and coagulation are finely regulated by endogenous fibrinolysis maintaining healthy equilibrium. When the balance is altered in favour of platelet activation and/or coagulation, or if endogenous fibrinolysis becomes less efficient, pathological thrombosis can occur. Arterial thrombosis remains a major cause of morbidity and mortality in the world despite advances in medical therapies. The role endogenous fibrinolysis in the pathogenesis of arterial thrombosis has gained increasing attention in recent years as it presents novel ways to prevent and treat existing diseases. In this review article, we discuss the role of endogenous fibrinolysis in platelet thrombus formation, methods of measurement of fibrinolytic activity, its role in predicting cardiovascular diseases and clinical outcomes and future directions.

  1. Spatial orienting around the fovea: exogenous and endogenous cueing effects.

    Science.gov (United States)

    Yang, Taoxi; Zhang, Jiyuan; Bao, Yan

    2015-09-01

    The effect of covert attention in perifoveal and peripheral locations has been studied extensively. However, it is less clear whether attention operates similarly in the foveal area itself. The present study aims to investigate whether the attentional orienting elicited by an exogenous or endogenous cue can operate within the foveal area and whether attentional orienting operates similarly between foveal and perifoveal regions. By manipulating exogenous orienting in Experiment 1 and endogenous orienting in Experiment 2, we observed both forms of cueing in the foveal area. Specifically, we observed a larger exogenous cue-induced inhibitory effect (i.e., inhibition of return effect) and a similar endogenous cue-elicited facilitatory effect for the perifoveal relative to the foveal targets. We conclude that exogenous and endogenous orienting subject to two independent attentional systems with distinct modulation patterns in the foveal area.

  2. 2.5D Representations Combining in vivo 3D MRI and ex vivo 2D MSI Approaches to Study the Lipid Distribution in the Whole Sheep Brain

    OpenAIRE

    Labas , Valérie; Teixeira-Gomes , Ana Paula; Andersson , Frédéric; Ménigot , Sébastien; Batailler , Martine; Adriaensen , Hans; Migaud , Martine; Chaillou , Elodie

    2015-01-01

    National audience; Mass Spectrometry Imaging (MSI) provides easily high spatially resolved masses allowing characterization of endogenous lipids. These latter constitute about 70% of the composition of the white matter of the brain which can be implicated in developmental and/or cognitive troubles. In order to examine the molecular distribution of lipids in whole sheep brain, and especially in white/grey matter, we combined in vivo and ex vivo images, obtained in the same animals, using Magne...

  3. Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid Mediators of Inflammation to Ameliorate the Deleterious Effects of Blast Overpressure on Eye and Brain Visual Processing Centers in Rats

    Science.gov (United States)

    2014-10-01

    acid ( DHA ; 22:6ω-3) Eicosapentaenoic acid (EPA; 20:5ω-3) Lipoxin A4 Resolvin E1 Protectin DX Resolvin D1 LOX LOX LOX Structures and Endogenous Source...1 AD_________________ Award Number: W81XWH-12-2-0082 TITLE: Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid...Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid Mediators 5a. CONTRACT NUMBER of Inflammation to Ameliorate the Deleterious Effects of

  4. Lipids and membrane lateral organization

    Directory of Open Access Journals (Sweden)

    Sandro eSonnino

    2010-11-01

    Full Text Available Shortly after the elucidation of the very basic structure and properties of cellular membranes, it became evident that cellular membranes are highly organized structures with multiple and multi-dimensional levels of order. Very early observations suggested that the lipid components of biological membranes might be active players in the creations of these levels of order. In the late 80’s, several different and diverse experimental pieces of evidence coalesced together giving rise to the lipid raft hypothesis. Lipid rafts became enormously (and, in the opinion of these authors, sometimes acritically popular, surprisingly not just within the lipidologist community (who is supposed to be naturally sensitive to the fascination of lipid rafts. Today, a PubMed search using the key word lipid rafts returned a list of 3767 papers, including 690 reviews (as a term of comparison, searching over the same time span for a very hot lipid-related key word, ceramide returned 6187 hits with 799 reviews, and a tremendous number of different cellular functions have been described as lipid raft-dependent. However, a clear consensus definition of lipid raft has been proposed only in recent times, and the basic properties, the ruling forces, and even the existence of lipid rafts in living cells have been recently matter of intense debate. The scenario that is gradually emerging from the controversies elicited by the lipid raft hypothesis emphasize multiple roles for membrane lipids in determining membrane order, that encompasses their tendency to phase separation but are clearly not limited to this. In this review, we would like to re-focus the attention of the readers on the importance of lipids in organizing the fine structure of cellular membranes.

  5. Stochastic Stability of Endogenous Growth: Theory and Applications

    OpenAIRE

    Boucekkine, Raouf; Pintus, Patrick; Zou, Benteng

    2015-01-01

    We examine the issue of stability of stochastic endogenous growth. First, stochastic stability concepts are introduced and applied to stochastic linear homogenous differen- tial equations to which several stochastic endogenous growth models reduce. Second, we apply the mathematical theory to two models, starting with the stochastic AK model. It’s shown that in this case exponential balanced paths, which characterize optimal trajectories in the absence of uncertainty, are not robust to uncerta...

  6. A generalized endogenous grid method for discrete-continuous choice

    OpenAIRE

    John Rust; Bertel Schjerning; Fedor Iskhakov

    2012-01-01

    This paper extends Carroll's endogenous grid method (2006 "The method of endogenous gridpoints for solving dynamic stochastic optimization problems", Economic Letters) for models with sequential discrete and continuous choice. Unlike existing generalizations, we propose solution algorithm that inherits both advantages of the original method, namely it avoids all root finding operations, and also efficiently deals with restrictions on the continuous decision variable. To further speed up the s...

  7. A Reformulation of Normative Economics for Models with Endogenous Preferences

    OpenAIRE

    Vipul Bhatt; Masao Ogaki; Yuichi Yaguchi

    2014-01-01

    This paper proposes a framework to balance considerations of welfarism and virtue ethics in the normative analysis of economic models with endogenous preferences. We introduce the moral evaluation function (MEF), which ranks alternatives based purely on virtue ethics, and define the social objective function (SOF), which combines the Social Welfare Function (SWF) and the MEF. In a model of intergenerational altruism with endogenous time preference, using numerical simulations we show that max...

  8. A Reformulation of Normative Economics for Models with Endogenous

    OpenAIRE

    Bhatt, Vipul; Ogaki, Masao; Yaguchi, Yuichi

    2015-01-01

    This paper proposes a framework to balance considerations of welfarism and virtue ethics in the normative analysis of economic models with endogenous preferences. We introduce the moral evaluation function (MEF), which ranks alternatives based purely on virtue ethics, and define the social objective function (SOF), which combines the Social Welfare Function (SWF) and the MEF. In a model of intergenerational altruism with endogenous time preference, using numerical simulations we show that max...

  9. Invasive fungal infections in endogenous Cushing’s syndrome

    Directory of Open Access Journals (Sweden)

    Rafael Selbach Scheffel

    2010-06-01

    Full Text Available Cushing’s syndrome is a condition characterized by elevated cortisol levels that can result from either augmented endogenous production or exogenous administration of corticosteroids. The predisposition to fungal infections among patients with hypercortisolemia has been noted since Cushing’s original description of the disease. We describe here a patient with endo-genous Cushing’s syndrome secondary to an adrenocortical carcinoma, who developed concomitant disseminated cryptococcosis and candidiasis in the course of his disease.

  10. Glacial cycles:exogenous orbital changes vs. endogenous climate dynamics

    OpenAIRE

    Kaufmann, R. K.; Juselius, Katarina

    2010-01-01

    We use a statistical model, the cointegrated vector autoregressive model, to assess the degree to which variations in Earth's orbit and endogenous climate dynamics can be used to simulate glacial cycles during the late Quaternary (390 kyr-present). To do so, we estimate models of varying complexity and compare the accuracy of their in-sample simulations. Results indicate that strong statistical associations between endogenous climate variables are not enough for statistical models to reproduc...

  11. Gut Microbial Glycerol Metabolism as an Endogenous Acrolein Source

    OpenAIRE

    Zhang, Jianbo; Sturla, Shana; Lacroix, Christophe; Schwab, Clarissa

    2018-01-01

    ABSTRACT Acrolein is a highly reactive electrophile causing toxic effects, such as DNA and protein adduction, oxidative stress, endoplasmic reticulum stress, immune dysfunction, and membrane damage. This Opinion/Hypothesis provides an overview of endogenous and exogenous acrolein sources, acrolein’s mode of action, and its metabolic fate. Recent reports underpin the finding that gut microbial glycerol metabolism leading to the formation of reuterin is an additional source of endogenous acrole...

  12. A General Outlook to the Endogenous Money Theory

    OpenAIRE

    ÖZGÜR, Gökçer

    2008-01-01

    The purpose of this study is to shed light on theorigins of the endogenous money theory and analyze the currentdebates on this topic. Endogenous money approach depends on a fundamental postulate: As banks meet the credit needs ofnon-financial businesses, new deposits emerge in the banking sector. Similarly,as the necessary reserves found for these new deposits the broad money expandsas well. Even though the central bank can intervene into this process it cannotfully control it. There...

  13. THE ROLE OF ENTEROSORBENTS IN TREATMENT OF ENDOGENOUS INTOXICATION SYNDROME

    OpenAIRE

    N. I. Ursova

    2012-01-01

    Usage of enterosorbents in treatment of almost all types of acute and chronic disorders accompanied with endogenous intoxication syndrome takes on special significance. The critical point of endogenous intoxication pathogenesis is dysfunction of microbiocenosis and intestinal barrier. The necessity of enterosorbents usage is very high due to their efficacy, safety and wide availability. Smectite dioctaedric (diosmectite), which has been successfully used in clinical practice for a long period...

  14. EXOGENOUS OR ENDOGENOUS MONEY SUPPLY: EVIDENCE FROM AUSTRALIA

    OpenAIRE

    ZATUL E. BADARUDIN; AHMED M. KHALID; MOHAMED ARIFF

    2012-01-01

    This paper investigates the nature of money supply in Australia over two separate monetary policy regimes: monetary and inflation targeting. The post-Keynesian theory on endogenous money was tested with the aim of investigating whether endogenous money supply, if it did exist, followed the accomodationist, structuralist or liquidity preference viewpoints. Data used are quarterly series from 1977 to 2007 and we used vector error-correction model for long-run and short-run causality tests. We f...

  15. Expression of HIV-1 Vpu leads to loss of the viral restriction factor CD317/Tetherin from lipid rafts and its enhanced lysosomal degradation.

    Directory of Open Access Journals (Sweden)

    Ruth Rollason

    Full Text Available CD317/tetherin (aka BST2 or HM1.24 antigen is an interferon inducible membrane protein present in regions of the lipid bilayer enriched in sphingolipids and cholesterol (often termed lipid rafts. It has been implicated in an eclectic mix of cellular processes including, most notably, the retention of fully formed viral particles at the surface of cells infected with HIV and other enveloped viruses. Expression of the HIV viral accessory protein Vpu has been shown to lead to intracellular sequestration and degradation of tetherin, thereby counteracting the inhibition of viral release. There is evidence that tetherin interacts directly with Vpu, but it remains unclear where in the cell this interaction occurs or if Vpu expression affects the lipid raft localisation of tetherin. We have addressed these points using biochemical and cell imaging approaches focused on endogenous rather than ectopically over-expressed tetherin. We find i no evidence for an interaction between Vpu and endogenous tetherin at the cell surface, ii the vast majority of endogenous tetherin that is at the cell surface in control cells is in lipid rafts, iii internalised tetherin is present in non-raft fractions, iv expression of Vpu in cells expressing endogenous tetherin leads to the loss of tetherin from lipid rafts, v internalised tetherin enters early endosomes, and late endosomes, in both control cells and cells expressing Vpu, but the proportion of tetherin molecules destined for degradation rather than recycling is increased in cells expressing Vpu vi lysosomes are the primary site for degradation of endogenous tetherin in cells expressing Vpu. Our studies underlie the importance of studying endogenous tetherin and let us propose a model in which Vpu intercepts newly internalised tetherin and diverts it for lysosomal destruction rather than recycling to the cell surface.

  16. Lipid Peroxidation: Pathophysiology and Pharmacological Implications in the Eye

    Directory of Open Access Journals (Sweden)

    Ya Fatou eNjie-Mbye

    2013-12-01

    Full Text Available Oxygen-derived free radicals such as hydroxyl and hydroperoxyl species have been shown to oxidize phospholipids and other membrane lipid components leading to lipid peroxidation. In the eye, lipid peroxidation has been reported to play an important role in degenerative ocular diseases (age-related macular degeneration, cataract, glaucoma, diabetic retinopathy. Indeed, ocular tissues are prone to damage from reactive oxygen species due to stress from constant exposure of the eye to sunlight, atmospheric oxygen and environmental chemicals. Furthermore, free radical catalyzed peroxidation of long chain polyunsaturated acids (LCPUFAs such as arachidonic acid and docosahexaenoic acid leads to generation of LCPUFA metabolites including isoprostanes and neuroprostanes that may further exert pharmacological/toxicological actions in ocular tissues. Evidence from literature supports the presence of endogenous defense mechanisms against reactive oxygen species in the eye, thereby presenting new avenues for the prevention and treatment of ocular degeneration. Hydrogen peroxide (H2O2 and synthetic peroxides can exert pharmacological and toxicological effects on tissues of the anterior uvea of several mammalian species. There is evidence suggesting that the retina, especially retinal ganglion cells can exhibit unique characteristics of antioxidant defense mechanisms. In the posterior segment of the eye, H2O2 and synthetic peroxides produce an inhibitory action on glutamate release (using [3H]-D-aspartate as a marker, in vitro and on the endogenous glutamate and glycine concentrations in vivo. In addition to peroxides, isoprostanes can elicit both excitatory and inhibitory effects on norepinephrine (NE release from sympathetic nerves in isolated mammalian iris ciliary bodies. Whereas isoprostanes attenuate dopamine release from mammalian neural retina, in vitro, these novel arachidonic acid metabolites exhibit a biphasic regulatory effect on glutamate release

  17. Lipid markers of diet history and their retention during experimental starvation in the Bering Sea euphausiid Thysanoessa raschii

    Science.gov (United States)

    Pleuthner, Rachel L.; Shaw, C. Tracy; Schatz, Megan J.; Lessard, Evelyn J.; Harvey, H. Rodger

    2016-12-01

    Two extended pulsed feeding experiments, following the spring bloom period, investigated lipid retention in the prominent Bering Sea euphausiid (krill) Thysanoessa raschii. These experiments occurred during late spring and early summer of 2010. Concurrent taxonomic analysis of the natural algal community allowed prey type to be linked to lipid composition of the natural communities. In late spring, experimental periods of feeding followed by starvation showed an overall decrease in total lipid for T. raschii. In early summer, no consistent trend was observed for total lipid with the visible presence of storage lipid in some animals. Polar lipids, as phospholipids, were the dominant krill lipid class in both experiments constituting ≥88% of total lipid, and triacylglycerols reached a maximum of 5% of total lipid. The sterols cholesterol and brassicasterol+desmosterol comprised 98-99% of total sterol abundances in T. raschii throughout both experiments, even after feeding periods when alternative sterols (i.e. the algal sterol 24-methylenecholesterol) accounted for up to 39% of sterols in potential food particles. Cholesterol abundance and concentration increased during both incubations, likely due to the metabolism of dietary sterols. Major fatty acids observed in krill included C14:0n, C16:0n, C16:1(n-7), C18:1(n-7), C18:1(n-9), C20:5(n-3), and C22:6(n-3) with the diatom-attributed C16:1(n-7) decreasing in abundance and concentration during starvation. Low concentrations of the dinoflagellate-derived sterol and a novel C28:8 PUFA, typically found in dinoflagellates and prymnesiophytes, indicated predation on protozooplankton in early summer when diatom abundances were low. The stability of lipid distributions over periods of starvation and intermittent feeding suggest that fatty acid and sterol biomarkers present in this polar euphausiid principally reflect long-term diet history rather than short-term feeding episodes.

  18. Therapeutic targeting strategies using endogenous cells and proteins.

    Science.gov (United States)

    Parayath, Neha N; Amiji, Mansoor M

    2017-07-28

    Targeted drug delivery has become extremely important in enhancing efficacy and reducing the toxicity of therapeutics in the treatment of various disease conditions. Current approaches include passive targeting, which relies on naturally occurring differences between healthy and diseased tissues, and active targeting, which utilizes various ligands that can recognize targets expressed preferentially at the diseased site. Clinical translation of these mechanisms faces many challenges including the immunogenic and toxic effects of these non-natural systems. Thus, use of endogenous targeting systems is increasingly gaining momentum. This review is focused on strategies for employing endogenous moieties, which could serve as safe and efficient carriers for targeted drug delivery. The first part of the review involves cells and cellular components as endogenous carriers for therapeutics in multiple disease states, while the second part discusses the use of endogenous plasma components as endogenous carriers. Further understanding of the biological tropism with cells and proteins and the newer generation of delivery strategies that exploits these endogenous approaches promises to provide better solutions for site-specific delivery and could further facilitate clinical translations. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. In situ tissue regeneration: chemoattractants for endogenous stem cell recruitment.

