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Sample records for cftr depletion results

  1. CFTR depletion results in changes in fatty acid composition and promotes lipogenesis in intestinal Caco 2/15 cells.

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    Geneviève Mailhot

    , LXRalpha, LXRbeta and RXRalpha. CONCLUSIONS/SIGNIFICANCE: Collectively, our results indicate that CFTR depletion may disrupt FA homeostasis in intestinal cells through alterations in FA uptake and transport combined with stimulation of lipogenesis that occurs by an LXR/RXR-independent mechanism. These findings exclude a contributing role of CFTR in CF-associated fat malabsorption.

  2. Involvement of the Cdc42 pathway in CFTR post-translational turnover and in its plasma membrane stability in airway epithelial cells.

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    Romain Ferru-Clément

    Full Text Available Cystic fibrosis transmembrane conductance regulator (CFTR is a chloride channel that is expressed on the apical plasma membrane (PM of epithelial cells. The most common deleterious allele encodes a trafficking-defective mutant protein undergoing endoplasmic reticulum-associated degradation (ERAD and presenting lower PM stability. In this study, we investigated the involvement of the Cdc42 pathway in CFTR turnover and trafficking in a human bronchiolar epithelial cell line (CFBE41o- expressing wild-type CFTR. Cdc42 is a small GTPase of the Rho family that fulfils numerous cell functions, one of which is endocytosis and recycling process via actin cytoskeleton remodelling. When we treated cells with chemical inhibitors such as ML141 against Cdc42 and wiskostatin against the downstream effector N-WASP, we observed that CFTR channel activity was inhibited, in correlation with a decrease in CFTR amount at the cell surface and an increase in dynamin-dependent CFTR endocytosis. Anchoring of CFTR to the cortical cytoskeleton was then presumably impaired by actin disorganization. When we performed siRNA-mediated depletion of Cdc42, actin polymerization was not impacted, but we observed actin-independent consequences upon CFTR. Total and PM CFTR amounts were increased, resulting in greater activation of CFTR. Pulse-chase experiments showed that while CFTR degradation was slowed, CFTR maturation through the Golgi apparatus remained unaffected. In addition, we observed increased stability of CFTR in PM and reduction of its endocytosis. This study highlights the involvement of the Cdc42 pathway at several levels of CFTR biogenesis and trafficking: (i Cdc42 is implicated in the first steps of CFTR biosynthesis and processing; (ii it contributes to the stability of CFTR in PM via its anchoring to cortical actin; (iii it promotes CFTR endocytosis and presumably its sorting toward lysosomal degradation.

  3. Increased efficacy of VX-809 in different cellular systems results from an early stabilization effect of F508del-CFTR.

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    Farinha, Carlos M; Sousa, Marisa; Canato, Sara; Schmidt, André; Uliyakina, Inna; Amaral, Margarida D

    2015-08-01

    Cystic fibrosis (CF), the most common recessive autosomal disease among Caucasians, is caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) protein. The most common mutation, F508del, leads to CFTR impaired plasma membrane trafficking. Therapies modulating CFTR basic defect are emerging, such as VX-809, a corrector of F508del-CFTR traffic which just succeeded in a Phase III clinical trial. We recently showed that VX-809 is additive to two other correctors (VRT-325 and compound 4a). Here, we aimed to determine whether the differential rescuing by these compounds results from cell-specific factors or rather from distinct effects at the early biogenesis and/or processing. The rescuing efficiencies of the above three correctors were first compared in different cellular models (primary respiratory cells, cystic fibrosis bronchial epithelial and baby hamster kidney [BHK] cell lines) by functional approaches: micro-Ussing chamber and iodide efflux. Next, biochemical methods (metabolic labeling, pulse-chase and immunoprecipitation) were used to determine their impact on CFTR biogenesis / processing. Functional analyses revealed that VX-809 has the greatest rescuing efficacy and that the relative efficiencies of the three compounds are essentially maintained in all three cellular models tested. Nevertheless, biochemical data show that VX-809 significantly stabilizes F508del-CFTR immature form, an effect that is not observed for C3 nor C4. VX-809 and C3 also significantly increase accumulation of immature CFTR. Our data suggest that VX-809 increases the stability of F508del-CFTR immature form at an early phase of its biogenesis, thus explaining its increased efficacy when inducing its rescue. PMID:26171232

  4. First functional polymorphism in CFTR promoter that results in decreased transcriptional activity and Sp1/USF binding

    International Nuclear Information System (INIS)

    Growing evidences show that functionally relevant polymorphisms in various promoters alter both transcriptional activity and affinities of existing protein-DNA interactions, and thus influence disease progression in humans. We previously reported the -94G>T CFTR promoter variant in a female CF patient in whom any known disease-causing mutation has been detected. To investigate whether the -94G>T could be a regulatory variant, we have proceeded to in silico analyses and functional studies including EMSA and reporter gene assays. Our data indicate that the promoter variant decreases basal CFTR transcriptional activity in different epithelial cells and alters binding affinities of both Sp1 and USF nuclear proteins to the CFTR promoter. The present report provides evidence for the first functional polymorphism that negatively affects the CFTR transcriptional activity and demonstrates a cooperative role of Sp1 and USF transcription factors in transactivation of the CFTR gene promoter

  5. The ΔF508-CFTR mutation inhibits wild-type CFTR processing and function when co-expressed in human airway epithelia and in mouse nasal mucosa

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    Tucker Torry A

    2012-09-01

    Full Text Available Abstract Background Rescue or correction of CFTR function in native epithelia is the ultimate goal of CF therapeutics development. Wild-type (WT CFTR introduction and replacement is also of particular interest. Such therapies may be complicated by possible CFTR self-assembly into an oligomer or multimer. Results Surprisingly, functional CFTR assays in native airway epithelia showed that the most common CFTR mutant, ΔF508-CFTR (ΔF-CFTR, inhibits WT-CFTR when both forms are co-expressed. To examine more mechanistically, both forms of CFTR were transfected transiently in varying amounts into IB3-1 CF human airway epithelial cells and HEK-293 human embryonic kidney cells null for endogenous CFTR protein expression. Increasing amounts of ΔF-CFTR inhibited WT-CFTR protein processing and function in CF human airway epithelial cells but not in heterologous HEK-293 cells. Stably expressed ΔF-CFTR in clones of the non-CF human airway epithelial cell line, CALU-3, also showed reduction in cAMP-stimulated anion secretion and in WT-CFTR processing. An ultimate test of this dominant negative-like effect of ΔF-CFTR on WT-CFTR was the parallel study of two different CF mouse models: the ΔF-CFTR mouse and the bitransgenic CFTR mouse corrected in the gut but null in the lung and airways. WT/ΔF heterozygotes had an intermediate phenotype with regard to CFTR agonist responses in in vivo nasal potential difference (NPD recordings and in Ussing chamber recordings of short-circuit current (ISC in vitro on primary tracheal epithelial cells isolated from the same mice. In contrast, CFTR bitransgenic +/− heterozygotes had no difference in their responses versus +/+ wild-type mice. Conclusions Taken altogether, these data suggest that ΔF-CFTR and WT-CFTR co-assemble into an oligomeric macromolecular complex in native epithelia and share protein processing machinery and regulation at the level of the endoplasmic reticulum (ER. As a consequence, ΔF-CFTR slows WT-CFTR

  6. CFTR and Wnt/beta-catenin signaling in lung development

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    Love Damon

    2008-07-01

    Full Text Available Abstract Background Cystic fibrosis transmembrane conductance regulator (CFTR was shown previously to modify stretch induced differentiation in the lung. The mechanism for CFTR modulation of lung development was examined by in utero gene transfer of either a sense or antisense construct to alter CFTR expression levels. The BAT-gal transgenic reporter mouse line, expressing β-galactosidase under a canonical Wnt/β-catenin-responsive promoter, was used to assess the relative roles of CFTR, Wnt, and parathyroid hormone-related peptide (PTHrP in lung organogenesis. Adenoviruses containing full-length CFTR, a short anti-sense CFTR gene fragment, or a reporter gene as control were used in an intra-amniotic gene therapy procedure to transiently modify CFTR expression in the fetal lung. Results A direct correlation between CFTR expression levels and PTHrP levels was found. An inverse correlation between CFTR and Wnt signaling activities was demonstrated. Conclusion These data are consistent with CFTR participating in the mechanicosensory process essential to regulate Wnt/β-Catenin signaling required for lung organogenesis.

  7. N-Alpha-Acetyltransferases and Regulation of CFTR Expression.

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    Vetter, Ali J; Karamyshev, Andrey L; Patrick, Anna E; Hudson, Henry; Thomas, Philip J

    2016-01-01

    The majority of cystic fibrosis (CF)-causing mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) lead to the misfolding, mistrafficking, and degradation of the mutant protein. Inhibition of degradation does not effectively increase the amount of trafficking competent CFTR, but typically leads to increased ER retention of misfolded forms. Thus, the initial off pathway steps occur early in the processing of the protein. To identify proteins that interact with these early forms of CFTR, in vitro crosslink experiments identified cotranslational partners of the nascent chain of the severe misfolded mutant, G85E CFTR. The mutant preferentially interacts with a subunit of an N-alpha-acetyltransferase A. Based on recent reports that acetylation of the N-termini of some N-end rule substrates control their ubiquitination and subsequent degradation, a potential role for this modification in regulation of CFTR expression was assessed. Knockdown experiments identified two complexes, which affect G85E CFTR proteins levels, NatA and NatB. Effects of the knockdowns on mRNA levels, translation rates, and degradation rates established that the two complexes regulate G85E CFTR through two separate mechanisms. NatA acts indirectly by regulating transcription levels and NatB acts through a previously identified, but incompletely understood posttranslational mechanism. This regulation did not effect trafficking of G85E CFTR, which remains retained in the ER, nor did it alter the degradation rate of CFTR. A mutation predicted to inhibit N-terminal acetylation of CFTR, Q2P, was without effect, suggesting neither system acts directly on CFTR. These results contradict the prediction that N-terminal acetylation of CFTR determines its fitness as a proteasome substrate, but rather NatB plays a role in the conformational maturation of CFTR in the ER through actions on an unidentified protein. PMID:27182737

  8. Development of CFTR structure

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    AnnaEPatrick

    2012-09-01

    Full Text Available Cystic fibrosis is a lethal genetic disease caused by lack of functional cystic fibrosis transmembrane conductance regulator (CFTR proteins at the apical surface of secretory epithelia. CFTR is a multidomain protein, containing five domains, and its functional structure is attained in a hierarchical folding process. Most CF-causing mutations in CFTR, including the most common mutation, a deletion of phenylalanine at position 508 (ΔF508, are unable to properly fold into this functional native three dimensional structure. Currently, no high resolution structural information about full length CFTR exists. However, insight has been gained through examining homologous ABC transporter structures, molecular modeling, and high resolution structures of individual, isolated CFTR domains. Taken together, these studies indicate that the prevalent ΔF508 mutation disrupts two essential steps during the development of the native structure: folding of the first nucleotide binding domain (NBD1 and its later association with the fourth intracellular loop (ICL4 in the second transmembrane domain (TMD2. Therapeutics to rescue ΔF508 and other mutants in CFTR can be targeted to correct defects that occur during the complex folding process. This article reviews the structural relationships between CFTR and ABC transporters and current knowledge about how CFTR attains its structure--with a focus on how this process is altered by CF-causing mutations in a manner targetable by therapeutics.

  9. Evaluation of CFTR gene mutations in Adana

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    Ozlem Goruroglu Ozturk; Filiz Kibar; Esin Damla Ziyanoglu Karacor; Salih Cetiner; Gulhan Sahin; Akgun Yaman

    2013-01-01

    ABSTRACT Objective: Cystic fibrosis is the most common autosomal recessive inherited disorder seen in the white populations. It develops in result of mutations of cystic fibrosis transmembrane regulator (CFTR) gene. Rate of these mutations vary in different geographical regions. In this study, we aimed to determine the frequency of CFTR gene mutations in Adana. Methods: DNA samples of 63 subjects (21 women, 42 men) who were diagnosed as cystic fibrosis at Balcali Hospital of Cukurova Universi...

  10. Evaluation of CFTR gene mutations in Adana

    OpenAIRE

    Öztürk, Özlem Görüroğlu; Filiz KIBAR; Karaçor, Esin Damla Ziyanoğlu; Çetiner, Salih; Şahin, Gülhan; Yaman, Akgün

    2013-01-01

    ABSTRACT Objective: Cystic fibrosis is the most common autosomal recessive inherited disorder seen in the white populations. It develops in result of mutations of cystic fibrosis transmembrane regulator (CFTR) gene. Rate of these mutations vary in different geographical regions. In this study, we aimed to determine the frequency of CFTR gene mutations in Adana. Methods: DNA samples of 63 subjects (21 women, 42 men) who were diagnosed as cystic fibrosis at Balcalı Hospital of Çukurova Unive...

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

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    Sonawane Nitin D

    2010-05-01

    Full Text Available 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 detection of cholesterol at the plasma membrane is achieved with capillary microelectrodes with a modified platinum coil that accepts covalent attachment of cholesterol oxidase. Modified electrodes absent cholesterol oxidase serves as a baseline control. Cholesterol synthesis is determined by deuterium incorporation into lipids over time. Incorporation into cholesterol specifically is determined by mass spectrometry analysis. All mice used in the study are on a C57Bl/6 background and are between 6 and 8 weeks of age. Results Membrane cholesterol measurements are elevated in both R117H and ΔF508 mouse nasal epithelium compared to age-matched sibling wt controls demonstrating a genotype correlation to membrane cholesterol detection. Expression of wt CFTR in CF epithelial cells reverts membrane cholesterol to WT levels further demonstrating the impact of CFTR on these processes. In wt epithelial cell, the addition of the CFTR inhibitors, Gly H101 or CFTRinh-172, for 24 h surprisingly results in an initial drop in membrane cholesterol measurement followed by a rebound at 72 h suggesting a feedback mechanism may be driving the increase in membrane cholesterol. De novo cholesterol synthesis contributes to membrane cholesterol accessibility. Conclusions The data in this study suggest that CFTR influences cholesterol trafficking to the plasma membrane, which when depleted, leads to an increase in de novo cholesterol synthesis to restore membrane content.

  12. Lumacaftor alone and combined with ivacaftor: preclinical and clinical trial experience of F508del CFTR correction.

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    Brewington, John J; McPhail, Gary L; Clancy, John P

    2016-01-01

    Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator protein (CFTR), leading to significant morbidity and mortality. CFTR is a chloride and bicarbonate channel at the epithelial cell membrane. The most common CFTR mutation is F508del, resulting in minimal CFTR at the plasma membrane. Current disease management is supportive, whereas an ultimate goal is to develop therapies to restore CFTR activity. We summarize experience with lumacaftor, a small molecule that increases F508del-CFTR levels at the plasma membrane. Lumacaftor in combination with ivacaftor, a modulator of CFTR gating defects, improves clinical outcome measures in patients homozygous for the F508del mutation. Lumacaftor represents a significant advancement in the treatment of biochemical abnormalities in CF. Further development of CFTR modulators will improve upon current therapies, although it remains unclear whether this approach will provide therapies for all CFTR mutations. PMID:26581802

  13. Potentiators exert distinct effects on human, murine, and Xenopus CFTR.

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    Cui, Guiying; Khazanov, Netaly; Stauffer, Brandon B; Infield, Daniel T; Imhoff, Barry R; Senderowitz, Hanoch; McCarty, Nael A

    2016-08-01

    VX-770 (Ivacaftor) has been approved for clinical usage in cystic fibrosis patients with several CFTR mutations. Yet the binding site(s) on CFTR for this compound and other small molecule potentiators are unknown. We hypothesize that insight into this question could be gained by comparing the effect of potentiators on CFTR channels from different origins, e.g., human, mouse, and Xenopus (frog). In the present study, we combined this comparative molecular pharmacology approach with that of computer-aided drug discovery to identify and characterize new potentiators of CFTR and to explore possible mechanism of action. Our results demonstrate that 1) VX-770, NPPB, GlyH-101, P1, P2, and P3 all exhibited ortholog-specific behavior in that they potentiated hCFTR, mCFTR, and xCFTR with different efficacies; 2) P1, P2, and P3 potentiated hCFTR in excised macropatches in a manner dependent on the degree of PKA-mediated stimulation; 3) P1 and P2 did not have additive effects, suggesting that these compounds might share binding sites. Also 4) using a pharmacophore modeling approach, we identified three new potentiators (IOWH-032, OSSK-2, and OSSK-3) that have structures similar to GlyH-101 and that also exhibit ortholog-specific potentiation of CFTR. These could potentially serve as lead compounds for development of new drugs for the treatment of cystic fibrosis. The ortholog-specific behavior of these compounds suggest that a comparative pharmacology approach, using cross-ortholog chimeras, may be useful for identification of binding sites on human CFTR. PMID:27288484

  14. Evaluation of CFTR gene mutations in Adana

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    Ozlem Goruroglu Ozturk

    2013-04-01

    Full Text Available ABSTRACT Objective: Cystic fibrosis is the most common autosomal recessive inherited disorder seen in the white populations. It develops in result of mutations of cystic fibrosis transmembrane regulator (CFTR gene. Rate of these mutations vary in different geographical regions. In this study, we aimed to determine the frequency of CFTR gene mutations in Adana. Methods: DNA samples of 63 subjects (21 women, 42 men who were diagnosed as cystic fibrosis at Balcali Hospital of Cukurova University, were studied for 19 different CFTR mutations by the strip assay method which is based on reverse hybridization. Results: In cystic fibrosis diagnosed patients, 19 mutations were observed of which 9 were homozygous and 10 were heterozygous. ∆F508 frequency was found as 11.9%, and rate of homozygous was found as 66.7%. Mutation frequencies of W1282X and N1303K were found as 2.40% and 4.80% respectively and rate of homozygous mutations were 50% for both. I148T mutation frequency was found as 3.20% and all were heterozygous. For the whole 19 mutations, frequency of mutation in 63 subjects was 22.3%. Conclusion: Detection of CFTR gene mutations by the strip assay method by reverse hybridization is an easy, fast and informative method. However, due to improvability of the common mutations in probable cystic fibrosis patients because of heterogenity in this region, it is still a major problem and does not exclude cystic fibrosis diagnosis. But this problematic issue can be overcome by evaluating the whole exons of CFTR mutations by advanced molecular tecniques. Key words: CFTR, cystic fibrosis, molecular diagnosis, reverse hibridisation [Cukurova Med J 2013; 38(2.000: 202-208

  15. Activation of G551D-CFTR by Bicyclooctane Compounds Is cAMP-dependent and Exhibits Low Sensitivity to Thiazolidinone CFTR Inhibitor CFTRinh-172

    Institute of Scientific and Technical Information of China (English)

    WANG Ying; ZHAO Lu; HE Cheng-yan; XU Li-na; YANG Hong

    2005-01-01

    The G551D-CFTR mutation causing cystic fibrosis (CF) results from a missense mutation at codon 551(G551D) in the gene encoding of the cystic fibrosis transmembrane conductance regulator (CFTR). The G551D mutation in CFTR results in a reduced functional channel but G551D-CFTR is appropriately inserted in the apical membrane. In previous studies we discovered a class of high-affinity bicyclooctane (BCO)G551D-CFTR activators(G551DBCOs) with Kd down to 1μmol/L. In this study, we analyzed the pharmacological activation of G551D-CFTR by the G551DBcos by means of short circuit current analysis and cell-based fluorescence quenching assay. The G551DBCOs-induced G551D-CFTR activation is cAMP-dependent and is less sensitive to thiazolidinone CFTR inhibitor CFTRinh-172. These data suggest that (1) the phosphorylation of G551D-CFTR by protein kinase A is required for the activation by G551DBcos; (2) G551DBCos and CFTRinh-172 may act at the same site on the G551D-CFTR molecule.

  16. CFTR: A New Horizon in the Pathomechanism and Treatment of Pancreatitis.

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    Hegyi, Péter; Wilschanski, Michael; Muallem, Shmuel; Lukacs, Gergely L; Sahin-Tóth, Miklós; Uc, Aliye; Gray, Michael A; Rakonczay, Zoltán; Maléth, József

    2016-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) is an ion channel that conducts chloride and bicarbonate ions across epithelial cell membranes. Mutations in the CFTR gene diminish the ion channel function and lead to impaired epithelial fluid transport in multiple organs such as the lung and the pancreas resulting in cystic fibrosis. Heterozygous carriers of CFTR mutations do not develop cystic fibrosis but exhibit increased risk for pancreatitis and associated pancreatic damage characterized by elevated mucus levels, fibrosis, and cyst formation. Importantly, recent studies demonstrated that pancreatitis causing insults, such as alcohol, smoking, or bile acids, strongly inhibit CFTR function. Furthermore, human studies showed reduced levels of CFTR expression and function in all forms of pancreatitis. These findings indicate that impairment of CFTR is critical in the development of pancreatitis; therefore, correcting CFTR function could be the first specific therapy in pancreatitis. In this review, we summarize recent advances in the field and discuss new possibilities for the treatment of pancreatitis. PMID:26856995

  17. Islet-intrinsic effects of CFTR mutation.

    Science.gov (United States)

    Koivula, Fiona N Manderson; McClenaghan, Neville H; Harper, Alan G S; Kelly, Catriona

    2016-07-01

    Cystic fibrosis-related diabetes (CFRD) is the most significant extra-pulmonary comorbidity in cystic fibrosis (CF) patients, and accelerates lung decline. In addition to the traditional view that CFRD is a consequence of fibrotic destruction of the pancreas as a whole, emerging evidence may implicate a role for cystic fibrosis transmembrane-conductance regulator (CFTR) in the regulation of insulin secretion from the pancreatic islet. Impaired first-phase insulin responses and glucose homeostasis have also been reported in CF patients. CFTR expression in both human and mouse beta cells has been confirmed, and recent studies have shown differences in endocrine pancreatic morphology from birth in CF. Recent experimental evidence suggests that functional CFTR channels are required for insulin exocytosis and the regulation of membrane potential in the pancreatic beta cell, which may account for the impairments in insulin secretion observed in many CF patients. These novel insights suggest that the pathogenesis of CFRD is more complicated than originally thought, with implications for diabetes treatment and screening in the CF population. This review summarises recent emerging evidence in support of a primary role for endocrine pancreatic dysfunction in the development of CFRD. Summary • CF is an autosomal recessive disorder caused by mutations in the CFTR gene • The vast majority of morbidity and mortality in CF results from lung disease. However CFRD is the largest extra-pulmonary co-morbidity and rapidly accelerates lung decline • Recent experimental evidence shows that functional CFTR channels are required for normal patterns of first phase insulin secretion from the pancreatic beta cell • Current clinical recommendations suggest that insulin is more effective than oral glucose-lowering drugs for the treatment of CFRD. However, the emergence of CFTR corrector and potentiator drugs may offer a personalised approach to treating diabetes in the CF population

  18. Osteoblast CFTR inactivation reduces differentiation and osteoprotegerin expression in a mouse model of cystic fibrosis-related bone disease.

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    Michael S Stalvey

    signaling was defective in Cftr-/- murine calvarial osteoblasts. These results support that genetic inactivation of CFTR in osteoblasts contributes to low bone mass and that targeting osteoblasts may represent an effective strategy to treat CFBD.

  19. Mechanisms of CFTR functional variants that impair regulated bicarbonate permeation and increase risk for pancreatitis but not for cystic fibrosis.

    OpenAIRE

    Jessica LaRusch; Jinsei Jung; General, Ignacio J.; Lewis, Michele D; Hyun Woo Park; Brand, Randall E.; Andres Gelrud; Anderson, Michelle A.; Banks, Peter A; Darwin Conwell; Christopher Lawrence; Joseph Romagnuolo; John Baillie; Samer Alkaade; Gregory Cote

    2014-01-01

    CFTR is a dynamically regulated anion channel. Intracellular WNK1-SPAK activation causes CFTR to change permeability and conductance characteristics from a chloride-preferring to bicarbonate-preferring channel through unknown mechanisms. Two severe CFTR mutations (CFTRsev ) cause complete loss of CFTR function and result in cystic fibrosis (CF), a severe genetic disorder affecting sweat glands, nasal sinuses, lungs, pancreas, liver, intestines, and male reproductive system. We hypothesize tha...

  20. Early results of studies on the levels of depleted uranium excreted by Balkan residents

    International Nuclear Information System (INIS)

    Urine samples collected from residents of Bosnia and Herzegovina and Kosovo were analysed to determine their natural and depleted uranium content using MC-ICP-MS. All may have been exposed to depleted uranium released as a consequence of the deployment of armour-piercing rounds by the US Air Force. A 236U tracer was employed to determine chemical recovery. Early results suggest that the levels of natural and depleted uranium excretion by the subjects, which ranged in age from 1 to 71 years, ranged from 2.8 - 58.2 ng d-1 and 1.3 - 46.3 ng d-1 , respectively. The results suggest accumulated body burdens of depleted uranium ranging from close to zero to 46 μg. All the body burdens predicted are lower than published values for the uranium content of the body (90μg) and health effects are not predicted. Further studies are underway to check the provenance of the results. (author)

  1. Toxicity of Depleted Uranium Dust Particles: Results of a New Model

    International Nuclear Information System (INIS)

    Depleted uranium (DU) is mostly composed of U-238, a naturally radioactive isotope. Concerning chemical toxicity, uranium, being a heavy metal, is known to have toxic effects on specific organs in the body, the kidneys in particular. Its effects are similar to those of other heavy metals, such as lead and cadmium. Scientific evidence resulting both from in vitro and in vivo analyses shows that current models of the mechanisms of toxicity of uranium dust are not fully satisfactory. They should be refined in order to obtain more effective responses and predictions regarding health effects. In particular, radiotoxicity potential of Depleted Uranium dust originated by military use of this material for ammunition must be re-evaluated taking into account the bystander effect, the dose enhancing effect and other minor phenomena. Uranium dust has both chemical and radiological toxicity: the synergistic aspect of the two effects has to be accounted for, in order to arrive to a complete description of the phenomenon. The combination of the two different toxicities (chemical and radiological) of depleted uranium is attempted here for the first time, approaching the long-term effects of Depleted Uranium, and in particular the carcinogenetic effects. A case study (Balkan war, 1999) is discussed. (Author)

  2. Targeted Correction and Restored Function of the CFTR Gene in Cystic Fibrosis Induced Pluripotent Stem Cells

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    Ana M. Crane

    2015-04-01

    Full Text Available Recently developed reprogramming and genome editing technologies make possible the derivation of corrected patient-specific pluripotent stem cell sources—potentially useful for the development of new therapeutic approaches. Starting with skin fibroblasts from patients diagnosed with cystic fibrosis, we derived and characterized induced pluripotent stem cell (iPSC lines. We then utilized zinc-finger nucleases (ZFNs, designed to target the endogenous CFTR gene, to mediate correction of the inherited genetic mutation in these patient-derived lines via homology-directed repair (HDR. We observed an exquisitely sensitive, homology-dependent preference for targeting one CFTR allele versus the other. The corrected cystic fibrosis iPSCs, when induced to differentiate in vitro, expressed the corrected CFTR gene; importantly, CFTR correction resulted in restored expression of the mature CFTR glycoprotein and restoration of CFTR chloride channel function in iPSC-derived epithelial cells.

  3. Functional interaction between TRP4 and CFTR in mouse aorta endothelial cells

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    Droogmans Guy

    2001-05-01

    Full Text Available Abstract Background This study describes the functional interaction between the putative Ca2+ channel TRP4 and the cystic fibrosis transmembrane conductance regulator, CFTR, in mouse aorta endothelium (MAEC. Results MAEC cells express CFTR transcripts as shown by RT-PCR analysis. Application of a phosphorylating cocktail activated a Cl- current with characteristics similar to those of CFTR mediated currents in other cells types (slow activation by cAMP, absence of rectification, block by glibenclamide. The current is present in trp4 +/+ MAEC, but not in trp4 -/- cells, although the expression of CFTR seems unchanged in the trp4 deficient cells as judged from RT-PCR analysis. Conclusions It is concluded that TRP4 is necessary for CFTR activation in endothelium, possibly by providing a scaffold for the formation of functional CFTR channels.

  4. Duplicated CFTR isoforms in eels diverged in regulatory structures and osmoregulatory functions.

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    Wong, Marty Kwok-Shing; Pipil, Supriya; Kato, Akira; Takei, Yoshio

    2016-09-01

    Two cystic fibrosis transmembrane conductance regulator (CFTR) isoforms, CFTRa and CFTRb, were cloned in Japanese eel and their structures and functions were studied in different osmoregulatory tissues in freshwater (FW) and seawater (SW) eels. Molecular phylogenetic results suggested that the CFTR duplication in eels occurred independently of the duplication event in salmonid. CFTRa was expressed in the intestine and kidney and downregulated in both tissues in SW eels, while CFTRb was specifically expressed in the gill and greatly upregulated in SW eels. Structurally, the CFTR isoforms are similar in most functional domains except the regulatory R domain, where the R domain of CFTRa is similar to that of human CFTR but the R domain of CFTRb is unique in having high intrinsic negative charges and fewer phosphorylation sites, suggesting divergence of isoforms in terms of gating properties and hormonal regulation. Immunohistochemical results showed that CFTR was localized on the apical regions of SW ionocytes, suggesting a Cl(-) secretory role as in other teleosts. In intestine and kidney, however, immunoreactive CFTR was mostly found in the cytosolic vesicles in FW eels, indicating that Cl(-) channel activity could be low at basal conditions, but could be rapidly increased by membrane insertion of the stored channels. Guanylin (GN), a known hormone that increases CFTR activity in mammalian intestine, failed to redistribute CFTR and to affect its expression in eel intestine. The results suggested that GN-independent CFTR regulation is present in eel intestine and kidney. PMID:27322796

  5. Micelle-induced depletion interaction and resultant structure in charged colloidal nanoparticle system

    International Nuclear Information System (INIS)

    The evolution of the interaction and the resultant structure in the mixed system of anionic silica nanoparticles (Ludox LS30) and non-ionic surfactant decaethylene glycol monododecylether (C12E10), undergoing phase separation, have been studied using small-angle neutron scattering and dynamic light scattering. The measurements have been carried out for a fixed concentration of nanoparticle (1 wt. %) with varying concentration of surfactant (0 to 1 wt. %), in the absence and presence of an electrolyte. It is found that the micelles of non-ionic surfactant adsorb on the nanoparticle in the absence of electrolyte (form stable system), whereas these micelles become non-adsorbing in the presence of electrolyte (show phase separation). The phase separation arises because of C12E10 micelles, causing depletion interaction between nanoparticles and leading to their aggregation. The interaction is modeled by double Yukawa potential accounting for attractive depletion as well as repulsive electrostatic forces. Both the interactions (attraction and repulsion) are found to be of long-range. The nanoparticle aggregation (phase separation) is governed by the increase in the magnitude and the range of the depletion attraction with the increase in the surfactant concentration. The nanoparticle aggregates formed are quite large in size (order of micron) and are characterized by the surface fractal having simple cubic packing of nanoparticles within the aggregates

  6. Targeting the Intracellular Environment in Cystic Fibrosis: Restoring Autophagy as a Novel Strategy to Circumvent the CFTR Defect.

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    Villella, Valeria Rachela; Esposito, Speranza; Bruscia, Emanuela M; Maiuri, Maria Chiara; Raia, Valeria; Kroemer, Guido; Maiuri, Luigi

    2013-01-01

    Cystic fibrosis (CF) patients harboring the most common deletion mutation of the CF transmembrane conductance regulator (CFTR), F508del, are poor responders to potentiators of CFTR channel activity which can be used to treat a small subset of CF patients who genetically carry plasma membrane (PM)-resident CFTR mutants. The misfolded F508del-CFTR protein is unstable in the PM even if rescued by pharmacological agents that prevent its intracellular retention and degradation. CF is a conformational disease in which defective CFTR induces an impressive derangement of general proteostasis resulting from disabled autophagy. In this review, we discuss how rescuing Beclin 1 (BECN1), a major player of autophagosome formation, either by means of direct gene transfer or indirectly by administration of proteostasis regulators, could stabilize F508del-CFTR at the PM. We focus on the relationship between the improvement of peripheral proteostasis and CFTR PM stability in F508del-CFTR homozygous bronchial epithelia or mouse lungs. Moreover, this article reviews recent pre-clinical evidence indicating that targeting the intracellular environment surrounding the misfolded mutant CFTR instead of protein itself could constitute an attractive therapeutic option to sensitize patients carrying the F508del-CFTR mutation to the beneficial action of CFTR potentiators on lung inflammation. PMID:23346057

  7. Targeting the intracellular environment in cystic fibrosis: restoring autophagy as a novel strategy to circumvent the CFTR defect

    Directory of Open Access Journals (Sweden)

    Valeria Rachela Villella

    2013-01-01

    Full Text Available Cystic fibrosis (CF patients harboring the most common deletion mutation of the cystic fibrosis transmembrane conductance regulator (CFTR, F508del, are poor responders to potentiators of CFTR channel activity which can be used to treat a small subset of CF patients who genetically carry plasma membrane-resident CFTR mutants. The misfolded F508del-CFTR protein is unstable in the plasma membrane even if rescued by pharmacological agents that prevent its intracellular retention and degradation. CF is a conformational disease in which defective CFTR induces an impressive derangement of general proteostasis resulting from disabled autophagy. In this review, we discuss how rescuing Beclin 1 (BECN1, a major player of autophagosome formation, either by means of direct gene transfer or indirectly by administration of proteostasis regulators, could stabilize F508del-CFTR at the plasma membrane. We focus on the relationship between the improvement of peripheral proteostasis and CFTR plasma membrane stability in F508del-CFTR homozygous bronchial epithelia or mouse lungs. Moreover, this article reviews recent preclinical evidence indicating that targeting the intracellular environment surrounding the misfolded mutant CFTR instead of protein itself could constitute an attractive therapeutic option to sensitize patients carrying the F508del-CFTR mutation to the beneficial action of CFTR potentiators on lung inflammation.

  8. Determination of CFTR densities in erythrocyte plasma membranes using recognition imaging

    Science.gov (United States)

    Ebner, Andreas; Nikova, Dessy; Lange, Tobias; Häberle, Johannes; Falk, Sabine; Dübbers, Angelika; Bruns, Reimer; Hinterdorfer, Peter; Oberleithner, Hans; Schillers, Hermann

    2008-09-01

    CFTR (cystic fibrosis transmembrane conductance regulator) is a cAMP-regulated chloride (Cl-) channel that plays an important role in salt and fluid movement across epithelia. Cystic fibrosis (CF), the most common genetic disease among Caucasians, is caused by mutations in the gene encoding CFTR. The most predominant mutation, F508del, disturbs CFTR protein trafficking, resulting in a reduced number of CFTR in the plasma membrane. Recent studies indicate that CFTR is not only found in epithelia but also in human erythrocytes. Although considerable attempts have been made to quantify CFTR in cells, conclusions on numbers of CFTR molecules localized in the plasma membrane have been drawn indirectly. AFM has the power to provide the needed information, since both sub-molecular spatial resolution and direct protein recognition via antibody-antigen interaction can be observed. We performed a quantification study of the CFTR copies in erythrocyte membranes at the single molecule level, and compared the difference between healthy donors and CF patients. We detected that the number of CFTR molecules is reduced by 70% in erythrocytes of cystic fibrosis patients.

  9. Targeting F508del-CFTR to develop rational new therapies for cystic fibrosis

    Institute of Scientific and Technical Information of China (English)

    Zhi-wei CAI; Jia LIU; Hong-yu LI; David N SHEPPARD

    2011-01-01

    The mutation F508del is the commonest cause of the genetic disease cystic fibrosis (CF). CF disrupts the function of many organs in the body, most notably the lungs, by perturbing salt and water transport across epithelial surfaces. F508del causes harm in two principal ways. First,the mutation prevents delivery of the cystic fibrosis transmembrane conductance regulator (CFTR) to its correct cellular location,the apical(lumen-facing) membrane of epithelial cells. Second, F508del perturbs the Cl- channel function of CFTR by disrupting channel gating. Here, we discuss the development of rational new therapies for CF that target F508del-CFTR.We highlight how structural studies provide new insight into the role of F508 in the regulation of channel gating by cycles of ATP binding and hydrolysis. We emphasize the use of high-throughput screening to identify lead compounds for therapy development.These compounds include CFTR correctors that restore the expression of F508del-CFTR at the apical membrane of epithelial cells and CFTR potentiators that rescue the F508del-CFTR gating defect. Initial results from clinical trials of CFTR correctors and potentiators augur well for the development of small molecule therapies that target the root cause of CF: mutations in CFTR.

  10. Determination of CFTR densities in erythrocyte plasma membranes using recognition imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ebner, Andreas; Hinterdorfer, Peter [Institute for Biophysics, University of Linz, A-4040 Linz (Austria); Nikova, Dessy; Lange, Tobias; Bruns, Reimer; Oberleithner, Hans; Schillers, Hermann [Institute of Physiology II, University of Muenster, D-48149 Muenster (Germany); Haeberle, Johannes; Falk, Sabine; Duebbers, Angelika [Department of Pediatrics, University Hospitals of Muenster, D-48149 Muenster (Germany)], E-mail: schille@uni-muenster.de

    2008-09-24

    CFTR (cystic fibrosis transmembrane conductance regulator) is a cAMP-regulated chloride (Cl{sup -}) channel that plays an important role in salt and fluid movement across epithelia. Cystic fibrosis (CF), the most common genetic disease among Caucasians, is caused by mutations in the gene encoding CFTR. The most predominant mutation, F508del, disturbs CFTR protein trafficking, resulting in a reduced number of CFTR in the plasma membrane. Recent studies indicate that CFTR is not only found in epithelia but also in human erythrocytes. Although considerable attempts have been made to quantify CFTR in cells, conclusions on numbers of CFTR molecules localized in the plasma membrane have been drawn indirectly. AFM has the power to provide the needed information, since both sub-molecular spatial resolution and direct protein recognition via antibody-antigen interaction can be observed. We performed a quantification study of the CFTR copies in erythrocyte membranes at the single molecule level, and compared the difference between healthy donors and CF patients. We detected that the number of CFTR molecules is reduced by 70% in erythrocytes of cystic fibrosis patients.

  11. SNaPshot assay for the detection of the most common CFTR mutations in infertile men.

    Directory of Open Access Journals (Sweden)

    Predrag Noveski

    Full Text Available Congenital bilateral absence of vas deferens (CBAVD is the most common CFTR-related disorder (CFTR-RD that explains about 1-2% of the male infertility cases. Controversial data have been published regarding the involvement of CFTR mutations in infertile men with non-obstructive azoospermia and oligozoospermia. Here, we describe single base extension (SNaPshot assay for detection of 11 common CFTR mutations: F508del, G542X, N1303K, 621+1G->T, G551D, R553X, R1162X, W1282X, R117H, 2184insA and 1717-1G->A and IVS8polyT variants. The assay was validated on 50 previously genotyped samples and was used to screen a total of 369 infertile men with different impairment of spermatogenesis and 136 fertile controls. Our results show that double heterozygosity of cystic fibrosis (CF and CFTR-related disorder (CFTR-RD mutations are found in a high percentage (22.7% of infertile men with obstructive azoospermia, but not in other studied groups of infertile men. The SNaPshot assay described here is an inexpensive, fast and robust method for primary screening of the most common CFTR mutations both in patients with classical CF and CFTR-RD. It can contribute to better understanding of the role of CFTR mutations in impaired spermatogenesis, ultimately leading to improved management of infertile men.

  12. RNA interference for CFTR attenuates lung fluid absorption at birth in rats

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    Folkesson Hans G

    2008-07-01

    Full Text Available Abstract Background Small interfering RNA (siRNA against αENaC (α-subunit of the epithelial Na channel and CFTR (cystic fibrosis transmembrane conductance regulator was used to explore ENaC and CTFR function in newborn rat lungs. Methods Twenty-four hours after trans-thoracic intrapulmonary (ttip injection of siRNA-generating plasmid DNA (pSi-0, pSi-4, or pSi-C2, we measured CFTR and ENaC expression, extravascular lung water, and mortality. Results αENaC and CFTR mRNA and protein decreased by ~80% and ~85%, respectively, following αENaC and CFTR silencing. Extravascular lung water and mortality increased after αENaC and CFTR-silencing. In pSi-C2-transfected isolated DLE cells there were attenuated CFTR mRNA and protein. In pSi-4-transfected DLE cells αENaC mRNA and protein were both reduced. Interestingly, CFTR-silencing also reduced αENaC mRNA and protein. αENaC silencing, on the other hand, only slightly reduced CFTR mRNA and protein. Conclusion Thus, ENaC and CFTR are both involved in the fluid secretion to absorption conversion around at birth.

  13. CFTR activity and mitochondrial function

    OpenAIRE

    Angel Gabriel Valdivieso; Santa-Coloma, Tomás A.

    2013-01-01

    Cystic Fibrosis (CF) is a frequent and lethal autosomal recessive disease, caused by mutations in the gene encoding the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). Before the discovery of the CFTR gene, several hypotheses attempted to explain the etiology of this disease, including the possible role of a chloride channel, diverse alterations in mitochondrial functions, the overexpression of the lysosomal enzyme α-glucosidase and a deficiency in the cytosolic enzyme glucose 6-p...

  14. Contamination with radionuclides and depleted uranium as a result of NATO aggression against Yugoslavia

    International Nuclear Information System (INIS)

    It appears that the amount of depleted uranium (DU) is approaching 106 tons at world level. Depleted uranium is a by-product in uranium enrichment process. As such, and at the same time being low radioactive, DU has legal status of low-level radioactive waste. On the other hand, DU is natural present in nature. This is the reason why many claim that it cannot produce major damage if discharged in the environment and that it can be used for ammunition construction material. To regret, DU due to its remarkable physical and mechanical properties has been widely used for the military purposes only. Nowadays many armies have it as a part of standard ammunition stock. To much less extend, it has been used as a shield for various types of armored vehicles. So far, DU has been extensively used on a large scale at several locations on the globe. The most important ones are the test area in Mohave Desert, USA, Gulf War, Iraq, Bosnia and Herzegovina and most recently NATO aggression on Yugoslavia. As a result of extensive DU use, there are many pro and contras regarding DU harmful effects on the environment and life in general. On the subject expert opinion strongly disagree, while public opinion is very much against its use, in particular for military purpose.From the existing experience on the DU impact on the life and environment it is evident that DU can create harmful effects. So far, humans were of prime importance and most of the observations, results and discussions refer to humans, but also there is a growing concern for the biota in general. This paper summarizes some of the known facts regarding depleted uranium, its use as a material for ammunition manufacturing and possible harmful affects in connection with it. Paper also suggests some of the measures that could be considered to follow and remedy the current DU contamination of Kosovo and Metohija, and some other spots in FR Yugoslavia. (author)

  15. Characterization of a critical role for CFTR chloride channels in cardioprotection against ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Sunny Yang XIANG; Linda L YE; LI-lu Marie DUAN; Li-hui LIU; Zhi-dong GE; John A AUCHAMPACH; Garrett J GROSS; Dayue Darrel DUAN

    2011-01-01

    Aim: To further characterize the functional role of cystic fibrosis transmembrane conductance regulator (CFTR) in early and late (second window) ischemic preconditioning (IPC)- and postcondtioning (POC)-mediated cardioprotection against ischemia/reperfusion (I/R) injury.Methods: CFTR knockout (CFTR-/-) mice and age- and gender-matched wild-type (CFTR+/+) and heterozygous (CFTR+/-) mice were used.In in vivo studies, the animals were subjected to a 30-min coronary occlusion followed by a 40-min reperfusion. In ex vivo (isolate heart) studies, a 45-min global ischemia was applied. To evaluate apoptosis, the level of activated caspase 3 and TdT-mediated dUTP-X nick end labeling (TUNEL) were examined.Results: In the in vivo I/R models, early IPC significantly reduced the myocardial infarct size in wild-type (CFTR+/+) (from 40.4%±5.3% to 10.4%±2.0%, n=8, P<0.001) and heterozygous (CFTR+/-) littermates (from 39.4%±2.4% to 15.4%±5.1%, n=6, P<0.001) but failed to protect CFTR knockout (CFTR-/-) mice from I/R induced myocardial infarction (46.9%±6.2% vs 55.5%±7.8%, n=6, P>0.5). Similar results were observed in the in vivo late IPC experiments. Furthermore, in both in vivo and ex vivo I/R models, POC significantly reduced myocardial infarction in wild-type mice, but not in CFTR knockout mice. In ex vivo I/R models, targeted inactivation of CFTRgene abolished the protective effects of IPC against I/R-induced apoptosis.Conclusion: These results provide compelling evidence for a critical role for CFTR Cl- channels in IPC- and POC-mediated cardioprotection against I/R-induced myocardial injury.

  16. The "Goldilocks Effect" in Cystic Fibrosis: identification of a lung phenotype in the cftr knockout and heterozygous mouse

    Directory of Open Access Journals (Sweden)

    Bates Jason HT

    2004-07-01

    Full Text Available Abstract Background Cystic Fibrosis is a pleiotropic disease in humans with primary morbidity and mortality associated with a lung disease phenotype. However, knockout in the mouse of cftr, the gene whose mutant alleles are responsible for cystic fibrosis, has previously failed to produce a readily, quantifiable lung phenotype. Results Using measurements of pulmonary mechanics, a definitive lung phenotype was demonstrated in the cftr-/- mouse. Lungs showed decreased compliance and increased airway resistance in young animals as compared to cftr+/+ littermates. These changes were noted in animals less than 60 days old, prior to any long term inflammatory effects that might occur, and are consistent with structural differences in the cftr-/- lungs. Surprisingly, the cftr+/- animals exhibited a lung phenotype distinct from either the homozygous normal or knockout genotypes. The heterozygous mice showed increased lung compliance and decreased airway resistance when compared to either homozygous phenotype, suggesting a heterozygous advantage that might explain the high frequency of this mutation in certain populations. Conclusions In the mouse the gene dosage of cftr results in distinct differences in pulmonary mechanics of the adult. Distinct phenotypes were demonstrated in each genotype, cftr-/-, cftr +/-, and cftr+/+. These results are consistent with a developmental role for CFTR in the lung.

  17. Solar Wind Effects on Plasma Density Depletions: C/NOFS Results with Related Observations from DMSP

    Science.gov (United States)

    Burke, W. J.; Gentile, L. C.; Roddy, P. A.; Retterer, J. M.; Wilson, G. R.; de La Beaujardiere, O.; Su, Y.

    2010-12-01

    Before C/NOFS, the prevailing wisdom was that equatorial plasma bubbles (EPBs) were primarily a post-sunset phenomenon. Changes in the ionosphere after sunset create conditions favorable for instability formation as polarization electric fields increase near the terminator. Plasma irregularities that develop in the bottomside of the F-layer grow into large depletions that rise rapidly into the topside ionosphere. By two hours in local time after sunset the initial upward drift of the ionosphere reverses suppressing further development of instabilities. Tsunoda’s [1985] seasonal-longitudinal model predicted that EPB rates should peak near times when the equatorial declination and the dusk terminator are closely aligned. Under these conditions E-layer conductance vanishes at both ends of flux tubes simultaneously, allowing EPBs to grow most rapidly. We validated this model during the recent solar maximum. In this unusual solar minimum, however, C/NOFS has encountered very few post-sunset depletions. They commonly appear between local midnight and dawn. We trace the energy flow from the Sun to the Earth to demonstrate that C/NOFS measurements are providing key insights into the dynamics of the Ionosphere-Thermosphere system. Results suggest that systematic effects of solar wind / IMF on dynamics of equatorial plasmas and electric fields may allow long-term alerts about impending ionospheric disturbances that lead to scintillation activity. Reference: Tsunoda, R. T. (1985), J. Geophys. Res., 90, 447.

  18. Transient Treg-cell depletion in adult mice results in persistent self-reactive CD4(+) T-cell responses.

    Science.gov (United States)

    Nyström, Sofia N; Bourges, Dorothée; Garry, Sarah; Ross, Ellen M; van Driel, Ian R; Gleeson, Paul A

    2014-12-01

    Depletion of Foxp3(+) CD4(+) regulatory T cells (Treg) in adults results in chronic inflammation and autoimmune disease. However, the impact of transient Treg-cell depletion on self-reactive responses is poorly defined. Here, we studied the effect of transient depletion of Treg cells on CD4(+) T-cell responses to endogenous self-antigens. Short-term ablation of Treg cells in mice resulted in rapid activation of CD4(+) T cells, increased percentage of IFN-γ(+) and Th17 cells in lymphoid organs, and development of autoimmune gastritis. To track self-reactive responses, we analyzed the activation of naïve gastric-specific CD4(+) T cells. There was a dramatic increase in proliferation and acquisition of effector function of gastric-specific T cells in the stomach draining LNs of Treg-cell-depleted mice, compared with untreated mice, either during Treg-cell depletion or after Treg-cell reconstitution. Moreover, the hyperproliferation of gastric-specific T cells in the Treg-cell-ablated mice was predominantly antigen-dependent. Transient depletion of Treg cells resulted in a shift in the ratio of peripheral:thymic Treg cells in the reemerged Treg-cell population, indicating an altered composition of Treg cells. These findings indicate that transient Treg-cell depletion results in ongoing antigen-driven self-reactive T-cell responses and emphasize the continual requirement for an intact Treg-cell population. PMID:25231532

  19. The Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Uses its C-Terminus to Regulate the A2B Adenosine Receptor.

    Science.gov (United States)

    Watson, Michael J; Lee, Shernita L; Marklew, Abigail J; Gilmore, Rodney C; Gentzsch, Martina; Sassano, Maria F; Gray, Michael A; Tarran, Robert

    2016-01-01

    CFTR is an apical membrane anion channel that regulates fluid homeostasis in many organs including the airways, colon, pancreas and sweat glands. In cystic fibrosis, CFTR dysfunction causes significant morbidity/mortality. Whilst CFTR's function as an ion channel has been well described, its ability to regulate other proteins is less understood. We have previously shown that plasma membrane CFTR increases the surface density of the adenosine 2B receptor (A2BR), but not of the β2 adrenergic receptor (β2AR), leading to an enhanced, adenosine-induced cAMP response in the presence of CFTR. In this study, we have found that the C-terminal PDZ-domain of both A2BR and CFTR were crucial for this interaction, and that replacing the C-terminus of A2BR with that of β2AR removed this CFTR-dependency. This observation extended to intact epithelia and disruption of the actin cytoskeleton prevented A2BR-induced but not β2AR-induced airway surface liquid (ASL) secretion. We also found that CFTR expression altered the organization of the actin cytoskeleton and PDZ-binding proteins in both HEK293T cells and in well-differentiated human bronchial epithelia. Furthermore, removal of CFTR's PDZ binding motif (ΔTRL) prevented actin rearrangement, suggesting that CFTR insertion in the plasma membrane results in local reorganization of actin, PDZ binding proteins and certain GPCRs. PMID:27278076

  20. Tgf-β1 inhibits Cftr biogenesis and prevents functional rescue of ΔF508-Cftr in primary differentiated human bronchial epithelial cells.

    Directory of Open Access Journals (Sweden)

    Steven M Snodgrass

    Full Text Available CFTR is an integral transmembrane glycoprotein and a cAMP-activated Cl(- channel. Mutations in the CFTR gene lead to Cystic Fibrosis (CF-an autosomal recessive disease with majority of the morbidity and mortality resulting from airway infection, inflammation, and fibrosis. The most common disease-associated mutation in the CFTR gene-deletion of Phe508 (ΔF508 leads to a biosynthetic processing defect of CFTR. Correction of the defect and delivery of ΔF508-CFTR to the cell surface has been highly anticipated as a disease modifying therapy. Compared to promising results in cultured cell this approach was much less effective in CF patients in an early clinical trial. Although the cause of failure to rescue ΔF508-CFTR in the clinical trial has not been determined, presence of factor(s that interfere with the rescue in vivo could be considered. The cytokine TGF-β1 is frequently elevated in CF patients. TGF-β1 has pleiotropic effects in different disease models and genetic backgrounds and little is known about TGF-β1 effects on CFTR in human airway epithelial cells. Moreover, there are no published studies examining TGF-β1 effects on the functional rescue of ΔF508-CFTR. Here we found that TGF-β1 inhibits CFTR biogenesis by reducing mRNA levels and protein abundance in primary differentiated human bronchial epithelial (HBE cells from non-CF individuals. TGF-β1 inhibits CFTR biogenesis without compromising the epithelial phenotype or integrity of HBE cells. TGF-β1 also inhibits biogenesis and impairs the functional rescue of ΔF508-CFTR in HBE cells from patients homozygous for the ΔF508 mutation. Our data indicate that activation of TGF-β1 signaling may inhibit CFTR function in non-CF individuals and may interfere with therapies directed at correcting the processing defect of ΔF508-CFTR in CF patients.

  1. Involvement of CFTR in Uterine Bicarbonate Secretion and the Fertilizing Capacity of Sperm

    Institute of Scientific and Technical Information of China (English)

    WangXiao,Fei; ZhouChen-Xi; ShiQi-Xian; YuanYu-Ying; YuMei-Kuen; LouisChukwuemekaAjonuma

    2005-01-01

    Cystic fibrosis transmembrane conductance regulator (CFFR)is a cAMP-activated chloride channel expressed in a wide variety of epithelial cells,mutations of which are responsible for the hallmark defective chloride secretion observed in cystic fibrosis(CF).Although CFTR has been implicated in bicarbonate secretion,its ability to directly mediate bicarbonate secretion of any physiological significance has not been shown.We demonstrate here that endometriaI epithelial ceils possess a CFTR-mediated bicarbonate transport mechanism.Co-culture of sperm with endometrial ceils treated with antisense oligonucleotide against CFTR,or with bicarbonate secretion-defective CF epithelial cells,resulted in lower sperm capacitation and egg-fertilizing ability.These results are consistent with a critical role of CFTR in controlling uterine bicarbonate secretion and the fertilizing capacity of sperm,providing a link between defective CFTR and lower female fertility in CF.

  2. Advancing clinical development pathways for new CFTR modulators in cystic fibrosis.

    Science.gov (United States)

    Mayer-Hamblett, Nicole; Boyle, Michael; VanDevanter, Donald

    2016-05-01

    Cystic fibrosis (CF) is a life-shortening genetic disease affecting approximately 70 000 individuals worldwide. Until recently, drug development efforts have emphasised therapies treating downstream signs and symptoms resulting from the underlying CF biological defect: reduced function of the CF transmembrane conductance regulator (CFTR) protein. The current CF drug development landscape has expanded to include therapies that enhance CFTR function by either restoring wild-type CFTR protein expression or increasing (modulating) the function of mutant CFTR proteins in cells. To date, two systemic small-molecule CFTR modulators have been evaluated in pivotal clinical trials in individuals with CF and specific mutantCFTRgenotypes that have led to regulatory review and/or approval. Advances in the discovery of CFTR modulators as a promising new class of therapies have been impressive, yet work remains to develop highly effective, disease-modifying modulators for individuals of all CF genotypes. The objectives of this review are to outline the challenges and opportunities in drug development created by systemic genotype-specific CFTR modulators, highlight the advantages of sweat chloride as an established biomarker of CFTR activity to streamline early-phase development and summarise options for later phase clinical trial designs that respond to the adoption of approved genotype-specific modulators into standard of care. An optimal development framework will be needed to move the most promising therapies efficiently through the drug development pipeline and ultimately deliver efficacious and safe therapies to all individuals with CF. PMID:26903594

  3. Depleted uranium in Kosovo: results of a survey by gamma spectrometry on soil samples.

    Science.gov (United States)

    Uyttenhove, J; Lemmens, M; Zizi, M

    2002-10-01

    The presence of depleted uranium in the soil of former Yugoslavia after the 1999 conflict raised great public concern all over the world. The so-called Balkan-syndrome is often linked with depleted uranium contamination. An excellent compilation of data about DU and its possible impact on health and environment can be found in the 1999 UNEP report and publications from the Swedish Radiation Protection Institute. Unfortunately, very few systematic and reliable data on the possible depleted uranium concentrations were until now available. Some of these rare data are only available on the web, without adequate information about the experimental procedure used. To clarify the situation, a systematic survey was started in the summer of 2000 as a collaborative effort between Ghent University (Physics Laboratory) and the Belgian Ministry of Defense (Medical Service). From 50 sites selected all over Kosovo, 150 soil samples were measured in the laboratory with a high-resolution gamma-spectrometer. Some sites (14) were explicitly selected based on military information on the use of depleted uranium munitions in the vicinity. After careful analysis we can conclude that there is no indication of any depleted uranium contamination on these 50 sites with a minimal detectable activity of 15 Bq; this corresponds approximately to 1 mg depleted uranium in a typical sample (100-150 g). PMID:12240731

  4. Restoration of NBD1 thermal stability is necessary and sufficient to correct ΔF508 CFTR folding and assembly

    OpenAIRE

    He, Lihua; Aleksandrov, Andrei A.; An, Jianli; Cui, Liying; Yang, Zhengrong; Brouillette, Christie G; Riordan, John R.

    2014-01-01

    CFTR (ABCC7), unique among ABC exporters as an ion channel, regulates ion and fluid transport in epithelial tissues. Loss of function due to mutations in the cftr gene causes cystic fibrosis (CF). The most common CF-causing mutation, the deletion of F508 (ΔF508) from the first nucleotide binding domain (NBD1) of CFTR, results in misfolding of the protein and clearance by cellular quality control systems. The ΔF508 mutation has two major impacts on CFTR: reduced thermal stability of NBD1 and d...

  5. The K+ channel opener 1-EBIO potentiates residual function of mutant CFTR in rectal biopsies from cystic fibrosis patients.

    Directory of Open Access Journals (Sweden)

    Eva K Roth

    Full Text Available BACKGROUND: The identification of strategies to improve mutant CFTR function remains a key priority in the development of new treatments for cystic fibrosis (CF. Previous studies demonstrated that the K⁺ channel opener 1-ethyl-2-benzimidazolone (1-EBIO potentiates CFTR-mediated Cl⁻ secretion in cultured cells and mouse colon. However, the effects of 1-EBIO on wild-type and mutant CFTR function in native human colonic tissues remain unknown. METHODS: We studied the effects of 1-EBIO on CFTR-mediated Cl⁻ secretion in rectal biopsies from 47 CF patients carrying a wide spectrum of CFTR mutations and 57 age-matched controls. Rectal tissues were mounted in perfused micro-Ussing chambers and the effects of 1-EBIO were compared in control tissues, CF tissues expressing residual CFTR function and CF tissues with no detectable Cl⁻ secretion. RESULTS: Studies in control tissues demonstrate that 1-EBIO activated CFTR-mediated Cl⁻ secretion in the absence of cAMP-mediated stimulation and potentiated cAMP-induced Cl⁻ secretion by 39.2±6.7% (P<0.001 via activation of basolateral Ca²⁺-activated and clotrimazole-sensitive KCNN4 K⁺ channels. In CF specimens, 1-EBIO potentiated cAMP-induced Cl⁻ secretion in tissues with residual CFTR function by 44.4±11.5% (P<0.001, but had no effect on tissues lacking CFTR-mediated Cl⁻ conductance. CONCLUSIONS: We conclude that 1-EBIO potentiates Cl⁻secretion in native CF tissues expressing CFTR mutants with residual Cl⁻ channel function by activation of basolateral KCNN4 K⁺ channels that increase the driving force for luminal Cl⁻ exit. This mechanism may augment effects of CFTR correctors and potentiators that increase the number and/or activity of mutant CFTR channels at the cell surface and suggests KCNN4 as a therapeutic target for CF.

  6. Results of the analysis of the intercomparison samples of the depleted uranium dioxide SR-30

    International Nuclear Information System (INIS)

    Samples of a homogeneous powder of depleted uranium dioxide, SR-30, were distributed to 38 laboratories in December 1980 for intercomparison of the precisions and accuracies of wet chemical assay. 16 laboratories reported their results. 12 laboratories applied titration procedures, 11 of them methods derived from the Davies and Gray procedure, 1 laboratory used controlled potential coulometry, 1 laboratory used fluorimetry, 1 laboratory U-232 spiking/alpha-spectrometry. One laboratory did not indicate the method applied. An analysis of variance yields for each laboratory the estimates of the measurement errors, the dissolution or treatment errors and the random calibration errors. The measurement errors vary between 0.01% and 3.41% relative. The differences to the reference value vary between -5.29% and +6.49% uranium, but 13 laboratories agree within +/-1% uranium with the reference value. The mean bias of these 13 laboratories is equal to +0.201% U. The standard deviation of the biases of these 13 laboratories is equal to 0.361% U. (author)

  7. CFTR activity and mitochondrial function

    Directory of Open Access Journals (Sweden)

    Angel Gabriel Valdivieso

    2013-01-01

    Full Text Available Cystic Fibrosis (CF is a frequent and lethal autosomal recessive disease, caused by mutations in the gene encoding the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR. Before the discovery of the CFTR gene, several hypotheses attempted to explain the etiology of this disease, including the possible role of a chloride channel, diverse alterations in mitochondrial functions, the overexpression of the lysosomal enzyme α-glucosidase and a deficiency in the cytosolic enzyme glucose 6-phosphate dehydrogenase. Because of the diverse mitochondrial changes found, some authors proposed that the affected gene should codify for a mitochondrial protein. Later, the CFTR cloning and the demonstration of its chloride channel activity turned the mitochondrial, lysosomal and cytosolic hypotheses obsolete. However, in recent years, using new approaches, several investigators reported similar or new alterations of mitochondrial functions in Cystic Fibrosis, thus rediscovering a possible role of mitochondria in this disease. Here, we review these CFTR-driven mitochondrial defects, including differential gene expression, alterations in oxidative phosphorylation, calcium homeostasis, oxidative stress, apoptosis and innate immune response, which might explain some characteristics of the complex CF phenotype and reveals potential new targets for therapy.

  8. The mitochondrial complex I activity is reduced in cells with impaired cystic fibrosis transmembrane conductance regulator (CFTR function.

    Directory of Open Access Journals (Sweden)

    Angel G Valdivieso

    Full Text Available Cystic fibrosis (CF is a frequent and lethal autosomal recessive disease. It results from different possible mutations in the CFTR gene, which encodes the CFTR chloride channel. We have previously studied the differential expression of genes in CF and CF corrected cell lines, and found a reduced expression of MTND4 in CF cells. MTND4 is a mitochondrial gene encoding the MTND4 subunit of the mitochondrial Complex I (mCx-I. Since this subunit is essential for the assembly and activity of mCx-I, we have now studied whether the activity of this complex was also affected in CF cells. By using Blue Native-PAGE, the in-gel activity (IGA of the mCx-I was found reduced in CFDE and IB3-1 cells (CF cell lines compared with CFDE/6RepCFTR and S9 cells, respectively (CFDE and IB3-1 cells ectopically expressing wild-type CFTR. Moreover, colon carcinoma T84 and Caco-2 cells, which express wt-CFTR, either treated with CFTR inhibitors (glibenclamide, CFTR(inh-172 or GlyH101 or transfected with a CFTR-specific shRNAi, showed a significant reduction on the IGA of mCx-I. The reduction of the mCx-I activity caused by CFTR inhibition under physiological or pathological conditions may have a profound impact on mitochondrial functions of CF and non-CF cells.

  9. CFTR Deletion in Mouse Testis Induces VDAC1 Mediated Inflammatory Pathway Critical for Spermatogenesis

    Science.gov (United States)

    Huijuan, Liao; Jiang, Xie; Ming, Yang; Huaqin, Sun; Wenming, Xu

    2016-01-01

    Cystic fibrosis is the most common genetic disease among Caucasians and affects tissues including lung, pancreas and reproductive tracts. It has been shown that Endoplasmic Reticulum (ER) stress and heat shock response are two major deregulated functional modules related to CFTR dysfunction. To identify the impact of CFTR deletion during spermatogenesis, we examined the expression of spermiogenesis-related genes in the testis of CFTR mutant mice (CF mice). We confirmed expression changes of MSY2, a germ cell specific RNA binding protein, resulting from deletion of CFTR in testis. Furthermore, real time PCR and Western blot results showed that an inflammatory response was activated in CF mice testis, as reflected by the altered expression of cytokines. We demonstrate for the first time that expression of MSY2 is decreased in CF mice. Our results suggest that CFTR deletion in testis influences inflammatory responses and these features are likely to be due to the unique environment of the seminiferous tubule during the spermatogenesis process. The current study also suggests avenues to understand the pathophysiology of CFTR during spermatogenesis and provides targets for the possible treatment of CFTR-related infertility. PMID:27483469

  10. CFTR Deletion in Mouse Testis Induces VDAC1 Mediated Inflammatory Pathway Critical for Spermatogenesis.

    Science.gov (United States)

    Yan, Chen; Lang, Qin; Huijuan, Liao; Jiang, Xie; Ming, Yang; Huaqin, Sun; Wenming, Xu

    2016-01-01

    Cystic fibrosis is the most common genetic disease among Caucasians and affects tissues including lung, pancreas and reproductive tracts. It has been shown that Endoplasmic Reticulum (ER) stress and heat shock response are two major deregulated functional modules related to CFTR dysfunction. To identify the impact of CFTR deletion during spermatogenesis, we examined the expression of spermiogenesis-related genes in the testis of CFTR mutant mice (CF mice). We confirmed expression changes of MSY2, a germ cell specific RNA binding protein, resulting from deletion of CFTR in testis. Furthermore, real time PCR and Western blot results showed that an inflammatory response was activated in CF mice testis, as reflected by the altered expression of cytokines. We demonstrate for the first time that expression of MSY2 is decreased in CF mice. Our results suggest that CFTR deletion in testis influences inflammatory responses and these features are likely to be due to the unique environment of the seminiferous tubule during the spermatogenesis process. The current study also suggests avenues to understand the pathophysiology of CFTR during spermatogenesis and provides targets for the possible treatment of CFTR-related infertility. PMID:27483469

  11. Predominant constitutive CFTR conductance in small airways

    Directory of Open Access Journals (Sweden)

    Lytle Christian

    2005-01-01

    Full Text Available Abstract Background The pathological hallmarks of chronic obstructive pulmonary disease (COPD are inflammation of the small airways (bronchiolitis and destruction of lung parenchyma (emphysema. These forms of disease arise from chronic prolonged infections, which are usually never present in the normal lung. Despite the fact that primary hygiene and defense of the airways presumably requires a well controlled fluid environment on the surface of the bronchiolar airway, very little is known of the fluid and electrolyte transport properties of airways of less than a few mm diameter. Methods We introduce a novel approach to examine some of these properties in a preparation of minimally traumatized porcine bronchioles of about 1 mm diameter by microperfusing the intact bronchiole. Results In bilateral isotonic NaCl Ringer solutions, the spontaneous transepithelial potential (TEP; lumen to bath of the bronchiole was small (mean ± sem: -3 ± 1 mV; n = 25, but when gluconate replaced luminal Cl-, the bionic Cl- diffusion potentials (-58 ± 3 mV; n = 25 were as large as -90 mV. TEP diffusion potentials from 2:1 NaCl dilution showed that epithelial Cl- permeability was at least 5 times greater than Na+ permeability. The anion selectivity sequence was similar to that of CFTR. The bionic TEP became more electronegative with stimulation by luminal forskolin (5 μM+IBMX (100 μM, ATP (100 μM, or adenosine (100 μM, but not by ionomycin. The TEP was partially inhibited by NPPB (100 μM, GlyH-101* (5–50 μM, and CFTRInh-172* (5 μM. RT-PCR gave identifying products for CFTR, α-, β-, and γ-ENaC and NKCC1. Antibodies to CFTR localized specifically to the epithelial cells lining the lumen of the small airways. Conclusion These results indicate that the small airway of the pig is characterized by a constitutively active Cl- conductance that is most likely due to CFTR.

  12. Evidence that CFTR is expressed in rat tracheal smooth muscle cells and contributes to bronchodilation

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    Mettey Yvette

    2006-08-01

    Full Text Available Abstract Background The airway functions are profoundly affected in many diseases including asthma, chronic obstructive pulmonary disease (COPD and cystic fibrosis (CF. CF the most common lethal autosomal recessive genetic disease is caused by mutations of the CFTR gene, which normally encodes a multifunctional and integral membrane protein, the CF transmembrane conductance regulator (CFTR expressed in airway epithelial cells. Methods To demonstrate that CFTR is also expressed in tracheal smooth muscle cells (TSMC, we used iodide efflux assay to analyse the chloride transports in organ culture of rat TSMC, immunofluorescence study to localize CFTR proteins and isometric contraction measurement on isolated tracheal rings to observe the implication of CFTR in the bronchodilation. Results We characterized three different pathways stimulated by the cAMP agonist forskolin and the isoflavone agent genistein, by the calcium ionophore A23187 and by hypo-osmotic challenge. The pharmacology of the cAMP-dependent iodide efflux was investigated in detail. We demonstrated in rat TSMC that it is remarkably similar to that of the epithelial CFTR, both for activation (using three benzo [c]quinolizinium derivatives and for inhibition (glibenclamide, DPC and CFTRinh-172. Using rat tracheal rings, we observed that the activation of CFTR by benzoquinolizinium derivatives in TSMC leads to CFTRinh-172-sensitive bronchodilation after constriction with carbachol. An immunolocalisation study confirmed expression of CFTR in tracheal myocytes. Conclusion Altogether, these observations revealed that CFTR in the airways of rat is expressed not only in the epithelial cells but also in tracheal smooth muscle cells leading to the hypothesis that this ionic channel could contribute to bronchodilation.

  13. CFTR suppresses tumor progression through miR-193b targeting urokinase plasminogen activator (uPA) in prostate cancer.

    Science.gov (United States)

    Xie, C; Jiang, X H; Zhang, J T; Sun, T T; Dong, J D; Sanders, A J; Diao, R Y; Wang, Y; Fok, K L; Tsang, L L; Yu, M K; Zhang, X H; Chung, Y W; Ye, L; Zhao, M Y; Guo, J H; Xiao, Z J; Lan, H Y; Ng, C F; Lau, K M; Cai, Z M; Jiang, W G; Chan, H C

    2013-05-01

    Cystic fibrosis (CF) transmembrane conductance regulator (CFTR) is expressed in the epithelial cells of a wide range of organs/tissues from which most cancers are derived. Although accumulating reports have indicated the association of cancer incidence with genetic variations in CFTR gene, the exact role of CFTR in cancer development and the possible underlying mechanism have not been elucidated. Here, we report that CFTR expression is significantly decreased in both prostate cancer cell lines and human prostate cancer tissue samples. Overexpression of CFTR in prostate cancer cell lines suppresses tumor progression (cell growth, adhesion and migration), whereas knockdown of CFTR leads to enhanced malignancies both in vitro and in vivo. In addition, we demonstrate that CFTR knockdown-enhanced cell proliferation, cell invasion and migration are significantly reversed by antibodies against either urokinase plasminogen activator (uPA) or uPA receptor (uPAR), which are known to be involved in various malignant traits of cancer development. More interestingly, overexpression of CFTR suppresses uPA by upregulating the recently described tumor suppressor microRNA-193b (miR-193b), and overexpression of pre-miR-193b significantly reverses CFTR knockdown-enhanced malignant phenotype and abrogates elevated uPA activity in prostate cancer cell line. Finally, we show that CFTR gene transfer results in significant tumor repression in prostate cancer xenografts in vivo. Taken together, the present study has demonstrated a previously undefined tumor-suppressing role of CFTR and its involvement in regulation of miR-193b in prostate cancer development. PMID:22797075

  14. Personalized medicine in cystic fibrosis: genistein supplementation as a treatment option for patients with a rare S1045Y-CFTR mutation.

