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Sample records for altered selenoprotein synthesis

  1. Altered hippocampus synaptic function in selenoprotein P deficient mice

    Directory of Open Access Journals (Sweden)

    Peters Melinda M

    2006-09-01

    Full Text Available Abstract Selenium is an essential micronutrient that function through selenoproteins. Selenium deficiency results in lower concentrations of selenium and selenoproteins. The brain maintains it's selenium better than other tissues under low-selenium conditions. Recently, the selenium-containing protein selenoprotein P (Sepp has been identified as a possible transporter of selenium. The targeted disruption of the selenoprotein P gene (Sepp1 results in decreased brain selenium concentration and neurological dysfunction, unless selenium intake is excessive However, the effect of selenoprotein P deficiency on the processes of memory formation and synaptic plasticity is unknown. In the present studies Sepp1(-/- mice and wild type littermate controls (Sepp1(+/+ fed a high-selenium diet (1 mg Se/kg were used to characterize activity, motor coordination, and anxiety as well as hippocampus-dependent learning and memory. Normal associative learning, but disrupted spatial learning was observed in Sepp1(-/- mice. In addition, severe alterations were observed in synaptic transmission, short-term plasticity and long-term potentiation in hippocampus area CA1 synapses of Sepp1(-/- mice on a 1 mg Se/kg diet and Sepp1(+/+ mice fed a selenium-deficient (0 mg Se/kg diet. Taken together, these data suggest that selenoprotein P is required for normal synaptic function, either through presence of the protein or delivery of required selenium to the CNS.

  2. Deletion of Selenoprotein P Results in Impaired Function of Parvalbumin Interneurons and Alterations in Fear Learning and Sensorimotor Gating

    OpenAIRE

    Pitts, Matthew W.; Raman, Arjun V; Hashimoto, Ann C; Todorovic, Cedomir; Nichols, Robert A.; Berry, Marla J.

    2012-01-01

    One of the primary lines of defense against oxidative stress is the selenoprotein family, a class of proteins that contain selenium in the form of the 21st amino acid, selenocysteine. Within this class of proteins, Selenoprotein P (Sepp1) is unique, as it contains multiple selenocysteine residues and is postulated to act in selenium transport. Recent findings have demonstrated that neuronal selenoprotein synthesis is required for the development of parvalbumin (PV)-interneurons, a class of GA...

  3. Selenoprotein-Transgenic Chlamydomonas reinhardtii

    Directory of Open Access Journals (Sweden)

    Jiazuan Ni

    2013-02-01

    Full Text Available Selenium (Se deficiency is associated with the occurrence of many diseases. However, excessive Se supplementation, especially with inorganic Se, can result in toxicity. Selenoproteins are the major forms of Se in vivo to exert its biological function. Expression of those selenoproteins, especially with the application of a newly developed system, is thus very important for studying the mechanism of Se in nutrition. The use of Chlamydomonas reinhardtii (C. reinhardtii as a biological vector to express an heterogeneous protein is still at the initial stages of development. In order to investigate the possibility of using this system to express selenoproteins, human 15-KDa selenoprotein (Sep15, a small but widely distributed selenoprotein in mammals, was chosen for the expression platform test. Apart from the wild-type human Sep15 gene fragment, two Sep15 recombinants were constructed containing Sep15 open reading frame (ORF and the selenocysteine insertion sequence (SECIS element from either human Sep15 or C. reinhardtii selenoprotein W1, a highly expressed selenoprotein in this alga. Those Sep15-containing plasmids were transformed into C. reinhardtii CC-849 cells. Results showed that Sep15 fragments were successfully inserted into the nuclear genome and expressed Sep15 protein in the cells. The transgenic and wild-type algae demonstrated similar growth curves in low Se culture medium. To our knowledge, this is the first report on expressing human selenoprotein in green alga.

  4. Cloning of human 15ku selenoprotein gene from H9 T cells

    Institute of Scientific and Technical Information of China (English)

    Ke-Jun Nan; Chun-Li Li; Yong-Chang Wei; Chen-Guang Sui; Zhao Jing; Hai-Xia Qin; Li-Jun Zhao; Bo-Rong Pan

    2003-01-01

    AIM: To clone human 15ku selenoprotein gene.METHODS: H9 human T cells were cultured in RPMI1640medium supplemented with 100 mL/L fetal calf serum. mRNA was isolated from the cells. cDNA library was constructed by RT-PCR. The human 15ku selenoprotein gene was obtained by PCR and cloned into T vector and sequenced.RESULTS: A unique cDNA fragment about 1 244 bp was obtained. Sequence analysis identified an open reading frame within the cDNA. The gene had an in-frame TGA, which encoded selenocysteine (Sec), and a 3′-UTR SECIS element,which was required for synthesis of selenoprotein. The predicted protein molecular mass was about 15ku (162residues). The result was identical with human liver 15ku selenoprotein gene published in Genbank.CONCLUSION: Human 15ku selenoprotein gene can be successfully obtained from T cell line.

  5. Selenoprotein P is the essential selenium transporter for bones.

    Science.gov (United States)

    Pietschmann, Nicole; Rijntjes, Eddy; Hoeg, Antonia; Stoedter, Mette; Schweizer, Ulrich; Seemann, Petra; Schomburg, Lutz

    2014-05-01

    Selenium (Se) plays an important role in bone physiology as best reflected by Kashin-Beck disease, an endemic Se-dependent osteoarthritis. Bone development is delayed in children with mutations in SECIS binding protein 2 (SBP2), a central factor for selenoprotein biosynthesis. Circulating selenoprotein P (SePP) is positively associated with bone turnover in humans, yet its function for bone homeostasis is not known. We have analysed murine models of altered Se metabolism. Most of the known selenoprotein genes and factors needed for selenoprotein biosynthesis are expressed in bones. Bone Se is not associated with the mineral but exclusively with the organic matrix. Genetic ablation of Sepp-expression causes a drastic decline in serum (25-fold) but only a mild reduction in bone (2.5-fold) Se concentrations. Cell-specific expression of a SePP transgene in hepatocytes efficiently restores bone Se levels in Sepp-knockout mice. Of the two known SePP receptors, Lrp8 was detected in bones while Lrp2 was absent. Interestingly, Lrp8 mRNA concentrations were strongly increased in bones of Sepp-knockout mice likely in order to counteract the developing Se deficiency. Our data highlight SePP as the essential Se transporter to bones, and suggest a novel feedback mechanism for preferential uptake of Se in Se-deprived bones, thereby contributing to our understanding of hepatic osteodystrophy and the consistent bone phenotype observed in subjects with inherited selenoprotein biosynthesis mutations. PMID:24626785

  6. Selenoprotein-Transgenic Chlamydomonas reinhardtii

    OpenAIRE

    Jiazuan Ni; Zhangli Hu; Jing Tian; Qintang Hou; Qiong Liu; Shi Qiu

    2013-01-01

    Selenium (Se) deficiency is associated with the occurrence of many diseases. However, excessive Se supplementation, especially with inorganic Se, can result in toxicity. Selenoproteins are the major forms of Se in vivo to exert its biological function. Expression of those selenoproteins, especially with the application of a newly developed system, is thus very important for studying the mechanism of Se in nutrition. The use of Chlamydomonas reinhardtii (C. reinhardtii) as a biological vector ...

  7. Selenoproteins-What unique properties can arise with selenocysteine in place of cysteine?

    Energy Technology Data Exchange (ETDEWEB)

    Arner, Elias S.J., E-mail: Elias.Arner@ki.se [Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm (Sweden)

    2010-05-01

    The defining entity of a selenoprotein is the inclusion of at least one selenocysteine (Sec) residue in its sequence. Sec, the 21st naturally occurring genetically encoded amino acid, differs from its significantly more common structural analog cysteine (Cys) by the identity of a single atom: Sec contains selenium instead of the sulfur found in Cys. Selenium clearly has unique chemical properties that differ from sulfur, but more striking are perhaps the similarities between the two elements. Selenium was discovered by Joens Jacob Berzelius, a renowned Swedish scientist instrumental in establishing the institution that would become Karolinska Institutet. Written at the occasion of the bicentennial anniversary of Karolinska Institutet, this mini review focuses on the unique selenium-derived properties that may potentially arise in a protein upon the inclusion of Sec in place of Cys. With 25 human genes encoding selenoproteins and in total several thousand selenoproteins yet described in nature, it seems likely that the presence of that single selenium atom of Sec should convey some specific feature, thereby explaining the existence of selenoproteins in spite of demanding and energetically costly Sec-specific synthesis machineries. Nonetheless, most, if not all, of the currently known selenoproteins are also found as Cys-containing non-selenoprotein orthologues in other organisms, wherefore any potentially unique properties of selenoproteins are yet a matter of debate. The pK{sub a} of free Sec (approximately 5.2) being significantly lower than that of free Cys (approximately 8.5) has often been proposed as one of the unique features of Sec. However, as discussed herein, this pK{sub a} difference between Sec and Cys can hardly provide an evolutionary pressure for maintenance of selenoproteins. Moreover, the typically 10- to 100-fold lower enzymatic efficiencies of Sec-to-Cys mutants of selenoprotein oxidoreductases, are also weak arguments for the overall existence

  8. Selenoproteins-What unique properties can arise with selenocysteine in place of cysteine?

    Science.gov (United States)

    Arnér, Elias S J

    2010-05-01

    The defining entity of a selenoprotein is the inclusion of at least one selenocysteine (Sec) residue in its sequence. Sec, the 21st naturally occurring genetically encoded amino acid, differs from its significantly more common structural analog cysteine (Cys) by the identity of a single atom: Sec contains selenium instead of the sulfur found in Cys. Selenium clearly has unique chemical properties that differ from sulfur, but more striking are perhaps the similarities between the two elements. Selenium was discovered by Jöns Jacob Berzelius, a renowned Swedish scientist instrumental in establishing the institution that would become Karolinska Institutet. Written at the occasion of the bicentennial anniversary of Karolinska Institutet, this mini review focuses on the unique selenium-derived properties that may potentially arise in a protein upon the inclusion of Sec in place of Cys. With 25 human genes encoding selenoproteins and in total several thousand selenoproteins yet described in nature, it seems likely that the presence of that single selenium atom of Sec should convey some specific feature, thereby explaining the existence of selenoproteins in spite of demanding and energetically costly Sec-specific synthesis machineries. Nonetheless, most, if not all, of the currently known selenoproteins are also found as Cys-containing non-selenoprotein orthologues in other organisms, wherefore any potentially unique properties of selenoproteins are yet a matter of debate. The pK(a) of free Sec (approximately 5.2) being significantly lower than that of free Cys (approximately 8.5) has often been proposed as one of the unique features of Sec. However, as discussed herein, this pK(a) difference between Sec and Cys can hardly provide an evolutionary pressure for maintenance of selenoproteins. Moreover, the typically 10- to 100-fold lower enzymatic efficiencies of Sec-to-Cys mutants of selenoprotein oxidoreductases, are also weak arguments for the overall existence of

  9. Selenoproteins-What unique properties can arise with selenocysteine in place of cysteine?

    International Nuclear Information System (INIS)

    The defining entity of a selenoprotein is the inclusion of at least one selenocysteine (Sec) residue in its sequence. Sec, the 21st naturally occurring genetically encoded amino acid, differs from its significantly more common structural analog cysteine (Cys) by the identity of a single atom: Sec contains selenium instead of the sulfur found in Cys. Selenium clearly has unique chemical properties that differ from sulfur, but more striking are perhaps the similarities between the two elements. Selenium was discovered by Joens Jacob Berzelius, a renowned Swedish scientist instrumental in establishing the institution that would become Karolinska Institutet. Written at the occasion of the bicentennial anniversary of Karolinska Institutet, this mini review focuses on the unique selenium-derived properties that may potentially arise in a protein upon the inclusion of Sec in place of Cys. With 25 human genes encoding selenoproteins and in total several thousand selenoproteins yet described in nature, it seems likely that the presence of that single selenium atom of Sec should convey some specific feature, thereby explaining the existence of selenoproteins in spite of demanding and energetically costly Sec-specific synthesis machineries. Nonetheless, most, if not all, of the currently known selenoproteins are also found as Cys-containing non-selenoprotein orthologues in other organisms, wherefore any potentially unique properties of selenoproteins are yet a matter of debate. The pKa of free Sec (approximately 5.2) being significantly lower than that of free Cys (approximately 8.5) has often been proposed as one of the unique features of Sec. However, as discussed herein, this pKa difference between Sec and Cys can hardly provide an evolutionary pressure for maintenance of selenoproteins. Moreover, the typically 10- to 100-fold lower enzymatic efficiencies of Sec-to-Cys mutants of selenoprotein oxidoreductases, are also weak arguments for the overall existence of

  10. Evolution of selenoproteins in the metazoan

    Directory of Open Access Journals (Sweden)

    Jiang Liang

    2012-09-01

    Full Text Available Abstract Background The selenocysteine (Sec containing proteins, selenoproteins, are an important group of proteins present throughout all 3 kingdoms of life. With the rapid progression of selenoprotein research in the post-genomic era, application of bioinformatics methods to the identification of selenoproteins in newly sequenced species has become increasingly important. Although selenoproteins in human and other vertebrates have been investigated, studies of primitive invertebrate selenoproteomes are rarely reported outside of insects and nematodes. Result A more integrated view of selenoprotein evolution was constructed using several representative species from different evolutionary eras. Using a SelGenAmic-based selenoprotein identification method, 178 selenoprotein genes were identified in 6 invertebrates: Amphimedon queenslandica, Trichoplax adhaerens, Nematostella vectensis, Lottia gigantean, Capitella teleta, and Branchiostoma floridae. Amphioxus was found to have the most abundant and variant selenoproteins of any animal currently characterized, including a special selenoprotein P (SelP possessing 3 repeated Trx-like domains and Sec residues in the N-terminal and 2 Sec residues in the C-terminal. This gene structure suggests the existence of two different strategies for extension of Sec numbers in SelP for the preservation and transportation of selenium. In addition, novel eukaryotic AphC-like selenoproteins were identified in sponges. Conclusion Comparison of various animal species suggests that even the most primitive animals possess a selenoproteome range and variety similar to humans. During evolutionary history, only a few new selenoproteins have emerged and few were lost. Furthermore, the massive loss of selenoproteins in nematodes and insects likely occurred independently in isolated partial evolutionary branches.

  11. Mutations in the selenocysteine insertion sequence–binding protein 2 gene lead to a multisystem selenoprotein deficiency disorder in humans

    OpenAIRE

    Schoenmakers, Erik; Agostini, Maura; Mitchell, Catherine; Schoenmakers, Nadia; Papp, Laura; Rajanayagam, Odelia; Padidela, Raja; Ceron-Gutierrez, Lourdes; Doffinger, Rainer; Prevosto, Claudia; Luan, Jian’an; Montano, Sergio; Lu, Jun; Castanet, Mireille; Clemons, Nick

    2010-01-01

    Selenium, a trace element that is fundamental to human health, is incorporated into some proteins as selenocysteine (Sec), generating a family of selenoproteins. Sec incorporation is mediated by a multiprotein complex that includes Sec insertion sequence–binding protein 2 (SECISBP2; also known as SBP2). Here, we describe subjects with compound heterozygous defects in the SECISBP2 gene. These individuals have reduced synthesis of most of the 25 known human selenoproteins, resulting in a comple...

  12. Selenoprotein P – Expression, Functions, and Roles in Mammals

    OpenAIRE

    Raymond F Burk; Hill, Kristina E.

    2009-01-01

    Selenoprotein P (Sepp1) is a secreted protein that is made up of 2 domains. The larger N-terminal domain contains 1 selenocysteine residue in a redox motif and the smaller C-terminal domain contains the other 9 selenocysteines. Sepp1 isoforms of varying length occur but quantitation of them has not been achieved. Hepatic synthesis of Sepp1 affects whole-body selenium content and the liver is the source of most plasma Sepp1. ApoER2, a member of the lipoprotein receptor family, binds Sepp1 and ...

  13. Mutations in the selenocysteine insertion sequence–binding protein 2 gene lead to a multisystem selenoprotein deficiency disorder in humans

    Science.gov (United States)

    Schoenmakers, Erik; Agostini, Maura; Mitchell, Catherine; Schoenmakers, Nadia; Papp, Laura; Rajanayagam, Odelia; Padidela, Raja; Ceron-Gutierrez, Lourdes; Doffinger, Rainer; Prevosto, Claudia; Luan, Jian’an; Montano, Sergio; Lu, Jun; Castanet, Mireille; Clemons, Nick; Groeneveld, Matthijs; Castets, Perrine; Karbaschi, Mahsa; Aitken, Sri; Dixon, Adrian; Williams, Jane; Campi, Irene; Blount, Margaret; Burton, Hannah; Muntoni, Francesco; O’Donovan, Dominic; Dean, Andrew; Warren, Anne; Brierley, Charlotte; Baguley, David; Guicheney, Pascale; Fitzgerald, Rebecca; Coles, Alasdair; Gaston, Hill; Todd, Pamela; Holmgren, Arne; Khanna, Kum Kum; Cooke, Marcus; Semple, Robert; Halsall, David; Wareham, Nicholas; Schwabe, John; Grasso, Lucia; Beck-Peccoz, Paolo; Ogunko, Arthur; Dattani, Mehul; Gurnell, Mark; Chatterjee, Krishna

    2010-01-01

    Selenium, a trace element that is fundamental to human health, is incorporated into some proteins as selenocysteine (Sec), generating a family of selenoproteins. Sec incorporation is mediated by a multiprotein complex that includes Sec insertion sequence–binding protein 2 (SECISBP2; also known as SBP2). Here, we describe subjects with compound heterozygous defects in the SECISBP2 gene. These individuals have reduced synthesis of most of the 25 known human selenoproteins, resulting in a complex phenotype. Azoospermia, with failure of the latter stages of spermatogenesis, was associated with a lack of testis-enriched selenoproteins. An axial muscular dystrophy was also present, with features similar to myopathies caused by mutations in selenoprotein N (SEPN1). Cutaneous deficiencies of antioxidant selenoenzymes, increased cellular ROS, and susceptibility to ultraviolet radiation–induced oxidative damage may mediate the observed photosensitivity. Reduced levels of selenoproteins in peripheral blood cells were associated with impaired T lymphocyte proliferation, abnormal mononuclear cell cytokine secretion, and telomere shortening. Paradoxically, raised ROS in affected subjects was associated with enhanced systemic and cellular insulin sensitivity, similar to findings in mice lacking the antioxidant selenoenzyme glutathione peroxidase 1 (GPx1). Thus, mutation of SECISBP2 is associated with a multisystem disorder with defective biosynthesis of many selenoproteins, highlighting their role in diverse biological processes. PMID:21084748

  14. Time course of selenium labelling of selenoproteins in Se adequate and Se deficient rats

    International Nuclear Information System (INIS)

    Column chromatography has identified a number of new selenoproteins. To discriminate between selenoproteins and Se-binding proteins, the authors used SDS-PAGE to remove loosely-bound 75Se and thus quantitate 75Se-labelled selenoproteins. +Se (Wayne Lab Blox) and -Se rats (75Se]selenite (0.5 ug Se) and sacrificed 1, 3, 24 or 72 hr later. 75Se-proteins in various tissues were separated according to subunit molecular weight by SDS-PAGE, and gel slices were counted to determine 75Se labelling. In +Se plasma, a 55kDa protein was the major 75Se-protein at 1 and 3 hr; gluathione peroxidase (GSH-Px, 20kDa subunit) was labelled at 24 and 72 hr. In -Se plasma the 55kDa 75Se-protein was 4-fold higher and GSH-Px 75Se was reduced. In +Se liver cytosol GSH-Px was the major 75Se- species at all times; GSH-Px 75Se was greater in +Se than -Se liver. In +Se and -Se testes, a 17kDa protein was labelled increasingly over 72 hr. Notably, a number of additional 75Se-proteins were observed, but cycloheximide pretreatment completely blocked 75Se-labelling of all selenoproteins in both +Se and -Se rats. This study shows that SDS-PAGE can be used to resolve and quantify a number of selenoproteins in addition to GSH-Px. The cycloheximide inhibition of labelling further suggests that these species are true selenoproteins that are labelled only during or immediately after protein synthesis

  15. A Method for Identification of Selenoprotein Genes in Archaeal Genomes

    Institute of Scientific and Technical Information of China (English)

    Mingfeng Li; Yanzhao Huang; Yi Xiao

    2009-01-01

    The genetic codon UGA has a dual function: serving as a terminator and encoding selenocysteine. However, most popular gene annotation programs only take it as a stop signal, resulting in misannotation or completely missing selenoprotein genes. We developed a computational method named Asec-Prediction that is specific for the prediction of archaeal selenoprotein genes. To evaluate its effectiveness, we first applied it to 14 archaeal genomes with previously known selenoprotein genes, and Asec-Prediction identified all reported selenoprotein genes without redundant results. When we applied it to 12 archaeal genomes that had not been researched for selenoprotein genes, Asec-Prediction detected a novel selenoprotein gene in Methanosarcina acetivorans. Further evidence was also collected to support that the predicted gene should be a real selenoprotein gene. The result shows that Asec-Prediction is effective for the prediction of archaeal selenoprotein genes.

  16. Selenoprotein P in colitis-associated carcinoma

    Science.gov (United States)

    Short, Sarah P.; Whitten-Barrett, Caitlyn; Williams, Christopher S.

    2016-01-01

    ABSTRACT Patients with inflammatory bowel disease are often deficient in micronutrients such as selenium and have an increased risk of colon cancer. We tested whether the selenium transport protein, selenoprotein P, could modify colitis-associated cancer. Our results indicate that global SEPP1 haploinsufficiency augments tumorigenesis and mediates oxidative damage in the intestine. PMID:27314080

  17. Alterations in gastric mucin synthesis by Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    James C, Byrd; Robert S, Bresalier

    2000-01-01

    AIM To determine the role of Helicobacter pylori in altering gastric mucin synthesis and define how thprocess relates to H. pylori-related diseases.METHODS Analyses of human gastric tissues using immunohistochemistry and in situ hybridizatiodocument the role of H. pylori in altering the composition and distribution of gastric mucins.RESULTS These data indicate a decrease in the product of the MUC5 (MUC5AC) gene and aberraexpression of MUC6 in the surface epithelium of H. pylori-infected patients. A normal pattern was restorby H. pylori eradication. Inhibition of mucin synthesis including MUC5AC and MUCl mucins by H. pvlohas been established in vitro using biochemical and Western blot analyses. This effect is not due to inhibitiof glycosylation, but results from inhibition of synthesis of mucin core structures. In vitro experiments usiinhibitors of mucin synthesis indicate that cell surface mucins decrease adhesion of H. pylori to gastepithelial cells.CONCLUSION Inhibition of mucin synthesis by H. pylori in vivo can disrupt the protective mucous layand facilitate bacterial adhesion, which may lead to increased inflammation in thc gastric epithelium.

  18. Ebola viral selenoproteins:a metallomics analysis

    Institute of Scientific and Technical Information of China (English)

    Somsri; Wiwanitkit; Viroj; Wiwanitkit

    2015-01-01

    Ebola virus infection is the present public health problem.The trend of worldwide epidemic becomes the serious consideration for this infection.The Ebola virus infection has main clinical manifestation as acute febrile illness with hemorrhagic episode.The problem of hemostatic disturbance can be seen.Focusing on the palhophysiology.selenium plays an important role in the blood clotting regulation.The study on the selenoprotein of the Ebola virus can be useful for further understanding on the pathology of the infection.Here,the authors use metallomics analysis for assessment of Ebola virus genome.According to this study,the selenoprotein portion within Ebola virus genome can be detected at position 1046-1115.

  19. Selenoprotein P in der kolorektalen Karzinogenese

    OpenAIRE

    Eußner, Ursula

    2003-01-01

    DNA-Schädigungen durch Sauerstoff-Radikale werden als bedeutende pathogene Faktoren der kolorektalen Karzinogenese angesehen. Als ein antioxidativer Schutzmechanismus im Gastrointestinaltrakt wird u. a. das Selenoprotein P vermutet, dessen mRNA-Expression in Kolonadenomen im Vergleich zu angrenzender gesunder Darmmukosa stark vermindert nachgewiesen wurde. Interessant ist zudem die Lokalisation des SePP-Gens auf Chromosom 5q31 in der Nähe des APC-Gens, eines schon in frühen Stadien der kolore...

  20. Selenium and Selenoprotein Deficiencies Induce Widespread Pyogranuloma Formation in Mice, while High Levels of Dietary Selenium Decrease Liver Tumor Size Driven by TGFα

    Science.gov (United States)

    Zhong, Nianxin; Ward, Jerrold M.; Perella, Christine M.; Hoffmann, Victoria J.; Rogers, Keith; Combs, Gerald F.; Schweizer, Ulrich; Merlino, Glenn; Gladyshev, Vadim N.; Hatfield, Dolph L.

    2013-01-01

    Changes in dietary selenium and selenoprotein status may influence both anti- and pro-cancer pathways, making the outcome of interventions different from one study to another. To characterize such outcomes in a defined setting, we undertook a controlled hepatocarcinogenesis study involving varying levels of dietary selenium and altered selenoprotein status using mice carrying a mutant (A37G) selenocysteine tRNA transgene (TrsptG37) and/or a cancer driver TGFα transgene. The use of TrsptG37 altered selenoprotein expression in a selenoprotein and tissue specific manner and, at sufficient dietary selenium levels, separate the effect of diet and selenoprotein status. Mice were maintained on diets deficient in selenium (0.02 ppm selenium) or supplemented with 0.1, 0.4 or 2.25 ppm selenium or 30 ppm triphenylselenonium chloride (TPSC), a non-metabolized selenium compound. TrsptG37 transgenic and TGFα/TrsptG37 bi-transgenic mice subjected to selenium-deficient or TPSC diets developed a neurological phenotype associated with early morbidity and mortality prior to hepatocarcinoma development. Pathology analyses revealed widespread disseminated pyogranulomatous inflammation. Pyogranulomas occurred in liver, lungs, heart, spleen, small and large intestine, and mesenteric lymph nodes in these transgenic and bi-transgenic mice. The incidence of liver tumors was significantly increased in mice carrying the TGFα transgene, while dietary selenium and selenoprotein status did not affect tumor number and multiplicity. However, adenoma and carcinoma size and area were smaller in TGFα transgenic mice that were fed 0.4 and 2.25 versus 0.1 ppm of selenium. Thus, selenium and selenoprotein deficiencies led to widespread pyogranuloma formation, while high selenium levels inhibited the size of TGFα–induced liver tumors. PMID:23460847

  1. Selenoprotein P. A selenium-rich extracellular glycoprotein.

    Science.gov (United States)

    Burk, R F; Hill, K E

    1994-10-01

    Selenoprotein P is a glycoprotein that has been purified from rat and human plasma. In selenium-replete rats it contains 65% of the plasma selenium and its concentration is 25-30 mg protein/L. In selenium-deficient rats its concentration is life of 75Se in selenoprotein P is 3 to 4 h, indicating a rapid turnover. Purified rat selenoprotein P contains 7.5 +/- 1 selenium atoms per molecule as selenocysteine. The sequence of the cloned cDNA predicts 10 selenocysteine residues, which suggests that the protein in plasma is a modification of the predicted one. Deduced amino acid sequence identity between rats and humans is 72%. The 3' untranslated region of selenoprotein P cDNA contains two predicted stem loops of the type essential for selenocysteine incorporation. Northern analysis indicates that selenoprotein P is expressed by many tissues. Hepatic selenoprotein P mRNA level, but not its transcription, decreases during selenium deficiency. The decrease is less than the decrease of glutathione peroxidase mRNA, however. Selenoprotein P is postulated to serve as an extracellular oxidant defense because its presence correlates with selenium protection of selenium-deficient rats against diquat-induced lipid peroxidation and liver necrosis. More research will be required to test this hypothesis and to establish the biochemical function of selenoprotein P. PMID:7931697

  2. Relaxation of selective constraints causes independent selenoprotein extinction in insect genomes.

    Directory of Open Access Journals (Sweden)

    Charles E Chapple

    Full Text Available BACKGROUND: Selenoproteins are a diverse family of proteins notable for the presence of the 21st amino acid, selenocysteine. Until very recently, all metazoan genomes investigated encoded selenoproteins, and these proteins had therefore been believed to be essential for animal life. Challenging this assumption, recent comparative analyses of insect genomes have revealed that some insect genomes appear to have lost selenoprotein genes. METHODOLOGY/PRINCIPAL FINDINGS: In this paper we investigate in detail the fate of selenoproteins, and that of selenoprotein factors, in all available arthropod genomes. We use a variety of in silico comparative genomics approaches to look for known selenoprotein genes and factors involved in selenoprotein biosynthesis. We have found that five insect species have completely lost the ability to encode selenoproteins and that selenoprotein loss in these species, although so far confined to the Endopterygota infraclass, cannot be attributed to a single evolutionary event, but rather to multiple, independent events. Loss of selenoproteins and selenoprotein factors is usually coupled to the deletion of the entire no-longer functional genomic region, rather than to sequence degradation and consequent pseudogenisation. Such dynamics of gene extinction are consistent with the high rate of genome rearrangements observed in Drosophila. We have also found that, while many selenoprotein factors are concomitantly lost with the selenoproteins, others are present and conserved in all investigated genomes, irrespective of whether they code for selenoproteins or not, suggesting that they are involved in additional, non-selenoprotein related functions. CONCLUSIONS/SIGNIFICANCE: Selenoproteins have been independently lost in several insect species, possibly as a consequence of the relaxation in insects of the selective constraints acting across metazoans to maintain selenoproteins. The dispensability of selenoproteins in insects may

  3. Dexamethasone-induced selenoprotein S degradation is required for adipogenesis

    OpenAIRE

    Kim, Choon Young; Kim, Kee-Hong

    2013-01-01

    Although adipogenesis is associated with induction of endoplasmic reticulum (ER) stress, the role of selenoprotein S (SEPS1), an ER resident selenoprotein known to regulate ER stress and ER-associated protein degradation, is unknown. We found an inverse relationship between SEPS1 level in adipose tissue and adiposity in mice. While SEPS1 expression was increased during adipogenesis, a markedly reduced SEPS1 protein level was found in the early phase of adipogenesis due to dexamethasone (DEX)-...

  4. Einfluss von Selenoprotein P auf die intestinale Tumorigenese im Mausmodell

    OpenAIRE

    Michaelis, Marten

    2009-01-01

    Das essentielle Spurenelement Selen (Se) wird als einziges Spurenelement über den genetischen Code als Bestandteil der 21. proteinogene Aminosäure Selenocystein (SeCys) in eine kleine Gruppe von Proteinen eingebaut. Als Bestandteil des aktiven Zentrums dieser Selenoproteine ist Se bzw. SeCys essentiell für deren Funktion. Die Biosynthese der Selenoproteine ist durch eine Reihe von Besonderheiten gekennzeichnet, so z.B. durch eine hierarchisch abgestimmte Versorgung der unterschiedlichen Organ...

  5. Progression of neurodegeneration and morphologic changes in the brains of juvenile mice with selenoprotein P deleted

    OpenAIRE

    Samuel W Caito; Milatovic, Dejan; Hill, Kristina E.; Aschner, Michael; Raymond F Burk; Valentine, William M.

    2011-01-01

    Selenoprotein P (Sepp1) is an important protein involved in selenium (Se) transport and homeostasis. Severe neurologic dysfunction develops in Sepp1 null mice (Sepp1−/−) fed a selenium-deficient diet. Sepp1−/− mice fed a selenium-deficient diet have extensive degeneration of the brainstem and thalamus, and even when supplemented with selenium exhibit subtle learning deficits and altered basal synaptic transmission and short-term plasticity in the CA1 region of the hippocampus. The goal of thi...

  6. Selenoproteins are essential for proper keratinocyte function and skin development.

    Directory of Open Access Journals (Sweden)

    Aniruddha Sengupta

    Full Text Available Dietary selenium is known to protect skin against UV-induced damage and cancer and its topical application improves skin surface parameters in humans, while selenium deficiency compromises protective antioxidant enzymes in skin. Furthermore, skin and hair abnormalities in humans and rodents may be caused by selenium deficiency, which are overcome by dietary selenium supplementation. Most important biological functions of selenium are attributed to selenoproteins, proteins containing selenium in the form of the amino acid, selenocysteine (Sec. Sec insertion into proteins depends on Sec tRNA; thus, knocking out the Sec tRNA gene (Trsp ablates selenoprotein expression. We generated mice with targeted removal of selenoproteins in keratin 14 (K14 expressing cells and their differentiated descendents. The knockout progeny had a runt phenotype, developed skin abnormalities and experienced premature death. Lack of selenoproteins in epidermal cells led to the development of hyperplastic epidermis and aberrant hair follicle morphogenesis, accompanied by progressive alopecia after birth. Further analyses revealed that selenoproteins are essential antioxidants in skin and unveiled their role in keratinocyte growth and viability. This study links severe selenoprotein deficiency to abnormalities in skin and hair and provides genetic evidence for the role of these proteins in keratinocyte function and cutaneous development.

  7. Regulation of Selenocysteine Incorporation into the Selenium Transport Protein, Selenoprotein P*

    Science.gov (United States)

    Shetty, Sumangala P.; Shah, Ravi; Copeland, Paul R.

    2014-01-01

    Selenoproteins are unique as they contain selenium in their active site in the form of the 21st amino acid selenocysteine (Sec), which is encoded by an in-frame UGA stop codon. Sec incorporation requires both cis- and trans-acting factors, which are known to be sufficient for Sec incorporation in vitro, albeit with low efficiency. However, the abundance of the naturally occurring selenoprotein that contains 10 Sec residues (SEPP1) suggests that processive and efficient Sec incorporation occurs in vivo. Here, we set out to study native SEPP1 synthesis in vitro to identify factors that regulate processivity and efficiency. Deletion analysis of the long and conserved 3′-UTR has revealed that the incorporation of multiple Sec residues is inherently processive requiring only the SECIS elements but surprisingly responsive to the selenium concentration. We provide evidence that processive Sec incorporation is linked to selenium utilization and that reconstitution of known Sec incorporation factors in a wheat germ lysate does not permit multiple Sec incorporation events, thus suggesting a role for yet unidentified mammalian-specific processes or factors. The relationship between our findings and the channeling theory of translational efficiency is discussed. PMID:25063811

  8. Relaxation of selective constraints causes independent selenoprotein extinction in insect genomes

    OpenAIRE

    Charles E Chapple; Roderic Guigó

    2008-01-01

    BACKGROUND: Selenoproteins are a diverse family of proteins notable for the presence of the 21st amino acid, selenocysteine. Until very recently, all metazoan genomes investigated encoded selenoproteins, and these proteins had therefore been believed to be essential for animal life. Challenging this assumption, recent comparative analyses of insect genomes have revealed that some insect genomes appear to have lost selenoprotein genes. METHODOLOGY/PRINCIPAL FINDINGS: In this paper we investiga...

  9. Selenoproteins are Essential for Proper Keratinocyte Function and Skin Development

    OpenAIRE

    Sengupta, Aniruddha; Lichti, Ulrike F.; Carlson, Bradley A.; Andrew O Ryscavage; Yuspa, Stuart H.; Hatfield, Dolph L.; Gladyshev, Vadim

    2010-01-01

    Dietary selenium is known to protect skin against UV-induced damage and cancer and its topical application improves skin surface parameters in humans, while selenium deficiency compromises protective antioxidant enzymes in skin. Furthermore, skin and hair abnormalities in humans and rodents may be caused by selenium deficiency, which are overcome by dietary selenium supplementation. Most important biological functions of selenium are attributed to selenoproteins, proteins containing selenium ...

  10. Selenoproteins Are Essential for Proper Keratinocyte Function and Skin Development

    OpenAIRE

    Aniruddha Sengupta; Lichti, Ulrike F.; Carlson, Bradley A.; Ryscavage, Andrew O.; Gladyshev, Vadim N.; Yuspa, Stuart H; Hatfield, Dolph L.

    2010-01-01

    Dietary selenium is known to protect skin against UV-induced damage and cancer and its topical application improves skin surface parameters in humans, while selenium deficiency compromises protective antioxidant enzymes in skin. Furthermore, skin and hair abnormalities in humans and rodents may be caused by selenium deficiency, which are overcome by dietary selenium supplementation. Most important biological functions of selenium are attributed to selenoproteins, proteins containing selenium ...

  11. Selenoproteins reduce susceptibility to DMBA-induced mammary carcinogenesis

    OpenAIRE

    Hudson, Tamaro S.; Carlson, Bradley A.; Hoeneroff, Mark J.; Young, Heather A.; Sordillo, Lorraine; Muller, William J.; Hatfield, Dolph L.; Green, Jeffrey E.

    2012-01-01

    Selenium is an essential micronutrient in the diet of humans and other mammals. Based largely on animal studies and epidemiological evidence, selenium is purported to be a promising cancer chemopreventive agent. However, the biological mechanisms by which chemopreventive activity takes place are poorly understood. It remains unclear whether selenium acts in its elemental form, through incorporation into organic compounds, through selenoproteins or any combination of these. The purpose of this...

  12. Molekulare Regulation der Selenoprotein-Biosynthese und des Selentransports

    OpenAIRE

    Schomburg, Lutz

    2010-01-01

    The essential trace element selenium (Se) has aquired an unparalleled status for biochemistry and physiology since the identification of the 21st proteinogenic amino acid selenocysteine (Sec). The unique physical and chemical properties of Sec are exploited by a small number of selenoproteins which catalyse reactions that are of prime importance for general metabolism, intracellular redox-balance and antioxidative defense. Some of these reactions and some of the responsible selenoenzymes are ...

  13. Reduced serum selenoprotein P concentrations in German prostate cancer patients.

    Science.gov (United States)

    Meyer, Hellmuth-Alexander; Hollenbach, Birgit; Stephan, Carsten; Endermann, Tobias; Morgenthaler, Nils G; Cammann, Henning; Köhrle, Josef; Jung, Klaus; Schomburg, Lutz

    2009-09-01

    Selenium (Se) is essentially needed for the biosynthesis of selenoproteins. Low Se intake causes reduced selenoprotein biosynthesis and constitutes a risk factor for tumorigenesis. Accordingly, some Se supplementation trials have proven effective to reduce prostate cancer risk, especially in poorly supplied individuals. Because Se metabolism is controlled by selenoprotein P (SEPP), we have tested whether circulating SEPP concentrations correlate to prostate cancer stage and grade. A total of 190 men with prostate cancer (n = 90) and "no evidence of malignancy" (NEM; n = 100) histologically confirmed by prostate biopsy were retrospectively analyzed for established tumor markers and for their Se and SEPP status. Prostate specific antigen (PSA), free PSA, total Se, and SEPP concentrations were determined from serum samples and compared with clinicopathologic parameters. The diagnostic performance was analyzed with receiver operating characteristic curves. Median Se and SEPP concentrations differed significantly (P curve (AUC) of a marker combination with age, PSA, and percent free PSA (%fPSA) in combination with the SEPP concentration, yielded the highest diagnostic value (AUC 0.80) compared with the marker combination without SEPP (AUC 0.77) or %fPSA (AUC 0.76). We conclude that decreased SEPP concentration in serum might represent an additional valuable marker for prostate cancer diagnostics. PMID:19690186

  14. Radiation-induced alterations in mitochondrial protein synthesis in rat liver

    International Nuclear Information System (INIS)

    The incorporation of 14C-labeled leucine into hepatic mitochondrial proteins in vivo is enhanced up to 48 hr following whole-body X irradiation. A similar increase in labeling is also observed with liver slices from irradiated rats, incubated in vitro, but not with isolated liver mitochondria. Evidence is presented to indicate that these divergent labeling data may be related to the dual origin of the mitochondrial proteins and differences in the radiation-induced effects on the synthesis of mitochondrial proteins of intra- and extra-mitochondrial origin. The increased labeling observed in vivo does not denote a stimulation of mitochondrial protein synthesis but merely reflects a contraction of the free leucine pool of mitochondria. The possible significance of the radiation-induced alterations in the pattern of mitochondrial protein synthesis to the reported morphological alterations of this organelle is discussed

  15. Selenium and its relationship with selenoprotein P and glutathione peroxidase in children and adolescents with Hashimoto's thyroiditis and hypothyroidism.

    Science.gov (United States)

    Nourbakhsh, Mitra; Ahmadpour, Fatemeh; Chahardoli, Behnam; Malekpour-Dehkordi, Zahra; Nourbakhsh, Mona; Hosseini-Fard, Seyed Reza; Doustimotlagh, Amirhossein; Golestani, Abolfazl; Razzaghy-Azar, Maryam

    2016-03-01

    The essential trace element selenium (Se) is required for thyroid hormone synthesis and metabolism. Selenoproteins contain selenocysteine and are responsible for biological functions of selenium. Glutathione peroxidase (GPx) is one of the major selenoproteins which protects the thyroid cells from oxidative damage. Selenoprotein P (SePP) is considered as the plasma selenium transporter to tissues. The aim of this study was to evaluate serum Se and SePP levels, and GPx activity in erythrocytes of children and adolescents with treated Hashimoto's thyroiditis, hypothyroidism, and normal subjects. Blood samples were collected from 32 patients with Hashimoto's thyroiditis, 20 with hypothyroidism, and 25 matched normal subjects. All the patients were under treatment with levothyroxine and at the time of analysis all of the thyroid function tests were normal. GPx enzyme activity was measured by spectrophotometry at 340 nm. Serum selenium levels were measured by high-resolution continuum source graphite furnace atomic absorption. SePP, TPOAb (anti-thyroid peroxidase antibody), and TgAb (anti-thyroglobulin antibody) were determined by ELISA kits. T4, T3, T3 uptake and TSH were also measured. Neither GPx activity nor SePP levels were significantly different in patients with Hashimoto's thyroiditis or hypothyroidism compared to normal subjects. Although GPx and SePP were both lower in patients with hypothyroidism compared to those with Hashimoto's thyroiditis and normal subjects but the difference was not significant. Serum Se levels also did not differ significantly in patients and normal subjects. We did not find any correlation between GPx or SePP with TPOAb or TgAb but SePP was significantly correlated with Se. Results show that in patients with Hashimoto's thyroiditis or hypothyroidism who have been under treatment with levothyroxine and have normal thyroid function tests, the GPx, SePP and Se levels are not significantly different. PMID:26854239

  16. Decreased hepatotoxic bile acid composition and altered synthesis in progressive human nonalcoholic fatty liver disease

    Energy Technology Data Exchange (ETDEWEB)

    Lake, April D. [University of Arizona, Department of Pharmacology and Toxicology, Tucson, AZ 85721 (United States); Novak, Petr [Biology Centre ASCR, Institute of Plant Molecular Biology, Ceske Budejovice 37001 (Czech Republic); Shipkova, Petia; Aranibar, Nelly; Robertson, Donald; Reily, Michael D. [Pharmaceutical Candidate Optimization, Bristol-Myers Squibb Co., Princeton, NJ 08543 (United States); Lu, Zhenqiang [The Arizona Statistical Consulting Laboratory, University of Arizona, Tucson, AZ 85721 (United States); Lehman-McKeeman, Lois D. [Pharmaceutical Candidate Optimization, Bristol-Myers Squibb Co., Princeton, NJ 08543 (United States); Cherrington, Nathan J., E-mail: cherrington@pharmacy.arizona.edu [University of Arizona, Department of Pharmacology and Toxicology, Tucson, AZ 85721 (United States)

    2013-04-15

    Bile acids (BAs) have many physiological roles and exhibit both toxic and protective influences within the liver. Alterations in the BA profile may be the result of disease induced liver injury. Nonalcoholic fatty liver disease (NAFLD) is a prevalent form of chronic liver disease characterized by the pathophysiological progression from simple steatosis to nonalcoholic steatohepatitis (NASH). The hypothesis of this study is that the ‘classical’ (neutral) and ‘alternative’ (acidic) BA synthesis pathways are altered together with hepatic BA composition during progression of human NAFLD. This study employed the use of transcriptomic and metabolomic assays to study the hepatic toxicologic BA profile in progressive human NAFLD. Individual human liver samples diagnosed as normal, steatosis, and NASH were utilized in the assays. The transcriptomic analysis of 70 BA genes revealed an enrichment of downregulated BA metabolism and transcription factor/receptor genes in livers diagnosed as NASH. Increased mRNA expression of BAAT and CYP7B1 was observed in contrast to decreased CYP8B1 expression in NASH samples. The BA metabolomic profile of NASH livers exhibited an increase in taurine together with elevated levels of conjugated BA species, taurocholic acid (TCA) and taurodeoxycholic acid (TDCA). Conversely, cholic acid (CA) and glycodeoxycholic acid (GDCA) were decreased in NASH liver. These findings reveal a potential shift toward the alternative pathway of BA synthesis during NASH, mediated by increased mRNA and protein expression of CYP7B1. Overall, the transcriptomic changes of BA synthesis pathway enzymes together with altered hepatic BA composition signify an attempt by the liver to reduce hepatotoxicity during disease progression to NASH. - Highlights: ► Altered hepatic bile acid composition is observed in progressive NAFLD. ► Bile acid synthesis enzymes are transcriptionally altered in NASH livers. ► Increased levels of taurine and conjugated bile acids

  17. Decreased hepatotoxic bile acid composition and altered synthesis in progressive human nonalcoholic fatty liver disease

    International Nuclear Information System (INIS)

    Bile acids (BAs) have many physiological roles and exhibit both toxic and protective influences within the liver. Alterations in the BA profile may be the result of disease induced liver injury. Nonalcoholic fatty liver disease (NAFLD) is a prevalent form of chronic liver disease characterized by the pathophysiological progression from simple steatosis to nonalcoholic steatohepatitis (NASH). The hypothesis of this study is that the ‘classical’ (neutral) and ‘alternative’ (acidic) BA synthesis pathways are altered together with hepatic BA composition during progression of human NAFLD. This study employed the use of transcriptomic and metabolomic assays to study the hepatic toxicologic BA profile in progressive human NAFLD. Individual human liver samples diagnosed as normal, steatosis, and NASH were utilized in the assays. The transcriptomic analysis of 70 BA genes revealed an enrichment of downregulated BA metabolism and transcription factor/receptor genes in livers diagnosed as NASH. Increased mRNA expression of BAAT and CYP7B1 was observed in contrast to decreased CYP8B1 expression in NASH samples. The BA metabolomic profile of NASH livers exhibited an increase in taurine together with elevated levels of conjugated BA species, taurocholic acid (TCA) and taurodeoxycholic acid (TDCA). Conversely, cholic acid (CA) and glycodeoxycholic acid (GDCA) were decreased in NASH liver. These findings reveal a potential shift toward the alternative pathway of BA synthesis during NASH, mediated by increased mRNA and protein expression of CYP7B1. Overall, the transcriptomic changes of BA synthesis pathway enzymes together with altered hepatic BA composition signify an attempt by the liver to reduce hepatotoxicity during disease progression to NASH. - Highlights: ► Altered hepatic bile acid composition is observed in progressive NAFLD. ► Bile acid synthesis enzymes are transcriptionally altered in NASH livers. ► Increased levels of taurine and conjugated bile acids

  18. New selenoproteins identified in silico from the genome of Anopheles gambiae

    Institute of Scientific and Technical Information of China (English)

    JIANG Liang; LIU Qiong; CHEN Ping; GAO ZhongHong; XU HuiBi

    2007-01-01

    Selenoprotein is biosynthesized by the incorporation of selenocysteine into proteins, where the TGA codon in the open reading frame does not act as a stop signal but is translated into selenocysteine. The dual functions of TGA result in mis-annotation or lack of selenoproteins in the sequenced genomes of many species. Available computational tools fail to correctly predict selenoproteins. Thus, we developed a new method to identify selenoproteins from the genome of Anopheles gambiae computationally.Based on released genomic information, several programs were edited with PERL language to identify selenocysteine insertion sequence (SECIS) element, the coding potential of TGA codons, and cysteine-containing homologs of selenoprotein genes. Our results showed that 11365 genes were terminated with TGA codons, 918 of which contained SECIS elements. Similarity search revealed that 58genes contained Sec/Cys pairs and similar flanking regions around in-frame TGA codons. Finally, 7genes were found to fully meet requirements for selenoproteins, although they have not been annotated as selenoproteins in NCBI databases. Deduced from their basic properties, the newly found selenoproteins in the genome of Anopheles gambiae are possibly related to in vivo oxidation tolerance and protein regulation in order to interfere with anopheles' vectorial capacity of Plasmodium. This study may also provide theoretical bases for the prevention of malaria from anopheles transmission.

  19. Selenoprotein N: an endoplasmic reticulum glycoprotein with an early developmental expression pattern

    DEFF Research Database (Denmark)

    Petit, Nathalie; Lescure, Alain; Rederstorff, Mathieu;

    2003-01-01

    Rigid spine muscular dystrophy and the classical form of multiminicore disease are caused by mutations in SEPN1 gene, leading to a new clinical entity referred to as SEPN1-related myopathy. SEPN1 codes for selenoprotein N, a new member of the selenoprotein family, the function of which is still...

  20. Secisbp2 Is Essential for Embryonic Development and Enhances Selenoprotein Expression

    Science.gov (United States)

    Seeher, Sandra; Atassi, Tarik; Mahdi, Yassin; Carlson, Bradley A.; Braun, Doreen; Wirth, Eva K.; Klein, Marc O.; Reix, Nathalie; Miniard, Angela C.; Schomburg, Lutz; Hatfield, Dolph L.; Driscoll, Donna M.

    2014-01-01

    Abstract Aims: The selenocysteine insertion sequence (SECIS)-binding protein 2 (Secisbp2) binds to SECIS elements located in the 3′-untranslated region of eukaryotic selenoprotein mRNAs. Selenoproteins contain the rare amino acid selenocysteine (Sec). Mutations in SECISBP2 in humans lead to reduced selenoprotein expression thereby affecting thyroid hormone-dependent growth and differentiation processes. The most severe cases also display myopathy, hearing impairment, male infertility, increased photosensitivity, mental retardation, and ataxia. Mouse models are needed to understand selenoprotein-dependent processes underlying the patients' pleiotropic phenotypes. Results: Unlike tRNA[Ser]Sec-deficient embryos, homozygous Secisbp2-deleted embryos implant, but fail before gastrulation. Heterozygous inactivation of Secisbp2 reduced the amount of selenoprotein expressed, but did not affect the thyroid hormone axis or growth. Conditional deletion of Secisbp2 in hepatocytes significantly decreased selenoprotein expression. Unexpectedly, the loss of Secisbp2 reduced the abundance of many, but not all, selenoprotein mRNAs. Transcript-specific and gender-selective effects on selenoprotein mRNA abundance were greater in Secisbp2-deficient hepatocytes than in tRNA[Ser]Sec-deficient cells. Despite the massive reduction of Dio1 and Sepp1 mRNAs, significantly more corresponding protein was detected in primary hepatocytes lacking Secisbp2 than in cells lacking tRNA[Ser]Sec. Regarding selenoprotein expression, compensatory nuclear factor, erythroid-derived, like 2 (Nrf2)-dependent gene expression, or embryonic development, phenotypes were always milder in Secisbp2-deficient than in tRNA[Ser]Sec-deficient mice. Innovation: We report the first Secisbp2 mutant mouse models. The conditional mutants provide a model for analyzing Secisbp2 function in organs not accessible in patients. Conclusion: In hepatocyte-specific conditional mouse models, Secisbp2 gene inactivation is less

  1. Untersuchungen zur Expression und Verteilung von Selenoprotein P

    OpenAIRE

    Scharpf, Marcus

    2012-01-01

    We studied the distribution of Selenoprotein P (SePP) on mRNA and protein level. Using in-situ hybridisation on selected murine tissues, we showed tissue- and cell specific SePP-mRNA distribution. These results were confirmed and correlated using a commercially available human mRNA expression array. In an effort to study SePP protein localization, we established immunohistochemical stainings using three different antibodies directed against human SePP. Distribution of SePP in the Human brain ...

  2. Selenium Deficiency Mainly Influences Antioxidant Selenoproteins Expression in Broiler Immune Organs.

    Science.gov (United States)

    Yang, Zijiang; Liu, Ci; Liu, Chunpeng; Teng, Xiaohua; Li, Shu

    2016-07-01

    Selenoprotein has many functions in chicken, and the expression of selenoproteins is closely associated with the selenium (Se) level. However, little is known about the expression patterns of selenoproteins in chicken immune organs. Here, we investigated the effect of dietary Se deficiency on the expressions of 23 selenoproteins in broiler immune organs. In this study, 150 broilers were randomly divided into two groups (75 chickens per group). The chickens were maintained either on a diet supplemented with Se through the addition of 0.2 mg/kg of Se (C group) via sodium selenite or on a Se-deficient granulated diet (L group) until the broilers exhibited an onset of exudative diathesis (ED). Following euthanasia, the samples from the immune tissues (including the spleen, thymus, and bursa of Fabricius) were quickly collected, and the messenger RNA (mRNA) expression levels of 23 selenoproteins were examined by real-time quantitative PCR and analyzed using principal component analysis. The results showed that Se deficiency decreased the mRNA levels of 23 selenoproteins in the thymus, spleen, and bursa of the Fabricius tissues of broiler chickens. Furthermore, we found that among 23 selenoproteins, the mRNA levels of Dio1 in the thymus, Txnrd2 in the spleen, and Txnrd3 in the bursa of Fabricius decreased significantly (90.9 %, 83.3 %, and 96.8 %, respectively). In addition, the principal component analysis (PCA) results suggested that Se deficiency mainly influenced the expression of antioxidative selenoproteins, especially glutathione peroxidases (Gpxs), thioredoxin reductases (Txnrds), and iodothyronine deiodinases (Dios) in chicken immune organs. The results of this study are valuable for understanding the relevance of selenoprotein activity in vivo. PMID:26631053

  3. Serum selenium and selenoprotein P status in adult Danes-8-year followup

    DEFF Research Database (Denmark)

    Rasmussen, Lone Banke; Hollenbach, B.; Laurberg, P.; Carlé, A.; Hög, A.; Jørgensen, T.; Vejbjerg, P.; Ovesen, L.; Schomburg, L.

    2009-01-01

    subjects had filled in a food frequency questionnaire (FFQ) and a questionnaire with information about smoking habits, alcohol consumption and exercise habits. Mean serum selenium level was 98.7+/-19.8microg/L and median selenoprotein P level was 2.72 (2.18-3.49)mg/L. Serum selenium and selenoprotein P...... selenoprotein P level. Smoking status, alcohol intake, exercise habits, BMI and medicine use did not influence selenium status. It is concluded that selenium status in this Danish population is at an acceptable level. No major groups with regard to age, sex or lifestyle factors could be identified as being in...

  4. The protozoa dinoflagellate Oxyrrhis marina contains selenoproteins and the relevant translation apparatus

    International Nuclear Information System (INIS)

    In the phylogenetic tree, selenoproteins and the corresponding translation machinery are found in Archaea, Eubacteria, and animals, but not in fungi and higher plants. As very little is known about Protozoa, we searched for the presence of selenoproteins in the primitive dinoflagellate Oxyrrhis marina, belonging to the Protoctista kingdom. Four selenoproteins could be obtained from O. marina cells cultured in the presence of 75Se. Using O. marina or bovine liver cytosolic extracts, we could serylate and selenylate in vitro total O. marina tRNAs. Moreover, the existence of a tRNASec could be deduced from in vivo experiments. Lastly, an anti-serum against the specialized mammalian translation elongation factor mSelB reacted with a protein of 48-kDa molecular mass. Altogether, our data showed that O. marina contains selenoproteins and suggests that the corresponding translation machinery is related to that found in animals

  5. Identification of selenocyst- eine insertion sequence (SECIS) element in eukaryotic selenoproteins by RNA Draw program

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The computer program RNA Draw was used to identify the secondary structures in the 3′ untranslated re- gions (3′UTRs) of the mRNAs from 46 eukaryotic seleno- proteins among 7 species. The program found one or two possible SECIS elements in these selenoproteins. The SECIS element consists of a stem-loop or hairpin structure with three conserved sequences of AUGA-(A)AA-GA. SECIS element was not found by the RNA Draw program in randomly selected non-selenoproteins. The results showed that SECIS element is the unique character of the genes of eukaryotic selenoproteins. Thus it is possible to use RNA Draw to search the SECIS elements in gene bank for poten- tial new selenoproteins.

  6. Burn injury differentially alters whole-blood and organ glutathione synthesis rates: An experimental model

    Directory of Open Access Journals (Sweden)

    Zhe-Wei Fei

    2013-09-01

    Full Text Available Previous studies from our laboratories revealed a reduced rate of whole-blood (WB glutathione (GSH synthesis in severely burned patients. To determine whether WB GSH metabolism is an indicator of the status of GSH metabolism in one or more of the major organs, we used a burn rabbit model to determine GSH concentrations and rates of synthesis in WB, liver, lungs, kidney, and skeletal muscle. L-[1- 13 C]-cysteine was infused intravenously for 6 h in rabbits at 3 days post-burn and in sham burn controls. WB and organ 13 C-enrichment of cysteine and GSH was determined by gas chromatography/mass spectrometry. Plasma cysteine metabolic flux was increased significantly (P < 0.01 following burn injury. WB, liver, and lung GSH concentrations (P = 0.054, P < 0.05, and P < 0.05, respectively and fractional rates of GSH synthesis (P < 0.05, P< 0.01, and P< 0.05, respectively were reduced at 3 days post-burn. Kidney was unaffected. There also appears to be an increased rate of GSH transport out of the liver after burn injury. Hence, there is a differential impact of burn injury on tissue and organ GSH status, with WB qualitatively reflecting the changes in lung and liver. It will be important to determine whether these changes are due to alterations in the intrinsic capacity for GSH synthesis and/or availability of amino acid precursors of GSH.

  7. Selenoprotein P influences colitis-induced tumorigenesis by mediating stemness and oxidative damage

    OpenAIRE

    Caitlyn W Barrett; Reddy, Vishruth K.; Short, Sarah P.; Motley, Amy K.; Lintel, Mary K.; Bradley, Amber M.; Freeman, Tanner; Vallance, Jefferson; Ning, Wei; Parang, Bobak; Poindexter, Shenika V.; Fingleton, Barbara; Chen, Xi; Washington, Mary K.; Wilson, Keith T.

    2015-01-01

    Patients with inflammatory bowel disease are at increased risk for colon cancer due to augmented oxidative stress. These patients also have compromised antioxidant defenses as the result of nutritional deficiencies. The micronutrient selenium is essential for selenoprotein production and is transported from the liver to target tissues via selenoprotein P (SEPP1). Target tissues also produce SEPP1, which is thought to possess an endogenous antioxidant function. Here, we have shown that mice wi...

  8. Effects of Selenium Supplementation on Selenoprotein Gene Expression and Response to Influenza Vaccine Challenge: A Randomised Controlled Trial

    OpenAIRE

    Goldson, Andrew J.; Fairweather-Tait, Susan J; Armah, Charlotte N.; Bao, Yongping; Broadley, Martin R.; Dainty, Jack R.; Furniss, Caroline; Hart, David J.; Teucher, Birgit; Hurst, Rachel

    2011-01-01

    Background The uncertainty surrounding dietary requirements for selenium (Se) is partly due to limitations in biomarkers of Se status that are related to health outcomes. In this study we determined the effect of different doses and forms of Se on gene expression of selenoprotein S (SEPS1), selenoprotein W (SEPW1) and selenoprotein R (SEPR), and responses to an immune function challenge, influenza vaccine, were measured in order to identify functional markers of Se status. Methods and Finding...

  9. Genetic variation in selenoprotein genes, lifestyle, and risk of colon and rectal cancer.

    Directory of Open Access Journals (Sweden)

    Martha L Slattery

    Full Text Available BACKGROUND: Associations between selenium and cancer have directed attention to role of selenoproteins in the carcinogenic process. METHODS: We used data from two population-based case-control studies of colon (n = 1555 cases, 1956 controls and rectal (n = 754 cases, 959 controls cancer. We evaluated the association between genetic variation in TXNRD1, TXNRD2, TXNRD3, C11orf31 (SelH, SelW, SelN1, SelS, SepX, and SeP15 with colorectal cancer risk. RESULTS: After adjustment for multiple comparisons, several associations were observed. Two SNPs in TXNRD3 were associated with rectal cancer (rs11718498 dominant OR 1.42 95% CI 1.16,1.74 pACT 0.0036 and rs9637365 recessive 0.70 95% CI 0.55,0.90 pACT 0.0208. Four SNPs in SepN1 were associated with rectal cancer (rs11247735 recessive OR 1.30 95% CI 1.04,1.63 pACT 0.0410; rs2072749 GGvsAA OR 0.53 95% CI 0.36,0.80 pACT 0.0159; rs4659382 recessive OR 0.58 95% CI 0.39,0.86 pACT 0.0247; rs718391 dominant OR 0.76 95% CI 0.62,0.94 pACT 0.0300. Interaction between these genes and exposures that could influence these genes showed numerous significant associations after adjustment for multiple comparisons. Two SNPs in TXNRD1 and four SNPs in TXNRD2 interacted with aspirin/NSAID to influence colon cancer; one SNP in TXNRD1, two SNPs in TXNRD2, and one SNP in TXNRD3 interacted with aspirin/NSAIDs to influence rectal cancer. Five SNPs in TXNRD2 and one in SelS, SeP15, and SelW1 interacted with estrogen to modify colon cancer risk; one SNP in SelW1 interacted with estrogen to alter rectal cancer risk. Several SNPs in this candidate pathway influenced survival after diagnosis with colon cancer (SeP15 and SepX1 increased HRR and rectal cancer (SepX1 increased HRR. CONCLUSIONS: Findings support an association between selenoprotein genes and colon and rectal cancer development and survival after diagnosis. Given the interactions observed, it is likely that the impact of cancer susceptibility from genotype is

  10. Selenium Deficiency Influences the mRNA Expression of Selenoproteins and Cytokines in Chicken Erythrocytes.

    Science.gov (United States)

    Luan, Yilin; Zhao, Jinxin; Yao, Haidong; Zhao, Xia; Fan, Ruifeng; Zhao, Wenchao; Zhang, Ziwei; Xu, Shiwen

    2016-06-01

    Selenium (Se) deficiency induces hemolysis in chickens, but the molecular mechanism for this effect remains unclear. Se primarily elicits its function through the activity of selenoproteins, which contain the unique amino acid selenocysteine (Sec). In this study, we aimed to investigate the effect of Se deficiency on the expression of 24 selenoproteins and 10 cytokines. One hundred eighty chickens were randomly divided into 2 groups (90 chickens per group). During the entire experimental period, chickens were allowed ad libitum consumption of feed and water. The chickens were fed either a Se-deficient diet (0.008 mg Se/kg; produced in the Se-deficient area of Heilongjiang, China) or a Se-supplemented diet (as sodium selenite) at 0.2 mg/kg for 35 days. At the 35th day, the messenger RNA (mRNA) levels of 24 selenoproteins and 10 cytokines were examined in erythrocytes of 5 chickens per group, and the correlation was analyzed. The results showed that the expression of 24 selenoproteins and 7 cytokines (IL-2, IL-4, IL-8, IL-10, IL-12β, TGF-β4, and IFN-γ) decreased (P < 0.05), and the expression of 3 cytokines (IL-1γ, IL-6 and IL-7) was higher in the Se-deficient group. In both groups, glutathione peroxidase (GPX), thioredoxin 1 (Txnrd1), selenoprotein P1 (SELP), and selenoprotein synthetase (SPS2) were highly expressed compared to the other selenoproteins in chicken erythrocytes (P < 0.05). These data suggest that GPXs, Txnrd1, SELP, and SPS2 possibly play a more important role than the other selenoproteins. The increase of pro-inflammatory cytokines (IL-1γ, IL-6, and IL-7) suggested that the immune system of chickens was damaged by the Se deficiency. Correlation analysis suggested that although the expression of 24 selenoproteins and 7 cytokines decreased and that of 3 cytokines increased, there was a close correlation between their expression levels and a Se diet. These results suggested that Se deficiency influenced the expressions of 24 selenoproteins

  11. Factors impacting the aminoglycoside-induced UGA stop codon readthrough in selenoprotein translation.

    Science.gov (United States)

    Martitz, Janine; Hofmann, Peter Josef; Johannes, Jörg; Köhrle, Josef; Schomburg, Lutz; Renko, Kostja

    2016-09-01

    Aminoglycosides (AG) are oligosaccharide antibiotics that interfere with the small ribosomal subunit in aerobic, Gram-negative bacteria, causing pathogen-destructing error rates in their protein biosynthesis. Aminoglycosides also induce mRNA misinterpretation in eukaryotic cells, especially of the UGA (Opal)-stop codon, albeit to a lower extent. UGA recoding is essentially required for the incorporation of selenocysteine (Sec) into growing selenoproteins during translation. Selenocysteine incorporation requires the presence of a selenoprotein-specific stem-loop structure within the 3'-untranslated region of the mRNA, the so-called Sec-insertion sequence (SECIS) element. Interestingly, selenoprotein genes differ in their SECIS-element sequence and in their UGA base context. We hypothesized that the SECIS-element and the specific codon context synergize in controlling the effects of AG on stop codon readthrough. To this end, the SECIS-elements of glutathione peroxidase 1, glutathione peroxidase 4 and selenoprotein P transcripts were cloned into a reporter system and analyzed in combination with different UGA codon contexts. Our results indicate that a cytosine in position 4 (directly downstream of UGA) confers strongest effects on both the Se- and AG-dependent readthrough. Overall selenoprotein biosynthesis rate depends on the Se-status, AG concentration and the specific SECIS-element present in the transcript. These findings help to get a better understanding for the susceptibility of different transcripts towards AG-mediated interference with the biosynthesis of functional Se-containing selenoproteins, and highlight the importance of the Se-status for successful selenoprotein biosynthesis under antibiotic therapy. PMID:27157664

  12. Impaired selenoprotein expression in brain triggers striatal neuronal loss leading to coordination defects in mice

    Science.gov (United States)

    Seeher, Sandra; Carlson, Bradley A.; Miniard, Angela C.; Wirth, Eva K.; Mahdi, Yassin; Hatfield, Dolph L.; Driscoll, Donna M.; Schweizer, Ulrich

    2014-01-01

    Selenocysteine Insertion Sequence (SECIS)-Binding Protein 2 (Secisbp2) binds to SECIS elements located in the 3′-untranslated region of eukaryotic selenoprotein mRNAs. It facilitates incorporation of the rare amino acid selenocysteine in response to UGA codons. Inactivation of Secisbp2 in hepatocytes greatly reduced selenoprotein levels. Neuron-specific inactivation of Secisbp2 (CamK-Cre; Secisbp2fl/fl) reduced cerebral expression of selenoproteins to a lesser extent than inactivation of tRNA[Ser]Sec. This allowed us to study the development of cortical parvalbumin-positive (PV+) interneurons, which are completely lost in tRNA[Ser]Sec mutants. PV+ interneuron density was reduced in the somatosensory cortex, hippocampus, and striatum. In situ-hybridization for Gad67 confirmed the reduction of GABAergic interneurons. Because of the obvious movement phenotype involving a broad, dystonic gait, we suspected basal ganglia dysfunction. Tyrosine hydroxylase expression was normal in substantia nigra neurons and their striatal terminals. However the densities of striatal PV+ and Gad67+ neurons were decreased by 65% and 49%, respectively. Likewise, the density of striatal cholinergic neurons was reduced by 68%. Our observations demonstrate that several classes of striatal interneurons depend on selenoprotein expression. These findings may offer an explanation for the movement phenotype of selenoprotein P-deficient mice and the movement disorder and mental retardation described in a patient carrying SECISBP2 mutations. PMID:24844465

  13. Altered Lipid Synthesis by Lack of Yeast Pah1 Phosphatidate Phosphatase Reduces Chronological Life Span.

    Science.gov (United States)

    Park, Yeonhee; Han, Gil-Soo; Mileykovskaya, Eugenia; Garrett, Teresa A; Carman, George M

    2015-10-16

    In Saccharomyces cerevisiae, Pah1 phosphatidate phosphatase, which catalyzes the dephosphorylation of phosphatidate to yield diacylglycerol, plays a crucial role in the synthesis of the storage lipid triacylglycerol. This evolutionarily conserved enzyme also plays a negative regulatory role in controlling de novo membrane phospholipid synthesis through its consumption of phosphatidate. We found that the pah1Δ mutant was defective in the utilization of non-fermentable carbon sources but not in oxidative phosphorylation; the mutant did not exhibit major changes in oxygen consumption rate, mitochondrial membrane potential, F1F0-ATP synthase activity, or gross mitochondrial morphology. The pah1Δ mutant contained an almost normal complement of major mitochondrial phospholipids with some alterations in molecular species. Although oxidative phosphorylation was not compromised in the pah1Δ mutant, the cellular levels of ATP in quiescent cells were reduced by 2-fold, inversely correlating with a 4-fold increase in membrane phospholipids. In addition, the quiescent pah1Δ mutant cells had 3-fold higher levels of mitochondrial superoxide and cellular lipid hydroperoxides, had reduced activities of superoxide dismutase 2 and catalase, and were hypersensitive to hydrogen peroxide. Consequently, the pah1Δ mutant had a shortened chronological life span. In addition, the loss of Tsa1 thioredoxin peroxidase caused a synthetic growth defect with the pah1Δ mutation. The shortened chronological life span of the pah1Δ mutant along with its growth defect on non-fermentable carbon sources and hypersensitivity to hydrogen peroxide was suppressed by the loss of Dgk1 diacylglycerol kinase, indicating that the underpinning of pah1Δ mutant defects was the excess synthesis of membrane phospholipids. PMID:26338708

  14. Cloning, Sequencing, and Expression of Selenoprotein Transcripts in the Turkey (Meleagris gallopavo.

    Directory of Open Access Journals (Sweden)

    Roger A Sunde

    Full Text Available The minimum Se requirement for male turkey poults is 0.3 μg Se/g--three times higher than requirements found in rodents--based on liver and gizzard glutathione peroxidase-4 (GPX4 and GPX1 activities. In addition, turkey liver GPX4 activity is 10-fold higher and GPX1 activity is 10-fold lower than in rats, and both GPX1 and GPX4 mRNA levels are dramatically down-regulated by Se deficiency. Currently, the sequences of all annotated turkey selenoprotein transcripts and proteins in the NCBI database are only "predicted." Thus we initiated cloning and sequencing of the full turkey selenoprotein transcriptome to demonstrate expression of selenoprotein transcripts in the turkey, and to develop tools to investigate Se regulation of the full selenoproteome. Total RNA was isolated from six tissues of Se-adequate adult tom turkeys, and used to prepare reverse-transcription cDNA libraries. PCR primers were designed, based initially on chicken, rodent, porcine, bovine and human sequences and later on turkey shotgun cloning sequences. We report here the cloning of full transcript sequences for 9 selenoproteins, and 3'UTR portions for 15 additional selenoproteins, which include SECIS elements in 22 3'UTRs, and in-frame Sec (UGA codons within coding regions of 19 selenoproteins, including 12 Sec codons in SEPP1. In addition, we sequenced the gap between two contigs from the shotgun cloning of the turkey genome, and found the missing sequence for the turkey Sec-tRNA. RTPCR was used to determine the relative transcript expression in 6 tissues. GPX3 expression was high in all tissues except kidney, GPX1 expression was high in kidney, SEPW1 expression was high in heart, gizzard and muscle, and SELU expression was high in liver. SEPP2, a selenoprotein not found in mammals, was highly expressed in liver but not in other tissues. In summary, transcripts for 24 selenoproteins are expressed in the turkey, not just predicted.