    Science.gov (United States)

    Vanden Berg-Foels, Wendy S

    2014-02-01

    Tissue engineering uses cells, signaling molecules, and/or biomaterials to regenerate injured or diseased tissues. Ex vivo expanded mesenchymal stem cells (MSC) have long been a cornerstone of regeneration therapies; however, drawbacks that include altered signaling responses and reduced homing capacity have prompted investigation of regeneration based on endogenous MSC recruitment. Recent successful proof-of-concept studies have further motivated endogenous MSC recruitment-based approaches. Stem cell migration is required for morphogenesis and organogenesis during development and for tissue maintenance and injury repair in adults. A biomimetic approach to in situ tissue regeneration by endogenous MSC requires the orchestration of three main stages: MSC recruitment, MSC differentiation, and neotissue maturation. The first stage must result in recruitment of a sufficient number of MSC, capable of effecting regeneration, to the injured or diseased tissue. One of the challenges for engineering endogenous MSC recruitment is the selection of effective chemoattractant(s). The objective of this review is to synthesize and evaluate evidence of recruitment efficacy by reported chemoattractants, including growth factors, chemokines, and other more recently appreciated MSC chemoattractants. The influence of MSC tissue sources, cell culture methods, and the in vitro and in vivo environments is discussed. This growing body of knowledge will serve as a basis for the rational design of regenerative therapies based on endogenous MSC recruitment. Successful endogenous MSC recruitment is the first step of successful tissue regeneration.

  20. P-wave dispersion in endogenous and exogenous subclinical hyperthyroidism.

    Science.gov (United States)

    Gen, R; Akbay, E; Camsari, A; Ozcan, T

    2010-02-01

    The aim of this study was to measure maximum P wave duration (Pmax) and P wave dispersion (PWD), which can be indicators for the risk of paroxysmal atrial fibrillation when increased, and to reveal their relationship with thyroid hormone levels in patients with endogenous and exogenous subclinical hyperthyroidism. Seventy-one patients with sublinical thyrotoxicosis (34 endogenous, 37 exogenous) and 69 healthy individuals were enrolled in the study. Pmax and minimum P wave duration (Pmin) on electrocardiogram recordings were measured and PWD was calculated as Pmax-Pmin. Pmax (pendogenous subclinical hyperthyroidism compared with the control group. Pmax (pexogenous subclinical thyrotoxicosis compared with the control group. Pmax (p=0.710) and PWD (p=0.127) were not significantly different in patients with endogenous subclinical hyperthyroidism compared with exogenous subclinical hyperthyroid patients. Pmax and PWD negatively associated with TSH in endogenous and exogenous subclinical hyperthyroidism. In the present study, we observed that Pmax and PWD were longer in patients with endogenous and exogenous subclinical hyperthyroidism. Lack of a difference in Pmax and PWD between patients with endogenous and exogenous subclinical hyperthyroidism seems to support the idea that hormone levels rather than the etiology of thyrotoxicosis affect the heart.

  1. Exogenous and endogenous spatial attention effects on visuospatial working memory.

    Science.gov (United States)

    Botta, Fabiano; Santangelo, Valerio; Raffone, Antonino; Lupiáñez, Juan; Belardinelli, Marta Olivetti

    2010-08-01

    In this study, we investigate how exogenous and endogenous orienting of spatial attention affect visuospatial working memory (VSWM). Specifically, we focused on two attentional effects and their consequences on storage in VSWM, when exogenous (Experiment 1) or endogenous (Experiment 2) orienting cues were used. The first effect, known as the meridian effect, is given by a decrement in behavioural performance when spatial cues and targets are presented in locations separated by vertical and/or horizontal meridians. The second effect, known as the distance effect, is given by a decrement in the orienting effects as a function of the spatial distance between cues and targets. Our results revealed a dissociation between exogenous and endogenous orienting mechanisms in terms of both meridian and distance effects. We found that meridian crossing affects performance only when endogenous cues were used. Specifically, VSWM performance with endogenous cueing depended more on the number of meridian crossings than on distance between cue and target. By contrast, a U-shaped distance dependency was observed using exogenous cues. Our findings therefore suggest that exogenous and endogenous orienting mechanisms lead to different forms of attentional bias for storage in VSWM.

  2. Application of Next Generation Sequencing in Mammalian Embryogenomics: Lessons Learned from Endogenous Betaretroviruses of Sheep

    Science.gov (United States)

    Spencer, Thomas E.; Palmarini, Massimo

    2012-01-01

    Endogenous retroviruses (ERVs) are present in the genome of all vertebrates and are remnants of ancient exogenous retroviral infections of the host germline transmitted vertically from generation to generation. The sheep genome contains 27 JSRV-related endogenous betaretroviruses (enJSRVs) related to the pathogenic Jaagsiekte sheep retrovirus (JSRV) that have been integrating in the host genome for the last 5 to 7 million years. The exogenous JSRV is a causative agent of a transmissible lung cancer in sheep, and enJSRVs are able to protect the host against JSRV infection. In sheep, the enJSRVs are most abundantly expressed in the uterine epithelia as well as in the conceptus (embryo and associated extraembryonic membranes) trophectoderm. Sixteen of the 27 enJSRV loci contain an envelope (env) gene with an intact open reading frame, and in utero loss-of-function experiments found the enJSRVs Env to be essential for trophoblast outgrowth and conceptus elongation. Collectively, available evidence supports the ideas that genes captured from ancestral retroviruses were pivotal in the acquisition of new, important functions in mammalian evolution and were positively selected for biological roles in genome plasticity, protection of the host against infection of related pathogenic and exogenous retroviruses, and a convergent physiological role in placental morphogenesis and thus mammalian reproduction. The discovery of ERVs in mammals was initially based on molecular cloning discovery techniques and will be boosted forward by next generation sequencing technologies and in silico discovery techniques. PMID:22951118

  3. A Conserved Circular Network of Coregulated Lipids Modulates Innate Immune Responses.

    Science.gov (United States)

    Köberlin, Marielle S; Snijder, Berend; Heinz, Leonhard X; Baumann, Christoph L; Fauster, Astrid; Vladimer, Gregory I; Gavin, Anne-Claude; Superti-Furga, Giulio

    2015-07-02

    Lipid composition affects the biophysical properties of membranes that provide a platform for receptor-mediated cellular signaling. To study the regulatory role of membrane lipid composition, we combined genetic perturbations of sphingolipid metabolism with the quantification of diverse steps in Toll-like receptor (TLR) signaling and mass spectrometry-based lipidomics. Membrane lipid composition was broadly affected by these perturbations, revealing a circular network of coregulated sphingolipids and glycerophospholipids. This evolutionarily conserved network architecture simultaneously reflected membrane lipid metabolism, subcellular localization, and adaptation mechanisms. Integration of the diverse TLR-induced inflammatory phenotypes with changes in lipid abundance assigned distinct functional roles to individual lipid species organized across the network. This functional annotation accurately predicted the inflammatory response of cells derived from patients suffering from lipid storage disorders, based solely on their altered membrane lipid composition. The analytical strategy described here empowers the understanding of higher-level organization of membrane lipid function in diverse biological systems. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Organization of lipids in the tear film: a molecular-level view.

    Directory of Open Access Journals (Sweden)

    Alicja Wizert

    Full Text Available Biophysical properties of the tear film lipid layer are studied at the molecular level employing coarse grain molecular dynamics (MD simulations with a realistic model of the human tear film. In this model, polar lipids are chosen to reflect the current knowledge on the lipidome of the tear film whereas typical Meibomian-origin lipids are included in the thick non-polar lipids subphase. Simulation conditions mimic those experienced by the real human tear film during blinks. Namely, thermodynamic equilibrium simulations at different lateral compressions are performed to model varying surface pressure, and the dynamics of the system during a blink is studied by non-equilibrium MD simulations. Polar lipids separate their non-polar counterparts from water by forming a monomolecular layer whereas the non-polar molecules establish a thick outermost lipid layer. Under lateral compression, the polar layer undulates and a sorting of polar lipids occurs. Moreover, formation of three-dimensional aggregates of polar lipids in both non-polar and water subphases is observed. We suggest that these three-dimensional structures are abundant under dynamic conditions caused by the action of eye lids and that they act as reservoirs of polar lipids, thus increasing stability of the tear film.

  5. Effects of hormones on lipids and lipoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, R.M.

    1991-12-01

    Levels of plasma lipids and lipoproteins are strong predictors for the development of atherosclerotic cardiovascular disease in postmenopausal women. In women, as in men, numerous factors contribute to variations in plasma lipoproteins that may affect cardiovascular disease risk. These include age, dietary components, adiposity, genetic traits, and hormonal changes. Each of these factors may operate to varying degrees in determining changes in plasma lipoprotein profiles accompanying menopause- Cross-sectional and longitudinal studies have suggested increases in levels of cholesterol, low density lipoproteins (LDL) and triglyceride-rich lipoproteins associated with menopause. High density lipoproteins (HDL), which are higher in women than men and are thought to contribute to relative protection of premenopausal women from cardiovascular disease, remain relatively constant in the years following menopause, although small, and perhaps transient reductions in the HDL{sub 2} subfraction have been reported in relation to reduced estradiol level following menopause. Despite these associations, it has been difficult to determine the role of endogenous hormones in influencing the plasma lipoproteins of postmenopausal women. In principle, the effects of hormone replacement should act to reverse any alterations in lipoprotein metabolism that are due to postmenopausal hormone changes. While there may be beneficial effects on lipoproteins, hormone treatment does not restore a premenopausal lipoprotein profile. Furthermore, it is not dear to what extent exogenous hormone-induced lipoprotein changes contribute to the reduced incidence of cardiovascular disease with hormone replacement therapy.

  6. Unraveling lipid metabolism in lipid-dependent pathogenic Malassezia yeasts

    NARCIS (Netherlands)

    Celis Ramirez, A.M.

    2017-01-01

    Malassezia yeasts are lipid-dependent fungal species that are common members of the human and animal skin microbiota. The lipid-dependency is a crucial trait in the adaptation process to grow on the skin but also plays a role in their pathogenic life style. Malassezia species can cause several skin

  7. Update of the LIPID MAPS comprehensive classification system for lipids

    NARCIS (Netherlands)

    Fahy, E.; Subramaniam, S.; Murphy, R.C.; Nishijima, M.; Raetz, C.R.H.; Shimizu, T.; Spener, F.; van Meer, G.|info:eu-repo/dai/nl/068570368; Wakelam, M.J.O.; Dennis, E.A.

    2009-01-01

    In 2005, the International Lipid Classification and Nomenclature Committee under the sponsorship of the LIPID MAPS Consortium developed and established a “Comprehensive Classification System for Lipids” based on well-defined chemical and biochemical principles and using an ontology that is

  8. Abundance Tomography of Type Ia Supernovae

    International Nuclear Information System (INIS)

    Stehle, M.; Mazzali, P.A.; Hillebrandt, W.

    2005-01-01

    An analysis of early time spectra of Type Ia Supernovae is presented. A new method to derive a detailed abundance distribution of the SN ejecta through comparison with synthetic spectra, called 'Abundance Tomography' is introduced and applied to the normal SN Ia 2002bo. Conclusions regarding the explosion mechanism are drawn

  9. Diversity, composition and abundance of macroinvertebrates ...

    African Journals Online (AJOL)

    user

    these genera were found at all sampling stations as shown in Table 2. Out of the orders sampled, Hemiptera, Pulmonata and. Coleoptera had the highest number of genera with 5, 4 and 4, respectively. In terms of relative abundance, dipterans and Pulmonata were the most abundant while. Hydracarina (water mites) were ...

  10. Resource Abundance and Resource Dependence in China

    NARCIS (Netherlands)

    Ji, K.; Magnus, J.R.; Wang, W.

    2010-01-01

    This paper reconsiders the ‘curse of resources’ hypothesis for the case of China, and distinguishes between resource abundance, resource rents, and resource dependence. Resource abundance and resource rents are shown to be approximately equivalent, and their association with resource dependence

  11. Determinants of distribution, abundance and reproductive success ...

    African Journals Online (AJOL)

    ... while local vegetation structure determines the abundance of locally established populations. The abundance of trees affects nest site availability and breeding success, based on observations at two oases. Blackbird nests were usually situated on pomegranate trees and olive trees. The Common Blackbird is a successful ...

  12. Diversity and abundance of ammonia-oxidizing

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; van Bleijswijk, J.D.L.; Witte, H.; van Duyl, F.C.

    2013-01-01

    We analysed the diversity and abundance of ammonia-oxidizing Archaea (AOA) and Bacteria (AOB) in the shallow warm-water sponge Halisarca caerulea and the deep cold-water sponges Higginsia thielei and Nodastrella nodastrella. The abundance of AOA and AOB was analysed using catalyzed reporter

  13. Cell-based lipid flippase assay employing fluorescent lipid derivatives

    DEFF Research Database (Denmark)

    Jensen, Maria Stumph; Costa, Sara; Günther-Pomorski, Thomas

    2016-01-01

    P-type ATPases in the P4 subfamily (P4-ATPases) are transmembrane proteins unique for eukaryotes that act as lipid flippases, i.e., to translocate phospholipids from the exofacial to the cytofacial monolayer of cellular membranes. While initially characterized as aminophospholipid translocases, s...... flippase activities in the plasma membrane of cells, using yeast as an example.......P-type ATPases in the P4 subfamily (P4-ATPases) are transmembrane proteins unique for eukaryotes that act as lipid flippases, i.e., to translocate phospholipids from the exofacial to the cytofacial monolayer of cellular membranes. While initially characterized as aminophospholipid translocases......, studies of individual P4-ATPase family members from fungi, plants, and animals show that P4-ATPases differ in their substrate specificities and mediate transport of a broader range of lipid substrates. Here, we describe an assay based on fluorescent lipid derivatives to monitor and characterize lipid...

  14. Stellar pulsation and the abundance of helium

    International Nuclear Information System (INIS)

    Schmidt, E.G.

    1978-01-01

    It has been suggested that the appearance of nonvariable stars within the Cepheid strip could be explained by a range in the helium abundance of Population I stars. In order to study this possibility, spectra were obtained of the main-sequence B stars in the galactic cluster NGC 129, which contains a nonvariable Cepheid-strip star, and M25, which contains a relatively hot Cepheid. Unfortunately, several of the stars in these clusters turn out to be helium-weak stars. In NGC 129 two stars which appear normal give a normal abundance, while in M25 all of the observed stars have abnormally low abundances. The significance of the low abundance in M25 is not clear. The abundance in NGC 129 is not low enough to support the above suggestion. 4 figures, 2 tables

  15. Solid lipid nanoparticles for parenteral drug delivery

    NARCIS (Netherlands)

    Wissing, S.A.; Kayser, Oliver; Muller, R.H.

    2004-01-01

    This review describes the use of nanoparticles based on solid lipids for the parenteral application of drugs. Firstly, different types of nanoparticles based on solid lipids such as "solid lipid nanoparticles" (SLN), "nanostructured lipid carriers" (NLC) and "lipid drug conjugate" (LDC)

  16. Analysis of lipid profile in lipid storage myopathy.

    Science.gov (United States)

    Aguennouz, M'hammed; Beccaria, Marco; Purcaro, Giorgia; Oteri, Marianna; Micalizzi, Giuseppe; Musumesci, Olimpia; Ciranni, Annmaria; Di Giorgio, Rosa Maria; Toscano, Antonio; Dugo, Paola; Mondello, Luigi

    2016-09-01

    Lipid dysmetabolism disease is a condition in which lipids are stored abnormally in organs and tissues throughout the body, causing muscle weakness (myopathy). Usually, the diagnosis of this disease and its characterization goes through dosage of Acyl CoA in plasma accompanied with evidence of droplets of intra-fibrils lipids in the patient muscle biopsy. However, to understand the pathophysiological mechanisms of lipid storage diseases, it is useful to identify the nature of lipids deposited in muscle fiber. In this work fatty acids and triglycerides profile of lipid accumulated in the muscle of people suffering from myopathies syndromes was characterized. In particular, the analyses were carried out on the muscle biopsy of people afflicted by lipid storage myopathy, such as multiple acyl-coenzyme A dehydrogenase deficiency, and neutral lipid storage disease with myopathy, and by the intramitochondrial lipid storage dysfunctions, such as deficiencies of carnitine palmitoyltransferase II enzyme. A single step extraction and derivatization procedure was applied to analyze fatty acids from muscle tissues by gas chromatography with a flame ionization detector and with an electronic impact mass spectrometer. Triglycerides, extracted by using n-hexane, were analyzed by high performance liquid chromatography coupled to mass spectrometer equipped with an atmospheric pressure chemical ionization interface. The most representative fatty acids in all samples were: C16:0 in the 13-24% range, C18:1n9 in the 20-52% range, and C18:2n6 in the 10-25% range. These fatty acids were part of the most representative triglycerides in all samples. The data obtained was statistically elaborated performing a principal component analysis. A satisfactory discrimination was obtained among the different diseases. Using component 1 vs component 3 a 43.3% of total variance was explained. Such results suggest the important role that lipid profile characterization can have in supporting a correct

  17. Influence of Coronal Abundance Variations

    Science.gov (United States)

