Determination of CFTR densities in erythrocyte plasma membranes using recognition imaging

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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.

Conserved allosteric hot spots in the transmembrane domains of cystic fibrosis transmembrane conductance regulator (CFTR) channels and multidrug resistance protein (MRP) pumps.

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Wei, Shipeng; Roessler, Bryan C; Chauvet, Sylvain; Guo, Jingyu; Hartman, John L; Kirk, Kevin L

2014-07-18

ATP-binding cassette (ABC) transporters are an ancient family of transmembrane proteins that utilize ATPase activity to move substrates across cell membranes. The ABCC subfamily of the ABC transporters includes active drug exporters (the multidrug resistance proteins (MRPs)) and a unique ATP-gated ion channel (cystic fibrosis transmembrane conductance regulator (CFTR)). The CFTR channel shares gating principles with conventional ligand-gated ion channels, but the allosteric network that couples ATP binding at its nucleotide binding domains (NBDs) with conformational changes in its transmembrane helices (TMs) is poorly defined. It is also unclear whether the mechanisms that govern CFTR gating are conserved with the thermodynamically distinct MRPs. Here we report a new class of gain of function (GOF) mutation of a conserved proline at the base of the pore-lining TM6. Multiple substitutions of this proline promoted ATP-free CFTR activity and activation by the weak agonist, 5'-adenylyl-β,γ-imidodiphosphate (AMP-PNP). TM6 proline mutations exhibited additive GOF effects when combined with a previously reported GOF mutation located in an outer collar of TMs that surrounds the pore-lining TMs. Each TM substitution allosterically rescued the ATP sensitivity of CFTR gating when introduced into an NBD mutant with defective ATP binding. Both classes of GOF mutations also rescued defective drug export by a yeast MRP (Yor1p) with ATP binding defects in its NBDs. We conclude that the conserved TM6 proline helps set the energy barrier to both CFTR channel opening and MRP-mediated drug efflux and that CFTR channels and MRP pumps utilize similar allosteric mechanisms for coupling conformational changes in their translocation pathways to ATP binding at their NBDs. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

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.

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.

CFTR-France, a national relational patient database for sharing genetic and phenotypic data associated with rare CFTR variants.

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Claustres, Mireille; Thèze, Corinne; des Georges, Marie; Baux, David; Girodon, Emmanuelle; Bienvenu, Thierry; Audrezet, Marie-Pierre; Dugueperoux, Ingrid; Férec, Claude; Lalau, Guy; Pagin, Adrien; Kitzis, Alain; Thoreau, Vincent; Gaston, Véronique; Bieth, Eric; Malinge, Marie-Claire; Reboul, Marie-Pierre; Fergelot, Patricia; Lemonnier, Lydie; Mekki, Chadia; Fanen, Pascale; Bergougnoux, Anne; Sasorith, Souphatta; Raynal, Caroline; Bareil, Corinne

2017-10-01

Most of the 2,000 variants identified in the CFTR (cystic fibrosis transmembrane regulator) gene are rare or private. Their interpretation is hampered by the lack of available data and resources, making patient care and genetic counseling challenging. We developed a patient-based database dedicated to the annotations of rare CFTR variants in the context of their cis- and trans-allelic combinations. Based on almost 30 years of experience of CFTR testing, CFTR-France (https://cftr.iurc.montp.inserm.fr/cftr) currently compiles 16,819 variant records from 4,615 individuals with cystic fibrosis (CF) or CFTR-RD (related disorders), fetuses with ultrasound bowel anomalies, newborns awaiting clinical diagnosis, and asymptomatic compound heterozygotes. For each of the 736 different variants reported in the database, patient characteristics and genetic information (other variations in cis or in trans) have been thoroughly checked by a dedicated curator. Combining updated clinical, epidemiological, in silico, or in vitro functional data helps to the interpretation of unclassified and the reassessment of misclassified variants. This comprehensive CFTR database is now an invaluable tool for diagnostic laboratories gathering information on rare variants, especially in the context of genetic counseling, prenatal and preimplantation genetic diagnosis. CFTR-France is thus highly complementary to the international database CFTR2 focused so far on the most common CF-causing alleles. © 2017 Wiley Periodicals, Inc.

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

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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 mutant CFTR genotypes 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. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

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

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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.

Regulatory crosstalk by protein kinases on CFTR trafficking and activity

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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.

CFTR mediates noradrenaline-induced ATP efflux from DRG neurons.

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Kanno, Takeshi; Nishizaki, Tomoyuki

2011-09-24

In our earlier study, noradrenaline (NA) stimulated ATP release from dorsal root ganglion (DRG) neurons as mediated via β(3) adrenoceptors linked to G(s) protein involving protein kinase A (PKA) activation, to cause allodynia. The present study was conducted to understand how ATP is released from DRG neurons. In an outside-out patch-clamp configuration from acutely dissociated rat DRG neurons, single-channel currents, sensitive to the P2X receptor inhibitor PPADS, were evoked by approaching the patch-electrode tip close to a neuron, indicating that ATP is released from DRG neurons, to activate P2X receptor. NA increased the frequency of the single-channel events, but such NA effect was not found for DRG neurons transfected with the siRNA to silence the cystic fibrosis transmembrane conductance regulator (CFTR) gene. In the immunocytochemical study using acutely dissociated rat DRG cells, CFTR was expressed in neurons alone, but not satellite cells, fibroblasts, or Schwann cells. It is concluded from these results that CFTR mediates NA-induced ATP efflux from DRG neurons as an ATP channel.

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

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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.

CFTR, Mucins, and Mucus Obstruction in Cystic Fibrosis

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Kreda, Silvia M.; Davis, C. William; Rose, Mary Callaghan

2012-01-01

Mucus pathology in cystic fibrosis (CF) has been known for as long as the disease has been recognized and is sometimes called mucoviscidosis. The disease is marked by mucus hyperproduction and plugging in many organs, which are usually most fatal in the airways of CF patients, once the problem of meconium ileus at birth is resolved. After the CF gene, CFTR, was cloned and its protein product identified as a cAMP-regulated Cl− channel, causal mechanisms underlying the strong mucus phenotype of the disease became obscure. Here we focus on mucin genes and polymeric mucin glycoproteins, examining their regulation and potential relationships to a dysfunctional cystic fibrosis transmembrane conductance regulator (CFTR). Detailed examination of CFTR expression in organs and different cell types indicates that changes in CFTR expression do not always correlate with the severity of CF disease or mucus accumulation. Thus, the mucus hyperproduction that typifies CF does not appear to be a direct cause of a defective CFTR but, rather, to be a downstream consequence. In organs like the lung, up-regulation of mucin gene expression by inflammation results from chronic infection; however, in other instances and organs, the inflammation may have a non-infectious origin. The mucus plugging phenotype of the β-subunit of the epithelial Na+ channel (βENaC)-overexpressing mouse is proving to be an archetypal example of this kind of inflammation, with a dehydrated airway surface/concentrated mucus gel apparently providing the inflammatory stimulus. Data indicate that the luminal HCO3 − deficiency recently described for CF epithelia may also provide such a stimulus, perhaps by causing a mal-maturation of mucins as they are released onto luminal surfaces. In any event, the path between CFTR dysfunction and mucus hyperproduction has proven tortuous, and its unraveling continues to offer its own twists and turns, along with fascinating glimpses into biology. PMID:22951447

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

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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

Cholesterol modulates CFTR confinement in the plasma membrane of primary epithelial cells.

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Abu-Arish, Asmahan; Pandzic, Elvis; Goepp, Julie; Matthes, Elizabeth; Hanrahan, John W; Wiseman, Paul W

2015-07-07

The cystic fibrosis transmembrane conductance regulator (CFTR) is a plasma-membrane anion channel that, when mutated, causes the disease cystic fibrosis. Although CFTR has been detected in a detergent-resistant membrane fraction prepared from airway epithelial cells, suggesting that it may partition into cholesterol-rich membrane microdomains (lipid rafts), its compartmentalization has not been demonstrated in intact cells and the influence of microdomains on CFTR lateral mobility is unknown. We used live-cell imaging, spatial image correlation spectroscopy, and k-space image correlation spectroscopy to examine the aggregation state of CFTR and its dynamics both within and outside microdomains in the plasma membrane of primary human bronchial epithelial cells. These studies were also performed during treatments that augment or deplete membrane cholesterol. We found two populations of CFTR molecules that were distinguishable based on their dynamics at the cell surface. One population showed confinement and had slow dynamics that were highly cholesterol dependent. The other, more abundant population was less confined and diffused more rapidly. Treatments that deplete the membrane of cholesterol caused the confined fraction and average number of CFTR molecules per cluster to decrease. Elevating cholesterol had the opposite effect, increasing channel aggregation and the fraction of channels displaying confinement, consistent with CFTR recruitment into cholesterol-rich microdomains with dimensions below the optical resolution limit. Viral infection caused the nanoscale microdomains to fuse into large platforms and reduced CFTR mobility. To our knowledge, these results provide the first biophysical evidence for multiple CFTR populations and have implications for regulation of their surface expression and channel function. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

The CFTR-Associated Ligand Arrests the Trafficking of the Mutant ΔF508 CFTR Channel in the ER Contributing to Cystic Fibrosis

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Emily Bergbower

2018-01-01

Full Text Available Background/Aims: The CFTR-Associated Ligand (CAL, a PDZ domain containing protein with two coiled-coil domains, reduces cell surface WT CFTR through degradation in the lysosome by a well-characterized mechanism. However, CAL’s regulatory effect on ΔF508 CFTR has remained almost entirely uninvestigated. Methods: In this study, we describe a previously unknown pathway for CAL by which it regulates the membrane expression of ΔF508 CFTR through arrest of ΔF508 CFTR trafficking in the endoplasmic reticulum (ER using a combination of cell biology, biochemistry and electrophysiology. Results: We demonstrate that CAL is an ER localized protein that binds to ΔF508 CFTR and is degraded in the 26S proteasome. When CAL is inhibited, ΔF508 CFTR retention in the ER decreases and cell surface expression of mature functional ΔF508 CFTR is observed alongside of enhanced expression of plasma membrane scaffolding protein NHERF1. Chaperone proteins regulate this novel process, and ΔF508 CFTR binding to HSP40, HSP90, HSP70, VCP, and Aha1 changes to improve ΔF508 CFTR cell surface trafficking. Conclusion: Our results reveal a pathway in which CAL regulates the cell surface availability and intracellular retention of ΔF508 CFTR.

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

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

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LaRusch, Jessica; Jung, Jinsei; General, Ignacio J; Lewis, Michele D; Park, Hyun Woo; Brand, Randall E; Gelrud, Andres; Anderson, Michelle A; Banks, Peter A; Conwell, Darwin; Lawrence, Christopher; Romagnuolo, Joseph; Baillie, John; Alkaade, Samer; Cote, Gregory; Gardner, Timothy B; Amann, Stephen T; Slivka, Adam; Sandhu, Bimaljit; Aloe, Amy; Kienholz, Michelle L; Yadav, Dhiraj; Barmada, M Michael; Bahar, Ivet; Lee, Min Goo; Whitcomb, David C

2014-07-01

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 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 CFTR

Computational design of a PDZ domain peptide inhibitor that rescues CFTR activity.

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Kyle E Roberts

Full Text Available The cystic fibrosis transmembrane conductance regulator (CFTR is an epithelial chloride channel mutated in patients with cystic fibrosis (CF. The most prevalent CFTR mutation, ΔF508, blocks folding in the endoplasmic reticulum. Recent work has shown that some ΔF508-CFTR channel activity can be recovered by pharmaceutical modulators ("potentiators" and "correctors", but ΔF508-CFTR can still be rapidly degraded via a lysosomal pathway involving the CFTR-associated ligand (CAL, which binds CFTR via a PDZ interaction domain. We present a study that goes from theory, to new structure-based computational design algorithms, to computational predictions, to biochemical testing and ultimately to epithelial-cell validation of novel, effective CAL PDZ inhibitors (called "stabilizers" that rescue ΔF508-CFTR activity. To design the "stabilizers", we extended our structural ensemble-based computational protein redesign algorithm K* to encompass protein-protein and protein-peptide interactions. The computational predictions achieved high accuracy: all of the top-predicted peptide inhibitors bound well to CAL. Furthermore, when compared to state-of-the-art CAL inhibitors, our design methodology achieved higher affinity and increased binding efficiency. The designed inhibitor with the highest affinity for CAL (kCAL01 binds six-fold more tightly than the previous best hexamer (iCAL35, and 170-fold more tightly than the CFTR C-terminus. We show that kCAL01 has physiological activity and can rescue chloride efflux in CF patient-derived airway epithelial cells. Since stabilizers address a different cellular CF defect from potentiators and correctors, our inhibitors provide an additional therapeutic pathway that can be used in conjunction with current methods.

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

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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.

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

Restoration of CFTR function in patients with cystic fibrosis carrying the F508del-CFTR mutation.

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De Stefano, Daniela; Villella, Valeria R; Esposito, Speranza; Tosco, Antonella; Sepe, Angela; De Gregorio, Fabiola; Salvadori, Laura; Grassia, Rosa; Leone, Carlo A; De Rosa, Giuseppe; Maiuri, Maria C; Pettoello-Mantovani, Massimo; Guido, Stefano; Bossi, Anna; Zolin, Anna; Venerando, Andrea; Pinna, Lorenzo A; Mehta, Anil; Bona, Gianni; Kroemer, Guido; Maiuri, Luigi; Raia, Valeria

2014-01-01

Restoration of BECN1/Beclin 1-dependent autophagy and depletion of SQSTM1/p62 by genetic manipulation or autophagy-stimulatory proteostasis regulators, such as cystamine, have positive effects on mouse models of human cystic fibrosis (CF). These measures rescue the functional expression of the most frequent pathogenic CFTR mutant, F508del, at the respiratory epithelial surface and reduce lung inflammation in Cftr(F508del) homozygous mice. Cysteamine, the reduced form of cystamine, is an FDA-approved drug. Here, we report that oral treatment with cysteamine greatly reduces the mortality rate and improves the phenotype of newborn mice bearing the F508del-CFTR mutation. Cysteamine was also able to increase the plasma membrane expression of the F508del-CFTR protein in nasal epithelial cells from F508del homozygous CF patients, and these effects persisted for 24 h after cysteamine withdrawal. Importantly, this cysteamine effect after washout was further sustained by the sequential administration of epigallocatechin gallate (EGCG), a green tea flavonoid, both in vivo, in mice, and in vitro, in primary epithelial cells from CF patients. In a pilot clinical trial involving 10 F508del-CFTR homozygous CF patients, the combination of cysteamine and EGCG restored BECN1, reduced SQSTM1 levels and improved CFTR function from nasal epithelial cells in vivo, correlating with a decrease of chloride concentrations in sweat, as well as with a reduction of the abundance of TNF/TNF-alpha (tumor necrosis factor) and CXCL8 (chemokine [C-X-C motif] ligand 8) transcripts in nasal brushing and TNF and CXCL8 protein levels in the sputum. Altogether, these results suggest that optimal schedules of cysteamine plus EGCG might be used for the treatment of CF caused by the F508del-CFTR mutation.

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

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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.

Mechanisms of CFTR Functional Variants That Impair Regulated Bicarbonate Permeation and Increase Risk for Pancreatitis but Not for Cystic Fibrosis

OpenAIRE

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

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...

Gq activity- and β-arrestin-1 scaffolding-mediated ADGRG2/CFTR coupling are required for male fertility

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Lin, Hui; Li, Rui-Rui; Liang, Zong-Lai; Gao, Yuan; Yang, Zhao; He, Dong-Fang; Lin, Amy; Mo, Hui; Lu, Yu-Jing; Li, Meng-Jing; Kong, Wei; Chung, Ka Young; Yi, Fan; Li, Jian-Yuan; Qin, Ying-Ying; Li, Jingxin; Thomsen, Alex R B; Kahsai, Alem W; Chen, Zi-Jiang; Xu, Zhi-Gang; Liu, Mingyao

2018-01-01

Luminal fluid reabsorption plays a fundamental role in male fertility. We demonstrated that the ubiquitous GPCR signaling proteins Gq and β-arrestin-1 are essential for fluid reabsorption because they mediate coupling between an orphan receptor ADGRG2 (GPR64) and the ion channel CFTR. A reduction in protein level or deficiency of ADGRG2, Gq or β-arrestin-1 in a mouse model led to an imbalance in pH homeostasis in the efferent ductules due to decreased constitutive CFTR currents. Efferent ductule dysfunction was rescued by the specific activation of another GPCR, AGTR2. Further mechanistic analysis revealed that β-arrestin-1 acts as a scaffold for ADGRG2/CFTR complex formation in apical membranes, whereas specific residues of ADGRG2 confer coupling specificity for different G protein subtypes, this specificity is critical for male fertility. Therefore, manipulation of the signaling components of the ADGRG2-Gq/β-arrestin-1/CFTR complex by small molecules may be an effective therapeutic strategy for male infertility. PMID:29393851

CFTR Modulators: Shedding Light on Precision Medicine for Cystic Fibrosis

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Lopes-Pacheco, Miquéias

2016-01-01

Cystic fibrosis (CF) is the most common life-threatening monogenic disease afflicting Caucasian people. It affects the respiratory, gastrointestinal, glandular and reproductive systems. The major cause of morbidity and mortality in CF is the respiratory disorder caused by a vicious cycle of obstruction of the airways, inflammation and infection that leads to epithelial damage, tissue remodeling and end-stage lung disease. Over the past decades, life expectancy of CF patients has increased due to early diagnosis and improved treatments; however, these patients still present limited quality of life. Many attempts have been made to rescue CF transmembrane conductance regulator (CFTR) expression, function and stability, thereby overcoming the molecular basis of CF. Gene and protein variances caused by CFTR mutants lead to different CF phenotypes, which then require different treatments to quell the patients’ debilitating symptoms. In order to seek better approaches to treat CF patients and maximize therapeutic effects, CFTR mutants have been stratified into six groups (although several of these mutations present pleiotropic defects). The research with CFTR modulators (read-through agents, correctors, potentiators, stabilizers and amplifiers) has achieved remarkable progress, and these drugs are translating into pharmaceuticals and personalized treatments for CF patients. This review summarizes the main molecular and clinical features of CF, emphasizes the latest clinical trials using CFTR modulators, sheds light on the molecular mechanisms underlying these new and emerging treatments, and discusses the major breakthroughs and challenges to treating all CF patients. PMID:27656143

Structural basis of typhod: Salmonella typhi type IVb pilin (PilS) and cystic fibrosis transmembrane conductance regulator interaction

Energy Technology Data Exchange (ETDEWEB)

Balakrishna, A.; Saxena, A; Mok, H; Swaminathan, K

2009-01-01

The type IVb pilus of the enteropathogenic bacteria Salmonella typhi is a major adhesion factor during the entry of this pathogen into gastrointestinal epithelial cells. Its target of adhesion is a stretch of 10 residues from the first extracellular domain of cystic fibrosis transmembrane conductance regulator (CFTR). The crystal structure of the N-terminal 25 amino acid deleted S. typhi native PilS protein (PilS), which makes the pilus, was determined at 1.9 A resolution by the multiwavelength anomalous dispersion method. Also, the structure of the complex of PilS and a target CFTR peptide, determined at 1.8 A, confirms that residues 113-117 (NKEER) of CFTR are involved in binding with the pilin protein and gives us insight on the amino acids that are essential for binding. Furthermore, we have also explored the role of a conserved disulfide bridge in pilus formation. The subunit structure and assembly architecture are crucial for understanding pilus functions and designing suitable therapeutics against typhoid.

Structural basis of typhoid: Salmonella typhi type IVb pilin (PiLS) and cystic fibrosis transmembrane conductance regulator interaction

Energy Technology Data Exchange (ETDEWEB)

Balakrishna, A.M.; Saxena, A.; Mok, H. Y.-K.; Swaminathan, K.

2009-11-01

The type IVb pilus of the enteropathogenic bacteria Salmonella typhi is a major adhesion factor during the entry of this pathogen into gastrointestinal epithelial cells. Its target of adhesion is a stretch of 10 residues from the first extracellular domain of cystic fibrosis transmembrane conductance regulator (CFTR). The crystal structure of the N-terminal 25 amino acid deleted S. typhi native PilS protein ({Delta}PilS), which makes the pilus, was determined at 1.9 {angstrom} resolution by the multiwavelength anomalous dispersion method. Also, the structure of the complex of {Delta}PilS and a target CFTR peptide, determined at 1.8 {angstrom}, confirms that residues 113-117 (NKEER) of CFTR are involved in binding with the pilin protein and gives us insight on the amino acids that are essential for binding. Furthermore, we have also explored the role of a conserved disulfide bridge in pilus formation. The subunit structure and assembly architecture are crucial for understanding pilus functions and designing suitable therapeutics against typhoid.

Structural Basis of Typhoid: Salmonella typhi Type IVb pilin (PilS) and Cystic Fibrosis Transmembrane Conductance Regulatory Interaction

Energy Technology Data Exchange (ETDEWEB)

Balakrishna, A.; Saxena, A; Mok, H; Swaminathan, K

2009-01-01

The type IVb pilus of the enteropathogenic bacteria Salmonella typhi is a major adhesion factor during the entry of this pathogen into gastrointestinal epithelial cells. Its target of adhesion is a stretch of 10 residues from the first extracellular domain of cystic fibrosis transmembrane conductance regulator (CFTR). The crystal structure of the N-terminal 25 amino acid deleted S. typhi native PilS protein (PilS), which makes the pilus, was determined at 1.9 A resolution by the multiwavelength anomalous dispersion method. Also, the structure of the complex of PilS and a target CFTR peptide, determined at 1.8 A, confirms that residues 113-117 (NKEER) of CFTR are involved in binding with the pilin protein and gives us insight on the amino acids that are essential for binding. Furthermore, we have also explored the role of a conserved disulfide bridge in pilus formation. The subunit structure and assembly architecture are crucial for understanding pilus functions and designing suitable therapeutics against typhoid.

The HDAC inhibitor SAHA does not rescue CFTR membrane expression in Cystic Fibrosis.

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Bergougnoux, Anne; Petit, Aurélie; Knabe, Lucie; Bribes, Estelle; Chiron, Raphaël; De Sario, Albertina; Claustres, Mireille; Molinari, Nicolas; Vachier, Isabelle; Taulan-Cadars, Magali; Bourdin, Arnaud

2017-07-01

The development of suitable Cystic Fibrosis (CF) models for preclinical bench tests of therapeutic candidates is challenging. Indeed, the validation of molecules to rescue the p.Phe508del-CFTR channel (encoded by the Cystic Fibrosis Transmembrane conductance Regulator gene carrying the p.Phe508del mutation) requires taking into account their overall effects on the epithelium. Suberoylanilide Hydroxamic Acid (SAHA), a histone deacetylase inhibitor (HDACi), was previously shown to be a CFTR corrector via proteostasis modulation in CFTR-deficient immortalized cells. Here, we tested SAHA effects on goblet cell metaplasia using an ex vivo model based on the air-liquid interface (ALI) culture of differentiated airway epithelial cells obtained by nasal scraping from CF patients and healthy controls. Ex vivo epithelium grew successfully in ALI cultures with significant rise in the expression of CFTR and of markers of airway epithelial differentiation compared to monolayer cell culture. SAHA decreased CFTR transcript and protein levels in CF and non-CF epithelia. Whereas SAHA induced lysine hyperacetylation, it did not change histone modifications at the CFTR promoter. SAHA reduced MUC5AC and MUC5B expression and inhibited goblet epithelial cell differentiation. Similar effects were obtained in CF and non-CF epithelia. All the effects were fully reversible within five days from SAHA withdrawal. We conclude that, ex vivo, SAHA modulate the structure of airway epithelia without specific effect on CFTR gene and protein suggesting that HDACi cannot be useful for CF treatment. Copyright © 2017. Published by Elsevier Ltd.

Cellular chloride and bicarbonate retention alters intracellular pH regulation in Cftr KO crypt epithelium.

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Walker, Nancy M; Liu, Jinghua; Stein, Sydney R; Stefanski, Casey D; Strubberg, Ashlee M; Clarke, Lane L

2016-01-15

Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR), an anion channel providing a major pathway for Cl(-) and HCO3 (-) efflux across the apical membrane of the epithelium. In the intestine, CF manifests as obstructive syndromes, dysbiosis, inflammation, and an increased risk for gastrointestinal cancer. Cftr knockout (KO) mice recapitulate CF intestinal disease, including intestinal hyperproliferation. Previous studies using Cftr KO intestinal organoids (enteroids) indicate that crypt epithelium maintains an alkaline intracellular pH (pHi). We hypothesized that Cftr has a cell-autonomous role in downregulating pHi that is incompletely compensated by acid-base regulation in its absence. Here, 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein microfluorimetry of enteroids showed that Cftr KO crypt epithelium sustains an alkaline pHi and resistance to cell acidification relative to wild-type. Quantitative real-time PCR revealed that Cftr KO enteroids exhibit downregulated transcription of base (HCO3 (-))-loading proteins and upregulation of the basolateral membrane HCO3 (-)-unloader anion exchanger 2 (Ae2). Although Cftr KO crypt epithelium had increased Ae2 expression and Ae2-mediated Cl(-)/HCO3 (-) exchange with maximized gradients, it also had increased intracellular Cl(-) concentration relative to wild-type. Pharmacological reduction of intracellular Cl(-) concentration in Cftr KO crypt epithelium normalized pHi, which was largely Ae2-dependent. We conclude that Cftr KO crypt epithelium maintains an alkaline pHi as a consequence of losing both Cl(-) and HCO3 (-) efflux, which impairs pHi regulation by Ae2. Retention of Cl(-) and an alkaline pHi in crypt epithelium may alter several cellular processes in the proliferative compartment of Cftr KO intestine. Copyright © 2016 the American Physiological Society.

Cellular chloride and bicarbonate retention alters intracellular pH regulation in Cftr KO crypt epithelium

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Walker, Nancy M.; Liu, Jinghua; Stein, Sydney R.; Stefanski, Casey D.; Strubberg, Ashlee M.

2015-01-01

Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR), an anion channel providing a major pathway for Cl− and HCO3− efflux across the apical membrane of the epithelium. In the intestine, CF manifests as obstructive syndromes, dysbiosis, inflammation, and an increased risk for gastrointestinal cancer. Cftr knockout (KO) mice recapitulate CF intestinal disease, including intestinal hyperproliferation. Previous studies using Cftr KO intestinal organoids (enteroids) indicate that crypt epithelium maintains an alkaline intracellular pH (pHi). We hypothesized that Cftr has a cell-autonomous role in downregulating pHi that is incompletely compensated by acid-base regulation in its absence. Here, 2′,7′-bis(2-carboxyethyl)-5(6)-carboxyfluorescein microfluorimetry of enteroids showed that Cftr KO crypt epithelium sustains an alkaline pHi and resistance to cell acidification relative to wild-type. Quantitative real-time PCR revealed that Cftr KO enteroids exhibit downregulated transcription of base (HCO3−)-loading proteins and upregulation of the basolateral membrane HCO3−-unloader anion exchanger 2 (Ae2). Although Cftr KO crypt epithelium had increased Ae2 expression and Ae2-mediated Cl−/HCO3− exchange with maximized gradients, it also had increased intracellular Cl− concentration relative to wild-type. Pharmacological reduction of intracellular Cl− concentration in Cftr KO crypt epithelium normalized pHi, which was largely Ae2-dependent. We conclude that Cftr KO crypt epithelium maintains an alkaline pHi as a consequence of losing both Cl− and HCO3− efflux, which impairs pHi regulation by Ae2. Retention of Cl− and an alkaline pHi in crypt epithelium may alter several cellular processes in the proliferative compartment of Cftr KO intestine. PMID:26542396

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.

CFTR Genotype and Maximal Exercise Capacity in Cystic Fibrosis: A Cross-sectional Study.

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Radtke, Thomas; Hebestreit, Helge; Gallati, Sabina; Schneiderman, Jane E; Braun, Julia; Stevens, Daniel; Hulzebos, Erik Hj; Takken, Tim; Boas, Steven R; Urquhart, Don S; Lands, Larry C; Tejero, Sergio; Sovtic, Aleksandar; Dwyer, Tiffany; Petrovic, Milos; Harris, Ryan A; Karila, Chantal; Savi, Daniela; Usemann, Jakob; Mei-Zahav, Meir; Hatziagorou, Elpis; Ratjen, Felix; Kriemler, Susi

2018-02-01

Cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in human skeletal muscle cells. Variations of CFTR dysfunction among patients with cystic fibrosis may be an important determinant of maximal exercise capacity in cystic fibrosis. Previous studies on the relationship between CFTR genotype and maximal exercise capacity are scarce and contradictory. This study was designed to explore factors influencing maximal exercise capacity, expressed as peak oxygen uptake (V.O2peak), with a specific focus on CFTR genotype in children and adults with cystic fibrosis. In an international, multicenter, cross-sectional study, we collected data on CFTR genotype and cardiopulmonary exercise tests in patients with cystic fibrosis who were ages 8 years and older. CFTR mutations were classified into functional classes I–V. The final analysis included 726 patients (45% females; age range, 8–61 yr; forced expiratory volume in 1 s, 16 to 123% predicted) from 17 cystic fibrosis centers in North America, Europe, Australia, and Asia, all of whom had both valid maximal cardiopulmonary exercise tests and complete CFTR genotype data. Overall, patients exhibited exercise intolerance (V.O2peak, 77.3 ± 19.1% predicted), but values were comparable among different CFTR classes. We did not detect an association between CFTR genotype functional classes I–III and either V.O2peak (percent predicted) (adjusted β = −0.95; 95% CI, −4.18 to 2.29; P = 0.57) or maximum work rate (Wattmax) (adjusted β = −1.38; 95% CI, −5.04 to 2.27; P = 0.46) compared with classes IV–V. Those with at least one copy of a F508del-CFTR mutation and one copy of a class V mutation had a significantly lower V.O2peak (β = −8.24%; 95% CI, −14.53 to −2.99; P = 0.003) and lower Wattmax (adjusted β = −7.59%; 95% CI, −14.21 to −0.95; P = 0.025) than those with two copies of a class II mutation. On the basis of linear regression analysis adjusted for

Activation of CFTR by ASBT-mediated bile salt absorption

NARCIS (Netherlands)

Bijvelds, MJC; Jorna, H; Verkade, HJ; Bot, AGM; Hofmann, F; Agellon, LB; Sinaasappel, M; de Jonge, HR

2005-01-01

In cholangiocytes, bile salt (BS) uptake via the apical sodium-dependent bile acid transporter (ASBT) may evoke ductular flow by enhancing cAMP-mediated signaling to the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel. We considered that ASBT-mediated BS uptake in the distal

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

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Naziha Bakouh

Full Text Available 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.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.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 phosphate homeostasis.

The cystic fibrosis transmembrane recruiter the alter ego of CFTR as a multi-kinase anchor.

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Mehta, Anil

2007-11-01

This review focuses on a newly discovered interaction between protein kinases involved in cellular energetics, a process that may be disturbed in cystic fibrosis for unknown reasons. I propose a new model where kinase-mediated cellular transmission of energy provides mechanistic insight to a latent role of the cystic fibrosis transmembrane conductance regulator (CFTR). I suggest that CFTR acts as a multi-kinase recruiter to the apical epithelial membrane. My group finds that, in the cytosol, two protein kinases involved in cell energy homeostasis, nucleoside diphosphate kinase (NDPK) and AMP-activated kinase (AMPK), bind one another. Preliminary data suggest that both can also bind CFTR (function unclear). The disrupted role of this CFTR-kinase complex as 'membrane transmitter to the cell' is proposed as an alternative paradigm to the conventional ion transport mediated and CFTR/chloride-centric view of cystic fibrosis pathogenesis. Chloride remains important, but instead, chloride-induced control of the phosphohistidine content of one kinase component (NDPK, via a multi-kinase complex that also includes a third kinase, CK2; formerly casein kinase 2). I suggest that this complex provides the necessary near-equilibrium conditions needed for efficient transmission of phosphate energy to proteins controlling cellular energetics. Crucially, a new role for CFTR as a kinase controller is proposed with ionic concentration acting as a signal. The model posits a regulatory control relay for energy sensing involving a cascade of protein kinases bound to CFTR.

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.

CFTR-dependent defect in alternatively-activated macrophages in cystic fibrosis.

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Tarique, Abdullah A; Sly, Peter D; Holt, Patrick G; Bosco, Anthony; Ware, Robert S; Logan, Jayden; Bell, Scott C; Wainwright, Claire E; Fantino, Emmanuelle

2017-07-01

The role of the macrophages in cystic fibrosis (CF) lung disease has been poorly studied. We hypothesized that alternatively activated M2 macrophages are abnormal in CF lung disease. Blood samples were collected from adults (n=13) children (n=27) with CF on admission for acute pulmonary exacerbation and when clinically stable. Monocytes were differentiated into macrophages and polarized into classical (M1) and alternatively-activated (M2) phenotypes, function determined ex-vivo and compared with healthy controls. In the absence of functional cystic fibrosis trans-membrane conductance regulator (CFTR), either naturally in patients with CF or induced with CFTR inhibitors, monocyte-derived macrophages do not respond to IL-13/IL-4, fail to polarize into M2s associated with a post-transcriptional failure to produce and express IL-13Rα1 on the macrophage surface Polarization to the M1 phenotype was unaffected. CFTR-dependent imbalance of macrophage phenotypes and functions could contribute to the exaggerated inflammatory response seen in CF lung disease. Copyright © 2017 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

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.

NM23 proteins: innocent bystanders or local energy boosters for CFTR?