  15. Deletion of Selenoprotein P Upregulates Urinary Selenium Excretion and Depresses Whole-body Selenium Content

    OpenAIRE

    Raymond F Burk; Hill, Kristina E.; Motley, Amy K.; Austin, Lori M.; Norsworthy, Brooke K.

    2006-01-01

    Deletion of the mouse selenoprotein P gene (Sepp1) lowers selenium concentrations in many tissues. We examined selenium homeostasis in Sepp1−/− and Sepp1+/+ mice to assess the mechanism of this. The liver produces and exports selenoprotein P, which transports selenium to peripheral tissues, and urinary selenium metabolites, which regulate whole-body selenium. At intakes of selenium near the nutritional requirement, Sepp1−/− mice had whole-body selenium concentrations 72 to 75% of Sepp1+/+ mic...

  16. Aquatic contaminants alter genes involved in neurotransmitter synthesis and gonadotropin release in largemouth bass

    International Nuclear Information System (INIS)

    Many aquatic contaminants potentially affect the central nervous system, however the underlying mechanisms of how toxicants alter normal brain function are not well understood. The objectives of this study were to compare the effects of emerging and prevalent environmental contaminants on the expression of brain transcripts with a role in neurotransmitter synthesis and reproduction. Adult male largemouth bass (Micropterus salmoides) were injected once for a 96 h duration with control (water or oil) or with one of two doses of a single chemical to achieve the following body burdens (μg/g): atrazine (0.3 and 3.0), toxaphene (10 and 100), cadmium (CdCl2) (0.000067 and 0.00067), polychlorinated biphenyl (PCB) 126 (0.25 and 2.5), and phenanthrene (5 and 50). Partial largemouth bass gene segments were cloned for enzymes involved in neurotransmitter (glutamic acid decarboxylase 65, GAD65; tyrosine hydroxylase) and estrogen (brain aromatase; CYP19b) synthesis for real-time PCR assays. In addition, neuropeptides regulating feeding (neuropeptide Y) and reproduction (chicken GnRH-II, cGnRH-II; salmon GnRH, sGnRH) were also investigated. Of the chemicals tested, only cadmium, PCB 126, and phenanthrene showed any significant effects on the genes tested, while atrazine and toxaphene did not. Cadmium (0.000067 μg/g) significantly increased cGnRH-II mRNA while PCB 126 (0.25 μg/g) decreased GAD65 mRNA. Phenanthrene decreased GAD65 and tyrosine hydroxylase mRNA levels at the highest dose (50 μg/g) but increased cGnRH-II mRNA at the lowest dose (5 μg/g). CYP19b, NPY, and sGnRH mRNA levels were unaffected by any of the treatments. A hierarchical clustering dendrogram grouped PCB 126 and phenanthrene more closely than other chemicals with respect to the genes tested. This study demonstrates that brain transcripts important for neurotransmitter synthesis neuroendocrine function are potential targets for emerging and prevalent aquatic contaminants.

  17. Aquatic contaminants alter genes involved in neurotransmitter synthesis and gonadotropin release in largemouth bass

    Energy Technology Data Exchange (ETDEWEB)

    Martyniuk, Christopher J. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Sanchez, Brian C. [Department of Forestry and Natural Resources and School of Civil Engineering, 195 Marsteller St., Purdue University, West Lafayette, IN 47907 (United States); Szabo, Nancy J.; Denslow, Nancy D. [Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Sepulveda, Maria S., E-mail: mssepulv@purdue.edu [Department of Forestry and Natural Resources and School of Civil Engineering, 195 Marsteller St., Purdue University, West Lafayette, IN 47907 (United States)

    2009-10-19

    Many aquatic contaminants potentially affect the central nervous system, however the underlying mechanisms of how toxicants alter normal brain function are not well understood. The objectives of this study were to compare the effects of emerging and prevalent environmental contaminants on the expression of brain transcripts with a role in neurotransmitter synthesis and reproduction. Adult male largemouth bass (Micropterus salmoides) were injected once for a 96 h duration with control (water or oil) or with one of two doses of a single chemical to achieve the following body burdens ({mu}g/g): atrazine (0.3 and 3.0), toxaphene (10 and 100), cadmium (CdCl{sub 2}) (0.000067 and 0.00067), polychlorinated biphenyl (PCB) 126 (0.25 and 2.5), and phenanthrene (5 and 50). Partial largemouth bass gene segments were cloned for enzymes involved in neurotransmitter (glutamic acid decarboxylase 65, GAD65; tyrosine hydroxylase) and estrogen (brain aromatase; CYP19b) synthesis for real-time PCR assays. In addition, neuropeptides regulating feeding (neuropeptide Y) and reproduction (chicken GnRH-II, cGnRH-II; salmon GnRH, sGnRH) were also investigated. Of the chemicals tested, only cadmium, PCB 126, and phenanthrene showed any significant effects on the genes tested, while atrazine and toxaphene did not. Cadmium (0.000067 {mu}g/g) significantly increased cGnRH-II mRNA while PCB 126 (0.25 {mu}g/g) decreased GAD65 mRNA. Phenanthrene decreased GAD65 and tyrosine hydroxylase mRNA levels at the highest dose (50 {mu}g/g) but increased cGnRH-II mRNA at the lowest dose (5 {mu}g/g). CYP19b, NPY, and sGnRH mRNA levels were unaffected by any of the treatments. A hierarchical clustering dendrogram grouped PCB 126 and phenanthrene more closely than other chemicals with respect to the genes tested. This study demonstrates that brain transcripts important for neurotransmitter synthesis neuroendocrine function are potential targets for emerging and prevalent aquatic contaminants.

  18. Aquatic contaminants alter genes involved in neurotransmitter synthesis and gonadotropin release in largemouth bass.

    Science.gov (United States)

    Martyniuk, Christopher J; Sanchez, Brian C; Szabo, Nancy J; Denslow, Nancy D; Sepúlveda, Maria S

    2009-10-19

    Many aquatic contaminants potentially affect the central nervous system, however the underlying mechanisms of how toxicants alter normal brain function are not well understood. The objectives of this study were to compare the effects of emerging and prevalent environmental contaminants on the expression of brain transcripts with a role in neurotransmitter synthesis and reproduction. Adult male largemouth bass (Micropterus salmoides) were injected once for a 96 h duration with control (water or oil) or with one of two doses of a single chemical to achieve the following body burdens (microg/g): atrazine (0.3 and 3.0), toxaphene (10 and 100), cadmium (CdCl(2)) (0.000067 and 0.00067), polychlorinated biphenyl (PCB) 126 (0.25 and 2.5), and phenanthrene (5 and 50). Partial largemouth bass gene segments were cloned for enzymes involved in neurotransmitter (glutamic acid decarboxylase 65, GAD65; tyrosine hydroxylase) and estrogen (brain aromatase; CYP19b) synthesis for real-time PCR assays. In addition, neuropeptides regulating feeding (neuropeptide Y) and reproduction (chicken GnRH-II, cGnRH-II; salmon GnRH, sGnRH) were also investigated. Of the chemicals tested, only cadmium, PCB 126, and phenanthrene showed any significant effects on the genes tested, while atrazine and toxaphene did not. Cadmium (0.000067 microg/g) significantly increased cGnRH-II mRNA while PCB 126 (0.25 microg/g) decreased GAD65 mRNA. Phenanthrene decreased GAD65 and tyrosine hydroxylase mRNA levels at the highest dose (50 microg/g) but increased cGnRH-II mRNA at the lowest dose (5 microg/g). CYP19b, NPY, and sGnRH mRNA levels were unaffected by any of the treatments. A hierarchical clustering dendrogram grouped PCB 126 and phenanthrene more closely than other chemicals with respect to the genes tested. This study demonstrates that brain transcripts important for neurotransmitter synthesis neuroendocrine function are potential targets for emerging and prevalent aquatic contaminants. PMID:19781795

  19. Selenoprotein S expression in reactive astrocytes following brain injury.

    Science.gov (United States)

    Fradejas, Noelia; Serrano-Pérez, Maria Del Carmen; Tranque, Pedro; Calvo, Soledad

    2011-06-01

    Selenoprotein S (SelS) is an endoplasmic reticulum (ER)-resident protein involved in the unfolded protein response. Besides reducing ER-stress, SelS attenuates inflammation by decreasing pro-inflammatory cytokines. We have recently shown that SelS is responsive to ischemia in cultured astrocytes. To check the possible association of SelS with astrocyte activation, here we investigate the expression of SelS in two models of brain injury: kainic acid (KA) induced excitotoxicity and cortical mechanical lesion. The regulation of SelS and its functional consequences for neuroinflammation, ER-stress, and cell survival were further analyzed using cultured astrocytes from mouse and human. According to our immunofluorescence analysis, SelS expression is prominent in neurons and hardly detectable in astrocytes from control mice. However, brain injury intensely upregulates SelS, specifically in reactive astrocytes. SelS induction by KA was evident at 12 h and faded out after reaching maximum levels at 3-4 days. Analysis of mRNA and protein expression in cultured astrocytes showed SelS upregulation by inflammatory stimuli as well as ER-stress inducers. In turn, siRNA-mediated SelS silencing combined with adenoviral overexpression assays demonstrated that SelS reduces ER-stress markers CHOP and spliced XBP-1, as well as inflammatory cytokines IL-1β and IL-6 in stimulated astrocytes. SelS overexpression increased astrocyte resistance to ER-stress and inflammatory stimuli. Conversely, SelS suppression compromised astrocyte viability. In summary, our results reveal the upregulation of SelS expression in reactive astrocytes, as well as a new protective role for SelS against inflammation and ER-stress that can be relevant to astrocyte function in the context of inflammatory neuropathologies. PMID:21456042

  20. Selenoprotein W controls epidermal growth factor receptor surface expression, activation and degradation via receptor ubiquitination

    Science.gov (United States)

    Epidermal growth factor (EGF) receptor (EGFR) is the founding member of the ErbB family of growth factor receptors that modulate a complex network of intracellular signaling pathways controlling growth, proliferation and differentiation. Selenoprotein W (SEPW1) is a diet-regulated, highly conserved...

  1. Selenoprotein N deficiency in mice is associated with abnormal lung development.

    Science.gov (United States)

    Moghadaszadeh, Behzad; Rider, Branden E; Lawlor, Michael W; Childers, Martin K; Grange, Robert W; Gupta, Kushagra; Boukedes, Steve S; Owen, Caroline A; Beggs, Alan H

    2013-04-01

    Mutations in the human SEPN1 gene, encoding selenoprotein N (SepN), cause SEPN1-related myopathy (SEPN1-RM) characterized by muscle weakness, spinal rigidity, and respiratory insufficiency. As with other members of the selenoprotein family, selenoprotein N incorporates selenium in the form of selenocysteine (Sec). Most selenoproteins that have been functionally characterized are involved in oxidation-reduction (redox) reactions, with the Sec residue located at their catalytic site. To model SEPN1-RM, we generated a Sepn1-knockout (Sepn1(-/-)) mouse line. Homozygous Sepn1(-/-) mice are fertile, and their weight and lifespan are comparable to wild-type (WT) animals. Under baseline conditions, the muscle histology of Sepn1(-/-) mice remains normal, but subtle core lesions could be detected in skeletal muscle after inducing oxidative stress. Ryanodine receptor (RyR) calcium release channels showed lower sensitivity to caffeine in SepN deficient myofibers, suggesting a possible role of SepN in RyR regulation. SepN deficiency also leads to abnormal lung development characterized by enlarged alveoli, which is associated with decreased tissue elastance and increased quasi-static compliance of Sepn1(-/-) lungs. This finding raises the possibility that the respiratory syndrome observed in patients with SEPN1 mutations may have a primary pulmonary component in addition to the weakness of respiratory muscles. PMID:23325319

  2. Castration differentially alters basal and leucine-stimulated tissue protein synthesis in skeletal muscle and adipose tissue

    OpenAIRE

    Jiao, Qianning; Pruznak, Anne M.; Huber, Danuta; Vary, Thomas C; Lang, Charles H.

    2009-01-01

    Reduced testosterone as a result of catabolic illness or aging is associated with loss of muscle and increased adiposity. We hypothesized that these changes in body composition occur because of altered rates of protein synthesis under basal and nutrient-stimulated conditions that are tissue specific. The present study investigated such mechanisms in castrated male rats (75% reduction in testosterone) with demonstrated glucose intolerance. Over 9 wk, castration impaired body weight gain, which...

  3. Selenium controls sex-specific immune response and selenoprotein expression during the acute phase response in mice

    OpenAIRE

    Stoedter, Mette; Renko, Kostja; Hoeg, Antonia; Schomburg, Lutz

    2010-01-01

    Abstract Selenium modifies inflammatory reactions in rodents and humans. The liver controls metabolism and transport of selenium via hepatically-derived selenoprotein P (SEPP). Intracellular selenoprotein S (SEPS) modifies endoplasmic reticulum function and immune cell activity. Polymorphisms in SEPS were associated with cytokine levels and inflammatory diseases in a subset of clinical studies. We hypothesized that sex and selenium represent decisive parameters controlling immune r...

  4. Comparison of different transition metal ions for immobilized metal affinity chromatography of selenoprotein P from human plasma

    DEFF Research Database (Denmark)

    Sidenius, U; Farver, O; Jøns, O; Gammelgaard, Bente

    1999-01-01

    Cu2+, Ni2+, Zn2+, Co2+ and Cd2+ were evaluated in metal ion affinity chromatography for enrichment of selenoprotein P, and immobilized Co2+ affinity chromatography was found to be the most selective chromatographic method. The chromatography was performed by fast protein liquid chromatography and...... selenoprotein P. The purity of the protein was determined by SDS-PAGE and by sequencing from polyvinylidene difluoride blots of SDS-PAGE gels....

  5. Hepatic selenoprotein P (Sepp) expression restores selenium transport and prevents infertility and motor-incoordination in Sepp-knockout mice

    OpenAIRE

    Renko, Kostja; Werner, Margarethe; Renner-Müller, Ingrid; Trevor G Cooper; Yeung, Ching Hei; Hollenbach, Birgit; Scharpf, Marcus; Köhrle, Josef; Schomburg, Lutz; Schweizer, Ulrich

    2007-01-01

    Abstract Selenoprotein P (SePP) is central for selenium (Se) transport and distribution. Targeted inactivation of the Sepp gene in mice leads to reduced Se content in plasma, kidney, testis, and brain. Accordingly, activities of selenoenzymes are reduced in Sepp -/-} organs. Male Sepp -/-} mice are infertile. Unlike Se deficiency, Sepp-deficiency leads to neurological impairment with ataxia and seizures. Hepatocyte-specific inactivation of selenoprotein biosynthesis reduces plasma ...

  6. Selenoprotein Genes Exhibit Differential Expression Patterns Between Hepatoma HepG2 and Normal Hepatocytes LO2 Cell Lines.

    Science.gov (United States)

    Zhao, Hua; Tang, Jiayong; Xu, Jingyang; Cao, Lei; Jia, Gang; Long, Dingbiao; Liu, Guangmang; Chen, Xiaoling; Wang, Kangning

    2015-10-01

    The purpose of this study was to compare messenger RNA (mRNA) expression of selenoprotein genes between hepatoma HepG2 and normal hepatocytes LO2 cell lines. Liver HepG2 and LO2 cells were cultured in 12-well plates under the same condition until cells grew to complete confluence, and then cells were harvested for total RNA and protein extraction. The qPCRs were performed to compare gene expression of 14 selenoprotein genes and 5 cancer signaling-related genes. Enzyme activities were also assayed. The results showed that human hepatoma HepG2 cells grew faster than normal hepatocytes LO2 cells. Among the genes investigated, 10 selenoprotein genes (Gpx1, Gpx3, Gpx4, Selx, Sepp, Sepw1, Sepn1, Selt, Seli, Selh) and 3 cancer signaling-related genes (Bcl-2A, caspase-3, and P38) were upregulated (P < 0.05), while Selo and Bcl-2B were downregulated (P < 0.05) in hepatoma HepG2 cells compared to LO2 cells. Significant correlations were found between selenoprotein genes and the cancer signaling-related genes Caspase3, P53, Bc1-2A, and Bc1-2B. Our results revealed that selenoprotein genes were aberrantly expressed in hepatoma HepG2 cells compared to normal liver LO2 cells, which indicated that those selenoprotein genes may play important roles in the occurrence and development of liver carcinogenesis. PMID:25846212

  7. Gene-specific regulation of hepatic selenoprotein expression by interleukin-6.

    Science.gov (United States)

    Martitz, J; Becker, N-P; Renko, K; Stoedter, M; Hybsier, S; Schomburg, L

    2015-11-01

    Sepsis is a severe inflammatory disease resulting in excessive production of pro-inflammatory cytokines including interleukin-6 (IL-6), causing oxidative stress, tissue damage and organ dysfunction. Health benefits have been observed upon selenium (Se) supplementation in severe sepsis. Selenium is incorporated into selenoproteins implicated in anti-oxidative defence, thyroid hormone metabolism and immunoregulation. Selenium metabolism is controlled by hepatocytes synthesizing and secreting the Se transporter selenoprotein P (SePP). The circulating SePP declines in sepsis causing low serum Se levels. Dysregulation of the hepatic selenoenzyme deiodinase type 1 (DIO1) potentially contributes to the low T3 (thyroid hormone) syndrome observed in severe diseases. We hypothesized that IL-6 affects hepatic selenoprotein biosynthesis directly. Testing human hepatocytes in culture, IL-6 reduced the concentrations of SePP mRNA and secreted SePP in a dose-dependent manner. In parallel, expression of DIO1 declined at the mRNA, protein and enzyme activity level. The effects of IL-6 on glutathione peroxidase (GPX) expression were isozyme-specific; GPX1 remained unaffected, while transcript concentrations of GPX2 increased and those of GPX4 decreased. This pattern of IL-6-dependent effects was mirrored in reporter gene experiments with SePP, DIO1, GPX1, and GPX2 promoter constructs pointing to direct transcriptional effects of IL-6. The redirection of hepatic selenoprotein biosynthesis by IL-6 may represent a central regulatory circuit responsible for the decline of serum Se and low T3 concentrations in sepsis. Accordingly, therapeutic IL-6 targeting may be effective for improving the Se and thyroid hormone status, adjuvant Se supplementation success and survival in sepsis. PMID:26399395

  8. The Relationship between Selenoprotein P and Glucose Metabolism in Experimental Studies

    OpenAIRE

    Jinyuan Mao; Weiping Teng

    2013-01-01

    Selenium is an essential trace element in the diet of mammals which is important for many physiological functions. However, a number of epidemiological studies have suggested that high selenium status is a possible risk factor for the development of type 2 diabetes, although they cannot distinguish between cause and effect. Selenoprotein P (Sepp1) is central to selenium homeostasis and widely expressed in the organism. Here we review the interaction between Sepp1 and glucose metabolism with a...

  9. Selenoprotein P status correlates to cancer-specific mortality in renal cancer patients.

    Directory of Open Access Journals (Sweden)

    Hellmuth A Meyer

    Full Text Available Selenium (Se is an essential trace element for selenoprotein biosynthesis. Selenoproteins have been implicated in cancer risk and tumor development. Selenoprotein P (SePP serves as the major Se transport protein in blood and as reliable biomarker of Se status in marginally supplied individuals. Among the different malignancies, renal cancer is characterized by a high mortality rate. In this study, we aimed to analyze the Se status in renal cell cancer (RCC patients and whether it correlates to cancer-specific mortality. To this end, serum samples of RCC patients (n = 41 and controls (n = 21 were retrospectively analyzed. Serum Se and SePP concentrations were measured by X-ray fluorescence and an immunoassay, respectively. Clinical and survival data were compared to serum Se and SePP concentrations as markers of Se status by receiver operating characteristic (ROC curve and Kaplan-Meier and Cox regression analyses. In our patients, higher tumor grade and tumor stage at diagnosis correlated to lower SePP and Se concentrations. Kaplan-Meier analyses indicated that low Se status at diagnosis (SePP<2.4 mg/l, bottom tertile of patient group was associated with a poor 5-year survival rate of 20% only. We conclude that SePP and Se concentrations are of prognostic value in RCC and may serve as additional diagnostic biomarkers identifying a Se deficit in kidney cancer patients potentially affecting therapy regimen. As poor Se status was indicative of high mortality odds, we speculate that an adjuvant Se supplementation of Se-deficient RCC patients might be beneficial in order to stabilize their selenoprotein expression hopefully prolonging their survival. However, this assumption needs to be rigorously tested in prospective clinical trials.

  10. Increased Selenoprotein P Levels in Subjects with Visceral Obesity and Nonalcoholic Fatty Liver Disease

    OpenAIRE

    Hae Yoon Choi; Soon Young Hwang; Chang Hee Lee; Ho Cheol Hong; Sae Jeong Yang; Hye Jin Yoo; Ji A Seo; Sin Gon Kim; Nan Hee Kim; Sei Hyun Baik; Dong Seop Choi; Kyung Mook Choi

    2013-01-01

    Background Selenoprotein P (SeP) has recently been reported as a novel hepatokine that regulates insulin resistance and systemic energy metabolism in rodents and humans. We explored the associations among SeP, visceral obesity, and nonalcoholic fatty liver disease (NAFLD). Methods We examined serum SeP concentrations in subjects with increased visceral fat area (VFA) or liver fat accumulation measured with computed tomography. Our study subjects included 120 nondiabetic individuals selected f...

  11. Selenoprotein P status correlates to cancer-specific mortality in renal cancer patients.

    Science.gov (United States)

    Meyer, Hellmuth A; Endermann, Tobias; Stephan, Carsten; Stoedter, Mette; Behrends, Thomas; Wolff, Ingmar; Jung, Klaus; Schomburg, Lutz

    2012-01-01

    Selenium (Se) is an essential trace element for selenoprotein biosynthesis. Selenoproteins have been implicated in cancer risk and tumor development. Selenoprotein P (SePP) serves as the major Se transport protein in blood and as reliable biomarker of Se status in marginally supplied individuals. Among the different malignancies, renal cancer is characterized by a high mortality rate. In this study, we aimed to analyze the Se status in renal cell cancer (RCC) patients and whether it correlates to cancer-specific mortality. To this end, serum samples of RCC patients (n = 41) and controls (n = 21) were retrospectively analyzed. Serum Se and SePP concentrations were measured by X-ray fluorescence and an immunoassay, respectively. Clinical and survival data were compared to serum Se and SePP concentrations as markers of Se status by receiver operating characteristic (ROC) curve and Kaplan-Meier and Cox regression analyses. In our patients, higher tumor grade and tumor stage at diagnosis correlated to lower SePP and Se concentrations. Kaplan-Meier analyses indicated that low Se status at diagnosis (SePP<2.4 mg/l, bottom tertile of patient group) was associated with a poor 5-year survival rate of 20% only. We conclude that SePP and Se concentrations are of prognostic value in RCC and may serve as additional diagnostic biomarkers identifying a Se deficit in kidney cancer patients potentially affecting therapy regimen. As poor Se status was indicative of high mortality odds, we speculate that an adjuvant Se supplementation of Se-deficient RCC patients might be beneficial in order to stabilize their selenoprotein expression hopefully prolonging their survival. However, this assumption needs to be rigorously tested in prospective clinical trials. PMID:23056383

  12. Galectin-1 Is an Interactive Protein of Selenoprotein M in the Brain

    Directory of Open Access Journals (Sweden)

    Qiong Liu

    2013-11-01

    Full Text Available Selenium, an essential trace element for human health, mainly exerts its biological function through selenoproteins. Selenoprotein M (SelM is one of the highly expressed selenoproteins in the brain, but its biological effect and molecular mechanism remain unclear. Thus, the interactive protein of SelM was investigated in this paper to guide further study. In order to avoid protein translational stop, the selenocysteine-encoding UGA inside the open reading frame of SelM was site-directly changed to the cysteine-encoding UGC to generate the SelM' mutant. Meanwhile, its N terminal transmembrane signal peptide was also cut off. This truncated SelM' was used to screen a human fetal brain cDNA library by the yeast two-hybrid system. A new interactive protein of SelM' was found to be galectin-1 (Gal-1. This protein-protein interaction was further verified by the results of fluorescence resonance energy transfer techniques, glutathione S-transferase pull-down and co-immunoprecipitation assays. As Gal-1 plays important roles in preventing neurodegeneration and promoting neuroprotection in the brain, the interaction between SelM' and Gal-1 displays a new direction for studying the biological function of SelM in the human brain.

  13. Direct Central Nervous System Effect of Alcohol Alters Synthesis and Degradation of Skeletal Muscle Protein

    OpenAIRE

    Pruznak, Anne M; Nystrom, Jay; Lang, Charles H.

    2012-01-01

    Aims: Alcohol can directly impair protein synthesis in cultured myocytes as well as in in situ perfused skeletal muscle. However, alcohol in the general circulation diffuses rapidly into the central nervous system (CNS). Therefore, this study determined whether localized elevation of alcohol within the CNS is capable of decreasing muscle protein synthesis. Methods: Conscious unstrained male rats received a continuous intracerebroventricular (ICV) infusion of ethanol and skeletal muscle protei...

  14. Growth Model, Synthesis of Carbon nanostructures and Alteration of Surface properties Using Them

    OpenAIRE

    Naha, Sayangdev

    2008-01-01

    Flame synthesis is recognized as a much cheaper and higher throughput process for carbon nanotube/nanofiber (CNT/CNF) production compared to conventional catalytic processes like chemical vapor deposition (CVD). Nanostructured carbon materials, such as carbon nanotubes and nanofibers, exhibit superhydrophobic behavior over a range of pH values, including for corrosive liquids. Part of this research reports the development of a rapid on-demand process for the synthesis of superhydrophobic surf...

  15. Vitamin E alters alveolar type II cell phospholipid synthesis in oxygen and air

    International Nuclear Information System (INIS)

    Newborn rats were injected with vitamin E or placebo daily until 6 days after birth. The effect of vitamin E pretreatment on in vitro surfactant phospholipid synthesis was examined in isolated type II cells exposed to oxygen or air form 24 h in vitro. Type II cells were also isolated from untreated 6-day-old rats and cultured for 24 h in oxygen or air with control medium or vitamin E supplemented medium. These cells were used to examine the effect of vitamin E exposure in vitro on type II cell phospholipid synthesis and ultrastructure. Phosphatidylcholine (PC) synthesis was reduced in cells cultured in oxygen as compared with air. This decrease was not prevented by in vivo pretreatment or in vitro supplementation with vitamin E. Vitamin E pretreatment increased the ratio of disaturated PC to total PC and increased phosphatidylglycerol synthesis. The volume density of lamellar bodies in type II cells was increased in cells maintained in oxygen. Vitamin E did not affect the volume density of lamellar bodies. We conclude that in vitro hyperoxia inhibits alveolar type II cell phosphatidylcholine synthesis without decreasing lamellar body volume density and that supplemental vitamin E does not prevent hyperoxia-induced decrease in phosphatidylcholine synthesis

  16. Altered response of protein synthesis to nutritional state and endurance training in old rats.

    Science.gov (United States)

    Mosoni, L; Valluy, M C; Serrurier, B; Prugnaud, J; Obled, C; Guezennec, C Y; Mirand, P P

    1995-02-01

    This study was undertaken to determine whether the loss of muscle protein mass during aging could be explained by a reduced sensitivity of muscle protein synthesis to feeding and exercise. Male Wistar rats aged 12 and 24 mo were exercised by treadmill running for 4 mo. Protein synthesis was measured by the flooding dose method in tibialis anterior, soleus, and liver of conscious rested, trained rats and age-matched controls in the postprandial or in the postabsorptive state. No marked change with age could be detected in basal muscle protein synthesis. In contrast, protein synthesis was stimulated in adult but not in old rats by feeding in tibialis anterior and by exercise in soleus. In liver, protein synthesis was not modified by age but was stimulated by feeding and by exercise, which improved the response to feeding. We conclude that the impact of nutrition on muscle protein synthesis is blunted in old age, which could contribute to the age-related loss of nutrition-sensitive muscle proteins. PMID:7864110

  17. Vitamin E alters alveolar type II cell phospholipid synthesis in oxygen and air

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, K.A.; Snyder, J.M.; Stenzel, W.; Saito, K.; Warshaw, J.B. (Univ. of Texas Southwestern Medical School, Dallas (USA))

    1990-11-01

    Newborn rats were injected with vitamin E or placebo daily until 6 days after birth. The effect of vitamin E pretreatment on in vitro surfactant phospholipid synthesis was examined in isolated type II cells exposed to oxygen or air form 24 h in vitro. Type II cells were also isolated from untreated 6-day-old rats and cultured for 24 h in oxygen or air with control medium or vitamin E supplemented medium. These cells were used to examine the effect of vitamin E exposure in vitro on type II cell phospholipid synthesis and ultrastructure. Phosphatidylcholine (PC) synthesis was reduced in cells cultured in oxygen as compared with air. This decrease was not prevented by in vivo pretreatment or in vitro supplementation with vitamin E. Vitamin E pretreatment increased the ratio of disaturated PC to total PC and increased phosphatidylglycerol synthesis. The volume density of lamellar bodies in type II cells was increased in cells maintained in oxygen. Vitamin E did not affect the volume density of lamellar bodies. We conclude that in vitro hyperoxia inhibits alveolar type II cell phosphatidylcholine synthesis without decreasing lamellar body volume density and that supplemental vitamin E does not prevent hyperoxia-induced decrease in phosphatidylcholine synthesis.

  18. Altered synthesis of glucosamine-labelled glycopeptides during postimplantation embryogenesis of the mouse

    International Nuclear Information System (INIS)

    Dissected mouse embryos were examined for the ability to synthesize (3H)glucosamine-labeled embryoglycan, which is the glycoprotein-bound large carbohydrate eluted near the excluded volume of a Sephadex G-50 column. Although the ratio of glucosamine-label incorporated into embryoglycan decreased progressively during embryogenesis, 11- and 12-day-old embryos still synthesized significant amounts of the glycan. Severe inhibition of the glycan synthesis was noticed after the 15th day. Therefore, synthesis of the core portion of embryoglycan was suppressed later than when fucosylation of the glycan was known to be suppressed. (author)

  19. Study of nuclear glasses alteration gel and synthesis of some model gels

    International Nuclear Information System (INIS)

    This work deals with the general problem of alteration of the reference nuclear glass R7T7. Attention is paid particularly to the altered layer formed at the glass surface during alteration process. In opposition to previous works, related essentially to glass dissolution kinetics based on chemical analyses of lixiviated elements, this thesis deals with alteration problems through structural studies of the reference glass and derived gel. This approach allows the determination of mechanisms for the gel formation and a better understanding of the behaviour of glasses towards lixiviation. Both approaches appeared complementary. Based on several spectroscopic techniques, this work showed the particular role of cations such as calcium, zirconium and iron. Studies of silica-based synthetic gels showed the synergic effect of formers cation and of one highly coordinated cation. The variation of the wavenumber related to Si-O-Si asymmetric stretching vibration can be correlated to O/Si ratio for ternary systems Si/Na/Zr. On the contrary, the Si losses of the materials depend on the number of non-bridging oxygen atoms. In the perspective of long-term behaviour, the alteration gel presents better characteristics than initial glass. It is therefore a highly stable material in static conditions. In the same way, synthetic gels are materials with very low solubilities (much lower than the alteration gel) and could be used as confining matrices. (authors). refs., 71 figs., 37 tabs

  20. Myocardial Reloading after Extracorporeal Membrane Oxygenation Alters Substrate Metabolism While Promoting Protein Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Kajimoto, Masaki; Priddy, Colleen M.; Ledee, Dolena; Xu, Chun; Isern, Nancy G.; Olson, Aaron; Des Rosiers, Christine; Portman, Michael A.

    2013-08-19

    Extracorporeal membrane oxygenation (ECMO) unloads the heart providing a bridge to recovery in children after myocardial stunning. Mortality after ECMO remains high.Cardiac substrate and amino acid requirements upon weaning are unknown and may impact recovery. We assessed the hypothesis that ventricular reloading modulates both substrate entry into the citric acid cycle (CAC) and myocardial protein synthesis. Fourteen immature piglets (7.8-15.6 kg) were separated into 2 groups based on ventricular loading status: 8 hour-ECMO (UNLOAD) and post-wean from ECMO (RELOAD). We infused [2-13C]-pyruvate as an oxidative substrate and [13C6]-L-leucine, as a tracer of amino acid oxidation and protein synthesis into the coronary artery. RELOAD showed marked elevations in myocardial oxygen consumption above baseline and UNLOAD. Pyruvate uptake was markedly increased though RELOAD decreased pyruvate contribution to oxidative CAC metabolism.RELOAD also increased absolute concentrations of all CAC intermediates, while maintaining or increasing 13C-molar percent enrichment. RELOAD also significantly increased cardiac fractional protein synthesis rates by >70% over UNLOAD. Conclusions: RELOAD produced high energy metabolic requirement and rebound protein synthesis. Relative pyruvate decarboxylation decreased with RELOAD while promoting anaplerotic pyruvate carboxylation and amino acid incorporation into protein rather than to the CAC for oxidation. These perturbations may serve as therapeutic targets to improve contractile function after ECMO.

  1. Selenium status affects selenoprotein expression, reproduction, and F₁ generation locomotor activity in zebrafish (Danio rerio).

    Science.gov (United States)

    Penglase, Sam; Hamre, Kristin; Rasinger, Josef D; Ellingsen, Staale

    2014-06-14

    Se is an essential trace element, and is incorporated into selenoproteins which play important roles in human health. Mammalian selenoprotein-coding genes are often present as paralogues in teleost fish, and it is unclear whether the expression patterns or functions of these fish paralogues reflect their mammalian orthologues. Using the model species zebrafish (Danio rerio; ZF), we aimed to assess how dietary Se affects key parameters in Se metabolism and utilisation including glutathione peroxidase (GPX) activity, the mRNA expression of key Se-dependent proteins (gpx1a, gpx1b, sepp1a and sepp1b), oxidative status, reproductive success and F1 generation locomotor activity. From 27 d until 254 d post-fertilisation, ZF were fed diets with graded levels of Se ranging from deficient ( < 0·10 mg/kg) to toxic (30 mg/kg). The mRNA expression of gpx1a and gpx1b and GPX activity responded in a similar manner to changes in Se status. GPX activity and mRNA levels were lowest when dietary Se levels (0·3 mg/kg) resulted in the maximum growth of ZF, and a proposed bimodal mechanism in response to Se status below and above this dietary Se level was identified. The expression of the sepp1 paralogues differed, with only sepp1a responding to Se status. High dietary Se supplementation (30 mg/kg) decreased reproductive success, while the offspring of ZF fed above 0·3 mg Se/kg diet had lower locomotor activity than the other groups. Overall, the novel finding of low selenoprotein expression and activity coinciding with maximum body growth suggests that even small Se-induced variations in redox status may influence cellular growth rates. PMID:24666596

  2. Genetic Variation in Selenoprotein Genes, Lifestyle, and Risk of Colon and Rectal Cancer

    OpenAIRE

    Martha L Slattery; Lundgreen, Abbie; Welbourn, Bill; Corcoran, Christopher; Wolff, Roger K.

    2012-01-01

    Background Associations between selenium and cancer have directed attention to role of selenoproteins in the carcinogenic process. Methods We used data from two population-based case-control studies of colon (n = 1555 cases, 1956 controls) and rectal (n = 754 cases, 959 controls) cancer. We evaluated the association between genetic variation in TXNRD1, TXNRD2, TXNRD3, C11orf31 (SelH), SelW, SelN1, SelS, SepX, and SeP15 with colorectal cancer risk. Results After adjustment for multiple compari...

  3. Selenoprotein S/SEPS1 Modifies Endoplasmic Reticulum Stress in Z Variant α1-Antitrypsin Deficiency*

    OpenAIRE

    Kelly, Emer; Catherine M. Greene; Carroll, Tomás P; Noel G. McElvaney; O'Neill, Shane J

    2009-01-01

    Z α1-antitrypsin (ZAAT) deficiency is a disease associated with emphysematous lung disease and also with liver disease. The liver disease of AAT deficiency is associated with endoplasmic reticulum (ER) stress. SEPS1 is a selenoprotein that, through a chaperone activity, decreases ER stress. To determine the effect of SEPS1 on ER stress in ZAAT deficiency, we measured activity of the grp78 promoter and levels of active ATF6 as markers of the unfolded protein response in HepG2 cells transfected...

  4. Polymorphisms in the selenoprotein S gene: lack of association with autoimmune inflammatory diseases

    OpenAIRE

    Díaz-Rubio Manuel; de la Calle Hermenegildo; Mendoza Juan; Lamas José; Márquez Ana; Varadé Jezabel; Santiago Jose; Martínez Alfonso; de la Concha Emilio G; Fernández-Gutiérrez Benjamín; Urcelay Elena

    2008-01-01

    Abstract Background Selenoprotein S (SelS) protects the functional integrity of the endoplasmic reticulum against the deleterious effects of metabolic stress. SEPS1/SelS polymorphisms have been involved in the increased release of pro-inflammatory cytokines interleukin (IL)-1β, tumor necrosis factor (TNF)-α and IL-6 in macrophages. We aimed at investigating the role of the SEPS1 variants previously associated with higher plasma levels of these cytokines and of the SEPS1 haplotypes in the susc...

  5. Direct determination of selenoproteins in polyvinylidene difluoride membranes by electrothermal atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Sidenius, U; Gammelgaard, Bente

    2000-01-01

    A method for the direct determination of selenoproteins in plastic membranes after protein separation by gel electrophoresis was developed. Quantification was based on the determination of the selenium content of the proteins by electrothermal atomic absorption spectrometry (ET-AAS) after manual...... were excised and chemical modifier was added on top of the excised membrane prior to atomic absorption measurement. Acceptable linearity was achieved in the range 2-10 ng Se, corresponding to selenium concentrations close to 1 mg/L, when aqueous solutions of selenomethionine standard as well as...

  6. Direct Interaction of Selenoprotein R with Clusterin and Its Possible Role in Alzheimer’s Disease

    OpenAIRE

    Chen, Ping; Wang, Chao; Ma, Xiaojie; Zhang, Yizhe; Liu, Qing; Qiu, Shi; Liu, Qiong; Tian, Jing; Ni, Jiazuan

    2013-01-01

    Selenoprotein R (SelR) plays an important role in maintaining intracellular redox balance by reducing the R-form of methionine sulfoxide to methionine. As SelR is highly expressed in brain and closely related to Alzheimer′s disease (AD), its biological functions in human brain become a research focus. In this paper, the selenocysteine-coding TGA of SelR gene was mutated to cysteine-coding TGC and used to screen the human fetal brain cDNA library with a yeast two-hybrid system. Our results dem...

  7. Altered pattern of brain dopamine synthesis in male adolescents with attention deficit hyperactivity disorder

    OpenAIRE

    Waters Nicholas; Waters Susanna; Fernell Elisabeth; Forssberg Hans; Tedroff Joakim

    2006-01-01

    Abstract Background Limited data from positron emission tomography (PET) studies of subjects with attention-deficit/hyperactivity disorder (ADHD) indicate alterations in brain dopamine neurotransmission. However, these studies have used conventional univariate approaches that are less sensitive to detect complex interactions that may exist between different brain dopamine pathways and individual symptoms of ADHD. We aimed to investigate these potential interactions in adolescents with ADHD. M...

  8. Altered turnover and synthesis rates of lung surfactant following thoracic irradiation

    International Nuclear Information System (INIS)

    Between 2-6 weeks after thoracic irradiation with 10 Gy X rays, when levels of surfactant in the alveoli show the greatest increase, there is a reduction in the rate of radioactivity loss from 3H-choline labeled disaturated phosphatidylcholine from the lung. This indicates a reduced turnover of surfactant. Discrepancies between the halving times for specific activity and for total radioactivity of the disaturated phospholipids suggest that at between 2 and 3 weeks post-irradiation, removal and degradation of surfactant almost ceases, but that synthesis continues normally. However, by 3 weeks post-irradiation, choline-3H incorporation into disaturated phosphatidylcholine suggests that surfactant synthesis is increased about two-fold. The reduced number of macrophages recovered from alveolar lavage between about 2 and 6 weeks post-irradiation may indicate a reason for the lengthened turnover times of surfactant over this period. Nevertheless, the stimulated surfactant production that takes place from about 3 weeks onward suggests an additional active response to radiation or to radiation damage by the type II pneumonocytes. These studies confirm that the maximum levels of alveolar surfactant seen at 3 weeks post-irradiation result from a different lung response than that responsible for the increase in surfactant, which occurs within hours of irradiation

  9. Impaired Homocysteine Transmethylation and Protein-Methyltransferase Activity Reduce Expression of Selenoprotein P: Implications for Obesity and Metabolic Syndrome

    Science.gov (United States)

    Obesity causes Metabolic Syndrome and Type-II Diabetes, disrupting hepatic function, methionine (Met)/homocysteine (Hcy) transmethylation and methyltransferase (PRMT) activities. Selenoprotein P (SEPP1), exported from the liver, is the predominate form of plasma selenium (Se) and the physiological S...

  10. Kissing loops hide premature termination codons in pre-mRNAof selenoprotein genes and in genes containing programmedribosomal frameshifts

    DEFF Research Database (Denmark)

    Knudsen, Steen; Brunak, Søren

    1997-01-01

    A novel RNA secondary structure that places the selenocysteine codon UGA in one hairpin and a donor splice site in another, has been discovered in selenoprotein genes. The presence of the structure resolves the discrepancy that the selenocysteine triplet, UGA, should block splicing. Without a spe...

  11. Association between Polymorphisms in Glutathione Peroxidase and Selenoprotein P Genes, Glutathione Peroxidase Activity, HRT Use and Breast Cancer Risk

    DEFF Research Database (Denmark)

    Méplan, Catherine; Dragsted, Lars Ove; Ravn-Haren, Gitte;

    2013-01-01

    Breast cancer (BC) is one of the most common cancers in women. Evidence suggests that genetic variation in antioxidant enzymes could influence BC risk, but to date the relationship between selenoproteins and BC risk remains unclear. In this report, a study population including 975 Danish cases an...

  12. Assessment of the Selenoprotein M (SELM over-expression on human hepatocellular carcinoma tissues by immunohistochemistry

    Directory of Open Access Journals (Sweden)

    E. Guerriero

    2014-10-01

    Full Text Available Selenium is an essential trace mineral of fundamental importance to human healthy and exerts its biological function through selenoproteins. In particular, Selenoprotein M (SELM is located in the endoplasmic reticulum and contains the common redox motif of cysteine-X-X-selenocysteine type. It attracts great attention due to its high expression in brain and its potential roles as antioxidant, neuroprotective, and cytosolic calcium regulator. Recently, our group found SELM over-expression  in human hepatocellular carcinoma (HCC cell lines. In this report some paraffin-embedded tissues from liver biopsy of patients with hepatitis C virus (HCV-related cirrhosis and HCC were immunohistochemically stained and SELM expression scoring was evaluated. Our results evidence for the first time an increase of SELM expression in HCC liver tissues, and its gradual expression raise associated with an increased malignancy grade. Therefore, we propose to use i SELM as putative marker for HCC as well as ii simple immunohistochemistry technique to distinguish between the different grades of malignancy. 

  13. Selenoprotein P influences colitis-induced tumorigenesis by mediating stemness and oxidative damage

    Science.gov (United States)

    Barrett, Caitlyn W.; Reddy, Vishruth K.; Short, Sarah P.; Motley, Amy K.; Lintel, Mary K.; Bradley, Amber M.; Freeman, Tanner; Vallance, Jefferson; Ning, Wei; Parang, Bobak; Poindexter, Shenika V.; Fingleton, Barbara; Chen, Xi; Washington, Mary K.; Wilson, Keith T.; Shroyer, Noah F.; Hill, Kristina E.; Burk, Raymond F.; Williams, Christopher S.

    2015-01-01

    Patients with inflammatory bowel disease are at increased risk for colon cancer due to augmented oxidative stress. These patients also have compromised antioxidant defenses as the result of nutritional deficiencies. The micronutrient selenium is essential for selenoprotein production and is transported from the liver to target tissues via selenoprotein P (SEPP1). Target tissues also produce SEPP1, which is thought to possess an endogenous antioxidant function. Here, we have shown that mice with Sepp1 haploinsufficiency or mutations that disrupt either the selenium transport or the enzymatic domain of SEPP1 exhibit increased colitis-associated carcinogenesis as the result of increased genomic instability and promotion of a protumorigenic microenvironment. Reduced SEPP1 function markedly increased M2-polarized macrophages, indicating a role for SEPP1 in macrophage polarization and immune function. Furthermore, compared with partial loss, complete loss of SEPP1 substantially reduced tumor burden, in part due to increased apoptosis. Using intestinal organoid cultures, we found that, compared with those from WT animals, Sepp1-null cultures display increased stem cell characteristics that are coupled with increased ROS production, DNA damage, proliferation, decreased cell survival, and modulation of WNT signaling in response to H2O2-mediated oxidative stress. Together, these data demonstrate that SEPP1 influences inflammatory tumorigenesis by affecting genomic stability, the inflammatory microenvironment, and epithelial stem cell functions. PMID:26053663

  14. Altered synthesis of some secretory proteins in pancreatic lobules isolated from streptozotocin-induced diabetic rats

    International Nuclear Information System (INIS)

    The in vitro incorporation of [35S]cysteine into lipase, colipase, amylase, procarboxypeptidase A and B, and the serine proteases and total proteins was studied in pancreatic lobules isolated from normal and diabetic rats with or without insulin treatment. The incorporation of [35S]cysteine into total proteins was 65% greater in pancreatic lobules from diabetic animals than from normal rats. The increased incorporation was partly reversed by insulin treatment (2 U/100 g/day for 5 days) of diabetic rats. The relative rates of biosynthesis for amylase and the procarboxypeptidases in diabetic pancreatic lobules were decreased by 75 and 25%, respectively, after 1 h of incubation, while those for lipase, colipase, and the serine proteases were increased by 90, 85, and 35%, respectively. The absolute rates of synthesis for these enzymes changed in the same direction as the relative rates in diabetic lobules, except that for the procarboxypeptidases, which did not change. The changed rates of biosynthesis for the pancreatic enzymes were reversed by insulin treatment of the diabetic rats. Kinetic studies showed that the incorporation of [35S]cysteine into amylase, lipase, and colipase was linear until up to 2 h of incubation in normal pancreatic lobules, while in the diabetic lobules the incorporation into lipase and colipase was accelerated, reaching a plateau level already after 1 h of incubation. It is concluded that the biosynthesis of pancreatic secretory proteins in diabetic rats is greatly changed both in terms of quantity and kinetics

  15. Metabolic engineering of the morphology of Aspergillus oryzae by altering chitin synthesis

    DEFF Research Database (Denmark)

    Muller, C.; Mcintyre, Mhairi; Hansen, Kim; Nielsen, Jens

    2002-01-01

    than that in the wild type., whereas that in the ChsB/G strain was 188% higher. During batch cultivation, inseparable clumps were formed in the wild-type strain., while no or fewer large inseparable clumps existed in the cultivations of the ChsB/G and CM101 strains. The alpha-amylase productivity was......Morphology and alpha-amylase production during submerged cultivation were examined in a wild-type strain (A1560) and in strains of Aspergillus oryzae in which chitin synthase B (chsB) and chitin synthesis myosin A (csmA) have been disrupted (ChsB/G and CM101). In a flowthrough cell, the growth of...... not significantly different in the three strains. A strain in which the transcription of chsB could be controlled by the nitrogen source-regulated promoter niiA (NiiA1) was examined during chemostat cultivation, and it was found that the branching intensity could be regulated by regulating the...

  16. Specific genes involved in synthesis and editing of heparan sulfate proteoglycans show altered expression patterns in breast cancer

    International Nuclear Information System (INIS)

    The expression of a specific set of genes controls the different structures of heparan sulfate proteoglycans (HSPGs), which are involved in the growth, invasion and metastatic properties of cancerous cells. The purpose of this study is to increase knowledge of HSPG alterations in breast cancer. Twenty-three infiltrating ductal adenocarcinomas (IDCs), both metastatic and non-metastatic were studied. A transcriptomic approach to the structure of heparan sulfate (HS) chains was used, employing qPCR to analyze both the expression of the enzymes involved in their biosynthesis and editing, as well as the proteoglycan core proteins. Since some of these proteoglycans can also carry chondroitin sulfate chains, we extended the study to include the genes involved in the biosynthesis of these glycosaminoglycans. Histochemical techniques were also used to analyze tissular expression of particular genes showing significant expression differences, of potential interest. No significant change in transcription was detected in approximately 70% of analyzed genes. However, 13 demonstrated changes in both tumor types (40% showing more intense deregulation in the metastatic), while 5 genes showed changes only in non-metastatic tumors. Changes were related to 3 core proteins: overexpression of syndecan-1 and underexpression of glypican-3 and perlecan. HS synthesis was affected by lower levels of some 3-O-sulfotransferase transcripts, the expression of NDST4 and, only in non metastatic tumors, higher levels of extracellular sulfatases. Furthermore, the expression of chondroitin sulfate also was considerably affected, involving both the synthesis of the saccharidic chains and sulfations at all locations. However, the pro-metastatic enzyme heparanase did not exhibit significant changes in mRNA expression, although in metastatic tumors it appeared related to increased levels of the most stable form of mRNA. Finally, the expression of heparanase 2, which displays anti-metastatic features

  17. Contribution of various carbon sources toward isoprene synthesis mediated by altered atmospheric CO2 concentrations

    Science.gov (United States)

    Trowbridge, A. M.; Asensio, D.; Eller, A. S.; Wilkinson, M. J.; Schnitzler, J.; Jackson, R. B.; Monson, R. K.

    2010-12-01

    Biogenically released isoprene is abundant in the troposphere, and has an essential function in determining atmospheric chemistry and important implications for plant metabolism. As a result, considerable effort has been made to understand the underlying mechanisms driving isoprene synthesis, particularly in the context of a rapidly changing environment. Recently, a number of studies have focused on the contribution of recently assimilated carbon as opposed to stored/alternative intracellular or extracellular carbon sources in the context of environmental stress. Results from these studies can offer clues about the importance of various carbon pools for isoprene production and elucidate the corresponding physiological changes that are responsible for these dynamic shifts in carbon allocation. We performed a 13CO2-labeling study using proton-transfer-reaction mass spectrometry (PTR-MS) to examine the kinetics of the incorporation of recently assimilated photosynthate into isoprene emitted from poplar (Poplar x canescens) under sub-ambient, ambient, and elevated CO2 growth conditions. We also monitored the importance of pyruvate-derived carbon for isoprene biosynthesis and obtained a detailed account of where individual carbons are derived from by analyzing the ratio of the 3C subunit of isoprene (M41+) (a fragment which contains two carbons from pyruvate) to the ratio of the parent isoprene molecule (M69+). Dynamics in the M41+:M69+ ratio indicate that recently assimilated carbon is incorporated into the pyruvate carbon pool slowly across all CO2 treatments and is therefore accessible for isoprene synthesis at a slower rate when compared to substrates derived directly from photosynthesis. Analysis of the rates of change for individual masses indicated that the carbon pools in trees grown in sub-ambient CO2 (200 ppm) are labeled ~2 times faster than those of trees grown in ambient or elevated CO2. Analysis of the total isoprene emission rates between treatments

  18. Metabolic engineering of the morphology of Aspergillus oryzae by altering chitin synthesis.

    Science.gov (United States)

    Müller, Christian; McIntyre, Mhairi; Hansen, Kim; Nielsen, Jens

    2002-04-01

    Morphology and alpha-amylase production during submerged cultivation were examined in a wild-type strain (A1560) and in strains of Aspergillus oryzae in which chitin synthase B (chsB) and chitin synthesis myosin A (csmA) have been disrupted (ChsB/G and CM101). In a flowthrough cell, the growth of submerged hyphal elements was studied online, making it possible to examine the growth kinetics of the three strains. The average tip extension rates of the CM101 and ChsB/G strains were 25 and 88% lower, respectively, than that of the wild type. The branching intensity in the CM101 strain was 25% lower than that in the wild type, whereas that in the ChsB/G strain was 188% higher. During batch cultivation, inseparable clumps were formed in the wild-type strain, while no or fewer large inseparable clumps existed in the cultivations of the ChsB/G and CM101 strains. The alpha-amylase productivity was not significantly different in the three strains. A strain in which the transcription of chsB could be controlled by the nitrogen source-regulated promoter niiA (NiiA1) was examined during chemostat cultivation, and it was found that the branching intensity could be regulated by regulating the promoter, signifying an important role for chsB in branching. However, the pattern of branching responded very slowly to the change in transcription, and increased branching did not affect alpha-amylase productivity. alpha-Amylase residing in the cell wall was stained by immunofluorescence, and the relationship between tip number and enzyme secretion is discussed. PMID:11916702

  19. Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis

    Science.gov (United States)

    Areta, José L; Burke, Louise M; Ross, Megan L; Camera, Donny M; West, Daniel W D; Broad, Elizabeth M; Jeacocke, Nikki A; Moore, Daniel R; Stellingwerff, Trent; Phillips, Stuart M; Hawley, John A; Coffey, Vernon G

    2013-01-01

    Quantity and timing of protein ingestion are major factors regulating myofibrillar protein synthesis (MPS). However, the effect of specific ingestion patterns on MPS throughout a 12 h period is unknown. We determined how different distributions of protein feeding during 12 h recovery after resistance exercise affects anabolic responses in skeletal muscle. Twenty-four healthy trained males were assigned to three groups (n= 8/group) and undertook a bout of resistance exercise followed by ingestion of 80 g of whey protein throughout 12 h recovery in one of the following protocols: 8 × 10 g every 1.5 h (PULSE); 4 × 20 g every 3 h (intermediate: INT); or 2 × 40 g every 6 h (BOLUS). Muscle biopsies were obtained at rest and after 1, 4, 6, 7 and 12 h post exercise. Resting and post-exercise MPS (l-[ring-13C6] phenylalanine), and muscle mRNA abundance and cell signalling were assessed. All ingestion protocols increased MPS above rest throughout 1–12 h recovery (88–148%, P INT>PULSE hierarchy in magnitude of phosphorylation. MuRF-1 and SLC38A2 mRNA were differentially expressed with BOLUS. In conclusion, 20 g of whey protein consumed every 3 h was superior to either PULSE or BOLUS feeding patterns for stimulating MPS throughout the day. This study provides novel information on the effect of modulating the distribution of protein intake on anabolic responses in skeletal muscle and has the potential to maximize outcomes of resistance training for attaining peak muscle mass. PMID:23459753

  20. Altered pattern of brain dopamine synthesis in male adolescents with attention deficit hyperactivity disorder

    Directory of Open Access Journals (Sweden)

    Waters Nicholas

    2006-12-01

    Full Text Available Abstract Background Limited data from positron emission tomography (PET studies of subjects with attention-deficit/hyperactivity disorder (ADHD indicate alterations in brain dopamine neurotransmission. However, these studies have used conventional univariate approaches that are less sensitive to detect complex interactions that may exist between different brain dopamine pathways and individual symptoms of ADHD. We aimed to investigate these potential interactions in adolescents with ADHD. Methods We used a 3D PET scan to measure utilization of native L-[11C]-DOPA to map dopamine presynaptic function in various cortical, striatal and midbrain regions in a group of 8 male adolescents with ADHD and 6 age matched controls. To evaluate the interactions between the studied brain regions, multivariate statistical methods were used. Results Abnormal dopaminergic function was found in multiple brain regions of patients with ADHD. A main finding was lower L-[11C]-DOPA utilization in adolescent with ADHD as compared to control subjects, especially in subcortical regions. This pattern of dopaminergic activity was correlated specifically with symptoms of inattention. Conclusion Dopamine signalling in the brain plays an important modulatory role in a variety of motor and cognitive functions. We have identified region-specific functional abnormalities in dopaminergic function, which may help better account for the symptoms of ADHD.

  1. The human selenoprotein VCP-interacting membrane protein (VIMP) is non-globular and harbors a reductase function in an intrinsically disordered region

    DEFF Research Database (Denmark)

    Christensen, Lea Cecilie; Jensen, Njal Winther; Lages Lino Vala, Andrea;

    2012-01-01

    The human selenoprotein VIMP (VCP-interacting membrane protein)/SelS (selenoprotein S) localizes to the endoplasmic reticulum (ER) membrane and is involved in the process of ER-associated degradation (ERAD). To date, little is known about the presumed redox activity of VIMP, its structure and how...... reductase, and we speculate that the plasticity of the intrinsically disordered C-terminal region allows the protein to access many different and structurally diverse substrates....

  2. Alteration Information Extraction by Applying Synthesis Processing Techniques to Landsat ETM+Data: Case Study of Zhaoyuan Gold Mines,Shandong Province, China

    Institute of Scientific and Technical Information of China (English)

    Liu Fujiang; Wu Xincai; Sun Huashan; Guo Yan

    2007-01-01

    Satellite remote sensing data are usually used to analyze the spatial distribution pattern of geological structures and generally serve as a significant means for the identification of alteration zones. Based on the Landsat Enhanced Thematic Mapper (ETM+) data, which have better spectral resolution (8 bands) and spatial resolution (15 m in PAN band), the synthesis processing techniques were presented to fulfill alteration information extraction: data preparation, vegetation indices and band ratios, and expert classifier-based classification. These techniques have been implemented in the MapGIS-RSP software (version 1.0), developed by the Wuhan Zondy Cyber Technology Co., Ltd,China. In the study area application of extracting alteration information in the Zhaoyuan (招远) gold mines, Shandong (山东) Province, China, several hydorthermally altered zones (included two new sites) were found after satellite imagery interpretation coupled with field surveys. It is concluded that these synthesis processing techniques are useful approaches and are applicable to a wide range of gold-mineralized alteration information extraction.

  3. Study of nuclear glasses alteration gel and synthesis of some model gels; Etude du gel d`alteration des verres nucleaires et synthese de gels modeles

    Energy Technology Data Exchange (ETDEWEB)

    Ricol, S.

    1995-10-05

    This work deals with the general problem of alteration of the reference nuclear glass R7T7. Attention is paid particularly to the altered layer formed at the glass surface during alteration process. In opposition to previous works, related essentially to glass dissolution kinetics based on chemical analyses of lixiviated elements, this thesis deals with alteration problems through structural studies of the reference glass and derived gel. This approach allows the determination of mechanisms for the gel formation and a better understanding of the behaviour of glasses towards lixiviation. Both approaches appeared complementary. Based on several spectroscopic techniques, this work showed the particular role of cations such as calcium, zirconium and iron. Studies of silica-based synthetic gels showed the synergic effect of formers cation and of one highly coordinated cation. The variation of the wavenumber related to Si-O-Si asymmetric stretching vibration can be correlated to O/Si ratio for ternary systems Si/Na/Zr. On the contrary, the Si losses of the materials depend on the number of non-bridging oxygen atoms. In the perspective of long-term behaviour, the alteration gel presents better characteristics than initial glass. It is therefore a highly stable material in static conditions. In the same way, synthetic gels are materials with very low solubilities (much lower than the alteration gel) and could be used as confining matrices. (authors). refs., 71 figs., 37 tabs.

  4. Selenoprotein W was Correlated with the Protective Effect of Selenium on Chicken Myocardial Cells from Oxidative Damage.

    Science.gov (United States)

    Liu, Wei; Yao, Haidong; Zhao, Wenchao; Shi, Yuguang; Zhang, Ziwei; Xu, Shiwen

    2016-06-01

    Selenium (Se) mainly performs its function through Se-containing proteins. Selenoprotein W (SelW), one member of the selenoprotein family, plays important roles in the normal function of the heart. To investigate the possible relationship between Se and SelW for the regulation of oxidative damage in chicken embryo myocardial cells, we treated myocardial cells with Se and H2O2. Then, the levels of lactate dehydrogenase (LDH) and 3,4-methylenedioxyamphetamine in the culture media, levels of SelW, inflammatory genes NF-κB, tumor necrosis factor (TNF)-α, p53, and the cell cycle were analyzed. Furthermore, the correlation between SelW and the levels of these factors was determined. The results indicated that Se treatment increased the expression of SelW (P chicken myocardial cells. PMID:26463750

  5. Glutathione enzyme and selenoprotein polymorphisms associate with mercury biomarker levels in Michigan dental professionals

    International Nuclear Information System (INIS)

    Mercury is a potent toxicant of concern to both the general public and occupationally exposed workers (e.g., dentists). Recent studies suggest that several genes mediating the toxicokinetics of mercury are polymorphic in humans and may influence inter-individual variability in mercury accumulation. This work hypothesizes that polymorphisms in key glutathione synthesizing enzyme, glutathione s-transferase, and selenoprotein genes underlie inter-individual differences in mercury body burden as assessed by analytical mercury measurement in urine and hair, biomarkers of elemental mercury and methylmercury, respectively. Urine and hair samples were collected from a population of dental professionals (n = 515), and total mercury content was measured. Average urine (1.06 ± 1.24 ug/L) and hair mercury levels (0.49 ± 0.63 ug/g) were similar to national U.S. population averages. Taqman assays were used to genotype DNA from buccal swab samples at 15 polymorphic sites in genes implicated in mercury metabolism. Linear regression modeling assessed the ability of polymorphisms to modify the relationship between mercury biomarker levels and exposure sources (e.g., amalgams, fish consumption). Five polymorphisms were significantly associated with urine mercury levels (GSTT1 deletion), hair mercury levels (GSTP1-105, GSTP1-114, GSS 5′), or both (SEPP1 3′UTR). Overall, this study suggests that polymorphisms in selenoproteins and glutathione-related genes may influence elimination of mercury in the urine and hair or mercury retention following exposures to elemental mercury (via dental amalgams) and methylmercury (via fish consumption). -- Highlights: ► We explore the influence of 15 polymorphisms on urine and hair Hg levels. ► Urine and hair Hg levels in dental professionals were similar to the US population. ► GSTT1 and SEPP1 polymorphisms associated with urine Hg levels. ► Accumulation of Hg in hair following exposure from fish was modified by genotype. ► GSTP1, GSS

  6. Evaluation of Selenite Effects on Selenoproteins and Cytokinome in Human Hepatoma Cell Lines

    Directory of Open Access Journals (Sweden)

    Susan Costantini

    2013-02-01

    Full Text Available The need to explore new alternative therapeutic strategies and chemoprevention methods for hepatocellular carcinoma is growing significantly. Selenium is a trace element that plays a critical role in physiological processes, and is used in cancer chemoprevention. The aim of this work was to test in vitro the effect of sodium selenite on the human hepatoma cell lines, HepG2 and Huh7, to assess its effect on the expression of GPX1, SELK and SELENBP1 and also to evaluate its action on inflammation determinants such as cytokines. Our results show that: (i the increase observed for the GPX1 and SELK expression is correlated with an increase in the sodium selenite concentration, also evidencing an inverse association between the levels of these two proteins and SELENBP1; (ii the selenium concentrations evaluated in protein extracts increase in proportional way with the selenite concentrations used in the treatment, suggesting that other selenoproteins can also be modulated and should be evaluated in further studies, and (iii some cytokines, VEGF and three pro-inflammatory cytokines, i.e., IL-6, IL-8, and IL-17, decreased with an increasing selenite concentration. Finally, interactomic studies show that GPX1 and SELK, and the four pro-inflammatory cytokines are functionally correlated evidencing a putative anti-inflammatory role for the selenite.

  7. Selenoprotein S/SEPS1 modifies endoplasmic reticulum stress in Z variant alpha1-antitrypsin deficiency.

    LENUS (Irish Health Repository)

    Kelly, Emer

    2009-06-19

    Z alpha(1)-antitrypsin (ZAAT) deficiency is a disease associated with emphysematous lung disease and also with liver disease. The liver disease of AAT deficiency is associated with endoplasmic reticulum (ER) stress. SEPS1 is a selenoprotein that, through a chaperone activity, decreases ER stress. To determine the effect of SEPS1 on ER stress in ZAAT deficiency, we measured activity of the grp78 promoter and levels of active ATF6 as markers of the unfolded protein response in HepG2 cells transfected with the mutant form of AAT, a ZAAT transgene. We evaluated levels of NFkappaB activity as a marker of the ER overload response. To determine the effect of selenium supplementation on the function of SEPS1, we investigated glutathione peroxidase activity, grp78 promoter activity, and NFkappaB activity in the presence or absence of selenium. SEPS1 reduced levels of active ATF6. Overexpression of SEPS1 also inhibited grp78 promoter and NFkappaB activity, and this effect was enhanced in the presence of selenium supplementation. This finding demonstrates a role for SEPS1 in ZAAT deficiency and suggests a possible therapeutic potential for selenium supplementation.

  8. Association of selenoprotein S gene polymorphism with ischemic stroke in a Chinese case-control study.

    Science.gov (United States)

    Li, Xiao-Xia; Guan, Hong-Jun; Liu, Jian-Ping; Guo, Yu-Peng; Yang, Yong; Niu, Ying-Ying; Yao, Li-Yan; Yang, Yin-Dong; Yue, Hong-Yu; Meng, Li-Li; Cui, Xin-Yu; Yang, Xiao-Wei; Gao, Jin-Xiao

    2015-03-01

    Previous studies showed that selenoprotein S (SELS) was associated with a range of inflammatory markers, and its gene expression was influenced by a polymorphism in the promoter region. The genetic basis of the ischemic stroke has now been largely determined, so the aim of the study was to examine the role of SELS genetic variants in the ischemic stroke risk in a Chinese population. We conducted a case-control study with 239 ischemic stroke patients and 240 controls. Two single-nucleotide polymorphisms (SNPs) in SELS genes were analyzed for association with the risk of ischemic stroke in the Chinese Han population. No evidence of ischemic stroke association was observed with the SNP rs34713741. Interestingly, the strongest evidence showed that SELS SNP rs4965814 was associated with ischemic stroke (P hazard ratio: 2.43(1.03-5.75)]; a similar trend was also found in men carrying the TC genotype of rs4965814 [hazard ratio: 1.81(1.06-3.08)]. SNP rs4965814 of SELS may affect the susceptibility to ischemic stroke. Understanding the inflammatory mechanisms of ischemic stroke may give new therapeutic targets to pharmacologists. PMID:25390504

  9. Characterization of Selenoprotein M and Its Response to Selenium Deficiency in Chicken Brain.

    Science.gov (United States)

    Huang, Jia-Qiang; Ren, Fa-Zheng; Jiang, Yun-Yun; Lei, XinGen

    2016-04-01

    Selenoprotein M (SelM) may function as thiol disulfide oxidoreductase that participates in the formation of disulfide bonds and can be implicated in calcium responses. SelM may have a functional role in catalyzing free radicals and has been associated with Alzheimer's disease (AD). However, studies of SelM in chicken remain very limited. In this study, two groups of day-old broiler chicks (n = 40/group) were fed a corn-soy basal diet (BD, 13 μg Se/kg) and BD supplemented with Se (as sodium selenite) at 0.3 mg/kg. The brain was collected at 14, 21, 28, and 42 days of age. We performed a sequence analysis and predicted the structure and function of SelM. We also investigated the effects of Se deficiency on the expression of Selt, Selw, and Selm and the Se status in the chicken brain. The results show that Se deficiency induced the lower (P chicken, which might shed light on the role of SelM in human neurodegenerative disease. More studies are needed to confirm our conclusion. PMID:26315306

  10. Identification and comparisons of selenoproteins in rat brain and mouse neuroblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Zinn, K.; Chaudhuri, T.; Trokey, D.; Sunde, R.; O' Dell, B. (Univ. of Missouri, Columbia (United States))

    1991-03-11

    Male weanling rats, fed a Se-deficient torula-yeast diet or Se-adequate diet for 5 weeks, were injected with 400 {mu}Ci of {sup 75}Se as selenite, and sacrificed 2 and 4 wk after injection. Selenoproteins identified by SDS-PAGE included 6 major {sup 75}Se-peaks in cortex and cerebellum. While Se deficiency increased {sup 75}Se labeling of brain proteins, the percentages in each of the 6 peaks were unaffected by Se status. The total Se content of deficient cortex was only 5-10% less than adequate cortex, while deficient liver Se was 25-fold lower than adequate liver. The same 6 {sup 75}Se-peaks were identified in liver, with the 23-kDa peak greatly increased in Se adequate liver. When the 23-kDa peak was excluded, the relative distribution of {sup 75}Se in the remaining peaks was similar for liver, cortex, and cerebellum. Mouse neuroblastoma cells grown with {sup 75}Se-selenite showed labeling of 6 proteins of similar molecular weight as rat cortex, but {sup 75}Se distribution was different. Overall, the liver 23-kDa protein appeared to be the only {sup 75}Se-peak greatly changed as a result of Se status.