    Scargle, Jeffrey D. (Technical Monitor); Kashyap, Vinay

    2005-01-01

    The PI of this project was Jeff Scargle of NASA/Ames. Co-I's were Alma Connors of Eureka Scientific/Wellesley, and myself. Part of the work was subcontracted to Eureka Scientific via SAO, with Vinay Kashyap as PI. This project was originally assigned grant number NCC2-1206, and was later changed to NCC2-1350 for administrative reasons. The goal of the project was to obtain, derive, and develop statistical and data analysis tools that would be of use in the analyses of high-resolution, high-sensitivity data that are becoming available with new instruments. This is envisioned as a cross-disciplinary effort with a number of "collaborators" including some at SA0 (Aneta Siemiginowska, Peter Freeman) and at the Harvard Statistics department (David van Dyk, Rostislav Protassov, Xiao-li Meng, Epaminondas Sourlas, et al). We have developed a new tool to reliably measure the metallicities of thermal plasma. It is unfeasible to obtain high-resolution grating spectra for most stars, and one must make the best possible determination based on lower-resolution, CCD-type spectra. It has been noticed that most analyses of such spectra have resulted in measured metallicities that were significantly lower than when compared with analyses of high- resolution grating data where available (see, e.g., Brickhouse et al., 2000, ApJ 530,387). Such results have led to the proposal of the existence of so-called Metal Abundance Deficient, or "MAD" stars (e.g., Drake, J.J., 1996, Cool Stars 9, ASP Conf.Ser. 109, 203). We however find that much of these analyses may be systematically underestimating the metallicities, and using a newly developed method to correctly treat the low-counts regime at the high-energy tail of the stellar spectra (van Dyk et al. 2001, ApJ 548,224), have found that the metallicities of these stars are generally comparable to their photospheric values. The results were reported at the AAS (Sourlas, Yu, van Dyk, Kashyap, and Drake, 2000, BAAS 196, v32, #54.02), and at the

  18. Unraveling the Complex Relationship Triad between Lipids, Obesity, and Inflammation

    Directory of Open Access Journals (Sweden)

    Shahida A. Khan

    2014-01-01

    Full Text Available Obesity today stands at the intersection between inflammation and metabolic disorders causing an aberration of immune activity, and resulting in increased risk for diabetes, atherosclerosis, fatty liver, and pulmonary inflammation to name a few. Increases in mortality and morbidity in obesity related inflammation have initiated studies to explore different lipid mediated molecular pathways of attempting resolution that uncover newer therapeutic opportunities of anti-inflammatory components. Majorly the thromboxanes, prostaglandins, leukotrienes, lipoxins, and so forth form the group of lipid mediators influencing inflammation. Of special mention are the omega-6 and omega-3 fatty acids that regulate inflammatory mediators of interest in hepatocytes and adipocytes via the cyclooxygenase and lipoxygenase pathways. They also exhibit profound effects on eicosanoid production. The inflammatory cyclooxygenase pathway arising from arachidonic acid is a critical step in the progression of inflammatory responses. New oxygenated products of omega-3 metabolism, namely, resolvins and protectins, behave as endogenous mediators exhibiting powerful anti-inflammatory and immune-regulatory actions via the peroxisome proliferator-activated receptors (PPARs and G protein coupled receptors (GPCRs. In this review we attempt to discuss the complex pathways and links between obesity and inflammation particularly in relation to different lipid mediators.

  19. The Flexibility of Ectopic Lipids

    Directory of Open Access Journals (Sweden)

    Hannah Loher

    2016-09-01

    Full Text Available In addition to the subcutaneous and the visceral fat tissue, lipids can also be stored in non-adipose tissue such as in hepatocytes (intrahepatocellular lipids; IHCL, skeletal (intramyocellular lipids; IMCL or cardiac muscle cells (intracardiomyocellular lipids; ICCL. Ectopic lipids are flexible fuel stores that can be depleted by physical exercise and repleted by diet. They are related to obesity and insulin resistance. Quantification of IMCL was initially performed invasively, using muscle biopsies with biochemical and/or histological analysis. 1H-magnetic resonance spectroscopy (1H-MRS is now a validated method that allows for not only quantifying IMCL non-invasively and repeatedly, but also assessing IHCL and ICCL. This review summarizes the current available knowledge on the flexibility of ectopic lipids. The available evidence suggests a complex interplay between quantitative and qualitative diet, fat availability (fat mass, insulin action, and physical exercise, all important factors that influence the flexibility of ectopic lipids. Furthermore, the time frame of the intervention on these parameters (short-term vs. long-term appears to be critical. Consequently, standardization of physical activity and diet are critical when assessing ectopic lipids in predefined clinical situations.

  20. Neuroimaging of Lipid Storage Disorders

    Science.gov (United States)

    Rieger, Deborah; Auerbach, Sarah; Robinson, Paul; Gropman, Andrea

    2013-01-01

    Lipid storage diseases, also known as the lipidoses, are a group of inherited metabolic disorders in which there is lipid accumulation in various cell types, including the central nervous system, because of the deficiency of a variety of enzymes. Over time, excessive storage can cause permanent cellular and tissue damage. The brain is particularly…

  1. Fasting and nonfasting lipid levels

    DEFF Research Database (Denmark)

    Langsted, Anne; Freiberg, Jacob J; Nordestgaard, Børge G

    2008-01-01

    Lipid profiles are usually measured after fasting. We tested the hypotheses that these levels change only minimally in response to normal food intake and that nonfasting levels predict cardiovascular events.......Lipid profiles are usually measured after fasting. We tested the hypotheses that these levels change only minimally in response to normal food intake and that nonfasting levels predict cardiovascular events....

  2. Lipid and bile acid analysis

    NARCIS (Netherlands)

    Argmann, Carmen A.; Houten, Sander M.; Champy, Marie-France; Auwerx, Johan

    2006-01-01

    Lipids are important body constituents that are vital for cellular, tissue, and whole-body homeostasis. Lipids serve as crucial membrane components, constitute the body's main energy reservoir, and are important signaling molecules. As a consequence of these pleiotropic functions, many common

  3. Endogenous Cortical Oscillations Constrain Neuromodulation by Weak Electric Fields

    Science.gov (United States)

    Schmidt, Stephen L.; Iyengar, Apoorva K.; Foulser, A. Alban; Boyle, Michael R.; Fröhlich, Flavio

    2014-01-01

    Background Transcranial alternating current stimulation (tACS) is a non-invasive brain stimulation modality that may modulate cognition by enhancing endogenous neocortical oscillations with the application of sine-wave electric fields. Yet, the role of endogenous network activity in enabling and shaping the effects of tACS has remained unclear. Objective We combined optogenetic stimulation and multichannel slice electrophysiology to elucidate how the effect of weak sine-wave electric field depends on the ongoing cortical oscillatory activity. We hypothesized that the structure of the response to stimulation depended on matching the stimulation frequency to the endogenous cortical oscillation. Methods We studied the effect of weak sine-wave electric fields on oscillatory activity in mouse neocortical slices. Optogenetic control of the network activity enabled the generation of in vivo like cortical oscillations for studying the temporal relationship between network activity and sine-wave electric field stimulation. Results Weak electric fields enhanced endogenous oscillations but failed to induce a frequency shift of the ongoing oscillation for stimulation frequencies that were not matched to the endogenous oscillation. This constraint on the effect of electric field stimulation imposed by endogenous network dynamics was limited to the case of weak electric fields targeting in vivo-like network dynamics. Together, these results suggest that the key mechanism of tACS may be enhancing but not overriding of intrinsic network dynamics. Conclusion Our results contribute to understanding the inconsistent tACS results from human studies and propose that stimulation precisely adjusted in frequency to the endogenous oscillations is key to rational design of non-invasive brain stimulation paradigms. PMID:25129402

  4. Lysosomal degradation of membrane lipids.

    Science.gov (United States)

    Kolter, Thomas; Sandhoff, Konrad

    2010-05-03

    The constitutive degradation of membrane components takes place in the acidic compartments of a cell, the endosomes and lysosomes. Sites of lipid degradation are intralysosomal membranes that are formed in endosomes, where the lipid composition is adjusted for degradation. Cholesterol is sorted out of the inner membranes, their content in bis(monoacylglycero)phosphate increases, and, most likely, sphingomyelin is degraded to ceramide. Together with endosomal and lysosomal lipid-binding proteins, the Niemann-Pick disease, type C2-protein, the GM2-activator, and the saposins sap-A, -B, -C, and -D, a suitable membrane lipid composition is required for degradation of complex lipids by hydrolytic enzymes. Copyright 2009 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  5. Production of n-alkyl lipids in living plants and implications for the geologic past

    Science.gov (United States)

    Diefendorf, Aaron F.; Freeman, Katherine H.; Wing, Scott L.; Graham, Heather V.

    2011-12-01

    Leaf waxes (i.e., n-alkyl lipids or n-alkanes) are land-plant biomarkers widely used to reconstruct changes in climate and the carbon isotopic composition of the atmosphere. There is little information available, however, on how the production of leaf waxes by different kinds of plants might influence the abundance and isotopic composition of n-alkanes in sedimentary archives. This lack of information increases uncertainty in interpreting n-alkyl lipid abundance and δ 13C signals in ancient settings. We provide here n-alkyl abundance distributions and carbon isotope fractionation data for deciduous and evergreen angiosperm and gymnosperm leaves from 46 tree species, representing 24 families. n-Alkane abundances are significantly higher in angiosperms than gymnosperms; many of the gymnosperm species investigated did not produce any n-alkanes. On average, deciduous angiosperms produce 200 times more n-alkanes than deciduous gymnosperms. Although differences between angiosperms and gymnosperms dominate the variance in n-alkane abundance, leaf life-span is also important, with higher n-alkane abundances in longer-lived leaves. n-Alkanol abundances covary with n-alkanes, but n-alkanoic acids have similar abundances across all plant groups. Isotopic fractionation between leaf tissue and individual alkanes ( ɛlipid) varies by as much as 10‰ among different chain lengths. Overall, ɛlipid values are slightly lower (-4.5‰) for angiosperm than for gymnosperm (-2.5‰) n-alkanes. Angiosperms commonly express slightly higher Δleaf (photosynthetic discrimination) relative to gymnosperms under similar growth conditions. As a result, angiosperm n-alkanes are expected to be generally 3-5‰ more depleted in 13C relative to gymnosperm alkanes for the same locality. Differences in n-alkane production indicate the biomarker record will largely (but not exclusively) reflect angiosperms if both groups were present, and also that evergreen plants will likely be overrepresented

  6. Kinetic modeling of growth and lipid body induction in Chlorella pyrenoidosa under heterotrophic conditions.

    Science.gov (United States)

    Sachdeva, Neha; Kumar, G Dinesh; Gupta, Ravi Prakash; Mathur, Anshu Shankar; Manikandan, B; Basu, Biswajit; Tuli, Deepak Kumar

    2016-10-01

    The aim of the present work was to develop a mathematical model to describe the biomass and (total) lipid productivity of Chlorella pyrenoidosa NCIM 2738 under heterotrophic conditions. Biomass growth rate was predicted by Droop's cell quota model, while changes observed in cell quota (utilization) under carbon excess conditions were used for the modeling and predicting the lipid accumulation rate. The model was simulated under non-limiting (excess) carbon and limiting nitrate concentration and validated with experimental data for the culture grown in batch (flask) mode under different nitrate concentrations. The present model incorporated two modes (growth and stressed) for the prediction of endogenous lipid synthesis/induction and aimed to predict the effect and response of the microalgae under nutrient starvation (stressed) conditions. MATLAB and Genetic Algorithm were employed for the prediction and validation of the model parameters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Interstellar Abundances Toward X Per, Revisited

    Science.gov (United States)

    Valencic, Lynne A.; Smith, Randall K.

    2014-01-01

    The nearby X-ray binary X Per (HD 24534) provides a useful beacon with which to measure elemental abundances in the local ISM. We examine absorption features of 0, Mg, and Si along this line of sight using spectra from the Chandra Observatory's LETG/ ACIS-S and XMM-Newton's RGS instruments. In general, we find that the abundances and their ratios are similar to those of young F and G stars and the most recent solar values. We compare our results with abundances required by dust grain models.

  8. Abundance variations in solar active regions

    Science.gov (United States)

    Strong, K. T.; Lemen, J. R.; Linford, G. A.

    1991-01-01

    The diversity in the published values of coronal abundances is unsettling, especially as the range of results seems to be beyond the quoted uncertainties. Measurements of the relative abundance of iron and neon derived from soft X-ray spectra of active regions are presented. From a data base of over 200 spectra taken by the Solar Maximum Mission Flat Crystal Spectrometer, it is found that the relative abundance can vary by as much as a factor of about 7 and can change on timescales of less than 1 h.

  9. Particulate sulfur-containing lipids: Production and cycling from the epipelagic to the abyssopelagic zone

    Science.gov (United States)

    Gašparović, Blaženka; Penezić, Abra; Frka, Sanja; Kazazić, Saša; Lampitt, Richard S.; Holguin, F. Omar; Sudasinghe, Nilusha; Schaub, Tanner

    2018-04-01

    There are major gaps in our understanding of the distribution and role of lipids in the open ocean especially with regard to sulfur-containing lipids (S-lipids). Here, we employ a powerful analytical approach based on high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to elucidate depth-related S-lipid production and molecular transformations in suspended particulate matter from the Northeast Atlantic Ocean in this depth range. We show that within the open-ocean environment S-lipids contribute up to 4.2% of the particulate organic carbon, and that up to 95% of these compounds have elemental compositions that do not match those found in the Nature Lipidomics Gateway database (termed "novel"). Among the remaining 5% of lipids that match the database, we find that sulphoquinovosyldiacylglycerol (SQDG) are efficiently removed while sinking through the mesopelagic zone. The relative abundance of other assigned lipids (sulphoquinovosylmonoacylglycerol (SQMG), sulfite and sulfate lipids, Vitamin D2 and D3 derivatives, and sphingolipids) did not change substantially with depth. The novel S-lipids, represented by hundreds of distinct elemental compositions (160-300 molecules at any one depth), contribute increasingly to the lipid and particulate organic matter pools with increased depth. Depth-related transformations cause (i) incomplete degradation/transformation of unsaturated S-lipids which leads to the depth-related accumulation of the refractory saturated compounds with reduced molecular weight (average 455 Da) and (ii) formation of highly unsaturated S-lipids (average abyssopelagic molecular double bond equivalents, DBE=7.8) with lower molecular weight (average 567 Da) than surface S-lipids (average 592 Da). A depth-related increase in molecular oxygen content is observed for all novel S-lipids and indicates that oxidation has a significant role in their transformation while (bio)hydrogenation possibly impacts the formation of

  10. Tissue-specific tagging of endogenous loci in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Kate Koles

    2016-01-01

    Full Text Available Fluorescent protein tags have revolutionized cell and developmental biology, and in combination with binary expression systems they enable diverse tissue-specific studies of protein function. However these binary expression systems often do not recapitulate endogenous protein expression levels, localization, binding partners and/or developmental windows of gene expression. To address these limitations, we have developed a method called T-STEP (tissue-specific tagging of endogenous proteins that allows endogenous loci to be tagged in a tissue specific manner. T-STEP uses a combination of efficient CRISPR/Cas9-enhanced gene targeting and tissue-specific recombinase-mediated tag swapping to temporally and spatially label endogenous proteins. We have employed this method to GFP tag OCRL (a phosphoinositide-5-phosphatase in the endocytic pathway and Vps35 (a Parkinson's disease-implicated component of the endosomal retromer complex in diverse Drosophila tissues including neurons, glia, muscles and hemocytes. Selective tagging of endogenous proteins allows, for the first time, cell type-specific live imaging and proteomics in complex tissues.

  11. Endogenous versus Exogenous Growth Factor Regulation of Articular Chondrocytes

    Science.gov (United States)

    Shi, Shuiliang; Chan, Albert G.; Mercer, Scott; Eckert, George J.; Trippel, Stephen B.

    2014-01-01

    Anabolic growth factors that regulate the function of articular chondrocytes are candidates for articular cartilage repair. Such factors may be delivered by pharmacotherapy in the form of exogenous proteins, or by gene therapy as endogenous proteins. It is unknown whether delivery method influences growth factor effectiveness in regulating articular chondrocyte reparative functions. We treated adult bovine articular chondrocytes with exogenous recombinant insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1), or with the genes encoding these growth factors for endogenous production. Treatment effects were measured as change in chondrocyte DNA content, glycosaminoglycan production, and aggrecan gene expression. We found that IGF-I stimulated chondrocyte biosynthesis similarly when delivered by either exogenous or endogenous means. In contrast, exogenous TGF-ß1 stimulated these reparative functions, while endogenous TGF-ß1 had little effect. Endogenous TGF-ß1 became more bioactive following activation of the transgene protein product. These data indicate that effective mechanisms of growth factor delivery for articular cartilage repair may differ for different growth factors. In the case of IGF-I, gene therapy or protein therapy appear to be viable options. In contrast, TGF-ß1 gene therapy may be constrained by a limited ability of chondrocytes to convert latent complexes to an active form. PMID:24105960

  12. Biopsychosocial Factors Associated with Prurigo Nodularis in Endogenous Eczema.

    Science.gov (United States)

    Oh, Choon Chiat; Li, Huihua; Lee, Wellington; Tey, Hong Liang

    2015-01-01

    Prurigo nodularis is a dermatological manifestation secondary to chronic scratching or picking on focal areas of the skin. Its pathogenesis remains poorly understood, and limited data has indicated its association with psychological factors. To determine the biological, psychological and social factors associated with the occurrence of prurigo nodularis in patients with underlying endogenous eczema. A prospective case-control questionnaire -based study on patients with endogenous eczema, with and without prurigo nodules, was performed. The Impact of Skin Disease on Daily Life questionnaire was used to assess dimensions of physical functioning, including extent and severity of skin disease, itch, pain, fatigue and scratching, as well as dimensions of psychological and social functioning, including mood, illness cognition, disease-related impact, stigmatization and social support. Thirty-six cases and 47 controls were recruited. Patients with endogenous eczema and prurigo nodules indicated a higher itch score on the visual analog scale over the previous 4 weeks compared to those without prurigo nodules (p=0.0292). There were no significant differences between the 2 groups in the scores reflecting the other parameters of physical, psychological and social functioning. In patients with endogenous eczema, those with prurigo nodules experience a greater itch intensity compared to those without prurigo nodules. There were no other physical, psychological and social factors that were found to be associated with the occurrence of prurigo nodules in endogenous eczema.