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Muimo, Richmond; Alothaid, Hani Mm; Mehta, Anil

2018-03-01

NM23 proteins NDPK-A and -B bind to the cystic fibrosis (CF) protein CFTR in different ways from kinases such as PKA, CK2 and AMPK or linkers to cell calcium such as calmodulin and annexins. NDPK-A (not -B) interacts with CFTR through reciprocal AMPK binding/control, whereas NDPK-B (not -A) binds directly to CFTR. NDPK-B can activate G proteins without ligand-receptor coupling, so perhaps NDPK-B's binding influences energy supply local to a nucleotide-binding site (NBD1) needed for CFTR to function. Curiously, CFTR (ABC-C7) is a member of the ATP-binding cassette (ABC) protein family that does not obey 'clan rules'; CFTR channels anions and is not a pump, regulates disparate processes, is itself regulated by multiple means and is so pleiotropic that it acts as a hub that orchestrates calcium signaling through its consorts such as calmodulin/annexins. Furthermore, its multiple partners make CFTR dance to different tunes in different cellular and subcellular locations as it recycles from the plasma membrane to endosomes. CFTR function in airway apical membranes is inhibited by smoking which has been dubbed 'acquired CF'. CFTR alone among family members possesses a trap for other proteins that it unfurls as a 'fish-net' and which bears consensus phosphorylation sites for many protein kinases, with PKA being the most canonical. Recently, the site of CFTR's commonest mutation has been proposed as a knock-in mutant that alters allosteric control of kinase CK2 by log orders of activity towards calmodulin and other substrates after CFTR fragmentation. This link from CK2 to calmodulin that binds the R region invokes molecular paths that control lumen formation, which is incomplete in the tracheas of some CF-affected babies. Thus, we are poised to understand the many roles of NDPK-A and -B in CFTR function and, especially lumen formation, which is defective in the gut and lungs of many CF babies.

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

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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.

Current insights into the role of PKA phosphorylation in CFTR channel activity and the pharmacological rescue of cystic fibrosis disease-causing mutants.

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Chin, Stephanie; Hung, Maurita; Bear, Christine E

2017-01-01

Cystic fibrosis transmembrane conductance regulator (CFTR) channel gating is predominantly regulated by protein kinase A (PKA)-dependent phosphorylation. In addition to regulating CFTR channel activity, PKA phosphorylation is also involved in enhancing CFTR trafficking and mediating conformational changes at the interdomain interfaces of the protein. The major cystic fibrosis (CF)-causing mutation is the deletion of phenylalanine at position 508 (F508del); it causes many defects that affect CFTR trafficking, stability, and gating at the cell surface. Due to the multiple roles of PKA phosphorylation, there is growing interest in targeting PKA-dependent signaling for rescuing the trafficking and functional defects of F508del-CFTR. This review will discuss the effects of PKA phosphorylation on wild-type CFTR, the consequences of CF mutations on PKA phosphorylation, and the development of therapies that target PKA-mediated signaling.

The molecular analysis of mutations in exons 4, 11 and 21 of the cystic fibrosis transmembrane conductance regulator (CFTR gene in cystic fibrosis patients in Kermanshah, Iran

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Nasibe Karimi

2017-03-01

Full Text Available Introduction: Cystic fibrosis (CF is a common genetic disorder in white populations with an autosomal recessive pattern, caused by mutations in the CFTR gene. The frequency of more than 1950 various mutations reported in the CFTR gene significantly varies in different populations. ∆F508 is a common mutation in exon 10, which is first addressed in the molecular analysis of the disease. Other exons are required to be investigated owing to failing to identify mutations in the patients. The present study was conducted to investigate mutations in exons 4, 11 and 21 of the CFTR gene using the sequencing method in CF patients in Kermanshah province, Iran. Methods: The present descriptive study was conducted on all patients with CF presenting to the medical genetics center in Kermanshah in 2010-2011. After taking blood samples and extracting DNA using saturated NaCl solution, sequences of exons were amplified using PCR and sequenced for identifying mutations. Results: The frequency of mutations was found to be respectively 0, 0 and 5.5% in exon 11, 21 and 4. The D110H mutation was found to be homozygous in one subject and heterozygous in another. Moreover, the 4029A>G polymorphism (12.9% was found to be homozygous in two subjects and heterozygous in three others. Conclusion: The D110H mutation is recommended to be included in the screening programs of the study population. The results obtained support the effects of ethnic and geographical factors on the distribution of CF mutations.

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

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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.

A New Targeted CFTR Mutation Panel Based on Next-Generation Sequencing Technology.

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Lucarelli, Marco; Porcaro, Luigi; Biffignandi, Alice; Costantino, Lucy; Giannone, Valentina; Alberti, Luisella; Bruno, Sabina Maria; Corbetta, Carlo; Torresani, Erminio; Colombo, Carla; Seia, Manuela

2017-09-01

Searching for mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR) is a key step in the diagnosis of and neonatal and carrier screening for cystic fibrosis (CF), and it has implications for prognosis and personalized therapy. The large number of mutations and genetic and phenotypic variability make this search a complex task. Herein, we developed, validated, and tested a laboratory assay for an extended search for mutations in CFTR using a next-generation sequencing-based method, with a panel of 188 CFTR mutations customized for the Italian population. Overall, 1426 dried blood spots from neonatal screening, 402 genomic DNA samples from various origins, and 1138 genomic DNA samples from patients with CF were analyzed. The assay showed excellent analytical and diagnostic operative characteristics. We identified and experimentally validated 159 (of 188) CFTR mutations. The assay achieved detection rates of 95.0% and 95.6% in two large-scale case series of CF patients from central and northern Italy, respectively. These detection rates are among the highest reported so far with a genetic test for CF based on a mutation panel. This assay appears to be well suited for diagnostics, neonatal and carrier screening, and assisted reproduction, and it represents a considerable advantage in CF genetic counseling. Copyright © 2017 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

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

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Geneviève Mailhot

2010-05-01

Full Text Available Abnormal fatty acid composition (FA in plasma and tissue lipids frequently occurs in homozygous and even in heterozygous carriers of cystic fibrosis transmembrane conductance regulator (CFTR mutations. The mechanism(s underlying these abnormalities remained, however, poorly understood despite the potentially CFTR contributing role.The aim of the present study was to investigate the impact of CFTR depletion on FA uptake, composition and metabolism using the intestinal Caco-2/15 cell line. shRNA-mediated cftr gene silencing induced qualitative and quantitative modifications in FA composition in differentiated enterocytes as determined by gas-liquid chromatography. With the cftr gene disruption, there was a 1,5 fold increase in the total FA amount, largely attributable to monounsaturated and saturated FA compared to controls. The activity of delta-7 desaturase, estimated by the 16:1(n-7/16:0, was significantly higher in knockdown cells and consistent with the striking elevation of the n-7 FA family. When incubated with [14C]-oleic acid, CFTR-depleted cells were capable of quick incorporation and export to the medium concomitantly with the high protein expression of L-FABP known to promote intracellular FA trafficking. Accordingly, lipoprotein vehicles (CM, VLDL, LDL and HDL, isolated from CFTR knockdown cells, exhibited higher levels of radiolabeled FA. Moreover, in the presence of [14C]-acetate, knockdown cells exhibited enhanced secretion of newly synthesized phospholipids, triglycerides, cholesteryl esters and free FA, thereby suggesting a stimulation of the lipogenic pathway. Conformably, gene expression of SREBP-1c, a key lipogenic transcription factor, was increased while protein expression of the phosphorylated and inactive form of acetylCoA carboxylase was reduced, confirming lipogenesis induction. Finally, CFTR-depleted cells exhibited lower gene expression of transcription factors (PPARalpha, LXRalpha, LXRbeta and RXRalpha

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

F508del-CFTR rescue: a matter of cell stress response.

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Nieddu, Erika; Pollarolo, Benedetta; Merello, Luisa; Schenone, Silvia; Mazzei, Mauro

2013-01-01

Cystic fibrosis (CF) is a common inherited fatal disease affecting 70,000 people worldwide, with a median predicted age of survival of approximately 38 years. The deletion of Phenylalanine in position 508 of the Cystic Fibrosis Transmembrane conductance Regulator (F508del-CFTR) is the most common mutation in CF patients: the deleted protein, not properly folded, is degraded. To date no commercial drugs are available. Low temperature, some osmolytes and conditions able to induce heat shock protein 70 (Hsp70) expression and heat shock cognate 70 (Hsc70) inhibition result in F508del-CFTR rescue, hence restoring its physiological function: this review sheds light on the correlation between these several evidences. Interestingly, all these approaches have a role in the cell stress response (CSR), a set of cell reactions to stress. In addition, unpredictably, F508del-CFTR rescue has to be considered in the frame of CSR: entities that induce - or are induced during - the CSR are, in general, also able to correct trafficking defect of CFTR. Specifically, the low temperature induces, by definition, a CSR; osmolytes, such as glycerol and trimethylamine N-oxide (TMAO), are products of the CSR; pharmacological correctors, such as Matrine and 4-phenylbutirric acid (4PBA), down-regulate the constitutive Hsc70 in favor of an up-regulation of the inducible chaperone Hsp70, another component of the CSR. The identification of a common mechanism of action for different types of correctors could drive the discovery of new active molecules in CF, overcoming methods clinically inapplicable, such as the low temperature.

Is congenital bilateral absence of vas deferens a primary form of cystic fibrosis? Analyses of the CFTR gene in 67 patients

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Mercier, B.; Verlingue, C.; Audrezet, M.P.; Ferec, C. [Centre de Biogenetique C.D.T.S., Brest (France); Lissens, W.; Bonduelle, M. [University Hospital VUB, Brussels (United Kingdom); Silber, S.J. [St. Luke`s Hospital, St. Louis, MO (United States); Novelli, G. [Catholic Univ. of Rome (Italy)

1995-01-01

Congenital bilateral absence of the vas deferens (CBAVD) is an important cause of sterility in men. Although the genetic basis of this condition is still unclear, it has been shown recently that some of these patients carry mutations in their cystic fibrosis transmembrane conductance regulator (CFTR) genes. To extend this observation, we have analyzed the entire coding sequence of the CFTR gene in a cohort of 67 men with CBAVD, who are otherwise healthy. We have identified four novel missense mutations (A800G, G149R, R258G, and E193K). We have shown that 42% of subjects were carriers of one CFTR allele and that 24% are compound heterozygous for CFTR alleles. Thus, we have been unable to identify 76% of these patients as carrying two CFTR mutations. Furthermore, we have described the segregation of CFTR haplotypes in the family of one CBAVD male; in this family are two male siblings, with identical CFTR loci but displaying different phenotypes, one of them being fertile and the other sterile. The data presented in this family, indicating a discordance between the CBAVD phenotype and a marked carrier ({delta}F508) chromosome, support the involvement of another gene(s), in the etiology of CBAVD. 35 refs., 2 figs., 1 tab.

CFTR is a tumor suppressor gene in murine and human intestinal cancer

NARCIS (Netherlands)

Than, B. L. N.; Linnekamp, J. F.; Starr, T. K.; Largaespada, D. A.; Rod, A.; Zhang, Y.; Bruner, V.; Abrahante, J.; Schumann, A.; Luczak, T.; Niemczyk, A.; O'Sullivan, M. G.; Medema, J. P.; Fijneman, R. J. A.; Meijer, G. A.; van den Broek, E.; Hodges, C. A.; Scott, P. M.; Vermeulen, L.; Cormier, R. T.

2016-01-01

CFTR, the cystic fibrosis (CF) gene, encodes for the CFTR protein that plays an essential role in anion regulation and tissue homeostasis of various epithelia. In the gastrointestinal (GI) tract CFTR promotes chloride and bicarbonate secretion, playing an essential role in ion and acid-base

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

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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

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

International Nuclear Information System (INIS)

Marasini, Carlotta; Galeno, Lauretta; Moran, Oscar

2012-01-01

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

Genotype-phenotype correlation and functional studies in patients with cystic fibrosis bearing CFTR complex alleles.

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Terlizzi, Vito; Castaldo, Giuseppe; Salvatore, Donatello; Lucarelli, Marco; Raia, Valeria; Angioni, Adriano; Carnovale, Vincenzo; Cirilli, Natalia; Casciaro, Rosaria; Colombo, Carla; Di Lullo, Antonella Miriam; Elce, Ausilia; Iacotucci, Paola; Comegna, Marika; Scorza, Manuela; Lucidi, Vincenzina; Perfetti, Anna; Cimino, Roberta; Quattrucci, Serena; Seia, Manuela; Sofia, Valentina Maria; Zarrilli, Federica; Amato, Felice

2017-04-01

The effect of complex alleles in cystic fibrosis (CF) is poorly defined for the lack of functional studies. To describe the genotype-phenotype correlation and the results of either in vitro and ex vivo studies performed on nasal epithelial cells (NEC) in a cohort of patients with CF carrying cystic fibrosis transmembrane conductance regulator ( CFTR ) complex alleles. We studied 70 homozygous, compound heterozygous or heterozygous for CFTR mutations: p.[Arg74Trp;Val201Met;Asp1270Asn], n=8; p.[Ile148Thr;Ile1023_Val1024del], n=5; p.[Arg117Leu;Leu997Phe], n=6; c.[1210-34TG[12];1210-12T[5];2930C>T], n=3; p.[Arg74Trp;Asp1270Asn], n=4; p.Asp1270Asn, n=2; p.Ile148Thr, n=6; p.Leu997Phe, n=36. In 39 patients, we analysed the CFTR gating activity on NEC in comparison with patients with CF (n=8) and carriers (n=4). Finally, we analysed in vitro the p.[Arg74Trp;Val201Met;Asp1270Asn] complex allele. The p.[Ile148Thr;Ile1023_Val1024del] caused severe CF in five compound heterozygous with a class I-II mutation. Their CFTR activity on NEC was comparable with patients with two class I-II mutations (mean 7.3% vs 6.9%). The p.[Arg74Trp;Asp1270Asn] and the p.Asp1270Asn have scarce functional effects, while p.[Arg74Trp;Val201Met;Asp1270Asn] caused mild CF in four of five subjects carrying a class I-II mutation in trans , or CFTR-related disorders (CFTR-RD) in three having in trans a class IV-V mutation. The p.[Arg74Trp;Val201Met;Asp1270Asn] causes significantly (pT] and a class I-II mutation had mild CF or CFTR-RD (gating activity: 18.5-19.0%). The effect of complex alleles partially depends on the mutation in trans . Although larger studies are necessary, the CFTR activity on NEC is a rapid contributory tool to classify patients with CFTR dysfunction. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Rab4GTPase modulates CFTR function by impairing channel expression at plasma membrane

International Nuclear Information System (INIS)

Saxena, Sunil K.; Kaur, Simarna; George, Constantine

2006-01-01

Cystic fibrosis (CF), an autosomal recessive disorder, is caused by the disruption of biosynthesis or the function of a membrane cAMP-activated chloride channel, CFTR. CFTR regulatory mechanisms include recruitment of channel proteins to the cell surface from intracellular pools and by protein-protein interactions. Rab proteins are small GTPases involved in regulated trafficking controlling vesicle docking and fusion. Rab4 controls recycling events from endosome to the plasma membrane, fusion, and degradation. The colorectal cell line HT-29 natively expresses CFTR and responds to cAMP stimulation with an increase in CFTR-mediated currents. Rab4 over-expression in HT-29 cells inhibits both basal and cAMP-stimulated CFTR-mediated currents. GTPase-deficient Rab4Q67L and GDP locked Rab4S22N both inhibit channel activity, which appears characteristically different. Active status of Rab4 was confirmed by GTP overlay assay, while its expression was verified by Western blotting. The pull-down and immunoprecipitation experiments suggest that Rab4 physically interacts with CFTR through protein-protein interaction. Biotinylation with cell impermeant NHS-Sulfo-SS-Biotin implies that Rab4 impairs CFTR expression at cell surface. The enhanced cytosolic CFTR indicates that Rab4 expression restrains CFTR appearance at the cell membrane. The study suggests that Rab4 regulates the channel through multiple mechanisms that include protein-protein interaction, GTP/GDP exchange, and channel protein trafficking. We propose that Rab4 is a dynamic molecule with a significant role in CFTR function

CFTR mutation analysis and haplotype associations in CF patients☆

OpenAIRE

Cordovado, S.K.; Hendrix, M.; Greene, C.N.; Mochal, S.; Earley, M.C.; Farrell, P.M.; Kharrazi, M.; Hannon, W.H.; Mueller, P.W.

2011-01-01

Most newborn screening (NBS) laboratories use second-tier molecular tests for cystic fibrosis (CF) using dried blood spots (DBS). The Centers for Disease Control and Prevention’s NBS Quality Assurance Program offers proficiency testing (PT) in DBS for CF transmembrane conductance regulator (CFTR) gene mutation detection. Extensive molecular characterization on 76 CF patients, family members or screen positive newborns was performed for quality assurance. The coding, regulatory regions and por...

Restoration of CFTR Activity in Ducts Rescues Acinar Cell Function and Reduces Inflammation in Pancreatic and Salivary Glands of Mice.

Science.gov (United States)

Zeng, Mei; Szymczak, Mitchell; Ahuja, Malini; Zheng, Changyu; Yin, Hongen; Swaim, William; Chiorini, John A; Bridges, Robert J; Muallem, Shmuel

2017-10-01

Sjögren's syndrome and autoimmune pancreatitis are disorders with decreased function of salivary, lacrimal glands, and the exocrine pancreas. Nonobese diabetic/ShiLTJ mice and mice transduced with the cytokine BMP6 develop Sjögren's syndrome and chronic pancreatitis and MRL/Mp mice are models of autoimmune pancreatitis. Cystic fibrosis transmembrane conductance regulator (CFTR) is a ductal Cl -  channel essential for ductal fluid and HCO 3 - secretion. We used these models to ask the following questions: is CFTR expression altered in these diseases, does correction of CFTR correct gland function, and most notably, does correcting ductal function correct acinar function? We treated the mice models with the CFTR corrector C18 and the potentiator VX770. Glandular, ductal, and acinar cells damage, infiltration, immune cells and function were measured in vivo and in isolated duct/acini. In the disease models, CFTR expression is markedly reduced. The salivary glands and pancreas are inflamed with increased fibrosis and tissue damage. Treatment with VX770 and, in particular, C18 restored salivation, rescued CFTR expression and localization, and nearly eliminated the inflammation and tissue damage. Transgenic overexpression of CFTR exclusively in the duct had similar effects. Most notably, the markedly reduced acinar cell Ca 2+ signaling, Orai1, inositol triphosphate receptors, Aquaporin 5 expression, and fluid secretion were restored by rescuing ductal CFTR. Our findings reveal that correcting ductal function is sufficient to rescue acinar cell function and suggests that CFTR correctors are strong candidates for the treatment of Sjögren's syndrome and pancreatitis. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Biophysical characterisation of calumenin as a charged F508del-CFTR folding modulator.

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Rashmi Tripathi

Full Text Available The cystic fibrosis transmembrane regulator (CFTR is a cyclic-AMP dependent chloride channel expressed at the apical surface of epithelial cells lining various organs such as the respiratory tract. Defective processing and functioning of this protein caused by mutations in the CFTR gene results in loss of ionic balance, defective mucus clearance, increased proliferation of biofilms and inflammation of human airways observed in cystic fibrosis (CF patients. The process by which CFTR folds and matures under the influence of various chaperones in the secretory pathway remains incompletely understood. Recently, calumenin, a secretory protein, belonging to the CREC family of low affinity calcium binding proteins has been identified as a putative CFTR chaperone whose biophysical properties and functions remain uncharacterized. We compared hydropathy, instability, charge, unfoldability, disorder and aggregation propensity of calumenin and other CREC family members with CFTR associated chaperones and calcium binding proteins, wild-type and mutant CFTR proteins and intrinsically disordered proteins (IDPs. We observed that calumenin, along with other CREC proteins, was significantly more charged and less folded compared to CFTR associated chaperones. Moreover like IDPs, calumenin and other CREC proteins were found to be less hydrophobic and aggregation prone. Phylogenetic analysis revealed a close link between calumenin and other CREC proteins indicating how evolution might have shaped their similar biophysical properties. Experimentally, calumenin was observed to significantly reduce F508del-CFTR aggregation in a manner similar to AavLEA1, a well-characterized IDP. Fluorescence microscopy based imaging analysis also revealed altered trafficking of calumenin in bronchial cells expressing F508del-CFTR, indicating its direct role in the pathophysiology of CF. In conclusion, calumenin is characterized as a charged protein exhibiting close similarity with

Stimulation of wild-type, F508del- and G551D-CFTR chloride channels by non toxic modified pyrrolo[2,3-b]pyrazine derivatives

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Luc eDannhoffer

2011-08-01

Full Text Available Cystic Fibrosis is a major inherited disorder involving abnormalities of fluid and electrolyte transport in a number of different organs due to abnormal function of Cystic Fibrosis Transmembrane conductance Regulator (CFTR protein. We recently identified a family of CFTR activators, which contains the hit: RP107 [7-n-butyl-6-(4-hydroxyphenyl[5H]-pyrrolo[2,3-b]pyrazine]. Here, we further evaluated the effect of the chemical modifications of the RP107-OH radical on CFTR activation. The replacement of the OH radical by a fluorine atom at position 2 (RP193 or 4 (RP185 significantly decreased the toxicity of the compounds without altering the ability to activate CFTR, especially for RP193. The non-toxic compound RP193 has no effect on cAMP production but stimulates the channel activity of wild-type CFTR in stably transfected CHO cells, in human bronchial epithelial NuLi-1 cells and in primary culture of human bronchial epithelial cells. Whole cell and single patch clamp recordings showed that RP193 induced a linear, time and voltage-independent current, which was fully inhibited by two different and selective CFTR inhibitors (CFTRinh-172 and GPinh-5a. Moreover, RP193 stimulates CFTR in temperature-rescued CuFi-1 (F508del/F508del human bronchial epithelial cells and in CHO cells stably expressing G551D-CFTR. This study shows that it is feasible to reduce cytotoxicity of chemical compounds without affecting their potency to activate CFTR and to rescue the class 2 F508del-CFTR and class 3 G551D-CFTR CF mutant activities.

Targeting a genetic defect: cystic fibrosis transmembrane conductance regulator modulators in cystic fibrosis

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Nico Derichs

2013-03-01

Full Text Available Cystic fibrosis (CF is caused by genetic mutations that affect the cystic fibrosis transmembrane conductance regulator (CFTR protein. These mutations can impact the synthesis and transfer of the CFTR protein to the apical membrane of epithelial cells, as well as influencing the gating or conductance of chloride and bicarbonate ions through the channel. CFTR dysfunction results in ionic imbalance of epithelial secretions in several organ systems, such as the pancreas, gastrointestinal tract, liver and the respiratory system. Since discovery of the CFTR gene in 1989, research has focussed on targeting the underlying genetic defect to identify a disease-modifying treatment for CF. Investigated management strategies have included gene therapy and the development of small molecules that target CFTR mutations, known as CFTR modulators. CFTR modulators are typically identified by high-throughput screening assays, followed by preclinical validation using cell culture systems. Recently, one such modulator, the CFTR potentiator ivacaftor, was approved as an oral therapy for CF patients with the G551D-CFTR mutation. The clinical development of ivacaftor not only represents a breakthrough in CF care but also serves as a noteworthy example of personalised medicine.

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

Science.gov (United States)

Yang, Hong; Xu, Li-na; He, Cheng-yan; Liu, Xin; Fang, Rou-yu; Ma, Tong-hui

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 I− 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 EC50 values of 73±1.4, 56±1.7, and 50±0.5μmol/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 stimulated 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 potentiators that stimulated colonic chloride and fluid secretion. Thus CFTR chloride channel is a molecular target of vegetable laxative drugs. PMID:21602836

From the endoplasmic reticulum to the plasma membrane: mechanisms of CFTR folding and trafficking.

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Farinha, Carlos M; Canato, Sara

2017-01-01

CFTR biogenesis starts with its co-translational insertion into the membrane of endoplasmic reticulum and folding of the cytosolic domains, towards the acquisition of a fully folded compact native structure. Efficiency of this process is assessed by the ER quality control system that allows the exit of folded proteins but targets unfolded/misfolded CFTR to degradation. If allowed to leave the ER, CFTR is modified at the Golgi and reaches the post-Golgi compartments to be delivered to the plasma membrane where it functions as a cAMP- and phosphorylation-regulated chloride/bicarbonate channel. CFTR residence at the membrane is a balance of membrane delivery, endocytosis, and recycling. Several adaptors, motor, and scaffold proteins contribute to the regulation of CFTR stability and are involved in continuously assessing its structure through peripheral quality control systems. Regulation of CFTR biogenesis and traffic (and its dysregulation by mutations, such as the most common F508del) determine its overall activity and thus contribute to the fine modulation of chloride secretion and hydration of epithelial surfaces. This review covers old and recent knowledge on CFTR folding and trafficking from its synthesis to the regulation of its stability at the plasma membrane and highlights how several of these steps can be modulated to promote the rescue of mutant CFTR.

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

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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.

A new compound heterozygous CFTR mutation in a Chinese family with cystic fibrosis.

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Xie, Yingjun; Huang, Xueqiong; Liang, Yujian; Xu, Lingling; Pei, Yuxin; Cheng, Yucai; Zhang, Lidan; Tang, Wen

2017-11-01

Cystic fibrosis (CF) is the most common autosomal recessive disease among Caucasians but is rarer in the Chinese population, because mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. To elucidate the causative role of a novel compound heterozygous mutation of CF. In this study, clinical samples were obtained from two siblings with recurrent airway infections, clubbed fingers, salt-sweat and failure to gain weight in a non-consanguineous Chinese family. Next-generation sequencing was performed on the 27 coding exons of CFTR in both children, with confirmation by Sanger sequencing. Next-generation sequencing showed the same compound heterozygous CFTR mutation (c.865A>T p.Arg289X and c.3651_3652insAAAT p.Tyr1219X) in both children. As this mutation is consistent with the clinical manifestations of CF and no other mutations were detected after scanning the gene sequence, we suggest that the CF phenotype is caused by compound heterozygosity for c.865A>T and c.3651_3652insAAAT. As c865A>T is not currently listed in the "Cystic Fibrosis Mutation Database", this information about CF in a Chinese population is of interest. © 2015 John Wiley & Sons Ltd.

Lipoxin A4 and platelet activating factor are involved in E. coli or LPS-induced lung inflammation in CFTR-deficient mice.

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Haiya Wu

Full Text Available CFTR (cystic fibrosis transmembrane conductance regulator is expressed by both neutrophils and platelets. Lack of functional CFTR could lead to severe lung infection and inflammation. Here, we found that mutation of CFTR (F508del or inhibition of CFTR in mice led to more severe thrombocytopenia, alveolar neutrocytosis and bacteriosis, and lower lipoxin A4/MIP-2 (macrophage inhibitory protein-2 or lipoxin A4/neutrophil ratios in the BAL (bronchoalveolar lavage during acute E. coli pneumonia. In vitro, inhibition of CFTR promotes MIP-2 production in LPS-stimulated neutrophils; however, lipoxin A4 could dose-dependently suppress this effect. In LPS-induced acute lung inflammation, blockade of PSGL-1 (P-selectin glycoprotein ligand-1 or P-selectin, antagonism of PAF by WEB2086, or correction of mutated CFTR trafficking by KM11060 could significantly increase plasma lipoxin A4 levels in F508del relevant to wildtype mice. Concurrently, F508del mice had higher plasma platelet activating factor (PAF levels and PAF-AH activity compared to wildtype under LPS challenge. Inhibiting hydrolysis of PAF by a specific PAF-AH (PAF-acetylhydrolase inhibitor, MAFP, could worsen LPS-induced lung inflammation in F508del mice compared to vehicle treated F508del group. Particularly, depletion of platelets in F508del mice could significantly decrease plasma lipoxin A4 and PAF-AH activity and deteriorate LPS-induced lung inflammation compared to control F508del mice. Taken together, lipoxin A4 and PAF are involved in E. coli or LPS-induced lung inflammation in CFTR-deficient mice, suggesting that lipoxin A4 and PAF might be therapeutic targets for ameliorating CFTR-deficiency deteriorated lung inflammation.

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

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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.

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

Full Text Available Low bone mass and increased fracture risk are recognized complications of cystic fibrosis (CF. CF-related bone disease (CFBD is characterized by uncoupled bone turnover--impaired osteoblastic bone formation and enhanced osteoclastic bone resorption. Intestinal malabsorption, vitamin D deficiency and inflammatory cytokines contribute to CFBD. However, epidemiological investigations and animal models also support a direct causal link between inactivation of skeletal cystic fibrosis transmembrane regulator (CFTR, the gene that when mutated causes CF, and CFBD. The objective of this study was to examine the direct actions of CFTR on bone. Expression analyses revealed that CFTR mRNA and protein were expressed in murine osteoblasts, but not in osteoclasts. Functional studies were then performed to investigate the direct actions of CFTR on osteoblasts using a CFTR knockout (Cftr-/- mouse model. In the murine calvarial organ culture assay, Cftr-/- calvariae displayed significantly less bone formation and osteoblast numbers than calvariae harvested from wildtype (Cftr+/+ littermates. CFTR inactivation also reduced alkaline phosphatase expression in cultured murine calvarial osteoblasts. Although CFTR was not expressed in murine osteoclasts, significantly more osteoclasts formed in Cftr-/- compared to Cftr+/+ bone marrow cultures. Indirect regulation of osteoclastogenesis by the osteoblast through RANK/RANKL/OPG signaling was next examined. Although no difference in receptor activator of NF-κB ligand (Rankl mRNA was detected, significantly less osteoprotegerin (Opg was expressed in Cftr-/- compared to Cftr+/+ osteoblasts. Together, the Rankl:Opg ratio was significantly higher in Cftr-/- murine calvarial osteoblasts contributing to a higher osteoclastogenesis potential. The combined findings of reduced osteoblast differentiation and lower Opg expression suggested a possible defect in canonical Wnt signaling. In fact, Wnt3a and PTH-stimulated canonical Wnt

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

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

2015-07-01

Cftr(-/-tm1Unc) 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. We determined bile production, biliary and fecal bile salt- and lipid compositions and fecal bacterial composition of C57BL/6J Cftr(-/-tm1Unc) and control mice. We found no differences between the total biliary bile salt or lipid concentrations of Cftr(-/-) and controls. Compared to controls, Cftr(-/-) mice had a ~30% higher bile production and a low bile hydrophobicity, related to a ~7 fold higher concentration of the choleretic and hydrophilic bile salt ursocholate. These findings coexisted with a significantly smaller quantity of fecal Bacteroides bacteria. Liver pathology in Cftr(-/-tm1Unc) is not related to increased bile hydrophobicity. Cftr(-/-) mice do however display a biliary phenotype characterized by increased bile production and decreased biliary hydrophobicity. Our findings suggest Cftr dependent, alterations in intestinal bacterial biotransformation of bile salts. Copyright © 2014. Published by Elsevier B.V.

The ichthyotoxic alga Chattonella marina induces Na+, K+-ATPase, and CFTR proteins expression in fish gill chloride cells in vivo

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Tang, Janet Y.M.; Wong, Chris K.C.; Au, Doris W.T.

2007-01-01

Our previous studies demonstrated that the ichthyotoxic Chattonella marina stimulated proliferation of branchial chloride cell (CC) and induced osmotic distress akin to hyperactive elimination of ions in fish (Rhabdosargus sarba). To ascertain the in vivo effects of C. marina on key CC ion transporters, the localization and expression of Na + , K + -ATPase (NKA) and cystic fibrosis transmembrane conductance regulator (CFTR) proteins in response to C. marina exposure were investigated, using a quantitative immunocytochemical approach. The polarized distributions of NKA (α subunit) and CFTR proteins in branchial CCs of R. sarba remained unchanged under C. marina exposure. However, significant inductions of these two ion-transporters were detected in CCs of fish after 6 h exposure. By real-time PCR, no significant changes in gill NKA and CFTR mRNA expressions were detected, suggesting a post-transcriptional pathway is likely involved in regulating the ion transporters abundance. This study is the first to demonstrate the in vivo effects of harmful algal toxin on NKA and CFTR protein expressions in gill transepithelial cells. Taken together, an augmentation of branchial CCs together with hyper-stimulation of NKA and CFTR in CCs attribute to the rapid development of osmotic distress in C. marina susceptible fish

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

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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.

Frequency of common CFTR gene mutations in Venezuelan patients with cystic fibrosis

OpenAIRE

Sánchez, Karen; Arcia, Orlando; Matute, Xiorama; Mindiola, Luz; Chaustre, Ismenia; Takiff, Howard

2014-01-01

Mutations in the CFTR gene in Cystic Fibrosis (CF) patients have geographic differences and there is scant data on their prevalence in Venezuelan patients. This study determined the frequency of common CFTR gene mutations in these patients. We amplified and sequenced exons 7, 10, 11, 19, 20 and 21, which contain the most common CFTR mutations, from 105 Venezuelan patients in the National CF Program. Eleven different mutations were identified, four with frequencies greater than 1%: p.Phe508del...

Dendrimer-based selective autophagy-induction rescues ΔF508-CFTR and inhibits Pseudomonas aeruginosa infection in cystic fibrosis.