  11. Alterations in protein synthesis in the cyanobacterium Synechococcus sp. Strain PCC 6301 in response to Calendula Micrantha extract with the Molluscicidal activity

    International Nuclear Information System (INIS)

    The response to the extract of the egyptian wild herb Calendula Micrantha, with the Molluscicidal activity, was examined in the unicellular no bacterium Synechococcus sp. strain PCC 6301. growth and chlorophyll of the cells were only slightly affected by low plant extract concentrations but were drastically reduced by high concentration. the rate of protein synthesis progressively decreased by increasing extract concentration. the cells preferentially induced the synthesis of a limited number of polypeptides in response to the treatment. Among the induced polypeptides were those with apparent molecular weights of 161 K (161.000), 96.7 K, 93.4 K, 69.9 K, 59 K, 49 K, 45 K, 35 K, 32.4 K, 28 K, 24 K, 21.7 K, 18 K and 16 K based on their mobilities in gel electrophoresis. these initial studies suggest that the plant extract exerted certain stress which stimulated alteration in the pattern of protein synthesis in Synechococcus sp. some of induced polypeptides are similar to that known to occur in other stresses specially heat shock stress. 3 figs

  12. Association between Polymorphisms in Glutathione Peroxidase and Selenoprotein P Genes, Glutathione Peroxidase Activity, HRT Use and Breast Cancer Risk

    DEFF Research Database (Denmark)

    Méplan, Catherine; Dragsted, Lars Ove; Ravn-Haren, Gitte;

    2013-01-01

    975 controls matched for age and hormone replacement therapy (HRT) use was genotyped for five functional single nucleotide polymorphisms (SNPs) in SEPP1, GPX1, GPX4 and the antioxidant enzyme SOD2 genes. The influence of genetic polymorphisms on breast cancer risk was assessed using conditional......Breast cancer (BC) is one of the most common cancers in women. Evidence suggests that genetic variation in antioxidant enzymes could influence BC risk, but to date the relationship between selenoproteins and BC risk remains unclear. In this report, a study population including 975 Danish cases and...

  13. Determination of selenoprotein P in human plasma by solid phase extraction and inductively coupled plasma mass spectrometry

    DEFF Research Database (Denmark)

    Bendahl, L.; Sidenius, U.; Gammelgaard, Bente

    measured by inductively coupled plasma mass spectrometry (ICP-MS) monitoring the Se-82 isotope. Linear response was observed in the concentration range 0.3-70.8 mu g/l selenium as selenoprotein P with a correlation coefficient of 0.9994. The precision expressed as relative standard deviation was better...... than 2% in this range. The estimated limit of detection was 2 mu g/l and the experimentally verified quantification limit was 5 mu g/l, giving a relative standard deviation less than 2%. (C) 2000 Elsevier Science B.V. All rights reserved...

  14. Post ischemic reperfusion and anoxic perfusion in the isolated heart: alteration in distribution of radionuclides and in protein synthesis

    International Nuclear Information System (INIS)

    Reperfusion after ischemia and perfusion with total anoxia were studied in the isolated guinea pig heart model, Deprivation of oxygen in both situations resulted in a marked shift of circulation from the left to the right ventricle, with markedly increased spaces of distribution of sup(99m)Tc radionuclides and albumin in the latter. In view of the complexities of measuring protein synthesis during ischemia, continuous anoxic perfusion was used to evaluate this parameter in anoxic induced arrest. There was a profound fall in protein synthesis associated with this arrest, accompanied by a fall in ATP, creatine phosphate, glycogen, potassium, and a rise in lactate production. The fall in protein synthesis was more marked in the left ventricle. The changes in synthesis were almost completely prevented by initiating cardiac arrest with high K+ (16 meq/l) at the same time as anoxia; energy metabolism remained near normal, and recovery of contractility was nearly complete. The studies demonstrated the differences in vascular distribution between the ventricles after ischemia or with perfusion anoxia, the possible difference in availability of substrate to the two ventricles under these conditions, as well as the difference in protein synthetic response, and further support the protective effect of potassium induced arrest on the hypoxic heart

  15. Organ-Specific Alterations in Fatty Acid De Novo Synthesis and Desaturation in a Rat Model of Programmed Obesity

    Directory of Open Access Journals (Sweden)

    Desai Mina

    2011-05-01

    Full Text Available Abstract Background Small for gestational age (SGA leads to increased risk of adult obesity and metabolic syndrome. Offspring exposed to 50% maternal food restriction in utero are born smaller than Controls (FR, catch-up in growth by the end of the nursing period, and become obese adults. The objective of the study was to determine stearoyl-CoA desaturase activity (SCD1 and rates of de novo fatty acid synthesis in young FR and Control offspring tissues at the end of the nursing period, as possible contributors to catch-up growth. Methods From gestational day 10 to term, dams fed ad libitum (Control or were 50% food-restricted to produce small FR pups. Control dams nursed all pups. At postnatal day 1 (p1 and p21, offspring body tissues were analyzed by GC/MS, and desaturation indices of palmitoleate/palmitate and oleate/stearate were calculated. SCD1 gene expression was determined by real-time PCR on adipose and liver. Offspring were enriched with deuterium that was given to dams in drinking water during lactation and de novo synthesis of offspring body tissues was determined at p21. Primary adipocyte cell cultures were established at p21 and exposed to U13C-glucose. Results FR offspring exhibited higher desaturation index in p1 and p21 adipose tissue, but decreased desaturation index in liver at p21. SCD1 gene expression at p21 was correspondingly increased in adipose and decreased in liver. FR subcutaneous fat demonstrated increased de novo synthesis at p21. Primary cell cultures exhibited increased de novo synthesis in FR. Conclusions Adipose tissue is the first site to exhibit increased de novo synthesis and desaturase activity in FR. Therefore, abnormal lipogenesis is already present prior to onset of obesity during the period of catch-up growth. These abnormalities may contribute to future obesity development.

  16. Identification of a redox-modulatory interaction between selenoprotein W and 14-3-3 protein.

    Science.gov (United States)

    Jeon, Yeong Ha; Ko, Kwan Young; Lee, Jea Hwang; Park, Ki Jun; Jang, Jun Ki; Kim, Ick Young

    2016-01-01

    Selenoprotein W (SelW) contains a selenocysteine (Sec, U) in a conserved CXXU motif corresponding to the CXXC redox motif of thioredoxin, suggesting a putative redox function of SelW. We have previously reported that the binding of 14-3-3 protein to its target proteins, including CDC25B, Rictor and TAZ, is inhibited by the interaction of 14-3-3 protein with SelW. However, the binding mechanism is unclear. In this study, we sought to determine the binding site of SelW to understand the regulatory mechanism of the interaction between SelW and 14-3-3 and its biological effects. Phosphorylated Ser(pS) or Thr(pT) residues in RSXpSXP or RXXXp(S/T)XP motifs are well-known common 14-3-3-binding sites, but Thr41, Ser59, and T69 of SelW, which are computationally predicted to serve are phosphorylation sites, were neither phosphorylation sites nor sites involved in the interaction. A mutant SelW in which Sec13 is changed to Ser (U13S) was unable to interact with 14-3-3 protein and thus did not inhibit the interaction of 14-3-3 to other target proteins. However, other Cys mutants of SelW(C10S, C33S and C37S) normally interacted with 14-3-3 protein. The interaction of SelW to 14-3-3 protein was enhanced by diamide or H2O2 and decreased by dithiothreitol (DTT). Taken together, these findings demonstrate that the Sec of SelW is involved in its interaction with 14-3-3 protein and that this interaction is increased under oxidative stress conditions. Thus, SelW may have a regulatory function in redox cell signaling by interacting with 14-3-3 protein. PMID:26474786

  17. Selenoprotein P Inhibits Radiation-Induced Late Reactive Oxygen Species Accumulation and Normal Cell Injury

    Energy Technology Data Exchange (ETDEWEB)

    Eckers, Jaimee C.; Kalen, Amanda L.; Xiao, Wusheng; Sarsour, Ehab H.; Goswami, Prabhat C., E-mail: prabhat-goswami@uiowa.edu

    2013-11-01

    Purpose: Radiation is a common mode of cancer therapy whose outcome is often limited because of normal tissue toxicity. We have shown previously that the accumulation of radiation-induced late reactive oxygen species (ROS) precedes cell death, suggesting that metabolic oxidative stress could regulate cellular radiation response. The purpose of this study was to investigate whether selenoprotein P (SEPP1), a major supplier of selenium to tissues and an antioxidant, regulates late ROS accumulation and toxicity in irradiated normal human fibroblasts (NHFs). Methods and Materials: Flow cytometry analysis of cell viability, cell cycle phase distribution, and dihydroethidium oxidation, along with clonogenic assays, were used to measure oxidative stress and toxicity. Human antioxidant mechanisms array and quantitative real-time polymerase chain reaction assays were used to measure gene expression during late ROS accumulation in irradiated NHFs. Sodium selenite addition and SEPP1 overexpression were used to determine the causality of SEPP1 regulating late ROS accumulation and toxicity in irradiated NHFs. Results: Irradiated NHFs showed late ROS accumulation (4.5-fold increase from control; P<.05) that occurs after activation of the cell cycle checkpoint pathways and precedes cell death. The mRNA levels of CuZn- and Mn-superoxide dismutase, catalase, peroxiredoxin 3, and thioredoxin reductase 1 increased approximately 2- to 3-fold, whereas mRNA levels of cold shock domain containing E1 and SEPP1 increased more than 6-fold (P<.05). The addition of sodium selenite before the radiation treatment suppressed toxicity (45%; P<.05). SEPP1 overexpression suppressed radiation-induced late ROS accumulation (35%; P<.05) and protected NHFs from radiation-induced toxicity (58%; P<.05). Conclusion: SEPP1 mitigates radiation-induced late ROS accumulation and normal cell injury.

  18. Selenoprotein P in seminal fluid is a novel biomarker of sperm quality.

    Science.gov (United States)

    Michaelis, Marten; Gralla, Oliver; Behrends, Thomas; Scharpf, Marcus; Endermann, Tobias; Rijntjes, Eddy; Pietschmann, Nicole; Hollenbach, Birgit; Schomburg, Lutz

    2014-01-17

    Hepatically-derived selenoprotein P (SePP) transports selenium (Se) via blood to other tissues including the testes. Male Sepp-knockout mice are infertile. SePP-mediated Se transport to Sertoli cells is needed for supporting biosynthesis of the selenoenzyme glutathione peroxidase-4 (GPX4) in spermatozoa. GPX4 becomes a structural component of sperm midpiece during sperm maturation, and its expression correlates to semen quality. We tested whether SePP is also present in seminal plasma, potentially correlating to fertility parameters. Semen quality was assessed by sperm density, morphology and motility. SePP was measured by an immunoluminometric assay, and trace elements were determined by X-ray fluorescence spectroscopy. SePP levels were considerably lower in seminal plasma as compared to serum (0.4±0.1 mg/l vs. 3.5±1.0 mg/l); Se concentrations showed a similar but less pronounced difference (48.9±20.7 μg/l vs. 106.7±17.3 μg/l). Se and Zn correlated positively in seminal fluid but not in serum. Seminal plasma SePP concentrations were independent of serum SePP concentrations, but correlated positively to sperm density and fraction of vital sperm. SePP concentrations in seminal plasma of vasectomized men were similar to controls indicating that accessory sex glands are a testes-independent source of SePP. This notion was corroborated by histochemical analyses localizing SePP in epithelial cells of seminal vesicles. We conclude that SePP is not only involved in Se transport to testes supporting GPX4 biosynthesis but it also becomes secreted into seminal plasma, likely important to protect sperm during storage, genital tract passage and final journey. PMID:24361887

  19. Increased Selenoprotein P Levels in Subjects with Visceral Obesity and Nonalcoholic Fatty Liver Disease

    Directory of Open Access Journals (Sweden)

    Hae Yoon Choi

    2013-02-01

    Full Text Available BackgroundSelenoprotein P (SeP has recently been reported as a novel hepatokine that regulates insulin resistance and systemic energy metabolism in rodents and humans. We explored the associations among SeP, visceral obesity, and nonalcoholic fatty liver disease (NAFLD.MethodsWe examined serum SeP concentrations in subjects with increased visceral fat area (VFA or liver fat accumulation measured with computed tomography. Our study subjects included 120 nondiabetic individuals selected from participants of the Korean Sarcopenic Obesity Study. In addition, we evaluated the relationship between SeP and cardiometabolic risk factors, including homeostasis model of insulin resistance (HOMA-IR, high sensitivity C-reactive protein (hsCRP, adiponectin values, and brachial-ankle pulse wave velocity (baPWV.ResultsSubjects with NAFLD showed increased levels of HOMA-IR, hsCRP, VFA, and several components of metabolic syndrome and decreased levels of adiponectin and high density lipoprotein cholesterol than those of controls. Serum SeP levels were positively correlated with VFA, hsCRP, and baPWV and negatively correlated with the liver attenuation index. Not only subjects with visceral obesity but also those with NAFLD exhibited significantly increased SeP levels (P<0.001. In multiple logistic regression analysis, the subjects in the highest SeP tertile showed a higher risk for NAFLD than those in the lowest SeP tertile, even after adjusting for potential confounding factors (odds ratio, 7.48; 95% confidence interval, 1.72 to 32.60; P=0.007.ConclusionCirculating SeP levels were increased in subjects with NAFLD as well as in those with visceral obesity and may be a novel biomarker for NAFLD.

  20. Direct Interaction of Selenoprotein R with Clusterin and Its Possible Role in Alzheimer's Disease.

    Science.gov (United States)

    Chen, Ping; Wang, Chao; Ma, Xiaojie; Zhang, Yizhe; Liu, Qing; Qiu, Shi; Liu, Qiong; Tian, Jing; Ni, Jiazuan

    2013-01-01

    Selenoprotein R (SelR) plays an important role in maintaining intracellular redox balance by reducing the R-form of methionine sulfoxide to methionine. As SelR is highly expressed in brain and closely related to Alzheimer's disease (AD), its biological functions in human brain become a research focus. In this paper, the selenocysteine-coding TGA of SelR gene was mutated to cysteine-coding TGC and used to screen the human fetal brain cDNA library with a yeast two-hybrid system. Our results demonstrated that SelR interacts with clusterin (Clu), a chaperone protein. This protein interaction was further verified by fluorescence resonance energy transfer (FRET), coimmunoprecipitation (co-IP), and pull-down assays. The interacting domain of Clu was determined by co-IP to be a dynamic, molten globule structure spanning amino acids 315 to 381 with an amphipathic-helix. The interacting domain of SelR was investigated by gene manipulation, ligand replacement, protein over-expression, and enzyme activity measurement to be a tetrahedral complex consisting of a zinc ion binding with four Cys residues. Study on the mutual effect of SelR and Clu showed synergic property between the two proteins. Cell transfection with SelR gene increased the expression of Clu, while cell transfection with Clu promoted the enzyme activity of SelR. Co-overexpression of SelR and Clu in N2aSW cells, an AD model cell line, significantly decreased the level of intracellular reactive oxygen species. Furthermore, FRET and co-IP assays demonstrated that Clu interacted with β-amyloid peptide, a pathological protein of AD, which suggested a potential effect of SelR and Aβ with the aid of Clu. The interaction between SelR and Clu provides a novel avenue for further study on the mechanism of SelR in AD prevention. PMID:23805218

  1. Direct Interaction of Selenoprotein R with Clusterin and Its Possible Role in Alzheimer's Disease.

    Directory of Open Access Journals (Sweden)

    Ping Chen

    Full Text Available Selenoprotein R (SelR plays an important role in maintaining intracellular redox balance by reducing the R-form of methionine sulfoxide to methionine. As SelR is highly expressed in brain and closely related to Alzheimer's disease (AD, its biological functions in human brain become a research focus. In this paper, the selenocysteine-coding TGA of SelR gene was mutated to cysteine-coding TGC and used to screen the human fetal brain cDNA library with a yeast two-hybrid system. Our results demonstrated that SelR interacts with clusterin (Clu, a chaperone protein. This protein interaction was further verified by fluorescence resonance energy transfer (FRET, coimmunoprecipitation (co-IP, and pull-down assays. The interacting domain of Clu was determined by co-IP to be a dynamic, molten globule structure spanning amino acids 315 to 381 with an amphipathic-helix. The interacting domain of SelR was investigated by gene manipulation, ligand replacement, protein over-expression, and enzyme activity measurement to be a tetrahedral complex consisting of a zinc ion binding with four Cys residues. Study on the mutual effect of SelR and Clu showed synergic property between the two proteins. Cell transfection with SelR gene increased the expression of Clu, while cell transfection with Clu promoted the enzyme activity of SelR. Co-overexpression of SelR and Clu in N2aSW cells, an AD model cell line, significantly decreased the level of intracellular reactive oxygen species. Furthermore, FRET and co-IP assays demonstrated that Clu interacted with β-amyloid peptide, a pathological protein of AD, which suggested a potential effect of SelR and Aβ with the aid of Clu. The interaction between SelR and Clu provides a novel avenue for further study on the mechanism of SelR in AD prevention.

  2. Selenoprotein W depletion induces a p53- and p21-dependent delay in cell cycle progression in RWPE-1 prostate epithelial cells

    Science.gov (United States)

    The anticancer activity of selenium (Se) has been demonstrated in myriad animal and in vitro studies, yet the mechanisms remain obscure. The relative importance of small selenium compounds versus selenoproteins in the cancer-protective activity of Se is unresolved, but the main form of Se in animal ...

  3. S-Adenosylmethionine-dependent protein methylation Is required for expression of selenoprotein P and gluconeogenic enzymes in HepG2 human hepatocytes

    Science.gov (United States)

    Cellular methylation processes enable expression of gluconeogenic enzymes and metabolism of the nutrient selenium (Se). Se status may relate to type-II diabetes and plasma levels of selenoprotein P (SEPP1) are positively correlated with insulin resistance. Increased expression of gluconeogenic enzym...

  4. Can current moisture responses predict soil CO2 efflux under altered precipitation regimes? A synthesis of manipulation experiments

    DEFF Research Database (Denmark)

    Vicca, S.; Bahn, M.; Estiarte, M.;

    2014-01-01

    dependencies of SCE. Hence, the most justified answer to the question of whether current moisture responses of SCE can be extrapolated to predict SCE under altered precipitation regimes is 'no' - as based on the most reliable data sets available. We strongly recommend that future experiments focus more...

  5. Short communication: Altered expression of specificity protein 1 impairs milk fat synthesis in goat mammary epithelial cells.

    Science.gov (United States)

    Zhu, J J; Luo, J; Xu, H F; Wang, H; Loor, J J

    2016-06-01

    Specificity protein 1 (encoded by SP1) is a novel transcription factor important for the regulation of lipid metabolism and the normal function of various hormones in model organisms. Its potential role, if any, on ruminant milk fat is unknown. Despite the lower expression of the lipolysis-related gene ATGL (by 44 and 37% respectively), both the adenoviral overexpression and the silencing of SP1 [via short interfering (si)RNA] markedly reduced cellular triacylglycerol (TAG) content (by 28 and 25%, respectively), at least in part by decreasing the expression of DGAT1 (-36% in adenovirus treatment) and DGAT2 (-81 and -87%, respectively) that are involved in TAG synthesis. Consistent with the markedly lower expression of genes related to lipid droplet formation and secretion (TIP47 by 19 and 32%, and ADFP by 25 and 25%, respectively), cellular lipid droplet content was also decreased sharply, by 9 and 8.5%, respectively, after adenoviral overexpression of SP1 or its silencing via siRNA. Overall, the results underscored a potentially important role of SP1 in maintaining milk-fat droplet synthesis in goat mammary epithelial cells. PMID:26995134

  6. Different Forms of Selenoprotein M Differentially Affect Aβ Aggregation and ROS Generation

    Directory of Open Access Journals (Sweden)

    Ping Chen

    2013-02-01

    Full Text Available Selenoprotein M (SelM, one of the executants of selenium in vivo, is highly expressed in human brain and most probably involved in antioxidation, neuroprotection, and intracellular calcium regulation, which are the key factors for preventing the onset and progression of Alzheimer’s disease (AD. In this paper, human SelM was successfully overexpressed in human embryonic kidney cells HEK293T. Sodium selenite (Na2SeO3 0.5 μmol/L increased the expression of full-length SelM and inhibited the expression of truncated SelM. The full-length SelM exhibited higher antioxidant activity than its selenocysteine-to-cysteine mutation form SelM', whereas the truncated SelM had an adverse effect that increased the oxidative stress level of cells. When β-amyloid (Aβ42, an AD relevant peptide was cotransfected with the empty expression vector, SelM, or SelM' under the induction of 0.5 μmol/L Na2SeO3, the intracellular Aβ42 aggregation rates were detected to be 57.9% ± 5.5%, or 22.3% ± 2.6%, or 26.3% ± 2.1%, respectively, showing the inhibitory effects on Aβ aggregation by the full-length SelM and SelM'. Meanwhile, the intumescentia of mitochondria caused by Aβ42 transfection was significantly mitigated by the cotransfection of SelM or SelM′ with Aβ42 under the induction of 0.5 μmol/L Na2SeO3. On the contrary, cotransfection of SelM and Aβ42 without the induction of Na2SeO3 increased Aβ42 aggregation rate to 65.1% ± 3.2%, and it could not inhibit the Aβ-induced intumescent mitochondria. In conclusion, full-length SelM and SelM¢ might prevent Aβ aggregation by resisting oxidative stress generated during the formation of Aβ oligomers in cells.

  7. Alternative transcripts and 3'UTR elements govern the incorporation of selenocysteine into selenoprotein S.

    Directory of Open Access Journals (Sweden)

    Jodi L Bubenik

    Full Text Available Selenoprotein S (SelS is a 189 amino acid trans-membrane protein that plays an important yet undefined role in the unfolded protein response. It has been proposed that SelS may function as a reductase, with the penultimate selenocysteine (Sec(188 residue participating in a selenosulfide bond with cysteine (Cys(174. Cotranslational incorporation of Sec into SelS depends on the recoding of the UGA codon, which requires a Selenocysteine Insertion Sequence (SECIS element in the 3'UTR of the transcript. Here we identify multiple mechanisms that regulate the expression of SelS. The human SelS gene encodes two transcripts (variants 1 and 2, which differ in their 3'UTR sequences due to an alternative splicing event that removes the SECIS element from the variant 1 transcript. Both transcripts are widely expressed in human cell lines, with the SECIS-containing variant 2 mRNA being more abundant. In vitro experiments demonstrate that the variant 1 3'UTR does not allow readthrough of the UGA/Sec codon. Thus, this transcript would produce a truncated protein that does not contain Sec and cannot make the selenosulfide bond. While the variant 2 3'UTR does support Sec insertion, its activity is weak. Bioinformatic analysis revealed two highly conserved stem-loop structures, one in the proximal part of the variant 2 3'UTR and the other immediately downstream of the SECIS element. The proximal stem-loop promotes Sec insertion in the native context but not when positioned far from the UGA/Sec codon in a heterologous mRNA. In contrast, the 140 nucleotides downstream of the SECIS element inhibit Sec insertion. We also show that endogenous SelS is enriched at perinuclear speckles, in addition to its known localization in the endoplasmic reticulum. Our results suggest the expression of endogenous SelS is more complex than previously appreciated, which has implications for past and future studies on the function of this protein.

  8. Selenoprotein Transcript Level and Enzyme Activity as Biomarkers for Selenium Status and Selenium Requirements of Chickens (Gallus gallus)

    Science.gov (United States)

    Li, Jin-Long; Sunde, Roger A.

    2016-01-01

    The NRC selenium (Se) requirement for broiler chicks is 0.15 μg Se/g diet, based primarily on weight gain and feed intake studies reported in 1986. To determine Se requirements in today’s rapidly growing broiler chick, day-old male chicks were fed Se-deficient basal diets supplemented with graded levels of Se (0, 0.025, 0.05, 0.075, 0.1, 0.2, 0.3, 0.5, 0.75, and 1.0 μg Se/g) as Na2SeO3 (5/treatment). Diets contained 15X the vitamin E requirement, and there were no gross signs of Se-deficiency. At 29 d, Se-deficient chicks weighed 62% of Se-supplemented chicks; 0.025 μg Se/g reversed this effect, indicating a minimum Se requirement of 0.025 μg Se/g diet for growth for male broiler chicks. Enzyme activities in Se-deficient chicks for plasma GPX3, liver and gizzard GPX1, and liver and gizzard GPX4 decreased dramatically to 3, 2, 5, 10 and 5%, respectively, of Se-adequate levels, with minimum Se requirements of 0.10–0.13 μg Se/g, and with defined plateaus above these levels. Pancreas GPX1 and GPX4 activities, however, lacked defined plateaus, with breakpoints at 0.3 μg Se/g. qPCR measurement of all 24 chicken selenoprotein transcripts, plus SEPHS1, found that SEPP1 in liver, GPX3 in gizzard, and SEPP1, GPX3 and SELK in pancreas were expressed at levels comparable to housekeeping transcripts. Only 33%, 25% and 50% of selenoprotein transcripts were down-regulated significantly by Se deficiency in liver, gizzard and pancreas, respectively. No transcripts could be used as biomarkers for supernutritional Se status. For export selenoproteins SEPP1 and GPX3, tissue distribution, high expression and Se-regulation clearly indicate unique Se metabolism, which may underlie tissues targeted by Se deficiency. Based on enzyme activities in liver, gizzard, and plasma, the minimum Se requirement in today’s broiler chick is 0.15 μg Se/g diet; pancreas data indicate that the Se requirement should be raised to 0.2 μg Se/g diet to provide a margin of safety. PMID:27045754

  9. Selenoprotein Transcript Level and Enzyme Activity as Biomarkers for Selenium Status and Selenium Requirements in the Turkey (Meleagris gallopavo)

    Science.gov (United States)

    Taylor, Rachel M.; Sunde, Roger A.

    2016-01-01

    The current National Research Council (NRC) selenium (Se) requirement for the turkey is 0.2 μg Se/g diet. The sequencing of the turkey selenoproteome offers additional molecular biomarkers for assessment of Se status. To determine dietary Se requirements using selenoprotein transcript levels and enzyme activities, day-old male turkey poults were fed a Se-deficient diet supplemented with graded levels of Se (0, 0.025, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.75, 1.0 μg Se/g diet) as selenite, and 12.5X the vitamin E requirement. Poults fed less than 0.05 μg Se/g diet had a significantly reduced rate of growth, indicating the Se requirement for growth in young male poults is 0.05 μg Se/g diet. Se deficiency decreased plasma GPX3 (glutathione peroxidase), liver GPX1, and liver GPX4 activities to 2, 3, and 7%, respectively, of Se-adequate levels. Increasing Se supplementation resulted in well-defined plateaus for all blood, liver and gizzard enzyme activities and mRNA levels, showing that these selenoprotein biomarkers could not be used as biomarkers for supernutritional-Se status. Using selenoenzyme activity, minimum Se requirements based on red blood cell GPX1, plasma GPX3, and pancreas and liver GPX1 activities were 0.29–0.33 μg Se/g diet. qPCR analyses using all 10 dietary Se treatments for all 24 selenoprotein transcripts (plus SEPHS1) in liver, gizzard, and pancreas found that only 4, 4, and 3 transcripts, respectively, were significantly down-regulated by Se deficiency and could be used as Se biomarkers. Only GPX3 and SELH mRNA were down regulated in all 3 tissues. For these transcripts, minimum Se requirements were 0.07–0.09 μg Se/g for liver, 0.06–0.15 μg Se/g for gizzard, and 0.13–0.18 μg Se/g for pancreas, all less than enzyme-based requirements. Panels based on multiple Se-regulated transcripts were effective in identifying Se deficiency. These results show that the NRC turkey dietary Se requirement should be raised to 0.3 μg Se/g diet. PMID

  10. Selenoprotein Transcript Level and Enzyme Activity as Biomarkers for Selenium Status and Selenium Requirements of Chickens (Gallus gallus).

    Science.gov (United States)

    Li, Jin-Long; Sunde, Roger A

    2016-01-01

    The NRC selenium (Se) requirement for broiler chicks is 0.15 μg Se/g diet, based primarily on weight gain and feed intake studies reported in 1986. To determine Se requirements in today's rapidly growing broiler chick, day-old male chicks were fed Se-deficient basal diets supplemented with graded levels of Se (0, 0.025, 0.05, 0.075, 0.1, 0.2, 0.3, 0.5, 0.75, and 1.0 μg Se/g) as Na2SeO3 (5/treatment). Diets contained 15X the vitamin E requirement, and there were no gross signs of Se-deficiency. At 29 d, Se-deficient chicks weighed 62% of Se-supplemented chicks; 0.025 μg Se/g reversed this effect, indicating a minimum Se requirement of 0.025 μg Se/g diet for growth for male broiler chicks. Enzyme activities in Se-deficient chicks for plasma GPX3, liver and gizzard GPX1, and liver and gizzard GPX4 decreased dramatically to 3, 2, 5, 10 and 5%, respectively, of Se-adequate levels, with minimum Se requirements of 0.10-0.13 μg Se/g, and with defined plateaus above these levels. Pancreas GPX1 and GPX4 activities, however, lacked defined plateaus, with breakpoints at 0.3 μg Se/g. qPCR measurement of all 24 chicken selenoprotein transcripts, plus SEPHS1, found that SEPP1 in liver, GPX3 in gizzard, and SEPP1, GPX3 and SELK in pancreas were expressed at levels comparable to housekeeping transcripts. Only 33%, 25% and 50% of selenoprotein transcripts were down-regulated significantly by Se deficiency in liver, gizzard and pancreas, respectively. No transcripts could be used as biomarkers for supernutritional Se status. For export selenoproteins SEPP1 and GPX3, tissue distribution, high expression and Se-regulation clearly indicate unique Se metabolism, which may underlie tissues targeted by Se deficiency. Based on enzyme activities in liver, gizzard, and plasma, the minimum Se requirement in today's broiler chick is 0.15 μg Se/g diet; pancreas data indicate that the Se requirement should be raised to 0.2 μg Se/g diet to provide a margin of safety. PMID:27045754

  11. Can current moisture responses predict soil CO2 efflux under altered precipitation regimes? A synthesis of manipulation experiments

    Directory of Open Access Journals (Sweden)

    S. Vicca

    2014-01-01

    Full Text Available As a key component of the carbon cycle, soil CO2 efflux (SCE is being increasingly studied to improve our mechanistic understanding of this important carbon flux. Predicting ecosystem responses to climate change often depends on extrapolation of current relationships between ecosystem processes and their climatic drivers to conditions not yet experienced by the ecosystem. This raises the question to what extent these relationships remain unaltered beyond the current climatic window for which observations are available to constrain the relationships. Here, we evaluate whether current responses of SCE to fluctuations in soil temperature and soil water content can be used to predict SCE under altered rainfall patterns. Of the 58 experiments for which we gathered SCE data, 20 were discarded because either too few data were available, or inconsistencies precluded their incorporation in the analyses. The 38 remaining experiments were used to test the hypothesis that a model parameterized with data from the control plots (using soil temperature and water content as predictor variables could adequately predict SCE measured in the manipulated treatment. Only for seven of these 38 experiments, this hypothesis was rejected. Importantly, these were the experiments with the most reliable datasets, i.e., those providing high-frequency measurements of SCE. Accordingly, regression tree analysis demonstrated that measurement frequency was crucial; our hypothesis could be rejected only for experiments with measurement intervals of less than 11 days, and was not rejected for any of the 24 experiments with larger measurement intervals. This highlights the importance of high-frequency measurements when studying effects of altered precipitation on SCE, probably because infrequent measurement schemes have insufficient capacity to detect shifts in the climate-dependencies of SCE. We strongly recommend that future experiments focus more strongly on establishing response

  12. Can current moisture responses predict soil CO2 efflux under altered precipitation regimes? A synthesis of manipulation experiments

    DEFF Research Database (Denmark)

    Vicca, S.; Bahn, M.; Estiarte, M.;

    2014-01-01

    responses of SCE to fluctuations in soil temperature and soil water content can be used to predict SCE under altered rainfall patterns. Of the 58 experiments for which we gathered SCE data, 20 were discarded because either too few data were available or inconsistencies precluded their incorporation in the...... analyses. The 38 remaining experiments were used to test the hypothesis that a model parameterized with data from the control plots (using soil temperature and water content as predictor variables) could adequately predict SCE measured in the manipulated treatment. Only for 7 of these 38 experiments was...... more strongly on establishing response functions across a broader range of precipitation regimes and soil moisture conditions. Such experiments should make accurate measurements of water availability, should conduct high-frequency SCE measurements, and should consider both instantaneous responses and...

  13. Cellular proliferation and infiltration following interstitial irradiation of normal dog brain is altered by an inhibitor of polyamine synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Fike, J.R.; Gobbel, G.T.; Chou, D. [Univ. of California, San Francisco, CA (United States)] [and others

    1995-07-15

    The objectives of this study were to quantitatively define proliferative and infiltrative cell responses after focal {sup 125}I irradiation of normal brain, and to determine the effects of an intravenous infusion of {alpha}-defluoromethylornithine (DFMO) on those responses. Adult beagle dogs were irradiated using high activity {sup 125}I sources. Cellular responses were quantified using a histomorphometric analysis. After radiation alone, cellular events included a substantial acute inflammatory response followed by increased BrdU labeling and progressive increases in numbers of capillaries and astrocytes. {alpha}-Difluoromethylornithine treatment significantly affected the measured cell responses. As in controls, an early inflammatory response was measured, but after 2 weeks there were more PMNs/unit area than in controls. The onset of measurable BrdU labeling was delayed in DFMO-treated animals, and the magnitude of labeling was significantly reduced. Increases in astrocyte and vessel numbers/mm{sup 2} were observed after a 2-week delay. At the site of implant, astrocytes from DFMO-treated dogs were significantly smaller than those from controls. There is substantial cell proliferation and infiltration in response to interstitial irradiation of normal brain, and these responses are significantly altered by DFMO treatment. Although the precise mechanisms by which DFMO exerts its effects in this model are not known, the results from this study suggest that modification of radiation injury may be possible by manipulating the response of normal cells to injury. 57 refs., 6 figs.

  14. Designed synthesis and chiroptical properties of regioregular poly(p-phenyleneethynylene-alter-m-phenyleneethynylene) bearing (-)-trans-rnyrtanoxyl side groups

    Institute of Scientific and Technical Information of China (English)

    Xiangfeng LI; Chusheng LI; Jiang LU; Hui LIANG

    2009-01-01

    Two regioregular poly(p-phenyleneethyny-lene-alter-m-phenyleneethynylene)s bearing (-)-trans-myrtanoxyl side groups with different substitution patterns were designed and synthesized, e.g. Myr-PMPE-1 and Myr-PMPE-2. In Myr-PMPE-1, the side chiral groups are distributed uniformly along the backbone. In Myr-PMPE-2, the distribution of the side chiral groups is alternatively crowded and loose. Both of these two polymers show no CD signal in solutions because of their good solubility. The investigations of chiroptical properties of these two polymers were carried out in the form of spin-coated films. The films were annealed above the glass temperature of the corresponding polymer, and the effects of annealing temperature and time on the properties of the films were investigated by UV-Vis absorption, fluorescence and circular dichroism spectra. The results show that annealing treatment had no significant effect on the properties of Myr-PMPE-1, including UV-Vis absorption, fluorescence and optical activity. The maximum absolute value of dissymmetry factor (|gmax|) was 1.62 × 10-4. On the other hand, annealing treatment significantly affected the proper-ties of Myr-PMPE-2. Without annealing or being annealed below 100℃, Myr-PMPE-2 films show almost no Cotton effect. In contrast, when annealed above 120℃, the absorption and emission of Myr-PMPE-2 films slightly red shifted with increasing annealing temperature and annealing time. Most importantly, the intensity of CD signals increased significantly and the optical activity of Myr-PMPE-2 films markedly increased. After annealing at 140℃ for 4h, the |gmax| of Myr-PMPE-2 films was increased up to 3.07 x 10 3, about one order of magnitude higher than that of Myr-PMPE-1 films.

  15. Cellular proliferation and infiltration following interstitial irradiation of normal dog brain is altered by an inhibitor of polyamine synthesis

    International Nuclear Information System (INIS)

    Purpose: The objectives of this study were to quantitatively define proliferative and infiltrative cell responses after focal 125I irradiation of normal brain, and to determine the effects of an intravenous infusion of α-difluoromethylornithine (DFMO) on those responses. Methods and Materials: Adult beagle dogs were irradiated using high activity 125I sources. Saline (control) or DFMO (150 mg/kg/day) was infused for 18 days starting 2 days before irradiation. At varying times up to 8 weeks after irradiation, brain tissues were collected and the cell responses in and around the focal lesion were quantified. Immunohistochemical stains were used to label astrocytes (GFAP), vascular endothelial cells (Factor VIII), polymorphonuclear leukocytes (PMNs; MAC 387) and cells synthesizing deoxyribonucleic acid (DNA) (BrdU). Cellular responses were quantified using a histomorphometric analysis. Results: After radiation alone, cellular events included a substantial acute inflammatory response followed by increased BrdU labeling and progressive increases in numbers of capillaries and astrocytes. α-Difluoromethylornithine treatment significantly affected the measured cell responses. As in controls, an early inflammatory response was measured, but after 2 weeks there were more PMNs/unit area than in controls. The onset of measurable BrdU labeling was delayed in DFMO-treated animals, and the magnitude of labeling was significantly reduced. Increases in astrocyte and vessel numbers/mm2 were observed after a 2-week delay. At the site of implant, astrocytes from DFMO-treated dogs were significantly smaller than those from controls. Conclusions: There is substantial cell proliferation and infiltration in response to interstitial irradiation of normal brain, and these responses are significantly altered by DFMO treatment. Although the precise mechanisms by which DFMO exerts its effects in this model are not known, the results from this study suggest that modification of radiation

  16. Selenoprotein S (SEPS1) gene -105G>A promoter polymorphism influences the susceptibility to gastric cancer in the Japanese population

    OpenAIRE

    Nagasaka Mitsuo; Nakamura Masakatsu; Kamiya Yoshio; Fujita Hiroshi; Maruyama Naoko; Yoshioka Daisuke; Ohkubo Masaaki; Tahara Tomomitsu; Arisawa Tomiyasu; Shibata Tomoyuki; Iwata Masami; Takahama Kazuya; Watanabe Makoto; Hirata Ichiro

    2009-01-01

    Abstract Background Inflammation is a key factor in the process of carcinogenesis from chronic gastritis induced by Helicobacter pylori. Selenoprotein S (SEPS1) is involved in the control of the inflammatory response in the endoplasmic reticulum (ER). Recently the -105G>A polymorphism in the promoter of SEPS1 was shown to increase pro-inflammatory cytokine expression. We examined the association between this polymorphism and the risk of gastric cancer. Methods We took stomach biopsies during ...

  17. Prenatal Exposure of Cypermethrin Induces Similar Alterations in Xenobiotic-Metabolizing Cytochrome P450s and Rate-Limiting Enzymes of Neurotransmitter Synthesis in Brain Regions of Rat Offsprings During Postnatal Development.

    Science.gov (United States)

    Singh, Anshuman; Mudawal, Anubha; Maurya, Pratibha; Jain, Rajeev; Nair, Saumya; Shukla, Rajendra K; Yadav, Sanjay; Singh, Dhirendra; Khanna, Vinay Kumar; Chaturvedi, Rajnish Kumar; Mudiam, Mohana K R; Sethumadhavan, Rao; Siddiqi, Mohammad Imran; Parmar, Devendra

    2016-08-01

    Oral administration of low doses of cypermethrin to pregnant Wistar rats led to a dose-dependent differences in the induction of xenobiotic-metabolizing cytochrome P450s (CYPs) messenger RNA (mRNA) and protein in brain regions isolated from the offsprings postnatally at 3 weeks that persisted up to adulthood. Similar alterations were observed in the expression of rate-limiting enzymes of neurotransmitter synthesis in brain regions of rat offsprings. These persistent changes were associated with alterations in circulating levels of growth hormone (GH), cognitive functions, and accumulation of cypermethrin and its metabolites in brain regions of exposed offsprings. Though molecular docking studies failed to identify similarities between the docked conformations of cypermethrin with CYPs and neurotransmitter receptors, in silico analysis identified regulatory sequences of CYPs in the promoter region of rate-limiting enzymes of neurotransmitter synthesis. Further, rechallenge of the prenatally exposed offsprings at adulthood with cypermethrin (p.o. 10 mg/kg × 6 days) led to a greater magnitude of alterations in the expression of CYPs and rate-limiting enzymes of neurotransmitter synthesis in different brain regions. These alterations were associated with a greater magnitude of decrease in the circulating levels of GH and cognitive functions in rechallenged offsprings. Our data has led us to suggest that due to the immaturity of CYPs in fetus or during early development, even the low-level exposure of cypermethrin may be sufficient to interact with the CYPs, which in turn affect the neurotransmission processes and may help in explaining the developmental neurotoxicity of cypermethrin. PMID:26115703

  18. The Timing of Multiple Retrieval Events Can Alter GluR1 Phosphorylation and the Requirement for Protein Synthesis in Fear Memory Reconsolidation

    Science.gov (United States)

    Jarome, Timothy J.; Kwapis, Janine L.; Werner, Craig T.; Parsons, Ryan G.; Gafford, Georgette M.; Helmstetter, Fred J.

    2012-01-01

    Numerous studies have indicated that maintaining a fear memory after retrieval requires de novo protein synthesis. However, no study to date has examined how the temporal dynamics of repeated retrieval events affect this protein synthesis requirement. The present study varied the timing of a second retrieval of an established auditory fear memory…

  19. Cellular Selenoprotein mRNA Tethering via Antisense Interactions with Ebola and HIV-1 mRNAs May Impact Host Selenium Biochemistry.

    Science.gov (United States)

    Taylor, Ethan Will; Ruzicka, Jan A; Premadasa, Lakmini; Zhao, Lijun

    2016-01-01

    Regulation of protein expression by non-coding RNAs typically involves effects on mRNA degradation and/or ribosomal translation. The possibility of virus-host mRNA-mRNA antisense tethering interactions (ATI) as a gain-of-function strategy, via the capture of functional RNA motifs, has not been hitherto considered. We present evidence that ATIs may be exploited by certain RNA viruses in order to tether the mRNAs of host selenoproteins, potentially exploiting the proximity of a captured host selenocysteine insertion sequence (SECIS) element to enable the expression of virally-encoded selenoprotein modules, via translation of in-frame UGA stop codons as selenocysteine. Computational analysis predicts thermodynamically stable ATIs between several widely expressed mammalian selenoprotein mRNAs (e.g., isoforms of thioredoxin reductase) and specific Ebola virus mRNAs, and HIV-1 mRNA, which we demonstrate via DNA gel shift assays. The probable functional significance of these ATIs is further supported by the observation that, in both viruses, they are located in close proximity to highly conserved in-frame UGA stop codons at the 3' end of open reading frames that encode essential viral proteins (the HIV-1 nef protein and the Ebola nucleoprotein). Significantly, in HIV/AIDS patients, an inverse correlation between serum selenium and mortality has been repeatedly documented, and clinical benefits of selenium in the context of multi-micronutrient supplementation have been demonstrated in several well-controlled clinical trials. Hence, in the light of our findings, the possibility of a similar role for selenium in Ebola pathogenesis and treatment merits serious investigation. PMID:26369818

  20. Cellular Selenoprotein mRNA Tethering via Antisense Interactions with Ebola and HIV-1 mRNAs May Impact Host Selenium Biochemistry

    Science.gov (United States)

    Taylor, Ethan Will; Ruzicka, Jan A.; Premadasa, Lakmini; Zhao, Lijun

    2016-01-01

    Regulation of protein expression by non-coding RNAs typically involves effects on mRNA degradation and/or ribosomal translation. The possibility of virus-host mRNA-mRNA antisense tethering interactions (ATI) as a gain-of-function strategy, via the capture of functional RNA motifs, has not been hitherto considered. We present evidence that ATIs may be exploited by certain RNA viruses in order to tether the mRNAs of host selenoproteins, potentially exploiting the proximity of a captured host selenocysteine insertion sequence (SECIS) element to enable the expression of virally-encoded selenoprotein modules, via translation of in-frame UGA stop codons as selenocysteine. Computational analysis predicts thermodynamically stable ATIs between several widely expressed mammalian selenoprotein mRNAs (e.g., isoforms of thioredoxin reductase) and specific Ebola virus mRNAs, and HIV-1 mRNA, which we demonstrate via DNA gel shift assays. The probable functional significance of these ATIs is further supported by the observation that, in both viruses, they are located in close proximity to highly conserved in-frame UGA stop codons at the 3′ end of open reading frames that encode essential viral proteins (the HIV-1 nef protein and the Ebola nucleoprotein). Significantly, in HIV/AIDS patients, an inverse correlation between serum selenium and mortality has been repeatedly documented, and clinical benefits of selenium in the context of multi-micronutrient supplementation have been demonstrated in several well-controlled clinical trials. Hence, in the light of our findings, the possibility of a similar role for selenium in Ebola pathogenesis and treatment merits serious investigation. PMID:26369818

  1. 鸡硒蛋白T的硒代半胱氨酸插入序列元件、蛋白结构与功能及组织表达差异%Analysis of selenocysteine insertion sequence element, structures and functions and expression profiles of selenoprotein T in chicken

    Institute of Scientific and Technical Information of China (English)

    葛延松; 曹嫦妤; 王丽丽; 李楠; 江秀清; 李金龙

    2014-01-01

    also been showed in alter cell adhesion . Up to now , 25 selenoprotein-encoding genes were identified in birds , however , only about half have been functionally characterized , most of which were involved in redox reactions . SelT was a Se-containing protein whose cellular function has not been characterized . Research on the structure and function of SelT was still in its infancy , but reports in mammals about SelT and the information about avian SelT were not clear . The purpose of this study is to explore the selenocysteine insertion sequence ( SECIS) element , structures and functions of chicken SelT and the expression profiles of SelT in chicken tissues . The chicken SelT sequence was used in the experiment . The SECIS elements of 12 vertebrates were analyzed by the SECISearch 2.19 . The homologies of the molecule nucleotide and amino acid sequences on vertebrates were analyzed by DNAStar . The structure and functions of chicken SelT were predicted with the bioinformatics . The distribution of SelT in 30 tissues of 35-day-old chicken was analyzed by fluorescent quantitative real-time PCR ( qRT-PCR) . The results showed that SECIS element of vertebrates belonged to the type Ⅱ SECIS element . Compared with chicken and other 11 vertebrates , the nucleotide sequence homologies of SelT were 48.0% 85.1% . The homologies of amino acid sequences of chicken SelT with Xenopus laevis or Danio rerio were less than 90.0% and with other nine kinds of animals were among 90.6% 94.9% . The chicken SelT was a transmembrane protein and had a signal peptide . It belonged to the RDx families and its enzyme classification was EC 2.5.1.18 . SelT had binding sites with Ca2+ . The results of fqRT-PCR showed that the SelT was widely expressed in chicken tissues , and the expression level in testis was the highest . In summary , the SECIS element of vertebrate SelT belongs to the type Ⅱ and SelT is highly conserved in vertebrates . Avian SelT contains a CxxU motif in a thioredoxin

  2. Sepp1UF forms are N-terminal selenoprotein P truncations that have peroxidase activity when coupled with thioredoxin reductase-1

    OpenAIRE

    Kurokawa, Suguru; Eriksson, Sofi; Rose, Kristie L.; Wu, Sen; Motley, Amy K.; Hill, Salisha; Winfrey, Virginia P.; McDonald, W. Hayes; Capecchi, Mario R.; Atkins, John F; Arnér, Elias S. J.; Hill, Kristina E.; Raymond F Burk

    2014-01-01

    Mouse selenoprotein P (Sepp1) consists of an N-terminal domain (residues 1-239) that contains 1 selenocysteine (U) as residue 40 in a proposed redox-active motif (-UYLC-) and a C-terminal domain (residues 240-361) that contains 9 selenocysteines. Sepp1 transports selenium from the liver to other tissues by receptor-mediated endocytosis. It also reduces oxidative stress in vivo by an unknown mechanism. A previously uncharacterized plasma form of Sepp1 is filtered in the glomerulus and taken up...

  3. Delayed cell cycle progression in selenoprotein W depleted cells is regulated by a mitogen-activated protein kinase kinase 4–p38–p53 pathway

    Science.gov (United States)

    Selenoprotein W (SEPW1) is a ubiquitous, highly conserved thioredoxin-like protein whose depletion causes a p53- and p21Cip1-dependent G1-phase cell cycle arrest in breast and prostate epithelial cells. SEPW1 depletion increases phosphorylation of Ser33 in p53, which is associated with decreased p53...

  4. The Mutational Spectrum of Holoprosencephaly-Associated Changes within the SHH Gene in Humans Predicts Loss-of-Function Through Either Key Structural Alterations of the Ligand or Its Altered Synthesis

    OpenAIRE

    Roessler, Erich; El-Jaick, Kenia B.; Dubourg, Christèle; Vélez, Jorge I.; Solomon, Benjamin D.; Pineda-Álvarez, Daniel E.; Lacbawan, Felicitas; Zhou, Nan; Ouspenskaia, Maia; Paulussen, Aimée; Smeets, Hubert J.; Hehr, Ute; Bendavid, Claude; Bale, Sherri; Odent, Sylvie

    2009-01-01

    Mutations within either the SHH gene or its related pathway components are the most common, and best understood, pathogenetic changes observed in holoprosencephaly patients; this fact is consistent with the essential functions of this gene during forebrain development and patterning. Here we summarize the nature and types of deleterious sequence alterations among over one hundred distinct mutations in the SHH gene (64 novel mutations) and compare these to over a dozen mutations in disease-rel...

  5. The mutational spectrum of holoprosencephaly-associated changes within the SHH gene in humans predicts loss-of-function through either key structural alterations of the ligand or its altered synthesis.

    Science.gov (United States)

    Roessler, Erich; El-Jaick, Kenia B; Dubourg, Christèle; Vélez, Jorge I; Solomon, Benjamin D; Pineda-Alvarez, Daniel E; Lacbawan, Felicitas; Zhou, Nan; Ouspenskaia, Maia; Paulussen, Aimée; Smeets, Hubert J; Hehr, Ute; Bendavid, Claude; Bale, Sherri; Odent, Sylvie; David, Véronique; Muenke, Maximilian

    2009-10-01

    Mutations within either the SHH gene or its related pathway components are the most common, and best understood, pathogenetic changes observed in holoprosencephaly patients; this fact is consistent with the essential functions of this gene during forebrain development and patterning. Here we summarize the nature and types of deleterious sequence alterations among over one hundred distinct mutations in the SHH gene (64 novel mutations) and compare these to over a dozen mutations in disease-related Hedgehog family members IHH and DHH. This combined structural analysis suggests that dysfunction of Hedgehog signaling in human forebrain development can occur through truncations or major structural changes to the signaling domain, SHH-N, as well as due to defects in the processing of the mature ligand from its pre-pro-precursor or defective post-translation bi-lipid modifications with palmitate and cholesterol. PMID:19603532

  6. Progress of the study on genetic polymorphisms of Selenoprotein P%硒蛋白P基因多态性的研究进展

    Institute of Scientific and Technical Information of China (English)

    孙文艳; 陈群; 熊咏民

    2009-01-01

    硒蛋白是人和动物必需微量元素硒的主要功能表现形式,硒蛋白P(Selenoprotein P,SEPP)是其中比较特殊的一种,近年来对硒蛋白P的研究越来越多,尤其是硒蛋白P基因多态性与疾病的关系也日益受到关注.鉴于硒蛋白P基因多态性对疾病易感性的意义,本文从硒蛋白P的分子生物学特点、生物功能以及基因多态性与疾病关系的研究进展进行综述,以期为缺硒性地方病的研究开拓新的思路.

  7. Characterization of the aerosol produced by infrared femtosecond laser ablation of polyacrylamide gels for the sensitive inductively coupled plasma mass spectrometry detection of selenoproteins

    International Nuclear Information System (INIS)

    A 2D high repetition rate femtosecond laser ablation strategy (2-mm wide lane) previously developed for the detection of selenoproteins in gel electrophoresis by inductively coupled plasma mass spectrometry was found to increase signal sensitivity by a factor of 40 compared to conventional nanosecond ablation (0.12-mm wide lane) [G. Ballihaut, F. Claverie, C. Pecheyran, S. Mounicou, R. Grimaud and R. Lobinski, Sensitive Detection of Selenoproteins in Gel Electrophoresis by High Repetition Rate Femtosecond Laser Ablation-Inductively Coupled Plasma Mass Spectrometry, Anal. Chem. 79 (2007) 6874-6880]. Such improvement couldn't be explained solely by the difference of amount of material ablated, and then, was attributed to the aerosol properties. In order to validate this hypothesis, the characterization of the aerosol produced by nanosecond and high repetition rate femtosecond laser ablation of polyacrylamide gels was investigated. Our 2D high repetition rate femtosecond laser ablation strategy of 2-mm wide lane was found to produce aerosols of similar particle size distribution compared to nanosecond laser ablation of 0.12-mm wide lane, with 38% mass of particles < 1 μm. However, at high repetition rate, when the ablated surface was reduced, the particle size distribution was shifted toward thinner particle diameter (up to 77% for a 0.12-mm wide lane at 285 μm depth). Meanwhile, scanning electron microscopy was employed to visualize the morphology of the aerosol. In the case of larger ablation, the fine particles ejected from the sample were found to form agglomerates due to higher ablation rate and then higher collision probability. Additionally, investigations of the plasma temperature changes during the ablation demonstrated that the introduction of such amount of polyacrylamide gel particles had very limited impact on the ICP source (ΔT∼ 25 ± 5 K). This suggests that the cohesion forces between the thin particles composing these large aggregates were weak

  8. Characterization of the aerosol produced by infrared femtosecond laser ablation of polyacrylamide gels for the sensitive inductively coupled plasma mass spectrometry detection of selenoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Claverie, Fanny [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l' Environnement et les Materiaux, UMR 5254 CNRS- Universite de Pau et des Pays de l' Adour, Helioparc Pau-Pyrenees, 2 Avenue du President Angot, 64053 Pau Cedex 9 (France); Novalase SA, Z.I de la Briqueterie, 6 Impasse du bois de la Grange, 33610 Canejan (France); Pecheyran, Christophe [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l' Environnement et les Materiaux, UMR 5254 CNRS- Universite de Pau et des Pays de l' Adour, Helioparc Pau-Pyrenees, 2 Avenue du President Angot, 64053 Pau Cedex 9 (France)], E-mail: Christophe.pecheyran@univ-pau.fr; Mounicou, Sandra [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l' Environnement et les Materiaux, UMR 5254 CNRS- Universite de Pau et des Pays de l' Adour, Helioparc Pau-Pyrenees, 2 Avenue du President Angot, 64053 Pau Cedex 9 (France); Ballihaut, Guillaume [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l' Environnement et les Materiaux, UMR 5254 CNRS- Universite de Pau et des Pays de l' Adour, Helioparc Pau-Pyrenees, 2 Avenue du President Angot, 64053 Pau Cedex 9 (France); Laboratoire d' Ecologie Moleculaire (Microbiologie), UMR 5254 CNRS- Universite de Pau et des Pays de l' Adour, avenue de l' Universite, B.P. 1155, F-64013 Pau (France); Fernandez, Beatriz [Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l' Environnement et les Materiaux, UMR 5254 CNRS- Universite de Pau et des Pays de l' Adour, Helioparc Pau-Pyrenees, 2 Avenue du President Angot, 64053 Pau Cedex 9 (France); Alexis, Joel [Laboratoire Genie de Production, Ecole Nationale d' Ingenieurs de Tarbes, 47 avenue d' Azereix BP 1629, 65016 Tarbes (France)] (and others)

    2009-07-15

    A 2D high repetition rate femtosecond laser ablation strategy (2-mm wide lane) previously developed for the detection of selenoproteins in gel electrophoresis by inductively coupled plasma mass spectrometry was found to increase signal sensitivity by a factor of 40 compared to conventional nanosecond ablation (0.12-mm wide lane) [G. Ballihaut, F. Claverie, C. Pecheyran, S. Mounicou, R. Grimaud and R. Lobinski, Sensitive Detection of Selenoproteins in Gel Electrophoresis by High Repetition Rate Femtosecond Laser Ablation-Inductively Coupled Plasma Mass Spectrometry, Anal. Chem. 79 (2007) 6874-6880]. Such improvement couldn't be explained solely by the difference of amount of material ablated, and then, was attributed to the aerosol properties. In order to validate this hypothesis, the characterization of the aerosol produced by nanosecond and high repetition rate femtosecond laser ablation of polyacrylamide gels was investigated. Our 2D high repetition rate femtosecond laser ablation strategy of 2-mm wide lane was found to produce aerosols of similar particle size distribution compared to nanosecond laser ablation of 0.12-mm wide lane, with 38% mass of particles < 1 {mu}m. However, at high repetition rate, when the ablated surface was reduced, the particle size distribution was shifted toward thinner particle diameter (up to 77% for a 0.12-mm wide lane at 285 {mu}m depth). Meanwhile, scanning electron microscopy was employed to visualize the morphology of the aerosol. In the case of larger ablation, the fine particles ejected from the sample were found to form agglomerates due to higher ablation rate and then higher collision probability. Additionally, investigations of the plasma temperature changes during the ablation demonstrated that the introduction of such amount of polyacrylamide gel particles had very limited impact on the ICP source ({delta}T{approx} 25 {+-} 5 K). This suggests that the cohesion forces between the thin particles composing these large

  9. Kefir consumption does not alter plasma lipid levels or cholesterol fractional synthesis rates relative to milk in hyperlipidemic men: a randomized controlled trial [ISRCTN10820810

    Directory of Open Access Journals (Sweden)

    Mafu Akier

    2002-01-01

    Full Text Available Abstract Background Fermented milk products have been shown to affect serum cholesterol concentrations in humans. Kefir, a fermented milk product, has been traditionally consumed for its potential health benefits but has to date not been studied for its hypocholesterolemic properties. Methods Thirteen healthy mildly hypercholesterolemic male subjects consumed a dairy supplement in randomized crossover trial for 2 periods of 4 wk each. Subjects were blinded to the dairy supplement consumed. Blood samples were collected at baseline and after 4 wk of supplementation for measurement of plasma total, low-density lipoprotein, and high-density lipoprotein cholesterol and triglyceride concentrations, as well as fatty acid profile and cholesterol synthesis rate. Fecal samples were collected at baseline and after 2 and 4 wk of supplementation for determination of fecal short chain fatty acid level and bacterial content. Results Kefir had no effect on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglyceride concentrations nor on cholesterol fractional synthesis rates after 4 wk of supplementation. No significant change on plasma fatty acid levels was observed with diet. However, both kefir and milk increased (p Conclusions Since kefir consumption did not result in lowered plasma lipid concentrations, the results of this study do not support consumption of kefir as a cholesterol-lowering agent.

  10. Research Progress in Selenoproteins and Their Modulatory Effects on Macrophage Functions%硒蛋白及其对巨噬细胞功能调节作用的研究进展

    Institute of Scientific and Technical Information of China (English)

    孙纳新; 王成华

    2012-01-01

    Selenium can exert its physiological tractions in the form of selenoproteins in immune system. Macrophages play a pivotal role in immune regulation and bacterial defense. Recently, it has been found by using mice fed on selenium-rich diets, gene knockout mice and monoclonal antibody technology that selenoproteins have significant impact on redox status, migration and inflammatory responses of macrophages. In this article, we review recent research advances in the effects of selenoproteins on redox level, walk characteristics and inflammation in macrophages at the molecular level. This review suggests that selenoproteins may have complicated molecular modulation mechanisms and prospect medicinal benefits.%硒蛋白作为体内硒的主要存在形式,在免疫反应等许多方面发挥重要的生理功能,而巨噬细胞则在免疫调节与抗微生物感染等方面具有关键作用。近年来,通过硒饲喂实验、基因敲除、单克隆抗体等多种实验手段,发现硒蛋白对巨噬细胞功能具有重要的调节作用。本文总结近年来硒蛋白在分子水平上,对巨噬细胞胞内的氧化还原水平、游走特征以及炎症反应影响,显示出硒蛋白在免疫反应中的复杂分子调节机制及未来的药用前景。

  11. Altered levels of LIL3 isoforms in Arabidopsis lead to disturbed pigment-protein assembly and chlorophyll synthesis, chlorotic phenotype and impaired photosynthetic performance.

    Science.gov (United States)

    Lohscheider, Jens N; Rojas-Stütz, Marc C; Rothbart, Maxi; Andersson, Ulrica; Funck, Dietmar; Mendgen, Kurt; Grimm, Bernhard; Adamska, Iwona

    2015-10-01

    Light-harvesting complex (LHC)-like (LIL) proteins contain two transmembrane helices of which the first bears a chlorophyll (Chl)-binding motif. They are widespread in photosynthetic organisms, but almost nothing is known about their expression and physiological functions. We show that two LIL3 paralogues (LIL3:1 and LIL3:2) in Arabidopsis thaliana are expressed in photosynthetically active tissues and their expression is differentially influenced by light stress. Localization studies demonstrate that both isoforms are associated with subcomplexes of LHC antenna of photosystem II. Transgenic plants with reduced amounts of LIL3:1 exhibited a slightly impaired growth and have reduced Chl and carotenoid contents as compared to wild-type plants. Ectopic overexpression of either paralogue led to a developmentally regulated switch to co-suppression of both LIL3 isoforms, resulting in a circular chlorosis of the leaf rosettes. Chlorotic sectors show severely diminished levels of LIL3 isoforms and other proteins, and thylakoid morphology was changed. Additionally, the levels of enzymes involved in Chl biosynthesis are altered in lil3 mutant plants. Our data support a role of LIL3 paralogues in the regulation of Chl biosynthesis under light stress and under standard growth conditions as well as in a coordinated ligation of newly synthesized and/or rescued Chl molecules to their target apoproteins. PMID:25808681

  12. Smectite alteration

    International Nuclear Information System (INIS)

    This report contains the proceedings of a second workshop in Washington DC December 8-9, 1983 on the alteration of smectites intended for use as buffer materials in the long-term containment of nuclear wastes. It includes extended summaries of all presentations and a transcript of the detailed scientific discussion. The discussions centered on three main questions: What is the prerequisite for and what is the precise mechanism by which smectite clays may be altered to illite. What are likly sources of potassium with respect to the KBS project. Is it likely that the conversion of smectite to illite will be of importance in the 10 5 to the 10 6 year time frame. The workshop was convened to review considerations and conclusions in connection to these questions and also to broaden the discussion to consider the use of smectite clays as buffer materials for similar applications in different geographical and geological settings. SKBF/KBS technical report 83-03 contains the proceedings from the first workshop on these matters that was held at the State University of New York, Buffalo May 26-27, 1982. (Author)

  13. Selenoprotein S (SEPS1 gene -105G>A promoter polymorphism influences the susceptibility to gastric cancer in the Japanese population

    Directory of Open Access Journals (Sweden)

    Nagasaka Mitsuo

    2009-01-01

    Full Text Available Abstract Background Inflammation is a key factor in the process of carcinogenesis from chronic gastritis induced by Helicobacter pylori. Selenoprotein S (SEPS1 is involved in the control of the inflammatory response in the endoplasmic reticulum (ER. Recently the -105G>A polymorphism in the promoter of SEPS1 was shown to increase pro-inflammatory cytokine expression. We examined the association between this polymorphism and the risk of gastric cancer. Methods We took stomach biopsies during endoscopies of 268 Japanese gastric cancer patients (193 males and 75 females, average age 65.3, and 306 control patients (184 males and 122 females, average age 62.7 and extracted the DNA from the biopsy specimens. All subjects provided written informed consent. For the genotyping of the SEPS1 promoter polymorphism at position -105G>A, PCR-RFLP methods were used and the PCR products were digested with PspGI. Logistic-regression analysis was used to estimate odds ratios (OR and 95% confidence intervals (CI, adjusting for age, sex, and H. pylori infection status. Results Among cases, the distribution of genotypes was as follows: 88.4% were GG, 11.2% were GA, and 0.4% were AA. Among controls, the distribution was as follows: 92.5% were GG, 7.2% were GA, and 0.3% were AA. Among males, carrying the A allele was associated with an increased odds of gastric cancer, compared with the GG genotype (OR: 2.0, 95% CI 1.0–4.1, p = 0.07. Compared with the GG genotype, carrying the A allele was significantly associated with increased risks of intestinal type gastric cancer (OR: 2.0, 95%CI 1.0–3.9, p Conclusion The -105G>A promoter polymorphism of SEPS1 was associated with the intestinal type of gastric cancer. This polymorphism may influence the inflammatory conditions of gastric mucosa. Larger population-based studies are needed for clarifying the relation between inflammatory responses and SEPS1 polymorphism.

  14. Selenium and Chronic Diseases: A Nutritional Genomics Perspective

    Directory of Open Access Journals (Sweden)

    Catherine Méplan

    2015-05-01

    Full Text Available Mechanistic data have revealed a key role for selenium (Se and selenoproteins in biological pathways known to be altered in multifactorial diseases, such as cellular maintenance, response to oxidative stress and correct protein folding. Although epidemiological studies indicate that low Se intake is linked to increased risk for various chronic diseases, supplementation trials have given confusing outcomes, suggesting that additional genetic factors could affect the relationship between Se and health. Genetic data support this hypothesis, as risk for several chronic diseases, in particular cancer, was linked to a number of single nucleotide polymorphisms (SNP altering Se metabolism, selenoprotein synthesis or activity. Interactions between SNPs in selenoprotein genes, SNPs in related molecular pathways and biomarkers of Se status were found to further modulate the genetic risk carried by the SNPs. Taken together, nutritional genomics approaches uncovered the potential implication of some selenoproteins as well as the influence of complex interactions between genetic variants and Se status in the aetiology of several chronic diseases. This review discusses the results from these genetic associations in the context of selenoprotein functions and epidemiological investigations and emphasises the need to assess in future studies the combined contribution of Se status, environmental stress, and multiple or individual SNPs to disease risk.