    Science.gov (United States)

    Arora, Kavisha; Yarlagadda, Sunitha; Zhang, Weiqiang; Moon, ChangSuk; Bouquet, Erin; Srinivasan, Saumini; Li, Chunying; Stokes, Dennis C; Naren, Anjaparavanda P

    2016-08-01

    Cystic fibrosis (CF) is a life-shortening disease caused by the mutations that generate nonfunctional CF transmembrane conductance regulator (CFTR) protein. A rare serine-to-tyrosine (S1045Y) CFTR mutation was earlier reported to result in CF-associated fatality. We identified an African-American patient with the S1045Y mutation in CFTR, as well as a stop-codon mutation, who has a mild CF phenotype. The underlying mechanism of CF caused by S1045Y-CFTR has not been elucidated. In this study, we determined that S1045Y-CFTR exhibits twofold attenuated function compared with wild-type (WT)-CFTR. We report that serine-to-tyrosine mutation leads to increased tyrosine phosphorylation of S1045Y-CFTR, followed by recruitment and binding of E3-ubiquitin ligase c-cbl, resulting in enhanced ubiquitination and passage of S1045Y-CFTR in the endosome/lysosome degradative compartments. We demonstrate that inhibition of tyrosine phosphorylation partially rescues S1045Y-CFTR surface expression and function. Based on our findings, it could be suggested that consuming genistein (a tyrosine phosphorylation inhibitor) would likely ameliorate CF symptoms in individuals with S1045Y-CFTR, providing a unique personalized therapy for this rare CF mutation. PMID:27261451

  15. Recent results of the fully depleted back-illuminated CCD developed by Hamamatsu

    Science.gov (United States)

    Kamata, Yukiko; Miyazaki, Satoshi; Nakaya, Hidehiko; Tsuru, Takeshi Go; Takagi, Shin-ichiro; Tsunemi, Hiroshi; Miyata, Emi; Muramatsu, Masaharu; Suzuki, Hisanori; Miyaguchi, Kazuhisa

    2006-06-01

    We have been developing fully-depleted CCDs fabricated on N-type silicon wafer in collaboration with HAMAMATSU Photonics K.K.We have made several wafer runs to optimize the basic characteristics of the devices such as the charge transfer efficiency (CTE), the full-well capacity and the amplifier gain, followed by the optimization of the backside treatment to improve quantum efficiency (QE) in blue wavelengths. The optimization process is successfully completed, and Hamamatsu recently started to deliver the 2k × 4k (15 μm pixel) four-side buttable devices for acceptance evaluation at the National Astronomical Observatory of Japan. Based on the measured QE in the X-ray, the depletion depth reaches 200 μm with CTE as good as >0.999995 for serial and parallel directions and with readout noise of < 5 e- for 130 kHz readout. The size of charge diffusion is estimated to be < 7.5 μm (one sigma) for pinhole image at wavelength of 450 nm. The device flatness is < 15-20 μm, and the dark current is a few e-/hour/pixel at -100°C and ~ 20 e-/hour/pixel at -80°C.

  16. Rare large homozygous CFTR gene deletion in an Iranian patient with cystic fibrosis

    OpenAIRE

    Farjadian, Shirin; Moghtaderi, Mozhgan; Zuntini, Roberta; Ferrari, Simona

    2014-01-01

    Cystic fibrosis, a common autosomal recessive genetic disorder among Caucasians, is caused by defects in the transmembrane conductance regulatory (CFTR) gene. The analysis of CFTR gene mutations is useful to better characterize the disease, and for preconceptional screening, prenatal and preimplantation genetic diagnosis. Here we report the results of a genetic analysis in a 16-year-old boy from southwestern Iran diagnosed as having cystic fibrosis in infancy based on gastrointestinal and pul...

  17. Side chain and backbone contributions of Phe508 to CFTR folding

    Energy Technology Data Exchange (ETDEWEB)

    Thibodeau, Patrick H.; Brautigam, Chad A.; Machius, Mischa; Thomas, Philip J. (U. of Texas-SMED)

    2010-12-07

    Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), an integral membrane protein, cause cystic fibrosis (CF). The most common CF-causing mutant, deletion of Phe508, fails to properly fold. To elucidate the role Phe508 plays in the folding of CFTR, missense mutations at this position were generated. Only one missense mutation had a pronounced effect on the stability and folding of the isolated domain in vitro. In contrast, many substitutions, including those of charged and bulky residues, disrupted folding of full-length CFTR in cells. Structures of two mutant nucleotide-binding domains (NBDs) reveal only local alterations of the surface near position 508. These results suggest that the peptide backbone plays a role in the proper folding of the domain, whereas the side chain plays a role in defining a surface of NBD1 that potentially interacts with other domains during the maturation of intact CFTR.

  18. Endocytic Trafficking of CFTR in Health and Disease

    OpenAIRE

    Ameen, Nadia; Silvis, Mark; Bradbury, Neil A.

    2006-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) is a Cl-selective anion channel expressed in epithelial tissues. Mutations in CFTR lead to the debilitating genetic disease cystic fibrosis (CF). Within each epithelial cell, CFTR interacts with a large number of transient macromolecular complexes, many of which are involved in the trafficking and targeting of CFTR. Understanding how these complexes regulate the trafficking and fate of CFTR, provides a singular insight not only in...

  19. CFTR chloride channel as a molecular target of anthraquinone compounds in herbal laxatives

    Institute of Scientific and Technical Information of China (English)

    Hong YANG; Li-na XU; Cheng-yan HE; Xin LIU; Rou-yu FANG; Tong-hui MA

    2011-01-01

    Aim: To clarify whether CFTR is a molecular target of intestinal fluid secretion caused by the anthraquinone compounds from laxative herbal plants.Methods: A cell-based fluorescent assay to measure I- influx through CFTR chloride channel. A short-circuit current assay to measure transcellular Cl- current across single layer FRT cells and freshly isolated colon mucosa. A closed loop experiment to measure colon fluid secretion in vivo.Results: Anthraquinone compounds rhein, aloe-emodin and 1,8-dihydroxyanthraquinone (DHAN) stimulated l- influx through CFTR chloride channel in a dose-dependent manner in the presence of physiological concentration of cAMP. In the short-circuit current assay,the three compound enhanced Cl- currents in epithelia formed by CFTR-expressing FRT cells with EC5o values of 73±1.4, 56±1.7, and 50±0.5 μmol/L, respectively, and Rhein also enhanced Cl- current in freshly isolated rat colonic mucosa with a similar potency. These effects were completely reversed by the CFTR selective blocker CFTRinh-172. In in vivo closed loop experiments, rhein 2 mmol/L stimu-lated colonic fluid accumulation that was largely blocked by CFTRinh-172. The anthraquinone compounds did not elevate cAMP level in cultured FRT cells and rat colonic mucosa, suggesting a direct effect on CFTR activity.Conclusion: Natural anthraquinone compounds in vegetable laxative drugs are CFTR potsntiators that stimulated colonic chloride and fluid secretion. Thus CFTR chloride channel is a molecular target of vegetable laxative drugs.

  20. A truncated CFTR protein rescues endogenous ΔF508-CFTR and corrects chloride transport in mice

    OpenAIRE

    Cormet-Boyaka, Estelle; Jeong S Hong; Berdiev, Bakhram K.; James A Fortenberry; Rennolds, Jessica; Clancy, J. P.; Benos, Dale J.; Boyaka, Prosper N.; Sorscher, Eric J.

    2009-01-01

    Cystic fibrosis (CF) is most frequently associated with deletion of phenylalanine at position 508 (ΔF508) in the CF transmembrane conductance regulator (CFTR) protein. The ΔF508-CFTR mutant protein exhibits a folding defect that affects its processing and impairs chloride-channel function. This study aimed to determine whether CFTR fragments approximately half the size of wild-type CFTR and complementary to the portion of CFTR bearing the mutation can specifically rescue the processing of end...

  1. A host defense mechanism involving CFTR-mediated bicarbonate secretion in bacterial prostatitis.

    Directory of Open Access Journals (Sweden)

    Chen Xie

    Full Text Available BACKGROUND: Prostatitis is associated with a characteristic increase in prostatic fluid pH; however, the underlying mechanism and its physiological significance have not been elucidated. METHODOLOGY/PRINCIPAL FINDINGS: In this study a primary culture of rat prostatic epithelial cells and a rat prostatitis model were used. Here we reported the involvement of CFTR, a cAMP-activated anion channel conducting both Cl(- and HCO(3(-, in mediating prostate HCO(3(- secretion and its possible role in bacterial killing. Upon Escherichia coli (E. coli-LPS challenge, the expression of CFTR and carbonic anhydrase II (CA II, along with several pro-inflammatory cytokines was up-regulated in the primary culture of rat prostate epithelial cells. Inhibiting CFTR function in vitro or in vivo resulted in reduced bacterial killing by prostate epithelial cells or the prostate. High HCO(3(- content (>50 mM, rather than alkaline pH, was found to be responsible for bacterial killing. The direct action of HCO(3(- on bacterial killing was confirmed by its ability to increase cAMP production and suppress bacterial initiation factors in E. coli. The relevance of the CFTR-mediated HCO(3(- secretion in humans was demonstrated by the upregulated expression of CFTR and CAII in human prostatitis tissues. CONCLUSIONS/SIGNIFICANCE: The CFTR and its mediated HCO(3(- secretion may be up-regulated in prostatitis as a host defense mechanism.

  2. Acute administration of ivacaftor to people with cystic fibrosis and a G551D-CFTR mutation reveals smooth muscle abnormalities

    Science.gov (United States)

    Adam, Ryan J.; Hisert, Katherine B.; Dodd, Jonathan D.; Grogan, Brenda; Launspach, Janice L.; Barnes, Janel K.; Gallagher, Charles G.; Sieren, Jered P.; Gross, Thomas J.; Fischer, Anthony J.; Cavanaugh, Joseph E.; Hoffman, Eric A.; Singh, Pradeep K.; Welsh, Michael J.; McKone, Edward F.; Stoltz, David A.

    2016-01-01

    Background Airflow obstruction is common in cystic fibrosis (CF), yet the underlying pathogenesis remains incompletely understood. People with CF often exhibit airway hyperresponsiveness, CF transmembrane conductance regulator (CFTR) is present in airway smooth muscle (ASM), and ASM from newborn CF pigs has increased contractile tone, suggesting that loss of CFTR causes a primary defect in ASM function. We hypothesized that restoring CFTR activity would decrease smooth muscle tone in people with CF. Methods To increase or potentiate CFTR function, we administered ivacaftor to 12 adults with CF with the G551D-CFTR mutation; ivacaftor stimulates G551D-CFTR function. We studied people before and immediately after initiation of ivacaftor (48 hours) to minimize secondary consequences of CFTR restoration. We tested smooth muscle function by investigating spirometry, airway distensibility, and vascular tone. Results Ivacaftor rapidly restored CFTR function, indicated by reduced sweat chloride concentration. Airflow obstruction and air trapping also improved. Airway distensibility increased in airways less than 4.5 mm but not in larger-sized airways. To assess smooth muscle function in a tissue outside the lung, we measured vascular pulse wave velocity (PWV) and augmentation index, which both decreased following CFTR potentiation. Finally, change in distensibility of <4.5-mm airways correlated with changes in PWV. Conclusions Acute CFTR potentiation provided a unique opportunity to investigate CFTR-dependent mechanisms of CF pathogenesis. The rapid effects of ivacaftor on airway distensibility and vascular tone suggest that CFTR dysfunction may directly cause increased smooth muscle tone in people with CF and that ivacaftor may relax smooth muscle. Funding This work was funded in part from an unrestricted grant from the Vertex Investigator-Initiated Studies Program. PMID:27158673

  3. Activation of CFTR-mediated Cl- Transport by Magnolin

    Institute of Scientific and Technical Information of China (English)

    JIN Ling-ling; LIU Xin; SUN Yan; LIN Sen; ZHOU Na; XU Li-na; YU BO; HOU Shu-guang; YANG Hong

    2008-01-01

    Magnolin is a herbal compound from Magnolia biondii Pamp.It possesses numerous biological activities.Cystic fibrosis transmembrane conductance regulator(CFTR)is all epithelial chloride channel that plays a key role in the fluid secretion of various exocrine organs.In the present study,the activation of CFTR-mediated chloride transport by magnolin is indentified and characterized.In CFTR stably trailsfected FRT cells.magnolin increases CFTR Cl- currents in a concentration-dependent manner.The activation of magnolin on CFTR is rapid,reversible,and cAMP-dependent.Magnolin does not elevate cellular cAMP level.indicating that it activates CFTR by direct binding and interaction with CFTR protein.Magnolin selectively activates wildtype CFTR rather than mutant CFTIL Magnolin may present a novel class of therapeutic lead compound for the treatment of diseases associated with reduced CFTR function such as keratoconjunctivitis sicca,idiopathic chronic pancreatiti,and chromc constipation.

  4. Important role of platelets in modulating endotoxin-induced lung inflammation in CFTR-deficient mice.

    Directory of Open Access Journals (Sweden)

    Caiqi Zhao

    Full Text Available Mutation of CFTR (cystic fibrosis transmembrane conductance regulator leads to cystic fibrosis (CF. Patients with CF develop abnormalities of blood platelets and recurrent lung inflammation. However, whether CFTR-mutated platelets play a role in the development of lung inflammation is elusive. Therefore, we intratracheally challenged wildtype and F508del (a common type of CFTR mutation mice with LPS to observe changes of F508del platelets in the peripheral blood and indexes of lung inflammation (BAL neutrophils and protein levels. Furthermore, we investigated whether or not and how F508del platelets modulate the LPS-induced acute lung inflammation by targeting anti-platelet aggregation, depletion of neutrophils, reconstitution of bone marrow or neutrophils, blockade of P-selectin glycoprotein ligand-1 (PSGL-1, platelet activating factor (PAF, and correction of mutated CFTR trafficking. We found that LPS-challenged F508del mice developed severe thrombocytopenia and had higher levels of plasma TXB2 coincided with neutrophilic lung inflammation relative to wildtype control. Inhibition of F508del platelet aggregation or depletion of F508del neutrophils diminished the LPS-induced lung inflammation in the F508del mice. Moreover, wildtype mice reconstituted with either F508del bone marrow or neutrophils developed worse thrombocytopenia. Blocking PSGL-1, platelet activating factor (PAF, or rectifying trafficking of mutated CFTR in F508del mice diminished and alveolar neutrophil transmigration in the LPS-challenged F508del mice. These findings suggest that F508del platelets and their interaction with neutrophils are requisite for the development of LPS-induced lung inflammation and injury. As such, targeting platelets might be an emerging strategy for dampening recurrent lung inflammation in cystic fibrosis patients.

  5. Mechanisms of CFTR functional variants that impair regulated bicarbonate permeation and increase risk for pancreatitis but not for cystic fibrosis.

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    Jessica LaRusch

    2014-07-01

    Full Text Available CFTR is a dynamically regulated anion channel. Intracellular WNK1-SPAK activation causes CFTR to change permeability and conductance characteristics from a chloride-preferring to bicarbonate-preferring channel through unknown mechanisms. Two severe CFTR mutations (CFTRsev cause complete loss of CFTR function and result in cystic fibrosis (CF, a severe genetic disorder affecting sweat glands, nasal sinuses, lungs, pancreas, liver, intestines, and male reproductive system. We hypothesize that those CFTR mutations that disrupt the WNK1-SPAK activation mechanisms cause a selective, bicarbonate defect in channel function (CFTRBD affecting organs that utilize CFTR for bicarbonate secretion (e.g. the pancreas, nasal sinus, vas deferens but do not cause typical CF. To understand the structural and functional requirements of the CFTR bicarbonate-preferring channel, we (a screened 984 well-phenotyped pancreatitis cases for candidate CFTRBD mutations from among 81 previously described CFTR variants; (b conducted electrophysiology studies on clones of variants found in pancreatitis but not CF; (c computationally constructed a new, complete structural model of CFTR for molecular dynamics simulation of wild-type and mutant variants; and (d tested the newly defined CFTRBD variants for disease in non-pancreas organs utilizing CFTR for bicarbonate secretion. Nine variants (CFTR R74Q, R75Q, R117H, R170H, L967S, L997F, D1152H, S1235R, and D1270N not associated with typical CF were associated with pancreatitis (OR 1.5, p = 0.002. Clones expressed in HEK 293T cells had normal chloride but not bicarbonate permeability and conductance with WNK1-SPAK activation. Molecular dynamics simulations suggest physical restriction of the CFTR channel and altered dynamic channel regulation. Comparing pancreatitis patients and controls, CFTRBD increased risk for rhinosinusitis (OR 2.3, p<0.005 and male infertility (OR 395, p<<0.0001. WNK1-SPAK pathway-activated increases in

  6. CFTR, PRSS1 und SPINK1 Varianten bei chronischer Pankreatitis

    OpenAIRE

    Rosendahl, Jonas

    2010-01-01

    Chronic pancreatitis (CP) is defined as a continuing or relapsing inflammatory disease of the pancreas, leading to endocrine and/or exocrine insufficiency and irreversible morphological changes. Currently, it is thought that the imbalance of pancreatic proteases and their inhibitors results in the development of chronic pancreatitis. Until now, genetic variations of four genes have been associated to chronic pancreatitis: PRSS1, PRSS2, SPINK1 and CFTR. Since direct DNA-sequencing has becom...

  7. Three charged amino acids in extracellular loop 1 are involved in maintaining the outer pore architecture of CFTR.

    Science.gov (United States)

    Cui, Guiying; Rahman, Kazi S; Infield, Daniel T; Kuang, Christopher; Prince, Chengyu Z; McCarty, Nael A

    2014-08-01

    The cystic fibrosis (CF) transmembrane conductance regulator (CFTR) bears six extracellular loops (ECL1-6); ECL1 is the site of several mutations associated with CF. Mutation R117H has been reported to reduce current amplitude, whereas D110H, E116K, and R117C/L/P may impair channel stability. We hypothesized that these amino acids might not be directly involved in ion conduction and permeation but may contribute to stabilizing the outer vestibule architecture in CFTR. We used cRNA injected oocytes combined with electrophysiological techniques to test this hypothesis. Mutants bearing cysteine at these sites were not functionally modified by extracellular MTS reagents and were blocked by GlyH-101 similarly to WT-CFTR. These results suggest that these three residues do not contribute directly to permeation in CFTR. In contrast, mutants D110R-, E116R-, and R117A-CFTR exhibited instability of the open state and significantly shortened burst duration compared with WT-CFTR and failed to be locked into the open state by AMP-PNP (adenosine 5'-(β,γ-imido) triphosphate); charge-retaining mutants showed mainly the full open state with comparably longer open burst duration. These interactions suggest that these ECL1 residues might be involved in maintaining the outer pore architecture of CFTR. A CFTR homology model suggested that E116 interacts with R104 in both the closed and open states, D110 interacts with K892 in the fully closed state, and R117 interacts with E1126 in the open state. These interactions were confirmed experimentally. The results suggest that D110, E116, and R117 may contribute to stabilizing the architecture of the outer pore of CFTR by interactions with other charged residues. PMID:25024266

  8. CFTR gene mutations in isolated chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Pignatti, P.F.; Bombien, C.; Marigo, C. [and others

    1994-09-01

    In order to identify a possible hereditary predisposition to the development of chronic obstructive pulmonary disease (COPD), we have looked for the presence of cystic fibrosis transmembrane regulator (CFTR) gene DNA sequence modifications in 28 unrelated patients with no signs of cystic fibrosis. The known mutations in Italian CF patients, as well as the most frequent worldwide CF mutations, were investigated. In addition, a denaturing gradient gel electrophoresis analysis of about half of the coding sequence of the gene in 56 chromosomes from the patients and in 102 chromosomes from control individuals affected by other pulmonary diseases and from normal controls was performed. Nine different CFTR gene mutations and polymorphisms were found in seven patients, a highly significant increase over controls. Two of the patients were compound heterozygotes. Two frequent CF mutations were detected: deletion F508 and R117H; two rare CF mutations: R1066C and 3667ins4; and five CF sequence variants: R75Q (which was also described as a disease-causing mutation in male sterility cases due to the absence of the vasa deferentia), G576A, 2736 A{r_arrow}G, L997F, and 3271+18C{r_arrow}T. Seven (78%) of the mutations are localized in transmembrane domains. Six (86%) of the patients with defined mutations and polymorphisms had bronchiectasis. These results indicate that CFTR gene mutations and sequence alterations may be involved in the etiopathogenesis of some cases of COPD.

  9. Analysis of Y chromosome microdeletions and CFTR gene mutations as genetic markers of infertility in Serbian men

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    Dinić Jelena

    2007-01-01

    Full Text Available Background/Aim. Impaired fertility of a male partner is the main cause of infertility in up to one half of all infertile couples. At the genetic level, male infertility can be caused by chromosome aberrations or gene mutations. The presence and types of Y chromosome microdeletions and cystic fybrosis transmembrane conductance regulator (CFTR gene mutations as genetic cause of male infertility was tested in Serbian men. The aim of this study was to analyze CFTR gene mutations and Y chromosome microdelations as potential causes of male infertility in Serbian patients, as well as to test the hypothesis that CFTR mutations in infertile men are predominantly located in the several last exons of the gene. Methods. This study has encompassed 33 men with oligo- or azoospermia. The screening for Y chromosome microdeletions in the azoospermia factor (AZF region was performed by multiplex PCR analysis. The screening of the CFTR gene was performed by denaturing gradient gel electrophoresis (DGGE method. Results. Deletions on Y chromosome were detected in four patients, predominantly in AZFc region (four of total six deletions. Mutations in the CFTR gene were detected on eight out of 66 analyzed chromosomes of infertile men. The most common mutation was F508del (six of total eight mutations. Conclusion. This study confirmed that both Y chromosome microdeletions and CFTR gene mutations played important role in etiology of male infertility in Serbian infertile men. Genetic testing for Y chromosome microdeletions and CFTR gene mutations has been introduced in routine diagnostics and offered to couples undergoing assisted reproduction techniques. Considering that both the type of Y chromosome microdeletion and the type of CFTR mutation have a prognostic value, it is recommended that AZF and CFTR genotyping should not only be performed in patients with reduced sperm quality before undergoing assisted reproduction, but also for the purpose of preimplantation and

  10. Dexamethasone regulates CFTR expression in Calu-3 cells with the involvement of chaperones HSP70 and HSP90.

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    Luiz Felipe M Prota

    Full Text Available BACKGROUND: Dexamethasone is widely used for pulmonary exacerbation in patients with cystic fibrosis, however, not much is known about the effects of glucocorticoids on the wild-type cystic fibrosis channel transmembrane regulator (CFTR. Our aim was to determine the effects of dexamethasone treatment on wild-type CFTR expression. METHODS AND RESULTS: Dose-response (1 nM to 10 µM and time course (3 to 48 h curves were generated for dexamethasone for mRNA expression in Calu-3 cells using a real-time PCR. Within 24 h, dexamethasone (10 nM showed a 0.3-fold decrease in CFTR mRNA expression, and a 3.2-fold increase in αENaC mRNA expression compared with control groups. Dexamethasone (10 nM induced a 1.97-fold increase in the total protein of wild-type CFTR, confirmed by inhibition by mifepristone. To access surface protein expression, biotinylation followed by Western blotting showed that dexamethasone treatment led to a 2.35-fold increase in the amount of CFTR in the cell surface compared with the untreated control groups. Once protein translation was inhibited with cycloheximide, dexamethasone could not increase the amount of CFTR protein. Protein stability was assessed by inhibition of protein synthesis with cycloheximide (50 µg/ml at different times in cells treated with dexamethasone and in untreated cells. Dexamethasone did not alter the degradation of wild-type CFTR. Assessment of the B band of CFTR within 15 min of metabolic pulse labeling showed a 1.5-fold increase in CFTR protein after treatment with dexamethasone for 24 h. Chaperone 90 (HSP90 binding to CFTR increased 1.55-fold after treatment with dexamethasone for 24 h, whereas chaperone 70 (HSP70 binding decreased 0.30 fold in an immunoprecipitation assay. CONCLUSION: Mature wild-type CFTR protein is regulated by dexamethasone post transcription, involving cotranslational mechanisms with HSP90 and HSP70, which enhances maturation and expression of wild-type CFTR.

  11. Modulation of CFTR gating by permeant ions.

    Science.gov (United States)

    Yeh, Han-I; Yeh, Jiunn-Tyng; Hwang, Tzyh-Chang

    2015-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) is unique among ion channels in that after its phosphorylation by protein kinase A (PKA), its ATP-dependent gating violates microscopic reversibility caused by the intimate involvement of ATP hydrolysis in controlling channel closure. Recent studies suggest a gating model featuring an energetic coupling between opening and closing of the gate in CFTR's transmembrane domains and association and dissociation of its two nucleotide-binding domains (NBDs). We found that permeant ions such as nitrate can increase the open probability (Po) of wild-type (WT) CFTR by increasing the opening rate and decreasing the closing rate. Nearly identical effects were seen with a construct in which activity does not require phosphorylation of the regulatory domain, indicating that nitrate primarily affects ATP-dependent gating steps rather than PKA-dependent phosphorylation. Surprisingly, the effects of nitrate on CFTR gating are remarkably similar to those of VX-770 (N-(2,4-Di-tert-butyl-5-hydroxyphenyl)-4-oxo-1,4-dihydroquinoline-3-carboxamide), a potent CFTR potentiator used in clinics. These include effects on single-channel kinetics of WT CFTR, deceleration of the nonhydrolytic closing rate, and potentiation of the Po of the disease-associated mutant G551D. In addition, both VX-770 and nitrate increased the activity of a CFTR construct lacking NBD2 (ΔNBD2), indicating that these gating effects are independent of NBD dimerization. Nonetheless, whereas VX-770 is equally effective when applied from either side of the membrane, nitrate potentiates gating mainly from the cytoplasmic side, implicating a common mechanism for gating modulation mediated through two separate sites of action. PMID:25512598

  12. A novel treatment of cystic fibrosis acting on-target: cysteamine plus epigallocatechin gallate for the autophagy-dependent rescue of class II-mutated CFTR.

    Science.gov (United States)

    Tosco, A; De Gregorio, F; Esposito, S; De Stefano, D; Sana, I; Ferrari, E; Sepe, A; Salvadori, L; Buonpensiero, P; Di Pasqua, A; Grassia, R; Leone, C A; Guido, S; De Rosa, G; Lusa, S; Bona, G; Stoll, G; Maiuri, M C; Mehta, A; Kroemer, G; Maiuri, L; Raia, V

    2016-08-01

    We previously reported that the combination of two safe proteostasis regulators, cysteamine and epigallocatechin gallate (EGCG), can be used to improve deficient expression of the cystic fibrosis transmembrane conductance regulator (CFTR) in patients homozygous for the CFTR Phe508del mutation. Here we provide the proof-of-concept that this combination treatment restored CFTR function and reduced lung inflammation (Ptreatment in vitro. We assessed individual responses to cysteamine plus EGCG in a single-centre, open-label phase-2 trial. The combination treatment decreased sweat chloride from baseline, increased both CFTR protein and function in nasal cells, restored autophagy in such cells, decreased CXCL8 and TNF-α in the sputum, and tended to improve respiratory function. These positive effects were particularly strong in patients carrying Phe508del CFTR mutations in homozygosity or heterozygosity. However, a fraction of patients bearing other CFTR mutations failed to respond to therapy. Importantly, the same patients whose primary nasal brushed cells did not respond to cysteamine plus EGCG in vitro also exhibited deficient therapeutic responses in vivo. Altogether, these results suggest that the combination treatment of cysteamine plus EGCG acts 'on-target' because it can only rescue CFTR function when autophagy is functional (in mice) and improves CFTR function when a rescuable protein is expressed (in mice and men). These results should spur the further clinical development of the combination treatment. PMID:27035618

  13. CFTR mediates bicarbonate-dependent activation of miR-125b in preimplantation embryo development

    Institute of Scientific and Technical Information of China (English)

    Yong Chao Lu; Alvin Chun Hang Ma; Anskar Yu Hung Leung; He Feng Huang; Hsiao Chang Chan; Hui Chen; Kin Lam Fok; Lai Ling Tsang; Mei Kuen Yu; Xiao Hu Zhang; Jing Chen; Xiaohua Jiang; Yiu Wa Chung

    2012-01-01

    Although HCO3-is known to be required for early embryo development,its exact role remains elusive.Here we report that HCO3-acts as an environmental cue in regulating miR-125b expression through CFTR-mediated influx during preimplantation embryo development.The results show that the effect of HCO3-on preimplantation embryo development can be suppressed by interfering the function of a HCO3--conducting channel,CFTR,by a specific inhibitor or gene knockout.Removal of extracellular HCO3-or inhibition of CFTR reduces miR-125b expression in 2 cell-stage mouse embryos.Knockdown of miR-125b mimics the effect of HCO3-removal and CFTR inhibition,while injection of miR-125b precursor reverses it.Downregulation of miR-125b upregulates p53 cascade in both human and mouse embryos.The activation of miR-125b is shown to be mediated by sAC/PKA-dependent nuclear shuttling of NF-KB.These results have revealed a critical role of CFTR in signal transduction linking the environmental HCO3-to activation of miR-125b during preimplantation embryo development and indicated the importance of ion channels in regulation of miRNAs.

  14. Pathophysiologic consequences following inhibition of a CFTR-dependent developmental cascade in the lung

    Directory of Open Access Journals (Sweden)

    Larson Janet E

    2005-02-01

    Full Text Available Abstract Background Examination of late gestation developmental genes in vivo may be limited by early embryonic lethality and compensatory mechanisms. This problem is particularly apparent in evaluating the developmental role of the cystic fibrosis transmembrane conductance regulator (CFTR gene in the cystic fibrosis (CF phenotype. A previously described transient in utero knockout (TIUKO technology was used to address the developmental role of CFTR in the rat lung. Results Rat fetuses transiently treated with antisense cftr in utero developed pathology that replicated aspects of the human CF phenotype. The TIUKO CF rat developed lung fibrosis, chronic inflammation, reactive airway disease, and the CF Antigen (MRP8/14, a marker for CF in human patients, was expressed. Conclusions The transient in utero antisense technology can be used to evaluate genes that exhibit either early lethality or compensating gene phenotypes. In the lung CFTR is part of a developmental cascade for normal secretory cell differentiation. Absence of CFTR results in a constitutive inflammatory process that is involved in some aspects of CF pathophysiology.

  15. Lumacaftor/ivacaftor combination for cystic fibrosis patients homozygous for Phe508del-CFTR.

    Science.gov (United States)

    Zhang, W; Zhang, X; Zhang, Y H; Strokes, D C; Naren, A P

    2016-04-01

    Cystic fibrosis (CF) is a life-shortening inherited disease caused by the loss or dysfunction of the CF transmembrane conductance regulator (CFTR) channel activity resulting from mutations in the CFTR gene. Phe508del is the most prevalent mutation, with approximately 90% of all CF patients carrying it on at least one allele. Over the past two or three decades, significant progress has been made in understanding the pathogenesis of CF, and in the development of effective CF therapies. The approval of Orkambi® (lumacaftor/ivacaftor) marks another milestone in CF therapeutics development, which, with the advent of personalized medicine, could potentially revolutionize CF care and management. This article reviews the rationale, progress and future direction in the development of lumacaftor/ivacaftor combination to treat CF patients homozygous for the Phe508del-CFTR mutation. PMID:27252987

  16. Regulation of CFTR Expression and Arginine Vasopressin Activity Are Dependent on Polycystin-1 in Kidney-Derived Cells

    Directory of Open Access Journals (Sweden)

    Carolina Monteiro de Lemos Barbosa

    2016-01-01

    Full Text Available Background: Autosomal dominant polycystic kidney disease (ADPKD is characterized by the development of multiple, progressive, fluid-filled renal cysts that distort the renal parenchyma, leading to end-stage renal failure, mainly after the fifth decade of life. ADPKD is caused by a mutation in the PKD1 or PKD2 genes that encode polycystin-1 (PC-1 and polycystin-2 (PC-2, respectively. PC-1 is an important regulator of several signaling pathways and PC-2 is a nonselective calcium channel. The CFTR chloride channel is responsible for driving net fluid secretion into the cysts, promoting cyst growth. Arginine vasopressin hormone (AVP, in turn, is capable of increasing cystic intracellular cAMP, contributing to cell proliferation, transepithelial fluid secretion, and therefore to disease progression. The aim of this study was to assess if AVP can modulate CFTR and whether PC-1 plays a role in this potential modulation. Methods: M1 cells, derived from mouse cortical collecting duct, were used in the current work. The cells were treated with 10-7 M AVP hormone and divided into two main groups: transfected cells superexpressing PC-1 (Transf and cells not transfected (Ctrl. CFTR expression was assessed by immunodetection, CFTR mRNA levels were quantified by quantitative reverse transcription-polymerase chain reaction, and CFTR net ion transport was measured using the Ussing chamber technique. Results: AVP treatment increased the levels of CFTR protein and mRNA. CFTR short-circuit currents were also increased. However, when PC-1 was overexpressed in M1 cells, no increase in any of these parameters was detected. Conclusions: CFTR chloride channel expression is increased by AVP in M1 cells and PC-1 is capable of regulating this modulation.

  17. The Gulf War depleted uranium cohort at 20 years: bioassay results and novel approaches to fragment surveillance.

    Science.gov (United States)

    McDiarmid, Melissa A; Gaitens, Joanna M; Hines, Stella; Breyer, Richard; Wong-You-Cheong, Jade J; Engelhardt, Susan M; Oliver, Marc; Gucer, Patricia; Kane, Robert; Cernich, Alison; Kaup, Bruce; Hoover, Dennis; Gaspari, Anthony A; Liu, Juan; Harberts, Erin; Brown, Lawrence; Centeno, Jose A; Gray, Patrick J; Xu, Hanna; Squibb, Katherine S

    2013-04-01

    During the 1991 GulfWar, U.S. service members were exposed to depleted uranium (DU) through friendly-fire incidents involving DU munitions and vehicles protected by DU armor. Routes of exposure to DU involved inhalation of soluble and insoluble DU oxide particles, wound contamination, and retained embedded DU metal fragments that continue to oxidize in situ and release DU to the systemic circulation. A biennial health surveillance program established for this group of Veterans by the U.S. Department of Veterans Affairs has shown continuously elevated urine DU concentrations in the subset of veterans with embedded fragments for over 20 years. While the 2011 assessment was comprehensive, few clinically significant U-related health effects were observed. This report is focused on health outcomes associated with two primary target organs of concern for long term effects of this combat-related exposure to DU. Renal biomarkers showed minimal DU-related effects on proximal tubule function and cytotoxicity, but significant biomarker results were observed when urine concentrations of multiple metals also found in fragments were examined together. Pulmonary tests and questionnaire results indicate that pulmonary function after 20 y remains within the clinical normal range. Imaging of DU embedded fragment-associated tissue for signs of inflammatory or proliferative reactions possibly associated with foreign body transformation or with local alpha emissions from DU was also conducted using PET-CT and ultrasound. These imaging tools may be helpful in guiding decisions regarding removal of fragments. PMID:23439138

  18. A novel CFTR mutation found in a Chinese patient with cystic fibrosis

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Background Cystic fibrosis (CF) is rare in Chinese. We investigated the mutations in the gene of cystic fibrosis transmembrane conductance regulator (CFTR) in a Chinese CF patient and reviewed the clinical features, gene mutations in Chinese CF cases. Methods Blood samples were collected from a previously reported CF girl and her parents. The 24 coding exons of CFTR of the proband were amplified and sequenced. Results A Chinese girl of 16 years old was diagnosed as CF at the age of 14. She had recurrent productive cough with bronchiectasis in bilateral upper lobes, parasinusitis and otitis media, but without pancreatic involvement. Her sweat chloride was (108.9 ±3.3) mmol/L. A heterozygous novel missense mutation of 699 C→A which results in the amino acid change of N189K was identified in exon 5. In addition, a heterozygous 3821-3823 delT mutation in exon 19 was found in CFTR. The mutation 699C→A was inherited from her father, and the 3821-3823delT mutation was from her mother. Twenty patients with CF in Chinese reported from 1974 to 2004 were also reviewed. DelF508 mutation was not found in the nine cases whose CFTR mutations were analyzed. Conclusions The CF proband carries two heterozygous mutations (699C→A and 3821-3823delT) in CFTR. 699C→A mutation is a novel mutation which is not reported previously. Review of reported Chinese cases suggests that the genotype of Chinese CF may be different from those of white cases. More studies are needed to understand the spectra of CFTR and clinical CF features in Chinese.

  19. Ribosomal Stalk Protein Silencing Partially Corrects the ΔF508-CFTR Functional Expression Defect.

    Science.gov (United States)

    Veit, Guido; Oliver, Kathryn; Apaja, Pirjo M; Perdomo, Doranda; Bidaud-Meynard, Aurélien; Lin, Sheng-Ting; Guo, Jingyu; Icyuz, Mert; Sorscher, Eric J; Hartman Iv, John L; Lukacs, Gergely L

    2016-05-01

    The most common cystic fibrosis (CF) causing mutation, deletion of phenylalanine 508 (ΔF508 or Phe508del), results in functional expression defect of the CF transmembrane conductance regulator (CFTR) at the apical plasma membrane (PM) of secretory epithelia, which is attributed to the degradation of the misfolded channel at the endoplasmic reticulum (ER). Deletion of phenylalanine 670 (ΔF670) in the yeast oligomycin resistance 1 gene (YOR1, an ABC transporter) of Saccharomyces cerevisiae phenocopies the ΔF508-CFTR folding and trafficking defects. Genome-wide phenotypic (phenomic) analysis of the Yor1-ΔF670 biogenesis identified several modifier genes of mRNA processing and translation, which conferred oligomycin resistance to yeast. Silencing of orthologues of these candidate genes enhanced the ΔF508-CFTR functional expression at the apical PM in human CF bronchial epithelia. Although knockdown of RPL12, a component of the ribosomal stalk, attenuated the translational elongation rate, it increased the folding efficiency as well as the conformational stability of the ΔF508-CFTR, manifesting in 3-fold augmented PM density and function of the mutant. Combination of RPL12 knockdown with the corrector drug, VX-809 (lumacaftor) restored the mutant function to ~50% of the wild-type channel in primary CFTRΔF508/ΔF508 human bronchial epithelia. These results and the observation that silencing of other ribosomal stalk proteins partially rescue the loss-of-function phenotype of ΔF508-CFTR suggest that the ribosomal stalk modulates the folding efficiency of the mutant and is a potential therapeutic target for correction of the ΔF508-CFTR folding defect. PMID:27168400

  20. Ribosomal Stalk Protein Silencing Partially Corrects the ΔF508-CFTR Functional Expression Defect

    Science.gov (United States)

    Veit, Guido; Oliver, Kathryn; Apaja, Pirjo M.; Perdomo, Doranda; Bidaud-Meynard, Aurélien; Guo, Jingyu; Icyuz, Mert; Sorscher, Eric J.; Hartman IV, John L.; Lukacs, Gergely L.

    2016-01-01

    The most common cystic fibrosis (CF) causing mutation, deletion of phenylalanine 508 (ΔF508 or Phe508del), results in functional expression defect of the CF transmembrane conductance regulator (CFTR) at the apical plasma membrane (PM) of secretory epithelia, which is attributed to the degradation of the misfolded channel at the endoplasmic reticulum (ER). Deletion of phenylalanine 670 (ΔF670) in the yeast oligomycin resistance 1 gene (YOR1, an ABC transporter) of Saccharomyces cerevisiae phenocopies the ΔF508-CFTR folding and trafficking defects. Genome-wide phenotypic (phenomic) analysis of the Yor1-ΔF670 biogenesis identified several modifier genes of mRNA processing and translation, which conferred oligomycin resistance to yeast. Silencing of orthologues of these candidate genes enhanced the ΔF508-CFTR functional expression at the apical PM in human CF bronchial epithelia. Although knockdown of RPL12, a component of the ribosomal stalk, attenuated the translational elongation rate, it increased the folding efficiency as well as the conformational stability of the ΔF508-CFTR, manifesting in 3-fold augmented PM density and function of the mutant. Combination of RPL12 knockdown with the corrector drug, VX-809 (lumacaftor) restored the mutant function to ~50% of the wild-type channel in primary CFTRΔF508/ΔF508 human bronchial epithelia. These results and the observation that silencing of other ribosomal stalk proteins partially rescue the loss-of-function phenotype of ΔF508-CFTR suggest that the ribosomal stalk modulates the folding efficiency of the mutant and is a potential therapeutic target for correction of the ΔF508-CFTR folding defect. PMID:27168400

  1. Ribosomal Stalk Protein Silencing Partially Corrects the ΔF508-CFTR Functional Expression Defect.

    Directory of Open Access Journals (Sweden)

    Guido Veit

    2016-05-01

    Full Text Available The most common cystic fibrosis (CF causing mutation, deletion of phenylalanine 508 (ΔF508 or Phe508del, results in functional expression defect of the CF transmembrane conductance regulator (CFTR at the apical plasma membrane (PM of secretory epithelia, which is attributed to the degradation of the misfolded channel at the endoplasmic reticulum (ER. Deletion of phenylalanine 670 (ΔF670 in the yeast oligomycin resistance 1 gene (YOR1, an ABC transporter of Saccharomyces cerevisiae phenocopies the ΔF508-CFTR folding and trafficking defects. Genome-wide phenotypic (phenomic analysis of the Yor1-ΔF670 biogenesis identified several modifier genes of mRNA processing and translation, which conferred oligomycin resistance to yeast. Silencing of orthologues of these candidate genes enhanced the ΔF508-CFTR functional expression at the apical PM in human CF bronchial epithelia. Although knockdown of RPL12, a component of the ribosomal stalk, attenuated the translational elongation rate, it increased the folding efficiency as well as the conformational stability of the ΔF508-CFTR, manifesting in 3-fold augmented PM density and function of the mutant. Combination of RPL12 knockdown with the corrector drug, VX-809 (lumacaftor restored the mutant function to ~50% of the wild-type channel in primary CFTRΔF508/ΔF508 human bronchial epithelia. These results and the observation that silencing of other ribosomal stalk proteins partially rescue the loss-of-function phenotype of ΔF508-CFTR suggest that the ribosomal stalk modulates the folding efficiency of the mutant and is a potential therapeutic target for correction of the ΔF508-CFTR folding defect.

  2. Identification of CFTR Gene Mutations in Chinese Patients with Congenital Obstructive Azoospermia

    Institute of Scientific and Technical Information of China (English)

    曾国华; 吴开俊; 梅骅; 庄广伦

    2001-01-01

    Objective To analyze the frequency and hot spot of CFTR gene mutations in Chinese patients with congenital obstructive azoospermia Materials & Methods Mutations in CFTR exon 2,3,4,5,6a,8,10,11,12,13,15A 17b, 19A,20,21and 23 were detected. PCR-single strand conformation poly-morphism (SSCP) and direct sequencing were performed on 32 patients with congenital bilateral absence of the vas deferens (CBAVD), 17 patients with congenital unilateral absence of the vas deferens (CUAVD) and 50 normal Chinese.Results No CFTR gene mutations were detected in 50 normal Chinese. One CBAVD patient exhibited an abnormal band on SSCP for exon 10 of the CFTR gene and subsequent DNA sequencing showed a 3 bp deletion at position 1 653~ 1 655, which caused the deletion of a single amino acid, phenyalanine, in codon 508, i. e. , △F 508. A shift mutation was detected in another CBAVD patient in exon 2, a 1 bp deletion at position 225, 225 delC. One CUAVD patient exhibited an abnormal band on SSCP for exon 17 b of CFTR gene. Subsequent DNA sequencing showed a C-to-A transversion at position 3 295, which led to a predicted change of Leusine (codon 1 055,CUU) to Isoleucine (codon AUU), L1055I.Conclusion CFTR mutation could be detected in Chinese patients with congenital obstructive azoospermia. But no hot spots of mutations are discovered. 225 delC and L1055I are identified as two novel mutations, which are found only in Chinese.

  3. Impact of Cystic Fibrosis Transmembrane Regulator (CFTR gene mutations on male infertility

    Directory of Open Access Journals (Sweden)

    Jlenia Elia

    2014-09-01

    Full Text Available Objective. The aim of this study was to evaluate the prevalence of most common mutations and intron 8 5T (IVS8-5T polymorphism of CFTR gene in Italian: a azoospermic males; b non azoospermic subjects, male partners of infertile couples enrolled in assisted reproductive technology (ART programs. Material and methods. We studied 242 subjects attending our Andrology Unit (44 azoospermic subjects and 198 non azoospermic subjects, male partners of infertile couples enrolled in ART programs. Semen analysis, molecular analysis for CFTR gene mutations and genomic variant of IVS8-5T polymorphic tract, karyotype and chromosome Y microdeletions, hormonal profile (LH, FSH, Testosterone and seminal biochemical markers (fructose, citric acid and L-carnitine were carried out. Results. The prevalence of the common CFTR mutations and/or the IVS8-5T polymorphism was 12.9% (4/31 cases in secretory azoospermia, while in obstructive azoospermia was 84.6% (11/13 cases; in these, the most frequent mutations were the F508del, R117H and W1282X. Regarding the non azoospermic subjects, the prevalence of the CFTR and/or the IVS8-5T polymorphism was 11.1% (11/99 cases in severe dyspermia, 8.1% (6/74 cases in moderate dyspermia and finally 4.0% (1/25 cases in normospermic subjects. Conclusions. This study confirms the highly significant prevalence of CFTR mutations in males with bilateral absence of the vas deferens or ejaculatory ducts obstruction compared with subjects with secretory azoospermia. Moreover, the significant prevalence of mutations in severely dyspermic subjects may suggest the possible involvement of CFTR even in the spermatogenic process. This could explain the unsatisfactory recovery of sperm from testicular fine needle aspiration in patients affected by genital tract blockage.

  4. Small-molecule CFTR activators increase tear secretion and prevent experimental dry eye disease.

    Science.gov (United States)

    Flores, Alyssa M; Casey, Scott D; Felix, Christian M; Phuan, Puay W; Verkman, A S; Levin, Marc H

    2016-05-01

    Dry eye disorders, including Sjögren's syndrome, constitute a common problem in the aging population, with limited effective therapeutic options available. The cAMP-activated Cl(-) channel cystic fibrosis transmembrane conductance regulator (CFTR) is a major prosecretory channel at the ocular surface. We investigated whether compounds that target CFTR can correct the abnormal tear film in dry eye. Small-molecule activators of human wild-type CFTR identified by high-throughput screening were evaluated in cell culture and in vivo assays, to select compounds that stimulate Cl(-)-driven fluid secretion across the ocular surface in mice. An aminophenyl-1,3,5-triazine, CFTRact-K089, fully activated CFTR in cell cultures with EC50 ∼250 nM and produced an ∼8.5 mV hyperpolarization in ocular surface potential difference. When delivered topically, CFTRact-K089 doubled basal tear volume for 4 h and had no effect in CF mice. CFTRact-K089 showed sustained tear film bioavailability without detectable systemic absorption. In a mouse model of aqueous-deficient dry eye produced by lacrimal ablation, topical administration of 0.1 nmol CFTRact-K089 3 times daily restored tear volume to basal levels, preventing corneal epithelial disruption when initiated at the time of surgery and reversing it when started after development of dry eye. Our results support the potential utility of CFTR-targeted activators as a novel prosecretory treatment for dry eye.-Flores, A. M., Casey, S. D., Felix, C. M., Phuan, P. W., Verkman, A. S., Levin, M. H. Small-molecule CFTR activators increase tear secretion and prevent experimental dry eye disease. PMID:26842854

  5. Regulated trafficking of the CFTR chloride channel

    NARCIS (Netherlands)

    Braakman, L.J.; Kleizen, B.; Jonge, H.R. de

    2000-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR), the ABC transporter encoded by the cystic fibrosis gene, is localized in the apical membrane of epithelial cells where it functions as a cyclic AMP-regulated chloride channel and as a regulator of other ion channels and transporters. Wh

  6. The zebrafish Kupffer's vesicle as a model system for the molecular mechanisms by which the lack of Polycystin-2 leads to stimulation of CFTR

    Directory of Open Access Journals (Sweden)

    Mónica Roxo-Rosa

    2015-11-01

    Full Text Available In autosomal dominant polycystic kidney disease (ADPKD, cyst inflation and continuous enlargement are associated with marked transepithelial ion and fluid secretion into the cyst lumen via cystic fibrosis transmembrane conductance regulator (CFTR. Indeed, the inhibition or degradation of CFTR prevents the fluid accumulation within cysts. The in vivo mechanisms by which the lack of Polycystin-2 leads to CFTR stimulation are an outstanding challenge in ADPKD research and may bring important biomarkers for the disease. However, hampering their study, the available ADPKD in vitro cellular models lack the three-dimensional architecture of renal cysts and the ADPKD mouse models offer limited access for live-imaging experiments in embryonic kidneys. Here, we tested the zebrafish Kupffer's vesicle (KV as an alternative model-organ. KV is a fluid-filled vesicular organ, lined by epithelial cells that express both CFTR and Polycystin-2 endogenously, being each of them easily knocked-down. Our data on the intracellular distribution of Polycystin-2 support its involvement in the KV fluid-flow induced Ca2+-signalling. Mirroring kidney cysts, the KV lumen inflation is dependent on CFTR activity and, as we clearly show, the knockdown of Polycystin-2 results in larger KV lumens through overstimulation of CFTR. In conclusion, we propose the zebrafish KV as a model organ to study the renal cyst inflation. Favouring its use, KV volume can be easily determined by in vivo imaging offering a live readout for screening compounds and genes that may prevent cyst enlargement through CFTR inhibition.

  7. Development of rAAV2-CFTR: History of the First rAAV Vector Product to be Used in Humans.

    Science.gov (United States)

    Loring, Heather S; ElMallah, Mai K; Flotte, Terence R

    2016-04-01

    The first human gene therapy trials using recombinant adeno-associated virus (rAAV) vectors were performed in cystic fibrosis (CF) patients. Over 100 CF patients were enrolled in 5 separate trials of rAAV2-CFTR administration via nasal, endobronchial, maxillary sinus, and aerosol delivery. Recombinant AAV vectors were designed to deliver the CF transmembrane regulator (CFTR) gene and correct the basic CFTR defect by restoring chloride transport and reverting the upregulation of proinflammatory cytokines. However, vector DNA expression was limited in duration because of the low incidence of integration and natural airway epithelium turnover. In addition, repeated administration of AAV-CFTR vector resulted in a humoral immune response that prevented effective gene transfer from subsequent doses of vector. AAV serotype 2 was used in human trials before the comparison with other serotypes and determination that serotypes 1 and 5 not only possess higher tropism for the airway epithelium, but also are capable of bypassing the binding and trafficking processes-both were important hindrances to the effectiveness of rAAV2. Although rAAV-CFTR gene therapy does not appear likely to supplant newer small-molecule CFTR modulators in the near future, early work with rAAV-CFTR provided an important foundation for later use of rAAV in humans. PMID:26895204

  8. Depleted uranium

    International Nuclear Information System (INIS)

    Full text: The Director General of the International Atomic Energy Agency (IAEA), Mohamed ElBaradei, issued today the following statement: The IAEA has been involved in United Nations efforts relating to the impact of the use of depleted uranium (DU) ammunition in Kosovo. It has supported the United Nations Environment Programme (UNEP) in the assessment which it is making, at the request of the Secretary-General, of that impact. In this connection, in November 2000, Agency experts participated in a UNEP-led fact-finding mission in Kosovo. DU is only slightly radioactive, being about 40% as radioactive as natural uranium. Chemically and physically, DU behaves in the same way as natural uranium. The chemical toxicity is normally the dominant factor for human health. However, it is necessary to carefully assess the impact of DU in the special circumstances in which it was used, e.g. to determine whether it was inhaled or ingested or whether fragments came into close contact with individuals. It is therefore essential, before an authoritative conclusion can be reached, that a detailed survey of the territory in which DU was used and of the people who came in contact with the depleted uranium in any form be carried out. In the meantime it would be prudent, as recommended by the leader of the November UNEP mission, to adopt precautionary measures. Depending on the results of the survey further measures may be necessary. The Agency, within its statutory responsibilities and on the basis of internationally accepted radiation safety standards, will continue to co-operate with other organizations, in particular WHO and UNEP, with a view to carrying out a comprehensive assessment. Co-operation by and additional information from NATO will be prerequisites. The experience gained from such an assessment could be useful for similar studies that may be carried out elsewhere in the Balkans or in the Gulf. (author)

  9. Agricultural production and groundwater depletion under climate variability in India - Results from a regional scale crop modeling approach

    Science.gov (United States)

    Siegfried, T. U.; Sobolowski, S.; Fishman, R.; Vasquez, V.; Raj, P.; Narula, K. K.; Modi, V.; Lall, U.

    2009-12-01

    In India, recent declines in national food security may point to systemic deficiencies of agricultural production. Over the past decade and in the face of declining public investments in irrigation projects, the growth of production has increasingly become reliant on the allocation of large volumes of groundwater in an unsustainable manner. As a result, shallow as well as deep fossil groundwater resources are increasingly depleted and the buffer that mitigates negative impacts on production in case of Monsoonal dry-spells / drought conditions is lost. In the face of future climate and food supply uncertainty, it is vital that the connections between climate variability, unsustainable irrigation practices and their impacts on regional scale agricultural production be quantified and better understood. In our analysis, we focus on rice production in the Telengana region in Andhra Pradesh, which is characterized by a semi-arid tropical climate that is driven by the bimodal seasonality of the south-western monsoon. Traditionally, agricultural production of rice was constrained by precipitation variations during the wet season (Kharif). However, the advent of inexpensive pump technology in the 1970's, coupled with governmentally subsidized electricity has allowed year-round rice production. Thus, the Monsoon rains must not only drive wet season production but must also sufficiently recharge groundwater in order to support dry season production. Observed Production time series are characterized by non-stationarity and heteroscedasticity. Using a subset of eight districts, a non-linear Gaussian Process regression model is developed and yearly crop production is modeled at the district level over 48 years. We show that interannual climate variations, in the form of the monsoon rains, play a significant role in determining the area of land set aside for dry season planting and thus affect total yearly production. The results suggest that a non-linear Bayesian regression

  10. Molecular Motors and Apical CFTR Traffic in Epithelia

    Directory of Open Access Journals (Sweden)

    Dmitri V. Kravtsov

    2013-05-01

    Full Text Available Intracellular protein traffic plays an important role in the regulation of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR chloride channels. Microtubule and actin-based motor proteins direct CFTR movement along trafficking pathways. As shown for other regulatory proteins such as adaptors, the involvement of protein motors in CFTR traffic is cell-type specific. Understanding motor specificity provides insight into the biology of the channel and opens opportunity for discovery of organ-specific drug targets for treating CFTR-mediated diseases.

  11. Divergent signaling via SUMO modification: potential for CFTR modulation.

    Science.gov (United States)

    Ahner, Annette; Gong, Xiaoyan; Frizzell, Raymond A

    2016-02-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) is generally responsible for the cAMP/PKA regulated anion conductance at the apical membranes of secretory epithelial cells. Mutations in CFTR underlie cystic fibrosis (CF), in which the most common variant, F508del, causes protein misfolding and its proteasome-mediated degradation. A new pathway that contributes to mutant CFTR degradation is mediated by the small heat shock protein, Hsp27, which cooperates with Ubc9, the E2 enzyme for SUMOylation, to selectively conjugate mutant CFTR with SUMO-2/3. This SUMO paralog can form polychains, which are recognized by the ubiquitin E3 enzyme, RNF4, leading to CFTR ubiquitylation and recognition by the proteasome. We found also that F508del CFTR could be modified by SUMO-1, a paralog that does not support SUMO polychain formation. The use of different SUMO paralogs to modify and target a single substrate for divergent purposes is not uncommon. In this short review we discuss the possibility that conjugation with SUMO-1 could protect mutant CFTR from disposal by RNF4 and similar ubiquitin ligases. We hypothesize that such a pathway could contribute to therapeutic efforts to stabilize immature mutant CFTR and thereby enhance the action of therapeutics that correct CFTR trafficking to the apical membranes. PMID:26582473

  12. Targeted Integration of a Super-Exon into the CFTR Locus Leads to Functional Correction of a Cystic Fibrosis Cell Line Model.

    Science.gov (United States)

    Bednarski, Christien; Tomczak, Katja; Vom Hövel, Beate; Weber, Wolf-Michael; Cathomen, Toni

    2016-01-01

    In vitro disease models have enabled insights into the pathophysiology of human disease as well as the functional evaluation of new therapies, such as novel genome engineering strategies. In the context of cystic fibrosis (CF), various cellular disease models have been established in recent years, including organoids based on induced pluripotent stem cell technology that allowed for functional readouts of CFTR activity. Yet, many of these in vitro CF models require complex and expensive culturing protocols that are difficult to implement and may not be amenable for high throughput screens. Here, we show that a simple cellular CF disease model based on the bronchial epithelial ΔF508 cell line CFBE41o- can be used to validate functional CFTR correction. We used an engineered nuclease to target the integration of a super-exon, encompassing the sequences of CFTR exons 11 to 27, into exon 11 and re-activated endogenous CFTR expression by treating CFBE41o- cells with a demethylating agent. We demonstrate that the integration of this super-exon resulted in expression of a corrected mRNA from the endogenous CFTR promoter and used short-circuit current measurements in Ussing chambers to corroborate restored ion transport of the repaired CFTR channels. In conclusion, this study proves that the targeted integration of a large super-exon in CFTR exon 11 leads to functional correction of CFTR, suggesting that this strategy can be used to functionally correct all CFTR mutations located downstream of the 5' end of exon 11. PMID:27526025

  13. Cytoplasmic pathway followed by chloride ions to enter the CFTR channel pore.

    Science.gov (United States)

    El Hiani, Yassine; Negoda, Alexander; Linsdell, Paul

    2016-05-01

    Most ATP-binding cassette (ABC) proteins function as ATP-dependent membrane pumps. One exception is the cystic fibrosis transmembrane conductance regulator (CFTR), an ABC protein that functions as a Cl(-) ion channel. As such, the CFTR protein must form a continuous pathway for the movement of Cl(-) ions from the cytoplasm to the extracellular solution when in its open channel state. Extensive functional investigations have characterized most parts of this Cl(-) permeation pathway. However, one region remains unexplored-the pathway connecting the cytoplasm to the membrane-spanning pore. We used patch clamp recording and extensive substituted cysteine accessibility mutagenesis to identify amino acid side-chains in cytoplasmic regions of CFTR that lie close to the pathway taken by Cl(-) ions as they pass from the cytoplasm through this pathway. Our results suggest that Cl(-) ions enter the permeation pathway via a single lateral tunnel formed by the cytoplasmic parts of the protein, and then follow a fairly direct central pathway towards the membrane-spanning parts of the protein. However, this pathway is not lined continuously by any particular part of the protein; instead, the contributions of different cytoplasmic regions of the protein appear to change as the permeation pathway approaches the membrane, which appears to reflect the ways in which different cytoplasmic regions of the protein are oriented towards its central axis. Our results allow us to define for the first time the complete Cl(-) permeation pathway in CFTR, from the cytoplasm to the extracellular solution. PMID:26659082

  14. CFTR mutations have no effect on results of ICSI in congenital obstructive azoospermia patients%CFTR突变基因l不影响先天性梗阻性无精子症患者ICSI治疗的成功率

    Institute of Scientific and Technical Information of China (English)

    曾国华; 吴开俊; 梅骅; 庄广伦

    2001-01-01

    为探讨囊性纤维化跨膜转运调节物(Cystic Fibrosis Transmembrane Conductance Regulator,CFTR)基因突变是否影响先天性梗阻性无精子症患者单精子卵浆内注射(Intracytoplasmic Sperm Injection,ICSI)治疗的成功率,本文对3例先天性梗阻性无精子症CFTR突变基因携带者和18例CFTR突变基因非携带者进行了ICSI的治疗.结果表明:先天性梗阻性无精子症CFTR突变基因携带者与CFIR突变基因非携带者ICSI治疗时受精率、卵裂率和妊娠率无显著性差异.结论:CFTR突变基因并不影响先天性梗阻性无精子症患者ICSI治疗的成功率,故这些患者在ICSI治疗前夫妻双方更有必要行CFTR突变基因的筛查.

  15. Mutation Analysis of CFTR Gene in 70 Iranian Cystic Fibrosis Patients

    Directory of Open Access Journals (Sweden)

    Reza Alibakhshi Mahdi Zamani

    2006-03-01

    Full Text Available Cystic fibrosis (CF is the most common inherited disorder in Caucasian populations, with over 1400 cystic fibrosis transmembrane conductance regulator (CFTR mutations. The type of mutations and their distributions varies widely between different countries and/or ethnic groups. Seventy Iranian cystic fibrosis patients were screened for the CFTR gene mutation using ARMS/PCR (amplification refractory mutation system for the following mutations: ∆F508, N1303K, G542X, 1717-1G>A, R553X, W1282X, G551D, 621+1G>T, ∆I507 and R560T. Single strand conformation polymorphism (SSCP analysis of exons 3, 7, 10, 11 and 17b, including both the exon/intron junctions, of the CFTR gene was performed in patients in whom no mutation could be identified on one or both CFTR genes. As a result of this screening, only three mutations were found: ∆F508 mutation was found in 25 (17.8% alleles, N1303K in six (4.3% alleles and G542X in five (3.6% alleles. Thus, a total of 3 mutations cover 25.7% of CF alleles. These finding will be used for planning future screening and appropriate genetic counseling programs in Iranian CF patients.

  16. Analysis of mutations in the cystic fibrosis transmembrane regulator (CFTR gene in patients with obstructive azoospermia

    Directory of Open Access Journals (Sweden)

    Andrea L.F. Bernardino

    2003-01-01

    Full Text Available Congenital bilateral absence of the vas deferens (CBAVD accounts for 1%-2% of sterility in men. A high incidence of mutations, as well as the involvement of the 5T variant of the T tract length in intron 8 of the cystic fibrosis conductance regulator (CFTR gene, have been previously described in males with CBAVD. Herein we report the screening for mutations and for the 5T variant of the CFTR gene in 17 patients with CBAVD and three others with non-CABVD obstructive azoospermia. In the CBAVD group, three patients (15% were compound heterozygotes for mutations, and five patients (25% had a mutation in one allele and the 5T variant in the other; the 5T variant was also present in two other patients, one of them being homozygous. The most frequent mutation was DF508, present on five chromosomes (12.5%. A novel missense mutation (A399D was detected in a Japanese CBVAD patient. Our results yield further evidence for a strong association between male obstructive azoospermia caused by CBAVD and mutation/5T variant in the CFTR gene. The search for CFTR mutations in such patients is thus recommended for genetic counseling of couples who undergo assisted fertilization due to CBAVD.

  17. Experimental results of hydrogen distillation at the low power cryogenic column for the production of deuterium depleted hydrogen

    International Nuclear Information System (INIS)

    The Deuterium Removal Unit (DRU) has been designed and built at the Petersburg Nuclear Physics Inst. (PNPI) to produce isotopically pure hydrogen with deuterium content less than 1 ppm. The cryogenic distillation column of 2.2 cm inner diameter and 155 cm packing height is the main element of the DRU. Column performances at different hydrogen distillation operating modes have been measured. The height equivalent to theoretical plate (HETP) for the column is 2.2 cm and almost constant over a wide range of vapour flow rates. Deuterium depleted hydrogen with a deuterium content of less than 0.1 ppm was produced in required quantity. (authors)

  18. Management of depleted uranium

    International Nuclear Information System (INIS)

    Large stocks of depleted uranium have arisen as a result of enrichment operations, especially in the United States and the Russian Federation. Countries with depleted uranium stocks are interested in assessing strategies for the use and management of depleted uranium. The choice of strategy depends on several factors, including government and business policy, alternative uses available, the economic value of the material, regulatory aspects and disposal options, and international market developments in the nuclear fuel cycle. This report presents the results of a depleted uranium study conducted by an expert group organised jointly by the OECD Nuclear Energy Agency and the International Atomic Energy Agency. It contains information on current inventories of depleted uranium, potential future arisings, long term management alternatives, peaceful use options and country programmes. In addition, it explores ideas for international collaboration and identifies key issues for governments and policy makers to consider. (authors)

  19. Phosphatase inhibitors activate normal and defective CFTR chloride channels.

    OpenAIRE

    Becq, F; Jensen, T J; Chang, X B; Savoia, A.; Rommens, J M; Tsui, L C; Buchwald, M; Riordan, J R; Hanrahan, J W

    1994-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel is regulated by phosphorylation and dephosphorylation at multiple sites. Although activation by protein kinases has been studied in some detail, the dephosphorylation step has received little attention. This report examines the mechanisms responsible for the dephosphorylation and spontaneous deactivation ("rundown") of CFTR chloride channels excised from transfected Chinese hamster ovary (CHO) and human airway epi...

  20. MARCH2 regulates autophagy by promoting CFTR ubiquitination and degradation and PIK3CA-AKT-MTOR signaling.

    Science.gov (United States)

    Xia, Dan; Qu, Liujing; Li, Ge; Hongdu, Beiqi; Xu, Chentong; Lin, Xin; Lou, Yaxin; He, Qihua; Ma, Dalong; Chen, Yingyu

    2016-09-01

    MARCH2 (membrane-associated RING-CH protein 2), an E3 ubiquitin ligase, is mainly associated with the vesicle trafficking. In the present study, for the first time, we demonstrated that MARCH2 negatively regulates autophagy. Our data indicated that overexpression of MARCH2 impaired autophagy, as evidenced by attenuated levels of LC3B-II and impaired degradation of endogenous and exogenous autophagic substrates. By contrast, loss of MARCH2 expression had the opposite effects. In vivo experiments demonstrate that MARCH2 knockout mediated autophagy results in an inhibition of tumorigenicity. Further investigation revealed that the induction of autophagy by MARCH2 deficiency was mediated through the PIK3CA-AKT-MTOR signaling pathway. Additionally, we found that MARCH2 interacts with CFTR (cystic fibrosis transmembrane conductance regulator), promotes the ubiquitination and degradation of CFTR, and inhibits CFTR-mediated autophagy in tumor cells. The functional PDZ domain of MARCH2 is required for the association with CFTR. Thus, our study identified a novel negative regulator of autophagy and suggested that the physical and functional connection between the MARCH2 and CFTR in different conditions will be elucidated in the further experiments. PMID:27308891

  1. Burn-up credit criticality benchmark. Phase 4-B: results and analysis of MOX fuel depletion calculations

    International Nuclear Information System (INIS)

    The DECD/NEA Expert Group on Burn-up Credit was established in 1991 to address scientific and technical issues connected with the use of burn-up credit in nuclear fuel cycle operations. Following the completion of six benchmark exercises with uranium oxide (UOX) fuels irradiated in pressurised water reactors (PWRs) and boiling water reactors (BWRs), the present report concerns mixed uranium and plutonium oxide (MOX) fuels irradiated in PWRs. The exercises consisted of inventory calculations of MOX fuels for two initial plutonium compositions. The depletion calculations were carried out using three representations of the MOX assemblies and their interface with UOX assemblies. This enabled the investigation of the spatial and spectral effects during the irradiation of the MOX fuels. (author)

  2. An unexpected effect of TNF-α on F508del-CFTR maturation and function [v1; ref status: indexed, http://f1000r.es/5jf

    Directory of Open Access Journals (Sweden)

    Sara Bitam

    2015-07-01

    Full Text Available Cystic fibrosis (CF is a multifactorial disease caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR, which encodes a cAMP-dependent Cl- channel. The most frequent mutation, F508del, leads to the synthesis of a prematurely degraded, otherwise partially functional protein. CFTR is expressed in many epithelia, with major consequences in the airways of patients with CF, characterized by both fluid transport abnormalities and persistent inflammatory responses. The relationship between the acute phase of inflammation and the expression of wild type (WT CFTR or F508del-CFTR is poorly understood. The aim of the present study was to investigate this effect. The results show that 10 min exposure to TNF-alpha (0.5-50ng/ml of F508del-CFTR-transfected HeLa cells and human bronchial cells expressing F508del-CFTR in primary culture (HBE leads to the maturation of F508del-CFTR and induces CFTR chloride currents. The enhanced CFTR expression and function upon TNFα is sustained, in HBE cells, for at least 24 h. The underlying mechanism of action involves a protein kinase C (PKC signaling pathway, and occurs through insertion of vesicles containing F508del-CFTR to the plasma membrane, with TNFα behaving as a corrector molecule. In conclusion, a novel and unexpected action of TNFα has been discovered and points to the importance of systematic studies on the roles of inflammatory mediators in the maturation of abnormally folded proteins in general and in the context of CF in particular.

  3. An unexpected effect of TNF-α on F508del-CFTR maturation and function [v2; ref status: indexed, http://f1000r.es/5tv

    Directory of Open Access Journals (Sweden)

    Sara Bitam

    2015-09-01

    Full Text Available Cystic fibrosis (CF is a multifactorial disease caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR, which encodes a cAMP-dependent Cl- channel. The most frequent mutation, F508del, leads to the synthesis of a prematurely degraded, otherwise partially functional protein. CFTR is expressed in many epithelia, with major consequences in the airways of patients with CF, characterized by both fluid transport abnormalities and persistent inflammatory responses. The relationship between the acute phase of inflammation and the expression of wild type (WT CFTR or F508del-CFTR is poorly understood. The aim of the present study was to investigate this effect. The results show that 10 min exposure to TNF-alpha (0.5-50ng/ml of F508del-CFTR-transfected HeLa cells and human bronchial cells expressing F508del-CFTR in primary culture (HBE leads to the maturation of F508del-CFTR and induces CFTR chloride currents. The enhanced CFTR expression and function upon TNFα is sustained, in HBE cells, for at least 24 h. The underlying mechanism of action involves a protein kinase C (PKC signaling pathway, and occurs through insertion of vesicles containing F508del-CFTR to the plasma membrane, with TNFα behaving as a corrector molecule. In conclusion, a novel and unexpected action of TNFα has been discovered and points to the importance of systematic studies on the roles of inflammatory mediators in the maturation of abnormally folded proteins in general and in the context of CF in particular.

  4. The Mitochondrial Complex I Activity Is Reduced in Cells with Impaired Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Function

    OpenAIRE

    Valdivieso, Angel G.; Clauzure, Mariángeles; Marín, María C.; Taminelli, Guillermo L.; Massip Copiz, María M.; Sánchez, Francisco; Schulman, Gustavo; Teiber, María L.; Santa-Coloma, Tomás A.

    2012-01-01

    Cystic fibrosis (CF) is a frequent and lethal autosomal recessive disease. It results from different possible mutations in the CFTR gene, which encodes the CFTR chloride channel. We have previously studied the differential expression of genes in CF and CF corrected cell lines, and found a reduced expression of MTND4 in CF cells. MTND4 is a mitochondrial gene encoding the MTND4 subunit of the mitochondrial Complex I (mCx-I). Since this subunit is essential for the assembly and activity of mCx-...

  5. Nasal Potential Difference in Cystic Fibrosis considering Severe CFTR Mutations

    OpenAIRE

    2015-01-01

    The gold standard for diagnosing cystic fibrosis (CF) is a sweat chloride value above 60 mEq/L. However, this historical and important tool has limitations; other techniques should be studied, including the nasal potential difference (NPD) test. CFTR gene sequencing can identify CFTR mutations, but this method is time-consuming and too expensive to be used in all CF centers. The present study compared CF patients with two classes I-III CFTR mutations (10 patients) (G1), CF patients with class...

  6. Expression of TRPC3 in Chinese Hamster Ovary Cells Results in Calcium-activated Cation Currents Not Related to Store Depletion

    OpenAIRE

    Zitt, Christof; Obukhov, Alexander G.; Strübing, Carsten; Zobel, Andrea; Kalkbrenner, Frank; Lückhoff, Andreas; Schultz, Günter

    1997-01-01

    TRPC3 (or Htrp3) is a human member of the trp family of Ca2+-permeable cation channels. Since expression of TRPC3 cDNA results in markedly enhanced Ca2+ influx in response to stimulation of membrane receptors linked to phospholipase C (Zhu, X., J. Meisheng, M. Peyton, G. Bouley, R. Hurst, E. Stefani, and L. Birnbaumer. 1996. Cell. 85:661–671), we tested whether TRPC3 might represent a Ca2+ entry pathway activated as a consequence of depletion of intracellular calcium stores. CHO cells express...

  7. Regulatory crosstalk by protein kinases on CFTR trafficking and activity

    Science.gov (United States)

    Farinha, Carlos Miguel; Swiatecka-Urban, Agnieszka; Brautigan, David; Jordan, Peter

    2016-01-01

    Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) is a member of the ATP binding cassette (ABC) transporter superfamily that functions as a cAMP-activated chloride ion channel in fluid-transporting epithelia. There is abundant evidence that CFTR activity (i.e. channel opening and closing) is regulated by protein kinases and phosphatases via phosphorylation and dephosphorylation. Here, we review recent evidence for the role of protein kinases in regulation of CFTR delivery to and retention in the plasma membrane. We review this information in a broader context of regulation of other transporters by protein kinases because the overall functional output of transporters involves the integrated control of both their number at the plasma membrane and their specific activity. While many details of the regulation of intracellular distribution of CFTR and other transporters remain to be elucidated, we hope that this review will motivate research providing new insights into how protein kinases control membrane transport to impact health and disease.

  8. Assessing the Disease-Liability of Mutations in CFTR

    OpenAIRE

    Ferec, Claude; Cutting, Garry R

    2012-01-01

    Over 1900 mutations have been reported in the cystic fibrosis transmembrane conductance regulator (CFTR), the gene defective in patients with cystic fibrosis. These mutations have been discovered primarily in individuals who have features consistent with the diagnosis of CF. In some cases, it has been recognized that the mutations are not causative of cystic fibrosis but are responsible for disorders with features similar to CF, and these conditions have been termed CFTR-related disorders or ...