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Scott Mackenzie Brockman

Full Text Available Cystic Fibrosis (CF is a genetic disorder caused by mutation(s in the CF-transmembrane conductance regulator (Cftr gene. The most common mutation, ΔF508, leads to accumulation of defective-CFTR protein in aggresome-bodies. Additionally, Pseudomonas aeruginosa (Pa, a common CF pathogen, exacerbates obstructive CF lung pathology. In the present study, we aimed to develop and test a novel strategy to improve the bioavailability and potentially achieve targeted drug delivery of cysteamine, a potent autophagy-inducing drug with anti-bacterial properties, by developing a dendrimer (PAMAM-DEN-based cysteamine analogue.We first evaluated the effect of dendrimer-based cysteamine analogue (PAMAM-DENCYS on the intrinsic autophagy response in IB3-1 cells and observed a significant reduction in Ub-RFP and LC3-GFP co-localization (aggresome-bodies by PAMAM-DENCYS treatment as compared to plain dendrimer (PAMAM-DEN control. Next, we observed that PAMAM-DENCYS treatment shows a modest rescue of ΔF508-CFTR as the C-form. Moreover, immunofluorescence microscopy of HEK-293 cells transfected with ΔF508-CFTR-GFP showed that PAMAM-DENCYS is able to rescue the misfolded-ΔF508-CFTR from aggresome-bodies by inducing its trafficking to the plasma membrane. We further verified these results by flow cytometry and observed significant (p<0.05; PAMAM-DEN vs. PAMAM-DENCYS rescue of membrane-ΔF508-CFTR with PAMAM-DENCYS treatment using non-permeabilized IB3-1 cells immunostained for CFTR. Finally, we assessed the autophagy-mediated bacterial clearance potential of PAMAM-DENCYS by treating IB3-1 cells infected with PA01-GFP, and observed a significant (p<0.01; PAMAM-DEN vs. PAMAM-DENCYS decrease in intracellular bacterial counts by immunofluorescence microscopy and flow cytometry. Also, PAMAM-DENCYS treatment significantly inhibits the growth of PA01-GFP bacteria and demonstrates potent mucolytic properties.We demonstrate here the efficacy of dendrimer-based autophagy

Association between F508 deletion in CFTR and chronic pancreatitis risk.

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Zhao, Dong; Xu, Yanzhen; Li, Jiatong; Fu, Shien; Xiao, Feifan; Song, Xiaowei; Xie, Zhibin; Jiang, Min; He, Yan; Liu, Chengwu; Wen, Qiongxian; Yang, Xiaoli

2017-09-01

The cystic fibrosis transmembrane conductance regulator (CFTR) has been reported to influence individual susceptibility to chronic pancreatitis (CP), but the results of previous studies are controversial. We performed a study to demonstrate the relationship between CFTR and CP. We searched PubMed, Scopus, and Embase for studies of patients with CP. Seven studies from 1995 to 2016 were identified, and included 64,832 patients. Pooled prevalence and 95% confidence intervals (CIs) were calculated. F508 deletion in CFTR was significantly positively associated with CP risk in the overall analysis (odds ratio [OR]=3.20, 95% CI: 2.30-4.44, I 2 =31.7%). In subgroup analysis stratified by ethnicity, F508 deletion was significantly associated with CP risk in Indian populations, using a fixed effects model (ORs=5.45, 95% CI: 2.52-11.79, I 2 =0.0%), and in non-Indian populations, using a random effects model (ORs=3.59, 95% CI: 1.73-7.48, I 2 =60.9%). At the same time, we found that Indians with F508 deletion had much higher CP prevalence than non-Indians. Interestingly, F508 deletion was also associated with CP and idiopathic CP risk in subgroup analysis stratified by aeitiology, using the fixed effects model. Based on current evidence, F508 deletion is a risk factor for CP, and Indians with F508 deletion have much higher CP morbidity. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Antibodies to the CFTR modulate the turgor pressure of guard cell protoplasts via slow anion channels.

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Leonhardt, N; Bazin, I; Richaud, P; Marin, E; Vavasseur, A; Forestier, C

2001-04-06

The plasma membrane guard cell slow anion channel is a key element at the basis of water loss control in plants allowing prolonged osmolite efflux necessary for stomatal closure. This channel has been extensively studied by electrophysiological approaches but its molecular identification is still lacking. Recently, we described that this channel was sharing some similarities with the mammalian ATP-binding cassette protein, cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel [Leonhardt, N. et al. (1999) Plant Cell 11, 1141-1151]. Here, using the patch-clamp technique and a bioassay, consisting in the observation of the change in guard cell protoplasts volume, we demonstrated that a functional antibody raised against the mammalian CFTR prevented ABA-induced guard cell protoplasts shrinking and partially inhibited the slow anion current. Moreover, this antibody immunoprecipitated a polypeptide from guard cell protein extracts and immunolabeled stomata in Vicia faba leaf sections. These results indicate that the guard cell slow anion channel is, or is closely controlled by a polypeptide, exhibiting one epitope shared with the mammalian CFTR.

Rescuing mutant CFTR: a multi-task approach to a better outcome in treating cystic fibrosis.

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Amaral, Margarida D; Farinha, Carlos M

2013-01-01

Correcting multiple defects of mutant CFTR with small molecule compounds has been the goal of an increasing number of recent Cystic Fibrosis (CF) drug discovery programmes. However, the mechanism of action (MoA) by which these molecules restore mutant CFTR is still poorly understood, in particular of CFTR correctors, i.e., compounds rescuing to the cells surface the most prevalent mutant in CF patients--F508del-CFTR. However, there is increasing evidence that to fully restore the multiple defects associated with F508del-CFTR, different small molecules with distinct corrective properties may be required. Towards this goal, a better insight into MoA of correctors is needed and several constraints should be addressed. The methodological approaches to achieve this include: 1) testing the combined effect of compounds with that of other (non-pharmacological) rescuing strategies (e.g., revertants or low temperature); 2) assessing effects in multiple cellular models (non-epithelial vs epithelial, non-human vs human, immortalized vs primary cultures, polarized vs non polarized, cells vs tissues); 3) assessing compound effects on isolated CFTR domains (e.g., compound binding by surface plasmon resonance, assessing effects on domain folding and aggregation); and finally 4) assessing compounds specificity in rescuing different CFTR mutants and other mutant proteins. These topics are reviewed and discussed here so as to provide a state-of-the art review on how to combine multiple ways of rescuing mutant CFTR to the ultimate benefit of CF patients.

Les vésicules extracellulaires comme vecteurs de macromolécules bioactives : modèle du transporteur ABCC7 (CFTR) et application à la biothérapie de la mucoviscidose

OpenAIRE

Vituret , Cyrielle

2015-01-01

Cystic fibrosis is a genetic disease in which its prognosis depends on the lung damage. It is caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR), resulting in a dysfunctional CFTR protein normally located at the plasma membrane of epithelial cells. This thesis is a study of a novel therapeutic approach to use extracellular vesicles (EVs), microvesicles and exosomes, as transfer vectors for CFTR mRNA and protein to target cells. The proof of concept for ...

Longevity and plasticity of CFTR provide an argument for noncanonical SNP organization in hominid DNA.

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Aubrey E Hill

Full Text Available Like many other ancient genes, the cystic fibrosis transmembrane conductance regulator (CFTR has survived for hundreds of millions of years. In this report, we consider whether such prodigious longevity of an individual gene--as opposed to an entire genome or species--should be considered surprising in the face of eons of relentless DNA replication errors, mutagenesis, and other causes of sequence polymorphism. The conventions that modern human SNP patterns result either from purifying selection or random (neutral drift were not well supported, since extant models account rather poorly for the known plasticity and function (or the established SNP distributions found in a multitude of genes such as CFTR. Instead, our analysis can be taken as a polemic indicating that SNPs in CFTR and many other mammalian genes may have been generated--and continue to accrue--in a fundamentally more organized manner than would otherwise have been expected. The resulting viewpoint contradicts earlier claims of 'directional' or 'intelligent design-type' SNP formation, and has important implications regarding the pace of DNA adaptation, the genesis of conserved non-coding DNA, and the extent to which eukaryotic SNP formation should be viewed as adaptive.

Hydraulic Conductivity of Residual Soil-Cement Mix

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Govindasamy, P.; Taha, M. R.

2016-07-01

In Malaysia, although there are several researches on engineering properties of residual soils, however study on the hydraulic conductivity properties of metasedimentary residual soils is still lacking. Construction of containment walls like slurry wall techniques can be achieved with hydraulic conductivity of approximately 5 x 10-7cm/sec. The objectives of the study were to determine the physical properties of metasedimentary residual soils and to determine the influence of 1%, 3%, 5% and 10% of cement on hydraulic conductivity parameters. The coefficient of hydraulic conductivity of the soil naturally and soil-cement mixtures were determined by using the falling head test. According to the test, the hydraulic conductivity of the original soil was 4.16 x 10-8 m/s. The value decreases to 3.89 x 10-8 m/s, 2.78 x 10-8 m/s then 6.83 x 10-9 m/s with the addition of 1%, 3% and 5% of cement additives, respectively. During the hydration process, cement hydrates is formed followed by the increase in pH value and Ca(OH)2 which will alter the modification of pores size and distribution. When the quantity of cement increases, the pores size decrease. But, the addition of 10% cement gives an increased hydraulic conductivity value to 2.78 x 10-8 m/s. With 10%, the pore size increase might due to flocculation and agglomeration reaction. The generated hydraulic conductivity values will indirectly become a guide in the preliminary soil cement stabilization to modify the properties of the soil to become more like the properties of a soft rock.1. Introduction

An immortal cell line to study the role of endogenous CFTR in electrolyte absorption.

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Bell, C L; Quinton, P M

1995-01-01

The intact human reabsorptive sweat duct (RD) has been a reliable model for investigations of the functional role of "endogenous" CFTR (cystic fibrosis transmembrane conductance regulator) in normal and abnormal electrolyte absorptive function. But to overcome the limitations imposed by the use of fresh, intact tissue, we transformed cultured RD cells using the chimeric virus Ad5/SV40 1613 ori-. The resultant cell line, RD2(NL), has remained differentiated forming a polarized epithelium that expressed two fundamental components of absorption, a cAMP activated Cl- conductance (GCl) and an amiloride-sensitive Na+ conductance (GNa). In the unstimulated state, there was a low level of transport activity; however, addition of forskolin (10(-5) M) significantly increased the Cl- diffusion potential (Vt) generated by a luminally directed Cl- gradient from -15.3 +/- 0.7 mV to -23.9 +/- 1.1 mV, n = 39; and decreased the transepithelial resistance (Rt) from 814.8 +/- 56.3 omega.cm2 to 750.5 +/- 47.5 omega.cm2, n = 39, (n = number of cultures). cAMP activation, anion selectivity (Cl- > I- > gluconate), and a dependence upon metabolic energy (metabolic poisoning inhibited GCl), all indicate that the GCl expressed in RD2(NL) is in fact CFTR-GCl. The presence of an apical amiloride-sensitive GNa was shown by the amiloride (10(-5) M) inhibition of GNa as indicated by a reduction of Vt and equivalent short circuit current by 78.0 +/- 3.1% and 77.9 +/- 2.6%, respectively, and an increase in Rt by 7.2 +/- 0.8%, n = 36. In conclusion, the RD2(NL) cell line presents the first model system in which CFTR-GCl is expressed in a purely absorptive tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

CFTR-dependent chloride efflux in cystic fibrosis mononuclear cells is increased by ivacaftor therapy.

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Guerra, Lorenzo; D'Oria, Susanna; Favia, Maria; Castellani, Stefano; Santostasi, Teresa; Polizzi, Angela M; Mariggiò, Maria A; Gallo, Crescenzio; Casavola, Valeria; Montemurro, Pasqualina; Leonetti, Giuseppina; Manca, Antonio; Conese, Massimo

2017-07-01

The Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) potentiator ivacaftor (Kalydeco®) improves clinical outcome in G551D cystic fibrosis (CF) patients. Here, we have investigated whether ivacaftor has a clinical impact on non-G551D gating mutations and function of circulating leukocytes as well. Seven patients were treated with ivacaftor and evaluated at baseline, and at 1-3 and 6 months. Besides clinical and systemic inflammatory parameters, circulating mononuclear cells (MNC) were evaluated for CFTR-dependent chloride efflux by spectrofluorimetry, neutrophils for oxidative burst by cytofluorimetry and HVCN1 mRNA expression by real time PCR. Ivacaftor determined a significant decrease in sweat chloride concentrations at all time points during treatment. Body mass index (BMI), FEV 1 , and FVC showed an increasing trend. While C-reactive protein decreased significantly at 2 months, the opposite behavior was noticed for circulating monocytes. CFTR activity in MNC was found to increase significantly at 3 and 6 months. Neutrophil oxidative burst peaked at 2 months and then decreased to baseline. HVCN1 mRNA expression was significantly higher than baseline at 1-3 months and decreased after 6 months of treatment. The chloride efflux in MNC correlated positively with both FEV 1 and FVC. On the other hand, sweat chloride correlated positively with CRP and WBC, and negatively with both respiratory function tests. A cluster analysis confirmed that sweat chloride, FEV 1 , FVC, BMI, and MNC chloride efflux behaved as a single entity over time. In patients with non-G551D mutations, ivacaftor improved both chloride transport in sweat ducts and chloride efflux in MNC, that is, functions directly imputed to CFTR. © 2017 Wiley Periodicals, Inc.

Sweat chloride as a biomarker of CFTR activity: proof of concept and ivacaftor clinical trial data.

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Accurso, Frank J; Van Goor, Fredrick; Zha, Jiuhong; Stone, Anne J; Dong, Qunming; Ordonez, Claudia L; Rowe, Steven M; Clancy, John Paul; Konstan, Michael W; Hoch, Heather E; Heltshe, Sonya L; Ramsey, Bonnie W; Campbell, Preston W; Ashlock, Melissa A

2014-03-01

We examined data from a Phase 2 trial {NCT00457821} of ivacaftor, a CFTR potentiator, in cystic fibrosis (CF) patients with aG551D mutation to evaluate standardized approaches to sweat chloride measurement and to explore the use of sweat chloride and nasal potential difference (NPD) to estimate CFTR activity. Sweat chloride and NPD were secondary endpoints in this placebo-controlled, multicenter trial. Standardization of sweat collection, processing,and analysis was employed for the first time. Sweat chloride and chloride ion transport (NPD) were integrated into a model of CFTR activity. Within-patient sweat chloride determinations showed sufficient precision to detect differences between dose-groups and assess ivacaftor treatment effects. Analysis of changes in sweat chloride and NPD demonstrated that patients treated with ivacaftor achieved CFTR activity equivalent to approximately 35%–40% of normal. Sweat chloride is useful in multicenter trials as a biomarker of CFTR activity and to test the effect of CFTR potentiators.

Cystic fibrosis transmembrane conductance regulator contributes to reacidification of alkalinized lysosomes in RPE cells.

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Liu, Ji; Lu, Wennan; Guha, Sonia; Baltazar, Gabriel C; Coffey, Erin E; Laties, Alan M; Rubenstein, Ronald C; Reenstra, William W; Mitchell, Claire H

2012-07-15

The role of the cystic fibrosis transmembrane conductance regulator (CFTR) in lysosomal acidification has been difficult to determine. We demonstrate here that CFTR contributes more to the reacidification of lysosomes from an elevated pH than to baseline pH maintenance. Lysosomal alkalinization is increasingly recognized as a factor in diseases of accumulation, and we previously showed that cAMP reacidified alkalinized lysosomes in retinal pigmented epithelial (RPE) cells. As the influx of anions to electrically balance proton accumulation may enhance lysosomal acidification, the contribution of the cAMP-activated anion channel CFTR to lysosomal reacidification was probed. The antagonist CFTR(inh)-172 had little effect on baseline levels of lysosomal pH in cultured human RPE cells but substantially reduced the reacidification of compromised lysosomes by cAMP. Likewise, CFTR activators had a bigger impact on cells whose lysosomes had been alkalinized. Knockdown of CFTR with small interfering RNA had a larger effect on alkalinized lysosomes than on baseline levels. Inhibition of CFTR in isolated lysosomes altered pH. While CFTR and Lamp1 were colocalized, treatment with cAMP did not increase targeting of CFTR to the lysosome. The inhibition of CFTR slowed lysosomal degradation of photoreceptor outer segments while activation of CFTR enhanced their clearance from compromised lysosomes. Activation of CFTR acidified RPE lysosomes from the ABCA4(-/-) mouse model of recessive Stargardt's disease, whose lysosomes are considerably alkalinized. In summary, CFTR contributes more to reducing lysosomal pH from alkalinized levels than to maintaining baseline pH. Treatment to activate CFTR may thus be of benefit in disorders of accumulation associated with lysosomal alkalinization.

Emerging role of cystic fibrosis transmembrane conductance regulator- an epithelial chloride channel in gastrointestinal cancers

Institute of Scientific and Technical Information of China (English)

Yuning Hou; Xiaoqing Guan; Zhe Yang; Chunying Li

2016-01-01

Cystic fibrosis transmembrane conductance regulator(CFTR), a glycoprotein with 1480 amino acids, has been well established as a chloride channel mainly expressed in the epithelial cells of various tissues and organs such as lungs, sweat glands, gastrointestinal system, and reproductive organs. Although defective CFTR leads to cystic fibrosis, a common genetic disorder in the Caucasian population, there is accumulating evidence that suggests a novel role of CFTR in various cancers, especially in gastroenterological cancers, such as pancreatic cancer and colon cancer. In this review, we summarize the emerging findings that link CFTR with various cancers, with focus on the association between CFTR defects and gastrointestinal cancers as well as the underlying mechanisms. Further study of CFTR in cancer biology may help pave a new way for the diagnosis and treatment of gastrointestinal cancers.

Cftr Modulates Wnt/β-Catenin Signaling and Stem Cell Proliferation in Murine Intestine

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Ashlee M. Strubberg

2018-01-01

Conclusions: CF intestine shows increased ISC proliferation and Wnt/β-catenin signaling. Loss of Cftr increases pHi in ISCs, which stabilizes the plasma membrane association of the Wnt transducer Dvl, likely facilitating Wnt/β-catenin signaling. Absence of Cftr-dependent suppression of ISC proliferation in the CF intestine may contribute to increased risk for intestinal tumors.

Cysteamine re-establishes the clearance of Pseudomonas aeruginosa by macrophages bearing the cystic fibrosis-relevant F508del-CFTR mutation.

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Ferrari, Eleonora; Monzani, Romina; Villella, Valeria R; Esposito, Speranza; Saluzzo, Francesca; Rossin, Federica; D'Eletto, Manuela; Tosco, Antonella; De Gregorio, Fabiola; Izzo, Valentina; Maiuri, Maria C; Kroemer, Guido; Raia, Valeria; Maiuri, Luigi

2017-01-12

Cystic fibrosis (CF), the most common lethal monogenic disease in Caucasians, is characterized by recurrent bacterial infections and colonization, mainly by Pseudomonas aeruginosa, resulting in unresolved airway inflammation. CF is caused by mutations in the gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein, which functions as a chloride channel in epithelial cells, macrophages, and other cell types. Impaired bacterial handling by macrophages is a feature of CF airways, although it is still debated how defective CFTR impairs bacterial killing. Recent evidence indicates that a defective autophagy in CF macrophages leads to alterations of bacterial clearance upon infection. Here we use bone marrow-derived macrophages from transgenic mice to provide the genetic proof that defective CFTR compromises both uptake and clearance of internalized Pseudomonas aeruginosa. We demonstrate that the proteostasis regulator cysteamine, which rescues the function of the most common F508del-CFTR mutant and hence reduces lung inflammation in CF patients, can also repair the defects of CF macrophages, thus restoring both bacterial internalization and clearance through a process that involves upregulation of the pro-autophagic protein Beclin 1 and re-establishment of the autophagic pathway. Altogether these results indicate that cysteamine restores the function of several distinct cell types, including that of macrophages, which might contribute to its beneficial effects on CF.

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

International Nuclear Information System (INIS)

Taulan, M.; Lopez, E.; Guittard, C.; Rene, C.; Baux, D.; Altieri, J.P.; DesGeorges, M.; Claustres, M.; Romey, M.C.

2007-01-01

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

Mercury toxicity in the shark (Squalus acanthias) rectal gland: apical CFTR chloride channels are inhibited by mercuric chloride.

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Ratner, Martha A; Decker, Sarah E; Aller, Stephen G; Weber, Gerhard; Forrest, John N

2006-03-01

In the shark rectal gland, basolateral membrane proteins have been suggested as targets for mercury. To examine the membrane polarity of mercury toxicity, we performed experiments in three preparations: isolated perfused rectal glands, primary monolayer cultures of rectal gland epithelial cells, and Xenopus oocytes expressing the shark cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. In perfused rectal glands we observed: (1) a dose-dependent inhibition by mercury of forskolin/3-isobutyl-1-methylxanthine (IBMX)-stimulated chloride secretion; (2) inhibition was maximal when mercury was added before stimulation with forskolin/IBMX; (3) dithiothrietol (DTT) and glutathione (GSH) completely prevented inhibition of chloride secretion. Short-circuit current (Isc) measurements in monolayers of rectal gland epithelial cells were performed to examine the membrane polarity of this effect. Mercuric chloride inhibited Isc more potently when applied to the solution bathing the apical vs. the basolateral membrane (23 +/- 5% and 68 +/- 5% inhibition at 1 and 10 microM HgCl2 in the apical solution vs. 2 +/- 0.9% and 14 +/- 5% in the basolateral solution). This inhibition was prevented by pre-treatment with apical DTT or GSH; however, only the permeant reducing agent DTT reversed mercury inhibition when added after exposure. When the shark rectal gland CFTR channel was expressed in Xenopus oocytes and chloride conductance was measured by two-electrode voltage clamping, we found that 1 microM HgCl2 inhibited forskolin/IBMX conductance by 69.2 +/- 2.0%. We conclude that in the shark rectal gland, mercury inhibits chloride secretion by interacting with the apical membrane and that CFTR is the likely site of this action. Copyright 2006 Wiley-Liss, Inc.

Lumacaftor/ivacaftor, a novel agent for the treatment of cystic fibrosis patients who are homozygous for the F580del CFTR mutation.

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Bulloch, Marilyn N; Hanna, Cameron; Giovane, Richard

2017-10-01

Cystic Fibrosis (CF) is an autosomal recessive disease affecting up to 90,000 people worldwide. Approximately 73% of patients are homozygous for the F508del cystic fibrosis transmembrane conductance regulator [CFTR] mutation. Traditionally treatment has only included supportive care. Therefore, there is a need for safe and effective novel therapies targeting the underlying molecular defects seen with CF. Areas covered: In 2016, the Food and Drug Administration and the European Commission approved LUM/IVA (Orkambi), a CFTR modulator that includes both a CFTR corrector and potentiator, for CF patients homozygous for the F508del CFTR mutation. This article reviews the pharmacologic features, clinical efficacy, and safety of LUM/IVA and summarize the available pre-clinical and clinical data of LUM/IVA use. Expert commentary: LUM/IVA showed modest, but significant improvements from baseline in percent predicted FEV 1 (ppFEV 1 ) as well as a reduction in pulmonary exacerbations by 35% It was shown to be safe for short- and long-term use. Currently, LUM/IVA is the only oral agent in its class available and represents a milestone the development of therapies for the management of CF. Nonetheless, pharmacoeconomic data are necessary to justify its high cost before is use becomes standard of care.

Structure and function of the cystic fibrosis transmembrane conductance regulator

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M.M. Morales

1999-08-01

Full Text Available Cystic fibrosis (CF is a lethal autosomal recessive genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR. Mutations in the CFTR gene may result in a defective processing of its protein and alter the function and regulation of this channel. Mutations are associated with different symptoms, including pancreatic insufficiency, bile duct obstruction, infertility in males, high sweat Cl-, intestinal obstruction, nasal polyp formation, chronic sinusitis, mucus dehydration, and chronic Pseudomonas aeruginosa and Staphylococcus aureus lung infection, responsible for 90% of the mortality of CF patients. The gene responsible for the cellular defect in CF was cloned in 1989 and its protein product CFTR is activated by an increase of intracellular cAMP. The CFTR contains two membrane domains, each with six transmembrane domain segments, two nucleotide-binding domains (NBDs, and a cytoplasmic domain. In this review we discuss the studies that have correlated the role of each CFTR domain in the protein function as a chloride channel and as a regulator of the outwardly rectifying Cl- channels (ORCCs.

Cystic fibrosis transmembrane conductance regulator intracellular processing, trafficking, and opportunities for mutation-specific treatment.

LENUS (Irish Health Repository)

Rogan, Mark P

2012-02-01

Recent advances in basic science have greatly expanded our understanding of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR), the chloride and bicarbonate channel that is encoded by the gene, which is mutated in patients with CF. We review the structure, function, biosynthetic processing, and intracellular trafficking of CFTR and discuss the five classes of mutations and their impact on the CF phenotype. The therapeutic discussion is focused on the significant progress toward CFTR mutation-specific therapies. We review the results of encouraging clinical trials examining orally administered therapeutics, including agents that promote read-through of class I mutations (premature termination codons); correctors, which overcome the CFTR misfolding that characterizes the common class II mutation F508del; and potentiators, which enhance the function of class III or IV mutated CFTR at the plasma membrane. Long-term outcomes from successful mutation-specific treatments could finally answer the question that has been lingering since and even before the CFTR gene discovery: Will therapies that specifically restore CFTR-mediated chloride secretion slow or arrest the deleterious cascade of events leading to chronic infection, bronchiectasis, and end-stage lung disease?

Stimulation of Intestinal Cl- Secretion Through CFTR by Caffeine Intake in Salt-Sensitive Hypertensive Rats

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Xiao Wei

2018-03-01

Full Text Available Background/Aims: High salt consumption is a major risk factor for hypertension, and sodium homeostasis is regulated by both intestinal sodium absorption and urinary sodium excretion. Chronic caffeine intake has been reported to attenuate salt-sensitive hypertension by promoting urinary sodium excretion; however, its exact role in intestinal sodium absorption remains unknown. Here, we investigated whether and how chronic caffeine consumption antagonizes salt-sensitive hypertension by inhibiting intestinal sodium absorption. Methods: Dahl salt-sensitive rats were fed 8% NaCl chow and 0.1% caffeine in their drinking water for 15 days. The blood pressure and fecal sodium content were measured. The effect of caffeine on the movement of Cl- in enterocyte cells was determined with the Ussing chamber assay. Results: Rats that were treated with caffeine displayed significantly lower mean blood pressure and higher fecal sodium content than the controls. Consistent with these findings, caffeine intake decreased fluid absorption by the intestine in the fluid perfusion experiment. Further, the results from the Ussing chamber assay indicated that caffeine promoted Cl- secretion through enterocyte apical cystic fibrosis transmembrane conductance regulator (CFTR, and thus inhibited sodium absorption. Moreover, depletion of cAMP or inhibition of CFTR completely abolished the effect of caffeine on Cl- secretion. Conclusion: The results indicate that chronic caffeine consumption reduces sodium absorption by promoting CFTR-mediated Cl- secretion in the intestine, which contributes to the anti-hypertensive effect of caffeine in salt-sensitive rats.

Genomic sequencing in cystic fibrosis newborn screening: what works best, two-tier predefined CFTR mutation panels or second-tier CFTR panel followed by third-tier sequencing?

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Currier, Robert J; Sciortino, Stan; Liu, Ruiling; Bishop, Tracey; Alikhani Koupaei, Rasoul; Feuchtbaum, Lisa

2017-10-01

PurposeThe purpose of this study was to model the performance of several known two-tier, predefined mutation panels and three-tier algorithms for cystic fibrosis (CF) screening utilizing the ethnically diverse California population.MethodsThe cystic fibrosis transmembrane conductance regulator (CFTR) mutations identified among the 317 CF cases in California screened between 12 August 2008 and 18 December 2012 were used to compare the expected CF detection rates for several two- and three-tier screening approaches, including the current California approach, which consists of a population-specific 40-mutation panel followed by third-tier sequencing when indicated.ResultsThe data show that the strategy of using third-tier sequencing improves CF detection following an initial elevated immunoreactive trypsinogen and detection of only one mutation on a second-tier panel.ConclusionIn a diverse population, the use of a second-tier panel followed by third-tier CFTR gene sequencing provides a better detection rate for CF, compared with the use of a second-tier approach alone, and is an effective way to minimize the referrals of CF carriers for sweat testing. Restricting screening to a second-tier testing to predefined mutation panels, even broad ones, results in some missed CF cases and demonstrates the limited utility of this approach in states that have diverse multiethnic populations.

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

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

2002-01-01

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...

Analysis of cystic fibrosis gener product (CFTR) function in patients with pancreas divisum and recurrent acute pancreatitis.

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Gelrud, Andres; Sheth, Sunil; Banerjee, Subhas; Weed, Deborah; Shea, Julie; Chuttani, Ram; Howell, Douglas A; Telford, Jennifer J; Carr-Locke, David L; Regan, Meredith M; Ellis, Lynda; Durie, Peter R; Freedman, Steven D

2004-08-01

The mechanism by which pancreas divisum may lead to recurrent episodes of acute pancreatitis in a subset of individuals is unknown. Abnormalities of the cystic fibrosis gene product (CFTR) have been implicated in the genesis of idiopathic chronic pancreatitis. The aim of this study was to determine if CFTR function is abnormal in patients with pancreas divisum and recurrent acute pancreatitis (PD/RAP). A total of 69 healthy control subjects, 12 patients with PD/RAP, 16 obligate heterozygotes with a single CFTR mutation, and 95 patients with cystic fibrosis were enrolled. CFTR function was analyzed by nasal transepithelial potential difference testing in vivo. The outcomes of the PD/RAP patients following endoscopic and surgical treatments were concomitantly analyzed. Direct measurement of CFTR function in nasal epithelium in response to isoproterenol demonstrated that the values for PD/RAP were intermediate between those observed for healthy controls and cystic fibrosis patients. The median value was 13 mV for PD/RAP subjects, which was statistically different from healthy controls (22 mV, p= 0.001) and cystic fibrosis pancreatic sufficient (-1 mV, p < 0.0001) and pancreatic insufficient (-3 mV, p < 0.0001) patients. These results suggest a link between CFTR dysfunction and recurrent acute pancreatitis in patients with pancreas divisum and may explain why a subset of patients with pancreas divisum develops recurrent acute pancreatitis. Copyright 2004 American College of Gastroenterology

CFTR mutations spectrum and the efficiency of molecular diagnostics in Polish cystic fibrosis patients.

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Ewa Ziętkiewicz

Full Text Available Cystic fibrosis (CF is caused by mutations in the cystic fibrosis transmembrane regulator gene (CFTR. In light of the strong allelic heterogeneity and regional specificity of the mutation spectrum, the strategy of molecular diagnostics and counseling in CF requires genetic tests to reflect the frequency profile characteristic for a given population. The goal of the study was to provide an updated comprehensive estimation of the distribution of CFTR mutations in Polish CF patients and to assess the effectiveness of INNOLiPA_CFTR tests in Polish population. The analyzed cohort consisted of 738 patients with the clinically confirmed CF diagnosis, prescreened for molecular defects using INNOLiPA_CFTR panels from Innogenetics. A combined efficiency of INNOLiPA CFTR_19 and CFTR_17_TnUpdate tests was 75.5%; both mutations were detected in 68.2%, and one mutation in 14.8% of the affected individuals. The group composed of all the patients with only one or with no mutation detected (109 and 126 individuals, respectively was analyzed further using a mutation screening approach, i.e. SSCP/HD (single strand conformational polymorphism/heteroduplex analysis of PCR products followed by sequencing of the coding sequence. As a result, 53 more mutations were found in 97 patients. The overall efficiency of the CF allele detection was 82.5% (7.0% increase compared to INNOLiPA tests alone. The distribution of the most frequent mutations in Poland was assessed. Most of the mutations repetitively found in Polish patients had been previously described in other European populations. The most frequent mutated allele, F508del, represented 54.5% of Polish CF chromosomes. Another eight mutations had frequencies over 1%, 24 had frequencies between 1 and 0.1%; c.2052-2053insA and c.3468+2_3468+3insT were the most frequent non-INNOLiPA mutations. Mutation distribution described herein is also relevant to the Polish diaspora. Our study also demonstrates that the reported

Resveratrol enhances airway surface liquid depth in sinonasal epithelium by increasing cystic fibrosis transmembrane conductance regulator open probability.

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Shaoyan Zhang

Full Text Available Chronic rhinosinusitis engenders enormous morbidity in the general population, and is often refractory to medical intervention. Compounds that augment mucociliary clearance in airway epithelia represent a novel treatment strategy for diseases of mucus stasis. A dominant fluid and electrolyte secretory pathway in the nasal airways is governed by the cystic fibrosis transmembrane conductance regulator (CFTR. The objectives of the present study were to test resveratrol, a strong potentiator of CFTR channel open probability, in preparation for a clinical trial of mucociliary activators in human sinus disease.Primary sinonasal epithelial cells, immortalized bronchoepithelial cells (wild type and F508del CFTR, and HEK293 cells expressing exogenous human CFTR were investigated by Ussing chamber as well as patch clamp technique under non-phosphorylating conditions. Effects on airway surface liquid depth were measured using confocal laser scanning microscopy. Impact on CFTR gene expression was measured by quantitative reverse transcriptase polymerase chain reaction.Resveratrol is a robust CFTR channel potentiator in numerous mammalian species. The compound also activated temperature corrected F508del CFTR and enhanced CFTR-dependent chloride secretion in human sinus epithelium ex vivo to an extent comparable to the recently approved CFTR potentiator, ivacaftor. Using inside out patches from apical membranes of murine cells, resveratrol stimulated an ~8 picosiemens chloride channel consistent with CFTR. This observation was confirmed in HEK293 cells expressing exogenous CFTR. Treatment of sinonasal epithelium resulted in a significant increase in airway surface liquid depth (in µm: 8.08+/-1.68 vs. 6.11+/-0.47,control,p<0.05. There was no increase CFTR mRNA.Resveratrol is a potent chloride secretagogue from the mucosal surface of sinonasal epithelium, and hydrates airway surface liquid by increasing CFTR channel open probability. The foundation for a

Role of Interaction and Nucleoside Diphosphate Kinase B in Regulation of the Cystic Fibrosis Transmembrane Conductance Regulator Function by cAMP-Dependent Protein Kinase A.