  15. Selenoprotein P and apolipoprotein E receptor-2 interact at the blood-brain barrier and also within the brain to maintain an essential selenium pool that protects against neurodegeneration

    Science.gov (United States)

    Burk, Raymond F.; Hill, Kristina E.; Motley, Amy K.; Winfrey, Virginia P.; Kurokawa, Suguru; Mitchell, Stuart L.; Zhang, Wanqi

    2014-01-01

    Selenoprotein P (Sepp1) and its receptor, apolipoprotein E receptor 2 (apoER2), account for brain retaining selenium better than other tissues. The primary sources of Sepp1 in plasma and brain are hepatocytes and astrocytes, respectively. ApoER2 is expressed in varying amounts by tissues; within the brain it is expressed primarily by neurons. Knockout of Sepp1 or apoER2 lowers brain selenium from ∼120 to ∼50 ng/g and leads to severe neurodegeneration and death in mild selenium deficiency. Interactions of Sepp1 and apoER2 that protect against this injury have not been characterized. We studied Sepp1, apoER2, and brain selenium in knockout mice. Immunocytochemistry showed that apoER2 mediates Sepp1 uptake at the blood-brain barrier. When Sepp1−/− or apoER2−/− mice developed severe neurodegeneration caused by mild selenium deficiency, brain selenium was ∼35 ng/g. In extreme selenium deficiency, however, brain selenium of ∼12 ng/g was tolerated when both Sepp1 and apoER2 were intact in the brain. These findings indicate that tandem Sepp1-apoER2 interactions supply selenium for maintenance of brain neurons. One interaction is at the blood-brain barrier, and the other is within the brain. We postulate that Sepp1 inside the blood-brain barrier is taken up by neurons via apoER2, concentrating brain selenium in them.—Burk, R. F., Hill, K. E., Motley, A. K., Winfrey, V. P., Kurokawa, S., Mitchell, S. L., Zhang, W. Selenoprotein P and apolipoprotein E receptor-2 interact at the blood-brain barrier and also within the brain to maintain an essential selenium pool that protects against neurodegeneration. PMID:24760755

  16. PROTECTIVE EFFECT OF SOYBEAN SELENOPROTEIN ON MYOCARDIAL INJURIES IN DIABETIC RATS%大豆硒蛋白对糖尿病大鼠心肌损伤的保护作用

    Institute of Scientific and Technical Information of China (English)

    刘红; 阳辉; 艾民仙

    2012-01-01

    目的 探讨大豆硒蛋白对糖尿病大鼠心肌损伤的保护作用.方法 Wistar大鼠50只,,随机分为正常对照组(NC)、糖尿病对照组(DM)、低剂量Se治疗组(L-Se)、中剂量Se治疗组(M-Se)、高剂量Se治疗组(H-Se).后4组腹腔注射链脲佐菌素55 mg/kg制备DM模型.第7w起,NC、DM组于0.5% CMC-Na 10ml/(kg.d),L-Se、M-Se、H-Se组分别予大豆硒蛋白2,4,8g/(kg.d)灌胃.第12w末处死大鼠,检测血糖、血清及心肌组织中SOD、GSH-Px、NOS活性和MDA、NO含量以及心肌组织中Na+-K+-ATPase、Ca2+-ATPase活性.结果 与模型组比较,补充外源性大豆硒蛋白后,M-Se、H-Se组可明显降低糖尿病大鼠血糖及MDA含量(均P<0.001),显著增加血清GSH-Px、NOS活性(P<0.001),同时使心肌线粒GSH-Px活性、NO含量明显增加(均P<0.001),并且使心肌组织Na+-K+-ATPase、Ca2+-ATPase活性显著增加(P<0.01,P<0.001).结论 大豆硒蛋白对糖尿病大鼠心肌损伤具有保护作用.%Objective To investigate the effect of soybean selenoprotein on myocardial injuries in diabetic rats. Method Fifty Wistar rats were randomly divided into five groups: normal control group (NC), diabetic model group (DM), three Se treatment groups (L-Se, M-Se, H-Se). The rats were given ip streptozotocin (STZ) 55 mg/kg except NC group. After 6 w, 2, 4, 8 g/(kg · d) soybean selenoprotein containing 9.48, 18 96, 37.92 μg/(kg·d) Se respecfively were given ig in L-Se, M-Se, H-Se groups. Carboxymethylcellulose-sodium (CMC-Na) was similarly given in NC and DM groups. At the 12th weekend, the rats were killed, and the blood sugar, serum SOD, GSH-Px, NOS activites, MDA, NO contents, and myocardial Na+-K.+-ATPase, Ca2+- ATPase activities were determined. Results Compared to the model group, soybean Se-containing protein could obviously reduce the blood sugar and MDA content of diabetic rats (P <0.001), significantly increase GSH -Px, and NOS activities (P<0.001) in serum, as well as myocardial

  17. Metabolic alterations during ascosporogenesis of Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Sporulation of S. cerevisiae has been shown to alter the profiles of enzymes involved in gluconeogenesis and glycolysis. The enhancement in the levels of total cellular carbohydrates could be correlated with the enhancement in fructose 1,6-diphosphatase and trehalose-phosphate synthetase. The latter activity could account for the 15-fold increase in trehalose levels in sporulating cells. Glucose-6-phosphatase, pyruvate kinase and phosphofructokinase showed continuous decline during ascosporogenesis. The relative incorporation of radioactivity from possible precursors of gluconeogenesis indicated that acetate-2-14C alone could contribute to carbohydrate synthesis. (author)

  18. Attention Alters Perceived Attractiveness.

    Science.gov (United States)

    Störmer, Viola S; Alvarez, George A

    2016-04-01

    Can attention alter the impression of a face? Previous studies showed that attention modulates the appearance of lower-level visual features. For instance, attention can make a simple stimulus appear to have higher contrast than it actually does. We tested whether attention can also alter the perception of a higher-order property-namely, facial attractiveness. We asked participants to judge the relative attractiveness of two faces after summoning their attention to one of the faces using a briefly presented visual cue. Across trials, participants judged the attended face to be more attractive than the same face when it was unattended. This effect was not due to decision or response biases, but rather was due to changes in perceptual processing of the faces. These results show that attention alters perceived facial attractiveness, and broadly demonstrate that attention can influence higher-level perception and may affect people's initial impressions of one another. PMID:26966228

  19. Outer membrane alterations in multiresistant mutants of Pseudomonas aeruginosa selected by ciprofloxacin.

    OpenAIRE

    Legakis, N. J.; Tzouvelekis, L. S.; Makris, A; Kotsifaki, H

    1989-01-01

    Spontaneous mutants of Pseudomonas aeruginosa selected by ciprofloxacin were studied for outer membrane alterations. Acquisition of ciprofloxacin resistance was at least partially related to defects in lipopolysaccharide synthesis. When ciprofloxacin resistance was combined with resistance to beta-lactams and aminoglycosides, several alterations in outer membrane proteins were noted.

  20. Accurate Quantification of Selenoprotein P (SEPP1) in Plasma Using Isotopically Enriched Seleno-peptides and Species-Specific Isotope Dilution with HPLC Coupled to ICP-MS/MS.

    Science.gov (United States)

    Deitrich, Christian L; Cuello-Nuñez, Susana; Kmiotek, Diana; Torma, Frank Attila; Del Castillo Busto, Maria Estela; Fisicaro, Paola; Goenaga-Infante, Heidi

    2016-06-21

    A novel strategy for the absolute quantification of selenium (Se) included in selenoprotein P (SEPP1), an important biomarker for human nutrition and disease, including diabetes and cancer, is presented here for the first time. It is based on the use of species-specific double isotope dilution mass spectrometry (SSIDA) in combination with HPLC-ICP-MS/MS for the determination of protein bound Se down to the peptide level in a complex plasma matrix with a total content of Se of 105.5 μg kg(-1). The method enabled the selective Se speciation analysis of human plasma samples without the need of extensive cleanup or preconcentration steps as required for traditional protein mass spectrometric approaches. To assess the method accuracy, two plasma reference materials, namely, BCR-637 and SRM1950, for which literature data and a reference value for SEPP1 have been reported, were analyzed using complementary hyphenated methods and the species-specific approach developed in this work. The Se mass fractions obtained via the isotopic ratios (78)Se/(76)Se and (82)Se/(76)Se for each of the Se-peptides, namely, ENLPSLCSUQGLR (ENL) and AEENITESCQUR (AEE) (where U is SeCys), were found to agree within 2.4%. A relative expanded combined uncertainty (k = 2) of 5.4% was achieved for a Se (as SEPP1) mass fraction of approximately 60 μg kg(-1). This work represents a systematic approach to the accurate quantitation of plasma SEPP1 at clinical levels using SSIDA quantification. Such methodology will be invaluable for the certification of reference materials and the provision of reference values to clinical measurements and clinical trials. PMID:27108743

  1. Synthesis and characterization of mesoporic materials containing highly dispersed cobalt

    OpenAIRE

    Jentys, A.; Pham, N.H; Vinek, H.; Englisch, M.; Lercher, J.A.

    1996-01-01

    Highly dispersed Co particles in MCM-41 were prepared by direct addition of CoCl2 to the synthesis gel. The small clusters of Co did not sinter during reduction and sulfidation. Incorporation of Co into the MCM-41 lattice was not observed. The addition of Co to the synthesis gel did not alter the structural characteristics of the MCM-41 samples.

  2. Molecular characterization and expression analyses of cDNAs encoding the thioredoxin-interacting protein and selenoprotein P genes and histological changes in Nile tilapia (Oreochromis niloticus) in response to silver nanoparticle exposure.

    Science.gov (United States)

    Thummabancha, Kubpaphas; Onparn, Nuttaphon; Srisapoome, Prapansak

    2016-02-15

    Herein, Nile tilapia thioredoxin-interacting protein (On-TXNIP) and selenoprotein P (On-SEPP) cDNAs were cloned and characterized. The full-length On-TXNIP cDNA contained 2 arrestin domains, 2 conserved cysteine residues that bind to thioredoxin to inhibit thioredoxin function, and 2 PPXY motifs, which negatively regulate the protein by stimulating binding to E3 ubiquitin ligase. The On-SEPP cDNA contained 17 selenocysteines (Sec) encoded by the TGA codon, which can be recognized as either a stop codon or a Sec codon. The On-SEPP cDNA also carried 2 typical SECIS elements located in the 3'UTR that are important for selenocysteine translation. Evolutionary analyses of both the On-TXNIP and On-SEPP genes revealed that these genes are closely related to the TXNIP and SEPP genes in zebrafish (Danio rerio), with amino acid similarities of 91.8% and 61.9%, respectively. A normal tissue distribution analysis indicated that the On-TXNIP and On-SEPP genes were ubiquitously expressed in all tissues examined, and the highest expression levels of these genes were observed in peripheral blood leukocytes (PBLs) and the trunk kidney, respectively. The expression levels of On-TXNIP and On-SEPP transcripts were acutely and chronically analyzed following the injection of fish with 1, 10 or 100mg/kg silver nanoparticles (Ag NPs). Significant up-regulation of On-TXNIP and On-SEPP transcripts was observed in the liver, spleen, and head kidney at the early phase of Ag NP exposure (hours 6 through 48). Down-regulation of On-SEPP transcripts was clearly observed in the liver at weeks 1 to 4. Histopathology analysis demonstrated that the fish livers exhibited a dramatic infiltration of Kupffer cells, elevated bi-nucleated cells, expanded sinusoidal blood congestion and severe necrosis in a dose-dependent manner. Based on these findings, coupling of the expression analysis of these two cellular stress response genes and histopathological observation of fish exposed to Ag NPs should be

  3. Aqueous extracts of selenium-fertilized broccoli increase selenoprotein activity and inhibit DNA single-strand breaks, but decrease the activity of quinone reductase in Hepa 1c1c7 cells.

    Science.gov (United States)

    Keck, Anna-Sigrid; Finley, John W

    2006-05-01

    Depending on growth conditions, broccoli may be enriched in the isothiocyanate sulforaphane and/or the mineral selenium (Se); both compounds may play an important role in the reduction of intracellular oxidative stress and chronic disease prevention. Sulforaphane up-regulates transcription of Phase II detoxification proteins (e.g. quinone reductase [QR]), whereas Se is needed for the production of thioredoxin reductase (TR) and glutathione peroxidase-1 (GPx1), both of which exhibit antioxidant activity. The objective of the present study was to determine whether the fertilization of broccoli with Se increases the antioxidant ability of broccoli. Hydrogen peroxide-induced DNA single-strand breaks (measured by single cell electrophoresis, Comet assay) and activity of antioxidant enzymes (GPx, TR and QR) were measured in mouse hepatoma cells (Hepa 1c1c7 cells) treated with purified sulforaphane, sodium selenite or extracts of selenized broccoli. When supplied separately as chemically pure substances, sodium selenite was more effective than sulforaphane for reduction of single-strand breaks. Se-fertilized broccoli extracts were the most effective for reduction of DNA single-strand breaks, and extracts that contained 0.71 microM Se and 0.08 microM sulforaphane inhibited 94% of DNA single-strand breaks. A significant positive association (r = 0.81, p = 0.009) between GPx1 activity and inhibition of DNA single-strand breaks as well as a 24h lag time between addition of Se, sulforaphane or broccoli extract and inhibition of single-strand breaks suggests that some of the antioxidant protection is mediated through selenoproteins. Conversely, fertilization of broccoli with Se decreased the ability of broccoli extract to induce QR activity. These results demonstrate that Se and sulforaphane, alone or as a component of broccoli, may help decrease oxidative stress. They further suggest that Se is the most important for decreasing oxidative stress, but maximizing the Se content

  4. Organic synthesis

    International Nuclear Information System (INIS)

    The 1988 progress report of the Organic Synthesis Chemistry laboratory (Polytechnic School, France), is presented. The laboratory activities are centered on the chemistry of natural products, which have a biological activity and on the development of new reactions, useful in the organic synthesis. The research works involve the following domains: the natural products chemistry which are applied in pharmacology, the plants and insects chemistry, the organic synthesis, the radical chemistry new reactions and the bio-organic physicochemistry. The published papers, the congress communications and the thesis are listed

  5. Alterations in phosphatidylcholine synthesis are associated with taxol resistance

    International Nuclear Information System (INIS)

    A taxol resistant variant (J7/TAX-50) of the murine macrophage-like cell line J774.2 has been developed in vitro. The LD50 of taxol for the resistant cells is 800-fold greater than that for the parental cell line. The J7/TAX-50 cells display phenotypic traits which are associated with multidrug resistance. J7/TAX-50 is unstably resistant and must be maintained in the presence of taxol. Cells grown in the absence of taxol for 30 days revert to drug sensitivity, and the membrane phosphoglycoprotein is lost. In contrast, the return to a normal level of drug accumulation is prolonged and requires over 8 months of growth in the absence of taxol. To characterize further the parental, resistant and revertant cell lines, the major lipids have been analyzed by 2D-chromatography and HPLC. The steady-state level of phosphatidylcholine (PC) in J7/TAX-50 is greater than in the parental or revertant cell lines. Pulse-chase studies performed with 14C-choline or 32P-orthophosphate demonstrated an increase in the turnover of PC in J7/TAX-50. Analysis by gas chromatography/mass spectrometry of the composition of the major phospholipids indicated that fatty acids attached to the sn1- and 2-positions of PC are the same in the resistant and parental cell lines. These studies suggest that an increased level of PC in the membrane may be related to drug resistance and responsible for the prolonged decrease in steady-state drug association in J7/TAX-50 grown in the absence of taxol

  6. Alterations in gastric mucin synthesis by Helicobacter p ylori

    Institute of Scientific and Technical Information of China (English)

    James C. Byrd; Robert S. Bresalier

    2000-01-01

    Helicobacter pylori is recognized as a cause of chronic active gastritis, gastric and duodenal ulcers, and gastric cancer, though the mechanisms of pathogenesis for H. pylori-associated diseases are not yet well understood[1 -4] The ecological niche to which H. pylori is well-adapted is the mucous layer of the human gastric antrum, which has mucin glycoproteins as major constituents. Mucins, highmolecular weight carbohydrate-rich glycoproteins that coat the surface of the stomach and are secreted into the lumen, function to protect the stomach and could be important in H. pylori colonization. For further understanding the pathogenesis of H. pylori-related diseases, it is important to consider whether H. pylori colonization of the surface epithelium is associated, as cause or effect, with changes in the gastric mucin synthesized by surface mucous cells.

  7. Altered fingerprints: analysis and detection.

    Science.gov (United States)

    Yoon, Soweon; Feng, Jianjiang; Jain, Anil K

    2012-03-01

    The widespread deployment of Automated Fingerprint Identification Systems (AFIS) in law enforcement and border control applications has heightened the need for ensuring that these systems are not compromised. While several issues related to fingerprint system security have been investigated, including the use of fake fingerprints for masquerading identity, the problem of fingerprint alteration or obfuscation has received very little attention. Fingerprint obfuscation refers to the deliberate alteration of the fingerprint pattern by an individual for the purpose of masking his identity. Several cases of fingerprint obfuscation have been reported in the press. Fingerprint image quality assessment software (e.g., NFIQ) cannot always detect altered fingerprints since the implicit image quality due to alteration may not change significantly. The main contributions of this paper are: 1) compiling case studies of incidents where individuals were found to have altered their fingerprints for circumventing AFIS, 2) investigating the impact of fingerprint alteration on the accuracy of a commercial fingerprint matcher, 3) classifying the alterations into three major categories and suggesting possible countermeasures, 4) developing a technique to automatically detect altered fingerprints based on analyzing orientation field and minutiae distribution, and 5) evaluating the proposed technique and the NFIQ algorithm on a large database of altered fingerprints provided by a law enforcement agency. Experimental results show the feasibility of the proposed approach in detecting altered fingerprints and highlight the need to further pursue this problem. PMID:21808092

  8. Nucleolar proteins change in altered gravity

    Science.gov (United States)

    Sobol, M. A.; Kordyum, E. L.; Gonzalez-Camacho, F.; Medina, F. J.

    Discovery of gravisensitivity of cells no specified to gravity perception focused continuous attention on an elucidation of mechanisms involved in altered gravity effects at the different levels of cellular organization A nucleolus is the nuclear domain in which the major portion of ribosome biogenesis takes place This is a basic process for cell vitality beginning with the transcription of rDNA followed by processing newly synthesized pre-rRNA molecules A wide range of nucleolar proteins plays a highly significant role in all stages of biosynthesis of ribosomes Different steps of ribosome biogenesis should respond to various external factors affecting generally the cell metabolism Nevertheless a nucleolus remains not enough studied under the influence of altered environmental conditions For this reason we studied root apices from 2-day old Lepidium sativum seedlings germinated and grown under slow horizontal clinorotation and stationary conditions in darkness The extraction of cell nuclei followed by sequential fractionation of nuclear proteins according to their solubility in buffers of increasing ionic strength was carried out This procedure gave rise to 5 distinct fractions We analyzed nuclear subproteomes of the most soluble fraction called S2 It is actually a functionally significant fraction consisting of ribonucleoproteins actively engaged in pre-rRNA synthesis and processing 2D-electrophoresis of S2 fraction proteins was carried out The gels were silver stained and stained gels were scanned and analyzed

  9. Music alters visual perception.

    Directory of Open Access Journals (Sweden)

    Jacob Jolij

    Full Text Available BACKGROUND: Visual perception is not a passive process: in order to efficiently process visual input, the brain actively uses previous knowledge (e.g., memory and expectations about what the world should look like. However, perception is not only influenced by previous knowledge. Especially the perception of emotional stimuli is influenced by the emotional state of the observer. In other words, how we perceive the world does not only depend on what we know of the world, but also by how we feel. In this study, we further investigated the relation between mood and perception. METHODS AND FINDINGS: We let observers do a difficult stimulus detection task, in which they had to detect schematic happy and sad faces embedded in noise. Mood was manipulated by means of music. We found that observers were more accurate in detecting faces congruent with their mood, corroborating earlier research. However, in trials in which no actual face was presented, observers made a significant number of false alarms. The content of these false alarms, or illusory percepts, was strongly influenced by the observers' mood. CONCLUSIONS: As illusory percepts are believed to reflect the content of internal representations that are employed by the brain during top-down processing of visual input, we conclude that top-down modulation of visual processing is not purely predictive in nature: mood, in this case manipulated by music, may also directly alter the way we perceive the world.

  10. Genetic Alterations in Glioma

    International Nuclear Information System (INIS)

    Gliomas are the most common type of primary brain tumor and have a dismal prognosis. Understanding the genetic alterations that drive glioma formation and progression may help improve patient prognosis by identification of novel treatment targets. Recently, two major studies have performed in-depth mutation analysis of glioblastomas (the most common and aggressive subtype of glioma). This systematic approach revealed three major pathways that are affected in glioblastomas: The receptor tyrosine kinase signaling pathway, the TP53 pathway and the pRB pathway. Apart from frequent mutations in the IDH1/2 gene, much less is known about the causal genetic changes of grade II and III (anaplastic) gliomas. Exceptions include TP53 mutations and fusion genes involving the BRAF gene in astrocytic and pilocytic glioma subtypes, respectively. In this review, we provide an update on all common events involved in the initiation and/or progression across the different subtypes of glioma and provide future directions for research into the genetic changes

  11. Organic Synthesis

    OpenAIRE

    Romea, Pedro

    2014-01-01

    Organic Synthesis is a one-semester course of the fourth year of the Chemistry Degree at the Universitat de Barcelona. This course covers the most important transformations in Organic Chemistry, including a short introduction to the Retrosynthetic Analysis. The aim is to provide a solid knowledge of the main reactions and their mechanism, which could later be improved during Master studies.

  12. Epigenetic alterations in gastric carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    In-Seon CHOI; Tsung-Teh WU

    2005-01-01

    Gastric cancer is believed to result in part from the accumulation of multiple genetic alterations leading to oncogene overexpression and tumor suppressor loss. Epigenetic alterations as a distinct and crucial mechanism to silence a variety of methylated tissue-specific and imprinted genes, have been extensively studied in gastric carcinoma and play important roles in gastric carcinogenesis. This review will briefly discuss the basic aspects of DNA methylation and CpG island methylation, in particular the epigenetic alterations of certain critical genes implicated in gastric carcinogenesis and its relevance of clinical implications.

  13. Pulmonary alterations in Behcet's disease

    International Nuclear Information System (INIS)

    Purpose: This study aims to demonstrate pulmonary alterations (PA) in patients with Behcet's disease by using CT. Materials and methods: CTs of 50 patients with Behcet's disease and 20 others in a control group have been evaluated retrospectively for PA (septal, reticular, nodular, atelectatic opacities). Results: Eight out of 50 patients (16%) with Behcet's disease showed PA. Three out of 20 (15%) in the control group showed PA. No differences were observed between Behcet's disease patients and the control group regarding pulmonary alterations (p = 0.917). No differences were observed in the disease duration, ages and sex in either group in those with and without PA. Conclusion: Pulmonary alterations can be seen in patients with Behcet's disease, but these alterations are not significant.

  14. No indications for altered essential fatty acid metabolism in two murine models for cystic fibrosis

    NARCIS (Netherlands)

    Werner, A; Bongers, MEJ; Bijvelds, MJ; de Jonge, HR; Verkade, HJ

    2004-01-01

    A deficiency of essential fatty acids (EFA) is frequently described in cystic fibrosis (CF), but whether this is a primary consequence of altered EFA metabolism or a secondary phenomenon is unclear. It was suggested that defective long-chain polyunsaturated fatty acid (LCPUFA) synthesis contributes

  15. Synthesis of chemically modified DNA.

    Science.gov (United States)

    Shivalingam, Arun; Brown, Tom

    2016-06-15

    Naturally occurring DNA is encoded by the four nucleobases adenine, cytosine, guanine and thymine. Yet minor chemical modifications to these bases, such as methylation, can significantly alter DNA function, and more drastic changes, such as replacement with unnatural base pairs, could expand its function. In order to realize the full potential of DNA in therapeutic and synthetic biology applications, our ability to 'write' long modified DNA in a controlled manner must be improved. This review highlights methods currently used for the synthesis of moderately long chemically modified nucleic acids (up to 1000 bp), their limitations and areas for future expansion. PMID:27284032

  16. Synthesis and evaluation of novel carbocyclic carbohydrate analogues

    OpenAIRE

    Adamson, Christopher William

    2016-01-01

    Carbohydrate analogues play an indispensible role in the study of glycan processing enzymes. These compounds have attracted attention as probes of enzyme mechanisms, as chemical tools for the elucidation of enzyme function and as potential pharmaceuticals. The development of organocatalytic aldol chemistry has fundamentally altered the way chemists approach the synthesis of carbohydrate analogues. In this thesis I highlight a novel strategy toward the synthesis of carbocyclic carbohydrate ana...

  17. Effect of inhibitors of prostaglandin synthesis on hepatic drug clearance.

    OpenAIRE

    Feely, J; Wood, A. J.

    1983-01-01

    The effect of inhibition of prostaglandin synthesis on the systemic clearance of indocyanine green and antipyrine was studied in seven subjects. Antipyrine clearance was not altered by indomethacin suggesting that oxidative metabolism was not affected. Both aspirin and indomethacin decreased the clearance of indocyanine green presumably by reducing liver blood flow. These results suggest that an effect of inhibitors of prostaglandin synthesis on hepatic drug clearance is likely to be confined...

  18. Contrast Negation and Texture Synthesis Differentially Disrupt Natural Texture Appearance

    OpenAIRE

    BenjaminJBalas

    2012-01-01

    Natural textures have characteristic image statistics that make them discriminable from unnatural textures. For example, both contrast negation and texture synthesis alter the appearance of natural textures even though each manipulation preserves some features while disrupting others. Here, we examined the extent to which contrast negation and texture synthesis each introduce or remove critical perceptual features for discriminating unnatural textures from natural textures. We find that both ...

  19. Mechanistic approaches to the study of evolution: the functional synthesis

    OpenAIRE

    Dean, Antony M; Joseph W Thornton

    2007-01-01

    An emerging synthesis of evolutionary biology and experimental molecular biology is providing much stronger and deeper inferences about the dynamics and mechanisms of evolution than were possible in the past. The new approach combines statistical analyses of gene sequences with manipulative molecular experiments to reveal how ancient mutations altered biochemical processes and produced novel phenotypes. This functional synthesis has set the stage for major advances in our understanding of fun...

  20. 2型糖尿病患者硒蛋白P和胰岛素抵抗的相关性%Selenoprotein P in type 2 diabetes mellitus and its association with insulin resistance

    Institute of Scientific and Technical Information of China (English)

    潘洁敏; 于浩泳; 张磊; 韩峻峰; 包玉倩; 贾伟平

    2014-01-01

    Objective To explore the relationship between selenoprotein P ( SEPP ) and insulin resistance in subjects with normal glucose tolerance and type 2 diabetes mellitus .Methods A total of 156 subjects with newly onset diabetes and 64 subjects with normal glucose tolerance were enrolled .Fasting plasma glucose ( FPG ) , fasting insulin ( FIN ) , lipid profile and SEPP level were measured and height , weight and blood pressure were recorded.Insulin resistance index was calculated by homeostatic model assessment ( HOMA-IR).Results The SEPP level was significantly higher in obese and non-obese diabetic groups than control group ((4.43 ±1.95), (3.01 ±1.20) vs (2.34 ±2.30)mmol/L, both P<0.01).The SEPP level was significantly higher in obese subgroup of diabetic group than non -obese subgroup ( P<0.05).The SEPP level was positively correlated with FIN , FPG, body mass index (BMI), triglycerides (TG) and HOMA-IR (r=0.401, 0.202, 0.420, 0.239, 0.445, P<0.05) and negatively with ISI (r=-0.414, P <0.01 ).Multivariate regression analysis demonstrated that SEPP level was independently correlated with insulin resistance (β=0.293, P<0.01).And the independent factors for ISI were systolic pressure, HbA1c and SEPP level (β=-0.195, -0.185 and -0.246, P<0.05).Conclusion Serum SEPP level may be an independent risk factor for insulin resistance regardless of age , blood pressure or lipid profile.%目的:研究健康人和2型糖尿病患者中硒蛋白P ( SEPP )和胰岛素抵抗的相关性。方法入组门诊初发2型糖尿病患者156例和64名健康人作为对照,测定空腹血糖( FPG)、空腹胰岛素( FIN)、血脂谱、SEPP 水平,记录身高、体重和血压,采用稳态模型评估胰岛素抵抗指数(HOMA-IR)和计算胰岛素敏感性指数(ISI)。结果(1)肥胖和非肥胖糖尿病组的SEPP水平均显著高于对照组[(4.43±1.95)、(3.01±1.20)比(2.34±2.30)mmol/L,均P<0.01],肥胖糖尿病组的SEPP水平

  1. Serotonin synthesis studied with positron emission tomography, (PET)

    DEFF Research Database (Denmark)

    Honoré, Per Gustaf Hartvig; Lundquist, Pinelopi

    seroonin synthesis rate. Knowledge of altered 5HT synthesis and release in disease states may furnish basis for effective pharmacotherapy that may improve the care of psychiatric and neurological disease. Validation of PET measurements of the two PET tracers using perturbation showed that 5-hydroxy...... in the presence of NSD1015 which was used to inhibit the decarboxylation step in 5HT synthesis. 5HTP seems thus to have potential for tracking changes in the activity of the biosynthesis enzyme. In contrast, the accumulation of 5HTP was unaffected by clorgyline used to inhibit the metabolism of the...

  2. Art as Alterity in Education

    Science.gov (United States)

    Zhao, Guoping

    2014-01-01

    In education, art has often been perceived as entertainment and decoration and is the first subject to go when there are budget cuts or test-score pressures. Drawing on Emmanuel Lévinas's idea of the primacy of radical alterity that breaks the totality of our being, enables self-transformation and ethics, and ensures community as a totality…

  3. A 15-step synthesis of (+)-ryanodol.

    Science.gov (United States)

    Chuang, Kangway V; Xu, Chen; Reisman, Sarah E

    2016-08-26

    (+)-Ryanodine and (+)-ryanodol are complex diterpenoids that modulate intracellular calcium-ion release at ryanodine receptors, ion channels critical for skeletal and cardiac muscle excitation-contraction coupling and synaptic transmission. Chemical derivatization of these diterpenoids has demonstrated that certain peripheral structural modifications can alter binding affinity and selectivity among ryanodine receptor isoforms. Here, we report a short chemical synthesis of (+)-ryanodol that proceeds in only 15 steps from the commercially available terpene (S)-pulegone. The efficiency of the synthesis derives from the use of a Pauson-Khand reaction to rapidly build the carbon framework and a SeO2-mediated oxidation to install three oxygen atoms in a single step. This work highlights how strategic C-O bond constructions can streamline the synthesis of polyhydroxylated terpenes by minimizing protecting group and redox adjustments. PMID:27563092

  4. Evaluation of flux synthesis algorithms

    International Nuclear Information System (INIS)

    The flux synthesis algorithm which is the best fit to the numerical solution of the multigroup diffusion equations, was determined. Three different types of synthesis were studied: 1) discontinuous synthesis 2) continuous synthesis 3) pseudo-continuous synthesis. A matrix and a differential formulation were developed for the first two types of synthesis. For pseudo-continuous synthesis only the matrix formulation was used. Some tests were performed and the results allowed us to establish the following order of efficiency for the algorithms: 1) continuous synthesis (matrix formulation) 2) continuous synthesis (differential formulation) 3) pseudo-continuous synthesis 4) discontinuous synthesis (matrix formulation) 5) discontinuous synthesis (differential formulation). (Author)

  5. Age and Haplotype Variations within FADS1 Interact and Associate with Alterations in Fatty Acid Composition in Human Male Cortical Brain Tissue

    OpenAIRE

    Freemantle, Erika; Lalovic, Aleksandra; Mechawar, Naguib; Turecki, Gustavo

    2012-01-01

    Fatty acids (FA) play an integral role in brain function and alterations have been implicated in a variety of complex neurological disorders. Several recent genomic studies have highlighted genetic variability in the fatty acid desaturase (FADS1/2/3) gene cluster as an important contributor to FA alterations in serum lipids as well as measures of FA desaturase index estimated by ratios of relevant FAs. The contribution to alterations of FAs within the brain by local synthesis is still a matte...

  6. Chemosensory alterations and cancer therapies

    International Nuclear Information System (INIS)

    Taste and olfaction provide sensory information and sensory pleasure. Cancer therapies affect both. Chemotherapy has not been shown to produce dramatic losses of taste or smell, but systematic studies on various chemotherapeutic agents and types of cancer are lacking. Radiation therapy does produce clear losses of both taste and smell. Both chemotherapy and radiation therapy alter the pleasure produced by taste and smell through the formation of conditioned aversions. That is, foods consumed in proximity with the nausea of therapy come to be unpleasant. The impact of conditioned aversions can be diminished by providing a scapegoat food just before therapy. Alterations in foods may be beneficial to the cancer patient. Increasing the concentrations of flavor ingredients can compensate for sensory losses, and providing pureed foods that retain the cognitive integrity of a meal can benefit the patient who has chewing or swallowing problems

  7. Altered states: psychedelics and anesthetics.

    Science.gov (United States)

    Icaza, Eduardo E; Mashour, George A

    2013-12-01

    The psychedelic experience has been reported since antiquity, but there is relatively little known about the underlying neural mechanisms. A recent neuroimaging study on psilocybin revealed a pattern of decreased cerebral blood flow and functional disconnections that is surprisingly similar to that caused by various anesthetics. In this article, the authors review historical examples of psychedelic experiences induced by general anesthetics and then contrast the mechanisms by which these two drug classes generate altered states of consciousness. PMID:24061599

  8. Buccal alterations in diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Negrato Carlos

    2010-01-01

    Full Text Available Abstract Long standing hyperglycaemia besides damaging the kidneys, eyes, nerves, blood vessels, heart, can also impair the function of the salivary glands leading to a reduction in the salivary flow. When salivary flow decreases, as a consequence of an acute hyperglycaemia, many buccal or oral alterations can occur such as: a increased concentration of mucin and glucose; b impaired production and/or action of many antimicrobial factors; c absence of a metalloprotein called gustin, that contains zinc and is responsible for the constant maturation of taste papillae; d bad taste; e oral candidiasis f increased cells exfoliation after contact, because of poor lubrication; g increased proliferation of pathogenic microorganisms; h coated tongue; i halitosis; and many others may occur as a consequence of chronic hyperglycaemia: a tongue alterations, generally a burning mouth; b periodontal disease; c white spots due to demineralization in the teeth; d caries; e delayed healing of wounds; f greater tendency to infections; g lichen planus; h mucosa ulcerations. Buccal alterations found in diabetic patients, although not specific of this disease, have its incidence and progression increased when an inadequate glycaemic control is present.

  9. Overall Synthesis

    International Nuclear Information System (INIS)

    AMIGO is an OECD/NEA international project on the topic of 'Approaches and Methods for Integrating Geological Information in the Safety Case'. The term safety case here refers to the post-closure safety case for a geological repository for long-lived radioactive waste, and is defined as a synthesis of evidence, analyses and arguments that quantify and substantiate a claim that the repository is safe. Geological or geo-scientific information includes the various types of geophysical, hydrogeological, geochemical and structural information that can contribute to the safety case. The safety case is generally updated periodically throughout the step-wise process of repository siting, planning, construction, operation, as well as prior to closure, and becomes more rigorous over time, as increasing amounts of geological and other data become available, until, for a well-chosen site and design, a point is reached at which the safety case is adequate for repository licensing. AMIGO is structured as a series of workshops. This document summarises the first workshop of the AMIGO series, held at Yverdon-les-Bains, Switzerland, on 3-5 June 2003, a-nd-hosted The focus of the workshop was on 'building confidence (in analyses and arguments that support the safety case) using multiple lines of evidence', but other themes within the overall scope of AMIGO were also discussed, such as the integration of the work of geo-scientists and safety assessors. The main themes addressed by the workshop, which include the topics covered by the Working Group Sessions, can be stated as follows: the role of the geosphere in disposal concepts; the ways in which geological information is used by waste management programmes, and the way in which usage changes as a programme progresses; the synthesis of wide ranging geo-scientific information into a consistent site description or conceptual model; the development of arguments for the long-term safety of disposal systems; the use of multiple lines of

  10. Hormonal regulation of fibrinogen synthesis in cultured hepatocytes.

    Science.gov (United States)

    Grieninger, G; Plant, P W; Liang, T J; Kalb, R G; Amrani, D; Mosesson, M W; Hertzberg, K M; Pindyck, J

    1983-06-27

    Most of what was originally known of the effects of hormones on fibrinogen synthesis was based, as noted above, on experiments involving surgical removal of endocrine glands. Some caution should be exercised when using such in vivo experiments to derive the hormonal requirements of fibrinogen synthesis, however, since multiple hormonal alterations often occur in these animals. The development of a variety of ex vivo systems has allowed investigators to more carefully control the hepatocellular environment. The work of several laboratories, including our own, has now made it clear that hormones and other agents directly stimulate hepatocellular synthesis of fibrinogen. From the studies summarized here, using chick embryo hepatocytes as a model, several generalizations emerge: Fibrinogen synthesis may be considered to be a "constitutive" liver function, since hepatocytes cultured without serum, hormones or other macromolecular supplements synthesize this protein at a basal rate for several days. Addition of certain hormones (e.g. T3, dexamethasone, insulin), individually and in physiological concentrations, elicits an increase in fibrinogen production, varying with each agent in onset, dose, minimum exposure required and accompanying effects on the synthesis of other plasma proteins. Glucocorticoids and thyroid hormones are similar in the selectivity of their stimulation (neither affects albumin or transferrin synthesis) but differ in that thyroid hormones need to be present for just a short "triggering" period. The stimulation of fibrinogen synthesis by insulin occurs only following prolonged exposure to concentrations 10-times higher than the very low doses to which albumin synthesis responds rapidly. PMID:6307104

  11. Multiple scenarios of bentonite alteration

    International Nuclear Information System (INIS)

    Performance assessment for TRU waste repositories has shown that soluble and poorly sorbing nuclides such as I-129 and C-14 dominate the dose. These nuclides are expected to migrate with groundwater flow, hence hydraulic conditions and their evolution with time in the repository are key issues for repository safety. Cementitious material will be used for waste packaging, backfilling and structural material in a TRU waste repository. Bentonite is also expected to be used for some TRU wastes to provide the function of a hydraulic barrier in the disposal system. There is concern that the coexistence of cementitious material and bentonite cause the alteration of smectite due to interaction with hyperalkaline leachates and consequent deleterious perturbation of the function of bentonite as a hydraulic barrier. Many research studies have been performed to identify possible mechanisms of cement-bentonite interaction. However, uncertainties still exist in our understanding of the precise chemical scheme of bentonite alteration in highly alkaline conditions, especially the space and time variation of secondary mineral occurrences. In order to reflect this uncertainty, multiple scenarios of bentonite alteration were developed based on the possible mineralogical changes derived from knowledge of both experiments and observation of natural systems. It was focused that the mineral reaction involving hyperalkaline fluids would thermodynamically depend on the variable chemical condition in bentonite buffer and that kinetics would be important as well as thermodynamic stability in controlling their occurrence, i.e., the kinetic controls may operate to remain metastable minerals over the long term. The mineralogical consequences of the interaction between clays and alkaline fluids are summarized as follows. Clay → C-S-H gel and other solids which can rapidly precipitate. Clay and gel → illite. Clay and gel → metastable zeolite. Clay and gel → metastable zeolite → stable

  12. Acid Sulfate Alteration on Mars

    Science.gov (United States)

    Ming, D. W.; Morris, R. V.

    2016-01-01

    A variety of mineralogical and geochemical indicators for aqueous alteration on Mars have been identified by a combination of surface and orbital robotic missions, telescopic observations, characterization of Martian meteorites, and laboratory and terrestrial analog studies. Acid sulfate alteration has been identified at all three landing sites visited by NASA rover missions (Spirit, Opportunity, and Curiosity). Spirit landed in Gusev crater in 2004 and discovered Fe-sulfates and materials that have been extensively leached by acid sulfate solutions. Opportunity landing on the plains of Meridiani Planum also in 2004 where the rover encountered large abundances of jarosite and hematite in sedimentary rocks. Curiosity landed in Gale crater in 2012 and has characterized fluvial, deltaic, and lacustrine sediments. Jarosite and hematite were discovered in some of the lacustrine sediments. The high elemental abundance of sulfur in surface materials is obvious evidence that sulfate has played a major role in aqueous processes at all landing sites on Mars. The sulfate-rich outcrop at Meridiani Planum has an SO3 content of up to 25 wt.%. The interiors of rocks and outcrops on the Columbia Hills within Gusev crater have up to 8 wt.% SO3. Soils at both sites generally have between 5 to 14 wt.% SO3, and several soils in Gusev crater contain around 30 wt.% SO3. After normalization of major element compositions to a SO3-free basis, the bulk compositions of these materials are basaltic, with a few exceptions in Gusev crater and in lacustrine mudstones in Gale crater. These observations suggest that materials encountered by the rovers were derived from basaltic precursors by acid sulfate alteration under nearly isochemical conditions (i.e., minimal leaching). There are several cases, however, where acid sulfate alteration minerals (jarosite and hematite) formed in open hydrologic systems, e.g., in Gale crater lacustrine mudstones. Several hypotheses have been suggested for the

  13. Interferon-specific effects on protein synthesis in P3HR-1 cells.

    OpenAIRE

    Leanderson, T; Sundström, S; Mårtensson, I L; Ny, T; Lundgren, E.

    1982-01-01

    The effect of interferon (IFN) on protein synthesis was studied in the Burkitt's lymphoma cell line P3HR-1 by [35S]methionine labelling of the cells, followed by two-dimensional gel electrophoresis of cell extracts. De novo synthesis of three proteins (mol. wts. 33 000, 62 000, and 98 000, respectively) and alterations in the rate of synthesis for a small number of additional proteins were observed during the first 12 h of treatment, while the rate of overall protein synthesis was unaffected....

  14. Correlated alteration effects in CM carbonaceous chondrites

    Science.gov (United States)

    Browning, Lauren B.; McSween, Harry Y., Jr.; Zolensky, Michael E.

    1996-07-01

    Three parameters are proposed to determine the relative extent of alteration in CM chondrites. The mineralogic alteration index monitors the relative progress of coupled substitutions in the progressive alteration of cronstedtite to Mg-serpentine and increases with increasing alteration. To calculate values of this index, an algorithm has been developed to estimate the average matrix phyllosilicate composition in individual CM chondrites. The second parameter is the volume percent of isolated matrix silicates, which decreases with progressive alteration due to mineral hydration. Finally, the volume percent of chondrule alteration monitors the extent of chondrule phyllosilicate production and increases as alteration proceeds. These parameters define the first CM alteration scale that relies on multiple indicators of progressive alteration. The following relative order of increasing alteration is established by this model: Murchison ≤ Bells Cochabamba and Boriskino experienced is less precisely constrained, although both fall near the middle of this sequence. A comparison between the mineralogic alteration index and literature values for the whole-rock chemistry of CM chondrites reveals several correlations. A positive, nearly linear correlation between bulk H content and progressive CM alteration suggests an approximately constant production rate of new phyllosilicates relative to the mineralogical transition from cronstedtite to Mg-serpentine. The abundance of trapped planetary 36Ar decreases systematically in progressively altered CM chondrites, suggesting the wholesale destruction of primary noble gas carrier phase (s) by aqueous reactions. Because low temperature fluid-rock reactions are generally associated with large isotopic mass fractionation factors, we also compared our model predictions with δ18O values for bulk CM samples. Although some of these data are poorly resolved, the order of increasing δ18O values approximates the order of increasing

  15. TWO STAGE FRAMEWORK FOR ALTERED FINGERPRINT MATCHING

    OpenAIRE

    T. R. Anoop; M.G. Mini

    2015-01-01

    Fingerprint alteration is the process of masking one’s identity from personal identification systems especially in boarder control security systems. Failure of matching the altered fingerprint of the criminals against the watch list of fingerprints can help them to break the security system. This fact leads to the need of a method for altered fingerprint matching. This paper presents a two stage method for altered fingerprint matching. In first stage, approximated global ridge orientation fie...

  16. Altered hypothalamic protein expression in a rat model of Huntington's disease.

    Directory of Open Access Journals (Sweden)

    Wei-na Cong

    Full Text Available Huntington's disease (HD is a neurodegenerative disorder, which is characterized by progressive motor impairment and cognitive alterations. Changes in energy metabolism, neuroendocrine function, body weight, euglycemia, appetite function, and circadian rhythm can also occur. It is likely that the locus of these alterations is the hypothalamus. We used the HD transgenic (tg rat model bearing 51 CAG repeats, which exhibits similar HD symptomology as HD patients to investigate hypothalamic function. We conducted detailed hypothalamic proteome analyses and also measured circulating levels of various metabolic hormones and lipids in pre-symptomatic and symptomatic animals. Our results demonstrate that there are significant alterations in HD rat hypothalamic protein expression such as glial fibrillary acidic protein (GFAP, heat shock protein-70, the oxidative damage protein glutathione peroxidase (Gpx4, glycogen synthase1 (Gys1 and the lipid synthesis enzyme acylglycerol-3-phosphate O-acyltransferase 1 (Agpat1. In addition, there are significant alterations in various circulating metabolic hormones and lipids in pre-symptomatic animals including, insulin, leptin, triglycerides and HDL, before any motor or cognitive alterations are apparent. These early metabolic and lipid alterations are likely prodromal signs of hypothalamic dysfunction. Gaining a greater understanding of the hypothalamic and metabolic alterations that occur in HD, could lead to the development of novel therapeutics for early interventional treatment of HD.

  17. Oxidative stress-induced proteome alterations target different cellular pathways in human myoblasts

    DEFF Research Database (Denmark)

    Baraibar, Martin A; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina;

    2011-01-01

    Although increased oxidative stress has been associated with the impairment of proliferation and function of adult human muscle stem cells, proteins either involved in the stress response or damaged by oxidation have not been identified. A parallel proteomics approach was performed for analyzing...... are mainly cytosolic and involved in carbohydrate metabolism, cellular assembly, cellular homeostasis, and protein synthesis and degradation. Pathway analysis revealed skeletal and muscular disorders, cell death, and cancer-related as the main molecular networks altered. Interestingly, these pathways...

  18. Functional and Morphological Adaptation to Peptidoglycan Precursor Alteration in Lactococcus lactis*

    OpenAIRE

    Deghorain, Marie; Fontaine, Laetitia; David, Blandine; Mainardi, Jean-Luc; Courtin, Pascal; Daniel, Richard; Errington, Jeff; Sorokin, Alexei; Bolotin, Alexander; Chapot-Chartier, Marie-Pierre; Hallet, Bernard; Hols, Pascal

    2010-01-01

    Cell wall peptidoglycan assembly is a tightly regulated process requiring the combined action of multienzyme complexes. In this study we provide direct evidence showing that substrate transformations occurring at the different stages of this process play a crucial role in the spatial and temporal coordination of the cell wall synthesis machinery. Peptidoglycan substrate alteration was investigated in the Gram-positive bacterium Lactococcus lactis by substituting the peptidoglycan precursor bi...

  19. Synthesis Organic Compound

    OpenAIRE

    Rasyid, Herlina; Firdaus; Hariani, Nunuk

    2015-01-01

    Abstract. Synthesis of metil ??-(p-hidroksifenil)akrilic from ??-(p-hidroksifenil)akrilat acid and methanol using Dean Stark Trap method had been done. Synthesis of ths compound intended to form the starting material in the subsequent synthesis of amide???s compound through the formation of ester compound. This synthesis using H2SO4 catalyst and Dean Stark Trap method, some of benzena which is added to remove the water that resulting from the reaction. Synthesis of this compound be held at re...

  20. Substructural controller synthesis

    Science.gov (United States)

    Su, Tzu-Jeng; Craig, Roy R., Jr.

    1989-01-01

    A decentralized design procedure which combines substructural synthesis, model reduction, decentralized controller design, subcontroller synthesis, and controller reduction is proposed for the control design of flexible structures. The structure to be controlled is decomposed into several substructures, which are modeled by component mode synthesis methods. For each substructure, a subcontroller is designed by using the linear quadratic optimal control theory. Then, a controller synthesis scheme called Substructural Controller Synthesis (SCS) is used to assemble the subcontrollers into a system controller, which is to be used to control the whole structure.

  1. Genetic alterations in pancreatic carcinoma

    Directory of Open Access Journals (Sweden)

    Schmid Roland M

    2003-01-01

    Full Text Available Abstract Cancer of the exocrine pancreas represents the fifth leading cause of cancer death in the Western population with an average survival after diagnosis of 3 to 6 months and a five-year survival rate under 5%. Our understanding of the molecular carcinogenesis has improved in the last few years due to the development of novel molecular biological techniques. Pancreatic cancer is a multi-stage process resulting from the accumulation of genetic changes in the somatic DNA of normal cells. In this article we describe major genetic alterations of pancreatic cancer, mutations in the proto-oncogene K-RAS and the tumor suppressors INK4A, TP53 and DPC4/SMAD4. The accumulation of these genetic changes leads to a profound disturbance in cell cycle regulation and continuous growth. The knowledge of the underlying molecular mechanisms will offer new therapeutic and diagnostic options and hopefully improve the outcome of this aggressive disease.

  2. Genetic alterations in pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Muhammad Wasif Saif; Lena Karapanagiotou; Kostas Syrigos

    2007-01-01

    The diagnosis of pancreatic cancer is devastating for patients and their relatives as the incidence rate is approximately the same as mortality rate. Only a small percentage, which ranges from 0.4% to 4% of patients who have been given this diagnosis, will be alive at five years. At the time of diagnosis, 80% of pancreatic cancer patients have unresectable or metastatic disease.Moreover, the therapeutic alternatives offered by chemotherapy or radiotherapy are few, if not zero. For all these reasons, there is an imperative need of analyzing and understanding the primitive lesions that lead to invasive pancreatic adenocarcinoma. Molecular pathology of these lesions is the key of our understanding of the mechanisms underlying the development of this cancer and will probably help us in earlier diagnosis and better therapeutic results. This review focuses on medical research on pancreatic cancer models and the underlying genetic alterations.

  3. Epigenetic alterations underlying autoimmune diseases.

    Science.gov (United States)

    Aslani, Saeed; Mahmoudi, Mahdi; Karami, Jafar; Jamshidi, Ahmad Reza; Malekshahi, Zahra; Nicknam, Mohammad Hossein

    2016-03-01

    Recent breakthroughs in genetic explorations have extended our understanding through discovery of genetic patterns subjected to autoimmune diseases (AID). Genetics, on the contrary, has not answered all the conundrums to describe a comprehensive explanation of causal mechanisms of disease etiopathology with regard to the function of environment, sex, or aging. The other side of the coin, epigenetics which is defined by gene manifestation modification without DNA sequence alteration, reportedly has come in to provide new insights towards disease apprehension through bridging the genetics and environmental factors. New investigations in genetic and environmental contributing factors for autoimmunity provide new explanation whereby the interactions between genetic elements and epigenetic modifications signed by environmental agents may be responsible for autoimmune disease initiation and perpetuation. It is aimed through this article to review recent progress attempting to reveal how epigenetics associates with the pathogenesis of autoimmune diseases. PMID:26761426

  4. DNA alterations photosensitized by tetracycline and some of its derivatives

    International Nuclear Information System (INIS)

    Bacteriophage M13 mp10 DNA were irradiated with near-UV light in the presence of tetracycline derivatives and primed with synthetic oligonucleotide to be used for DNA synthesis using Escherichia coli DNA polymerase. Chain terminations were observed by denaturing polyacrylamide gel electrophoresis and mapped precisely. All the synthesis stops occurred before or at the level of guanine residues, showing that the photoreaction mediated by tetracycline derivatives led to a preferential alteration of guanine residues. These lesions were demonstrated to be induced in DNA through a pathway involving singlet oxygen. Tetracycline derivatives also photoinduced the breakage of the DNA sugar-phosphate backbone monitored by the conversion of supercoiled phi X174 DNA to a relaxed form. This lesion was shown to be initiated by hydroxyl radicals. The production of this free radical has been confirmed by electron paramagnetic resonance (EPR) spin trapping experiments using 5,5-dimethyl-1-pyrroline-N-oxide as spin trap. In addition to the EPR signal due to OH radicals trapping another unassigned signal has been detected

  5. Optical tweezers reveal how proteins alter replication

    Science.gov (United States)

    Chaurasiya, Kathy

    Single molecule force spectroscopy is a powerful method that explores the DNA interaction properties of proteins involved in a wide range of fundamental biological processes such as DNA replication, transcription, and repair. We use optical tweezers to capture and stretch a single DNA molecule in the presence of proteins that bind DNA and alter its mechanical properties. We quantitatively characterize the DNA binding mechanisms of proteins in order to provide a detailed understanding of their function. In this work, we focus on proteins involved in replication of Escherichia coli (E. coli ), endogenous eukaryotic retrotransposons Ty3 and LINE-1, and human immunodeficiency virus (HIV). DNA polymerases replicate the entire genome of the cell, and bind both double-stranded DNA (dsDNA) and single-stranded DNA (ssDNA) during DNA replication. The replicative DNA polymerase in the widely-studied model system E. coli is the DNA polymerase III subunit alpha (DNA pol III alpha). We use optical tweezers to determine that UmuD, a protein that regulates bacterial mutagenesis through its interactions with DNA polymerases, specifically disrupts alpha binding to ssDNA. This suggests that UmuD removes alpha from its ssDNA template to allow DNA repair proteins access to the damaged DNA, and to facilitate exchange of the replicative polymerase for an error-prone translesion synthesis (TLS) polymerase that inserts nucleotides opposite the lesions, so that bacterial DNA replication may proceed. This work demonstrates a biophysical mechanism by which E. coli cells tolerate DNA damage. Retroviruses and retrotransposons reproduce by copying their RNA genome into the nuclear DNA of their eukaryotic hosts. Retroelements encode proteins called nucleic acid chaperones, which rearrange nucleic acid secondary structure and are therefore required for successful replication. The chaperone activity of these proteins requires strong binding affinity for both single- and double-stranded nucleic

  6. Survey On Speech Synthesis

    Directory of Open Access Journals (Sweden)

    A. Indumathi

    2012-12-01

    Full Text Available The primary goal of this paper is to provide an overview of existing Text-To-Speech (TTS Techniques by highlighting its usage and advantage. First Generation Techniques includes Formant Synthesis and Articulatory Synthesis. Formant Synthesis works by using individually controllable formant filters, which can be set to produce accurate estimations of the vocal-track transfer function. Articulatory Synthesis produces speech by direct modeling of Human articulator behavior. Second Generation Techniques incorporates Concatenative synthesis and Sinusoidal synthesis. Concatenative synthesis generates speech output by concatenating the segments of recorded speech. Generally, Concatenative synthesis generates the natural sounding synthesized speech. Sinusoidal Synthesis use a harmonic model and decompose each frame into a set of harmonics of an estimated fundamental frequency. The model parameters are the amplitudes and periods of the harmonics. With these, the value of the fundamental can be changed while keeping the same basic spectral..In adding, Third Generation includes Hidden Markov Model (HMM and Unit Selection Synthesis.HMM trains the parameter module and produce high quality Speech. Finally, Unit Selection operates by selecting the best sequence of units from a large speech database which matches the specification.

  7. Hindlimb unloading alters ligament healing

    Science.gov (United States)

    Provenzano, Paolo P.; Martinez, Daniel A.; Grindeland, Richard E.; Dwyer, Kelley W.; Turner, Joanne; Vailas, Arthur C.; Vanderby, Ray Jr

    2003-01-01

    We investigated the hypothesis that hindlimb unloading inhibits healing in fibrous connective tissue such as ligament. Male rats were assigned to 3- and 7-wk treatment groups with three subgroups each: sham control, ambulatory healing, and hindlimb-suspended healing. Ambulatory and suspended animals underwent surgical rupture of their medial collateral ligaments, whereas sham surgeries were performed on control animals. After 3 or 7 wk, mechanical and/or morphological properties were measured in ligament, muscle, and bone. During mechanical testing, most suspended ligaments failed in the scar region, indicating the greatest impairment was to ligament and not to bone-ligament insertion. Ligament testing revealed significant reductions in maximum force, ultimate stress, elastic modulus, and low-load properties in suspended animals. In addition, femoral mineral density, femoral strength, gastrocnemius mass, and tibialis anterior mass were significantly reduced. Microscopy revealed abnormal scar formation and cell distribution in suspended ligaments with extracellular matrix discontinuities and voids between misaligned, but well-formed, collagen fiber bundles. Hence, stress levels from ambulation appear unnecessary for formation of fiber bundles yet required for collagen to form structurally competent continuous fibers. Results support our hypothesis that hindlimb unloading impairs healing of fibrous connective tissue. In addition, this study provides compelling morphological evidence explaining the altered structure-function relationship in load-deprived healing connective tissue.

  8. Dolichol alters brain membrane functions

    International Nuclear Information System (INIS)

    It has been well demonstrated that there is a direct correlation between increase in dolichol level in brain and aging. An abnormally high level of dolichol was found in brain tissue of patients with pathological aging disorders. The aim of this study is to examine the physiological significance of dolichol affecting membrane transport activity and phospholipid acyl group turnover. Dolichol added to synaptic plasma membranes resulted in a biphasic effect on (Na+, K+)-ATPase, i.e., an enhancement of activity at low concentrations (5 μg/125 mg protein) and an inhibition of activity at high concentrations (40-100 μg). To probe the membrane acyl group turnover, the incorporation of [14C]-arachidonate into plasma membrane phospholipids was examined in the presence and absence of dolichol. Dolichol elicited an increase in the incorporation of label into phospholipids. However, the effects varied depending on whether BSA is present. In the absence of BSA, the increase in labeling of phosphatidylinositols is higher than that of phosphatidylcholines. These results suggest that dolichols, when inserted into membranes, may alter membrane functions

  9. Dolichol alters brain membrane functions

    Energy Technology Data Exchange (ETDEWEB)

    Sun, G.Y.; Sun, A.Y.; Schroeder, F.; Wood, G.; Strong, R.

    1986-03-05

    It has been well demonstrated that there is a direct correlation between increase in dolichol level in brain and aging. An abnormally high level of dolichol was found in brain tissue of patients with pathological aging disorders. The aim of this study is to examine the physiological significance of dolichol affecting membrane transport activity and phospholipid acyl group turnover. Dolichol added to synaptic plasma membranes resulted in a biphasic effect on (Na/sup +/, K/sup +/)-ATPase, i.e., an enhancement of activity at low concentrations (5 ..mu..g/125 mg protein) and an inhibition of activity at high concentrations (40-100 ..mu..g). To probe the membrane acyl group turnover, the incorporation of (/sup 14/C)-arachidonate into plasma membrane phospholipids was examined in the presence and absence of dolichol. Dolichol elicited an increase in the incorporation of label into phospholipids. However, the effects varied depending on whether BSA is present. In the absence of BSA, the increase in labeling of phosphatidylinositols is higher than that of phosphatidylcholines. These results suggest that dolichols, when inserted into membranes, may alter membrane functions.

  10. Protamine alterations in human spermatozoa.

    Science.gov (United States)

    Jodar, Meritxell; Oliva, Rafael

    2014-01-01

    Protamines are the major nuclear proteins in sperm cells, having a crucial role in the correct packaging of the paternal DNA. The fact that protamine haploinsufficiency in mice resulted in abnormal chromatin packaging and male infertility suggested that the protamines could also be important candidates in explaining some of the idiopathic male infertility cases in humans. The first clinical studies focused on analyzing protamines at the protein level. Various studies have found the presence of an altered amount of protamines in some infertile patients, in contrast to the normal situation in fertile individuals where the two protamines, protamine 1 and protamine 2, are both present in approximately equal quantities. Subsequently, the protamine genes were the subject of various mutational genetic screening studies in search of variants that could be associated with deregulation in the protamine expression observed. The results of these protamine mutational studies showed that the presence of high penetrant mutations is a very rare cause of male infertility. However, some variants and some haplotypes described may behave as risk factors for male infertility. More recently, the presence of RNA in the mature sperm cell has also been investigated. The present chapter will introduce the basic aspects of protamine evolution and function and review the various articles published to date on the relationship between the protamines studied at the DNA, RNA, and protein levels and male infertility. PMID:23955674

  11. Hyperglycaemia Alters Thymic Epithelial Cell Function

    Directory of Open Access Journals (Sweden)

    Vera Alexandrovna Abramova

    2013-07-01

    Full Text Available Insulin-dependent diabetes mellitus (IDDM is considered to be a consequence of unchecked auto-immune processes. Alterations in immune system responses are thought to be the cause of the disease, but the possibility that altered metabolite levels (glucose can establish the disease by specifically acting on and altering thymus stroma functions has not been investigated. Therefore, the direct effect of hyperglycaemia (HG on central tolerance mechanisms as a causative agent needs to be investigated.

  12. Influence of anabolic agents on protein synthesis and degradation in muscle cells grown in culture

    Energy Technology Data Exchange (ETDEWEB)

    Roeder, R.A.; Thorpe, S.D.; Byers, F.M.; Schelling, G.T.; Gunn, J.M.

    Muscle cell culture (L/sub 6/) studies were conducted to determine whether anabolic agents have a direct effect on the muscle cell. The effect of zeranol, testosterone propionate, estradiol benzoate, progesterone, dexamethasone and anabolic agent-dexamethasone combinations on protein synthesis and degradation were measured. Myoblast and myotube cultures were pretreated with 1 ..mu..M compounds for 12, 24 and 48 h before a 6-h synthesis or degradation measuring period. Protein synthesis was determined as cpm of (/sup 3/H) leucine incorporated per mg cell protein. Protein degradation was measured by a pulse-chase procedure using (/sup 3/H) leucine and expressed as the percentage labeled protein degraded in 6 h. Progesterone slightly increased protein synthesis in myoblast cultures. Testosterone propionate had no effect on synthesis. Protein synthesis was decreased by estradiol benzoate in myotube cultures. Protein degradation was not altered appreciably by anabolic agents. Protein synthesis was initially inhibited in myotubes by dexamethasone, but increased in myoblasts and myotubes in the extended incubation time. Dexamethasone also consistently increased protein degradation, but this required several hours to be expressed. Anabolic agents did not interfere with dexamethasone-induced increases in protein synthesis and degradation. The magnitude of response and sensitivity were similar for both the myoblast and the more fully differentiated myotube for all compounds tested. These results indicate that anabolic agents at the 1 ..mu..M level do not have a direct anabolic effect on muscle or alter glucocorticoid-induced catabolic response in muscle.

  13. Dolomite effect on borosilicate glass alteration

    International Nuclear Information System (INIS)

    Highlights: ► Dolomite is a common mineral of clayey formations considered for radioactive waste disposals. ► Borosilicate glass/dolomite interaction have been studied by batch tests and solid analysis. ► Mg provided by dolomite combines with Si from glass to yield secondary Mg–silicates. ► This precipitation increases glass alteration, though in a moderate manner. ► Geochemical modeling allows to quantify the alteration mechanisms involved. - Abstract: Dolomite (CaMg(CO3)2) is one of the common rock-forming minerals in many geological media, in particular in clayey layers that are currently considered as potential host formations for a deep radioactive waste disposal facility. Magnesium in solution is one of the elements known to potentially enhance the alteration of nuclear glasses. The alteration of borosilicate glasses with dolomite as a Mg-bearing mineral source was investigated for 8 months in batch tests at 90 °C. Glass composition effects were investigated through two compositions (SiBNaAlCaZrO and SiBNaAlZrO) differing in their Ca content. The Ca-rich glass alteration is slightly enhanced in the presence of dolomite compared to the alteration observed in pure water. This greater alteration is explained by the precipitation of Mg silicate phases on the dolomite and glass surfaces. In contrast, the Ca-free glass alteration decreases in the presence of dolomite compared to the alteration observed in pure water. This behavior is explained by Ca incorporation in the amorphous layer (formed during glass alteration) coming from dolomite dissolution. Calcium acts as a layer reorganizer and limits glass alteration by reducing the diffusion of reactive species through the altered layer. Modeling was performed using the GRAAL model implemented within the CHESS/HYTEC geochemical code to discriminate and interpret the mechanisms involved in glass/dolomite interactions. Magnesium released by dolomite dissolution reacts with silica provided by glass

  14. A kernel version of multivariate alteration detection

    DEFF Research Database (Denmark)

    Nielsen, Allan Aasbjerg; Vestergaard, Jacob Schack

    2013-01-01

    Based on the established methods kernel canonical correlation analysis and multivariate alteration detection we introduce a kernel version of multivariate alteration detection. A case study with SPOT HRV data shows that the kMAD variates focus on extreme change observations....

  15. Altered States of Consciousness and Alcohol.

    Science.gov (United States)

    Jones, Ben Morgan; And Others

    This document contains the reports of research at a symposium on "Altered States of Consciousness and Alcohol." The participants primarily agreed that alcohol induces an altered state of consciousness similar to other drugs, but that this phenomenon has not been explicitly stated due to the current interest in newer and more novel drugs. The…

  16. Changes in CRH and ACTH Synthesis during Experimental and Human Septic Shock

    OpenAIRE

    Andrea Polito; Romain Sonneville; Céline Guidoux; Lucinda Barrett; Odile Viltart; Virginie Mattot; Shidasp Siami; Geoffroy Lorin de la Grandmaison; Fabrice Chrétien; Mervyn Singer; Françoise Gray; Djillali Annane; Jean-Philippe Brouland; Tarek Sharshar

    2011-01-01

    CONTEXT: The mechanisms of septic shock-associated adrenal insufficiency remain unclear. This study aimed at investigating the synthesis of corticotropin-releasing hormone (CRH) and vasopressin (AVP) by parvocellular neurons and the antehypophyseal expression of ACTH in human septic shock and in an experimental model of sepsis. OBJECTIVE: To test the hypothesis that ACTH secretion is decreased secondarily to alteration of CRH or AVP synthesis, we undertook a neuropathological study of the ant...

  17. Long-term alteration of cementitious materials

    International Nuclear Information System (INIS)

    Long-term alteration of cementitious materials in the geological condition has been discussed for the safety assessment of radioactive waste disposal. This paper describes the status of understanding long-term chemical alteration of cement, by reviewing some of our investigations on this issue in which we developed a thermodynamic incongruent C-S-H dissolution/precipitation model and a reactive transport calculation code. Alteration of C-S-H gel in a saline groundwater and the change of chemical barrier performance of cementitious materials due to the alteration are also discussed. Some key issues to be discussed further are given and suggested for the future studies on the long-term alteration of cementitious materials in the repository environment. (author)

  18. The opposite effect of a 5-HT1B receptor agonist on 5-HT synthesis, as well as its resistant counterpart, in an animal model of depression

    OpenAIRE

    Skelin, Ivan; Kovačević, Tomislav; Sato, Hiroki; Diksic, Mirko

    2012-01-01

    Flinders Sensitive Line (FSL) rat is as an animal model of depression with altered parameters of the serotonergic (5-HT) system function (5-HT synthesis rates, tissue concentrations, release, receptor density and affinity), as well as an altered sensitivity of these parameters to different 5-HT based antidepressants. The effects of acute and chronic treatments with the 5-HT1B agonist, CP-94253 on 5-HT synthesis, in the FSL rats and the Flinders Resistant Line (FRL) controls were measured usin...

  19. Aqueous Alteration on Mars. Chapter 23

    Science.gov (United States)

    Ming, Douglas W.; Morris, Richard V.; Clark, Benton C.

    2007-01-01

    Aqueous alteration is the change in composition of a rock, produced in response to interactions with H2O-bearing ices, liquids, and vapors by chemical weathering. A variety of mineralogical and geochemical indicators for aqueous alteration on Mars have been identified by a combination of surface and orbital robotic missions, telescopic observations, characterization of Martian meteorites, and laboratory and terrestrial analog studies. Mineralogical indicators for aqueous alteration include goethite (lander), jarosite (lander), kieserite (orbiter), gypsum (orbiter) and other Fe-, Mg-, and Ca-sulfates (landers), halides (meteorites, lander), phyllosilicates (orbiter, meteorites), hematite and nanophase iron oxides (telescopic, orbiter, lander), and Fe-, Mg-, and Ca-carbonates (meteorites). Geochemical indicators (landers only) for aqueous alteration include Mg-, Ca-, and Fe-sulfates, halides, and secondary aluminosilicates such as smectite. Based upon these indicators, several styles of aqueous alteration have been suggested on Mars. Acid-sulfate weathering (e.g., formation of jarosite, gypsum, hematite, and goethite), may occur during (1) the oxidative weathering of ultramafic igneous rocks containing sulfides, (2) sulfuric acid weathering of basaltic materials, and (3) acid fog (i.e., vapors rich in H2SO4) weathering of basaltic or basaltic-derived materials. Near-neutral or alkaline alteration occurs when solutions with pH near or above 7 move through basaltic materials and form phases such as phyllosilicates and carbonates. Very low water:rock ratios appear to have been prominent at most of the sites visited by landed missions because there is very little alteration (leaching) of the original basaltic composition (i.e., the alteration is isochemical or in a closed hydrologic system). Most of the aqueous alteration appears to have occurred early in the history of the planet (3 to 4.5 billion years ago); however, minor aqueous alteration may be occurring at the

  20. Synthesis of Pandamarilactone-1

    OpenAIRE

    Seah, Kang Yee; Macnaughton, Sarah J.; Dallimore, Jonathan W. P.; Robertson, Jeremy

    2014-01-01

    The first total synthesis of pandamarilactone-1, an alkaloid of Pandanus amaryllifolius, is reported. The nine-step synthesis features furan oxidation with singlet oxygen and then spiro-N,O-acetalization and elimination to generate the natural product and further Pandanus alkaloids, pandamarilactonines A–D.

  1. Total Synthesis of (-)-Cardiopetaline.

    Science.gov (United States)

    Nishiyama, Yoshitake; Yokoshima, Satoshi; Fukuyama, Tohru

    2016-05-20

    The total synthesis of (-)-cardiopetaline, an aconitine-type natural product, has been accomplished. Our synthesis involved a Wagner-Meerwein rearrangement of a sulfonyloxirane that enabled, in a single step, the construction of the bicyclo[3.2.1] system in the aconitine skeleton and effective introduction of oxygen functional groups at the appropriate positions. PMID:27166640

  2. Synthesis of oligonucleotide phosphorodithioates

    DEFF Research Database (Denmark)

    Beaton, G.; Brill, W. K D; Grandas, A.;

    1991-01-01

    The synthesis of DNA containing sulfur at the two nonbonding internucleotide valencies is reported. Several different routes using either tervalent or pentavalent mononucleotide synthons are described. © 1991.......The synthesis of DNA containing sulfur at the two nonbonding internucleotide valencies is reported. Several different routes using either tervalent or pentavalent mononucleotide synthons are described. © 1991....