  9. Rescue of Murine F508del CFTR Activity in Native Intestine by Low Temperature and Proteasome Inhibitors

    NARCIS (Netherlands)

    M. Wilke (Martina); A.G. Bot (Alice); H. Jorna (Huub); B.J. Scholte (Bob); H.R. de Jonge (Hugo)

    2012-01-01

    textabstractMost patients with Cystic Fibrosis (CF) carry at least one allele with the F508del mutation, resulting in a CFTR chloride channel protein with a processing, gating and stability defect, but with substantial residual activity when correctly sorted to the apical membranes of epithelial cel

  10. Development of allele-specific multiplex PCR to determine the length of poly-T in intron 8 of CFTR

    Directory of Open Access Journals (Sweden)

    Neng Chen

    2014-07-01

    Full Text Available Cystic fibrosis transmembrane conductance regulator (CFTR gene mutation analysis has been implemented for Cystic Fibrosis (CF carrier screening, and molecular diagnosis of CF and congenital bilateral absence of the vas deferens (CBAVD. Although poly-T allele analysis in intron 8 of CFTR is required when a patient is positive for R117H, it is not recommended for routine carrier screening. Therefore, commercial kits for CFTR mutation analysis were designed either to mask the poly-T allele results, unless a patient is R117H positive, or to have the poly-T analysis as a standalone reflex test using the same commercial platform. There are other standalone assays developed to detect poly-T alleles, such as heteroduplex analysis, High Resolution Melting (HRM curve analysis, allele-specific PCR (AS-PCR and Sanger sequencing. In this report, we developed a simple and easy-to-implement multiplex AS-PCR assay using unlabeled standard length primers, which can be used as a reflex or standalone test for CFTR poly-T track analysis. Out of 115 human gDNA samples tested, results from our new AS-PCR matched to the previous known poly-T results or results from Sanger sequencing.

  11. Targeted therapies to improve CFTR function in cystic fibrosis.

    Science.gov (United States)

    Brodlie, Malcolm; Haq, Iram J; Roberts, Katie; Elborn, J Stuart

    2015-01-01

    Cystic fibrosis is the most common genetically determined, life-limiting disorder in populations of European ancestry. The genetic basis of cystic fibrosis is well established to be mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene that codes for an apical membrane chloride channel principally expressed by epithelial cells. Conventional approaches to cystic fibrosis care involve a heavy daily burden of supportive treatments to combat lung infection, help clear airway secretions and maintain nutritional status. In 2012, a new era of precision medicine in cystic fibrosis therapeutics began with the licensing of a small molecule, ivacaftor, which successfully targets the underlying defect and improves CFTR function in a subgroup of patients in a genotype-specific manner. Here, we review the three main targeted approaches that have been adopted to improve CFTR function: potentiators, which recover the function of CFTR at the apical surface of epithelial cells that is disrupted in class III and IV genetic mutations; correctors, which improve intracellular processing of CFTR, increasing surface expression, in class II mutations; and production correctors or read-through agents, which promote transcription of CFTR in class I mutations. The further development of such approaches offers great promise for future therapeutic strategies in cystic fibrosis. PMID:26403534

  12. Characterizing responses to CFTR-modulating drugs using rectal organoids derived from subjects with cystic fibrosis.

    Science.gov (United States)

    Dekkers, Johanna F; Berkers, Gitte; Kruisselbrink, Evelien; Vonk, Annelotte; de Jonge, Hugo R; Janssens, Hettie M; Bronsveld, Inez; van de Graaf, Eduard A; Nieuwenhuis, Edward E S; Houwen, Roderick H J; Vleggaar, Frank P; Escher, Johanna C; de Rijke, Yolanda B; Majoor, Christof J; Heijerman, Harry G M; de Winter-de Groot, Karin M; Clevers, Hans; van der Ent, Cornelis K; Beekman, Jeffrey M

    2016-06-22

    Identifying subjects with cystic fibrosis (CF) who may benefit from cystic fibrosis transmembrane conductance regulator (CFTR)-modulating drugs is time-consuming, costly, and especially challenging for individuals with rare uncharacterized CFTR mutations. We studied CFTR function and responses to two drugs-the prototypical CFTR potentiator VX-770 (ivacaftor/KALYDECO) and the CFTR corrector VX-809 (lumacaftor)-in organoid cultures derived from the rectal epithelia of subjects with CF, who expressed a broad range of CFTR mutations. We observed that CFTR residual function and responses to drug therapy depended on both the CFTR mutation and the genetic background of the subjects. In vitro drug responses in rectal organoids positively correlated with published outcome data from clinical trials with VX-809 and VX-770, allowing us to predict from preclinical data the potential for CF patients carrying rare CFTR mutations to respond to drug therapy. We demonstrated proof of principle by selecting two subjects expressing an uncharacterized rare CFTR genotype (G1249R/F508del) who showed clinical responses to treatment with ivacaftor and one subject (F508del/R347P) who showed a limited response to drug therapy both in vitro and in vivo. These data suggest that in vitro measurements of CFTR function in patient-derived rectal organoids may be useful for identifying subjects who would benefit from CFTR-correcting treatment, independent of their CFTR mutation. PMID:27334259

  13. Assessment of cystic fibrosis transmembrane conductance regulator (CFTR) activity in CFTR-null mice after bone marrow transplantation

    OpenAIRE

    Bruscia, Emanuela M.; Price, Joanna E.; Cheng, Ee-chun; Weiner, Scott; Caputo, Christina; Ferreira, Elisa C.; Egan, Marie E.; Krause, Diane S.

    2006-01-01

    Several studies have demonstrated that bone marrow (BM)-derived cells give rise to rare epithelial cells in the gastrointestinal (GI) and respiratory tracts after BM transplantation into myeloablated recipients. We investigate whether, after transplantation of cystic fibrosis transmembrane conductance regulator (CFTR)-positive BM-derived cells, BM-derived GI and airway epithelial cells can provide CFTR activity in the GI tract and nasal epithelium of recipient cystic fibrosis mice. CFTR−/− mi...

  14. Increased susceptibility of Cftr-/- mice to LPS-induced lung remodeling.

    Science.gov (United States)

    Bruscia, Emanuela M; Zhang, Ping-Xia; Barone, Christina; Scholte, Bob J; Homer, Robert; Krause, Diane S; Egan, Marie E

    2016-04-15

    Cystic fibrosis (CF) is caused by homozygous mutations of the CF transmembrane conductance regulator (CFTR) Cl(-) channel, which result in chronic pulmonary infection and inflammation, the major cause of morbidity and mortality. Although these processes are clearly related to each other, each is likely to contribute to the pathology differently. Understanding the contribution of each of these processes to the overall pathology has been difficult, because they are usually so intimately connected. Various CF mouse models have demonstrated abnormal immune responses compared with wild-type (WT) littermates when challenged with live bacteria or bacterial products acutely. However, these studies have not investigated the consequences of persistent inflammation on lung tissue in CF mice, which may better model the lung pathology in patients. We characterized the lung pathology and immune response of Cftr(-/-) (CF) and Cftr(+/+) (WT) mice to chronic administration of Pseudomonas aeruginosa lipopolysaccharide (LPS). We show that, after long-term repeated LPS exposure, CF mice develop an abnormal and persistent immune response, which is associated with more robust structural changes in the lung than those observed in WT mice. Although CF mice and their WT littermates develop lung pathology after chronic exposure to LPS, the inflammation and damage resolve in WT mice. However, CF mice do not recover efficiently, and, as a consequence of their chronic inflammation, CF mice are more susceptible to morphological changes and lung remodeling. This study shows that chronic inflammation alone contributes significantly to aspects of CF lung pathology. PMID:26851259

  15. Structure of wild type and mutant F508del CFTR: A small-angle X-ray scattering study of the protein-detergent complexes.

    Science.gov (United States)

    Pollock, Naomi L; Satriano, Letizia; Zegarra-Moran, Olga; Ford, Robert C; Moran, Oscar

    2016-04-01

    CFTR is an anionic channel expressed in epithelia whose mutations cause cystic fibrosis. Wild (WT) and mutated (F508del) types were over-expressed in yeast, solubilised in the detergent LPG-14 and purified. The detergent-CFTR complexes were studied by SAXS techniques using a solvent of variable density. The final result of the study is the numerical value of a set of parameters: molecular mass, volume and radius of gyration, average electron density and second moment of the electron density fluctuations inside the particles. It is also shown that in the complex the centres of gravity of CFTR and of the detergent are displaced relative to each other. The analysis of these parameters led to the determination of the size and shape of the volumes occupied by protein and by detergent in the complex. WT-CFTR to be an elongated molecule (maximum diameter ∼12.4nm) which spans a flat detergent micelle. The distance distribution function, P(r) confirms that the WT-CFTR is elongated and with an inhomogeneous electronic density. The F508del-CFTR molecule is also elongated (maximum diameter ∼13.2nm), but the associated detergent micelle hides a larger surface, plausibly related to an increased exposure of hydrophobic portions of the mutated protein. The corresponding P(r) is consistent with the presence of well defined domains, probably linked by flexible regions. These differences suggest that the full-length mutant F508del-CFTR has a detectably different conformation, in contrast to the minor differences observed for the isolated F508-containing domain. We interpret the data in terms of an incomplete post-translational assembly of the protein domains. PMID:26850167

  16. Physiological Adaptation of the Bacterium Lactococcus lactis in Response to the Production of Human CFTR

    NARCIS (Netherlands)

    Steen, Anton; Wiederhold, Elena; Gandhi, Tejas; Breitling, Rainer; Slotboom, Dirk Jan

    2011-01-01

    Biochemical and biophysical characterization of CFTR (the cystic fibrosis transmembrane conductance regulator) is thwarted by difficulties to obtain sufficient quantities of correctly folded and functional protein. Here we have produced human CFTR in the prokaryotic expression host Lactococcus lacti

  17. Comparative ex vivo, in vitro and in silico analyses of a CFTR splicing mutation: Importance of functional studies to establish disease liability of mutations.

    Science.gov (United States)

    Ramalho, Anabela S; Clarke, Luka A; Sousa, Marisa; Felicio, Verónica; Barreto, Celeste; Lopes, Carlos; Amaral, Margarida D

    2016-01-01

    The Cystic Fibrosis p.Ile1234Val missense mutation actually creates a new dual splicing site possibly used either as a new acceptor or donor. Here, we aimed to test the accuracy of in silico predictions by comparing them with in vitro and ex vivo functional analyses of this mutation for an accurate CF diagnosis/prognosis. To this end, we applied a new in vitro strategy using a CFTR mini-gene which includes the complete CFTR coding sequence plus intron 22 (short version) which allows the assessment of alternatively spliced mRNA levels as well as the properties of the resulting abnormal CFTR protein regarding processing, intracellular localization and function. Our data demonstrate that p.Ile1234Val leads to usage of the alternative splicing donor (but not acceptor) resulting in alternative CFTR transcripts lacking 18 nts of exon 22 which produce a truncated CFTR protein with residual Cl- channel function. These results recapitulate data from native tissues of a CF patient. In conclusion, the existing in silico prediction models have limited application and ex vivo functional assessment of mutation effects should be made. Alternatively the in vitro strategy adopted here can be applied to assess the disease liability of mutations for an accurate CF diagnosis/prognosis. PMID:25735457

  18. Characterizing responses to CFTR-modulating drugs using rectal organoids derived from subjects with cystic fibrosis

    NARCIS (Netherlands)

    Dekkers, Johanna F; Berkers, Gitte; Kruisselbrink, Evelien; Vonk, Annelotte; de Jonge, Hugo R; Janssens, Hettie M; Bronsveld, Inez; van de Graaf, Eduard A; Nieuwenhuis, Edward E S; Houwen, Roderick H J; Vleggaar, Frank P; Escher, Johanna C; de Rijke, Yolanda B; Majoor, Christof J; Heijerman, Harry G M; de Winter-de Groot, Karin M; Clevers, Hans; van der Ent, Cornelis K; Beekman, Jeffrey M

    2016-01-01

    Identifying subjects with cystic fibrosis (CF) who may benefit from cystic fibrosis transmembrane conductance regulator (CFTR)-modulating drugs is time-consuming, costly, and especially challenging for individuals with rare uncharacterized CFTR mutations. We studied CFTR function and responses to tw

  19. 21 CFR 866.5900 - Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system.

    Science.gov (United States)

    2010-04-01

    ... regulator (CFTR) gene mutation detection system. 866.5900 Section 866.5900 Food and Drugs FOOD AND DRUG... DEVICES Immunological Test Systems § 866.5900 Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system. (a) Identification. The CFTR gene mutation detection system is a...

  20. Differential expression of CFTR gene in the mouse intestinal tissues%CFTR 基因在小鼠肠道组织中的差异表达

    Institute of Scientific and Technical Information of China (English)

    王月影; 韩莹倩; 查光明; 汪新建; 李和平

    2014-01-01

    Object This experiment was conducted to study the relationship between CFTR gene expression in the intestinal tissues and secretory diarrhea.Methods Twenty-four Kunming mice were selected, half male and half female, and were randomly divided into 3 groups ( n=8 in each group):control group with intraperitoneal injection of 0.2 mL nor-mal saline, and the experimental group of mice by intraperitoneal injection of lipopolysaccharide(LPS) (6 mg/kg· bw). The mental state and intestinal morphology of the mice at 1 h and 8 h after LPS injection were observed to assess whether the secretory diarrhea model was successfully established.The expression of CFTR gene segments of intestine tissue was de-tected by fluorescence quantitative PCR.Results LPS induced secretory diarrhea.CFTR gene was expressed in the mouse duodenum, jejunum, ileum and colon tissues with different expression abundance.It was highest in the colon, but the difference was not significant between intestinal segments.Compared with the control group, LPS up-regulated the tran-scription level of CFTR gene in the duodenum, jejunum and ileum, and down-regulated the transcription of CFTR gene in the colon.Conclusions The results of our study suggest that the changes of the transcriptional level of CFTR gene are closely related with the diarrhea induced by LPS and the effects in different intestinal segments on the diarrhea is different. The jejunum plays a crucial role and the colon plays a least role in the Cl-secretion.%目的:研究肠道组织CFTR基因表达与分泌性腹泻发生的关系。方法选取KM小鼠24只,雌雄各半,随机分为3组(每组8只):对照组经小鼠腹腔注射0.2 mL生理盐水,实验组小鼠经腹腔注射LPS[6 mg/(kg· bw)]分别作用1 h、8 h,于注射后通过小鼠精神状态、肠道组织形态学判定分泌性腹泻模型的建立,利用荧光定量PCR法检测各段肠道组织CFTR基因的表达。结果 LPS成功诱导小鼠发生了分泌

  1. Rattlesnake Phospholipase A2 Increases CFTR-Chloride Channel Current and Corrects ∆F508CFTR Dysfunction: Impact in Cystic Fibrosis.

    Science.gov (United States)

    Faure, Grazyna; Bakouh, Naziha; Lourdel, Stéphane; Odolczyk, Norbert; Premchandar, Aiswarya; Servel, Nathalie; Hatton, Aurélie; Ostrowski, Maciej K; Xu, Haijin; Saul, Frederick A; Moquereau, Christelle; Bitam, Sara; Pranke, Iwona; Planelles, Gabrielle; Teulon, Jacques; Herrmann, Harald; Roldan, Ariel; Zielenkiewicz, Piotr; Dadlez, Michal; Lukacs, Gergely L; Sermet-Gaudelus, Isabelle; Ollero, Mario; Corringer, Pierre-Jean; Edelman, Aleksander

    2016-07-17

    Deletion of Phe508 in the nucleotide binding domain (∆F508-NBD1) of the cystic fibrosis transmembrane regulator (CFTR; a cyclic AMP-regulated chloride channel) is the most frequent mutation associated with cystic fibrosis. This mutation affects the maturation and gating of CFTR protein. The search for new high-affinity ligands of CFTR acting as dual modulators (correctors/activators) presents a major challenge in the pharmacology of cystic fibrosis. Snake venoms are a rich source of natural multifunctional proteins, potential binders of ion channels. In this study, we identified the CB subunit of crotoxin from Crotalus durissus terrificus as a new ligand and allosteric modulator of CFTR. We showed that CB interacts with NBD1 of both wild type and ∆F508CFTR and increases their chloride channel currents. The potentiating effect of CB on CFTR activity was demonstrated using electrophysiological techniques in Xenopus laevis oocytes, in CFTR-HeLa cells, and ex vivo in mouse colon tissue. The correcting effect of CB was shown by functional rescue of CFTR activity after 24-h ΔF508CFTR treatments with CB. Moreover, the presence of fully glycosylated CFTR was observed. Molecular docking allowed us to propose a model of the complex involving of the ABCβ and F1-like ATP-binding subdomains of ΔF508-NBD1. Hydrogen-deuterium exchange analysis confirmed stabilization in these regions, also showing allosteric stabilization in two other distal regions. Surface plasmon resonance competition studies showed that CB disrupts the ∆F508CFTR-cytokeratin 8 complex, allowing for the escape of ∆F508CFTR from degradation. Therefore CB, as a dual modulator of ΔF508CFTR, constitutes a template for the development of new anti-CF agents. PMID:27241308

  2. Oral fibrinogen-depleting agent lumbrokinase for secondary ischemic stroke prevention: results from a multicenter, randomized, parallel-group and controlled clinical trial

    Institute of Scientific and Technical Information of China (English)

    CAO Yong-jun; ZHANG Xia; WANG Wan-hua; ZHAI Wan-qing; QIAN Ju-fen; WANG Jian-sheng; CHEN Jun

    2013-01-01

    Background Elevated fibrinogen (Fg) level is a known risk factor for ischemic stroke.There are few clinical trials on oral fibrinogen-depleting therapies for secondary ischemic stroke prevention.We aimed to assess the effects of one-year therapy with oral lumbrokinase enteric-coated capsules on secondary ischemic stroke prevention.Methods This is a multicenter,randomized,parallel group and controlled study that began treatment in hospitalized patients with ischemic stroke and continued for 12 months.Patients were randomized to either the control group that received the standard stroke treatment or the fibrinogen-depleting group that received the standard stroke treatment plus enteric-coated lumbrokinase capsules.The NIH Stroke Scale scores (NIHSSs) and plasma Fg level were recorded.The carotid artery intima-media thickness (IMT) and status of plaques were examined through carotid ultrasound examination.Primary outcomes included all-cause mortality,any event of recurrent ischemic stroke/transient ischemic attack (TIA),hemorrhagic stroke,myocardial infarction and angina,and other noncerebral ischemia or hemorrhage.Kaplan-Meier survival analysis and the Long-rank test were used to compare total vascular end point incidence between the two groups.Comparison of median values between two groups was done by the Student t test,one-way analysis of variance (ANOVA),or non-parametric rank sum test.Results A total of 310 patients were enrolled,192 patients in the treatment group and 118 patients in the control group.Compared to the control group,the treatment group showed favorable outcomes in the Fg level,carotid IMT,the detection rate of vulnerable plaques,the volume of carotid plaques,NIHSS scores,and incidence of total vascular (6.78% and 2.08%,respectively) and cerebral vascular events (5.93% and 1.04%,respectively) (P <0.05).In the treatment group,the volume of carotid plaques was significantly related to the carotid IMT,the plaque diameter,width and number (P

  3. Steviol reduces MDCK Cyst formation and growth by inhibiting CFTR channel activity and promoting proteasome-mediated CFTR degradation.

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    Chaowalit Yuajit

    Full Text Available Cyst enlargement in polycystic kidney disease (PKD involves cAMP-activated proliferation of cyst-lining epithelial cells and transepithelial fluid secretion into the cyst lumen via cystic fibrosis transmembrane conductance regulator (CFTR chloride channel. This study aimed to investigate an inhibitory effect and detailed mechanisms of steviol and its derivatives on cyst growth using a cyst model in Madin-Darby canine kidney (MDCK cells. Among 4 steviol-related compounds tested, steviol was found to be the most potent at inhibiting MDCK cyst growth. Steviol inhibition of cyst growth was dose-dependent; steviol (100 microM reversibly inhibited cyst formation and cyst growth by 72.53.6% and 38.2±8.5%, respectively. Steviol at doses up to 200 microM had no effect on MDCK cell viability, proliferation and apoptosis. However, steviol acutely inhibited forskolin-stimulated apical chloride current in MDCK epithelia, measured with the Ussing chamber technique, in a dose-dependent manner. Prolonged treatment (24 h with steviol (100 microM also strongly inhibited forskolin-stimulated apical chloride current, in part by reducing CFTR protein expression in MDCK cells. Interestingly, proteasome inhibitor, MG-132, abolished the effect of steviol on CFTR protein expression. Immunofluorescence studies demonstrated that prolonged treatment (24 h with steviol (100 microM markedly reduced CFTR expression at the plasma membrane. Taken together, the data suggest that steviol retards MDCK cyst progression in two ways: first by directly inhibiting CFTR chloride channel activity and second by reducing CFTR expression, in part, by promoting proteasomal degradation of CFTR. Steviol and related compounds therefore represent drug candidates for treatment of polycystic kidney disease.

  4. Cystic fibrosis transmembrane conductance regulator (CFTR allelic variants relate to shifts in faecal microbiota of cystic fibrosis patients.

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    Serena Schippa

    Full Text Available INTRODUCTION: In this study we investigated the effects of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR gene variants on the composition of faecal microbiota, in patients affected by Cystic Fibrosis (CF. CFTR mutations (F508del is the most common lead to a decreased secretion of chloride/water, and to mucus sticky secretions, in pancreas, respiratory and gastrointestinal tracts. Intestinal manifestations are underestimated in CF, leading to ileum meconium at birth, or small bowel bacterial overgrowth in adult age. METHODS: Thirty-six CF patients, fasting and under no-antibiotic treatment, were CFTR genotyped on both alleles. Faecal samples were subjected to molecular microbial profiling through Temporal Temperature Gradient Electrophoresis and species-specific PCR. Ecological parameters and multivariate algorithms were employed to find out if CFTR variants could be related to the microbiota structure. RESULTS: Patients were classified by two different criteria: 1 presence/absence of F508del mutation; 2 disease severity in heterozygous and homozygous F508del patients. We found that homozygous-F508del and severe CF patients exhibited an enhanced dysbiotic faecal microbiota composition, even within the CF cohort itself, with higher biodiversity and evenness. We also found, by species-specific PCR, that potentially harmful species (Escherichia coli and Eubacterium biforme were abundant in homozygous-F508del and severe CF patients, while beneficial species (Faecalibacterium prausnitzii, Bifidobacterium spp., and Eubacterium limosum were reduced. CONCLUSIONS: This is the first report that establishes a link among CFTR variants and shifts in faecal microbiota, opening the way to studies that perceive CF as a 'systemic disease', linking the lung and the gut in a joined axis.

  5. Nasal Potential Difference in Cystic Fibrosis considering Severe CFTR Mutations

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    Ronny Tah Yen Ng

    2015-01-01

    Full Text Available The gold standard for diagnosing cystic fibrosis (CF is a sweat chloride value above 60 mEq/L. However, this historical and important tool has limitations; other techniques should be studied, including the nasal potential difference (NPD test. CFTR gene sequencing can identify CFTR mutations, but this method is time-consuming and too expensive to be used in all CF centers. The present study compared CF patients with two classes I-III CFTR mutations (10 patients (G1, CF patients with classes IV-VI CFTR mutations (five patients (G2, and 21 healthy subjects (G3. The CF patients and healthy subjects also underwent the NPD test. A statistical analysis was performed using the Mann-Whitney, Kruskal-Wallis, χ2, and Fisher’s exact tests, α=0.05. No differences were observed between the CF patients and healthy controls for the PDMax, Δamiloride, and Δchloride + free + amiloride markers from the NPD test. For the finger value, a difference between G2 and G3 was described. The Wilschanski index values were different between G1 and G3. In conclusion, our data showed that NPD is useful for CF diagnosis when classes I-III CFTR mutations are screened. However, if classes IV-VI are considered, the NPD test showed an overlap in values with healthy subjects.

  6. CFTR and Ca2+ signaling in cystic fibrosis

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    Fabrice eAntigny

    2011-10-01

    Full Text Available Among the diverse physiological functions exerted by calcium signaling in living cells, its role in the regulation of protein biogenesis and trafficking remains incompletely understood. In cystic fibrosis (CF disease the most common CFTR (Cystic Fibrosis Transmembrane conductance Regulator mutation, F508del-CFTR generates a misprocessed protein that is abnormally retained in the endoplasmic reticulum (ER compartment, rapidly degraded by the ubiquitine/proteasome pathway and hence absent at the plasma membrane of CF epithelial cells. Recent studies have demonstrated that intracellular calcium signals consequent to activation of apical G protein-coupled receptors (GPCRs by different agonists are increased in CF airway epithelia. Moreover, the regulation of various intracellular calcium storage compartments, such as ER is also abnormal in CF cells. Although the molecular mechanism to explain this increase remains puzzling in epithelial cells, the F508del-CFTR mutation is proposed to be the origin of abnormal Ca2+ influx linking the calcium signaling to CFTR pathobiology. This article reviews the relationships between CFTR and calcium signaling in the context of the genetic disease cystic fibrosis.

  7. Amniotic Mesenchymal Stem Cells: A New Source for Hepatocyte-Like Cells and Induction of CFTR Expression by Coculture with Cystic Fibrosis Airway Epithelial Cells

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    Valentina Paracchini

    2012-01-01

    Full Text Available Cystic fibrosis (CF is a monogenic disease caused by mutations in the CF transmembrane conductance regulator (CFTR gene, with lung and liver manifestations. Because of pitfalls of gene therapy, novel approaches for reconstitution of the airway epithelium and CFTR expression should be explored. In the present study, human amniotic mesenchymal stem cells (hAMSCs were isolated from term placentas and characterized for expression of phenotypic and pluripotency markers, and for differentiation potential towards mesoderm (osteogenic and adipogenic lineages. Moreover, hAMSCs were induced to differentiate into hepatocyte-like cells, as demonstrated by mixed function oxidase activity and expression of albumin, alpha1-antitrypsin, and CK19. We also investigated the CFTR expression in hAMSCs upon isolation and in coculture with CF airway epithelial cells. Freshly isolated hAMSCs displayed low levels of CFTR mRNA, which even decreased with culture passages. Following staining with the vital dye CM-DiI, hAMSCs were mixed with CFBE41o- respiratory epithelial cells and seeded onto permeable filters. Flow cytometry demonstrated that 33–50% of hAMSCs acquired a detectable CFTR expression on the apical membrane, a result confirmed by confocal microscopy. Our data show that amniotic MSCs have the potential to differentiate into epithelial cells of organs relevant in CF pathogenesis and may contribute to partial correction of the CF phenotype.

  8. Functional cure of SIVagm infection in rhesus macaques results in complete recovery of CD4+ T cells and is reverted by CD8+ cell depletion.

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    Ivona Pandrea

    2011-08-01

    Full Text Available Understanding the mechanism of infection control in elite controllers (EC may shed light on the correlates of control of disease progression in HIV infection. However, limitations have prevented a clear understanding of the mechanisms of elite controlled infection, as these studies can only be performed at randomly selected late time points in infection, after control is achieved, and the access to tissues is limited. We report that SIVagm infection is elite-controlled in rhesus macaques (RMs and therefore can be used as an animal model for EC HIV infection. A robust acute infection, with high levels of viral replication and dramatic mucosal CD4(+ T cell depletion, similar to pathogenic HIV-1/SIV infections of humans and RMs, was followed by complete and durable control of SIVagm replication, defined as: undetectable VLs in blood and tissues beginning 72 to 90 days postinoculation (pi and continuing at least 4 years; seroreversion; progressive recovery of mucosal CD4(+ T cells, with complete recovery by 4 years pi; normal levels of T cell immune activation, proliferation, and apoptosis; and no disease progression. This "functional cure" of SIVagm infection in RMs could be reverted after 4 years of control of infection by depleting CD8 cells, which resulted in transient rebounds of VLs, thus suggesting that control may be at least in part immune mediated. Viral control was independent of MHC, partial APOBEC restriction was not involved in SIVagm control in RMs and Trim5 genotypes did not impact viral replication. This new animal model of EC lentiviral infection, in which complete control can be predicted in all cases, permits research on the early events of infection in blood and tissues, before the defining characteristics of EC are evident and when host factors are actively driving the infection towards the EC status.

  9. Expression of TRPC3 in Chinese hamster ovary cells results in calcium-activated cation currents not related to store depletion.

    Science.gov (United States)

    Zitt, C; Obukhov, A G; Strübing, C; Zobel, A; Kalkbrenner, F; Lückhoff, A; Schultz, G

    1997-09-22

    TRPC3 (or Htrp3) is a human member of the trp family of Ca2+-permeable cation channels. Since expression of TRPC3 cDNA results in markedly enhanced Ca2+ influx in response to stimulation of membrane receptors linked to phospholipase C (Zhu, X., J. Meisheng, M. Peyton, G. Bouley, R. Hurst, E. Stefani, and L. Birnbaumer. 1996. Cell. 85:661-671), we tested whether TRPC3 might represent a Ca2+ entry pathway activated as a consequence of depletion of intracellular calcium stores. CHO cells expressing TRPC3 after intranuclear injection of cDNA coding for TRPC3 were identified by fluorescence from green fluorescent protein. Expression of TRPC3 produced cation currents with little selectivity for Ca2+ over Na+. These currents were constitutively active, not enhanced by depletion of calcium stores with inositol-1,4,5-trisphosphate or thapsigargin, and attenuated by strong intracellular Ca2+ buffering. Ionomycin led to profound increases of currents, but this effect was strictly dependent on the presence of extracellular Ca2+. Likewise, infusion of Ca2+ into cell through the patch pipette increased TRPC3 currents. Therefore, TRPC3 is stimulated by a Ca2+-dependent mechanism. Studies on TRPC3 in inside-out patches showed cation-selective channels with 60-pS conductance and short (ionomycin to cells increased channel activity in cell-attached patches. Increasing the Ca2+ concentration on the cytosolic side of inside-out patches (from 0 to 1 and 30 microM), however, failed to stimulate channel activity, even in the presence of calmodulin (0.2 microM). We conclude that TRPC3 codes for a Ca2+-permeable channel that supports Ca2+-induced Ca2+-entry but should not be considered store operated. PMID:9298988

  10. Diagnosis of cystic fibrosis in the kindred of an infant with CFTR-related metabolic syndrome: Importance of follow-up that includes monitoring sweat chloride concentrations over time

    OpenAIRE

    Williams, SN; Nussbaum, E.; Chin, TW; Do, PCM; Singh, KE; Randhawa, I

    2014-01-01

    Newly implemented newborn screening (NBS) programs in California have resulted in a large subset of patients in whom at least two cystic fibrosis transmembrane conductance regulator (CFTR) mutations are identified, but subsequent sweat chloride analysis reveals normal or indeterminate values. These patients are diagnosed with CFTR-Related Metabolic Syndrome (CRMS). However, the natural progression and management of these patients are not clearly understood and frequently after the age of 1-ye...

  11. A molecular mechanism for aberrantCFTR-dependent HCO3– transport in cystic fibrosis

    OpenAIRE

    Ko, Shigeru B. H.; Shcheynikov, Nikolay; Choi, Joo Young; Luo, Xiang; Ishibashi, Kenichi; Thomas, Philip J.; Kim, Joo Young; Kim, Kyung Hwan; Lee, Min Goo; Naruse, Satoru; Muallem, Shmuel

    2002-01-01

    Aberrant HCO3– transport is a hallmark of cystic fibrosis (CF) and is associated with aberrant Cl–-dependent HCO3– transport by the cystic fibrosis transmembrane conductance regulator (CFTR). We show here that HCO3– current by CFTR cannot account for CFTR-activated HCO3– transport and that CFTR does not activate AE1–AE4. In contrast, CFTR markedly activates Cl– and OH–/HCO3– transport by members of the SLC26 family DRA, SLC26A6 and pendrin. Most notably, the SLC26s are electrogenic transporte...

  12. Technology evaluation: AAV-CFTR vector, targeted genetics.

    Science.gov (United States)

    Tebbutt, S J

    1999-08-01

    Targeted Genetics is developing a gene therapy product, the AAV-CFTR vector system, for the treatment of cystic fibrosis (CF). This involves administration of an adeno-associated virus (AAV) vector containing CF transmembrane conductance regulator gene (CFTR) directly to the lungs of cystic fibrosis patients. The drug has Orphan Drug Status [325713]. Medeva acquired the worldwide commercial rights to the therapy in November 1998. Medeva expects to file a license application for the therapy, in the US and Europe, by 2002 [325713]. The therapy utilizing the normal CFTR gene entered phase II trials for sinusitis [197407] and phase II trials for CF in the first quarter of 1997. Lehman Brothers predicts filing in 2001/2002 [318119]. PMID:11713770

  13. Mechanosensitive activation of CFTR by increased cell volume and hydrostatic pressure but not shear stress.

    Science.gov (United States)

    Vitzthum, Constanze; Clauss, Wolfgang G; Fronius, Martin

    2015-11-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) is a Cl(-) channel that is essential for electrolyte and fluid homeostasis. Preliminary evidence indicates that CFTR is a mechanosensitive channel. In lung epithelia, CFTR is exposed to different mechanical forces such as shear stress (Ss) and membrane distention. The present study questioned whether Ss and/or stretch influence CFTR activity (wild type, ∆F508, G551D). Human CFTR (hCFTR) was heterologously expressed in Xenopus oocytes and the response to the mechanical stimulus and forskolin/IBMX (FI) was measured by two-electrode voltage-clamp experiments. Ss had no influence on hCFTR activity. Injection of an intracellular analogous solution to increase cell volume alone did not affect hCFTR activity. However, hCFTR activity was augmented by injection after pre-stimulation with FI. The response to injection was similar in channels carrying the common mutations ∆F508 and G551D compared to wild type hCFTR. Stretch-induced CFTR activation was further assessed in Ussing chamber measurements using Xenopus lung preparations. Under control conditions increased hydrostatic pressure (HP) decreased the measured ion current including activation of a Cl(-) secretion that was unmasked by the CFTR inhibitor GlyH-101. These data demonstrate activation of CFTR in vitro and in a native pulmonary epithelium in response to mechanical stress. Mechanosensitive regulation of CFTR is highly relevant for pulmonary physiology that relies on ion transport processes facilitated by pulmonary epithelial cells. PMID:26357939

  14. Partial correction of the CFTR-dependent ABPA mouse model with recombinant adeno-associated virus gene transfer of truncated CFTR gene.

    Science.gov (United States)

    Mueller, Christian; Torrez, Daniel; Braag, Sofia; Martino, Ashley; Clarke, Tracy; Campbell-Thompson, Martha; Flotte, Terence R

    2008-01-01

    Recently, we have developed a model of airway inflammation in a CFTR knockout mouse utilizing Aspergillus fumigatus crude protein extract (Af-cpe) to mimic allergic bronchopulmonary aspergillosis (ABPA) 1, an unusual IgE-mediated hypersensitivity syndrome seen in up to 15% of cystic fibrosis (CF) patients and rarely elsewhere. We hypothesized that replacement of CFTR via targeted gene delivery to airway epithelium would correct aberrant epithelial cytokine signaling and ameliorate the ABPA phenotype in CFTR-deficient (CFTR 489X - /-, FABP-hCFTR + / +) mice. CFTR knockout mice underwent intra-tracheal (IT) delivery of recombinant adeno-associated virus serotype 5 (rAAV5Delta-264CFTR) or rAAV5-GFP at 2.58 x 10(12) viral genomes/mouse. All mice were then sensitized with two serial injections (200 microg) of crude Af antigen via the intra-peritoneal (IP) route. Untreated mice were sensitized without virus exposure. Challenges were performed 2 weeks after final sensitization, using a 0.25% solution containing Aspergillus fumigatus crude protein extract delivered by inhalation on three consecutive days. The rAAV5Delta-264CFTR-treated mice had lower total serum IgE levels (172513 ng/ml +/- 1312) than rAAV5-GFP controls (26 892 ng/ml +/- 3715) (p = 0.037) and non-treated, sensitized controls (24 816 +/- 4219 ng/ml). Serum IgG1 levels also were lower in mice receiving the CFTR vector. Interestingly, splenocytes from rAAV5Delta-264CFTR-treated mice secreted less IL-13, INFg, TNFa, RANTES and GM-CSF after ConA stimulation. Gene therapy with rAAV5Delta-264CFTR attenuated the hyper-IgE response in this reproducible CF mouse model of ABPA, with systemic effects also evident in the cytokine response of stimulated splenocytes. PMID:18023072

  15. CFTR Mutations in Congenital Absence of Vas Deferens

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    Ramin Radpour

    2007-01-01

    Full Text Available A qualitative diagnosis of infertility requires attention to female and male physical abnormalities,endocrine anomalies and genetic conditions that interfere with reproduction. Many genes arelikely to be involved in the complex process of reproduction. Cystic fibrosis (CF incidence variesin different White people populations (a higher incidence of CF is observed in northern–westernEuropean populations than in southern European populations, and therefore the incidence ofcongenital bilateral absence of the vas deferens (CBAVD may also vary in different Whitepeople populations. As CF is mainly observed in White people, hardly any data are available ofCBAVD in non-White people, but frequent polymorphisms such as 5T are observed in mostpopulations. The spectrum and distribution of cystic fibrosis transmembrane conductanceregulator gene (CFTR mutations differs between CBAVD and CF patients, and even comparedwith control individuals. Combinations of particular alleles at several polymorphic loci yieldinsufficient functional CFTR. The combination of the 5T allele in one copy of the CFTR genewith a cystic fibrosis mutation in the other copy is the most common cause of CBAVD in Iran.Because of techniques such as intracytoplasmic sperm injection (ICSI, CBAVD patients are nowable to father children, however such couples have an increased risk of having a child with cysticfibrosis, and therefore genetic testing and counseling should be provided. Around 10% ofobstructive azoospermia is congenital and is due to mutations the CF gene. This paper reviews therelationship of mutations in the CFTR gene with CBAVD.

  16. Bioelectric characterization of epithelia from neonatal CFTR knockout ferrets

    NARCIS (Netherlands)

    J.T. Fisher (John); S.R. Tyler (Scott); Y. Zhang (Yulong); B.J. Lee (Ben); X. Liu (Xiaoming); X. Sun (Xinying); H. Sui (Hongshu); B. Liang (Bo); M. Luo (Ma); W. Xie (Weiliang); I. Yi (Iasson); W. Zhou (Weili); Y. Song (Yiqing); N. Keiser (Nicholas); K. Wang (Kai); H.R. de Jonge (Hugo); J.F. Engelhardt (John)

    2013-01-01

    textabstractCystic fibrosis (CF) is a life-shortening, recessive, multiorgan genetic disorder caused by the loss of CF transmembrane conductance regulator (CFTR) chloride channel function found in many types of epithelia. Animal models that recapitulate the human disease phenotype are critical to un

  17. Insulin-like growth factor 1 (IGF-1 enhances the protein expression of CFTR.

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    Ha Won Lee

    Full Text Available Low levels of insulin-like growth factor 1 (IGF-1 have been observed in the serum of cystic fibrosis (CF patients. However, the effects of low serum IGF-1 on the cystic fibrosis transmembrane conductance regulator (CFTR, whose defective function is the primary cause of cystic fibrosis, have not been studied. Here, we show in human cells that IGF-1 increases the steady-state levels of mature wildtype CFTR in a CFTR-associated ligand (CAL- and TC10-dependent manner; moreover, IGF-1 increases CFTR-mediated chloride transport. Using an acceptor photobleaching fluorescence resonance energy transfer (FRET assay, we have confirmed the binding of CAL and CFTR in the Golgi. We also show that CAL overexpression inhibits forskolin-induced increases in the cell-surface expression of CFTR. We found that IGF-1 activates TC10, and active TC10 alters the functional association between CAL and CFTR. Furthermore, IGF-1 and active TC10 can reverse the CAL-mediated reduction in the cell-surface expression of CFTR. IGF-1 does not increase the expression of ΔF508 CFTR, whose processing is arrested in the ER. This finding is consistent with our observation that IGF-1 alters the functional interaction of CAL and CFTR in the Golgi. However, when ΔF508 CFTR is rescued with low temperature or the corrector VRT-325 and proceeds to the Golgi, IGF-1 can increase the expression of the rescued ΔF508 CFTR. Our data support a model indicating that CAL-CFTR binding in the Golgi inhibits CFTR trafficking to the cell surface, leading CFTR to the degradation pathway instead. IGF-1-activated TC10 changes the interaction of CFTR and CAL, allowing CFTR to progress to the plasma membrane. These findings offer a potential strategy using a combinational treatment of IGF-1 and correctors to increase the post-Golgi expression of CFTR in cystic fibrosis patients bearing the ΔF508 mutation.

  18. Optimal correction of distinct CFTR folding mutants in rectal cystic fibrosis organoids.

    Science.gov (United States)

    Dekkers, Johanna F; Gogorza Gondra, Ricardo A; Kruisselbrink, Evelien; Vonk, Annelotte M; Janssens, Hettie M; de Winter-de Groot, Karin M; van der Ent, Cornelis K; Beekman, Jeffrey M

    2016-08-01

    Small-molecule therapies that restore defects in cystic fibrosis transmembrane conductance regulator (CFTR) gating (potentiators) or trafficking (correctors) are being developed for cystic fibrosis (CF) in a mutation-specific fashion. Options for pharmacological correction of CFTR-p.Phe508del (F508del) are being extensively studied but correction of other trafficking mutants that may also benefit from corrector treatment remains largely unknown.We studied correction of the folding mutants CFTR-p.Phe508del, -p.Ala455Glu (A455E) and -p.Asn1303Lys (N1303K) by VX-809 and 18 other correctors (C1-C18) using a functional CFTR assay in human intestinal CF organoids.Function of both CFTR-p.Phe508del and -p.Ala455Glu was enhanced by a variety of correctors but no residual or corrector-induced activity was associated with CFTR-p.Asn1303Lys. Importantly, VX-809-induced correction was most dominant for CFTR-p.Phe508del, while correction of CFTR-p.Ala455Glu was highest by a subgroup of compounds called bithiazoles (C4, C13, C14 and C17) and C5.These data support the development of mutation-specific correctors for optimal treatment of different CFTR trafficking mutants, and identify C5 and bithiazoles as the most promising compounds for correction of CFTR-p.Ala455Glu. PMID:27103391

  19. In vivo pharmacology and antidiarrheal efficacy of a thiazolidinone CFTR inhibitor in rodents.

    Science.gov (United States)

    Sonawane, N D; Muanprasat, Chatchai; Nagatani, Ray; Song, Yuanlin; Verkman, A S

    2005-01-01

    A small-molecule inhibitor of the cystic fibrosis transmembrane conductance regulator (CFTR), 3-[(3-trifluoromethyl)phenyl]-5-[(4-carboxyphenyl)methylene]-2-thioxo-4-thiazolidinone (CFTR(inh)-172), reduces enterotoxin-induced intestinal fluid secretion in rodents. Here, we study CFTR(inh)-172 pharmacology and antidiarrheal efficacy in rodents using (14)C-labeled CFTR(inh)-172, liquid chromatography/mass spectrometry, and a closed intestinal loop model of fluid secretion. CFTR(inh)-172 was cleared primarily by renal glomerular filtration without chemical modification. CFTR(inh)-172 accumulated in liver within 5 min after intravenous infusion in mice, and was concentrated fivefold in bile over blood. At 30-240 min, CFTR(inh)-172 was found mainly in liver, intestine, and kidney, with little detectable in the brain, heart, skeletal muscle, or lung. Pharmacokinetic analysis in rats following intravenous bolus infusion showed a distribution volume of 770 mL with redistribution and elimination half-times of 0.14 h and 10.3 h, respectively. CFTR(inh)-172 was stable in hepatic microsomes. Closed-loop studies in mice indicated that a single intraperitoneal injection of 20 microg CFTR(inh)-172 inhibited fluid accumulation at 6 h after cholera toxin by >90% in duodenum and jejunum, approximately 60% in ileum and accumulation of CFTR(inh)-172 account for its efficacy as an antidiarrheal. PMID:15761937

  20. How Phosphorylation and ATPase Activity Regulate Anion Flux though the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR).

    Science.gov (United States)

    Zwick, Matthias; Esposito, Cinzia; Hellstern, Manuel; Seelig, Anna

    2016-07-01

    The cystic fibrosis transmembrane conductance regulator (CFTR, ABCC7), mutations of which cause cystic fibrosis, belongs to the ATP-binding cassette (ABC) transporter family and works as a channel for small anions, such as chloride and bicarbonate. Anion channel activity is known to depend on phosphorylation by cAMP-dependent protein kinase A (PKA) and CFTR-ATPase activity. Whereas anion channel activity has been extensively investigated, phosphorylation and CFTR-ATPase activity are still poorly understood. Here, we show that the two processes can be measured in a label-free and non-invasive manner in real time in live cells, stably transfected with CFTR. This study reveals three key findings. (i) The major contribution (≥90%) to the total CFTR-related ATP hydrolysis rate is due to phosphorylation by PKA and the minor contribution (≤10%) to CFTR-ATPase activity. (ii) The mutant CFTR-E1371S that is still conductive, but defective in ATP hydrolysis, is not phosphorylated, suggesting that phosphorylation requires a functional nucleotide binding domain and occurs in the post-hydrolysis transition state. (iii) CFTR-ATPase activity is inversely related to CFTR anion flux. The present data are consistent with a model in which CFTR is in a closed conformation with two ATPs bound. The open conformation is induced by ATP hydrolysis and corresponds to the post-hydrolysis transition state that is stabilized by phosphorylation and binding of chloride channel potentiators. PMID:27226582

  1. Depletion of intense fields

    CERN Document Server

    Seipt, D; Marklund, M; Bulanov, S S

    2016-01-01

    The interaction of charged particles and photons with intense electromagnetic fields gives rise to multi-photon Compton and Breit-Wheeler processes. These are usually described in the framework of the external field approximation, where the electromagnetic field is assumed to have infinite energy. However, the multi-photon nature of these processes implies the absorption of a significant number of photons, which scales as the external field amplitude cubed. As a result, the interaction of a highly charged electron bunch with an intense laser pulse can lead to significant depletion of the laser pulse energy, thus rendering the external field approximation invalid. We provide relevant estimates for this depletion and find it to become important in the interaction between fields of amplitude $a_0 \\sim 10^3$ and electron bunches with charges of the order of nC.

  2. Depletion of regulatory T cells in a hapten-induced inflammation model results in prolonged and increased inflammation driven by T cells

    DEFF Research Database (Denmark)

    Christensen, A. D.; Skov, Søren; Kvist, P. H.;

    2015-01-01

    Regulatory T cells (Tregs ) are known to play an immunosuppressive role in the response of contact hypersensitivity (CHS), but neither the dynamics of Tregs during the CHS response nor the exaggerated inflammatory response after depletion of Tregs has been characterized in detail. In this study we...

  3. Depletion of mucin in mucin-producing human gastrointestinal carcinoma: Results from in vitro and in vivo studies with bromelain and N-acetylcysteine.

    Science.gov (United States)

    Amini, Afshin; Masoumi-Moghaddam, Samar; Ehteda, Anahid; Liauw, Winston; Morris, David L

    2015-10-20

    Aberrant expression of membrane-associated and secreted mucins, as evident in epithelial tumors, is known to facilitate tumor growth, progression and metastasis, and to provide protection against adverse growth conditions, chemotherapy and immune surveillance. Emerging evidence provides support for the oncogenic role of MUC1 in gastrointestinal carcinomas and relates its expression to an invasive phenotype. Similarly, mucinous differentiation of gastrointestinal tumors, in particular increased or de novo expression of MUC2 and/or MUC5AC, is widely believed to imply an adverse clinicopathological feature. Through formation of viscous gels, too, MUC2 and MUC5AC significantly contribute to the biology and pathogenesis of mucin-secreting gastrointestinal tumors. Here, we investigated the mucin-depleting effects of bromelain (BR) and N-acetylcysteine (NAC), in nine different regimens as single or combination therapy, in in vitro (MKN45, KATOIII and LS174T cell lines) and in vivo (female nude mice bearing intraperitoneal MKN45 and LS174T) settings. The inhibitory effects of the treatment on cancer cell growth and proliferation were also evaluated in vivo. Our results suggest that a combination of BR and NAC with dual effects on growth and mucin products of mucin-expressing tumor cells is a promising candidate towards the development of novel approaches to gastrointestinal malignancies with the involvement of mucin pathology. This capability supports the use of this combination formulation in locoregional approaches for reducing the adverse effects of the aberrantly secreted gel-forming mucins, as in pseudomyxoma peritonei and similar pathologies with ectopic production of mucin. PMID:26436698

  4. Lumacaftor-Ivacaftor in Patients with Cystic Fibrosis Homozygous for Phe508del CFTR

    DEFF Research Database (Denmark)

    Wainwright, Claire E; Elborn, J Stuart; Ramsey, Bonnie W;

    2015-01-01

    BACKGROUND: Cystic fibrosis is a life-limiting disease that is caused by defective or deficient cystic fibrosis transmembrane conductance regulator (CFTR) protein activity. Phe508del is the most common CFTR mutation. METHODS: We conducted two phase 3, randomized, double-blind, placebo......-controlled studies that were designed to assess the effects of lumacaftor (VX-809), a CFTR corrector, in combination with ivacaftor (VX-770), a CFTR potentiator, in patients 12 years of age or older who had cystic fibrosis and were homozygous for the Phe508del CFTR mutation. In both studies, patients were randomly...... homozygous for the Phe508del CFTR mutation. (Funded by Vertex Pharmaceuticals and others; TRAFFIC and TRANSPORT ClinicalTrials.gov numbers, NCT01807923 and NCT01807949.)....

  5. Restoration of NBD1 thermal stability is necessary and sufficient to correct ∆F508 CFTR folding and assembly.

    Science.gov (United States)

    He, Lihua; Aleksandrov, Andrei A; An, Jianli; Cui, Liying; Yang, Zhengrong; Brouillette, Christie G; Riordan, John R

    2015-01-16

    Cystic fibrosis transmembrane conductance regulator (CFTR) (ABCC7), unique among ABC exporters as an ion channel, regulates ion and fluid transport in epithelial tissues. Loss of function due to mutations in the cftr gene causes cystic fibrosis. The most common cystic-fibrosis-causing mutation, the deletion of F508 (ΔF508) from the first nucleotide binding domain (NBD1) of CFTR, results in misfolding of the protein and clearance by cellular quality control systems. The ΔF508 mutation has two major impacts on CFTR: reduced thermal stability of NBD1 and disruption of its interface with membrane-spanning domains (MSDs). It is unknown if these two defects are independent and need to be targeted separately. To address this question, we varied the extent of stabilization of NBD1 using different second-site mutations and NBD1 binding small molecules with or without NBD1/MSD interface mutation. Combinations of different NBD1 changes had additive corrective effects on ∆F508 maturation that correlated with their ability to increase NBD1 thermostability. These effects were much larger than those caused by interface modification alone and accounted for most of the correction achieved by modifying both the domain and the interface. Thus, NBD1 stabilization plays a dominant role in overcoming the ΔF508 defect. Furthermore, the dual target approach resulted in a locked-open ion channel that was constitutively active in the absence of the normally obligatory dependence on phosphorylation by protein kinase A. Thus, simultaneous targeting of both the domain and the interface, as well as being non-essential for correction of biogenesis, may disrupt normal regulation of channel function. PMID:25083918

  6. Restoration of NBD1 thermal stability is necessary and sufficient to correct ΔF508 CFTR folding and assembly

    Science.gov (United States)

    He, Lihua; Aleksandrov, Andrei A; An, Jianli; Cui, Liying; Yang, Zhengrong; Brouillette, Christie G.; Riordan, John R

    2015-01-01

    CFTR (ABCC7), unique among ABC exporters as an ion channel, regulates ion and fluid transport in epithelial tissues. Loss of function due to mutations in the cftr gene causes cystic fibrosis (CF). The most common CF-causing mutation, the deletion of F508 (ΔF508) from the first nucleotide binding domain (NBD1) of CFTR, results in misfolding of the protein and clearance by cellular quality control systems. The ΔF508 mutation has two major impacts on CFTR: reduced thermal stability of NBD1 and disruption of its interface with membrane-spanning domains (MSDs). It is unknown if these two defects are independent and need to be targeted separately. To address this question we varied the extent of stabilization of NBD1 using different second site mutations and NBD1 binding small molecules with or without NBD1/MSD interface mutation. Combinations of different NBD1 changes had additive corrective effects on ΔF508 maturation that correlated with their ability to increase NBD1 thermostability. These effects were much larger than those caused by interface modification alone and accounted for most of the correction achieved by modifying both the domain and the interface. Thus, NBD1 stabilization plays a dominant role in overcoming the ΔF508 defect. Furthermore, the dual target approach resulted in a locked-open ion channel that was constitutively active in the absence of the normally obligatory dependence on phosphorylation by protein kinase A. Thus, simultaneous targeting of both the domain and the interface, as well as being non-essential for correction of biogenesis, may disrupt normal regulation of channel function. PMID:25083918

  7. Impact of heterozygote CFTR Mutations in COPD patients with Chronic Bronchitis

    OpenAIRE

    Raju, S. Vamsee; Tate, Jody H; Peacock, Sandra KG; Fang, Ping; Oster, Robert A.; Dransfield, Mark T.; Steven M Rowe

    2014-01-01

    Background Cigarette smoking causes Chronic Obstructive Pulmonary Disease (COPD), the 3rd leading cause of death in the U.S. CFTR ion transport dysfunction has been implicated in COPD pathogenesis, and is associated with chronic bronchitis. However, susceptibility to smoke induced lung injury is variable and the underlying genetic contributors remain unclear. We hypothesized that presence of CFTR mutation heterozygosity may alter susceptibility to cigarette smoke induced CFTR dysfunction. Con...

  8. Stable ATP binding mediated by a partial NBD dimer of the CFTR chloride channel

    OpenAIRE

    Tsai, Ming-Feng; Li, Min; Hwang, Tzyh-Chang

    2010-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR), a member of the adenosine triphosphate (ATP) binding cassette (ABC) superfamily, is an ATP-gated chloride channel. Like other ABC proteins, CFTR encompasses two nucleotide binding domains (NBDs), NBD1 and NBD2, each accommodating an ATP binding site. It is generally accepted that CFTR’s opening–closing cycles, each completed within 1 s, are driven by rapid ATP binding and hydrolysis events in NBD2. Here, by recording CFTR currents in...

  9. Cholic acid induces a Cftr dependent biliary secretion and liver growth response in mice.

    Directory of Open Access Journals (Sweden)

    Frank A J A Bodewes

    Full Text Available The cause of Cystic fibrosis liver disease (CFLD, is unknown. It is well recognized that hepatic exposure to hydrophobic bile salts is associated with the development of liver disease. For this reason, we hypothesize that, CFTR dependent variations, in the hepatic handling of hydrophobic bile salts, are related to the development CFLD. To test our hypothesis we studied, in Cftr-/- and control mice, bile production, bile composition and liver pathology, in normal feeding condition and during cholate exposure, either acute (intravenous or chronic (three weeks via the diet. In Cftr-/- and control mice the basal bile production was comparable. Intravenous taurocholate increased bile production to the same extent in Cftr-/- and control mice. However, chronic cholate exposure increased the bile flow significantly less in Cftr-/- mice than in controls, together with significantly higher biliary bile salt concentration in Cftr-/- mice. Prolonged cholate exposure, however, did not induce CFLD like pathology in Cftr-/- mice. Chronic cholate exposure did induce a significant increase in liver mass in controls that was absent in Cftr-/- mice. Chronic cholate administration induces a cystic fibrosis-specific hepatobiliary phenotype, including changes in bile composition. These changes could not be associated with CFLD like pathological changes in CF mouse livers. However, chronic cholate administration induces liver growth in controls that is absent in Cftr-/- mice. Our findings point to an impaired adaptive homeotrophic liver response to prolonged hydrophobic bile salt exposure in CF conditions.

  10. β2-Adrenergic receptor agonists activate CFTR in intestinal organoids and subjects with cystic fibrosis.

    Science.gov (United States)

    Vijftigschild, Lodewijk A W; Berkers, Gitte; Dekkers, Johanna F; Zomer-van Ommen, Domenique D; Matthes, Elizabeth; Kruisselbrink, Evelien; Vonk, Annelotte; Hensen, Chantal E; Heida-Michel, Sabine; Geerdink, Margot; Janssens, Hettie M; van de Graaf, Eduard A; Bronsveld, Inez; de Winter-de Groot, Karin M; Majoor, Christof J; Heijerman, Harry G M; de Jonge, Hugo R; Hanrahan, John W; van der Ent, Cornelis K; Beekman, Jeffrey M

    2016-09-01

    We hypothesized that people with cystic fibrosis (CF) who express CFTR (cystic fibrosis transmembrane conductance regulator) gene mutations associated with residual function may benefit from G-protein coupled receptor (GPCR)-targeting drugs that can activate and enhance CFTR function.We used intestinal organoids to screen a GPCR-modulating compound library and identified β2-adrenergic receptor agonists as the most potent inducers of CFTR function.β2-Agonist-induced organoid swelling correlated with the CFTR genotype, and could be induced in homozygous CFTR-F508del organoids and highly differentiated primary CF airway epithelial cells after rescue of CFTR trafficking by small molecules. The in vivo response to treatment with an oral or inhaled β2-agonist (salbutamol) in CF patients with residual CFTR function was evaluated in a pilot study. 10 subjects with a R117H or A455E mutation were included and showed changes in the nasal potential difference measurement after treatment with oral salbutamol, including a significant improvement of the baseline potential difference of the nasal mucosa (+6.35 mV, pCFTR activation when administered ex vivo to organoids.This proof-of-concept study suggests that organoids can be used to identify drugs that activate CFTR function in vivo and to select route of administration. PMID:27471203

  11. SNaPshot Assay for the Detection of the Most Common CFTR Mutations in Infertile Men

    OpenAIRE

    Predrag Noveski; Svetlana Madjunkova; Marija Mircevska; Toso Plaseski; Vanja Filipovski; Dijana Plaseska-Karanfilska

    2014-01-01

    Congenital bilateral absence of vas deferens (CBAVD) is the most common CFTR-related disorder (CFTR-RD) that explains about 1-2% of the male infertility cases. Controversial data have been published regarding the involvement of CFTR mutations in infertile men with non-obstructive azoospermia and oligozoospermia. Here, we describe single base extension (SNaPshot) assay for detection of 11 common CFTR mutations: F508del, G542X, N1303K, 621+1G->T, G551D, R553X, R1162X, W1282X, R117H, 2184insA an...

  12. DEPLETED URANIUM TECHNICAL WORK

    Science.gov (United States)

    The Depleted Uranium Technical Work is designed to convey available information and knowledge about depleted uranium to EPA Remedial Project Managers, On-Scene Coordinators, contractors, and other Agency managers involved with the remediation of sites contaminated with this mater...

  13. Novel residues lining the CFTR chloride channel pore identified by functional modification of introduced cysteines.

    Science.gov (United States)

    Fatehi, Mohammad; Linsdell, Paul

    2009-04-01

    Substituted cysteine accessibility mutagenesis (SCAM) has been used widely to identify pore-lining amino acid side chains in ion channel proteins. However, functional effects on permeation and gating can be difficult to separate, leading to uncertainty concerning the location of reactive cysteine side chains. We have combined SCAM with investigation of the charge-dependent effects of methanethiosulfonate (MTS) reagents on the functional permeation properties of cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channels. We find that cysteines substituted for seven out of 21 continuous amino acids in the eleventh and twelfth transmembrane (TM) regions can be modified by external application of positively charged [2-(trimethylammonium)ethyl] MTS bromide (MTSET) and negatively charged sodium [2-sulfonatoethyl] MTS (MTSES). Modification of these cysteines leads to changes in the open channel current-voltage relationship at both the macroscopic and single-channel current levels that reflect specific, charge-dependent effects on the rate of Cl(-) permeation through the channel from the external solution. This approach therefore identifies amino acid side chains that lie within the permeation pathway. Cysteine mutagenesis of pore-lining residues also affects intrapore anion binding and anion selectivity, giving more information regarding the roles of these residues. Our results demonstrate a straightforward method of screening for pore-lining amino acids in ion channels. We suggest that TM11 contributes to the CFTR pore and that the extracellular loop between TMs 11 and 12 lies close to the outer mouth of the pore. PMID:19381710

  14. Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations in allergic bronchopulmonary aspergillosis

    Energy Technology Data Exchange (ETDEWEB)

    Miller, P.W.; Hamosh, A.; Macek, M. Jr. [John Hopkins Univ. School of Medicine, Baltimore, MD (United States)] [and others

    1996-07-01

    The etiology of allergic bronchopulmonary aspergillosis (ABPA) is not well understood. A clinical phenotype resembling the pulmonary disease seen in cystic fibrosis (CF) patients can occur in some individuals with ABPA. Reports of familial occurrence of ABPA and increased incidence in CF patients suggest a possible genetic basis for the disease. To test this possibility, the entire coding region of the cystic fibrosis transmembrane regulator (CFTR) gene was analyzed in 11 individuals who met strict criteria for the diagnosis of ABPA and had normal sweat electrolytes ({le}40 mmol/liter). One patient carried two CF mutations ({Delta}F508/R347H), and five were found to carry one CF mutation (four {Delta}F508; one R117H). The frequency of the {Delta}F508 mutation in patients with ABPA was significantly higher than in 53 Caucasian patients with chronic bronchitis (P < .0003) and the general population (P < .003). These results suggest that CFTR plays an etiologic role in a subset of ABPA patients. 54 refs., 2 tabs.

  15. Contribution of CFTR to Alveolar Fluid Clearance by Lipoxin A4 via PI3K/Akt Pathway in LPS-Induced Acute Lung Injury

    Directory of Open Access Journals (Sweden)

    Yi Yang

    2013-01-01

    Full Text Available The lipoxins are the first proresolution mediators to be recognized and described as the endogenous “braking signals” for inflammation. We evaluated the anti-inflammatory and proresolution bioactions of lipoxin A4 in our lipopolysaccharide (LPS-induced lung injury model. We demonstrated that lipoxin A4 significantly improved histology of rat lungs and inhibited IL-6 and TNF-α in LPS-induced lung injury. In addition, lipoxin A4 increased alveolar fluid clearance (AFC and the effect of lipoxin A4 on AFC was abolished by CFTRinh-172 (a specific inhibitor of CFTR. Moreover, lipoxin A4 could increase cystic fibrosis transmembrane conductance regulator (CFTR protein expression in vitro and in vivo. In rat primary alveolar type II (ATII cells, LPS decreased CFTR protein expression via activation of PI3K/Akt, and lipoxin A4 suppressed LPS-stimulated phosphorylation of Akt. These results showed that lipoxin A4 enhanced CFTR protein expression and increased AFC via PI3K/Akt pathway. Thus, lipoxin A4 may provide a potential therapeutic approach for acute lung injury.

  16. Lack of association between UGT1A7, UGT1A9, ARP, SPINK1 and CFTR gene polymorphisms and pancreatic cancer in Italian patients

    Institute of Scientific and Technical Information of China (English)

    Ada Piepoli; Annamaria Gentile; Maria Rosa Valvano; Daniela Barana; Cristina Oliani; Rosa Cotugno; Michele Quitadamo; Angelo Andriulli; Francesco Perri

    2006-01-01

    AIM: To investigate simultaneously UGT1A7, UGT1A9,ARP, SPINK and CFTR genes to verify whether genetic polymorphisms predispose to the development of pancreatic cancer (PC).METHODS: Genomic DNA of 61 pancreatic cancer patients and 105 healthy controls (HC) were analyzed.UGT1,47 genotyping was determined by PCR-RFLP analysis. Specific PCR and sequencing were used to analyze genetic variants of UGT1A9, ARP, SPINK1 and CFTR genes.RESULTS: Four different alleles (*1: WT;*2: N129Kand R131K;*3: N129K, R131K, and W208R;and *4:W208R) in UGT1A7 and three different alleles (*1: WT;*4: Y242X;and *5: D256N) in UGT1A9 were detected.All UGT1A polymorphisms were observed at similar frequency in PC patients and HC. Seven different alleles in ARP were found in PC patients and HC at similar frequency. The SPINK1 mutations N34S and P55Soccurred in five PC patients with a prevalence (4.1%) not significantly different from that observed (2.0%) in HC.The only CFTR ΔF508 mutation was recognized in three PC patients with a prevalence (4.9%) similar to HC.CONCLUSION: UGT1A7, UGT1A9, ARP, SPINK1 and CFTR gene polymorphisms are not associated with PC in Italian patients.

  17. Progesterone Downregulates Oestrogen-Induced Expression of CFTR and SLC26A6 Proteins and mRNA in Rats’ Uteri

    Directory of Open Access Journals (Sweden)

    K. Gholami

    2012-01-01

    Full Text Available Under progesterone (P dominance, fluid loss assists uterine closure which is associated with pH reduction. We hypothesize that P inhibits uterine fluid secretion and HCO3- transport. Aim. to investigate the expression of Cystic Fibrosis Transmembrane Regulator (CFTR and Cl−/HCO3- exchanger (SLC26A6 under P effect. Method. Uteri from ovariectomized steroid replaced and intact rats at different stages of oestrous cycle were analyzed for changes in protein and mRNA expressions. Results. P inhibits CFTR and SLC26A6 proteins and mRNA expression while oestrogen (E causes vice versa. E treatment followed by P causes a reduction in these transporters’ mRNA and protein. Similar changes occur throughout the oestrous cycle; that is, CFTR mRNA expression was high at proestrus while SLC26A6 mRNA and protein expressions were increased at proestrus and estrus. At diestrus, however, the expression of these transporters’ protein and mRNA was reduced. Conclusion. Inhibition of CFTR and SLC26A6 expressions may explain the reduced fluid volume and pH under P-mediated effect.

  18. Depleted uranium management alternatives

    International Nuclear Information System (INIS)

    This report evaluates two management alternatives for Department of Energy depleted uranium: continued storage as uranium hexafluoride, and conversion to uranium metal and fabrication to shielding for spent nuclear fuel containers. The results will be used to compare the costs with other alternatives, such as disposal. Cost estimates for the continued storage alternative are based on a life-cycle of 27 years through the year 2020. Cost estimates for the recycle alternative are based on existing conversion process costs and Capital costs for fabricating the containers. Additionally, the recycle alternative accounts for costs associated with intermediate product resale and secondary waste disposal for materials generated during the conversion process

  19. Spatial positioning of CFTR's pore-lining residues affirms an asymmetrical contribution of transmembrane segments to the anion permeation pathway.

    Science.gov (United States)

    Gao, Xiaolong; Hwang, Tzyh-Chang

    2016-05-01

    The structural composition of CFTR's anion permeation pathway has been proposed to consist of a short narrow region, flanked by two wide inner and outer vestibules, based on systematic cysteine scanning studies using thiol-reactive probes of various sizes. Although these studies identified several of the transmembrane segments (TMs) as pore lining, the exact spatial relationship between pore-lining elements remains under debate. Here, we introduce cysteine pairs in several key pore-lining positions in TM1, 6, and 12 and use Cd(2+) as a probe to gauge the spatial relationship of these residues within the pore. We find that inhibition of single cysteine CFTR mutants, such as 102C in TM1 or 341C in TM6, by intracellular Cd(2+) is readily reversible upon removal of the metal ion. However, the inhibitory effect of Cd(2+) on the double mutant 102C/341C requires the chelating agent dithiothreitol (DTT) for rapid reversal, indicating that 102C and 341C are close enough to the internal edge of the narrow region to coordinate one Cd(2+) ion between them. We observe similar effects of extracellular Cd(2+) on TM1/TM6 cysteine pairs 106C/337C, 107C/337C, and 107C/338C, corroborating the idea that these paired residues are physically close to each other at the external edge of the narrow region. Although these data paint a picture of relatively symmetrical contributions to CFTR's pore by TM1 and TM6, introducing cysteine pairs between TM6 and TM12 (348C/1141C, 348C/1144C, and 348C/1145C) or between TM1 and TM12 (95C/1141C) yields results that contest the long-held principle of twofold pseudo-symmetry in the assembly of ABC transporters' TMs. Collectively, these findings not only advance our current understanding of the architecture of CFTR's pore, but could serve as a guide for refining computational models of CFTR by imposing physical constraints among pore-lining residues. PMID:27114613

  20. Integrated biophysical studies implicate partial unfolding of NBD1 of CFTR in the molecular pathogenesis of F508del cystic fibrosis.

    Science.gov (United States)

    Wang, Chi; Protasevich, Irina; Yang, Zhengrong; Seehausen, Derek; Skalak, Timothy; Zhao, Xun; Atwell, Shane; Spencer Emtage, J; Wetmore, Diana R; Brouillette, Christie G; Hunt, John F

    2010-10-01

    The lethal genetic disease cystic fibrosis is caused predominantly by in-frame deletion of phenylalanine 508 in the cystic fibrosis transmembrane conductance regulator (CFTR). F508 is located in the first nucleotide-binding domain (NBD1) of CFTR, which functions as an ATP-gated chloride channel on the cell surface. The F508del mutation blocks CFTR export to the surface due to aberrant retention in the endoplasmic reticulum. While it was assumed that F508del interferes with NBD1 folding, biophysical studies of purified NBD1 have given conflicting results concerning the mutation's influence on domain folding and stability. We have conducted isothermal (this paper) and thermal (accompanying paper) denaturation studies of human NBD1 using a variety of biophysical techniques, including simultaneous circular dichroism, intrinsic fluorescence, and static light-scattering measurements. These studies show that, in the absence of ATP, NBD1 unfolds via two sequential conformational transitions. The first, which is strongly influenced by F508del, involves partial unfolding and leads to aggregation accompanied by an increase in tryptophan fluorescence. The second, which is not significantly influenced by F508del, involves full unfolding of NBD1. Mg-ATP binding delays the first transition, thereby offsetting the effect of F508del on domain stability. Evidence suggests that the initial partial unfolding transition is partially responsible for the poor in vitro solubility of human NBD1. Second-site mutations that increase the solubility of isolated F508del-NBD1 in vitro and suppress the trafficking defect of intact F508del-CFTR in vivo also stabilize the protein against this transition, supporting the hypothesize that it is responsible for the pathological trafficking of F508del-CFTR. PMID:20687163

  1. Integrated biophysical studies implicate partial unfolding of NBD1 of CFTR in the molecular pathogenesis of F508del cystic fibrosis

    Science.gov (United States)

    Wang, Chi; Protasevich, Irina; Yang, Zhengrong; Seehausen, Derek; Skalak, Timothy; Zhao, Xun; Atwell, Shane; Spencer Emtage, J; Wetmore, Diana R; Brouillette, Christie G; Hunt, John F

    2010-01-01

    The lethal genetic disease cystic fibrosis is caused predominantly by in-frame deletion of phenylalanine 508 in the cystic fibrosis transmembrane conductance regulator (CFTR). F508 is located in the first nucleotide-binding domain (NBD1) of CFTR, which functions as an ATP-gated chloride channel on the cell surface. The F508del mutation blocks CFTR export to the surface due to aberrant retention in the endoplasmic reticulum. While it was assumed that F508del interferes with NBD1 folding, biophysical studies of purified NBD1 have given conflicting results concerning the mutation's influence on domain folding and stability. We have conducted isothermal (this paper) and thermal (accompanying paper) denaturation studies of human NBD1 using a variety of biophysical techniques, including simultaneous circular dichroism, intrinsic fluorescence, and static light-scattering measurements. These studies show that, in the absence of ATP, NBD1 unfolds via two sequential conformational transitions. The first, which is strongly influenced by F508del, involves partial unfolding and leads to aggregation accompanied by an increase in tryptophan fluorescence. The second, which is not significantly influenced by F508del, involves full unfolding of NBD1. Mg-ATP binding delays the first transition, thereby offsetting the effect of F508del on domain stability. Evidence suggests that the initial partial unfolding transition is partially responsible for the poor in vitro solubility of human NBD1. Second-site mutations that increase the solubility of isolated F508del-NBD1 in vitro and suppress the trafficking defect of intact F508del-CFTR in vivo also stabilize the protein against this transition, supporting the hypothesize that it is responsible for the pathological trafficking of F508del-CFTR. PMID:20687163

  2. Mechanism-based corrector combination restores Delta F508-CFTR folding and function

    NARCIS (Netherlands)

    Okiyoneda, Tsukasa; Veit, Guido; Dekkers, Johanna F.; Bagdany, Miklos; Soya, Naoto; Xu, Haijin; Roldan, Ariel; Verkman, Alan S.; Kurth, Mark; Simon, Agnes; Hegedus, Tamas; Beekman, Jeffrey M.; Lukacs, Gergely L.

    2013-01-01

    The most common cystic fibrosis mutation, Delta F508 in nucleotide binding domain 1 (NBD1), impairs cystic fibrosis transmembrane conductance regulator (CFTR)-coupled domain folding, plasma membrane expression, function and stability. VX-809, a promising investigational corrector of Delta F508-CFTR

  3. Stimulation of Airway and Intestinal Mucosal Secretion by Natural Coumarin CFTR Activators

    OpenAIRE

    Hong eYang; Lina eXu; Yujie eSui; Xin eLiu; Chengyan eHe; Rouyu eFang; Jia eLiu; Feng eHao; Tong-Hui eMa

    2011-01-01

    Mutations of cystic fibrosis transmembrane conductance regulator (CFTR) cause lethal hereditary disease cystic fibrosis (CF) that involves extensive destruction and dysfunction of serous epithelium. Possible pharmacological therapy includes correction of defective intracellular processing and abnormal channel gating. In a previous study, we identified five natural coumarin potentiators of Δ508-CFTR including osthole, imperatorin, isopsoralen, praeruptorin A and scoparone. The present study wa...