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Lee A Borthwick

Full Text Available Cystic fibrosis results from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR, a cAMP-dependent protein kinase A (PKA and ATP-regulated chloride channel. Here, we demonstrate that nucleoside diphosphate kinase B (NDPK-B, NM23-H2 forms a functional complex with CFTR. In airway epithelia forskolin/IBMX significantly increases NDPK-B co-localisation with CFTR whereas PKA inhibitors attenuate complex formation. Furthermore, an NDPK-B derived peptide (but not its NDPK-A equivalent disrupts the NDPK-B/CFTR complex in vitro (19-mers comprising amino acids 36-54 from NDPK-B or NDPK-A. Overlay (Far-Western and Surface Plasmon Resonance (SPR analysis both demonstrate that NDPK-B binds CFTR within its first nucleotide binding domain (NBD1, CFTR amino acids 351-727. Analysis of chloride currents reflective of CFTR or outwardly rectifying chloride channels (ORCC, DIDS-sensitive showed that the 19-mer NDPK-B peptide (but not its NDPK-A equivalent reduced both chloride conductances. Additionally, the NDPK-B (but not NDPK-A peptide also attenuated acetylcholine-induced intestinal short circuit currents. In silico analysis of the NBD1/NDPK-B complex reveals an extended interaction surface between the two proteins. This binding zone is also target of the 19-mer NDPK-B peptide, thus confirming its capability to disrupt NDPK-B/CFTR complex. We propose that NDPK-B forms part of the complex that controls chloride currents in epithelia.

Targeting autophagy as a novel strategy for facilitating the therapeutic action of potentiators on ΔF508 cystic fibrosis transmembrane conductance regulator

NARCIS (Netherlands)

A. Luciani (Alessandro); V.R. Villella (Valeria Rachela); S. Esposito (Susanna); M. Gavina (Manuela); I. Russo (Ilaria); M. Silano (Marco); S. Guido (Stefano); M. Pettoello-Mantovani (Massimo); R. Carnuccio (Rosa); B.J. Scholte (Bob); A. de Matteis (Antonella); M.C. Maiuri (Maria Chiara); V. Raia (Valeria); A. Luini (Alberto); H.K. Kroemer (Heyo); L. Maiuri (Luigi)

2012-01-01

textabstractChannel activators (potentiators) of cystic fibrosis (CF) transmembrane conductance regulator (CFTR), can be used for the treatment of the small subset of CF patients that carry plasma membrane-resident CFTR mutants. However, approximately 90% of CF patients carry the misfolded

Impact of the [delta]F508 Mutation in First Nucleotide-binding Domain of Human Cystic Fibrosis Transmembrane Conductance Regulator on Domain Folding and Structure

Energy Technology Data Exchange (ETDEWEB)

Lewis, Hal A.; Zhao, Xun; Wang, Chi; Sauder, J. Michael; Rooney, Isabelle; Noland, Brian W.; Lorimer, Don; Kearins, Margaret C.; Conners, Kris; Condon, Brad; Maloney, Peter C.; Guggino, William B.; Hunt, John F.; Emtage, Spencer (SG); (Columbia); (JHU)

2010-07-19

Cystic fibrosis is caused by defects in the cystic fibrosis transmembrane conductance regulator (CFTR), commonly the deletion of residue Phe-508 (DeltaF508) in the first nucleotide-binding domain (NBD1), which results in a severe reduction in the population of functional channels at the epithelial cell surface. Previous studies employing incomplete NBD1 domains have attributed this to aberrant folding of DeltaF508 NBD1. We report structural and biophysical studies on complete human NBD1 domains, which fail to demonstrate significant changes of in vitro stability or folding kinetics in the presence or absence of the DeltaF508 mutation. Crystal structures show minimal changes in protein conformation but substantial changes in local surface topography at the site of the mutation, which is located in the region of NBD1 believed to interact with the first membrane spanning domain of CFTR. These results raise the possibility that the primary effect of DeltaF508 is a disruption of proper interdomain interactions at this site in CFTR rather than interference with the folding of NBD1. Interestingly, increases in the stability of NBD1 constructs are observed upon introduction of second-site mutations that suppress the trafficking defect caused by the DeltaF508 mutation, suggesting that these suppressors might function indirectly by improving the folding efficiency of NBD1 in the context of the full-length protein. The human NBD1 structures also solidify the understanding of CFTR regulation by showing that its two protein segments that can be phosphorylated both adopt multiple conformations that modulate access to the ATPase active site and functional interdomain interfaces.

Diminished self-chaperoning activity of the DeltaF508 mutant of CFTR results in protein misfolding.

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Adrian W R Serohijos

2008-02-01

Full Text Available The absence of a functional ATP Binding Cassette (ABC protein called the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR from apical membranes of epithelial cells is responsible for cystic fibrosis (CF. Over 90% of CF patients carry at least one mutant allele with deletion of phenylalanine at position 508 located in the N-terminal nucleotide binding domain (NBD1. Biochemical and cell biological studies show that the DeltaF508 mutant exhibits inefficient biosynthetic maturation and susceptibility to degradation probably due to misfolding of NBD1 and the resultant misassembly of other domains. However, little is known about the direct effect of the Phe508 deletion on the NBD1 folding, which is essential for rational design strategies of cystic fibrosis treatment. Here we show that the deletion of Phe508 alters the folding dynamics and kinetics of NBD1, thus possibly affecting the assembly of the complete CFTR. Using molecular dynamics simulations, we find that meta-stable intermediate states appearing on wild type and mutant folding pathways are populated differently and that their kinetic accessibilities are distinct. The structural basis of the increased misfolding propensity of the DeltaF508 NBD1 mutant is the perturbation of interactions in residue pairs Q493/P574 and F575/F578 found in loop S7-H6. As a proof-of-principle that the S7-H6 loop conformation can modulate the folding kinetics of NBD1, we virtually design rescue mutations in the identified critical interactions to force the S7-H6 loop into the wild type conformation. Two redesigned NBD1-DeltaF508 variants exhibited significantly higher folding probabilities than the original NBD1-DeltaF508, thereby partially rescuing folding ability of the NBD1-DeltaF508 mutant. We propose that these observed defects in folding kinetics of mutant NBD1 may also be modulated by structures separate from the 508 site. The identified structural determinants of increased misfolding propensity of

Trafficking and function of the cystic fibrosis transmembrane conductance regulator: a complex network of posttranslational modifications

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McClure, Michelle L.; Barnes, Stephen; Brodsky, Jeffrey L.

2016-01-01

Posttranslational modifications add diversity to protein function. Throughout its life cycle, the cystic fibrosis transmembrane conductance regulator (CFTR) undergoes numerous covalent posttranslational modifications (PTMs), including glycosylation, ubiquitination, sumoylation, phosphorylation, and palmitoylation. These modifications regulate key steps during protein biogenesis, such as protein folding, trafficking, stability, function, and association with protein partners and therefore may serve as targets for therapeutic manipulation. More generally, an improved understanding of molecular mechanisms that underlie CFTR PTMs may suggest novel treatment strategies for CF and perhaps other protein conformational diseases. This review provides a comprehensive summary of co- and posttranslational CFTR modifications and their significance with regard to protein biogenesis. PMID:27474090

Function and expression of cystic fibrosis transmembrane conductance regulator after small intestinal transplantation in mice.

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Penghong Song

Full Text Available The secretion function of intestinal graft is one of the most important factors for successful intestinal transplantation. Cystic fibrosis transmembrane conductance regulator (CFTR mediates HCO3(- and Cl(- secretions in intestinal epithelial cells. In this study, we made investigation on the expression and function of CFTR in an experimental model of murine small intestinal transplantation. Heterotopic intestinal transplantations were performed in syngeneic mice. The mRNA and protein expressions of CFTR were analyzed by real time PCR and western blot. Murine intestinal mucosal HCO3(- and Cl(- secretions were examined in vitro in Ussing chambers by the pH stat and short circuit current (I(sc techniques. The results showed that forskolin, an activator of CFTR, stimulated jejunal mucosal epithelial HCO3(- and Cl(- secretions in mice, but forskolin-stimulated HCO3(- and Cl(- secretions in donor and recipient jejunal mucosae of mice after heterotopic jejunal transplantation were markedly decreased, compared with controls (P<0.001. The mRNA and protein expression levels of CFTR in donor and recipient jejunal mucosae of mice were also markedly lower than those in controls (P<0.001, and the mRNA and protein expression levels of tumor necrosis factor α (TNFα were markedly increased in donor jejunal mucosae of mice (P<0.001, compared with controls. Further experiments showed that TNFα down-regulated the expression of CFTR mRNA in murine jejunal mucosa. In conclusion, after intestinal transplantation, the function of CFTR was impaired, and its mRNA and protein expressions were down-regulated, which may be induced by TNFα.

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

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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.

Purinergic regulation of CFTR and Ca²⁺ -activated C^l- channels and K⁺ channels in human pancreatic duct epithelium

DEFF Research Database (Denmark)

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

2013-01-01

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...

Haplotype block structure study of the CFTR gene. Most variants are associated with the M470 allele in several European populations.

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Pompei, Fiorenza; Ciminelli, Bianca Maria; Bombieri, Cristina; Ciccacci, Cinzia; Koudova, Monika; Giorgi, Silvia; Belpinati, Francesca; Begnini, Angela; Cerny, Milos; Des Georges, Marie; Claustres, Mireille; Ferec, Claude; Macek, Milan; Modiano, Guido; Pignatti, Pier Franco

2006-01-01

An average of about 1700 CFTR (cystic fibrosis transmembrane conductance regulator) alleles from normal individuals from different European populations were extensively screened for DNA sequence variation. A total of 80 variants were observed: 61 coding SNSs (results already published), 13 noncoding SNSs, three STRs, two short deletions, and one nucleotide insertion. Eight DNA variants were classified as non-CF causing due to their high frequency of occurrence. Through this survey the CFTR has become the most exhaustively studied gene for its coding sequence variability and, though to a lesser extent, for its noncoding sequence variability as well. Interestingly, most variation was associated with the M470 allele, while the V470 allele showed an 'extended haplotype homozygosity' (EHH). These findings make us suggest a role for selection acting either on the M470V itself or through an hitchhiking mechanism involving a second site. The possible ancient origin of the V allele in an 'out of Africa' time frame is discussed.

Role of ATP binding and hydrolysis in the gating of the cystic fibrosis transmembrane conductance regulator

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Taras Gout

2012-01-01

Full Text Available The CFTR gene is unique within the ATP-binding cassette (ABC protein family, predominantly of transporters, by coding a chloride channel. The gating mechanism of ABC proteins has been characterized by the ATP Switch model in terms cycles of dimer formation and dissociation linked to ATP binding and hydrolysis, respectively. It would be of interest to assess the extent that Cystic Fibrosis Transmembrane Conductance Regulator (CFTR, a functional channel, fits the ATP Switch model for ABC transporters. Additional transporter mechanisms, namely those of Pgp and HlyB, are discussed for perspective. Literature search of databases selected key references in comparing and contrasting the gating mechanism. CFTR is a functional chloride channel facilitating transmembrane anion flow down electrochemical gradients. A dysfunctional CFTR protein results in cystic fibrosis, a fatal pleiotropic disease currently managed symptomatically. Understanding the gating mechanism will help target drug development aimed at alleviating and curing the disease.

Orphan missense mutations in the cystic fibrosis transmembrane conductance regulator: A three-step biological approach to establishing a correlation between genotype and phenotype.

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Fresquet, Fleur; Clement, Romain; Norez, Caroline; Sterlin, Adélaïde; Melin, Patricia; Becq, Frédéric; Kitzis, Alain; Thoreau, Vincent; Bilan, Frédéric

2011-09-01

More than 1860 mutations have been found within the human cystic fibrosis transmembrane conductance regulator (CFTR) gene sequence. These mutations can be classified according to their degree of severity in CF disease. Although the most common mutations are well characterized, few data are available for rare mutations. Thus, genetic counseling is particularly difficult when fetuses or patients with CF present these orphan variations. We describe a three-step in vitro assay that can evaluate rare missense CFTR mutation consequences to establish a correlation between genotype and phenotype. By using a green fluorescent protein-tagged CFTR construct, we expressed mutated proteins in COS-7 cells. CFTR trafficking was visualized by confocal microscopy, and the cellular localization of CFTR was determined using intracellular markers. We studied the CFTR maturation process using Western blot analysis and evaluated CFTR channel activity by automated iodide efflux assays. Of six rare mutations that we studied, five have been isolated in our laboratory. The cellular and functional impact that we observed in each case was compared with the clinical data concerning the patients in whom we encountered these mutations. In conclusion, we propose that performing this type of analysis for orphan CFTR missense mutations can improve CF genetic counseling. Copyright © 2011 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Novel CFTR missense mutations in Brazilian patients with congenital absence of vas deferens: counseling issues Mutações novas no gene CFTR de pacientes brasileiros portadores de agenesia dos vasos deferentes: dificuldades no aconselhamento

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Patricia de Campos Pieri

2007-01-01

Full Text Available PURPOSE: Screening for mutations in the entire Cystic Fibrosis gene (CFTR of Brazilian infertile men with congenital absence of vas deferens, in order to prevent transmission of CFTR mutations to offspring with the use of assisted reproductive technologies. METHOD: Specific polymerase chain reaction (PCR primers were designed to each of the 27 exons and splicing sites of interest followed by single strand conformational polymorphism and Heteroduplex Analysis (SSCP-HA in precast 12.5% polyacrylamide gels at 7ºC and 20ºC. Fragments with abnormal SSCP migration pattern were sequenced. RESULTS: Two novel missense mutations (S753R and G149W were found in three patients (two brothers together with the IVS8-5T allele in hetrozygosis. CONCLUSION: The available screenings for CF mutations do not include the atypical mutations associated to absence of vas deferens and thus, when these tests fail to find mutations, there is still a genetic risk of affected children with the help of assisted reproduction. We recommend the screening of the whole CFTR gene for these infertile couples, as part of the work-up before assisted reproduction.OBJETIVO: Pesquisar mutações em toda a extensão do gene que causa a Fibrose Cística (CFTR de homens brasileiros inférteis por agenesia congênita dos vasos deferentes, com a finalidade de prevenir a transmissão de mutações em CFTR à prole com o uso das tecnologias de reprodução assistida. MÉTODOS: Foram desenhados oligonucleotídeos específicos para realização de reação de polimerização em cadeia (PCR para cada um dos 27 exons e sítios de processamento de interesse no gene CFTR. O PCR foi seguido pela técnica de SSCP-HA (polimorfismos de conformação no DNA de fita simples e na formação de heteroduplexes em géis pré-fabricados de poliacrilamida a 12,5% em duas temperaturas, 7ºC e 20ºC. Os fragmentos com padrão alterado na migração do SSCP foram submetidos a seqüenciamento automatizado

Cystic fibrosis transmembrane conductance regulator is correlated closely with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters.

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Jiang, L-Y; Shan, J-J; Tong, X-M; Zhu, H-Y; Yang, L-Y; Zheng, Q; Luo, Y; Shi, Q-X; Zhang, S-Y

2014-10-01

Cystic fibrosis transmembrane conductance regulator (CFTR) has been demonstrated to be expressed in mature spermatozoa and correlated with sperm quality. Sperm CFTR expression in fertile men is higher than that in infertile men suffering from teratospermia, asthenoteratospermia, asthenospermia and oligospermia, but it is unknown whether CFTR is correlated with sperm parameters when sperm parameters are normal. In this study, 282 healthy and fertile men with normal semen parameters were classified into three age groups, group (I): age group of 20-29 years (98 cases, 27.1 ± 6.2), group (II): age group of 30-39 years (142 cases, 33.7 ± 2.6) and group (III): age group of more than or equal to 40 years (42 cases, 44.1 ± 4.6). Sperm concentration, total count and progressive motility were analysed by computer-assisted sperm analysis. Sperm morphology was analysed by modified Papanicolaou staining. Sperm CFTR expression was conducted by indirect immunofluorescence staining. There was a significant positive correlation (P sperm progressive motility (r = 0.221) and normal morphology (r = 0.202), but there were no correlations between sperm CFTR expression and semen volume, sperm concentration, sperm total count as well as male age (P > 0.05). Our findings show that CFTR expression is associated with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters, but not associated with the number of spermatozoa and male age. © 2013 Blackwell Verlag GmbH.

Microparticle-mediated transfer of the viral receptors CAR and CD46, and the CFTR channel in a CHO cell model confers new functions to target cells.

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Gaëlle Gonzalez

Full Text Available Cell microparticles (MPs released in the extracellular milieu can embark plasma membrane and intracellular components which are specific of their cellular origin, and transfer them to target cells. The MP-mediated, cell-to-cell transfer of three human membrane glycoproteins of different degrees of complexity was investigated in the present study, using a CHO cell model system. We first tested the delivery of CAR and CD46, two monospanins which act as adenovirus receptors, to target CHO cells. CHO cells lack CAR and CD46, high affinity receptors for human adenovirus serotype 5 (HAdV5, and serotype 35 (HAdV35, respectively. We found that MPs derived from CHO cells (MP-donor cells constitutively expressing CAR (MP-CAR or CD46 (MP-CD46 were able to transfer CAR and CD46 to target CHO cells, and conferred selective permissiveness to HAdV5 and HAdV35. In addition, target CHO cells incubated with MP-CD46 acquired the CD46-associated function in complement regulation. We also explored the MP-mediated delivery of a dodecaspanin membrane glycoprotein, the CFTR to target CHO cells. CFTR functions as a chloride channel in human cells and is implicated in the genetic disease cystic fibrosis. Target CHO cells incubated with MPs produced by CHO cells constitutively expressing GFP-tagged CFTR (MP-GFP-CFTR were found to gain a new cellular function, the chloride channel activity associated to CFTR. Time-course analysis of the appearance of GFP-CFTR in target cells suggested that MPs could achieve the delivery of CFTR to target cells via two mechanisms: the transfer of mature, membrane-inserted CFTR glycoprotein, and the transfer of CFTR-encoding mRNA. These results confirmed that cell-derived MPs represent a new class of promising therapeutic vehicles for the delivery of bioactive macromolecules, proteins or mRNAs, the latter exerting the desired therapeutic effect in target cells via de novo synthesis of their encoded proteins.

EG-VEGF, BV8, and their receptor expression in human bronchi and their modification in cystic fibrosis: Impact of CFTR mutation (delF508).

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Chauvet, Sylvain; Traboulsi, Wael; Thevenon, Laura; Kouadri, Amal; Feige, Jean-Jacques; Camara, Boubou; Alfaidy, Nadia; Benharouga, Mohamed

2015-08-01

Enhanced lung angiogenesis has been reported in cystic fibrosis (CF). Recently, two highly homologous ligands, endocrine gland vascular endothelial growth factor (EG-VEGF) and mammalian Bv8, have been described as new angiogenic factors. Both ligands bind and activate two closely related G protein-coupled receptors, the prokineticin receptor (PROKR) 1 and 2. Yet, the expression, regulation, and potential role of EG-VEGF, BV8, and their receptors in normal and CF lung are still unknown. The expression of the receptors and their ligands was examined using molecular, biochemical, and immunocytochemistry analyses in lungs obtained from CF patients vs. control and in normal and CF bronchial epithelial cells. Cystic fibrosis transmembrane conductance regulator (CFTR) activity was evaluated in relation to both ligands, and concentrations of EG-VEGF were measured by ELISA. At the mRNA level, EG-VEGF, BV8, and PROKR2 gene expression was, respectively, approximately five, four, and two times higher in CF lungs compared with the controls. At the cellular level, both the ligands and their receptors showed elevated expressions in the CF condition. Similar results were observed at the protein level. The EG-VEGF secretion was apical and was approximately two times higher in CF compared with the normal epithelial cells. This secretion was increased following the inhibition of CFTR chloride channel activity. More importantly, EG-VEGF and BV8 increased the intracellular concentration of Ca(2+) and cAMP and stimulated CFTR-chloride channel activity. Altogether, these data suggest local roles for epithelial BV8 and EG-VEGF in the CF airway peribronchial vascular remodeling and highlighted the role of CFTR activity in both ligand biosynthesis and secretion. Copyright © 2015 the American Physiological Society.

Structure of the cystic fibrosis transmembrane conductance regulator in the inward-facing conformation revealed by single particle electron microscopy

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Ateeq Al-Zahrani

2015-05-01

Full Text Available The most common inherited disease in European populations is cystic fibrosis. Mutations in the gene lead to loss of function of the cystic fibrosis transmembrane conductance regulator protein (CFTR. CFTR is a member of the ATP-binding cassette family of membrane proteins that mostly act as active transporters using ATP to move substances across membranes. These proteins undergo large conformational changes during the transport cycle, consistent with an inward-facing to outward-facing translocation mechanism that was originally proposed by Jardetzky. CFTR is the only member of this family of proteins that functions as an ion channel, and in this case ATP and phosphorylation of a regulatory domain controls the opening of the channel. In this article we describe the inward-facing conformation of the protein and show it can be modulated by the presence of a purified recombinant NHERF1-PDZ1 domain that binds with high affinity to the CFTR C-terminal PDZ motif (-QDTRL. ATP hydrolysis activity of CFTR can also be modulated by glutathione, which we postulate may bind to the inward-facing conformation of the protein. A homology model for CFTR, based on a mitochondrial ABC transporter of glutathione in the inward-facing configuration has been generated. The map and the model are discussed with respect to the biology of the channel and the specific relationship between glutathione levels in the cell and CFTR. Finally, disease-causing mutations are mapped within the model and discussed in terms of their likely physiological effects.

Bioactivity-guided fractionation of an antidiarrheal Chinese herb Rhodiola kirilowii (Regel) Maxim reveals (-)-epicatechin-3-gallate and (-)-epigallocatechin-3-gallate as inhibitors of cystic fibrosis transmembrane conductance regulator.

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Chen, Lei; Yu, Bo; Zhang, Yaofang; Gao, Xin; Zhu, Liang; Ma, Tonghui; Yang, Hong

2015-01-01

Cystic fibrosis transmembrane conductance regulator (CFTR) is the principal apical route for transepithelial fluid transport induced by enterotoxin. Inhibition of CFTR has been confirmed as a pharmaceutical approach for the treatment of secretory diarrhea. Many traditional Chinese herbal medicines, like Rhodiola kirilowii (Regel) Maxim, have long been used for the treatment of secretory diarrhea. However, the active ingredients responsible for their therapeutic effectiveness remain unknown. The purpose of this study is to identify CFTR inhibitors from Rhodiola kirilowii (Regel) Maxim via bioactivity-directed isolation strategy. We first identified fractions of Rhodiola kirilowii (Regel) Maxim that inhibited CFTR Cl- channel activity. Further bioactivity-directed fractionation led to the identification of (-)-epigallocatechin-3-gallate (EGCG) as CFTR Cl- channel inhibitor. Analysis of 5 commercially available EGCG analogs including (+)-catechins (C), (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin-3-gallate (ECG) and EGCG revealed that ECG also had CFTR inhibitory activity. EGCG dose-dependently and reversibly inhibited CFTR Cl- channel activity in transfected FRT cells with an IC50 value around 100 μM. In ex vivo studies, EGCG and ECG inhibited CFTR-mediated short-circuit currents in isolated rat colonic mucosa in a dose-dependent manner. In an intestinal closed-loop model in mice, intraluminal application of EGCG (10 μg) and ECG (10 μg) significantly reduced cholera toxin-induced intestinal fluid secretion. CFTR Cl- channel is a molecular target of natural compounds EGCG and ECG. CFTR inhibition may account, at least in part, for the antidiarrheal activity of Rhodiola kirilowii (Regel) Maxim. EGCG and ECG could be new lead compounds for development of CFTR-related diseases such as secretory diarrhea.

N1303K (c.3909C>G) Mutation and Splicing: Implication of Its c.[744-33GATT(6); 869+11C>T] Complex Allele in CFTR Exon 7 Aberrant Splicing

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Farhat, Raëd; Puissesseau, Géraldine; El-Seedy, Ayman; Pasquet, Marie-Claude; Adolphe, Catherine; Corbani, Sandra; Megarbané, André; Kitzis, Alain; Ladeveze, Véronique

2015-01-01

Cystic Fibrosis is the most common recessive autosomal rare disease found in Caucasians. It is caused by mutations on the Cystic Fibrosis Transmembrane Conductance Regulator gene (CFTR) that encodes a protein located on the apical membrane of epithelial cells. c.3909C>G (p.Asn1303Lys, old nomenclature: N1303K) is one of the most common worldwide mutations. This mutation has been found at high frequencies in the Mediterranean countries with the highest frequency in the Lebanese population. Therefore, on the genetic level, we conducted a complete CFTR gene screening on c.3909C>G Lebanese patients. The complex allele c.[744-33GATT(6); 869+11C>T] was always associated with the c.3909C>G mutation in cis in the Lebanese population. In cellulo splicing studies, realized by hybrid minigene constructs, revealed no impact of the c.3909C>G mutation on the splicing process, whereas the associated complex allele induces minor exon skipping. PMID:26075213

Intra-individual biological variation in sweat chloride concentrations in CF, CFTR dysfunction, and healthy pediatric subjects.

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Cirilli, Natalia; Raia, Valeria; Rocco, Ilaria; De Gregorio, Fabiola; Tosco, Antonella; Salvadori, Laura; Sepe, Angela Ornella; Buzzetti, Roberto; Minicuci, Nadia; Castaldo, Giuseppe

2018-04-02

The sweat test is one of the main diagnostic tools used in newborn screening programs and as a confirmatory test, in case of suspect of Cystic Fibrosis (CF). Since sweat chloride (Cl) concentration is also considered an appropriate parameter to explore the efficacy of CFTR modulators in clinical trials, it is crucial to evaluate the biological variability of this test in healthy and pathological conditions. The aim of this pilot study was to determine the intra-individual biological variability of sweat Cl, both in healthy individuals and CF patients and to assess its correlation with diet, season, and menstrual cycle. Thirty-five out of 36 selected subjects (6-18 years) were enrolled by 2 CF care centers and assigned to 3 cohorts: CF, CFTR-related disorder (CFTR-RD) and healthy volunteers. Each participant was subjected to eight sweat tests in different conditions and time of the year. Data were analyzed using linear mixed effects models for repeated measures, taking also into account intra-individual correlations. We observed a high intra-individual variability of sweat Cl, with the lowest mean CV% values among CF patients (20.21 in CF, 29.74 in CFTR-RD, and 31.15 in healthy subjects). Gender and diet had no influence on sweat Cl variability, nor had pubertal age and menstrual phase. Results of this pilot study confirmed that sweat Cl variability is high in CF patients, although non-CF individuals displayed even higher mean CV% values. Season significantly influenced sweat test values only in CF patients, likely due to changes in their hydration status. © 2018 Wiley Periodicals, Inc.

Gap Junctions Are Involved in the Rescue of CFTR-Dependent Chloride Efflux by Amniotic Mesenchymal Stem Cells in Coculture with Cystic Fibrosis CFBE41o- Cells

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Annalucia Carbone

2018-01-01

Full Text Available We previously found that human amniotic mesenchymal stem cells (hAMSCs in coculture with CF immortalised airway epithelial cells (CFBE41o- line, CFBE on Transwell® filters acquired an epithelial phenotype and led to the expression of a mature and functional CFTR protein. In order to explore the role of gap junction- (GJ- mediated intercellular communication (GJIC in this rescue, cocultures (hAMSC : CFBE, 1 : 5 ratio were studied for the formation of GJIC, before and after silencing connexin 43 (Cx43, a major component of GJs. Functional GJs in cocultures were inhibited when the expression of the Cx43 protein was downregulated. Transfection of cocultures with siRNA against Cx43 resulted in the absence of specific CFTR signal on the apical membrane and reduction in the mature form of CFTR (band C, and in parallel, the CFTR-dependent chloride channel activity was significantly decreased. Cx43 downregulation determined also a decrease in transepithelial resistance and an increase in paracellular permeability as compared with control cocultures, implying that GJIC may regulate CFTR expression and function that in turn modulate airway epithelium tightness. These results indicate that GJIC is involved in the correction of CFTR chloride channel activity upon the acquisition of an epithelial phenotype by hAMSCs in coculture with CF cells.

Gap Junctions Are Involved in the Rescue of CFTR-Dependent Chloride Efflux by Amniotic Mesenchymal Stem Cells in Coculture with Cystic Fibrosis CFBE41o- Cells.

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Carbone, Annalucia; Zefferino, Roberto; Beccia, Elisa; Casavola, Valeria; Castellani, Stefano; Di Gioia, Sante; Giannone, Valentina; Seia, Manuela; Angiolillo, Antonella; Colombo, Carla; Favia, Maria; Conese, Massimo

2018-01-01

We previously found that human amniotic mesenchymal stem cells (hAMSCs) in coculture with CF immortalised airway epithelial cells (CFBE41o- line, CFBE) on Transwell® filters acquired an epithelial phenotype and led to the expression of a mature and functional CFTR protein. In order to explore the role of gap junction- (GJ-) mediated intercellular communication (GJIC) in this rescue, cocultures (hAMSC : CFBE, 1 : 5 ratio) were studied for the formation of GJIC, before and after silencing connexin 43 (Cx43), a major component of GJs. Functional GJs in cocultures were inhibited when the expression of the Cx43 protein was downregulated. Transfection of cocultures with siRNA against Cx43 resulted in the absence of specific CFTR signal on the apical membrane and reduction in the mature form of CFTR (band C), and in parallel, the CFTR-dependent chloride channel activity was significantly decreased. Cx43 downregulation determined also a decrease in transepithelial resistance and an increase in paracellular permeability as compared with control cocultures, implying that GJIC may regulate CFTR expression and function that in turn modulate airway epithelium tightness. These results indicate that GJIC is involved in the correction of CFTR chloride channel activity upon the acquisition of an epithelial phenotype by hAMSCs in coculture with CF cells.

Assembly and misassembly of cystic fibrosis transmembrane conductance regulator: folding defects caused by deletion of F508 occur before and after the calnexin-dependent association of membrane spanning domain (MSD) 1 and MSD2.

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Rosser, Meredith F N; Grove, Diane E; Chen, Liling; Cyr, Douglas M

2008-11-01

Cystic fibrosis transmembrane conductance regulator (CFTR) is a polytopic membrane protein that functions as a Cl(-) channel and consists of two membrane spanning domains (MSDs), two cytosolic nucleotide binding domains (NBDs), and a cytosolic regulatory domain. Cytosolic 70-kDa heat shock protein (Hsp70), and endoplasmic reticulum-localized calnexin are chaperones that facilitate CFTR biogenesis. Hsp70 functions in both the cotranslational folding and posttranslational degradation of CFTR. Yet, the mechanism for calnexin action in folding and quality control of CFTR is not clear. Investigation of this question revealed that calnexin is not essential for CFTR or CFTRDeltaF508 degradation. We identified a dependence on calnexin for proper assembly of CFTR's membrane spanning domains. Interestingly, efficient folding of NBD2 was also found to be dependent upon calnexin binding to CFTR. Furthermore, we identified folding defects caused by deletion of F508 that occurred before and after the calnexin-dependent association of MSD1 and MSD2. Early folding defects are evident upon translation of the NBD1 and R-domain and are sensed by the RMA-1 ubiquitin ligase complex.

Restoring Cystic Fibrosis Transmembrane Conductance Regulator Function Reduces Airway Bacteria and Inflammation in People with Cystic Fibrosis and Chronic Lung Infections.

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Hisert, Katherine B; Heltshe, Sonya L; Pope, Christopher; Jorth, Peter; Wu, Xia; Edwards, Rachael M; Radey, Matthew; Accurso, Frank J; Wolter, Daniel J; Cooke, Gordon; Adam, Ryan J; Carter, Suzanne; Grogan, Brenda; Launspach, Janice L; Donnelly, Seamas C; Gallagher, Charles G; Bruce, James E; Stoltz, David A; Welsh, Michael J; Hoffman, Lucas R; McKone, Edward F; Singh, Pradeep K

2017-06-15

Previous work indicates that ivacaftor improves cystic fibrosis transmembrane conductance regulator (CFTR) activity and lung function in people with cystic fibrosis and G551D-CFTR mutations but does not reduce density of bacteria or markers of inflammation in the airway. These findings raise the possibility that infection and inflammation may progress independently of CFTR activity once cystic fibrosis lung disease is established. To better understand the relationship between CFTR activity, airway microbiology and inflammation, and lung function in subjects with cystic fibrosis and chronic airway infections. We studied 12 subjects with G551D-CFTR mutations and chronic airway infections before and after ivacaftor. We measured lung function, sputum bacterial content, and inflammation, and obtained chest computed tomography scans. Ivacaftor produced rapid decreases in sputum Pseudomonas aeruginosa density that began within 48 hours and continued in the first year of treatment. However, no subject eradicated their infecting P. aeruginosa strain, and after the first year P. aeruginosa densities rebounded. Sputum total bacterial concentrations also decreased, but less than P. aeruginosa. Sputum inflammatory measures decreased significantly in the first week of treatment and continued to decline over 2 years. Computed tomography scans obtained before and 1 year after ivacaftor treatment revealed that ivacaftor decreased airway mucous plugging. Ivacaftor caused marked reductions in sputum P. aeruginosa density and airway inflammation and produced modest improvements in radiographic lung disease in subjects with G551D-CFTR mutations. However, P. aeruginosa airway infection persisted. Thus, measures that control infection may be required to realize the full benefits of CFTR-targeting treatments.

Interaction between a novel TGFB1 haplotype and CFTR genotype is associated with improved lung function in cystic fibrosis.