  3. Synthesis of Mechanisms

    DEFF Research Database (Denmark)

    Hansen, John Michael

    1999-01-01

    These notes describe an automated procedure for analysis and synthesis of mechanisms. The analysis method is based on the body coordinate formulation, and the synthesis is based on applying optimization methods, used to minimize the difference between an actual and a desired behaviour...

  4. Synthesis of Isoiminosugars

    DEFF Research Database (Denmark)

    Hyldtoft, Lene; Godskesen, Michael Anders; Lundt, Inge

    1998-01-01

    A short synthesis of isoiminosugars have been developed. Bromolactones are diastereoselectively alkylated at C-2 followed by ring closure to the corresponding lactams. Reduction of these then gives isoiminosugars......A short synthesis of isoiminosugars have been developed. Bromolactones are diastereoselectively alkylated at C-2 followed by ring closure to the corresponding lactams. Reduction of these then gives isoiminosugars...

  5. Neural protein synthesis during aging: effects on plasticity and memory

    Directory of Open Access Journals (Sweden)

    Lesley A Schimanski

    2010-08-01

    Full Text Available During aging, many experience a decline in cognitive function that includes memory loss. The encoding of long-term memories depends on new protein synthesis, and this is also reduced during aging. Thus, it is possible that changes in the regulation of protein synthesis contribute to the memory impairments observed in older animals. Several lines of evidence support this hypothesis. For instance, protein synthesis is required for a longer period following learning to establish long-term memory in aged rodents. Also, under some conditions, synaptic activity or pharmacological activation can induce de novo protein synthesis and lasting changes in synaptic transmission in aged, but not young, rodents; the opposite results can be observed in other conditions. These changes in plasticity likely play a role in manifesting the altered place field properties observed in awake and behaving aged rats. Thus, the collective evidence suggests a link between memory loss and the regulation of protein synthesis in senescence. In fact, pharmaceuticals that target the signaling pathways required for induction of protein synthesis have been shown to improve memory, synaptic plasticity, and place cell properties in aged animals. We suggest that a better understanding of the mechanisms that lead to different protein expression patterns in the neural circuits that change as a function of age will enable the development of more effective therapeutic treatments for memory loss.

  6. Synthesis of zeolite membranes

    Institute of Scientific and Technical Information of China (English)

    JIANG Haiyang; ZHANG Baoquan; Y. S. Lin; LI Yongdan

    2004-01-01

    Zeolite membranes offer great application potentials in membrane separation and/or reaction due to their excellent separation performance and catalytic ability. Up to present, various synthesis methods of zeolite membranes have been developed, including embedded method,in-situ hydrothermal synthesis method, and secondary growth method etc. Compared with the in-situ hydrothermal synthesis method, the secondary growth method possesses a variety of advantages such as easier operation, higher controllability in crystal orientation, microstructure and film thickness, leading to much better reproducibility. This review provides a concise summary and analysis of various synthesis methods reported in the literature. In particular, the secondary growth method was discussed in detail in terms of crystal orientation, defects and crystal grain layers. Some critical issues were also highlighted, which were conducive to the improvement in the synthesis technology of zeolite membranes.

  7. VHDL for logic synthesis

    CERN Document Server

    Rushton, Andrew

    2011-01-01

    Many engineers encountering VHDL (very high speed integrated circuits hardware description language) for the first time can feel overwhelmed by it. This book bridges the gap between the VHDL language and the hardware that results from logic synthesis with clear organisation, progressing from the basics of combinational logic, types, and operators; through special structures such as tristate buses, register banks and memories, to advanced themes such as developing your own packages, writing test benches and using the full range of synthesis types. This third edition has been substantially rewritten to include the new VHDL-2008 features that enable synthesis of fixed-point and floating-point hardware. Extensively updated throughout to reflect modern logic synthesis usage, it also contains a complete case study to demonstrate the updated features. Features to this edition include: * a common VHDL subset which will work across a range of different synthesis systems, targeting a very wide range of technologies...

  8. A Propensity for n-omega-Amino Acids in Thermally-Altered Antarctic Meteorites

    Science.gov (United States)

    Burton, Aaron S.; Elsila, Jamie E.; Callahan, Michael P.; Martin, Mildred G.; Glavin, Daniel P.; Johnson, Natasha M.; Dworkin, Jason P.

    2012-01-01

    Carbonaceous meteorites are known to contain a wealth of indigenous organic molecules, including amino acids, which suggests that these meteorites could have been an important source of prebiotic organic material during the origins of life on Earth and possibly elsewhere. We report the detection of extraterrestrial amino acids in thermally-altered type 3 CV and CO carbonaceous chondrites and ureilites recovered from Antarctica. The amino acid concentrations of the thirteen Antarctic meteorites were generally less abundant than in more amino acid-rich CI, CM, and CR carbonaceous chondrites that experienced much lower temperature aqueous alteration on their parent bodies. In contrast to low-temperature aqueously-altered meteorites that show complete structural diversity in amino acids formed predominantly by Strecker-cyanohydrin synthesis, the thermally-altered meteorites studied here are dominated by small, straight-chain, amine terminal (n-omega-amino) amino acids that are not consistent with Strecker formation. The carbon isotopic ratios of two extraterrestrial n-omega-amino acids measured in one of the CV chondrites are consistent with C-13-depletions observed previously in hydrocarbons produced by Fischer-Tropsch type reactions. The predominance of n-omega-amino acid isomers in thermally-altered meteorites hints at cosmochemical mechanisms for the preferential formation and preservation of a small subset of the possible amino acids.

  9. Cyclin B synthesis and rapamycin-sensitive regulation of protein synthesis during starfish oocyte meiotic divisions.

    Science.gov (United States)

    Lapasset, Laure; Pradet-Balade, Bérengère; Vergé, Valérie; Lozano, Jean-Claude; Oulhen, Nathalie; Cormier, Patrick; Peaucellier, Gérard

    2008-11-01

    Translation of cyclin mRNAs represents an important event for proper meiotic maturation and post-fertilization mitoses in many species. Translational control of cyclin B mRNA has been described to be achieved through two separate but related mechanisms: translational repression and polyadenylation. In this paper, we evaluated the contribution of global translational regulation by the cap-dependent translation repressor 4E-BP (eukaryotic initiation factor 4E-binding protein) on the cyclin B protein synthesis during meiotic maturation of the starfish oocytes. We used the immunosupressant drug rapamycin, a strong inhibitor of cap-dependent translation, to check for the involvement of this protein synthesis during this physiological process. Rapamycin was found to prevent dissociation of 4E-BP from the initiation factor eIF4E and to suppress correlatively a burst of global protein synthesis occurring at the G2/M transition. The drug had no effect on first meiotic division but defects in meiotic spindle formation prevented second polar body emission, demonstrating that a rapamycin-sensitive pathway is involved in this mechanism. While rapamycin affected the global protein synthesis, the drug altered neither the specific translation of cyclin B mRNA nor the expression of the Mos protein. The expression of these two proteins was correlated with the phosphorylation and the dissociation of the cytoplasmic polyadenylation element-binding protein from eIF4E. PMID:18361417

  10. Organotemplate-free Hydrothermal Synthesis of SUZ-4 Zeolite:Influence of Synthesis Conditions

    Institute of Scientific and Technical Information of China (English)

    周华兰; 吴雅静; 张伟; 王军

    2014-01-01

    Various conditions were investigated in detail for the novel organic template-free static hydrothermal synthesis of SUZ-4 zeolite in the presence of seeds. The obtained samples were characterized by XRD (X-ray dif-fraction), SEM (scanning electron microscope), TG (thermal gravimetric analysis), ICP (inductively coupling plasma) elemental analysis, nitrogen sorption isotherm and surface area. The results show that pure SUZ-4 zeolites with high crystallinity are obtained in a broad window of synthesis conditions:seed mass concentration 0.2%-2%, SiO2/Al2O3 molar ratio 21-25, KOH/SiO2 molar ratio 0.33-0.43, H2O/SiO2 molar ratio 7.14-38.1, aging time 24 h, crystallization temperature 160 °C, and crystallization time 6-10 d. Also, crystallinity and size of the rod-like SUZ-4 zeolite crystals are found to alter with the conditions.

  11. Hydrothermal Routes for the Synthesis of CdSe Core Quantum Dots

    OpenAIRE

    Schneider, Raphaël; Balan, Lavinia

    2012-01-01

    The synthesis of QDs in aqueous solution is still pursued in hopes of providing a material that is easily fabricated and functionalized. During many years, the synthesis of CdSe in aqueous media has been investigated with limited success due to the low quantum yields and poor crystallinity of the nanoparticles produced. Moreover, the fluorescence of the CdSe QDs obtained by this approach cannot be controlled over a wide range. Direct synthesis of CdSe QDs in water is however a promising alter...

  12. Leptin Modulates Norepinephrine-Mediated Melatonin Synthesis in Cultured Rat Pineal Gland

    OpenAIRE

    Rodrigo Antonio Peliciari-Garcia; Jéssica Andrade-Silva; José Cipolla-Neto; Carla Roberta de Oliveira Carvalho

    2013-01-01

    Pineal melatonin synthesis can be modulated by many peptides, including insulin. Because melatonin appears to alter leptin synthesis, in this work we aimed to investigate whether leptin would have a role on norepinephrine- (NE-)mediated melatonin synthesis in cultured rat pineal glands. According to our data, cultured rat pineal glands express leptin receptor isoform b (Ob-Rb). Pineal expression of Ob-Rb mRNA was also observed in vivo. Administration of leptin (1 nM) associated with NE (1 µM)...

  13. Systematic Review and Meta-Analysis on Incidence of Altered Sensation of Mandibular Implant Surgery.

    Science.gov (United States)

    Lin, Chia-Shu; Wu, Shih-Yun; Huang, Hsin-Yi; Lai, Yu-Lin

    2016-01-01

    Altered sensation (including paresthesia, dysesthesia and hypoesthesia) after mandibular implant surgery may indicate transient or permanent injury of the inferior alveolar nerve and the mental branch, and considerably lower patients' satisfaction about the therapy. Previous studies have shown a great degree of variability on the incidence of altered sensation. We here reported the incidence of altered sensation after mandibular implant surgery based on a meta-analysis of 26 articles published between 1990.1.1 and 2016.1.1. Study quality and risk of bias was assessed and the studies with a lower score were excluded in the meta-analysis. Data synthesis was performed using the logistic-normal random-effect model. The meta-analyses revealed that the short-term (10 days after implant placement) and long-term (1 year after implant placement) incidence was 13% (95% CI, 6%-25%) and 3% (95% CI, 1%-7%), respectively. (2) For the patients who initially reported altered sensation, 80% (95% CI, 52%-94%) of them would return to normal sensation within 6 months after surgery, and 91% (95% CI, 78%-96%) of them would return to normal sensation one year after surgery. We concluded that dentist-patient communication about the risk of altered sensation is critical to treatment planning, since the short-term incidence of altered sensation is substantial (13%). When a patient reports altered sensation, regular assessment for 6 months would help tracing the changes of symptoms. In terms of long-term follow-up (1 year after surgery), the incidence is much lower (3%) and most patients (91%) would return to normal sensation. PMID:27100832

  14. Systematic Review and Meta-Analysis on Incidence of Altered Sensation of Mandibular Implant Surgery

    Science.gov (United States)

    Lin, Chia-Shu; Wu, Shih-Yun; Huang, Hsin-Yi; Lai, Yu-Lin

    2016-01-01

    Altered sensation (including paresthesia, dysesthesia and hypoesthesia) after mandibular implant surgery may indicate transient or permanent injury of the inferior alveolar nerve and the mental branch, and considerably lower patients’ satisfaction about the therapy. Previous studies have shown a great degree of variability on the incidence of altered sensation. We here reported the incidence of altered sensation after mandibular implant surgery based on a meta-analysis of 26 articles published between 1990.1.1 and 2016.1.1. Study quality and risk of bias was assessed and the studies with a lower score were excluded in the meta-analysis. Data synthesis was performed using the logistic-normal random-effect model. The meta-analyses revealed that the short-term (10 days after implant placement) and long-term (1 year after implant placement) incidence was 13% (95% CI, 6%-25%) and 3% (95% CI, 1%-7%), respectively. (2) For the patients who initially reported altered sensation, 80% (95% CI, 52%-94%) of them would return to normal sensation within 6 months after surgery, and 91% (95% CI, 78%-96%) of them would return to normal sensation one year after surgery. We concluded that dentist-patient communication about the risk of altered sensation is critical to treatment planning, since the short-term incidence of altered sensation is substantial (13%). When a patient reports altered sensation, regular assessment for 6 months would help tracing the changes of symptoms. In terms of long-term follow-up (1 year after surgery), the incidence is much lower (3%) and most patients (91%) would return to normal sensation. PMID:27100832

  15. Altering Flashlamp Output for Realistic Solar Simulation

    Science.gov (United States)

    Mueller, R. L.; Seaman, C. H.

    1985-01-01

    Commercial glass optical filter corrects spectrum of xenon flashtubes used to test photovoltaic solar cells. Filter withstands thousands of flashes without perceptible alteration of passband characteristics. With filter, calibration errors reduced to less than 1 percent.

  16. Borosilicate glass alteration driven by magnesium carbonates

    International Nuclear Information System (INIS)

    Highlights: ► We studied borosilicate glass/hydromagnesite interaction. ► Magnesium silicate precipitation increases glass alteration. ► Geochemical modeling allows to quantify the alteration mechanisms involved. - Abstract: The alteration of simplified synthetic glass, representative of the French reference nuclear glass R7T7, in presence of hydromagnesite has been experimentally investigated and modeled. Magnesium in solution is known to potentially enhance glass alteration; nuclear glass clayed host rocks contain magnesium and can dissolve to maintain the concentration of magnesium in solution. For modeling purposes, it was suitable to study a simple system. Hydromagnesite was therefore chosen as a simple model mineral in order to check the influence of an Mg-rich mineral on glass alteration. Since the models use thermodynamic and kinetic parameters measured in pure water and pH-buffered solutions, changing the solution composition or adding minerals is a key step towards the validation of the modeling assumptions before using the model for predictive purposes. Experiments revealed that glass alteration is enhanced in presence of hydromagnesite. Modeling was performed using the GRAAL model implemented within the CHESS/HYTEC reactive transport code. Modeling proved useful both for explaining the mechanisms involved and quantifying the impact on glass alteration: Mg coming from hydromagnesite dissolution reacts with Si provided by the glass in order to form magnesium silicates. This reaction decreases the pH down to neutral conditions where magnesium silicates are more soluble than at the natural alkali pH imposed by glass or hydromagnesite dissolution. The driving force of the magnesium silicate precipitation is eventually the interdiffusion of alkali within the altered amorphous glass layer as this mechanism consumes protons. The model’s ability to describe the concentrations of elements in solution and formed solids whatever the glass

  17. Diabetes and mitochondrial bioenergetics: Alterations with age

    OpenAIRE

    Ferreira, Fernanda M.; Palmeira, Carlos M.; Seiça, Raquel; Moreno, António J.; Santos, Maria S.

    2003-01-01

    Several studies have been carried out to evaluate the alterations in mitochondrial functions of diabetic rats. However, some of the results reported are controversial, since experimental conditions, such as aging, and/or strain of animals used were different. The purpose of this study was to evaluate the metabolic changes in liver mitochondria, both in the presence of severe hyperglycaemia (STZ-treated rats) and mild hyperglycaemia (Goto-Kakizaki (GK) rats). Moreover, metabolic alterations we...

  18. Total Synthesis of Teixobactin.

    Science.gov (United States)

    Giltrap, Andrew M; Dowman, Luke J; Nagalingam, Gayathri; Ochoa, Jessica L; Linington, Roger G; Britton, Warwick J; Payne, Richard J

    2016-06-01

    The first total synthesis of the cyclic depsipeptide natural product teixobactin is described. Synthesis was achieved by solid-phase peptide synthesis, incorporating the unusual l-allo-enduracididine as a suitably protected synthetic cassette and employing a key on-resin esterification and solution-phase macrolactamization. The synthetic natural product was shown to possess potent antibacterial activity against a range of Gram-positive pathogenic bacteria, including a virulent strain of Mycobacterium tuberculosis and methicillin-resistant Staphylococcus aureus (MRSA). PMID:27191730

  19. Asymmetric synthesis v.4

    CERN Document Server

    Morrison, James

    1984-01-01

    Asymmetric Synthesis, Volume 4: The Chiral Carbon Pool and Chiral Sulfur, Nitrogen, Phosphorus, and Silicon Centers describes the practical methods of obtaining chiral fragments. Divided into five chapters, this book specifically examines initial chiral transmission and extension. The opening chapter describes the so-called chiral carbon pool, the readily available chiral carbon fragments used as building blocks in synthesis. This chapter also provides a list of 375 chiral building blocks, along with their commercial sources, approximate prices, and methods of synthesis. Schemes involving

  20. Gas Phase Nanoparticle Synthesis

    Science.gov (United States)

    Granqvist, Claes; Kish, Laszlo; Marlow, William

    This book deals with gas-phase nanoparticle synthesis and is intended for researchers and research students in nanomaterials science and engineering, condensed matter physics and chemistry, and aerosol science. Gas-phase nanoparticle synthesis is instrumental to nanotechnology - a field in current focus that raises hopes for environmentally benign, resource-lean manufacturing. Nanoparticles can be produced by many physical, chemical, and even biological routes. Gas-phase synthesis is particularly interesting since one can achieve accurate manufacturing control and hence industrial viability.

  1. Synthesis of Chiral Cyclopentenones.

    Science.gov (United States)

    Simeonov, Svilen P; Nunes, João P M; Guerra, Krassimira; Kurteva, Vanya B; Afonso, Carlos A M

    2016-05-25

    The cyclopentenone unit is a very powerful synthon for the synthesis of a variety of bioactive target molecules. This is due to the broad diversity of chemical modifications available for the enone structural motif. In particular, chiral cyclopentenones are important precursors in the asymmetric synthesis of target chiral molecules. This Review provides an overview of reported methods for enantioselective and asymmetric syntheses of cyclopentenones, including chemical and enzymatic resolution, asymmetric synthesis via Pauson-Khand reaction, Nazarov cyclization and organocatalyzed reactions, asymmetric functionalization of the existing cyclopentenone unit, and functionalization of chiral building blocks. PMID:27101336

  2. Sleep Deprivation Alters Choice Strategy Without Altering Uncertainty or Loss Aversion Preferences

    Directory of Open Access Journals (Sweden)

    O'Dhaniel A Mullette-Gillman

    2015-10-01

    Full Text Available Sleep deprivation alters decision making; however, it is unclear what specific cognitive processes are modified to drive altered choices. In this manuscript, we examined how one night of total sleep deprivation (TSD alters economic decision making. We specifically examined changes in uncertainty preferences dissociably from changes in the strategy with which participants engage with presented choice information. With high test-retest reliability, we show that TSD does not alter uncertainty preferences or loss aversion. Rather, TSD alters the information the participants rely upon to make their choices. Utilizing a choice strategy metric which contrasts the influence of maximizing and satisficing information on choice behavior, we find that TSD alters the relative reliance on maximizing information and satisficing information, in the gains domain. This alteration is the result of participants both decreasing their reliance on cognitively-complex maximizing information and a concomitant increase in the use of readily-available satisficing information. TSD did not result in a decrease in overall information use in either domain. These results show that sleep deprivation alters decision making by altering the informational strategies that participants employ, without altering their preferences.

  3. Selective carboxyl methylation of structurally altered calmodulins in Xenopus oocytes

    International Nuclear Information System (INIS)

    The eucaryotic protein carboxyl methyltransferase specifically modifies atypical D-aspartyl and L-isoaspartyl residues which are generated spontaneously as proteins age. The selectivity of the enzyme for altered proteins in intact cells was explored by co-injecting Xenopus laevis oocytes with S-adenosyl-L-[methyl-3H]methionine and structurally altered calmodulins generated during a 14-day preincubation in vitro. Control experiments indicated that the oocyte protein carboxyl methyltransferase was not saturated with endogenous substrates, since protein carboxyl methylation rates could be stimulated up to 8-fold by increasing concentrations of injected calmodulin. The oocyte protein carboxyl methyltransferase showed strong selectivities for bovine brain and bacterially synthesized calmodulins which had been preincubated in the presence of 1 mM EDTA relative to calmodulins which had been preincubated with 1 mM CaCl2. Radioactive methyl groups were incorporated into base-stable linkages with recombinant calmodulin as well as into carboxyl methyl esters following its microinjection into oocytes. This base-stable radioactivity most likely represents the trimethylation of lysine 115, a highly conserved post-translational modification which is present in bovine and Xenopus but not in bacterially synthesized calmodulin. Endogenous oocyte calmodulin incorporates radioactivity into both carboxyl methyl esters and into base-stable linkages following microinjection of oocytes with S-adenosyl-[methyl-3H]methionine alone. The rate of oocyte calmodulin carboxyl methylation in injected oocytes is calculated to be similar to that of lysine 115 trimethylation, suggesting that the rate of calmodulin carboxyl methylation is similar to that of calmodulin synthesis. At steady state, oocyte calmodulin contains approximately 0.0002 esters/mol of protein, which turn over rapidly

  4. Locomotion in Lymphocytes is Altered by Differential PKC Isoform Expression

    Science.gov (United States)

    Sundaresan, A.; Risin, D.; Pellis, N. R.

    1999-01-01

    Lymphocyte locomotion is critical for proper elicitation of the immune response. Locomotion of immune cells via the interstitium is essential for optimal immune function during wound healing, inflammation and infection. There are conditions which alter lymphocyte locomotion and one of them is spaceflight. Lymphocyte locomotion is severely inhibited in true spaceflight (true microgravity) and in rotating wall vessel culture (modeled microgravity). When lymphocytes are activated prior to culture in modeled microgravity, locomotion is not inhibited and the levels are comparable to those of static cultured lymphocytes. When a phorbol ester (PMA) is used in modeled microgravity, lymphocyte locomotion is restored by 87%. This occurs regardless if PMA is added after culture in the rotating wall vessel or during culture. Inhibition of DNA synthesis also does not alter restoration of lymphocyte locomotion by PMA. PMA is a direct activator of (protein kinase C) PKC . When a calcium ionophore, ionomycin is used it does not possess any restorative properties towards locomotion either alone or collectively with PMA. Since PMA brings about restoration without help from calcium ionophores (ionomycin), it is infer-red that calcium independent PKC isoforms are involved. Changes were perceived in the protein levels of PKC 6 where levels of the protein were downregulated at 24,72 and 96 hours in untreated rotated cultures (modeled microgravity) compared to untreated static (1g) cultures. At 48 hours there is an increase in the levels of PKC & in the same experimental set up. Studies on transcriptional and translational patterns of calcium independent isoforms of PKC such as 8 and E are presented in this study.

  5. Alteration features in natural zirconolite from carbonatites

    International Nuclear Information System (INIS)

    In nature, zirconolite occurs as an accessory mineral in many different rock types, but the majority of reported occurrences are from carbonatites (magmatic carbonates) of geological age varying from a few million years to 2 billion years old. Within these 19 carbonatite occurrences, of which 15 have been studied in some detail, zirconolite displays varying degrees of alteration in six samples. This alteration ranges from incipient minor effects to major corrosion, recrystallization and complete replacement by secondary phases. The degree of alteration broadly correlates with either the age, or actinide content of the zirconolite (or both), and thus the extent and degree of metamictization. Changes in zirconolite composition with alteration include an increase in hydration (H2O), Si, Ba and Pb (possibly radiogenic in origin), and a decrease primarily in Ca and Fe. Th can be remobilized, and of the rare earth elements (REE), there is evidence that the heavy-REE are mobilized more readily than the light-REE. Using backscattered electron images and electron microprobe analyses, this study documents and illustrates the range of alteration features observed in zirconolite from several carbonatites, in terms of both compositional and textural changes, and provides some physico-chemical information on the fluids responsible for the alteration. Copyright (2001) Material Research Society

  6. Chronic hyperammonemia, glutamatergic neurotransmission and neurological alterations.

    Science.gov (United States)

    Llansola, Marta; Montoliu, Carmina; Cauli, Omar; Hernández-Rabaza, Vicente; Agustí, Ana; Cabrera-Pastor, Andrea; Giménez-Garzó, Carla; González-Usano, Alba; Felipo, Vicente

    2013-06-01

    This mini-review focus on our studies on alterations in glutamatergic neurotransmission and their role in neurological alterations in rat models of chronic hyperammonemia and hepatic encephalopathy (HE). Hyperammonemia impairs the glutamate-nitric oxide (NO)-cGMP pathway in cerebellum, which is responsible for reduced learning ability. We studied the underlying mechanisms and designed treatments to restore the pathway and learning. This was achieved by treatment with: phosphodiesterase 5 inhibitors, cGMP, anti-inflammatories (ibuprofen), p38 inhibitors or GABAA receptor antagonists (bicuculline). Hyperammonemia alters signal transduction associated to metabotropic glutamate receptors (mGluRs). Hypokinesia in hyperammonemia and HE is due to increased extracellular glutamate and mGluR1 activation in substantia nigra; blocking this receptor restores motor activity. The motor responses to mGluRs activation in nucleus accumbens (NAcc) are altered in hyperammonemia and HE, with reduced dopamine and increased glutamate release. This leads to activation of different neuronal circuits and enhanced motor responses. These studies show that altered responses to activation of NMDA receptors and mGluRs play essential roles in cognitive and motor alterations in hyperammonemia and HE and provide new treatments restoring cognitive and motor function. PMID:23010935

  7. Quantitative relationship between hepatocytic neoplasms and islands of cellular alteration during hepatocarcinogenesis in the male F344 rat.

    OpenAIRE

    Kaufmann, W. K.; Mackenzie, S. A.; Kaufman, D G

    1985-01-01

    Hepatocytic neoplasms (nodules and carcinomas) and islands of cellular alteration which display abnormal retention of glycogen on fasting were quantified in F344 male rats at intervals after initiation of hepatocarcinogenesis by the combination of a two-thirds partial hepatectomy with a single treatment with methyl(acetoxymethyl)-nitrosamine during the subsequent peak of DNA synthesis in regenerating livers. In initiated rats fed the liver tumor promoter phenobarbital, yields of neoplasms and...

  8. Mutation in the myelin proteolipid protein gene alters BK and SK channel function in the caudal medulla

    OpenAIRE

    Mayer, Catherine A.; Macklin, Wendy B.; Avishai, Nanthawan; Balan, Kannan; Wilson, Christopher G.; Miller, Martha J.

    2009-01-01

    Proteolipid protein (Plp) gene mutation in rodents causes severe CNS dysmyelination, early death, and lethal hypoxic ventilatory depression (Miller et al. 2004). To determine if Plp mutation alters neuronal function critical for control of breathing, the nucleus tractus solitarii (nTS) of four rodent strains were studied: myelin deficient rats (MD), myelin synthesis deficient (Plpmsd), and Plpnull mice, as well as shiverer (Mbpshi) mice, a myelin basic protein mutant. Current-voltage relation...

  9. Two-directional synthesis as a tool for diversity-oriented synthesis: Synthesis of alkaloid scaffolds

    OpenAIRE

    Kieron M. G. O’Connell; Monica Díaz-Gavilán; Galloway, Warren R. J. D.; Spring, David R.

    2012-01-01

    Two-directional synthesis represents an ideal strategy for the rapid elaboration of simple starting materials and their subsequent transformation into complex molecular architectures. As such, it is becoming recognised as an enabling technology for diversity-oriented synthesis. Herein, we provide a thorough account of our work combining two-directional synthesis with diversity-oriented synthesis, with particular reference to the synthesis of polycyclic alkaloid scaffolds.

  10. Synthesis of Acetylhomoagmatine

    Directory of Open Access Journals (Sweden)

    Carmenza Duque

    2006-08-01

    Full Text Available Abstract: The first total synthesis of acetylhomoagmatine, a natural product isolated form the methanolic extracts from the sponge Cliona celata, is performed in four steps in a very high yield.

  11. 2002 Annual report: synthesis

    International Nuclear Information System (INIS)

    This synthesis of the Annual Report 2002 presents information of the main activities on the scope of the radiation protection and nuclear safety of the Nuclear Regulatory Authority (ARN) of the Argentina during 2002

  12. 2000 Annual report: synthesis

    International Nuclear Information System (INIS)

    This synthesis of the Annual Report 2000 present information of the main activities on the scope of the radiation protection and nuclear safety of the Nuclear Regulatory Authority (NRA) of the Argentina during 2000

  13. 2001 Annual report: synthesis

    International Nuclear Information System (INIS)

    This synthesis of the Annual Report 2001 presents information of the main activities on the scope of the radiation protection and nuclear safety of the Nuclear Regulatory Authority (ARN) of the Argentina during 2001

  14. Total synthesis of atropurpuran.

    Science.gov (United States)

    Gong, Jing; Chen, Huan; Liu, Xiao-Yu; Wang, Zhi-Xiu; Nie, Wei; Qin, Yong

    2016-01-01

    Due to their architectural intricacy and biological significance, the synthesis of polycyclic diterpenes and their biogenetically related alkaloids have been the subject of considerable interest over the last few decades, with progress including the impressive synthesis of several elusive targets. Despite tremendous efforts, conquering the unique structural types of this large natural product family remains a long-term challenge. The arcutane diterpenes and related alkaloids, bearing a congested tetracyclo[5.3.3.0(4,9).0(4,12)]tridecane unit, are included in these unsolved enigmas. Here we report a concise approach to the construction of the core structure of these molecules and the first total synthesis of (±)-atropurpuran. Pivotal features of the synthesis include an oxidative dearomatization/intramolecular Diels-Alder cycloaddition cascade, sequential aldol and ketyl-olefin cyclizations to assemble the highly caged framework, and a chemoselective and stereoselective reduction to install the requisite allylic hydroxyl group in the target molecule. PMID:27387707

  15. Catalytic Synthesis Lactobionic Acid

    Directory of Open Access Journals (Sweden)

    V.G. Borodina

    2014-07-01

    Full Text Available Gold nanoparticles are obtained, characterized and deposited on the carrier. Conducted catalytic synthesis of lactobionic acid from lactose. Received lactobionic acid identify on the IR spectrum.

  16. Ethics of Chemical Synthesis

    OpenAIRE

    Joachim Schummer

    2001-01-01

    Unlike other branches of science, the scientific products of synthetic chemistry are not only ideas but also new substances that change our material world, for the benefit or harm of living beings. This paper provides for the first time a systematical analysis of moral issues arising from chemical synthesis, based on concepts of responsibility and general morality. Topics include the questioning of moral neutrality of chemical synthesis as an end in itself, chemical weapons research, moral ob...

  17. Altered ganglioside biosynthesis in mouse cell cultures following transformation with chemical carcinogens and x-irradiation

    International Nuclear Information System (INIS)

    Chemically and x-ray-transformed subclones of BALB/c 3T3 mouse embryo cells were found to have reduced amounts of the mono- and disialogangliosides galactosyl-N-acetylgalactosaminyl-[N-acetylneuraminyl]-galactosylglucosylceramide (G/sub M1/) and N-acetylneuraminylgalactosyl-N-acetylgalactosaminyl-[N-acetylneuraminyl]-galactosylglucosylceramide (G/sub D1a/), and increased amounts of N-acetylgalactosaminyl-[N-acetylneuraminyl]-galactosylglucosylceramide (G/sub M2/). The activity of the enzyme UDP-Gal:G/sub M2/ galactosyltransferase was reduced to between 2.7 and 14.3 percent of normal in the transformed clones. Other ganglioside glycosyltransferase activities were unaffected. This enzymatic change was consistent with the observed alteration in ganglioside pattern in the transformed cells. The residual galactosyltransferase activity in the transformed cells was kinetically similar to the normal enzyme, suggesting that transformation alters ganglioside biosynthesis by blocking enzyme synthesis at the translational or transcriptional levels

  18. Synthesis, characterization and applications of magnetite nanoparticles

    Science.gov (United States)

    Kanmukhla, Vikram Kumar

    In the past few years, the synthesis of magnetic nanoparticles has received considerable attention due to their potential use in clinical applications. Since the properties of these nanoparticles depend strongly on their size, shape and crystallinity, there is a need for a general method to produce these particles with a controlled size, shape and crystal type. Of the many magnetic materials (Co, Ni, and Fe), the magnetite (Fe3O 4) is least toxic and hence most promising for applications in medical diagnostics. Microemulsion-based synthesis utilizes the local aqueous environment within a reverse micelle as a nano-scale reactor and allows synthesizing nanoparticles with a hydrophilic surface for subsequent functionalization. By controlling the water-to-surfactant ratio, the type of surfactants, and the ionic strength of the aqueous core, one can control the size and shape of the resulting particles. We developed such a system that allows the multi-step synthesis of surface-functionalized, magnetic nanoparticles in a one-pot synthesis reaction. By altering the system chemistry, we were further able to produce either spheres or cylinders of controlled dimension in the size range of 5 nm to 30 nm. Using standard bio-conjugation techniques, we successfully immobilized an enzyme onto the nanoparticles. We also developed a theoretical model for the separation and fractionation of nanoparticles based on their size and magnetic properties. Using the multiphysics and finite element modeling capabilities of FEMLAB(TM), we solved the coupled system of PDEs describing the interaction of magnetic particles within a magnetic field for either static (cylindrical beaker) or convective flow (capillary) conditions. A net retention time as high as 310 s is achieved for 200 nm particles at field strength of 1250 kA/m. The model allows the design of a magnetic, field-flow fractionation (MFFF) system to separate nanoparticles by size.

  19. Cerebrospinal fluid space alterations in melancholic depression.

    Directory of Open Access Journals (Sweden)

    Esther Via

    Full Text Available Melancholic depression is a biologically homogeneous clinical entity in which structural brain alterations have been described. Interestingly, reports of structural alterations in melancholia include volume increases in Cerebro-Spinal Fluid (CSF spaces. However, there are no previous reports of CSF volume alterations using automated whole-brain voxel-wise approaches, as tissue classification algorithms have been traditionally regarded as less reliable for CSF segmentation. Here we aimed to assess CSF volumetric alterations in melancholic depression and their clinical correlates by means of a novel segmentation algorithm ('new segment', as implemented in the software Statistical Parametric Mapping-SPM8, incorporating specific features that may improve CSF segmentation. A three-dimensional Magnetic Resonance Image (MRI was obtained from seventy patients with melancholic depression and forty healthy control subjects. Although imaging data were pre-processed with the 'new segment' algorithm, in order to obtain a comparison with previous segmentation approaches, tissue segmentation was also performed with the 'unified segmentation' approach. Melancholic patients showed a CSF volume increase in the region of the left Sylvian fissure, and a CSF volume decrease in the subarachnoid spaces surrounding medial and lateral parietal cortices. Furthermore, CSF increases in the left Sylvian fissure were negatively correlated with the reduction percentage of depressive symptoms at discharge. None of these results were replicated with the 'unified segmentation' approach. By contrast, between-group differences in the left Sylvian fissure were replicated with a non-automated quantification of the CSF content of this region. Left Sylvian fissure alterations reported here are in agreement with previous findings from non-automated CSF assessments, and also with other reports of gray and white matter insular alterations in depressive samples using automated approaches

  20. Traumatic brain injury alters methionine metabolism: implications for pathophysiology

    Directory of Open Access Journals (Sweden)

    Pramod K Dash

    2016-04-01

    Full Text Available Methionine is an essential proteinogenic amino acid that is obtained from the diet. In addition to its requirement for protein biosynthesis, methionine is metabolized to generate metabolites that play key roles in a number of cellular functions. Metabolism of methionine via the transmethylation pathway generates S-adenosylmethionine (SAM that serves as the principal methyl (-CH3 donor for DNA and histone methyltransferases to regulate epigenetic changes in gene expression. SAM is also required for methylation of other cellular proteins that serve various functions and phosphatidylcholine synthesis that participate in cellular signaling.. Under conditions of oxidative stress, homocysteine (which is derived from SAM enters the transsulfuration pathway to generate glutathione, an important cytoprotective molecule against oxidative damage. As both experimental and clinical studies have shown that traumatic brain injury (TBI alters DNA and histone methylation and causes oxidative stress, we examined if TBI alters the plasma levels of methionine and its metabolites in human patients. Blood samples were collected from healthy volunteers (n = 20 and patients with mild TBI (GCS > 12; n = 20 or severe TBI (GCS < 8; n = 20 within the first 24 hours of injury. The levels of methionine and its metabolites in the plasma samples were analyzed by either liquid chromatography-mass spectrometry or gas chromatography-mass spectrometry (LC-MS or GC-MS. Severe TBI decreased the levels of methionine, SAM, betaine and 2-methylglycine as compared to healthy volunteers, indicating a decrease in metabolism through the transmethylation cycle. In addition, precursors for the generation of glutathione, cysteine and glycine were also found to be decreased as were intermediate metabolites of the gamma-glutamyl cycle (gamma-glutamyl amino acids and 5-oxoproline. Mild TBI also decreased the levels of methionine, α-ketobutyrate, 2 hydroxybutyrate and glycine, albeit to lesser

  1. Vitamin A Deficiency and Alterations in the Extracellular Matrix

    Directory of Open Access Journals (Sweden)

    Teresa Barber

    2014-11-01

    Full Text Available Vitamin A or retinol which is the natural precursor of several biologically active metabolites can be considered the most multifunctional vitamin in mammals. Its deficiency is currently, along with protein malnutrition, the most serious and common nutritional disorder worldwide. It is necessary for normal embryonic development and postnatal tissue homeostasis, and exerts important effects on cell proliferation, differentiation and apoptosis. These actions are produced mainly by regulating the expression of a variety of proteins through transcriptional and non-transcriptional mechanisms. Extracellular matrix proteins are among those whose synthesis is known to be modulated by vitamin A. Retinoic acid, the main biologically active form of vitamin A, influences the expression of collagens, laminins, entactin, fibronectin, elastin and proteoglycans, which are the major components of the extracellular matrix. Consequently, the structure and macromolecular composition of this extracellular compartment is profoundly altered as a result of vitamin A deficiency. As cell behavior, differentiation and apoptosis, and tissue mechanics are influenced by the extracellular matrix, its modifications potentially compromise organ function and may lead to disease. This review focuses on the effects of lack of vitamin A in the extracellular matrix of several organs and discusses possible molecular mechanisms and pathologic implications.

  2. Angiotensin II receptor alterations during pregnancy in rabbits

    International Nuclear Information System (INIS)

    Despite activation of the renin-angiotensin system during pregnancy, renal and peripheral vascular blood flows increase, and the systemic blood pressure and the pressor response to exogenous angiotensin II (Ang II) fall. Gestational alterations in Ang II receptors could contribute to these changes. Ang II binding parameters were determining utilizing 125I-Ang II in vascular (glomeruli and mesenteric arteries) and nonvascular (adrenal glomerulosa) tissues from 24- to 28-day pregnant rabbits. Comparisons were made utilizing tissues from nonpregnant rabbits. Binding site concentrations (N) and dissociation constants (K/sub d/) were obtained by Scatchard analyses of binding inhibition data. Meclofenamate (M) inhibits prostaglandin synthesis, reduces plasma renin activity, and enhances the pressor response to infused Ang II in pregnant rabbits. Administration of M to pregnant rabbits increased N in glomerular and in mesenteric artery membranes. These data demonstrate that Ang II receptors in glomeruli and mesenteric arteries are down regulated during gestation in rabbits. Elevated endogenous Ang II during pregnancy in rabbits may contribute to the down regulation of vascular Ang II receptors

  3. Monitoring protein synthesis in single live cancer cells.

    Science.gov (United States)

    Tu, Chengyi; Santo, Loredana; Mishima, Yuko; Raje, Noopur; Smilansky, Zeev; Zoldan, Janet

    2016-05-16

    Protein synthesis is generally under sophisticated and dynamic regulation to meet the ever-changing demands of a cell. Global up or down-regulation of protein synthesis and the shift of protein synthesis location (as shown, for example, during cellular stress or viral infection) are recognized as cellular responses to environmental changes such as nutrient/oxygen deprivation or to alterations such as pathological mutations in cancer cells. Monitoring protein synthesis in single live cells can be a powerful tool for cancer research. Here we employed a microfluidic platform to perform high throughput delivery of fluorescent labeled tRNAs into multiple myeloma cells with high transfection efficiency (∼45%) and high viability (>80%). We show that the delivered tRNAs were actively recruited to the ER for protein synthesis and that treatment with puromycin effectively disrupted this process. Interestingly, we observed the scattered distribution of tRNAs in cells undergoing mitosis, which has not been previously reported. Fluorescence lifetime analysis detected extensive FRET signals generated from tRNAs labeled as FRET pairs, further confirming that the delivered tRNAs were used by active ribosomes for protein translation. Our work demonstrates that the microfluidic delivery of FRET labeled tRNAs into living cancer cells can provide new insights into basic cancer metabolism and has the potential to serve as a platform for drug screening, diagnostics, or personalized medication. PMID:26956582

  4. Expression of small heat shock proteins in Pisum sativum L. under gravity altered conditions

    Directory of Open Access Journals (Sweden)

    Talalaiev A. S.

    2013-11-01

    Full Text Available Altered gravity induces significant changes in the gene expression profiles of the plant cell, which are indicative of stress conditions. One of the molecular mechanisms of cell adaptation is synthesis of small heat shock proteins (sHsp. The sHsps are chaperones, and as such, they assist in the protein folding and prevent the irreversible protein aggregation. Aim. The objective of this research was to determine the effect of simulated microgravity (clinorotation and hypergravity (centrifugation on the sHsp genes expression in the etiolated pea seedlings. Methods. The gene expression was examined with the reverse transcription and real-time PCR. Results. The qPCR results demonstrated that the altered gravity conditions do not change the expression of sHsp genes which belong to the subfamilies of different subcellular localization – cytosolic-nuclear Pshsp 17.1-CII and Pshsp18.1-CI, plastid – Pshsp26.2-P, endoplasmic reticulum – Pshsp22.7-ER and mitochondrial – Pshsp22.9-M. Conclusions. The relative qPCR results demonstrate that altered gravity and temperature elevation have different effects on the sHsp genes: unlike high temperature, altered gravity does not lead to the denaturation of cell proteins and, therefore, does not modulate the sHsp genes expression.

  5. Alter(n – ein vielschichtiger Begriff

    Directory of Open Access Journals (Sweden)

    Nicole Maly-Lukas

    2005-07-01

    Full Text Available Diese Veröffentlichung, die aus einer Vortragsreihe an der katholischen Fachhochschule Freiburg entstanden ist, führt die Leserinnen und Leser in die verschiedenen Sichtweisen des Alter(ns in der modernen Gesellschaft ein. Es handelt sich um eine gelungene Zusammenstellung von Beiträgen aus unterschiedlichen Disziplinen, die sich alle aus ihrer Sicht dem Thema Alter(n widmen. Die einzelnen Artikel sind zwischen 8 und 38 Seiten lang und recht schnell und einfach zu lesen. Je nach Hintergrund und Interessen werden die einzelnen Leserinnen und Leser dabei sicher unterschiedliche Beiträge favorisieren. Schade ist nur, dass durch die ungleichen Längen der Beiträge bestimmte thematische Schwerpunkte – ob gewollt oder nicht – gesetzt werden. Dies sollte die Leserinnen und Leser, die offen für unterschiedlichste Sichtweisen des Alter(ns sind, jedoch nicht davon abhalten, dieses Buch zu lesen.

  6. Public health implications of altered puberty timing

    DEFF Research Database (Denmark)

    Golub, Mari S; Collman, Gwen W; Foster, Paul M D;

    2008-01-01

    sexual debut, potential sexual abuse, and psychosocial difficulties. Altered puberty timing is also of concern for the development of reproductive tract cancers later in life. For example, an early age of menarche is a risk factor for breast cancer. A low age at male puberty is associated....... Altered timing of puberty also has implications for behavioral disorders. For example, an early maturation is associated with a greater incidence of conduct and behavior disorders during adolescence. Finally, altered puberty timing is considered an adverse effect in reproductive toxicity risk assessment...... for chemicals. Recent US legislation has mandated improved chemical testing approaches for protecting children's health and screening for endocrine-disrupting agents, which has led to changes in the US Environmental Protection Agency's risk assessment and toxicity testing guidelines to include puberty...

  7. Chronic citalopram administration causes a sustained suppression of serotonin synthesis in the mouse forebrain.

    Directory of Open Access Journals (Sweden)

    Gerard Honig

    Full Text Available BACKGROUND: Serotonin (5-HT is a neurotransmitter with important roles in the regulation of neurobehavioral processes, particularly those regulating affect in humans. Drugs that potentiate serotonergic neurotransmission by selectively inhibiting the reuptake of serotonin (SSRIs are widely used for the treatment of psychiatric disorders. Although the regulation of serotonin synthesis may be an factor in SSRI efficacy, the effect of chronic SSRI administration on 5-HT synthesis is not well understood. Here, we describe effects of chronic administration of the SSRI citalopram (CIT on 5-HT synthesis and content in the mouse forebrain. METHODOLOGY/PRINCIPAL FINDINGS: Citalopram was administered continuously to adult male C57BL/6J mice via osmotic minipump for 2 days, 14 days or 28 days. Plasma citalopram levels were found to be within the clinical range. 5-HT synthesis was assessed using the decarboxylase inhibition method. Citalopram administration caused a suppression of 5-HT synthesis at all time points. CIT treatment also caused a reduction in forebrain 5-HIAA content. Following chronic CIT treatment, forebrain 5-HT stores were more sensitive to the depleting effects of acute decarboxylase inhibition. CONCLUSIONS/SIGNIFICANCE: Taken together, these results demonstrate that chronic citalopram administration causes a sustained suppression of serotonin synthesis in the mouse forebrain. Furthermore, our results indicate that chronic 5-HT reuptake inhibition renders 5-HT brain stores more sensitive to alterations in serotonin synthesis. These results suggest that the regulation of 5-HT synthesis warrants consideration in efforts to develop novel antidepressant strategies.

  8. Bone alterations by stress in athletes

    International Nuclear Information System (INIS)

    This report describes our experiences with the bone imaging in athletes. We studied 10 athletes and 10 other patients with spondylolisthesis of the lumbar spine and 16 athletes with suspicion of alterations of extremities. An increased uptake of this radiopharmaceutical was detected in six of 10 athletes with spondylolisthesis caused probably by stress fracture. Bone scans were negative in seven of 16 athletes with suspicion of lesion of extremities. In the remaining 9 patients scans were abnormal and showed periosteal injuries, epiphyseal alteration, joint abnormalities, tibial stress fractures and couvert fracture. It was also abnormal in bone injuries not evident in radiography. (orig.)

  9. Public health implications of altered puberty timing

    DEFF Research Database (Denmark)

    Golub, M.S.; Collman, G.W.; Foster, P.M.;

    2008-01-01

    . Altered timing of puberty also has implications for behavioral disorders. For example, an early maturation is associated with a greater incidence of conduct and behavior disorders during adolescence. Finally, altered puberty timing is considered an adverse effect in reproductive toxicity risk assessment...... for chemicals. Recent US legislation has mandated improved chemical testing approaches for protecting children's health and screening for endocrine-disrupting agents, which has led to changes in the US Environmental Protection Agency's risk assessment and toxicity testing guidelines to include puberty......-related assessments and to the validation of pubertal male and female rat assays for endocrine screening Udgivelsesdato: 2008/2...

  10. Questions Regarding Alterity in Social Collaborative Networks

    Directory of Open Access Journals (Sweden)

    Florinela Floria

    2010-01-01

    Full Text Available The idea of alterity has become important in the last decades, when talking about the Information Age, which provides acknowledgement to the software development specialists about the importance of understanding the other’s behavior, needs, objectives and beliefs.
    Our main purpose is to bring to attention the question of social representation related to the images of individuals as different entities that are integrated in virtual teams, virtual projects and e-activities. Regarding the consciousness about the other’s alterity, we assert that it opens a dialogical perspective about the Information Society, where it is essential to share and communicate knowledge to the others.

  11. Portrét-Alter ego

    OpenAIRE

    BUČKOVÁ, Michaela

    2013-01-01

    The bachelor work is focused in the topic of alter ego in art, mainly in portrait and self- portrait. This work is diveded in two parts-theory and practical part. In the first part I´m interested in ?alter ego?- where it comes form, history (shamanism), these days ( body modification). In the sekond part I´m interested in person (as a whole unit), psychology and psychoanalysis. In the end of the theory I remember (notice) an author, who works with simile topics. In the practical part I descri...

  12. Gait Retraining: Altering the Fingerprint of Gait.

    Science.gov (United States)

    Davis, Irene S; Futrell, Erin

    2016-02-01

    In terms of running, there is evidence that links mechanics with injury. This evidence provides the justification for altering these mechanics. Increased hip adduction and vertical impact loading have been most commonly associated with injury. More work is needed in order to understand the optimal way to retrain gait patterns in runners. The human body has a considerable ability to adapt. To provide individuals with the ability to alter faulty movement patterns in ways that can reduce injury risk is a powerful tool. PMID:26616188

  13. Experimental Analysis of Impact Glass Alteration

    Science.gov (United States)

    Kalleson, E.; Dypvik, H.; Hellevang, H.

    2011-12-01

    Phyllosilicates have been suggested to commonly appear on the surface of Mars, mainly associated with Noachian successions. The formation of these aqueous minerals, indicate the presence of liquid water on an early Noachian Mars. In the present project we seek to better understand the alteration process of melt rocks, impact melt in particular. On the Earth large amounts of phyllosilicates have been detected in relation with impact craters and impact glass / melt. In the studies we use impact melt and glasses from different impact structures as starting materials for alteration experiments and modeling of mineral alteration / transformation products. The studied samples vary in age and lithology (glass, suevite and melt), with mineralogical composition partly reflecting the target lithologies at sites of impact. During impact some of the target rocks are melted by the intense heat. Some melt are ejected out of the crater, whereas about half of the melt remains within the impact structure. If water is present, hydrothermal systems may be established within the crater and exist for thousands of years after impact. In the experimental study we aim at representing possible alteration conditions of melt bearing rocks the first few thousand years after an impact. The samples are put into a saline solution containing 30 mg/l NaCl in Parr stirred titanium batch reactors at a temperature of 200 to 230 °C and 15 bar pressure for 3 weeks. The geochemistry / mineralogy of samples and reaction products are studied before and after the alteration experiments (dissolution and precipitation). The experimental results are compared to results of geochemical modeling (PHREEQC) in order to increase our understanding of the chemical reactions during alteration. The alterations products reflect the composition of both the source material and the percolation water. The first results (artificial melt and Chesapeake Bay impact melt) show the formation of smectite, chlinochlore, Fe

  14. Pathological alteration in the choroid plexus of Alzheimer´s disease: implication for new therapy approaches

    Directory of Open Access Journals (Sweden)

    Agnieszka eKrzyzanowska

    2012-05-01

    Full Text Available Morphological alterations of choroid plexus in Alzheimer´s disease (AD have been extensively investigated. These changes include epithelial atrophy, thickening of the basement membrane and stroma fibrosis. As a result, synthesis, secretory, and transportation functions are significantly altered resulting in decreased cerebrospinal fluid (CSF turnover. Recent studies discuss the potential impacts of these changes, including the possibility of reduced resistance to stress insults and slow clearance of toxic compounds from CSF with specific reference to the amyloid peptide. Here, we review new evidences for AD-related changes in the choroid plexus. The data suggest that the significantly altered functions of the choroid plexus contribute to the multiparametric pathogenesis of late-onset AD.

  15. Increased plasma membrane cholesterol in cystic fibrosis cells correlates with CFTR genotype and depends on de novo cholesterol synthesis

    OpenAIRE

    Sonawane Nitin D; Previs Stephen F; Jiang Dechen; Ruddy Jennifer; Manson Mary E; West Richard H; Fang Danjun; Burgess James D; Kelley Thomas J

    2010-01-01

    Abstract Background Previous observations demonstrate that Cftr-null cells and tissues exhibit alterations in cholesterol processing including perinuclear cholesterol accumulation, increased de novo synthesis, and an increase in plasma membrane cholesterol accessibility compared to wild type controls. The hypothesis of this study is that membrane cholesterol accessibility correlates with CFTR genotype and is in part influenced by de novo cholesterol synthesis. Methods Electrochemical detectio...

  16. Connective tissue alteration in abdominal wall hernia

    DEFF Research Database (Denmark)

    Henriksen, N A; Yadete, D H; Sørensen, Lars Tue; Ågren, Sven Per Magnus; Jørgensen, Lars Nannestad

    2011-01-01

    The aetiology and pathogenesis of abdominal wall hernia formation is complex. Optimal treatment of hernias depends on a full understanding of the pathophysiological mechanisms involved in their formation. The aim of this study was to review the literature on specific collagen alterations in abdom...

  17. Acting: An Altered State of Consciousness.

    Science.gov (United States)

    Scheiffele, Eberhard

    2001-01-01

    Uses notions from the field Psychology of Consciousness, including an explanation of how psychologists define and investigate Altered States of Consciousness (ASCs). Argues that actors routinely enter an ASC. Establishes acting as a way to enter an ASC and discusses why theater artists, educators, and advocates need to be aware of both the dangers…

  18. Reorientation from Altered States: Please, More Carefully.

    Science.gov (United States)

    Heikkinen, Charles A.

    1989-01-01

    Claims counselors too often appear to forget to reorient clients from altered states of consciousness used in counseling and that failure to reorient can result in unnecessary discomfort for clients. Provides suggestions for when and how to reorient to avoid unwanted, lingering aftereffects. (Author/ABL)

  19. Direct alteration of a traumatic nightmare.

    Science.gov (United States)

    Halliday, G

    1982-04-01

    A brief case history of a young male farm worker who suffered recurrent nightmares subsequent to being run over by a tractor is given. A method for reducing the nightmares, by encouraging the patient to alter a small, emotionally nonsignificant detail of the dream, is then described. PMID:7079069

  20. Psychobiology of Altered States of Consciousness

    Science.gov (United States)

    Vaitl, Dieter; Birbaumer, Niels; Gruzelier, John; Jamieson, Graham A.; Kotchoubey, Boris; Kubler, Andrea; Lehmann, Dietrich; Miltner, Wolfgang H. R.; Ott, Ulrich; Sammer, Gebhard; Strauch, Inge; Strehl, Ute; Wackermann, Jiri; Weiss, Thomas

    2005-01-01

    The article reviews the current knowledge regarding altered states of consciousness (ASC) (a) occurring spontaneously, (b) evoked by physical and physiological stimulation, (c) induced by psychological means, and (d) caused by diseases. The emphasis is laid on psychological and neurobiological approaches. The phenomenological analysis of the…

  1. SEDAH. Data Server for hydrologic alteration evaluation

    International Nuclear Information System (INIS)

    Several tasks and studies have been developed from 2008 till 2010 all around the country in order to evaluate the hydrologic alteration of water bodies. In most cases this alteraction has been evaluated through IAHRIS (Martinez and Fernandez, 2006). The necessity of creating a new toll that allowed a better performance of the National Flow-Stage Stations Network data was showed up by developing these works. The output data series should match IAHRIS and IHA. SEDAH (Data Server for Evaluating Hydrologic Alteration) Helps to solve some of these problems by supplying an easy way to select flow stations, dates, flow series typology, etc. Moreover, other useful utilities are: a preliminary appraisement of quality data, calssification of altered or reference flow series and exportation of data in different file formats. The web application works with different data bases, daily, monthly and annual series belonging to, wither actual series from flow station data or completed series by statistical procedures. Through SEDAH the user has easy access to all this huge information ready for being applied in hydrologic alteration assessment, environmental fows regime, river restoration projects, etc. Furthermore, this first phase of the application constitute the basis for future powerful functionalities related to the natural flow series obtaining. (Author) 5 refs.

  2. Hemostasis alterations in metabolic syndrome (review).

    Science.gov (United States)

    Palomo, Iván; Alarcón, Marcelo; Moore-Carrasco, Rodrigo; Argilés, Josep M

    2006-11-01

    Metabolic syndrome (MS) is characterized by the presence of at least three of the following alterations: enlargement of the waist diameter, higher levels of arterial pressure, low density lipoprotein cholesterol and glycemia, and reduction of high density lipoprotein cholesterol. The prevalence of MS reaches 23% in young adults, a percentage that increases with age. People with MS have a greater risk of suffering from cardiovascular disease (CVD). The physiopathologic alterations now found to exist in MS are diverse; among them is endothelial dysfunction, which triggers atherogenic lesions and hypercoagulability characterized by alterations of the coagulation factors and the regulatory proteins of fibrinolysis such as the plasminogen activator inhibitor (PAI-1). The increase in oxidative stress and/or the reactive oxygen species in patients with MS is partially related to the oxidation state of the lipoproteins, especially of the low density lipoproteins. This fact favors atherogenesis. Moreover, the oxidative stress produces alterations in the production of adipokines, cytokines secreted by the adipose tissues. The abnormality in the transport of lipoprotein diminishes the catabolism of the very low density lipoprotein (VLDL) and increases the catabolism of the high density lipoprotein (HDL), which creates insulin resistance. This process is associated with a lower concentration of adiponectin that in turn regulates the catabolism of VLDL and HDL; consequently increasing the flow of fatty acids from the adipose tissue to the liver and muscles. The proinflammatory cytokines, among them tumor necrosis factor alpha (TNF-alpha), are of great importance in MS regulating different processes and molecules such as PAI-1. PAI-1 is controlled by the group of transcription factors peroxisome proliferator-activated receptor (PPAR), especially by PPAR gamma and alpha ligands. In summary, MS includes multiple alterations related to insulin resistance at several levels: hepatic

  3. Direct Dimethyl Ether Synthesis

    Institute of Scientific and Technical Information of China (English)

    Takashi Ogawa; Norio Inoue; Tutomu Shikada; Yotaro Ohno

    2003-01-01

    Dimethyl ether (DME) is a clean and economical alternative fuel which can be produced from natural gas through synthesis gas. The properties of DME are very similar to those of LP gas. DME can be used for various fields as a fuel such as power generation, transportation, home heating and cooking,etc. It contains no sulfur or nitrogen. It is not corrosive to any metal and not harmful to human body. An innovative process of direct synthesis of DME from synthesis gas has been developed. Newly developed catalyst in a slurry phase reactor gave a high conversion and high selectivity of DME production. One and half year pilot scale plant (5 tons per day) testing, which was supported by METI, had successfully finished with about 400 tons DME production.

  4. Synthesis of organosilicon compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, G.

    1996-12-31

    Silicon-containing polymers have been a focus of synthesis and study in Dr. Barton`s group because of their chemistry and properties which are not offered by other systems or materials. For example, the polymer -[-SiMe{sub 2}C{triple_bond}C-]{sub n}-can be easily processed to films or fibers from melt or solution, and thermally converted to a SiC-containing ceramic in high yield at high temperature. In recent years, carbosilane dendritic polymers have been of great interests in many research groups. However, no synthesis of carbosilane dendrimers with functionalties both inside and outside the dendrimer has been reported. Functionality is very important in the synthesis of preceramic polymers. This thesis will be devoted to exploring several new organosilicon polymer systems.

  5. Epigenetic alteration of sedimentary rocks at hydrogenic uranium deposit

    International Nuclear Information System (INIS)

    The author introduces the concept, the recognition criteria, the genesis and classification of the epigenetic alteration of sedimentary rocks in brief, and expounds the mineral-geochemical indications and characteristics of oxidation and reduction alterations in different geochemical zones in detail, and proposes the two models of ore-controlling zonation of epigenetic alteration. The authors finally introduce research methods of epigenetic alteration

  6. 28 CFR 36.403 - Alterations: Path of travel.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alterations: Path of travel. 36.403... Alterations: Path of travel. (a) General. An alteration that affects or could affect the usability of or... the maximum extent feasible, the path of travel to the altered area and the restrooms, telephones,...

  7. Stereoselective Synthesis of (+)-Boronolide

    Institute of Scientific and Technical Information of China (English)

    HU,Shou-Gang; HU,Tai-Shan; WU,Yu-Lin

    2004-01-01

    @@ (+)-Boronolide (1) and its deacetylated products have attracted much attention of synthetic chemists due to their diverse biological properties as well as their structural complexities.[1] Many of these reported synthesis involved dehydrogenation of δ-lactone by using benzeneseleninic anhydride or ring-closing olefin metathesis (RCM) to introduce the requisite α,β-unsaturated δ-lactone in boronolide. Here, we report the synthesis of boronolide with diastereoselective propargylation of α-hydroxy aldehyde as the key step and D-gluconolactone as the starting material.

  8. Supercritical Synthesis of Biodiesel

    Directory of Open Access Journals (Sweden)

    Michel Vaultier

    2012-07-01

    Full Text Available The synthesis of biodiesel fuel from lipids (vegetable oils and animal fats has gained in importance as a possible source of renewable non-fossil energy in an attempt to reduce our dependence on petroleum-based fuels. The catalytic processes commonly used for the production of biodiesel fuel present a series of limitations and drawbacks, among them the high energy consumption required for complex purification operations and undesirable side reactions. Supercritical fluid (SCF technologies offer an interesting alternative to conventional processes for preparing biodiesel. This review highlights the advances, advantages, drawbacks and new tendencies involved in the use of supercritical fluids (SCFs for biodiesel synthesis.

  9. Diophantine frequency synthesis.

    Science.gov (United States)

    Sotiriadis, Paul Peter

    2006-11-01

    A methodology for fine-step, fast-hopping, low-spurs phase-locked loop based frequency synthesis is presented. It uses mathematical properties of integer numbers and linear Diophantine equations to overcome the constraining relation between frequency step and phase-comparator frequency that is inherent in conventional phase-locked loop based frequency synthesis. The methodology leads to fine-step, fast-hopping, modular-structured frequency synthesizers with potentially very low spurs, especially in the vicinity of the carrier. The paper focuses on the mathematical principles of the new methodology and the related number theoretic algorithms. PMID:17091835

  10. Asymmetric Synthesis of Fluoroamines from Chiral Aziridines

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyeonjeong; Yoon, Dooha; Ha, Hyunjoon [Hankuk Univ. of Foreign Studies, Yongin (Korea, Republic of); Son, Se In; Lee, Won Koo [Sogang Univ., Seoul (Korea, Republic of)

    2014-03-15

    We described an efficient preparation of fluoroamines by the ring-opening reactions of chiral aziridines with Et{sub 3}N·3HF. At most cases both regioisomers were obtained from the ring openings at C2 and C3 positions depending on the substituents at C2 of the starting substrates.The fluorinated organic molecules have attracted great attentions from synthetic and medicinal chemists with wide use of various agrochemicals and pharmaceuticals. Their uniqueness is originated from its electronic characteristics and the small size without altering the molecular conformations of non-fluorinated compounds. The fluorine is the second most widely used atom in the commercial drugs following the amine. Thereby, the elaboration of fluoro-amines bearing two most widely used atoms in drugs is one of the most challenging problems in drug synthesis and its development.

  11. Studies on the possible role of thyroid hormone in altered muscle protein turnover during sepsis

    International Nuclear Information System (INIS)

    Five days after thyroidectomy (Tx) or sham-Tx in young male Sprague-Dawley rats, sepsis was induced by cecal ligation and puncture (CLP). Control animals underwent laparotomy and manipulation of the cecum without ligation or puncture. Sixteen hours after CLP or laparotomy, protein synthesis and degradation were measured in incubated extensor digitorum longus (EDL) and soleus (SOL) muscles by determining rate of 14C-phenylalanine incorporation into protein and tyrosine release into incubation medium, respectively. Triiodothyronine (T3) was measured in serum and muscle tissue. Protein synthesis was reduced by 39% and 22% in EDL and SOL, respectively, 16 hours after CLP in sham-Tx rats. The response to sepsis of protein synthesis was abolished in Tx rats. Protein breakdown was increased by 113% and 68% in EDL and SOL, respectively, 16 hours after CLP in sham-Tx animals. The increase in muscle proteolysis during sepsis was blunted in hypothyroid animals and was 42% and 49% in EDL and SOL, respectively. T3 in serum was reduced by sepsis, both in Tx and sham-Tx rats. T3 in muscle, however, was maintained or increased during sepsis. Abolished or blunted response of muscle protein turnover after CLP in hypothyroid animals may reflect a role of thyroid hormones in altered muscle protein metabolism during sepsis. Reduced serum levels of T3, but maintained or increased muscle concentrations of the hormone, suggests that increased T3 uptake by muscle may be one mechanism of low T3 syndrome in sepsis, further supporting the concept of a role for thyroid hormone in metabolic alterations in muscle during sepsis

  12. Postnatal manganese exposure does not alter dopamine autoreceptor sensitivity in adult and adolescent male rats.

    Science.gov (United States)

    McDougall, Sanders A; Mohd-Yusof, Alena; Kaplan, Graham J; Abdulla, Zuhair I; Lee, Ryan J; Crawford, Cynthia A

    2013-04-15

    Administering manganese chloride (Mn) to rats on postnatal day (PD) 1-21 causes long-term reductions in dopamine transporter levels in the dorsal striatum, as well as a persistent increase in D1 and D2 receptor concentrations. Whether dopamine autoreceptors change in number or sensitivity is uncertain, although D2S receptors, which may be presynaptic in origin, are elevated in Mn-exposed rats. The purpose of this study was to determine if early Mn exposure causes long-term changes in dopamine autoreceptor sensitivity that persist into adolescence and adulthood. To this end, male rats were exposed to Mn on PD 1-21 and autoreceptor functioning was tested 7 or 70 days later by measuring (a) dopamine synthesis (i.e., DOPA accumulation) in the dorsal striatum after quinpirole or haloperidol treatment and (b) behavioral responsiveness after low-dose apomorphine treatment. Results showed that low doses (i.e., "autoreceptor" doses) of apomorphine (0.06 and 0.12 mg/kg) decreased the locomotor activity of adolescent and adult rats, while higher doses increased locomotion. The dopamine synthesis experiment also produced classic autoreceptor effects, because quinpirole decreased dorsal striatal DOPA accumulation; whereas, haloperidol increased DOPA levels in control rats, but not in rats given the nerve impulse inhibitor γ-butyrolactone. Importantly, early Mn exposure did not alter autoreceptor sensitivity when assessed in early adolescence or adulthood. The lack of Mn-induced effects was evident in both the dopamine synthesis and behavioral experiments. When considered together with past studies, it is clear that early Mn exposure alters the functioning of various dopaminergic presynaptic mechanisms, while dopamine autoreceptors remain unimpaired. PMID:23458069

  13. Overexpression of Patatin-Related Phospholipase AIIIβ Altered the Content and Composition of Sphingolipids in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Maoyin eLi

    2014-10-01

    Full Text Available In plants, fatty acids are primarily synthesized in plastids and then transported to the endoplasmic reticulum for synthesis of most of the complex membrane lipids, including glycerolipids and sphingolipids. The first step of sphingolipid synthesis, which uses a fatty acid and a serine as substrates, is critical for sphingolipid homeostasis; its disruption leads to an altered plant growth. Phospholipase As (PLAs have been implicated in the trafficking of fatty acids from plastids to the endoplasmic reticulum. Previously, we found that overexpression of a patatin-related phospholipase, pPLAIIIβ, resulted in a smaller plant size and altered anisotropic cell expansion. Here, we determined the content and composition of sphingolipids in pPLAIIIβ-knockout and overexpression plants (pPLAIIIβ-KO and -OE. 3-keto-sphinganine, the product of the first step of sphingolipid synthesis, had a 26% decrease in leaves of pPLAIIIβ-KO while a 52% increase in pPLAIIIβ-OE compared to wild type (WT. The levels of free long-chain base species, dihydroxy-C18:0 and trihydroxy-18:0 (d18:0 and t18:0, were 38% and 97% higher, respectively, in pPLAIIIβ-OE than in WT. The level of complex sphingolipids ceramide d18:0-16:0 and t18:1-16:0 had a 2-fold increase in pPLAIIIβ-OE. The level of hydroxyceramide d18:0-h16:0 was 72% higher in pPLAIIIβ-OE compared to WT. The levels of several species of glucosylceramide and glycosylinositolphosphoceramide tended to be higher in pPLAIIIβ-OE than in WT. The total content of the complex sphingolipids showed a slightly higher in pPLAIIIβ-OE than in WT. These results revealed an involvement of phospholipase-mediated lipid homeostasis in plant growth.

  14. Impact of selenium supplementation on fish antiviral responses: a whole transcriptomic analysis in rainbow trout (Oncorhynchus mykiss) fed supranutritional levels of Sel-Plex®

    OpenAIRE

    Pacitti, D.; Lawan, M. M.; Feldmann, J.; Sweetman, J.; T. Wang; Martin, S A M; Secombes, C.J.

    2016-01-01

    Background Selenium (Se) is required for the synthesis of proteins (selenoproteins) with essential biological functions. Selenoproteins have a crucial role in the maintenance of cellular redox homeostasis in nearly all tissues, and are also involved in thyroid hormone metabolism, inflammation and immunity. Several immune processes rely on Se status and can be compromised if this element is present below the required level. Previous work has supported the notion that when Se is delivered at le...