  13. Staphylococcal endogenous endophthalmitis in association with pyogenic vertebral osteomyelitis.

    Science.gov (United States)

    Steeples, L R; Jones, N P

    2016-01-01

    PURPOSE To describe pyogenic vertebral osteomyelitis as a rare infection associated with endogenous endophthalmitis.METHODS A retrospective review of three patients with endogenous endophthalmitis and sepsis due to underlying Staphylococcal vertebral osteomyelitis presenting during a 21-month time period. The ophthalmic and systemic features and management and outcomes are presented.RESULTS One patient developed unilateral endophthalmitis with cervical spine osteomyelitis, Staphylococcus aureus being isolated from blood cultures. The second presented with bilateral endophthalmitis with disseminated Methicillin-resistant S. aureus (MRSA) infection, with thoracic and lumbar discitis and para-spinal abscesses. MRSA was cultured from vitreous, blood, and synovial fluid. Both patients received prolonged courses of intravenous antibiotics. Intravitreal antibiotic therapy was used in the second patient. Excellent visual and systemic outcomes were achieved in both cases with no ocular complications. The third patient developed lumbar osteomyelitis following spinal surgery and presented with disseminated S. aureus sepsis including unilateral endogenous endophthalmitis. Despite systemic antibiotics and intensive care the patient died.CONCLUSIONS Endogenous endophthalmitis should be suspected in septic patients developing eye symptoms. Endogenous endophthalmitis with staphylococcal bone infection is a rare but serious condition. Osteomyelitis should be considered as an infective source in any such patient reporting bone pain or reduced spinal mobility. Prompt investigation and treatment can achieve favourable visual and systemic outcomes.

  14. Endogenous Cartilage Repair by Recruitment of Stem Cells.

    Science.gov (United States)

    Im, Gun-Il

    2016-04-01

    Articular cartilage has a very limited capacity for repair after injury. The adult body has a pool of stem cells that are mobilized during injury or disease. These cells exist inside niches in bone marrow, muscle, adipose tissue, synovium, and other connective tissues. A method that mobilizes this endogenous pool of stem cells will provide a less costly and less invasive alternative if these cells successfully regenerate defective cartilage. Traditional microfracture procedures employ the concept of bone marrow stimulation to regenerate cartilage. However, the regenerated tissue usually is fibrous cartilage, which has very poor mechanical properties compared to those of normal hyaline cartilage. A method that directs the migration of a large number of autologous mesenchymal stem cells toward injury sites, retains these cells around the defects, and induces chondrogenic differentiation that would enhance success of endogenous cartilage repair. This review briefly summarizes chemokines and growth factors that induce recruitment, proliferation, and differentiation of endogenous progenitor cells, endogenous cell sources for regenerating cartilage, scaffolds for delivery of bioactive factors, and bioadhesive materials that are necessary to bring about endogenous cartilage repair.

  15. Endogenous versus exogenous growth factor regulation of articular chondrocytes.

    Science.gov (United States)

    Shi, Shuiliang; Chan, Albert G; Mercer, Scott; Eckert, George J; Trippel, Stephen B

    2014-01-01

    Anabolic growth factors that regulate the function of articular chondrocytes are candidates for articular cartilage repair. Such factors may be delivered by pharmacotherapy in the form of exogenous proteins, or by gene therapy as endogenous proteins. It is unknown whether delivery method influences growth factor effectiveness in regulating articular chondrocyte reparative functions. We treated adult bovine articular chondrocytes with exogenous recombinant insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1), or with the genes encoding these growth factors for endogenous production. Treatment effects were measured as change in chondrocyte DNA content, glycosaminoglycan production, and aggrecan gene expression. We found that IGF-I stimulated chondrocyte biosynthesis similarly when delivered by either exogenous or endogenous means. In contrast, exogenous TGF-β1 stimulated these reparative functions, while endogenous TGF-β1 had little effect. Endogenous TGF-β1 became more bioactive following activation of the transgene protein product. These data indicate that effective mechanisms of growth factor delivery for articular cartilage repair may differ for different growth factors. In the case of IGF-I, gene therapy or protein therapy appear to be viable options. In contrast, TGF-β1 gene therapy may be constrained by a limited ability of chondrocytes to convert latent complexes to an active form. Published 2013 by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. This article is a U.S. Government work and is in the public domain in the USA.

  16. Innate heart regeneration: endogenous cellular sources and exogenous therapeutic amplification.

    Science.gov (United States)

    Malliaras, Konstantinos; Vakrou, Styliani; Kapelios, Chris J; Nanas, John N

    2016-11-01

    The -once viewed as heretical- concept of the adult mammalian heart as a dynamic organ capable of endogenous regeneration has recently gained traction. However, estimated rates of myocyte turnover vary wildly and the underlying mechanisms of cardiac plasticity remain controversial. It is still unclear whether the adult mammalian heart gives birth to new myocytes through proliferation of resident myocytes, through cardiomyogenic differentiation of endogenous progenitors or through both mechanisms. In this review, the authors discuss the cellular origins of postnatal mammalian cardiomyogenesis and touch upon therapeutic strategies that could potentially amplify innate cardiac regeneration. The adult mammalian heart harbors a limited but detectable capacity for spontaneous endogenous regeneration. During normal aging, proliferation of pre-existing cardiomyocytes is the dominant mechanism for generation of new cardiomyocytes. Following myocardial injury, myocyte proliferation increases modestly, but differentiation of endogenous progenitor cells appears to also contribute to cardiomyogenesis (although agreement on the latter point is not universal). Since cardiomyocyte deficiency underlies almost all types of heart disease, development of therapeutic strategies that amplify endogenous regeneration to a clinically-meaningful degree is of utmost importance.

  17. Endogenous Stem Cells Were Recruited by Defocused Low-Energy Shock Wave in Treating Diabetic Bladder Dysfunction.

    Science.gov (United States)

    Jin, Yang; Xu, Lina; Zhao, Yong; Wang, Muwen; Jin, Xunbo; Zhang, Haiyang

    2017-04-01

    Defocused low-energy shock wave (DLSW) has been shown effects on activating mesenchymal stromal cells (MSCs) in vitro. In this study, recruitment of endogenous stem cells was firstly examined as an important pathway during the healing process of diabetic bladder dysfunction (DBD) treated by DLSW in vivo. Neonatal rats received intraperitoneal injection of 5-ethynyl-2-deoxyuridine (EdU) and then DBD rat model was created by injecting streptozotocin. Four weeks later, DLSW treatment was performed. Afterward, their tissues were examined by histology. Meanwhile, adipose tissue-derived stem cells (ADSCs) were treated by DLSW in vitro. Results showed DLSW ameliorated voiding function of diabetic rats by recruiting EdU + Stro-1 + CD34 - endogenous stem cells to release abundant nerve growth factor (NGF) and vascular endothelial growth factor (VEGF). Some EdU + cells overlapped with staining of smooth muscle actin. After DLSW treatment, ADSCs showed higher migration ability, higher expression level of stromal cell-derived factor-1 and secreted more NGF and VEGF. In conclusion, DLSW could ameliorate DBD by recruiting endogenous stem cells. Beneficial effects were mediated by secreting NGF and VEGF, resulting into improved innervation and vascularization in bladder.

  18. Brain Levels of Prostaglandins, Endocannabinoids, and Related Lipids Are Affected by Mating Strategies

    Directory of Open Access Journals (Sweden)

    Jordyn M. Stuart

    2013-01-01

    Full Text Available Background. Endogenous cannabinoids (eCBs are involved in the development and regulation of reproductive behaviors. Likewise, prostaglandins (PGs drive sexual differentiation and initiation of ovulation. Here, we use lipidomics strategies to test the hypotheses that mating immediately activates the biosynthesis and/or metabolism of eCBs and PGs and that specific mating strategies differentially regulate these lipids in the brain. Methods. Lipid extractions and tandem mass spectrometric analysis were performed on brains from proestrous rats that had experienced one of two mating strategies (paced or standard mating and two nonmated groups (chamber exposed and home cage controls. Levels of PGs (PGE2 and PGF2alpha, eCBs (AEA and 2-AG, N-arachidonoyl glycine, and 4 related lipids (4 N-acylethanolamides were measured in olfactory bulb, hypothalamus, hippocampus, thalamus, striatum, midbrain, cerebellum, and brainstem. Results. Overall, levels of these lipids were significantly lower among paced compared to standard mated rats with the most dramatic decreases observed in brainstem, hippocampus, midbrain, and striatum. However, chamber exposed rats had significantly higher levels of these lipids compared to home cage controls and paced mated wherein the hippocampus showed the largest increases. Conclusions. These data demonstrate that mating strategies and exposure to mating arenas influence lipid signaling in the brain.

  19. Early LC3 lipidation induced by d-limonene does not rely on mTOR inhibition, ERK activation and ROS production and it is associated with reduced clonogenic capacity of SH-SY5Y neuroblastoma cells.

    Science.gov (United States)

    Berliocchi, Laura; Chiappini, Carlotta; Adornetto, Annagrazia; Gentile, Debora; Cerri, Silvia; Russo, Rossella; Bagetta, Giacinto; Corasaniti, Maria Tiziana

    2018-02-01

    d-Limonene is a natural monoterpene abundant in Citrus essential oils. It is endowed with several biological activities, including inhibition of carcinogenesis and promotion of tumour regression. Recently, d-limonene has been shown to modulate autophagic markers in vitro at concentrations found in vivo, in clinical pharmacokinetic studies. Autophagy is an intracellular catabolic process serving as both an adaptive metabolic response and a quality control mechanism. Because autophagy defects have been linked to a wide range of human pathologies, including neurodegeneration and cancer, there is a need for new pharmacological tools to control deregulated autophagy. To better understand the effects of d-limonene on autophagy, to identify the molecular mechanisms through which this monoterpene rapidly triggers LC3 lipidation and to evaluate the role for autophagy in long-term effects of d-limonene. Human SH-SY5Y neuroblastoma, HepG2 hepatocellular carcinoma and MCF7 breast cancer cells were used. Endogenous LC3-II levels were evaluated by western blotting. Autophagic flux assay was performed using bafilomycin A1 and chloroquine. Intracellular distribution of LC3 protein was studied by confocal microscopy analysis of LC3B-GFP transduced cells. Expression of lysosomal-membrane protein LAMP-1 was assessed by immunofluorescence analysis. Phosphorylated levels of downstream substrates of mTOR kinase (p70S6 kinase, 4E-BP1, and ULK1) and ERK were analyzed by western blotting. Production of reactive oxygen species (ROS) was assessed by live confocal microscopy of cells loaded with CellROX ® Green Reagent. Clonogenic assay was used to evaluate the ability of treated cells to proliferate and form colonies. LC3 lipidation promoted by d-limonene correlates with autophagosome formation and stimulation of basal autophagy. LC3 lipidation does not rely on inhibition of mTOR kinase, which instead appears to be transiently activated. In addition, d-limonene rapidly activates ERK and

  20. Synergistic effects of high fat feeding and apolipoprotein E deletion on enterocytic amyloid-beta abundance

    Directory of Open Access Journals (Sweden)

    Dhaliwal Satvinder S

    2008-04-01

    Full Text Available Abstract Background Amyloid-β (Aβ, a key protein found in amyloid plaques of subjects with Alzheimer's disease is expressed in the absorptive epithelial cells of the small intestine. Ingestion of saturated fat significantly enhances enterocytic Aβ abundance whereas fasting abolishes expression. Apolipoprotein (apo E has been shown to directly modulate Aβ biogenesis in liver and neuronal cells but it's effect in enterocytes is not known. In addition, apo E modulates villi length, which may indirectly modulate Aβ as a consequence of differences in lipid absorption. This study compared Aβ abundance and villi length in wild-type (WT and apo E knockout (KO mice maintained on either a low-fat or high-fat diet. Wild-type C57BL/6J and apo E KO mice were randomised for six-months to a diet containing either 4% (w/w unsaturated fats, or chow comprising 16% saturated fats and 1% cholesterol. Quantitative immunohistochemistry was used to assess Aβ abundance in small intestinal enterocytes. Apo E KO mice given the low-fat diet had similar enterocytic Aβ abundance compared to WT controls. Results The saturated fat diet substantially increased enterocytic Aβ in WT and in apo E KO mice, however the effect was greater in the latter. Villi height was significantly greater in apo E KO mice than for WT controls when given the low-fat diet. However, WT mice had comparable villi length to apo E KO when fed the saturated fat and cholesterol enriched diet. There was no effect of the high-fat diet on villi length in apo E KO mice. Conclusion The findings of this study are consistent with the notion that lipid substrate availability modulates enterocytic Aβ. Apo E may influence enterocytic lipid availability by modulating absorptive capacity.

  1. Endogenous expression pattern of resolvin D1 in a rat model of self-resolution of lipopolysaccharide-induced acute respiratory distress syndrome and inflammation.

    Science.gov (United States)

    Sun, Wei; Wang, Zai-ping; Gui, Ping; Xia, Weiyi; Xia, Zhengyuan; Zhang, Xing-cai; Deng, Qing-zhu; Xuan, Wei; Marie, Christelle; Wang, Lin-lin; Wu, Qing-ping; Wang, Tingting; Lin, Yun

    2014-11-01

    Resolvin D1 (RvD1), an endogenous lipid mediator derived from docosahexaenoic acid, has been reported to promote a biphasic activity in anti-inflammatory response and regulate inflammatory resolution. The present study aimed to determine the endogenous expression pattern of RvD1 in a rat model of self-resolution of lipopolysaccharide (LPS)-induced acute respiratory distress syndrome (ARDS) and inflammation. The ARDS model was induced by administrating LPS (2mg/kg) via tracheotomy in 138 male Sprague-Dawley rats. At specified time points, lung injury and inflammation were respectively assessed by lung histology and analysis of bronchoalveolar lavage fluid and cytokine levels. The expression of endogenous RvD1 was detected by high performance liquid chromatography and tandem mass spectrometry. The results showed that histological lung injury peaked between 6h (LPS6h) and day 3, followed by recovery over 4-10 days after LPS administration. Lung tissue polymorph nuclear cell (PMN) was significantly increased at LPS6h, and peaked between 6h to day 2. The levels of interleukin (IL)-6 and IL-10 were significantly increased at LPS6h and remained higher over day 10 as compared to baseline. Intriguingly, the endogenous RvD1 expression was decreased gradually during the first 3 days, followed by almost completely recovery over days 9-10. The finding indicated that endogenous RvD1 underwent a decrease in expression followed by gradual increase that was basically coincident with the lung injury recovery in a rat model of self-resolution LPS-induced ARDS and inflammation. Our results may help define the optimal therapeutic window for endogenous RvD1 to prevent or treat LPS-induced ARDS and inflammation. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Characterization of Saccharomyces cerevisiae suppressor mutants devoid of the membrane lipid phosphatidylcholine

    NARCIS (Netherlands)

    Bao, X.

    2018-01-01

    Phosphatidylcholine (PC) is the most abundant membrane lipid in most eukaryotes and considered essential. The yeast double deletion mutant cho2opi3 lacks the methyltransferases converting phosphatidylethanolamine (PE) to PC. As a consequence, the cho2opi3 mutant is a choline auxotroph that relies on

  3. Alterations of plasma lipids in mice via adenoviral-mediated hepatic overexpression of human ABCA1

    NARCIS (Netherlands)

    Wellington, Cheryl L.; Brunham, Liam R.; Zhou, Steven; Singaraja, Roshni R.; Visscher, Henk; Gelfer, Allison; Ross, Colin; James, Erick; Liu, Guoqing; Huber, Mary T.; Yang, Yu-Zhou; Parks, Robin J.; Groen, Albert; Fruchart-Najib, Jamila; Hayden, Michael R.

    2003-01-01

    ATP binding cassette transporter A1 (ABCA1) is a widely expressed lipid transporter essential for the generation of HDL. ABCA1 is particularly abundant in the liver, suggesting that the liver may play a major role in HDL homeostasis. To determine how hepatic ABCA1 affects plasma HDL cholesterol

  4. Significance of sterol structural specificity : desmosterol cannot replace cholesterol in lipid rafts

    NARCIS (Netherlands)

    Vainio, S.; Jansen, Maurice; Koivusalo, M.; Róg, T.; Karttunen, M.E.J.; Vattulainen, I.; Ikonen, E.