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Bremer, Lindsay A; Blackman, Scott M; Vanscoy, Lori L; McDougal, Kathryn E; Bowers, Amanda; Naughton, Kathleen M; Cutler, David J; Cutting, Garry R

2008-07-15

Cystic fibrosis (CF), the most common lethal single gene disorder in Caucasians, is due to mutations in the CFTR gene. Twin and sibling analysis indicates that modifier genes, rather than allelic variation in CFTR, are responsible for most of the variability in severity of lung disease, the major cause of mortality in CF patients. We used a family-based approach to test for association between lung function and two functional SNPs (rs1800469, '-509' and rs1982073, 'codon 10') in the 5' region of transforming growth factor-beta1 (TGFB1), a putative CF modifier gene. Quantitative transmission disequilibrium testing of 472 CF patient-parent-parent trios revealed that both TGFB1 SNPs showed significant transmission distortion when patients were stratified by CFTR genotype. Although lung function and nutritional status are correlated in CF patients, there was no evidence of association between the TGFB1 SNPs and variation in nutritional status. Additional tagging SNPs (rs8179181, rs2278422, rs8110090, rs4803455 and rs1982072) that capture most of the diversity in TGFB1 were also typed but none showed association with variation in lung function. However, a haplotype composed of the -509 C and codon 10 T alleles along with the C allele of the 3' SNP rs8179181 was highly associated with increased lung function in patients grouped by CFTR genotype. These results demonstrate that TGFB1 is a modifier of CF lung disease and reveal a previously unrecognized beneficial effect of TGFB1 variants upon the pulmonary phenotype.

Incidence and Carrier Frequency of CFTR Gene Mutations in Pregnancies With Echogenic Bowel in Nova Scotia and Prince Edward Island.

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Miller, Michelle E; Allen, Victoria M; Brock, Jo-Ann K

2018-03-01

Fetal echogenic bowel (echogenic bowel) is associated with cystic fibrosis (CF), with a reported incidence ranging from 1% to 13%. Prenatal testing for CF in the setting of echogenic bowel can be done by screening parental or fetal samples for pathogenic CFTR variants. If only one pathogenic variant is identified, sequencing of the CFTR gene can be undertaken, to identify a second pathogenic variant not covered in the standard screening panel. Full gene sequencing, however, also introduces the potential to identify variants of uncertain significance (VUSs) that can create counselling challenges and cause parental anxiety. To provide accurate counselling for families in the study population, the incidence of CF associated with echogenic bowel and the carrier frequency of CFTR variants were investigated. All pregnancies for which CF testing was undertaken for the indication of echogenic bowel (from Nova Scotia and Prince Edward Island) were identified (January 2007-July 2017). The CFTR screening and sequencing results were reviewed, and fetal outcomes related to CF were assessed. A total of 463 pregnancies with echogenic bowel were tested. Four were confirmed to be affected with CF, giving an incidence of 0.9% in this cohort. The carrier frequency of CF among all parents in the cohort was 5.0% (1 in 20); however, when excluding parents of affected fetuses, the carrier frequency for the population was estimated at 4.1% (1 in 25). CFTR gene sequencing identified an additional VUS in two samples. The incidence of CF in pregnancies with echogenic bowel in Nova Scotia and Prince Edward Island is 0.9%, with an estimated population carrier frequency of 4.1%. These results provide the basis for improved counselling to assess the risk of CF in the pregnancy, after parental carrier screening, using Bayesian probability. Counselling regarding VUSs should be undertaken before gene sequencing. Copyright © 2017 Society of Obstetricians and Gynaecologists of Canada. Published by

Sources of Variation in Sweat Chloride Measurements in Cystic Fibrosis

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Blackman, Scott M.; Raraigh, Karen S.; Corvol, Harriet; Rommens, Johanna M.; Pace, Rhonda G.; Boelle, Pierre-Yves; McGready, John; Sosnay, Patrick R.; Strug, Lisa J.; Knowles, Michael R.; Cutting, Garry R.

2016-01-01

Rationale: Expanding the use of cystic fibrosis transmembrane conductance regulator (CFTR) potentiators and correctors for the treatment of cystic fibrosis (CF) requires precise and accurate biomarkers. Sweat chloride concentration provides an in vivo assessment of CFTR function, but it is unknown the degree to which CFTR mutations account for sweat chloride variation. Objectives: To estimate potential sources of variation for sweat chloride measurements, including demographic factors, testing variability, recording biases, and CFTR genotype itself. Methods: A total of 2,639 sweat chloride measurements were obtained in 1,761 twins/siblings from the CF Twin-Sibling Study, French CF Modifier Gene Study, and Canadian Consortium for Genetic Studies. Variance component estimation was performed by nested mixed modeling. Measurements and Main Results: Across the tested CF population as a whole, CFTR gene mutations were found to be the primary determinant of sweat chloride variability (56.1% of variation) with contributions from variation over time (e.g., factors related to testing on different days; 13.8%), environmental factors (e.g., climate, family diet; 13.5%), other residual factors (e.g., test variability; 9.9%), and unique individual factors (e.g., modifier genes, unique exposures; 6.8%) (likelihood ratio test, P < 0.001). Twin analysis suggested that modifier genes did not play a significant role because the heritability estimate was negligible (H2 = 0; 95% confidence interval, 0.0–0.35). For an individual with CF, variation in sweat chloride was primarily caused by variation over time (58.1%) with the remainder attributable to residual/random factors (41.9%). Conclusions: Variation in the CFTR gene is the predominant cause of sweat chloride variation; most of the non-CFTR variation is caused by testing variability and unique environmental factors. If test precision and accuracy can be improved, sweat chloride measurement could be a valuable biomarker

Compounds that correct F508del-CFTR trafficking can also correct other protein trafficking diseases: an in vitro study using cell lines

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Sampson Heidi M

2013-01-01

Full Text Available Abstract Background Many genetic diseases are due to defects in protein trafficking where the mutant protein is recognized by the quality control systems, retained in the endoplasmic reticulum (ER, and degraded by the proteasome. In many cases, the mutant protein retains function if it can be trafficked to its proper cellular location. We have identified structurally diverse correctors that restore the trafficking and function of the most common mutation causing cystic fibrosis, F508del-CFTR. Most of these correctors do not act directly as ligands of CFTR, but indirectly on other pathways to promote folding and correction. We hypothesize that these proteostasis regulators may also correct other protein trafficking diseases. Methods To test our hypothesis, we used stable cell lines or transient transfection to express 2 well-studied trafficking disease mutations in each of 3 different proteins: the arginine-vasopressin receptor 2 (AVPR2, also known as V2R, the human ether-a-go-go-related gene (KCNH2, also known as hERG, and finally the sulfonylurea receptor 1 (ABCC8, also known as SUR1. We treated cells expressing these mutant proteins with 9 structurally diverse F508del-CFTR correctors that function through different cellular mechanisms and assessed whether correction occurred via immunoblotting and functional assays. Results were deemed significantly different from controls by a one-way ANOVA (p  Results Here we show that F508del-CFTR correctors RDR1, KM60 and KM57 also correct some mutant alleles of other protein trafficking diseases. We also show that one corrector, the cardiac glycoside ouabain, was found to alter the glycosylation of all mutant alleles tested. Conclusions Correctors of F508del-CFTR trafficking might have broader applications to other protein trafficking diseases.

Sweat chloride and immunoreactive trypsinogen in infants carrying two CFTR mutations and not affected by cystic fibrosis.

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Castellani, Carlo; Tridello, Gloria; Tamanini, Anna; Assael, Baroukh M

2017-07-01

Newborns with raised immunotrypsinogen levels who have non-pathological sweat chloride values and carry two cystic fibrosis transmembrane regulator ( CFTR ) mutations of which at least one is not acknowledged to be cystic fibrosis (CF)-causing are at risk of developing clinical manifestations consistent with CFTR-related disorders or even CF. It is not known whether newborns with similar genotypes and normal immunoreactive trypsinogen (IRT) may share the same risk. This study found that newborns with these characteristics and normal IRT have lower sweat chloride values than those with raised IRT (p=0.007). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Conductive component after cochlear implantation in patients with residual hearing conservation.

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Chole, Richard A; Hullar, Timothy E; Potts, Lisa G

2014-12-01

Changes in auditory thresholds following cochlear implantation are generally assumed to be due to damage to neural elements. Theoretical studies have suggested that placement of a cochlear implant can cause a conductive hearing loss. Identification of a conductive component following cochlear implantation could guide improvements in surgical techniques or device designs. The purpose of this study is to characterize new-onset conductive hearing losses after cochlear implantation. In a prospective study, air- and bone-conduction audiometric testing were completed on cochlear implant recipients. An air-bone gap equal to or greater than 15 dB HL at 2 frequencies determined the presence of a conductive component. Of the 32 patients with preoperative bone-conduction hearing, 4 patients had a new-onset conductive component resulting in a mixed hearing loss, with air-conduction thresholds ranging from moderate to profound and an average air-bone gap of 30 dB HL. One had been implanted through the round window, 2 had an extended round window, and 1 had a separate cochleostomy. Loss of residual hearing following cochlear implantation may be due in part to a conductive component. Identifying the mechanism for this conductive component may help minimize hearing loss. Postoperative hearing evaluation should measure both air- and bone-conduction thresholds.

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

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Sánchez, Karen; de Mendonca, Elizabeth; Matute, Xiorama; Chaustre, Ismenia; Villalón, Marlene; Takiff, Howard

2016-01-01

The mutations in the CFTR gene found in patients with cystic fibrosis (CF) have geographic differences, but there are scant data on their prevalence in Venezuelan patients. This study determined the frequency of common CFTR gene mutations in a group of Venezuelan patients with CF. The 27 exons of the CFTR gene from 110 Venezuelan patients in the National CF Program were amplified and sequenced. A total of 36 different mutations were identified, seven with frequencies greater than 1%: p.Phe508del (27.27%), p.Gly542* (3.18%), c.2988+1G>A (3.18%), p.Arg334Trp (1.36%), p.Arg1162* (1.36%), c.1-8G>C (1.36%), and p.[Gly628Arg;Ser1235Arg](1.36). In 40% of patients, all with a clinical diagnosis of CF, no mutations were found. This report represents the largest cohort of Venezuelan patients with CF ever examined, and includes a wider mutation panel than has been previously studied in this population. Mutations common in Southern European populations predominate, and several new mutations were discovered, but no mutations were found in 40% of the cohort.

Benign and Deleterious Cystic Fibrosis Transmembrane Conductance Regulator Mutations Identified by Sequencing in Positive Cystic Fibrosis Newborn Screen Children from California.

Science.gov (United States)

Salinas, Danieli B; Sosnay, Patrick R; Azen, Colleen; Young, Suzanne; Raraigh, Karen S; Keens, Thomas G; Kharrazi, Martin

2016-01-01

Of the 2007 Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) mutations, 202 have been assigned disease liability. California's racially diverse population, along with CFTR sequencing as part of newborn screening model, provides the opportunity to examine the phenotypes of children with uncategorized mutations to help inform disease liability and penetrance. We conducted a retrospective cohort study based on children screened from 2007 to 2011 and followed for two to six years. Newborns that screened positive were divided into three genotype groups: those with two CF-causing mutations (CF-C); those with one mutation of varying clinic consequence (VCC); and those with one mutation of unknown disease liability (Unknown). Sweat chloride tests, pancreatic sufficiency status, and Pseudomonas aeruginosa colonization were compared. Children with two CF-causing mutations had a classical CF phenotype, while 5% of VCC (4/78) and 11% of Unknown (27/244) met diagnostic criteria of CF. Children carrying Unknown mutations 2215insG with D836Y, and T1036N had early and classical CF phenotype, while others carrying 1525-42G>A, L320V, L967S, R170H, and 296+28A>G had a benign clinical presentation, suggesting that these are non-CF causing. While most infants with VCC and Unknown CFTR mutations do not meet diagnostic criteria for CF, a small proportion do. These findings highlight the range of genotypes and phenotypes in the first few years of life following CF newborn screening when CFTR sequencing is performed.

Combinatorial effects of genistein and sex-steroids on the level of cystic fibrosis transmembrane regulator (CFTR), adenylate cyclase (AC) and cAMP in the cervix of ovariectomised rats.

Science.gov (United States)

Salleh, Naguib; Ismail, Nurain; Muniandy, Sekaran; Korla, Praveen Kumar; Giribabu, Nelli

2015-12-01

The combinatorial effects of genistein and estrogen (E) or estrogen plus progesterone (E+P) on CFTR, AC and cAMP levels in cervix were investigated. Ovariectomised adult female rats received 50 or 100mg/kg/day genistein with E or E followed by E+P [E+(E+P)] for seven consecutive days. Cervixes were harvested and analyzed for CFTR mRNA levels by Real-time PCR. Distribution of AC and CFTR proteins in endocervix were observed by immunohistochemistry. Levels of cAMP were measured by enzyme-immunoassay. Molecular docking predicted interaction between genistein and AC. Our results indicate that levels of CFTR, AC and cAMP in cervix of rats receiving genistein plus E were higher than E-only treatment (pcervix of E and E+(E+P)-treated rats by genistein could affect the cervical secretory function which could influence the female reproductive processes. Copyright © 2015 Elsevier Inc. All rights reserved.

Increased cystic fibrosis transmembrane conductance regulators expression and decreased epithelial sodium channel alpha subunits expression in early abortion: findings from a mouse model and clinical cases of abortion.

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Min Zhou

Full Text Available The status of the maternal endometrium is vital in regulating humoral homeostasis and for ensuring embryo implantation. Cystic fibrosis transmembrane conductance regulators (CFTR and epithelial sodium channel alpha subunits (ENaC-α play an important role in female reproduction by maintaining humoral and cell homeostasis. However, it is not clear whether the expression levels of CFTR and ENaC-α in the decidual component during early pregnancy are related with early miscarriage. CBA×DBA/2 mouse mating has been widely accepted as a classical model of early miscarriage. The abortion rate associated with this mating was 33.33% in our study. The decidua of abortion-prone CBA female mice (DBA/2 mated had higher CFTR mRNA and protein expression and lower ENaC-α mRNA and protein expression, compared to normal pregnant CBA mice (BLAB/C mated. Furthermore, increased CFTR expression and decreased ENaC-α expression were observed in the uterine tissue from women with early miscarriage, as compared to those with successful pregnancy. In conclusion, increased CFTR expression and decreased ENaC-α expression in the decidua of early abortion may relate with failure of early pregnancy.

Differential expression of gill Na⁺,K⁺-ATPase alpha- and beta-subunits, Na⁺,K⁺,2Cl^- cotransporter and CFTR anion channel in juvenile anadromous and landlocked Atlantic salmon Salmo salar

DEFF Research Database (Denmark)

Nilsen, Tom O.; Ebbesson, Lars O. E.; Madsen, Steffen S.

2007-01-01

This study examines changes in gill Na(+),K(+)-ATPase (NKA) alpha- and beta-subunit isoforms, Na(+),K(+),2Cl(-) cotransporter (NKCC) and cystic fibrosis transmembrane conductance regulator (CFTR I and II) in anadromous and landlocked strains of Atlantic salmon during parr-smolt transformation, an...

Benign and Deleterious Cystic Fibrosis Transmembrane Conductance Regulator Mutations Identified by Sequencing in Positive Cystic Fibrosis Newborn Screen Children from California.

Directory of Open Access Journals (Sweden)

Danieli B Salinas

Full Text Available Of the 2007 Cystic Fibrosis Transmembrane Conductance Regulator (CFTR mutations, 202 have been assigned disease liability. California's racially diverse population, along with CFTR sequencing as part of newborn screening model, provides the opportunity to examine the phenotypes of children with uncategorized mutations to help inform disease liability and penetrance.We conducted a retrospective cohort study based on children screened from 2007 to 2011 and followed for two to six years. Newborns that screened positive were divided into three genotype groups: those with two CF-causing mutations (CF-C; those with one mutation of varying clinic consequence (VCC; and those with one mutation of unknown disease liability (Unknown. Sweat chloride tests, pancreatic sufficiency status, and Pseudomonas aeruginosa colonization were compared.Children with two CF-causing mutations had a classical CF phenotype, while 5% of VCC (4/78 and 11% of Unknown (27/244 met diagnostic criteria of CF. Children carrying Unknown mutations 2215insG with D836Y, and T1036N had early and classical CF phenotype, while others carrying 1525-42G>A, L320V, L967S, R170H, and 296+28A>G had a benign clinical presentation, suggesting that these are non-CF causing.While most infants with VCC and Unknown CFTR mutations do not meet diagnostic criteria for CF, a small proportion do. These findings highlight the range of genotypes and phenotypes in the first few years of life following CF newborn screening when CFTR sequencing is performed.

Cystic Fibrosis Transmembrane Conductance Regulator Attaches Tumor Suppressor PTEN to the Membrane and Promotes Anti Pseudomonas aeruginosa Immunity.

Science.gov (United States)

Riquelme, Sebastián A; Hopkins, Benjamin D; Wolfe, Andrew L; DiMango, Emily; Kitur, Kipyegon; Parsons, Ramon; Prince, Alice

2017-12-19

The tumor suppressor PTEN controls cell proliferation by regulating phosphatidylinositol-3-kinase (PI3K) activity, but the participation of PTEN in host defense against bacterial infection is less well understood. Anti-inflammatory PI3K-Akt signaling is suppressed in patients with cystic fibrosis (CF), a disease characterized by hyper-inflammatory responses to airway infection. We found that Ptenl -/- mice, which lack the NH 2 -amino terminal splice variant of PTEN, were unable to eradicate Pseudomonas aeruginosa from the airways and could not generate sufficient anti-inflammatory PI3K activity, similar to what is observed in CF. PTEN and the CF transmembrane conductance regulator (CFTR) interacted directly and this interaction was necessary to position PTEN at the membrane. CF patients under corrector-potentiator therapy, which enhances CFTR transport to the membrane, have increased PTEN amounts. These findings suggest that improved CFTR trafficking could enhance P. aeruginosa clearance from the CF airway by activating PTEN-mediated anti-bacterial responses and might represent a therapeutic strategy. Published by Elsevier Inc.

Identification of eight novel mutations in a collaborative analysis of a part of the second transmembrane domain of the CFTR gene

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Mercier, B.; Audrezet, M.P.; Guillermit, H.; Quere, I.; Verlingue, C.; Ferec, C. (CDTS, Brest (France)); Lissens, W.; Bonduelle, M.; Liebaers, I. (University Hospital VUB, Brussels (Belgium)); Novelli, G.; Sangiuolo, F.; Dallapiccola, B. (IRCCS, Rotondo (Italy)); Kalaydjieva, L. (Inst. of Obstetrics, Sofia (Bulgaria)); Arce, M. De; Cashman, S. (Trinity College, Dublin (Ireland)); Kapranov, N. (NRC of medical Genetics, Moscow (Russian Federation)); Canki Klain, N. (Tozd Univerzitetna Ginekoloska Klinika, Ljubljana (Yugoslavia)); Lenoir, G. (Hopital des Enfants Malades Necker, Paris (France)); Chauveau, P. (Centre Hospitalier General, Le Havre (France)); Lanaerts, C. (Centre Hospitalier Regional et Universitaire, Amiens (France)); Rault, G. (Centre Helio-Marin, Roscoff (France))

1993-04-01

Cystic fibrosis transmembrane conductance regulator (CFTR), the gene responsible, when mutated, for cystic fibrosis (CF), spans over 230 kb on the long arm of chromosome 7 and is composed of 27 exons. The most common mutation responsible for CF worldwide is the deletion of a phenylalanine amino acid at codon 508 in the first nucleotide-binding fold and accounts for approximately 70% of CF chromosomes studied. More than 250 other mutations have been reported through the CF Genetic Analysis Consortium. The majority of the mutations previously described lie in the two nucleotide-binding folds. To explore exhaustively other regions of the gene, particularly exons coding for transmembrane domains, the authors have initiated a collaborative study between different laboratories to screen 369 non-[Delta]F508 CF chromosomes of seven ethnic European populations (Belgian, French, Breton, Irish, Italian, Yugoslavian, Russian). Among these chromosomes carrying an unidentified mutation, 63 were from Brittany, 50 of various French origin, 45 of Irish origin, 56 of Italian origin, 41 of Belgian origin, 2 of Turkish origin, 38 of Yugoslavian origin, 22 of Russian origin, and 52 of Bulgarian origin. Diagnostic criteria for CF included at least one positive sweat test and pulmonary disease with or without pancreatic disease. Using a denaturing gradient gel electrophoresis (DGGE) assay, they have identified eight novel mutations in exon 17b coding for part of the second transmembrane domain of the CFTR and they describe them in this report. 8 refs., 1 fig., 1 tab.

Spectrum of CFTR gene mutations in Ecuadorian cystic fibrosis patients: the second report of the p.H609R mutation.

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Ortiz, Sofía C; Aguirre, Santiago J; Flores, Sofía; Maldonado, Claudio; Mejía, Juan; Salinas, Lilian

2017-11-01

High heterogeneity in the CFTR gene mutations disturbs the molecular diagnosis of cystic fibrosis (CF). In order to improve the diagnosis of CF in our country, the present study aims to define a panel of common CFTR gene mutations by sequencing 27 exons of the gene in Ecuadorian Cystic Fibrosis patients. Forty-eight Ecuadorian individuals with suspected/confirmed CF diagnosis were included. Twenty-seven exons of CFTR gene were sequenced to find sequence variations. Prevalence of pathogenic variations were determined and compared with other countries' data. We found 70 sequence variations. Eight of these are CF-causing mutations: p.F508del, p.G85E, p.G330E, p.A455E, p.G970S, W1098X, R1162X, and N1303K. Also this study is the second report of p.H609R in Ecuadorian population. Mutation prevalence differences between Ecuadorian population and other Latin America countries were found. The panel of mutations suggested as an initial screening for the Ecuadorian population with cystic fibrosis should contain the mutations: p.F508del, p.G85E, p.G330E, p.A455E, p.G970S, W1098X, R1162X, and N1303K. © 2017 NETLAB Laboratorios Especializados. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.

The effect of NO-donors on chloride efflux, intracellular Ca(2+) concentration and mRNA expression of CFTR and ENaC in cystic fibrosis airway epithelial cells.

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Oliynyk, Igor; Hussain, Rashida; Amin, Ahmad; Johannesson, Marie; Roomans, Godfried M

2013-06-01

Since previous studies showed that the endogenous bronchodilator, S-nitrosglutathione (GSNO), caused a marked increase in CFTR-mediated chloride (Cl(-)) efflux and improved the trafficking of CFTR to the plasma membrane, and that also the nitric oxide (NO)-donor GEA3162 had a similar, but smaller, effect on Cl(-) efflux, it was investigated whether the NO-donor properties of GSNO were relevant for its effect on Cl(-) efflux from airway epithelial cells. Hence, the effect of a number of other NO-donors, sodium nitroprusside (SNP), S-nitroso-N-acetyl-DL-penicillamine (SNAP), diethylenetriamine/nitric oxide adduct (DETA-NO), and diethylenetriamine/nitric oxide adduct (DEA-NONOate) on Cl(-) efflux from CFBE (∆F508/∆F508-CFTR) airway epithelial cells was tested. Cl(-) efflux was determined using the fluorescent N-(ethoxycarbonylmethyl)-6-methoxyquinoliniu bromide (MQAE)-technique. Possible changes in the intracellular Ca(2+) concentration were tested by the fluorescent fluo-4 method in a confocal microscope system. Like previously with GSNO, after 4 h incubation with the NO-donor, an increased Cl(-) efflux was found (in the order SNAP>DETA-NO>SNP). The effect of DEA-NONOate on Cl(-) efflux was not significant, and the compound may have (unspecific) deleterious effects on the cells. Again, as with GSNO, after a short (5 min) incubation, SNP had no significant effect on Cl(-) efflux. None of the NO-donors that had a significant effect on Cl(-) efflux caused significant changes in the intracellular Ca(2+) concentration. After 4 h preincubation, SNP caused a significant increase in the mRNA expression of CFTR. SNAP and DEA-NONOate decreased the mRNA expression of all ENaC subunits significantly. DETA-NO caused a significant decrease only in α-ENaC expression. After a short preincubation, none of the NO-donors had a significant effect, neither on the expression of CFTR, nor on that of the ENaC subunits in the presence and absence of L-cysteine. It can be concluded that

Clusters of Cl- channels in CFTR-expressing em>Sf>9 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

channel. Excised outside-out patches of CFTR-infected and forskolin-stimulated cells exhibited wave-like gating kinetics of well-resolved current transitions. All-point Gaussian distributions revealed contributions from several (five to nine) identical channels. Such channels, in excised outside...

A large-scale study of the random variability of a coding sequence: a study on the CFTR gene.

Science.gov (United States)

Modiano, Guido; Bombieri, Cristina; Ciminelli, Bianca Maria; Belpinati, Francesca; Giorgi, Silvia; Georges, Marie des; Scotet, Virginie; Pompei, Fiorenza; Ciccacci, Cinzia; Guittard, Caroline; Audrézet, Marie Pierre; Begnini, Angela; Toepfer, Michael; Macek, Milan; Ferec, Claude; Claustres, Mireille; Pignatti, Pier Franco

2005-02-01

Coding single nucleotide substitutions (cSNSs) have been studied on hundreds of genes using small samples (n(g) approximately 100-150 genes). In the present investigation, a large random European population sample (average n(g) approximately 1500) was studied for a single gene, the CFTR (Cystic Fibrosis Transmembrane conductance Regulator). The nonsynonymous (NS) substitutions exhibited, in accordance with previous reports, a mean probability of being polymorphic (q > 0.005), much lower than that of the synonymous (S) substitutions, but they showed a similar rate of subpolymorphic (q < 0.005) variability. This indicates that, in autosomal genes that may have harmful recessive alleles (nonduplicated genes with important functions), genetic drift overwhelms selection in the subpolymorphic range of variability, making disadvantageous alleles behave as neutral. These results imply that the majority of the subpolymorphic nonsynonymous alleles of these genes are selectively negative or even pathogenic.

Impact of the CFTR-potentiator ivacaftor on airway microbiota in cystic fibrosis patients carrying a G551D mutation.

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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.

[Frequency of the most common mutations of the CFTR gene in peruvian patients with cystic fibrosis using the ARMS-PCR technique].

Science.gov (United States)

Aquino, Ruth; Protzel, Ana; Rivera, Juan; Abarca, Hugo; Dueñas, Milagros; Nestarez, Cecilia; Purizaga, Nestor; Diringer, Benoit

2017-01-01

To determine the frequency of the ten most common mutations of the CFTR gene reported in Latin Americausing amplification-refractory mutation system-polymerase chain reaction (ARMS-PCR) in patients with cystic fibrosis (CF) in two referral hospitals in Peru during the year 2014. The frequency of the ten most common mutations of the CFTR gene was assessed in patients of the Hospital Nacional Edgardo Rebagliati Martins and the Instituto Nacional de Salud del Niño, both located in Lima, Peru. Blood samples were collected from 36 patients with CF, and the ARMS-PCR technique was used to determine the presence of these mutations. The study group included 73.5% of patients with a known diagnosis of CF in the country when the study was carried out. ARMS-PCR allowed three of the mutations to be identified in a combined 30.6% of the alleles from patients with CF, and 64.9% of the mutated alleles were not identified. The mutations found were p.Phe508del (22,2%), p.Gly542* (6,9%), and p.Arg1162* (1,4%). There is significant variability in both the frequency and type of mutations present in our study population and in what has been reported in other Latin American countries. It is necessary to perform studies that use complete sequencing technology for the CFTR gene to identify other mutations present in our population.

The importance of functional tests to assess the effect of a new CFTR variant when genotype-phenotype correlation is not possible.

Science.gov (United States)

Hinzpeter, Alexandre; Reboul, Marie-Pierre; Callebaut, Isabelle; Zordan, Cécile; Costes, Bruno; Guichoux, Julie; Iron, Albert; Lacombe, Didier; Martin, Natacha; Arveiler, Benoit; Fanen, Pascale; Fergelot, Patricia; Girodon, Emmanuelle

2017-05-01

In vitro functional tests aimed to investigate CFTR dysfunction appear critical to help elucidate the functional impact of new variants of uncertain clinical significance and solve inconclusive cases, especially in early deceased newborns.

Curcumin/poly(2-methyl-2-oxazoline-b-tetrahydrofuran-b-2-methyl-2-oxazoline) formulation: An improved penetration and biological effect of curcumin in F508del-CFTR cell lines.

Science.gov (United States)

Gonçalves, Cristine; Gomez, Jean-Pierre; Même, William; Rasolonjatovo, Bazoly; Gosset, David; Nedellec, Steven; Hulin, Philippe; Huin, Cécile; Le Gall, Tony; Montier, Tristan; Lehn, Pierre; Pichon, Chantal; Guégan, Philippe; Cheradame, Hervé; Midoux, Patrick

2017-08-01

Neutral amphiphilic triblock ABA copolymers are of great interest to solubilize hydrophobic drugs. We reported that a triblock ABA copolymer consisting of methyl-2-oxazoline (MeOx) and tetrahydrofuran (THF) (MeOx 6 -THF 19 -MeOx 6 ) (TBCP2) can solubilize curcumin (Cur) a very hydrophobic molecule exhibiting multiple therapeutic effects but whose insolubility and low stability in water is a major drawback for clinical applications. Here, we provide evidences by flow cytometry and confocal microscopy that Cur penetration in normal and ΔF508-CFTR human airway epithelial cell lines is facilitated by TBCP2. When used on ΔF508-CFTR cell lines, the Cur/TBCP2 formulation promotes the restoration of the expression of the CFTR protein in the plasma membrane. Furthermore, patch-clamp and MQAE fluorescence experiments show that this effect is associated with a correction of a Cl - selective current at the membrane surface of F508del-CFTR cells. The results show the great potential of the neutral amphiphilic triblock copolymer MeOx 6 -THF 19 -MeOx 6 as carrier for curcumin in a Cystic Fibrosis context. We anticipate that other MeOx n -THF m -MeOx n copolymers could have similar behaviours for other highly insoluble therapeutic drugs or cosmetic active ingredients. Copyright © 2017 Elsevier B.V. All rights reserved.

Frecuencia de las mutaciones más comunes del gen CFTR en pacientes peruanos con fibrosis quística mediante la técnica ARMS-PCR

OpenAIRE

Aquino, Ruth; Protzel, Ana; Rivera, Juan; Abarca, Hugo; Dueñas, Milagros; Nestarez, Cecilia; Purizaga, Nestor; Diringer, Benoit

2017-01-01

Objetivos. Determinar la frecuencia de las diez mutaciones más comúnmente reportadas en América Latina del gen CFTR mediante Sistema de Mutación Refractario a la amplificación por PCR (ARMS-PCR) en los pacientes con fibrosis quística (FQ) de dos instituciones hospitalarias de referencia en el Perú durante el año 2014. Materiales y métodos. Se evaluó la frecuencia de las diez comúnmente reportadas más comúnmente reportadas del gen CFTR en los pacientes del Hospital Nacional Edgardo Rebagliati ...

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

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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.

Identification of insecticide residues with a conducting-polymer electronic nose

Science.gov (United States)

A.D. Wilson

2014-01-01

The identification of insecticide residues on crop foliage is needed to make periodic pest management decisions. Electronic-nose (e-nose) methods were developed and tested as a means of acquiring rapid identifications of insecticide residue types at relatively low cost by detection of headspace volatiles released from inert surfaces in vitro. Detection methods were...

Influence of the cystic fibrosis transmembrane conductance regulator on expression of lipid metabolism-related genes in dendritic cells

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Quadri Luis EN

2009-04-01

Full Text Available Abstract Background Cystic fibrosis (CF is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR gene. Infections of the respiratory tract are a hallmark in CF. The host immune responses in CF are not adequate to eradicate pathogens, such as P. aeruginosa. Dendritic cells (DC are crucial in initiation and regulation of immune responses. Changes in DC function could contribute to abnormal immune responses on multiple levels. The role of DC in CF lung disease remains unknown. Methods This study investigated the expression of CFTR gene in bone marrow-derived DC. We compared the differentiation and maturation profile of DC from CF and wild type (WT mice. We analyzed the gene expression levels in DC from naive CF and WT mice or following P. aeruginosa infection. Results CFTR is expressed in DC with lower level compared to lung tissue. DC from CF mice showed a delayed in the early phase of differentiation. Gene expression analysis in DC generated from naive CF and WT mice revealed decreased expression of Caveolin-1 (Cav1, a membrane lipid raft protein, in the CF DC compared to WT DC. Consistently, protein and activity levels of the sterol regulatory element binding protein (SREBP, a negative regulator of Cav1 expression, were increased in CF DC. Following exposure to P. aeruginosa, expression of 3β-hydroxysterol-Δ7 reductase (Dhcr7 and stearoyl-CoA desaturase 2 (Scd2, two enzymes involved in the lipid metabolism that are also regulated by SREBP, was less decreased in the CF DC compared to WT DC. Conclusion These results suggest that CFTR dysfunction in DC affects factors involved in membrane structure and lipid-metabolism, which may contribute to the abnormal inflammatory and immune response characteristic of CF.

Conductivity Profile Determination by Eddy Current for Shot Peened Superalloy Surfaces Toward Residual Stress Assessment

International Nuclear Information System (INIS)

Shen, Y.; Lo, C. C. H.; Frishman, A. M.; Lee, C.; Nakagawa, N.

2007-01-01

This paper describes an eddy current model-based method for inverting near-surface conductivity deviation profiles of surface treated materials from swept-high frequency eddy current (SHFEC) data. This work forms part of our current research directed towards the development of an electromagnetic nondestructive technique for assessing residual stress of shot-peened superalloy components. The inversion procedure is based on the use of a parameterized function to describe the near-surface conductivity as a function of depth for a shot-peened surface, and the laterally uniform multi-layer theory of Cheng, Dodd and Deeds to calculate the resulting coil impedance deviations. The convergence of the inversion procedure has been tested against synthesized eddy current data. As a demonstration, the conductivity deviation profiles of a series of Inconel 718 specimens, shot peened at various Almen intensities, have been obtained by inversion. Several consistency tests were conducted to examine the reliability of the inverted conductivity profiles. The results show that conductivity deviation profiles can be reliably determined from SHFEC data within the accuracy of the current measurement system

Airway epithelial cell exposure to distinct e-cigarette liquid flavorings reveals toxicity thresholds and activation of CFTR by the chocolate flavoring 2,5-dimethypyrazine.