  15. Microbial colonization and alteration of basaltic glass

    Directory of Open Access Journals (Sweden)

    J. Einen

    2006-03-01

    Full Text Available Microorganisms have been reported to be associated with the alteration of the glassy margin of seafloor pillow basalts (Thorseth et al., 2001, 2003; Lysnes et al., 2004. The amount of iron and other biological important elements present in basalts and the vast abundance of basaltic glass in the earth's crust, make glass alteration an important process in global element cycling. To gain further insight into microbial communities associated with glass alteration, five microcosm experiments mimicking seafloor conditions were inoculated with seafloor basalt and incubated for one year. Mineral precipitations, microbial attachment to the glass and glass alteration were visualized by scanning electron microscopy (SEM, and the bacterial community composition was fingerprinted by PCR and denaturing gradient gel electrophoresis (DGGE in combination with sequencing. SEM analysis revealed a microbial community with low morphological diversity of mainly biofilm associated and prosthecate microorganisms. Approximately 30 nm thick alteration rims developed on the glass in all microcosms after one year of incubation; this however was also seen in non inoculated controls. Calcium carbonate precipitates showed parallel, columnar and filamentous crystallization habits in the microcosms as well as in the sterile controls. DGGE analysis showed an alteration in bacterial community profiles in the five different microcosms, as a response to the different energy and redox regimes and time. In all microcosms a reduction in number of DGGE bands, in combination with an increase in cell abundance were recorded during the experiment. Sequence analysis showed that the microcosms were dominated by four groups of organisms with phylogenetic affiliation to four taxa: The Rhodospirillaceae, a family containing phototrophic marine organisms, in which some members are capable of heterotrophic growth in darkness and N2 fixation; the family Hyphomicrobiaceae, a group

  16. Hypergravity-induced altered behavior in Drosophila

    Science.gov (United States)

    Hosamani, Ravikumar; Wan, Judy; Marcu, Oana; Bhattacharya, Sharmila

    2012-07-01

    Microgravity and mechanical stress are important factors of the spaceflight environment, and affect astronaut health and behavior. Structural, functional, and behavioral mechanisms of all cells and organisms are adapted to Earth's gravitational force, 1G, while altered gravity can pose challenges to their adaptability to this new environment. On ground, hypergravity paradigms have been used to predict and complement studies on microgravity. Even small changes that take place at a molecular and genetic level during altered gravity may result in changes in phenotypic behavior. Drosophila provides a robust and simple, yet very reliable model system to understand the complexity of hypergravity-induced altered behavior, due to availability of a plethora of genetic tools. Locomotor behavior is a sensitive parameter that reflects the array of molecular adaptive mechanisms recruited during exposure to altered gravity. Thus, understanding the genetic basis of this behavior in a hypergravity environment could potentially extend our understanding of mechanisms of adaptation in microgravity. In our laboratory we are trying to dissect out the cellular and molecular mechanisms underlying hypergravity-induced oxidative stress, and its potential consequences on behavioral alterations by using Drosophila as a model system. In the present study, we employed pan-neuronal and mushroom body specific knock-down adult flies by using Gal4/UAS system to express inverted repeat transgenes (RNAi) to monitor and quantify the hypergravity-induced behavior in Drosophila. We established that acute hypergravity (3G for 60 min) causes a significant and robust decrease in the locomotor behavior in adult Drosophila, and that this change is dependent on genes related to Parkinson's disease, such as DJ-1α , DJ-1β , and parkin. In addition, we also showed that anatomically the control of this behavior is significantly processed in the mushroom body region of the fly brain. This work links a molecular

  17. Microbial colonization and alteration of basaltic glass

    Science.gov (United States)

    Einen, J.; Kruber, C.; Øvreås, L.; Thorseth, I. H.; Torsvik, T.

    2006-03-01

    Microorganisms have been reported to be associated with the alteration of the glassy margin of seafloor pillow basalts (Thorseth et al., 2001, 2003; Lysnes et al., 2004). The amount of iron and other biological important elements present in basalts and the vast abundance of basaltic glass in the earth's crust, make glass alteration an important process in global element cycling. To gain further insight into microbial communities associated with glass alteration, five microcosm experiments mimicking seafloor conditions were inoculated with seafloor basalt and incubated for one year. Mineral precipitations, microbial attachment to the glass and glass alteration were visualized by scanning electron microscopy (SEM), and the bacterial community composition was fingerprinted by PCR and denaturing gradient gel electrophoresis (DGGE) in combination with sequencing. SEM analysis revealed a microbial community with low morphological diversity of mainly biofilm associated and prosthecate microorganisms. Approximately 30 nm thick alteration rims developed on the glass in all microcosms after one year of incubation; this however was also seen in non inoculated controls. Calcium carbonate precipitates showed parallel, columnar and filamentous crystallization habits in the microcosms as well as in the sterile controls. DGGE analysis showed an alteration in bacterial community profiles in the five different microcosms, as a response to the different energy and redox regimes and time. In all microcosms a reduction in number of DGGE bands, in combination with an increase in cell abundance were recorded during the experiment. Sequence analysis showed that the microcosms were dominated by four groups of organisms with phylogenetic affiliation to four taxa: The Rhodospirillaceae, a family containing phototrophic marine organisms, in which some members are capable of heterotrophic growth in darkness and N2 fixation; the family Hyphomicrobiaceae, a group of prosthecate oligotrophic

  18. An Approach to Interface Synthesis

    DEFF Research Database (Denmark)

    Madsen, Jan; Hald, Bjarne

    1995-01-01

    Presents a novel interface synthesis approach based on a one-sided interface description. Whereas most other approaches consider interface synthesis as optimizing a channel to existing client/server modules, we consider the interface synthesis as part of the client/server module synthesis (which...... may contain the re-use of existing modules). The interface synthesis approach describes the basic transformations needed to transform the server interface description into an interface description on the client side of the communication medium. The synthesis approach is illustrated through a point......-to-point communication, but is applicable to synthesis of a multiple client/server environment. The interface description is based on a formalization of communication events....

  19. Metabolic alterations in bladder cancer: applications for cancer imaging.

    Science.gov (United States)

    Whyard, Terry; Waltzer, Wayne C; Waltzer, Douglas; Romanov, Victor

    2016-02-01

    Treatment planning, outcome and prognosis are strongly related to the adequate tumor staging for bladder cancer (BC). Unfortunately, a large discrepancy exists between the preoperative clinical and final pathologic staging. Therefore, an advanced imaging-based technique is crucial for adequate staging. Although Magnetic Resonance Imaging (MRI) is currently the best in vivo imaging technique for BC staging because of its excellent soft-tissue contrast and absence of ionizing radiation it lacks cancer-specificity. Tumor-specific positron emission tomography (PET), which is based on the Warburg effect (preferential uptake of glucose by cancer cells), exploits the radioactively-labeled glucose analogs, i.e., FDG. Although FDG-PET is highly cancer specific, it lacks resolution and contrast quality comparable with MRI. Chemical Exchange Saturation Transfer (CEST) MRI enables the detection of low concentrations of metabolites containing protons. BC is an attractive target for glucose CEST MRI because, in addition to the typical systemic administration, glucose might also be directly applied into the bladder to reduce toxicity-related complications. As a first stage of the development of a contrast-specific BC imaging technique we have studied glucose uptake by bladder epithelial cells and have observed that glucose is, indeed, consumed by BC cells with higher intensity than by non-transformed urothelial cells. This effect might be partly explained by increased expression of glucose transporters GLUT1 and GLUT3 in transformed cells as compared to normal urothelium. We also detected higher lactate production by BC cells which is another cancer-specific manifestation of the Warburg effect. In addition, we have observed other metabolic alterations in BC cells as compared to non-transformed cells: in particular, increased pyruvate synthesis. When glucose was substituted by glutamine in culture media, preferential uptake of glutamine by BC cells was observed. The preferential

  20. Experimental alteration of basalt glass applied to the alteration of nuclear waste glass

    International Nuclear Information System (INIS)

    The main objective of the experiments was to produce in the laboratory an altered basalt glass similar to basalt glass altered in a natural environment. This objective has been accomplished with a very good correlation between the observed alteration of basalt glass in a natural environment with that in the laboratory. The formation of the amorphous hydration layer, smectite, analcime, calcium carbonate, and thomsonite all have been observed in natural glass samples that have undergone palagonitization. The SRL 165 glass reacts to a greater extent than the synthetic basalt glass under the same conditions. The alteration of SRL 165 glass produced a smectite clay, analcime, and gyrolite similar to that produced by the synthetic basalt glass

  1. Lack of Globulin Synthesis during Seed Development Alters Accumulation of Seed Storage Proteins in Rice

    Directory of Open Access Journals (Sweden)

    Hye-Jung Lee

    2015-06-01

    Full Text Available The major seed storage proteins (SSPs in rice seeds have been classified into three types, glutelins, prolamins, and globulin, and the proportion of each SSP varies. It has been shown in rice mutants that when either glutelins or prolamins are defective, the expression of another type of SSP is promoted to counterbalance the deficit. However, we observed reduced abundances of glutelins and prolamins in dry seeds of a globulin-deficient rice mutant (Glb-RNAi, which was generated with RNA interference (RNAi-induced suppression of globulin expression. The expression of the prolamin and glutelin subfamily genes was reduced in the immature seeds of Glb-RNAi lines compared with those in wild type. A proteomic analysis of Glb-RNAi seeds showed that the reductions in glutelin and prolamin were conserved at the protein level. The decreased pattern in glutelin was also significant in the presence of a reductant, suggesting that the polymerization of the glutelin proteins via intramolecular disulfide bonds could be interrupted in Glb-RNAi seeds. We also observed aberrant and loosely packed structures in the storage organelles of Glb-RNAi seeds, which may be attributable to the reductions in SSPs. In this study, we evaluated the role of rice globulin in seed development, showing that a deficiency in globulin could comprehensively reduce the expression of other SSPs.

  2. Metabolic engineering of the morphology of Aspergillus oryzae by altering chitin synthesis

    DEFF Research Database (Denmark)

    Muller, C.; Mcintyre, Mhairi; Hansen, Kim;

    2002-01-01

    not significantly different in the three strains. A strain in which the transcription of chsB could be controlled by the nitrogen source-regulated promoter niiA (NiiA1) was examined during chemostat cultivation, and it was found that the branching intensity could be regulated by regulating the...

  3. Altered molecular specificity of surfactant phosphatidycholine synthesis in patients with acute respiratory distress syndrome

    OpenAIRE

    Dushianthan, Ahilanandan; Goss, Victoria; Cusack, Rebecca; Grocott, Michael P. W.; Postle, Anthony D

    2014-01-01

    Background Acute respiratory distress syndrome (ARDS) is a life-threatening critical illness, characterised by qualitative and quantitative surfactant compositional changes associated with premature airway collapse, gas-exchange abnormalities and acute hypoxic respiratory failure. The underlying mechanisms for this dysregulation in surfactant metabolisms are not fully explored. Lack of therapeutic benefits from clinical trials, highlight the importance of detailed in-vivo analysis and charact...

  4. Decreased hepatotoxic bile acid composition and altered synthesis in progressive human nonalcoholic fatty liver disease

    Czech Academy of Sciences Publication Activity Database

    Lake, A.D.; Novák, Petr; Shipkova, P.; Aranibar, N.; Robertson, D.; Reily, M.D.; Lu, Z.; Lehman-McKeeman, L.D.; Cherrington, N.J.

    2013-01-01

    Roč. 268, č. 2 (2013), s. 132-140. ISSN 0041-008X Institutional research plan: CEZ:AV0Z50510513 Institutional support: RVO:60077344 Keywords : Bile Acids * Liver * Metabolomics Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.630, year: 2013

  5. Fullerene synthesis by alteration of coal and shale by simulated lightning

    Czech Academy of Sciences Publication Activity Database

    Frank, O.; Jehlička, J.; Hamplová, Věra; Svatoš, A.

    Berlin : Springer Verlag, 2006 - (Rietmeijer, F.J.M.), s. 241-254 ISBN 1-4020-4134-9. - (Developments in Fulleren Science. 6) Grant ostatní: GA MSM FRVS 2307/2002; GAUK(CZ) 212/1999 B GEO Institutional research plan: CEZ:AV0Z10100520 Keywords : arc discharge * coal * shale * shungite * high performance liquid chromtography Subject RIV: BM - Solid Matter Physics ; Magnetism

  6. Distributed Priority Synthesis

    Directory of Open Access Journals (Sweden)

    Harald Ruess

    2012-11-01

    Full Text Available Given a set of interacting components with non-deterministic variable update and given safety requirements, the goal of priority synthesis is to restrict, by means of priorities, the set of possible interactions in such a way as to guarantee the given safety conditions for all possible runs. In distributed priority synthesis we are interested in obtaining local sets of priorities, which are deployed in terms of local component controllers sharing intended next moves between components in local neighborhoods only. These possible communication paths between local controllers are specified by means of a communication architecture. We formally define the problem of distributed priority synthesis in terms of a multi-player safety game between players for (angelically selecting the next transition of the components and an environment for (demonically updating uncontrollable variables. We analyze the complexity of the problem, and propose several optimizations including a solution-space exploration based on a diagnosis method using a nested extension of the usual attractor computation in games together with a reduction to corresponding SAT problems. When diagnosis fails, the method proposes potential candidates to guide the exploration. These optimized algorithms for solving distributed priority synthesis problems have been integrated into the VissBIP framework. An experimental validation of this implementation is performed using a range of case studies including scheduling in multicore processors and modular robotics.

  7. Synthesis of new radiotracers

    International Nuclear Information System (INIS)

    The brain's sensibility besides to the rigorous selectivity of changes taking place on brain's barriers leads us to synthesis specifics radiotracers based on diamine ethylene and marked with technetium radioisotope to form a radiotracer able to pass these barriers and diagnose illnesses in an early stage. These radiotracers are tested by a biodistribution on a small animal to be ratified. (Author)

  8. Synthesis of acrylic prepolymer

    International Nuclear Information System (INIS)

    An acrylic prepolymer was synthesized from glycidyl methacrylate (GMA), butyl methacrylate (BMA), methyl methacrylate (MMA) and acrylic acid (AA). Butyl acetate (BAc), benzoyl peroxide (BzO), 4-methoxyphenol (MPh) and triethylamine (TEA) were used as solvent, initiator, inhibitor and catalyst respectively. Observations of the synthesis leading to the formation of acrylic prepolymer are described. (author)

  9. Synthesis de 1-dotriacotanol

    International Nuclear Information System (INIS)

    In order to prepare isotopic labeled long chain aliphatic primary alcohol's, the synthesis overall yielding and chemical purity of 1-dotriacotanol were 41% and 98%, respectively. This procedure is very useful for carbon-14 and tritium labeling at Beta position of saturated fatty alcohol's

  10. The Synthesis of Glycoglycerolipids

    Institute of Scientific and Technical Information of China (English)

    Chun Xia LI; Ying Xia LI; Ling Bo YU; Hua ZHANG; Shi Dong CHU; Hua Shi GUAN

    2003-01-01

    A convenient synthetic route was developed for the synthesis of the novel glycolipids: 1, 2-di-O-acyl-3-O-(2'-acylamide-2'-deoxy-α-D-glucopyranosyl)-sn-glycerols. 10 new compounds of glycolipids with different acyl groups were obtained.

  11. Enzymatic synthesis of vanillin

    NARCIS (Netherlands)

    van den Heuvel, RHH; Fraaije, MW; Laane, C; van Berkel, WJH; Heuvel, Robert H.H. van den; Berkel, Willem J.H. van

    2001-01-01

    Due to increasing interest in natural vanillin, two enzymatic routes for the synthesis of vanillin were developed. The flavoprotein vanillyl alcohol oxidase (VAO) acts on a wide range of phenolic compounds and converts both creosol and vanillylamine to vanillin with high yield. The VAO-mediated conv

  12. Matrix Synthesis and Characterization

    Science.gov (United States)

    1984-01-01

    The role of NASA in the area of composite material synthesis; evaluation techniques; prediction analysis techniques; solvent-resistant tough composite matrix; resistance to paint strippers; acceptable processing temperature and pressure for thermoplastics; and the role of computer modeling and fiber interface improvement were discussed.

  13. Postural Stability is Altered by Blood Shift

    Science.gov (United States)

    Marais, M.; Denise, P.; Guincetre, J. Y.; Normand, H.

    2008-06-01

    Non-vestibular influences as shift in blood volume changed perception of body posture. Then, factors affecting blood shift may alter postural control. The purpose of our study was to investigate the effects of leg venous contention on postural stability. Twelve subjects were studied on a balance plate for 5 minutes with the eyes closed, in 3 conditions: with no leg venous contention or grade 1 and 3 support stockings. Standard deviation of x and y position was calculated before and after the closure of the eyes. Strong venous contention altered postural stability, after the eyes were closed, during the first 10 s of standing. As support stockings prevent blood shift induced by upright posture, this result is in line with the hypothesis that blood shifts influence the perception of body orientation and postural control among others factors as vision, vestibular inputs... This strong venous contention could induce an increase of fall.

  14. Epigenetic alterations of sedimentary rocks at deposits

    International Nuclear Information System (INIS)

    Notions are explained, and technique for studying epigenetic alterations of sedimentary rocks at uranium deposits is described. Main types of epigenetic transformations and their mineralogic-geochemical characteristics are considered. Rock alterations, accompanying uranium mineralization, can be related to 2 types: oxidation and reduction. The main mineralogic-geochemical property of oxidation transformations is epigenetic limonitization. Stratal limonitization in primary grey-coloured terrigenic rocks and in epigenetically reduced (pyritized) rocks, as well as in rock, subjected to epigenetic gleying, are characterized. Reduction type of epigenetic transformations is subdivided into sulphidic and non-sulphidic (gley) subtypes. Sulphidic transformations in grey-coloured terrigenic rocks with organic substance of carbonic row, in rocks, containing organic substance of oil row, sulphide transformations of sedimentary rocks, as well as gley transformations, are considered

  15. White matter microstructure alterations in bipolar disorder

    Science.gov (United States)

    Bellani, Marcella; Perlini, Cinzia; Ferro, Adele; Cerruti, Stefania; Rambaldelli, Gianluca; Isola, Miriam; Cerini, Roberto; Dusi, Nicola; Andreone, Nicola; Balestrieri, Matteo; Mucelli, Roberto Pozzi; Tansella, Michele; Brambilla, Paolo

    2012-01-01

    Summary Genetic, neuropathological and magnetic resonance imaging findings support the presence of diffuse white matter cytoarchitectural disruption in bipolar disorder. In this study, diffusion-weighted imaging (DWI) was applied to study cortical white matter microstructure organisation in 24 patients with DSM-IV bipolar disorder and 35 matched normal controls. DWI images were obtained using a 1.5 Tesla scanner and apparent diffusion coefficient (ADC) values were determined over regions of interest placed, bilaterally, in the frontal, temporal, parietal, and occipital white matter. Significantly increased ADC values were found in bipolar patients with respect to normal controls in the right temporal lobe, left parietal lobe and bilateral occipital lobes. ADC values did not associate significantly with age or with clinical variables (p>0.05). Diffuse cortical white matter alterations on DWI in bipolar disorder denote widespread disruption of white matter integrity and may be due to altered myelination and/or axonal integrity. PMID:22687164

  16. Alteration of diaspore by thermal treatment

    Institute of Scientific and Technical Information of China (English)

    杨华明; 胡岳华; 杨武国; 敖伟琴; 邱冠周

    2004-01-01

    Diaspore (α-AlOOH) was heated at various temperatures from 300 to 1000 ℃ for 2 h. The alteration of diaspore by thermal treatment was investigated by differential thermal analysis, thermogravimetric analysis and X-ray diffraction. The mechanism of thermal decomposition of diaspore was discussed according to the Coats-Redfern equation. It is found that after thermal treatment at 500 ℃, diaspore is transformed entirely to corundum (α-Al2O3). Combined with the mass loss ratio obtained from the thermogravimetric analysis data, the activation energies for the thermal treatment of diaspore are calculated as Ea=10.4 kJ/mol below 400 ℃ and Eb=47.5 kJ/mol above 400 ℃, respectively, which is directly related to the structural alteration of diaspore during the thermal treatment. The results indicate that the thermal decomposition of diaspore is conducted primarily by means of an interfacial reaction.

  17. Altered Sensory Feedbacks in Pianist's Dystonia: the altered auditory feedback paradigm and the glove effect

    Directory of Open Access Journals (Sweden)

    Felicia Pei-Hsin Cheng

    2013-12-01

    Full Text Available Background: This study investigates the effect of altered auditory feedback (AAF in musician's dystonia (MD and discusses whether altered auditory feedback can be considered as a sensory trick in MD. Furthermore, the effect of AAF is compared with altered tactile feedback, which can serve as a sensory trick in several other forms of focal dystonia. Methods: The method is based on scale analysis (Jabusch et al. 2004. Experiment 1 employs synchronization paradigm: 12 MD patients and 25 healthy pianists had to repeatedly play C-major scales in synchrony with a metronome on a MIDI-piano with 3 auditory feedback conditions: 1. normal feedback; 2. no feedback; 3. constant delayed feedback. Experiment 2 employs synchronization-continuation paradigm: 12 MD patients and 12 healthy pianists had to repeatedly play C-major scales in two phases: first in synchrony with a metronome, secondly continue the established tempo without the metronome. There are 4 experimental conditions, among them 3 are the same altered auditory feedback as in Experiment 1 and 1 is related to altered tactile sensory input. The coefficient of variation of inter-onset intervals of the key depressions was calculated to evaluate fine motor control. Results: In both experiments, the healthy controls and the patients behaved very similarly. There is no difference in the regularity of playing between the two groups under any condition, and neither did AAF nor did altered tactile feedback have a beneficial effect on patients’ fine motor control. Conclusions: The results of the two experiments suggest that in the context of our experimental designs, AAF and altered tactile feedback play a minor role in motor coordination in patients with musicians' dystonia. We propose that altered auditory and tactile feedback do not serve as effective sensory tricks and may not temporarily reduce the symptoms of patients suffering from MD in this experimental context.

  18. Alterations of lipid metabolism in Wilson disease

    OpenAIRE

    Stremmel Wolfgang; Eckert Nicola; Pfeiffenberger Jan; Gotthardt Daniel; Gohdes Annina; Seessle Jessica; Reuner Ulrike; Weiss Karl

    2011-01-01

    Abstract Introduction Wilson disease (WD) is an inherited disorder of human copper metabolism, characterised by accumulation of copper predominantly in the liver and brain, leading to severe hepatic and neurological disease. Interesting findings in animal models of WD (Atp7b-/- and LEC rats) showed altered lipid metabolism with a decrease in the amount of triglycerides and cholesterol in the serum. However, serum lipid profile has not been investigated in large human WD patient cohorts to dat...

  19. Inflammation and Immune System Alterations in Frailty

    OpenAIRE

    Yao, Xu; Li, Huifen; Leng, Sean X.

    2011-01-01

    Frailty is an important geriatric syndrome characterized by multi-system dysregulation. Substantial evidence suggests heightened inflammatory state and significant immune system alterations in frailty. A heightened inflammatory state is marked by increases in levels of inflammatory molecules (IL-6 and CRP) and counts of white blood cell and its subpopulations, which may play an important role in the pathogenesis of frailty, directly or through its detrimental influence to other physiologic sy...

  20. Postoperative Alterations in Taste and Smell

    OpenAIRE

    Elterman, Kelly Galina; Mallampati, Seshagiri Rao; Kaye, Alan David; Urman, Richard Dennis

    2014-01-01

    Context: Alterations in taste and smell, including but not limited to anosmia, ageusia, hypogeusia, and dysgeusia, have been described in association with various medications, including anesthetic agents. Frequently, these symptoms occur 1-2 weeks after medication administration and last several months. While such a phenomenon is a rare occurrence, it nonetheless can significantly impact patients’ satisfaction and quality of life. Evidence Acquisition: The methodology consisted of a thorough ...

  1. Questions Regarding Alterity in Social Collaborative Networks

    OpenAIRE

    Florinela Floria; Cosmin Ion Tomozei

    2010-01-01

    The idea of alterity has become important in the last decades, when talking about the Information Age, which provides acknowledgement to the software development specialists about the importance of understanding the other’s behavior, needs, objectives and beliefs.
    Our main purpose is to bring to attention the question of social representation related to the images of individuals as different entities that are integrated in virtual teams, virtual projects and e-activities....

  2. Altered Levels of Acetylcholinesterase in Alzheimer Plasma

    OpenAIRE

    García Ayllón, María Salud; Riba Llena, Iolanda; Serra Basante, Carol; Alom, Jordi; Boopathy, Rathnam; Sáez-Valero, Javier

    2010-01-01

    Background Many studies have been conducted in an extensive effort to identify alterations in blood cholinesterase levels as a consequence of disease, including the analysis of acetylcholinesterase (AChE) in plasma. Conventional assays using selective cholinesterase inhibitors have not been particularly successful as excess amounts of butyrylcholinesterase (BuChE) pose a major problem. Principal Findings Here we have estimated the levels of AChE activity in human plasma by first imm...

  3. Alteration of pulmonary function in diabetic nephropathy

    OpenAIRE

    Shafiee, Gita; Khamseh, Mohammad E.; Rezaei, Nader; Aghili, Rokhsareh; MALEK, Mojtaba

    2013-01-01

    Background Type 2 diabetes mellitus is increasing worldwide with an alarming rate. It is associated with the development of various chronic complications. The aim of this study was to explore the alteration of pulmonary function, and its association with renal complications in people with type 2 diabetes mellitus. Methods This cross-sectional study was conducted on three groups; 40 diabetic subjects without nephropathy (urinary albumin300 mg/day) .Diabetic subjects were matched to the control...

  4. Saccadic Alterations in Severe Developmental Dyslexia

    OpenAIRE

    Stefano Pensiero; Paolo Brambilla; Agostino Accardo; Paola Michieletto

    2013-01-01

    It is not sure if persons with dyslexia have ocular motor deficits in addition to their deficits in rapid visual information processing. A 15-year-old boy afflicted by severe dyslexia was submitted to saccadic eye movement recording. Neurological and ophthalmic examinations were normal apart from the presence of an esophoria for near and slightly longer latencies of pattern visual evoked potentials. Subclinical saccadic alterations were present, which could be at the basis of the reading path...

  5. Altered Gait Termination Strategies Following a Concussion

    OpenAIRE

    Buckley, Thomas A.; Munkasy, Barry A.; Tapia-Lovler, Tiffen G.; Wikstrom, Erik A.

    2013-01-01

    The purpose was to determine if planned gait termination can identify acute and lingering motor control strategy alterations in post-concussion individuals. Controls completed 2 standard gait and 5 planned gait termination trials once while concussed individuals were tested on Day-1 and Day-10 post-concussion. Dependent variables included gait velocity and normalized, relative to standard gait, peak propulsive and braking forces. Control and only Day-1 post-concussion gait velocity differed. ...

  6. Glaucoma Alters the Circadian Timing System

    OpenAIRE

    Drouyer, Elise; Dkhissi-Benyahya, Ouria; Chiquet, Christophe; WoldeMussie, Elizabeth; Ruiz, Guadalupe; Wheeler, Larry A.; Denis, Philippe; Cooper, Howard M.

    2008-01-01

    Glaucoma is a widespread ocular disease and major cause of blindness characterized by progressive, irreversible damage of the optic nerve. Although the degenerative loss of retinal ganglion cells (RGC) and visual deficits associated with glaucoma have been extensively studied, we hypothesize that glaucoma will also lead to alteration of the circadian timing system. Circadian and non-visual responses to light are mediated by a specialized subset of melanopsin expressing RGCs that provide photi...

  7. Adaptive optics without altering visual perception

    OpenAIRE

    Koenig,, I.; NW, Hart; HJ, Hofer

    2014-01-01

    Adaptive optics combined with visual psychophysics creates the potential to study the relationship between visual function and the retina at the cellular scale. This potential is hampered, however, by visual interference from the wavefront-sensing beacon used during correction. For example, we have previously shown that even a dim, visible beacon can alter stimulus perception (Hofer, H. J., Blaschke, J., Patolia, J., & Koenig, D. E. (2012). Fixation light hue bias revisited: Implications for ...

  8. Ocean acidification alters fish-jellyfish symbiosis.

    Science.gov (United States)

    Nagelkerken, Ivan; Pitt, Kylie A; Rutte, Melchior D; Geertsma, Robbert C

    2016-06-29

    Symbiotic relationships are common in nature, and are important for individual fitness and sustaining species populations. Global change is rapidly altering environmental conditions, but, with the exception of coral-microalgae interactions, we know little of how this will affect symbiotic relationships. We here test how the effects of ocean acidification, from rising anthropogenic CO2 emissions, may alter symbiotic interactions between juvenile fish and their jellyfish hosts. Fishes treated with elevated seawater CO2 concentrations, as forecast for the end of the century on a business-as-usual greenhouse gas emission scenario, were negatively affected in their behaviour. The total time that fish (yellowtail scad) spent close to their jellyfish host in a choice arena where they could see and smell their host was approximately three times shorter under future compared with ambient CO2 conditions. Likewise, the mean number of attempts to associate with jellyfish was almost three times lower in CO2-treated compared with control fish, while only 63% (high CO2) versus 86% (control) of all individuals tested initiated an association at all. By contrast, none of three fish species tested were attracted solely to jellyfish olfactory cues under present-day CO2 conditions, suggesting that the altered fish-jellyfish association is not driven by negative effects of ocean acidification on olfaction. Because shelter is not widely available in the open water column and larvae of many (and often commercially important) pelagic species associate with jellyfish for protection against predators, modification of the fish-jellyfish symbiosis might lead to higher mortality and alter species population dynamics, and potentially have flow-on effects for their fisheries. PMID:27358374

  9. Chromite alteration processes within Vourinos ophiolite

    Science.gov (United States)

    Grieco, Giovanni; Merlini, Anna

    2012-09-01

    The renewed interest in chromite ore deposits is directly related to the increase in Cr price ruled by international market trends. Chromite, an accessory mineral in peridotites, is considered to be a petrogenetic indicator because its composition reflects the degree of partial melting that the mantle experienced while producing the chromium spinel-bearing rock (Burkhard in Geochim Cosmochim Acta 57:1297-1306, 1993). However, the understanding of chromite alteration and metamorphic modification is still controversial (e.g. Evans and Frost in Geochim Cosmochim Acta 39:959-972, 1975; Burkhard in Geochim Cosmochim Acta 57:1297-1306, 1993; Oze et al. in Am J Sci 304:67-101, 2004). Metamorphic alteration leads to major changes in chromite chemistry and to the growth of secondary phases such as ferritchromite and chlorite. In this study, we investigate the Vourinos complex chromitites (from the mines of Rizo, Aetoraches, Xerolivado and Potamia) with respect to textural and chemical analyses in order to highlight the most important trend of alteration related to chromite transformation. The present study has been partially funded by the Aliakmon project in collaboration between the Public Power Corporation of Greece and Institute of Geology and Mineral Exploration of Kozani.

  10. Altered DNA methylation in PAH deficient phenylketonuria.

    Science.gov (United States)

    Dobrowolski, Steven F; Lyons-Weiler, James; Spridik, Kayla; Biery, Amy; Breck, Jane; Vockley, Jerry; Yatsenko, Svetlana; Sultana, Tamanna

    2015-01-01

    While phenylalanine (PHE) is the toxic insult in phenylketonuria (PKU), mechanisms underlying PHE toxicity remain ill-defined. Altered DNA methylation in response to toxic exposures is well-recognized. DNA methylation patterns were assessed in blood and brain from PKU patients to determine if PHE toxicity impacts methylation. Methylome assessment, utilizing methylated DNA immunoprecipitation and paired-end sequencing, was performed in DNA obtained from brain tissue of classical PKU patients, leukocytes from poorly controlled PKU patients, leukocytes from well controlled PKU patients, and appropriate control tissues. In PKU brain tissue, expression analysis determined the impact of methylation on gene function. Differential methylation was observed in brain tissue of PKU patients and expression studies identified downstream impact on gene expression. Altered patterns of methylation were observed in leukocytes of well controlled and poorly controlled patients with more extensive methylation in patients with high PHE exposure. Differential methylation of noncoding RNA genes was extensive in patients with high PHE exposure but minimal in well controlled patients. Methylome repatterning leading to altered gene expression was present in brain tissue of PKU patients, suggesting a role in neuropathology. Aberrant methylation is observed in leukocytes of PKU patients and is influenced by PHE exposure. DNA methylation may provide a biomarker relating to historic PHE exposure. PMID:25990862

  11. Alterations of lipid metabolism in Wilson disease

    Directory of Open Access Journals (Sweden)

    Stremmel Wolfgang

    2011-05-01

    Full Text Available Abstract Introduction Wilson disease (WD is an inherited disorder of human copper metabolism, characterised by accumulation of copper predominantly in the liver and brain, leading to severe hepatic and neurological disease. Interesting findings in animal models of WD (Atp7b-/- and LEC rats showed altered lipid metabolism with a decrease in the amount of triglycerides and cholesterol in the serum. However, serum lipid profile has not been investigated in large human WD patient cohorts to date. Patients and Methods This cohort study involved 251 patients examined at the Heidelberg and Dresden (Germany University Hospitals. Patients were analysed on routine follow-up examinations for serum lipid profile, including triglycerides, cholesterol, high density lipoprotein (HDL and low density lipoprotein (LDL. Data on these parameters at time of diagnosis were retrieved by chart review where available. For statistical testing, patients were subgrouped by sex, manifestation (hepatic, neurological, mixed and asymptomatic and treatment (D-penicillamine, trientine, zinc or combination. Results A significant difference in total serum cholesterol was found in patients with hepatic symptoms, which diminished under therapy. No alterations were observed for HDL, LDL and triglycerides. Conclusion Contradictory to previous reports using WD animal models (Atp7b-/- and LEC rats, the most obvious alteration in our cohort was a lower serum cholesterol level in hepatic-affected patients, which might be related to liver injury. Our data suggested unimpaired cholesterol metabolism in Wilson disease under therapy, independent of the applied medical treatment.

  12. Graviresponses of osteocytes under altered gravity

    Science.gov (United States)

    Di, S. M.; Qian, A. R.; Qu, L. N.; Zhang, W.; Wang, Z.; Ding, C.; Li, Y. H.; Ren, H. G.; Shang, P.

    2011-09-01

    Single cell was capable of sensing and responding to alterations of gravity. Osteocytes, as the most abundant cells of the bone tissue playing an important role in the bone mechanotransduction, are very sensitive to mechanical stimuli. However, the effect of altered gravity on osteocytes so far is less known according to the public papers. Further study on this issue will help to verify and develop the theory of how cells perceive and respond to gravity. It also brings new ideas to the study of space bone loss. In our study, Osteocyte-like MLO-Y4 cells were exposed to 30 parabolic flights three times on ZERO-G airbus A300 to investigate the comprehensive effect on osteocytes stimulated by hyper- and hypo-gravity forces. It showed that the cell morphology, as well as cell area and height, was not changed significantly by hyper-gravity and hypo-gravity. However, the cytoskeleton was reorganized. In flight cells, F-actin polymerization was enhanced at the cell periphery and microtubule organizing center disappeared, but no apoptotic feathers were detected. The results of western blot showed that connexin 43 (Cx43) expression was down-regulated, indicating an decrease of gap-junction. In conclusion, hyper- and hypo-gravity stimulation altered the cytoskeleton architecture and suppressed gap-junction of osteocyte-like MLO-Y4 cells.

  13. Is Obesity Associated with Altered Energy Expenditure?

    Science.gov (United States)

    Carneiro, Isabella P; Elliott, Sarah A; Siervo, Mario; Padwal, Raj; Bertoli, Simona; Battezzati, Alberto; Prado, Carla M

    2016-05-01

    Historically, obese individuals were believed to have lower energy expenditure (EE) rates than nonobese individuals (normal and overweight), which, in the long term, would contribute to a positive energy balance and subsequent weight gain. The aim of this review was to critically appraise studies that compared measures of EE and its components, resting EE (REE), activity EE (AEE), and diet-induced thermogenesis (DIT), in obese and nonobese adults to elucidate whether obesity is associated with altered EE. Contrary to popular belief, research has shown that obese individuals have higher absolute REE and total EE. When body composition (namely the metabolically active component, fat-free mass) is taken into account, these differences between obese and nonobese individuals disappear, suggesting that EE in obese individuals is not altered. However, an important question is whether AEE is lower in obese individuals because of a decrease in overall physical activity or because of less energy expended while performing physical activity. AEE and DIT could be reduced in obese individuals, mostly because of unhealthy behavior (low physical activity, higher intake of fat). However, the current evidence does not support the hypothesis that obesity is sustained by lower daily EE or REE. Future studies, comparing EE between obese and nonobese and assessing potential physiologic abnormalities in obese individuals, should be able to better answer the question of whether these individuals have altered energy metabolism. PMID:27184275

  14. Mechanism of Synthesis of Ultra-Long Single Wall Carbon Nanotubes in Arc Discharge Plasma

    Energy Technology Data Exchange (ETDEWEB)

    Keidar, Michael [George Washington University

    2013-06-23

    In this project fundamental issues related to synthesis of single wall carbon nanotubes (SWNTs), which is relationship between plasma parameters and SWNT characteristics were investigated. Given that among plasma-based techniques arc discharge stands out as very advantageous in several ways (fewer defects, high flexibility, longer lifetime) this techniques warrants attention from the plasma physics and plasma technology standpoint. Both experimental and theoretical investigations of the plasma and SWNTs synthesis were conducted. Experimental efforts focused on plasma diagnostics, measurements of nanostructures parameters, and nanoparticle characterization. Theoretical efforts focused to focus on multi-dimensional modeling of the arc discharge and single wall nanotube synthesis in arc plasmas. It was demonstrated in experiment and theoretically that controlling plasma parameters can affect nanostucture synthesis altering SWNT properties (length and diameter) and leading to synthesis of new structures such as a few-layer graphene. Among clearly identified parameters affecting synthesis are magnetic and electric fields. Knowledge of the plasma parameters and discharge characteristics is crucial for ability to control synthesis process by virtue of both magnetic and electric fields. New graduate course on plasma engineering was introduced into curriculum. 3 undergraduate students were attracted to the project and 3 graduate students (two are female) were involved in the project. Undergraduate student from Historically Black University was attracted and participated in the project during Summer 2010.

  15. Evidence of endocrine alteration in the red mullet, Mullus barbatus from the NW Mediterranean

    International Nuclear Information System (INIS)

    Red mullet (Mullus barbatus) were collected from different sampling sites (NW Mediterranean) in spring and autumn, with the aim of assessing potential alterations of the endocrine system. Alkylphenols were measured in fish bile as an indicator of estrogenic exposure. Key enzymatic activities involved in both synthesis (ovarian 17β-hydroxysteroid dehydrogenases and P450 aromatase) and metabolism of steroids were assessed together with histological alterations of the gonads. During the spring sampling, delayed gamete maturation, intersexuality, fibrosis, and depressed ovarian P450 aromatase activity were observed in organisms from the most polluted sites. During the autumn sampling, those effects were less evident, indicating that fish might be more susceptible to endocrine disrupting chemicals during the reproductive period. Nonetheless, enhanced glucuronidation of testosterone and estradiol was observed. Overall, this work provides first evidences of significant alterations in the endocrine system of red mullet from highly impacted areas in the NW Mediterranean. - Red mullet may be more susceptible to endocrine disruptors during the reproductive period

  16. Evidence of endocrine alteration in the red mullet, Mullus barbatus from the NW Mediterranean

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Skilton, Rebeca [Department of Environmental Chemistry, IIQAB-CSIC, Jordi Girona 18, 08034 Barcelona (Spain); Lavado, Ramon [Department of Environmental Chemistry, IIQAB-CSIC, Jordi Girona 18, 08034 Barcelona (Spain); Thibaut, Remi [Department of Environmental Chemistry, IIQAB-CSIC, Jordi Girona 18, 08034 Barcelona (Spain); Minier, Christophe [Laboratoire d' Ecotoxicologie, Universite du Havre, 25 rue Philippe Lebon, B.P. 540, F-76058 Le Havre (France); Porte, Cinta [Department of Environmental Chemistry, IIQAB-CSIC, Jordi Girona 18, 08034 Barcelona (Spain)]. E-mail: cpvqam@cid.csic.es

    2006-05-15

    Red mullet (Mullus barbatus) were collected from different sampling sites (NW Mediterranean) in spring and autumn, with the aim of assessing potential alterations of the endocrine system. Alkylphenols were measured in fish bile as an indicator of estrogenic exposure. Key enzymatic activities involved in both synthesis (ovarian 17{beta}-hydroxysteroid dehydrogenases and P450 aromatase) and metabolism of steroids were assessed together with histological alterations of the gonads. During the spring sampling, delayed gamete maturation, intersexuality, fibrosis, and depressed ovarian P450 aromatase activity were observed in organisms from the most polluted sites. During the autumn sampling, those effects were less evident, indicating that fish might be more susceptible to endocrine disrupting chemicals during the reproductive period. Nonetheless, enhanced glucuronidation of testosterone and estradiol was observed. Overall, this work provides first evidences of significant alterations in the endocrine system of red mullet from highly impacted areas in the NW Mediterranean. - Red mullet may be more susceptible to endocrine disruptors during the reproductive period.

  17. Iceland as a Model for Chemical Alteration on Mars

    Science.gov (United States)

    Bishop, Janice L.; Schiffman, P.; Murad, E.; Southard, R.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    Subglacial volcanic activity on Iceland has led to the formation of a variety of silicate and iron oxide-rich alteration products that may serve as a model for chemical alteration on Mars. Multiple palagonitic tuffs, altered pillow lavas, hydrothermal springs and alteration at glacial run-off streams were observed during a recent field trip in Iceland. Formation of alteration products and ferrihydrite in similar environments on Mars may have contributed to the ferric oxide-rich surface material there. The spectral and chemical properties of Icelandic alteration products and ferrihydrites are presented here.

  18. Enamel alteration following tooth bleaching and remineralization.

    Science.gov (United States)

    Coceska, Emilija; Gjorgievska, Elizabeta; Coleman, Nichola J; Gabric, Dragana; Slipper, Ian J; Stevanovic, Marija; Nicholson, John W

    2016-06-01

    The purpose of this study was to compare the effects of professional tooth whitening agents containing highly concentrated hydrogen peroxide (with and without laser activation), on the enamel surface; and the potential of four different toothpastes to remineralize any alterations. The study was performed on 50 human molars, divided in two groups: treated with Opalescence(®) Boost and Mirawhite(®) Laser Bleaching. Furthermore, each group was divided into five subgroups, a control one and 4 subgroups remineralized with: Mirasensitive(®) hap+, Mirawhite(®) Gelleѐ, GC Tooth Mousse™ and Mirafluor(®) C. The samples were analysed by SEM/3D-SEM-micrographs, SEM/EDX-qualitative analysis and SEM/EDX-semiquantitative analysis. The microphotographs show that both types of bleaching cause alterations: emphasized perikymata, erosions, loss of interprizmatic substance; the laser treatment is more aggressive and loss of integrity of the enamel is determined by shearing off the enamel rods. In all samples undergoing remineralization deposits were observed, those of toothpastes based on calcium phosphate technologies seem to merge with each other and cover almost the entire surface of the enamel. Loss of integrity and minerals were detected only in the line-scans of the sample remineralized with GC Tooth Mousse™. The semiquantitative EDX analysis of individual elements in the surface layer of the enamel indicates that during tooth-bleaching with HP statistically significant loss of Na and Mg occurs, whereas the bleaching in combination with a laser leads to statistically significant loss of Ca and P. The results undoubtedly confirm that teeth whitening procedures lead to enamel alterations. In this context, it must be noted that laser bleaching is more aggressive for dental substances. However, these changes are reversible and can be repaired by application of remineralization toothpastes. PMID:27197087

  19. Enabling Technologies for the Future of Chemical Synthesis.

    Science.gov (United States)

    Fitzpatrick, Daniel E; Battilocchio, Claudio; Ley, Steven V

    2016-03-23

    Technology is evolving at breakneck pace, changing the way we communicate, travel, find out information, and live our lives. Yet chemistry as a science has been slower to adapt to this rapidly shifting world. In this Outlook we use highlights from recent literature reports to describe how progresses in enabling technologies are altering this trend, permitting chemists to incorporate new advances into their work at all levels of the chemistry development cycle. We discuss the benefits and challenges that have arisen, impacts on academic-industry relationships, and future trends in the area of chemical synthesis. PMID:27163040

  20. Ethics of Chemical Synthesis

    Directory of Open Access Journals (Sweden)

    Joachim Schummer

    2001-10-01

    Full Text Available Unlike other branches of science, the scientific products of synthetic chemistry are not only ideas but also new substances that change our material world, for the benefit or harm of living beings. This paper provides for the first time a systematical analysis of moral issues arising from chemical synthesis, based on concepts of responsibility and general morality. Topics include the questioning of moral neutrality of chemical synthesis as an end in itself, chemical weapons research, moral objections against improving material conditions of life by chemical means, and freedom of research. The paper aims at providing both a sound basis for moral judgements of chemistry in a public discourse and a framework for chemists to reflect on the moral relevance of their activity.

  1. Expanding the modern synthesis.

    Science.gov (United States)

    Wallace, Rodrick

    2010-10-01

    The Modern Evolutionary Synthesis formalizes the role of variation, heredity, differential reproduction and mutation in population genetics. Here we explore a mathematical structure, based on the asymptotic limit theorems of communication theory, that instantiates the punctuated dynamic relations of organisms with their embedding environments, including the possibility of the transfer of heritage information between different classes of organism. The approach applies a standard coevolutionary argument to genes, environment, and gene expression reconfigured as interacting information sources. In essence, we provide something of a formal roadmap for the modernization of the Modern Synthesis, making applications to both relatively rapid evolutionary punctuated equilibrium and to the conservation of ecological interactions across deep evolutionary time. PMID:20965439

  2. Benzoylurea Chitin Synthesis Inhibitors.

    Science.gov (United States)

    Sun, Ranfeng; Liu, Chunjuan; Zhang, Hao; Wang, Qingmin

    2015-08-12

    Benzoylurea chitin synthesis inhibitors are widely used in integrated pest management (IPM) and insecticide resistance management (IRM) programs due to their low toxicity to mammals and predatory insects. In the past decades, a large number of benzoylurea derivatives have been synthesized, and 15 benzoylurea chitin synthesis inhibitors have been commercialized. This review focuses on the history of commercial benzolyphenylureas (BPUs), synthetic methods, structure-activity relationships (SAR), action mechanism research, environmental behaviors, and ecotoxicology. Furthermore, their disadvantages of high risk to aquatic invertebrates and crustaceans are pointed out. Finally, we propose that the para-substituents at anilide of benzoylphenylureas should be the functional groups, and bipartite model BPU analogues are discussed in an attempt to provide new insight for future development of BPUs. PMID:26168369

  3. Prebiotic synthesis of histidine

    Science.gov (United States)

    Shen, C.; Yang, L.; Miller, S. L.; Oro, J.

    1990-01-01

    The prebiotic formation of histidine (His) has been accomplished experimentally by the reaction of erythrose with formamidine followed by a Strecker synthesis. In the first step of this reaction sequence, the formation of imidazole-4-acetaldehyde took place by the condensation of erythrose and formamidine, two compounds that are known to be formed under prebiotic conditions. In a second step, the imidazole-4-acetaldehyde was converted to His, without isolation of the reaction products by adding HCN and ammonia to the reaction mixture. LC, HPLC, thermospray liquid chromatography-mass spectrometry, and tandem mass spectrometry were used to identify the product, which was obtained in a yield of 3.5% based on the ratio of His/erythrose. This is a new chemical synthesis of one of the basic amino acids which had not been synthesized prebiotically until now.

  4. Synthesis of approximation errors

    Energy Technology Data Exchange (ETDEWEB)

    Bareiss, E.H.; Michel, P.

    1977-07-01

    A method is developed for the synthesis of the error in approximations in the large of regular and irregular functions. The synthesis uses a small class of dimensionless elementary error functions which are weighted by the coefficients of the expansion of the regular part of the function. The question is answered whether a computer can determine the analytical nature of a solution by numerical methods. It is shown that continuous least-squares approximations of irregular functions can be replaced by discrete least-squares approximation and how to select the discrete points. The elementary error functions are used to show how the classical convergence criterions can be markedly improved. There are eight numerical examples included, 30 figures and 74 tables.

  5. Total synthesis of (-)-spinosyn A.

    Science.gov (United States)

    Mergott, Dustin J; Frank, Scott A; Roush, William R

    2004-08-17

    A convergent, highly stereoselective total synthesis of (-)-spinosyn A (1) is described. Key features of the synthesis include the transannular Diels-Alder reaction of macrocyclic pentaene 11 and the transannular Morita-Baylis-Hillman cyclization of 12 that generates tetracycle 26. The total synthesis of (-)-spinosyn A was completed by a sequence involving the highly beta-selective glycosidation reaction of 13 and glycosyl imidate 30. PMID:15173590

  6. Alterations of 5-Hydroxymethylcytosine in Human Cancers

    Directory of Open Access Journals (Sweden)

    Ali Yesilkanal

    2013-06-01

    Full Text Available Prior to 2009, 5-methylcytosine (5-mC was thought to be the only biologically significant cytosine modification in mammalian DNA. With the discovery of the TET enzymes, which convert 5-methylcytosine (5-mC to 5-hydroxymethylcytosine (5-hmC, however, intense interest has emerged in determining the biological function of 5-hmC. Here, we review the techniques used to study 5-hmC and evidence that alterations to 5-hmC physiology play a functional role in the molecular pathogenesis of human cancers.

  7. Genitourinary echography alterations in the pseudoxanthoma elasticum

    International Nuclear Information System (INIS)

    This is the case of a black male sex patient aged 13 diagnosed with elastic. Renal and testicular ultrasonographic study showed echo-refractive images in testes and kidneys without neither acoustic shadow nor alterations of renal function or of the urinary sediment. There was not a family history of cutaneous lesions related with this entity. These renal and testicular findings have been documented in the medical literature, thus, authors recommended that its popularization is interesting since it has been proposed that they are part of the disease phenotype

  8. SON68 glass alteration enhanced by magnetite

    International Nuclear Information System (INIS)

    This paper reports experimental and modeling results of SON68 glass / magnetite interactions while in contact with synthetic groundwater from a clay environment. It is shown that magnetite enhances glass alteration, first by the sorption of Si released from the glass onto magnetite surfaces, then by a second process that could be the precipitation of an iron silicate mineral or the transformation of magnetite into a more reactive phase like hematite or goethite. This study globally suggests a detrimental effect of magnetite on the long-term durability of nuclear glass in geological disposal conditions. (authors)

  9. Microwave Multicomponent Synthesis

    OpenAIRE

    Helmut M Hügel

    2009-01-01

    In the manner that very important research is often performed by multidisciplinary research teams, the applications of multicomponent reactions involving the combination of multiple starting materials with different functional groups leading to the higher efficiency and environmentally friendly construction of multifunctional/complex target molecules is growing in importance. This review will explore the advances and advantages in microwave multicomponent synthesis (MMS) that have been achiev...

  10. Enzymatic synthesis of vanillin

    OpenAIRE

    van den Heuvel, RHH; Fraaije, MW; Laane, C; van Berkel, WJH; Heuvel, Robert H.H. van den; van Berkel, Willem J. H.

    2001-01-01

    Due to increasing interest in natural vanillin, two enzymatic routes for the synthesis of vanillin were developed. The flavoprotein vanillyl alcohol oxidase (VAO) acts on a wide range of phenolic compounds and converts both creosol and vanillylamine to vanillin with high yield. The VAO-mediated conversion of creosol proceeds via a two-step process in which the initially formed vanillyl alcohol is further oxidized to vanillin. Catalysis is limited by the formation of an abortive complex betwee...

  11. Total Synthesis of Millingtonine.

    Science.gov (United States)

    Brown, Patrick D; Lawrence, Andrew L

    2016-07-11

    Millingtonine is a glycosidic alkaloid that exists as a pair of pseudo-enantiomeric diastereomers. Consideration of the likely biosynthetic origins of this unusual natural product has resulted in the development of a seven-step total synthesis. Results from this synthetic work provide evidence in support of a proposed network of biosynthetic pathways that can account for the formation of several phenylethanoid natural products. PMID:27249628

  12. Phase contrast image synthesis

    DEFF Research Database (Denmark)

    Glückstad, J.

    1996-01-01

    A new method is presented for synthesizing arbitrary intensity patterns based on phase contrast imaging. The concept is grounded on an extension of the Zernike phase contrast method into the domain of full range [0; 2 pi] phase modulation. By controlling the average value of the input phase...... function and by choosing appropriate phase retardation at the phase contrast filter, a pure phase to intensity imaging is accomplished. The method presented is also directly applicable in dark field image synthesis....

  13. Stochastic component mode synthesis

    OpenAIRE

    Bah, Mamadou T.; Nair, Prasanth B.; Bhaskar, Atul; Keane, Andy J.

    2003-01-01

    In this paper, a stochastic component mode synthesis method is developed for the dynamic analysis of large-scale structures with parameter uncertainties. The main idea is to represent each component displacement using a subspace spanned by a set of stochastic basis vectors in the same fashion as in stochastic reduced basis methods [1, 2]. These vectors represent however stochastic modes in contrast to the deterministic modes used in conventional substructuring methods [3]. The Craig-Bampton r...

  14. Total synthesis of teixobactin.

    Science.gov (United States)

    Jin, Kang; Sam, Iek Hou; Po, Kathy Hiu Laam; Lin, Du'an; Ghazvini Zadeh, Ebrahim H; Chen, Sheng; Yuan, Yu; Li, Xuechen

    2016-01-01

    To cope with the global bacterial multidrug resistance, scientific communities have devoted significant efforts to develop novel antibiotics, particularly those with new modes of actions. Teixobactin, recently isolated from uncultured bacteria, is considered as a promising first-in-class drug candidate for clinical development. Herein, we report its total synthesis by a highly convergent Ser ligation approach and this strategy allows us to prepare several analogues of the natural product. PMID:27484680

  15. HNAB: synthesis and characterization

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, D.M.

    1976-05-01

    The laboratory and pilot-plant scale synthesis of hexanitroazobenzene (HNAB) are detailed. Some of its physical, chemical, and explosive properties are presented and discussed. Among these are included polymorphic forms, thermal behavior, spectra, solubility, compatibility, toxicity, sensitivity to gap test, detonation velocity and pressure, impact sensitivity, and explosive classification. Finally, some alternate syntheses of HNAB and its intermediates are considered; some of these were successful and some were not.

  16. Total synthesis of ochnaflavone

    OpenAIRE

    Monica M. Ndoile; van Heerden, Fanie R

    2013-01-01

    The first total syntheses of ochnaflavone, an asymmetric biflavone consisting of apigenin and luteolin moieties, and the permethyl ether of 2,3,2'',3''-tetrahydroochnaflavone have been achieved. The key steps in the synthesis of ochnaflavone were the formation of a diaryl ether and ring cyclization of an ether-linked dimeric chalcone to assemble the two flavone nuclei. Optimal experimental conditions for the oxidative cyclization to form ochnaflavone were established.

  17. Total synthesis of ochnaflavone

    Directory of Open Access Journals (Sweden)

    Monica M. Ndoile

    2013-07-01

    Full Text Available The first total syntheses of ochnaflavone, an asymmetric biflavone consisting of apigenin and luteolin moieties, and the permethyl ether of 2,3,2'',3''-tetrahydroochnaflavone have been achieved. The key steps in the synthesis of ochnaflavone were the formation of a diaryl ether and ring cyclization of an ether-linked dimeric chalcone to assemble the two flavone nuclei. Optimal experimental conditions for the oxidative cyclization to form ochnaflavone were established.

  18. Towards a new Synthesis

    OpenAIRE

    Foss, Nicolai J.; Klein, Peter G.; Kor, Yasemin Y.; Joseph T. Mahoney

    2006-01-01

    This paper maintains that the consistent application of subjectivism helps to reconcile contemporary entrepreneurship theory with strategic management research in general, and the resource−based view in particular. The paper synthesizes theoretical insights from Austrian economics and Penrose’s (1959) resources approach, arguing that entrepreneurship is inherently subjective and firm specific. This new synthesis describes how entrepreneurship is manifested in teams, and is driven by both hete...

  19. Combinatorial materials synthesis

    OpenAIRE

    Ichiro Takeuchi; Jochen Lauterbach; Michael J. Fasolka

    2005-01-01

    The pace at which major technological changes take place is often dictated by the rate at which new materials are discovered, and the timely arrival of new materials has always played a key role in bringing advances to our society. It is no wonder then that the so-called combinatorial or high-throughput strategy has been embraced by practitioners of materials science in virtually every field. High-throughput experimentation allows simultaneous synthesis and screening of large arrays of differ...

  20. Phase contrast image synthesis

    DEFF Research Database (Denmark)

    Glückstad, J.

    A new method is presented for synthesizing arbitrary intensity patterns based on phase contrast imaging. The concept is grounded on an extension of the Zernike phase contrast method into the domain of full range [0; 2 pi] phase modulation. By controlling the average value of the input phase funct...... function and by choosing appropriate phase retardation at the phase contrast filter, a pure phase to intensity imaging is accomplished. The method presented is also directly applicable in dark field image synthesis....

  1. 28 CFR 36.404 - Alterations: Elevator exemption.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Alterations: Elevator exemption. 36.404... Alterations: Elevator exemption. (a) This section does not require the installation of an elevator in an... facility has an elevator....

  2. Methods of component mode synthesis

    Science.gov (United States)

    Craig, R. R., Jr.

    1977-01-01

    A generalized substructure coupling, or component mode synthesis, procedure is described. Specific methods, applications, and such special topics as damping and experimental verification are surveyed.

  3. Radiochemical synthesis of etomoxir

    International Nuclear Information System (INIS)

    Sodium 2-{6-(4-chlorophenoxy)hexyl}oxirane-2-carboxylate (Etomoxir) inhibits transport of fatty acids via the carnitine shuttle into mitochondria of muscle cells and prevents long chain fatty acids from providing energy through β-oxidation especially for muscle contraction. The objective of this synthesis is to develop a method for radioiodination of Etomoxir in order to explore its potential in diagnostic metabolic studies and molecular imaging. Thus, a method is described for the radiochemical synthesis and purification of ethyl 2-{6-(4-[131I]iodophenoxy)hexyl}oxirane-2-carboxylate (3) and 2-{6-(4-[131I]iodo-phenoxy)hexyl}oxirane-2-carboxylic acid (4). For the synthesis of these new agents, ethyl 2-{6-(4-bromophenoxy)hexyl}oxirane-2-carboxylate (1) and 2-{6-(4-bromophenoxy)hexyl}oxirane-2-carboxylic acid (2) were refluxed with [131I]NaI in the presence of anhydrous acetone at a temperature of 80 oC and 90 oC for a period of 3-4 hours, respectively. The method of radiolabeling, based on the nucleophilic exchange reaction, resulted in a radiochemical yield of 43% and 67% for compounds 3 and 4, respectively. This paper reports on the labeling of etomoxir with radioiodine as 124I labeled etomoxir may be of great importance in molecular imaging.

  4. Chemistry of Ammonothermal Synthesis

    Directory of Open Access Journals (Sweden)

    Theresia M. M. Richter

    2014-02-01

    Full Text Available Ammonothermal synthesis is a method for synthesis and crystal growth suitable for a large range of chemically different materials, such as nitrides (e.g., GaN, AlN, amides (e.g., LiNH2, Zn(NH22, imides (e.g., Th(NH2, ammoniates (e.g., Ga(NH33F3, [Al(NH36]I3 · NH3 and non-nitrogen compounds like hydroxides, hydrogen sulfides and polychalcogenides (e.g., NaOH, LiHS, CaS, Cs2Te5. In particular, large scale production of high quality crystals is possible, due to comparatively simple scalability of the experimental set-up. The ammonothermal method is defined as employing a heterogeneous reaction in ammonia as one homogenous fluid close to or in supercritical state. Three types of milieus may be applied during ammonothermal synthesis: ammonobasic, ammononeutral or ammonoacidic, evoked by the used starting materials and mineralizers, strongly influencing the obtained products. There is little known about the dissolution and materials transport processes or the deposition mechanisms during ammonothermal crystal growth. However, the initial results indicate the possible nature of different intermediate species present in the respective milieus.

  5. Gold Nanoparticle Microwave Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Krantz, Kelsie E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Christian, Jonathan H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coopersmith, Kaitlin [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Murph, Simona H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-27

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, a reduction in reaction time from 10 minutes to 1 minute, maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  6. Integrated methanol synthesis

    International Nuclear Information System (INIS)

    This invention concerns a plant for methanol manufacture from gasified coal, particularly using nuclear power. In order to reduce the cost of the hydrogen circuits, the methanol synthesis is integrated in the coal gasification plant. The coal used is gasified with hydration by means of hydrogen and the crude gas emerging, after cooling and separating the carbon dioxide and hydrogen sulphide, is mixed with the synthetic gas leaving the methane cracking furnace. This mixture is taken to the methanol synthesis and more than 90% is converted into methanol in one pass. The gas mixture remaning after condensation and separation of methanol is decomposed into three fractions in low temperature gas decomposition with a high proportion of unconverted carbon monoxide. The flow of methane is taken to the cracking furnace with steam, the flow of hydrogen is taken to the hydrating coal gasifier, and the flow of carbon monoxide is taken to the methanol synthesis. The heat required for cracking the methane can either be provided by a nuclear reactor or by the coke left after hydrating gasification. (orig./RB)

  7. Time is the key Music and Altered States of Consciusness

    OpenAIRE

    Fachner, Jörg

    2011-01-01

    Introduction: In this chapter, I will summarize the literature on how music and altered states of consciousness (ASC) are connected. Essential aspects include induction and expression of emotions and rhythmic body movements to music and how an altered experience of music is connected to states of altered temporality. Winkelman (2000) stressed the human capacity for experiencing ASC as a fundamental biological function. Studies on brain functions of altered music experience a...

  8. Maternal vitamin D deficiency alters fetal brain development in the BALB/c mouse.

    Science.gov (United States)

    Hawes, Jazmin E; Tesic, Dijana; Whitehouse, Andrew J; Zosky, Graeme R; Smith, Jeremy T; Wyrwoll, Caitlin S

    2015-06-01

    Prenatal exposure to vitamin D is thought to be critical for optimal fetal neurodevelopment, yet vitamin D deficiency is apparent in a growing proportion of pregnant women. The aim of this study was to determine whether a mouse model of vitamin D-deficiency alters fetal neurodevelopment. Female BALB/c mice were placed on either a vitamin D control (2,195 IU/kg) or deficient (0 IU/kg) diet for 5 weeks prior to and during pregnancy. Fetal brains were collected at embryonic day (E) 14.5 or E17.5 for morphological and gene expression analysis. Vitamin D deficiency during pregnancy reduced fetal crown-rump length and head size. Moreover, lateral ventricle volume was reduced in vitamin D-deficient foetuses. Expression of neurotrophin genes brain-derived neurotrophic factor (Bdnf) and transforming growth factor-β1 (Tgf-β1) was altered, with Bdnf reduced at E14.5 and increased at E17.5 following vitamin D deficiency. Brain expression of forkhead box protein P2 (Foxp2), a gene known to be important in human speech and language, was also altered. Importantly, Foxp2 immunoreactive cells in the developing cortex were reduced in vitamin D-deficient female foetuses. At E17.5, brain tyrosine hydroxylase (TH) gene expression was reduced in females, as was TH protein localization (to identify dopamine neurons) in the substantia nigra of vitamin D-deficient female foetuses. Overall, we show that prenatal vitamin D-deficiency leads to alterations in fetal mouse brain morphology and genes related to neuronal survival, speech and language development, and dopamine synthesis. Vitamin D appears to play an important role in mouse neurodevelopment. PMID:25753408

  9. Female genital alteration: a compromise solution.

    Science.gov (United States)

    Arora, Kavita Shah; Jacobs, Allan J

    2016-03-01

    Despite 30 years of advocacy, the prevalence of non-therapeutic female genital alteration (FGA) in minors is stable in many countries. Educational efforts have minimally changed the prevalence of this procedure in regions where it has been widely practiced. In order to better protect female children from the serious and long-term harms of some types of non-therapeutic FGA, we must adopt a more nuanced position that acknowledges a wide spectrum of procedures that alter female genitalia. We offer a revised categorisation for non-therapeutic FGA that groups procedures by effect and not by process. Acceptance of de minimis procedures that generally do not carry long-term medical risks is culturally sensitive, does not discriminate on the basis of gender, and does not violate human rights. More morbid procedures should not be performed. However, accepting de minimis non-therapeutic f FGA procedures enhances the effort of compassionate practitioners searching for a compromise position that respects cultural differences but protects the health of their patients. PMID:26902479

  10. Origins of altered reinforcement effects in ADHD

    Directory of Open Access Journals (Sweden)

    Tripp Gail

    2009-02-01

    Full Text Available Abstract Attention-deficit/hyperactivity disorder (ADHD, characterized by hyperactivity, impulsiveness and deficient sustained attention, is one of the most common and persistent behavioral disorders of childhood. ADHD is associated with catecholamine dysfunction. The catecholamines are important for response selection and memory formation, and dopamine in particular is important for reinforcement of successful behavior. The convergence of dopaminergic mesolimbic and glutamatergic corticostriatal synapses upon individual neostriatal neurons provides a favorable substrate for a three-factor synaptic modification rule underlying acquisition of associations between stimuli in a particular context, responses, and reinforcers. The change in associative strength as a function of delay between key stimuli or responses, and reinforcement, is known as the delay of reinforcement gradient. The gradient is altered by vicissitudes of attention, intrusions of irrelevant events, lapses of memory, and fluctuations in dopamine function. Theoretical and experimental analyses of these moderating factors will help to determine just how reinforcement processes are altered in ADHD. Such analyses can only help to improve treatment strategies for ADHD.

  11. Aqueous Alteration Mineralogy in CM Carbonaceous Chondrites

    Science.gov (United States)

    Chokai, J.; Zolensky, M.; Le, L.; Nakamura, K.; Mikouchi, T.; Monkawa, A.; Koizumi, E.; Miyamoto, M.

    2004-01-01

    Iron-nickel sulfides are found in most or all solar system environments, and are probably the only minerals found in all extraterrestrial materials on hand. Despite the ubiquity, they have not received the attention they deserve. The most common Fe-Ni sulfides in chondrites are troilite (FeS), pyrrhotite (Fe1- XS) and pentlandite (Fe,Ni)9S8. Troilite is believed to have resulted from sulfidation of metal (Fe-Ni) grains in an H2Scontaining environment. Pyrrhotite is produced when friable troilite grains, which are exfoliated from the metal nucleus, are submitted to continued sulfidation [1]. Some asteroids are known to have experienced aqueous alteration, forming products including new generations of sulfides (pyrrhotite and pentlandite). Pentlandite in particular is known to form during such alteration [1]. However, experimental work by Lauretta has indicated that pentlandite may also have been formed during the initial sulfidation process [2], due to the faster diffusion rate of nickel into the forming sulfide, as compared to iron. Finally, there is considerable evidence [1,3&4] for a family of phases intermediate between pyrrhotite and pentlandite, following the trend of the high temperature monosulfide solid solution [5], something not encountered in terrestrial rocks.

  12. Origins of altered reinforcement effects in ADHD.

    Science.gov (United States)

    Johansen, Espen Borgå; Killeen, Peter R; Russell, Vivienne A; Tripp, Gail; Wickens, Jeff R; Tannock, Rosemary; Williams, Jonathan; Sagvolden, Terje

    2009-01-01

    Attention-deficit/hyperactivity disorder (ADHD), characterized by hyperactivity, impulsiveness and deficient sustained attention, is one of the most common and persistent behavioral disorders of childhood. ADHD is associated with catecholamine dysfunction. The catecholamines are important for response selection and memory formation, and dopamine in particular is important for reinforcement of successful behavior. The convergence of dopaminergic mesolimbic and glutamatergic corticostriatal synapses upon individual neostriatal neurons provides a favorable substrate for a three-factor synaptic modification rule underlying acquisition of associations between stimuli in a particular context, responses, and reinforcers. The change in associative strength as a function of delay between key stimuli or responses, and reinforcement, is known as the delay of reinforcement gradient. The gradient is altered by vicissitudes of attention, intrusions of irrelevant events, lapses of memory, and fluctuations in dopamine function. Theoretical and experimental analyses of these moderating factors will help to determine just how reinforcement processes are altered in ADHD. Such analyses can only help to improve treatment strategies for ADHD. PMID:19226460

  13. Obesity Promotes Alterations in Iron Recycling

    Directory of Open Access Journals (Sweden)

    Marta Citelli

    2015-01-01

    Full Text Available Hepcidin is a key hormone that induces the degradation of ferroportin (FPN, a protein that exports iron from reticuloendothelial macrophages and enterocytes. The aim of the present study was to experimentally evaluate if the obesity induced by a high-fat diet (HFD modifies the expression of FPN in macrophages and enterocytes, thus altering the iron bioavailability. In order to directly examine changes associated with iron metabolism in vivo, C57BL/6J mice were fed either a control or a HFD. Serum leptin levels were evaluated. The hepcidin, divalent metal transporter-1 (DMT1, FPN and ferritin genes were analyzed by real-time polymerase chain reaction. The amount of iron present in both the liver and spleen was determined by flame atomic absorption spectrometry. Ferroportin localization within reticuloendothelial macrophages was observed by immunofluorescence microscopy. Obese animals were found to exhibit increased hepcidin gene expression, while iron accumulated in the spleen and liver. They also exhibited changes in the sublocation of splenic cellular FPN and a reduction in the FPN expression in the liver and the spleen, while no changes were observed in enterocytes. Possible explanations for the increased hepcidin expression observed in HFD animals may include: increased leptin levels, the liver iron accumulation or endoplasmic reticulum (ER stress. Together, the results indicated that obesity promotes changes in iron bioavailability, since it altered the iron recycling function.