  4. Depleted Uranium Management

    International Nuclear Information System (INIS)

    The paper considers radiological and toxic impact of the depleted uranium on the human health. Radiological influence of depleted uranium is less for 60 % than natural uranium due to the decreasing of short-lived isotopes uranium-234 and uranium-235 after enrichment. The formation of radioactive aerosols and their impact on the human are mentioned. Use of the depleted uranium weapons has also a chemical effect on intake due to possible carcinogenic influence on kidney. Uranium-236 in the substance of the depleted uranium is determined. The fact of beta-radiation formation in the uranium-238 decay is regarded. This effect practically is the same for both depleted and natural uranium. Importance of toxicity of depleted uranium, as the heavier chemical substance, has a considerable contribution to the population health. The paper analyzes risks regarding the use of the depleted uranium weapons. There is international opposition against using weapons with depleted uranium. Resolution on effects of the use of armaments and ammunitions containing depleted uranium was five times supported by the United Nations (USA, United Kingdom, France and Israel did not support). The decision for banning of depleted uranium weapons was supported by the European Parliament

  5. Evaluation of potential regulatory elements identified as DNase I hypersensitive sites in the CFTR gene

    DEFF Research Database (Denmark)

    Phylactides, M.; Rowntree, R.; Nuthall, H.;

    2002-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) gene shows a complex pattern of expression, with temporal and spatial regulation that is not accounted for by elements in the promoter. One approach to identifying the regulatory elements for CFTR is the mapping of DNase I...... hypersensitive sites (DHS) within the locus. We previously identified at least 12 clusters of DHS across the CFTR gene and here further evaluate DHS in introns 2,3,10,16,17a, 18, 20 and 21 to assess their functional importance in regulation of CFTR gene expression. Transient transfections of enhancer....../reporter constructs containing the DHS regions showed that those in introns 20 and 21 augmented the activity of the CFTR promoter. Structural analysis of the DNA sequence at the DHS suggested that only the one intron 21 might be caused by inherent DNA structures. Cell specificity of the DHS suggested a role for the...

  6. Manipulating proteostasis to repair the F508del-CFTR defect in cystic fibrosis.

    Science.gov (United States)

    Esposito, Speranza; Tosco, Antonella; Villella, Valeria R; Raia, Valeria; Kroemer, Guido; Maiuri, Luigi

    2016-12-01

    Cystic fibrosis (CF) is a lethal monogenic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene that entails the (diagnostic) increase in sweat electrolyte concentrations, progressive lung disease with chronic inflammation and recurrent bacterial infections, pancreatic insufficiency, and male infertility. Therapies aimed at restoring the CFTR defect have emerged. Thus, a small molecule which facilitates chloride channel opening, the potentiator Ivacaftor, has been approved for the treatment of CF patients bearing a particular class of rare CFTR mutations. However, small molecules that directly target the most common misfolded CFTR mutant, F508del, and improve its intracellular trafficking in vitro, have been less effective than expected when tested in CF patients, even in combination with Ivacaftor. Thus, new strategies are required to circumvent the F508del-CFTR defect. Airway and intestinal epithelial cells from CF patients bearing the F508del-CFTR mutation exhibit an impressive derangement of cellular proteostasis, with oxidative stress, overactivation of the tissue transglutaminase (TG2), and disabled autophagy. Proteostasis regulators such as cysteamine can rescue and stabilize a functional F508del-CFTR protein through suppressing TG2 activation and restoring autophagy in vivo in F508del-CFTR homozygous mice, in vitro in CF patient-derived cell lines, ex vivo in freshly collected primary patient's nasal cells, as well as in a pilot clinical trial involving homozygous F508del-CFTR patients. Here, we discuss how the therapeutic normalization of defective proteostasis can be harnessed for the treatment of CF patients with the F508del-CFTR mutation. PMID:26976279

  7. Thermal unfolding studies show the disease causing F508del mutation in CFTR thermodynamically destabilizes nucleotide-binding domain 1

    OpenAIRE

    Protasevich, Irina; Yang, Zhengrong; Wang, Chi; Atwell, Shane; Zhao, Xun; Emtage, Spencer; Wetmore, Diana; Hunt, John F.; Brouillette, Christie G

    2010-01-01

    Misfolding and degradation of CFTR is the cause of disease in patients with the most prevalent CFTR mutation, an in-frame deletion of phenylalanine (F508del), located in the first nucleotide-binding domain of human CFTR (hNBD1). Studies of (F508del)CFTR cellular folding suggest that both intra- and inter-domain folding is impaired. (F508del)CFTR is a temperature-sensitive mutant, that is, lowering growth temperature, improves both export, and plasma membrane residence times. Yet, paradoxicall...

  8. Clodronate treatment significantly depletes macrophages in chickens

    OpenAIRE

    Kameka, Amber M.; Haddadi, Siamak; Jamaldeen, Fathima Jesreen; Moinul, Prima; He, Xiao T.; Nawazdeen, Fathima Hafsa P.; Bonfield, Stephan; Sharif, Shayan; van Rooijen, Nico; Abdul-Careem, Mohamed Faizal

    2014-01-01

    Macrophages function as phagocytes and antigen-presenting cells in the body. As has been demonstrated in mammals, administration of clodronate [dichloromethylene bisphosphonate (Cl2MBP)] encapsulated liposomes results in depletion of macrophages. Although this compound has been used in chickens, its effectiveness in depleting macrophages has yet to be fully determined. Here, we show that a single administration of clodronate liposomes to chickens results in a significant depletion of macropha...

  9. Nonlinear lower hybrid wave depletion

    International Nuclear Information System (INIS)

    Two numerical ray tracing codes with focusing are used to compute lower hybrid daughter wave amplification by quasi-mode parametric decay. The first code, LHPUMP provides a numerical pump model on a grid. This model is used by a second code, LHFQM which computes daughter wave amplification inside the pump extent and follows the rays until their energy is absorbed by the plasma. An analytic model is then used to estimate pump depletion based on the numerical results. Results for PLT indicate strong pump depletion at the plasma edge at high density operation for the 800 Mhz wave frequency, but weak depletion for the 2.45 Ghz experiment. This is proposed to be the mechanism responsible for the high density limit for current drive as well as for the difficulty to heat ions

  10. A High-affinity Activator of G551D-CFTR Chloride Channel Identified By High Throughput Screening

    Institute of Scientific and Technical Information of China (English)

    ZHAO Lu; HE Cheng-yan; LIU Yan-li; ZHOU Hong-lan; ZHOU Jin-song; SHANG De-jing; YANG Hong

    2004-01-01

    A stably transfected CHO cell line coexpressing G551D-CFTR and iodide-sensitive yellow fluorescent protein mutant EYFP-H148Q-I152L was successfully established and used as assay model to identify small-molecule activators of G551D-CFTR chloride channel from 100000 diverse combinatorial compounds by high throughput screening on a customized Beckman robotic system. A bicyclooctane compound was identified to activate G551D-CFTR chloride channel with high-affinity(Kd=1.8 μmol/L). The activity of the bicyclooctane compound is G551D-CFTR-specific, reversible and non-toxic. The G551D-CFTR activator may be useful as a tool to study the mutant G551D-CFTR chloride channel structure and transport properties and as a candidate drug to cure cystic fibrosis caused by G551D-CFTR mutation.

  11. Preliminary results on low power sigmoid neuron transistor response in 28 nm high-k metal gate Fully Depleted SOI technology

    Science.gov (United States)

    Galy, Ph.; Dehan, P.; Jimenez, J.; Heitz, B.

    2013-11-01

    The purpose of this paper is to describe a preliminary approach to achieve a sigmoid neuron transistor response using the 28 nm high-k metal gate Fully Depleted SOI (FDSOI) technology. It is well known that a neural network is an ambitious way to handle signal and/or data flow. Of interest also is the 'learning phase' of the proposed structure. However, the major difficulty of such structures, where the elementary device is a "Neuron Design (ND)" is in their integration. The elementary ND is based upon a circuit with at least ten interconnected CMOS transistors in order to obtain a sigmoid response activation function (in this example) with multiple inputs typically as per the McCulloch and Pitts model. Given that a large number of NDs are required to build an Artificial Neural Network (ANN), the power consumption of such a structure is a key topic that is also addressed. Another open question concerns the dispersion response due to process variability. This study reports on a new single undoped Formal Neuron Transistor (NT) solution.

  12. Depleted uranium: Metabolic disruptor?

    International Nuclear Information System (INIS)

    The presence of uranium in the environment can lead to long-term contamination of the food chain and of water intended for human consumption and thus raises many questions about the scientific and societal consequences of this exposure on population health. Although the biological effects of chronic low-level exposure are poorly understood, results of various recent studies show that contamination by depleted uranium (DU) induces subtle but significant biological effects at the molecular level in organs including the brain, liver, kidneys and testicles. For the first time, it has been demonstrated that DU induces effects on several metabolic pathways, including those metabolizing vitamin D, cholesterol, steroid hormones, acetylcholine and xenobiotics. This evidence strongly suggests that DU might well interfere with many metabolic pathways. It might thus contribute, together with other man-made substances in the environment, to increased health risks in some regions. (authors)

  13. Riddle of depleted uranium

    International Nuclear Information System (INIS)

    Depleted Uranium (DU) is the waste product of uranium enrichment from the manufacturing of fuel rods for nuclear reactors in nuclear power plants and nuclear power ships. DU may also results from the reprocessing of spent nuclear reactor fuel. Potentially DU has both chemical and radiological toxicity with two important targets organs being the kidney and the lungs. DU is made into a metal and, due to its availability, low price, high specific weight, density and melting point as well as its pyrophoricity; it has a wide range of civilian and military applications. Due to the use of DU over the recent years, there appeared in some press on health hazards that are alleged to be due to DU. In these paper properties, applications, potential environmental and health effects of DU are briefly reviewed

  14. Thermodynamic study of the native and phosphorylated regulatory domain of the CFTR

    Energy Technology Data Exchange (ETDEWEB)

    Marasini, Carlotta, E-mail: marasini@ge.ibf.cnr.it [Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via De Marini 6, 16149 Genova (Italy); Galeno, Lauretta; Moran, Oscar [Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via De Marini 6, 16149 Genova (Italy)

    2012-07-06

    Highlights: Black-Right-Pointing-Pointer CFTR mutations produce cystic fibrosis. Black-Right-Pointing-Pointer Chloride transport depends on the regulatory domain phosphorylation. Black-Right-Pointing-Pointer Regulatory domain is intrinsically disordered. Black-Right-Pointing-Pointer Secondary structure and protein stability change upon phosphorylation. -- Abstract: The regulatory domain (RD) of the cystic fibrosis transmembrane conductance regulator (CFTR), the defective protein in cystic fibrosis, is the region of the channel that regulates the CFTR activity with multiple phosphorylation sites. This domain is an intrinsically disordered protein, characterized by lack of stable or unique tertiary structure. The disordered character of a protein is directly correlated with its function. The flexibility of RD may be important for its regulatory role: the continuous conformational change may be necessary for the progressive phosphorylation, and thus activation, of the channel. However, the lack of a defined and stable structure results in a considerable limitation when trying to in build a unique molecular model for the RD. Moreover, several evidences indicate significant structural differences between the native, non-phosphorylated state, and the multiple phosphorylated state of the protein. The aim of our work is to provide data to describe the conformations and the thermodynamic properties in these two functional states of RD. We have done the circular dichroism (CD) spectra in samples with a different degree of phosphorylation, from the non-phosphorylated state to a bona fide completely phosphorylated state. Analysis of CD spectra showed that the random coil and {beta}-sheets secondary structure decreased with the polypeptide phosphorylation, at expenses of an increase of {alpha}-helix. This observation lead to interpret phosphorylation as a mechanism favoring a more structured state. We also studied the thermal denaturation curves of the protein in the two

  15. Thermodynamic study of the native and phosphorylated regulatory domain of the CFTR

    International Nuclear Information System (INIS)

    Highlights: ► CFTR mutations produce cystic fibrosis. ► Chloride transport depends on the regulatory domain phosphorylation. ► Regulatory domain is intrinsically disordered. ► Secondary structure and protein stability change upon phosphorylation. -- Abstract: The regulatory domain (RD) of the cystic fibrosis transmembrane conductance regulator (CFTR), the defective protein in cystic fibrosis, is the region of the channel that regulates the CFTR activity with multiple phosphorylation sites. This domain is an intrinsically disordered protein, characterized by lack of stable or unique tertiary structure. The disordered character of a protein is directly correlated with its function. The flexibility of RD may be important for its regulatory role: the continuous conformational change may be necessary for the progressive phosphorylation, and thus activation, of the channel. However, the lack of a defined and stable structure results in a considerable limitation when trying to in build a unique molecular model for the RD. Moreover, several evidences indicate significant structural differences between the native, non-phosphorylated state, and the multiple phosphorylated state of the protein. The aim of our work is to provide data to describe the conformations and the thermodynamic properties in these two functional states of RD. We have done the circular dichroism (CD) spectra in samples with a different degree of phosphorylation, from the non-phosphorylated state to a bona fide completely phosphorylated state. Analysis of CD spectra showed that the random coil and β-sheets secondary structure decreased with the polypeptide phosphorylation, at expenses of an increase of α-helix. This observation lead to interpret phosphorylation as a mechanism favoring a more structured state. We also studied the thermal denaturation curves of the protein in the two conditions, monitoring the changes of the mean residue ellipticity measured at 222 nm as a function of temperature

  16. Depleted uranium in Japan

    International Nuclear Information System (INIS)

    In Japan, depleted uranium ammunition is regarded as nuclear weapons and meets with fierce opposition. The fact that US Marines mistakenly fired bullets containing depleted uranium on an island off Okinawa during training exercises in December 1995 and January 1996, also contributes. The overall situation in this area in Japan is outlined. (P.A.)

  17. Water Depletion Threatens Agriculture

    Science.gov (United States)

    Brauman, K. A.; Richter, B. D.; Postel, S.; Floerke, M.; Malsy, M.

    2014-12-01

    Irrigated agriculture is the human activity that has by far the largest impact on water, constituting 85% of global water consumption and 67% of global water withdrawals. Much of this water use occurs in places where water depletion, the ratio of water consumption to water availability, exceeds 75% for at least one month of the year. Although only 17% of global watershed area experiences depletion at this level or more, nearly 30% of total cropland and 60% of irrigated cropland are found in these depleted watersheds. Staple crops are particularly at risk, with 75% of global irrigated wheat production and 65% of irrigated maize production found in watersheds that are at least seasonally depleted. Of importance to textile production, 75% of cotton production occurs in the same watersheds. For crop production in depleted watersheds, we find that one half to two-thirds of production occurs in watersheds that have not just seasonal but annual water shortages, suggesting that re-distributing water supply over the course of the year cannot be an effective solution to shortage. We explore the degree to which irrigated production in depleted watersheds reflects limitations in supply, a byproduct of the need for irrigation in perennially or seasonally dry landscapes, and identify heavy irrigation consumption that leads to watershed depletion in more humid climates. For watersheds that are not depleted, we evaluate the potential impact of an increase in irrigated production. Finally, we evaluate the benefits of irrigated agriculture in depleted and non-depleted watersheds, quantifying the fraction of irrigated production going to food production, animal feed, and biofuels.

  18. Characterization of mitochondrial function in cells with impaired cystic fibrosis transmembrane conductance regulator (CFTR) function.

    Science.gov (United States)

    Atlante, Anna; Favia, Maria; Bobba, Antonella; Guerra, Lorenzo; Casavola, Valeria; Reshkin, Stephan Joel

    2016-06-01

    Evidence supporting the occurrence of oxidative stress in Cystic Fibrosis (CF) is well established and the literature suggests that oxidative stress is inseparably linked to mitochondrial dysfunction. Here, we have characterized mitochondrial function, in particular as it regards the steps of oxidative phosphorylation and ROS production, in airway cells either homozygous for the F508del-CFTR allele or stably expressing wt-CFTR. We find that oxygen consumption, ΔΨ generation, adenine nucleotide translocator-dependent ADP/ATP exchange and both mitochondrial Complex I and IV activities are impaired in CF cells, while both mitochondrial ROS production and membrane lipid peroxidation increase. Importantly, treatment of CF cells with the small molecules VX-809 and 4,6,4'-trimethylangelicin, which act as "correctors" for F508del CFTR by rescuing the F508del CFTR-dependent chloride secretion, while having no effect per sè on mitochondrial function in wt-CFTR cells, significantly improved all the above mitochondrial parameters towards values found in the airway cells expressing wt-CFTR. This novel study on mitochondrial bioenergetics provides a springboard for future research to further understand the molecular mechanisms responsible for the involvement of mitochondria in CF and identify the proteins primarily responsible for the F508del-CFTR-dependent mitochondrial impairment and thus reveal potential novel targets for CF therapy. PMID:27146408

  19. Optimizing nasal potential difference analysis for CFTR modulator development: assessment of ivacaftor in CF subjects with the G551D-CFTR mutation.

    Directory of Open Access Journals (Sweden)

    Steven M Rowe

    Full Text Available Nasal potential difference (NPD is used as a biomarker of the cystic fibrosis transmembrane conductance regulator (CFTR and epithelial sodium channel (ENaC activity. We evaluated methods to detect changes in chloride and sodium transport by NPD based on a secondary analysis of a Phase II CFTR-modulator study. Thirty-nine subjects with CF who also had the G551D-CFTR mutation were randomized to receive ivacaftor (Kalydeco™; also known as VX-770 in four doses or placebo twice daily for at least 14 days. All data were analyzed by a single investigator who was blinded to treatment assignment. We compared three analysis methods to determine the best approach to quantify changes in chloride and sodium transport: (1 the average of both nostrils; (2 the most-polarized nostril at each visit; and (3 the most-polarized nostril at screening carried forward. Parameters of ion transport included the PD change with zero chloride plus isoproterenol (CFTR activity, the basal PD, Ringer's PD, and change in PD with amiloride (measurements of ENaC activity, and the delta NPD (measuring CFTR and ENaC activity. The average and most-polarized nostril at each visit were most sensitive to changes in chloride and sodium transport, whereas the most-polarized nostril at screening carried forward was less discriminatory. Based on our findings, NPD studies should assess both nostrils rather than a single nostril. We also found that changes in CFTR activity were more readily detected than changes in ENaC activity, and that rigorous standardization was associated with relatively good within-subject reproducibility in placebo-treated subjects (± 2.8 mV. Therefore, we have confirmed an assay of reasonable reproducibility for detecting chloride-transport improvements in response to CFTR modulation.

  20. Activation Effect of Cathartic Natural Compound Rhein to CFTR Chloride Channel

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-activated chloride channel expressed in intestinal exocrine glands, which plays a key role in intestinal fluid secretion. A natural anthraquinone activator of CFTR Cl- channel, rhein, was identified by screening 217 single compounds from Chinese herbs via a cellbased halide-sensitive fluorescent assay. Rhein activates CFTR Cl- transportation in a dose-dependent manner in the presence of cAMP with a physiological concentration. This study provides a novel molecular pharmacological mechanism for the laxative drugs in Traditional Chinese Medicine such as aloe, cascara and senna.

  1. Assessment of the depletion capability in MPACT

    International Nuclear Information System (INIS)

    The objective of the paper is to develop and demonstrate the depletion capability with pin resolved transport using the MPACT code. The first section of the paper provides a description of the depletion methodology and the algorithm used to solve the depletion equations in MPACT. A separate depletion library for MPACT is used based on the ORIGEN-S library to provide the basic decay constants and fission yields, as well as the 3-group cross-sections which are used for the isotopes not contained in the MPACT multi-group library. The cross sections for the depletion transmutation matrix were collapsed using the transport flux solution in MPACT based on either the 47 group HELIOS library based on ENDF-VI or a 56 group ORNL library based on ENDF-VII. The second section of this paper then describes the numerical verification of the depletion algorithm using two sets of benchmarks. The first is the JAERI LWR lattice benchmark which had participants from most of the lattice depletion codes currently used in the international nuclear community and the second benchmark is based on data from spent fuel of the Takahama-3 reactor. The results show that MPACT is generally in good agreement with the results of the other benchmark participants as well as the experimental data. Finally, a full core 2D model of CASL AMA benchmark was depleted based on the central plane of the Watts Bar reactor core which demonstrates the whole core depletion capability of MPACT. (author)

  2. The analysis of some CFTR gene mutations in a small group of cf patients from southern part of Romania

    Directory of Open Access Journals (Sweden)

    Lucian GAVRILA

    2009-05-01

    Full Text Available Cystic fibrosis is the most common hereditary disease in European descendant populations, with prevalencedepending on ethnic groups studied. In contrast to other European countries, there is little information regarding the frequency ofCFTR mutations for the Southern part of Romania. The aim of this study was to test the presence of nine CFTR mutations in CFpatients from the Southern part of Romania, using complementary analysis methods. We investigated a group of unrelated CFpatients (n=19 and, when possible, their voluntary parents (n=15. We observed that the most frequently worldwide CF mutation,delta F508, was present in 17 of our patients (89.5% in homozygous (n=7 or heterozygous (n=10 condition and absent in 2 cases(10.5%. This mutation was also detected in ten parents, seven of them (100% have homozygous children and three (37.5%have heterozygous children for delta F508 mutation. None of the G542X, S549N, G551D, R553X, R560T, S1255X, W1282X andN1303K mutations have been detected in the samples from patients or parents. Our results are partially similar with those reportedin neighbouring countries where the delta F508 is the most common mutation detected and the frequency of R560T, S549N, G551D andS1255X mutations is near zero. The enlargement of this study could give a better result regarding the spectrum of CFTR mutationsin Romanian patients with CF.

  3. Potentiation of ΔF508- and G551D-CFTR-Mediated Cl- Current by Novel Hydroxypyrazolines.

    Science.gov (United States)

    Park, Jinhong; Khloya, Poonam; Seo, Yohan; Kumar, Satish; Lee, Ho K; Jeon, Dong-Kyu; Jo, Sungwoo; Sharma, Pawan K; Namkung, Wan

    2016-01-01

    The most common mutation of CFTR, affecting approximately 90% of CF patients, is a deletion of phenylalanine at position 508 (F508del, ΔF508). Misfolding of ΔF508-CFTR impairs both its trafficking to the plasma membrane and its chloride channel activity. To identify small molecules that can restore channel activity of ΔF508-CFTR, we synthesized and evaluated eighteen novel hydroxypyrazoline analogues as CFTR potentiators. To elucidate potentiation activities of hydroxypyrazolines for ΔF508-CFTR, CFTR activity was measured using a halide-sensitive YFP assay, Ussing chamber assay and patch-clamp technique. Compounds 7p, 7q and 7r exhibited excellent potentiation with EC50 value <10 μM. Among the compounds, 7q (a novel CFTR potentiator, CP7q) showed the highest potentiation activity with EC50 values of 0.88 ± 0.11 and 4.45 ± 0.31 μM for wild-type and ΔF508-CFTR, respectively. In addition, CP7q significantly potentiated chloride conductance of G551D-CFTR, a CFTR gating mutant; its maximal potentiation activity was 1.9 fold higher than the well-known CFTR potentiator genistein. Combination treatment with CP7q and VX-809, a corrector of ΔF508-CFTR, significantly enhanced functional rescue of ΔF508-CFTR compared with VX-809 alone. CP7q did not alter the cytosolic cAMP level and showed no cytotoxicity at the concentration showing maximum efficacy. The hydroxypyrazolines may be potential development candidates for drug therapy of cystic fibrosis. PMID:26863533

  4. Potentiation of ΔF508- and G551D-CFTR-Mediated Cl- Current by Novel Hydroxypyrazolines.

    Directory of Open Access Journals (Sweden)

    Jinhong Park

    Full Text Available The most common mutation of CFTR, affecting approximately 90% of CF patients, is a deletion of phenylalanine at position 508 (F508del, ΔF508. Misfolding of ΔF508-CFTR impairs both its trafficking to the plasma membrane and its chloride channel activity. To identify small molecules that can restore channel activity of ΔF508-CFTR, we synthesized and evaluated eighteen novel hydroxypyrazoline analogues as CFTR potentiators. To elucidate potentiation activities of hydroxypyrazolines for ΔF508-CFTR, CFTR activity was measured using a halide-sensitive YFP assay, Ussing chamber assay and patch-clamp technique. Compounds 7p, 7q and 7r exhibited excellent potentiation with EC50 value <10 μM. Among the compounds, 7q (a novel CFTR potentiator, CP7q showed the highest potentiation activity with EC50 values of 0.88 ± 0.11 and 4.45 ± 0.31 μM for wild-type and ΔF508-CFTR, respectively. In addition, CP7q significantly potentiated chloride conductance of G551D-CFTR, a CFTR gating mutant; its maximal potentiation activity was 1.9 fold higher than the well-known CFTR potentiator genistein. Combination treatment with CP7q and VX-809, a corrector of ΔF508-CFTR, significantly enhanced functional rescue of ΔF508-CFTR compared with VX-809 alone. CP7q did not alter the cytosolic cAMP level and showed no cytotoxicity at the concentration showing maximum efficacy. The hydroxypyrazolines may be potential development candidates for drug therapy of cystic fibrosis.

  5. Relationships among CFTR expression, HCO3- secretion, and host defense may inform gene- and cell-based cystic fibrosis therapies.

    Science.gov (United States)

    Shah, Viral S; Ernst, Sarah; Tang, Xiao Xiao; Karp, Philip H; Parker, Connor P; Ostedgaard, Lynda S; Welsh, Michael J

    2016-05-10

    Cystic fibrosis (CF) is caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel. Airway disease is the major source of morbidity and mortality. Successful implementation of gene- and cell-based therapies for CF airway disease requires knowledge of relationships among percentages of targeted cells, levels of CFTR expression, correction of electrolyte transport, and rescue of host defense defects. Previous studies suggested that, when ∼10-50% of airway epithelial cells expressed CFTR, they generated nearly wild-type levels of Cl(-) secretion; overexpressing CFTR offered no advantage compared with endogenous expression levels. However, recent discoveries focused attention on CFTR-mediated HCO3 (-) secretion and airway surface liquid (ASL) pH as critical for host defense and CF pathogenesis. Therefore, we generated porcine airway epithelia with varying ratios of CF and wild-type cells. Epithelia with a 50:50 mix secreted HCO3 (-) at half the rate of wild-type epithelia. Likewise, heterozygous epithelia (CFTR(+/-) or CFTR(+/∆F508)) expressed CFTR and secreted HCO3 (-) at ∼50% of wild-type values. ASL pH, antimicrobial activity, and viscosity showed similar relationships to the amount of CFTR. Overexpressing CFTR increased HCO3 (-) secretion to rates greater than wild type, but ASL pH did not exceed wild-type values. Thus, in contrast to Cl(-) secretion, the amount of CFTR is rate-limiting for HCO3 (-) secretion and for correcting host defense abnormalities. In addition, overexpressing CFTR might produce a greater benefit than expressing CFTR at wild-type levels when targeting small fractions of cells. These findings may also explain the risk of airway disease in CF carriers. PMID:27114540

  6. Uses of depleted uranium

    International Nuclear Information System (INIS)

    The depleted uranium is that in which percentage of uranium-235 fission executable is less than 0.2% or 0.3%. It is usually caused by the process of reprocessing the nuclear fuel burning, and also mixed with some other radioactive elements such as uranium 236, 238 and plutonium 239. The good features of the depleted uranium are its high density, low price and easily mined. So, the specifications for depleted uranium make it one of the best materials in case you need to have objects small in size, but quite heavy regarding its size. Uses of deplet ed uranium were relatively increased in domestic industrial uses as well as some uses in nuclear industry in the last few years. So it has increased uses in many areas of military and peaceful means such as: in balancing the giant air crafts, ships and missiles and in the manufacture of some types of concrete with severe hardness. (author)

  7. Study on occurrence of the IVS8-5T allele of the CFTR gene in Ukrainian males with spermatogenesis failure

    Directory of Open Access Journals (Sweden)

    Zinchenko V. M.

    2010-07-01

    Full Text Available Aim. To study the IVS8-5T allele of the CFTR gene and it is involvement in spermatogenesis failure in men with azoospermia and oligozoospermia. Methods. The IVS8-nT polymorphism was analyzed by PCR followed by «A.L.F.-express» fragment analysis in the infertile men group, consisting of 113 azoospermic and 217 oligozoospermic patients, and the control group of 150 fertile men with proven paternity. Results. The frequency of the IVS8-5T allele among infertile males was higher than in controls. A statistically significant difference (P < 0.05 was observed in the frequencies of the IVS8-5T allele in azoospermia patients (5.3 % when compared with the control group (2.0 %. Conclusions. The IVS8-5T allele of the CFTR gene contributes to spermatogenesis failure and/or sperm maturation.

  8. CFTR is required for maximal transepithelial liquid transport in pig alveolar epithelia

    OpenAIRE

    Li, Xiaopeng; Comellas, Alejandro P.; Karp, Philip H.; Ernst, Sarah E.; Moninger, Thomas O.; Gansemer, Nicholas D.; Taft, Peter J.; Pezzulo, Alejandro A; Michael V Rector; Rossen, Nathan; Stoltz, David A.; McCray, Paul B.; Welsh, Michael J.; Zabner, Joseph

    2012-01-01

    A balance between alveolar liquid absorption and secretion is critical for maintaining optimal alveolar subphase liquid height and facilitating gas exchange in the alveolar space. However, the role of cystic fibrosis transmembrane regulator protein (CFTR) in this homeostatic process has remained elusive. Using a newly developed porcine model of cystic fibrosis, in which CFTR is absent, we investigated ion transport properties and alveolar liquid transport in isolated type II alveolar epitheli...

  9. Physiological Adaptation of the Bacterium Lactococcus lactis in Response to the Production of Human CFTR*

    OpenAIRE

    A. Steen; Wiederhold, E.; T Gandhi; Breitling, R.; D. J. Slotboom

    2010-01-01

    Biochemical and biophysical characterization of CFTR (the cystic fibrosis transmembrane conductance regulator) is thwarted by difficulties to obtain sufficient quantities of correctly folded and functional protein. Here we have produced human CFTR in the prokaryotic expression host Lactococcus lactis. The full-length protein was detected in the membrane of the bacterium, but the yields were too low (< 0.1% of membrane proteins) for in vitro functional and structural characterization, and indu...

  10. Adeno-associated virus–targeted disruption of the CFTR gene in cloned ferrets

    OpenAIRE

    Sun, Xingshen; Yan, Ziying; Yi, Yaling; Li, Ziyi; Lei, Diana; Rogers, Christopher S.; Chen, Juan; Zhang, Yulong; Welsh, Michael J.; Leno, Gregory H.; Engelhardt, John F.

    2008-01-01

    Somatic cell gene targeting combined with nuclear transfer cloning presents tremendous potential for the creation of new, large-animal models of human diseases. Mouse disease models often fail to reproduce human phenotypes, underscoring the need for the generation and study of alternative disease models. Mice deficient for CFTR have been poor models for cystic fibrosis (CF), lacking many aspects of human CF lung disease. In this study, we describe the production of a CFTR gene–deficient model...

  11. Phenotypic variability of R117H-CFTR expression within monozygotic twins.

    Science.gov (United States)

    Waller, Michael D; Simmonds, Nicholas J

    2016-08-01

    Whilst cystic fibrosis is a monogenic condition, variation in phenotype exists for the same CFTR genotype, which is influenced by multiple genetic and non-genetic (environmental) factors. The R117H-CFTR mutation has variability directly relating to in cis poly-thymidine alleles, producing a differing spectrum of disease. This paper provides evidence of extreme phenotype variability - including fertility status - in the context of male monogenetic twins, discussing mechanisms and highlighting the diagnostic and treatment challenges. PMID:27364092

  12. Refining the continuum of CFTR-associated disorders in the era of newborn screening.

    Science.gov (United States)

    Levy, H; Nugent, M; Schneck, K; Stachiw-Hietpas, D; Laxova, A; Lakser, O; Rock, M; Dahmer, M K; Biller, J; Nasr, S Z; Baker, M; McColley, S A; Simpson, P; Farrell, P M

    2016-05-01

    Clinical heterogeneity in cystic fibrosis (CF) often causes diagnostic uncertainty in infants without symptoms and in older patients with milder phenotypes. We performed a cross-sectional evaluation of a comprehensive set of clinical and laboratory descriptors in a physician-defined cohort (N = 376; Children's Hospital of Wisconsin and the American Family Children's Hospital CF centers in Milwaukee and Madison, WI, USA) to determine the robustness of categorizing CF (N = 300), cystic fibrosis transmembrane conductance regulator (CFTR)-related disorder (N = 19), and CFTR-related (CRMS) metabolic syndrome (N = 57) according to current consensus guidelines. Outcome measures included patient demographics, clinical measures, sweat chloride levels, CFTR genotype, age at diagnosis, airway microbiology, pancreatic function, infection, and nutritional status. The CF cohort had a significantly higher median sweat chloride level (105 mmol/l) than CFTR-related disorder patients (43 mmol/l) and CFTR-related metabolic syndrome patients (35 mmol/l; p ≤ 0.001). Patient groups significantly differed in pancreatic sufficiency, immunoreactive trypsinogen levels, sweat chloride values, genotype, and positive Pseudomonas aeruginosa cultures (p ≤ 0.001). An automated classification algorithm using recursive partitioning demonstrated concordance between physician diagnoses and consensus guidelines. Our analysis suggests that integrating clinical information with sweat chloride levels, CFTR genotype, and pancreatic sufficiency provides a context for continued longitudinal monitoring of patients for personalized and effective treatment. PMID:26671754

  13. Synthesis and Characterization of A Small Molecule CFTR Chloride Channel Inhibitor

    Institute of Scientific and Technical Information of China (English)

    HE Cheng-yan; ZHANG Heng-jun; SU Zhong-min; ZHOU Jin-song; YANG Hong; MA Tong-hui

    2004-01-01

    A thiazolidinone CFTR inhibitor(CFTRinh-172) was synthesized by a three-step procedure with trifluromethylaniline as the starting material. The synthesized CFTR inhibitor was characterized structurally by means of 1H NMR and functionally in a CFTR-expressing cell line FRT/hCFTR/EYFP-H148Q by both fluorescent and electrophysiological methods. A large amount(100 g) of high-quality small molecule thiazolidinone CFTR chloride channel inhibitor, CFTRinh-172, can be produced with this simple three-step synthetic procedure. The structure of the final product 2-thioxo-3-(3-trifluromethylphenyl)-5-[4-carboxyphenyl-methylene]-4-thiazolidinone was confirmed by 1H NMR. The overall yield was 58% with a purity over 99% as analyzed by HPLC. The synthesized CFTRinh-172 specifically inhibited CFTR chloride channel function in a cell-based fluorescence assay(Kd≈1.5 μmol/L) and in a Ussing chamber-based short-circuit current assay(Kd≈0.2 μmol/L), indicating better quality than that of the commercial combinatorial compound. The synthesized inhibitor is nontoxic to cultured cells at a high concentration and to mouse at a high dose. The synthetic procedure developed here can be used to produce a large amount of the high-quality CFTRinh-172 suitable for antidiarrheal studies and for creation of cystic fibrosis models in large animals. The procedure can be used to synthesize radiolabled CFTRinh-172 for in vivo pharmacokinetics studies.

  14. Facilitating Structure-Function Studies of CFTR Modulator Sites with Efficiencies in Mutagenesis and Functional Screening.

    Science.gov (United States)

    Molinski, Steven V; Ahmadi, Saumel; Hung, Maurita; Bear, Christine E

    2015-12-01

    There are nearly 2000 mutations in the CFTR gene associated with cystic fibrosis disease, and to date, the only approved drug, Kalydeco, has been effective in rescuing the functional expression of a small subset of these mutant proteins with defects in channel activation. However, there is currently an urgent need to assess other mutations for possible rescue by Kalydeco, and further, definition of the binding site of such modulators on CFTR would enhance our understanding of the mechanism of action of such therapeutics. Here, we describe a simple and rapid one-step PCR-based site-directed mutagenesis method to generate mutations in the CFTR gene. This method was used to generate CFTR mutants bearing deletions (p.Gln2_Trp846del, p.Ser700_Asp835del, p.Ile1234_Arg1239del) and truncation with polyhistidine tag insertion (p.Glu1172-3Gly-6-His*), which either recapitulate a disease phenotype or render tools for modulator binding site identification, with subsequent evaluation of drug responses using a high-throughput (384-well) membrane potential-sensitive fluorescence assay of CFTR channel activity within a 1 wk time frame. This proof-of-concept study shows that these methods enable rapid and quantitative comparison of multiple CFTR mutants to emerging drugs, facilitating future large-scale efforts to stratify mutants according to their "theratype" or most promising targeted therapy. PMID:26385858

  15. Lack of CFTR in Skeletal Muscle Predisposes to Muscle Wasting and Diaphragm Muscle Pump Failure in Cystic Fibrosis Mice

    OpenAIRE

    Maziar Divangahi; Haouaria Balghi; Gawiyou Danialou; Comtois, Alain S.; Alexandre Demoule; Sheila Ernest; Christina Haston; Renaud Robert; Hanrahan, John W.; Danuta Radzioch; Petrof, Basil J

    2009-01-01

    Cystic fibrosis (CF) patients often have reduced mass and strength of skeletal muscles, including the diaphragm, the primary muscle of respiration. Here we show that lack of the CF transmembrane conductance regulator (CFTR) plays an intrinsic role in skeletal muscle atrophy and dysfunction. In normal murine and human skeletal muscle, CFTR is expressed and co-localized with sarcoplasmic reticulum-associated proteins. CFTR-deficient myotubes exhibit augmented levels of intracellular calcium aft...

  16. Defective CFTR expression and function are detectable in blood monocytes : development of a new blood test for cystic fibrosis

    OpenAIRE

    Sorio, C.; Buffelli, M.; C. Angiari; Ettorre, M; Johansson, J; M. Vezzalini; Viviani, L; Ricciardi, M.; G. Verzè; Assael, B M; P. Melotti

    2011-01-01

    Background Evaluation of cystic fibrosis transmembrane conductance regulator (CFTR) functional activity to assess new therapies and define diagnosis of cystic fibrosis (CF) is cumbersome. It is known that leukocytes express detectable levels of CFTR but the molecule has not been characterized in these cells. In this study we aim at setting up and validating a blood test to evaluate CFTR expression and function in leukocytes. Description Western blot, PCR, immunofluorescence and cell membrane ...

  17. Development of allele-specific multiplex PCR to determine the length of poly-T in intron 8 of CFTR

    OpenAIRE

    Neng Chen; Prada, Anne E.

    2014-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation analysis has been implemented for Cystic Fibrosis (CF) carrier screening, and molecular diagnosis of CF and congenital bilateral absence of the vas deferens (CBAVD). Although poly-T allele analysis in intron 8 of CFTR is required when a patient is positive for R117H, it is not recommended for routine carrier screening. Therefore, commercial kits for CFTR mutation analysis were designed either to mask the poly-T allele re...

  18. miR-16 rescues F508del-CFTR function in native cystic fibrosis epithelial cells.

    Science.gov (United States)

    Kumar, P; Bhattacharyya, S; Peters, K W; Glover, M L; Sen, A; Cox, R T; Kundu, S; Caohuy, H; Frizzell, R A; Pollard, H B; Biswas, R

    2015-11-01

    Cystic fibrosis (CF) is due to mutations in the CFTR gene, which prevents correct folding, trafficking and function of the mutant cystic fibrosis transmembrane conductance regulator (CFTR) protein. The dysfunctional effect of CFTR mutations, principally the F508del-CFTR mutant, is further manifested by hypersecretion of the pro-inflammatory chemokine interleukin-8 into the airway lumen, which further contributes to morbidity and mortality. We have hypothesized that microRNA (miR)-based therapeutics could rescue the dysfunctional consequences of mutant CFTR. Here we report that a miR-16 mimic can effectively rescue F508del-CFTR protein function in airway cell lines and primary cultures, of differentiated human bronchial epithelia from F508del homozygotes, which express mutant CFTR endogenously. We also identify two other miRs, miR-1 and miR-302a, which are also active. Although miR-16 is expressed at basal comparable levels in CF and control cells, miR-1 and miR-302a are undetectable. When miR mimics are expressed in CF lung or pancreatic cells, the expression of the F508del-CFTR protein is significantly increased. Importantly, miR-16 promotes functional rescue of the cyclic AMP-activated apical F508del-CFTR chloride channel in primary lung epithelial cells from CF patients. We interpret these findings to suggest that these miRs may constitute novel targets for CF therapy. PMID:26133785

  19. The Chemistry and Toxicology of Depleted Uranium

    Directory of Open Access Journals (Sweden)

    Sidney A. Katz

    2014-03-01

    Full Text Available Natural uranium is comprised of three radioactive isotopes: 238U, 235U, and 234U. Depleted uranium (DU is a byproduct of the processes for the enrichment of the naturally occurring 235U isotope. The world wide stock pile contains some 1½ million tons of depleted uranium. Some of it has been used to dilute weapons grade uranium (~90% 235U down to reactor grade uranium (~5% 235U, and some of it has been used for heavy tank armor and for the fabrication of armor-piercing bullets and missiles. Such weapons were used by the military in the Persian Gulf, the Balkans and elsewhere. The testing of depleted uranium weapons and their use in combat has resulted in environmental contamination and human exposure. Although the chemical and the toxicological behaviors of depleted uranium are essentially the same as those of natural uranium, the respective chemical forms and isotopic compositions in which they usually occur are different. The chemical and radiological toxicity of depleted uranium can injure biological systems. Normal functioning of the kidney, liver, lung, and heart can be adversely affected by depleted uranium intoxication. The focus of this review is on the chemical and toxicological properties of depleted and natural uranium and some of the possible consequences from long term, low dose exposure to depleted uranium in the environment.

  20. Antarctic ozone depletion

    International Nuclear Information System (INIS)

    Antarctic ozone depletion is most severe during the southern hemisphere spring, when the local reduction in the column amount may be as much as 50 percent. The extent to which this ozone poor air contributes to the observed global ozone loss is a matter of debate, but there is some evidence that fragments of the 'ozone hole' can reach lower latitudes following its breakup in summer. Satellite data show the seasonal evolution of the ozone hole. A new dimension has been added to Antarctic ozone depletion with the advent of large volcanic eruptions such as that from Mount Pinatubo in 1991. (author). 5 refs., 1 fig

  1. Enhancement and depletion of lower/middle tropospheric ozone in Senegal during pre-monsoon and monsoon periods of summer 2008: observations and model results

    Directory of Open Access Journals (Sweden)

    G. S. Jenkins

    2011-10-01

    Full Text Available During the summer (8 June through 3 September of 2008, 9 ozonesondes are launched from Dakar, Senegal (14.75° N, 17.49° W to investigate ozone (O3 variability in the lower/middle troposphere during the pre-monsoon and monsoon periods. Results during June 2008 (pre-monsoon period show a reduction in O3 concentrations, especially in the 850–700 hPa layer with Saharan Air Layer (SAL events. However, O3 concentrations are increased in the 950–900 hPa layer where the peak of the inversion is found and presumably the highest dust concentrations. We also use the WRF-CHEM model to gain greater insights for observations of elevated/reduced O3 concentrations during the pre-monsoon/monsoon periods. In the transition period between 26 June and 2 July in the lower troposphere (925–600 hPa, a significant increase in O3 concentrations occur which we suggest is caused by enhanced biogenic NOx emissions from Sahelian soils following rain events on 28 June and 1 July. During July and August 2008 (monsoon period, with the exception of one SAL outbreak, vertical profiles of O3 are well mixed with concentrations not exceeding 55 ppb between the surface and 550 hPa. The results suggest that during the pre-monsoon period ozone concentrations in the lower troposphere are controlled by the SAL, which destroys ozone through heterogeneous processes. At the base of the SAL we also find elevated levels of ozone, which we attribute to biogenic sources of NOx from Saharan dust that are released in the presence of moist conditions. Once the monsoon period commences, wet and dry deposition become important sinks of ozone in the Sahel with episodes of ozone poor air that is horizontally transported from low latitudes into the Sahel. These results support aircraft chemical measurements and chemical modeling results from the African Monsoon Multidisciplinary Analysis (AMMA field

  2. Deuterium - depleted water. Achievements and perspectives

    International Nuclear Information System (INIS)

    reproduction of fish with deuterium - depleted water fecundated solutions confirmed favourable influence in embryo growth stage and resistance in next growth stages; 5. it was studied germination, growth and quantitative character's variability in plants; one can remark the favourable influence of deuterium - depleted water on biological process in plants in various ontogenetic stages; 6. the deuterium depletion in seawater produces the diminution of the water spectral energy related to an increased metabolism of Tetraselmis suecica. Although the results obtained in Romania have a special scientific value, the application of these researches is in progress. We have to mention that at present all the amount of deuterium - depleted water produced at Rm. Valcea is exported to Hungary were it is used to produce drugs for the prevention and the treatment of cancer. (authors)

  3. Willpower depletion and framing effects

    OpenAIRE

    de Haan, Thomas; van Veldhuizen, Roel

    2013-01-01

    We investigate whether depleting people's cognitive resources (or willpower) affects the degree to which they are susceptible to framing effects. Recent research in social psychology and economics has suggested that willpower is a resource that can be temporarily depleted and that a depleted level of willpower is associated with self-control problems in a variety of contexts. In this study, we extend the willpower depletion paradigm to framing effects and argue that willpower depletion should...

  4. Haploidentical Transplantation Without In Vitro T-Cell Depletion Results in Outcomes Equivalent to Those of Contemporaneous Matched Sibling and Unrelated Donor Transplantation for Acute Leukemia.

    Science.gov (United States)

    Yu, Sijian; Fan, Qian; Sun, Jing; Fan, Zhiping; Zhang, Yu; Jiang, Qianli; Huang, Fen; Xuan, Li; Dai, Min; Zhou, Hongsheng; Liu, Hui; Liu, Qi-Fa

    2016-03-01

    The aim of the study is to determine whether HLA-haploidentical-related donor (HRD) transplant can achieve equivalent outcomes and have stronger GVL compared to HLA-matched sibling donor (MSD) and HLA-matched unrelated donor (MUD) transplants.A total of 355 consecutive patients with acute leukemia undergoing allogeneic transplant at our single institute between March 2008 and March 2014 were enrolled in this retrospective investigation.Of the 355 patients, 96 cases received HRD, 153 MSD, and 106 MUD transplants. HRD transplant was associated with higher incidences of grade II to IV aGVHD (40.6%) compared with MSD (23.5%, P = 0.002) and MUD transplants (34.0%, P = 0.049), whereas incidences of grade III to IV aGVHD (11.4%, 7.8%, 10.5%, respectively; P = 0.590) and cGVHD (29.5%, 24.0%, 29.5%, respectively; P = 0.538) did not differ among 3 groups. Five-year relapse rates were 19.2%, 26.8%, and 23.0% in 3 groups, respectively (P = 0.419). However, of 206 high-risk patients, the relapse rate in HRD transplant was lower than in MSD transplant (23.8% vs 41.9%, P = 0.026). Multivariate analysis showed that HRD had beneficial impact on relapse (for MSD: P = 0.006). Five-year transplant-related mortality was lower in MSD transplant compared with those in HRD (17.3% vs 26.4%, P = 0.041) and MUD transplants (17.3% vs 24.1%, P = 0.037). Five-year overall survival were 60.4%, 64.6%, and 61.0%, respectively, in HRD, MSD, and MUD groups (P = 0.371); 5-year disease-free survival were 59.6%, 58.8%, and 54.9%, respectively (P = 0.423).Our results suggest that HRD transplant results in outcomes equivalent to MSD and MUD transplants. HRD might carry a superior GVL effect compared to MSD for high-risk patients. PMID:26986108

  5. Enhancement and depletion of lower/middle tropospheric ozone in Senegal during pre-monsoon and monsoon periods of summer 2008: observations and model results

    Directory of Open Access Journals (Sweden)

    G. S. Jenkins

    2011-03-01

    Full Text Available During the summer (8 June through 3 September of 2008, nine ozonesondes are launched from Dakar, Senegal (14.75° N, 17.49° W to investigate the impact of the Saharan Dust Layer (SAL on ozone (O3 concentrations in the lower troposphere. Results during June (pre-monsoon period show a reduction in O3, especially in the 850–700 hPa layer with SAL events. However, O3 concentrations are increased in the 950–900 hPa layer where the peak of the inversion is found and presumably the highest dust concentrations. We use the WRF-CHEM model to explore the causes of elevated O3 concentrations that appear to have a stratospheric contribution. During July and August (monsoon period, with the exception of one SAL outbreak, vertical profiles of O3 are well mixed with concentrations not exceeding 55 ppb between the surface and 550 hPa. In the transition period between 26 June and 2 July lower tropospheric (925–600 hPa O3 concentrations are likely enhanced by enhanced biogenic NOx emissions from the Saharan desert and Sahelian soils following several rain events on 28 June and 1 July.

  6. Depletion of 4-hydroxynonenal in hGSTA4-transfected HLE B-3 cells results in profound changes in gene expression

    International Nuclear Information System (INIS)

    Previously, we have shown that overexpression of 4-hydroxy-2-nonenal (HNE)-detoxifying enzyme glutathione S-transferase A4-4 (hGSTA4-4) in human lens epithelial cells (HLE B-3) leads to pro-carcinogenic phenotypic transformation of these cells [R. Sharma, et al. Eur. J. Biochem. 271 (2004) 1960-1701]. We now demonstrate that hGSTA4-transfection also causes a profound change in the expression of genes involved in cell adhesion, cell cycle control, proliferation, cell growth, and apoptosis, which is consistent with phenotypic changes of the transformed cells. The expression of p53, p21, p16, fibronectin 1, laminin γ1, connexin 43, Fas, integrin α6, TGFα, and c-jun was down-regulated, while the expression of protein kinase C beta II (PKCβII), c-myc, cyclin-dependent kinase 2 (CDK2), and TGFβ was up-regulated in transfected cells. These results demonstrate that HNE serves as a crucial signaling molecule and, by modulating the expression of genes, can influence cellular functions

  7. Stratospheric ozone depletion.

    Science.gov (United States)

    Rowland, F Sherwood

    2006-05-29

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290-320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime-the 'Antarctic ozone hole'. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  8. Ozone Depletion from Nearby Supernovae

    CERN Document Server

    Gehrels, N; Jackman, C H; Cannizzo, J K; Mattson, B J; Chen, W; Gehrels, Neil; Laird, Claude M.; Jackman, Charles H.; Cannizzo, John K.; Mattson, Barbara J.; Chen, Wan

    2003-01-01

    Estimates made in the 1970's indicated that a supernova occurring within tens of parsecs of Earth could have significant effects on the ozone layer. Since that time, improved tools for detailed modeling of atmospheric chemistry have been developed to calculate ozone depletion, and advances have been made in theoretical modeling of supernovae and of the resultant gamma-ray spectra. In addition, one now has better knowledge of the occurrence rate of supernovae in the galaxy, and of the spatial distribution of progenitors to core-collapse supernovae. We report here the results of two-dimensional atmospheric model calculations that take as input the spectral energy distribution of a supernova, adopting various distances from Earth and various latitude impact angles. In separate simulations we calculate the ozone depletion due to both gamma-rays and cosmic rays. We find that for the combined ozone depletion roughly to double the ``biologically active'' UV flux received at the surface of the Earth, the supernova mu...

  9. Ozone Depletion from Nearby Supernovae

    Science.gov (United States)

    Gehrels, Neil; Laird, Claude M.; Jackman, Charles H.; Cannizzo, John K.; Mattson, Barbara J.; Chen, Wan; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    Estimates made in the 1970's indicated that a supernova occurring within tens of parsecs of Earth could have significant effects on the ozone layer. Since that time improved tools for detailed modeling of atmospheric chemistry have been developed to calculate ozone depletion, and advances have been made also in theoretical modeling of supernovae and of the resultant gamma ray spectra. In addition, one now has better knowledge of the occurrence rate of supernovae in the galaxy, and of the spatial distribution of progenitors to core-collapse supernovae. We report here the results of two-dimensional atmospheric model calculations that take as input the spectral energy distribution of a supernova, adopting various distances from Earth and various latitude impact angles. In separate simulations we calculate the ozone depletion due to both gamma rays and cosmic rays. We find that for the combined ozone depletion from these effects roughly to double the 'biologically active' UV flux received at the surface of the Earth, the supernova must occur at approximately or less than 8 parsecs.

  10. Rescue of NBD2 mutants N1303K and S1235R of CFTR by small-molecule correctors and transcomplementation.

    Directory of Open Access Journals (Sweden)

    Daniele Rapino

    Full Text Available Although, the most common Cystic Fibrosis mutation, ΔF508, in the cystic fibrosis transmembrane regulator. (CFTR, is located in nucleotide binding domain (NBD1, disease-causing mutations also occur in NBD2. To provide information on potential therapeutic strategies for mutations in NBD2, we studied, using a combination of biochemical approaches and newly created cell lines, two disease-causing NBD2 mutants, N1303K and S1235R. Surprisingly, neither was rescued by low temperature. Inhibition of proteasomes with MG132 or aggresomes with tubacin rescued the immature B and mature C bands of N1303K and S1235R, indicating that degradation occurs via proteasomes and aggresomes. We found no effect of the lysosome inhibitor E64. Thus, our results show that these NBD2 mutants are processing mutants with unique characteristics. Several known correctors developed to rescue ΔF508-CFTR, when applied either alone or in combination, significantly increased the maturation of bands B and C of both NBD 2 mutants. The best correction occurred with the combinations of C4 plus C18 or C3 plus C4. Co-transfection of truncated CFTR (∆27-264 into stably transfected cells was also able to rescue them. This demonstrates for the first time that transcomplementation with a truncated version of CFTR can rescue NBD2 mutants. Our results show that the N1303K mutation has a more profound effect on NBD2 processing than S1235R and that small-molecule correctors increase the maturation of bands B and C in NBD2 mutants. In addition, ∆27-264 was able to transcomplement both NDB2 mutants. We conclude that differences and similarities occur in the impact of mutations on NBD2 when compared to ΔF508-CFTR suggesting that individualized strategies may be needed to restore their function. Finally our results are important because they suggest that gene or corrector molecule therapies either alone or in combination individualized for NBD2 mutants may be beneficial for patients bearing

  11. Ubiquitination and Degradation of CFTR by the E3 Ubiquitin Ligase MARCH2 through Its Association with Adaptor Proteins CAL and STX6

    OpenAIRE

    Jie Cheng; William Guggino

    2013-01-01

    Golgi-localized cystic fibrosis transmembrane conductance regulator (CFTR)-associated ligand (CAL) and syntaxin 6 (STX6) regulate the abundance of mature, post-ER CFTR by forming a CAL/STX6/CFTR complex (CAL complex) that promotes CFTR degradation in lysosomes. However, the molecular mechanism underlying this degradation is unknown. Here we investigated the interaction of a Golgi-localized, membrane-associated RING-CH E3 ubiquitin ligase, MARCH2, with the CAL complex and the consequent bindin...

  12. Potentiators of Defective ΔF508-CFTR Gating that Do Not Interfere with Corrector Action.

    Science.gov (United States)

    Phuan, Puay-Wah; Veit, Guido; Tan, Joseph A; Finkbeiner, Walter E; Lukacs, Gergely L; Verkman, A S

    2015-10-01

    Combination drug therapies under development for cystic fibrosis caused by the ∆F508 mutation in cystic fibrosis transmembrane conductance regulator (CFTR) include a "corrector" to improve its cellular processing and a "potentiator" to improve its chloride channel function. Recently, it was reported that the approved potentiator N-(2,4-di-tert-butyl-5-hydroxyphenyl)-4-oxo-1,4-dihydroquinoline-3-carboxamide (Ivacaftor) reduces ∆F508-CFTR cellular stability and the efficacy of investigational correctors, including 3-(6-[([1-(2,2-difluoro-1,3-benzodioxol-5-yl)cyclopropyl]carbonyl) amino]-3-methyl-2-pyridinyl)-benzoic acid and 1-(2,2-difluoro-1,3-benzodioxol-5-yl)-N-(1-[(2R)-2,3-dihydroxypropyl]-6-fluoro-2-(2-hydroxy-1,1-dimethylethyl)-1H-indol-5-yl), which might contribute to the modest reported efficacy of combination therapy in clinical trials. Here, we report the identification and characterization of potentiators that do not interfere with ∆F508-CFTR stability or corrector action. High-throughput screening and structure-activity analysis identified several classes of potentiators that do not impair corrector action, including tetrahydrobenzothiophenes, thiooxoaminothiazoles, and pyrazole-pyrrole-isoxazoles. The most potent compounds have an EC(50) for ∆F508-CFTR potentiation down to 18 nM and do not reduce corrector efficacy in heterologous ∆F508-CFTR-expressing cells or primary cultures of ∆F508/∆F508 human bronchial epithelia. The ΔF508-CFTR potentiators also activated wild-type and G551D CFTR, albeit weakly. The efficacy of combination therapy for cystic fibrosis caused by the ∆F508 mutation may be improved by replacement of Ivacaftor with a potentiator that does not interfere with corrector action. PMID:26245207

  13. Depleted Uranium and Its Effects on Humans

    Directory of Open Access Journals (Sweden)

    Zdeněk Hon

    2015-04-01

    Full Text Available The article summarizes contemporary scientific knowledge of depleted uranium effects on human health due to its use in military conflicts. The discussion covers cases of minimal risk due to external irradiation resulting from the storage and handling of depleted uranium ammunition and, in contrast, important toxicological and radio-toxicological risks of late effects resulting from the inhalation and ingestion of dust particles produced by the burning of the core of the anti-tank ammunition.

  14. Depleted Uranium and Its Effects on Humans

    OpenAIRE

    Zdeněk Hon; Jan Österreicher; Leoš Navrátil

    2015-01-01

    The article summarizes contemporary scientific knowledge of depleted uranium effects on human health due to its use in military conflicts. The discussion covers cases of minimal risk due to external irradiation resulting from the storage and handling of depleted uranium ammunition and, in contrast, important toxicological and radio-toxicological risks of late effects resulting from the inhalation and ingestion of dust particles produced by the burning of the core of the anti-tank ammunition.

  15. A little CFTR goes a long way: CFTR-dependent sweat secretion from G551D and R117H-5T cystic fibrosis subjects taking ivacaftor.

    Directory of Open Access Journals (Sweden)

    Jessica E Char

    Full Text Available To determine if oral dosing with the CFTR-potentiator ivacaftor (VX-770, Kalydeco improves CFTR-dependent sweating in CF subjects carrying G551D or R117H-5T mutations, we optically measured sweat secretion from 32-143 individually identified glands in each of 8 CF subjects; 6 F508del/G551D, one G551D/R117H-5T, and one I507del/R117H-5T. Two subjects were tested only (- ivacaftor, 3 only (+ ivacaftor and 3 (+/- ivacaftor (1-5 tests per condition. The total number of gland measurements was 852 (- ivacaftor and 906 (+ ivacaftor. A healthy control was tested 4 times (51 glands. For each gland we measured both CFTR-independent (M-sweat and CFTR-dependent (C-sweat; C-sweat was stimulated with a β-adrenergic cocktail that elevated [cAMP]i while blocking muscarinic receptors. Absent ivacaftor, almost all CF glands produced M-sweat on all tests, but only 1/593 glands produced C-sweat (10 tests, 5 subjects. By contrast, 6/6 subjects (113/342 glands produced C-sweat in the (+ ivacaftor condition, but with large inter-subject differences; 3-74% of glands responded with C/M sweat ratios 0.04%-2.57% of the average WT ratio of 0.265. Sweat volume losses cause proportionally larger underestimates of CFTR function at lower sweat rates. The losses were reduced by measuring C/M ratios in 12 glands from each subject that had the highest M-sweat rates. Remaining losses were estimated from single channel data and used to correct the C/M ratios, giving estimates of CFTR function (+ ivacaftor  = 1.6%-7.7% of the WT average. These estimates are in accord with single channel data and transcript analysis, and suggest that significant clinical benefit can be produced by low levels of CFTR function.

  16. Correlation of the level of full-length CFTR transcript with pulmonary phenotype in patients carrying R117H and 1342-1,-2delAG mutations

    Energy Technology Data Exchange (ETDEWEB)

    Hamosh, A.; Cutting, G.R. [Johns Hopkins Univ. School of Medicine, Balitmore, MD (United States); Oates, R.; Amos, J. [Boston Univ. School of Medicine, Boston, MA (United States)

    1994-09-01

    The R117H mutation occurs on two chromosome backgrounds, one associated with a 7 thymidine tract (7T-R11H) in the splice-acceptor site of intron 8, the other with a 5 thymidine tract (5T-R117H). We examined exon 9 splicing efficiency in 5 patients of genotype R117H/{delta}F508 and one carrying 1342-1,-2delAG{delta}F508, an obligate exon 9 slice site mutation. Four patients carried R117H on a 7T background -- three adult men with congenital bilateral absence of the vas deferens and one adolescent female with pancreatitis and borderline sweat chloride concentration. The patient with R117H on a 5T background had pancreatic sufficient CF (PS-CF). The 1342-1,-2delAG patient has classic pancreatic insufficient CF (PI-CF). cDNA was synthesized from total RNA extracted from nasal epithlial cells and analyzed for CFTR splicing by 35 cycle PCR using primers in exon 7 and 11. The quantity of full length transcript derived from the R117H or {delta}F508 alleles was assessed by allele-specific oligonucleotide hybridization. While 91.4% of transcript from the 5T-R117H allele was full-length, only 42.2% of CFTR transcript from the 5T-R117H allele was full length. Since CBAVD patients have no lung disease and PS-CF patients do, this indicates that the threshold of developing CF lung disease is crossed when the amount of CFTR transcript bearing R117H is reduced by half. Interestingly, 17.1% of transcript derived from the 1342-1,-2delAG allele (or 8.6% of total CFTR transcript) was normal and full length. This suggests that up to 9% of full length wild-type CFTR transcript may be inadequate to escape the lung disease of CF and that a 9 thymidine tract followed by AAC (the result of the AG deletion) can be used as a splice donor with 2-9% efficiency.

  17. Children's Models of the Ozone Layer and Ozone Depletion.

    Science.gov (United States)

    Christidou, Vasilia; Koulaidis, Vasilis

    1996-01-01

    The views of 40 primary students on ozone and its depletion were recorded through individual, semi-structured interviews. The data analysis resulted in the formation of a limited number of models concerning the distribution and role of ozone in the atmosphere, the depletion process, and the consequences of ozone depletion. Identifies five target…

  18. Intrinsic Depletion or Not

    DEFF Research Database (Denmark)

    Klösgen, Beate; Bruun, Sara; Hansen, Søren;

    in between he polymer cushion and bulk water the layer was attributed to water of reduced density and was called "depletion layer".  Impurities or preparative artefacts were excluded as its origin. Later on, the formation of nanobubbles from this vapour-like water phase was initiated by tipping the......  The presence of a depletion layer of water along extended hydrophobic interfaces, and a possibly related formation of nanobubbles, is an ongoing discussion. The phenomenon was initially reported when we, years ago, chose thick films (~300-400Å) of polystyrene as cushions between a crystalline...... carrier and biomimetic membranes deposited thereupon and exposed to bulk water. While monitoring the sequential build-up of the sandwiched composite structure by continuous neutron reflectivity experiments the formation of an unexpected additional layer was detected (1). Located at the polystyrene surface...

  19. Ozone depletion by hydrofluorocarbons

    Science.gov (United States)

    Hurwitz, Margaret M.; Fleming, Eric L.; Newman, Paul A.; Li, Feng; Mlawer, Eli; Cady-Pereira, Karen; Bailey, Roshelle

    2015-10-01

    Atmospheric concentrations of hydrofluorocarbons (HFCs) are projected to increase considerably in the coming decades. Chemistry climate model simulations forced by current projections show that HFCs will impact the global atmosphere increasingly through 2050. As strong radiative forcers, HFCs increase tropospheric and stratospheric temperatures, thereby enhancing ozone-destroying catalytic cycles and modifying the atmospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Simulations with the NASA Goddard Space Flight Center 2-D model show that HFC-125 is the most important contributor to HFC-related atmospheric change in 2050; its effects are comparable to the combined impacts of HFC-23, HFC-32, HFC-134a, and HFC-143a. Incorporating the interactions between chemistry, radiation, and dynamics, ozone depletion potentials (ODPs) for HFCs range from 0.39 × 10-3 to 30.0 × 10-3, approximately 100 times larger than previous ODP estimates which were based solely on chemical effects.

  20. Capital expenditure and depletion

    International Nuclear Information System (INIS)

    In the future, the increase in oil demand will be covered for the most part by non conventional oils, but conventional sources will continue to represent a preponderant share of the world oil supply. Their depletion represents a complex challenge involving technological, economic and political factors. At the same time, there is reason for concern about the decrease in exploration budgets at the major oil companies. (author)

  1. THE CYSTIC FIBROSIS TRANSMEMBRANE CONDUCTANCE REGULATOR (CFTR) IS EXPRESSED IN MATURATION STAGE AMELOBLASTS, ODONTOBLASTS AND BONE CELLS

    OpenAIRE

    Bronckers, Antonius; Kalogeraki, Lida; Jorna, Huub J.N.; Wilke, Martina; Bervoets, Theodore J.; LYARUU, DONACIAN M.; Zandieh-Doulabi, Behrouz; DenBesten, Pamela; de Jonge, Hugo

    2009-01-01

    Patients with cystic fibrosis (CF) have mild defects in dental enamel. The gene mutated in these patients is CFTR, a Cl− channel involved in transepithelial salt- and water transport and bicarbonate secretion. We tested the hypothesis that Cftr channels are present and operating in the plasma membranes of mouse ameloblasts.

  2. Altered intestinal bile salt biotransformation in a cystic fibrosis (Cftr(-/-)) mouse model with hepato-biliary pathology

    NARCIS (Netherlands)

    Bodewes, Frank A. J. A.; van der Wulp, Mariette Y. M.; Beharry, Satti; Doktorova, Marcela; Havinga, Rick; Boverhof, Renze; Phillips, M. James; Durie, Peter R.; Verkade, Henkjan J.

    2015-01-01

    Background: Cftr(-/-tm1UC) mice develop progressive hepato-biliary pathology. We hypothesize that this liver pathology is related to alterations' in biliary bile hydrophobicity and bile salt metabolism in Cftr(-/-tm1Unc) mice. Methods: We determined bile production, biliary and fecal bile salt- and

  3. A Class of High-affinity Bicyclooctane G551D-CFTR Activators Identified by High Throughput Screening

    Institute of Scientific and Technical Information of China (English)

    HE Cheng-yan; ZHAO Lu; LIU Yan-li; XU Li-na; SHANG De-jing; YANG Hong

    2004-01-01

    The glycine-to-aspartic acid missense mutation at the codon 551(G551D) of the cystic fibrosis transmembrane conductance regulator(CFTR) is one of the five most frequent cystic fibrosis(CF) mutations associated with a severe CF phenotype. To explore the feasibility of pharmacological correction of disrupted activation of CFTR chloride channel caused by G551D mutation, we developed a halide-sensitive fluorescence miniassay for G551D-CFTR in Fisher rat thyroid(FRT) epithelial cells for the discovery of novel activators of G551D-CFTR. A class of bicyclooctane small molecule compounds that efficiently stimulate G551D-CFTR chloride channel activity was identified by high throughput screening via the FRT cell-based assay. This class of compounds selectively activates G551D-CFTR with a high affinity, whereas little effect of the compounds on wildtype CFTR can be seen. The discovery of a class of bicyclooctane G551D-CFTR activators will permit the analysis of structure-activity relationship of the compounds to identify ideal leads for in vivo therapeutic studies.

  4. The cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in maturation stage ameloblasts, odontoblasts and bone cells

    NARCIS (Netherlands)

    A. Bronckers; L. Kalogeraki; H.J.N. Jorna; M. Wilke; T.J. Bervoets; D.M. Lyaruu; B. Zandieh-Doulabi; P. Denbesten; H. de Jonge

    2010-01-01

    Patients with cystic fibrosis (CF) have mild defects in dental enamel. The gene mutated in these patients is CFTR, a Cl− channel involved in transepithelial salt and water transport and bicarbonate secretion. We tested the hypothesis that Cftr channels are present and operating in the plasma membran

  5. The primary folding defect and rescue of ΔF508 CFTR emerge during translation of the mutant domain

    NARCIS (Netherlands)

    Hoelen, H.M.; Kleizen, B.; Schmidt, A.; Richardson, J.; Charitou, P.; Braakman, L.J.; Thomas, P. J.

    2010-01-01

    In the vast majority of cystic fibrosis (CF) patients, deletion of residue F508 from CFTR is the cause of disease. F508 resides in the first nucleotide binding domain (NBD1) and its absence leads to CFTR misfolding and degradation. We show here that the primary folding defect arises during synthesis

  6. Self-reactive CFTR T cells in humans: implications for gene therapy.

    Science.gov (United States)

    Calcedo, Roberto; Griesenbach, Uta; Dorgan, Daniel J; Soussi, Samia; Boyd, A Christopher; Davies, Jane C; Higgins, Tracy E; Hyde, Stephen C; Gill, Deborah R; Innes, J Alastair; Porteous, David J; Alton, Eric W; Wilson, James M; Limberis, Maria P

    2013-09-01

    Cystic fibrosis (CF) is one of the most common autosomal recessive lethal disorders affecting white populations of northern European ancestry. To date there is no cure for CF. Life-long treatments for CF are being developed and include gene therapy and the use of small-molecule drugs designed to target specific cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations. Irrespective of the type of molecular therapy for CF, which may include gene replacement, exon skipping, nonsense suppression, or molecular correctors, because all of these modulate gene expression there is an inherent risk of activation of T cells against the wild-type version of CFTR. Here we report the validation of the human interferon-γ enzyme-linked immunospot assay and its application for the analysis of CFTR-specific T cell responses in patients with CF and in non-CF subjects. We found non-CF subjects with low levels of self-reactive CFTR-specific T cells in the United States and several patients with CF with low to high levels of self-reactive CFTR-specific T cells in both the United States and the United Kingdom. PMID:23790242

  7. Obligate coupling of CFTR pore opening to tight nucleotide-binding domain dimerization.

    Science.gov (United States)

    Mihályi, Csaba; Töröcsik, Beáta; Csanády, László

    2016-01-01

    In CFTR, the chloride channel mutated in cystic fibrosis (CF) patients, ATP-binding-induced dimerization of two cytosolic nucleotide binding domains (NBDs) opens the pore, and dimer disruption following ATP hydrolysis closes it. Spontaneous openings without ATP are rare in wild-type CFTR, but in certain CF mutants constitute the only gating mechanism, stimulated by ivacaftor, a clinically approved CFTR potentiator. The molecular motions underlying spontaneous gating are unclear. Here we correlate energetic coupling between residues across the dimer interface with spontaneous pore opening/closure in single CFTR channels. We show that spontaneous openings are also strictly coupled to NBD dimerization, which may therefore occur even without ATP. Coordinated NBD/pore movements are therefore intrinsic to CFTR: ATP alters the stability, but not the fundamental structural architecture, of open- and closed-pore conformations. This explains correlated effects of phosphorylation, mutations, and drugs on ATP-driven and spontaneous activity, providing insights for understanding CF mutation and drug mechanisms. PMID:27328319

  8. Activation of CFTR-mediated CI-Transport by Capsaicinoids in Cell Culture Model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xue-liang; HOU Ting-ting; GE Hong; SUN Juan-juan; YANG Hong; MA Tong-hui

    2009-01-01

    Previous studies reported that capsaicin potentiates ΔF508 mutant cystic fibrosis transmembrane conductance regulator(CFTR) channel gating defect by transfected cell-based assays.It has been postulated that orally ingested capsaicin may conceptually be used to develop a therapeutic strategy to treat gastrointestinal disorders in CF patients.We tried to reproduce and extend those pre-clinical data of previous studies.Cell-based fluorescence functional measurements in Fischer thyroid epithelial cells(FRT) expressing CFTR showed no effect of capsaicin on potentiating ΔF508-CFTR.while genistein showed a strongly positive activity.Studies show that capsaicin and dihydrocapsaicin activated cAMP-prestimulated wild-type CFTR in a dose-dependent manner with a maximal response of 70% of that activated by genistein,thus gave an apparent EC50 of (40.4±6.8)μmol/L and (150.2±7.4) μmol/L respectively.Preliminary study shows that the binding sites for capsaicin and dihydrocapsaicin may be probably partially overlapped with that for genistein because the maximal activation of wild-type CFTR with genistein is partially blocked by capsaicin and dihydrocapsaicin.