Science.gov (United States)

Sherwood, Cara L; Boitano, Scott

2016-05-17

that the increases in ion conductance evoked by 2,5-dimethylpyrazine were largely attributed to a protein kinase A-dependent (PKA) activation of the cystic fibrosis transmembrane conductance regulator (CFTR) ion channel. Data from our high-capacity screening assays demonstrates that individual e-cigarette liquid flavoring chemicals vary in their cytotoxicity profiles and that some constituents evoke a cellular physiological response on their own independent of cell death. The activation of CFTR by 2,5-dimethylpyrazine may have detrimental consequences for airway surface liquid homeostasis in individuals that use e-cigarettes habitually.

Molecular mechanisms of reduced glutathione transport: role of the MRP/CFTR/ABCC and OATP/SLC21A families of membrane proteins

International Nuclear Information System (INIS)

Ballatori, Nazzareno; Hammond, Christine L.; Cunningham, Jennifer B.; Krance, Suzanne M.; Marchan, Rosemarie

2005-01-01

The initial step in reduced glutathione (GSH) turnover in all mammalian cells is its transport across the plasma membrane into the extracellular space; however, the mechanisms of GSH transport are not clearly defined. GSH export is required for the delivery of its constituent amino acids to other tissues, detoxification of drugs, metals, and other reactive compounds of both endogenous and exogenous origin, protection against oxidant stress, and secretion of hepatic bile. Recent studies indicate that some members of the multidrug resistance-associated protein (MRP/CFTR or ABCC) family of ATP-binding cassette (ABC) proteins, as well as some members of the organic anion transporting polypeptide (OATP or SLC21A) family of transporters contribute to this process. In particular, five of the 12 members of the MRP/CFTR family appear to mediate GSH export from cells namely, MRP1, MRP2, MRP4, MRP5, and CFTR. Additionally, two members of the OATP family, rat Oatp1 and Oatp2, have been identified as GSH transporters. For the Oatp1 transporter, efflux of GSH may provide the driving force for the uptake of extracellular substrates. In humans, OATP-B and OATP8 do not appear to transport GSH; however, other members of this family have yet to be characterized in regards to GSH transport. In yeast, the ABC proteins Ycf1p and Bpt1p transport GSH from the cytosol into the vacuole, whereas Hgt1p mediates GSH uptake across the plasma membrane. Because transport is a key step in GSH homeostasis and is intimately linked to its biological functions, GSH export proteins are likely to modulate essential cellular functions

Identification and discrimination of herbicide residues using a conducting polymer electronic nose

Science.gov (United States)

Alphus Dan Wilson

2016-01-01

The identification of herbicide residues on crop foliage is necessary to make crop-management decisions for weed pest control and to monitor pesticide residue levels on food crops. Electronic-nose (e-nose) methods were tested as a cheaper, alternative means of discriminating between herbicide residue types (compared with conventional chromatography methods), by...

Stereochemical determinants of C-terminal specificity in PDZ peptide-binding domains: a novel contribution of the carboxylate-binding loop.

Science.gov (United States)

Amacher, Jeanine F; Cushing, Patrick R; Bahl, Christopher D; Beck, Tobias; Madden, Dean R

2013-02-15

PDZ (PSD-95/Dlg/ZO-1) binding domains often serve as cellular traffic engineers, controlling the localization and activity of a wide variety of binding partners. As a result, they play important roles in both physiological and pathological processes. However, PDZ binding specificities overlap, allowing multiple PDZ proteins to mediate distinct effects on shared binding partners. For example, several PDZ domains bind the cystic fibrosis (CF) transmembrane conductance regulator (CFTR), an epithelial ion channel mutated in CF. Among these binding partners, the CFTR-associated ligand (CAL) facilitates post-maturational degradation of the channel and is thus a potential therapeutic target. Using iterative optimization, we previously developed a selective CAL inhibitor peptide (iCAL36). Here, we investigate the stereochemical basis of iCAL36 specificity. The crystal structure of iCAL36 in complex with the CAL PDZ domain reveals stereochemical interactions distributed along the peptide-binding cleft, despite the apparent degeneracy of the CAL binding motif. A critical selectivity determinant that distinguishes CAL from other CFTR-binding PDZ domains is the accommodation of an isoleucine residue at the C-terminal position (P(0)), a characteristic shared with the Tax-interacting protein-1. Comparison of the structures of these two PDZ domains in complex with ligands containing P(0) Leu or Ile residues reveals two distinct modes of accommodation for β-branched C-terminal side chains. Access to each mode is controlled by distinct residues in the carboxylate-binding loop. These studies provide new insights into the primary sequence determinants of binding motifs, which in turn control the scope and evolution of PDZ interactomes.

Electrical conductivity of the screening residuals of coke production in context of ferrochromium production in a submerged arc furnace

Energy Technology Data Exchange (ETDEWEB)

Rousu, Arto; Mattila, Olli [Lab. of Process Metallurgy, Univ. of Oulu (Finland)

2009-11-15

Coke is used as a reducing agent in the production of ferrochromium in a submerged arc furnace (SAF). Its good electrical conductivity compared to other input materials makes it a dominant current conductivity substance in the burden. The resistance of the coke has to be high enough to ensure the proper functionality of the furnace. Used cokes for submerged arc furnace production are relatively small in size compared to e.g. blast furnace (BF) cokes. A common practice is to use screening residual coke, which is too small for the BF, in SAF. The goal of this study was to show differences in the electrical properties of screening residual cokes compared to coke formed in different parts of the coke battery, in dependence of particle size. The resistances of different cokes were measured and XRD measurements were performed to define the crystallographic structure of the selected cokes. The results indicate that small coke particles have higher overall resistance, which is due to their internal properties. This small weakly carbonized coke is formed in the middle of the coking battery and is subject to changes in varying coking practices. Continuous quality control of screening residual coke is needed to use it in the SAF. (orig.)

Stabilization of a nucleotide-binding domain of the cystic fibrosis transmembrane conductance regulator yields insight into disease-causing mutations.

Science.gov (United States)

Vernon, Robert M; Chong, P Andrew; Lin, Hong; Yang, Zhengrong; Zhou, Qingxian; Aleksandrov, Andrei A; Dawson, Jennifer E; Riordan, John R; Brouillette, Christie G; Thibodeau, Patrick H; Forman-Kay, Julie D

2017-08-25

Characterization of the second nucleotide-binding domain (NBD2) of the cystic fibrosis transmembrane conductance regulator (CFTR) has lagged behind research into the NBD1 domain, in part because NBD1 contains the F508del mutation, which is the dominant cause of cystic fibrosis. Research on NBD2 has also been hampered by the overall instability of the domain and the difficulty of producing reagents. Nonetheless, multiple disease-causing mutations reside in NBD2, and the domain is critical for CFTR function, because channel gating involves NBD1/NBD2 dimerization, and NBD2 contains the catalytically active ATPase site in CFTR. Recognizing the paucity of structural and biophysical data on NBD2, here we have defined a bioinformatics-based method for manually identifying stabilizing substitutions in NBD2, and we used an iterative process of screening single substitutions against thermal melting points to both produce minimally mutated stable constructs and individually characterize mutations. We present a range of stable constructs with minimal mutations to help inform further research on NBD2. We have used this stabilized background to study the effects of NBD2 mutations identified in cystic fibrosis (CF) patients, demonstrating that mutants such as N1303K and G1349D are characterized by lower stability, as shown previously for some NBD1 mutations, suggesting a potential role for NBD2 instability in the pathology of CF. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Estudo de mutações do gene CFTR e da concentração sérica da lectina ligante de manose (MBL) em crianças com fibrose cística identificadas pela triagem neonatal

OpenAIRE

Ribas, Danieli Isabel Romanovitch

2014-01-01

Orientador: Prof. Dr. Nelson Augusto Rosário Filho Co-orientadora: Profª. Drª. Lilian Pereira Ferrari Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Medicina Interna. Defesa : Curitiba, 19/12/2014 Inclui referências Resumo: A fibrose cística é uma doença hereditária autossômica recessiva, causada por mutações no gene CFTR (Cystic Fibrosis Transmembrane Conductance Regulator). Apresenta grande variação clínica, mesm...

Proinflammatory effect of sodium 4-phenylbutyrate in deltaF508-cystic fibrosis transmembrane conductance regulator lung epithelial cells: involvement of extracellular signal-regulated protein kinase 1/2 and c-Jun-NH2-terminal kinase signaling.

Science.gov (United States)

Roque, Telma; Boncoeur, Emilie; Saint-Criq, Vinciane; Bonvin, Elise; Clement, Annick; Tabary, Olivier; Jacquot, Jacky

2008-09-01

Sodium 4-phenylbutyrate (4-PBA) has attracted a great deal of attention in cystic fibrosis (CF) pathology due to its capacity to traffic DeltaF508-cystic fibrosis transmembrane conductance regulator (CFTR) to the cell membrane and restore CFTR chloride function at the plasma membrane of CF lung cells in vitro and in vivo. Using two different DeltaF508-CFTR lung epithelial cell lines (CFBE41o- and IB3-1 cells, characterized with DeltaF508-homozygous and heterozygous genotype, respectively) in vitro, 4-PBA induced an increase of proinflammatory cytokine interleukin (IL)-8 production in a concentration-dependent manner. This 4-PBA-induced IL-8 production was associated with a strong reduction of proteasome and nuclear factor-kappaB transcriptional activities in the two DeltaF508-CFTR lung cells either in a resting state or after tumor necrosis factor-alpha stimulation. In contrast, a strong increase of activator protein-1 transcriptional activity was observed. The inhibition of extracellular signal-regulated protein kinase 1/2 (ERK1/2) by 1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio] butadiene (U0126) and 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one (PD98059) and c-Jun-NH(2)-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) by anthra[1,9-cd] pyrazol-6 (2H)-one (SP600125), respectively, was associated with a reduction (2-3.5-fold) of IL-8 production in both DeltaF508-CFTR lung cell lines treated with 4-PBA. No significant change of IL-8 production was observed after an inhibition of p38 MAPK with 4-[4-(4-fluorophenyl)-5-(4-pyridinyl)-1H-imidazol-2-yl] phenol (SB202190). Therefore, we suggest that inhibition of both ERK1/2 and JNK signaling may be a means to strongly reduce 4-PBA-induced IL-8 production in combination with 4-PBA treatment to restore CFTR Cl(-) channel function in lung epithelial cells of patients with CF.

General anesthetic octanol and related compounds activate wild-type and delF508 cystic fibrosis chloride channels

OpenAIRE

Marcet, Brice; Becq, Frédéric; Norez, Caroline; Delmas, Patrick; Verrier, Bernard

2004-01-01

Cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel is defective during cystic fibrosis (CF). Activators of the CFTR Cl− channel may be useful for therapy of CF. Here, we demonstrate that a range of general anesthetics like normal-alkanols (n-alkanols) and related compounds can stimulate the Cl− channel activity of wild-type CFTR and delF508-CFTR mutant.The effects of n-alkanols like octanol on CFTR activity were measured by iodide (125I) efflux and patch-clamp techniques o...

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

OpenAIRE

Sánchez, Karen; De Mendonca,Elizabeth; Matute,Xiorama; Chaustre,Ismenia; Villalon,Marlene; Takiff,Howard

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 ...

cGMP inhibition of type 3 phosphodiesterase is the major mechanism by which C-type natriuretic peptide activates CFTR in the shark rectal gland

Science.gov (United States)

De Jonge, Hugo R.; Tilly, Ben C.; Hogema, Boris M.; Pfau, Daniel J.; Kelley, Catherine A.; Kelley, Megan H.; Melita, August M.; Morris, Montana T.; Viola, Ryan M.

2013-01-01

The in vitro perfused rectal gland of the dogfish shark (Squalus acanthias) and filter-grown monolayers of primary cultures of shark rectal gland (SRG) epithelial cells were used to analyze the signal transduction pathway by which C-type natriuretic peptide (CNP) stimulates chloride secretion. CNP binds to natriuretic receptors in the basolateral membrane, elevates cellular cGMP, and opens cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels in the apical membrane. CNP-provoked chloride secretion was completely inhibitable by the nonspecific protein kinase inhibitor staurosporine and the PKA inhibitor H89 but insensitive to H8, an inhibitor of type I and II isoforms of cGMP-dependent protein kinase (cGKI and cGKII). CNP-induced secretion could not be mimicked by nonhydrolyzable cGMP analogs added alone or in combination with the protein kinase C activator phorbolester, arguing against a role for cGK or for cGMP-induced PKC signaling. We failed to detect a dogfish ortholog of cGKII by molecular cloning and affinity chromatography. However, inhibitors of the cGMP-inhibitable isoform of phosphodiesterase (PDE3) including milrinone, amrinone, and cilostamide but not inhibitors of other PDE isoenzymes mimicked the effect of CNP on chloride secretion in perfused glands and monolayers. CNP raised cGMP and cAMP levels in the SRG epithelial cells. This rise in cAMP as well as the CNP and amrinone-provoked chloride secretion, but not the rise in cGMP, was almost completely blocked by the Gαi-coupled adenylyl cyclase inhibitor somatostatin, arguing against a role for cGMP cross-activation of PKA in CNP action. These data provide molecular, functional, and pharmacological evidence for a CNP/cGMP/PDE3/cAMP/PKA signaling cascade coupled to CFTR in the SRG. PMID:24259420

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

Directory of Open Access Journals (Sweden)

Estrella M Levy

2004-06-01

Full Text Available 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 G542X were screened in wives. In all cases, it was possible to reduce the risk of CF/CBAVD descendants in these couples because none of the mutation were found in the 36 samples. Eight patients (23% showed abnormal chloride values (> 60 mmol/l. A second group of 6 patients (18% had borderline values of sweat chloride (40-59 mmol/l. We defined another group with 6 patients (18%, with normal sweat chloride levels (30-39 mmo/l and a fourth group of 14 (41% patients with sweat chloride below 30 mmol/l. DF508, the most frequent CF mutation in the Argentine population, was found on 15 of the 72 chromosomes (21%, R117H mutation was detected on 2 of 62 chromosomes (3%. Only one R347P allele was found on 28 chromosomes analyzed (2%. On a sample of 27 patients, IVS8 analysis showed a frequency of 6/56 chromosomes (11% of 5T allele. Even though these findings present an improvement in the detection of mutations related to clinical correlations in Argentine CBAVD population, the search for other common and uncommon mutations should be continued.La ausencia bilateral congénita de vasos deferentes (CBAVD es una forma de infertilidad masculina en la que se han identificado mutaciones en el gen de la conductancia transmembrana de la fibrosis quística (CFTR. Hemos estudiado en pacientes argentinos diferentes mutaciones en el CFTR y la variante poli T del intron 8 (IVS8 y analizado los valores de test del sudor y las características clínicas relacionadas a la Fibrosis Qu

Measuring the residual stress of transparent conductive oxide films on PET by the double-beam shadow Moiré interferometer

Science.gov (United States)

Chen, Hsi-Chao; Huang, Kuo-Ting; Lo, Yen-Ming; Chiu, Hsuan-Yi; Chen, Guan-Jhen

2011-09-01

The purpose of this research was to construct a measurement system which can fast and accurately analyze the residual stress of the flexible electronics. The transparent conductive oxide (TCO) films, tin-doped indium oxide (ITO), were deposited by radio frequency (RF) magnetron sputtering using corresponding oxide targets on PET substrate. As we know that the shadow Moiré interferometry is a useable way to measure the large deformation. So we set up a double beam shadow Moiré interferometer to measure and analyze the residual stress of TCO films on PET. The feature was to develop a mathematical model and combine the image processing software. By the LabVIEW graphical software, we could measure the distance which is between the left and right fringe on the pattern to solve the curvature of deformed surface. Hence, the residual stress could calculate by the Stoney correction formula for the flexible electronics. By combining phase shifting method with shadow Moiré, the measurement resolution and accuracy have been greatly improved. We also had done the error analysis for the system whose relative error could be about 2%. Therefore, shadow Moiré interferometer is a non-destructive, fast, and simple system for the residual stress on TCO/PET films.

A European regulatory perspective on cystic fibrosis: current treatments, trends in drug development and translational challenges for CFTR modulators.

Science.gov (United States)

Ponzano, Stefano; Nigrelli, Giulia; Fregonese, Laura; Eichler, Irmgard; Bertozzi, Fabio; Bandiera, Tiziano; Galietta, Luis J V; Papaluca, Marisa

2018-06-30

In this article we analyse the current authorised treatments and trends in early drug development for cystic fibrosis (CF) in the European Union for the time period 2000-2016. The analysis indicates a significant improvement in the innovation and development of new potential medicines for CF, shifting from products that act on the symptoms of the disease towards new therapies targeting the cause of CF. However, within these new innovative medicines, results for CF transmembrane conductance regulator (CFTR) modulators indicate that one major challenge for turning a CF concept product into an actual medicine for the benefit of patients resides in the fact that, although pre-clinical models have shown good predictability for certain mutations, a good correlation to clinical end-points or biomarkers ( e.g. forced expiratory volume in 1 s and sweat chloride) for all mutations has not yet been achieved. In this respect, the use of alternative end-points and innovative nonclinical models could be helpful for the understanding of those translational discrepancies. Collaborative endeavours to promote further research and development in these areas as well as early dialogue with the regulatory bodies available at the European competent authorities are recommended. Copyright ©ERS 2018.

Breakthrough Therapies: Cystic Fibrosis (CF) Potentiators and Correctors

Science.gov (United States)

Solomon, George M.; Marshall, Susan G.; Ramsey, Bonnie W.; Rowe, Steven M.

2015-01-01

Cystic Fibrosis is caused by mutations in the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene resulting in abnormal protein function. Recent advances of targeted molecular therapies and high throughput screening have resulted in multiple drug therapies that target many important mutations in the CFTR protein. In this review, we provide the latest results and current progress of CFTR modulators for the treatment of cystic fibrosis, focusing on potentiators of CFTR channel gating and Phe508del processing correctors for the Phe508del CFTR mutation. Special emphasis is placed on the molecular basis underlying these new therapies and emerging results from the latest clinical trials. The future directions for augmenting the rescue of Phe508del with CFTR modulators is also emphasized. PMID:26097168

Residual radioactive contamination of the Maralinga range from nuclear weapons tests conducted in 1956 and 1957

International Nuclear Information System (INIS)

Cooper, M.B.; Duggleby, J.C.; Kotler, L.H.; Wise, K.N.

1978-12-01

Detailed geographical distributions and concentrations of long-lived radionuclides remaining from the major trials of nuclear weapons conducted at Maralinga in 1956 and 1957 are presented. It is shown that residual contamination due to fission products - mainly strontium-90, caesium-137 and europium-155 - are well below levels that could constitute a health hazard to occupants of the area. In the regions near the ground zeroes however, long-lived neutron activation products in soil - mainly cobalt-60 and europium-152 - are present in sufficient abundance to give rise to gamma-radiation dose-rates up to 2 milliroentgen per hour, which exceed maximum recommended dose-rates for continuous occupancy

Compounds that correct F508del-CFTR trafficking can also correct other protein trafficking diseases: an in vitro study using cell lines

OpenAIRE

Sampson Heidi M; Lam Hung; Chen Pei-Chun; Zhang Donglei; Mottillo Cristina; Mirza Myriam; Qasim Karim; Shrier Alvin; Shyng Show-Ling; Hanrahan John W; Thomas David Y

2013-01-01

Abstract Background Many genetic diseases are due to defects in protein trafficking where the mutant protein is recognized by the quality control systems, retained in the endoplasmic reticulum (ER), and degraded by the proteasome. In many cases, the mutant protein retains function if it can be trafficked to its proper cellular location. We have identified structurally diverse correctors that restore the trafficking and function of the most common mutation causing cystic fibrosis, F508del-CFTR...

Recipe for residual oil saturation determination

Energy Technology Data Exchange (ETDEWEB)

Guillory, A.J.; Kidwell, C.M.

1979-01-01

In 1978, Shell Oil Co., in conjunction with the US Department of Energy, conducted a residual oil saturation study in a deep, hot high-pressured Gulf Coast Reservoir. The work was conducted prior to initiation of CO/sub 2/ tertiary recovery pilot. Many problems had to be resolved prior to and during the residual oil saturation determination. The problems confronted are outlined such that the procedure can be used much like a cookbook in designing future studies in similar reservoirs. Primary discussion centers around planning and results of a log-inject-log operation used as a prime method to determine the residual oil saturation. Several independent methods were used to calculate the residual oil saturation in the subject well in an interval between 12,910 ft (3935 m) and 12,020 ft (3938 m). In general, these numbers were in good agreement and indicated a residual oil saturation between 22% and 24%. 10 references.

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.

Invariant TAD Boundaries Constrain Cell-Type-Specific Looping Interactions between Promoters and Distal Elements around the CFTR Locus.

Science.gov (United States)

Smith, Emily M; Lajoie, Bryan R; Jain, Gaurav; Dekker, Job

2016-01-07

Three-dimensional genome structure plays an important role in gene regulation. Globally, chromosomes are organized into active and inactive compartments while, at the gene level, looping interactions connect promoters to regulatory elements. Topologically associating domains (TADs), typically several hundred kilobases in size, form an intermediate level of organization. Major questions include how TADs are formed and how they are related to looping interactions between genes and regulatory elements. Here we performed a focused 5C analysis of a 2.8 Mb chromosome 7 region surrounding CFTR in a panel of cell types. We find that the same TAD boundaries are present in all cell types, indicating that TADs represent a universal chromosome architecture. Furthermore, we find that these TAD boundaries are present irrespective of the expression and looping of genes located between them. In contrast, looping interactions between promoters and regulatory elements are cell-type specific and occur mostly within TADs. This is exemplified by the CFTR promoter that in different cell types interacts with distinct sets of distal cell-type-specific regulatory elements that are all located within the same TAD. Finally, we find that long-range associations between loci located in different TADs are also detected, but these display much lower interaction frequencies than looping interactions within TADs. Interestingly, interactions between TADs are also highly cell-type-specific and often involve loci clustered around TAD boundaries. These data point to key roles of invariant TAD boundaries in constraining as well as mediating cell-type-specific long-range interactions and gene regulation. Copyright © 2016 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

General anesthetic octanol and related compounds activate wild-type and delF508 cystic fibrosis chloride channels.

Science.gov (United States)

Marcet, Brice; Becq, Frédéric; Norez, Caroline; Delmas, Patrick; Verrier, Bernard

2004-03-01

1. Cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel is defective during cystic fibrosis (CF). Activators of the CFTR Cl(-) channel may be useful for therapy of CF. Here, we demonstrate that a range of general anesthetics like normal-alkanols (n-alkanols) and related compounds can stimulate the Cl(-) channel activity of wild-type CFTR and delF508-CFTR mutant. 2. The effects of n-alkanols like octanol on CFTR activity were measured by iodide ((125)I) efflux and patch-clamp techniques on three distinct cellular models: (1). CFTR-expressing Chinese hamster ovary cells, (2). human airway Calu-3 epithelial cells and (3). human airway JME/CF15 epithelial cells which express the delF508-CFTR mutant. 3. Our data show for the first time that n-alkanols activate both wild-type CFTR and delF508-CFTR mutant. Octanol stimulated (125)I efflux in a dose-dependent manner in CFTR-expressing cells (wild-type and delF508) but not in cell lines lacking CFTR. (125)I efflux and Cl(-) currents induced by octanol were blocked by glibenclamide but insensitive to 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, as expected for a CFTR Cl(-) current. 4. CFTR activation by octanol was neither due to cell-to-cell uncoupling properties of octanol nor to an intracellular cAMP increase. CFTR activation by octanol requires phosphorylation by protein kinase-A (PKA) since it was prevented by H-89, a PKA inhibitor. 5. n-Alkanols chain length was an important determinant for channel activation, with rank order of potencies: 1-heptanoloctanoloctanol<1-decanol. Our findings may be of valuable interest for developing novel therapeutic strategies for CF.

Novel short chain fatty acids restore chloride secretion in cystic fibrosis

International Nuclear Information System (INIS)

Nguyen, Toan D.; Kim, Ug-Sung; Perrine, Susan P.

2006-01-01

Phenylalanine deletion at position 508 of the cystic fibrosis transmembrane conductance regulator (ΔF508-CFTR), the most common mutation in cystic fibrosis (CF), causes a misfolded protein exhibiting partial chloride conductance and impaired trafficking to the plasma membrane. 4-Phenylbutyrate corrects defective ΔF508-CFTR trafficking in vitro, but is not clinically efficacious. From a panel of short chain fatty acid derivatives, we showed that 2,2-dimethyl-butyrate (ST20) and α-methylhydrocinnamic acid (ST7), exhibiting high oral bioavailability and sustained plasma levels, correct the ΔF508-CFTR defect. Pre-incubation (≥6 h) of CF IB3-1 airway cells with ≥1 mM ST7 or ST20 restored the ability of 100 μM forskolin to stimulate an 125 I - efflux. This efflux was fully inhibited by NPPB, DPC, or glibenclamide, suggesting mediation through CFTR. Partial inhibition by DIDS suggests possible contribution from an additional Cl - channel regulated by CFTR. Thus, ST7 and ST20 offer treatment potential for CF caused by the ΔF508 mutation

Clinical expression of patients with the D1152H CFTR mutation.

Science.gov (United States)

Terlizzi, Vito; Carnovale, Vincenzo; Castaldo, Giuseppe; Castellani, Carlo; Cirilli, Natalia; Colombo, Carla; Corti, Fabiola; Cresta, Federico; D'Adda, Alice; Lucarelli, Marco; Lucidi, Vincenzina; Macchiaroli, Annamaria; Madarena, Elisa; Padoan, Rita; Quattrucci, Serena; Salvatore, Donatello; Zarrilli, Federica; Raia, Valeria

2015-07-01

Discordant results were reported on the clinical expression of subjects bearing the D1152H CFTR mutation, and also for the small number of cases reported so far. A retrospective review of clinical, genetic and biochemical data was performed from individuals homozygous or compound heterozygous for the D1152H mutation followed in 12 Italian cystic fibrosis (CF) centers. 89 subjects carrying at least D1152H on one allele were identified. 7 homozygous patients had very mild clinical expression. Over half of the 74 subjects compound heterozygous for D1152H and a I-II-III class mutation had borderline or pathological sweat test and respiratory or gastrointestinal symptoms; one third had pulmonary bacteria colonization and 10/74 cases had complications (i.e. diabetes, allergic bronchopulmonary aspergillosis, and hemoptysis). However, their clinical expression was less severe as compared to a group of CF patients homozygous for the F508del mutation. Finally, 8 subjects compound heterozygous for D1152H and a IV-V class mutation showed very mild disease. The natural history of subjects bearing the D1152H mutation is widely heterogeneous and is influenced by the mutation in trans. Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Nutritional Status Improved in Cystic Fibrosis Patients with the G551D Mutation After Treatment with Ivacaftor

NARCIS (Netherlands)

Borowitz, Drucy; Lubarsky, Barry; Wilschanski, Michael; Munck, Anne; Gelfond, Daniel; Bodewes, Frank; Schwarzenberg, Sarah Jane

The cystic fibrosis (CF) transmembrane conductance regulator (CFTR) gating mutation G551D prevents sufficient ion transport due to reduced channel-open probability. Ivacaftor, an oral CFTR potentiator, increases the channel-open probability. To further analyze improvements in weight and body mass

Reactivity of Athabasca residue and of its SARA fractions during residue hydroconversion

Energy Technology Data Exchange (ETDEWEB)

Verstraete, J.; Danial-Fortain, P.; Gauthier, T.; Merdrignac, I. [IFP-Lyon, Vermaison (France); Budzinski, H. [Bordeaux Univ. (France). ISM-LPTC, UMR CNRS

2009-07-01

Residue conversion processes are becoming increasingly important because of the declining market for residual fuel oil and a greater demand for middle distillates. Ebullated-bed hydroconversion is a commercially proven technology for converting heavy feedstocks with high amounts of impurities. The process enables the conversion of atmospheric or vacuum residues at temperatures up to 440 degrees C, and at liquid hourly space velocity (LHSV) conditions in the range of 0.15 to 0.5 per hour. A 540 degrees C conversion of up to 80 weight per cent can be achieved under these conditions. This paper reported on a research study conducted at IFP Lyon in which the residue hydroconversion in a large-scale ebullated bed bench unit was investigated to determine the impact of operating conditions and feed properties on yield and product qualities. Hydrogen was added to the feed in the bench units to keep a high hydrogen partial pressure and favour the catalytic hydroconversion reactions. In a typical test, the reactor was fed with 50 g of feedstock and 0.45 g of crushed equilibrium industrial NiMo catalyst, pressurized hydrogen and quickly heated at the reaction temperature. This paper also discussed the conversion of Athabasca bitumen residue in the large-scale pilot plant and also in the small scale batch reactor. The effect of operating temperature and space velocity was examined. The reactivity of the saturates, aromatics, resins and asphaltenes (SARA) fractions of the bitumen was studied separately in order to better understand the conversion mechanisms and reactivities. The Athabasca bitumen feed and SARA fractions were also analyzed in terms of standard petroleum analysis, SARA fractionation, elemental analysis, size exclusion chromatography (SEC) and 13C NMR. Hydroconversion experiments were conducted in the batch unit at different reaction temperatures and reaction times. A comparison of small-scale batch results with those obtained with the continuous large-scale bench

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.

Does Bt Corn Really Produce Tougher Residues

Science.gov (United States)

Bt corn hybrids produce insecticidal proteins that are derived from a bacterium, Bacillus thuringiensis. There have been concerns that Bt corn hybrids produce residues that are relatively resistant to decomposition. We conducted four experiments that examined the decomposition of corn residues und...

Effect of heat treatment temperature on binder thermal conductivities

International Nuclear Information System (INIS)

Wagner, P.

1975-12-01

The effect of heat treatment on the thermal conductivities of a pitch and a polyfurfuryl alcohol binder residue was investigated. Graphites specially prepared with these two binders were used for the experiments. Measured thermal conductivities were treated in terms of a two-component system, and the binder thermal conductivities were calculated. Both binder residues showed increased thermal conductivity with increased heat treatment temperature

Evaluation of Crops Sensitivity to Atrazine Soil Residual

Directory of Open Access Journals (Sweden)

E Izadi

2012-02-01

Full Text Available Abstract In order to study the sensitivity of 9 crops to atrazine soil residual, two separate experiments were conducted in field and greenhouse conditions. First experiment was conducted in a field with treated soil by atrazine based on split plot and the results evaluated in greenhouse conditions. Treatments in the field experiment included two organic manure application rates (0 and 50 t/ha as main plots and 2 atrazine application rates (2 and 4 kg/ha atrazine a.i. as sob plots. After corn harvesting soil was sampled at 0-15 cm surface layer in each plots in 15 points, after mixing the samples. Wheat, barley, sugar beet, pea, lens and colza planted in pots at greenhouse. Second experiment conducted in greenhouse conditions for evaluation of atrazine soil residual in completely randomized design. Treatments included atrazine soil residual concentrations (0, 0.2, 0.5, 1, 5, 10 and 15 mg/kg soil and crops included wheat, barley, sugar beet, pea, lens, rape, bean and tomato. Results showed that atrazine residue had no effect on crops growth in field experiment treated with atrazine. It seems that atrazine residue in filed soil is lower that its damage threshold for crops or maybe for its fast removal in field than in control conditions. But in bioassay experiment (greenhouse experiment crops response to atrazine residues were different. Results showed that onion and pea were most susceptible ant tolerant crops between studied species and based of ED50 parameter the other crops tolerance to total residue ranked as: pea< bean< lentil< sugar beet< tomato< barley< wheat< rape< onion. Keywords: Atrazine residue, Pea, Bean, Lentil, Sugar beet, Barley, Wheat, Rape, Tomato

Strategies for the etiological therapy of cystic fibrosis.

Science.gov (United States)

Maiuri, Luigi; Raia, Valeria; Kroemer, Guido

2017-11-01

Etiological therapies aim at repairing the underlying cause of cystic fibrosis (CF), which is the functional defect of the cystic fibrosis transmembrane conductance regulator (CFTR) protein owing to mutations in the CFTR gene. Among these, the F508del CFTR mutation accounts for more than two thirds of CF cases worldwide. Two somehow antinomic schools of thought conceive CFTR repair in a different manner. According to one vision, drugs should directly target the mutated CFTR protein to increase its plasma membrane expression (correctors) or improve its ion transport function (potentiators). An alternative strategy consists in modulating the cellular environment and proteostasis networks in which the mutated CFTR protein is synthesized, traffics to its final destination, the plasma membrane, and is turned over. We will analyze distinctive advantages and drawbacks of these strategies in terms of their scientific and clinical dimensions, and we will propose a global strategy for CF research and development based on a reconciliatory approach. Moreover, we will discuss the utility of preclinical biomarkers that may guide the personalized, patient-specific implementation of CF therapies.

Conductive polymeric compositions for lithium batteries

Science.gov (United States)

Angell, Charles A [Mesa, AZ; Xu, Wu [Tempe, AZ

2009-03-17

Novel chain polymers comprising weakly basic anionic moieties chemically bound into a polyether backbone at controllable anionic separations are presented. Preferred polymers comprise orthoborate anions capped with dibasic acid residues, preferably oxalato or malonato acid residues. The conductivity of these polymers is found to be high relative to that of most conventional salt-in-polymer electrolytes. The conductivity at high temperatures and wide electrochemical window make these materials especially suitable as electrolytes for rechargeable lithium batteries.

Repeated nebulisation of non-viral CFTR gene therapy in patients with cystic fibrosis: a randomised, double-blind, placebo-controlled, phase 2b trial.