    2006-01-01

    Desmosterol is an immediate precursor of cholesterol in the Bloch pathway of sterol synthesis and an abundant membrane lipid in specific cell types. The significance of the difference between the two sterols, an additional double bond at position C24 in the tail of desmosterol, is not known. Here,

  5. Constraints on the sources of branched tetraether membrane lipids in distal marine sediments

    NARCIS (Netherlands)

    Weijers, J.W.H.; Schefuß, E.; Kim, J.-H.; Sinninghe Damsté, J.; Schouten, S.

    2014-01-01

    Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are membrane lipids produced by soil bacteria and occur in near coastal marine sediments as a result of soil organic matter input. Their abundance relative to marine-derived crenarchaeol, quantified in the BIT index, generally decreases

  6. Abundance analyses of thirty cool carbon stars

    International Nuclear Information System (INIS)

    Utsumi, Kazuhiko

    1985-01-01

    The results were previously obtained by use of the absolute gf-values and the cosmic abundance as a standard. These gf-values were found to contain large systematic errors, and as a result, the solar photospheric abundances were revised. Our previous results, therefore, must be revised by using new gf-values, and abundance analyses are extended for as many carbon stars as possible. In conclusion, in normal cool carbon stars heavy metals are overabundant by factors of 10 - 100 and rare-earth elements are overabundant by a factor of about 10, and in J-type cool carbon stars, C 12 /C 13 ratio is smaller, C 2 and CN bands and Li 6708 are stronger than in normal cool carbon stars, and the abundances of s-process elements with respect to Fe are nearly normal. (Mori, K.)

  7. Palaeoceanographic implications of abundance and mean ...

    Indian Academy of Sciences (India)

    Temporal variation in abundance and mean proloculus diameter of the benthic foraminiferal species. Epistominella ... sediments, ice cores, tree rings, corals, etc. are used. ..... Deep-sea foraminifera in the South Atlantic Ocean: Eco- logy and ...

  8. Chinook Abundance - Linear Features [ds181

    Data.gov (United States)

    California Natural Resource Agency — The dataset 'ds181_Chinook_ln' is a product of the CalFish Adult Salmonid Abundance Database. Data in this shapefile are collected from stream sections or reaches...

  9. SWFSC/MMTD: Vaquita Abundance Survey 1997

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 1997, the Southwest Fisheries Science Center (SWFSC) conducted a survey designed to estimate the abundance of vaquita, the Gulf of California harbor porpoise...

  10. Abundance estimation of spectrally similar minerals

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2009-07-01

    Full Text Available This paper evaluates a spectral unmixing method for estimating the partial abundance of spectrally similar minerals in complex mixtures. The method requires formulation of a linear function of individual spectra of individual minerals. The first...

  11. Heavy element abundances of Nova Cygni 1975

    International Nuclear Information System (INIS)

    Ferland, G.J.; Shields, G.A.

    1978-01-01

    McDonald observations of the nebular phase of the outburst of Nova Cygni 1975 are analyzed to measure the abundances of several heavy elements. A new analytical procedure is used to derive the electron density and temperature from the emission line intensities of [O III], [Ne III], and He I observed between days 40 and 120. These physical conditions are used to derive the abundances. We find that Fe has approximately a solar abundance, whereas C, N, O, and Ne are enhanced by factors approx.20 to 100. The enhanced abundance of neon was theoretically unexpected.The derived physical conditions and line intensities are compared with predictions of an equilibrium photoionization model. The model successfully predicts the intensities of He I, [O III], and [Ne III]; but it underestimates the strength of [Ne V] and [Fe VII], which may originate in a mechanically heated ''subcoronal'' line region

  12. Coral lipids and environmental stress.

    Science.gov (United States)

    Harriott, V J

    1993-04-01

    Environmental monitoring of coral reefs is presently limited by difficulties in recognising coral stress, other than by monitoring coral mortality over time. A recent report described an experiment demonstrating that a measured lipid index declined in shaded corals. The technique described might have application in monitoring coral health, with a decline in coral lipid index as an indicator of coral stress. The application of the technique as a practical monitoring tool was tested for two coral species from the Great Barrier Reef. Consistent with the previous results, lipid index for Pocillopora damicornis initially declined over a period of three weeks in corals maintained in filtered seawater in the dark, indicating possible utilization of lipid stored as energy reserves. However, lipid index subsequently rose to near normal levels. In contrast, lipid index of Acropora formosa increased after four weeks in the dark in filtered seawater. The results showed considerable variability in lipid content between samples from the same colony. Results were also found to be dependent on fixation times and sample weight, introducing potential error into the practical application of the technique. The method as described would be unsuitable for monitoring environmental stress in corals, but the search for a practical method to monitor coral health should continue, given its importance in coral reef management.

  13. Lipid composition of human meibum

    Directory of Open Access Journals (Sweden)

    R. Schnetler

    2013-12-01

    Full Text Available The structure and function of meibomian gland lipids in the tear film are highly complex. Evidence shows that the precorneal tear film consists of discrete layers: the inner mucin layer, the middle aqueous layer and the outer lipid layer. In this review we focus on the outer, biphasic lipid layer of the tear film which consists of a ‘thick’ outer, non-polar layer  and a ‘thin’ inner, polar layer. We discuss the main composition of the polar and non-polar lipids within meibum (wax esters, cholesteryl esters, mono-, di- and tri-acylglycerols, ceramides, phospholipids  et cetera. We address the composition of meibomian lipids in subjects suffering from various ocular diseases in comparison with the composition in healthy individuals. Further analysis is needed to determine whether a correlation exists between the etiology of various ocular diseases and the fluctuation on the lipids as well as to establish whether or not tear lipid analysis can be used as a diagnostic tool.

  14. Good abundances from bad spectra - I. Techniques

    Science.gov (United States)

    Jones, J. Bryn; Gilmore, Gerard; Wyse, Rosemary F. G.

    1996-01-01

    Stellar spectra derived from multiple-object fibre-fed spectroscopic radial-velocity surveys, of the type feasible with, among other examples, AUTOFIB, 2dF, HYDRA, NESSIE, and the Sloan survey, differ significantly from those traditionally used for determination of stellar abundances. The spectra tend to be of moderate resolution (around 1A) and signal-to-noise ratio (around 10-20 per resolution element), and cannot usually have reliable continuum shapes determined over wavelength ranges in excess of a few tens of Angstroms. None the less, with care and a calibration of stellar effective temperature from photometry, independent of the spectroscopy, reliable iron abundances can be derived. We have developed techniques to extract true iron abundances and surface gravities from low-signal-to-noise ratio, intermediate-resolution spectra of G-type stars in the 4000-5000A wavelength region. Spectroscopic indices sensitive to iron abundance and gravity are defined from a set of narrow (few-several A wide) wavelength intervals. The indices are calibrated theoretically using synthetic spectra. Given adequate data and a photometrically determined effective temperature, one can derive estimates of the stellar iron abundance and surface gravity. We have also defined a single abundance indicator for the analysis of very low-signal-to-noise ratio spectra; with the further assumption of a value for the stellar surface gravity, this is able to provide useful iron abundance information from spectra having signal-to-noise ratios as low as 10 (1-A elements). The theoretical basis and calibration using synthetic spectra are described in this paper. The empirical calibration of these techniques by application to observational data is described in a separate paper (Jones, Wyse & Gilmore). The technique provides precise iron abundances, with zero-point correct to ~0.1 dex, and is reliable, with typical uncertainties being <~0.2 dex. A derivation of the in situ thick disc metallicity

  15. Chemical Abundances in SFG and DLA

    OpenAIRE

    Schulte-Ladbeck, Regina E.; König, Brigitte; Cherinka, Brian

    2005-01-01

    We investigate the chemical abundances of local star-forming galaxies which cause Damped Lyman Alpha lines. A metallicity versus redshift diagram is constructed, on which the chemical abundances of low-redshift star-forming galaxy populations are compared with those of high-redshift Damped Lyman Alpha systems. We disucss two types of experiments on individual star-forming galaxies. In the first, the Damped Lyman Alpha line is created against an internal ultraviolet light source generated by a...

  16. Composition and abundance of tree regeneration

    Science.gov (United States)

    Todd F. Hutchinson; Elaine Kennedy Sutherland; Charles T. Scott

    2003-01-01

    The composition and abundance of tree seedlings and saplings in the four study areas in southern Ohio were related to soil moisture via a GIS-derived integrated moisture index and to soil texture and fertility. For seedlings, the total abundance of small stems (less than 30 cm tall) was significantly greater on xeric plots (81,987/ha) than on intermediate (54,531/ha)...

  17. Abundance of lithium in Pleiades F stars

    International Nuclear Information System (INIS)

    Pilachowski, C.A.; Booth, J.; Hobbs, L.M.

    1987-01-01

    The abundance of lithium has been determined for 18 stars in the Pleiades cluster with spectral types from A7V to G0V. The pronounced dip in the lithium abundance among the mid-F stars which has been reported for other, older star clusters is not present in the Pleiades. The removal of lithium from the surfaces of middle-F dwarfs therefore occurs principally after about 100 Myr on the main sequence. 25 references

  18. Neuronal Rat Brain Damage Caused by Endogenous and Exogenous Hyperthermia

    Directory of Open Access Journals (Sweden)

    Mustafa Aydın

    2012-03-01

    Full Text Available OBJECTIVE: Hyperthermia may induce pathologic alterations within body systems and organs including brain. In this study, neuronal effects of endogenous and exogenous hyperthermia (41°C were studied in rats. METHODS: The endogenous hyperthermia (41°C was induced by lipopolysaccharide and the exogenous by an (electric heater. Possible neuronal damage was evaluated by examining healthy, apoptotic and necrotic cells, and heat shock proteins (HSP 27, HSP 70 in the cerebral cortex, cerebellum and hypothalamus RESULTS: At cellular level, when all neuronal tissues are taken into account; (i a significant increase in the necrotic cells was observed in the both groups (p0.05. CONCLUSION: The neural tissue of brain can show different degree of response to hyperthermia. But we can conclude that endogenous hyperthermia is more harmful to central nervous system than exogenous hyperthermia

  19. Endogenous induced technical change and the costs of Kyoto

    International Nuclear Information System (INIS)

    Buonanno, Paolo; Carraro, Carlo; Galeotti, Marzio

    2003-01-01

    We present a model for climate change policy analysis which accounts for the possibility that technology evolves endogenously and that technical change can be induced by environmental policy measures. Both the output production technology and the emission-output ratio depend upon a stock of knowledge, which accumulates through R and D activities. Two versions of this model are studied, one with endogenous technical change but exogenous environmental technical change and the other with both endogenous and induced technical change. A third version also captures technological spillover effects. As an application, the model is simulated allowing for trade of pollution permits as specified in the Kyoto Protocol and assessing the implications in terms of cost efficiency, economic growth and R and D efforts of the three different specifications of technical change

  20. Endogenous subclinical hyperthyroidism and cardiovascular system: time to reconsider?

    Science.gov (United States)

    Patanè, Salvatore; Marte, Filippo; Sturiale, Mauro

    2011-05-19

    Subclinical hyperthyroidism is an increasingly recognized entity that is defined as a normal serum free thyroxine and free triiodothyronine levels with a thyroid-stimulating hormone level suppressed below the normal range and usually undetectable. Exogenous sublinical hyperthyroidism is a thyroid metabolic state caused by L-thyroxine administration. Endogenous subclinical hyperthyroidism is a thyroid metabolic state in patients with autonomously functioning thyroid nodule or multinodular goiter, various forms of thyroiditis, in areas with endemic goiter and particularly in elderly subjects. Endogenous subclinical hyperthyroidism is currently the subject of numerous studies and it yet remains controversial particularly as it relates to its treatment and to cardiovascular impact nevertheless established effects have been demonstrated. Recently, acute myocardial infarction without significant coronary stenoses and recurrent acute pulmonary embolism have been reported associated with subclinical hyperthyroidism without L-thyroxine administration. So, it is very important to recognize and to treat promptly also endogenous subclinical hyperthyroidism. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

  1. Lipid Profiling of In Vitro Cell Models of Adipogenic Differentiation: Relationships With Mouse Adipose Tissues.

    Science.gov (United States)

    Liaw, Lucy; Prudovsky, Igor; Koza, Robert A; Anunciado-Koza, Rea V; Siviski, Matthew E; Lindner, Volkhard; Friesel, Robert E; Rosen, Clifford J; Baker, Paul R S; Simons, Brigitte; Vary, Calvin P H

    2016-09-01

    Our objective was to characterize lipid profiles in cell models of adipocyte differentiation in comparison to mouse adipose tissues in vivo. A novel lipid extraction strategy was combined with global lipid profiling using direct infusion and sequential precursor ion fragmentation, termed MS/MS(ALL) . Perirenal and inguinal white adipose tissue and interscapular brown adipose tissues from adult C57BL/6J mice were analyzed. 3T3-L1 preadipocytes, ear mesenchymal progenitor cells, and brown adipose-derived BAT-C1 cells were also characterized. Over 3000 unique lipid species were quantified. Principal component analysis showed that perirenal versus inguinal white adipose tissues varied in lipid composition of triacyl- and diacylglycerols, sphingomyelins, glycerophospholipids and, notably, cardiolipin CL 72:3. In contrast, hexosylceramides and sphingomyelins distinguished brown from white adipose. Adipocyte differentiation models showed broad differences in lipid composition among themselves, upon adipogenic differentiation, and with adipose tissues. Palmitoyl triacylglycerides predominate in 3T3-L1 differentiation models, whereas cardiolipin CL 72:1 and SM 45:4 were abundant in brown adipose-derived cell differentiation models, respectively. MS/MS(ALL) data suggest new lipid biomarkers for tissue-specific lipid contributions to adipogenesis, thus providing a foundation for using in vitro models of adipogenesis to reflect potential changes in adipose tissues in vivo. J. Cell. Biochem. 117: 2182-2193, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. TEA: A CODE CALCULATING THERMOCHEMICAL EQUILIBRIUM ABUNDANCES

    Energy Technology Data Exchange (ETDEWEB)

    Blecic, Jasmina; Harrington, Joseph; Bowman, M. Oliver, E-mail: jasmina@physics.ucf.edu [Planetary Sciences Group, Department of Physics, University of Central Florida, Orlando, FL 32816-2385 (United States)

    2016-07-01

    We present an open-source Thermochemical Equilibrium Abundances (TEA) code that calculates the abundances of gaseous molecular species. The code is based on the methodology of White et al. and Eriksson. It applies Gibbs free-energy minimization using an iterative, Lagrangian optimization scheme. Given elemental abundances, TEA calculates molecular abundances for a particular temperature and pressure or a list of temperature–pressure pairs. We tested the code against the method of Burrows and Sharp, the free thermochemical equilibrium code Chemical Equilibrium with Applications (CEA), and the example given by Burrows and Sharp. Using their thermodynamic data, TEA reproduces their final abundances, but with higher precision. We also applied the TEA abundance calculations to models of several hot-Jupiter exoplanets, producing expected results. TEA is written in Python in a modular format. There is a start guide, a user manual, and a code document in addition to this theory paper. TEA is available under a reproducible-research, open-source license via https://github.com/dzesmin/TEA.

  3. TEA: A CODE CALCULATING THERMOCHEMICAL EQUILIBRIUM ABUNDANCES

    International Nuclear Information System (INIS)

    Blecic, Jasmina; Harrington, Joseph; Bowman, M. Oliver

    2016-01-01

    We present an open-source Thermochemical Equilibrium Abundances (TEA) code that calculates the abundances of gaseous molecular species. The code is based on the methodology of White et al. and Eriksson. It applies Gibbs free-energy minimization using an iterative, Lagrangian optimization scheme. Given elemental abundances, TEA calculates molecular abundances for a particular temperature and pressure or a list of temperature–pressure pairs. We tested the code against the method of Burrows and Sharp, the free thermochemical equilibrium code Chemical Equilibrium with Applications (CEA), and the example given by Burrows and Sharp. Using their thermodynamic data, TEA reproduces their final abundances, but with higher precision. We also applied the TEA abundance calculations to models of several hot-Jupiter exoplanets, producing expected results. TEA is written in Python in a modular format. There is a start guide, a user manual, and a code document in addition to this theory paper. TEA is available under a reproducible-research, open-source license via https://github.com/dzesmin/TEA.

  4. Endogenous induced technical change and the costs of Kyoto

    International Nuclear Information System (INIS)

    Buonanno, Paolo; Carraro, Carlo; Galeotti, M.