  9. Testing fully depleted CCD

    Science.gov (United States)

    Casas, Ricard; Cardiel-Sas, Laia; Castander, Francisco J.; Jiménez, Jorge; de Vicente, Juan

    2014-08-01

    The focal plane of the PAU camera is composed of eighteen 2K x 4K CCDs. These devices, plus four spares, were provided by the Japanese company Hamamatsu Photonics K.K. with type no. S10892-04(X). These detectors are 200 μm thick fully depleted and back illuminated with an n-type silicon base. They have been built with a specific coating to be sensitive in the range from 300 to 1,100 nm. Their square pixel size is 15 μm. The read-out system consists of a Monsoon controller (NOAO) and the panVIEW software package. The deafualt CCD read-out speed is 133 kpixel/s. This is the value used in the calibration process. Before installing these devices in the camera focal plane, they were characterized using the facilities of the ICE (CSIC- IEEC) and IFAE in the UAB Campus in Bellaterra (Barcelona, Catalonia, Spain). The basic tests performed for all CCDs were to obtain the photon transfer curve (PTC), the charge transfer efficiency (CTE) using X-rays and the EPER method, linearity, read-out noise, dark current, persistence, cosmetics and quantum efficiency. The X-rays images were also used for the analysis of the charge diffusion for different substrate voltages (VSUB). Regarding the cosmetics, and in addition to white and dark pixels, some patterns were also found. The first one, which appears in all devices, is the presence of half circles in the external edges. The origin of this pattern can be related to the assembly process. A second one appears in the dark images, and shows bright arcs connecting corners along the vertical axis of the CCD. This feature appears in all CCDs exactly in the same position so our guess is that the pattern is due to electrical fields. Finally, and just in two devices, there is a spot with wavelength dependence whose origin could be the result of a defectous coating process.

  10. Ecological considerations of natural and depleted uranium

    International Nuclear Information System (INIS)

    Depleted 238U is a major by-product of the nuclear fuel cycle for which increasing use is being made in counterweights, radiation shielding, and ordnance applications. This paper (1) summarizes the pertinent literature on natural and depleted uranium in the environment, (2) integrates results of a series of ecological studies conducted at Los Alamos Scientific Laboratory (LASL) in New Mexico where 70,000 kg of depleted and natural uranium has been expended to the environment over the past 34 years, and (3) synthesizes the information into an assessment of the ecological consequences of natural and depleted uranium released to the environment by various means. Results of studies of soil, plant, and animal communities exposed to this radiation and chemical environment over a third of a century provide a means of evaluating the behavior and effects of uranium in many contexts

  11. Ozone-depleting Substances (ODS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This site includes all of the ozone-depleting substances (ODS) recognized by the Montreal Protocol. The data include ozone depletion potentials (ODP), global...

  12. CFTR抑制ApoE-/-鼠高同型半胱氨酸血症诱导的肝损伤%CFTR suppressing hyperhomocysteinemia-induced hepatocyte damage in ApoE-/-mice

    Institute of Scientific and Technical Information of China (English)

    焦运; 杨安宁; 孙岳; 孔繁琪; 杨晓玲; 张鸣号; 金少举; 姜怡邓

    2016-01-01

    目的:探讨囊性纤维化跨膜转导调节因子(CFTR)在高同型半胱氨酸血症(HHcy)致 ApoE-/-鼠肝损伤中的作用。方法:5周龄雄性 ApoE-/-鼠36只随机分为模型对照组、模型组和治疗组,分别给予普通、高蛋氨酸、高蛋氨酸加叶酸饮食,C57BL/6J 雄鼠12只,普通饮食,为正常对照组。检测小鼠血清 Hcy、ALT和AST 变化,Hcy(100μmol/L)及100 Hcy + F (100μmol/L Hcy +叶酸)干预肝细胞后,检测肝组织和细胞内 CFTR mRNA 和蛋白水平,分析 CFTR 激动剂(VX-770)与抑制剂[CFTR(inh)-17]干预细胞后对CFTR 表达及 ALT 和 AST 含量的影响。结果:模型组 ApoE-/-鼠血清 Hcy、ALT 和 AST 显著升高, CFTR表达下降(P <0.05),而治疗组可拮抗 Hcy、ALT、AST、CFTR 的改变(P <0.05);Hcy (100μmol/L)引起肝细胞 CFTR 表达降低而 ALT 和 AST 升高(P <0.05),叶酸对这一改变起缓解作用。 VX-770和 CFTR (inh)-17干预后可改变肝细胞内ALT 和AST 含量。结论: CFTR 通过调控 ALT 和 AST 抑制 HHcy 致肝细胞损伤过程。%Objective To investigate the function of CFTR in ApoE-/- mice with HHcy-induced hepato-cellular injury. Methods Thirty six 5-week old ApoE-/- mice were divided into three groups , including the ApoE-/- group, the HHcy group and the intervention group, (n = 12). Twelve normal C57BL/6J mice were fed with regular mouse diet as the normal control (SPF grade). HL-7702 human liver cells were intervened by Hcy (100 μmol/L) and 100 μmol/L Hcy + folic acid (100 μmol/L Hcy + F). The changes of Hcy, ALT and AST in the serum and the expression of CFTR mRNA and protein in liver and liver cells were detected. The concen-trations of ALT and AST in the liver cell intervened by VX-770 agonist and CFTR(inh)-172 inhibitor were mea-sured by ELISA. Results Compared with the control group , the levels of Hcy , ALT and AST were higher

  13. Issues in Stratospheric Ozone Depletion.

    Science.gov (United States)

    Lloyd, Steven Andrew

    measurements. Therefore a laboratory prototype of an instrument to measure ClONO _2 concentrations in situ was developed, adapting techniques recently developed in this research group to measure ClO concentrations at the part-per-trillion level. The detection scheme involves heating a flowing air sample to almost 500K, thermally dissociating ClONO _2 into ClO and NO_2 , and measuring the resulting ClO concentration by titrating with NO to produce Cl atoms, which are detected by resonance fluoresence. The calibration of this technique is very sensitive to flow parameters (temperature, pressure, flow velocity, added NO concentration, and homogeneity of flow). The issues developed in this thesis contribute to our understanding of the mechanisms of stratospheric ozone depletion and its potential global impact. It is becoming increasingly apparent that our ability to predict the future course of global ozone depletion is critically dependent on our ability to reproduce in situ and remote measurements with numerical models.

  14. Conformationally rigid histone deacetylase inhibitors correct DF508-CFTR protein function

    DEFF Research Database (Denmark)

    Vickers, Chris J.; Olsen, Christian Adam; Hutt, Darren M.;

    2011-01-01

    Histone deacetylase (HDAC) inhibitors have shown partial efficacy toward correcting cystic fibrosis transmembrane conductance regulator (CFTR) protein function in ΔF508- CFTR models. While current treatment options for CF generally concentrate on disease symptoms such as management of inflammation...... and bacterial infection, therapy using HDAC inhibitors has the potential to treat and correct the underlying etiology associated with the disorder. Subsequently, we have synthesized conformationally well-defined cyclic tetrapeptide derivatives based on the natural product HDAC inhibitor Apicidin, in order...... to formulate a pharmacophore model to describe and enhance the bioactivity of these molecules. Through this study we have developed HDAC inhibitors which improve CFTR trafficking from the endoplasmic reticulum (ER) while ultimately increasing ion conductance across the plasma membrane of a lung epithelial cell...

  15. Resveratrol increases F508del-CFTR dependent salivary secretion in cystic fibrosis mice

    Directory of Open Access Journals (Sweden)

    Barbara Dhooghe

    2015-07-01

    Full Text Available Cystic fibrosis (CF is a fatal genetic disease associated with widespread exocrine gland dysfunction. Studies have suggested activating effects of resveratrol, a naturally-occurring polyphenol compound with antioxidant and anti-inflammatory properties, on CF transmembrane conductance regulator (CFTR protein function. We assayed, in F508del-CFTR homozygous (CF and in wild-type mice, the effect of resveratrol on salivary secretion in basal conditions, in response to inhibition by atropine (basal β-adrenergic-dependent component and to stimulation by isoprenaline (CFTR-dependent component. Both components of the salivary secretion were smaller in CF mice than in controls. Two hours after intraperitoneal administration of resveratrol (50 mg/kg dissolved in DMSO, the compound was detected in salivary glands. As in both CF and in wild-type mice, DMSO alone increased the response to isoprenaline in males but not in females, the effect of resveratrol was only measured in females. In wild-type mice, isoprenaline increased secretion by more than half. In CF mice, resveratrol rescued the response to isoprenaline, eliciting a 2.5-fold increase of β-adrenergic-stimulated secretion. We conclude that the salivary secretion assay is suitable to test DMSO-soluble CFTR modulators in female mice. We show that resveratrol applied in vivo to mice reaches salivary glands and increases β-adrenergic secretion. Immunolabelling of CFTR in human bronchial epithelial cells suggests that the effect is associated with increased CFTR protein expression. Our data support the view that resveratrol is beneficial for treating CF. The salivary secretion assay has a potential application to test efficacy of novel CF therapies.

  16. Stratospheric ozone depletion

    International Nuclear Information System (INIS)

    The amount of stratospheric ozone and the reduction of the ozone layer vary according to seasons and latitudes. At present total and vertical ozone is monitored over all Austria. The mean monthly ozone levels between 1994 and 2000 are presented. Data on stratospheric ozone and UV-B radiation are published daily on the home page http: www.lebesministerium.at. The use of ozone depleting substances such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) is provided. Besides, the national measures taken to reduce their use. Figs. 2, Tables 2. (nevyjel)

  17. Structure and Dynamics of NBD1 from CFTR Characterized Using Crystallography and Hydrogen/Deuterium Exchange Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, H.A.; Wang, C.; Zhao, X.; Hamuro, Y.; Conners, K.; Kearins, M.C.; Lu, F.; Sauder, J.M.; Molnar, K.S.; Coales, S.J.; Maloney, P.C.; Guggino, W.B.; Wetmore, D.R.; Weber, P.C.; Hunt, J.F. (SGX); (ExSAR); (Cystic); (JHU-MED); (Columbia)

    2012-04-30

    The {Delta}F508 mutation in nucleotide-binding domain 1 (NBD1) of the cystic fibrosis transmembrane conductance regulator (CFTR) is the predominant cause of cystic fibrosis. Previous biophysical studies on human F508 and {Delta}F508 domains showed only local structural changes restricted to residues 509-511 and only minor differences in folding rate and stability. These results were remarkable because {Delta}F508 was widely assumed to perturb domain folding based on the fact that it prevents trafficking of CFTR out of the endoplasmic reticulum. However, the previously reported crystal structures did not come from matched F508 and {Delta}F508 constructs, and the {Delta}F508 structure contained additional mutations that were required to obtain sufficient protein solubility. In this article, we present additional biophysical studies of NBD1 designed to address these ambiguities. Mass spectral measurements of backbone amide {sup 1}H/{sup 2}H exchange rates in matched F508 and {Delta}F508 constructs reveal that {Delta}F508 increases backbone dynamics at residues 509-511 and the adjacent protein segments but not elsewhere in NBD1. These measurements also confirm a high level of flexibility in the protein segments exhibiting variable conformations in the crystal structures. We additionally present crystal structures of a broader set of human NBD1 constructs, including one harboring the native F508 residue and others harboring the {Delta}F508 mutation in the presence of fewer and different solubilizing mutations. The only consistent conformational difference is observed at residues 509-511. The side chain of residue V510 in this loop is mostly buried in all non-{Delta}F508 structures but completely solvent exposed in all {Delta}F508 structures. These results reinforce the importance of the perturbation {Delta}F508 causes in the surface topography of NBD1 in a region likely to mediate contact with the transmembrane domains of CFTR. However, they also suggest that increased

  18. The modality effect of ego depletion: Auditory task modality reduces ego depletion.

    Science.gov (United States)

    Li, Qiong; Wang, Zhenhong

    2016-08-01

    An initial act of self-control that impairs subsequent acts of self-control is called ego depletion. The ego depletion phenomenon has been observed consistently. The modality effect refers to the effect of the presentation modality on the processing of stimuli. The modality effect was also robustly found in a large body of research. However, no study to date has examined the modality effects of ego depletion. This issue was addressed in the current study. In Experiment 1, after all participants completed a handgrip task, one group's participants completed a visual attention regulation task and the other group's participants completed an auditory attention regulation task, and then all participants again completed a handgrip task. The ego depletion phenomenon was observed in both the visual and the auditory attention regulation task. Moreover, participants who completed the visual task performed worse on the handgrip task than participants who completed the auditory task, which indicated that there was high ego depletion in the visual task condition. In Experiment 2, participants completed an initial task that either did or did not deplete self-control resources, and then they completed a second visual or auditory attention control task. The results indicated that depleted participants performed better on the auditory attention control task than the visual attention control task. These findings suggest that altering task modality may reduce ego depletion. PMID:27241617

  19. Functional interaction between CFTR and the sodium-phosphate co-transport type 2a in Xenopus laevis oocytes.

    Directory of Open Access Journals (Sweden)

    Naziha Bakouh

    Full Text Available BACKGROUND: A growing number of proteins, including ion transporters, have been shown to interact with Cystic Fibrosis Transmembrane conductance Regulator (CFTR. CFTR is an epithelial chloride channel that is involved in Cystic Fibrosis (CF when mutated; thus a better knowledge of its functional interactome may help to understand the pathophysiology of this complex disease. In the present study, we investigated if CFTR and the sodium-phosphate co-transporter type 2a (NPT2a functionally interact after heterologous expression of both proteins in Xenopus laevis oocytes. METHODOLOGY/FINDINGS: NPT2a was expressed alone or in combination with CFTR in X. laevis oocytes. Using the two-electrode voltage-clamp technique, the inorganic phosphate-induced current (IPi was measured and taken as an index of NPT2a activity. The maximal IPi for NPT2a substrates was reduced when CFTR was co-expressed with NPT2a, suggesting a decrease in its expression at the oolemna. This was consistent with Western blot analysis showing reduced NPT2a plasma membrane expression in oocytes co-expressing both proteins, whereas NPT2a protein level in total cell lysate was the same in NPT2a- and NPT2a+CFTR-oocytes. In NPT2a+CFTR- but not in NPT2a-oocytes, IPi and NPT2a surface expression were increased upon PKA stimulation, whereas stimulation of Exchange Protein directly Activated by cAMP (EPAC had no effect. When NPT2a-oocytes were injected with NEG2, a short amino-acid sequence from the CFTR regulatory domain that regulates PKA-dependent CFTR trafficking to the plasma membrane, IPi values and NPT2a membrane expression were diminished, and could be enhanced by PKA stimulation, thereby mimicking the effects of CFTR co-expression. CONCLUSION/PERSPECTIVES: We conclude that when both CFTR and NPT2a are expressed in X. laevis oocytes, CFTR confers to NPT2a a cAMPi-dependent trafficking to the membrane. This functional interaction raises the hypothesis that CFTR may play a role in

  20. The human CFTR protein expressed in CHO cells activates aquaporin-3 in a cAMP-dependent pathway: study by digital holographic microscopy

    KAUST Repository

    Jourdain, P.

    2013-12-11

    The transmembrane water movements during cellular processes and their relationship to ionic channel activity remain largely unknown. As an example, in epithelial cells it was proposed that the movement of water could be directly linked to cystic fibrosis transmembrane conductance regulator (CFTR) protein activity through a cAMP-stimulated aqueous pore, or be dependent on aquaporin. Here, we used digital holographic microscopy (DHM) an interferometric technique to quantify in situ the transmembrane water fluxes during the activity of the epithelial chloride channel, CFTR, measured by patch-clamp and iodide efflux techniques. We showed that the water transport measured by DHM is fully inhibited by the selective CFTR blocker CFTRinh172 and is absent in cells lacking CFTR. Of note, in cells expressing the mutated version of CFTR (F508del-CFTR), which mimics the most common genetic alteration encountered in cystic fibrosis, we also show that the water movement is profoundly altered but restored by pharmacological manipulation of F508del-CFTR-defective trafficking. Importantly, whereas activation of this endogenous water channel required a cAMP-dependent stimulation of CFTR, activation of CFTR or F508del-CFTR by two cAMP-independent CFTR activators, genistein and MPB91, failed to trigger water movements. Finally, using a specific small-interfering RNA against the endogenous aquaporin AQP3, the water transport accompanying CFTR activity decreased. We conclude that water fluxes accompanying CFTR activity are linked to AQP3 but not to a cAMP-stimulated aqueous pore in the CFTR protein.

  1. Pseudomonas aeruginosa Reduces VX-809 Stimulated F508del-CFTR Chloride Secretion by Airway Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Bruce A Stanton

    Full Text Available P. aeruginosa is an opportunistic pathogen that chronically infects the lungs of 85% of adult patients with Cystic Fibrosis (CF. Previously, we demonstrated that P. aeruginosa reduced wt-CFTR Cl secretion by airway epithelial cells. Recently, a new investigational drug VX-809 has been shown to increase F508del-CFTR Cl secretion in human bronchial epithelial (HBE cells, and, in combination with VX-770, to increase FEV1 (forced expiratory volume in 1 second by an average of 3-5% in CF patients homozygous for the F508del-CFTR mutation. We propose that P. aeruginosa infection of CF lungs reduces VX-809 + VX-770- stimulated F508del-CFTR Cl secretion, and thereby reduces the clinical efficacy of VX-809 + VX-770.F508del-CFBE cells and primary cultures of CF-HBE cells (F508del/F508del were exposed to VX-809 alone or a combination of VX-809 + VX-770 for 48 hours and the effect of P. aeruginosa on F508del-CFTR Cl secretion was measured in Ussing chambers. The effect of VX-809 on F508del-CFTR abundance was measured by cell surface biotinylation and western blot analysis. PAO1, PA14, PAK and 6 clinical isolates of P. aeruginosa (3 mucoid and 3 non-mucoid significantly reduced drug stimulated F508del-CFTR Cl secretion, and plasma membrane F508del-CFTR.The observation that P. aeruginosa reduces VX-809 and VX-809 + VX-770 stimulated F508del CFTR Cl secretion may explain, in part, why VX-809 + VX-770 has modest efficacy in clinical trials.

  2. Applicability and Efficiency of NGS in Routine Diagnosis: In-Depth Performance Analysis of a Complete Workflow for CFTR Mutation Analysis.

    Directory of Open Access Journals (Sweden)

    Adrien Pagin

    Full Text Available Actually, about 2000 sequence variations have been documented in the CFTR gene requiring extensive and multi-step genetic testing in the diagnosis of cystic fibrosis and CFTR-related disorders. We present a two phases study, with validation and performance monitoring, of a single experiment methodology based on multiplex PCR and high throughput sequencing that allows detection of all variants, including large rearrangements, affecting the coding regions plus three deep intronic loci.A total of 340 samples, including 257 patients and 83 previously characterized control samples, were sequenced in 17 MiSeq runs and analyzed with two bioinformatic pipelines in routine diagnostic conditions. We obtained 100% coverage for all the target regions in every tested sample.We correctly identified all the 87 known variants in the control samples and successfully confirmed the 62 variants identified among the patients without observing false positive results. Large rearrangements were identified in 18/18 control samples. Only 17 patient samples showed false positive signals (6.6%, 12 of which showed a borderline result for a single amplicon. We also demonstrated the ability of the assay to detect allele specific dropout of amplicons when a sequence variation occurs at a primer binding site thus limiting the risk for false negative results.We described here the first NGS workflow for CFTR routine analysis that demonstrated equivalent diagnostic performances compared to Sanger sequencing and multiplex ligation-dependent probe amplification. This study illustrates the advantages of NGS in term of scalability, workload reduction and cost-effectiveness in combination with an improvement of the overall data quality due to the simultaneous detection of SNVs and large rearrangements.

  3. Funciones de los canales iónicos CFTR y ENAC en la fibrosis quística

    OpenAIRE

    Alejandra G. Palma; Basilio A. Kotsias; Gabriela I. Marino

    2014-01-01

    La fibrosis quística se debe a la ausencia o defecto del canal transmembrana regulador de la fibrosis quística (CFTR), un canal de cloruro codificado en el gen cftr que juega un papel clave en la homeostasis del agua e iones. El CFTR es activado por el AMPc y se localiza en las membranas apicales y basolaterales de las vías aéreas, intestino y glándulas exocrinas. Una de sus funciones primarias en los pulmones es mantener la capa de líquido superficial a través de su función de canal y regula...

  4. CFTR delivery to 25% of surface epithelial cells restores normal rates of mucus transport to human cystic fibrosis airway epithelium.

    Directory of Open Access Journals (Sweden)

    Liqun Zhang

    2009-07-01

    Full Text Available Dysfunction of CFTR in cystic fibrosis (CF airway epithelium perturbs the normal regulation of ion transport, leading to a reduced volume of airway surface liquid (ASL, mucus dehydration, decreased mucus transport, and mucus plugging of the airways. CFTR is normally expressed in ciliated epithelial cells of the surface and submucosal gland ductal epithelium and submucosal gland acinar cells. Critical questions for the development of gene transfer strategies for CF airway disease are what airway regions require CFTR function and how many epithelial cells require CFTR expression to restore normal ASL volume regulation and mucus transport to CF airway epithelium? An in vitro model of human CF ciliated surface airway epithelium (CF HAE was used to test whether a human parainfluenza virus (PIV vector engineered to express CFTR (PIVCFTR could deliver sufficient CFTR to CF HAE to restore mucus transport, thus correcting the CF phenotype. PIVCFTR delivered CFTR to >60% of airway surface epithelial cells and expressed CFTR protein in CF HAE approximately 100-fold over endogenous levels in non-CF HAE. This efficiency of CFTR delivery fully corrected the basic bioelectric defects of Cl(- and Na(+ epithelial ion transport and restored ASL volume regulation and mucus transport to levels approaching those of non-CF HAE. To determine the numbers of CF HAE surface epithelial cells required to express CFTR for restoration of mucus transport to normal levels, different amounts of PIVCFTR were used to express CFTR in 3%-65% of the surface epithelial cells of CF HAE and correlated to increasing ASL volumes and mucus transport rates. These data demonstrate for the first time, to our knowledge, that restoration of normal mucus transport rates in CF HAE was achieved after CFTR delivery to 25% of surface epithelial cells. In vivo experimentation in appropriate models will be required to determine what level of mucus transport will afford clinical benefit to CF patients

  5. Comprehensive and accurate mutation scanning of the CFTR gene by two-dimensional DNA electrophoresis

    NARCIS (Netherlands)

    Wu, Y; Hofstra, RMW; Scheffer, H; Uitterlinden, AG; Mullaart, E; Buys, CHCM; Vijg, J

    1996-01-01

    The large number of possible disease causing mutations in the 27 exons of the cystic fibrosis transmembrane conductance regulator (CFTR) gene has severely limited direct diagnosis of cystic fibrosis (CF) patients and carriers by mutation detection. Here we show that in principle testing for mutation

  6. Cholic acid induces a Cftr dependent biliary secretion and liver growth response in mice

    NARCIS (Netherlands)

    Bodewes, Frank A. J. A.; Bijvelds, Marcel J.; de Vries, Willemien; Baller, Juul F. W.; Gouw, Annette S. H.; de Jonge, Hugo R.; Verkade, Henkjan J.

    2015-01-01

    The cause of Cystic fibrosis liver disease (CFLD), is unknown. It is well recognized that hepatic exposure to hydrophobic bile salts is associated with the development of liver disease. For this reason, we hypothesize that, CFTR dependent variations, in the hepatic handling of hydrophobic bile salts

  7. Critical Role of Cystic Fibrosis Transmembrane Conductance Regulation(CFTR)in Female Reproduction

    Institute of Scientific and Technical Information of China (English)

    Hsiao Chang CHAN

    2003-01-01

    @@ Cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-activated Cl- channel, mutations of which are responsible for defective Cl- and/or HCO-3 secretions seen in cystic fibrosis (CF), a common lethal genetic disease affecting most exocrine glands/organs, including the lungs, intestine, pancreas and reproductive tracts of both sexes.

  8. Cholic acid induces a Cftr dependent biliary secretion and liver growth response in mice

    NARCIS (Netherlands)

    F.A.J.A. Bodewes (Frank); M.J.C. Bijvelds (Marcel); De Vries, W. (Willemien); Baller, J.F.W. (Juul F. W.); A.S.H. Gouw (Annette); H.R. de Jonge (Hugo); H.J. Verkade (Henkjan)

    2015-01-01

    textabstractThe cause of Cystic fibrosis liver disease (CFLD), is unknown. It is well recognized that hepatic exposure to hydrophobic bile salts is associated with the development of liver disease. For this reason, we hypothesize that, CFTR dependent variations, in the hepatic handling of hydrophobi

  9. Frequency of CFTR, SPINK1, and Cathepsin B Gene Mutation in North Indian Population: Connections between Genetics and Clinical Data

    Directory of Open Access Journals (Sweden)

    Shweta Singh

    2014-01-01

    Full Text Available Objectives. Genetic mutations and polymorphisms have been correlated with chronic pancreatitis (CP. This study aims to investigate the association of genetic variants of cystic fibrosis transmembrane conductance regulator (CFTR and serine protease inhibitor Kazal type 1 (SPINK-1 genes and Cathepsin B gene polymorphisms with CP and to associate genetic backgrounds with clinical phenotypes. Methods. 150 CP patients and 150 normal controls were enrolled consecutively. We analyzed SPINK-1 N34S and IVS3+2T>C gene mutations by PCR-restriction-fragment length polymorphism (RFLP. The identification of DF508, G551D, G542X, R117H, and W1282X mutations was carried out by ARMS-PCR. S549N mutation, IVS8 polyTn polymorphism, and Cathepsin B Lec26Val were analysed by PCR-RFLP, nested PCR, and PCR-RFLP plus sequencing, respectively. Results. We found a significant association of SPINK1 (N34S gene polymorphism. IVS1−37T>C polymorphism shows linkage with 101A>G. 300 chromosomes belonging to the CFTR subgroup exhibited minor allele frequency of 0.04, 0.03, 0.03, 0.013, 0.006, and 0.02 for DF508, G452X, G551D, S549N, R117H, and IVS8 T5, respectively. Except for R117H and IVS8 T5 polymorphisms, all other mutations showed significant variation. Conclusion. Analysis of potential susceptibility variants is needed to support nature of the genes and environment in pancreatitis. This data may help establish genetic screening and prenatal setup for Indian population.

  10. Mutant cycles at CFTR's non-canonical ATP-binding site support little interface separation during gating.

    Science.gov (United States)

    Szollosi, Andras; Muallem, Daniella R; Csanády, László; Vergani, Paola

    2011-06-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride channel belonging to the adenosine triphosphate (ATP)-binding cassette (ABC) superfamily. ABC proteins share a common molecular mechanism that couples ATP binding and hydrolysis at two nucleotide-binding domains (NBDs) to diverse functions. This involves formation of NBD dimers, with ATP bound at two composite interfacial sites. In CFTR, intramolecular NBD dimerization is coupled to channel opening. Channel closing is triggered by hydrolysis of the ATP molecule bound at composite site 2. Site 1, which is non-canonical, binds nucleotide tightly but is not hydrolytic. Recently, based on kinetic arguments, it was suggested that this site remains closed for several gating cycles. To investigate movements at site 1 by an independent technique, we studied changes in thermodynamic coupling between pairs of residues on opposite sides of this site. The chosen targets are likely to interact based on both phylogenetic analysis and closeness on structural models. First, we mutated T460 in NBD1 and L1353 in NBD2 (the corresponding site-2 residues become energetically coupled as channels open). Mutation T460S accelerated closure in hydrolytic conditions and in the nonhydrolytic K1250R background; mutation L1353M did not affect these rates. Analysis of the double mutant showed additive effects of mutations, suggesting that energetic coupling between the two residues remains unchanged during the gating cycle. We next investigated pairs 460-1348 and 460-1375. Although both mutations H1348A and H1375A produced dramatic changes in hydrolytic and nonhydrolytic channel closing rates, in the corresponding double mutants these changes proved mostly additive with those caused by mutation T460S, suggesting little change in energetic coupling between either positions 460-1348 or positions 460-1375 during gating. These results provide independent support for a gating model in which ATP-bound composite site 1 remains

  11. The Toxicity of Depleted Uranium

    OpenAIRE

    Wayne Briner

    2010-01-01

    Depleted uranium (DU) is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a c...

  12. Depleted zinc: Properties, application, production

    International Nuclear Information System (INIS)

    The addition of ZnO, depleted in the Zn-64 isotope, to the water of boiling water nuclear reactors lessens the accumulation of Co-60 on the reactor interior surfaces, reduces radioactive wastes and increases the reactor service-life because of the inhibitory action of zinc on inter-granular stress corrosion cracking. To the same effect depleted zinc in the form of acetate dihydrate is used in pressurized water reactors. Gas centrifuge isotope separation method is applied for production of depleted zinc on the industrial scale. More than 20 years of depleted zinc application history demonstrates its benefits for reduction of NPP personnel radiation exposure and combating construction materials corrosion.

  13. EPRI depletion benchmark calculations using PARAGON

    International Nuclear Information System (INIS)

    Highlights: • PARAGON depletion calculations are benchmarked against the EPRI reactivity decrement experiments. • Benchmarks cover a wide range of enrichments, burnups, cooling times, and burnable absorbers, and different depletion and storage conditions. • Results from PARAGON-SCALE scheme are more conservative relative to the benchmark data. • ENDF/B-VII based data reduces the excess conservatism and brings the predictions closer to benchmark reactivity decrement values. - Abstract: In order to conservatively apply burnup credit in spent fuel pool criticality analyses, code validation for both fresh and used fuel is required. Fresh fuel validation is typically done by modeling experiments from the “International Handbook.” A depletion validation can determine a bias and bias uncertainty for the worth of the isotopes not found in the fresh fuel critical experiments. Westinghouse’s burnup credit methodology uses PARAGON™ (Westinghouse 2-D lattice physics code) and its 70-group cross-section library, which have been benchmarked, qualified, and licensed both as a standalone transport code and as a nuclear data source for core design simulations. A bias and bias uncertainty for the worth of depletion isotopes, however, are not available for PARAGON. Instead, the 5% decrement approach for depletion uncertainty is used, as set forth in the Kopp memo. Recently, EPRI developed a set of benchmarks based on a large set of power distribution measurements to ascertain reactivity biases. The depletion reactivity has been used to create 11 benchmark cases for 10, 20, 30, 40, 50, and 60 GWd/MTU and 3 cooling times 100 h, 5 years, and 15 years. These benchmark cases are analyzed with PARAGON and the SCALE package and sensitivity studies are performed using different cross-section libraries based on ENDF/B-VI.3 and ENDF/B-VII data to assess that the 5% decrement approach is conservative for determining depletion uncertainty

  14. CFTR gene transfer to lung epithelium--on the trail of a target cell.

    Science.gov (United States)

    O'Dea, S; Harrison, D J

    2002-05-01

    Cystic fibrosis (CF) is a lethal inherited disease that afflicts up to 1 in 2,500 people in the western world. Since 1989, when mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene were identified as responsible for the disease, intense effort has been applied to the development of replacement gene therapy strategies to cure CF. Problems with basic gene delivery techniques along with limited knowledge of the pathogenesis of CF have hindered progress so far. However, recent insights into the expression patterns and functions of CFTR in developing and adult lungs are now advancing our understanding of this disease. It is becoming apparent that progress in gene delivery to cure CF may be best served by identification of a target cell(s) around which gene transfer strategies can be specifically tailored to most closely reproduce the effects of normal CFTR expression. In fact, accurate restoration of endogenous expression patterns may be crucial, not only for disease reversal, but also to avoid potentially deleterious effects of inappropriate expression. This approach is in turn confounded however, by ill-defined stem and progenitor cell pathways within the lung epithelium. Nonetheless, studies to date suggest that these pathways are relatively plastic and may respond differently during homeostasis compared with repair following injury. It may therefore be feasible to target the lung epithelium in a non-cell specific manner and allow endogenous differentiation pathways to subsequently establish correct CFTR distribution patterns. In this review, emerging information on CFTR expression and function in developing and adult lungs is discussed in the context of putative stem cell populations and their potential for current gene delivery approaches. PMID:12109214

  15. Stimulation of airway and intestinal mucosal secretion by natural coumarin CFTR activators

    Directory of Open Access Journals (Sweden)

    Hong eYang

    2011-09-01

    Full Text Available Mutations of cystic fibrosis transmembrane conductance regulator (CFTR cause lethal hereditary disease cystic fibrosis (CF that involves extensive destruction and dysfunction of serous epithelium. Possible pharmacological therapy includes correction of defective intracellular processing and abnormal channel gating. In a previous study, we identified five natural coumarin potentiators of Δ508-CFTR including osthole, imperatorin, isopsoralen, praeruptorin A and scoparone. The present study was designed to determine the activity of these coumarine compounds on CFTR activity in animal tissues as a primary evaluation of their therapeutic potential. In the present study, we analyzed the affinity of these coumarin potentiators in activating wild-type CFTR and found that they are all potent activators. Osthole showed the highest affinity with Kd values <50 nmol/L as determined by Ussing chamber short-circuit current assay. Stimulation of rat colonic mucosal secretion by osthole was tested by the Ussing chamber short-circuit current assay. Osthole reached maximal activation of colonic Cl- secretion at 5 mol/L. Stimulation of mouse tracheal mucosal secretion was analyzed by optical measurement of single gland secretion. Fluid secretion rate of tracheal single submucosal gland stimulated by osthole at 10mol/L was 3-fold more rapid than that in negative control. In both cases the stimulated secretions were fully abolished by CFTRinh-172. In conclusion, the effective stimulation of Cl– and fluid secretion in colonic and tracheal mucosa by osthole suggested the therapeutic potential of natural coumarine compounds for the treatment of cystic fibrosis and other CFTR-related diseases.

  16. Comprehensive screening for PRSS1, SPINK1, CFTR, CTRC and CLDN2 gene mutations in Chinese paediatric patients with idiopathic chronic pancreatitis: a cohort study

    Science.gov (United States)

    Wang, Wei; Sun, Xiao-Tian; Weng, Xiao-Ling; Zhou, Dai-Zhan; Sun, Chang; Xia, Tian; Hu, Liang-Hao; Lai, Xiao-Wei; Ye, Bo; Liu, Mu-Yun; Jiang, Fei; Gao, Jun; Bo, Lu-Min; Liu, Yun; Liao, Zhuan; Li, Zhao-Shen

    2013-01-01

    Objective Genetic alterations may contribute to chronic pancreatitis (CP) in Chinese young patients. This study was designed to investigate mutations of cationic trypsinogen (PRSS1), pancreatic secretory trypsin inhibitor or serine protease inhibitor Kazal type 1 (SPINK1), cystic fibrosis transmembrane conductance regulator (CFTR), chymotrypsin C (CTRC) and CLDN2 genes and the copy number variations (CNVs) of PRSS1 and asses associations with the development of idiopathic CP (ICP) in Chinese children. Design Retrospective. Setting A single center. Participants 75 ICP Chinese children (40 boys and 35 girls). Primary and secondary outcome measures Mutations of PRSS1, SPINK1, CFTR, CTRC and CLDN2 genes and CNVs. Results 7 patients had heterozygous mutations in PRSS1, that is, N29I (n=1), R122H or R122C (n=6). The CNVs of PRSS1 in five patients had abnormal copies (1 copy (n=4), five copies (n=1)). 43 patients had IVS3+2T>C (rs148954387) (10 homozygous and 33 heterozygous) in SPINK1. None of the PRSS1 mutation patients carried a SPINK1 mutation. Frequency of PRSS1 and SPINK1 mutations was 9.3% and 57.3%, respectively, with an overall frequency of 66.6% (50/75). In addition, one patient had a novel deletion of CFTR (GCTTCCTA from c.500 to c.508 leading to the shortened polypeptide molecule via a stop codon). Another patient had a novel missense in CLDN2 exon 2 (c.592A>C mutation). Clinically, patients with SPINK1 mutations had a higher rate of pancreatic duct stones, pancreatic pseudocyst and pancreatic calcification than those without SPINK1 mutations (pC mutation may play an important role in the pathogenesis of Chinese paediatric ICP. However, further study is needed to confirm and to investigate the role of these genes in the development of Chinese ICP. PMID:24002981

  17. Depletion sensitivity predicts unhealthy snack purchases.

    Science.gov (United States)

    Salmon, Stefanie J; Adriaanse, Marieke A; Fennis, Bob M; De Vet, Emely; De Ridder, Denise T D

    2016-01-01

    The aim of the present research is to examine the relation between depletion sensitivity - a novel construct referring to the speed or ease by which one's self-control resources are drained - and snack purchase behavior. In addition, interactions between depletion sensitivity and the goal to lose weight on snack purchase behavior were explored. Participants included in the study were instructed to report every snack they bought over the course of one week. The dependent variables were the number of healthy and unhealthy snacks purchased. The results of the present study demonstrate that depletion sensitivity predicts the amount of unhealthy (but not healthy) snacks bought. The more sensitive people are to depletion, the more unhealthy snacks they buy. Moreover, there was some tentative evidence that this relation is more pronounced for people with a weak as opposed to a strong goal to lose weight, suggesting that a strong goal to lose weight may function as a motivational buffer against self-control failures. All in all, these findings provide evidence for the external validity of depletion sensitivity and the relevance of this construct in the domain of eating behavior. PMID:26321417

  18. The New MCNP6 Depletion Capability

    Energy Technology Data Exchange (ETDEWEB)

    Fensin, Michael Lorne [Los Alamos National Laboratory; James, Michael R. [Los Alamos National Laboratory; Hendricks, John S. [Los Alamos National Laboratory; Goorley, John T. [Los Alamos National Laboratory

    2012-06-19

    The first MCNP based inline Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology.

  19. The calpain, caspase 12, caspase 3 cascade leading to apoptosis is altered in F508del-CFTR expressing cells.

    Directory of Open Access Journals (Sweden)

    Mathieu Kerbiriou

    Full Text Available In cystic fibrosis (CF, the most frequent mutant variant of the cystic fibrosis transmembrane conductance regulator (CFTR, F508del-CFTR protein, is misfolded and retained in the endoplasmic reticulum (ER. We previously showed that the unfolded protein response (UPR may be triggered in CF. Since prolonged UPR activation leads to apoptosis via the calcium-calpain-caspase-12-caspase-3 cascade and because apoptosis is altered in CF, our aim was to compare the ER stress-induced apoptosis pathway between wild type (Wt and F508del-CFTR expressing cells. Here we show that the calcium-calpain-caspase-12-caspase-3 cascade is altered in F508del-CFTR expressing cells. We propose that this alteration is involved in the altered apoptosis triggering observed in CF.

  20. Depletable resources and the economy.

    NARCIS (Netherlands)

    Heijman, W.J.M.

    1991-01-01

    The subject of this thesis is the depletion of scarce resources. The main question to be answered is how to avoid future resource crises. After dealing with the complex relation between nature and economics, three important concepts in relation with resource depletion are discussed: steady state, ti

  1. The Toxicity of Depleted Uranium

    Directory of Open Access Journals (Sweden)

    Wayne Briner

    2010-01-01

    Full Text Available Depleted uranium (DU is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed.

  2. Analysis of CFTR Gene Mutations in Children with Cystic Fibrosis, First Report from North-East of Iran

    OpenAIRE

    Atieh Mehdizadeh Hakkak; Mohammad Keramatipour; Saeid Talebi; Azam Brook; Jalil Tavakol Afshari; Amin Raazi; Hamid Reza Kianifar

    2013-01-01

     Objective(s):  More than 1500 registered mutations in cystic fibrosis transmembrane regulator (CFTR) gene are responsible for dysfunction of an ion channel protein and a wide spectrum of clinical manifestations in patients with cystic fibrosis (CF). This study was performed to investigate the frequency of a number of well-known CFTR mutations in North Eastern Iranian CF patients. Material and Methods: A total number of 56 documented CF patients participated in this study. Peripheral blood...

  3. The Novel CFTR Mutation A457P in a Male with a Delayed Diagnosis of Cystic Fibrosis

    OpenAIRE

    Zuckerman, Jonathan B.; Yarmus, Lonny B.; Sosnay, Patrick R.; Cole, Kate H.

    2011-01-01

    Cystic fibrosis (CF) is an autosomal recessive disease that may be caused by more than 1000 different mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. We describe the case of a CF patient who was initially diagnosed at 16 years of age after presenting with mild respiratory compromise and pancreatic sufficiency. When genetic testing was first performed using a CF mutation panel, only a single F508del CFTR allele was identified. We subsequently performed testing...

  4. 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...

  5. Analysis of Y chromosome microdeletions and CFTR gene mutations as genetic markers of infertility in Serbian men

    OpenAIRE

    Dinić Jelena; Kušić Jelena; Nikolić Аleksandra; Divac Aleksandra; Ristanović Momčilo; Radojković Dragica

    2007-01-01

    Background/Aim. Impaired fertility of a male partner is the main cause of infertility in up to one half of all infertile couples. At the genetic level, male infertility can be caused by chromosome aberrations or gene mutations. The presence and types of Y chromosome microdeletions and cystic fybrosis transmembrane conductance regulator (CFTR) gene mutations as genetic cause of male infertility was tested in Serbian men. The aim of this study was to analyze CFTR gene mutations and Y chromosome...

  6. Depletion of the nuclear Fermi sea

    CERN Document Server

    Rios, A; Dickhoff, W H

    2009-01-01

    The short-range and tensor components of the bare nucleon-nucleon interaction induce a sizeable depletion of low momenta in the ground state of a nuclear many-body system. The self-consistent Green's function method within the ladder approximation provides an \\textit{ab-initio} description of correlated nuclear systems that accounts properly for these effects. The momentum distribution predicted by this approach is analyzed in detail, with emphasis on the depletion of the lowest momentum state. The temperature, density, and nucleon asymmetry (isospin) dependence of the depletion of the Fermi sea is clarified. A connection is established between the momentum distribution and the time-ordered components of the self-energy, which allows for an improved interpretation of the results. The dependence on the underlying nucleon-nucleon interaction provides quantitative estimates of the importance of short-range and tensor correlations in nuclear systems.

  7. Molten-Salt Depleted-Uranium Reactor

    CERN Document Server

    Dong, Bao-Guo; Gu, Ji-Yuan

    2015-01-01

    The supercritical, reactor core melting and nuclear fuel leaking accidents have troubled fission reactors for decades, and greatly limit their extensive applications. Now these troubles are still open. Here we first show a possible perfect reactor, Molten-Salt Depleted-Uranium Reactor which is no above accident trouble. We found this reactor could be realized in practical applications in terms of all of the scientific principle, principle of operation, technology, and engineering. Our results demonstrate how these reactors can possess and realize extraordinary excellent characteristics, no prompt critical, long-term safe and stable operation with negative feedback, closed uranium-plutonium cycle chain within the vessel, normal operation only with depleted-uranium, and depleted-uranium high burnup in reality, to realize with fission nuclear energy sufficiently satisfying humanity long-term energy resource needs, as well as thoroughly solve the challenges of nuclear criticality safety, uranium resource insuffic...

  8. Depleted uranium and the Gulf War syndrome

    International Nuclear Information System (INIS)

    Some military personnel involved in the 1991Gulf War have complained of continuing stress-like symptoms for which no obvious cause has been found. These symptoms have at times been attributed to the use of depleted uranium (DU) in shell casings which are believed to have caused toxic effects. Depleted uranium is natural uranium which is depleted in the rarer U-235 isotope. It is a heavy metal and in common with other heavy metals is chemically toxic. It is also slightly radioactive and could give rise to a radiological hazard if dispersed in finely divided form so that it was inhaled. In response to concerns, the possible effects of DU have been extensively studied along with other possible contributors to Gulf War sickness. This article looks at the results of some of the research that has been done on DU. (author)

  9. Depleted uranium speciation in the Bratoselce soil

    International Nuclear Information System (INIS)

    During the air strikes in 1999, about thirteen hundred projectiles with depleted uranium were fired into the Bratoselce, South Serbia. A study providing insight into physical chemical behaviour of depleted uranium originated from dissolved 'material' of projectile penetrators in the contaminated soil have been conducted. Samples were treated according to Tarriers modified procedure of five-step sequential extraction. Suitable choice of solvents for sequential extraction simulated the real conditions in the environment. Fractions are further analysed by alpha spectrometry and atomic absorption spectrometry methods to determine the uranium isotopes and trace or major elements. The results indicated potential substrates for depleted uranium compounds in the investigated environment, with specific soil composition that is essential for prediction of its mobility and bioavailability in certain conditions. (author)

  10. Lack of CFTR in skeletal muscle predisposes to muscle wasting and diaphragm muscle pump failure in cystic fibrosis mice.

    Directory of Open Access Journals (Sweden)

    Maziar Divangahi

    2009-07-01

    Full Text Available Cystic fibrosis (CF patients often have reduced mass and strength of skeletal muscles, including the diaphragm, the primary muscle of respiration. Here we show that lack of the CF transmembrane conductance regulator (CFTR plays an intrinsic role in skeletal muscle atrophy and dysfunction. In normal murine and human skeletal muscle, CFTR is expressed and co-localized with sarcoplasmic reticulum-associated proteins. CFTR-deficient myotubes exhibit augmented levels of intracellular calcium after KCl-induced depolarization, and exposure to an inflammatory milieu induces excessive NF-kB translocation and cytokine/chemokine gene upregulation. To determine the effects of an inflammatory environment in vivo, sustained pulmonary infection with Pseudomonas aeruginosa was produced, and under these conditions diaphragmatic force-generating capacity is selectively reduced in Cftr(-/- mice. This is associated with exaggerated pro-inflammatory cytokine expression as well as upregulation of the E3 ubiquitin ligases (MuRF1 and atrogin-1 involved in muscle atrophy. We conclude that an intrinsic alteration of function is linked to the absence of CFTR from skeletal muscle, leading to dysregulated calcium homeostasis, augmented inflammatory/atrophic gene expression signatures, and increased diaphragmatic weakness during pulmonary infection. These findings reveal a previously unrecognized role for CFTR in skeletal muscle function that may have major implications for the pathogenesis of cachexia and respiratory muscle pump failure in CF patients.

  11. EPAC1 activation by cAMP stabilizes CFTR at the membrane by promoting its interaction with NHERF1.

    Science.gov (United States)

    Lobo, Miguel J; Amaral, Margarida D; Zaccolo, Manuela; Farinha, Carlos M

    2016-07-01

    Cyclic AMP (cAMP) activates protein kinase A (PKA) but also the guanine nucleotide exchange factor 'exchange protein directly activated by cAMP' (EPAC1; also known as RAPGEF3). Although phosphorylation by PKA is known to regulate CFTR channel gating - the protein defective in cystic fibrosis - the contribution of EPAC1 to CFTR regulation remains largely undefined. Here, we demonstrate that in human airway epithelial cells, cAMP signaling through EPAC1 promotes CFTR stabilization at the plasma membrane by attenuating its endocytosis, independently of PKA activation. EPAC1 and CFTR colocalize and interact through protein adaptor NHERF1 (also known as SLC9A3R1). This interaction is promoted by EPAC1 activation, triggering its translocation to the plasma membrane and binding to NHERF1. Our findings identify a new CFTR-interacting protein and demonstrate that cAMP activates CFTR through two different but complementary pathways - the well-known PKA-dependent channel gating pathway and a new mechanism regulating endocytosis that involves EPAC1. The latter might constitute a novel therapeutic target for treatment of cystic fibrosis. PMID:27206858

  12. SRP scientific meeting: depleted uranium

    International Nuclear Information System (INIS)

    The meeting was organised by the SRP to review current research and discuss the use, dispersion into the environment and radiological impact of depleted uranium (DU) by the UK and US in recent military conflicts. In addition to other presentations, there were two short presentations by T Cabianca and P Danesi of the IAEA concerning investigations into the DU legacy in Kuwait and the IAEA contribution to environmental contamination assessments of DU in Kosovo. In Kuwait the on-going study is limited to an assessment of the potential radiological consequences of DU residues in three types of site: open desert where DU was fired, farmland where DU was fired and DU storage facilities. The Kuwaiti government has also requested the IAEA to formulate a structured approach to deal with remediating such sites and disposing of the resulting material. In Kosovo the study investigated sand and soil samples from areas where DU had been fired. DU particulates were found in sizes up to 40 μm, but generally much smaller, typically about 5 μm, with 5% less than 1.5 μm in size. These particles were found to contain 90% DU and 1% Ti. Plutonium was also detected, but this was attributed to the 1960s bomb testing programme. This was an informative, well attended meeting that stimulated varied debate between delegates. It revealed that there is still much to learn concerning the effects of depleted uranium in the human body and highlighted the limitations of conventional dose estimates made using ICRP models. A balance must be struck between the operational requirements of the armed forces and acceptable levels of environmental contamination arising from any conflict they are involved in. Most importantly, as a scientific consensus is developed, a clear and consistent approach to providing key information to the public should be adopted, to build confidence in the radiation protection profession

  13. ATP and AMP Mutually Influence Their Interaction with the ATP-binding Cassette (ABC) Adenylate Kinase Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) at Separate Binding Sites*

    OpenAIRE

    Randak, Christoph O.; Dong, Qian; Ver Heul, Amanda R.; Elcock, Adrian H.; Welsh, Michael J.

    2013-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel in the ATP-binding cassette (ABC) transporter protein family. In the presence of ATP and physiologically relevant concentrations of AMP, CFTR exhibits adenylate kinase activity (ATP + AMP ⇆ 2 ADP). Previous studies suggested that the interaction of nucleotide triphosphate with CFTR at ATP-binding site 2 is required for this activity. Two other ABC proteins, Rad50 and a structural maintenance of chromosome protein, ...

  14. Role of curcurmin in acute lung injury by acute pulmonary embolism and expression of CFTR%姜黄素对急性肺动脉栓塞大鼠肺损伤及CFTR表达的影响

    Institute of Scientific and Technical Information of China (English)

    王征; 玉寒冰; 罗全

    2014-01-01

    目的:观察姜黄素对急性肺栓塞大鼠肺损伤的保护作用及对CFTR表达的影响。方法:大鼠分为假手术组,模型组,姜黄素(150mg/kg)﹢APE组。制备左肺动脉结扎模拟急性肺动脉栓塞模型。进行血气分析,检测AFC及肺湿干比,real-time PCR方法检测肺组织的CFTR的表达。结果:与模型组比较,姜黄素升高PaO2水平,减轻AFC下降趋势,及减少肺湿干比的增加。姜黄素能提高肺组织的CFTR的表达。结论:姜黄素对急性肺动脉栓塞大鼠的急性肺损伤有保护作用,并上调CFTR的表达。%Objective:To observe whether the curcumin could protect the acute lung injury by acute lung embolism and affect the expression of CFTR. Methods:SPF rats were divided into 3 groups:sham group,acute pulmonary em-bolism(APE)group and curcumin group(150mg/kg). The model of acute pulmonary embolism was ligatured the left artery. Blood gas analysis,AFC and wet-to-dry ratio and CFTR mRNA expression were observed. Results:Curcu-min could increase artery O2 pressure,decrease the AFC downward and wet-to-dry ratio. Curcumin could increase the expression of CFTR mRNA. Conculsion:Curcumin could protect the acute lung injury by APE and associated with upward of CFTR mRNA.

  15. Development of heavy concrete mixed with depleted uranium

    International Nuclear Information System (INIS)

    Compressive strength and shielding performance tests of heavy weight concrete mixed with depleted Uranium (Depleted Uranium Concrete) were carried out. The depleted uranium pellets (φ 8 mm, height 9.5 mm) were mixed into cement paste instead of coarse aggregate. Specimens with nominal specific gravity of 3.2 - 5.4 were manufactured. The results of the compression strength test showed that compressive strength of more than 30 MPa was obtained with the specimens having the nominal specific gravity of more than 5 and it was confirmed from the shielding performance tests that Depleted Uranium Concrete has shielding corresponding to its nominal specific gravity. (author)

  16. Depletable resources and the economy.

    OpenAIRE

    Heijman, W. J. M.

    1991-01-01

    The subject of this thesis is the depletion of scarce resources. The main question to be answered is how to avoid future resource crises. After dealing with the complex relation between nature and economics, three important concepts in relation with resource depletion are discussed: steady state, time preference and efficiency.For the steady state, three variants are distinguished; the stationary state, the physical steady state and the state of steady growth. It is concluded that the so-call...

  17. Inflammation and CFTR: Might Neutrophils be the Key in Cystic Fibrosis?

    OpenAIRE

    Witko-Sarsat, V; Sermet-Gaudelus, I; Lenoir, G.; Descamps-Latscha, B

    1999-01-01

    The aim of this hypothesis is to provide new insights into the still unclear mechanisms governing airway inflammation in cystic fibrosis. Although the genetic basis of cystic fibrosis as well as the molecular structure of cystic fibrosis transmembrane regulator (CFTR), the mutated protein which causes the disease, have been well defined, a clear relationship between the genetic defect and the pulmonary pathophysiology, especially chronic infections and neutrophil-dominated airway inflammation...

  18. Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations in allergic bronchopulmonary aspergillosis.

    OpenAIRE

    Miller, P. W.; Hamosh, A.; Macek, M.; Greenberger, P. A.; MacLean, J; Walden, S M; Slavin, R G; Cutting, G R

    1996-01-01

    The etiology of allergic bronchopulmonary aspergillosis (ABPA) is not well understood. A clinical phenotype resembling the pulmonary disease seen in cystic fibrosis (CF) patients can occur in some individuals with ABPA. Reports of familial occurrence of ABPA and increased incidence in CF patients suggest a possible genetic basis for the disease. To test this possibility, the entire coding region of the cystic fibrosis transmembrane regulator (CFTR) gene was analyzed in 11 individuals who met ...

  19. Impact of Cystic Fibrosis Transmembrane Regulator (CFTR) gene mutations on male infertility

    OpenAIRE

    Jlenia Elia; Rossella Mazzilli; Michele Delfino; Maria Piane; Cristina Bozzao; Vincenzo Spinosa; Luciana Chessa; Fernando Mazzilli

    2014-01-01

    Objective. The aim of this study was to evaluate the prevalence of most common mutations and intron 8 5T (IVS8-5T) polymorphism of CFTR gene in Italian: a) azoospermic males; b) non azoospermic subjects, male partners of infertile couples enrolled in assisted reproductive technology (ART) programs. Material and methods. We studied 242 subjects attending our Andrology Unit (44 azoospermic subjects and 198 non azoospermic subjects, male partners of infertile couples enrolled in ART programs). S...

  20. Phosphorylation of CFTR and other membrane proteins: a role in biogenesis and traffic?

    OpenAIRE

    Romeiras, Francisco Maria de Sousa de Macedo Malta, 1986-

    2009-01-01

    Tese de mestrado, Bioquímica (Bioquímica Médica), Universidade de Lisboa, Faculdade de Ciências, 2009 Cystic Fibrosis (CF), the most common lethal autosomal recessive disorder among Caucasians, is caused by mutations in the gene that encodes for the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). With more than 1600 mutations reported, a single mutation– the deletion of phenylalanine residue at position 508 – accounts for more than 70% of chromosomes worldwide. The presence of ...

  1. Regulation of CFTR Cl− channel gating by ATP binding and hydrolysis

    OpenAIRE

    Ikuma, Mutsuhiro; Welsh, Michael J.

    2000-01-01

    Opening and closing of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel is regulated by the interaction of ATP with its two cytoplasmic nucleotide-binding domains (NBD). Although ATP hydrolysis by the NBDs is required for normal gating, the influence of ATP binding versus hydrolysis on specific steps in the gating cycle remains uncertain. Earlier work showed that the absence of Mg2+ prevents hydrolysis. We found that even in the absence of Mg2+, ATP could support cha...

  2. The power stroke driven by ATP binding in CFTR as studied by molecular dynamics simulations.

    Science.gov (United States)

    Furukawa-Hagiya, Tomoka; Furuta, Tadaomi; Chiba, Shuntaro; Sohma, Yoshiro; Sakurai, Minoru

    2013-01-10

    Cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride channel belonging to the ATP binding cassette (ABC) protein superfamily. Currently, it remains unclear how ATP binding causes the opening of the channel gate at the molecular level. To clarify this mechanism, we first constructed an atomic model of the inward-facing CFTR using the X-ray structures of other ABC proteins. Molecular dynamics (MD) simulations were then performed to explore the structure and dynamics of the inward-facing CFTR in a membrane environment. In the MgATP-bound state, two nucleotide-binding domains (NBDs) formed a head-to-tail type of dimer, in which the ATP molecules were sandwiched between the Walker A and signature motifs. Alternatively, one of the final MD structures in the apo state was similar to that of a "closed-apo" conformation found in the X-ray analysis of ATP-free MsbA. Principal component analysis for the MD trajectory indicated that NBD dimerization causes significant structural and dynamical changes in the transmembrane domains (TMDs), which is likely indicative of the formation of a chloride ion access path. This study suggests that the free energy gain from ATP binding acts as a driving force not only for NBD dimerization but also for NBD-TMD concerted motions. PMID:23214920

  3. Detection of phospho-sites generated by protein kinase CK2 in CFTR: mechanistic aspects of Thr1471 phosphorylation.

    Directory of Open Access Journals (Sweden)

    Andrea Venerando

    Full Text Available By mass spectrometry analysis of mouse Cystic Fibrosis Transmembrane-conductance Regulator (mCFTR expressed in yeast we have detected 21 phosphopeptides accounting for 22 potential phospho-residues, 12 of which could be unambiguously assigned. Most are conserved in human CFTR (hCFTR and the majority cluster in the Regulatory Domain, lying within consensus sequences for PKA, as identified in previous mammalian studies. This validates our yeast expression model. A number of phospho-residues were novel and human conserved, notably mouse Ser670, Ser723, Ser737, and Thr1467, that all lie in acidic sequences, compatible with their phosphorylation by protein kinase CK2. Thr1467 is localized in the C-terminal tail, embedded in a functionally important and very acidic sequence (EETEEE which displays an optimal consensus for protein kinase CK2. Herein, we show that Thr1467, homologous to human Thr1471 is readily phosphorylated by CK2. Indeed a 42 amino acid peptide encompassing the C-terminal segment of human CFTR is readily phosphorylated at Thr1471 with favorable kinetics (Km 1.7 µM by CK2 holoenzyme, but neither by its isolated catalytic subunit nor by other acidophilic Ser/Thr kinases (CK1, PLK2/3, GCK/FAM20C. Our finding that by treating CFTR expressing BHK cells with the very specific CK2 inhibitor CX4945, newly synthesized wild type CFTR (and even more its Phe508del mutant accumulates more abundantly than in the absence of CK2 inhibitor, supports the conclusion that phosphorylation of CFTR by CK2 correlates with decreased stability of the protein.

  4. PTTG mRNA和CFTR mRNA在慢性胰腺炎和胰腺癌鉴别诊断中的应用

    Institute of Scientific and Technical Information of China (English)

    李雅萍

    2015-01-01

    Objective To explore the application of PTTG mRNA and CFTR mRNA in the differential diagnosis of chronic pancreatitis and pancreatic cancer. Method 20 cases of patients with chronic pancreatitis and 30 cases of patients with pancreatic cancer were selected. The expression of organize PTTG mRNA and CFTRmRNA in the two groups was detected,real-time reverse transcription-polymerase chain reaction(RT-PCR) technology was applied. The changes of the two markers were comparetively analysed. Results The expression rate of CFTRmRNA in chronic pancreatitis group and PTTGmRNA in pancreatic cancer group was respectively obviously higher(P<0.01). The expression quantity of PTTGmRNA and CFTRmRNA in chronic pancreatitis and pancreatic cancer were in the correlation(r=-0.526,-0.539,P<0.01). Conclution PTTGmRNA has higher sensitivity in diagnosis of pancreatic cancer,so does CFTRmRNA in diagnosis of chronic pancreatitis. Testing organization PTTGmRNA and CFTRmRNA can be used in the differential diagnosis of chronic pancreatitis and pancreatic cancer disease.%目的:探讨垂体肿瘤转化基因(PTTG)mRNA和囊性纤维跨膜转运调节因子(CFTR)mRNA在慢性胰腺炎和胰腺癌疾病中的变化及临床意义。方法选择慢性胰腺炎患者20例,胰腺癌患者30例;采用实时逆转录-聚合酶链反应(RT-PCR)技术检测两组组织中PTTG mRNA和CFTR mRNA表达状况,比较分析两标志物的变化。结果慢性胰腺炎组织中CFTR mRNA的表达水平明显高于胰腺癌(P<0.01), PTTG mRNA在慢性胰腺炎组织中的表达水平明显低于胰腺癌(P<0.01)。PTTG mRNA和CFTR mRNA在慢性胰腺炎和胰腺癌组织中的表达量具有相关性(r=-0.526、-0.539,P<0.01)。结论检测PTTG mRNA表达水平可用于胰腺癌诊断,检测CFTR mRNA表达水平可用于慢性胰腺炎诊断,且均具有较强的灵敏性。

  5. ホスファチジン酸による CFTR の細胞内輸送制御機構および CFTR 機能破綻により生じる掻痒病態発症機構の解明

    OpenAIRE

    橋本, 泰明; ハシモト, ヤスアキ; Hashimoto, Yasuaki

    2008-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) in which mutation isthe cause of cystic fibrosis (CF) is a polytopic integral membrane protein that mediatestransepithelial chloride transport across epithelial cells in airways, pancreas, intestines andsweat glands. In addition, CFTR also regulates other various molecules (ion channels andreceptors) such as ENaC by forming multimolecular complex called “Transportsome”.Therefore, CFTR molecule is an extremely important molecule fo...

  6. Barium depletion study on impregnated cathodes and lifetime prediction

    Science.gov (United States)

    Roquais, J. M.; Poret, F.; le Doze, R.; Ricaud, J. L.; Monterrin, A.; Steinbrunn, A.

    2003-06-01

    In the thermionic cathodes used in cathode ray-tubes (CRTs), barium is the key element for the electronic emission. In the case of the dispenser cathodes made of a porous tungsten pellet impregnated with Ba, Ca aluminates, the evaporation of Ba determines the cathode lifetime with respect to emission performance in the CRT. The Ba evaporation results in progressive depletion of the impregnating material inside the pellet. In the present work, the Ba depletion with time has been extensively characterized over a large range of cathode temperature. Calculations using the depletion data allowed modeling of the depletion as a function of key parameters. The link between measured depletion and emission in tubes has been established, from which an end-of-life criterion was deduced. Taking modeling into account, predicting accelerated life-tests were performed using high-density maximum emission current (MIK).

  7. Barium depletion study on impregnated cathodes and lifetime prediction

    International Nuclear Information System (INIS)

    In the thermionic cathodes used in cathode ray-tubes (CRTs), barium is the key element for the electronic emission. In the case of the dispenser cathodes made of a porous tungsten pellet impregnated with Ba, Ca aluminates, the evaporation of Ba determines the cathode lifetime with respect to emission performance in the CRT. The Ba evaporation results in progressive depletion of the impregnating material inside the pellet. In the present work, the Ba depletion with time has been extensively characterized over a large range of cathode temperature. Calculations using the depletion data allowed modeling of the depletion as a function of key parameters. The link between measured depletion and emission in tubes has been established, from which an end-of-life criterion was deduced. Taking modeling into account, predicting accelerated life-tests were performed using high-density maximum emission current (MIK)

  8. Reactor fuel depletion benchmark of TINDER

    International Nuclear Information System (INIS)

    Highlights: • A reactor burnup benchmark of TINDER, coupling MCNP6 to CINDER2008, was performed. • TINDER is a poor candidate for fuel depletion calculations using its current libraries. • Data library modification is necessary if fuel depletion is desired from TINDER. - Abstract: Accurate burnup calculations are key to proper nuclear reactor design, fuel cycle modeling, and disposal estimations. The TINDER code, originally designed for activation analyses, has been modified to handle full burnup calculations, including the widely used predictor–corrector feature. In order to properly characterize the performance of TINDER for this application, a benchmark calculation was performed. Although the results followed the trends of past benchmarked codes for a UO2 PWR fuel sample from the Takahama-3 reactor, there were obvious deficiencies in the final result, likely in the nuclear data library that was used. Isotopic comparisons versus experiment and past code benchmarks are given, as well as hypothesized areas of deficiency and future work

  9. A worldwide view of groundwater depletion

    Science.gov (United States)

    van Beek, L. P.; Wada, Y.; van Kempen, C.; Reckman, J. W.; Vasak, S.; Bierkens, M. F.

    2010-12-01

    During the last decades, global water demand has increased two-fold due to increasing population, expanding irrigated area and economic development. Globally such demand can be met by surface water availability (i.e., water in rivers, lakes and reservoirs) but regional variations are large and the absence of sufficient rainfall and run-off increasingly encourages the use of groundwater resources, particularly in the (semi-)arid regions of the world. Excessive abstraction for irrigation frequently leads to overexploitation, i.e. if groundwater abstraction exceeds the natural groundwater recharge over extensive areas and prolonged times, persistent groundwater depletion may occur. Observations and various regional studies have revealed that groundwater depletion is a substantial issue in regions such as Northwest India, Northeast Pakistan, Central USA, Northeast China and Iran. Here we provide a global overview of groundwater depletion from the year 1960 to 2000 at a spatial resolution of 0.5 degree by assessing groundwater recharge with the global hydrological model PCR-GLOBWB and subtracting estimates of groundwater abstraction obtained from IGRAC-GGIS database. PCR-GLOBWB was forced by the CRU climate dataset downscaled to daily time steps using ERA40 re-analysis data. PCR-GLOBWB simulates daily global groundwater recharge (0.5 degree) while considering sub-grid variability of each grid cell (e.g., short and tall vegetation, different soil types, fraction of saturated soil). Country statistics of groundwater abstraction were downscaled to 0.5 degree by using water demand (i.e., agriculture, industry and domestic) as a proxy. To limit problems related to increased capture of discharge and increased recharge due to groundwater pumping, we restricted our analysis to sub-humid to arid areas. The uncertainty in the resulting estimates was assessed by a Monte Carlo analysis of 100 realizations of groundwater recharge and 100 realizations of groundwater abstraction

  10. Molten-Salt Depleted-Uranium Reactor

    OpenAIRE

    Dong, Bao-Guo; Dong, Pei; Gu, Ji-Yuan

    2015-01-01

    The supercritical, reactor core melting and nuclear fuel leaking accidents have troubled fission reactors for decades, and greatly limit their extensive applications. Now these troubles are still open. Here we first show a possible perfect reactor, Molten-Salt Depleted-Uranium Reactor which is no above accident trouble. We found this reactor could be realized in practical applications in terms of all of the scientific principle, principle of operation, technology, and engineering. Our results...

  11. Tank depletion flow instruments

    International Nuclear Information System (INIS)

    A new flowmetering system is developed to measure and control flow without the need for an inline flowmeter. Flowrate is determined from the rate of level change in reference vessel. This system is unique in its use of balance pots for zero suppression to enable range amplification. The result is an accuracy in flow measurement and control as good as $plus or minus$1%. The system uses state-of-the-art digital integrated circuits with a crystal time base in conjunction with the time-proven pneumatic bubbler probe low range transmitters. The benefits are (1) reduced radiation exposure to personnel during maintenance of flowmeters for radioactive streams since instruments are all located in an operating area isolated from the process by four feet of concrete, (2) reduced volume of solid nuclear wastes through processing efficiencies, (3) reduced cost of chemicals involved, (4) increased speed of flowrate determination, (5) reduced maintenance time and material cost to correct flow instrument component failures, (6) no obstruction to flow in the process stream, and (7) reduced cost of instrumentation to determine flowrate. A disadvantage is the requirement that flow must be related to tank level thus only one unknown flow into or out of a given vessel at a time may be metered and controlled. 1 ref

  12. Health and environmental impact of depleted uranium

    International Nuclear Information System (INIS)

    Depleted Uranium (DU) is 'nuclear waste' produced from the enrichment process and is mostly made up of 238U and is depleted in the fissionable isotope 235U compared to natural uranium (NU). Depleted uranium has about 60% of the radioactivity of natural uranium. Depleted uranium and natural uranium are identical in terms of the chemical toxicity. Uranium's high density gives depleted uranium shells increased range and penetrative power. This density, combined with uranium's pyrophoric nature, results in a high-energy kinetic weapon that can punch and burn through armour plating. Striking a hard target, depleted uranium munitions create extremely high temperatures. The uranium immediately burns and vaporizes into an aerosol, which is easily diffused in the environment. People can inhale the micro-particles of uranium oxide in an aerosol and absorb them mainly from lung. Depleted uranium has both aspects of radiological toxicity and chemical toxicity. The possible synergistic effect of both kinds of toxicities is also pointed out. Animal and cellular studies have been reported the carcinogenic, neurotoxic, immuno-toxic and some other effects of depleted uranium including the damage on reproductive system and foetus. In addition, the health effects of micro/ nano-particles, similar in size of depleted uranium aerosols produced by uranium weapons, have been reported. Aerosolized DU dust can easily spread over the battlefield spreading over civilian areas, sometimes even crossing international borders. Therefore, not only the military personnel but also the civilians can be exposed. The contamination continues after the cessation of hostilities. Taking these aspects into account, DU weapon is illegal under international humanitarian laws and is considered as one of the inhumane weapons of 'indiscriminate destruction'. The international society is now discussing the prohibition of DU weapons based on 'precautionary principle'. The 1991 Gulf War is reportedly the first

  13. DOPAMINE DEPLETION SLOWS RETINAL TRANSMISSION

    Science.gov (United States)

    In male hooded rats, depletion of norepinephrine and dopamine by a-methyl-paratyrosine (AMT) significantly increased the latencies of early peaks in flash-evoked potentials recorded from the visual cortex, lateral geniculate nucleus, and optic tract. These effects were not produc...

  14. Iron Depletion into Dust Grains in Galactic Planetary Nebulae

    CERN Document Server

    Delgado-Inglada, G

    2010-01-01

    We present preliminary results of an analysis of the iron depletion factor into dust grains for a sample of 20 planetary nebulae (PNe) from the Galactic bulge. We compare these results with the ones we obtained in a prior analysis of 28 Galactic disk PNe and 8 Galactic H II regions. We derive high depletion factors in all the objects, suggesting that more than 80% of their iron atoms are condensed into dust grains. The range of iron depletions in the sample PNe covers about two orders of magnitude, and we explore here if the differences are related to the PN morphology. However, we do not find any significant correlation.

  15. Improvements in EBR-2 core depletion calculations

    International Nuclear Information System (INIS)

    The need for accurate core depletion calculations in Experimental Breeder Reactor No. 2 (EBR-2) is discussed. Because of the unique physics characteristics of EBR-2, it is difficult to obtain accurate and computationally efficient multigroup flux predictions. This paper describes the effect of various conventional and higher order schemes for group constant generation and for flux computations; results indicate that higher-order methods are required, particularly in the outer regions (i.e. the radial blanket). A methodology based on Nodal Equivalence Theory (N.E.T.) is developed which allows retention of the accuracy of a higher order solution with the computational efficiency of a few group nodal diffusion solution. The application of this methodology to three-dimensional EBR-2 flux predictions is demonstrated; this improved methodology allows accurate core depletion calculations at reasonable cost. 13 refs., 4 figs., 3 tabs

  16. Thermal unfolding studies show the disease causing F508del mutation in CFTR thermodynamically destabilizes nucleotide-binding domain 1

    Science.gov (United States)

    Protasevich, Irina; Yang, Zhengrong; Wang, Chi; Atwell, Shane; Zhao, Xun; Emtage, Spencer; Wetmore, Diana; Hunt, John F; Brouillette, Christie G

    2010-01-01

    Misfolding and degradation of CFTR is the cause of disease in patients with the most prevalent CFTR mutation, an in-frame deletion of phenylalanine (F508del), located in the first nucleotide-binding domain of human CFTR (hNBD1). Studies of (F508del)CFTR cellular folding suggest that both intra- and inter-domain folding is impaired. (F508del)CFTR is a temperature-sensitive mutant, that is, lowering growth temperature, improves both export, and plasma membrane residence times. Yet, paradoxically, F508del does not alter the fold of isolated hNBD1 nor did it seem to perturb its unfolding transition in previous isothermal chemical denaturation studies. We therefore studied the in vitro thermal unfolding of matched hNBD1 constructs ±F508del to shed light on the defective folding mechanism and the basis for the thermal instability of (F508del)CFTR. Using primarily differential scanning calorimetry (DSC) and circular dichroism, we show for all hNBD1 pairs studied, that F508del lowers the unfolding transition temperature (Tm) by 6–7°C and that unfolding occurs via a kinetically-controlled, irreversible transition in isolated monomers. A thermal unfolding mechanism is derived from nonlinear least squares fitting of comprehensive DSC data sets. All data are consistent with a simple three-state thermal unfolding mechanism for hNBD1 ± F508del: N(±MgATP) ⇄ IT(±MgATP) → AT → (AT)n. The equilibrium unfolding to intermediate, IT, is followed by the rate-determining, irreversible formation of a partially folded, aggregation-prone, monomeric state, AT, for which aggregation to (AT)n and further unfolding occur with no detectable heat change. Fitted parameters indicate that F508del thermodynamically destabilizes the native state, N, and accelerates the formation of AT. PMID:20687133

  17. Correction of chloride transport and mislocalization of CFTR protein by vardenafil in the gastrointestinal tract of cystic fibrosis mice.