Science.gov (United States)

Alton, Eric W F W; Armstrong, David K; Ashby, Deborah; Bayfield, Katie J; Bilton, Diana; Bloomfield, Emily V; Boyd, A Christopher; Brand, June; Buchan, Ruaridh; Calcedo, Roberto; Carvelli, Paula; Chan, Mario; Cheng, Seng H; Collie, D David S; Cunningham, Steve; Davidson, Heather E; Davies, Gwyneth; Davies, Jane C; Davies, Lee A; Dewar, Maria H; Doherty, Ann; Donovan, Jackie; Dwyer, Natalie S; Elgmati, Hala I; Featherstone, Rosanna F; Gavino, Jemyr; Gea-Sorli, Sabrina; Geddes, Duncan M; Gibson, James S R; Gill, Deborah R; Greening, Andrew P; Griesenbach, Uta; Hansell, David M; Harman, Katharine; Higgins, Tracy E; Hodges, Samantha L; Hyde, Stephen C; Hyndman, Laura; Innes, J Alastair; Jacob, Joseph; Jones, Nancy; Keogh, Brian F; Limberis, Maria P; Lloyd-Evans, Paul; Maclean, Alan W; Manvell, Michelle C; McCormick, Dominique; McGovern, Michael; McLachlan, Gerry; Meng, Cuixiang; Montero, M Angeles; Milligan, Hazel; Moyce, Laura J; Murray, Gordon D; Nicholson, Andrew G; Osadolor, Tina; Parra-Leiton, Javier; Porteous, David J; Pringle, Ian A; Punch, Emma K; Pytel, Kamila M; Quittner, Alexandra L; Rivellini, Gina; Saunders, Clare J; Scheule, Ronald K; Sheard, Sarah; Simmonds, Nicholas J; Smith, Keith; Smith, Stephen N; Soussi, Najwa; Soussi, Samia; Spearing, Emma J; Stevenson, Barbara J; Sumner-Jones, Stephanie G; Turkkila, Minna; Ureta, Rosa P; Waller, Michael D; Wasowicz, Marguerite Y; Wilson, James M; Wolstenholme-Hogg, Paul

2015-09-01

Lung delivery of plasmid DNA encoding the CFTR gene complexed with a cationic liposome is a potential treatment option for patients with cystic fibrosis. We aimed to assess the efficacy of non-viral CFTR gene therapy in patients with cystic fibrosis. We did this randomised, double-blind, placebo-controlled, phase 2b trial in two cystic fibrosis centres with patients recruited from 18 sites in the UK. Patients (aged ≥12 years) with a forced expiratory volume in 1 s (FEV1) of 50-90% predicted and any combination of CFTR mutations, were randomly assigned, via a computer-based randomisation system, to receive 5 mL of either nebulised pGM169/GL67A gene-liposome complex or 0.9% saline (placebo) every 28 days (plus or minus 5 days) for 1 year. Randomisation was stratified by % predicted FEV1 (<70 vs ≥70%), age (<18 vs ≥18 years), inclusion in the mechanistic substudy, and dosing site (London or Edinburgh). Participants and investigators were masked to treatment allocation. The primary endpoint was the relative change in % predicted FEV1. The primary analysis was per protocol. This trial is registered with ClinicalTrials.gov, number NCT01621867. Between June 12, 2012, and June 24, 2013, we randomly assigned 140 patients to receive placebo (n=62) or pGM169/GL67A (n=78), of whom 116 (83%) patients comprised the per-protocol population. We noted a significant, albeit modest, treatment effect in the pGM169/GL67A group versus placebo at 12 months' follow-up (3.7%, 95% CI 0.1-7.3; p=0.046). This outcome was associated with a stabilisation of lung function in the pGM169/GL67A group compared with a decline in the placebo group. We recorded no significant difference in treatment-attributable adverse events between groups. Monthly application of the pGM169/GL67A gene therapy formulation was associated with a significant, albeit modest, benefit in FEV1 compared with placebo at 1 year, indicating a stabilisation of lung function in the treatment group. Further improvements in

Cystic fibrosis: a mucosal immunodeficiency syndrome

Science.gov (United States)

Cohen, Taylor Sitarik; Prince, Alice

2013-01-01

Cystic fibrosis transmembrane conductance regulator (CFTR) functions as a channel that regulates the transport of ions and the movement of water across the epithelial barrier. Mutations in CFTR, which form the basis for the clinical manifestations of cystic fibrosis, affect the epithelial innate immune function in the lung, resulting in exaggerated and ineffective airway inflammation that fails to eradicate pulmonary pathogens. Compounding the effects of excessive neutrophil recruitment, the mutant CFTR channel does not transport antioxidants to counteract neutrophil-associated oxidative stress. Whereas mutant CFTR expression in leukocytes outside of the lung does not markedly impair their function, the expected regulation of inflammation in the airways is clearly deficient in cystic fibrosis. The resulting bacterial infections, which are caused by organisms that have substantial genetic and metabolic flexibility, can resist multiple classes of antibiotics and evade phagocytic clearance. The development of animal models that approximate the human pulmonary phenotypes—airway inflammation and spontaneous infection—may provide the much-needed tools to establish how CFTR regulates mucosal immunity and to test directly the effect of pharmacologic potentiation and correction of mutant CFTR function on bacterial clearance. PMID:22481418

Integration of conducting polymer network in non-conductive polymer substrates

DEFF Research Database (Denmark)

Hansen, Thomas Steen; West, Keld; Hassager, Ole

2006-01-01

Anew method for integration ofconjugated, inherently conducting polymers into non-conductive polymer substrates has been developed. Alayer of the conducting polymer is polymerised by chemical oxidation, e.g. using Fe(ID) p-toluene sulfonate (ferri tosylate) followed by washing with a solvent which...... simultaneously removes residual and spent oxidant and at the same time dissolves the top layer of the polymer substrate. This results in an integration of the conducting polymer into the surface layers of the polymer substrate. Several combinations of conducting polymers and substrates have been tested...... absorption during sequential reactive ion etching has allowed for analysis of the PEDOT distribution within the surface layer of thePMMA substrate. The surface resistance ofthe conducting polymer layer remains low while the surface layer at the same time adapts some of the mechanical properties...

Modelling of the Residual Stress State in a new Type of Residual Stress Specimen

DEFF Research Database (Denmark)

Jakobsen, Johnny; Andreasen, Jens Henrik

2014-01-01

forms the experimental case which is analysed. A FE model of the specimen is used for analysing the curing history and the residual stress build up. The model is validated against experimental strain data which are recorded by a Fibre Brag Grating sensor and good agreement has been achieved.......The paper presents a study on a new type residual stress specimen which is proposed as a simple way to conduct experimental validation for model predictions. A specimen comprising of a steel plate with circular hole embedded into a stack of CSM glass fibre and further infused with an epoxy resin...

Residual nilpotence and residual solubility of groups

International Nuclear Information System (INIS)

Mikhailov, R V

2005-01-01

The properties of the residual nilpotence and the residual solubility of groups are studied. The main objects under investigation are the class of residually nilpotent groups such that each central extension of these groups is also residually nilpotent and the class of residually soluble groups such that each Abelian extension of these groups is residually soluble. Various examples of groups not belonging to these classes are constructed by homological methods and methods of the theory of modules over group rings. Several applications of the theory under consideration are presented and problems concerning the residual nilpotence of one-relator groups are considered.

Polystyrene nanoparticles activate ion transport in human airway epithelial cells

Directory of Open Access Journals (Sweden)

McCarthy J

2011-06-01

Full Text Available J McCarthy1, X Gong2, D Nahirney2, M Duszyk2, MW Radomski11School of Pharmacy and Pharmaceutical Sciences, Panoz Institute, Trinity College Dublin, Dublin, Ireland; 2Department of Physiology, University of Alberta, Edmonton, Alberta, CanadaBackground: Over the last decade, nanotechnology has provided researchers with new nanometer materials, such as nanoparticles, which have the potential to provide new therapies for many lung diseases. In this study, we investigated the acute effects of polystyrene nanoparticles on epithelial ion channel function.Methods: Human submucosal Calu-3 cells that express cystic fibrosis transmembrane conductance regulator (CFTR and baby hamster kidney cells engineered to express the wild-type CFTR gene were used to investigate the actions of negatively charged 20 nm polystyrene nanoparticles on short-circuit current in Calu-3 cells by Ussing chamber and single CFTR Cl- channels alone and in the presence of known CFTR channel activators by using baby hamster kidney cell patches.Results: Polystyrene nanoparticles caused sustained, repeatable, and concentration-dependent increases in short-circuit current. In turn, these short-circuit current responses were found to be biphasic in nature, ie, an initial peak followed by a plateau. EC50 values for peak and plateau short-circuit current responses were 1457 and 315.5 ng/mL, respectively. Short-circuit current was inhibited by diphenylamine-2-carboxylate, a CFTR Cl- channel blocker. Polystyrene nanoparticles activated basolateral K+ channels and affected Cl- and HCO3- secretion. The mechanism of short-circuit current activation by polystyrene nanoparticles was found to be largely dependent on calcium-dependent and cyclic nucleotide-dependent phosphorylation of CFTR Cl- channels. Recordings from isolated inside-out patches using baby hamster kidney cells confirmed the direct activation of CFTR Cl- channels by the nanoparticles.Conclusion: This is the first study to identify

Mutations of the cystic fibrosis gene, but not cationic trypsinogen gene, are associated with recurrent or chronic idiopathic pancreatitis.

Science.gov (United States)

Ockenga, J; Stuhrmann, M; Ballmann, M; Teich, N; Keim, V; Dörk, T; Manns, M P

2000-08-01

We investigated whether mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene and cationic trypsinogen gene are associated with recurrent acute, or chronic idiopathic pancreatitis. Twenty patients with idiopathic pancreatitis (11 women, nine men; mean age, 30 yr) were studied for the presence of a CFTR mutation by screening the genomic DNA for more than 30 mutations and variants in the CFTR gene. Selected mutations of the cationic trypsinogen gene were screened by Afl III restriction digestion or by a mutation-specific polymerase chain reaction (PCR). In each patient exons 1, 2, and 3 of the cationic trypsinogen gene were sequenced. Patients with a CFTR mutation underwent evaluation of further functional electrophysiological test (intestinal current measurement). No mutation of the cationic trypsinogen gene was detected. A CFTR mutation was detected in 6/20 (30.0%) patients. Three patients (15.0%) had a cystic fibrosis (CF) mutation on one chromosome (deltaF508, I336K, Y1092X), which is known to cause phenotypical severe cystic fibrosis. One patient was heterozygous for the 5T allele. In addition, two possibly predisposing CFTR variants (R75Q, 1716G-->A) were detected on four patients, one of these being a compound heterozygous for the missense mutation I336K and R75Q. No other family member (maternal I336K; paternal R75Q; sister I1336K) developed pancreatitis. An intestinal current measurement in rectum samples of patients with a CFTR mutation revealed no CF-typical constellations. CFTR mutations are associated with recurrent acute, or chronic idiopathic pancreatitis, whereas mutations of the cationic trypsinogen mutation do not appear to be a frequent pathogenetic factor.

[Genetic counseling in cystic fibrosis].

Science.gov (United States)

Julia, S; Bieth, E

2000-08-01

Genetic counseling is an important part of health care in patients with cystic fibrosis or respiratory diseases associated with the CFTR (cystic fibrosis transmembrane conductance regulator) gene, including certain types of allergic bronchopulmonary aspergilloses or bronchial diseases (diffuse bronchiectasia). The basic goal is to provide patients with information on the transmission of cystic fibrosis and to asses the risk of recurrence. This risk is determined from molecular biology analyses examining the CFTR gene. Genotyping is the only means of screening for the heterozygous state, frequent in the French population (about 1/30). Because of the large number of mutated alleles not covered entirely by the genetic tests, there remains a question of probability expressed as a residual risk of a heterozygous state. A prenatal genotype diagnosis should be proposed to heterozygous couples who have a 25% risk of having a diseased child. Technically, this is almost always possible and the results are highly reliable. Nevertheless, there remains the risks related to sample taking and the ethical issue about which the patients must be informed. Management of these at risk couples who desire a child must be based on a multidisciplinary approach, particularly important when one of the parents has overt cystic fibrosis.

Crop residue decomposition, residual soil organic matter and nitrogen mineralization in arable soils with contrasting textures

NARCIS (Netherlands)

Matus, F.J.

1994-01-01

To evaluate the significance of cropping, soil texture and soil structure for the decomposition of ¹⁴C- and ¹⁵N-labelled crop residues, a study was conducted in a sand and a

Round window stimulation for conductive and mixed hearing loss.

Science.gov (United States)

Dillon, Margaret T; Tubbs, Rhonda S; Adunka, Marcia C; King, English R; Hillman, Todd A; Adunka, Oliver F; Chen, Douglas A; Buchman, Craig A

2014-10-01

Assess surgical complications, postoperative residual hearing, and speech perception outcomes of placement of a middle ear implant on the round window in conductive and mixed hearing loss cases. Single-subject, repeated-measures design where each subject served as his or her own control. Tertiary referral medical systems. Eighteen subjects with either conductive or mixed hearing loss who could not benefit from conventional amplification were enrolled in a clinical trial investigating vibratory stimulation of the round window. The floating mass transducer (FMT) was positioned in the round window niche. Unaided residual hearing, and aided sound field thresholds and speech perception abilities were evaluated preoperatively, and at 1, 3, 6, and 10 months post-activation of the external speech processor. Six subjects experienced complications that either required further medical management or resolved on their own. There was no difference in residual bone conduction thresholds or unaided word discrimination over time. All subjects experienced a significant improvement in aided speech perception abilities as compared to preoperative performance. Subjects with conductive and mixed hearing loss with placement of the FMT in the round window niche experienced improved sound field thresholds and speech perception, without compromising residual hearing thresholds. Vibratory stimulation of the round window via a middle ear implant may be an appropriate treatment option for patients with conductive and mixed hearing loss. Additional research is needed on the preferred placement of the FMT, improvement of functional gain, and methods to limit postoperative complications and need for revision surgery.

Thermal Aging Effects on Residual Stress and Residual Strain Distribution on Heat Affected Zone of Alloy 600 in Dissimilar Metal Weld

Energy Technology Data Exchange (ETDEWEB)

Ham, Junhyuk; Choi, Kyoung Joon; Kim, Ji Hyun [UNIST, Ulsan (Korea, Republic of)

2016-10-15

Dissimilar metal weld (DMW), consisting of Alloy 600, Alloy 182, and A508 Gr.3, has been widely used as a joining material of the reactor pressure vessel penetration nozzle and the steam generator tubing for pressurized water reactors (PWR) because of its good mechanical strength, thermal conductivity, and corrosion resistance. Residual tensile stress is mainly nominated as a cause of SCC in light water reactors by IAEA report. So, to relax the residual stress, post-weld heat treatment is required after manufacturing process such as welding. However, thermal treatment has a great effect on the microstructure and the chromium depletion profile on Alloy 600, so called sensitization. By this reason, HAZ on Alloy 600 is critical to crack. According to G.A. Young et al., Crack growth rates (CGR) in the Alloy 600 HAZ were about 30 times faster than those in the Alloy 600 base metal tested under the same conditions. And according to Z.P. Lu et al., CGR in the Alloy 600 HAZ can be more than 20 times higher than that in its base metal. There are some methods to measure the exact value of residual stress on the material surface. The most common way is X-ray diffraction method (XRD). The principle of XRD is based on lattice strains and depends on the changes in the spacing of the atomic planes in material. And there is a computer simulation method to estimate residual stress distribution which is called ANSYS. This study was conducted to investigate how thermal aging affects residual stress and residual strain distribution of Alloy 600 HAZ. Following conclusions can be drawn from this study. According to preceding researches and this study, both the relaxation of residual stress and the change of residual strain follow as similar way, spreading out from concentrated region. The result of Vickers micro-hardness tester shows that tensile residual stresses are distributed broadly on the material aged by 15 years. Therefore, HT400{sub Y}15 material is weakest state for PWSCC. The

Coking of residue hydroprocessing catalysts

Energy Technology Data Exchange (ETDEWEB)

Gray, M.R.; Zhao, Y.X. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical Engineering; McKnight, C.A. [Syncrude Canada Ltd., Edmonton, AB (Canada); Komar, D.A.; Carruthers, J.D. [Cytec Industries Inc., Stamford, CT (United States)

1997-11-01

One of the major causes of deactivation of Ni/Mo and Co/Mo sulfide catalysts for hydroprocessing of heavy petroleum and bitumen fractions is coke deposition. The composition and amount of coke deposited on residue hydroprocessing catalysts depends on the composition of the liquid phase of the reactor. In the Athabasca bitumen, the high molecular weight components encourage coke deposition at temperatures of 430 to 440 degrees C and at pressures of 10 to 20 MPa hydrogen pressure. A study was conducted to determine which components in the heavy residual oil fraction were responsible for coking of catalysts. Seven samples of Athabasca vacuum residue were prepared by supercritical fluid extraction with pentane before being placed in the reactor. Carbon content and hydrodesulfurization activity was measured. It was concluded that the deposition of coke depended on the presence of asphaltenes and not on other compositional variables such as content of nitrogen, aromatic carbon or vanadium.

Disposal of Rocky Flats residues as waste

International Nuclear Information System (INIS)

Dustin, D.F.; Sendelweck, V.S.

1993-01-01

Work is underway at the Rocky Flats Plant to evaluate alternatives for the removal of a large inventory of plutonium-contaminated residues from the plant. One alternative under consideration is to package the residues as transuranic wastes for ultimate shipment to the Waste Isolation Pilot Plant. Current waste acceptance criteria and transportation regulations require that approximately 1000 cubic yards of residues be repackaged to produce over 20,000 cubic yards of WIPP certified waste. The major regulatory drivers leading to this increase in waste volume are the fissile gram equivalent, surface radiation dose rate, and thermal power limits. In the interest of waste minimization, analyses have been conducted to determine, for each residue type, the controlling criterion leading to the volume increase, the impact of relaxing that criterion on subsequent waste volume, and the means by which rules changes may be implemented. The results of this study have identified the most appropriate changes to be proposed in regulatory requirements in order to minimize the costs of disposing of Rocky Flats residues as transuranic wastes

Quadratic residues and non-residues selected topics

CERN Document Server

Wright, Steve

2016-01-01

This book offers an account of the classical theory of quadratic residues and non-residues with the goal of using that theory as a lens through which to view the development of some of the fundamental methods employed in modern elementary, algebraic, and analytic number theory. The first three chapters present some basic facts and the history of quadratic residues and non-residues and discuss various proofs of the Law of Quadratic Reciprosity in depth, with an emphasis on the six proofs that Gauss published. The remaining seven chapters explore some interesting applications of the Law of Quadratic Reciprocity, prove some results concerning the distribution and arithmetic structure of quadratic residues and non-residues, provide a detailed proof of Dirichlet’s Class-Number Formula, and discuss the question of whether quadratic residues are randomly distributed. The text is a valuable resource for graduate and advanced undergraduate students as well as for mathematicians interested in number theory.

Chloroxyanion residues in cantaloupe and tomatoes after chlorine dioxide gas sanitation

Science.gov (United States)

Chlorine dioxide gas is effective at cleansing fruits and vegetables of bacterial pathogens and(or) rot organisms, but few data are available on chemical residues remaining subsequent to chlorine gas treatment. Therefore, studies were conducted to quantify chlorate and perchlorate residues after tom...

Evaluation of heavy metals in hazardous automobile shredder residue thermal residue and immobilization with novel nano-size calcium dispersed reagent.

Science.gov (United States)

Lee, Chi-Hyeon; Truc, Nguyen Thi Thanh; Lee, Byeong-Kyu; Mitoma, Yoshiharu; Mallampati, Srinivasa Reddy

2015-10-15

This study was conducted to synthesize and apply a nano-size calcium dispersed reagent as an immobilization material for heavy metal-contaminated automobile shredder residues (ASR) dust/thermal residues in dry condition. Simple mixing with a nanometallic Ca/CaO/PO4 dispersion mixture immobilized 95-100% of heavy metals in ASR dust/thermal residues (including bottom ash, cavity ash, boiler and bag filter ash). The quantity of heavy metals leached from thermal residues after treatment by nanometallic Ca/CaO/PO4 was lower than the Korean standard regulatory limit for hazardous waste landfills. The morphology and elemental composition of the nanometallic Ca/CaO-treated ASR residue were characterized by field emission scanning election microscopy combined with electron dispersive spectroscopy (FE-SEM/EDS). The results indicated that the amounts of heavy metals detectable on the ASR thermal residue surface decreased and the Ca/PO4 mass percent increased. X-ray diffraction (XRD) pattern analysis indicated that the main fraction of enclosed/bound materials on ASR residue included Ca/PO4- associated crystalline complexes, and that immobile Ca/PO4 salts remarkably inhibited the desorption of heavy metals from ASR residues. These results support the potential use of nanometallic Ca/CaO/PO4 as a simple, suitable and highly efficient material for the gentle immobilization of heavy metals in hazardous ASR thermal residue in dry condition. Copyright © 2015 Elsevier B.V. All rights reserved.

Estimation of residual life of boiler tubes using steamside oxide scale thickness

International Nuclear Information System (INIS)

Vikrant, K.S.N.; Ramareddy, G.V.; Pavan, A.H.V.; Singh, Kulvir

2013-01-01

In thermal power plants, remaining-life-estimation of boiler tubes is required at regular intervals for a safer and a better functionality of boilers. In this paper, a new method is proposed for the residual life estimation of service exposed boiler tubes using Non-Destructive Ultrasonic Oxide scale thickness measurements, average metal temperature and creep master curve. While steady state conduction heat transfer equations are solved to calculate the average metal temperature, creep master curve is generated from short term stress rupture data of rupture life less than 5000 h on a virgin material. In the present study, the residual life of T22 (2.25Cr-1Mo) service exposed Platen Superheater tube is estimated using two master creep curves, i.e. Larson-Miller Parametric (LMP) method of standard ASME T22 creep data and Wilshire approach of short term stress rupture data of T22. As the residual life is calculated from fundamental conduction heat transfer theory and creep rupture data, the proposed method can be applied for different grades of boiler materials. -- Highlights: ► Residual life is calculated from non-destructive oxide scale thickness, creep master curve and average metal temperature. ► A new method is proposed for calculating residual life using above parameters and from conduction heat transfer principles. ► The method can be applied to different boiler grades for estimating residual life and hence the method is generic

Evaluation and optimization of nutritional and environmental impact of biogas residues

International Nuclear Information System (INIS)

Lichti, Fabian Heribert

2013-01-01

On the basis of the dynamic growth of biogas plants in Germany the fertilization with biogas residues has obtained an important role for recirculation of plant nutrients, particularly with regard to nitrogen. In this work the effect of N nutrition with biogas residues was assessed in a 3-year on-field trial conducted at four sites throughout Bavaria. The fertilizing effects were tested by varying rate and time of biogas residues application, using different application techniques and the addition of nitrification inhibitors on several crops. The biogas residues achieved mineral fertilizer equivalents of 30 - 45 %. Overall, the untreated biogas residues showed a slightly increased N efficiency compared to cattle manure, whereas particularly site-dependent differences resulted in large differences in N efficiency of biogas residues.

Study of thermal conductivity of multilayer insulation

International Nuclear Information System (INIS)

Dutta, D.; Sundaram, S.; Nath, G.K.; Sethuram, N.P.; Chandrasekharan, T.; Varadarajan, T.G.

1994-01-01

This paper presents experimental determination of the apparent thermal conductivity of multilayer insulation for a cryogenic system. The variation of thermal conductivity with residual gas pressure is studied and the optimum vacuum for good insulating performance is determined. Evaporation loss technique for heat-inleak determination is employed. (author)

Long-term stabilization of crop residues and soil organic carbon affected by residue quality and initial soil pH.

Science.gov (United States)

Wang, Xiaojuan; Butterly, Clayton R; Baldock, Jeff A; Tang, Caixian

2017-06-01

Residues differing in quality and carbon (C) chemistry are presumed to contribute differently to soil pH change and long-term soil organic carbon (SOC) pools. This study examined the liming effect of different crop residues (canola, chickpea and wheat) down the soil profile (0-30cm) in two sandy soils differing in initial pH as well as the long-term stability of SOC at the amended layer (0-10cm) using mid-infrared (MIR) and solid-state 13 C nuclear magnetic resonance (NMR) spectroscopy. A field column experiment was conducted for 48months. Chickpea- and canola-residue amendments increased soil pH at 0-10cm in the Podzol by up to 0.47 and 0.36units, and in the Cambisol by 0.31 and 0.18units, respectively, at 48months when compared with the non-residue-amended control. The decomposition of crop residues was greatly retarded in the Podzol with lower initial soil pH during the first 9months. The MIR-predicted particulate organic C (POC) acted as the major C sink for residue-derived C in the Podzol. In contrast, depletion of POC and recovery of residue C in MIR-predicted humic organic C (HOC) were detected in the Cambisol within 3months. Residue types showed little impact on total SOC and its chemical composition in the Cambisol at 48months, in contrast to the Podzol. The final HOC and resistant organic C (ROC) pools in the Podzol amended with canola and chickpea residues were about 25% lower than the control. This apparent priming effect might be related to the greater liming effect of these two residues in the Podzol. Copyright © 2017 Elsevier B.V. All rights reserved.

Ivacaftor: A Novel Gene-Based Therapeutic Approach for Cystic Fibrosis

OpenAIRE

Condren, Michelle E.; Bradshaw, Marquita D.

2013-01-01

Ivacaftor is a new therapeutic agent that acts at the cystic fibrosis transmembrane conductance regulator (CFTR) channel to alter activity. It is approved for use in patients 6 years and older with cystic fibrosis who have at least 1 G551D mutation in the CFTR gene. It is unlike any other current pharmacologic agent for cystic fibrosis in that it specifically targets the gene defect associated with cystic fibrosis as opposed to treating resulting symptomology. Mucoactive agents, antibiotics, ...

Study of thermal conductivity of multilayer insulation

Energy Technology Data Exchange (ETDEWEB)

Dutta, D; Sundaram, S; Nath, G K; Sethuram, N P; Chandrasekharan, T; Varadarajan, T G [Heavy Water Division, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

This paper presents experimental determination of the apparent thermal conductivity of multilayer insulation for a cryogenic system. The variation of thermal conductivity with residual gas pressure is studied and the optimum vacuum for good insulating performance is determined. Evaporation loss technique for heat-inleak determination is employed. (author). 3 refs., 3 figs.

Comparison of destructive and nondestructive assay of heterogeneous salt residues

International Nuclear Information System (INIS)

Fleissner, J.G.; Hume, M.W.

1986-01-01

To study problems associated with nondestructive assay (NDA) measurements of molten salt residues, a joint study was conducted by the Rocky Flats Plant, Golden, CO and Mound Laboratories, Miamisburg, OH. Extensive NDA measurements were made on nine containers of molten salt residues by both Rocky Flats and Mound followed by dissolution and solution quantification at Rocky Flats. Results of this study verify that plutonium and americium can be measured in such salt residues by a new gamma-ray spectral analysis technique coupled with calorimetry. Biases with respect to the segmented gamma-scan technique were noted

Assessment of pesticide residues on selected vegetables of Pakistan

International Nuclear Information System (INIS)

Khan, M.S.; Shah, M.M.

2011-01-01

The present study was conducted to determine the pesticide residues on selected summer vegetables. Five vegetables were grown with three replicates in a split plot randomized complete block design. Pesticides were sprayed on vegetables thrice at regular intervals each after 15 days. At maturity the pesticides residues were extracted from edible and leaf portions using anhydrous sodium sulfate and ethyl acetate while adsorption chromatography technique was used for cleanup. The extracts were subjected to high performance liquid chromatography (HPLC) for separation and analysis of the compounds. Significant differences (p<0.05) were found in the pesticides residues on edible portions whereas highly significant differences (p<0.001) were observed for the leafy portions. The residual level of cypermethrin was highest (16.2 mg kg/sup -1/) in edible portion of bitter gourd, while Lambdacyhalothrin and Mancozeb residues were detected high (4.50 mg kg/sup -1/, 6.26 mg kg/sup -1/) in edible portion of bitter gourd and Cucumber respectively. Cypermethrin residues were high (1.86 mg kg/sup -1/) in Okra leaves. Mancozeb and Lambdacyhalothrin residual level was high (1.23 mg kg/sup -1/, and 0.0002 mg kg/sup -1/) in chili and tomato leaves. Cypermethrin residues were readily detected in edible and leaf portion of the selected vegetables. (author)

Experimental study of thermal conductivity of pyrolysised materials by means of a flat layer

Science.gov (United States)

Vaniushkin, V. D.; Popov, S. K.; Sidenkov, D. V.

2017-11-01

Recycling of tires is currently a very important task. One of the areas of recycling tires is their low-temperature pyrolysis to produce marketable products - liquid fraction and a solid coke residue. For the development of the pyrolysis installation it is important to know the thermal conductivity of the coke residue at different temperatures of pyrolysis of initial material. As a property of matter, thermal conductivity depends in general on temperature and pressure. For materials with some structure, such as porous materials, the thermal conductivity depends on the characteristics of the structure. The thermal conductivity of the porous coke residue at pyrolysis temperatures of 300 0C, 400 0C, 500 0C and atmospheric pressure was studied experimentally at the laboratory unit of the department of “Theoretical basis of heat engineering” using the method of the flat layer in the temperature range 5…100 0C. Experimentally proved temperature dependencies of the coefficient of thermal conductivity of the coke residue are built to improve the accuracy of calculations of constructive and regime parameters of the pyrolysis installation.

Relative availability of crop residue-N in rice cultivation

International Nuclear Information System (INIS)

Sirwando, H; Abdullah, N.

1988-01-01

The use of plant residues for soil amendment will reduce the use of chemical fertilizers. The experiment to study the uptake of N from various plant residues by rice crop. Three kinds of plant residue of soybean labelled with 15-N. Four levels of urea (0, 15, 30, 40 kg N/ha) were applied to aluvial soil from Pusakanegara. The factorial experiment was conducted in fully randomize design, with plant residues as the main treatment, and rate of urea as substreatment. The results obtained from this experiment showed that plant dry weight, N content of grain, straw, and the whole plant of Atomita I rice treated with soybean strow seens to be higher than those treated with the straw of rice or corn. (author). 6 refs.; 7 tabs

Calcination/dissolution residue treatment

International Nuclear Information System (INIS)

Knight, R.C.; Creed, R.F.; Patello, G.K.; Hollenberg, G.W.; Buehler, M.F.; O'Rourke, S.M.; Visnapuu, A.; McLaughlin, D.F.

1994-09-01

Currently, high-level wastes are stored underground in steel-lined tanks at the Hanford site. Current plans call for the chemical pretreatment of these wastes before their immobilization in stable glass waste forms. One candidate pretreatment approach, calcination/dissolution, performs an alkaline fusion of the waste and creates a high-level/low-level partition based on the aqueous solubilities of the components of the product calcine. Literature and laboratory studies were conducted with the goal of finding a residue treatment technology that would decrease the quantity of high-level waste glass required following calcination/dissolution waste processing. Four elements, Fe, Ni, Bi, and U, postulated to be present in the high-level residue fraction were identified as being key to the quantity of high-level glass formed. Laboratory tests of the candidate technologies with simulant high-level residues showed reductive roasting followed by carbonyl volatilization to be successful in removing Fe, Ni, and Bi. Subsequent bench-scale tests on residues from calcination/dissolution processing of genuine Hanford Site tank waste showed Fe was separated with radioelement decontamination factors of 70 to 1,000 times with respect to total alpha activity. Thermodynamic analyses of the calcination of five typical Hanford Site tank waste compositions also were performed. The analyses showed sodium hydroxide to be the sole molten component in the waste calcine and emphasized the requirement for waste blending if fluid calcines are to be achieved. Other calcine phases identified in the thermodynamic analysis indicate the significant thermal reconstitution accomplished in calcination

Effect of Solder Flux Residues on Corrosion of Electronics

DEFF Research Database (Denmark)

Hansen, Kirsten Stentoft; Jellesen, Morten Stendahl; Møller, Per

2009-01-01

Flux from ‘No Clean’ solder processes can cause reliability problems in the field due to aggressive residues, which may be electrical conducting or corrosive in humid environments. The solder temperature during a wave solder process is of great importance to the amount of residues left on a PCBA...... testing and use in the field, consequences and recommendations are given. Failures, caused by harsh[1] customer environments, are not covered in this paper....

Prevention of secretory diarrhea by ethanol extract of Bistortae rhizoma through inhibition of chloride channel

Directory of Open Access Journals (Sweden)

Bo Yu

2015-08-01

Full Text Available Inhibition of cystic fibrosis transmembrane conductance regulator (CFTR and Ca2+-activated Cl- channel (CaCC represents an attractive approach for the treatment of secretory diarrhea. The aim of the study is to investigate the molecular basis of the anti-diarrheal effect of traditional Chinese herbal anti-diarrheal medicine Bistortae rhizoma. Fluorescence quenching assay indicated that the 40% methanol /water fraction (D5 dose-dependently inhibited both CFTR and CaCC function in transfected Fischer rat thyroid (FRT cells. Ex vivo studies indicated that D5 inhibited both forskolin (FSK-activated CFTR current and CCh-induced CaCC current in rat colonic mucosa. In the mouse closed-loop model, intraluminal application of D5 (200 µg/mL significantly reduced cholera toxin-stimulated fluid secretion. In the intestinal motility model, D5 significantly delayed intestinal peristalsis in mice. Our research suggests that CFTR and CaCC-mediated intestinal epithelial Cl- secretion inhibiting and gastrointestinal motility delaying may account for the anti-diarrheal activity of B. rhizoma.

Co-ordinate regulation of the cystic fibrosis and multidrug resistance genes in cystic fibrosis knockout mice.