  14. Neurobiological alterations in alcohol addiction: a review.

    Science.gov (United States)

    Erdozain, Amaia M; Callado, Luis F

    2014-01-01

    The exact mechanism by which ethanol exerts its effects on the brain is still unknown. However, nowadays it is well known that ethanol interacts with specific neuronal membrane proteins involved in signal transmission, resulting in changes in neural activity. In this review different neurochemical alterations produced by ethanol are described. Primarily, ethanol interacts with two membrane receptors: GABAA and NMDA ion channel receptors. Ethanol enhances the GABA action and antagonizes glutamate action, therefore acting as a CNS depressant. In addition, ethanol affects most other neurochemical and endocrine systems. In regard to the brain reward system, both dopaminergic and opioid system are affected by this drug. Furthermore, the serotonergic, noradrenergic, corticotropin-releasing factor and cannabinoid systems seem to play an important role in the neurobiology of alcoholism. At last but not least, ethanol can also modulate cytoplasmic components, including the second messengers. We also review briefly the different actual and putative pharmacological treatments for alcoholism, based on the alterations produced by this drug. PMID:25578004

  15. Morphology of altered layers of glasses

    International Nuclear Information System (INIS)

    The alteration of the french nuclear waste glass R7T7 has been studied through chemical analysis, thermo-poro-metry and X-ray scattering. Pseudo-dynamic leaching was used, with daily renewal of the leaching solution. The behavior of the R77 glass has been compared to cesium borosilicate glasses with small amounts of Ca and Zr added. As compared to these simplified compositions, the R7T7 glass has a quasi-congruent leaching of Na, B and Si and strongly retains Ca and Zr. The altered layers are very porous (porosity > 40% ). The pore size increases with time to reach a constant value that is independent of the nature of the glass but that strongly depends on the method used for leaching. The pore radii are about 4 nm in pseudo-dynamic mode and 2 nm in static conditions. X-ray scattering indicate that the pores are compact with a sharp interface. Their origin is related to the quasi-equilibrium reaction of hydrolysis redeposition of silica. (authors)

  16. DNA-content and synthesis rate in human melanoma cells in vitro after hyperthermia and radiation

    International Nuclear Information System (INIS)

    Human melanoma cells were cultured over 168 hours. DNA-content and 3H-thymidine incorporation were measured after 800 R and hyperthermia of 400C and 440C for 3 and 6 hours. An early and a late effect could be distinguished. 3 and 6 hours after irradiation alone no alteration of DNA-synthesis was observed. After heat treatment at 400C for 6 hours the DNA-synthesis was increased immediately. 420C and 440C deminished the rate of DNA-synthesis. The combined treatment (heat and irradiation) suppressed the overshooting rate of DNA-synthesis. Accordingly after heat treatment at 400C for 6 hours the DNA-content was higher than the controls and the 3 hours-400C treated cultures measured over a period of 48 hours. Thereafter the DNA-content showed little or no alterations compared with the controls. The heat treatment at 440C reduced the DNA-content heavily, followed by a relative increase at 120 hours. The DNA-synthesis rate showed the same effect. The combined treatment suppressed this late increase. However, 24 hours after combined treatment the incorporation of thymidine into the DNA was higher at 440C-6 than 440C-3 hours, 40C-3 hours, than 400C-6 hours, although the DNA-content was very low. The results show synergistic effects of hyperthermia and radiation on the DNA-synthesis and content if one considers the effects at the later periods (120-168 hours). However, a stimulating effect is found on the DNA-synthesis if the melanoma cells are incubated at 400C for 6 hours. (orig.)

  17. Response of rat brain protein synthesis to ethanol and sodium barbital

    International Nuclear Information System (INIS)

    Central nervous system (CNS) depressants such as ethanol and barbiturates under acute or chronic conditions can induce changes in rat brain protein synthesis. While these data demonstrate the individual effects of drugs on protein synthesis, the response of brain protein synthesis to alcohol-drug interactions is not known. The goal of the present study was to determine the individual and combined effects of ethanol and sodium barbital on brain protein synthesis and gain an understanding of the mechanisms by which these alterations in protein synthesis are produced. Specifically, the in vivo and in vitro effects of sodium barbital (one class of barbiturates which is not metabolized by the hepatic tissue) were examined on brain protein synthesis in rats made physically dependent upon ethanol. Using cell free brain polysomal systems isolated from Control, Ethanol and 24 h Ethanol Withdrawn rats, data show that sodium barbital, when intubated intragastrically, inhibited the time dependent incorporation of 14C) leucine into protein by all three groups of ribosomes. Under these conditions, the Ethanol Withdrawn group displayed the largest inhibition of the 14C) leucine incorporation into protein when compared to the Control and Ethanol groups. In addition, sodium barbital when added at various concentrations in vitro to the incubation medium inhibited the incorporation of 14C) leucine into protein by Control and Ethanol polysomes. The inhibitory effects were also obtained following preincubation of ribosomes in the presence of barbital but not cycloheximide. Data suggest that brain protein synthesis, specifically brain polysomes, through interaction with ethanol or barbital are involved in the functional development of tolerance. These interactions may occur through proteins or polypeptide chains or alterations in messenger RNA components associated with the ribosomal units

  18. Hydrothermal organic synthesis experiments

    Science.gov (United States)

    Shock, Everett L.

    1992-01-01

    The serious scientific debate about spontaneous generation which raged for centuries reached a climax in the nineteenth century with the work of Spallanzani, Schwann, Tyndall, and Pasteur. These investigators demonstrated that spontaneous generation from dead organic matter does not occur. Although no aspects of these experiments addressed the issue of whether organic compounds could be synthesized abiotically, the impact of the experiments was great enough to cause many investigators to assume that life and its organic compounds were somehow fundamentally different than inorganic compounds. Meanwhile, other nineteenth-century investigators were showing that organic compounds could indeed be synthesized from inorganic compounds. In 1828 Friedrich Wohler synthesized urea in an attempt to form ammonium cyanate by heating a solution containing ammonia and cyanic acid. This experiment is generally recognized to be the first to bridge the artificial gap between organic and inorganic chemistry, but it also showed the usefulness of heat in organic synthesis. Not only does an increase in temperature enhance the rate of urea synthesis, but Walker and Hambly showed that equilibrium between urea and ammonium cyanate was attainable and reversible at 100 C. Wohler's synthesis of urea, and subsequent syntheses of organic compounds from inorganic compounds over the next several decades dealt serious blows to the 'vital force' concept which held that: (1) organic compounds owe their formation to the action of a special force in living organisms; and (2) forces which determine the behavior of inorganic compounds play no part in living systems. Nevertheless, such progress was overshadowed by Pasteur's refutation of spontaneous generation which nearly extinguished experimental investigations into the origins of life for several decades. Vitalism was dealt a deadly blow in the 1950's with Miller's famous spark-discharge experiments which were undertaken in the framework of the Oparin

  19. Implications of Altered Glutathione Metabolism in Aspirin-Induced Oxidative Stress and Mitochondrial Dysfunction in HepG2 Cells

    OpenAIRE

    Raza, Haider; John, Annie

    2012-01-01

    We have previously reported that acetylsalicylic acid (aspirin, ASA) induces cell cycle arrest, oxidative stress and mitochondrial dysfunction in HepG2 cells. In the present study, we have further elucidated that altered glutathione (GSH)-redox metabolism in HepG2 cells play a critical role in ASA-induced cytotoxicity. Using selected doses and time point for ASA toxicity, we have demonstrated that when GSH synthesis is inhibited in HepG2 cells by buthionine sulfoximine (BSO), prior to ASA tre...

  20. D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol alters cellular cholesterol homeostasis by modulating the endosome lipid domains.

    Science.gov (United States)

    Makino, Asami; Ishii, Kumiko; Murate, Motohide; Hayakawa, Tomohiro; Suzuki, Yusuke; Suzuki, Minoru; Ito, Kazuki; Fujisawa, Tetsuro; Matsuo, Hirotami; Ishitsuka, Reiko; Kobayashi, Toshihide

    2006-04-11

    D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP) is a frequently used inhibitor of glycosphingolipid biosynthesis. However, some interesting characteristics of D-PDMP cannot be explained by the inhibition of glycolipid synthesis alone. In the present study, we showed that d-PDMP inhibits the activation of lysosomal acid lipase by late endosome/lysosome specific lipid, bis(monoacylglycero)phosphate (also called as lysobisphosphatidic acid), through alteration of membrane structure of the lipid. When added to cultured fibroblasts, D-PDMP inhibits the degradation of low-density lipoprotein (LDL) and thus accumulates both cholesterol ester and free cholesterol in late endosomes/lysosomes. This accumulation results in the inhibition of LDL-derived cholesterol esterification and the decrease of cell surface cholesterol. We showed that D-PDMP alters cellular cholesterol homeostasis in a glycosphingolipid-independent manner using L-PDMP, a stereoisomer of D-PDMP, which does not inhibit glycosphingolipid synthesis, and mutant melanoma cell which is defective in glycolipid synthesis. Altering cholesterol homeostasis by D-PDMP explains the unique characteristics of sensitizing multidrug resistant cells by this drug. PMID:16584188

  1. Proteomic alterations in root tips of Arabidopsis thaliana seedlings under altered gravity conditions

    Science.gov (United States)

    Zheng, H. Q.; Wang, H.

    Gravity has a profound influence on plant growth and development Removed the influence of gravitational acceleration by spaceflight caused a wide range of cellular changes in plant Whole seedling that germinated and grown on clinostats showed the absent of gravitropism At the cellular level clinostat treatment has specific effects on plant cells such as induce alterations in cell wall composition increase production of heat-soluble proteins impact on the cellular energy metabolism facilitate a uniform distribution of plastids amyloplasts and increase number and volume of nucleoli A number of recent studies have shown that the exposure of Arabidopsis seedlings and callus cells to gravity stimulation hyper g-forces or clinostat rotation induces alterations in gene expression In our previous study the proteome of the Arabidopsis thaliana callus cells were separated by high resolution two-dimensional electrophoresis 2-DE Image analysis revealed that 80 protein spots showed quantitative and qualitative variations after exposure to clinostat rotation treatment We report here a systematic proteomic approach to investigate the altered gravity responsive proteins in root tip of Arabidopsis thaliana cv Landsberg erecta Three-day-old seedlings were exposed for 12h to a horizontal clinostat rotation H simulated weightlessness altered g-forces by centrifugation 7g hypergravity a vertical clinostat rotation V clinostat control or a stationary control grown conditions Total proteins of roots were extracted

  2. In vivo effects of dexamethasone and indomethacin on neutrophil-induced alterations of nasal epithelial mucosubstances

    International Nuclear Information System (INIS)

    Previous studies have shown that neutrophils migrating through rat nasal mucosal epithelium, in response to intranasal instillation of endotoxin, induce a transient decrease in stored epithelial mucosubstances. Prostaglandins and leukotrienes can either increase or decrease mucous secretion of airway epithelia in vitro. In this study, rats were treated with indomethacin a specific inhibitor of prostaglandin synthesis, or with dexamethasone, a general inhibitor of arachidonic acid metabolism, and challenged with intranasally instilled endotoxin. Dexamethasone alone or in combination with indomethacin, but not indomethacin alone, significantly altered the neutrophil response to intranasally instilled endotoxin and may have inhibited the neutrophil-induced decrease in stored mucosubstances. These data suggest that leukotrienes and possibly prostaglandins play a significant role in the coordinated response of the nasal mucosal epitholium to an acute inflammatory stimulus. (author)

  3. Neutrophils alter the inflammatory milieu by signal-dependent translation of constitutive messenger RNAs

    Science.gov (United States)

    Lindemann, Stephan W.; Yost, Christian C.; Denis, Melvin M.; McIntyre, Thomas M.; Weyrich, Andrew S.; Zimmerman, Guy A.

    2004-05-01

    The mechanisms by which neutrophils, key effector cells of the innate immune system, express new gene products in inflammation are largely uncharacterized. We found that they rapidly translate constitutive mRNAs when activated, a previously unrecognized response. One of the proteins synthesized without a requirement for transcription is the soluble IL-6 receptor , which translocates to endothelial cells and induces a temporal switch to mononuclear leukocyte recruitment. Its synthesis is regulated by a specialized translational control pathway that is inhibited by rapamycin, a bacterial macrolide with therapeutic efficacy in transplantation, inflammatory syndromes, and neoplasia. Signal-dependent translation in activated neutrophils may be a critical mechanism for alteration of the inflammatory milieu and a therapeutic target.

  4. Regional alterations of brain biogenic amines in young rats following chronic lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Dubas, T.C.; Stevenson, A.; Singhal, R.L.; Hrdina, P.D.

    1978-02-01

    An examination was made of neurochemical changes that occur in discrete brain regions of rats that have been chronically exposed to low levels of lead from birth, in order to provide further information on the involvement of brain biogenic amines in lead-induced neurotoxicity. Results indicate a relationship between exposure to lead and alterations in the brain levels of various putative neurotransmitters. However, changes in the functional activity of the neurotransmitter may not be adequately reflected in the change of its steady-state levels or may occur even in the absence of any changes in the actual concentrations. Lead may influence central neurotransmitter function by affecting one or several of the processes involved in the synthesis, release and/or disposition of biogenic amines.

  5. Total Synthesis of Propolisbenzofuran B†

    OpenAIRE

    Jones, Brian T.; Avetta, Christopher T.; Thomson, Regan J.

    2014-01-01

    The first total synthesis of propolisbenzofuran B, a bioactive natural product isolated from honeybee propolis resin, is reported. The convergent synthesis makes use of a silicon-tether controlled oxidative ketone–ketone cross-coupling and a novel benzofuran-generating cascade reaction to deliver the core structure of the natural product from readily prepared precursors.

  6. Organic synthesis with stable isotopes

    International Nuclear Information System (INIS)

    Described is a scheme for the synthesis of L-arginine-1-13C utilizing methods developed for the synthesis of L-ornithine-1-13C from L-ornithine-2-13C and then converting ornithine into arginine with the enzyme acylase

  7. Chemical synthesis on SU-8

    DEFF Research Database (Denmark)

    Qvortrup, Katrine; Taveras, Kennedy; Thastrup, Ole;

    2011-01-01

    In this paper we describe a highly effective surface modification of SU-8 microparticles, the attachment of appropriate linkers for solid-supported synthesis, and the successful chemical modification of these particles via controlled multi-step organic synthesis leading to molecules attached in an...

  8. Lactobacillusassisted synthesis of titanium nanoparticles

    Directory of Open Access Journals (Sweden)

    Jha Anal

    2007-01-01

    Full Text Available AbstractAn eco-friendlylactobacillussp. (microbe assisted synthesis of titanium nanoparticles is reported. The synthesis is performed at room temperature. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of Ti nanoparticles. Individual nanoparticles as well as a number of aggregates almost spherical in shape having a size of 40–60 nm are found.

  9. SYNTHESIS OF MYCOPHENOLIC ACID (MPA)

    DEFF Research Database (Denmark)

    2008-01-01

    The present invention relates to novel tools for improving MPA production. In particular, the present invention relates tofungal enzymes that are specific for MPA synthesis.......The present invention relates to novel tools for improving MPA production. In particular, the present invention relates tofungal enzymes that are specific for MPA synthesis....

  10. Scenario/Class Diagram Synthesis

    OpenAIRE

    Prabhune, Aniket; Mahajan, Reenal; Singhal, Mudita

    2003-01-01

    The scenario-synthesis problem in requirements analysis is explored in this report.The approach suggested by Khriss et al.is adapted for the domain of Digital Libraries. The results of the synthesis along with the entire transformation process are elaborated in this report.

  11. Memory-based logic synthesis

    CERN Document Server

    Sasao, Tsutomu

    2011-01-01

    This book describes the synthesis of logic functions using memories. It is useful to design field programmable gate arrays (FPGAs) that contain both small-scale memories, called look-up tables (LUTs), and medium-scale memories, called embedded memories. This is a valuable reference for both FPGA system designers and CAD tool developers, concerned with logic synthesis for FPGAs.

  12. An Alterities Required for Living Together

    Directory of Open Access Journals (Sweden)

    Wellington Amancio Da Silva

    2015-05-01

    Full Text Available This article outlines some existential concepts and socio-affective self, of others and nature on the altered perspective of Hannah Arendt (2010a, 2010b, 1997 and Leonardo Boff (1991, 1999, 2000 in their usual representations in everyday life. From the point of view of the analysis of the Cartesian world view, the self that is considering in the foreground in the face of the other and the world, representations and set up all show that there is always from the perspective of the self, the ego cogitans, egocentrism. This article urges readers to invite everyone to rethink this rather artificial logic governing human relations from Western, especially the Middle Ages, and it has shown injustices from that imbalance of meanings and judgments in the face of otherness, which bring in ourselves.

  13. Immune system alterations in amyotrophic lateral sclerosis

    DEFF Research Database (Denmark)

    Hovden, H; Frederiksen, J L; Pedersen, S W

    2013-01-01

    Amyotrophic lateral sclerosis is a disease of which the underlying cause and pathogenesis are unknown. Cumulatative data clearly indicates an active participation by the immune system in the disease. An increasingly recognized theory suggests a non-cell autonomous mechanism, meaning that multiple...... cells working together are necessary for the pathogenesis of the disease. Observed immune system alterations could indicate an active participation in this mechanism. Damaged motor neurons are able to activate microglia, astrocytes and the complement system, which further can influence each other and...... contribute to neurodegeneration. Infiltrating peripheral immune cells appears to correlate with disease progression, but their significance and composition is unclear. The deleterious effects of this collaborating system of cells appear to outweigh the protective aspects, and revealing this interplay might...

  14. Hydraulic characterization of hydrothermally altered Nopal tuff

    International Nuclear Information System (INIS)

    Understanding the mechanics of variably saturated flow in fractured-porous media is of fundamental importance to evaluating the isolation performance of the proposed high-level radioactive waste repository for the Yucca Mountain site. Developing that understanding must be founded on the analysis and interpretation of laboratory and field data. This report presents an analysis of the unsaturated hydraulic properties of tuff cores from the Pena Blanca natural analog site in Mexico. The basic intent of the analysis was to examine possible trends and relationships between the hydraulic properties and the degree of hydrothermal alteration exhibited by the tuff samples. These data were used in flow simulations to evaluate the significance of a particular conceptual (composite) model and of distinct hydraulic properties on the rate and nature of water flow

  15. Functional alterations in macrophages after hypoxia selection.

    Science.gov (United States)

    Degrossoli, Adriana; Giorgio, Selma

    2007-01-01

    Regions of low oxygen tension are common features of inflamed and infected tissues and provide physiologic selective pressure for the expansion of cells with enhanced hypoxia tolerance. The aim of this study was to investigate whether macrophages resistant to death induced by hypoxia were accompanied by functional alterations. A mouse macrophage cell line (J774 cells) was used to obtain subpopulations of death-resistant macrophages induced by long-term exposure to severe hypoxia (J774 macrophages to periods of severe hypoxia results in the selection of cells with phenotypes associated with the modulation of heat-shock protein 70 kDa (HSP70) expression, tumor necrosis factor-alpha (TNF-alpha), and nitric oxide (NO) production and reduced susceptibility to parasite Leishmania infection. Thus, we suggest that hypoxia-selected macrophages may influence the outcome of inflammation and infection. PMID:17202589

  16. [Molecular alterations in melanoma and targeted therapies].

    Science.gov (United States)

    Mourah, Samia; Lebbé, Céleste

    2014-12-01

    Melanoma is a skin cancer whose incidence is increasing steadily. The recent discovery of frequent and recurrent genetic alterations in cutaneous melanoma allowed a molecular classification of tumors into distinct subgroups, and paved the way for targeted therapy. Several signaling pathways are involved in the progression of this disease with oncogenic mutations affecting signaling pathways: MAPK, PI3K, cAMP and cyclin D1/CDK4. In each of these pathways, several potential therapeutic targets have been identified and specific inhibitors have already been developed and have shown clinical efficacy. The use of these inhibitors is often conditioned by tumors genotyping. In France, melanomas genotyping is supported by the platforms of the National Cancer Institute (INCA), which implemented a national program ensuring access to innovation for personalized medicine. The identification of new targets in melanoma supplies a very active dynamic development of innovative molecules contributing to changing the therapeutic landscape of this pathology. PMID:25776766

  17. Epigenetic alterations associated with cholangiocarcinoma (review).

    Science.gov (United States)

    Isomoto, Hajime

    2009-08-01

    Cholangiocarcinoma (CCA) is a highly lethal malignant tumor arising from the biliary tract epithelium. Chronic inflammatory conditions, including primary sclerosing cholangitis, liver fluke infestation, and hepatolithiasis, are considered risk factors, but the cause is still unknown in most cases. Recent advances in molecular pathogenesis have highlighted the importance of epigenetic alterations, including promoter hypermethylation and histone deacetylation, in the process of cholangiocarcinogenesis. More recently, research interest has been focusing on microRNA (mir), a major subtype of non-coding RNA. Mir is highly conserved among species and regulates the expression of specific target genes by binding to the 3'-untranslated regions of messenger RNA. The number of studies on a possible link between mir and various cancers is growing. This review provides a comprehensive overview of the genes currently known to be hypermethylated in CCA and their putative roles in cholangiocarcinogenesis. The epigenetic role of mir in the pathogenesis of CCA is also discussed. PMID:19578760

  18. Saccadic Alterations in Severe Developmental Dyslexia

    Directory of Open Access Journals (Sweden)

    Stefano Pensiero

    2013-01-01

    Full Text Available It is not sure if persons with dyslexia have ocular motor deficits in addition to their deficits in rapid visual information processing. A 15-year-old boy afflicted by severe dyslexia was submitted to saccadic eye movement recording. Neurological and ophthalmic examinations were normal apart from the presence of an esophoria for near and slightly longer latencies of pattern visual evoked potentials. Subclinical saccadic alterations were present, which could be at the basis of the reading pathology: (1 low velocities (and larger durations of the adducting saccades of the left eye with undershooting and long-lasting postsaccadic onward drift, typical of the internuclear ophthalmoplegia; (2 saccades interrupted in mid-flight and fixation instability, which are present in cases of brainstem premotor disturbances.

  19. Molecular Alterations Associated with Osteosarcoma Development

    Directory of Open Access Journals (Sweden)

    Kosei Ando

    2012-01-01

    Full Text Available Osteosarcoma is the most frequent malignant primary bone tumor characterized by a high potency to form lung metastases which is the main cause of death. Unfortunately, the conventional chemotherapy is not fully effective on osteosarcoma metastases. The progression of a primary tumor to metastasis requires multiple processes, which are neovascularization, proliferation, invasion, survival in the bloodstream, apoptosis resistance, arrest at a distant organ, and outgrowth in secondary sites. Consequently, recent studies have revealed new insights into the molecular mechanisms of metastasis development. The understanding of the mechanism of molecular alterations can provide the identification of novel therapeutic targets and/or prognostic markers for osteosarcoma treatment to improve the clinical outcome.

  20. PCR-based gene synthesis to produce recombinant proteins for crystallization

    Directory of Open Access Journals (Sweden)

    Byrne-Steele Miranda L

    2008-04-01

    Full Text Available Abstract Background Gene synthesis technologies are an important tool for structural biology projects, allowing increased protein expression through codon optimization and facilitating sequence alterations. Existing methods, however, can be complex and not always reproducible, prompting researchers to use commercial suppliers rather than synthesize genes themselves. Results A PCR-based gene synthesis method, referred to as SeqTBIO, is described to efficiently assemble the coding regions of two novel hyperthermophilic proteins, PAZ (Piwi/Argonaute/Zwille domain, a siRNA-binding domain of an Argonaute protein homologue and a deletion mutant of a family A DNA polymerase (PolA. The gene synthesis procedure is based on sequential assembly such that homogeneous DNA products can be obtained after each synthesis step without extensive manipulation or purification requirements. Coupling the gene synthesis procedure to in vivo homologous recombination techniques allows efficient subcloning and site-directed mutagenesis for error correction. The recombinant proteins of PAZ and PolA were subsequently overexpressed in E. coli and used for protein crystallization. Crystals of both proteins were obtained and they were suitable for X-ray analysis. Conclusion We demonstrate, by using PAZ and PolA as examples, the feasibility of integrating the gene synthesis, error correction and subcloning techniques into a non-automated gene to crystal pipeline such that genes can be designed, synthesized and implemented for recombinant expression and protein crystallization.

  1. Leptin Modulates Norepinephrine-Mediated Melatonin Synthesis in Cultured Rat Pineal Gland

    Directory of Open Access Journals (Sweden)

    Rodrigo Antonio Peliciari-Garcia

    2013-01-01

    Full Text Available Pineal melatonin synthesis can be modulated by many peptides, including insulin. Because melatonin appears to alter leptin synthesis, in this work we aimed to investigate whether leptin would have a role on norepinephrine- (NE-mediated melatonin synthesis in cultured rat pineal glands. According to our data, cultured rat pineal glands express leptin receptor isoform b (Ob-Rb. Pineal expression of Ob-Rb mRNA was also observed in vivo. Administration of leptin (1 nM associated with NE (1 µM reduced melatonin content as well as arylalkylamine-N-acetyl transferase (AANAT activity and expression in cultured pineal glands. Leptin treatment per se induced the expression of STAT3 in cultured pineal glands, but STAT3 does not participate in the leptin modulation of NE-mediated pineal melatonin synthesis. In addition, the expression of inducible cAMP early repressor (ICER was further induced by leptin challenge when associated with NE. In conclusion, leptin inhibition of pineal melatonin synthesis appears to be mediated by a reduction in AANAT activity and expression as well as by increased expression of Icer mRNA. Peptidergic signaling within the pineal gland appears to be one of the most important signals which modulates melatonin synthesis; leptin, as a member of this system, is not an exception.

  2. Quantitative single cell monitoring of protein synthesis at subcellular resolution using fluorescently labeled tRNA.

    Science.gov (United States)

    Barhoom, Sima; Kaur, Jaskiran; Cooperman, Barry S; Smorodinsky, Nechama I; Smilansky, Zeev; Ehrlich, Marcelo; Elroy-Stein, Orna

    2011-10-01

    We have developed a novel technique of using fluorescent tRNA for translation monitoring (FtTM). FtTM enables the identification and monitoring of active protein synthesis sites within live cells at submicron resolution through quantitative microscopy of transfected bulk uncharged tRNA, fluorescently labeled in the D-loop (fl-tRNA). The localization of fl-tRNA to active translation sites was confirmed through its co-localization with cellular factors and its dynamic alterations upon inhibition of protein synthesis. Moreover, fluorescence resonance energy transfer (FRET) signals, generated when fl-tRNAs, separately labeled as a FRET pair occupy adjacent sites on the ribosome, quantitatively reflect levels of protein synthesis in defined cellular regions. In addition, FRET signals enable detection of intra-populational variability in protein synthesis activity. We demonstrate that FtTM allows quantitative comparison of protein synthesis between different cell types, monitoring effects of antibiotics and stress agents, and characterization of changes in spatial compartmentalization of protein synthesis upon viral infection. PMID:21795382

  3. Riparian invasive alters stream nitrogen dynamics.

    Science.gov (United States)

    Mineau, M.; Baxter, C.; Marcarelli, A.; Minshall, G.

    2008-12-01

    Invasive species may be most likely to have strong effects on the ecosystem they invade when they contribute a new function such as nitrogen (N) fixation. Russian olive (Eleagnus angustifolia) is a non-native invasive tree which is rapidly spreading along riparian corridors in the American West. Russian olive is a nitrogen fixing plant due to a symbiotic relationship with Actinomycetes and is invading systems that frequently lack a strong native N fixer. The contribution of reactive N by these invasive riparian plants to soils may also be altering N cycling and processing in the adjacent streams. We measured nutrient limitation via periphyton growth on nutrient diffusing substrates and nitrate uptake using short term nitrate additions in Deep Creek, ID. Measurements were made in three reaches along a Russian olive invasion gradient, with an upstream reference reach that has no Russian olive and two downstream invaded reaches, one with moderate density and one with high density. Periphyton growth in Deep Creek was significantly N limited in the reference reach while the moderately invaded reach showed no significant limitation and the highly invaded reach was significantly P limited. The nitrate uptake velocity (Vf) for both of the invaded reaches was an order of magnitude less than the reference reach, implying that biological demand for nitrate is significantly less in the invaded reaches than the reference. Considering the current extent of Russian olive invasion and its continued rapid spread, possible alteration of N cycling in waterways may have important implications for the management of both this invasive species and management of nutrient pollution in waters of the western U.S.

  4. Glaucoma alters the circadian timing system.

    Science.gov (United States)

    Drouyer, Elise; Dkhissi-Benyahya, Ouria; Chiquet, Christophe; WoldeMussie, Elizabeth; Ruiz, Guadalupe; Wheeler, Larry A; Denis, Philippe; Cooper, Howard M

    2008-01-01

    Glaucoma is a widespread ocular disease and major cause of blindness characterized by progressive, irreversible damage of the optic nerve. Although the degenerative loss of retinal ganglion cells (RGC) and visual deficits associated with glaucoma have been extensively studied, we hypothesize that glaucoma will also lead to alteration of the circadian timing system. Circadian and non-visual responses to light are mediated by a specialized subset of melanopsin expressing RGCs that provide photic input to mammalian endogenous clock in the suprachiasmatic nucleus (SCN). In order to explore the molecular, anatomical and functional consequences of glaucoma we used a rodent model of chronic ocular hypertension, a primary causal factor of the pathology. Quantitative analysis of retinal projections using sensitive anterograde tracing demonstrates a significant reduction (approximately 50-70%) of RGC axon terminals in all visual and non-visual structures and notably in the SCN. The capacity of glaucomatous rats to entrain to light was challenged by exposure to successive shifts of the light dark (LD) cycle associated with step-wise decreases in light intensity. Although glaucomatous rats are able to entrain their locomotor activity to the LD cycle at all light levels, they require more time to re-adjust to a shifted LD cycle and show significantly greater variability in activity onsets in comparison with normal rats. Quantitative PCR reveals the novel finding that melanopsin as well as rod and cone opsin mRNAs are significantly reduced in glaucomatous retinas. Our findings demonstrate that glaucoma impacts on all these aspects of the circadian timing system. In light of these results, the classical view of glaucoma as pathology unique to the visual system should be extended to include anatomical and functional alterations of the circadian timing system. PMID:19079596

  5. Glaucoma Alters the Circadian Timing System

    Science.gov (United States)

    Drouyer, Elise; Dkhissi-Benyahya, Ouria; Chiquet, Christophe; WoldeMussie, Elizabeth; Ruiz, Guadalupe; Wheeler, Larry A.; Denis, Philippe; Cooper, Howard M.

    2008-01-01

    Glaucoma is a widespread ocular disease and major cause of blindness characterized by progressive, irreversible damage of the optic nerve. Although the degenerative loss of retinal ganglion cells (RGC) and visual deficits associated with glaucoma have been extensively studied, we hypothesize that glaucoma will also lead to alteration of the circadian timing system. Circadian and non-visual responses to light are mediated by a specialized subset of melanopsin expressing RGCs that provide photic input to mammalian endogenous clock in the suprachiasmatic nucleus (SCN). In order to explore the molecular, anatomical and functional consequences of glaucoma we used a rodent model of chronic ocular hypertension, a primary causal factor of the pathology. Quantitative analysis of retinal projections using sensitive anterograde tracing demonstrates a significant reduction (∼50–70%) of RGC axon terminals in all visual and non-visual structures and notably in the SCN. The capacity of glaucomatous rats to entrain to light was challenged by exposure to successive shifts of the light dark (LD) cycle associated with step-wise decreases in light intensity. Although glaucomatous rats are able to entrain their locomotor activity to the LD cycle at all light levels, they require more time to re-adjust to a shifted LD cycle and show significantly greater variability in activity onsets in comparison with normal rats. Quantitative PCR reveals the novel finding that melanopsin as well as rod and cone opsin mRNAs are significantly reduced in glaucomatous retinas. Our findings demonstrate that glaucoma impacts on all these aspects of the circadian timing system. In light of these results, the classical view of glaucoma as pathology unique to the visual system should be extended to include anatomical and functional alterations of the circadian timing system. PMID:19079596

  6. Wound trauma alters ionizing radiation dose assessment

    Directory of Open Access Journals (Sweden)

    Kiang Juliann G

    2012-06-01

    Full Text Available Abstract Background Wounding following whole-body γ-irradiation (radiation combined injury, RCI increases mortality. Wounding-induced increases in radiation mortality are triggered by sustained activation of inducible nitric oxide synthase pathways, persistent alteration of cytokine homeostasis, and increased susceptibility to bacterial infection. Among these factors, cytokines along with other biomarkers have been adopted for biodosimetric evaluation and assessment of radiation dose and injury. Therefore, wounding could complicate biodosimetric assessments. Results In this report, such confounding effects were addressed. Mice were given 60Co γ-photon radiation followed by skin wounding. Wound trauma exacerbated radiation-induced mortality, body-weight loss, and wound healing. Analyses of DNA damage in bone-marrow cells and peripheral blood mononuclear cells (PBMCs, changes in hematology and cytokine profiles, and fundamental clinical signs were evaluated. Early biomarkers (1 d after RCI vs. irradiation alone included significant decreases in survivin expression in bone marrow cells, enhanced increases in γ-H2AX formation in Lin+ bone marrow cells, enhanced increases in IL-1β, IL-6, IL-8, and G-CSF concentrations in blood, and concomitant decreases in γ-H2AX formation in PBMCs and decreases in numbers of splenocytes, lymphocytes, and neutrophils. Intermediate biomarkers (7 – 10 d after RCI included continuously decreased γ-H2AX formation in PBMC and enhanced increases in IL-1β, IL-6, IL-8, and G-CSF concentrations in blood. The clinical signs evaluated after RCI were increased water consumption, decreased body weight, and decreased wound healing rate and survival rate. Late clinical signs (30 d after RCI included poor survival and wound healing. Conclusion Results suggest that confounding factors such as wounding alters ionizing radiation dose assessment and agents inhibiting these responses may prove therapeutic for radiation combined

  7. Gamma-interferon alters globin gene expression in neonatal and adult erythroid cells

    Energy Technology Data Exchange (ETDEWEB)

    Miller, B.A.; Perrine, S.P.; Antognetti, G.; Perlmutter, D.H.; Emerson, S.G.; Sieff, C.; Faller, D.V.

    1987-06-01

    The effect of gamma-interferon on fetal hemoglobin synthesis by purified cord blood, fetal liver, and adult bone marrow erythroid progenitors was studied with a radioligand assay to measure hemoglobin production by BFU-E-derived erythroblasts. Coculture with recombinant gamma-interferon resulted in a significant and dose-dependent decrease in fetal hemoglobin production by neonatal and adult, but not fetal, BFU-E-derived erythroblasts. Accumulation of fetal hemoglobin by cord blood BFU-E-derived erythroblasts decreased up to 38.1% of control cultures (erythropoietin only). Synthesis of both G gamma/A gamma globin was decreased, since the G gamma/A gamma ratio was unchanged. Picograms fetal hemoglobin per cell was decreased by gamma-interferon addition, but picograms total hemoglobin was unchanged, demonstrating that a reciprocal increase in beta-globin production occurred in cultures treated with gamma-interferon. No toxic effect of gamma-interferon on colony growth was noted. The addition of gamma-interferon to cultures resulted in a decrease in the percentage of HbF produced by adult BFU-E-derived cells to 45.6% of control. Fetal hemoglobin production by cord blood, fetal liver, and adult bone marrow erythroid progenitors, was not significantly affected by the addition of recombinant GM-CSF, recombinant interleukin 1 (IL-1), recombinant IL-2, or recombinant alpha-interferon. Although fetal progenitor cells appear unable to alter their fetal hemoglobin program in response to any of the growth factors added here, the interaction of neonatal and adult erythroid progenitors with gamma-interferon results in an altered expression of globin genes.

  8. Synthesis in land change science

    DEFF Research Database (Denmark)

    Magliocca, Nicholas R.; Rudel, Thomas K.; Verburg, Peter H.;

    2015-01-01

    these changes, land change science (LCS) draws on a wide array synthetic and meta-study techniques to generate global and regional knowledge from local case studies of land change. Here, we review the characteristics and applications of synthesis methods in LCS and assess the current state of synthetic...... research based on a meta-analysis of synthesis studies from 1995 to 2012. Publication of synthesis research is accelerating, with a clear trend toward increasingly sophisticated and quantitative methods, including meta-analysis. Detailed trends in synthesis objectives, methods, and land change phenomena...... and world regions most commonly studied are presented. Significant challenges to successful synthesis research in LCS are also identified, including issues of interpretability and comparability across case-studies and the limits of and biases in the geographic coverage of case studies. Nevertheless...

  9. Radiochemical synthesis of etomoxir

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Hafiz G. [Institute of Nuclear Medicine and Oncology (INMOL), New Campus Road, Lahore (Pakistan); Yunus, M. [University of the Punjab, New Campus Road, Lahore (Pakistan); Feinendegen, Ludwig E., E-mail: feinendegen@gmx.ne [Department of Nuclear Medicine, Heinrich-Heine University Duesseldorf, Wannental 45, 88131 Lindau (Germany)

    2011-02-15

    Sodium 2-{l_brace}6-(4-chlorophenoxy)hexyl{r_brace}oxirane-2-carboxylate (Etomoxir) inhibits transport of fatty acids via the carnitine shuttle into mitochondria of muscle cells and prevents long chain fatty acids from providing energy through {beta}-oxidation especially for muscle contraction. The objective of this synthesis is to develop a method for radioiodination of Etomoxir in order to explore its potential in diagnostic metabolic studies and molecular imaging. Thus, a method is described for the radiochemical synthesis and purification of ethyl 2-{l_brace}6-(4-[{sup 131}I]iodophenoxy)hexyl{r_brace}oxirane-2-carboxylate (3) and 2-{l_brace}6-(4-[{sup 131}I]iodo-phenoxy)hexyl{r_brace}oxirane-2-carboxylic acid (4). For the synthesis of these new agents, ethyl 2-{l_brace}6-(4-bromophenoxy)hexyl{r_brace}oxirane-2-carboxylate (1) and 2-{l_brace}6-(4-bromophenoxy)hexyl{r_brace}oxirane-2-carboxylic acid (2) were refluxed with [{sup 131}I]NaI in the presence of anhydrous acetone at a temperature of 80 {sup o}C and 90 {sup o}C for a period of 3-4 hours, respectively. The method of radiolabeling, based on the nucleophilic exchange reaction, resulted in a radiochemical yield of 43% and 67% for compounds 3 and 4, respectively. This paper reports on the labeling of etomoxir with radioiodine as {sup 124}I labeled etomoxir may be of great importance in molecular imaging.

  10. Synthesis of graphene

    Science.gov (United States)

    Bhuyan, Md. Sajibul Alam; Uddin, Md. Nizam; Islam, Md. Maksudul; Bipasha, Ferdaushi Alam; Hossain, Sayed Shafayat

    2016-02-01

    Graphene, a two-dimensional material of sp2 hybridization carbon atoms, has fascinated much attention in recent years owing to its extraordinary electronic, optical, magnetic, thermal, and mechanical properties as well as large specific surface area. For the tremendous application of graphene in nano-electronics, it is essential to fabricate high-quality graphene in large production. There are different methods of generating graphene. This review summarizes the exfoliation of graphene by mechanical, chemical and thermal reduction and chemical vapor deposition and mentions their advantages and disadvantages. This article also indicates recent advances in controllable synthesis of graphene, illuminates the problems, and prospects the future development in this field.

  11. Synthesis of deuterated clenbuterol

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, Ole [Risoe National Lab., Roskilde (Denmark). Solid State Physics Dept.; Egsgaard, Helge; Larsen, Elfinn [Risoe National Lab., Roskilde (Denmark). Science and Technology Dept.

    1996-11-01

    The synthesis of D{sub 9}-clenbuterol (I) and D{sub 3}-clenbuterol (II) is described. D{sub 9}-clenbuterol (I) was prepared from 4-amino-{alpha}-bromo-3, 5-dichloroacetophenone by reaction with D{sub 9}-tert-butylamine followed by reduction of the keto group with NaBH{sub 4}. D{sub 3}-clenbuterol (II) was prepared from 4-amino-{alpha}-tert-butylamino-3, 5-dichloroacetophenone by an exchange reaction of the {alpha}-hydrogens with deuterium followed by reduction of the keto group with NaBD{sub 4}. The eventual products were characterized by mass spectrometry and NMR. (author).

  12. [New synthesis empathogenic agents].

    Science.gov (United States)

    Velea, D; Hautefeuille, M; Vazeille, G; Lantran-Davoux, C

    1999-01-01

    The use of synthesis drugs is the object of numerous written articles and TV programs in the last, decade. These synthesis drugs or "designer drugs", are well known for their ability to enhance, reinforce or appease social difficulties and relationships. In the research for empathetic and entactogenic relations one discover an obvious lack of communication and "warmth" in personal or professional relationship. An image of chemical "well being" has become a frequent stereotype of a society with an atrophying of performance and values while supposedly dedicating itself to individual performance. The youths are the first victims of these new drugs, the economical and social environment are the main reinforcing factors of this behaviour. The main characteristic of these drugs, is the non-recognition of their danger, some users go so far as to describe this category of substances as "drugs which are not drugs". As a characteristic, the use of a these synthesis drugs is almost recreative, during the week-end and holiday. The drug addiction is different than that of opiates or cocaine. One can observe some cases of real dependence--corresponding to the DSW IV criterion--when the personality of the users is the main characteristic (narcissic failure, immature personality, family and school problems). Many adverse effects--hypertension, kidney failure, psychoses--were declared. The mass-media has presented many articles concerning Ecstasy (MDMA). This is the most used drug during the rave parties. Its adverse effects are well known and proven. The authors would like to present other more recent synthesis drugs, also known as "analogs". These drugs, a kind of mixture between amphetamine-like (MDMA, MBDB, MDA) and misused medicines (ketamine, gamma OH, atropine) represent a real danger. GHB, 2 CB, HMB, are some of these recent substances. The possibility to procure them on the Web, or to produce them by oneself, add to their danger because of the lack of controls on toxicity

  13. Total Synthesis of (-)-Daphenylline.

    Science.gov (United States)

    Yamada, Ryosuke; Adachi, Yohei; Yokoshima, Satoshi; Fukuyama, Tohru

    2016-05-10

    Total synthesis of (-)-daphenylline, a hexacyclic Daphniphyllum alkaloid, was achieved. Construction of the tricyclic DEF ring system was initiated by asymmetric Negishi coupling followed by an intramolecular Friedel-Crafts reaction. Installation of a side chain onto the tricyclic core was carried out through Sonogashira coupling, stereocontrolled Claisen rearrangement by taking advantage of the characteristic conformation of the tricyclic DEF core, and the stereoselective alkylation of a lactone. After the introduction of a glycine unit, the ABC ring system was stereoselectively constructed through intramolecular cycloaddition of the cyclic azomethine ylide. PMID:27062676

  14. Plasma synthesis of nanopowders

    Energy Technology Data Exchange (ETDEWEB)

    Vollath, Dieter, E-mail: dieter.vollath@nanoconsulting.d [NanoConsulting (Germany)

    2008-12-15

    There is a huge variety of plasma processes for synthesis of nanoparticulate powders. They may be grouped with respect to operating temperature, which is the essential parameter with respect to the properties of the products. In view of industrial production, the highest degree of maturity is found in high temperature processes working under ambient pressure. For products, where well-defined properties are demanded, low temperature microwave plasma processes are best suited. Additionally, these processes allow coating of the produced particles, even with organic phases. Other processes where plasmas are involved, such as laser or flame processes coupled with electric fields have, to some extent, a high potential for development.

  15. Synthesis of deuterated clenbuterol

    International Nuclear Information System (INIS)

    The synthesis of D9-clenbuterol (I) and D3-clenbuterol (II) is described. D9-clenbuterol (I) was prepared from 4-amino-α-bromo-3, 5-dichloroacetophenone by reaction with D9-tert-butylamine followed by reduction of the keto group with NaBH4. D3-clenbuterol (II) was prepared from 4-amino-α-tert-butylamino-3, 5-dichloroacetophenone by an exchange reaction of the α-hydrogens with deuterium followed by reduction of the keto group with NaBD4. The eventual products were characterized by mass spectrometry and NMR. (author)

  16. Microemulsion Synthesis of Nanoparticles

    Directory of Open Access Journals (Sweden)

    Gotić, M.

    2013-11-01

    Full Text Available Nanoparticles and nanomaterials have wide applications in electronics, physics, material design, being also utilized as sensors, catalysts, and more and more in biomedicine. Microemulsions are an exceptionally suitable medium for the synthesis of nanoparticles due to their thermodynamical stability, great solubility of both polar and nonpolar components, as well as their ability to control the size, dispersity and shape of the particles. This review presents microemulsion techniques for the synthesis of inorganic nanoparticles. It takes place in water-in-oil microemulsions by mixing one microemulsion with a cationic precursor, and the other with a precipitating or reducing agent, or by direct addition of reducing agents or gas (O2, NH3 ili CO2 into microemul sion (Fig. 1. Metal nanoparticles are used as catalysts, sensors, ferrofluids etc. They are produced by reducing the metal cation with a suitable reducing agent. In a similar way, one can prepare nanoparticles of alloys from the metal salts, provided that the metals are mutually soluble. The microemulsion technique is also suitable for depositing nanoparticles onto various surfaces. Highly active catalysts made from nanoparticles of Pt, Pd, Rh and other noble metals may be obtained in this way. Metal oxides and hydroxides may be prepared by hydrolysis or precipitation in the water core of microemulsion. Precipitation can be initiated by adding the base or precipitating agent into the microemulsion with water solution of metal ions. Similarly, nanoparticles may be prepared of sulphides, halogenides, cyanides, carbonates, sulphates and other insoluble metal salts. To prevent oxidation of nanoparticles, especially Fe, the particles are coated with inert metals, oxides, various polymers etc. Coating may provide additional functionality; e.g. coating with gold allows subsequent functionalization with organic compounds containing sulphur, due to the strong Au–S bond. Polymer coatings decrease

  17. Synthesis of expressed viewpoints

    International Nuclear Information System (INIS)

    A variety of viewpoints were voiced at the workshop either in oral presentations or in the ensuing discussions. These viewpoints have been collected and organized in six broad areas presented and discussed in this synthesis: necessary diversity of regulatory processes and regulation, assuring long-term radiological protection, tools to demonstrate repository performance, ethical concerns burdens versus responsibility and duties versus capacity, making the long-term disposal objectives clear and transparent, foreseeing and explaining the decision-making process. (A.L.B.)

  18. Glucose metabolism during fasting is altered in experimental porphobilinogen deaminase deficiency.

    Science.gov (United States)

    Collantes, María; Serrano-Mendioroz, Irantzu; Benito, Marina; Molinet-Dronda, Francisco; Delgado, Mercedes; Vinaixa, María; Sampedro, Ana; Enríquez de Salamanca, Rafael; Prieto, Elena; Pozo, Miguel A; Peñuelas, Iván; Corrales, Fernando J; Barajas, Miguel; Fontanellas, Antonio

    2016-04-01

    Porphobilinogen deaminase (PBGD) haploinsufficiency (acute intermittent porphyria, AIP) is characterized by neurovisceral attacks when hepatic heme synthesis is activated by endogenous or environmental factors including fasting. While the molecular mechanisms underlying the nutritional regulation of hepatic heme synthesis have been described, glucose homeostasis during fasting is poorly understood in porphyria. Our study aimed to analyse glucose homeostasis and hepatic carbohydrate metabolism during fasting in PBGD-deficient mice. To determine the contribution of hepatic PBGD deficiency to carbohydrate metabolism, AIP mice injected with a PBGD-liver gene delivery vector were included. After a 14 h fasting period, serum and liver metabolomics analyses showed that wild-type mice stimulated hepatic glycogen degradation to maintain glucose homeostasis while AIP livers activated gluconeogenesis and ketogenesis due to their inability to use stored glycogen. The serum of fasted AIP mice showed increased concentrations of insulin and reduced glucagon levels. Specific over-expression of the PBGD protein in the liver tended to normalize circulating insulin and glucagon levels, stimulated hepatic glycogen catabolism and blocked ketone body production. Reduced glucose uptake was observed in the primary somatosensorial brain cortex of fasted AIP mice, which could be reversed by PBGD-liver gene delivery. In conclusion, AIP mice showed a different response to fasting as measured by altered carbohydrate metabolism in the liver and modified glucose consumption in the brain cortex. Glucose homeostasis in fasted AIP mice was efficiently normalized after restoration of PBGD gene expression in the liver. PMID:26908609

  19. Tenascin-x deficiency mimics ehlers-danlos syndrome in mice through alteration of collagen deposition

    Energy Technology Data Exchange (ETDEWEB)

    Mao, J.R.; Taylor, G.; Dean, W.B.; Wagner, D.R.; Afzal, V.; Lotz, J.C.; Rubin, E.M.; Bristow, J.

    2002-03-01

    Tenascin-X is a large extracellular matrix protein of unknown function1-3. Tenascin-X deficiency in humans is associated with Ehlers-Danlos syndrome4,5, a generalized connective tissue disorder resulting from altered metabolism of the fibrillar collagens6. Because TNXB is the first Ehlers-Danlos syndrome gene that does not encode a fibrillar collagen or collagen-modifying enzyme7-14, we suggested that tenascin-X might regulate collagen synthesis or deposition15. To test this hypothesis, we inactivated Tnxb in mice. Tnxb-/- mice showed progressive skin hyperextensibility, similar to individuals with Ehlers-Danlos syndrome. Biomechanical testing confirmed increased deformability and reduced tensile strength of their skin. The skin of Tnxb-/- mice was histologically normal, but its collagen content was significantly reduced. At the ultrastructural level, collagen fibrils of Tnxb-/- mice were of normal size and shape, but the density of fibrils in their skin was reduced, commensurate with the reduction in collagen content. Studies of cultured dermal fibroblasts showed that although synthesis of collagen I by Tnxb-/- and wildtype cells was similar, Tnxb-/- fibroblasts failed to deposit collagen I into cell-associated matrix. This study confirms a causative role for TNXB in human Ehlers-Danlos syndrome and suggests that tenascin-X is an essential regulator of collagen deposition by dermal fibroblasts.

  20. Expression of human dopamine receptor in potato (Solanum tuberosum results in altered tuber carbon metabolism

    Directory of Open Access Journals (Sweden)

    Świędrych Anna

    2005-02-01

    Full Text Available Abstract Background Even though the catecholamines (dopamine, norepinephrine and epinephrine have been detected in plants their role is poorly documented. Correlations between norepinephrine, soluble sugars and starch concentration have been recently reported for potato plants over-expressing tyrosine decarboxylase, the enzyme mediating the first step of catecholamine synthesis. More recently norepinephrine level was shown to significantly increase after osmotic stress, abscisic acid treatment and wounding. Therefore, it is possible that catecholamines might play a role in plant stress responses by modulating primary carbon metabolism, possibly by a mechanism similar to that in animal cells. Since to date no catecholamine receptor has been identified in plants we transformed potato plants with a cDNA encoding human dopamine receptor (HD1. Results Tuber analysis of transgenic plants revealed changes in the activities of key enzymes mediating sucrose to starch conversion (ADP-glucose phosphorylase and sucrose synthase and sucrose synthesis (sucrose phosphate synthase leading to altered content of both soluble sugars and starch. Surprisingly the catecholamine level measured in transgenic plants was significantly increased; the reason for this is as yet unknown. However the presence of the receptor affected a broader range of enzyme activities than those affected by the massive accumulation of norepinephrine reported for plants over-expressing tyrosine decarboxylase. Therefore, it is suggested that the presence of the exogenous receptor activates catecholamine cAMP signalling in plants. Conclusions Our data support the possible involvement of catecholamines in regulating plant carbon metabolism via cAMP signalling pathway.

  1. Effects of secondary alteration on the composition of free and IOM-derived monocarboxylic acids in carbonaceous chondrites

    Science.gov (United States)

    Aponte, José C.; Alexandre, Marcelo R.; Wang, Yi; Brearley, Adrian J.; Alexander, Conel M. O.'D.; Huang, Yongsong

    2011-05-01

    Monocarboxylic acids (MCAs) are important astrobiologically because they are often the most abundant soluble compounds in carbonaceous chondrites (CCs) and are potential synthetic end products for many biologically important compounds. However, there has been no systematic study on the effect of parent body alteration on molecular and isotopic variability of MCAs. Since MCAs in meteorites are dominated by low molecular weight (C1-C8), highly volatile compounds, their distributions are likely to be particularly sensitive to secondary alteration processes. In contrast, the aliphatic side chains of insoluble organic matter (IOM) in CCs, whose composition has been shown to be closely related to the MCAs, may be far more resistant to secondary alteration. In the present study, we determined the distributions and isotopic ratios of free and IOM-derived MCAs in six carbonaceous chondrites with a range of classifications: Murchison (CM2), EET 87770 (CR2), ALH 83034 (CM1), ALH 83033 (CM2), MET 00430 (CV3) and WIS 91600 (C2). We compare mineralogical and petrological characteristics to the MCAs distributions to better define the processes leading to the synthesis and alteration of meteoritic MCAs. Our results show that aqueous and especially thermal alteration in the parent bodies led to major loss of free MCAs and depletion of straight relative to branched chain compounds. However, the MCAs derived from aliphatic side chains of IOM are well preserved despite of secondary alterations. The molecular and isotopic similarities of IOM-derived MCAs in different chondrite samples indicate very similar synthetic histories for organic matter in different meteorites.

  2. Altered potassium homeostasis in Crohn's disease

    International Nuclear Information System (INIS)

    The total body potassium (TBK), serum potassium, and the number of red blood cell ouabain-binding sites was studied in 94 patients with Crohn's diease. TBK was measured by counting the endogenous 40K in a whole body counter. TBK was 87%+-13% in 94 patients was Crohn's disease, while in control subjects, it was 97%+-12% (n=24). This significant reduction in TBK was accompanied by normal serum potassium levels (4.4+-0.5 mM). TBK was significantly correlated with the Crohn's disease activity index (r=0.79, n=113, P3H-ouabain showed a significant increse in the number of Na-K pumps in Crohn's disease (396+-65, n=27) compared with the control group. 290+-45 (n=24). These results support the suggestion that changes in TBK may regulate the synthesis of Na-K pump molecules. The total body potassium depletion and the need for a preoperative nutritional support in Crohn's disease are discussed. (orig.)

  3. Plasma guanidino compounds are altered by oral creatine supplementation in healthy humans.

    Science.gov (United States)

    Derave, Wim; Marescau, Bart; Vanden Eede, Els; Eijnde, Bert O; De Deyn, Peter P; Hespel, Peter

    2004-09-01

    Although creatine is one of the most widely used nutritional supplements for athletes as well as for patients with neuromuscular disorders, the effects of oral creatine supplementation on endogenous creatine synthesis in humans remains largely unexplored. The aim of the present study was to investigate the metabolic consequences of a frequently used, long-term creatine ingestion protocol on the circulating creatine synthesis precursor molecules, guanidinoacetate and arginine, and their related guanidino compounds. For this purpose, 16 healthy young volunteers were randomly divided to ingest in a double-blind fashion either creatine monohydrate or placebo (maltodextrine) at a dosage of 20 g/day for the first week (loading phase) and 5 g/day for 19 subsequent wk (maintenance phase). Fasting plasma samples were taken at baseline and at 1, 10, and 20 wk of supplementation, and guanidino compounds were determined. Plasma guanidinoacetate levels were reduced by 50% after creatine loading and remained approximately 30% reduced throughout the maintenance phase. Several circulating guanidino compound levels were significantly altered after creatine loading but not during the maintenance phase: homoarginine (+35%), alpha-keto-delta-guanidinovaleric acid (+45%), and argininic acid (+75%) were increased, whereas guanidinosuccinate was reduced (-25%). The decrease in circulating guanidinoacetate levels suggests that exogenous supply of creatine chronically inhibits endogenous synthesis at the transamidinase step in humans, supporting earlier animal studies showing a powerful repressive effect of creatine on l-arginine:glycine amidinotransferase. Furthermore, these data suggest that this leads to enhanced utilization of arginine as a substrate for secondary pathways. PMID:15107411

  4. Modulation of sulfated proteoglycan synthesis by bovine aortic endothelial cells during migration

    OpenAIRE

    1986-01-01

    The rates of 35S-sulfate incorporation into proteoglycan were compared in multi-scratch wounded and confluent cultures of bovine aortic endothelial cells to determine whether proteoglycan synthesis is altered as cells are stimulated to migrate and proliferate. Incorporation was found to be stimulated in a time-dependent manner, reaching maximal levels 44-50 h after wounding, as cells migrated into wounded areas of the culture dish. Quantitative autoradiography of 35S- sulfate-labeled single-s...

  5. Synthesis document on the long life behavior of packages: reference operational document ''CSD-C'' 2004

    International Nuclear Information System (INIS)

    This document is realized in the framework of the law of 1991 on the radioactive wastes management. The 2004 synthesis document on long time behavior of standard packages of compacted wastes is constituted by two documents, the reference document and the operational document. This paper presents the operational model describing the packages alteration by the water and the associated radionuclide release. (A.L.B.)

  6. Synthesis document on the long time behavior of packages: operational document ''bituminous'' 2204

    International Nuclear Information System (INIS)

    This document is realized in the framework of the law of 1991 on the radioactive wastes management. The 2004 synthesis document on long time behavior of bituminous sludges packages is constituted by two documents, the reference document and the operational document. This paper presents the operational model describing the water alteration of the packages and the associated radioelements release, as the gas term source and the swelling associated to the self-irradiation and the bituminous radiolysis. (A.L.B.)

  7. Thermodynamic investigations of microbial metabolism and abiotic organic synthesis in seafloor hydrothermal systems

    OpenAIRE

    Hentscher, Michael

    2012-01-01

    Hydrothermal circulation of seawater within the oceanic crust creates conditions suitable for chemosynthesis-based microbial life. Synthesis of abiotic organic compounds takes place during seawater-basement rock interaction at elevated temperatures. Low temperature circulation in the recharge zone allows chemolithoautotrophs to gain energy by oxidizing or reduction of minerals, while deeper and hotter regions (reaction zone) are dominated by rock alteration and produce the reduced conditions ...

  8. Synthesis of Methylaluminoxane

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Methylaluminoxane (MAO) is the most important cocatalyst of metallocene catalysts. In order to raise the hydrolysis reactions repeatability and the yield,we used the pretreated A12(SO4)3 18H2O to synthesize MAO. A few factors which influence the yield and the cocatalytic activity of MAO were discussed. The optimum condition of the reaction was obtained. The yield of MAO was raised from 40% to 49%. Synthesis of MAO: All the apparatus used was oven dried overnight and cooled under highly pure nitrogen atmosphere before use. The synthesis of MAO is carried out according to the procedure described below. 2M TMA/toluene solution was placed in a 200ml pressure balanced funnel. In a tluee necked 500ml round bottomed flask equipped with a teflon magnetic bar, the pretreated A12(SO4)3.18H2O was dispersed in dry toluene. The first neck was fitted with the pressure balanced funnel with a nitrogen outlet. The second neck was connected to nitrogen inlet. The third neck was connected to a thermowell.

  9. Synthesis of Methylaluminoxane

    Institute of Scientific and Technical Information of China (English)

    ZHU; BoChao

    2001-01-01

    Methylaluminoxane (MAO) is the most important cocatalyst of metallocene catalysts. In order to raise the hydrolysis reactions repeatability and the yield,we used the pretreated A12(SO4)3 18H2O to synthesize MAO. A few factors which influence the yield and the cocatalytic activity of MAO were discussed. The optimum condition of the reaction was obtained. The yield of MAO was raised from 40% to 49%.  Synthesis of MAO: All the apparatus used was oven dried overnight and cooled under highly pure nitrogen atmosphere before use. The synthesis of MAO is carried out according to the procedure described below.   2M TMA/toluene solution was placed in a 200ml pressure balanced funnel. In a tluee necked 500ml round bottomed flask equipped with a teflon magnetic bar, the pretreated A12(SO4)3.18H2O was dispersed in dry toluene. The first neck was fitted with the pressure balanced funnel with a nitrogen outlet. The second neck was connected to nitrogen inlet. The third neck was connected to a thermowell.  ……

  10. Synthesis of Lysophospholipids

    Directory of Open Access Journals (Sweden)

    Paola D’Arrigo

    2010-03-01

    Full Text Available New synthetic methods for the preparation of biologically active phospholipids and lysophospholipids (LPLs are very important in solving problems of membrane–chemistry and biochemistry. Traditionally considered just as second-messenger molecules regulating intracellular signalling pathways, LPLs have recently shown to be involved in many physiological and pathological processes such as inflammation, reproduction, angiogenesis, tumorogenesis, atherosclerosis and nervous system regulation. Elucidation of the mechanistic details involved in the enzymological, cell-biological and membrane-biophysical roles of LPLs relies obviously on the availability of structurally diverse compounds. A variety of chemical and enzymatic routes have been reported in the literature for the synthesis of LPLs: the enzymatic transformation of natural glycerophospholipids (GPLs using regiospecific enzymes such as phospholipases A1 (PLA1, A2 (PLA2 phospholipase D (PLD and different lipases, the coupling of enzymatic processes with chemical transformations, the complete chemical synthesis of LPLs starting from glycerol or derivatives. In this review, chemo-enzymatic procedures leading to 1- and 2-LPLs will be described.

  11. Oxygenates vs. synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Kamil Klier; Richard G. Herman; Alessandra Beretta; Maria A. Burcham; Qun Sun; Yeping Cai; Biswanath Roy

    1999-04-01

    Methanol synthesis from H{sub 2}/CO has been carried out at 7.6 MPa over zirconia-supported copper catalysts. Catalysts with nominal compositions of 10/90 mol% and 30/70 mol% Cu/ZrO{sub 2} were used in this study. Additionally, a 3 mol% cesium-doped 10/90 catalyst was prepared to study the effect of doping with heavy alkali, and this promoter greatly increased the methanol productivity. The effects of CO{sub 2} addition, water injection, reaction temperature, and H{sub 2}/C0 ratio have been investigated. Both CO{sub 2} addition to the synthesis gas and cesium doping of the catalyst promoted methanol synthesis, while inhibiting the synthesis of dimethyl ether. Injection of water, however, was found to slightly suppress methanol and dimethyl ether formation while being converted to CO{sub 2} via the water gas shift reaction over these catalysts. There was no clear correlation between copper surface area and catalyst activity. Surface analysis of the tested samples revealed that copper tended to migrate and enrich the catalyst surface. The concept of employing a double-bed reactor with a pronounced temperature gradient to enhance higher alcohol synthesis was explored, and it was found that utilization of a Cs-promoted Cu/ZnO/Cr{sub 2}O{sub 3} catalyst as a first lower temperature bed and a Cs-promoted ZnO/Cr{sub 2}O{sub 3} catalyst as a second high-temperature bed significantly promoted the productivity of 2-methyl-1-propanol (isobutanol) from H{sub 2}/CO synthesis gas mixtures. While the conversion of CO to C{sub 2+} oxygenates over the double-bed configuration was comparable to that observed over the single Cu-based catalyst, major changes in the product distribution occurred by the coupling to the zinc chromite catalyst; that is, the productivity of the C{sub 1}-C{sub 3} alcohols decreased dramatically, and 2-methyl branched alcohols were selectively formed. The desirable methanol/2-methyl oxygenate molar ratios close to 1 were obtained in the present double

  12. Near-field/altered-zone models report

    Energy Technology Data Exchange (ETDEWEB)

    Hardin, E. L., LLNL

    1998-03-01

    nonlithophysal and lower lithophysal units. These units are made up of moderately to densely welded, devitrified, fractured tuff. The rock's chemical composition is comparable to that of typical granite, but has textural features and mineralogical characteristics of large-scale, silicic volcanism. Because the repository horizon will be approximately 300 m below the ground surface and 200 m above the water table, the repository will be partially saturated. The welded tuff matrix in the host units is highly impermeable, but water and gas flow readily through fractures. The degree of fracturing in these units is highly variable, and the hydrologic significance of fracturing is an important aspect of site investigation. This report describes the characterization and modeling of a region around the potential repository--the altered zone--a region in which the temperature will be increased significantly by waste-generated heat. Numerical simulation has shown that, depending on the boundary conditions, rock properties, and repository design features incorporated in the models, the altered zone (AZ) may extend from the water table to the ground surface. This report also describes models of the near field, the region comprising the repository emplacement drifts and the surrounding rock, which are critical to the performance of engineered components. Investigations of near-field and altered-zone (NF/AZ) processes support the design of underground repository facilities and engineered barriers and also provide constraint data for probabilistic calculations of waste-isolation performance (i.e., performance assessment). The approach to investigation, which is an iterative process involving hypothesis testing and experimentation, has relied on conceptualizing engineered barriers and on performance analysis. This report is a collection, emphasizing conceptual and numerical models, of the recent results contributed from studies of NF/AZ processes and of quantitative measures of NF

  13. Near-field/altered-zone models report

    International Nuclear Information System (INIS)

    lithophysal units. These units are made up of moderately to densely welded, devitrified, fractured tuff. The rock's chemical composition is comparable to that of typical granite, but has textural features and mineralogical characteristics of large-scale, silicic volcanism. Because the repository horizon will be approximately 300 m below the ground surface and 200 m above the water table, the repository will be partially saturated. The welded tuff matrix in the host units is highly impermeable, but water and gas flow readily through fractures. The degree of fracturing in these units is highly variable, and the hydrologic significance of fracturing is an important aspect of site investigation. This report describes the characterization and modeling of a region around the potential repository--the altered zone--a region in which the temperature will be increased significantly by waste-generated heat. Numerical simulation has shown that, depending on the boundary conditions, rock properties, and repository design features incorporated in the models, the altered zone (AZ) may extend from the water table to the ground surface. This report also describes models of the near field, the region comprising the repository emplacement drifts and the surrounding rock, which are critical to the performance of engineered components. Investigations of near-field and altered-zone (NF/AZ) processes support the design of underground repository facilities and engineered barriers and also provide constraint data for probabilistic calculations of waste-isolation performance (i.e., performance assessment). The approach to investigation, which is an iterative process involving hypothesis testing and experimentation, has relied on conceptualizing engineered barriers and on performance analysis. This report is a collection, emphasizing conceptual and numerical models, of the recent results contributed from studies of NF/AZ processes and of quantitative measures of NF/AZ performance. The selection and

  14. Genetic alterations and epigenetic changes in hepatocarcinogenesis

    Directory of Open Access Journals (Sweden)

    Luz Stella Hoyos Giraldo

    2007-02-01

    Full Text Available

    Hepatocarcinogenesis as hepatocellular carcinoma (HCC is associated with background of chronic liver disease usually in association with cirrhosis, marked hepatic fibrosis, hepatitis B virus (HBV and/or hepatitis virus (HCV infection, chronic inflammation, Aflatoxin B1(AFB1 exposure, chronic alcoholism, metabolic disorder of the liver and necroinflamatory liver disease. Hepatocarcinogenesis involve two mechanisms, genetic alterations (with changes in the cell's DNA sequence and epigenetic changes (without changes in the cell's DNA sequence, but changes in the pattern of gene expression that can persist through one or more generations (somatic sense. Hepatocarcinogenesis is associated with activation of oncogenes and decreased expression of tumor suppressor genes (TSG; include those involved in cell cycle control, apoptosis, DNA repair, immortalization and angiogenesis. AFB1 is metabolized in the liver into a potent carcinogen, aflatoxin 8, 9-epoxide, which is detoxified by epoxide hydrolase (EPHX and glutathione S-transferase M1 (GSTM1.

    A failure of detoxification processes can allow to mutagenic metabolite to bind to DNA and inducing P53 mutation. Genetic polymorphism of EPHX and GSTM1 can make individuals more susceptible to AFB1. Epigenetic inactivation of GSTP1 by promoter hypermethylation plays a role in the development of HCC because, it leads that electrophilic metabolite increase DNA damage and mutations. HBV DNA integration into the host chromosomal DNA of hepatocytes has been detected in HBV-related HCC.