    Directory of Open Access Journals (Sweden)

    Barbara Dhooghe

    Full Text Available Although lung disease is the major cause of mortality in cystic fibrosis (CF, gastrointestinal (GI manifestations are the first hallmarks in 15-20% of affected newborns presenting with meconium ileus, and remain major causes of morbidity throughout life. We have previously shown that cGMP-dependent phosphodiesterase type 5 (PDE5 inhibitors rescue defective CF Transmembrane conductance Regulator (CFTR-dependent chloride transport across the mouse CF nasal mucosa. Using F508del-CF mice, we examined the transrectal potential difference 1 hour after intraperitoneal injection of the PDE5 inhibitor vardenafil or saline to assess the amiloride-sensitive sodium transport and the chloride gradient and forskolin-dependent chloride transport across the GI tract. In the same conditions, we performed immunohistostaining studies in distal colon to investigate CFTR expression and localization. F508del-CF mice displayed increased sodium transport and reduced chloride transport compared to their wild-type littermates. Vardenafil, applied at a human therapeutic dose (0.14 mg/kg used to treat erectile dysfunction, increased chloride transport in F508del-CF mice. No effect on sodium transport was detected. In crypt colonocytes of wild-type mice, the immunofluorescence CFTR signal was mostly detected in the apical cell compartment. In F508del-CF mice, a 25% reduced signal was observed, located mostly in the subapical region. Vardenafil increased the peak of intensity of the fluorescence CFTR signal in F508del-CF mice and displaced it towards the apical cell compartment. Our findings point out the intestinal mucosa as a valuable tissue to study CFTR transport function and localization and to evaluate efficacy of therapeutic strategies in CF. From our data we conclude that vardenafil mediates potentiation of the CFTR chloride channel and corrects mislocalization of the mutant protein. The study provides compelling support for targeting the cGMP signaling pathway in CF

  18. Distribution of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR Mutations in a Cohort of Patients Residing in Palestine.

    Directory of Open Access Journals (Sweden)

    Issa Siryani

    Full Text Available Cystic fibrosis (CF is an autosomal recessive inherited life-threatening disorder that causes severe damage to the lungs and the digestive system. In Palestine, mutations in the Cystic Fibrosis Transmembrane Conductance Regulator gene (CFTR that contributes to the clinical presentation of CF are ill defined. A cohort of thirty three clinically diagnosed CF patients from twenty one different Palestinian families residing in the central and southern part of Palestine were incorporated in this study. Sweat chloride testing was performed using the Sweat Chek Conductivity Analyzer (ELITECH Group, France to confirm the clinical diagnosis of CF. In addition, nucleic acid from the patients' blood samples was extracted and the CFTR mutation profiles were assessed by direct sequencing of the CFTR 27 exons and the intron-exon boundaries. For patient's DNA samples where no homozygous or two heterozygous CFTR mutations were identified by exon sequencing, DNA samples were tested for deletions or duplications using SALSA MLPA probemix P091-D1 CFTR assay. Sweat chloride testing confirmed the clinical diagnosis of CF in those patients. All patients had NaCl conductivity >60 mmol/l. In addition, nine different CFTR mutations were identified in all 21 different families evaluated. These mutations were c.1393-1G>A, F508del, W1282X, G85E, c.313delA, N1303K, deletion exons 17a-17b-18, deletion exons 17a-17b and Q1100P. c.1393-1G>A was shown to be the most frequent occurring mutation among tested families. We have profiled the underling mutations in the CFTR gene of a cohort of 21 different families affected by CF. Unlike other studies from the Arab countries where F508del was reported to be the most common mutation, in southern/central Palestine, the c.1393-1G>A appeared to be the most common. Further studies are needed per sample size and geographic distribution to account for other possible CFTR genetic alterations and their frequencies. Genotype

  19. Three charged amino acids in extracellular loop 1 are involved in maintaining the outer pore architecture of CFTR

    OpenAIRE

    Cui, Guiying; Rahman, Kazi S.; Infield, Daniel T.; Kuang, Christopher; Prince, Chengyu Z.; McCarty, Nael A.

    2014-01-01

    The cystic fibrosis (CF) transmembrane conductance regulator (CFTR) bears six extracellular loops (ECL1–6); ECL1 is the site of several mutations associated with CF. Mutation R117H has been reported to reduce current amplitude, whereas D110H, E116K, and R117C/L/P may impair channel stability. We hypothesized that these amino acids might not be directly involved in ion conduction and permeation but may contribute to stabilizing the outer vestibule architecture in CFTR. We used cRNA injected oo...

  20. Net depletion determination for Hankin Wetland Development Project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This memorandum contains the analysis and the data used to produce the net depletion that would occur as a result of the Hankin Wetland Development Project.

  1. CFTR and cystic fibrosis%CFTR与囊性纤维化

    Institute of Scientific and Technical Information of China (English)

    王瑞; 李学军

    2006-01-01

    囊性纤维化跨膜传导调节因子(CFTR)是一种cAMP激活的ATP门控性氯离子通道,表达于气道,消化道和生殖道上皮细胞的顶部质膜中.囊性纤维化(CF)是白人中最常见的遗传性疾病之一,由CFTR基因突变造成.对CFTR基因的破译使人们进一步了解CF的发病机制,并为该疾病的诊断提供了新的线索.

  2. Development of ARMS PCR tests for detection of common CFTR gene mutations

    OpenAIRE

    Livshits L. A.; Pampukha V. M.; Soloviov O. O.

    2010-01-01

    Aim. To develop diagnostic assays, based on the amplification refractory mutation system (ARMS) principle, for detection of common mutations in the CFTR gene using two approaches: standard PCR with further gel-electrophoresis and Real-Time PCR with SYBR Green. Materials. For this study we have chosen the following mutations: dF508, W1282X, R117H, 621 + 1G > T, 2143delT with the frequencies in Ukraine: dF508 – 43.3 %; 2143delT – 1.38 %; W1282X – 1.1 %; R117H, 621 + 1G > T – < 0.6 %. For the de...

  3. The ultimate disposition of depleted uranium

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-01

    Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

  4. Understanding the haling power depletion (HPD) method

    International Nuclear Information System (INIS)

    The Pennsylvania State Univ. (PSU) is using the university version of the Studsvik Scandpower Code System (CMS) for research and education purposes. Preparations have been made to incorporate the CMS into the PSU Nuclear Engineering graduate class 'Nuclear Fuel Management' course. The information presented in this paper was developed during the preparation of the material for the course. The Haling Power Depletion (HPD) was presented in the course for the first time. The HPD method has been criticized as not valid by many in the field even though it has been successfully applied at PSU for the past 20 years. It was noticed that the radial power distribution (RPD) for low leakage cores during depletion remained similar to that of the HPD during most of the cycle. Thus, the Haling Power Depletion (HPD) may be used conveniently mainly for low leakage cores. Studies were then made to better understand the HPD and the results are presented in this paper. Many different core configurations can be computed quickly with the HPD without using Burnable Poisons (BP) to produce several excellent low leakage core configurations that are viable for power production. Once the HPD core configuration is chosen for further analysis, techniques are available for establishing the BP design to prevent violating any of the safety constraints in such HPD calculated cores. In summary, in this paper it has been shown that the HPD method can be used for guiding the design for the low leakage core. (authors)

  5. Fighting self-control failure: overcoming ego depletion by increasing self-awareness

    OpenAIRE

    Alberts, Hugo J. E. M.; Martijn, Carolien; de Vries, Nanne K

    2010-01-01

    International audience According to the limited strength model (Muraven, Tice, & Baumeister, 1998), exerting self-control causes ego depletion: a depletion of cognitive resources resulting in poorer performance on later self-control tasks. Previous studies have demonstrated a positive effect of self-awareness on self-control performance. The present study examined whether the occurrence of ego depletion can be circumvented by increasing self-awareness. Initially depleted participants who r...

  6. Civil use of depleted uranium

    International Nuclear Information System (INIS)

    In this paper the civilian exploitation of depleted uranium is briefly reviewed. Different scenarios relevant to its use are discussed in terms of radiation exposure for workers and the general public. The case of the aircraft accident which occurred in Amsterdam in 1992 involving a fire, is discussed in terms of the radiological exposure to bystanders. All information given has been obtained on the basis of an extensive literature search and are not based on measurements performed at the Institute for Transuranium Elements

  7. Measurements of CFTR-mediated Cl- secretion in human rectal biopsies constitute a robust biomarker for Cystic Fibrosis diagnosis and prognosis.

    Directory of Open Access Journals (Sweden)

    Marisa Sousa

    Full Text Available BACKGROUND: Cystic Fibrosis (CF is caused by ∼1,900 mutations in the CF transmembrane conductance regulator (CFTR gene encoding for a cAMP-regulated chloride (Cl(- channel expressed in several epithelia. Clinical features are dominated by respiratory symptoms, but there is variable organ involvement thus causing diagnostic dilemmas, especially for non-classic cases. METHODOLOGY/PRINCIPAL FINDINGS: To further establish measurement of CFTR function as a sensitive and robust biomarker for diagnosis and prognosis of CF, we herein assessed cholinergic and cAMP-CFTR-mediated Cl(- secretion in 524 freshly excised rectal biopsies from 118 individuals, including patients with confirmed CF clinical diagnosis (n=51, individuals with clinical CF suspicion (n=49 and age-matched non-CF controls (n=18. Conclusive measurements were obtained for 96% of cases. Patients with "Classic CF", presenting earlier onset of symptoms, pancreatic insufficiency, severe lung disease and low Shwachman-Kulczycki scores were found to lack CFTR-mediated Cl(- secretion (<5%. Individuals with milder CF disease presented residual CFTR-mediated Cl(- secretion (10-57% and non-CF controls show CFTR-mediated Cl(- secretion ≥ 30-35% and data evidenced good correlations with various clinical parameters. Finally, comparison of these values with those in "CF suspicion" individuals allowed to confirm CF in 16/49 individuals (33% and exclude it in 28/49 (57%. Statistical discriminant analyses showed that colonic measurements of CFTR-mediated Cl(- secretion are the best discriminator among Classic/Non-Classic CF and non-CF groups. CONCLUSIONS/SIGNIFICANCE: Determination of CFTR-mediated Cl(- secretion in rectal biopsies is demonstrated here to be a sensitive, reproducible and robust predictive biomarker for the diagnosis and prognosis of CF. The method also has very high potential for (pre-clinical trials of CFTR-modulator therapies.

  8. Prediction Method of Safety Mud Density in Depleted Oilfields

    Directory of Open Access Journals (Sweden)

    Yuan Jun-Liang

    2013-04-01

    Full Text Available At present, many oilfields were placed in the middle and late development period and the reservoir pressure depleted usually, resulting in more serious differential pressure sticking and drilling mud leakage both in the reservoir and cap rock. In view of this situation, a systematic prediction method of safety mud density in depleted oilfields was established. The influence of reservoir depletion on stress and strength in reservoir and cap formation were both studied and taken into the prediction of safety mud density. The research showed that the risk of differential pressure sticking and drilling mud leakage in reservoir and cap formation were both increased and they were the main prevention object in depleted oilfields drilling. The research results were used to guide the practice drilling work, the whole progress gone smoothly.

  9. Integrated biophysical studies implicate partial unfolding of NBD1 of CFTR in the molecular pathogenesis of F508del cystic fibrosis

    OpenAIRE

    Wang, Chi; Protasevich, Irina; Yang, Zhengrong; Seehausen, Derek; Skalak, Timothy; Zhao, Xun; Atwell, Shane; Spencer Emtage, J; Wetmore, Diana R.; Brouillette, Christie G; Hunt, John F.

    2010-01-01

    The lethal genetic disease cystic fibrosis is caused predominantly by in-frame deletion of phenylalanine 508 in the cystic fibrosis transmembrane conductance regulator (CFTR). F508 is located in the first nucleotide-binding domain (NBD1) of CFTR, which functions as an ATP-gated chloride channel on the cell surface. The F508del mutation blocks CFTR export to the surface due to aberrant retention in the endoplasmic reticulum. While it was assumed that F508del interferes with NBD1 folding, bioph...

  10. Identification of Herbal Compound lmperatorin with Adverse Effects on ANO1 and CFTR Chloride Channels

    Institute of Scientific and Technical Information of China (English)

    HAO Feng; YI Fei; ZHANG Di; NING Yan; SU Wei-heng; FENG Xue-chao; YANG Hong; MA Tong-hui

    2011-01-01

    Calcium-activated chloride channels(CaCCs) are the crucial regulators of transepithelial fluid secretion,smooth muscle contraction and sensory transduction. Recently, compelling evidence has indicated that TMEM 16A(ANO 1 or anoctamin-i ) is a bona fide calcium-acvtivated chloride channel. A few small molecule CaCCs regulators are available for functional and therapeutic studies. We screened 126 natural compounds from Chinese herbs. Screening was performed with an iodide influx assay in Fischer rat thyroid epithelial cells to coexpress ANOI and an iodide-sensitive fluorescent indicator(EYFP-HI48Q/I152L). lmperatorin, a coumarin compound, was identifled to inhibit ANOl-mediated chloride transport activated by multiple calcium-elevating agonists. The inhibitory effect is dose-dependent with IC50 ~14.63 μmol/L. Interestingly, imperatorin activated CFTR chloride channel with EC50 ~35.52 μmol/L. The adverse effects of imperatorin on CaCC and CFTR chloride channels will make it useful in pharmacological dissection of chloride transport in airway and intestinal epithelium. Further studies are required to evaluate the therapeutic effects of imperatorin on hypertension, asthma and certain tumors.

  11. Cystic fibrosis and the role of gastrointestinal outcome measures in the new era of therapeutic CFTR modulation

    NARCIS (Netherlands)

    Bodewes, Frank A J A; Verkade, Henkjan J; Taminiau, Jan A J M; Borowitz, Drucy; Wilschanski, Michael

    2015-01-01

    With the development of new drugs that directly affect CFTR protein function, clinical trials are being designed or initiated for a growing number of patients with cystic fibrosis. The currently available and accepted clinical endpoints, FEV1 and BMI, have limitations. The aim of this report is to d

  12. Heterogeneity of phenotype in two cystic fibrosis patients homozygous for the CFTR exon 11 mutation G551D.

    OpenAIRE

    Parad, R B

    1996-01-01

    In the heterozygous state, the cystic fibrosis transmembrane conductance regulator (CFTR) exon 11 mutation G551D has been described as "severe," causing pancreatic insufficiency. Two cystic fibrosis (CF) patients homozygous for this mutation showed a mild rather than severe pancreatic phenotype and a variable pulmonary phenotype.

  13. Ursodeoxycholate modulates bile flow and bile salt pool independently from the cystic fibrosis transmembrane regulator (Cftr) in mice

    NARCIS (Netherlands)

    Bodewes, Frank A. J. A.; Wouthuyzen-Bakker, Marjan; Bijvelds, Marcel J.; Havinga, Rick; de Jonge, Hugo R.; Verkade, Henkjan J.

    2012-01-01

    Bodewes FAJA, Wouthuyzen-Bakker M, Bijvelds MJ, Havinga R, de Jonge HR, Verkade HJ. Ursodeoxycholate modulates bile flow and bile salt pool independently from the cystic fibrosis transmembrane regulator (Cftr) in mice. Am J Physiol Gastrointest Liver Physiol 302: G1035-G1042, 2012. First published F

  14. Comparative analysis of common CFTR polymorphisms poly-T, TG-repeats and M470V in a healthy Chinese population

    Institute of Scientific and Technical Information of China (English)

    Qin Huang; Wei Ding; Mu-Xin Wei

    2008-01-01

    AIM: To investigate the three important cystic fibrosis transmembrane conductance regulator (CFTR) haplotypes po!y-T, TG-repeats and the M470V polymorphisms in the Chinese population, and to compare their distribution with that in Caucasians and other Asian populations.METHODS: Genomic DNA was extracted from blood leukocytes. Exons 9 and 10 of the CFTR gene were obtained through polymerase chain reaction (PCR). Exon 9 DNA sequences were directly detected by an automated sequencer and poly-T and TG-repeats were identified by direct sequence analysis. Pure exon 10 PCR-amplified products were digested by Hph I restriction enzyme and the M470V mutation was detected by the AGE photos of digestion products.RESULTS: T7 was the most common (93.6%) haplotype and the (TG)ll frequency of 57.2% and (TG)12 frequency of 40.9% were dominant haplotypes in the junction of intron 8 (IVS-8) and exon 9. The frequency of T5 was 3.8% and all T5 allele tracts (10 alleles) were joined with (TG)12. Four new alleles of T6 (1.5%) were found in three healthy individuals. In exon 10, the V allele (56.1%) was slightly more frequent than the M allele (43.9%), and the M/V (45.5%) was the dominant genotype in these individuals. The three major haplotypes T7-(TG)ll-V470, T7-(TG)12-M470 and T7-TG11-M470 were related to nearly 86.0% of the population.CONCLUSION: The polymorphisms of poly-T, TG-repeats, and M470V distribution were similar to those in other East Asians, but they had marked differences in frequency from those single haplotype polymorphisms or linkage haplotypes in Caucasians. Thus, they may be able to explain the low incidence of CF and CF-like diseases in Asians.

  15. Screening and validation of specific zinc finger nucleases targeted pig CFTR gene%猪CFTR基因特异性锌指核酸酶的筛选与鉴定

    Institute of Scientific and Technical Information of China (English)

    王瑞; 王令; 林娟; 张存芳; 张智英

    2012-01-01

    to screen specific zinc finger proteins by two steps of B2H.Forty eight specific ZFPs with high affinity to the left and right half sites of CFTR target site were gained,respectively.The result of ZFN activity validation in yeast demonstrated that 90% of screened ZFN had the ability to cleave CFTR target site,and specific ZFN were achieved via this strategy.【Conclusion】The ZFN with high affinity and efficiency will be applied to target pig CFTR gene resulting in generation of CFTR gene knockout pig cell lines,which is fundamental to make the disease model for gene therapy and drug discovery.

  16. Assessment Of Depleted Uranium Contamination In Selective IRAQI Soils

    International Nuclear Information System (INIS)

    The aim of this research was to measure the radiation exposure rates in three selected Locations in southren part of Iraq (two in Nassireya, and one in Amara) resulted from the existence of depleted uranium in soil and metal pieces have been taken from destroyed tank and study mathmatically the concentration of Depleted Uranium by its dispersion from soil surface by winds and rains from 2003 to 2007. The exposure rates were measured using inspector device, while depleted uranium concentration in soil samples and tank's matal pieces were detected with Solid State Nuclear Track Detectors(SSNTDs). The wind and rain effects were considered in the calculation of dispersion effect on depleted uranium concentration in soil, where the wind effect were calculated with respect to the sites nature and soil conditions, and rain effect with respect to dispersive-convective equation for radionuclide in soil. The results obtained for the exposure rates were high near the penetrated surfac, moderate and low in soil and metal pices. The Depleted Uranium concentration in soil and metal pieces have the highest value in Nassireya. The results from dispersion calculation (wind & rain) showed that the depleted uranium concentration in 2008 will be less than the danger level and in allowable contamination range

  17. Verification of Depleted Uranium in non-Nuclear use

    International Nuclear Information System (INIS)

    The present work describes a system for the verification of depleted uranium-being recognized by the International Atomic Energy as a Nuclear which should be accounted for and put under Nuclear Safeguards even if it is used for non-nuclear applications such as in shielding against gamma radiation in Radiotherapy facilities, industrial radiography systems or as counterweights in air craft. Measurement of depleted uranium is performed by employing Non-Destructive Assay techniques, which use a gamma-ray spectrometer system and/or a neutron coincidence counter system. Results show that the used techniques can detect the presence of depleted uranium in the investigated materials. Also, quantitative values of U-235 enrichment and mass content of the assayed material could be obtained with a precision of better than 7%. This work would find important applications for the verification and control of depleted uranium for the purposes of Nuclear Safeguards

  18. Importance of energetic solar protons in ozone depletion

    International Nuclear Information System (INIS)

    CHLORINE-catalysed depletion of the stratospheric ozone layer has commanded considerable attention since 1985, when Farman et al. observed a decrease of 50% in the total column ozone over Antarctica in the austral spring. Here we examine the depletion of stratospheric ozone caused by the reaction of ozone with nitric oxide generated by energetic solar protons, associated with solar flares. During large solar flares in March 1989, satellite observations indicated that total column ozone was depleted by ∼ 9% over ∼ 20% of the total area between the South Pole and latitude 70oS. Chlorine-catalysed ozone depletion takes place over a much larger area, but our results indicate that the influence of solar protons on atmospheric ozone concentrations should not be ignored. (author)

  19. Capstone Depleted Uranium Aerosols: Generation and Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Parkhurst, MaryAnn; Szrom, Fran; Guilmette, Ray; Holmes, Tom; Cheng, Yung-Sung; Kenoyer, Judson L.; Collins, John W.; Sanderson, T. Ellory; Fliszar, Richard W.; Gold, Kenneth; Beckman, John C.; Long, Julie

    2004-10-19

    In a study designed to provide an improved scientific basis for assessing possible health effects from inhaling depleted uranium (DU) aerosols, a series of DU penetrators was fired at an Abrams tank and a Bradley fighting vehicle. A robust sampling system was designed to collect aerosols in this difficult environment and continuously monitor the sampler flow rates. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. The resulting data provide input useful in human health risk assessments.

  20. Depleted Uranium Penetrators : Hazards and Safety

    OpenAIRE

    Rao, S S; T. Balakrishna Bhat

    1997-01-01

    The depleted uranium (DU) alloy is a state-of-the-art material for kinetic energy penetrators due to its superior ballistic performance. Several countries use DU penetrators in their main battle tanks. There is no gamma radiation hazard to the crew members from stowage of DO rounds. Open air firing can result in environmental contamination and associated hazards due to airborne particles containing essentially U/sub 3/0/sub 8/ and UO/sub 2/. Inhalation of polluted air only through resp...

  1. Investigation of expression of CFTR and its relationship with apoptosis in lung squamous cell carcinoma%CFTR在肺鳞癌中的表达及其与肿瘤凋亡关系的研究

    Institute of Scientific and Technical Information of China (English)

    李亚秋; 姜文华; 范军达; 郝利铭

    2013-01-01

    Objective To investigate the expression of cystic fibrosis transmembrane conductance regulator (CFTR) to explore its relationship with apoptosis in well and poorly differentiated human lung squamous cell carcinoma.Methods The expression of CFTR was detected by immunohistochemical(S-P) method in 27 lung squamous cell carcinoma tissue,and the apoptosis rate was done by TUNEL method.Results Mean optical density of well-differentiated lung squamous cell carcinoma(1169.22 ± 42.61) was significantly higher than that in poorly differentiated lung squamous cell carcinoma(1047.89 ± 20.62,P<0.05),and the diameter of well-differentiated cancer cells (32.36 ± 1.12) μ m was significantly higher than that of poorly differentiated lung squamous cell carcinoma(21.42 ± 0.97)μm (P<0.01).The apoptosis rate of well-differentiated lung squamous cell carcinoma(12.04 ± 2.36)% was significantly higher than that in poorly differentiated lung squamous cell carcinoma(7.74 ± 1.03)%(P <0.01).The apoptosis rate was positively correlated with the mean optical density of CFTR product in lung squamous carcinoma cells(r=0.619,P<0.01).Conclusion The overexpression of CFTR is positively correlated with the apoptosis of lung squamous cancer cells,indicating that CFTR is related to the promotion of the apoptosis of lung squamous cancer cells.%目的 探讨囊性纤维化跨膜传导调节因子(CFTR)在人高、低分化肺鳞癌组织中的表达,及其与癌细胞凋亡的关系.方法 采用免疫组织化学S-P法检测27例鳞癌组织中CFTR的表达,TUNEL法检测肺鳞癌细胞凋亡率.结果 人高分化鳞癌细胞的CFTR阳性产物平均光密度(1169.22±42.61)显著高于低分化鳞癌的平均光密度(1047.89±20.62,P<0.05),且高分化癌细胞直径(32.36±1.12)μm显著高于低分化癌细胞直径(21.42±0.97)μm(P<0.01).高分化鳞癌组织的凋亡率(12.04±2.36)%显著高于低分化鳞癌组织的凋亡率(7.74±1.03)%(P<0.01).凋亡率与表

  2. The Case of Ozone Depletion

    Science.gov (United States)

    Lambright, W. Henry

    2005-01-01

    While the National Aeronautics and Space Administration (NASA) is widely perceived as a space agency, since its inception NASA has had a mission dedicated to the home planet. Initially, this mission involved using space to better observe and predict weather and to enable worldwide communication. Meteorological and communication satellites showed the value of space for earthly endeavors in the 1960s. In 1972, NASA launched Landsat, and the era of earth-resource monitoring began. At the same time, in the late 1960s and early 1970s, the environmental movement swept throughout the United States and most industrialized countries. The first Earth Day event took place in 1970, and the government generally began to pay much more attention to issues of environmental quality. Mitigating pollution became an overriding objective for many agencies. NASA's existing mission to observe planet Earth was augmented in these years and directed more toward environmental quality. In the 1980s, NASA sought to plan and establish a new environmental effort that eventuated in the 1990s with the Earth Observing System (EOS). The Agency was able to make its initial mark via atmospheric monitoring, specifically ozone depletion. An important policy stimulus in many respects, ozone depletion spawned the Montreal Protocol of 1987 (the most significant international environmental treaty then in existence). It also was an issue critical to NASA's history that served as a bridge linking NASA's weather and land-resource satellites to NASA s concern for the global changes affecting the home planet. Significantly, as a global environmental problem, ozone depletion underscored the importance of NASA's ability to observe Earth from space. Moreover, the NASA management team's ability to apply large-scale research efforts and mobilize the talents of other agencies and the private sector illuminated its role as a lead agency capable of crossing organizational boundaries as well as the science-policy divide.

  3. Benchmark Specification for HTGR Fuel Element Depletion

    International Nuclear Information System (INIS)

    explicitly represent the dynamics of neutron slowing down in a heterogeneous environment with randomised grain distributions, but traditional tracking simulations can be extremely slow, and the large number of grains in a fuel element may often represent an extreme burden on computational resources. A number of approximations or simplifying assumptions have been developed to simplify the computational process and reduce the effort. Multi-group (MG) methods, on the other hand, require special treatment of DH fuels in order to properly capture resonance effects, and generally cannot explicitly represent a random distribution of grains due to the excessive computational burden resulting from the spatial grain distribution. The effect of such approximations may be important and has potential to misrepresent the spectrum within a fuel grain. Depletion methods utilised in lattice calculations typically rely on point depletion methods, based on the isotopic inventory of fuel depleted, assuming a single localised neutron flux. This flux is generally determined using either a CE or MG transport solver. Hence, in application to DH fuels, the primary factor influencing the accuracy of a depletion calculation will be the accuracy of the local flux calculated within the transport solution and the cross-sections. The current lack of well-qualified experimental measurements for spent HGTR fuel elements limits the validation of advanced DH depletion method. Because of this shortage of data, this benchmark has been developed as the first, simplest phase in a planned series of increasingly complex set of code-to-code benchmarks. The intent of this benchmark is to encourage submission of a wide range of computational results for depletion calculations in a set of basic fuel cell models. Comparison of results using independent methods and data should provide insight into potential limitations in various modelling approximations. The benchmark seeks to provide the simplest possible models, in

  4. Uranium, depleted uranium, biological effects

    International Nuclear Information System (INIS)

    Physicists, chemists and biologists at the CEA are developing scientific programs on the properties and uses of ionizing radiation. Since the CEA was created in 1945, a great deal of research has been carried out on the properties of natural, enriched and depleted uranium in cooperation with university laboratories and CNRS. There is a great deal of available data about uranium; thousands of analyses have been published in international reviews over more than 40 years. This presentation on uranium is a very brief summary of all these studies. (author)

  5. Defective fluid secretion from submucosal glands of nasal turbinates from CFTR-/- and CFTR (ΔF508/ΔF508 pigs.

    Directory of Open Access Journals (Sweden)

    Hyung-Ju Cho

    Full Text Available BACKGROUND: Cystic fibrosis (CF, caused by reduced CFTR function, includes severe sinonasal disease which may predispose to lung disease. Newly developed CF pigs provide models to study the onset of CF pathophysiology. We asked if glands from pig nasal turbinates have secretory responses similar to those of tracheal glands and if CF nasal glands show reduced fluid secretion. METHODOLOGY/PRINCIPAL FINDINGS: Unexpectedly, we found that nasal glands differed from tracheal glands in five ways, being smaller, more numerous (density per airway surface area, more sensitive to carbachol, more sensitive to forskolin, and nonresponsive to Substance P (a potent agonist for pig tracheal glands. Nasal gland fluid secretion from newborn piglets (12 CF and 12 controls in response to agonists was measured using digital imaging of mucus bubbles formed under oil. Secretion rates were significantly reduced in all conditions tested. Fluid secretory rates (Controls vs. CF, in pl/min/gland were as follows: 3 µM forskolin: 9.2±2.2 vs. 0.6±0.3; 1 µM carbachol: 143.5±35.5 vs. 52.2±10.3; 3 µM forskolin + 0.1 µM carbachol: 25.8±5.8 vs. CF 4.5±0.9. We also compared CF(ΔF508/ΔF508 with CFTR(-/- piglets and found significantly greater forskolin-stimulated secretion rates in the ΔF508 vs. the null piglets (1.4±0.8, n = 4 vs. 0.2±0.1, n = 7. An unexpected age effect was also discovered: the ratio of secretion to 3 µM forskolin vs. 1 µM carbachol was ∼4 times greater in adult than in neonatal nasal glands. CONCLUSIONS/SIGNIFICANCE: These findings reveal differences between nasal and tracheal glands, show defective fluid secretion in nasal glands of CF pigs, reveal some spared function in the ΔF508 vs. null piglets, and show unexpected age-dependent differences. Reduced nasal gland fluid secretion may predispose to sinonasal and lung infections.

  6. A modern depleted uranium manufacturing facility

    International Nuclear Information System (INIS)

    The Specific Manufacturing Capabilities (SMC) Project located at the Idaho National Engineering Laboratory (INEL) and operated by Lockheed Martin Idaho Technologies Co. (LMIT) for the Department of Energy (DOE) manufactures depleted uranium for use in the U.S. Army MIA2 Abrams Heavy Tank Armor Program. Since 1986, SMC has fabricated more than 12 million pounds of depleted uranium (DU) products in a multitude of shapes and sizes with varying metallurgical properties while maintaining security, environmental, health and safety requirements. During initial facility design in the early 1980's, emphasis on employee safety, radiation control and environmental consciousness was gaining momentum throughout the DOE complex. This fact coupled with security and production requirements forced design efforts to focus on incorporating automation, local containment and computerized material accountability at all work stations. The result was a fully automated production facility engineered to manufacture DU armor packages with virtually no human contact while maintaining security, traceability and quality requirements. This hands off approach to handling depleted uranium resulted in minimal radiation exposures and employee injuries. Construction of the manufacturing facility was complete in early 1986 with the first armor package certified in October 1986. Rolling facility construction was completed in 1987 with the first certified plate produced in the fall of 1988. Since 1988 the rolling and manufacturing facilities have delivered more than 2600 armor packages on schedule with 100% final product quality acceptance. During this period there was an annual average of only 2.2 lost time incidents and a single individual maximum radiation exposure of 150 mrem. SMC is an example of designing and operating a facility that meets regulatory requirements with respect to national security, radiation control and personnel safety while achieving production schedules and product quality

  7. A modern depleted uranium manufacturing facility

    Energy Technology Data Exchange (ETDEWEB)

    Zagula, T.A.

    1995-07-01

    The Specific Manufacturing Capabilities (SMC) Project located at the Idaho National Engineering Laboratory (INEL) and operated by Lockheed Martin Idaho Technologies Co. (LMIT) for the Department of Energy (DOE) manufactures depleted uranium for use in the U.S. Army MIA2 Abrams Heavy Tank Armor Program. Since 1986, SMC has fabricated more than 12 million pounds of depleted uranium (DU) products in a multitude of shapes and sizes with varying metallurgical properties while maintaining security, environmental, health and safety requirements. During initial facility design in the early 1980`s, emphasis on employee safety, radiation control and environmental consciousness was gaining momentum throughout the DOE complex. This fact coupled with security and production requirements forced design efforts to focus on incorporating automation, local containment and computerized material accountability at all work stations. The result was a fully automated production facility engineered to manufacture DU armor packages with virtually no human contact while maintaining security, traceability and quality requirements. This hands off approach to handling depleted uranium resulted in minimal radiation exposures and employee injuries. Construction of the manufacturing facility was complete in early 1986 with the first armor package certified in October 1986. Rolling facility construction was completed in 1987 with the first certified plate produced in the fall of 1988. Since 1988 the rolling and manufacturing facilities have delivered more than 2600 armor packages on schedule with 100% final product quality acceptance. During this period there was an annual average of only 2.2 lost time incidents and a single individual maximum radiation exposure of 150 mrem. SMC is an example of designing and operating a facility that meets regulatory requirements with respect to national security, radiation control and personnel safety while achieving production schedules and product quality.

  8. "When the going gets tough, who keeps going?" : Depletion sensitivity moderates the ego-depletion effect

    NARCIS (Netherlands)

    Salmon, Stefanie J.; Adriaanse, Marieke A.; De Vet, Emely; Fennis, Bob M.; De Ridder, Denise T. D.

    2014-01-01

    Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In thre

  9. Expandiendo el espectro mutacional en pacientes chilenos con fibrosis quística Expanding the CFTR mutation spectrum in Chilean patients with cystic fibrosis

    Directory of Open Access Journals (Sweden)

    Marcos Vásquez D

    2012-06-01

    -9000 newborns in Chile. More than 1,800 different mutations have been identified in CFTR gene. The available molecular diagnosis analyzes the 36 most frequent mutations in Caucasian population, with an overall detection rate of80-85%, but with a much lower detection rate in Chilean patients of 42%. To analyze which other mutations are present in Chilean patients, we conducted an extensive analysis by direct DNA sequencing of coding sequences of the CFTR gene. Methods: Forty eight Chilean patients with clinical diagnosis of CF and one mutated allele in the CFTR gene identified, were studied by direct sequence analysis of exons 6, 7, 14, 19 and 20 of the CFTR gene. Results: We found 3 different mutations in 14 cases that had not been previously identified in Chilean patients. Four patients have a deletion of two nucleotides (c.2462_2463delGT/p.Ser821ArgfsX4 in exon 14, which is predicted to cause a frameshift and a premature stop codon. Eight patients have c.3196C>T mutation in the exon 20 and 2 cases has c.3039delC mutation in the exon 19. Both mutations had been previously described in other populations. Discussion: The identification of these mutations has notably increased the detection rate in our patients. Adapting the molecular diagnosis method by including these three mutations should increase the CF detection rate in Chilean patients. This analysis will improve CF diagnosis and allow an adequate genetic counseling to the families.

  10. Biomedical consequences of ozone depletion

    Science.gov (United States)

    Coohill, Thomas P.

    1994-07-01

    It is widely agreed that a portion of the earth's protective stratospheric ozone layer is being depleted. The major effect of this ozone loss will be an increase in the amount of ultraviolet radiation (UV reaching the biosphere. This increase will be completely contained within the UVB (290nm - 320nm). It is imperative that assessments be made of the effects of this additional UVB on living organisms. This requires a detailed knowledge of the UVB photobiology of these life forms. One analytical technique to aid in the approximations is the construction of UV action spectra for such important biological end-points as human skin cancer, cataracts, immune suppression; plant photosynthesis and crop yields; and aquatic organism responses to UVB, especially the phytoplankton. Combining these action spectra with the known solar spectrum (and estimates for various ozone depletion scenarios) can give rise to a series of effectiveness spectra for these parameters. This manuscript gives a first approximation, rough estimate, for the effectiveness spectra for some of these bioresponses, and a series of crude temporary values for how a 10% ozone loss would affect the above end-points. These are not intended to masquerade as final answers, but rather, to serve as beginning attempts for a process which should be continually refined. It is hoped that these estimates will be of some limited use to agencies, such as government and industry, that have to plan now for changes in human activities that might alter future atmospheric chemistry in a beneficial manner.

  11. Clusters of Cl- channels in CFTR-expressing Sf9 cells switch spontaneously between slow and fast gating modes

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Price, E. M.; Gabriel, S. E.;

    1996-01-01

    The Sf9 insect Spodoptora frugiperda cell line was used for heterologous expression of the cloned human cystic fibrosis transmembrane conductance regulator (CFTR) cDNA, or the cloned ß-galactosidase gene, using the baculovirus Autographa califonica as the infection vector. Using application of the...... patch-clamp technique, evidence for functional expression of CFTR was obtained according to the following three criteria. Firstly, whole-cell currents recorded 2 days after infection with CFTR revealed a statistically significant increase of membrane conductance, ˜25 times above that of mock......-infected control cells, with the reversal potential of the major current component being governed by the chloride equilibrium potential (E Cl). Secondly, in contrast to uninfected cells and cells infected with ß-galactosidase, the membrane conductance to chloride of CFTR-injected cells was stimulated by cytosolic...

  12. Purinergic regulation of CFTR and Ca2+ -activated Cl- channels and K+ channels in human pancreatic duct epithelium

    DEFF Research Database (Denmark)

    Wang, Jing; Haanes, Kristian A; Novak, Ivana

    2013-01-01

    dependent on intracellular Ca(2+). Apically applied ATP/UTP stimulated CF transmembrane conductance regulator (CFTR) and Ca(2+)-activated Cl(-) (CaCC) channels, which were inhibited by CFTRinh-172 and niflumic acid, respectively. The basolaterally applied ATP stimulated CFTR. In CFPAC-1 cells, which have...... mutated CFTR, basolateral ATP and UTP had negligible effects. In addition to Cl(-) transport in Capan-1 cells, the effects of 5,6-dichloro-1-ethyl-1,3-dihydro-2H-benzimidazol-2-one (DC-EBIO) and clotrimazole indicated functional expression of the intermediate conductance K(+) channels (IK, KCa3.1). The...... receptors both Cl(-) channels (TMEM16A/ANO1 and CFTR) and K(+) channels (IK). The K(+) channels provide the driving force for Cl(-)-channel-dependent secretion, and luminal ATP provided locally or secreted from acini may potentiate secretory processes. Future strategies in augmenting pancreatic duct...

  13. The 1988 Antarctic ozone depletion - Comparison with previous year depletions

    Science.gov (United States)

    Schoeberl, Mark R.; Stolarski, Richard S.; Krueger, Arlin J.

    1989-01-01

    The 1988 spring Antarctic ozone depletion was observed by TOMS to be substantially smaller than in recent years. The minimum polar total ozone values declined only 15 percent during September 1988, compared to nearly 50 percent during September 1987. At southern midlatitudes, exceptionally high total ozone values were recorded beginning in July 1988. The total integrated southern hemispheric ozone increased rapidly during the Austral spring, approaching 1980 levels during October. The high midlatitude total ozone values were associated with a substantial increase in eddy activity as indicated by the standard deviation in total ozone in the zonal band 30-60 deg S. Mechanisms through which the increased midlatitude eddy activity could disrupt the formation of the Antarctic ozone hole are briefly discussed.

  14. Measurements of CFTR-Mediated Cl− Secretion in Human Rectal Biopsies Constitute a Robust Biomarker for Cystic Fibrosis Diagnosis and Prognosis

    OpenAIRE

    Sousa, Marisa; Servidoni, Maria F; Vinagre, Adriana M.; Ramalho, Anabela S; Bonadia, Luciana C.; Felício, Verónica; Ribeiro, Maria A..; Uliyakina, Inna; Marson A, Fernando; Kmit, Arthur; Cardoso, Silvia R.; Ribeiro, José D; Carmen S. Bertuzzo; Sousa, Lisete; Kunzelmann, Karl

    2012-01-01

    BACKGROUND: Cystic Fibrosis (CF) is caused by ∼1,900 mutations in the CF transmembrane conductance regulator (CFTR) gene encoding for a cAMP-regulated chloride (Cl(-)) channel expressed in several epithelia. Clinical features are dominated by respiratory symptoms, but there is variable organ involvement thus causing diagnostic dilemmas, especially for non-classic cases. METHODOLOGY/PRINCIPAL FINDINGS: To further establish measurement of CFTR function as a sensitive and robust biomarker fo...

  15. Restoration of R117H CFTR folding and function in human airway cells through combination treatment with VX-809 and VX-770.

    Science.gov (United States)

    Gentzsch, Martina; Ren, Hong Y; Houck, Scott A; Quinney, Nancy L; Cholon, Deborah M; Sopha, Pattarawut; Chaudhry, Imron G; Das, Jhuma; Dokholyan, Nikolay V; Randell, Scott H; Cyr, Douglas M

    2016-09-01

    Cystic fibrosis (CF) is a lethal recessive genetic disease caused primarily by the F508del mutation in the CF transmembrane conductance regulator (CFTR). The potentiator VX-770 was the first CFTR modulator approved by the FDA for treatment of CF patients with the gating mutation G551D. Orkambi is a drug containing VX-770 and corrector VX809 and is approved for treatment of CF patients homozygous for F508del, which has folding and gating defects. At least 30% of CF patients are heterozygous for the F508del mutation with the other allele encoding for one of many different rare CFTR mutations. Treatment of heterozygous F508del patients with VX-809 and VX-770 has had limited success, so it is important to identify heterozygous patients that respond to CFTR modulator therapy. R117H is a more prevalent rare mutation found in over 2,000 CF patients. In this study we investigated the effectiveness of VX-809/VX-770 therapy on restoring CFTR function in human bronchial epithelial (HBE) cells from R117H/F508del CF patients. We found that VX-809 stimulated more CFTR activity in R117H/F508del HBEs than in F508del/F508del HBEs. R117H expressed exclusively in immortalized HBEs exhibited a folding defect, was retained in the ER, and degraded prematurely. VX-809 corrected the R117H folding defect and restored channel function. Because R117 is involved in ion conductance, VX-770 acted additively with VX-809 to restore CFTR function in chronically treated R117H/F508del cells. Although treatment of R117H patients with VX-770 has been approved, our studies indicate that Orkambi may be more beneficial for rescue of CFTR function in these patients. PMID:27402691

  16. Involvement of F1296 and N1303 of CFTR in induced-fit conformational change in response to ATP binding at NBD2

    OpenAIRE

    Szollosi, A; P.; Vergani; Csanady, L.

    2010-01-01

    The chloride ion channel cystic fibrosis transmembrane conductance regulator (CFTR) displays a typical adenosine trisphosphate (ATP)-binding cassette (ABC) protein architecture comprising two transmembrane domains, two intracellular nucleotide-binding domains (NBDs), and a unique intracellular regulatory domain. Once phosphorylated in the regulatory domain, CFTR channels can open and close when supplied with cytosolic ATP. Despite the general agreement that formation of a head-to-tail NBD dim...

  17. Equatorial airglow depletions induced by thermospheric winds

    Energy Technology Data Exchange (ETDEWEB)

    Meriwether J.W. Jr.; Biondi, M.A.; Anderson, D.N.

    1985-08-01

    Interferometric observations of the 630.0 nm nightglow brightness at the equatorial station of Arequipa. Peru (16.2/sup 0/S, 71.4/sup 0/W geographic, 3.2/sup 0/S dip latitude) have revealed widespread areas of airglow depletion, with reductions in intensity as large as factors of 3 or 4. These depletions correlated closely with large increases of the equatorward (northward) wind and the 630.0 nm kinetic temperature. On occasion, the usually small meridonal wind reached a velocity of 100 m/s near 22/sup h/ LT lasting for 1 or 2 hours. The temperature increases of 10 K or more existed only in the poleward (southward) direction. Comparisons with modeling calculations suggest that this effect results from an upward movement of the ionosphere along the inclined magnetic field lines, driven by the equatorward neutral wind. The airglow column integrated emission rate is consequently decreased by the slower rate of formation and subsequent dissociative recombination of molecular oxygen ions within the higher F-layer. We conclude that the transient period of equatorward wind is a result of the passage of the midnight pressure bulge.

  18. Equatorial airglow depletions induced by thermospheric winds

    Energy Technology Data Exchange (ETDEWEB)

    Meriwether, J.W.; Biondi, M.A.; Anderson, D.N.

    1985-08-01

    Interferometric observations on the 630.0 nm nightglow brightness at the equatorial station at Arequipa, Peru (16.2 S, 71.4 W geographic, 3.2 S dip latitude) have revealed widespread areas of airglow depletion, with reductions in intensity as large as factors of 3 or 4. These depletions correlated closely with large increases of the equatorward (northward) wind and the 630.0 nm kinetic temperature. On occasion, the usually small meridional wind reached a velocity of 100 m/s near 22h LT lasting for 1 to 2 hours. The temperature increases of 100K or more existed only in the poleware (southward) direction. Comparisons with modeling calculations suggest that this effect results from an upward movement of the ionosphere along the inclined magnetic field lines, driven by the equatorward neutral wind. The airglow column integrated emission rate is consequently decreased by the slower rate of formation and subsequent dissociative recombination of molecular oxygen ions within the higher F-layer. We conclude that the transient period of equatorward wind is a result of the passage of the midnight pressure bulge. (Author)

  19. Molecular beam depletion: a new approach

    CERN Document Server

    Dorado, Manuel

    2014-01-01

    During the last years some interesting experimental results have been reported for experiments in N20, N0 , N0 dimer , H2 , Toluene and BaFCH3 cluster. The main result consists in the observation of molecular beam depletion when the molecules of a pulsed beam interact with a static electric or magnetic field and an oscillating field (RF). In these cases, and as a main difference, instead of using four fields as in the original technique developed by I.I. Rabi and others, only two fields, those which configure the resonant unit, are used. That is, without using the nonhomogeneous magnetic fields. The depletion explanation for I.I. Rabi and others is based in the interaction between the molecular electric or magnetic dipole moment and the non-homogeneous fields. But, obviously, the change in the molecules trajectories observed on these new experiments has to be explained without considering the force provided by the field gradient because it happens without using non-homogeneous fields. In this paper a theoreti...

  20. Detection of the mutation of all the exons of the CFTR gene in Chinese men with congenital bilateral absence of the vas deferens%中国先天性双侧输精管缺如患者CFTR基因全部外显子突变检测

    Institute of Scientific and Technical Information of China (English)

    杜强; 方媛媛; 潘永峰; 潘伯臣; 宋永胜; 吴斌

    2012-01-01

    目的:探讨我国先天性双侧输精管缺如患者CFTR基因检测的必要性. 方法:采用PCR技术结合DNA直接测序的方法检测9例先天性双侧输精管缺如患者CFTR基因全部外显子的突变情况,并在NCBI和Cystic Fibrosis Mutation Database在线比对. 结果:除非编码区突变和已经报道的SNP位点之外,9例先天性双侧输精管缺如患者中4例新发现4种不同于西方人已知突变类型的外显子区突变,均为杂合子错义突变. 结论:中国先天性双侧输精管缺如患者CFTR基因外显子区存在不同于西方人的突变,有必要对中国先天性双侧输精管缺如患者进行CFTR基因突变检测.%To assess the necessity of detecting the gene of cystic fibrosis transmembrane conductance regulator factor ( CFTR) in Chinese men with congenital bilateral absence of the vas deferens (CBAVD). Methods : We detected the mutation of all the 27 exons of the CFTR gene in 9 patients with CBAVD by DNA sequencing, and compared the results using NCBI and Cystic Fibrosis Mutation Database. Results: Four novel missense mutations / variants were found in the CFTR gene of the CBAVD patients, which were submitted and accepted in the Cystic Fibrosis Mutation Database. Conclusion: There are mutations or variants in the CFTR gene in Chinese men with CBAVD, and the mutational distribution is different from that in Westerners.

  1. Regret causes ego-depletion and finding benefits in the regrettable events alleviates ego-depletion.

    Science.gov (United States)

    Gao, Hongmei; Zhang, Yan; Wang, Fang; Xu, Yan; Hong, Ying-Yi; Jiang, Jiang

    2014-01-01

    This study tested the hypotheses that experiencing regret would result in ego-depletion, while finding benefits (i.e., "silver linings") in the regret-eliciting events counteracted the ego-depletion effect. Using a modified gambling paradigm (Experiments 1, 2, and 4) and a retrospective method (Experiments 3 and 5), five experiments were conducted to induce regret. Results revealed that experiencing regret undermined performance on subsequent tasks, including a paper-and-pencil calculation task (Experiment 1), a Stroop task (Experiment 2), and a mental arithmetic task (Experiment 3). Furthermore, finding benefits in the regret-eliciting events improved subsequent performance (Experiments 4 and 5), and this improvement was mediated by participants' perceived vitality (Experiment 4). This study extended the depletion model of self-regulation by considering emotions with self-conscious components (in our case, regret). Moreover, it provided a comprehensive understanding of how people felt and performed after experiencing regret and after finding benefits in the events that caused the regret. PMID:24940811

  2. Depleted Argon from Underground Sources

    International Nuclear Information System (INIS)

    Argon is a strong scintillator and an ideal target for Dark Matter detection; however 39Ar contamination in atmospheric argon from cosmic ray interactions limits the size of liquid argon dark matter detectors due to pile-up. Argon from deep underground is depleted in 39Ar due to the cosmic ray shielding of the earth. In Cortez, Colorado, a CO2 well has been discovered to contain approximately 600 ppm of argon as a contamination in the CO2. We first concentrate the argon locally to 3% in an Ar, N2, and He mixture, from the CO2 through chromatographic gas separation, and then the N2 and He will be removed by continuous distillation to purify the argon. We have collected 26 kg of argon from the CO2 facility and a cryogenic distillation column is under construction at Fermilab to further purify the argon.

  3. Depleted uranium disposal options evaluation

    International Nuclear Information System (INIS)

    The Department of Energy (DOE), Office of Environmental Restoration and Waste Management, has chartered a study to evaluate alternative management strategies for depleted uranium (DU) currently stored throughout the DOE complex. Historically, DU has been maintained as a strategic resource because of uses for DU metal and potential uses for further enrichment or for uranium oxide as breeder reactor blanket fuel. This study has focused on evaluating the disposal options for DU if it were considered a waste. This report is in no way declaring these DU reserves a ''waste,'' but is intended to provide baseline data for comparison with other management options for use of DU. To PICS considered in this report include: Retrievable disposal; permanent disposal; health hazards; radiation toxicity and chemical toxicity

  4. Depleted uranium. Nuclear related problems

    International Nuclear Information System (INIS)

    Depleted uranium (DU) has found a military application in Golf War, in Bosnia and in Yugoslavia (Kosovo). In military sense it was very efficient. But the fact that some parts of that ammunition are manufactured from depleted uranium, low level radioactive waste, implies other aspects of this application like radiological, ecological, jurist, ethical and psychological. The subject of this paper is just physical aspect. There are several problems concerning this aspect: production of DU, total amount of DU in the world, 235U/238U relation, radioactivity of DU, measurements, and presence of other radionuclides like plutonium. DU is by product of nuclear technology and represents low-level nuclear waste. Therefore it should be stored. Total amount of DU in the world is about one million tons with an annual increase of 30 000 t. The content of 235U in DU can vary in the range 0.16-0.3%. The total radioactivity of DU is a consequence of 7 radionuclides and amounts 39.42 Bq/mg. This include alpha, beta and gamma radioactivity. Because of characteristics of this radioactivity it is difficult to prospect the terrain except at the site of action. During the impact of DU rods four types of DU particles could be produced: whole penetrators, penetrator parts, big aerosols (>10 μm) and small aerosols (<10 μm). Most of these particles fall locally, although some of them could be find several tens of kilometers away. All these problems have been discussed in this paper. (author)

  5. Thermal unfolding studies show the disease causing F508del mutation in CFTR thermodynamically destabilizes nucleotide-binding domain 1.

    Science.gov (United States)

    Protasevich, Irina; Yang, Zhengrong; Wang, Chi; Atwell, Shane; Zhao, Xun; Emtage, Spencer; Wetmore, Diana; Hunt, John F; Brouillette, Christie G

    2010-10-01

    Misfolding and degradation of CFTR is the cause of disease in patients with the most prevalent CFTR mutation, an in-frame deletion of phenylalanine (F508del), located in the first nucleotide-binding domain of human CFTR (hNBD1). Studies of (F508del)CFTR cellular folding suggest that both intra- and inter-domain folding is impaired. (F508del)CFTR is a temperature-sensitive mutant, that is, lowering growth temperature, improves both export, and plasma membrane residence times. Yet, paradoxically, F508del does not alter the fold of isolated hNBD1 nor did it seem to perturb its unfolding transition in previous isothermal chemical denaturation studies. We therefore studied the in vitro thermal unfolding of matched hNBD1 constructs ±F508del to shed light on the defective folding mechanism and the basis for the thermal instability of (F508del)CFTR. Using primarily differential scanning calorimetry (DSC) and circular dichroism, we show for all hNBD1 pairs studied, that F508del lowers the unfolding transition temperature (T(m)) by 6-7°C and that unfolding occurs via a kinetically-controlled, irreversible transition in isolated monomers. A thermal unfolding mechanism is derived from nonlinear least squares fitting of comprehensive DSC data sets. All data are consistent with a simple three-state thermal unfolding mechanism for hNBD1 ± F508del: N(±MgATP) I(T)(±MgATP) → A(T) → (A(T))(n). The equilibrium unfolding to intermediate, I(T), is followed by the rate-determining, irreversible formation of a partially folded, aggregation-prone, monomeric state, A(T), for which aggregation to (A(T))(n) and further unfolding occur with no detectable heat change. Fitted parameters indicate that F508del thermodynamically destabilizes the native state, N, and accelerates the formation of A(T). PMID:20687133

  6. Diagnostic value of guided fine needle aspiration accompanied by CFTR detection in chronic pancreatitis%内镜超声引导下穿刺联合CFTR基因检测对慢性胰腺炎的诊断价值

    Institute of Scientific and Technical Information of China (English)

    郑著家; 李长福; 韩继武

    2011-01-01

    Objective To evaluate significance of diagnosis with endoscopic ultrasonography guided fine needle aspiration (EUS-FNA) accompanied by cystic fibrosis transmembrane conductance regulator (CFTR) detection in chronic pancreatitis. Methods Endoscopic ultrasonography guided fine needle aspiration was performed in 120 patients with chronic pancreatitis at our hospital and the Fourth Affiliated Hospital of Harbin Medical University from August 2003 to December 2005. At the same time. CFR was detected. Results In EUS-FNA specimens of patients, the contents of CFTR were significantly higher than that in blood ( P < 0. 05 ), 20% of the patients were dignosed as pancreatic cancer. Conclusion EUS-FNA accompanied by CFTR detection is important in diagnosis of chronic pancreatitis.%目的 探讨内镜超声引导下细针穿刺活检(endoscopic ultrasonography guided fine needle aspiration,EUS-FNA )联合囊性纤维化转膜传导调节因子(cystic fibrosis transmembrane conductance regulator,CFTR)基因检测对慢性胰腺炎的诊断价值.方法 对本院及哈尔滨医科大学附属第四医院120例慢性胰腺炎患者进行超声内镜引导下穿刺活检,并采用免疫印迹方法检测CFTR基因表达情况.结果 活检物中的CFTR检测阳性率明显高于血清中的浓度,其中小胰腺癌检出率为20%.结论 EUS-FNA联合CFTR基因检测对慢性胰腺炎的诊断具有重要价值.

  7. The Influence of Chronic Ego Depletion on Goal Adherence: An Experience Sampling Study.

    Directory of Open Access Journals (Sweden)

    Ligang Wang

    Full Text Available Although ego depletion effects have been widely observed in experiments in which participants perform consecutive self-control tasks, the process of ego depletion remains poorly understood. Using the strength model of self-control, we hypothesized that chronic ego depletion adversely affects goal adherence and that mental effort and motivation are involved in the process of ego depletion. In this study, 203 students reported their daily performance, mental effort, and motivation with respect to goal directed behavior across a 3-week time period. People with high levels of chronic ego depletion were less successful in goal adherence than those with less chronic ego depletion. Although daily effort devoted to goal adherence increased with chronic ego depletion, motivation to adhere to goals was not affected. Participants with high levels of chronic ego depletion showed a stronger positive association between mental effort and performance, but chronic ego depletion did not play a regulatory role in the effect of motivation on performance. Chronic ego depletion increased the likelihood of behavior regulation failure, suggesting that it is difficult for people in an ego-depletion state to adhere to goals. We integrate our results with the findings of previous studies and discuss possible theoretical implications.

  8. Halocarbon ozone depletion and global warming potentials

    Science.gov (United States)

    Cox, Richard A.; Wuebbles, D.; Atkinson, R.; Connell, Peter S.; Dorn, H. P.; Derudder, A.; Derwent, Richard G.; Fehsenfeld, F. C.; Fisher, D.; Isaksen, Ivar S. A.

    1990-01-01

    Concern over the global environmental consequences of fully halogenated chlorofluorocarbons (CFCs) has created a need to determine the potential impacts of other halogenated organic compounds on stratospheric ozone and climate. The CFCs, which do not contain an H atom, are not oxidized or photolyzed in the troposphere. These compounds are transported into the stratosphere where they decompose and can lead to chlorine catalyzed ozone depletion. The hydrochlorofluorocarbons (HCFCs or HFCs), in particular those proposed as substitutes for CFCs, contain at least one hydrogen atom in the molecule, which confers on these compounds a much greater sensitivity toward oxidation by hydroxyl radicals in the troposphere, resulting in much shorter atmospheric lifetimes than CFCs, and consequently lower potential for depleting ozone. The available information is reviewed which relates to the lifetime of these compounds (HCFCs and HFCs) in the troposphere, and up-to-date assessments are reported of the potential relative effects of CFCs, HCFCs, HFCs, and halons on stratospheric ozone and global climate (through 'greenhouse' global warming).

  9. Repulsive depletion interactions in colloid polymer mixtures

    OpenAIRE

    Rudhardt, Daniel; Bechinger, Clemens; Leiderer, Paul

    1999-01-01

    Depletion forces in colloidal systems are known to be entirely attractive, as long as the background of macromolecules is small enough that an ideal gas approach is valid. At higher densities, however, structural correlation effects of the macromolecules which lead to additional repulsive parts in the depletion interaction, have to be taken into account. We have measured the depletion interaction between a single polystyrene sphere and a wall in the presence of non-ionic polymer coils. Althou...

  10. Treatment with depleting CD4 monoclonal antibody results in a preferential loss of circulating naive T cells but does not affect IFN-gamma secreting TH1 cells in humans

    OpenAIRE

    Rep, M.H.G.; Oosten, van, J.M.F.; Roos, M T; Adér, H.J.; Polman, C H; Lier, van, R.

    1997-01-01

    CD4(pos) TH1 T cells are considered to play a central role in a number of human autoimmune diseases such as rheumatoid arthritis (RA) and multiple sclerosis. Experimental treatment protocols aimed at selectively eliminating CD4(pos) T cells thus far have yielded disappointing clinical results. Here we analyzed phenotype and function of circulating T cells in multiple sclerosis patients treated with the chimeric CD4 mAb cM-T412 in a randomized, double-blind, placebo-controlled, magnetic resona...

  11. EFFECTS OF MONOCARBOXYLIC ACID DERIVATIVES ON CARDIAC VENTRICULAR CFTR Cl-CHANNELS IN GUINEA PIG%单羧酸类Cl-通道阻断剂对心室肌CFTR Cl-通道的影响

    Institute of Scientific and Technical Information of China (English)

    周士胜; 臧益民

    1999-01-01

    本文采用全细胞膜片箝与细胞内灌注技术,观察了单羧酸类 Cl-通道阻断剂对豚鼠心室肌囊性纤维变性膜透性调节蛋白(CFTR)Cl-电流的影响,细胞外9-AC以可逆方式增强异丙肾上腺素(ISO)激发的CFTR Cl-的外向电流成分,5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB)和二苯胺羧酸(DPC)对ISO发的CFTR Cl-电流的作用呈现先增强后抑制的双相效应.细胞内NPPB表现为增强ISO激发作用.结果表明,单羧酸类Cl-通道阻断剂在细胞上有不同的作用位点,该类药物作用效果的差异可能与此有关.

  12. Endocytic Sorting of CFTR variants Monitored by Single Cell Fluorescence Ratio Image Analysis (FRIA) in Living Cells

    Science.gov (United States)

    Barriere, H.; Apaja, P.; Okiyoneda, T.; Lukacs, G. L.

    2016-01-01

    Summary The wild-type CFTR channel undergoes constitutive internalization and recycling at the plasma membrane. This process is initiated by the recognition of the Tyr- and di-Leu-based endocytic motifs of CFTR by the AP-2 adaptor complex, leading to the formation of clathrin-coated vesicles and the channel delivery to sorting/recycling endosomes. Accumulating evidence suggests that conformationally defective mutant CFTRs (e.g. rescued ΔF508 and glycosylation-deficient channel) are unstable at the plasma membrane and undergo augmented ubiquitination in post-Golgi compartments. Ubiquitination conceivably accounts for the metabolic instability at cell surface by provoking accelerated internalization, as well as rerouting the channel from recycling towards lysosomal degradation. We developed an in vivo fluorescence ratio imaging assay (FRIA) that in concert with genetic manipulation can be utilized to establish the post-endocytic fate and sorting determinants of mutant CFTRs. PMID:21594793

  13. Resource depletion does not influence prospective memory in college students.

    Science.gov (United States)

    Shelton, Jill Talley; Cahill, Michael J; Mullet, Hillary G; Scullin, Michael K; Einstein, Gilles O; McDaniel, Mark A

    2013-12-01

    This paper reports an experiment designed to investigate the potential influence of prior acts of self-control on subsequent prospective memory performance. College undergraduates (n=146) performed either a cognitively depleting initial task (e.g., mostly incongruent Stroop task) or a less resource-consuming version of that task (e.g., all congruent Stroop task). Subsequently, participants completed a prospective memory task that required attentionally demanding monitoring processes. The results demonstrated that prior acts of self-control do not impair the ability to execute a future intention in college-aged adults. We conceptually replicated these results in three additional depletion and prospective memory experiments. This research extends a growing number of studies demonstrating the boundary conditions of the resource depletion effect in cognitive tasks. PMID:24021851

  14. Analysis of the CFTR gene in Venezuelan cystic fibrosis patients, identification of six novel cystic fibrosis-causing genetic variants

    OpenAIRE

    Sánchez K; de Mendonca E; Matute X; Chaustre I; Villalón M; Takiff H

    2016-01-01

    Karen Sánchez,1 Elizabeth de Mendonca,1 Xiorama Matute,2 Ismenia Chaustre,2 Marlene Villalón,3 Howard Takiff4 1Unit of Genetic and Forensic Studies, Venezuelan Institute for Scientific Research (IVIC), 2Hospital JM de los Ríos, 3Hospital José Ignacio Baldo, Algodonal, National Reference Unit, 4Laboratory of Molecular Genetics, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela. Abstract: The mutations in the CFTR gene found in patients with cy...

  15. Analysis of the CFTR gene in Venezuelan cystic fibrosis patients, identification of six novel cystic fibrosis-causing genetic variants

    OpenAIRE

    Sánchez, Karen

    2016-01-01

    Karen Sánchez,1 Elizabeth de Mendonca,1 Xiorama Matute,2 Ismenia Chaustre,2 Marlene Villalón,3 Howard Takiff4 1Unit of Genetic and Forensic Studies, Venezuelan Institute for Scientific Research (IVIC), 2Hospital JM de los Ríos, 3Hospital José Ignacio Baldo, Algodonal, National Reference Unit, 4Laboratory of Molecular Genetics, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela. Abstract: The mutations in the CFTR gene found in ...

  16. Frequency of CFTR, SPINK1, and Cathepsin B Gene Mutation in North Indian Population: Connections between Genetics and Clinical Data

    OpenAIRE

    Shweta Singh; Gourdas Choudhuri; Sarita Agarwal

    2014-01-01

    Objectives. Genetic mutations and polymorphisms have been correlated with chronic pancreatitis (CP). This study aims to investigate the association of genetic variants of cystic fibrosis transmembrane conductance regulator (CFTR) and serine protease inhibitor Kazal type 1 (SPINK-1) genes and Cathepsin B gene polymorphisms with CP and to associate genetic backgrounds with clinical phenotypes. Methods. 150 CP patients and 150 normal controls were enrolled consecutively. We analyzed SPINK-1 N34S...

  17. Detection of Five Common CFTR Mutations by Rapid-Cycle Real-Time Amplification Refractory Mutation System PCR

    OpenAIRE

    Dempsey, Eugene; Barton, Davis; Ryan, Fergus X.

    2004-01-01

    Cystic fibrosis is the most common autosomal recessive disease in Caucasian populations and has a carrier frequency of 1 in 25 (1 ). The gene involved codes for the cystic fibrosis transmembrane conductance regulator (CFTR), a membrane-associated protein involved in ion transport across the plasma membrane of epithelial cells. To date more than 1000 mutations have been described in this gene, and most are rare (2 ). By focusing on five common mutations it is possible to detect the diseasecaus...

  18. Beneficial Uses of Depleted Uranium

    International Nuclear Information System (INIS)

    Naturally occurring uranium contains 0.71 wt% 235U. In order for the uranium to be useful in most fission reactors, it must be enriched the concentration of the fissile isotope 235U must be increased. Depleted uranium (DU) is a co-product of the processing of natural uranium to produce enriched uranium, and DU has a 235U concentration of less than 0.71 wt%. In the United States, essentially all of the DU inventory is in the chemical form of uranium hexafluoride (UF6) and is stored in large cylinders above ground. If this co-product material were to be declared surplus, converted to a stable oxide form, and disposed, the costs are estimated to be several billion dollars. Only small amounts of DU have at this time been beneficially reused. The U.S. Department of Energy (DOE) has begun the Beneficial Uses of DU Project to identify large-scale uses of DU and encourage its reuse for the primary purpose of potentially reducing the cost and expediting the disposition of the DU inventory. This paper discusses the inventory of DU and its rate of increase; DU disposition options; beneficial use options; a preliminary cost analysis; and major technical, institutional, and regulatory issues to be resolved

  19. Ozone depletion potentials of halocarbons

    International Nuclear Information System (INIS)

    The concept of ozone depletion potential (ODP) is widely used in the evaluation of numerous halocarbons and of their replacements for effects on ozone, but the methods, model assumptions and conditions of ODP calculation have not been analyzed adequately. In this paper, a model study of effects on ozone after the instantaneous releases of various amounts of CH3CCl3 and of CHF2Cl(HCFC-22) in the several conditions of the background atmosphere are presented, aimed to understand the main connections of ODP values with the methods of their calculations. To facilitate the ODP computation in numerous versions for long after the releases, the above rather short-lived gases have been used. The variation of released gas global mass from 1 Mt to 1 Gt leads to ODP value increase atmosphere. The same variations are analyzed for the CFC-free atmosphere of 1960s conditions for the anthropogenically loaded atmosphere in the 21st century according to the known IPCC- A scenario (business as usual). Recommendations of proper ways of ODP calculations are proposed for practically important cases

  20. Plutonium in depleted uranium penetrators

    International Nuclear Information System (INIS)

    Depleted Uranium (DU) penetrators used in the recent Balkan conflicts have been found to be contaminated with trace amounts of transuranic materials such as plutonium. This contamination is usually a consequence of DU fabrication being carried out in facilities also using uranium recycled from spent military and civilian nuclear reactor fuel. Specific activities of 239+240 Plutonium generally in the range 1 to 12 Bq/kg have been found to be present in DU penetrators recovered from the attack sites of the 1999 NATO bombardment of Kosovo. A DU penetrator recovered from a May 1999 attack site at Bratoselce in southern Serbia and analysed by University College Dublin was found to contain 43.7 +/- 1.9 Bq/kg of 239+240 Plutonium. This analysis is described. An account is also given of the general population radiation dose implications arising from both the DU itself and from the presence of plutonium in the penetrators. According to current dosimetric models, in all scenarios considered likely ,the dose from the plutonium is estimated to be much smaller than that due to the uranium isotopes present in the penetrators. (author)

  1. The Novel CFTR Mutation A457P in a Male with a Delayed Diagnosis of Cystic Fibrosis

    Directory of Open Access Journals (Sweden)

    Kate H. Cole

    2011-01-01

    Full Text Available Cystic fibrosis (CF is an autosomal recessive disease that may be caused by more than 1000 different mutations in the cystic fibrosis transmembrane conductance regulator (CFTR gene. We describe the case of a CF patient who was initially diagnosed at 16 years of age after presenting with mild respiratory compromise and pancreatic sufficiency. When genetic testing was first performed using a CF mutation panel, only a single F508del CFTR allele was identified. We subsequently performed testing, which revealed a previously unreported mutation: A457P (p.Ala457Pro, c.1369G>C. The patient's clinical course through adulthood is described, and genotype-phenotype correlation is discussed. The A457P mutation appears to confer a relatively mild phenotype, as is usually observed with CFTR class IV–VI defects. With the advent of more comprehensive and widely available genetic testing techniques, identification of CF genotypes in patients with milder disease variants may help stratify patients for targeted therapy and prevent late complications of the disease.

  2. Vitamin D depletion aggravates hypertension and target-organ damage

    DEFF Research Database (Denmark)

    Andersen, Louise Bjørkholt; Przybyl, Lukasz; Haase, Nadine; von Versen-Höynck, Frauke; Qadri, Fatimunnisa; Jørgensen, Jan Stener; Sorensen, Grith Lykke; Fruekilde, Palle; Poglitsch, Marko; Szijarto, István; Gollasch, Maik; Peters, Joerg; Muller, Dominik N; Christesen, Henrik Thybo; Dechend, Ralf

    2015-01-01

    BACKGROUND: We tested the controversial hypothesis that vitamin D depletion aggravates hypertension and target-organ damage by influencing renin. METHODS AND RESULTS: Four-week-old double-transgenic rats (dTGR) with excess angiotensin (Ang) II production due to overexpression of the human renin (h......REN) and angiotensinogen (hAGT) genes received vitamin D-depleted (n=18) or standard chow (n=15) for 3 weeks. The depleted group had very low serum 25-hydroxyvitamin D levels (mean±SEM; 3.8±0.29 versus 40.6±1.19 nmol/L) and had higher mean systolic BP at week 5 (158±3.5 versus 134.6±3.7 mm Hg, P<0......, hREN, and rRen were increased by vitamin D depletion. Regulatory T cells in the spleen and in the circulation were not affected. Ang metabolites, including Ang II and the counter-regulatory breakdown product Ang 1 to 7, were significantly up-regulated in the vitamin D-depleted groups, while ACE-1...

  3. Antarctic winter mercury and ozone depletion events over sea ice

    Science.gov (United States)

    Nerentorp Mastromonaco, M.; Gårdfeldt, K.; Jourdain, B.; Abrahamsson, K.; Granfors, A.; Ahnoff, M.; Dommergue, A.; Méjean, G.; Jacobi, H.-W.

    2016-03-01

    During atmospheric mercury and ozone depletion events in the springtime in polar regions gaseous elemental mercury and ozone undergo rapid declines. Mercury is quickly transformed into oxidation products, which are subsequently removed by deposition. Here we show that such events also occur during Antarctic winter over sea ice areas, leading to additional deposition of mercury. Over four months in the Weddell Sea we measured gaseous elemental, oxidized, and particulate-bound mercury, as well as ozone in the troposphere and total and elemental mercury concentrations in snow, demonstrating a series of depletion and deposition events between July and September. The winter depletions in July were characterized by stronger correlations between mercury and ozone and larger formation of particulate-bound mercury in air compared to later spring events. It appears that light at large solar zenith angles is sufficient to initiate the photolytic formation of halogen radicals. We also propose a dark mechanism that could explain observed events in air masses coming from dark regions. Br2 that could be the main actor in dark conditions was possibly formed in high concentrations in the marine boundary layer in the dark. These high concentrations may also have caused the formation of high concentrations of CHBr3 and CH2I2 in the top layers of the Antarctic sea ice observed during winter. These new findings show that the extent of depletion events is larger than previously believed and that winter depletions result in additional deposition of mercury that could be transferred to marine and terrestrial ecosystems.

  4. Vacancy Formation Enthalpy in Polycrystalline Depleted Uranium

    Science.gov (United States)

    Lund, K. R.; Lynn, K. G.; Weber, M. H.; Okuniewski, M. A.

    2013-06-01

    Positron Annihilation Spectroscopy was performed as a function of temperature and beam energy on polycrystalline depleted uranium (DU) foil. Samples were run with varying heat profiles all starting at room temperature. While collecting Doppler-Broadening data, the temperature of the sample was cycled several times. The first heat cycle shows an increasing S-parameter near temperatures of 400K to 500K much lower than the first phase transition of 941K indicating increasing vacancies possibly due to oxygen diffusion from the bulk to the surface. Vacancy formation enthalpies were calculated fitting a model to the data to be 1.6± 0.16 eV. Results are compared to previous work [3,4].