    2001-09-01

    Many predictions and conclusions in the climate change literature have been made and drawn on the basis of theoretical analyses and quantitative models that are either static or that allow for simple forms of changes in technology, often along exogenously given time paths. It is therefore not clear a priori whether those conclusions and policy recipes still hold in the more realistic case of endogenously evolving technologies. In this paper, a quantitative tool with the features of an endogenous growth model is presented, which also accounts for the possibility that technical change can be induced by environmental policy measures. Both the output production technology and the emission-output ratio depend upon the stock of knowledge, which accumulates through R and D activities. R and D is thus an additional policy variable that comes into play along with pollution abatement and capital investment. Two versions of this climate model are studied, one with endogenous technical change but exogenous environmental technical change (i.e. no induced technical change) and the other with both endogenous and induced technical change. Hence, in both models technical change evolves endogenously as far as the production technology is concerned, but endogenous environmental (or induced) technical change is only accounted for in the second version. Finally, a third version of the model also captures technological spillover effects. As an application, the three versions of the model are simulated allowing for trade of pollution permits as specified in the Kyoto Protocol and assessing the implications in terms of cost efficiency, economic growth and R and D efforts of the three different specifications of technical change

  5. Alpha Power Modulates Perception Independently of Endogenous Factors

    Directory of Open Access Journals (Sweden)

    Sasskia Brüers

    2018-04-01

    Full Text Available Oscillations are ubiquitous in the brain. Alpha oscillations in particular have been proposed to play an important role in sensory perception. Past studies have shown that the power of ongoing EEG oscillations in the alpha band is negatively correlated with visual outcome. Moreover, it also co-varies with other endogenous factors such as attention, vigilance, or alertness. In turn, these endogenous factors influence visual perception. Therefore, it remains unclear how much of the relation between alpha and perception is indirectly mediated by such endogenous factors, and how much reflects a direct causal influence of alpha rhythms on sensory neural processing. We propose to disentangle the direct from the indirect causal routes by introducing modulations of alpha power, independently of any fluctuations in endogenous factors. To this end, we use white-noise sequences to constrain the brain activity of 20 participants. The cross-correlation between the white-noise sequences and the concurrently recorded EEG reveals the impulse response function (IRF, a model of the systematic relationship between stimulation and brain response. These IRFs are then used to reconstruct rather than record the brain activity linked with new random sequences (by convolution. Interestingly, this reconstructed EEG only contains information about oscillations directly linked to the white-noise stimulation; fluctuations in attention and other endogenous factors may still modulate brain alpha rhythms during the task, but our reconstructed EEG is immune to these factors. We found that the detection of near-perceptual threshold targets embedded within these new white-noise sequences depended on the power of the ~10 Hz reconstructed EEG over parieto-occipital channels. Around the time of presentation, higher power led to poorer performance. Thus, fluctuations in alpha power, induced here by random luminance sequences, can directly influence perception: the relation between

  6. Lipid metabolism in cancer cachexia.

    OpenAIRE

    Mulligan, H. D.; Beck, S. A.; Tisdale, M. J.

    1992-01-01

    The effect of cancer cachexia on the oxidative metabolism of lipids has been studied in mice transplanted either with the MAC16 adenocarcinoma, which induces profound loss of body weight and depletion of lipid stores, or the MAC13 adenocarcinoma, which is the same histological type, but which grows without an effect on host body weight or lipid stores. While oxidation of D-[U-14C]glucose did not differ between animals bearing tumours of either type and non-tumour bearing controls, oxidation o...

  7. Essential fatty acids and lipid mediators. Endocannabinoids

    Directory of Open Access Journals (Sweden)

    G. Caramia

    2012-03-01

    Full Text Available In 1929 Burr and Burr discovered the essential fatty acids omega-6 and omega-3. Since then, researchers have shown a growing interest in polyunsaturated fatty acids (PUFA as precursors of “lipid mediator” molecules, often with opposing effects, prostaglandins, prostacyclins, thromboxanes, leukotrienes, lipossines, resolvines, protectines, maresins that regulate immunity, platelet aggregation, inflammation, etc. They showed that the balance between omega-3 and omega-6 acids has a profound influence on all the body’s inflammatory responses and a raised level of PUFA omega-3 in tissue correlate with a reduced incidence of degenerative cardiovascular disease, some mental illnesses such as depression, and neuro-degenerative diseases such as Alzheimer’s. The CYP-catalyzed epoxidation and hydroxylation of arachidonic acid (AA were established recently as the so-called third branch of AGE cascade. Cytochrome P450 (CYP epoxygenases convert AA to four epoxyeicosatrienoic acid (EET regioisomers, that produce vascular relaxation anti-inflammatory effects on blood vessels and in the kidney, promote angiogenesis, and protect ischemic myocardium and brain. Eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA are accessible to CYP enzymes in the same way as AA. Metabolites derived from EPA include epoxyeicosatetraenoic acids (EETR and hydroxyeicosapentaenoic acids (19- and 20-HEPE, whereas DHA include epoxydocosapentaenoic acids (EDPs hydroxydocosahexaenoic acids (21- and 22-HDoHE. For many of the CYP isoforms, the n-3 PUFAs are the preferred substrates and the available data suggest that some of the vasculo- and cardioprotective effects attributed to dietary n-3 PUFAs may be mediated by CYP-dependent metabolites of EPA and DHA. From AA derives also endocannabinoids like anandamide (N-arachidonoylethanolamine and 2-arachidonoylglycerol, capable of mimicking the pharmacological actions of the active principle of Cannabis sativa preparations such as

  8. Multi-spectral endogenous fluorescence imaging for bacterial differentiation

    Science.gov (United States)

    Chernomyrdin, Nikita V.; Babayants, Margarita V.; Korotkov, Oleg V.; Kudrin, Konstantin G.; Rimskaya, Elena N.; Shikunova, Irina A.; Kurlov, Vladimir N.; Cherkasova, Olga P.; Komandin, Gennady A.; Reshetov, Igor V.; Zaytsev, Kirill I.

    2017-07-01

    In this paper, the multi-spectral endogenous fluorescence imaging was implemented for bacterial differentiation. The fluorescence imaging was performed using a digital camera equipped with a set of visual bandpass filters. Narrowband 365 nm ultraviolet radiation passed through a beam homogenizer was used to excite the sample fluorescence. In order to increase a signal-to-noise ratio and suppress a non-fluorescence background in images, the intensity of the UV excitation was modulated using a mechanical chopper. The principal components were introduced for differentiating the samples of bacteria based on the multi-spectral endogenous fluorescence images.

  9. THE ROLE OF ENTEROSORBENTS IN TREATMENT OF ENDOGENOUS INTOXICATION SYNDROME

    Directory of Open Access Journals (Sweden)

    N. I. Ursova

    2012-01-01

    Full Text Available Usage of enterosorbents in treatment of almost all types of acute and chronic disorders accompanied with endogenous intoxication syndrome takes on special significance. The critical point of endogenous intoxication pathogenesis is dysfunction of microbiocenosis and intestinal barrier. The necessity of enterosorbents usage is very high due to their efficacy, safety and wide availability. Smectite dioctaedric (diosmectite, which has been successfully used in clinical practice for a long period of time, is of an increased interest among the natural enterosorbents. The main quality of diosmectite is its restoration effect on the microbiocenisis and intestinal barrier function, and with a high degree of evidence-based efficacy and safety.

  10. Testing R&D-Based Endogenous Growth Models

    DEFF Research Database (Denmark)

    Kruse-Andersen, Peter Kjær

    2017-01-01

    R&D-based growth models are tested using US data for the period 1953-2014. A general growth model is developed which nests the model varieties of interest. The model implies a cointegrating relationship between multifactor productivity, research intensity, and employment. This relationship...... is estimated using cointegrated VAR models. The results provide evidence against the widely used fully endogenous variety and in favor of the semi-endogenous variety. Forecasts based on the empirical estimates suggest that the slowdown in US productivity growth will continue. Particularly, the annual long...

  11. Hippocampal lipid differences in Alzheimer's disease: a human brain study using matrix-assisted laser desorption/ionization-imaging mass spectrometry.

    Science.gov (United States)

    Mendis, Lakshini H S; Grey, Angus C; Faull, Richard L M; Curtis, Maurice A

    2016-10-01

    Alzheimer's disease (AD), the leading cause of dementia, is pathologically characterized by β-amyloid plaques and tau tangles. However, there is also evidence of lipid dyshomeostasis-mediated AD pathology. Given the structural diversity of lipids, mass spectrometry is a useful tool for studying lipid changes in AD. Although there have been a few studies investigating lipid changes in the human hippocampus in particular, there are few reports on how lipids change in each hippocampal subfield (e.g., Cornu Ammonis [CA] 1-4, dentate gyrus [DG] etc.). Since each subfield has its own function, we postulated that there could be lipid changes that are unique to each. We used matrix-assisted laser desorption/ionization-imaging mass spectrometry to investigate specific lipid changes in each subfield in AD. Data from the hippocampus region of six age- and gender-matched normal and AD pairs were analyzed with SCiLS lab 2015b software (SCiLS GmbH, Germany; RRID:SCR_014426), using an analysis workflow developed in-house. Hematoxylin, eosin, and luxol fast blue staining were used to precisely delineate each anatomical hippocampal subfield. Putative lipid identities, which were consistent with published data, were assigned using MS/MS. Both positively and negatively charged lipid ion species were abundantly detected in normal and AD tissue. While the distribution pattern of lipids did not change in AD, the abundance of some lipids changed, consistent with trends that have been previously reported. However, our results indicated that the majority of these lipid changes specifically occur in the CA1 region. Additionally, there were many lipid changes that were specific to the DG. Matrix-assisted laser desorption/ionization-imaging mass spectrometry and our analysis workflow provide a novel method to investigate specific lipid changes in hippocampal subfields. Future work will focus on elucidating the role that specific lipid differences in each subfield play in AD pathogenesis.

  12. Muscle Lipid Metabolism: Role of Lipid Droplets and Perilipins

    Directory of Open Access Journals (Sweden)

    Pablo Esteban Morales

    2017-01-01

    Full Text Available Skeletal muscle is one of the main regulators of carbohydrate and lipid metabolism in our organism, and therefore, it is highly susceptible to changes in glucose and fatty acid (FA availability. Skeletal muscle is an extremely complex tissue: its metabolic capacity depends on the type of fibers it is made up of and the level of stimulation it undergoes, such as acute or chronic contraction. Obesity is often associated with increased FA levels, which leads to the accumulation of toxic lipid intermediates, oxidative stress, and autophagy in skeletal fibers. This lipotoxicity is one of the most common causes of insulin resistance (IR. In this scenario, the “isolation” of certain lipids in specific cell compartments, through the action of the specific lipid droplet, perilipin (PLIN family of proteins, is conceived as a lifeguard compensatory strategy. In this review, we summarize the cellular mechanism underlying lipid mobilization and metabolism inside skeletal muscle, focusing on the function of lipid droplets, the PLIN family of proteins, and how these entities are modified in exercise, obesity, and IR conditions.

  13. Enhanced dissolved lipid production as a response to the sea surface warming

    Science.gov (United States)

    Novak, Tihana; Godrijan, Jelena; Pfannkuchen, Daniela Marić; Djakovac, Tamara; Mlakar, Marina; Baricevic, Ana; Tanković, Mirta Smodlaka; Gašparović, Blaženka

    2018-04-01

    The temperature increase in oceans reflects on marine ecosystem functioning and surely has consequences on the marine carbon cycle and carbon sequestration. In this study, we examined dissolved lipid, lipid classes and dissolved organic carbon (DOC) production in the northern Adriatic Sea, isolated diatom Chaetoceros pseudocurvisetus batch cultures grown in a wide temperature range (10-30 °C) and in contrasting nutrient regimes, phosphorus (P)-depleted and P-replete conditions. Additionally, lipids and DOC were analyzed in the northern Adriatic (NA) in two stations characterized with different P availability, occupied from February to August 2010 that covered a temperature range from 9.3 to 31.1 °C. To gain insight into factors governing lipid and lipid classes' production in the NA, apart from temperature (T), Chlorophyll a, phytoplankton community abundance and structure, nutrient concentrations were measured together with hydrographic parameters. We found enhanced accumulation of dissolved lipids, particulary glycolipids, with increasing T, especially during the highest in situ temperature. The effect of T on enhanced dissolved lipid release is much more pronounced under P-deplete conditions indicating that oligotrophic regions might be more vulnerable to T rise. Temperature between 25 and 30 °C is a threshold T range for C. pseudocurvisetus, at which a significant part of lipid production is directed toward the dissolved phase. Unlike monocultures, there are multiple factors influencing produced lipid composition, distribution and cycling in the NA that may counteract the T influence. The possible role of enhanced dissolved lipid concentration for carbon sequestration at elevated T is discussed. On the one hand, lipids are buoyant and do not sink, which enhances their retention at the surface layer. In addition, they are surface active, and therefore prone to adsorb on sinking particles, contributing to the C sequestration.

  14. Current trends to comprehend lipid metabolism in diatoms.

    Science.gov (United States)

    Zulu, Nodumo Nokulunga; Zienkiewicz, Krzysztof; Vollheyde, Katharina; Feussner, Ivo

    2018-04-01

    Diatoms are the most dominant phytoplankton species in oceans and they continue to receive a great deal of attention because of their significant contributions in ecosystems and the environment. Due to triacylglycerol (TAG) profiles that are abundant in medium-chain fatty acids, diatoms have emerged to be better feed stocks for biofuel production, in comparison to the commonly studied green microalgal species (chlorophytes). Importantly, diatoms are also known for their high levels of the essential ω3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and are considered to be a promising alternative source of these components. The two most commonly exploited diatoms include Thalassiosira pseudonana and Phaeodactylum tricornutum. Although obvious similarities between diatoms and chlorophytes exist, there are some substantial differences in their lipid metabolism. This review provides an overview on lipid metabolism in diatoms, with P. tricornutum as the most explored model. Special emphasis is placed on the synthesis and incorporation of very long chain ω3 fatty acids into lipids. Furthermore, current approaches including genetic engineering and biotechnological methods aimed at improving and maximizing lipid production in P. tricornutum are also discussed. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Addition of electrophilic lipids to actin alters filament structure

    International Nuclear Information System (INIS)

    Gayarre, Javier; Sanchez, David; Sanchez-Gomez, Francisco J.; Terron, Maria C.; Llorca, Oscar; Perez-Sala, Dolores

    2006-01-01

    Pathophysiological processes associated with oxidative stress lead to the generation of reactive lipid species. Among them, lipids bearing unsaturated aldehyde or ketone moieties can form covalent adducts with cysteine residues and modulate protein function. Through proteomic techniques we have identified actin as a target for the addition of biotinylated analogs of the cyclopentenone prostaglandins 15-deoxy-Δ 12,14 -PGJ 2 (15d-PGJ 2 ) and PGA 1 in NIH-3T3 fibroblasts. This modification could take place in vitro and mapped to the protein C-terminal end. Other electrophilic lipids, like the isoprostane 8-iso-PGA 1 and 4-hydroxy-2-nonenal, also bound to actin. The C-terminal region of actin is important for monomer-monomer interactions and polymerization. Electron microscopy showed that actin treated with 15d-PGJ 2 or 4-hydroxy-2-nonenal formed filaments which were less abundant and displayed shorter length and altered structure. Streptavidin-gold staining allowed mapping of biotinylated 15d-PGJ 2 at sites of filament disruption. These results shed light on the structural implications of actin modification by lipid electrophiles

  16. Nitrogen-deprivation elevates lipid levels in Symbiodinium spp. by lipid droplet accumulation: morphological and compositional analyses.

    Directory of Open Access Journals (Sweden)

    Pei-Luen Jiang

    Full Text Available Stable cnidarian-dinoflagellate (genus Symbiodinium endosymbioses depend on the regulation of nutrient transport between Symbiodinium populations and their hosts. It has been previously shown that the host cytosol is a nitrogen-deficient environment for the intracellular Symbiodinium and may act to limit growth rates of symbionts during the symbiotic association. This study aimed to investigate the cell proliferation, as well as ultrastructural and lipid compositional changes, in free-living Symbiodinium spp. (clade B upon nitrogen (N-deprivation. The cell proliferation of the N-deprived cells decreased significantly. Furthermore, staining with a fluorescent probe, boron dipyrromethane 493/503 (BODIPY 493/503, indicated that lipid contents progressively accumulated in the N-deprived cells. Lipid analyses further showed that both triacylglycerol (TAG and cholesterol ester (CE were drastically enriched, with polyunsaturated fatty acids (PUFA; i.e., docosahexaenoic acid, heneicosapentaenoic acid, and oleic acid became more abundant. Ultrastructural examinations showed that the increase in concentration of these lipid species was due to the accumulation of lipid droplets (LDs, a cellular feature that have previously shown to be pivotal in the maintenance of intact endosymbioses. Integrity of these stable LDs was maintained via electronegative repulsion and steric hindrance possibly provided by their surface proteins. Proteomic analyses of these LDs identified proteins putatively involved in lipid metabolism, signaling, stress response and energy metabolism. These results suggest that LDs production may be an adaptive response that enables Symbiodinium to maintain sufficient cellular energy stores for survival under the N-deprived conditions in the host cytoplasm.

  17. Application of Proteomics and Lipid Studies in Environmental Biotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, Aindrila

    2008-08-12

    The overview of changes in protein levels or states in response to a growth condition, stress, mutation or metabolic engineering is invaluable in understanding the physiology of a microbial system. The lipid profile of the cell is similarly a valuable diagnostic of the cellular response and health, especially in context of survival in a fluctuating environment. To obtain comprehensive cellular models, post-transcriptional cell wide surveys at the levels of proteins and lipids are required. Both these fields have been greatly bolstered by the development of high throughput methods using mass spectrometry. Multiple strategies now exist for the identification of proteins, and numerous workflows to quantify protein abundance have also been developed. Cellular profiling such as these allows us to assess the potential of a microbial system for environmental applications such as bioremediation and bio-energy.

  18. Simultaneous speciation of endogenous and exogenous elements by HPLC/ICP-MS with enriched stable isotopes

    International Nuclear Information System (INIS)

    Suzuki, K.T.