    DNA tumor viruses cause cancer mainly by interfering with cell cycle controls, and activating the cell's replication machinery by blocking the action of key TSG. HBx protein is a

  15. Pyrogenic organic matter can alter microbial communication

    Science.gov (United States)

    Masiello, Caroline; Gao, Xiaodong; Cheng, Hsiao-Ying; Silberg, Jonathan

    2016-04-01

    Soil microbes communicate with each other to manage a large range of processes that occur more efficiently when microbes are able to act simultaneously. This coordination occurs through the continuous production of signaling compounds that are easily diffused into and out of cells. As the number of microbes in a localized environment increases, the internal cellular concentration of these signaling compounds increases, and when a threshold concentration is reached, gene expression shifts, leading to altered (and coordinated) microbial behaviors. Many of these coordinated behaviors have biogeochemically important outcomes. For example, methanogenesis, denitrification, biofilm formation, and the development of plant-rhizobial symbioses are all regulated by a simple class of cell-cell signaling molecules known as acyl homoserine lactones (AHLs). Pyrogenic organic matter in soils can act to disrupt microbial communication through multiple pathways. In the case of AHLs, charcoal's very high surface area can sorb these signaling compounds, preventing microbes from detecting each others' presence (Masiello et al., 2014). In addition, the lactone ring in AHLs is vulnerable to pH increases accompanying PyOM inputs, with soil pH values higher than 7-8 leading to ring opening and compound destabilization. Different microbes use different classes of signaling compounds, and not all microbial signaling compounds are pH-vulnerable. This implies that PyOM-driven pH increases may trigger differential outcomes for Gram negative bacteria vs fungi, for example. A charcoal-driven reduction in microbes' ability to detect cell-cell communication compounds may lead to a shift in the ability of microbes to participate in key steps of C and N cycling. For example, an increase in an archaeon-specific AHL has been shown to lead to a cascade of metabolic processes that eventually results in the upregulation of CH4 production (Zhang et al., 2012). Alterations in similar AHL compounds leads to

  16. Towards Automated System Synthesis Using SCIDUCTION

    OpenAIRE

    Jha, Susmit Kumar

    2011-01-01

    Automated synthesis of systems that are correct by construction has been a long-standing goal of computer science. Synthesis is a creative task and requires human intuition and skill. Its complete automation is currently beyond the capacity of programs that do automated reasoning. However, there is a pressing need for tools and techniques that can automate non-intuitive and error-prone synthesis tasks. This thesis proposes a novel synthesis approach to solve such tasks in the synthesis of pro...

  17. Mice deficient in transmembrane prostatic acid phosphatase display increased GABAergic transmission and neurological alterations.

    Directory of Open Access Journals (Sweden)

    Heidi O Nousiainen

    Full Text Available Prostatic acid phosphatase (PAP, the first diagnostic marker and present therapeutic target for prostate cancer, modulates nociception at the dorsal root ganglia (DRG, but its function in the central nervous system has remained unknown. We studied expression and function of TMPAP (the transmembrane isoform of PAP in the brain by utilizing mice deficient in TMPAP (PAP-/- mice. Here we report that TMPAP is expressed in a subpopulation of cerebral GABAergic neurons, and mice deficient in TMPAP show multiple behavioral and neurochemical features linked to hyperdopaminergic dysregulation and altered GABAergic transmission. In addition to increased anxiety, disturbed prepulse inhibition, increased synthesis of striatal dopamine, and augmented response to amphetamine, PAP-deficient mice have enlarged lateral ventricles, reduced diazepam-induced loss of righting reflex, and increased GABAergic tone in the hippocampus. TMPAP in the mouse brain is localized presynaptically, and colocalized with SNARE-associated protein snapin, a protein involved in synaptic vesicle docking and fusion, and PAP-deficient mice display altered subcellular distribution of snapin. We have previously shown TMPAP to reside in prostatic exosomes and we propose that TMPAP is involved in the control of GABAergic tone in the brain also through exocytosis, and that PAP deficiency produces a distinct neurological phenotype.

  18. Alterations in Some Haematological Parameters of The African Snakehead: Parachanna africans Exposed to Cadmium

    Directory of Open Access Journals (Sweden)

    Ovie KORI-SAKPERE

    2011-11-01

    Full Text Available The haematological alterations produced on exposure of the African snakehead, Parachanna africans to the sublethal concentration (0.0, 0.1, 1.0 and 10.0 mg/L of cadmium (Cd2+ for 21 days have been studied. Red blood cell (RBC count, haemoglobin (Hb concentration, haematocrit (Hct, the mean corpuscular haemoglobin (MCH and the mean corpuscular volume (MCV levels were decreased with an increase in exposure concentration, but the level of the mean corpuscular haemoglobin concentration (MCHC was increased. These alterations could be attributed to haemolysis and impairment of haemoglobin synthesis, resulting in a hypochromic microcytic anaemia, induced by exposure to cadmium. Cadmium exposure also caused significant decreases in white blood cell (WBC count. The primary consequence of the observed changes in total and differential leucocyte counts in stressed fish was attributed to suppression of the immune system and increased susceptibility to disease. Plasma glucose and total plasma protein concentrations were significantly decreased; showing that cadmium affects the fish energy metabolism. The present study thus confirmed that haematological parameters are very sensitive indicators of fish organism response to chemicals in this case cadmium.

  19. Modification of collagen IV by glucose or methylglyoxal alters distinct mesangial cell functions.

    Science.gov (United States)

    Pozzi, Ambra; Zent, Roy; Chetyrkin, Sergei; Borza, Corina; Bulus, Nada; Chuang, Peale; Chen, Dong; Hudson, Billy; Voziyan, Paul

    2009-10-01

    Diabetic nephropathy (DN) affects both glomerular cells and the extracellular matrix (ECM), yet the pathogenic mechanisms involving cell-matrix interactions are poorly understood. Glycation alters integrin-dependent cell-ECM interactions, and perturbation of these interactions results in severe renal pathology in diabetic animals. Here, we investigated how chemical modifications of the ECM by hyperglycemia and carbonyl stress, two major features of the diabetic milieu, affect mesangial cell functions. Incubation of collagen IV with pathophysiological levels of either the carbonyl compound methylglyoxal (MGO) or glucose resulted in modification of arginine or lysine residues, respectively. Mouse mesangial cells plated on MGO-modified collagen IV showed decreased adhesion and migration. Cells plated on glucose-modified collagen IV showed reduced proliferation and migration and increased collagen IV production. Inhibiting glucose-mediated oxidative modification of collagen IV lysine residues rescued the alterations in cell growth, migration, and collagen synthesis. We propose that diabetic ECM affects mesangial cell functions via two distinct mechanisms: modification of arginine residues by MGO inhibits cell adhesion, whereas oxidative modification of lysine residues by glucose inhibits cell proliferation and increases collagen IV production. These mechanisms may contribute to mesangial cell hypertrophy and matrix expansion in DN. PMID:19608705

  20. High glucose alters retinal astrocytes phenotype through increased production of inflammatory cytokines and oxidative stress.

    Directory of Open Access Journals (Sweden)

    Eui Seok Shin

    Full Text Available Astrocytes are macroglial cells that have a crucial role in development of the retinal vasculature and maintenance of the blood-retina-barrier (BRB. Diabetes affects the physiology and function of retinal vascular cells including astrocytes (AC leading to breakdown of BRB. However, the detailed cellular mechanisms leading to retinal AC dysfunction under high glucose conditions remain unclear. Here we show that high glucose conditions did not induce the apoptosis of retinal AC, but instead increased their rate of DNA synthesis and adhesion to extracellular matrix proteins. These alterations were associated with changes in intracellular signaling pathways involved in cell survival, migration and proliferation. High glucose conditions also affected the expression of inflammatory cytokines in retinal AC, activated NF-κB, and prevented their network formation on Matrigel. In addition, we showed that the attenuation of retinal AC migration under high glucose conditions, and capillary morphogenesis of retinal endothelial cells on Matrigel, was mediated through increased oxidative stress. Antioxidant proteins including heme oxygenase-1 and peroxiredoxin-2 levels were also increased in retinal AC under high glucose conditions through nuclear localization of transcription factor nuclear factor-erythroid 2-related factor-2. Together our results demonstrated that high glucose conditions alter the function of retinal AC by increased production of inflammatory cytokines and oxidative stress with significant impact on their proliferation, adhesion, and migration.

  1. Altered gene regulation and synaptic morphology in Drosophila learning and memory mutants.

    Science.gov (United States)

    Guan, Zhuo; Buhl, Lauren K; Quinn, William G; Littleton, J Troy

    2011-01-01

    Genetic studies in Drosophila have revealed two separable long-term memory pathways defined as anesthesia-resistant memory (ARM) and long-lasting long-term memory (LLTM). ARM is disrupted in radish (rsh) mutants, whereas LLTM requires CREB-dependent protein synthesis. Although the downstream effectors of ARM and LLTM are distinct, pathways leading to these forms of memory may share the cAMP cascade critical for associative learning. Dunce, which encodes a cAMP-specific phosphodiesterase, and rutabaga, which encodes an adenylyl cyclase, both disrupt short-term memory. Amnesiac encodes a pituitary adenylyl cyclase-activating peptide homolog and is required for middle-term memory. Here, we demonstrate that the Radish protein localizes to the cytoplasm and nucleus and is a PKA phosphorylation target in vitro. To characterize how these plasticity pathways may manifest at the synaptic level, we assayed synaptic connectivity and performed an expression analysis to detect altered transcriptional networks in rutabaga, dunce, amnesiac, and radish mutants. All four mutants disrupt specific aspects of synaptic connectivity at larval neuromuscular junctions (NMJs). Genome-wide DNA microarray analysis revealed ∼375 transcripts that are altered in these mutants, suggesting defects in multiple neuronal signaling pathways. In particular, the transcriptional target Lapsyn, which encodes a leucine-rich repeat cell adhesion protein, localizes to synapses and regulates synaptic growth. This analysis provides insights into the Radish-dependent ARM pathway and novel transcriptional targets that may contribute to memory processing in Drosophila. PMID:21422168

  2. Tumor promoters alter gene expression and protein phosphorylation in avian cells in culture

    International Nuclear Information System (INIS)

    We have investigated the effect of 12-O-tetradecanoylphorbol 13-acetate (TPA) on the synthesis and modification of polypeptides in normal avian cells and cells infected by wild-type and temperature-sensitive Rous sarcoma virus (RSV). Using two-dimensional gel electrophoresis, we have detected alterations in both the abundance of cellular polypeptides and in their phosphorylation that seem unique to TPA treatment. However, the state of phosphorylation of the major putative substrate for the action of the src gene-associated protein kinase, the 34- to 36-kilodalton protein, was not altered. Moreover, examination of the phosphorylated amino acid content of total cellular phosphoproteins revealed that the response to TPA was not associated with detectable increases in their phosphotyrosine content. These results make it unlikely that TPA acts by the activation of the phosphorylating activity of the cellular proto-src gene or by the activation of other cellular phosphotyrosine-specific kinases. We have shown previously that temperature-sensitive RSV-infected cells at nonpermissive temperature demonstrate an increased sensitivity to TPA treatment [Bissell, M.J., Hatie, C. and Calfin, M. (1979) Proc. Natl. Acad. Sci. USA 76, 348-352]. Our present results indicate that this is not due to reactivation of the phosphorylating activity of the defective src gene product or to its leakiness, and they lend support to the notion of multistep viral carcinogenesis

  3. Basaltic glass: alteration mechanisms and analogy with nuclear waste glasses

    International Nuclear Information System (INIS)

    A synthetic basaltic glass was dissolved experimentally at 90 deg. C under static conditions in initially pure water. The basaltic glass dissolution rates measured near and far from equilibrium were compared with those of SON 68 nuclear waste glass. Experimental and literature data notably suggested that the alteration mechanisms for the two glasses are initially similar. Under steady-state concentration conditions, the alteration rate decreased of four orders of magnitude below the initial rate (r0). The same alteration rate decrease was observed for basaltic and nuclear glass. These findings tend to corroborate the analogy of the two glasses alteration kinetics. The effect of dissolved silica in solution, observed through dynamic leach tests with silicon-rich solutions, cannot account for the significant drop in the basaltic glass kinetics. Hence, a protective effect of the glass alteration film was assumed and experimentally investigated. Moreover, modeling with LIXIVER argue for a significant effect of diffusion in the alteration gel

  4. Brain alterations in paedophilia: a critical review.

    Science.gov (United States)

    Mohnke, Sebastian; Müller, Sabine; Amelung, Till; Krüger, Tillmann H C; Ponseti, Jorge; Schiffer, Boris; Walter, Martin; Beier, Klaus M; Walter, Henrik

    2014-11-01

    Psychosocial and biological factors have been implicated in paedophilia, such as alterations in brain structure and function. The purpose of this paper is to review the expanding body of literature on this topic including brain abnormality case reports, as well as structural and functional neuroimaging studies. Case studies of men who have committed sexual offences against children implicate frontal and temporal abnormalities that may be associated with impaired impulse inhibition. Structural neuroimaging investigations show volume reductions in paedophilic men. Although the findings have been heterogeneous, smaller amygdala volume has been replicated repeatedly. Functional neuroimaging investigations demonstrate an overlap between paedophiles and teleiophiles during sexual arousal processing. While it is controversial among studies regarding group differences, reliable discrimination between paedophilic and teleiophilic men may be achieved using functional activation patterns. Nevertheless, the heterogeneous findings published so far suggest further research is necessary to disentangle the neurobiological mechanisms of paedophilic preference. A number of methodological confounds have been identified, which may account for the inconsistent results that could prove to be beneficial for future investigations. PMID:25116710

  5. Plant growth conditions alter phytolith carbon

    Directory of Open Access Journals (Sweden)

    Kimberley L Gallagher

    2015-09-01

    Full Text Available Many plants, including grasses and some important human food sources, accumulate and precipitate silica in their cells to form opaline phytoliths. These phytoliths contain small amounts of organic matter (OM that are trapped during the process of silicification. Previous work has suggested that plant silica is associated with compounds such as proteins, lipids, lignin and carbohydrate complexes. It is not known whether these compounds are cellular components passively encapsulated as the cell silicifies, polymers actively involved in the precipitation process or random compounds assimilated by the plant and discarded into a glass wastebasket. Here, we used Raman spectroscopy to map the distribution of OM in phytoliths, and to analyze individual phytoliths isolated from Sorghum bicolor plants grown under different laboratory treatments. Using mapping, we showed that OM in phytoliths is distributed throughout the silica and is not related to dark spots visible in light microscopy, previously assumed to be the repository for phytolith OM. The Raman spectra exhibited common bands indicative of C-H stretching modes of general OM, and further more diagnostic bands consistent with carbohydrates, lignins and other OM. These Raman spectra exhibited variability of spectral signatures and of relative intensities between sample treatments indicating that differing growth conditions altered the phytolith carbon. This may have strong implications for understanding the mechanism of phytolith formation, and for use of phytolith carbon isotope values in dating or paleoclimate reconstruction.

  6. Genomic and epigenomic alterations in prostate cancer

    Directory of Open Access Journals (Sweden)

    Anna Maria eAschelter

    2012-11-01

    Full Text Available Prostate cancer (PC is the second most frequently diagnosed cancer and the second leading cause of cancer deaths in man. The treatment of localized PC includes surgery or radiation therapy. In case of relapse after a definitive treatment or in patients with locally advanced or metastatic disease, the standard treatment includes the androgen-deprivation therapy (ADT. By reducing the levels of Testosterone and dihydrotestosterone (DHT under the castration threshold, the ADT acts on the androgen receptor (AR, even if indirectly. The effects of the ADT are usually temporary and nearly all patients, initially sensitive to the androgen ablation therapy, have a disease progression after a 18-24 months medium term. This is probably due to the selection of the cancer cell clones and to their acquisition of critical somatic genome and epigenomic changes. This review aims to provide an overview about the genetic and epigenetic alterations having a crucial role in the carcinogenesis and in the disease progression toward the castration resistant prostate cancer (CRPC. We focused on the role of the androgen receptor, on its signaling cascade and on the clinical implications that the knowledge of these aspects would have on hormonal therapy, on its failure and its toxicity.

  7. Ictal alterations of consciousness during ecstatic seizures.

    Science.gov (United States)

    Picard, Fabienne; Kurth, Florian

    2014-01-01

    Patients with ecstatic epileptic seizures report an altered consciousness, which they describe as a sense of heightened perception of themselves – they “feel very present” – and an increased vividness of sensory perceptions. Recently, the anterior insula has been proposed as the region where these seizures originate, based on the results of ictal nuclear imaging in three patients, the first induction of ecstatic auras by electrical stimulation, and the functional characteristics of the anterior insula in neuroimaging literature. Specifically, the anterior insula is thought to play a key role in integrating information from within the body, the external world, as well as the emotional states. In addition, the anterior insula is thought to convert this integrated information into successive global emotional moments, thus enabling both the construct of a sentient self as well as a mechanism for predictive coding. As part of the salience network, this region is also involved in switching from mind wandering toward attentional and executive processing. In this review, we will summarize previous patient reports and recap how insular functioning may be involved in the phenomenon of ecstatic seizures. Furthermore, we will relate these hypotheses to the results from research on meditation and effects of drug abuse. PMID:24436968

  8. Altering Emulsion Stability with Heterogeneous Surface Wettability

    Science.gov (United States)

    Meng, Qiang; Zhang, Yali; Li, Jiang; Lammertink, Rob G. H.; Chen, Haosheng; Tsai, Peichun Amy

    2016-06-01

    Emulsions–liquid droplets dispersed in another immiscible liquid–are widely used in a broad spectrum of applications, including food, personal care, agrochemical, and pharmaceutical products. Emulsions are also commonly present in natural crude oil, hampering the production and quality of petroleum fuels. The stability of emulsions plays a crucial role in their applications, but controlling the stability without external driving forces has been proven to be difficult. Here we show how heterogeneous surface wettability can alter the stability and dynamics of oil-in-water emulsions, generated by a co-flow microfluidic device. We designed a useful methodology that can modify a micro-capillary of desired heterogeneous wettability (e.g., alternating hydrophilic and hydrophobic regions) without changing the hydraulic diameter. We subsequently investigated the effects of flow rates and heterogeneous wettability on the emulsion morphology and motion. The experimental data revealed a universal critical timescale of advective emulsions, above which the microfluidic emulsions remain stable and intact, whereas below they become adhesive or inverse. A simple theoretical model based on a force balance can be used to explain this critical transition of emulsion dynamics, depending on the droplet size and the Capillary number–the ratio of viscous to surface effects. These results give insight into how to control the stability and dynamics of emulsions in microfluidics with flow velocity and different wettability.

  9. Radiofrequency treatment alters cancer cell phenotype

    Science.gov (United States)

    Ware, Matthew J.; Tinger, Sophia; Colbert, Kevin L.; Corr, Stuart J.; Rees, Paul; Koshkina, Nadezhda; Curley, Steven; Summers, H. D.; Godin, Biana

    2015-07-01

    The importance of evaluating physical cues in cancer research is gradually being realized. Assessment of cancer cell physical appearance, or phenotype, may provide information on changes in cellular behavior, including migratory or communicative changes. These characteristics are intrinsically different between malignant and non-malignant cells and change in response to therapy or in the progression of the disease. Here, we report that pancreatic cancer cell phenotype was altered in response to a physical method for cancer therapy, a non-invasive radiofrequency (RF) treatment, which is currently being developed for human trials. We provide a battery of tests to explore these phenotype characteristics. Our data show that cell topography, morphology, motility, adhesion and division change as a result of the treatment. These may have consequences for tissue architecture, for diffusion of anti-cancer therapeutics and cancer cell susceptibility within the tumor. Clear phenotypical differences were observed between cancerous and normal cells in both their untreated states and in their response to RF therapy. We also report, for the first time, a transfer of microsized particles through tunneling nanotubes, which were produced by cancer cells in response to RF therapy. Additionally, we provide evidence that various sub-populations of cancer cells heterogeneously respond to RF treatment.

  10. Foveal Thickness Alterations in Patients with Migraine

    Science.gov (United States)

    Cankaya, Cem; Tecellioglu, Mehmet

    2016-01-01

    Aim: To investigate the alterations in foveal retinal thickness (FT) values in patients with migraine and to reveal the correlations between FT and clinical characteristics of migraine disease. Methods: This study included sixty-eight eyes of 34 migraine patients [twenty-eight eyes of 14 patients with aura (group 1), and forty eyes of 20 patients without aura (group 2)] and forty eyes of 20 healthy volunteer who served as the control group (group 3). FT values were measured by optical coherence tomography (OCT) in each group. Results: Mean age of patients in group 1, 2, and 3 was 34.0± 6.82, 35.2±10.12, and 35.1± 6.85 years, respectively (p=0.84). Mean FT was 211.07±7.36, 220.0±12.01, and 221.85±12.27 in groups 1, 2, and 3, respectively. There was statistically significance among the group 1-2 and 1-3 (p=0.002 and pmigraine with aura may lead to a reduction in FT values. This finding can be explained by the blood flow decrease theory in migraine; however larger studies seem mandatory. PMID:27147787

  11. Pathogenic alteration in severe burn wounds.

    Science.gov (United States)

    Fu, Yang; Xie, Bing; Ben, DaoFeng; Lv, KaiYang; Zhu, ShiHui; Lu, Wei; Tang, HongTai; Cheng, DaSheng; Ma, Bing; Wang, GuangYi; Xiao, ShiChu; Wang, GuangQing; Xia, ZhaoFan

    2012-02-01

    The present study aims to define the trend of time related changes with local bacterial alteration of bacterial resistance in severe burns in our burn center during a 12-year period. Retrospective analysis of microbiological results on severely burned wounds between 1998 and 2009 was carried out. A study of 3615 microbial isolates was performed. Staphylococcus aureus was the most commonly isolated pathogen (38.2%) followed by A. baumannii (16.2%), Streptococcus viridans (11.4%), Pseudomonas aeruginosa (10.4%), coagulase-negative staphylococci (CNS, 9.2%). The species ratios of S. aureus and A. baumannii increased significantly from 1st to 8th week of hospitalization, while those of Streptococcus viridans, P. aeruginosa and coagulase-negative staphylococci decreased during the same period. Bacterial resistance rates were compared between the periods 1998-2003 and 2004-2009. Vancomycin remained as the most sensitive antibiotic in S. aureus including methicillin-resistant S. aureus (MRSA). It was very likely that the majority of infections caused by Streptococcus viridans, P. aeruginosa and coagulase-negative staphylococci occurred in the early stage of burn course and the majority of infections caused by A. baumannii occurred 4 weeks after admission. The use of different antibiotics was probably the major contributor to these trends. PMID:22100426

  12. Shadows alter facial expressions of Noh masks.

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kawai

    Full Text Available BACKGROUND: A Noh mask, worn by expert actors during performance on the Japanese traditional Noh drama, conveys various emotional expressions despite its fixed physical properties. How does the mask change its expressions? Shadows change subtly during the actual Noh drama, which plays a key role in creating elusive artistic enchantment. We here describe evidence from two experiments regarding how attached shadows of the Noh masks influence the observers' recognition of the emotional expressions. METHODOLOGY/PRINCIPAL FINDINGS: In Experiment 1, neutral-faced Noh masks having the attached shadows of the happy/sad masks were recognized as bearing happy/sad expressions, respectively. This was true for all four types of masks each of which represented a character differing in sex and age, even though the original characteristics of the masks also greatly influenced the evaluation of emotions. Experiment 2 further revealed that frontal Noh mask images having shadows of upward/downward tilted masks were evaluated as sad/happy, respectively. This was consistent with outcomes from preceding studies using actually tilted Noh mask images. CONCLUSIONS/SIGNIFICANCE: Results from the two experiments concur that purely manipulating attached shadows of the different types of Noh masks significantly alters the emotion recognition. These findings go in line with the mysterious facial expressions observed in Western paintings, such as the elusive qualities of Mona Lisa's smile. They also agree with the aesthetic principle of Japanese traditional art "yugen (profound grace and subtlety", which highly appreciates subtle emotional expressions in the darkness.

  13. Gestational dexamethasone alters fetal neuroendocrine axis.

    Science.gov (United States)

    Ahmed, R G

    2016-09-01

    This study tested whether the maternal transport of dexamethasone (DEXA) may affect the development of the neuroendocrine system. DEXA (0.2mg/kg b.w., subcutaneous injection) was administered to pregnant rats from gestation day (GD) 1-20. In the DEXA-treated group, a decrease in maternal serum thyroxine (T4), triiodothyronine (T3), and increase in thyrotropin (TSH) levels (hypothyroid status) were observed at GDs 15 & 20 with respect to control group. The reverse pattern (hyperthyroid status) was observed in their fetuses at embryonic days (EDs) 15 & 20. Although the maternal body weight was diminished, the weight of the thyroid gland was increased at studied GDs as compared to the control group. The fetal growth retardation, hyperleptinemia, hyperinsulinism, and cytokines distortions (transforming growth factor-beta; TGF-β, tumor necrosis factor-alpha; TNF-α, and interferon-γ; IFN-γ) were noticed at examined EDs if compared to the control group. Alternatively, the maternofetal thyroid dysfunctions due to the maternal DEXA administration attenuated the levels of fetal cerebral norepinephrine (NE) and epinephrine (E), and elevated the levels of dopamine (DA) and 5-hydroxytryptamine (5-HT) at considered days. These alterations were age-dependent and might damage the nerve transmission. Finally, maternal DEXA might act as neuroendocrine disruptor causing dyshormonogenesis and fetal cerebral dysfunction. PMID:27220267

  14. Microgravity alters cancer growth and progression.

    Science.gov (United States)

    Jhala, Dhwani V; Kale, Raosaheb K; Singh, Rana P

    2014-01-01

    Study of the process of cancer initiation, growth and progression in altered gravity is of utmost importance considering the health status of researchers visiting in space and future scope of space tourism. Microgravity affects various cells in the body differently; however, the mechanisms of such effects are not understood completely. Therefore, it is imperative to explore various physiological and biochemical processes, particularly those which can influence the process of carcinogenesis. If the changes in physiological or biochemical processes do not revert back to normalcy even after returning from the space to earth, it may lead to various aberrations and morphological changes during the life span. Such changes could lead to pathological conditions including cancer. For example, microgravity is observed to suppress the activity of immune cells, which itself increases the risk of cancer development. It is little known how the microgravity affects cellular and molecular events that determine physiological and biological responses. There is also a possibility of changes in epigenetic signatures during microgravity exposure which remains unexplored. Herein, we have reviewed the effect of microgravity on relevant molecular and biological processes, and how it could influence the course of cancer development. In this regard, we have also highlighted the areas of research that require more attention to bridge the gap of understanding for such biological processes. PMID:24720362

  15. Alterated integrin expression in lichen planopilaris

    Directory of Open Access Journals (Sweden)

    Erriquez Roberta

    2007-02-01

    Full Text Available Abstract Background Lichen planopilaris (LPP is an inflammatory disease characterized by a lymphomononuclear infiltrate surrounding the isthmus and infundibulum of the hair follicle of the scalp, that evolves into atrophic/scarring alopecia. In the active phase of the disease hairs are easily plucked with anagen-like hair-roots. In this study we focused on the expression of integrins and basement membrane components of the hair follicle in active LPP lesions. Methods Scalp biopsies were taken in 10 patients with LPP and in 5 normal controls. Using monoclonal antibodies against α3β1 and α6β4 integrins we showed the expression of these integrins and of the basement membrane components of the hair follicle in active LPP lesions and in healthy scalp skin. Results In the LPP involved areas, α3β1 was distributed in a pericellular pattern, the α6 subunit was present with a basolateral distribution while the β4 subunit showed discontinuous expression at the basal pole and occasionally, basolateral staining of the hair follicle. Conclusion: An altered distribution of the integrins in active LPP lesions can explain the phenomenon of easy pulling-out of the hair with a "gelatinous" root-sheath.

  16. Origin and significance of chromosomal alterations

    International Nuclear Information System (INIS)

    The spontaneous frequency of chromsomal changes (structural and numerical aberations) in humans is in the order of 6 in 1,000 newborn. Chromosomal analysis of spontaneous abortuses indicate that about 50% of all spontaneous abortions are chromsomally abnormal. Populations exposed to ionizing radiations (atom bomb survivors) or chemical mutagens (e.g., workers occupational.y exposed to vinyl chloride or benzene) show increased frequencies of chromosomal aberrations in their peripheral blood lymphocytes. Many types of human cancer are associated with specific or non-specific chromosomal aberrations. Several human recessive diseases, such as ataxia telangiectasia (A-T), Faconi's anemia (FA) and Bloom's syndrome (BS) are associated with increased frequencies of chromosomal aberrations. However, no detectable increase in the frequency of spontaneous point mutations in human populations exposed to ionizing radiations or chemical mutagens has been demonstrated so far. These observations point to the importance of understanding the mechanism involved in the origin of chromosomal alterations and their significance, which the author discusses in this paper

  17. Serum Protein Profile Alterations in Hemodialysis Patients

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, G A; Davies, R W; Choi, M W; Perkins, J; Turteltaub, K W; McCutchen-Maloney, S L; Langlois, R G; Curzi, M P; Trebes, J E; Fitch, J P; Dalmasso, E A; Colston, B W; Ying, Y; Chromy, B A

    2003-11-18

    Background: Serum protein profiling patterns can reflect the pathological state of a patient and therefore may be useful for clinical diagnostics. Here, we present results from a pilot study of proteomic expression patterns in hemodialysis patients designed to evaluate the range of serum proteomic alterations in this population. Methods: Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOFMS) was used to analyze serum obtained from patients on periodic hemodialysis treatment and healthy controls. Serum samples from patients and controls were first fractionated into six eluants on a strong anion exchange column, followed by application to four array chemistries representing cation exchange, anion exchange, metal affinity and hydrophobic surfaces. A total of 144 SELDI-TOF-MS spectra were obtained from each serum sample. Results: The overall profiles of the patient and control samples were consistent and reproducible. However, 30 well-defined protein differences were observed; 15 proteins were elevated and 15 were decreased in patients compared to controls. Serum from one patient exhibited novel protein peaks suggesting possible additional changes due to a secondary disease process. Conclusion: SELDI-TOF-MS demonstrated dramatic serum protein profile differences between patients and controls. Similarity in protein profiles among dialysis patients suggests that patient physiological responses to end-stage renal disease and/or dialysis therapy have a major effect on serum protein profiles.

  18. Synthesis through Trans-disciplinarity

    DEFF Research Database (Denmark)

    Hansen, Hanne Tine Ring

    2006-01-01

    When looking up the word ‘synthesis' in a dictionary, one comes across the following definition: "The combining of separate elements or substances to form a coherent whole."[1] Based on this definition one could argue that all great architectureis achieved through synthesis in one way or another...... consider how synthesis is a requirement for creating successful ‘environmentally sustainable' architecture through the application of trans-disciplinarity, which leads to an increased awareness of the differences in decision-making as well as that of communication barriers between the different professions...

  19. Chemoenzymatic synthesis of spinosyn A.

    Science.gov (United States)

    Kim, Hak Joong; Choi, Sei-hyun; Jeon, Byung-sun; Kim, Namho; Pongdee, Rongson; Wu, Qingquan; Liu, Hung-wen

    2014-12-01

    Following the biosynthesis of polyketide backbones by polyketide synthases (PKSs), post-PKS modifications result in a significantly elevated level of structural complexity that renders the chemical synthesis of these natural products challenging. We report herein a total synthesis of the widely used polyketide insecticide spinosyn A by exploiting the prowess of both chemical and enzymatic methods. As more polyketide biosynthetic pathways are characterized, this chemoenzymatic approach is expected to become readily adaptable to streamlining the synthesis of other complex polyketides with more elaborate post-PKS modifications. PMID:25287333

  20. Success journey of solvent synthesis

    International Nuclear Information System (INIS)

    Synthesis of solvents for the front and back end of nuclear fuel cycle is a major diversification activity of Heavy Water Board. HWP, Tuticorin had taken up synthesis of oreganophosphorous solvents TOPO, TAPO, DNPPA and TIAP. The basic synthesis routes were provided by NCL, Pune and BARC. HWP,Tuticorin has carried out no. of Lab and Bench Scale campaigns for modifying the process and optimizing the parameters. This resulted in increased purity and yield, reduction in batch time, reduction in cost of production and effluent generation. Finalization of design of a 500 litre Pilot Scale Reactor is underway. This will lead to the goal of setting up of Industrial Plant. (author)

  1. Altered regulation of lipid biosynthesis in a mutant of Arabidopsis deficient in chloroplast glycerol-3-phosphate acyltransferase activity

    International Nuclear Information System (INIS)

    The leaf membrane lipids of many plant species, including Arabidopsis thaliana (L.) Heynh., are synthesized by two complementary pathways that are associated with the chloroplast and the endoplasmic reticulum. By screening directly for alterations in lipid acyl-group composition, the authors have identified several mutants of Arabidopsis that lack the plastid pathway because of a deficiency in activity of the first enzyme in the plastid pathway of glycerolipid synthesis, acyl-ACP:sn-glycerol-3-phosphate acyltransferase. The lesion results in an increased synthesis of lipids by the cytoplasmic pathway that largely compensates for the loss of the plastid pathway and provides nearly normal amounts of all the lipids required for chloroplast biogenesis. However, the fatty acid composition of the leaf membrane lipids of the mutants is altered because the acyltransferases associated with the two pathways normally exhibit different substrate specificities. The remarkable flexibility of the system provides an insight into the nature of the regulatory mechanisms that allocate lipids for membrane biogenesis

  2. Altered myoelectric activity in the experimental blind loop syndrome.

    OpenAIRE

    Justus, P G; Fernandez, A; Martin, J.L.; King, C E; Toskes, P P; Mathias, J R

    1983-01-01

    Nutrient malabsorption and diarrhea are characteristic of the blind loop syndrome. Alterations in motility have been implicated as a cause of bacterial overgrowth, but the possibility that altered motility may result from alterations in the flora has not been explored. The purpose of this study was to characterize the myoelectric activity of the small intestine in the blind loop rat model. Eight groups of rats were studied: rats with self-filling blind loops, which develop bacterial overgrowt...

  3. Altered States of Consciousness during an Extreme Ritual

    OpenAIRE

    Lee, Ellen M.; Klement, Kathryn R.; Ambler, James K.; Loewald, Tonio; Comber, Evelyn M.; Hanson, Sarah A.; Pruitt, Bria; Sagarin, Brad J.

    2016-01-01

    Extreme rituals (body-piercing, fire-walking, etc.) are anecdotally associated with altered states of consciousness—subjective alterations of ordinary mental functioning (Ward, 1984)—but empirical evidence of altered states using both direct and indirect measures during extreme rituals in naturalistic settings is limited. Participants in the “Dance of Souls”, a 3.5-hour event during which participants received temporary piercings with hooks or weights attached to the piercings and danced to m...

  4. Neuroinflammation and neurological alterations in chronic liver diseases

    OpenAIRE

    Carmina Montoliu; Marta Llansola; Vicente Felipo

    2015-01-01

    Several million people with chronic liver diseases (cirrhosis, hepatitis) show neurological alterations, named hepatic encephalopathy (HE) with cognitive and motor alterations that impair quality of life and reduces life span. Inflammation acts synergistically with hyperammonemia to induce cognitive and motor alterations in patients with chronic liver disease and minimal hepatic encephalopathy (MHE). Previous studies in animal models have suggested that neuroinflammation is a major player in ...

  5. Determining the relative extent of alteration in CM chondrites

    Science.gov (United States)

    Browning, Lauren B.; McSween, Harry Y., Jr.; Zolensky, Michael

    1993-03-01

    The aqueous alteration of CM chondrites provides a record of the processes attending the earliest stages of parent body evolution. However, resolving the alteration pathways of chondritic evolution requires a means for distinguishing the relative extent of alteration that individual samples have experienced. Three new indices for gauging the relative degree of alteration in CM chondrites based on modal and compositional analyses of 7 CM falls were proposed. The proposed alteration parameters are consistent with the basic tenets of several previous models and correlate with additional indices to produce an integrated method for determining the relative extent of alteration. The model predicts the following order of progressive alteration: Murchison (MC) is less than or equal to Bells (BL) is less than Murray (MY) is less than Cochabamba (CC) is less than Mighei (MI) is less than Nogoya (NG) is less than or equal to Cold Bokkeveld (CB). The broad range of CM phyllosilicate compositions observed within individual meteorites is fundamental to the characterization of the aqueous alteration process. Chemical analyses of CM phyllosilicates suggest that these phases became systematically enriched in Mg and depleted in Fe with increasing alteration.

  6. Synthesis of superhard materials

    Directory of Open Access Journals (Sweden)

    Vladimir L. Solozhenko

    2005-11-01

    Full Text Available The study of solids at high pressures and temperatures is an important area of modern condensed matter physics, chemistry, and materials science. The last decade has seen revolutionary developments in the field of high-pressure experimentation: new types of cells allow a wider range of experiments at higher pressures, and third-generation synchrotrons have brought the possibility of conducting X-ray diffraction experiments that were unthinkable only 10 years ago. In this review, we give some recent examples to illustrate how modern high-pressure tools, such as the diamond anvil cell (DAC, multianvil press, and shock compression, can be used to answer questions relevant to the synthesis of new advanced materials. Our examples will be related mostly to superhard materials.

  7. Combinatorial materials synthesis

    Directory of Open Access Journals (Sweden)

    Ichiro Takeuchi

    2005-10-01

    Full Text Available The pace at which major technological changes take place is often dictated by the rate at which new materials are discovered, and the timely arrival of new materials has always played a key role in bringing advances to our society. It is no wonder then that the so-called combinatorial or high-throughput strategy has been embraced by practitioners of materials science in virtually every field. High-throughput experimentation allows simultaneous synthesis and screening of large arrays of different materials. Pioneered by the pharmaceutical industry, the combinatorial method is now widely considered to be a watershed in accelerating the discovery and optimization of new materials1–5.

  8. Alteration kinetics of the glass-ceramic zirconolite and role of the alteration film Comparison with the SON68 glass

    Science.gov (United States)

    Martin, C.; Ribet, I.; Frugier, P.; Gin, S.

    2007-06-01

    The glass-ceramic zirconolite is being considered for specific conditioning of plutonium or the minor actinides. The actinides are distributed throughout the zirconolite crystals and the residual glass phase. Since zirconolite alteration is extremely limited, actinide release from the glass-ceramic material is mainly attributable to alteration of the residual glass. Specimens corresponding to the residual glass phase alone were therefore altered under different conditions to compare their kinetics with the one of the SON68 glass (inactive R7T7 type glass). Glass-ceramic zirconolite presents a more important rate decrease occuring more rapidly and that induces a quantity of glass altered at least 10 times as small as for SON68 glass. This slowdown of the alteration rate is attributed to the formation of an alteration film that has been the subject of a specific study. We have in particular identified a dense phase enriched in titanium and neodymium that probably influences deeply the kinetics.

  9. Instrument Synthesis and Analysis Laboratory

    Science.gov (United States)

    Wood, H. John

    2004-01-01

    The topics addressed in this viewgraph presentation include information on 1) Historic instruments at Goddard; 2) Integrated Design Capability at Goddard; 3) The Instrument Synthesis and Analysis Laboratory (ISAL).

  10. Total synthesis of solanoeclepin A

    Science.gov (United States)

    Tanino, Keiji; Takahashi, Motomasa; Tomata, Yoshihide; Tokura, Hiroshi; Uehara, Taketo; Narabu, Takashi; Miyashita, Masaaki

    2011-06-01

    Cyst nematodes are troublesome parasites that live on, and destroy, a range of important host vegetable plants. Damage caused by the potato cyst nematode has now been reported in over 50 countries. One approach to eliminating the problem is to stimulate early hatching of the nematodes, but key hatching stimuli are not naturally available in sufficient quantities to do so. Here, we report the first chemical synthesis of solanoeclepin A, the key hatch-stimulating substance for potato cyst nematode. The crucial steps in our synthesis are an intramolecular cyclization reaction for construction of the highly strained tricyclo[5.2.1.01,6]decane skeleton (DEF ring system) and an intramolecular Diels-Alder reaction of a furan derivative for the synthesis of the ABC carbon framework. The present synthesis has the potential to contribute to addressing one of the critical food issues of the twenty-first century.

  11. Vanillin Synthesis from 4-Hydroxybenzaldehyde

    Science.gov (United States)

    Taber, Douglass F.; Patel, Shweta; Hambleton, Travis M.; Winkel, Emma E.

    2007-01-01

    A regioselective, safe and efficient method for the synthesis of vanillin from 4-hydroxybenzaldehyde is being described. The vanillin derived from the process is cheap and can be used as a flavor or in the paper industry.

  12. Synthesis of perfluoroalkylated bulky triarylamines

    OpenAIRE

    Alameddine, Bassam; Savary, Corinne; Aebischer, Olivier; Jenny, Titus A

    2007-01-01

    The synthesis of two new triarylamine compounds bearing perfluoroalkylated side chains is described. Good thermal stabilities combined with a blue emission make these compounds promising candidates for materials applications.

  13. Green chemistry for nanoparticle synthesis.

    Science.gov (United States)

    Duan, Haohong; Wang, Dingsheng; Li, Yadong

    2015-08-21

    The application of the twelve principles of green chemistry in nanoparticle synthesis is a relatively new emerging issue concerning the sustainability. This field has received great attention in recent years due to its capability to design alternative, safer, energy efficient, and less toxic routes towards synthesis. These routes have been associated with the rational utilization of various substances in the nanoparticle preparations and synthetic methods, which have been broadly discussed in this tutorial review. This article is not meant to provide an exhaustive overview of green synthesis of nanoparticles, but to present several pivotal aspects of synthesis with environmental concerns, involving the selection and evaluation of nontoxic capping and reducing agents, the choice of innocuous solvents and the development of energy-efficient synthetic methods. PMID:25615873

  14. Altering petrology through microbial dissimilatory phosphite oxidation

    Science.gov (United States)

    Zhu, H.; Figueroa, I.; Coates, J. D.

    2013-12-01

    Microbial enhanced oil recovery (MEOR) takes advantage of various microbial metabolisms to increase hydrocarbon and energy yield by improving oil flow and flood water sweep in a reservoir during tertiary recovery. Wormholing at the injection well is believed to be the result of the large drop in pressure when water exits the injection well and enters the unconsolidated reservoir matrix. One possible means of prevent this event is to consolidate the rock matrix immediately around the injection well to create a permeable zone of stable petrology. Many microbial processes are known to result in the precipitation of ionic components into their environment creating solid-phase minerals. Such processes could be judiciously applied to bind unconsolidated matrices in order to form a permeable concreted rock matrix, which would minimize wormholing events and thus improve floodwater sweep. However, to date, apart from the application of urea oxidation creating calcium carbonate precipitation, there has been little investigation of the applicability of these precipitated bioconcretions to MEOR strategies and none to control wormholing events. Here we present a novel approach to altering rock petrology to concrete unconsolidated matrices in the near well environment by the biogenesis of authigenic minerals through microbial dissimilatory phosphite oxidation. Desulfotignum phosphitoxidans, strain FiPS-3 is currently the only isolated organism capable of using phosphite (HPO32-) as an electron donor for growth. This process, known as dissimilatory phosphite oxidation (DPO), can be coupled to either sulfate reduction or homoacetogenesis and leads to the accumulation of inorganic phosphate in the medium. The resulting insoluble mineral phases can coat the rock environment resulting in a concretion binding the unconsolidated matrix particles into a single phase. In this study we demonstrate that DPO can effectively produce calcium or magnesium phosphate minerals in packed glass

  15. STRUCTURAL ALTERATIONS OF SKELETAL MUSCLE IN COPD

    Directory of Open Access Journals (Sweden)

    Sunita eMathur

    2014-03-01

    Full Text Available Background: Chronic obstructive pulmonary disease (COPD is a respiratory disease associated with a systemic inflammatory response. Peripheral muscle dysfunction has been well characterized in individuals with COPD and results from a complex interaction between systemic and local factors. Objective: In this narrative review, we will describe muscle wasting in people with COPD, the associated structural changes, muscle regenerative capacity and possible mechanisms for muscle wasting. We will also discuss how structural changes relate to impaired muscle function and mobility in people with COPD. Key Observations: Approximately 30-40% of individuals with COPD experience muscle mass depletion. Furthermore, muscle atrophy is a predictor of physical function and mortality in this population. Associated structural changes include a decreased proportion and size of type-I fibers, reduced oxidative capacity and mitochondrial density mainly in the quadriceps. Observations related to impaired muscle regenerative capacity in individuals with COPD include a lower proportion of central nuclei in the presence or absence of muscle atrophy and decreased maximal telomere length, which has been correlated with reduced muscle cross-sectional area. Potential mechanisms for muscle wasting in COPD may include excessive production of reactive oxygen species, altered amino acid metabolism and lower expression of peroxisome proliferator-activated receptors-gamma-coactivator 1-alpha mRNA. Despite a moderate relationship between muscle atrophy and function, impairments in oxidative metabolism only seems weakly related to muscle function. Conclusion: This review article demonstrates the cellular modifications in the peripheral muscle of people with COPD and describes the evidence of its relationship to muscle function. Future research will focus on rehabilitation strategies to improve muscle wasting and maximize function.

  16. Altered thalamic functional connectivity in multiple sclerosis

    International Nuclear Information System (INIS)

    Highlights: •We demonstrated decreased connectivity between thalamus and cortical regions in MS. •Increased intra- and inter-thalamic connectivity was also observed in MS. •The increased functional connectivity is attenuated by increasing disease duration. -- Abstract: Objective: To compare thalamic functional connectivity (FC) in patients with multiple sclerosis (MS) and healthy controls (HC), and correlate these connectivity measures with other MRI and clinical variables. Methods: We employed resting-state functional MRI (fMRI) to examine changes in thalamic connectivity by comparing thirty-five patients with MS and 35 age- and sex-matched HC. Thalamic FC was investigated by correlating low frequency fMRI signal fluctuations in thalamic voxels with voxels in all other brain regions. Additionally thalamic volume fraction (TF), T2 lesion volume (T2LV), EDSS and disease duration were recorded and correlated with the FC changes. Results: MS patients were found to have a significantly lower TF than HC in bilateral thalami. Compared to HC, the MS group showed significantly decreased FC between thalamus and several brain regions including right middle frontal and parahippocampal gyri, and the left inferior parietal lobule. Increased intra- and inter-thalamic FC was observed in the MS group compared to HC. These FC alterations were not correlated with T2LV, thalamic volume or lesions. In the MS group, however, there was a negative correlation between disease duration and inter-thalamic connectivity (r = −0.59, p < 0.001). Conclusion: We demonstrated decreased FC between thalamus and several cortical regions, while increased intra- and inter-thalamic connectivity in MS patients. These complex functional changes reflect impairments and/or adaptations that are independent of T2LV, thalamic volume or presence of thalamic lesions. The negative correlation between disease duration and inter-thalamic connectivity could indicate an adaptive role of thalamus that is

  17. Altered levels of acetylcholinesterase in Alzheimer plasma.

    Directory of Open Access Journals (Sweden)

    María-Salud García-Ayllón

    Full Text Available BACKGROUND: Many studies have been conducted in an extensive effort to identify alterations in blood cholinesterase levels as a consequence of disease, including the analysis of acetylcholinesterase (AChE in plasma. Conventional assays using selective cholinesterase inhibitors have not been particularly successful as excess amounts of butyrylcholinesterase (BuChE pose a major problem. PRINCIPAL FINDINGS: Here we have estimated the levels of AChE activity in human plasma by first immunoprecipitating BuChE and measuring AChE activity in the immunodepleted plasma. Human plasma AChE activity levels were approximately 20 nmol/min/mL, about 160 times lower than BuChE. The majority of AChE species are the light G(1+G(2 forms and not G(4 tetramers. The levels and pattern of the molecular forms are similar to that observed in individuals with silent BuChE. We have also compared plasma AChE with the enzyme pattern obtained from human liver, red blood cells, cerebrospinal fluid (CSF and brain, by sedimentation analysis, Western blotting and lectin-binding analysis. Finally, a selective increase of AChE activity was detected in plasma from Alzheimer's disease (AD patients compared to age and gender-matched controls. This increase correlates with an increase in the G(1+G(2 forms, the subset of AChE species which are increased in Alzheimer's brain. Western blot analysis demonstrated that a 78 kDa immunoreactive AChE protein band was also increased in Alzheimer's plasma, attributed in part to AChE-T subunits common in brain and CSF. CONCLUSION: Plasma AChE might have potential as an indicator of disease progress and prognosis in AD and warrants further investigation.

  18. Polarization Altering Devices in Guided Wave Optics

    Science.gov (United States)

    Sletten, Mark Arthur

    In this thesis, four guided wave optical devices are investigated, each of which alters the state of polarization of the lightwave which passes through it. Chapter 1 contains general information on the operation of these devices and on the systems in which they are typically used, and the subsequent chapters discuss each device in detail. Chapter 2 presents a quasi-optic analysis of a thin film polarization converter formed by a thin, isotropic film on an anisotropic, electrooptic substrate. In Chapter 3, a singular perturbation technique with multiple scales is used to analyze a thick metal surface polariton polarizer for a planar optical waveguide. This analysis is extended in Chapter 4 to a similar device in which the metal is assumed to have a finite thickness. The analysis indicates two regions of operation for this device and also indicates the importance of phase matching the surface polariton to the transverse magnetic mode guided by the dielectric waveguide. An experimental investigation of a surface polariton polarizer fabricated with optical fiber and silicon v-grooves is reported in Chapter 5. The fabrication process for these devices is described, and the results of investigations into the dependence of the extinction ratio on the device length and fiber core to metal spacing are presented. Chapter 6 outlines a singular perturbation analysis of a polarization splitting directional coupler. Like the polarizers discussed in Chapters 3, 4 and 5, the coupler owes its polarization selecting capability to interactions with surface polaritons. The final chapter contains suggestions for future research related to the polarizer analysis and experiments.

  19. Deforestation alters rainfall: a myth or reality

    Science.gov (United States)

    Hanif, M. F.; Mustafa, M. R.; Hashim, A. M.; Yusof, K. W.

    2016-06-01

    To cope with the issue of food safety and human shelter, natural landscape has gone through a number of alterations. In the coming future, the expansion of urban land and agricultural farms will likely disrupt the natural environment. Researchers have claimed that land use change may become the most serious issue of the current century. Thus, it is necessary to understand the consequences of land use change on the climatic variables, e.g., rainfall. This study investigated the impact of deforestation on local rainfall. An integrated methodology was adopted to achieve the objectives. Above ground biomass was considered as the indicator of forest areas. Time series data of a Moderate Resolution Imaging Spectroradiometer (MODIS) sensor were obtained for the year of 2000, 2005, and 2010. Rainfall data were collected from the Department of Irrigation and Drainage, Malaysia. The MODIS time series data were classified and four major classes were developed based on the Normalised Difference Vegetation Index (NDVI) ranges. The results of the classification showed that water, and urban and agricultural lands have increased in their area by 2, 3, and 6%, respectively. On the other hand, the area of forest has decreased 10% collectively from 2000 to 2010. The results of NDVI and rainfall data were analysed by using a linear regression analysis. The results showed a significant relationship at a 90% confidence interval between rainfall and deforestation (t = 1.92, p = 0.06). The results of this study may provide information about the consequences of land use on the climate on the local scale.

  20. Altered thalamic functional connectivity in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yaou; Liang, Peipeng; Duan, Yunyun; Huang, Jing; Ren, Zhuoqiong; Jia, Xiuqin [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Dong, Huiqing; Ye, Jing [Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Shi, Fu-Dong [Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052 (China); Butzkueven, Helmut [Department of Medicine, University of Melbourne, Parkville 3010 (Australia); Li, Kuncheng, E-mail: kunchengli55@gmail.com [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China)

    2015-04-15

    Highlights: •We demonstrated decreased connectivity between thalamus and cortical regions in MS. •Increased intra- and inter-thalamic connectivity was also observed in MS. •The increased functional connectivity is attenuated by increasing disease duration. -- Abstract: Objective: To compare thalamic functional connectivity (FC) in patients with multiple sclerosis (MS) and healthy controls (HC), and correlate these connectivity measures with other MRI and clinical variables. Methods: We employed resting-state functional MRI (fMRI) to examine changes in thalamic connectivity by comparing thirty-five patients with MS and 35 age- and sex-matched HC. Thalamic FC was investigated by correlating low frequency fMRI signal fluctuations in thalamic voxels with voxels in all other brain regions. Additionally thalamic volume fraction (TF), T2 lesion volume (T2LV), EDSS and disease duration were recorded and correlated with the FC changes. Results: MS patients were found to have a significantly lower TF than HC in bilateral thalami. Compared to HC, the MS group showed significantly decreased FC between thalamus and several brain regions including right middle frontal and parahippocampal gyri, and the left inferior parietal lobule. Increased intra- and inter-thalamic FC was observed in the MS group compared to HC. These FC alterations were not correlated with T2LV, thalamic volume or lesions. In the MS group, however, there was a negative correlation between disease duration and inter-thalamic connectivity (r = −0.59, p < 0.001). Conclusion: We demonstrated decreased FC between thalamus and several cortical regions, while increased intra- and inter-thalamic connectivity in MS patients. These complex functional changes reflect impairments and/or adaptations that are independent of T2LV, thalamic volume or presence of thalamic lesions. The negative correlation between disease duration and inter-thalamic connectivity could indicate an adaptive role of thalamus that is

  1. Algal toxins alter copepod feeding behavior.

    Directory of Open Access Journals (Sweden)

    Jiarong Hong

    Full Text Available Using digital holographic cinematography, we quantify and compare the feeding behavior of free-swimming copepods, Acartia tonsa, on nutritional prey (Storeatula major to that occurring during exposure to toxic and non-toxic strains of Karenia brevis and Karlodinium veneficum. These two harmful algal species produce polyketide toxins with different modes of action and potency. We distinguish between two different beating modes of the copepod's feeding appendages-a "sampling beating" that has short durations (<100 ms and involves little fluid entrainment and a longer duration "grazing beating" that persists up to 1200 ms and generates feeding currents. The durations of both beating modes have log-normal distributions. Without prey, A. tonsa only samples the environment at low frequency. Upon introduction of non-toxic food, it increases its sampling time moderately and the grazing period substantially. On mono algal diets for either of the toxic dinoflagellates, sampling time fraction is high but the grazing is very limited. A. tonsa demonstrates aversion to both toxic algal species. In mixtures of S. major and the neurotoxin producing K. brevis, sampling and grazing diminish rapidly, presumably due to neurological effects of consuming brevetoxins while trying to feed on S. major. In contrast, on mixtures of cytotoxin producing K. veneficum, both behavioral modes persist, indicating that intake of karlotoxins does not immediately inhibit the copepod's grazing behavior. These findings add critical insight into how these algal toxins may influence the copepod's feeding behavior, and suggest how some harmful algal species may alter top-down control exerted by grazers like copepods.

  2. Algal toxins alter copepod feeding behavior.

    Science.gov (United States)

    Hong, Jiarong; Talapatra, Siddharth; Katz, Joseph; Tester, Patricia A; Waggett, Rebecca J; Place, Allen R

    2012-01-01

    Using digital holographic cinematography, we quantify and compare the feeding behavior of free-swimming copepods, Acartia tonsa, on nutritional prey (Storeatula major) to that occurring during exposure to toxic and non-toxic strains of Karenia brevis and Karlodinium veneficum. These two harmful algal species produce polyketide toxins with different modes of action and potency. We distinguish between two different beating modes of the copepod's feeding appendages-a "sampling beating" that has short durations (<100 ms) and involves little fluid entrainment and a longer duration "grazing beating" that persists up to 1200 ms and generates feeding currents. The durations of both beating modes have log-normal distributions. Without prey, A. tonsa only samples the environment at low frequency. Upon introduction of non-toxic food, it increases its sampling time moderately and the grazing period substantially. On mono algal diets for either of the toxic dinoflagellates, sampling time fraction is high but the grazing is very limited. A. tonsa demonstrates aversion to both toxic algal species. In mixtures of S. major and the neurotoxin producing K. brevis, sampling and grazing diminish rapidly, presumably due to neurological effects of consuming brevetoxins while trying to feed on S. major. In contrast, on mixtures of cytotoxin producing K. veneficum, both behavioral modes persist, indicating that intake of karlotoxins does not immediately inhibit the copepod's grazing behavior. These findings add critical insight into how these algal toxins may influence the copepod's feeding behavior, and suggest how some harmful algal species may alter top-down control exerted by grazers like copepods. PMID:22629336

  3. Diastereoselective Total Synthesis of (-)-Galiellalactone.

    Science.gov (United States)

    Kim, Taewoo; Han, Young Taek; An, Hongchan; Kim, Kyeojin; Lee, Jeeyeon; Suh, Young-Ger

    2015-12-18

    An enantioselective total synthesis of (-)-galiellalactone has been accomplished. The key features of the synthesis involve the highly stereoselective construction of the cis-trisubstituted cyclopentane intermediate by a Pd(0)-catalyzed cyclization, the stereospecific introduction of an angular hydroxyl group by Riley oxidation, and the efficient construction of the tricyclic system of (-)-galiellalactone via a combination of diastereoselective Hosomi-Sakurai crotylation and ring-closing metathesis (RCM). PMID:26544529

  4. Kojic acid in organic synthesis

    OpenAIRE

    ZIRAK, MARYAM; Eftekhari-Sis, Bagher

    2015-01-01

    The reactions of kojic acid in organic synthesis are reviewed. The aim of this review is to cover the literature up to the end of 2014, showing the distribution of publications involving kojic acid chemistry in the synthesis of various pyrone containing compounds, pyridine and pyridone heterocycles, and also other organic compounds. First, introductory text about the preparation, biological, and industrial applications, and the chemical properties of kojic acid is given. Then its uses in orga...

  5. Diamond Synthesis Employing Nanoparticle Seeds

    Science.gov (United States)

    Uppireddi, Kishore (Inventor); Morell, Gerardo (Inventor); Weiner, Brad R. (Inventor)

    2014-01-01

    Iron nanoparticles were employed to induce the synthesis of diamond on molybdenum, silicon, and quartz substrates. Diamond films were grown using conventional conditions for diamond synthesis by hot filament chemical vapor deposition, except that dispersed iron oxide nanoparticles replaced the seeding. This approach to diamond induction can be combined with dip pen nanolithography for the selective deposition of diamond and diamond patterning while avoiding surface damage associated to diamond-seeding methods.

  6. Synthesis of new xanthene derivatives

    OpenAIRE

    Kotaskova, Michaela

    2012-01-01

    Xanthene dyes, including fluorescein, are a well-known class of fluorescent dyes, which have widespread applications in natural sciences. The synthesis of xanthene derivatives via acid catalyzed condensation of substituted phenols with phthalic anhydride, to afford the asymmetric derivatives, is well established. The high temperature, harsh reaction conditions and often low yields make this method less convenient. The synthesis of xanthene dyes by direct modification of the fluorophore moiety...

  7. Principles of digital image synthesis

    CERN Document Server

    Glassner, Andrew S

    1995-01-01

    Image synthesis, or rendering, is a field of transformation: it changesgeometry and physics into meaningful images. Because the most popularalgorithms frequently change, it is increasingly important for researchersand implementors to have a basic understanding of the principles of imagesynthesis. Focusing on theory, Andrew Glassner provides a comprehensiveexplanation of the three core fields of study that come together to formdigital image synthesis: the human visual system, digital signalprocessing, and the interaction of matter and light. Assuming no more thana basic background in calculus,

  8. Essentials of inorganic materials synthesis

    CERN Document Server

    Rao, C N R

    2015-01-01

    This compact handbook describes all the important methods of synthesis employed today for synthesizing inorganic materials. Some features: Focuses on modern inorganic materials with applications in nanotechnology, energy materials, and sustainability Synthesis is a crucial component of materials science and technology; this book provides a simple introduction as well as an updated description of methods Written in a very simple style, providing references to the literature to get details of the methods of preparation when required

  9. Sickle erythrocytes inhibit human endothelial cell DNA synthesis

    International Nuclear Information System (INIS)

    Patients with sickle cell anemia experience severe vascular occlusive phenomena including acute pain crisis and cerebral infarction. Obstruction occurs at both the microvascular and the arterial level, and the clinical presentation of vascular events is heterogeneous, suggesting a complex etiology. Interaction between sickle erythrocytes and the endothelium may contribute to vascular occlusion due to alteration of endothelial function. To investigate this hypothesis, human vascular endothelial cells were overlaid with sickle or normal erythrocytes and stimulated to synthesize DNA. The erythrocytes were sedimented onto replicate monolayers by centrifugation for 10 minutes at 17 g to insure contact with the endothelial cells. Incorporation of 3H-thymidine into endothelial cell DNA was markedly inhibited during contact with sickle erythrocytes. This inhibitory effect was enhanced more than twofold when autologous sickle plasma was present during endothelial cell labeling. Normal erythrocytes, with or without autologous plasma, had a modest effect on endothelial cell DNA synthesis. When sickle erythrocytes in autologous sickle plasma were applied to endothelial monolayers for 1 minute, 10 minutes, or 1 hour and then removed, subsequent DNA synthesis by the endothelial cells was inhibited by 30% to 40%. Although adherence of sickle erythrocytes to the endothelial monolayers was observed under these experimental conditions, the effect of sickle erythrocytes on endothelial DNA synthesis occurred in the absence of significant adherence. Hence, human endothelial cell DNA synthesis is partially inhibited by contact with sickle erythrocytes. The inhibitory effect of sickle erythrocytes occurs during a brief (1 minute) contact with the endothelial monolayers, and persists for at least 6 hours of 3H-thymidine labeling

  10. Synthesis and characterization of ferromagnetic nanowires

    Science.gov (United States)

    Tsai, Poching

    Ferromagnetic nanocrystals with shape anisotropy have drawn great attention in the past decades because of their unique magnetic properties and for their potential applications in ultra-high-density magnetic recording media, exchange-coupled nanocomposite magnets and related nanodevices. In this thesis, synthesis and characterixation of ferromagnetic CoNi and CoFe nanowires are reported. CoNi nanocrystals with different size, shape and composition were successfully synthesized via a catalyst chemical solution method. It was found out that the structure and morphology can be controlled by altering the NaOH concentration, and the elongation of the nanowires can be adjusted by changing surfactants ratio and catalyst amount. Unlike the CoNi, CoFe nanocrystals were prepared by a non-catalyst chemistry solution method. The particle size and shape are controlled by varying parameters such as solvent amount, surfactant ratio, reducing agent and heating rate. Morphological, structural, and compositional characterizations of the nanoparticles were performed by using Transmission Electron Microscopy (TEM), high resolution TEM (HRTEM), and X-Ray Diffractometer (XRD). Magnetic properties of nanoparticles of different size were studied by Alternating Gradiant Magnetometer (AGM).

  11. Borosilicate nuclear waste glass alteration kinetics theoretical basis for the kinetic law of nuclear glass alteration

    International Nuclear Information System (INIS)

    Work carried out since the early 1980's to predict the long-term behavior of nuclear containment glasses has revealed the inadequacy of existing models, notably in accounting for the fundamental mechanisms involved in some complex systems (e.g. glass-water-clay), inciting us to examine and discuss the theoretical basis for the hypotheses generally assumed in our models. This paper discusses the theoretical basis for the Aagaard-Helgeson law and its application to nuclear glasses. The contribution of other types of kinetic laws is also considered to describe the alteration kinetics of nuclear glasses. (authors)

  12. Physiological alterations in UV-irradiated cells: liquid holding recovery

    International Nuclear Information System (INIS)

    The biochemical and physiological alterations that occur in ultraviolet irradiated cells, during liquid holding have been studied. Incubation in buffer acts not to interfer directly with the mechanic repairs but by promoting metabolic alterations that would block some irreversible and lethal physiological responses. (L.M.J.)

  13. Elk herbivory alters small mammal assemblages in high elevation drainages

    Science.gov (United States)

    Parsons, Elliott W.R.; Maron, John L.; Martin, Thomas E.

    2012-01-01

    Heavy herbivory by ungulates can substantially alter habitat, but the indirect consequences of habitat modification for animal assemblages that rely on that habitat are not well studied. This is a particularly important topic given that climate change can alter plant–herbivore interactions.

  14. 9 CFR 151.5 - Alteration of pedigree certificate.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Alteration of pedigree certificate. 151.5 Section 151.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT... Certification of Purebred Animals § 151.5 Alteration of pedigree certificate. No pedigree certificate which...

  15. 24 CFR 8.23 - Alterations of existing housing facilities.

    Science.gov (United States)

    2010-04-01

    ... (including a public housing project as required by § 8.25(a)(2)) that has 15 or more units and the cost of the alterations is 75 percent or more of the replacement cost of the completed facility, then the... under this paragraph. Alterations to common areas or parts of facilities that affect accessibility...

  16. 14 CFR 21.289 - Major repairs, rebuilding and alteration.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Major repairs, rebuilding and alteration. 21.289 Section 21.289 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... authorization, a manufacturer may— (a) After finding that a major repair or major alteration meets...

  17. MICROSATELLITE ALTERATION AND ITS CHARACTERISTICS IN COLORECTAL CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To determine the role of microsatellite alterations incarcinogenesis of colorectal carcinoma (CRC). Methods: Alterations of 10 microsatellite loci from 5 different chromosomes were detected in 92 colorectal cancers and their paired normal mucosa by PCR, denatured polyacrylamide gel electrophoresis and silver staining. Associations of microsatellite alterations with clinopathologic parameters were statistically clarified.Results: Alterations of microsatellite were classified into microsatellite instability type I, type II and loss of heterozygosity (LOH). The carcinoma with ≥30% loci microsatellite alterations was defined as replication error(RER) positive tumors. Of 92 cases, 14 were RER+. Microsatellite alterations of P53(1) and D18S363 loci (64.29% ) was most commonly identified in the RER+ tumors. RER+ were more commonly seen in poorly differentiated carcinomas and tended to occur in mucoid carcinomas. The type of microsatellite alterations varied in different histological types of CRC. Conclusions: Microsatellite alteration is a common molecular event in CRC. Different microsatellite loci showed various biologic significance. P53(1) and D18S363 should be essentially detected loci that can show the RER status of tumors.

  18. Biogeochemistry of hydrothermally and adjacent non-altered soils

    Science.gov (United States)

    As a field/lab project, students in the Soil Biogeochemistry class of the University of Nevada, Reno described and characterized seven pedons, developed in hydrothermally and adjacent non-hydrothermally altered andesitic parent material near Reno, NV. Hydrothermally altered soils had considerably lo...

  19. Genetic alterations and markers of melanoma

    Directory of Open Access Journals (Sweden)

    N. N. Mazurenko

    2014-01-01

    Full Text Available Melanoma remains the most deadly form of malignant skin disease with high risk of metastases. Metastatic melanoma is prognostic highly unfavorable and resistant to traditional chemotherapy and biologic treatment. There is a great progress in understanding of the molecular mechanisms underlying melanoma initiation and progression. The external (ultraviolet irradiation and internal (genetic factors are involved in melanoma genesis. 5–14 % of melanoma cases occur in familial context due to genetic predisposition risk factors. Among them rare germinal mutations in the cell cycle genes regulators CDKN2A and CDK4 and in the master gene of melanocyte homeostasis MITF, as well as single nucleotide polymorphisms of several low-penetrated genes, namely MC1R, have been identified. The main cell signaling pathways and oncogene driver mutations are involved in melanoma pathogenesis. RAS / RAF / MEK / ERK cascade is hyperactivated in 75 % of cutaneous melanoma cases. Activation of PI3K / AKT / mTOR signaling pathway is important for melanoma progression. Recent studies revealed that melanomas are genetically and phenotypically heterogeneous tumors. Spectrum of chromosomal alterations and activating mutations corresponding to tumor molecular portraits varies in melanomas of different location. Most of cutaneous melanomas contain BRAF (50 % or NRAS (20 % mutations, and NRAS mutations occur on chronically sun-exposed skin. Activating KIT mutations have been reported in approximately 20–30 % of certain subtypes of melanoma, including acral and mucosal, and melanoma that develop on photodamaged skin. Cutaneous metastatic melanoma derive from preexisting nevi in 25 % of cases, molecular mechanisms of nevi malignization are discussed. Deepsequencing approaches of melanoma samples of different melanoma types highlighted new melanoma driver genes, that are damaged due to tumorigenic effects of ultraviolet: PPP6C, RAC1, SNX31, TACC1 and STK19. The

  20. Synthesis of ferroelectric nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Roervik, Per Martin

    2008-12-15

    The increasing miniaturization of electric and mechanical components makes the synthesis and assembly of nanoscale structures an important step in modern technology. Functional materials, such as the ferroelectric perovskites, are vital to the integration and utility value of nanotechnology in the future. In the present work, chemical methods to synthesize one-dimensional (1D) nanostructures of ferroelectric perovskites have been studied. To successfully and controllably make 1D nanostructures by chemical methods it is very important to understand the growth mechanism of these nanostructures, in order to design the structures for use in various applications. For the integration of 1D nanostructures into devices it is also very important to be able to make arrays and large-area designed structures from the building blocks that single nanostructures constitute. As functional materials, it is of course also vital to study the properties of the nanostructures. The characterization of properties of single nanostructures is challenging, but essential to the use of such structures. The aim of this work has been to synthesize high quality single-crystalline 1D nanostructures of ferroelectric perovskites with emphasis on PbTiO3 , to make arrays or hierarchical nanostructures of 1D nanostructures on substrates, to understand the growth mechanisms of the 1D nanostructures, and to investigate the ferroelectric and piezoelectric properties of the 1D nanostructures. In Paper I, a molten salt synthesis route, previously reported to yield BaTiO3 , PbTiO3 and Na2Ti6O13 nanorods, was re-examined in order to elucidate the role of volatile chlorides. A precursor mixture containing barium (or lead) and titanium was annealed in the presence of NaCl at 760 degrees Celsius or 820 degrees Celsius. The main products were respectively isometric nanocrystalline BaTiO3 and PbTiO3. Nanorods were also detected, but electron diffraction revealed that the composition of the nanorods was