  5. Depleted Uranium Penetrators : Hazards and Safety

    Directory of Open Access Journals (Sweden)

    S. S. Rao

    1997-01-01

    Full Text Available The depleted uranium (DU alloy is a state-of-the-art material for kinetic energy penetrators due to its superior ballistic performance. Several countries use DU penetrators in their main battle tanks. There is no gamma radiation hazard to the crew members from stowage of DO rounds. Open air firing can result in environmental contamination and associated hazards due to airborne particles containing essentially U/sub 3/0/sub 8/ and UO/sub 2/. Inhalation of polluted air only through respirators or nose masks and refraining form ingestion of water or food materials from contaminated environment are safety measures for avoiding exposure to uranium and its toxicity. Infusion of sodium bicarbonate helps in urinary excretion of uranium that may have entered the body.

  6. 乙醇对于豚鼠胰腺导管上皮细胞腔面膜侧 CFTR 介导的 HCO3-分泌的影响%Effect of ethanol on HCO 3- secretion mediated by CFTR from guinea - pig pancreatic duct cells. SONG Ying1,DING Xiang - fu2,WANG

    Institute of Scientific and Technical Information of China (English)

    宋莹; 丁相福; 王晓东; 段瑞峰; 石黑洋; 刘佰纯

    2016-01-01

    Objective To investigate the effect of ethanol on HCO3 - secretion induced by CFTR from guinea - pig pancreatic duct cells and to analyse the mechanisms of alcoholic pancreatitis. Methods Interlobular duct segments( diameter,100 ~ 150 μm)were microdissected under a dissection microscope using sharp needles. The lumen of the interlobular duct segment was microperfused. The bath and luminal solutions were modified separately. Intracellular pH(pHi)in the duct cells was estimated by microfluorometry using the pH - sensitive fluoroprobe BCECF. Transepithelial fluxes of HCO3 - were estimated under the anion gradients favoring rapid exchange of intracellular HCO3 - . Results ①When in vitro pancreatic duct pipe cavity,when filled with high concentration of sodium bicarbonate buffer micro pHi from epithelial cells after alkaline pH unit recovery rate was was 0. 048 ± 0. 009 pH unit·min - 1(n = 9),add 1 mm when ethanol pHi decline accelerated significantly(0. 066 ± 0. 005 pH unit·min - 1 ,n = 7,t = 0. 0009,P < 0. 05). ②Luminal application of CFTRinh - 172(10 μM)significantly( P < 0. 05)inhibited apical HCO3 - secretion(0. 039 ± 0. 010 pH unit·min - 1 ,n = 7,t = 0. 001). ③When the duct was stimulated with ethanol,luminal application of CFTRinh - 172 decrease the rate of pHi(0. 054 ± 0. 008 pH unit·min - 1 ,n = 7,t = 0. 0015,P < 0. 05). Conclusion Ethanol stimulated api-cal HCO3 - secretion of guinea - pig pancreatic ducts. The augmentation by ethanol appears to be mediated by CFTR.%目的:通过研究乙醇对于豚鼠胰腺导管上皮细胞腔面膜侧囊性纤维化转膜传导因子( CFTR)介导的碳酸氢根离子(HCO3-)分泌的影响,探讨酒精性胰腺炎的发病机制。方法运用显微解剖技术分离豚鼠胰腺导管(直径100~150μm),使用微灌流技术置换管腔内液体。采用荧光显微测定技术检测细胞内 pH 值变化,并计算出腔面膜侧HCO3-分泌率,进而探讨乙醇在 CFTR 介导的 HCO3-

  7. Depletion sensitivity predicts unhealthy snack purchases

    NARCIS (Netherlands)

    Salmon, Stefanie J.; Adriaanse, Marieke A.; Fennis, Bob M.; De Vet, Emely; De Ridder, Denise T D

    2016-01-01

    The aim of the present research is to examine the relation between depletion sensitivity - a novel construct referring to the speed or ease by which one's self-control resources are drained - and snack purchase behavior. In addition, interactions between depletion sensitivity and the goal to lose we

  8. Depletion sensitivity predicts unhealthy snack purchases

    NARCIS (Netherlands)

    Salmon, Stefanie J.; Adriaanse, Marieke A.; Fennis, Bob M.; Vet, De Emely; Ridder, De Denise T.D.

    2016-01-01

    The aim of the present research is to examine the relation between depletion sensitivity - a novel construct referring to the speed or ease by which one's self-control resources are drained - and snack purchase behavior. In addition, interactions between depletion sensitivity and the goal to lose

  9. Tritium transport vessel using depleted uranium

    Energy Technology Data Exchange (ETDEWEB)

    Heung, L.K.

    1995-01-01

    A tritium transport vessel using depleted uranium was tested in the laboratory using deuterium and protium. The vessel contains 0.5 kg of depleted uranium and can hold up to 18 grams of tritium. The conditions for activation, tritium loading and tritium unloading were defined. The safety aspects that included air-ingress, tritium diffusion, temperature and pressure potentials were evaluated.

  10. Oil depletion and terms of trade

    OpenAIRE

    Irimia-Vladu, Marina; Thompson, Henry

    2007-01-01

    A model of the international oil market model with optimal depletion and offer curves suggests importers face a backward bending offer curve. An oil tariff would then raise oil imports and lower the price of oil including the tariff. Simulations of price and extraction paths for the coming century provide insight into the future of oil depletion and terms of trade.

  11. Plasma depletion layer: Magnetosheath flow structure and forces

    Directory of Open Access Journals (Sweden)

    Y. L. Wang

    2004-03-01

    Full Text Available The plasma depletion layer (PDL is a layer on the sunward side of the magnetopause with lower plasma density and higher magnetic field compared to the corresponding upstream magnetosheath values. In a previous study, we have validated the UCLA global (MHD model in studying the formation of the PDL by comparing model results, using spacecraft solar wind observations as the driver, with in situ PDL observations. In this study, we extend our previous work and examine the detailed MHD forces responsible for the PDL formation. We argue that MHD models, instead of gasdynamic models, should be used to study the PDL, because gasdynamic models cannot produce the PDL on the sunward side of the magnetopause. For northward (IMF, flux tube depletion occurs in almost all the subsolar magnetosheath. However, the streamlines closest to the magnetopause and the stagnation line show the greatest depletion. The relative strength of the various MHD forces changes along these streamlines. Forces along a flux tube at different stages of its depletion in the magnetosheath are analyzed. We find that a strong plasma pressure gradient force along the magnetic field at the bow shock and a pressure gradient force along the flux tube within the magnetosheath usually exist pushing plasma away from the equatorial plane to deplete the flux tube. More complex force structures along the flux tube are found close to the magnetopause. This new, more detailed description of flux tube depletion is compared with the results of Zwan and Wolf (1976 and differences are found. Near the magnetopause, the pressure gradient force along the flux tube either drives plasma away from the equatorial plane or pushes plasma toward the equatorial plane. As a result, a slow mode structure is seen along the flux tube which might be responsible for the observed two-layered slow mode structures.

    Key words. Magnetospheric physics (magnetosheath; solar wind-magnetosphere interactions. Space

  12. Specification for the VERA Depletion Benchmark Suite

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kang Seog [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-12-17

    CASL-X-2015-1014-000 iii Consortium for Advanced Simulation of LWRs EXECUTIVE SUMMARY The CASL neutronics simulator MPACT is under development for the neutronics and T-H coupled simulation for the pressurized water reactor. MPACT includes the ORIGEN-API and internal depletion module to perform depletion calculations based upon neutron-material reaction and radioactive decay. It is a challenge to validate the depletion capability because of the insufficient measured data. One of the detoured methods to validate it is to perform a code-to-code comparison for benchmark problems. In this study a depletion benchmark suite has been developed and a detailed guideline has been provided to obtain meaningful computational outcomes which can be used in the validation of the MPACT depletion capability.

  13. Depletion of the ozone layer and its biological consequences

    International Nuclear Information System (INIS)

    The high concentration of ozone in the stratosphere serves as a protective shield against the harmful ultraviolet radiation from the sun. The increase in human activities is the main cause of the depletion of this ozone layer. The continued depletion of ozone layer will result in an increased exposure ultraviolet radiation which will have serve biological consequences. In this paper a detailed review of ozone, its production and decomposition alongwith its main depletors chlorofluoro-carbons is presented. The ozone data for Quetta Valley for the period 1960-90 is analysed. The biological consequences of increased ultraviolet radiation due to reduction in ozone layer are also discussed. (author)

  14. Characterization of a Depleted Monolithic Active Pixel Sensor (DMAPS) prototype

    International Nuclear Information System (INIS)

    New monolithic pixel detectors integrating CMOS electronics and sensor on the same silicon substrate are currently explored for particle tracking in future HEP experiments, most notably at the LHC . The innovative concept of Depleted Monolithic Active Pixel Sensors (DMAPS) is based on high resistive silicon bulk material enabling full substrate depletion and the application of an electrical drift field for fast charge collection, while retaining full CMOS capability for the electronics. The technology (150 nm) used offers quadruple wells and allows to implement the pixel electronics with independently isolated N- and PMOS transistors. Results of initial studies on the charge collection and sensor performance are presented

  15. Characterization of a Depleted Monolithic Active Pixel Sensor (DMAPS) prototype

    Science.gov (United States)

    Obermann, T.; Havranek, M.; Hemperek, T.; Hügging, F.; Kishishita, T.; Krüger, H.; Marinas, C.; Wermes, N.

    2015-03-01

    New monolithic pixel detectors integrating CMOS electronics and sensor on the same silicon substrate are currently explored for particle tracking in future HEP experiments, most notably at the LHC . The innovative concept of Depleted Monolithic Active Pixel Sensors (DMAPS) is based on high resistive silicon bulk material enabling full substrate depletion and the application of an electrical drift field for fast charge collection, while retaining full CMOS capability for the electronics. The technology (150 nm) used offers quadruple wells and allows to implement the pixel electronics with independently isolated N- and PMOS transistors. Results of initial studies on the charge collection and sensor performance are presented.

  16. Simulating distinguish enriched uranium from depleted uranium by activation method

    International Nuclear Information System (INIS)

    Detecting uranium material is an important work in arms control Active detection is an efficient method for uranium material. The paper focuses on the feasibility that can distinguish the enriched uranium and the depleted uranium by MCNP program. It can distinguish the enriched uranium and the depleted uranium by the curve of relationship between fission rate of uranium material and thickness of moderator.Advantages of 252Cf and 14 MeV neutron sources are discussed in detecting uranium material through calculation. The results show that 252Cf neutron source is better than 14 MeV one. Delayed neutrons are more easily detected than delayed gamma ray at measurement aspect. (authors)

  17. Long-term management and use of depleted uranium

    International Nuclear Information System (INIS)

    The products resulting from the process of enrichment of natural uranium, or reprocessed uranium, are enriched uranium products as the light fraction and depleted uranium (uranium tails) as the heavy fraction. If the source material is natural uranium, the mass ratios of uranium products and uranium tails can be derived relatively easily from the required enrichment level of the uranium product (product assay (% of U-235)) and the selected depletion level of the uranium tails (tails assay (% of U-235)). The paper discusses among other aspects the dependence of the tails mass on the required enrichment level of the relevant uranium product, for various tails assays. (orig./CB)

  18. Depleted uranium determination at the Novi Sad low level facility

    International Nuclear Information System (INIS)

    Natural uranium determination in environmental samples at the low-level gamma-spectroscopy laboratory of the Faculty of Science in Novi Sad has more than 20 years long tradition. When the issue of depleted uranium emerged the experimental advantages of the measuring equipment (GMX type of HPGe detector with enhanced efficiency below 100 keV, and iron low level shielding) where fully exploited. A detection technique selective for depleted uranium was developed. The details of this method together with the results for about 100 samples (soil, plants, water, food) are presented, and discussed. (author)

  19. Mutations in CFTR gene and clinical correlation in Argentine patients with congenital bilateral absence of the vas deferens Correlación de las características clínicas con mutaciones del gen CFTR en pacientes argentinos con ausencia bilateral congénita de vasos deferentes

    OpenAIRE

    Levy, Estrella M; Patricia Granados; Vanesa Rawe; Santiago Brugo Olmedo; María C Luna; Eduardo Cafferata; Omar H Pivetta

    2004-01-01

    Congenital bilateral absence of the vas deferens (CBAVD) is a form of male infertility in which mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have been identified. Here we identify different mutations of CFTR and the poly-T variant of intron 8 (IVS8) in Argentine patients and analyze sweat test values and clinical characteristic related to Cystic Fibrosis (CF). For counseling purposes the two most frequent mutations in Argentine CF population: DF508 and G542...

  20. The combined depletion of monoamines alters the effectiveness of subthalamic deep brain stimulation.

    Science.gov (United States)

    Faggiani, Emilie; Delaville, Claire; Benazzouz, Abdelhamid

    2015-10-01

    Non-motor symptoms of Parkinson's disease are under-studied and therefore not well treated. Here, we investigated the role of combined depletions of dopamine, norepinephrine and/or serotonin in the manifestation of motor and non-motor deficits in the rat. Then, we studied the impact of these depletions on the efficacy of deep brain stimulation of the subthalamic nucleus (STN-DBS). We performed selective depletions of dopamine, norepinephrine and serotonin, and the behavioral effects of different combined depletions were investigated using the open field, the elevated plus maze and the forced swim test. Bilateral dopamine depletion alone induced locomotor deficits associated with anxiety and mild "depressive-like" behaviors. Although additional depletions of norepinephrine and/or serotonin did not potentiate locomotor and anxiety disorders, combined depletions of the three monoamines dramatically exacerbated "depressive-like" behavior. STN-DBS markedly reversed locomotor deficits and anxiety behavior in animals with bilateral dopamine depletion alone. However, these improvements were reduced or lost by the additional depletion of norepinephrine and/or serotonin, indicating that the depletion of these monoamines may interfere with the antiparkinsonian efficacy of STN-DBS. Furthermore, our results showed that acute STN-DBS improved "depressive-like" disorder in animals with bilateral depletion of dopamine and also in animals with combined depletions of the three monoamines, which induced severe immobility in the forced swim test. Our data highlight the key role of monoamine depletions in the pathophysiology of anxiety and depressive-like disorders and provide the first evidence of their negative consequences on the efficacy of STN-DBS upon the motor and anxiety disorders in the context of Parkinson's disease. PMID:26206409

  1. Past and future contribution of global groundwater depletion to sea-level rise

    OpenAIRE

    Wada, Yoshihide; van Beek, Ludovicus P. H.; Sperna Weiland, Frederiek C.; Chao, Benjamin F.; Wu, Yun-Hao; Bierkens, Marc F. P.

    2012-01-01

    Recent studies suggest the increasing contribution of groundwater depletion to global sea-level rise. Groundwater depletion has more than doubled during the last decades, primarily due to increase in water demand, while the increase in water impoundments behind dams has been tapering off since the 1990s. As a result, the contribution of groundwater depletion to sea-level rise is likely to dominate over those of other terrestrial water sources in the coming decades. Yet, no projections into th...

  2. Interactions of bromine, chlorine, and iodine photochemistry during ozone depletions in Barrow, Alaska

    OpenAIRE

    Thompson, C. R.; P. B. Shepson; Liao, J.; Huey, L.G.; E. C. Apel; Cantrell, C. A.; Flocke, F.; Orlando, J.; Fried, A.; Hall, S. R; R. S. Hornbrook; D. J. Knapp; Mauldin III, R. L; Montzka, D. D.; B. C. Sive

    2014-01-01

    The springtime depletion of tropospheric ozone in the Arctic is known to be caused by active halogen photochemistry resulting from halogen atom precursors emitted from snow, ice, or aerosol surfaces. The role of bromine in driving ozone depletion events (ODEs) has been generally accepted, but much less is known about the role of chlorine radicals in ozone depletion chemistry. While the potential impact of iodine in the High Arctic is more uncertain, there ha...

  3. Interactions of bromine, chlorine, and iodine photochemistry during ozone depletions in Barrow, Alaska

    OpenAIRE

    Thompson, C. R.; P. B. Shepson; Liao, J.; Huey, L.G.; E. C. Apel; Cantrell, C. A.; Flocke, F.; Orlando, J.; Fried, A.; Hall, S. R; R. S. Hornbrook; D. J. Knapp; Mauldin III, R. L; Montzka, D. D.; B. C. Sive

    2015-01-01

    The springtime depletion of tropospheric ozone in the Arctic is known to be caused by active halogen photochemistry resulting from halogen atom precursors emitted from snow, ice, or aerosol surfaces. The role of bromine in driving ozone depletion events (ODEs) has been generally accepted, but much less is known about the role of chlorine radicals in ozone depletion chemistry. While the potential impact of iodine in the High Arctic is more uncertain, there have been indicatio...

  4. Funciones de los canales iónicos CFTR y ENAC en la fibrosis quística

    Directory of Open Access Journals (Sweden)

    Alejandra G. Palma

    2014-04-01

    Full Text Available La fibrosis quística se debe a la ausencia o defecto del canal transmembrana regulador de la fibrosis quística (CFTR, un canal de cloruro codificado en el gen cftr que juega un papel clave en la homeostasis del agua e iones. El CFTR es activado por el AMPc y se localiza en las membranas apicales y basolaterales de las vías aéreas, intestino y glándulas exocrinas. Una de sus funciones primarias en los pulmones es mantener la capa de líquido superficial a través de su función de canal y regular el canal epitelial de sodio sensible al amiloride (ENaC. Se han identificado más de 1900 mutaciones en el gen cftr. La enfermedad se caracteriza por secreciones viscosas en las glándulas exocrinas y por niveles elevados de cloruro de sodio en el sudor. En la fibrosis quística el CFTR no funciona y el ENaC está desregulado; el resultado es un aumento en la reabsorción de sodio y agua con la formación de un líquido viscoso. En las glándulas sudoríparas tanto el Na+ como el Cl- se retienen en el lumen causando una pérdida de electrolitos durante la sudoración y el NaCl se elimina al sudor. Así, los niveles elevados de NaCl son la base del test del sudor inducido por pilocarpina, un método de diagnóstico para la enfermedad. En esta revisión se discuten los movimientos de Cl- y Na+ en las glándulas sudoríparas y pulmón así como el papel del ENaC en la patogénesis de la enfermedad.

  5. Application Progress in CFTR Inhibitors in the Treatment of Secretory Diarrhea%囊性纤维化跨膜传导调节因子抑制药在分泌性腹泻中的应用研究进展

    Institute of Scientific and Technical Information of China (English)

    徐倩倩; 王玉波; 王艳萍; 郭时金; 张志美; 沈志强

    2015-01-01

    Secretory diarrhea provides a major health challenge worldwide, which is one of the most important reasons for children morbidity and death. The activation of Cl- channels in intestinal epithelial cells resulting in the excessive fluid secretion in the intestine is the main reason of diarrhea caused by enterotoxins. In diarrhea caused by cholera and the other bacterial enterotoxins, cystic fibrosis transmembrane conductance regulator ( CFTR) is the main cAMP-control Cl- channel to promote the fluid secretion in epithelial cells. Therefore, CFTR inhibitors are the new choices for secretory diarrhea. CFTR inhibitors include thiazolidinone, glycine hydrazide and quinoxalinedione chemical classes, and some components from natural plants also exhibit CFTR inhibition activity, however, further studies should be done.%分泌性腹泻威胁着全球健康,是儿童发病和死亡的主要原因之一。肠上皮细胞腔内Cl-通道激活导致肠道液体过度分泌是肠毒素引起腹泻的主要原因。在霍乱及其他细菌肠毒素引发的腹泻中,囊性纤维化跨膜传导调节因子( cystic fibrosis transmembrane conductance regulator, CFTR)是主要的cAMP-调节Cl-通道,其主要功能是促进上皮细胞液体分泌。利用肠上皮细胞CFTR抑制药抗分泌性腹泻是一种新途径。已有的CFTR抑制药有噻唑啉酮类、甘氨酸酰肼类和喹喔啉二酮等。同时,从天然植物中提取分离的一些成分也具有CFTR抑制作用,但研究还不够深入。因此,对CFTR抑制药的研究进展进行了综述。

  6. Modeling of precipitation and Cr depletion profiles of Inconel 600 during heat treatments and LSM procedure

    International Nuclear Information System (INIS)

    A model based on the thermodynamic and kinetic was conducted to simulate the Cr depletion profiles near the grain boundary in Inconel 600 during the heat treatments and laser surface melting (LSM) process using Thermo-Calc and Dictra code. Based on the good agreement of Cr concentration distribution during heat treatments measured by experiments, the microsegregation of Cr induced by cellular microstructure formed during the LSM process was also modeled. The Cr depletion profile was evaluated using the Cr depletion area below the critical Cr concentration for intergranular cracking/intergranular stress corrosion cracking (IGC/IGSCC) susceptibility (8 mass%). Comparing with the result of Streicher test, the Cr depletion area calculated showed good coherence with the IGC/IGSCC susceptibility. The sample after SR + LTS treatment with the largest Cr depletion area showed the worst IGC/IGSCC resistance, while, the sample after LSM process with the smaller Cr depletion area showed the excellent IGC/IGSCC resistance

  7. Monte Carlo solver for UWB1 nuclear fuel depletion code

    International Nuclear Information System (INIS)

    Highlights: • A new Monte Carlo solver was developed in order to speed-up depletion calculations. • For LWR model, UWB1 Monte Carlo solver is on average 10 times faster than MCNP6. • The UWB1 code will allow faster calculation analysis of BA parameters in fuel design. - Abstract: Recent nuclear reactor burnable absorber research tries to introduce new materials in the nuclear fuel. As a part of this effort, a fast computational tool is being developed for the advanced nuclear fuel. The first version of the newly developed UWB1 fast nuclear fuel depletion code significantly reduced calculation time by omitting the solution step for the Boltzmann transport equation. However, estimation of neutron multiplication factor during depletion was not sufficiently calculated. Therefore, at least one transport calculation for fuel depletion is necessary. This paper presents a new Monte Carlo solver that is implemented into the UWB1 code. The UWB1 Monte Carlo solver calculates neutron multiplication factor and neutron flux in the fuel for collapsed cross sections. Accuracy of the solver is supported by using current nuclear data stored in the ENDF/B-VII.1 library. Speed of the solver is the product of development focusing on minimization of CPU utilization at the expense of RAM demands. The UWB1 Monte Carlo solver is approximately 14 times faster than the MCNP6 reference code when one transport equation solution within fuel depletion is compared. Another speed-up can be achieved by employing advanced depletion scheme in the coupled transport and burnup equations. The resulting faster code will be used in optimization studies for ideal burnable absorber material selection where many various materials and concentrations will be evaluated

  8. A Monte Carlo Study of Influences on Depletion Force from Another Large Sphere in Colloidal Suspensions

    Institute of Scientific and Technical Information of China (English)

    XIAO Chang-Ming; GUO Ji-Yuan; HU Ping

    2006-01-01

    @@ According to the acceptance ratio method, the influences on the depletion interactions between a large sphere and a plate from another closely placed large sphere are studied by Monte Carlo simulation. The numerical results show that both the depletion potential and depletion force are affected by the presence of the closely placed large sphere; the closer the large sphere are placed to them, the larger the influence will be. Furthermore, the influences on the depletion interactions from another large sphere are more sensitive to the angle than to the distance.

  9. Rhodium in-core detector sensitivity depletion, cycles 2-5

    International Nuclear Information System (INIS)

    Sensitivity depletion of two rhodium (Rh) self-powered neutron detectors (SPNDs) has been measured since July 1976 at the Oconee 2 pressurized water reactor (PWR). The detectors were positioned inside the reactor core throughout the measurement period. Depletion has been determined as a function of electric charge released by each detector. The goal of the project is the empirical definition of the depletion characteristics over the operating life-time of the Rh detector. Results to date show that the sensitivity depletion rate of the Rh detector in the PWR is highly linear with charge released from the detector

  10. Possible ozone depletions following nuclear explosions

    Science.gov (United States)

    Whitten, R. C.; Borucki, W. J.; Turco, R. P.

    1975-01-01

    The degree of depletion of the ozone layer ensuing after delivery of strategic nuclear warheads (5000 and 10,000 Mton) due to production of nitrogen oxides is theoretically assessed. Strong depletions are calculated for 16-km and 26-km altitudes, peaking 1-2 months after detonation and lasting for three years, while a significant depletion at 36 km would peak after one year. Assuming the explosions occur between 30 and 70 deg N, these effects should be much more pronounced in this region than over the Northern Hemisphere as a whole. It is concluded that Hampson's concern on this matter (1974) is well-founded.-

  11. DIRECT MEASUREMENT OF WEAK DEPLETION FORCE BETWEEN TWO SURFACES*

    Institute of Scientific and Technical Information of China (English)

    Xiang-jun Gong; Xiao-chen Xing; Xiao-ling Wei; To Ngai

    2011-01-01

    In a mixture of colloidal particles and polymer molecules, the particles may experience an attractive “depletion force” if the size of the polymer molecule is larger than the interparticle separation. This is because individual polymer molecules experience less conformational entropy if they stay between the particles than they escape the inter-particle space,which results in an osmotic pressure imbalance inside and outside the gap and leads to interparticle attraction. This depletion force has been the subject of several studies since the 1980s, but the direct measurement of this force is still experimentally challenging as it requires the detection of energy variations of the order of kBT and beyond. We present here our results for applying total internal reflection microscopy (TIRM) to directly measure the interaction between a free-moving particle and a flat surface in solutions consisting of small water-soluble organic molecules or polymeric surfactants. Our results indicate that stable nanobubbles (ca. 150 nm) exist free in the above aqueous solutions. More importantly, the existence of such nanobubbles induces an attraction between the spherical particle and flat surface. Using TIRM, we are able to directly measure such weak interaction with a range up to 100 nm. Furthermore, we demonstrate that by employing thermo-sensitive microgel particles as a depleting agent, we are able to quantitatively measure and reversibly control kBT-scale depletion attraction as function of solution pH.

  12. Real depletion in nodal diffusion codes

    International Nuclear Information System (INIS)

    The fuel depletion is described by more than one hundred fuel isotopes in the advanced lattice codes like HELIOS, but only a few fuel isotopes are accounted for even in the advanced steady-state diffusion codes. The general assumption that the number densities of the majority of the fuel isotopes depend only on the fuel burnup is seriously in error if high burnup is considered. The real depletion conditions in the reactor core differ from the asymptotic ones at the stage of lattice depletion calculations. This study reveals which fuel isotopes should be explicitly accounted for in the diffusion codes in order to predict adequately the real depletion effects in the core. A somewhat strange conclusion is that if the real number densities of the main fissionable isotopes are not explicitly accounted for in the diffusion code, then Sm-149 should not be accounted for either, because the net error in k-inf is smaller (Authors)

  13. Fully Depleted Charge-Coupled Devices

    International Nuclear Information System (INIS)

    We have developed fully depleted, back-illuminated CCDs that build upon earlier research and development efforts directed towards technology development of silicon-strip detectors used in high-energy-physics experiments. The CCDs are fabricated on the same type of high-resistivity, float-zone-refined silicon that is used for strip detectors. The use of high-resistivity substrates allows for thick depletion regions, on the order of 200-300 um, with corresponding high detection efficiency for near-infrared and soft x-ray photons. We compare the fully depleted CCD to the p-i-n diode upon which it is based, and describe the use of fully depleted CCDs in astronomical and x-ray imaging applications

  14. Polar stratospheric clouds and ozone depletion

    Science.gov (United States)

    Toon, Owen B.; Turco, Richard P.

    1991-01-01

    A review is presented of investigations into the correlation between the depletion of ozone and the formation of polar stratospheric clouds (PSCs). Satellite measurements from Nimbus 7 showed that over the years the depletion from austral spring to austral spring has generally worsened. Approximately 70 percent of the ozone above Antarctica, which equals about 3 percent of the earth's ozone, is lost during September and October. Various hypotheses for ozone depletion are discussed including the theory suggesting that chlorine compounds might be responsible for the ozone hole, whereby chlorine enters the atmosphere as a component of chlorofluorocarbons produced by humans. The three types of PSCs, nitric acid trihydrate, slowly cooling water-ice, and rapidly cooling water-ice clouds act as important components of the Antarctic ozone depletion. It is indicated that destruction of the ozone will be more severe each year for the next few decades, leading to a doubling in area of the Antarctic ozone hole.

  15. Depleted UF6 programmatic environmental impact statement

    International Nuclear Information System (INIS)

    The US Department of Energy has developed a program for long-term management and use of depleted uranium hexafluoride, a product of the uranium enrichment process. As part of this effort, DOE is preparing a Programmatic Environmental Impact Statement (PEIS) for the depleted UF6 management program. This report duplicates the information available at the web site (http://www.ead.anl.gov/web/newduf6) set up as a repository for the PEIS. Options for the web site include: reviewing recent additions or changes to the web site; learning more about depleted UF6 and the PEIS; browsing the PEIS and related documents, or submitting official comments on the PEIS; downloading all or part of the PEIS documents; and adding or deleting one's name from the depleted UF6 mailing list

  16. Initial PVO Evidence of Electron Depletion Signatures Downstream of Venus

    Science.gov (United States)

    Intriligator, D. S.; Hartle, R. E.; Perez-de-Tejada, H.; Siscoe, G. L.

    1993-01-01

    This first analysis of Pioneer Venus Orbiter (PVO) plasma analyzer electron measurements obtained in early 1992 during the PVO entry phase of the mission indicates the presence downstream from the terminator of a depletion or "bite out" of energetic ionosheath electrons similar to that observed on Mariner 10. There is more than one possible explanation for this energetic electron depletion. If it is due to atmospheric scattering, the electrons traveling along draped magnetic flux tubes that thread through the Venus neutral atmosphere would lose energy from impact ionization with oxygen. The cross-section for such electron impact ionization of oxygen has a peak near 100 eV, and it remains high above this energy, so atmospheric loss could provide a natural process for electrons at these energies to be selectively removed. In this case, our results are consistent with the Kar et al. (1994) study of PVO atmospheric entry ion mass spectrometer data which indicates that electron impact plays a significant role in maintaining the nightside ionosphere. Although it is appealing to interpret the energetic electron depletion in terms of direct atmospheric scattering, alternatively it could result from strong draping which connects the depletion region magnetically to the weak downstream bow shock and thereby reduces the electron source strength.

  17. C18O Depletion in Starless Cores in Taurus

    CERN Document Server

    Ford, Amanda Brady

    2011-01-01

    We present here findings for C18O depletion in eight starless cores in Taurus: TMC-2, L1498, L1512, L1489, L1517B, L1521E, L1495A-S, and L1544. We compare observations of the C18O J=2-1 transition taken with the ALMA prototype receiver on the Heinrich Hertz Submillimeter Telescope to results of radiative transfer modeling using RATRAN. We use temperature and density profiles calculated from dust continuum radiative transfer models to model the C18O emission. We present modeling of three cores, TMC-2, L1489, and L1495A-S, which have not been modeled before and compare our results for the five cores with published models. We find that all of the cores but one, L1521E, are substantially depleted. We also find that varying the temperature profiles of these model cores has a discernable effect, and varying the central density has an even larger effect. We find no trends with depletion radius or depletion fraction with the density or temperature of these cores, suggesting that the physical structure alone is insuff...

  18. Depleted Bulk Heterojunction Colloidal Quantum Dot Photovoltaics

    KAUST Repository

    Barkhouse, D. Aaron R.

    2011-05-26

    The first solution-processed depleted bulk heterojunction colloidal quantum dot solar cells are presented. The architecture allows for high absorption with full depletion, thereby breaking the photon absorption/carrier extraction compromise inherent in planar devices. A record power conversion of 5.5% under simulated AM 1.5 illumination conditions is reported. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Radiative characteristics of depleted uranium bomb and it is protection

    International Nuclear Information System (INIS)

    Based on the developing process of depleted uranium bombs described in the first part, the radiative characteristics and mechanism of depleted uranium bombs are analyzed emphatically. The deeper discussion on protection of depleted uranium bombs is proceeded

  20. Levels of depleted uranium in Kosovo soils

    International Nuclear Information System (INIS)

    The United Nations Environment Programme has performed a field survey at 11 sites located in Kosovo, where depleted uranium (DU) ammunitions were used by the North Atlantic Treaty Organization (NATO) during the last Balkans conflict (1999). Soil sampling was performed to assess the spread of DU ground contamination around and within the NATO target sites and the migration of DU along the soil profile. The 234U/238U and 235U/238U activity concentration ratios have been used as an indicator of natural against anthropogenic sources of uranium. The results show that levels of 238U activity concentrations in soils above 100 Bq.kg-1 can be considered a 'tracer' of the presence of DU in soils. The results also indicate that detectable ground surface contamination by DU is limited to areas within a few metres from localised points of concentrated contamination caused by penetrator impacts. Vertical distribution of DU along the soil profile is measurable up to a depth of 10-20 cm. This latter aspect is of particular relevance for the potential risk of future contamination of groundwater. (author)

  1. Levels of depleted uranium in Kosovo soils

    Energy Technology Data Exchange (ETDEWEB)

    Sansone, U.; Stellato, L.; Jia, G.; Rosamilia, S.; Gaudino, S.; Barbizzi, S.; Belli, M

    2001-07-01

    The United Nations Environment Programme has performed a field survey at 11 sites located in Kosovo, where depleted uranium (DU) ammunitions were used by the North Atlantic Treaty Organization (NATO) during the last Balkans conflict (1999). Soil sampling was performed to assess the spread of DU ground contamination around and within the NATO target sites and the migration of DU along the soil profile. The {sup 234}U/{sup 238}U and {sup 235}U/{sup 238}U activity concentration ratios have been used as an indicator of natural against anthropogenic sources of uranium. The results show that levels of {sup 238}U activity concentrations in soils above 100 Bq.kg{sup -1} can be considered a 'tracer' of the presence of DU in soils. The results also indicate that detectable ground surface contamination by DU is limited to areas within a few metres from localised points of concentrated contamination caused by penetrator impacts. Vertical distribution of DU along the soil profile is measurable up to a depth of 10-20 cm. This latter aspect is of particular relevance for the potential risk of future contamination of groundwater. (author)

  2. Disruption of Interleukin-1β Autocrine Signaling Rescues Complex I Activity and Improves ROS Levels in Immortalized Epithelial Cells with Impaired Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Function

    OpenAIRE

    Clauzure, Mariángeles; Valdivieso, Angel G.; Massip Copiz, María M.; Schulman, Gustavo; Teiber, María Luz; Santa-Coloma, Tomás A.

    2014-01-01

    Patients with cystic fibrosis (CF) have elevated concentration of cytokines in sputum and a general inflammatory condition. In addition, CF cells in culture produce diverse cytokines in excess, including IL-1β. We have previously shown that IL-1β, at low doses (∼30 pM), can stimulate the expression of CFTR in T84 colon carcinoma cells, through NF-κB signaling. However, at higher doses (>2.5 ng/ml, ∼150 pM), IL-1β inhibit CFTR mRNA expression. On the other hand, by using differential display, ...

  3. B-cell depletion in the treatment of lupus nephritis.

    Science.gov (United States)

    Gregersen, Jon W; Jayne, David R W

    2012-09-01

    Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that is clinically heterogeneous and affects multiple organs. Lupus nephritis is the most frequent severe manifestation of SLE. Conventional immunosuppressive therapy has increased the life expectancy of patients diagnosed with lupus nephritis, but only 70-80% of patients respond to this treatment and its adverse effects are considerable. B cells are central to the pathogenesis of SLE and are, therefore, an attractive therapeutic target. B-cell depletion has been used successfully to treat other autoimmune diseases, such as rheumatoid arthritis and antineutrophil cytoplasmic antibody-associated vasculitis, and many case reports and small nonrandomized trials of B-cell-depleting agents in patients with lupus nephritis have reported positive results. By contrast, two large placebo-controlled trials designed to investigate the efficacy of the B-cell-depleting agents rituximab and ocrelizumab as a treatment for lupus nephritis, failed to meet their primary efficacy end points (LUNAR and BELONG, respectively). This Review discusses the current evidence on the use of B-cell depletion in the treatment of lupus nephritis, which is derived from case studies and clinical trials including a total of over 800 patients. PMID:22801948

  4. DURABILITY OF DEPLETED URANIUM AGGREGATES (DUAGG) IN DUCRETE SHIELDING APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Mattus, Catherine H.; Dole, Leslie R.

    2003-02-27

    The depleted uranium (DU) inventory in the United States exceeds 500,000 metric tonnes. To evaluate the possibilities for reuse of this stockpile of DU, the U.S. Department of Energy (DOE) has created a research and development program to address the disposition of its DU(1). One potential use for this stockpile material is in the fabrication of nuclear shielding casks for the storage, transport, and disposal of spent nuclear fuels. The use of the DU-based shielding would reduce the size and weight of the casks while allowing a level of protection from neutrons and gamma rays comparable to that afforded by steel and concrete. DUAGG (depleted uranium aggregate) is formed of depleted uranium dioxide (DUO2) sintered with a synthetic-basalt-based binder. This study was designed to investigate possible deleterious reactions that could occur between the cement paste and the DUAGG. After 13 months of exposure to a cement pore solution, no deleterious expansive mineral phases were observed to form either with the DUO2 or with the simulated-basalt sintering phases. In the early stages of these exposure tests, Oak Ridge National Laboratory preliminary results confirm that the surface reactions of this aggregate proceed more slowly than expected. This finding may indicate that DUAGG/DUCRETE (depleted uranium concrete) casks could have service lives sufficient to meet the projected needs of DOE and the commercial nuclear power industry.

  5. Monte Carlo simulation in UWB1 depletion code

    International Nuclear Information System (INIS)

    UWB1 depletion code is being developed as a fast computational tool for the study of burnable absorbers in the University of West Bohemia in Pilsen, Czech Republic. In order to achieve higher precision, the newly developed code was extended by adding a Monte Carlo solver. Research of fuel depletion aims at development and introduction of advanced types of burnable absorbers in nuclear fuel. Burnable absorbers (BA) allow the compensation of the initial reactivity excess of nuclear fuel and result in an increase of fuel cycles lengths with higher enriched fuels. The paper describes the depletion calculations of VVER nuclear fuel doped with rare earth oxides as burnable absorber based on performed depletion calculations, rare earth oxides are divided into two equally numerous groups, suitable burnable absorbers and poisoning absorbers. According to residual poisoning and BA reactivity worth, rare earth oxides marked as suitable burnable absorbers are Nd, Sm, Eu, Gd, Dy, Ho and Er, while poisoning absorbers include Sc, La, Lu, Y, Ce, Pr and Tb. The presentation slides have been added to the article

  6. Engineering analysis for disposal of depleted uranium tetrafluoride (UF4)

    International Nuclear Information System (INIS)

    This report presents and evaluates options for disposing of depleted uranium in the chemical form of uranium tetrafluoride (UF4). Two depleted uranium inventories are considered. One results from the original U.S. Department of Energy (DOE) inventory of 560,000 metric tons (te) of depleted uranium hexafluoride (UF6); the other inventory is the original DOE inventory augmented by 145,000 te of depleted UF6 from the United States Enrichment Corporation. Preconceptual designs are included for three disposal options: disposal in a vault, disposal in an engineered trench, and disposal in a deep mine cavity. The disposal container is taken to be either a 30-gallon drum or a 55-gallon drum. Descriptions of the facilities associated with the three disposal options are provided. Staffing estimates for the construction and operation of the facilities are also provided. Wastes and emissions from the facilities during construction, operation, and maintenance have been estimated. Parametric studies have also been performed on the basis of 25% and 50% of the original inventory

  7. A method to estimate groundwater depletion from confining layers

    Science.gov (United States)

    Konikow, L.F.; Neuzil, C.E.

    2007-01-01

    Although depletion of storage in low-permeability confining layers is the source of much of the groundwater produced from many confined aquifer systems, it is all too frequently overlooked or ignored. This makes effective management of groundwater resources difficult by masking how much water has been derived from storage and, in some cases, the total amount of water that has been extracted from an aquifer system. Analyzing confining layer storage is viewed as troublesome because of the additional computational burden and because the hydraulic properties of confining layers are poorly known. In this paper we propose a simplified method for computing estimates of confining layer depletion, as well as procedures for approximating confining layer hydraulic conductivity (K) and specific storage (Ss) using geologic information. The latter makes the technique useful in developing countries and other settings where minimal data are available or when scoping calculations are needed. As such, our approach may be helpful for estimating the global transfer of groundwater to surface water. A test of the method on a synthetic system suggests that the computational errors will generally be small. Larger errors will probably result from inaccuracy in confining layer property estimates, but these may be no greater than errors in more sophisticated analyses. The technique is demonstrated by application to two aquifer systems: the Dakota artesian aquifer system in South Dakota and the coastal plain aquifer system in Virginia. In both cases, depletion from confining layers was substantially larger than depletion from the aquifers.

  8. Development of depletion perturbation theory for a reactor nodal code

    International Nuclear Information System (INIS)

    A generalized depletion perturbation (DPT) theory formulation for light water reactor (LWR) depletion problems is developed and implemented into the three-dimensional LWR nodal code SIMULATE. This development applies the principles of the original derivation by M.L. Williams to the nodal equations solved by SIMULATE. The present formulation is first described in detail, and the nodal coupling methodology in SIMULATE is used to determine partial derivatives of the coupling coefficients. The modifications to the original code and the new DPT options available to the user are discussed. Finally, the accuracy and the applicability of the new DPT capability to LWR design analysis are examined for several LWR depletion test cases. The cases range from simple static cases to a realistic PWR model for an entire fuel cycle. Responses of interest included K/sub eff/, nodal peaking, and peak nodal exposure. The nonlinear behavior of responses with respect to perturbations of the various types of cross sections was also investigated. The time-dependence of the sensitivity coefficients for different responses was examined and compared. Comparison of DPT results for these examples to direct calculations reveals the limited applicability of depletion perturbation theory to LWR design calculations at the present. The reasons for these restrictions are discussed, and several methods which might improve the computational accuracy of DPT are proposed for future research

  9. The health hazards of depleted uranium munitions. Part 1

    International Nuclear Information System (INIS)

    Depleted uranium is a toxic and weakly radioactive metal used for a variety of purposes. Perhaps its most controversial use is in battlefield munitions, where it can be widely dispersed in the form of fine particles and shrapnel that may enter the bodies of combatants and others through inhalation, ingestion or wounding. It is a matter of legitimate public concern whether the use of this material in this way could create unacceptable health hazards or damage to the environment. The objective of our study has been to provide the best scientific understanding of the ways in which the material may be distributed, how it may be taken up by humans, and the potential implications for health. For politicians, any hazards to health have to be balanced against the military advantages that the use of these munitions confers. We have not tried to reach a judgment on these political issues, but we believe that a better scientific understanding of the extent of the hazards will make it easier for these wider questions to be addressed in a more objective way. This report is the first of two, and addresses the likely levels of exposure to depleted uranium, the resulting radiological risks, and the lessons to be learned from epidemiological studies. Our second report will address toxicological risks and environmental issues. So far, we conclude that risks from radiation are low for most soldiers on the battlefield, and for civilians who later return to the area. However, there are uncertainties about the maximal levels of exposure to depleted uranium on the battlefield, and there may be circumstances in which a few soldiers are exposed to levels of depleted uranium that result in a significant risk to health. Further studies are needed to determine the levels of exposure to depleted uranium that might occur on the battlefield and to judge whether such higher risks are likely to occur in practice

  10. Iron depletion enhances the effect of sorafenib in hepatocarcinoma.

    Science.gov (United States)

    Urano, Shinichi; Ohara, Toshiaki; Noma, Kazuhiro; Katsube, Ryoichi; Ninomiya, Takayuki; Tomono, Yasuko; Tazawa, Hiroshi; Kagawa, Shunsuke; Shirakawa, Yasuhiro; Kimura, Fumiaki; Nouso, Kazuhiro; Matsukawa, Akihiro; Yamamoto, Kazuhide; Fujiwara, Toshiyoshi

    2016-06-01

    ABSTACT Human hepatocellular carcinoma (HCC) is known to have a poor prognosis. Sorafenib, a molecular targeted drug, is most commonly used for HCC treatment. However, its effect on HCC is limited in clinical use and therefore new strategies regarding sorafenib treatment are required. Iron overload is known to be associated with progression of chronic hepatitis and increased risk of HCC. We previously reported that iron depletion inhibited cancer cell proliferation and conversely induced angiogenesis. Indeed iron depletion therapy including iron chelator needs to be combined with anti-angiogenic drug for its anti-cancer effect. Since sorafenib has an anti-angiogenic effect by its inhibitory targeting VEGFR, we hypothesized that sorafenib could complement the anti-cancer effect of iron depletion. We retrospectively analyzed the relationship between the efficacy of sorafenib and serum iron-related markers in clinical HCC patients. In clinical cases, overall survival was prolonged in total iron binding capacity (TIBC) high- and ferritin low-patients. This result suggested that the low iron-pooled patients, who could have a potential of more angiogenic properties in/around HCC tumors, could be adequate for sorafenib treatment. We determined the effect of sorafenib (Nexavar®) and/or deferasirox (EXJADE®) on cancer cell viability, and on cell signaling of human hepatocarcinoma HepG2 and HLE cells. Both iron depletion by deferasirox and sorafenib revealed insufficient cytotoxic effect by each monotherapy, however, on the basis of increased angiogenesis by iron depletion, the addition of deferasirox enhanced anti-proliferative effect of sorafenib. Deferasirox was confirmed to increase vascular endothelial growth factor (VEGF) secretion into cellular supernatants by ELISA analysis. In in vivo study sorafenib combined with deferasirox also enhanced sorafenib-induced apoptosis. These results suggested that sorafenib combined with deferasirox could be a novel combination

  11. Evaluation of three high abundance protein depletion kits for umbilical cord serum proteomics

    Directory of Open Access Journals (Sweden)

    Nie Jing

    2011-05-01

    Full Text Available Abstract Background High abundance protein depletion is a major challenge in the study of serum/plasma proteomics. Prior to this study, most commercially available kits for depletion of highly abundant proteins had only been tested and evaluated in adult serum/plasma, while the depletion efficiency on umbilical cord serum/plasma had not been clarified. Structural differences between some adult and fetal proteins (such as albumin make it likely that depletion approaches for adult and umbilical cord serum/plasma will be variable. Therefore, the primary purposes of the present study are to investigate the efficiencies of several commonly-used commercial kits during high abundance protein depletion from umbilical cord serum and to determine which kit yields the most effective and reproducible results for further proteomics research on umbilical cord serum. Results The immunoaffinity based kits (PROTIA-Sigma and 5185-Agilent displayed higher depletion efficiency than the immobilized dye based kit (PROTBA-Sigma in umbilical cord serum samples. Both the PROTIA-Sigma and 5185-Agilent kit maintained high depletion efficiency when used three consecutive times. Depletion by the PROTIA-Sigma Kit improved 2DE gel quality by reducing smeared bands produced by the presence of high abundance proteins and increasing the intensity of other protein spots. During image analysis using the identical detection parameters, 411 ± 18 spots were detected in crude serum gels, while 757 ± 43 spots were detected in depleted serum gels. Eight spots unique to depleted serum gels were identified by MALDI- TOF/TOF MS, seven of which were low abundance proteins. Conclusions The immunoaffinity based kits exceeded the immobilized dye based kit in high abundance protein depletion of umbilical cord serum samples and dramatically improved 2DE gel quality for detection of trace biomarkers.

  12. MCOR - Monte Carlo depletion code for reference LWR calculations

    International Nuclear Information System (INIS)

    Research highlights: → Introduction of a reference Monte Carlo based depletion code with extended capabilities. → Verification and validation results for MCOR. → Utilization of MCOR for benchmarking deterministic lattice physics (spectral) codes. - Abstract: The MCOR (MCnp-kORigen) code system is a Monte Carlo based depletion system for reference fuel assembly and core calculations. The MCOR code is designed as an interfacing code that provides depletion capability to the LANL Monte Carlo code by coupling two codes: MCNP5 with the AREVA NP depletion code, KORIGEN. The physical quality of both codes is unchanged. The MCOR code system has been maintained and continuously enhanced since it was initially developed and validated. The verification of the coupling was made by evaluating the MCOR code against similar sophisticated code systems like MONTEBURNS, OCTOPUS and TRIPOLI-PEPIN. After its validation, the MCOR code has been further improved with important features. The MCOR code presents several valuable capabilities such as: (a) a predictor-corrector depletion algorithm, (b) utilization of KORIGEN as the depletion module, (c) individual depletion calculation of each burnup zone (no burnup zone grouping is required, which is particularly important for the modeling of gadolinium rings), and (d) on-line burnup cross-section generation by the Monte Carlo calculation for 88 isotopes and usage of the KORIGEN libraries for PWR and BWR typical spectra for the remaining isotopes. Besides the just mentioned capabilities, the MCOR code newest enhancements focus on the possibility of executing the MCNP5 calculation in sequential or parallel mode, a user-friendly automatic re-start capability, a modification of the burnup step size evaluation, and a post-processor and test-matrix, just to name the most important. The article describes the capabilities of the MCOR code system; from its design and development to its latest improvements and further ameliorations

  13. MCOR - Monte Carlo depletion code for reference LWR calculations

    Energy Technology Data Exchange (ETDEWEB)

    Puente Espel, Federico, E-mail: fup104@psu.edu [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States); Tippayakul, Chanatip, E-mail: cut110@psu.edu [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States); Ivanov, Kostadin, E-mail: kni1@psu.edu [Department of Mechanical and Nuclear Engineering, Pennsylvania State University (United States); Misu, Stefan, E-mail: Stefan.Misu@areva.com [AREVA, AREVA NP GmbH, Erlangen (Germany)

    2011-04-15

    Research highlights: > Introduction of a reference Monte Carlo based depletion code with extended capabilities. > Verification and validation results for MCOR. > Utilization of MCOR for benchmarking deterministic lattice physics (spectral) codes. - Abstract: The MCOR (MCnp-kORigen) code system is a Monte Carlo based depletion system for reference fuel assembly and core calculations. The MCOR code is designed as an interfacing code that provides depletion capability to the LANL Monte Carlo code by coupling two codes: MCNP5 with the AREVA NP depletion code, KORIGEN. The physical quality of both codes is unchanged. The MCOR code system has been maintained and continuously enhanced since it was initially developed and validated. The verification of the coupling was made by evaluating the MCOR code against similar sophisticated code systems like MONTEBURNS, OCTOPUS and TRIPOLI-PEPIN. After its validation, the MCOR code has been further improved with important features. The MCOR code presents several valuable capabilities such as: (a) a predictor-corrector depletion algorithm, (b) utilization of KORIGEN as the depletion module, (c) individual depletion calculation of each burnup zone (no burnup zone grouping is required, which is particularly important for the modeling of gadolinium rings), and (d) on-line burnup cross-section generation by the Monte Carlo calculation for 88 isotopes and usage of the KORIGEN libraries for PWR and BWR typical spectra for the remaining isotopes. Besides the just mentioned capabilities, the MCOR code newest enhancements focus on the possibility of executing the MCNP5 calculation in sequential or parallel mode, a user-friendly automatic re-start capability, a modification of the burnup step size evaluation, and a post-processor and test-matrix, just to name the most important. The article describes the capabilities of the MCOR code system; from its design and development to its latest improvements and further ameliorations. Additionally

  14. Global Storm-Time Depletion of the Outer Electron Belt

    Science.gov (United States)

    Ukhorskiy, A. Y.; Sitnov, M. I.; Millan, R. M.; Kress, B. T.; Fennell, J. F.

    2014-12-01

    The outer radiation belt consists of relativistic (≳0.5 MeV) electrons trapped on closed trajectories around Earth where its magnetic field is nearly dipolar. During increased geomagnetic activity electron intensities in the belt can vary by orders of magnitude at different spatial and temporal scale. The main phase of geomagnetic storms often produces deep depletions of electron intensities over broad regions of the outer belt. Previous studies identified three possible processes that can contribute to the depletions: fully adiabatic inflation of electron drift orbits caused the ring current growth, electron loss into the atmosphere due to pitch-angle scattering by plasma waves (e.g., EMIC and whistler waves), and electron escape through the magnetopause boundary. In this paper we investigate the relative importance of the magnetopause losses to the rapid depletion of the outer belt observed at the Van Allen Probes spacecraft during the main phase of March 17, 2013 storm. The intensities of > 1 MeV electrons were depleted by more that an order of magnitude over the entire radial extent of the belt in less than 6 hours after the sudden storm commencement. For the analysis we used three-dimensional test-particle simulations of global evolution of the outer belt in the Tsyganenko-Sitnov (TS07D) magnetic field model with the inductive electric field. The comparison of the simulation results with electron measurements from the MagEIS experiment shows that the magnetopause losses in the model accounts for most of the observed depletion. The individual electron motion the process is non-adiabatic; the third invariant is violated by global variations of the inner magnetospheric fields caused by the magnetopause compressions and the buildup of ring current, while the second invariant is violated at drift orbit bifurcations. The analysis shows that the observed deep depletion of radiation belt intensities is enabled by the change in the global configuration of magnetic

  15. Improved radiochemical assay analyses using TRITON depletion sequences in SCALE

    International Nuclear Information System (INIS)

    With the release of TRITON in SCALE 5.0, Oak Ridge National Laboratory has made available a rigorous two-dimensional (2D) depletion sequence based on the arbitrary-geometry 2D discrete ordinates transport solver NEWT. TRITON has recently been further enhanced by the addition of depletion sequences that use KENO V.a and KENO-VI for three-dimensional (3D) transport solutions. The Monte Carlo-based depletion sequences add stochastic uncertainty issues to the solution, but also provide a means to perform direct 3D depletion that can capture the effect of leakage near the ends of fuel assemblies. Additionally, improved resonance processing capabilities are available to TRITON using CENTRM. CENTRM provides lattice-weighted cross sections using a continuous energy solution that directly treats the resonance overlap effects that become more important in high-burnup fuel. And beginning with the release of SCALE 5.1 in the summer of 2006, point data and fine-structure multigroup libraries derived from ENDF/B-VI evaluations will be available. The combination of rigorous 2D and 3D capabilities with improved cross section processing capabilities and data will provide a powerful and accurate means for the characterization of spent fuel, making it possible to analyze a broad range of assembly designs and assay data. This in turn will reduce biases and uncertainties associated with the preduction of spent fuel isotopic compositions. This paper describes advanced capabilities of the TRITON sequence for depletion calculations and the results of analyses performed to date for radiochemical assay data. (author)

  16. Depletion of compounds from thin oil films in seawater

    International Nuclear Information System (INIS)

    When oil is spilled on water, the oil compounds distribute between droplets and water-soluble phases in the water column. Some small organic acids, phenols, BTEX, and aromatic compounds will dissolve completely, but larger polycyclic aromatic hydrocarbons (PAH) and alkanes will remain in the droplet fraction. The biodegradation of droplets occurs at the oil-water interface. A method for immobilizing the oil films onto hydrophobic surfaces was developed in order to obtain a stable oil surface during the biodegradation period. A test system was also established to determine the depletion of oil compounds from the oil phase, including both abiotic and biotic processes. Three North Sea oils were used in the study. Two were paraffinic oils rich in n-alkanes and aromatic compounds, and one was asphalthenic which was richer in branched alkanes and PAH. The biodegradation period was 2 months at 13 degrees C. Samples from the water and thin film on the fabric was analyzed for carbon 10 and carbon 36 by gas chromatography-flame ionization detection. Semi-volatile organic compounds were analyzed using gas chromatography-mass spectrometry. Results indicated that the depletion process for alkanes was completely caused by biodegradation, while aromatic compounds were depleted by abiotic dissolution as well as by biodegradation. The system has potential for determining oil depletion processes under controlled surface-to-volume conditions, such as thin oil films and dispersed oil droplets. In addition, the system can be used to determine the depletion process in flow-through systems. 13 refs., 3 tabs., 9 figs

  17. Coarse-grained molecular dynamics simulations of depletion-induced interactions for soft matter systems

    Energy Technology Data Exchange (ETDEWEB)

    Shendruk, Tyler N., E-mail: tyler.shendruk@physics.ox.ac.uk [The Rudolf Peierls Centre for Theoretical Physics, Department of Physics, Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Bertrand, Martin; Harden, James L.; Slater, Gary W. [Department of Physics, University of Ottawa, 150 Louis-Pasteur, Ottawa, Ontario K1N 6N5 (Canada); Haan, Hendrick W. de [Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe St. North, Oshawa, Ontario L1H 7K4 (Canada)

    2014-12-28

    Given the ubiquity of depletion effects in biological and other soft matter systems, it is desirable to have coarse-grained Molecular Dynamics (MD) simulation approaches appropriate for the study of complex systems. This paper examines the use of two common truncated Lennard-Jones (Weeks-Chandler-Andersen (WCA)) potentials to describe a pair of colloidal particles in a thermal bath of depletants. The shifted-WCA model is the steeper of the two repulsive potentials considered, while the combinatorial-WCA model is the softer. It is found that the depletion-induced well depth for the combinatorial-WCA model is significantly deeper than the shifted-WCA model because the resulting overlap of the colloids yields extra accessible volume for depletants. For both shifted- and combinatorial-WCA simulations, the second virial coefficients and pair potentials between colloids are demonstrated to be well approximated by the Morphometric Thermodynamics (MT) model. This agreement suggests that the presence of depletants can be accurately modelled in MD simulations by implicitly including them through simple, analytical MT forms for depletion-induced interactions. Although both WCA potentials are found to be effective generic coarse-grained simulation approaches for studying depletion effects in complicated soft matter systems, combinatorial-WCA is the more efficient approach as depletion effects are enhanced at lower depletant densities. The findings indicate that for soft matter systems that are better modelled by potentials with some compressibility, predictions from hard-sphere systems could greatly underestimate the magnitude of depletion effects at a given depletant density.

  18. Development of ARMS PCR tests for detection of common CFTR gene mutations

    Directory of Open Access Journals (Sweden)

    Livshits L. A.

    2010-09-01

    Full Text Available Aim. To develop diagnostic assays, based on the amplification refractory mutation system (ARMS principle, for detection of common mutations in the CFTR gene using two approaches: standard PCR with further gel-electrophoresis and Real-Time PCR with SYBR Green. Materials. For this study we have chosen the following mutations: dF508, W1282X, R117H, 621 + 1G > T, 2143delT with the frequencies in Ukraine: dF508 – 43.3 %; 2143delT – 1.38 %; W1282X – 1.1 %; R117H, 621 + 1G > T – T, 2143delT mutations. To validate the developed assays we have analyzed control DNA samples with the following mutations: W1282X (n = 3, R117H (n = 2, 621 + 1G > T (n = 1, 2143delT (n = = 1. For validation of the dF508 assay we have analyzed 100 heterozygous carriers and 50 homozygous carriers. We have analyzed 48 patients with cystic fibrosis, in which only one mutation was previously detected in combination with unknown mutant variant, using the developed ARMS assay for the 2143delT mutation, and detected 4 heterozygous carriers. No differences were observed in comparison with the standard protocols. Conclusions. It was shown that ARMS is a reliable, rapid and inexpensive method, and the developed assays can be applied in the standard PCR protocol with further gel-electrophoresis as well as using Real-Time PCR with SYBR Green for the molecular genetic diagnostics of cystic fibrosis.

  19. Depletion of cellular poly (A) binding protein prevents protein synthesis and leads to apoptosis in HeLa cells

    International Nuclear Information System (INIS)

    Highlights: → Depletion of cellular PABP level arrests mRNA translation in HeLa cells. → PABP knock down leads to apoptotic cell death. → PABP depletion does not affect transcription. → PABP depletion does not lead to nuclear accumulation of mRNA. -- Abstract: The cytoplasmic poly (A) binding protein (PABP) is important in mRNA translation and stability. In yeast, depletion of PABP leads to translation arrest. Similarly, the PABP gene in Drosophila is important for proper development. It is however uncertain, whether mammalian PABP is essential for mRNA translation. Here we showed the effect of PABP depletion on mRNA metabolism in HeLa cells by using a small interfering RNA. Our results suggest that depletion of PABP prevents protein synthesis and consequently leads to cell death through apoptosis. Interestingly, no detectable effect of PABP depletion on transcription, transport and stability of mRNA was observed.

  20. Depletion of cellular poly (A) binding protein prevents protein synthesis and leads to apoptosis in HeLa cells

    Energy Technology Data Exchange (ETDEWEB)

    Thangima Zannat, Mst.; Bhattacharjee, Rumpa B. [Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G2W1 (Canada); Bag, Jnanankur, E-mail: jbag@uoguelph.ca [Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada N1G2W1 (Canada)

    2011-05-13

    Highlights: {yields} Depletion of cellular PABP level arrests mRNA translation in HeLa cells. {yields} PABP knock down leads to apoptotic cell death. {yields} PABP depletion does not affect transcription. {yields} PABP depletion does not lead to nuclear accumulation of mRNA. -- Abstract: The cytoplasmic poly (A) binding protein (PABP) is important in mRNA translation and stability. In yeast, depletion of PABP leads to translation arrest. Similarly, the PABP gene in Drosophila is important for proper development. It is however uncertain, whether mammalian PABP is essential for mRNA translation. Here we showed the effect of PABP depletion on mRNA metabolism in HeLa cells by using a small interfering RNA. Our results suggest that depletion of PABP prevents protein synthesis and consequently leads to cell death through apoptosis. Interestingly, no detectable effect of PABP depletion on transcription, transport and stability of mRNA was observed.

  1. Equatorial plasma depletions observed by the DMSP F13 satellite near dawn during geomagnetic disturbances in a solar minimum

    Science.gov (United States)

    Kim, V. P.; Min, K. W.; Hegai, V. V.

    2015-01-01

    We report on in situ measurements of equatorial plasma depletions in the dawn sector from the DMSP F13 satellite during magnetic disturbances which occurred within the solar minimum period of 1995-1996. Examples are given when DMSP F13 observed prominent pre-sunrise depletions associated with weak magnetic disturbances, while the most severe magnetic storms of the period showed only small amplitude depletions of plasma density. Our results indicate that the depletions were observed within about two third of the magnetically perturbed days with the negative maximum excursions of SYM-H less than -40 nT at any season and at various longitudes. Commonly, the depletions appear following the negative SYM-H peaks in the recovery phase of the magnetic disturbances. We discuss the roles of corotating evening depletions and near-dawn effects of the prompt penetration overshielding and the disturbance dynamo eastward electric fields as sources for the reported depletions.

  2. Ozone depletion and chlorine loading potentials

    Science.gov (United States)

    Pyle, John A.; Wuebbles, Donald J.; Solomon, Susan; Zvenigorodsky, Sergei; Connell, Peter; Ko, Malcolm K. W.; Fisher, Donald A.; Stordal, Frode; Weisenstein, Debra

    1991-01-01

    The recognition of the roles of chlorine and bromine compounds in ozone depletion has led to the regulation or their source gases. Some source gases are expected to be more damaging to the ozone layer than others, so that scientific guidance regarding their relative impacts is needed for regulatory purposes. Parameters used for this purpose include the steady-state and time-dependent chlorine loading potential (CLP) and the ozone depletion potential (ODP). Chlorine loading potentials depend upon the estimated value and accuracy of atmospheric lifetimes and are subject to significant (approximately 20-50 percent) uncertainties for many gases. Ozone depletion potentials depend on the same factors, as well as the evaluation of the release of reactive chlorine and bromine from each source gas and corresponding ozone destruction within the stratosphere.

  3. Department of Energy depleted uranium recycle

    International Nuclear Information System (INIS)

    With its strategic supply of depleted uranium, the Department of Energy is studying reuse of the material in nuclear radiation shields, military hardware, and commercial applications. the study is expected to warrant a more detailed uranium recycle plan which would include consideration of a demonstration program and a program implementation decision. Such a program, if implemented, would become the largest nuclear material recycle program in the history of the Department of Energy. The bulk of the current inventory of depleted uranium is stored in 14-ton cylinders in the form of solid uranium hexafluoride (UF6). The radioactive 235U content has been reduced to a concentration of 0.2% to 0.4%. Present estimates indicate there are about 55,000 UF6-filled cylinders in inventory and planned operations will provide another 2,500 cylinders of depleted uranium each year. The United States government, under the auspices of the Department of Energy, considers the depleted uranium a highly-refined strategic resource of significant value. A possible utilization of a large portion of the depleted uranium inventory is as radiation shielding for spent reactor fuels and high-level radioactive waste. To this end, the Department of Energy study to-date has included a preliminary technical review to ascertain DOE chemical forms useful for commercial products. The presentation summarized the information including preliminary cost estimates. The status of commercial uranium processing is discussed. With a shrinking market, the number of chemical conversion and fabrication plants is reduced; however, the commercial capability does exist for chemical conversion of the UF6 to the metal form and for the fabrication of uranium radiation shields and other uranium products. Department of Energy facilities no longer possess a capability for depleted uranium chemical conversion

  4. Gammaspectrometric determination of depleted uranium in soil

    International Nuclear Information System (INIS)

    Full text: Three years of monitoring the content of natural radionuclides as well as radionuclides of artificial origin in all samples in the south part of the Republic of Serbia and Montenegro indicated that there was widespread, low-level contamination by depleted uranium at this region. High activity of depleted uranium was found in the soil samples taken at the points where the penetrators were found. We used high resolution gamma spectrometry measurements, because of their simplicity and accuracy. Aims of the control were to asses the increase of radioactivity above the natural levels in the immediate and near vicinity of the bomb craters, to asses the corresponding effect of changed natural radioactivity on the health of the population living in these places and finding unexploded depleted uranium bullets. The collected soil samples were cleaned of plants and stones, dried at 105 deg. C - 110 deg. C till constant weight for 24-48 h. After this, the samples were ground, sieved, and measure in cylindrical geometry. Gamma activity was determined by gamma spectrometry measurements using HP Ge detector (ORTEC), with relative efficiency of 25% and energy resolution of 1.85 keV (1332.5 keV 60Co). The analyser system conducts a peak search, energy assignment, quantification and nuclide identification in acquired spectra. Time of measurement varied from 60000 s to 250000 s. Depleted uranium was found in the soil samples from Vranje region and cape Arza (Montenegro). There are four fenced areas in Vranje region (Pljackovica, Bratoselce, Borovac and Reljan) and one in the Montenegro (cape Arza) where we have found depleted uranium penetrators. The 238U and 235U specific activities and their isotopic composition correspond to depleted uranium (238U/235U ratio from 35 to 77). (author)

  5. Rhodium in-core detector sensitivity depletion, cycles 2 to 4. Interim report

    International Nuclear Information System (INIS)

    Sensitivity depletion of two rhodium (Rh) self-powered neutron detectors (SPNDs) has been measured since July 1976 at the Oconee 2 pressurized water reactor (PWR). The detectors were positioned inside the reactor core throughout the measurement period. Depletion has been determined as a function of electric charge expended (released) by each detector. The goal of the project is the empirical definition of the depletion characteristics over the operating life-time of the Rh detector. Results to data show that the sensitivity depletion rate of the Rh detector in the PWR is highly linear with charge released from the detector. In contrast to preliminary observations reported earlier, there appears to be no effect on the depletion rate that is traceable to the beginning-of-cycle burnup of the fuel assembly in which the Rh detectors are located

  6. Ozone depletion in the stratosphere: extent, causes and consequences

    International Nuclear Information System (INIS)

    According to present knowledge the causes of depleting the stratospheric ozone layer are exclusively anthropogenic. CFC's and (to smaller extent) halons enter the chain mechanisms of photochemical ozone loss with the result that its steady state concentration is reduced. Ozone depletion in the stratosphere has a number of consequences for the chemistry and the dynamics of the stratosphere. More severe, however, is its potential consequence to humans, animals and plants due to an increase in UV-B intensity near the surface. Current model studies predict, that the observed ozone change in mid-latitudes of the northern hemisphere should have resulted in a change of the UV-B-dose by as much as +7%/decade. (orig./DG)

  7. Ionospheric heating, upwelling, and depletions in auroral current systems

    Science.gov (United States)

    Zettergren, M. D.; Semeter, J. L.

    2010-12-01

    This research investigates aspects of ionospheric dynamics relevant to magnetosphere-ionosphere coupling in auroral arc current systems. Auroral electric fields and particle precipitation deposit energy in the ionosphere, often resulting in enhanced ion or electron temperatures. This heating has a wide variety of consequences for the ionosphere. High ion temperatures alter chemical balance in the lower F-region, resulting in conversion to a molecular ion plasma, faster recombination, and plasma depletions. Pressure enhancements resulting from both ion and electron heating are capable of generating intense ion upflows. Ion upflow and depletion processes redistribute and structure the auroral plasma in ways that are likely of consequence to wave coupling of the magnetosphere and ionosphere. These implications are examined through the use of a fluid-kinetic model of the auroral ionosphere and new incoherent scatter radar data analysis techniques. Results indicate that enhanced recombination of molecular ions in auroral downward current regions may work in concert with well-known electrodynamic depletion processes, in the F-region ionosphere. Furthermore, ionospheric upflows in auroral upward and downward current regions may be quite different in terms of intensity and types of upflowing ions.

  8. The Chemistry and Toxicology of Depleted Uranium

    OpenAIRE

    Katz, Sidney A.

    2014-01-01

    Natural uranium is comprised of three radioactive isotopes: 238U, 235U, and 234U. Depleted uranium (DU) is a byproduct of the processes for the enrichment of the naturally occurring 235U isotope. The world wide stock pile contains some 1½ million tons of depleted uranium. Some of it has been used to dilute weapons grade uranium (~90% 235U) down to reactor grade uranium (~5% 235U), and some of it has been used for heavy tank armor and for the fabrication of armor-piercing bullets and missiles....

  9. Toxicological issues after depleted uranium weapons attacked

    International Nuclear Information System (INIS)

    Depleted Uranium (DU) is a byproduct of the uranium enrichment for producing nuclear reactor or nuclear weapon. DU is used in the military as an armor-piercing projectile due to its hardness, strength, and density. A lot of DU weapons were fired in the Gulf War, and bring about critical environmental and internal contamination. Therefore, DU becomes suddenly a hot issue. Some toxicological problems after DU weapons attacked have been reviewed, which include features of internal DU contamination. Hazard of wound contamination and inhalation with insoluble uranium, and other urgent toxicological issues. The healthy effects of implanted with depleted uranium pellets were illustrated in particular

  10. Nanoparticles that deliver triplex-forming peptide nucleic acid molecules correct F508del CFTR in airway epithelium.

    Science.gov (United States)

    McNeer, Nicole Ali; Anandalingam, Kavitha; Fields, Rachel J; Caputo, Christina; Kopic, Sascha; Gupta, Anisha; Quijano, Elias; Polikoff, Lee; Kong, Yong; Bahal, Raman; Geibel, John P; Glazer, Peter M; Saltzman, W Mark; Egan, Marie E

    2015-01-01

    Cystic fibrosis (CF) is a lethal genetic disorder most commonly caused by the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. It is not readily amenable to gene therapy because of its systemic nature and challenges including in vivo gene delivery and transient gene expression. Here we use triplex-forming peptide nucleic acids and donor DNA in biodegradable polymer nanoparticles to correct F508del. We confirm modification with sequencing and a functional chloride efflux assay. In vitro correction of chloride efflux occurs in up to 25% of human cells. Deep-sequencing reveals negligible off-target effects in partially homologous sites. Intranasal delivery of nanoparticles in CF mice produces changes in the nasal epithelium potential difference assay, consistent with corrected CFTR function. Also, gene correction is detected in the nasal and lung tissue. This work represents facile genome engineering in vivo with oligonucleotides using a nanoparticle system to achieve clinically relevant levels of gene editing without off-target effects. PMID:25914116

  11. Deuterium depleted water. Romanian achievements and prospects

    International Nuclear Information System (INIS)

    The deuterium depleted water (DDW) is microbiologically pure distilled water with a deuterium content lower than that of natural waters which amounts to 140 - 150 ppm D/(D+H); variations depend on geographical zone and altitude. The procedure of obtaining DDW is based on isotopic separation of natural water by vacuum distillation. Isotope concentration can be chosen within 20 to 120 ppm D/(D+H). The ICSI at Rm. Valcea has patented the procedure and equipment for the production of DDW. According to the document SF-01-2002/INC-DTCI - ICSI Rm. Valcea, the product has a D/(D+H) isotope concentration of 25 ± 5. Studies and research for finding the effects and methods of application in different fields were initiated and developed in collaboration with different institutes in Romania. The following important results obtained so far could be mentioned: - absence of toxicity upon organisms; - activation of vascular reactivity; - enhancement of defence capacity of the organism through non-specific immunity activation; - increase of salmonid reproduction capacity and enhancement of the adaptability of alevins to the environmental conditions; - radioprotective effect to ionizing radiation; - maintaining meat freshness through osmotic shock; - stimulation of growth of aquatic macrophytes; - enhancement of culture plant development in certain ontogenetic stages. Mostly, the results and practical applications of the research were patented and awarded with gold medals at international invention fairs. At present, research-development programmes are undergoing to find active biological features of DDW in fighting cancer, on one hand, and its applicability as food additive of pets or performing animals, on the other hand

  12. Determination of depleted uranium in fish

    International Nuclear Information System (INIS)

    Depleted uranium (DU) is a by-product of the uranium enrichment process for nuclear fuel. According to the Commission Decision 2002/657/EC, a confirmatory method for the quantification of DU in freeze-dried fish was developed by isotope ratio dynamic reaction cell inductively coupled plasma-mass spectrometry (IR-DRC-ICP-MS). A preliminary study was performed to determine the following parameters: instrumental detection limit (IDL), isotopic ratio measurement limit (IRML), percentage of DU (PDU) in presence of natural uranium (NU) and limit of quantification (LoQDU). The analyses were carried out by means of IR-DRC-ICP-MS. Ammonia was the reaction gas used for the dynamic reaction cell. In addition, a sector field inductively coupled plasma mass spectrometer (SF-ICP-MS) was employed to calculate the within-laboratory reproducibility. For the confirmatory method the following parameters were determined: (a) trueness; (b) precision; (c) critical concentrations alpha and beta (CCα, CCβ); (d) specificity; (e) stability. Trueness was assessed by using the recovery tests. The recovery and within-laboratory reproducibility were determined by fortifying the blank digested solution of dogfish tissue: six aliquots were fortified at 1, 1.5 and 2 times the LOQDU with 25.0, 37.5 and 50.0 ng L-1 or 4.16, 6.24, 8.32 μg kg-1 with a recovery of -8.2, +9.5 and +9.6%, respectively and a within-laboratory reproducibility (three analytical run) of 15.5, 8.0 and 11.0%, respectively. The results for the decision limit and the detection capability were: CCα = 11.69 ng L-1 and CCβ = 19.8 ng L-1. The digested solutions resulted to be stable during testing time (60 days) and the method can be considered highly specific as well

  13. Structures of a minimal human CFTR first nucleotide-binding domain as a monomer, head-to-tail homodimer, and pathogenic mutant

    Energy Technology Data Exchange (ETDEWEB)

    Atwell, Shane; Brouillette, Christie G.; Conners, Kris; Emtage, Spencer; Gheyi, Tarun; Guggino, William B.; Hendle, Jorg; Hunt, John F.; Lewis, Hal A.; Lu, Frances; Protasevich, Irina I.; Rodgers, Logan A.; Romero, Rich; Wasserman, Stephen R.; Weber, Patricia C.; Wetmore, Diana; Zhang, Feiyu F.; Zhao, Xun (Cystic); (UAB); (JHU); (Columbia); (Lilly)

    2010-04-26

    Upon removal of the regulatory insert (RI), the first nucleotide binding domain (NBD1) of human cystic fibrosis transmembrane conductance regulator (CFTR) can be heterologously expressed and purified in a form that remains stable without solubilizing mutations, stabilizing agents or the regulatory extension (RE). This protein, NBD1 387-646({Delta}405-436), crystallizes as a homodimer with a head-to-tail association equivalent to the active conformation observed for NBDs from symmetric ATP transporters. The 1.7-{angstrom} resolution X-ray structure shows how ATP occupies the signature LSGGQ half-site in CFTR NBD1. The {Delta}F508 version of this protein also crystallizes as a homodimer and differs from the wild-type structure only in the vicinity of the disease-causing F508 deletion. A slightly longer construct crystallizes as a monomer. Comparisons of the homodimer structure with this and previously published monomeric structures show that the main effect of ATP binding at the signature site is to order the residues immediately preceding the signature sequence, residues 542-547, in a conformation compatible with nucleotide binding. These residues likely interact with a transmembrane domain intracellular loop in the full-length CFTR channel. The experiments described here show that removing the RI from NBD1 converts it into a well-behaved protein amenable to biophysical studies yielding deeper insights into CFTR function.