    1996-01-01

    High performance liquid chromatography (HPLC)/inductively coupled argon plasma-mass spectrometry (ICP-MS) was introduced to investigate the distributions of selenium (Se) in biological fluids. The method was to determine both the natural abundance of Se and an enriched stable isotope of Se used as a tracer. The distributions of Se in plasma and in urine specimens were determined in Wistar rats on various Se diets with and without an intravenous injection of 82 Se-selenite. Although the distribution of natural abundance Se (endogenous Se) in the plasma was affected little by the nutritional status of Se, that in the urine gave a Se peak depending on the nutritional status of Se, and the peak was identified as methylselenol. When 82 Se-selenite was injected in excess into rats given three different Se diets (Se-deficient, Se-adequate, Se-excessive), three Se peaks occurred in the HPLC chromatogram of the urine samples, corresponding to selenite, methylselenol and trimethylselenonium ion in the order of elution, and the intensities of the tracer peaks reflected the nutritional status. These results indicate that the HPLC/ICP-MS method is a powerful analytical tool for specifying Se-containing biological constituents, both natural abundance and enriched stable isotopes. Methylselenol in urine is proposed to be a sensitive and Se-specific biological indicator for diagnosing the nutritional status of Se. Furthermore, it was shown that an enriched stable isotope such as 82 Se-selenite was shown to be used for the same purpose, and that 82 Se-methylselenol and 82 Se-trimethylselenonium ion in urine were more sensitive indicators of the Se status of the rats. (author)

  19. [Participation of final products of lipid peroxidation in the anticancer mechanism of ionizing radiation and radiomimetic cytostatics].

    Science.gov (United States)

    Przybyszewski, W M

    2001-01-01

    This review reports the evidence for the participation of final products of lipid peroxidation in the anticancer mechanism of ionising radiation and radiomimetic cytostatics. Processes of lipid peroxidation occur endogenously in response to oxidative stress and great diversity of reactive metabolites is formed. However, direct observation of radical reaction in pathophysiology of cells, tissues and organs is limited technically. Most investigations focused on the indirect assessment of their final products, aldehydes. The peroxidative breakdown of polyunsaturated fatty acids is believed to be involved in the regulation of cell division, and antitumor effect through biochemical and genetic processes.

  20. Blood lipids and prostate cancer

    DEFF Research Database (Denmark)

    Bull, Caroline J; Bonilla, Carolina; Holly, Jeff M P

    2016-01-01

    Genetic risk scores were used as unconfounded instruments for specific lipid traits (Mendelian randomization) to assess whether circulating lipids causally influence prostate cancer risk. Data from 22,249 prostate cancer cases and 22,133 controls from 22 studies within the international PRACTICAL...... into logistic regression models to estimate the presence (and direction) of any causal effect of each lipid trait on prostate cancer risk. There was weak evidence for an association between the LDL genetic score and cancer grade: the odds ratio (OR) per genetically instrumented standard deviation (SD) in LDL.......95, 3.00; P = 0.08). The rs12916-T variant in 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) was inversely associated with prostate cancer (OR: 0.97; 95% CI: 0.94, 1.00; P = 0.03). In conclusion, circulating lipids, instrumented by our genetic risk scores, did not appear to alter prostate cancer risk...

  1. Clustering in the stellar abundance space

    Science.gov (United States)

    Boesso, R.; Rocha-Pinto, H. J.

    2018-03-01

    We have studied the chemical enrichment history of the interstellar medium through an analysis of the n-dimensional stellar abundance space. This work is a non-parametric analysis of the stellar chemical abundance space. The main goal is to study the stars from their organization within this abundance space. Within this space, we seek to find clusters (in a statistical sense), that is, stars likely to share similar chemo-evolutionary history, using two methods: the hierarchical clustering and the principal component analysis. We analysed some selected abundance surveys available in the literature. For each sample, we labelled the group of stars according to its average abundance curve. In all samples, we identify the existence of a main enrichment pattern of the stars, which we call chemical enrichment flow. This flow is set by the structured and well-defined mean rate at which the abundances of the interstellar medium increase, resulting from the mixture of the material ejected from the stars and stellar mass-loss and interstellar medium gas. One of the main results of our analysis is the identification of subgroups of stars with peculiar chemistry. These stars are situated in regions outside of the enrichment flow in the abundance space. These peculiar stars show a mismatch in the enrichment rate of a few elements, such as Mg, Si, Sc and V, when compared to the mean enrichment rate of the other elements of the same stars. We believe that the existence of these groups of stars with peculiar chemistry may be related to the accretion of planetary material on to stellar surfaces or may be due to production of the same chemical element by different nucleosynthetic sites.

  2. Bioactive Lipids in Dairy Fat

    DEFF Research Database (Denmark)

    Hellgren, Lars; Nordby, Pernille

    2017-01-01

    Milk fat is the most important energy source for the newborn infant beside its important role as energy source, milk fat also contain a range of bioactive lipids, that potentially can modulate the immune response and metabolic regulation in the child. In this chapter we review the literature on b...... on bioactive dairy fatty acids: conjugated linoleic acid, branched chained and odd chained fatty acids, as well as bioactive complex lipids such as sphingomyelin and gangliosides....

  3. [Lipids of Aureobasidium (Pullularia) pullulans].

    Science.gov (United States)

    Elinov, N P; Iurlova, N A; Efimova, T P

    1975-01-01

    Fractional composition of free and bound lipids was studied in Aureobasidium (Pullularia) pullulans 8 by preparative TLC on Silufol. Bound lipids contained a fraction (27.76 +/- 0.5%) of dark brown colour, similar to melanin. The composition of fatty acids was studied by GLC. The following fatty acids were identified and determined quantitatively: C12:0, C14:0, C15:0, C16:0, C18:0, C18:1+C15:2. The following fatty acids predominated in free and bound lipids: C16:0, C18:1+C18:2. The ratio between unsaturated and saturated fatty acids in all fractions of free and bound lipids was more than unity. The following parameters were determined for lipids; ester number (173.89 and 178.53); iodine number (44.1 and 33.10), and saponification number (181.17 and 206.03) (the values are given for free and bound lipids, respectively).

  4. Bracken: estimating species abundance in metagenomics data

    Directory of Open Access Journals (Sweden)

    Jennifer Lu

    2017-01-01

    Full Text Available Metagenomic experiments attempt to characterize microbial communities using high-throughput DNA sequencing. Identification of the microorganisms in a sample provides information about the genetic profile, population structure, and role of microorganisms within an environment. Until recently, most metagenomics studies focused on high-level characterization at the level of phyla, or alternatively sequenced the 16S ribosomal RNA gene that is present in bacterial species. As the cost of sequencing has fallen, though, metagenomics experiments have increasingly used unbiased shotgun sequencing to capture all the organisms in a sample. This approach requires a method for estimating abundance directly from the raw read data. Here we describe a fast, accurate new method that computes the abundance at the species level using the reads collected in a metagenomics experiment. Bracken (Bayesian Reestimation of Abundance after Classification with KrakEN uses the taxonomic assignments made by Kraken, a very fast read-level classifier, along with information about the genomes themselves to estimate abundance at the species level, the genus level, or above. We demonstrate that Bracken can produce accurate species- and genus-level abundance estimates even when a sample contains multiple near-identical species.

  5. Abundance of sea kraits correlates with precipitation.

    Directory of Open Access Journals (Sweden)

    Harvey B Lillywhite

    Full Text Available Recent studies have shown that sea kraits (Laticauda spp.--amphibious sea snakes--dehydrate without a source of fresh water, drink only fresh water or very dilute brackish water, and have a spatial distribution of abundance that correlates with freshwater sites in Taiwan. The spatial distribution correlates with sites where there is a source of fresh water in addition to local precipitation. Here we report six years of longitudinal data on the abundance of sea kraits related to precipitation at sites where these snakes are normally abundant in the coastal waters of Lanyu (Orchid Island, Taiwan. The number of observed sea kraits varies from year-to-year and correlates positively with previous 6-mo cumulative rainfall, which serves as an inverse index of drought. Grouped data for snake counts indicate that mean abundance in wet years is nearly 3-fold greater than in dry years, and this difference is significant. These data corroborate previous findings and suggest that freshwater dependence influences the abundance or activity of sea kraits on both spatial and temporal scales. The increasing evidence for freshwater dependence in these and other marine species have important implications for the possible impact of climate change on sea snake distributions.

  6. Seismological measurement of solar helium abundance

    International Nuclear Information System (INIS)

    Vorontsov, S.V.; Pamyatnykh, A.A.

    1991-01-01

    The internal structure and evolution of the Sun depends on its chemical composition, particularly the helium abundance. In addition, the helium abundance in the solar envelope is thought to represent the protosolar value, making it a datum of cosmological significance. Spectroscopic measurements of the helium abundance are uncertain, and the most reliable estimates until now have come from the calibration of solar evolutionary models. The frequencies of solar acoustic oscillations are sensitive, however, to the behaviour of the speed of sound in the Sun's helium ionization zone, which allows a helioseismological determination of the helium abundance. Sound-speed inversion of helioseismological data can be used for this purpose, but precise frequency measurements of high-degree oscillation modes are needed. Here we describe a new approach based on an analysis of the phase shift of acoustic waves of intermediate-degree modes. From the accurate intermediate-mode data now available, we obtain a helium mass fraction Y=0.25±0.01 in the solar convection zone, significantly smaller than the value Y=0.27-0.29 predicted by recent solar evolutionary models. The discrepancy indicates either that initial helium abundance was reduced in the envelope by downward diffusion or that the protosolar value was lower than currently accepted. (author)

  7. Deuterium abundance, from ultraviolet to visible

    International Nuclear Information System (INIS)

    Hebrard, Guillaume

    2000-01-01

    In the frame of the standard Big Bang model, the primordial abundance of deuterium is the most sensitive to the baryonic density of the Universe. It was synthesized only during the primordial nucleosynthesis few minutes after the Big Bang and no other standard mechanism is able to produce any further significant amount. On the contrary, since deuterium is burned up within stars, its abundance D/H decreases along cosmic evolution. Thus, D/H measurements constrain Big Bang and galactic chemical evolution models. There are three samples of deuterium abundances: primordial, proto-solar and interstellar. Each of them is representative of a given epoch, respectively about 15 Gyrs past, 4.5 Gyrs past and present epoch. Although the evolution of the deuterium abundance seems to be qualitatively understood, the measurements show some dispersion. Present thesis works are linked to deuterium interstellar abundance measurements. Such measurements are classically obtained from spectroscopic observations of the hydrogen and deuterium Lyman series in absorption in the ultraviolet spectral range, using space observatories. Results presented here were obtained with the Hubble Space Telescope and FUSE, which has recently been launched. Simultaneously, a new way to observe deuterium has been proposed, in the visible spectral range from ground-based telescopes. This has led to the first detections and the identification of the deuterium Balmer series, in emission in HII regions, using CFHT and VLT telescopes. (author) [fr

  8. Liver X receptor antagonist reduces lipid formation and increases glucose metabolism in myotubes from lean, obese and type 2 diabetic individuals

    DEFF Research Database (Denmark)

    Kase, E T; Thoresen, G H; Westerlund, S

    2007-01-01

    AIMS/HYPOTHESIS: Liver X receptors (LXRs) play important roles in lipid and carbohydrate metabolism. The purpose of the present study was to evaluate effects of the endogenous LXR agonist 22-R-hydroxycholesterol (22-R-HC) and its stereoisomer 22-S-hydroxycholesterol (22-S-HC), in comparison...... with the synthetic agonist T0901317 on lipid and glucose metabolism in human skeletal muscle cells (myotubes). METHODS: Myotubes established from lean and obese control volunteers and from obese type 2 diabetic volunteers were treated with LXR ligands for 4 days. Lipid and glucose metabolisms were studied...... with labelled precursors, and gene expression was analysed using real-time PCR. RESULTS: Treatment with T0901317 increased lipogenesis (de novo lipid synthesis) and lipid accumulation in myotubes, this increase being more pronounced in myotubes from type 2 diabetic volunteers than from lean volunteers...

  9. Place branding, embeddedness and endogenous rural development : Four European cases

    NARCIS (Netherlands)

    Donner, Mechthild; Horlings, Lummina; Fort, Fatiha; Vellema, Sietze

    2017-01-01

    This article deals with place branding on the regional scale, in the rural context of food and tourism networks in Europe. Place branding is linked to the concepts of endogenous rural development, territory and embeddedness, by analysing how the valorisation of specific rural assets takes shape. The

  10. Endogenous technological change with leisure-dependent utility.

    NARCIS (Netherlands)

    Hek, de P.A.

    1999-01-01

    This paper investigates the effect of introducing leisure-dependent utility into two models of endogenous technological change. Due to the flexibility in the labour supply the dynamics of the models change significantly. It is shown that if agents attach enough value to leisure in comparison to

  11. The potential of endogenous learning approaches to gender and ...

    African Journals Online (AJOL)

    USER

    An analysis of gender inclusive law making in Rwanda's parliament and ... Public Partnerships, and endogenous knowledge research through ... and women, the co-sponsorship of a draft bill by four men and four women in ..... relations, and working relationships between project stakeholders in gender institutions in Africa.

  12. Endogenous factors that relate to the eating habits of adolescents ...

    African Journals Online (AJOL)

    The aim in this research was to determine how endogenous factors such as gender, intelligence, self-concept, and personality relate to the eating habits of adolescents. An empirical investigation was conducted using 340 secondary school learners, 162 boys and 178 girls. From the results it appeared that girls tend to have ...

  13. Quantitative live imaging of endogenous DNA replication in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Andrew Burgess

    Full Text Available Historically, the analysis of DNA replication in mammalian tissue culture cells has been limited to static time points, and the use of nucleoside analogues to pulse-label replicating DNA. Here we characterize for the first time a novel Chromobody cell line that specifically labels endogenous PCNA. By combining this with high-resolution confocal time-lapse microscopy, and with a simplified analysis workflow, we were able to produce highly detailed, reproducible, quantitative 4D data on endogenous DNA replication. The increased resolution allowed accurate classification and segregation of S phase into early-, mid-, and late-stages based on the unique subcellular localization of endogenous PCNA. Surprisingly, this localization was slightly but significantly different from previous studies, which utilized over-expressed GFP tagged forms of PCNA. Finally, low dose exposure to Hydroxyurea caused the loss of mid- and late-S phase localization patterns of endogenous PCNA, despite cells eventually completing S phase. Taken together, these results indicate that this simplified method can be used to accurately identify and quantify DNA replication under multiple and various experimental conditions.

  14. The two faces of endogenous DNA editing enzymes: Promoting ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The two faces of endogenous DNA editing enzymes: Promoting gene mutations as well as genome repair. Type B lymphocytes are a specific type of white blood cell within our immune system. They produce and export antibodies which seek out, attach to, and neutralize microbes and toxins. A unique way that B ...

  15. Proteomics investigation of endogenous S-nitrosylation in Arabidopsis

    International Nuclear Information System (INIS)

    Fares, Abasse; Rossignol, Michel; Peltier, Jean-Benoît

    2011-01-01

    Highlights: ► Identification and quantification of nitrosothiols. ► A first dataset of endogenously nitrosylated cysteines in Arabidopsis cells. ► Nitrosothiols display apolar motifs not located in close vicinity of cysteines. ► Salt stress alters the endogenous nitrosylation of specific cysteines in Arabidopsis. -- Abstract: S-Nitrosylation emerges as an important protein modification in many processes. However, most data were obtained at the protein level after addition of a NO donor, particularly in plants where information about the cysteines nitrosylated in these proteins is scarce. An adapted work-flow, combining the classical biotin switch method and labeling with isotope-coded affinity tags (ICAT), is proposed. Without addition of NO donor, a total of 53 endogenous nitrosocysteines was identified in Arabidopsis cells, in proteins belonging to all cell territories, including membranes, and covering a large panel of functions. This first repertoire of nitrosothiols in plants enabled also preliminary structural description. Three apolar motifs, not located in close vicinity of cysteines and accounting for half the dataset, were detected and are proposed to complement nitrosylation prediction algorithms, poorly trained with plant data to date. Analysis of changes induced by a brief salt stress showed that NaCl modified the nitrosylation level of a small proportion of endogenously nitrosylated proteins and did not concern all nitrosothiols in these proteins. The possible role of some NO targets in the response to salt stress was discussed.

  16. Chromatographic analysis of endogenous retinoids in tissues and serum

    NARCIS (Netherlands)

    Schmidt, C.K.; Brouwer, A.; Nau, H.

    2003-01-01

    We present a reliable, highly sensitive, and versatile method for the simultaneous determination of endogenous polar (acidic) and apolar (retinol, retinal, and retinyl esters) retinoids in various biological matrices. Following a single liquid extraction of retinoids from tissues or plasma with

  17. [Exploration of the Essence of "Endogenous Turbidity" in Chinese Medicine].