  14. The CFTR polymorphisms poly-T, TG-repeats and M470V in Chinese males with congenital bilateral absence of the vas deferens

    Institute of Scientific and Technical Information of China (English)

    Wu-Hua Ni; Lei Jiang; Qian-Jin Fei; Jian-Yuan Jin; Xu Yang; Xue-Feng Huang

    2012-01-01

    Congenital bilateral absence of the vas deferens (CBAVD) is a frequent cause of obstructive azoospermia,and mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene have also been frequently identified in patients with CBAVD.However,the distribution of the CFTR polymorphisms M470V,poly-T,TG-repeats and F508del mutation in the Chinese CBAVD population with presumed low cystic fibrosis (CF) frequency remains to be evaluated.Samples obtained from 109 Chinese infertile males with CBAVD and 104 normal controls were analyzed for the presence of CFTR (TG)m(T)n,M470V and F508del by PCR amplification followed by direct sequencing.Our study showed that the F508del mutation was not found in our patients.The 5T mutation was present with high frequency in Chinese CBAVD patients and IVS8-5T linked to either 12 or 13 TG repeats was highly prevalent among CBAVD patients (97.22% of 72 cases and 96.91% of 97 alleles with IVS8-5T).Moreover,a statistically significant relationship between TG12-5T-V470 haplotype and CBAVD was detected.This study indicated that the CFTR polymorphisms poly-T,TG-repeats and M470V might affect the process of CBAVD in the Chinese population.

  15. Radiation survey and decontamination of cape Arza from depleted uranium

    Directory of Open Access Journals (Sweden)

    Vukotić Perko

    2003-01-01

    Full Text Available In the action of NATO A-10 airplanes in 1999, the cape Arza, Serbia and Montenegro was contaminated by depleted uranium. The clean-up operations were undertaken at the site, and 242 uranium projectiles and their 49 larger fragments were removed from the cape. That is about 85% of the total number of projectiles by which Arza was contaminated. Here are described details of the applied procedures and results of the soil radioactivity measurements after decontamination.

  16. Radiation survey and decontamination of cape Arza from depleted uranium

    OpenAIRE

    Vukotić Perko; Anđelić Tomislav; Zekić Ranko; Kovačević Milojko S.; Vasić Vladimir; Savić Slobodan

    2003-01-01

    In the action of NATO A-10 airplanes in 1999, the cape Arza, Serbia and Montenegro was contaminated by depleted uranium. The clean-up operations were undertaken at the site, and 242 uranium projectiles and their 49 larger fragments were removed from the cape. That is about 85% of the total number of projectiles by which Arza was contaminated. Here are described details of the applied procedures and results of the soil radioactivity measurements after decontamination.

  17. A search for relativistic electron induced stratospheric ozone depletion

    Science.gov (United States)

    Aikin, Arthur C.

    1994-01-01

    Possible ozone changes at 1 mb associated with the time variation and precipitation of relativistic electrons are investigated by examining the NIMBUS 7 SBUV ozone data set and corresponding temperatures derived from NMC data. No ozone depletion was observed in high-latitude summer when temperature fluctuations are small. In winter more variation in ozone occurs, but large temperature changes make it difficult to identify specific ozone decreases as being the result of relativistic electron precipitation.

  18. Depleted uranium - 'the silver bullet'

    International Nuclear Information System (INIS)

    Article 35 of the Geneva protocols, signed by 150 countries in 1949 and an additional protocol signed from 1977 onwards prohibited the use of weapons that cause and inflict unnecessary injury and suffering. In the recent wars such as Bosnia, Kosovo and the Gulf War, more than 31,000 missiles were launched against enemy lines containing DU and more than 300 tonnes of DU during the Gulf War alone. DU is a radioactive and toxic element. In humans it can cause lung cancer, damage to the liver and kidney affecting the bone marrow and consequently destroying stem cells that form the white cells resulting in mutations and the long lasting effect of genetic damage

  19. Evaluating groundwater depletion as computed by a global water model

    Science.gov (United States)

    Schuh, Carina; Doell, Petra; Mueller Schmied, Hannes; Portmann, Felix

    2013-04-01

    When groundwater abstraction occurs faster than its replenishment over a long time and in a large area, the result is an overexploitation or depletion of groundwater. The problem is aggravated in areas where a growing population relies on freshwater resources for an intensive irrigation agriculture that is meant to guarantee food security. Especially in semi-arid and arid regions, the dominant use for groundwater is irrigation, reaching more than 95% of total water use. Therefore, the hot spots for groundwater depletion are the world's major irrigation areas like the central United States, north-western India and north China. Groundwater depletion presents a major threat to securing agricultural productivity and domestic water supply in these parts of the world. Besides, the environmental consequences that accompany the abstraction of groundwater are severe. Within the scientific community there is a common understanding that high-quality data on globally existing groundwater resources are deficient. In order to allow a sustainable management of the world's available groundwater resources, especially in areas under current water stress, the quantification of groundwater depletion is of high importance. WaterGAP (Water - Global Assessment and Prognosis) is a global model of water availability and water use which can serve to estimate the impact of groundwater and surface water withdrawals on groundwater storage. The new WaterGAP version 2.2a was modified to allow for an improved analysis of groundwater storage changes in semi-arid and arid regions. Now, groundwater recharge from surface water bodies is simulated in semi-arid and arid areas. Estimation of net groundwater abstractions was modified with respect of irrigation water use efficiency for groundwater and return flow fractions. In addition, irrigation consumptive use has been set to 70% of optimal irrigation consumptive use, assuming deficit irrigation to prevail in these parts of the world. Based on time

  20. Functional classification of mitochondrion-rich cells in euryhaline Mozambique tilapia (Oreochromis mossambicus) embryos, by means of triple immunofluorescence staining for Na+/K+-ATPase, Na +/K+/2Cl- cotransporter and CFTR anion channel

    Science.gov (United States)

    Hiroi, J.; McCormick, S.D.; Ohtani-Kaneko, R.; Kaneko, T.

    2005-01-01

    Mozambique tilapia Oreochromis mossambicus embryos were transferred from freshwater to seawater and vice versa, and short-term changes in the localization of three major ion transport proteins, Na+/K +-ATPase, Na+/K+/2Cl- cotransporter (NKCC) and cystic fibrosis transmembrane conductance regulator (CFTR) were examined within mitochondrion-rich cells (MRCs) in the embryonic yolk-sac membrane. Triple-color immunofluorescence staining allowed us to classify MRCs into four types: type I, showing only basolateral Na+/K +-ATPase staining; type II, basolateral Na+/K +-ATPase and apical NKCC; type III, basolateral Na+/K +-ATPase and basolateral NKCC; type IV, basolateral Na +/K+-ATPase, basolateral NKCC and apical CFTR. In freshwater, type-I, type-II and type-III cells were observed. Following transfer from freshwater to seawater, type-IV cells appeared at 12 h and showed a remarkable increase in number between 24 h and 48 h, whereas type-III cells disappeared. When transferred from seawater back to freshwater, type-IV cells decreased and disappeared at 48 h, type-III cells increased, and type-II cells, which were not found in seawater, appeared at 12 h and increased in number thereafter. Type-I cells existed consistently irrespective of salinity changes. These results suggest that type I is an immature MRC, type II is a freshwater-type ion absorptive cell, type III is a dormant type-IV cell and/or an ion absorptive cell (with a different mechanism from type II), and type IV is a seawater-type ion secretory cell. The intracellular localization of the three ion transport proteins in type-IV cells is completely consistent with a widely accepted model for ion secretion by MRCs. A new model for ion absorption is proposed based on type-II cells possessing apical NKCC.

  1. Climate Change and Oil Depletion

    International Nuclear Information System (INIS)

    Primary energy sources have progressively displaced each other and shared the supply in terms that can historically be described by a model proposed by Cesare Marchetti as a generalization of the Fisher and Pry law. So wood, coal, oil and natural gas have displaced or are displacing each other, each one following a logistic evolution until a maximum share is attained, afterwards receding in a symmetrically similar way, provided there is no exhaustion of the respective resource base, each one completing its own life cycle. On the other hand, the persistent growth of the total energy demand implies that the total amount of each one of the successive primary energy sources, required to complete its life cycle, is growing as time lapses. So it is realized that coal resources are much larger than its total life cycle demand. The same is not the case of oil, whose resource base (estimate 2000 Gb) may be smaller than the integrated prospective demand unless this starts declining steadily in the near future. However, if the rate of growth of total energy demand is persists, the amount of natural gas required to complete a similar life cycle will likely exceed its actual resource base. One faces therefore two problems: the constraint on oil availability right now and a likely, even more severe, constraint on natural gas in about twenty years time. Combustion of fossil fuels always produces CO2 emissions as well as nitrogen oxides. With the exception of natural gas, all other fuels also produce, to a variable extent, particulate matter (aerosols) and sulfur oxides. The permanent alteration of the chemical composition of the atmosphere as a result of all these emissions may affect the biogeochemical balance of the climate system. Such emissions produce recognized impacts of some sort at local and regional levels, either temporary or permanent. Whether actual impacts can be global and permanent is still under dispute; but the observed steady and simultaneous increase of the CO

  2. Application of backtracking algorithm to depletion calculations

    International Nuclear Information System (INIS)

    Based on the theory of linear chain method for analytical depletion calculations, the burn-up matrix is decoupled by the divide and conquer strategy and the linear chain with Markov characteristic is formed. The density, activity and decay heat of every nuclide in the chain can be calculated by analytical solutions. Every possible reaction path of the nuclide must be considered during the linear chain establishment process. To confirm the calculation precision and efficiency, the algorithm which can cover all the reaction paths of the nuclide and search the paths automatically according to to problem description and precision restrictions should be sought. Through analysis and comparison of several kinds of searching algorithms, the backtracking algorithm was selected to search and calculate the linear chains using Depth First Search (DFS) method. The depletion program can solve the depletion problem adaptively and with high fidelity. The solution space and time complexity of the program were analyzed. The new developed depletion program was coupled with Monte Carlo program MCMG-II to calculate the benchmark burn-up problem of the first core of China Experimental Fast Reactor (CEFR). The initial verification and validation of the program was performed by the calculation. (author)

  3. Global Warming: Lessons from Ozone Depletion

    Science.gov (United States)

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

  4. Application of backtracking algorithm to depletion calculations

    International Nuclear Information System (INIS)

    Based on the theory of linear chain method for analytical depletion calculations, the burnup matrix is decoupled by the divide and conquer strategy and the linear chain with Markov characteristic is formed. The density, activity and decay heat of every nuclide in the chain then can be calculated by analytical solutions. Every possible reaction path of the nuclide must be considered during the linear chain establishment process. To confirm the calculation precision and efficiency, the algorithm which can cover all the reaction paths and search the paths automatically according to the problem description and precision restrictions should be found. Through analysis and comparison of several kinds of searching algorithms, the backtracking algorithm was selected to establish and calculate the linear chains in searching process using depth first search (DFS) method, forming an algorithm which can solve the depletion problem adaptively and with high fidelity. The complexity of the solution space and time was analyzed by taking into account depletion process and the characteristics of the backtracking algorithm. The newly developed depletion program was coupled with Monte Carlo program MCMG-Ⅱ to calculate the benchmark burnup problem of the first core of China Experimental Fast Reactor (CEFR) and the preliminary verification and validation of the program were performed. (authors)

  5. Deuterium depleted water. Present applications and prospects

    International Nuclear Information System (INIS)

    The deuterium depleted water, DDW, is distilled, microbiologically pure water with an isotopic concentration D/(D+H) under 145 ppm, the natural water value. At ICSI Rm Valcea a procedure was developed and a patent was recorded for the method and installation for obtaining DDW. The procedure consists in vacuum distillation of natural water on columns equipped with highly performing ordered packing. The system allows obtaining DDW at isotopic concentration within the range 20-120 ppm. Biological studies showed that treatment with this DDW reduced significantly the high rate in L929 linear fibroblast cells and annihilated the tumoral growth in xenotransplant. It was suggested that the deuterium occurring naturally has an essential in converting the signals regulating the cellular cycling. A vast program based on collaborations of ICSI with different specialized research institutes in Romania was initiated and important results already obtained among which one can mention: - DDW determines an increase of vascular reactivity seemingly endotelio-dependent and implying radical species (superoxides, nitric oxides); - immunity defense reaction represented by the opsonic, bactericide and phagocytic capacity are stimulated; - animals pre-treated with DDW present an increased resistance to both sub-lethal and lethal doses of gamma radiations, suggesting a radioprotective property; - study of artificial fecundation in fishes with fecundating solution containing an 1:1 mixture of DDW and distilled water showed the beneficent effects both in embryonal development and growth in alevins; - an increase of metabolism rate in aquatic macrophytes following the dilution of spectral energy of sea water mixed with DDW was observed; - studies on three genotypes of Zea mays showed significant effects on coleoptile growth. At present programs for studying prevention and treatment of tumors and various cancer forms are underway

  6. Barium Depletion in Hollow Cathode Emitters

    Science.gov (United States)

    Polk, James E.; Capece, Angela M.; Mikellides, Ioannis G.; Katz, Ira

    2009-01-01

    The effect of tungsten erosion, transport and redeposition on the operation of dispenser hollow cathodes was investigated in detailed examinations of the discharge cathode inserts from an 8200 hour and a 30,352 hour ion engine wear test. Erosion and subsequent re-deposition of tungsten in the electron emission zone at the downstream end of the insert reduces the porosity of the tungsten matrix, preventing the ow of barium from the interior. This inhibits the interfacial reactions of the barium-calcium-aluminate impregnant with the tungsten in the pores. A numerical model of barium transport in the internal xenon discharge plasma shows that the barium required to reduce the work function in the emission zone can be supplied from upstream through the gas phase. Barium that flows out of the pores of the tungsten insert is rapidly ionized in the xenon discharge and pushed back to the emitter surface by the electric field and drag from the xenon ion flow. This barium ion flux is sufficient to maintain a barium surface coverage at the downstream end greater than 0.6, even if local barium production at that point is inhibited by tungsten deposits. The model also shows that the neutral barium pressure exceeds the equilibrium vapor pressure of the impregnant decomposition reaction over much of the insert length, so the reactions are suppressed. Only a small region upstream of the zone blocked by tungsten deposits is active and supplies the required barium. These results indicate that hollow cathode failure models based on barium depletion rates in vacuum dispenser cathodes are very conservative.

  7. Biological effects of deuterium - depleted water

    International Nuclear Information System (INIS)

    Deuterium-depleted water (DDW) is represented by water that has an isotopic content smaller than 145 ppm D/(D + H). DDW production technique consists in the separation of deuterium from water by a continuous distillation process under pressure of about 133.3 mbar. The water used as raw material has a isotopic content of 145 ppm D/(D + H) and can be demineralized water, distillated water or condensed-steam. DDW results as a distillate with an isotopic deuterium content of 15-80 ppm, depending on the level we want to achieve. Beginning with 1996 the Institute of Cryogenics and Isotopic Technologies, DDW producer, co-operated with Romanian specialized institutes for studying the biological effects of DDW. The role of naturally occurring D in living organisms was examined by using DDW instead of natural water. These investigations led to the following conclusions: - DDW caused a tendency towards the increase of the basal tone, accompanied by the intensification of the vasoconstrictor effects of phenylefrine, noradrenaline and angiotensin; the increase of the basal tone and vascular reactivity produced by the DDW persists after the removal of the vascular endothelium; - Animals treated with DDW showed an increase of the resistance both to sublethal and lethal gamma radiation doses, suggesting a radioprotective action by the stimulation of non-specific immune defense mechanisms; - DDW stimulates immuno-defense reactions represented by the opsonic, bactericidal and phagocyte capacity of the immune system together with an increase in the number of poly-morphonuclear neutrophils; - Investigations regarding artificial reproduction of fish with DDW fecundated solutions confirmed favorable influence in embryo growth stage and resistance and following growth stages; - It was studied germination, growth and quantitative character variability in plants; one can remark the favorable influence of DDW on biological processes in plants in various ontogenetic stages. (authors)

  8. Repeated exposure to MDMA provides neuroprotection against subsequent MDMA-induced serotonin depletion in brain

    OpenAIRE

    Bhide, Nirmal S.; Lipton, Jack; Cunningham, Jacobi; Yamamoto, Bryan K.; Gudelsky, Gary A.

    2009-01-01

    Repeated exposure to sub-lethal insults has been reported to result in neuroprotection against a subsequent deleterious insult. The purpose of this study was to evaluate whether repeated exposure (preconditioning) to a non-5-HT depleting dose of MDMA in adult rats provides neuroprotection against subsequent MDMA induced 5-HT depletion. Treatment of rats with MDMA (10 mg/kg, ip every 2 hrs for 4 injections) resulted in a 50-65% depletion of 5-HT in the striatum, hippocampus and cortex, and the...

  9. 公丁香提取物抑制CFTR氯离子通道的发现与研究%The extract of clove inhibits CFTR chloride channel

    Institute of Scientific and Technical Information of China (English)

    栾剑; 张耀方; 杨红

    2015-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) is an epithelial chloride chan‐nel .In recent years ,the blockers of CFTR become the new hot spot in the treatment of secretory di‐arrhea .The aim of this research is using high‐throughput screening techniques screened blockers of CFTR chloride channel from traditional Chinese medicine .In this study ,after 40000 fractions of Chi‐nese herbal medicine have been screened ,clove extract was found .In cell‐based fluorescence assays and voltage clamp experiments ,the best active fraction‐E06 significantly blocks CFTR chloride chan‐nel .Therefore ,clove extract screened from traditional Chinese medicine blocks CFTR chloride chan‐nel and provides a theoretical basis for the in‐depth study of anti‐diarrheal drugs .%囊性纤维化跨膜电导调节因子(CFTR)是一种上皮细胞顶膜中表达的氯离子通道,是近年来治疗分泌型腹泻的新热点。利用高通量筛选技术,自中国传统中药中筛选能够抑制CFTR氯离子通道的中药组分。结果显示,自500种中草药的40000种中药组分中筛选到公丁香。经细胞荧光实验和电压膜片钳实验验证公丁香最佳活性孔———E06对CFTR具有明显的抑制作用,IC50=103 mg/L 。本研究结果为深入探讨公丁香的抗泻药物研发提供理论依据。

  10. Cytotoxicity and glutathione depletion studies using CHOK cells

    International Nuclear Information System (INIS)

    Radiosensitization characteristics of newly synthesized isoindole-4, 7-diones have been established in the authors' laboratories. Cytotoxicity studies of isoindole-4, 7-diones on chinese hamster ovary cell (CHOK) have been carried out. The effects that different concentrations of isoindole-4, 7-diones have on cell growth as a function of time after treatment on both systems (oxic and hypoxic) have been determined. Most of isoindole-4, 7-diones used in these studies show more cytotoxic effect under hypoxic conditions. Gluthathione depletion was also measured in both systems. Most of the quinones studied deplete the concentration of glutathione in the CHOK cells. The results will be compared with similar studies carried out with the well known radiosensitizers misonidazole. It is hoped that the isoindole-r, 7-diones are a new family of chemical radiosensitizers

  11. High pressure elasticity and thermal properties of depleted uranium

    Science.gov (United States)

    Jacobsen, M. K.; Velisavljevic, N.

    2016-04-01

    Studies of the phase diagram of uranium have revealed a wealth of high pressure and temperature phases. Under ambient conditions the crystal structure is well defined up to 100 gigapascals (GPa), but very little information on thermal conduction or elasticity is available over this same range. This work has applied ultrasonic interferometry to determine the elasticity, mechanical, and thermal properties of depleted uranium to 4.5 GPa. Results show general strengthening with applied load, including an overall increase in acoustic thermal conductivity. Further implications are discussed within. This work presents the first high pressure studies of the elasticity and thermal properties of depleted uranium metal and the first real-world application of a previously developed containment system for making such measurements.

  12. Characteristics of depleted uranium for the storage of hydrogen isotopes

    International Nuclear Information System (INIS)

    The characteristics for the hydrogen storage was investigated using depleted uranium that was the waste of nuclear fuel manufacturing. Activation process was conducted to heat the experimental vessel to 450 .deg. C under vacuum and the reaction temperature was room temperature. The absorption reaction between hydrogen and depleted uranium was very fast with rapid increasing of temperature and reached to the saturated state within 10 minutes. The ratio of hydrogen to uranium was 2.95 and the amounts of absorbed hydrogen were 3.5 liter after one hour of reaction. The experimental results of reproducibility showed the similar tendencies after third reaction. The reaction of hydrogen and deuterium showed similar tendencies and the initial reaction rate of deuterium was slower than that of hydrogen. The desorption of absorbed hydrogen started around 250 .deg. C. It was confirmed that the almost absorbed hydrogen was desorbed by heating to 450 .deg. C

  13. Detecting Grain-Boundary Chromium Depletion in Inconel 600

    Science.gov (United States)

    Airey, G. P.; Vaia, A. R.; Pessall, N.; Aspden, R. G.

    1981-11-01

    Techniques to evaluate grain-boundary chromium depletion in Inconel Alloy 600 were investigated. Procedures studied were a modified Huey test, reactivation polarization, magnetic permeability measurements, and eddy current measurements. Results from these tests were correlated with susceptibility to stress-assisted intergranular cracking in polythionic acid. Thermally treated Inconel Alloy 600 steam generator tubing was the principal source of material evaluated, but experimental heats of Ni-Cr-Fe alloys with 8-18 wt.% Cr were prepared to determine the critical chromium level below which stress-assisted intergranular cracking occurs; this critical chromium content was found to be between 9.8 and 11.7 wt.%. All four techniques were considered suitable to evaluate grain-boundary chromium depletion; the modified Huey test and reactivation polarization technique showed a greater sensitivity than the magnetic permeability and eddy current measurements.

  14. Lower hybrid wave phenomena associated with density depletions

    Science.gov (United States)

    Seyler, C. E.

    1994-01-01

    A fluid description of lower hybrid, whistler and magnetosonic waves is applied to study wave phenomena near the lower hybrid resonance associated with plasma density depletions. The goal is to understand the nature of lower hybrid cavitons and spikelets often associated with transverse ion acceleration events in the auroral ionosphere. Three-dimensional simulations show the ponderomotive force leads to the formation of a density cavity (caviton) in which lower hybrid wave energy is concentrated (spikelet) resulting in a three-dimensional collapse of the configuration. Plasma density depletions of the order of a few percent are shown to greatly modify the homogeneous linear properties of lower hybrid waves and account for many of the observed features of lower hybrid spikelets.

  15. PP005. Vitamin D depletion aggravates hypertension in transgenic rats

    DEFF Research Database (Denmark)

    Bjørkholt Andersen, Louise; Herse, Florian; Christesen, Henrik Thybo;

    2013-01-01

    overexpressing the human renin and angiotensinogen genes, group 1 (n=18) received vitamin D depleted chow; group 2 (n=15) standard chow and intraperitoneal paricalcitol at 800ng/kg thrice weekly; and group 3 (n=15) standard chow and vehicle injections. Blood pressure (tail cuff) and 24-h albuminuria were......INTRODUCTION: Vitamin D may ameliorate hypertension and kidney disease through genomic and extra-genomic pathways. OBJECTIVE: To investigate the impact of vitamin D in a transgenic rat model of angiotensin II-mediated hypertensive organ failure. METHODS: In 4-week-old age-matched rats...... determined once weekly. After three weeks, animals were sacrificed. Heart tissue was examined for atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) by RT-PCR. RESULTS: The vitamin D depleted group had higher blood pressure at week 1 (mean difference 23.4mmHg, 95% CI 9.1-37.7) and tended to...

  16. 先天性双侧输精管缺如患者囊性纤维化跨膜传导调节因子基因的检测%CFTR gene mutation in patients with congenital bilateral absence of vas deferens

    Institute of Scientific and Technical Information of China (English)

    卢少明; 王来诚; 张浩波; 李晓; 刘蛟龙; 崔延义; 陈子江

    2013-01-01

    Objective To study the frequency of cystic fibrosis transmembrane conductance regulator(CFTR)mutations in patients with congenital bilateral absence of vas deferens(CBAVD).Methods Eighty-five CBAVD patients were collected from May 2007 to May 2009.The diagnosis of CBAVD included azoospermia,normal of 4 sex hormone items,absence of seminal vesicle,normal volume of testicular and epididymis dilated siltation.And 85 normal fertile men served as controls.Genomic DNA was isolated from peripheral blood.The mutations of CFTR exons 10,11 were detected by PCR-single strand conformation polymorphism,and direct sequencing was performed on 85 cases of CBAVD and the control males.Results Of the 85 CBAVD,10 cases(11.8%)exhibited an abnormal CFTR gene mutation,with 4 cases I556V,2 cases M469V,and 1 case of E527N,A F508,L558S,S485C.No mutations were detected in 85 controls.There was a significant difference between the 2 groups(x2 =8.606,P =0.003).Conclusions CBAVD might be caused by the CFTR mutations.The frequencies and the spectrum of CFTR mutations might be different from those Caucasian population in the west country.%目的 探讨先天性双侧输精管缺如(CBAVD)患者与囊性纤维化跨膜传导调节因子(CFTR)基因突变的关系. 方法 收集2007年5月至2009年5月85例CBAVD患者.CBAVD诊断依据:无精子;性激素4项正常;双侧输精管未触及;双睾丸体积正常,附睾饱满淤积.另设健康已生育男性85例作为对照.抽取外周血,应用聚合酶链反应-单链构象多态及PCR产物直接序列测定法检测患者及对照组CFTR基因第10,11外显子,比较两组的突变情况. 结果 CBAVD组85例,CFTR基因突变10例,占11.8%,分别是I556V突变4例,M469V突变2例,E527N、△F508、L558S、S485C各1例.对照组85例均未见突变.两组间比较差异有统计学意义(x2=8.606,P=0.003).结论 CBAVD主要由CFTR基因突变引起,CFTR基因突变的位点与频率与西方白种人有所不同.

  17. 先天性双侧输精管缺如患者CFTR基因启动子区域基因突变检测%Detection of promoter region of CFTR gene in Chinese congenital bilateral absence of vas deferens

    Institute of Scientific and Technical Information of China (English)

    吴晓; 张炎; 杨晓健; 陈石涛; 袁萍; 张滨

    2015-01-01

    目的 探讨先天性双侧输精管缺如患者囊性纤维化跨膜转导因子(CFTR)基因启动子区域的基因突变情况.方法 采用PCR技术结合DNA直接测序的方法检测2013年5月至2015年1月于中山大学附属第三医院诊断明确的11例先天性双侧输精管缺如汉族患者及50名健康已生育汉族男性的CFTR基因5'端ATG上游3.8 kb的启动子区域的突变情况,并在NCBI和Cystic Fibrosis Mutation Database在线比对,利用Transfac在线预测及系统发生足迹法联合已经报道的转录因子作用元件,探讨所检测之碱基变异与启动子调控作用的关系.结果 11例汉族先天性双侧输精管缺如患者中发现c.-8G>C(1例)、c.-966T> G(7例)2个已知CFTR启动子区域的多态性位点及c.-195C>A(1例)1个单核苷酸位点变异,其中,c.-195C>A位于物种间启动子保守区域.结论 除外多态性位点,在中国汉族先天性双侧输精管缺如患者CFTR基因启动子区域检测到一个单核苷酸变异,其与疾病发生的关系仍需进一步行生物学实验验证.%Objective To detect the variants in the promoter region of the CFTR gene in congenital bilateral absence of vas deferens (CBAVD).Methods A total of 11 CBAVD patients and 50 healthy men as control were enrolled in the study from May 2013 to January 2015.Sanger sequencing was performed in the promoter region of 3.8 kb of the CFTR gene on the PCR products.The genome sequence of the CFTR gene was compared and analyzed with the website of NCBI and Cystic Fibrosis Mutation Database.Also,Transfac and phylogenetic footprinting method was used to investigate the relationship between the promoter region variants and the transcription factors function components.Results SNP of c.-8G > C (n =1) and c.-966T > G(n =7),as well as one single nucleotide variant of c.-195C > A (n =1) were identified in the promoter region of the CBAVD patients,of which c.-195C > A was in the conserved domains of the promoter

  18. Depleted uranium report from the Health Council of the Netherlands

    International Nuclear Information System (INIS)

    The Health Council of the Netherlands, which is an independent scientific advisory body established in 1902 to advise the government and Parliament on the current level of knowledge with respect to public health issues', has recently published an overview report on depleted uranium. The title of the report is Health risks of exposure to depleted uranium' and it is freely available in both English and the original Dutch language. A brief summary of the report that was published on 16 May 2001 is presented here. The use of ammunition containing depleted uranium (DU) in Kosovo and elsewhere in the Balkans has provoked disquiet in Europe. In the Netherlands, concern over the release of this material had already been aroused previously following the crash of the El-Al airliner in the Bijlmermeer district of Amsterdam in 1992. It was against this background that the President of the Health Council decided to set up a Committee charged with the task of reviewing the health risks of exposure to DU and the preventive measures required for individuals present in areas where DU has been released into the environment. After reviewing the properties of uranium in general and depleted uranium in particular, and presenting data on the occurrence of the element in the environment and biological tissues, the committee assessed the chemical and radiological health effect of uranium and uranium compounds. The Health Council Committee concludes that radioactive contamination of the lungs is the principal health risk to be considered in connection with exposure to slightly soluble uranium compounds in the atmosphere. For soluble compounds, the chemical toxic effect in the kidneys is the primary consideration. The toxicological effects are to some extent concordant with those of other heavy metals. For relevant exposure scenarios the Committee does not anticipate that exposure to DU will result in a demonstrable increased risk of diseases and symptoms among exposed individuals as a

  19. Verification of the COCAGNE core code using cluster depletion calculations

    International Nuclear Information System (INIS)

    EDF/R and D is developing a new calculation scheme based on the transport- Simplified Pn (SPn) approach. The lattice code used is the deterministic code APOLLO2, developed at CEA with the support of EDF and AREVA-NP. The core code is the code COCAGNE, developed at EDF R and D. The latter can take advantage of a microscopic depletion solver which improves the treatment of spectral history effects. This solver can resort to a specific correction based on the use of the Pu239 concentration as a spectral indicator. In order to evaluate the improvements brought by this Pu239 correction model, one uses (3x3 assemblies) cluster depletion calculations as test-cases. UOX and UOX/MOX clusters are both considered. As a reference, APOLLO2 depletion calculations of these clusters, using a critical boron (CB) search scheme at each calculation step, are performed. This choice of methodology (using CB search instead of a fixed average CB) enables to highlight historical spectral effects related to the boron concentration. This methodology is also more consistent with the depletion calculation of real cores. Pin by pin COCAGNE calculations are performed and compared with the APOLLO2 results. The analysis of the results obtained shows that the boron concentration computed by COCAGNE gets more consistent with APOLLO2 when the Pu239 corrector is used, especially for UOX/MOX clusters. As for pin power distribution, the use of the Pu239 model also enables to reduce slightly the gap between APOLLO2 and COCAGNE. This work will be extended to clusters with gadolinium-poisoned fuel assemblies and reflector regions. (author)

  20. UniProt search blastx result: AK287488 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287488 J043029O04 Q9TSP5|CFTR_PAPAN Cystic fibrosis transmembrane conductance regulator (CFTR) ... transporter sub-family C member 7) - Papio anubis (Olive ... baboon) 2.00E-64 ...

  1. Expressions and signification of CFTR and SPINK1 in chronic pancreatitis and chronic pancreatitis%CFTR及SPINK1蛋白在慢性胰腺炎及胰腺癌中的表达及其意义

    Institute of Scientific and Technical Information of China (English)

    张敏; 王银萍; 倪劲松; 薛世泉; 邹亚彬; 张丽红

    2011-01-01

    .Results  CFTR and SPINK 1 protein in normal pancreatic tissue showed strong expression ,the positive expression rate is 100% (10/10) ;Decreased expression in chronic pancreatitis ,the positive expression rate is 50% (10/20) and 55% (11/20) respectively ,compared with the normal pancreas ,statistically significant( P < 0 .05) ;.The expression of CFTR and SPINK 1 was significantly reduced in pancreatic cancer ,the positive expression rate is 10% (3/30)and 6 .7% (2/30)respectively ,compared with the the normal pancreas and chronic pancreatitis group ,there were significant differences( P < 0 .05) .Conclusion  Abnormal expression of CFTR and SPINK 1 may play an important role in patients with chronic pancreatitis to pancreatic cancer and its transformation process .

  2. Environmental impacts of options for disposal of depleted uranium tetrafluoride (UF4)

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) evaluated options for managing its depleted uranium hexafluoride (UF6) inventory in the Programmatic Environmental Impact Statement for the Long-Term Management and Use of Depleted Uranium Hexafluoride (PEIS) of April 1999. Along with the impacts from other management options, the PEIS discussed the environmental impacts from the disposal of depleted uranium oxide, which could result from the chemical conversion of depleted UF6. It has been suggested that the depleted UF6 could also be converted to uranium tetrafluoride (UF4) and disposed of. This report considers the potential environmental impacts from the disposal of DOE's depleted UF6 inventory after its conversion to UF4. The impacts were evaluated for the same three disposal facility options that were considered in the PEIS for uranium oxide: shallow earthen structures, belowground vaults, and mines. They were evaluated for a dry environmental setting representative of the western United States. To facilitate comparisons and future decision making, the depleted UF4 disposal analyses performed and the results presented in this report are at the same level of detail as that in the PEIS

  3. EZH2 depletion blocks the proliferation of colon cancer cells.

    Directory of Open Access Journals (Sweden)

    Bettina Fussbroich

    Full Text Available The Enhancer of Zeste 2 (EZH2 protein has been reported to stimulate cell growth in some cancers and is therefore considered to represent an interesting new target for therapeutic intervention. Here, we investigated a possible role of EZH2 for the growth control of colon cancer cells. RNA interference (RNAi-mediated intracellular EZH2 depletion led to cell cycle arrest of colon carcinoma cells at the G1/S transition. This was associated with a reduction of cell numbers upon transient transfection of synthetic EZH2-targeting siRNAs and with inhibition of their colony formation capacity upon stable expression of vector-borne siRNAs. We furthermore tested whether EZH2 may repress the growth-inhibitory p27 gene, as reported for pancreatic cancer. However, expression analyses of colon cancer cell lines and colon cancer biopsies did not reveal a consistent correlation between EZH2 and p27 levels. Moreover, EZH2 depletion did not re-induce p27 expression in colon cancer cells, indicating that p27 repression by EZH2 may be cell- or tissue-specific. Whole genome transcriptome analyses identified cellular genes affected by EZH2 depletion in colon cancer cell lines. They included several cancer-associated genes linked to cellular proliferation or invasion, such as Dag1, MageD1, SDC1, Timp2, and Tob1. In conclusion, our results demonstrate that EZH2 depletion blocks the growth of colon cancer cells. These findings might provide benefits for the treatment of colon cancer.

  4. Inhomogeneous depletion of oxygen ions in metal oxide nanoparticles

    Science.gov (United States)

    Vykhodets, Vladimir B.; Jarvis, Emily A. A.; Kurennykh, Tatiana E.; Beketov, Igor V.; Obukhov, Sviatoslav I.; Samatov, Oleg M.; Medvedev, Anatoly I.; Davletshin, Andrey E.; Whyte, Travis H.

    2016-02-01

    Zirconia and yttria stabilized zirconia (YSZ) have multiple uses, including catalysis, fuel cells, dental applications, and thermal coatings. We employ nuclear reaction analysis to determine elemental composition of YSZ nanoparticles synthesized by laser evaporation including 18O studies to distinguish between oxide and adsorbed oxygen content as a function of surface area. We see dramatic deviation from stoichiometry that can be traced to loss of oxygen from the oxide near the surface of these nanopowders. Density functional calculations are coupled with these experimental studies to explore the electronic structure of nonstoichiometric surfaces achieved through depletion of oxygen. Our results show oxygen-depleted surfaces present under oxygen potentials where stoichiometric, oxygen-terminated surfaces would be favored thermodynamically for crystalline systems. Oxygen depletion at nanopowder surfaces can create effective two-dimensional surface metallic states while maintaining stoichiometry in the underlying nanoparticle core. This insight into nanopowder surfaces applies to dissimilar oxides of aluminum and zirconium indicating synthesis conditions may be more influential than the inherent oxide properties and displaying need for distinct models for nanopowders of these important engineering materials where surface chemistry dominates performance.

  5. Radioprotective and Immunostimulating Effects of Deuterium-Depleted Water

    International Nuclear Information System (INIS)

    Full text: Mice fed during 15 days with Deuterium-Depleted Water (30 ppm deuterium) had a statistically significant increased survival compared with control groups fed with normal distilled water (150 ppm deuterium) after 8.5 Gy irradiation (61% survival in test group towards 25% in control group). Hematological picture showed maintaining of the normal WBC, RBC and platelet count in test groups. Immunological parameters (serum opsonic and bactericidal capacity, bactericidal capacity of the peritoneal macrophages) showed a marked increase in test groups compared to a severe decrease in the control groups. Auxiliary tests using chemical radiomimetics (hydrochloric embihine) and immunosupressors (cyclophosphamide) showed a strong protective effect of deuterium-depleted water against the decrease of the leukocyte counts and other immunologic parameters. In conditions of experimental inflammation with subcutaneous-implanted pellets, deuterium-depleted water feeding statistically significant increased inflammatory response, obviated by increased percentages of PMN and lymphocytes in the peripheral blood and increased phagocytic capacity of the peripheral blood PMN. Experimental infections with K. pneumoniae 506 and S. pneumoniae 558 in mice irradiated or treated with cyclophosphamide showed increased non-specific immunity parameters. All results show a marked intensification of the immune defenses and increased proliferation of the peripheral blood cells, probably accounting for the radioprotective effects. (author)

  6. DUPoly process for treatment of depleted uranium and production of beneficial end products

    International Nuclear Information System (INIS)

    The present invention provides a process of encapsulating depleted uranium by forming a homogeneous mixture of depleted uranium and molten virgin or recycled thermoplastic polymer into desired shapes. Separate streams of depleted uranium and virgin or recycled thermoplastic polymer are simultaneously subjected to heating and mixing conditions. The heating and mixing conditions are provided by a thermokinetic mixer, continuous mixer or an extruder and preferably by a thermokinetic mixer or continuous mixer followed by an extruder. The resulting DUPoly shapes can be molded into radiation shielding material or can be used as counter weights for use in airplanes, helicopters, ships, missiles, armor or projectiles

  7. Deuterium depleted water. Current and potential applications

    International Nuclear Information System (INIS)

    Deuterium depleted water (DDW) is distilled, microbiologically pure water with a D/(D+H) isotopic content lower than the value 145 ppm of natural water. It is practically unnoxious, with a toxic potential pT 50 > 0.01 mol/kg c.m. At ICSI a procedure was worked out and patented and a facility was achieved for obtaining DDW. The procedure consists in continuous vacuum distillation of natural water on columns with highly performing ordered packings. DDW of controlled isotopic concentration D/(D+H) within the range 20-120 ppm, of quality similar to distilled water can be currently produced. Many studies were reported in literature evidencing the active biological properties of DDW. DDW lowered significantly the high division rate of the L929 linear fibroblast cell and blocked the tumoral growth in xenotransplants. It was suggested that the naturally occurring deuterium plays a prominent role in converting the signal implied in cellular cycle mechanism. Having in view the high significance of the experiments in this field, ICSI has promoted a programme of collaborations with Romanian institutes of various specialties to evaluate the biological effects of DDW with a D/(D+H) concentration of about 30 ppm. The following results obtained so far obtained should be highlighted: - DDW causes an increase of vascular reactivity both in rings isolated from thorax aorta and in vivo upon arterial pressure. The reactivity increase seems to be endothelium-depended and is achieved with participation of the radical species (superoxides, nitric oxide); - DDW stimulates the immunodefence reaction, as represented by the opsonic, bactericide and phagocytic capacity of the immunity system as well as by the increase of the number of polymorphonucleates; - animals pre-treated with DDW exhibit an increased resistance both to sublethal and lethal γ radiation doses, what suggests a radioprotective effect; - studies on artificial fecundation in fishes with fecundant solutions containing a 1

  8. Elemental depletions in the Magellanic Clouds and the evolution of depletions with metallicity

    CERN Document Server

    Tchernyshyov, Kirill; Seale, Jonathan; Fox, Andrew; Friedman, Scott D; Dwek, Eli; Galliano, Frédéric; Sembach, Kenneth

    2015-01-01

    We present a study of the composition of gas and dust in the Large and Small Magellanic Clouds (LMC and SMC, together -- the MCs) as measured by UV absorption spectroscopy. We have measured P II and Fe II along 85 sightlines toward the MCs using archival FUSE observations. For 16 of those sightlines, we have measured Si II, Cr II, and Zn II from new HST COS observations. We have combined these measurements with H I and H$_2$ column densities and reference stellar abundances from the literature to derive gas-phase abundances, depletions, and gas-to-dust ratios (GDRs). 80 of our 84 P measurements and 13 of our 16 Zn measurements are depleted by more than 0.1 decades, suggesting that P and Zn abundances are not accurate metallicity indicators at and above the metallicity of the SMC. The maximum P and Zn depletions are the same in the MW, LMC, and SMC. Si, Cr, and Fe are systematically less depleted in the SMC than in the MW or LMC. The minimum Si depletion in the SMC is consistent with zero. Our depletion-derive...

  9. Copenhagen delegates advance phaseout of ozone depleters

    International Nuclear Information System (INIS)

    As expected, delegates at the United Nations Ozone Layer Conference in Copenhagen sped up ozone depleter phaseouts from the 1987 Montreal Protocol and the 1990 London amendments. The changes bring the worldwide production phaseout of chlorofluorocarbons (CFCs) and other ozone depleters in developed countries in line with U.S. and European plans announced earlier this year. Adjustments to the protocol, which are binding on the signatories, change the phaseout for CFC, carbon tetrachloride, and methyl chloroform production and consumption to January 1, 1996 from 2000. The 75% reduction of 1986 levels from CFCs by January 1, 1994 is a compromise between European pressure for an 85% cut and the US goal of 70%. Halon production is to end January 1, 1994, as anticipated. Developing countries continue to have a 10-year grace period. Friends of the Earth ozone campaign director Liz Cook counters that the phaseout dates were scheduled with concern for the chemical industry, not for the ozone layer

  10. Depleted uranium hexafluoride: Waste or resource?

    Energy Technology Data Exchange (ETDEWEB)

    Schwertz, N.; Zoller, J.; Rosen, R.; Patton, S. [Lawrence Livermore National Lab., CA (United States); Bradley, C. [USDOE Office of Nuclear Energy, Science, Technology, Washington, DC (United States); Murray, A. [SAIC (United States)

    1995-07-01

    the US Department of Energy is evaluating technologies for the storage, disposal, or re-use of depleted uranium hexafluoride (UF{sub 6}). This paper discusses the following options, and provides a technology assessment for each one: (1) conversion to UO{sub 2} for use as mixed oxide duel, (2) conversion to UO{sub 2} to make DUCRETE for a multi-purpose storage container, (3) conversion to depleted uranium metal for use as shielding, (4) conversion to uranium carbide for use as high-temperature gas-cooled reactor (HTGR) fuel. In addition, conversion to U{sub 3}O{sub 8} as an option for long-term storage is discussed.

  11. The depletion of the stratospheric ozone layer

    International Nuclear Information System (INIS)

    The protection of the Earth's ozone layer is of the highest importance to mankind. The dangers of its destruction are by now well known. The depletion of that layer has reached record levels. The Antarctic ozone hole covered this year a record area. The ozone layer is predicted to begin recovery in the next one or two decades and should be restored to pre-1980 levels by 2050. This is the achievement of the regime established by the 1985 Vienna Convention for the Protection of the Ozone Layer and the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer. The regime established by these two agreements has been revised, and made more effective in London (1990), Copenhagen (1992), Vienna (1995), and Beijing (1999)

  12. The ultimate disposition of depleted uranium

    Energy Technology Data Exchange (ETDEWEB)

    Lemons, T.R. [Uranium Enrichment Organization, Oak Ridge, TN (United States)

    1991-12-31

    Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

  13. Educational software on the ozone layer Depletion

    OpenAIRE

    Psomiadis, Ploutarchos; Chalkidis, Anthimos; Saridaki, Anna; Tampakis, Constantine (Konstantinos); Skordoulis, Constantine

    2007-01-01

    This paper describes the design and the formative evaluation of educational software concerning the ‘Depletion of the Ozone Layer’ designed for the students of the Faculty of Primary Education (pre-service teachers) of the National and Kapodistrian University of Athens. The selection of the topic was based on: i) environmental criteria (importance of the phenomenon, complexity of the phenomenon), ii) societal criteria (local interest, human activities effects), iii) pedagogical cr...

  14. Effects of Streambed Conductance on Stream Depletion

    OpenAIRE

    Greg Lackey; Roseanna M. Neupauer; John Pitlick

    2015-01-01

    Stream depletion, which is the reduction in flow rate of a stream or river due to the extraction of groundwater in a hydraulically connected stream-aquifer system, is often estimated using numerical models. The accuracy of these models depends on the appropriate parameterization of aquifer and streambed hydraulic properties. Streambed conductance is a parameter that relates the head difference between the stream and aquifer to flow across the stream channel. It is a function of streambed hydr...

  15. Ecological and corrosion behavior of depleted uranium

    OpenAIRE

    Stojanović Mirjana D.; Lačnjevac Časlav M.; Mihajlović Marija L.; Petrović Marija V.; Šoštarić Tanja D.; Petrović Jelena T.; Lopičić Zorica R.

    2015-01-01

    Environmental pollution with radionuclides, particularly uranium and its decay products is a serious global problem. The current scientific studies estimated that the contamination originating from TENORM, caused by nuclear and non-nuclear technologies, has significantly increased natural level of radioactivity in the last thirty years. During the last decades all the more were talking about the "new pollutant" - depleted uranium (DU), which has been used i...

  16. Depleted uranium during the Kosovo war

    International Nuclear Information System (INIS)

    Using the depleted uranium (DU) in the war and civil aims is considered. There are characterized the head parts of projectiles (drifts) from DU, used during Balkan wars, are described. The uranium isotope activity and exposure dose rates from β, γ and photon radiation of the drifts are investigated. The content of uranium and plutonium isotopes in the soil samples are measured. It is concluded that DU cannot exercise the acute influence on the health of military man and civil population

  17. Depletion modeling of liquid dominated geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, G.

    1984-06-01

    Depletion models for liquid-dominated geothermal reservoirs are derived and presented. The depletion models are divided into two categories: confined and unconfined. For both cases depletion models with no recharge (or influx), and depletion models including recharge, are used to match field data from the Svartsengi high temperature geothermal field in Iceland. The influx models included with the mass and energy balances are adopted from the petroleum engineering literature. The match to production data from Svartsengi is improved when influx was included. The Schilthuis steady-state influx gives a satisfactory match. The finite aquifer method of Fetkovitch, and the unsteady state method of Hurst gave reasonable answers, but not as good. The best match is obtained using Hurst simplified solution when lambda = 1.3 x 10{sup -4} m{sup -1}. From the match the cross-sectional area of the aquifer was calculated as 3.6 km{sup 2}. The drawdown was predicted using the Hurst simplified method, and compared with predicted drawdown from a boiling model and an empirical log-log model. A large difference between the models was obtained. The predicted drawdown using the Hurst simplified method falls between the other two. Injection has been considered by defining the net rate as being the production rate minus the injection rate. No thermal of transient effects were taken into account. Prediction using three different net rates shows that the pressure can be maintained using the Hurst simplified method if there is significant fluid reinjection. 32 refs., 44 figs., 2 tabs.

  18. Ecological and corrosion behavior of depleted uranium

    Directory of Open Access Journals (Sweden)

    Stojanović Mirjana D.

    2015-01-01

    Full Text Available Environmental pollution with radionuclides, particularly uranium and its decay products is a serious global problem. The current scientific studies estimated that the contamination originating from TENORM, caused by nuclear and non-nuclear technologies, has significantly increased natural level of radioactivity in the last thirty years. During the last decades all the more were talking about the "new pollutant" - depleted uranium (DU, which has been used in anti-tank penetrators because of its high density, penetration and pyrophoric properties. It is estimated that during the Gulf War, the war in Bosnia and Yugoslavia and during the invasion of Iraq, 1.4 million missiles with depleted uranium was fired. During the NATO aggression against the ex Yugoslavia in 1999., 112 locations in Kosovo and Metohija, 12 locations in southern Serbia and two locations in Montenegro were bombed. On this occasion, approximately 10 tons of depleted uranium were entered into the environment, mainly on land, where the degree of contamination ranged from 200 Bq / kg to 235 000 Bq/kg, which is up to 1000 times higher than the natural level. Fourteen years ago there was very little information about the behavior of ecological systems damaged by DU penetrators fired. Today, unfortunately, we are increasingly faced with the ―invisible threat" of depleted uranium, which has a strong radioactive and hemotoxic impact on human health. Present paper provides a detailed overview of the current understanding of corrosion and corrosion behavior of DU and environmental factors that control corrosion, together with indicators of environmental impact in order to highlight areas that need further attention in developing remediation programs.

  19. Optical assessment of phytoplankton nutrient depletion

    DEFF Research Database (Denmark)

    Heath, M.R.; Richardson, Katherine; Kiørboe, Thomas

    1990-01-01

    The ratio of light absorption at 480 and 665 nm by 90% acetone extracts of marine phytoplankton pigments has been examined as a potential indicator of phytoplankton nutritional status in both laboratory and field studies. The laboratory studies demonstrated a clear relationship between nutritional......-replete and nutrient-depleted cells. The field data suggest that the absorption ratio may be a useful indicator of nutritional status of natural phytoplankton populations, and can be used to augment the interpretation of other data....

  20. Barium depletion in hollow cathode emitters

    International Nuclear Information System (INIS)

    Dispenser hollow cathodes rely on a consumable supply of Ba released by BaO-CaO-Al2O3 source material in the pores of a tungsten matrix to maintain a low work function surface. The examination of cathode emitters from long duration tests shows deposits of tungsten at the downstream end that appear to block the flow of Ba from the interior. In addition, a numerical model of Ba transport in the cathode plasma indicates that the Ba partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant Ba-producing reaction, and it was postulated previously that this would suppress Ba loss in the upstream part of the emitter. New measurements of the Ba depletion depth from a cathode insert operated for 8200 h reveal that Ba loss is confined to a narrow region near the downstream end, confirming this hypothesis. The Ba transport model was modified to predict the depletion depth with time. A comparison of the calculated and measured depletion depths gives excellent qualitative agreement, and quantitative agreement was obtained assuming an insert temperature 70 °C lower than measured beginning-of-life values

  1. Barium depletion in hollow cathode emitters

    Energy Technology Data Exchange (ETDEWEB)

    Polk, James E., E-mail: james.e.polk@jpl.nasa.gov; Mikellides, Ioannis G.; Katz, Ira [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States); Capece, Angela M. [Graduate Aerospace Laboratories, California Institute of Technology, Pasadena, California 91125 (United States)

    2016-01-14

    Dispenser hollow cathodes rely on a consumable supply of Ba released by BaO-CaO-Al{sub 2}O{sub 3} source material in the pores of a tungsten matrix to maintain a low work function surface. The examination of cathode emitters from long duration tests shows deposits of tungsten at the downstream end that appear to block the flow of Ba from the interior. In addition, a numerical model of Ba transport in the cathode plasma indicates that the Ba partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant Ba-producing reaction, and it was postulated previously that this would suppress Ba loss in the upstream part of the emitter. New measurements of the Ba depletion depth from a cathode insert operated for 8200 h reveal that Ba loss is confined to a narrow region near the downstream end, confirming this hypothesis. The Ba transport model was modified to predict the depletion depth with time. A comparison of the calculated and measured depletion depths gives excellent qualitative agreement, and quantitative agreement was obtained assuming an insert temperature 70 °C lower than measured beginning-of-life values.

  2. Barium depletion in hollow cathode emitters

    Science.gov (United States)

    Polk, James E.; Mikellides, Ioannis G.; Capece, Angela M.; Katz, Ira

    2016-01-01

    Dispenser hollow cathodes rely on a consumable supply of Ba released by BaO-CaO-Al2O3 source material in the pores of a tungsten matrix to maintain a low work function surface. The examination of cathode emitters from long duration tests shows deposits of tungsten at the downstream end that appear to block the flow of Ba from the interior. In addition, a numerical model of Ba transport in the cathode plasma indicates that the Ba partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant Ba-producing reaction, and it was postulated previously that this would suppress Ba loss in the upstream part of the emitter. New measurements of the Ba depletion depth from a cathode insert operated for 8200 h reveal that Ba loss is confined to a narrow region near the downstream end, confirming this hypothesis. The Ba transport model was modified to predict the depletion depth with time. A comparison of the calculated and measured depletion depths gives excellent qualitative agreement, and quantitative agreement was obtained assuming an insert temperature 70 °C lower than measured beginning-of-life values.

  3. Upscaling of gas relative permeability during pressure depletion

    OpenAIRE

    Grepstad, Kristian

    2011-01-01

    Pressure depletion of an oil reservoir will result in release of dissolved gas when the bubble point of the oil is reached in the reservoir. This liberated gas will segregate upwards in the reservoir with low mobility until a vertical flow barrier is met by the gas. Liberated gas will accumulate below this barrier and create thin "layers" with high gas saturation, where the mobility of gas becomes high. These thin layers with high mobility will result in a relatively quick production of the l...

  4. Terrestrial Ozone Depletion Due to a Milky Way Gamma-Ray Burst

    CERN Document Server

    Thomas, B C; Melott, A L; Laird, C M; Stolarski, R S; Gehrels, N; Cannizzo, J K; Hogan, D P; Thomas, Brian C.; Jackman, Charles H.; Melott, Adrian L.; Laird, Claude M.; Stolarski, Richard S.; Gehrels, Neil; Cannizzo, John K.; Hogan, Daniel P.

    2004-01-01

    Based on cosmological rates, it is probable that at least once in the last Gy the Earth has been irradiated by a gamma-ray burst in our Galaxy from within 2 kpc. Using a two-dimensional atmospheric model we have computed the effects upon the Earth's atmosphere of one such burst. A ten second burst delivering 100 kJ m^-2 to the Earth results in globally averaged ozone depletion of 35%, with depletion reaching 55% at some latitudes. Significant global depletion persists for over 5 years after the burst. This depletion would have dramatic implications for life since a 50% decrease in ozone column density results in approximately three times the normal UVB flux. Widespread extinctions are likely, based on extrapolation from UVB sensitivity of modern organisms

  5. Terrestrial Ozone Depletion Due to a Milky Way Gamma-Ray Burst

    Science.gov (United States)

    Thomas, Brian C.; Jackman, Charles H.; Melott, Adrian L.; Laird, Claude M.; Stolarski, Richard S.; Gehrels, Neil; Cannizzo, John K.; Hogan, Daniel P.

    2005-01-01

    Based on cosmological rates, it is probable that at least once in the last Gy the Earth has been irradiated by a gamma-ray burst in our Galaxy from within 2 kpc. Using a two-dimensional atmospheric model we have computed the effects upon the Earth's atmosphere of one such burst. A ten second burst delivering 100 kJ/sq m to the Earth results in globally averaged ozone depletion of 35%, with depletion reaching 55% at some latitudes. Significant global depletion persists for over 5 years after the burst. This depletion would have dramatic implications for life since a 50% decrease in ozone column density results in approximately three times the normal UVB flux. Widespread extinctions are likely, based on extrapolation from UVB sensitivity of modern organisms.

  6. The CFTR Met 470 allele is associated with lower birth rates in fertile men from a population isolate.

    Directory of Open Access Journals (Sweden)

    Gülüm Kosova

    2010-06-01

    Full Text Available Although little is known about the role of the cystic fibrosis transmembrane regulator (CFTR gene in reproductive physiology, numerous variants in this gene have been implicated in etiology of male infertility due to congenital bilateral absence of the vas deferens (CBAVD. Here, we studied the fertility effects of three CBAVD-associated CFTR polymorphisms, the (TGm and polyT repeat polymorphisms in intron 8 and Met470Val in exon 10, in healthy men of European descent. Homozygosity for the Met470 allele was associated with lower birth rates, defined as the number of births per year of marriage (P = 0.0029. The Met470Val locus explained 4.36% of the phenotypic variance in birth rate, and men homozygous for the Met470 allele had 0.56 fewer children on average compared to Val470 carrier men. The derived Val470 allele occurs at high frequencies in non-African populations (allele frequency = 0.51 in HapMap CEU, whereas it is very rare in African population (Fst = 0.43 between HapMap CEU and YRI. In addition, haplotypes bearing Val470 show a lack of genetic diversity and are thus longer than haplotypes bearing Met470 (measured by an integrated haplotype score [iHS] of -1.93 in HapMap CEU. The fraction of SNPs in the HapMap Phase2 data set with more extreme Fst and iHS measures is 0.003, consistent with a selective sweep outside of Africa. The fertility advantage conferred by Val470 relative to Met470 may provide a selective mechanism for these population genetic observations.

  7. Impact of the CFTR-potentiator ivacaftor on airway microbiota in cystic fibrosis patients carrying a G551D mutation.

    Directory of Open Access Journals (Sweden)

    Cédric Bernarde

    Full Text Available Airway microbiota composition has been clearly correlated with many pulmonary diseases, and notably with cystic fibrosis (CF, an autosomal genetic disorder caused by mutation in the CF transmembrane conductance regulator (CFTR. Recently, a new molecule, ivacaftor, has been shown to re-establish the functionality of the G551D-mutated CFTR, allowing significant improvement in lung function.The purpose of this study was to follow the evolution of the airway microbiota in CF patients treated with ivacaftor, using quantitative PCR and pyrosequencing of 16S rRNA amplicons, in order to identify quantitative and qualitative changes in bacterial communities. Three G551D children were followed up longitudinally over a mean period of more than one year covering several months before and after initiation of ivacaftor treatment.129 operational taxonomy units (OTUs, representing 64 genera, were identified. There was no significant difference in total bacterial load before and after treatment. Comparison of global community composition found no significant changes in microbiota. Two OTUs, however, showed contrasting dynamics: after initiation of ivacaftor, the relative abundance of the anaerobe Porphyromonas 1 increased (p<0.01 and that of Streptococcus 1 (S. mitis group decreased (p<0.05, possibly in relation to the anti-Gram-positive properties of ivacaftor. The anaerobe Prevotella 2 correlated positively with the pulmonary function test FEV-1 (r=0.73, p<0.05. The study confirmed the presumed positive role of anaerobes in lung function.Several airway microbiota components, notably anaerobes (obligate or facultative anaerobes, could be valuable biomarkers of lung function improvement under ivacaftor, and could shed light on the pathophysiology of lung disease in CF patients.

  8. Age dependence of myosin heavy chain transitions induced by creatine depletion in rat skeletal muscle

    Science.gov (United States)

    Adams, Gregory R.; Baldwin, Kenneth M.

    1995-01-01

    This study was designed to test the hypothesis that myosin heavy chain (MHC) plasticity resulting from creatine depletion is an age-dependent process. At weaning (age 28 days), rat pups were placed on either standard rat chow (normal diet juvenile group) or the same chow supplemented with 1% wt/wt of the creatine analogue beta-guanidinopropionic acid (creatine depletion juvenile (CDJ) group). Two groups of adult rats (age approximately 8 wk) were placed on the same diet regimens (normal diet adult and creatine depletion adult (CDA) groups). After 40 days (CDJ and normal diet juvenile groups) and 60 days (CDA and normal diet adult groups), animals were killed and several skeletal muscles were removed for analysis of creatine content or MHC ditribution. In the CDJ group, creatine depletion (78%) was accompanied by significant shifts toward expression of slower MHC isoforms in two slow and three fast skeletal muscles. In contrast, creatine depletion in adult animals did not result in similar shifts toward slow MHC isoform expression in either muscle type. The results of this study indicate that there is a differential effect of creatine depletion on MHC tranitions that appears to be age dependent. These results strongly suggest that investigators contemplating experimental designs involving the use of the creatine analogue beta-guanidinopropionic acid should consider the age of the animals to be used.

  9. Effects of stochastic noise on a three-dimensional Monte Carlo depletion analysis of the H.B. Robinson reactor

    International Nuclear Information System (INIS)

    Monte Carlo depletion calculations for nuclear reactors are affected by the presence of stochastic noise in the local flux estimates produced during the calculation. The effects of this random noise and its propagation between timesteps during long depletion simulations are not well understood. To improve this understanding, a series of Monte Carlo depletion simulations have been conducted for a 3-D, eighth-core model of the H.B. Robinson PWR. The studies were performed by using the in-line depletion capability of the MC21 Monte Carlo code to produce multiple independent depletion simulations. Global and local results from each simulation are compared in order to determine the variance among the different depletion realizations. These comparisons indicate that global quantities, such as eigenvalue (keff), do not tend to diverge among the independent depletion calculations. However, local quantities, such as fuel concentration, can deviate wildly between independent depletion realizations, especially at high burnup levels. Analysis and discussion of the results from the study are provided, along with several new observations regarding the propagation of random noise during Monte Carlo depletion calculations. (author)

  10. Structure and Depletion at Fluoro- and Hydro-carbon/Water Liquid/Liquid Interfaces

    OpenAIRE

    Kashimoto, Kaoru; Yoon, Jaesung; Hou, Binyang; Chen, Chiu-hao; Lin, Binhua; Aratono, Makoto; Takiue, Takanori; Schlossman, Mark L.

    2008-01-01

    The results of x-ray reflectivity studies of two oil/water (liquid/liquid) interfaces are inconsistent with recent predictions of the presence of a vapor-like depletion region at hydrophobic/aqueous interfaces. One of the oils, perfluorohexane, is a fluorocarbon whose super-hydrophobic interface with water provides a stringent test for the presence of a depletion layer. The other oil, heptane, is a hydrocarbon and, therefore, is more relevant to the study of biomolecular hydrophobicity. These...

  11. The Metabolome of Chlamydomonas reinhardtii following Induction of Anaerobic H2 Production by Sulfur Depletion*

    OpenAIRE

    Timmins, Matthew; Zhou, Wenxu; Rupprecht, Jens; Lim, Lysha; Thomas-Hall, Skye R.; Doebbe, Anja; Kruse, Olaf; Hankamer, Ben; Marx, Ute C.; Smith, Steven M.; Schenk, Peer M.

    2009-01-01

    The metabolome of the model species Chlamydomonas reinhardtii has been analyzed during 120 h of sulfur depletion to induce anaerobic hydrogen (H2) production, using NMR spectroscopy, gas chromatography coupled to mass spectrometry, and TLC. The results indicate that these unicellular green algae consume freshly supplied acetate in the medium to accumulate energy reserves during the first 24 h of sulfur depletion. In addition to the previously reported accumulation of starch, large amounts of ...

  12. Depletions at Browns Park National Wildlife Refuge [Draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Estimated depletion associated with the operation of Spitzie Marsh in Browns Park National Wildlife Refuge. Attached are the methods used to estimate depletion....

  13. Lithium Depletion in Fully Convective Pre-Main Sequence Stars

    CERN Document Server

    Bildsten, L; Matzner, C D; Ushomirsky, G; Bildsten, Lars; Brown, Edward F.; Matzner, Christopher D.; Ushomirsky, Greg

    1996-01-01

    We present an analytic calculation of the thermonuclear depletion of lithium in contracting, fully convective, pre-main sequence stars of mass M 0.08 M_sun) and for constraining the masses of lithium depleted stars.

  14. Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Phadke, Manali; Krynetskaia, Natalia [Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Mishra, Anurag [Jayne Haines Center for Pharmacogenomics, Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Krynetskiy, Evgeny, E-mail: ekrynets@temple.edu [Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Jayne Haines Center for Pharmacogenomics, Temple University School of Pharmacy, Philadelphia, PA 19140 (United States)

    2011-07-29

    Highlights: {yields} We examined the effect of glyceraldehyde 3-phosphate (GAPDH) depletion on proliferation of human carcinoma A549 cells. {yields} GAPDH depletion induces accelerated senescence in tumor cells via AMPK network, in the absence of DNA damage. {yields} Metabolic and genetic rescue experiments indicate that GAPDH has regulatory functions linking energy metabolism and cell cycle. {yields} Induction of senescence in LKB1-deficient lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation. -- Abstract: Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-{beta}-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of {alpha} subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

  15. Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

    International Nuclear Information System (INIS)

    Highlights: → We examined the effect of glyceraldehyde 3-phosphate (GAPDH) depletion on proliferation of human carcinoma A549 cells. → GAPDH depletion induces accelerated senescence in tumor cells via AMPK network, in the absence of DNA damage. → Metabolic and genetic rescue experiments indicate that GAPDH has regulatory functions linking energy metabolism and cell cycle. → Induction of senescence in LKB1-deficient lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation. -- Abstract: Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-β-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of α subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

  16. 26 CFR 1.642(e)-1 - Depreciation and depletion.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Depreciation and depletion. 1.642(e)-1 Section 1... (CONTINUED) INCOME TAXES Estates, Trusts, and Beneficiaries § 1.642(e)-1 Depreciation and depletion. An estate or trust is allowed the deductions for depreciation and depletion, but only to the extent...

  17. Inhibition of lytic infection of pseudorabies virus by arginine depletion

    International Nuclear Information System (INIS)

    Pseudorabies virus (PRV) is a member of Alphahepesviruses; it is an enveloped virus with a double-stranded DNA genome. Polyamines (such as spermine and spermidine) are ubiquitous in animal cells and participate in cellular proliferation and differentiation. Previous results of our laboratory showed that the PRV can accomplish lytic infection either in the presence of exogenous spermine (or spermidine) or depletion of cellular polyamines. The amino acid arginine is a precursor of polyamine biosynthesis. In this work, we investigated the role of arginine in PRV infection. It was found that the plaque formation of PRV was inhibited by arginase (enzyme catalyzing the conversion of arginine into ornithine and urea) treatment whereas this inhibition can be reversed by exogenous arginine, suggesting that arginine is essential for PRV proliferation. Western blotting was conducted to study the effect of arginine depletion on the levels of structural proteins of PRV in virus-infected cells. Four PRV structural proteins (gB, gE, UL47, and UL48) were chosen for examination, and results revealed that the levels of viral proteins were obviously reduced in long time arginase treatment. However, the overall protein synthesis machinery was apparently not influenced by arginase treatment either in mock or PRV-infected cells. Analyzing with native gel, we found that arginase treatment affected the mobility of PRV structural proteins, suggesting the conformational change of viral proteins by arginine depletion. Heat shock proteins, acting as molecular chaperons, participate in protein folding and translocation. Our results demonstrated that long time arginase treatment could reduce the expression of cellular heat shock proteins 70 (hsc70 and hsp70), and transcriptional suppression of heat shock protein 70 gene promoter was one of the mechanisms involved in this reduced expression

  18. Depletions of Elements from the Gas Phase: A Guide on Dust Compositions

    CERN Document Server

    Jenkins, Edward B

    2014-01-01

    Ultraviolet spectra of stars recorded by orbiting observatories since the 1970's have revealed absorption features produced by atoms in their favored ionization stages in the neutral ISM of our Galaxy. Most elements show abundances relative to hydrogen that are below their values in stars, indicating their removal by condensation into solid form. The relative amounts of these depletions vary from one location to the next, and different elements show varying degrees of depletion. In a study of abundances along 243 different sight lines reported in more than 100 papers, Jenkins (2009) characterized the systematic patterns for the depletions of 17 different elements, and these results in turn were used to help us understand the compositions of dust grains. Since the conclusions are based on differential depletions along different sightlines, they are insensitive to errors in the adopted values for the total element abundances. Some of the more remarkable conclusions to emerge from this study are that (1) oxygen ...

  19. Model of transit time for SiGe HBT Collector junction depletion-layer

    Institute of Scientific and Technical Information of China (English)

    Hu Hui-Yong; Zhang He-Ming; Dai Xian-Ying; Jia Xin-Zhang; Cui Xiao-Ying; Wang Wei; Ou Jian-Feng; Wang Xi-Yuan

    2005-01-01

    The transit time through collector junction depletion-layer is an important parameter that influences AC gain and frequency performance. In SiGe heterojunction bipolar transistor (HBT) collector junction, the depletion-layer width is given in three cases. The models of collector depletion-layer transit time, considering the collector current densities and base extension effect, are established and simulated using MATLAB. The influence of the different collector j unction bias voltage, collector concentration of As or P dopant and collector width on collector junction transit time is quantitatively studied. When the collector junction bias voltage, collector doping concentration and collector width are large, the transit time is quite long. And, from the results of simulations, the influence of the collector depletion-layer transit time on frequency performance is considerable in SiGe HBT with a thin base, so it could not be ignored.

  20. Effects of grain size and strain rate on compressive behavior for depleted uranium

    International Nuclear Information System (INIS)

    The compressive stress-strain curves of depleted uranium with different grain sizes were obtained over a wide range of strain rates ranging from 10-3 S-1 to 103 S-1 by static compression test and split Hopkinson pressure bar (SHPB) apparatus, combined with strain frozen technique and optical micrography, the effects of grain size and strain rate on compressive behavior for depleted uranium were discussed. Results show that twinning is the dominant deformation mechanism at the early deformation stage, and the coadjustment and fragmentation of grains are the dominant mechanism when deformation continues. Twinning possess is the major contribution and has lower strength when grain size is larger. Two kinds of depleted uranium with different grain sizes has strong' strain rate sensitivity, the number of activated twining systems is smaller when the strain rate is getting higher. Finally, a special form of the Johnson-Cook model was used to describe the mechanical response for depleted uranium. (authors)