    Science.gov (United States)

    Fan, Xin-rong; Tang, Nong; Ji, Yun-xi; Zhang, Yao-zhong; Jiang, Li; Huang, Gui-hua; Xie, Sheng; Li, Liu-mei; Song, Chun-hui; Ling, Jiang-hong

    2015-08-01

    The essence of endogenous turbidity in Chinese medicine (CM) is different from cream, fat, phlegm, retention, damp, toxicity, and stasis. Along with the development of modern scientific technologies and biology, researches on the essence of endogenous turbidity should keep pace with the time. Its material bases should be defined and new connotation endowed at the microscopic level. The essence of turbidity lies in abnormal functions of zang-fu organs. Sugar, fat, protein, and other nutrient substances cannot be properly decomposed, but into semi-finished products or intermediate metabolites. They are inactive and cannot participate in normal material syntheses and decomposition. They cannot be transformed to energy metabolism, but also cannot be synthesized as executive functioning of active proteins. If they cannot be degraded by autophagy-lysosome or ubiquitin-prosome into glucose, fatty acids, amino acids, and other basic nutrients to be used again, they will accumulate inside the human body and become endogenous turbidity. Therefore, endogenous turbidity is different from final metabolites such as urea, carbon dioxide, etc., which can transform vital qi. How to improve the function of zang-fu organs, enhance its degradation by autophagy-lysosome or ubiquitin-prosome is of great significance in normal operating of zang-fu organs and preventing the emergence and progress of related diseases.

  18. Do endogenous and exogenous action control compete for perception?

    Science.gov (United States)

    Pfister, Roland; Heinemann, Alexander; Kiesel, Andrea; Thomaschke, Roland; Janczyk, Markus

    2012-04-01

    Human actions are guided either by endogenous action plans or by external stimuli in the environment. These two types of action control seem to be mediated by neurophysiologically and functionally distinct systems that interfere if an endogenously planned action suddenly has to be performed in response to an exogenous stimulus. In this case, the endogenous representation has to be deactivated first to give way to the exogenous system. Here we show that interference of endogenous and exogenous action control is not limited to motor-related aspects but also affects the perception of action-related stimuli. Participants associated two actions with contingent sensory effects in learning blocks. In subsequent test blocks, preparing one of these actions specifically impaired responding to the associated effect in an exogenous speeded detection task, yielding a blindness-like effect for arbitrary, learned action effects. In accordance with the theory of event coding, this finding suggests that action planning influences perception even in the absence of any physical similarities between action and to-be-perceived stimuli.

  19. Endogeneous price leadership in a duopoly: equal products, unequal technology

    NARCIS (Netherlands)

    Dastidar, K.G.; Furth, D.

    2005-01-01

    In the present paper we study endogenous price leadership in the context of a homogeneous product Bertrand duopoly model in which the firms have different, strictly convex cost functions. In such a framework it is well known that a simultaneous move price choice game does not have an equilibrium in

  20. An endogenous standard, radioisotopic ratio method in NAA

    International Nuclear Information System (INIS)

    Byrne, A.R.; Dermelj, M.

    1997-01-01

    A derivative form of NAA is proposed which is based on the use of an endogenous internal standard of already known concentration in the sample. If a comparator with a known ratio of the determinand and endogenous standard are co-irradiated with the sample, the determinand concentration is derived in terms of the endogenous standard concentration and the activity ratios of the two induced nuclides in the sample and comparator. As well as eliminating the sample mass and greatly reducing errors caused by pulse pile-up and geometrical differences, it was shown that in the radiochemical mode, if the endogenous standard is chosen so that the induced activity is radioisotopic with that from the determinand, the radiochemical yield is also eliminated and the risk non-achievement of isotopic exchange greatly reduced. The method is demonstrated with good results on reference materials for the determination of I, Mn and Ni. The advantages and disadvantages of this approach are discussed. It is suggested that it may be of application in quality control and in extending the range of certified elements in reference materials. (author)

  1. Endogenous opioid peptides as neurotransmitters in the rat hippocampus

    International Nuclear Information System (INIS)

    Neumaier, J.F.

    1989-01-01

    The role of endogenous opioid peptides as neurotransmitters in the rat hippocampus was investigated by using extracellular recording and radioligand binding techniques in the hippocampal slice preparation. Synaptic conductances from endogenously released opioid peptides have been difficult to detect. This problem was approach by designing a novel assay of opioid peptide release, in which release was detected by measuring binding competition between endogenous opioids and added radioligand. Membrane depolarization displaced [ 3 H]-diprenorphine binding in a transient, calcium-dependent, and peptidase-sensitive manner. Autoradiographic localization of the sites of [ 3 H]-diprenorphine binding displacement showed that significant opioid peptide release and receptor occupancy occurred in each major subregion of the hippocampal slices. This assay method can not be used to define optimal electrical stimulation conditions for releasing endogenous opioids. The binding displacement method was extended to the study of the sigma receptor. Depolarization of hippocampal slices was found to reduce the binding of the sigma-selective radioligand [ 3 H]-ditolylguanidine in a transient and calcium-dependent manner with no apparent direct effects on sigma receptor affinity

  2. Endogenous heparin levels in the controlled asthmatic patient ...

    African Journals Online (AJOL)

    Background. Since heparin possesses anti-inflammatory properties, it is hypothesised that asthmatic patients have decreased levels of circulating heparin compared with healthy individuals. Design. We compared endogenous heparin levels in controlled asthmatic patients (53 adults) from the Asthma Clinic at ...

  3. Antidiabetic and Plasma Endogenous Antioxidant Activity of alstonia ...

    African Journals Online (AJOL)

    Alstonia boonei is a well-known plant of medicinal value but its effect on endogenous plasma antioxidant in diabetes remains unknown. Thus, need to investigate the effects of the methanolic extract of the plant on plasma bilirubin and uric acid level in alloxan induced diabetes rabbits. Twenty five rabbits divided into five ...

  4. Endogenous Losses of Nitrogen and Protein Requirement for ...

    African Journals Online (AJOL)

    Four fistulated and four intact West African dwarf wether sheep, maintained on hay and concentrate supplements were used for a study of metabolic faecal nitrogen (MEN) and endogenous urinary nitrogen (EUN). The composition of the faecal losses was examined. The values obtained enabled calculation of nitrogen ...

  5. Endogenous circadian regulation of carbon dioxide exchange in terrestrial ecosystems

    Science.gov (United States)

    Victor Resco de Dios; Michael L. Goulden; Kiona Ogle; Andrew D. Richardson; David Y. Hollinger; Eric A. Davidson; Josu G. Alday; Greg A. Barron-Gafford; Arnaud Carrara; Andrew S. Kowalski; Walt C. Oechel; Borja R. Reverter; Russell L. Scott; Ruth K. Varner; Ruben Diaz-Sierra; Jose M. Moreno

    2012-01-01

    It is often assumed that daytime patterns of ecosystem carbon assimilation are mostly driven by direct physiological responses to exogenous environmental cues. Under limited environmental variability, little variation in carbon assimilation should thus be expected unless endogenous plant controls on carbon assimilation, which regulate photosynthesis in time, are active...

  6. Changes in endogenous hormone contents of pear stock ( Pyrus ...

    African Journals Online (AJOL)

    In this study, changes in endogenous hormone contents of pear stock seeds during cold stratification were investigated. Abscisic acid (ABA) content decreased with increase in the periods of stratification of pear stock seeds. However, gibberellic acid (GA) and indole-3-acetic acid (IAA) contents of Pyrus betulaefolia and ...

  7. Cinnamaldehyde promotes root branching by regulating endogenous hydrogen sulfide.

    Science.gov (United States)

    Xue, Yan-Feng; Zhang, Meng; Qi, Zhong-Qiang; Li, You-Qin; Shi, Zhiqi; Chen, Jian

    2016-02-01

    Cinnamaldehyde (CA) has been widely applied in medicine and food preservation. However, whether and how CA regulates plant physiology is largely unknown. To address these gaps, the present study investigated the beneficial effect of CA on root branching and its possible biochemical mechanism. The lateral root (LR) formation of pepper seedlings could be markedly induced by CA at specific concentrations without any inhibitory effect on primary root (PR) growth. CA could induce the generation of endogenous hydrogen sulfide (H2S) by increasing the activity of L-cysteine desulfhydrase in roots. By fluorescently tracking endogenous H2S in situ, it could be clearly observed that H2S accumulated in the outer layer cells of the PR where LRs emerge. Sodium hydrosulfide (H2S donor) treatment induced LR formation, while hypotaurine (H2S scavenger) showed an adverse effect. The addition of hypotaurine mitigated the CA-induced increase in endogenous H2S level, which in turn counteracted the inducible effect of CA on LR formation. CA showed great potential in promoting LR formation, which was mediated by endogenous H2S. These results not only shed new light on the application of CA in agriculture but also extend the knowledge of H2S signaling in the regulation of root branching. © 2015 Society of Chemical Industry.

  8. Expression and function of endogenous retroviruses in the placenta.

    Science.gov (United States)

    Denner, Joachim

    2016-01-01

    Although the expression of endogenous retroviruses in the placenta of numerous species was observed a long time ago, their physiological function during gestation was demonstrated only very recently. Expression of retroviral envelope proteins, also called syncytins, in the placenta allows generation of the multinuclear syncytiotrophoblast as an outer cellular layer of the placenta by fusion of the trophoblast cells. This fusion process is crucial for the development of the placenta and for successful pregnancy. It is still unclear whether the immunosuppressive properties of the transmembrane envelope protein of the endogenous retroviruses expressed in the placenta contribute to immunosuppression to prevent the rejection of the semiallotransplant embryo. The presence of placenta cells expressing retroviral envelope proteins surrounded by immune cells deep in the maternal tissue supports an immunosuppressive function. It is important to emphasize that during evolution different species utilized ('enslaved') different endogenous retroviruses and that two or more endogenous retroviruses are involved in placentogenesis in each species. © 2016 APMIS. Published by John Wiley & Sons Ltd.

  9. Endogenous mitigation of H2S inside of the landfills.

    Science.gov (United States)

    Fang, Yuan; Zhong, Zhong; Shen, Dongsheng; Du, Yao; Xu, Jing; Long, Yuyang

    2016-02-01

    Vast quantities of hydrogen sulfide (H2S) emitted from landfill sites require urgent disposal. The current study focused on source control and examined the migration and conversion behavior of sulfur compounds in two lab-scale simulated landfills with different operation modes. It aimed to explore the possible strategies and mechanisms for H2S endogenous mitigation inside of landfills during decomposition. It was found that the strength of H2S emissions from the landfill sites was dependent on the municipal solid waste (MSW) degradation speed and vertical distribution of sulfide. Leachate recirculation can shorten both the H2S influence period and pollution risk to the surrounding environment. H2S endogenous mitigation may be achieved by chemical oxidation, biological oxidation, adsorption, and/or precipitation in different stages. Migration and conversion mainly affected H2S release behavior during the initial stabilization phase in the landfill. Microbial activities related to sulfur, nitrogen, and iron can further promote H2S endogenous mitigation during the high reducing phase. Thus, H2S endogenous mitigation can be effectively enhanced via control of the aforementioned processes.

  10. Origin of ores of endogeneous uranium ore deposits

    International Nuclear Information System (INIS)

    Kasanskij, V.I.; Laverov, N.P.; Tugarinov, A.I.

    1976-01-01

    The consideration mainly includes those endogenous uranium ore deposits of which more exact data are available, such as precambrian ones in areas of proto-activated old platforms, deposits of palaeozoic fold areas, and mesozoic deposits in areas of tectonic-magnetic activation. Their genesis and typical characters are mentioned and conclusions on the general distribution of the deposits are drawn. (author)

  11. Inhibition of endogenous lactate turnover with lactate infusion in humans

    International Nuclear Information System (INIS)

    Searle, G.L.; Feingold, K.R.; Hsu, F.S.; Clark, O.H.; Gertz, E.W.; Stanley, W.C.

    1989-01-01

    The extent to which lactate infusion may inhibit endogenous lactate production, though previously considered, has never been critically assessed. To examine this proposition, single injection tracer methodology (U- 14 C Lactate) has been used for the estimation of lactate kinetics in 12 human subjects under basal conditions and with the infusion of sodium lactate. The basal rate of lactate turnover was measured on a day before the study with lactate infusion, and averaged 63.7 + 5.5 mg/kg/h. Six of these individuals received a stable lactate infusion at an approximate rate of 160 mg/kg/h, while the remaining six individuals were infused at the approximate rate of 100 mg/kg/h. It has been found that stable lactate infused at rates approximating 160 mg/kg/h consistently produced a complete inhibition of endogenous lactate production. Infusion of lactate at 100 mg/kg/h caused a lesser and more variable inhibition of endogenous lactate production (12% to 64%). In conclusion, lactate infusion significantly inhibits endogenous lactate production

  12. School system evaluation by value added analysis under endogeneity.

    Science.gov (United States)

    Manzi, Jorge; San Martín, Ernesto; Van Bellegem, Sébastien

    2014-01-01

    Value added is a common tool in educational research on effectiveness. It is often modeled as a (prediction of a) random effect in a specific hierarchical linear model. This paper shows that this modeling strategy is not valid when endogeneity is present. Endogeneity stems, for instance, from a correlation between the random effect in the hierarchical model and some of its covariates. This paper shows that this phenomenon is far from exceptional and can even be a generic problem when the covariates contain the prior score attainments, a typical situation in value added modeling. Starting from a general, model-free definition of value added, the paper derives an explicit expression of the value added in an endogeneous hierarchical linear Gaussian model. Inference on value added is proposed using an instrumental variable approach. The impact of endogeneity on the value added and the estimated value added is calculated accurately. This is also illustrated on a large data set of individual scores of about 200,000 students in Chile.

  13. Inflation Targeting and Liquidity Traps under Endogenous Credibility

    NARCIS (Netherlands)

    Hommes, C.; Lustenhouwer, J.

    2015-01-01

    We derive policy implications for an inflation targeting central bank, who's credibility is endogenous and depends on its past ability to achieve its targets. We do this in a New Keynesian framework with heterogeneous agents and boundely rational expectations. Our assumptions about expectation

  14. RELIABLE ASSAYS FOR DETERMINING ENDOGENOUS COMPONENTS OF HUMAN MILK

    Science.gov (United States)

    Healthy women from 18-38 years old (N=25) fasted for several hours and twice donated blood and milk (postpartum 2-7 weeks and 3-4 months) for the EPA's Methods Advancement for Milk Analysis study, a pilot for the National Children's Study (NCS). Endogenous components were chosen...

  15. Conceptual Understanding of Multiplicative Properties through Endogenous Digital Game Play

    Science.gov (United States)

    Denham, Andre

    2012-01-01

    This study purposed to determine the effect of an endogenously designed instructional game on conceptual understanding of the associative and distributive properties of multiplication. Additional this study sought to investigate if performance on measures of conceptual understanding taken prior to and after game play could serve as predictors of…

  16. Place branding, embeddedness and endogenous rural development : Four European cases

    NARCIS (Netherlands)

    Donner, Mechthild; Horlings, Lummina; Fort, Fatiha; Vellema, Sietze

    This article deals with place branding on the regional scale, in the rural context of food and tourism networks in Europe. Place branding is linked to the concepts of endogenous rural development, territory and embeddedness, by analysing how the valorisation of specific rural assets takes shape. The

  17. Novel endogenous angiogenesis inhibitors and their therapeutic potential.

    Science.gov (United States)

    Rao, Nithya; Lee, Yu Fei; Ge, Ruowen

    2015-10-01

    Angiogenesis, the formation of new blood vessels from the pre-existing vasculature is essential for embryonic development and tissue homeostasis. It also plays critical roles in diseases such as cancer and retinopathy. A delicate balance between pro- and anti-angiogenic factors ensures normal physiological homeostasis. Endogenous angiogenesis inhibitors are proteins or protein fragments that are formed in the body and have the ability to limit angiogenesis. Many endogenous angiogenesis inhibitors have been discovered, and the list continues to grow. Endogenous protein/peptide inhibitors are relatively less toxic, better tolerated and have a lower risk of drug resistance, which makes them attractive as drug candidates. In this review, we highlight ten novel endogenous protein angiogenesis inhibitors discovered within the last five years, including ISM1, FKBPL, CHIP, ARHGAP18, MMRN2, SOCS3, TAp73, ZNF24, GPR56 and JWA. Although some of these proteins have been well characterized for other biological functions, we focus on their new and specific roles in angiogenesis inhibition and discuss their potential for therapeutic application.

  18. Borderline Personality Disorder: A Dysregulation of the Endogenous Opioid System?

    Science.gov (United States)

    Bandelow, Borwin; Schmahl, Christian; Falkai, Peter; Wedekind, Dirk

    2010-01-01

    The neurobiology of borderline personality disorder (BPD) remains unclear. Dysfunctions of several neurobiological systems, including serotoninergic, dopaminergic, and other neurotransmitter systems, have been discussed. Here we present a theory that alterations in the sensitivity of opioid receptors or the availability of endogenous opioids…

  19. Uncertainty and endogenous technical change in climate policy models

    International Nuclear Information System (INIS)

    Baker, Erin; Shittu, Ekundayo

    2008-01-01

    Until recently endogenous technical change and uncertainty have been modeled separately in climate policy models. In this paper, we review the emerging literature that considers both these elements together. Taken as a whole the literature indicates that explicitly including uncertainty has important quantitative and qualitative impacts on optimal climate change technology policy. (author)

  20. Competition Between Endogenous and Exogenous Orienting of Visual Attention

    Science.gov (United States)

    Berger, Andrea; Henik, Avishai; Rafal, Robert

    2005-01-01

    The relation between reflexive and voluntary orienting of visual attention was investigated with 4 experiments: a simple detection task, a localization task, a saccade toward the target task, and a target identification task in which discrimination difficulty was manipulated. Endogenous and exogenous orienting cues were presented in each trial and…