Science.gov (United States)

Trezise, A E; Ratcliff, R; Hawkins, T E; Evans, M J; Freeman, T C; Romano, P R; Higgins, C F; Colledge, W H

1997-04-01

The cystic fibrosis (Cftr and multidrug resistance (Mdr1) genes encode structurally similar proteins which are members of the ABC transporter superfamily. These genes exhibit complementary patterns of expression in vivo, suggesting that the regulation of their expression may be co-ordinated. We have tested this hypothesis in vivo by examining Cftr and Mdr1 expression in cystic fibrosis knockout transgenic mice (Cftr(tm1CAM)). Cftr mRNA expression in Cftr(tm1CAM)/Cftr(tm1CAM) mice was 4-fold reduced in the intestine, as compared with littermate wild-type mice. All other Cftr(tm1CAM)/Cftr(tm1CAM) mouse tissues examined showed similar reductions in Cftr expression. In contrast, we observed a 4-fold increase in Mdr1 mRNA expression in the intestines of neonatal and 3- to 4-week-old Cftr(tm1CAM)/Cftr(tm1CAM) mice, as compared with age-matched +/+ mice, and an intermediate level of Mdr1 mRNA in heterozygous Cftr(tm1CAM) mice. In 10-week-old, Cftr(tm1CAM)/Cftr(tm1CAM) mice and in contrast to the younger mice, Mdr1 mRNA expression was reduced, by 3-fold. The expression of two control genes, Pgk-1 and Mdr2, was similar in all genotypes, suggesting that the changes in Mdr1 mRNA levels observed in the Cftr(tm1CAM)/Cftr(tm1CAM) mice are specific to the loss of Cftr expression and/or function. These data provide further evidence supporting the hypothesis that the regulation Cftr and Mdr1 expression is co-ordinated in vivo, and that this co-ordinate regulation is influenced by temporal factors.

Evaluation of low-residue soldering for military and commercial applications: A report from the Low-Residue Soldering Task Force

Energy Technology Data Exchange (ETDEWEB)

Iman, R.L.; Anderson, D.J. [Sandia National Labs., Albuquerque, NM (United States); Burress, R.V. [SEHO (United States)] [and others

1995-06-01

The LRSTF combined the efforts of industry, military, and government to evaluate low-residue soldering processes for military and commercial applications. These processes were selected for evaluation because they provide a means for the military to support the presidential mandate while producing reliable hardware at a lower cost. This report presents the complete details and results of a testing program conducted by the LRSTF to evaluate low-residue soldering for printed wiring assemblies. A previous informal document provided details of the test plan used in this evaluation. Many of the details of that test plan are contained in this report. The test data are too massive to include in this report, however, these data are available on disk as Excel spreadsheets upon request. The main purpose of low-residue soldering is to eliminate waste streams during the manufacturing process.

A proposed residual stress model for oblique turning

International Nuclear Information System (INIS)

Elkhabeery, M. M.

2001-01-01

A proposed mathematical model is presented for predicting the residual stresses caused by turning. Effects of change in tool free length, cutting speed, feed rate, and the tensile strength of work piece material on the maximum residual stress are investigated. The residual stress distribution in the surface region due to turning under unlubricated condition is determined using a deflection etching technique. To reduce the number of experiments required and build the mathematical model for these variables, Response Surface Methodology (RSM) is used. In addition, variance analysis and an experimental check are conducted to determine the prominent parameters and the adequacy of the model. The results show that the tensile stress of the work piece material, cutting speed, and feed rate have significant effects on the maximum residual stresses. The proposed model, that offering good correlation between the experimental and predicted results, is useful in selecting suitable cutting parameters for the machining of different materials. (author)

Residue studies of Methabenzthiazuron in Soil, Lentils and Hay

International Nuclear Information System (INIS)

Al-Maghrabi, K.I.

2002-01-01

Over two years, replicate plots of lentils (Lens culinaris L.) were treated before seeding with methabenzthiazuron at a rate of 0.5 kg a.i. ha-1. In each year representative soil, lentil and hay samples were randomly collected from plots of each treatment. Soil samples were tested for residues 24 hours after treatment and harvest. Lentil and hay samples were tested at harvest. A cleanup step was conducted after extraction. Gas chromatograph equipped with a nitrogen/phosphorus detector was used to detect methabenzthiazuron. Overall average of residue levels in soil decreased significantly from 1.16+-0.15 mg kg, 24 hours after treatment, 0.12 +-0.01 mg kg at harvest. No significant difference in the maximum average residue was found in lentil and hay samples collected from various plots and tested at harvest (0.10+-0.01 and 0.19 +-0.02 mg kg in lentils and hay, respectively). Recovery tests were conducted with each group of samples tested in order to determine the efficiency of analytical procedure. (author)

PDE5 Inhibitors As Potential Tools In The Treatment Of Cystic Fibrosis

Directory of Open Access Journals (Sweden)

Sabrina eNoel

2012-09-01

Full Text Available Despite great advances in the understanding of the genetics and pathophysiology of cystic fibrosis (CF, there is still no cure for the disease. Using phosphodiesterase type 5 (PDE5 inhibitors, we and others have provided evidence of rescued F508del-CFTR trafficking and corrected deficient chloride transport activity. Studies using PDE5 inhibitors in mice homozygous for the clinically relevant F508del mutation have been conducted with the aim of restoring F508del-CFTR protein function. We demonstrated, by measuring transepithelial nasal potential difference in F508del mice following intraperitoneal injection of sildenafil, vardenafil or taladafil at clinical doses are able to restore the decreased CFTR-dependent chloride transport across the nasal mucosa. Moreover, vardenafil, but not sildenafil, stimulates chloride transport through the normal CFTR protein. We developed a specific nebulizer setup for mice, with which we demonstrated, through a single inhalation of PDE5 inhibitors, local activation of CFTR protein in CF. Significant potential advantages of inhalation drug therapy over oral or intravenous routes include rapid onset of pharmacological action, reduced systemic secondary effects and reduced effective drug doses compared to the drug delivered orally; this underlines the relevance and impact of our work for translational science. More recently, we analyzed the bronchoalveolar lavage of CF and wild-type mice for cell infiltrates and expression of pro-inflammatory cytokines and chemokines; we found that the CFTR activating effect of vardenafil, selected as a representative long-lasting PDE5 inhibitor, breaks the vicious circle of lung inflammation which plays a major role in morbi-mortality in CF. Our data highlight the potential use of PDE5 inhibitors in CF. Therapeutic approaches using clinically approved PDE5 inhibitors to address F508del-CFTR defects could speed up the development of new therapies for CF.

Eddy Current Nondestructive Residual Stress Assessment in Shot-Peened Nickel-Base Superalloys

International Nuclear Information System (INIS)

Blodgett, M.P.; Yu, F.; Nagy, P.B.

2005-01-01

Shot peening and other mechanical surface enhancement methods improve the fatigue resistance and foreign-object damage tolerance of metallic components by introducing beneficial near-surface compressive residual stresses and hardening the surface. However, the fatigue life improvement gained via surface enhancement is not explicitly accounted for in current engine component life prediction models because of the lack of accurate and reliable nondestructive methods that could verify the presence of compressive near-surface residual stresses in shot-peened hardware. In light of its frequency-dependent penetration depth, the measurement of eddy current conductivity has been suggested as a possible means to allow the nondestructive evaluation of subsurface residual stresses in surface-treated components. This technique is based on the so-called piezoresistivity effect, i.e., the stress-dependence of electrical resistivity. We found that, in contrast with most other materials, surface-treated nickel-base superalloys exhibit an apparent increase in electrical conductivity at increasing inspection frequencies, i.e., at decreasing penetration depths. Experimental results are presented to illustrate that the excess frequency-dependent apparent eddy current conductivity of shot-peened nickel-base superalloys can be used to estimate the absolute level and penetration depth of the compressive residual stress layer both before and after partial thermal relaxation

Review on Sources and Handling Method of Pesticide Residues in Animal Products

Directory of Open Access Journals (Sweden)

Indraningsih

2006-06-01

Full Text Available Field studies and literature search showed that some pesticide residues either organochlorines (OC or organophosphates (OP were detected in animal products (meat and milk . Pesticide residues in meat collected from West Java were detected at the level of 0 .8 ppb lindane and 62 ppb diazinon . While in meat from Lampung was detected at the level of 7 ppb lindane . 2 .7 heptachlor, 0 .8 endosulfan and 0 .5 ppb aldrin . Furthermore, pesticide residues were also detected in the milk collected from West, Central and East Java . The levels of lindane were 2,3 ; 15,9 ; 0,2 ppb ; heptachlor 8 ; 0 .4 and 0,05 ppb; diazinon 8 ; 0 and 1,8 ppb; CPM 0,4 ; 0,8 and 0 ppb ; endosulfan 0,1 ; 0,04 and 0,05 ppb for West, Central and East Java, respectively . The source of pesticide contamination in animal products is generally originated from feed materials, fodders . contaminated soils and water around the farm areas . Minimalization approach of pesticide residues in animal products could be conducted integratedly, such as through chemical process, biodegradation using microorganisms . Organic farming system is recognised as an alternative that may be applied to minimise contamination on agricultural land, eventually reducing pesticide residues in the agricultural products . Feeding with organic agricultural by-products with low pesticide residues appears to reduce pesticide residues in animal products . In order to eliminate pesticide contamination in soil, it has to be conducted progressively by implementing sustainable organic farming .

Evaluation of heavy metals in hazardous automobile shredder residue thermal residue and immobilization with novel nano-size calcium dispersed reagent

International Nuclear Information System (INIS)

Lee, Chi-Hyeon; Truc, Nguyen Thi Thanh; Lee, Byeong-Kyu; Mitoma, Yoshiharu; Mallampati, Srinivasa Reddy

2015-01-01

Graphical abstract: Schematic representation of possible mechanisms determining the heavy metals immobilization efficiencyof ASR dust/thermal residues after treatment with nanometallic Ca/CaO/PO 4 . - Highlights: • Nanometallic Ca/CaO/PO 4 for heavy metals immobilization in ASR residue. • Heavy metals immobilization in dry condition attained about 95–100%. • Remaining heavy metals were lower than the Korean standard regulatory limit. • The amounts of heavy metals detectable on the ASR dust surface decreased. • Nanometallic Ca/CaO/PO 4 has a promising potential for heavy metal remediation. - Abstract: This study was conducted to synthesize and apply a nano-size calcium dispersed reagent as an immobilization material for heavy metal-contaminated automobile shredder residues (ASR) dust/thermal residues in dry condition. Simple mixing with a nanometallic Ca/CaO/PO 4 dispersion mixture immobilized 95–100% of heavy metals in ASR dust/thermal residues (including bottom ash, cavity ash, boiler and bag filter ash). The quantity of heavy metals leached from thermal residues after treatment by nanometallic Ca/CaO/PO 4 was lower than the Korean standard regulatory limit for hazardous waste landfills. The morphology and elemental composition of the nanometallic Ca/CaO-treated ASR residue were characterized by field emission scanning election microscopy combined with electron dispersive spectroscopy (FE-SEM/EDS). The results indicated that the amounts of heavy metals detectable on the ASR thermal residue surface decreased and the Ca/PO 4 mass percent increased. X-ray diffraction (XRD) pattern analysis indicated that the main fraction of enclosed/bound materials on ASR residue included Ca/PO 4 − associated crystalline complexes, and that immobile Ca/PO 4 salts remarkably inhibited the desorption of heavy metals from ASR residues. These results support the potential use of nanometallic Ca/CaO/PO 4 as a simple, suitable and highly efficient material for the gentle

Evaluation of heavy metals in hazardous automobile shredder residue thermal residue and immobilization with novel nano-size calcium dispersed reagent

Energy Technology Data Exchange (ETDEWEB)

Lee, Chi-Hyeon; Truc, Nguyen Thi Thanh [Department of Civil and Environmental Engineering, University of Ulsan, Daehak-ro 93, Nam-gu, Ulsan 680-749 (Korea, Republic of); Lee, Byeong-Kyu, E-mail: bklee@ulsan.ac.kr [Department of Civil and Environmental Engineering, University of Ulsan, Daehak-ro 93, Nam-gu, Ulsan 680-749 (Korea, Republic of); Mitoma, Yoshiharu [Department of Environmental Sciences, Prefectural University of Hiroshima, 562 Nanatsuka-Cho Shobara City, Hiroshima 727-0023 (Japan); Mallampati, Srinivasa Reddy, E-mail: srireddys@ulsan.ac.kr [Department of Civil and Environmental Engineering, University of Ulsan, Daehak-ro 93, Nam-gu, Ulsan 680-749 (Korea, Republic of)

2015-10-15

Graphical abstract: Schematic representation of possible mechanisms determining the heavy metals immobilization efficiencyof ASR dust/thermal residues after treatment with nanometallic Ca/CaO/PO{sub 4}. - Highlights: • Nanometallic Ca/CaO/PO{sub 4} for heavy metals immobilization in ASR residue. • Heavy metals immobilization in dry condition attained about 95–100%. • Remaining heavy metals were lower than the Korean standard regulatory limit. • The amounts of heavy metals detectable on the ASR dust surface decreased. • Nanometallic Ca/CaO/PO{sub 4} has a promising potential for heavy metal remediation. - Abstract: This study was conducted to synthesize and apply a nano-size calcium dispersed reagent as an immobilization material for heavy metal-contaminated automobile shredder residues (ASR) dust/thermal residues in dry condition. Simple mixing with a nanometallic Ca/CaO/PO{sub 4} dispersion mixture immobilized 95–100% of heavy metals in ASR dust/thermal residues (including bottom ash, cavity ash, boiler and bag filter ash). The quantity of heavy metals leached from thermal residues after treatment by nanometallic Ca/CaO/PO{sub 4} was lower than the Korean standard regulatory limit for hazardous waste landfills. The morphology and elemental composition of the nanometallic Ca/CaO-treated ASR residue were characterized by field emission scanning election microscopy combined with electron dispersive spectroscopy (FE-SEM/EDS). The results indicated that the amounts of heavy metals detectable on the ASR thermal residue surface decreased and the Ca/PO{sub 4} mass percent increased. X-ray diffraction (XRD) pattern analysis indicated that the main fraction of enclosed/bound materials on ASR residue included Ca/PO{sub 4}− associated crystalline complexes, and that immobile Ca/PO{sub 4} salts remarkably inhibited the desorption of heavy metals from ASR residues. These results support the potential use of nanometallic Ca/CaO/PO{sub 4} as a simple, suitable and

Persistence and bioaccumulation of oxyfluorfen residues in onion.

Science.gov (United States)

Sondhia, Shobha

2010-03-01

A field study was conducted to determine persistence and bioaccumulation of oxyflorfen residues in onion crop at two growth stages. Oxyfluorfen (23.5% EC) was sprayed at 250 and 500 g ai/ha on the crop (variety, N53). Mature onion and soil samples were collected at harvest. Green onion were collected at 55 days from each treated and control plot and analyzed for oxyfluorfen residues by a validated high-performance liquid chromatography method with an accepted recovery of 78-92% at the minimum detectable concentration of 0.003 microg g(-1). Analysis showed 0.015 and 0.005 microg g(-1) residues of oxyfluorfen at 250 g a.i. ha(-1) rate in green and mature onion samples, respectively; however, at 500 g a.i.ha(-1) rates, 0.025 and 0.011 microg g(-1) of oxyfluorfen residues were detected in green and mature onion samples, respectively. Soil samples collected at harvest showed 0.003 and 0.003 microg g(-1) of oxyfluorfen residues at the doses 250 and 500 g a.i. ha(-1), respectively. From the study, a pre-harvest interval of 118 days for onion crop after the herbicide application is suggested.

Pesticide residue quantification analysis by hyperspectral imaging sensors

Science.gov (United States)

Liao, Yuan-Hsun; Lo, Wei-Sheng; Guo, Horng-Yuh; Kao, Ching-Hua; Chou, Tau-Meu; Chen, Junne-Jih; Wen, Chia-Hsien; Lin, Chinsu; Chen, Hsian-Min; Ouyang, Yen-Chieh; Wu, Chao-Cheng; Chen, Shih-Yu; Chang, Chein-I.

2015-05-01

Pesticide residue detection in agriculture crops is a challenging issue and is even more difficult to quantify pesticide residue resident in agriculture produces and fruits. This paper conducts a series of base-line experiments which are particularly designed for three specific pesticides commonly used in Taiwan. The materials used for experiments are single leaves of vegetable produces which are being contaminated by various amount of concentration of pesticides. Two sensors are used to collected data. One is Fourier Transform Infrared (FTIR) spectroscopy. The other is a hyperspectral sensor, called Geophysical and Environmental Research (GER) 2600 spectroradiometer which is a batteryoperated field portable spectroradiometer with full real-time data acquisition from 350 nm to 2500 nm. In order to quantify data with different levels of pesticide residue concentration, several measures for spectral discrimination are developed. Mores specifically, new measures for calculating relative power between two sensors are particularly designed to be able to evaluate effectiveness of each of sensors in quantifying the used pesticide residues. The experimental results show that the GER is a better sensor than FTIR in the sense of pesticide residue quantification.

Laser in situ keratomileusis for residual hyperopic astigmatism after conductive keratoplasty.

Science.gov (United States)

Kymionis, George D; Aslanides, Ioannis M; Khoury, Aghlab N; Markomanolakis, Marinos M; Naoumidi, Tatiana; Pallikaris, loannis G

2004-01-01

To report a case of laser in situ keratomileusis (LASIK) in a patient with previous conductive keratoplasty. A 48-year-old man underwent conductive keratoplasty for low hyperopic astigmatism (manifest refraction OD: +2.25 -0.50 x 77 degrees; OS: +2.50 -0.50 x 105 degrees). Three months postoperatively, UCVA was 20/25 and BSCVA was 20/20 in both eyes; manifest refraction OD: -0.25 -0.75 x 110 degrees; OS: +0.75 -0.75 x 50 degrees. Sixteen months after the operation, regression of refractive outcome was (manifest) OD: +1.75 -1.25 x 90 degrees; OS: +2.50 -0.50 x 85 degrees; UCVA was 20/40 in the right eye and 20/63 in the left eye and BSCVA was 20/20 in both eyes. LASIK was performed for hyperopic regression in the left eye using an automated microkeratome (Alcon SKBM, 130-microm plate; Aesculap-Meditec MEL 70 excimer laser). LASIK was uneventful and no intraoperative or postoperative complications related to the previous conductive keratoplasty procedure or LASIK were observed. Three months after LASIK and 19 months after the initial conductive keratoplasty, the patient's left eye was emmetropic; UCVA was 20/20(-2), BSCVA was 20/20 and manifest refraction was +0.25 -0.25 x 35 degrees. There was a uniform increase in topographical steepening. Visual acuity, refraction and topographic findings remained unchanged at 6 months. Even though our experience is limited, treatment of hyperopia with LASIK in an eye with refractive regression following previous conductive keratoplasty resulted in a predicted refractive outcome, with no complications, and improvement in visual acuity at 6 months follow-up.

Effects of residual hearing on cochlear implant outcomes in children: A systematic-review.

Science.gov (United States)

Chiossi, Julia Santos Costa; Hyppolito, Miguel Angelo

2017-09-01

to investigate if preoperative residual hearing in prelingually deafened children can interfere on cochlear implant indication and outcomes. a systematic-review was conducted in five international databases up to November-2016, to locate articles that evaluated cochlear implantation in children with some degree of preoperative residual hearing. Outcomes were auditory, language and cognition performances after cochlear implant. The quality of the studies was assessed and classified according to the Oxford Levels of Evidence table - 2011. Risk of biases were also described. From the 30 articles reviewed, two types of questions were identified: (a) what are the benefits of cochlear implantation in children with residual hearing? (b) is the preoperative residual hearing a predictor of cochlear implant outcome? Studies ranged from 04 to 188 subjects, evaluating populations between 1.8 and 10.3 years old. The definition of residual hearing varied between studies. The majority of articles (n = 22) evaluated speech perception as the outcome and 14 also assessed language and speech production. There is evidence that cochlear implant is beneficial to children with residual hearing. Preoperative residual hearing seems to be valuable to predict speech perception outcomes after cochlear implantation, even though the mechanism of how it happens is not clear. More extensive researches must be conducted in order to make recommendations and to set prognosis for cochlear implants based on children preoperative residual hearing. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of Pesticide Residues in Cannabis Smoke

Directory of Open Access Journals (Sweden)

Nicholas Sullivan

2013-01-01

Full Text Available The present study was conducted in order to quantify to what extent cannabis consumers may be exposed to pesticide and other chemical residues through inhaled mainstream cannabis smoke. Three different smoking devices were evaluated in order to provide a generalized data set representative of pesticide exposures possible for medical cannabis users. Three different pesticides, bifenthrin, diazinon, and permethrin, along with the plant growth regulator paclobutrazol, which are readily available to cultivators in commercial products, were investigated in the experiment. Smoke generated from the smoking devices was condensed in tandem chilled gas traps and analyzed with gas chromatography-mass spectrometry (GC-MS. Recoveries of residues were as high as 69.5% depending on the device used and the component investigated, suggesting that the potential of pesticide and chemical residue exposures to cannabis users is substantial and may pose a significant toxicological threat in the absence of adequate regulatory frameworks.

Residual stresses

International Nuclear Information System (INIS)

Sahotra, I.M.

2006-01-01

The principal effect of unloading a material strained into the plastic range is to create a permanent set (plastic deformation), which if restricted somehow, gives rise to a system of self-balancing within the same member or reaction balanced by other members of the structure., known as residual stresses. These stresses stay there as locked-in stresses, in the body or a part of it in the absence of any external loading. Residual stresses are induced during hot-rolling and welding differential cooling, cold-forming and extruding: cold straightening and spot heating, fabrication and forced fitting of components constraining the structure to a particular geometry. The areas which cool more quickly develop residual compressive stresses, while the slower cooling areas develop residual tensile stresses, and a self-balancing or reaction balanced system of residual stresses is formed. The phenomenon of residual stresses is the most challenging in its application in surface modification techniques determining endurance mechanism against fracture and fatigue failures. This paper discusses the mechanism of residual stresses, that how the residual stresses are fanned and what their behavior is under the action of external forces. Such as in the case of a circular bar under limit torque, rectangular beam under limt moment, reclaiming of shafts welds and peening etc. (author)

Valorization of Furfural Residue by Hydrothermal Carbonization

DEFF Research Database (Denmark)

Yue, Fen; Zhang, Jia; Pedersen, Christian Marcus

2017-01-01

Furfural residue (FR) is a low-cost by-product generated in the furfural production from corncobs, which is mainly composed of cellulose and lignin. In this report, hydrothermal carbonization (HTC) of deashed FR was conducted at various reaction temperatures (200, 220 and 240 °C) and reaction times...

Crystallization and Preliminary Diffraction Analysis of the CAL PDZ Domain in Complex with a Selective Peptide Inhibitor

Energy Technology Data Exchange (ETDEWEB)

J Amacher; P Cushing; J Weiner; D Madden

2011-12-31

Cystic fibrosis (CF) is associated with loss-of-function mutations in the CF transmembrane conductance regulator (CFTR), which regulates epithelial fluid and ion homeostasis. The CFTR cytoplasmic C-terminus interacts with a number of PDZ (PSD-95/Dlg/ZO-1) proteins that modulate its intracellular trafficking and chloride-channel activity. Among these, the CFTR-associated ligand (CAL) has a negative effect on apical-membrane expression levels of the most common disease-associated mutant {Delta}F508-CFTR, making CAL a candidate target for the treatment of CF. A selective peptide inhibitor of the CAL PDZ domain (iCAL36) has recently been developed and shown to stabilize apical expression of {Delta}F508-CFTR, enhancing net chloride-channel activity, both alone and in combination with the folding corrector corr-4a. As a basis for structural studies of the CAL-iCAL36 interaction, a purification protocol has been developed that increases the oligomeric homogeneity of the protein. Here, the cocrystallization of the complex in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 35.9, b = 47.7, c = 97.3 {angstrom}, is reported. The crystals diffracted to 1.4 {angstrom} resolution. Based on the calculated Matthews coefficient (1.96 {angstrom}{sup 3} Da{sup -1}), it appears that the asymmetric unit contains two complexes.

EFFECTS OF MUCUNA ( MUCUNA UTILIS L.) RESIDUE ...

African Journals Online (AJOL)

The field experiment was conducted at two locations: University of Agriculture, Abeokuta (UNAAB) and Olowo-Papa (OP) in Ogun state both in Forest-savannah transition zone of Nigeria to investigate the response of three upland rice cultivars (O.sativa) to mucuna residue incorporation and Nitrogen (N) fertilizer and the ...

Effect of processing conditions on residual stress distributions by bead-on-plate welding after surface machining

International Nuclear Information System (INIS)

Ihara, Ryohei; Mochizuki, Masahito

2014-01-01

Residual stress is important factor for stress corrosion cracking (SCC) that has been observed near the welded zone in nuclear power plants. Especially, surface residual stress is significant for SCC initiation. In the joining processes of pipes, butt welding is conducted after surface machining. Residual stress is generated by both processes, and residual stress distribution due to surface machining is varied by the subsequent butt welding. In previous paper, authors reported that residual stress distribution generated by bead on plate welding after surface machining has a local maximum residual stress near the weld metal. The local maximum residual stress shows approximately 900 MPa that exceeds the stress threshold for SCC initiation. Therefore, for the safety improvement of nuclear power plants, a study on the local maximum residual stress is important. In this study, the effect of surface machining and welding conditions on residual stress distribution generated by welding after surface machining was investigated. Surface machining using lathe machine and bead on plate welding with tungsten inert gas (TIG) arc under various conditions were conducted for plate specimens made of SUS316L. Then, residual stress distributions were measured by X-ray diffraction method (XRD). As a result, residual stress distributions have the local maximum residual stress near the weld metal in all specimens. The values of the local maximum residual stresses are almost the same. The location of the local maximum residual stress is varied by welding condition. It could be consider that the local maximum residual stress is generated by same generation mechanism as welding residual stress in surface machined layer that has high yield stress. (author)

Residual stresses

International Nuclear Information System (INIS)

Macherauch, E.

1978-01-01

Residual stresses are stresses which exist in a material without the influence of external powers and moments. They come into existence when the volume of a material constantly changes its form as a consequence of mechanical, thermal, and/or chemical processes and is hindered by neighbouring volumes. Bodies with residual stress are in mechanical balance. These residual stresses can be manifested by means of all mechanical interventions disturbing this balance. Acoustical, optical, radiological, and magnetical methods involving material changes caused by residual stress can also serve for determining residual stress. Residual stresses have an ambivalent character. In technical practice, they are feared and liked at the same time. They cause trouble because they can be the cause for unexpected behaviour of construction elements. They are feared since they can cause failure, in the worst case with catastrophical consequences. They are appreciated, on the other hand, because, in many cases, they can contribute to improvements of the material behaviour under certain circumstances. But they are especially liked for their giving convenient and (this is most important) mostly uncontrollable explanations. For only in very few cases we have enough knowledge and possibilities for the objective evaluation of residual stresses. (orig.) [de

Residue management at Rocky Flats

International Nuclear Information System (INIS)

Olencz, J.

1995-01-01

Past plutonium production and manufacturing operations conducted at the Rocky Flats Environmental Technology Site (RFETS) produced a variety of plutonium-contaminated by-product materials. Residues are a category of these materials and were categorized as open-quotes materials in-processclose quotes to be recovered due to their inherent plutonium concentrations. In 1989 all RFETS plutonium production and manufacturing operations were curtailed. This report describes the management of plutonium bearing liquid and solid wastes

Evaluation of residue-residue contact predictions in CASP9

KAUST Repository

Monastyrskyy, Bohdan

2011-01-01

This work presents the results of the assessment of the intramolecular residue-residue contact predictions submitted to CASP9. The methodology for the assessment does not differ from that used in previous CASPs, with two basic evaluation measures being the precision in recognizing contacts and the difference between the distribution of distances in the subset of predicted contact pairs versus all pairs of residues in the structure. The emphasis is placed on the prediction of long-range contacts (i.e., contacts between residues separated by at least 24 residues along sequence) in target proteins that cannot be easily modeled by homology. Although there is considerable activity in the field, the current analysis reports no discernable progress since CASP8.

Biofertilizer potential of residual biomass of Akk (alotropis procera (Ait.))

International Nuclear Information System (INIS)

Ahmad, N.

2016-01-01

The biofertilizer potential of residual biomass, derived from two parts that is flowers and leaves of Akk,was investigated in terms of its applications as a substrate for phyto-beneficial bacterial growth and subsequent inorganic phosphate solubilizing agent. The residual biomass was obtained after the extraction of antioxidants from the leaves and flowers of Akk using different solvent systems. The treatment with residual biomass of Akk (RBA) significantly (p<0.05) enhanced the growth of Enterobacter sp. Fs-11 and Rhizobium sp. E-11 as compared to control (without residual biomass). Maximum microbial growth in terms of optical density (0.92-1.22) was observed for residual biomass sample extracted with aqueous acetone against the control (0.58-0.68). On the other hand, maximum phosphate solubilization (589.27-611.32 mu g mL-1) was recorded for aqueous ethanol extracted residual biomass while the minimum (246.31-382.15 micro g) for aqueous acetone extracted residual biomass against the control (576.65 micro g mL-1). The present study revealed that the tested RBA can be explored as an effective bio-inoculant to supplement synthetic inorganic phosphate fertilizers. However, some appropriate in-vitro assays should be conducted to optimize and standardize the quantity and mesh size of residual biomass prior to use in biofertilizer production as carrier material. (author)

Efficient Gene Delivery to Pig Airway Epithelia and Submucosal Glands Using Helper-Dependent Adenoviral Vectors

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Huibi Cao

2013-01-01

Full Text Available Airway gene delivery is a promising strategy to treat patients with life-threatening lung diseases such as cystic fibrosis (CF. However, this strategy has to be evaluated in large animal preclinical studies in order to translate it to human applications. Because of anatomic and physiological similarities between the human and pig lungs, we utilized pig as a large animal model to examine the safety and efficiency of airway gene delivery with helper-dependent adenoviral vectors. Helper-dependent vectors carrying human CFTR or reporter gene LacZ were aerosolized intratracheally into pigs under bronchoscopic guidance. We found that the LacZ reporter and hCFTR transgene products were efficiently expressed in lung airway epithelial cells. The transgene vectors with this delivery can also reach to submucosal glands. Moreover, the hCFTR transgene protein localized to the apical membrane of both ciliated and nonciliated epithelial cells, mirroring the location of wild-type CF transmembrane conductance regulator (CFTR. Aerosol delivery procedure was well tolerated by pigs without showing systemic toxicity based on the limited number of pigs tested. These results provide important insights into developing clinical strategies for human CF lung gene therapy.

Mechanisms of protein misfolding in conformational lung diseases.

LENUS (Irish Health Repository)

McElvaney, N G

2012-08-01

Genetic or environmentally-induced alterations in protein structure interfere with the correct folding, assembly and trafficking of proteins. In the lung the expression of misfolded proteins can induce a variety of pathogenetic effects. Cystic fibrosis (CF) and alpha-1 antitrypsin (AAT) deficiency are two major clinically relevant pulmonary disorders associated with protein misfolding. Both are genetic diseases the primary causes of which are expression of mutant alleles of the cystic fibrosis transmembrane conductance regulator (CFTR) and SERPINA1, respectively. The most common and best studied mutant forms of CFTR and AAT are ΔF508 CFTR and the Glu342Lys mutant of AAT called ZAAT, respectively. Non-genetic mechanisms can also damage protein structure and induce protein misfolding in the lung. Cigarette-smoke contains oxidants and other factors that can modify a protein\\'s structure, and is one of the most significant environmental causes of protein damage within the lung. Herein we describe the mechanisms controlling the folding of wild type and mutant versions of CFTR and AAT proteins, and explore the consequences of cigarette-smoke-induced effects on the protein folding machinery in the lung.

Decomposition of sugar cane crop residues under different nitrogen rates

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Douglas Costa Potrich

2014-09-01

Full Text Available The deposition of organic residues through mechanical harvesting of cane sugar is a growing practice in sugarcane production system. The maintenance of these residues on the soil surface depends mainly on environmental conditions. Nitrogen fertilization on dry residues tend to retard decomposition of these, providing benefits such as increased SOM. Thus, the object of this research was to evaluate the effect of different doses of nitrogen on sugar cane crop residues, as its decomposition and contribution to carbon sequestration in soil. The experiment was conducted in Dourados-MS and consisted of a randomized complete block design. Dried residues were placed in litter bags and the treatments were arranged in a split plot, being the four nitrogen rates (0, 50, 100 and 150 kg ha-1 N the plots, and the seven sampling times (0, 30, 60, 90, 120, 150 and 180 the spit plots. Decomposition rates of residues, total organic carbon and labile carbon on soil were analysed. The application of increasing N doses resulted in an increase in their decomposition rates. Despite this, note also the mineral N application as a strategy to get higher levels of labile carbon in soil.

New substrate containing agroindustrial carnauba residue for production of papaya under foliar fertilization

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Francisca G. Albano

Full Text Available ABSTRACT The use of organic waste in the composition of substrates for seedlings constitutes an alternative to the recycling of these materials. Thus, an experiment was conducted with the objective to evaluate the production of ‘Formosa’ papaya seedlings in substrate containing carnauba wax residue, under foliar fertilization. The experimental design was completely randomized with five replicates, with treatments distributed in a 5 x 2 factorial scheme, corresponding to five materials used as substrates, in the presence and absence of foliar fertilization. The materials used were: earthworm humus, carnauba residue + fresh rice husk; carnauba residue in powder; carnauba residue semi-decomposed and mixture of carnauba residues: carnauba residue + fresh rice husk + carnauba residue semi-decomposed + carnauba residue in powder, at the proportion 1:1:1. The agroindustrial residue of carnauba wax semi-decomposed can be used as substrates in the production of ‘Formosa’ papaya seedlings. The foliar fertilization increases the quality of papaya seedlings, leading to increment in leaf area, root volume and sulfur content in the leaves, thus becoming a necessary practice.

Improving residue-residue contact prediction via low-rank and sparse decomposition of residue correlation matrix.

Science.gov (United States)

Zhang, Haicang; Gao, Yujuan; Deng, Minghua; Wang, Chao; Zhu, Jianwei; Li, Shuai Cheng; Zheng, Wei-Mou; Bu, Dongbo

2016-03-25

Strategies for correlation analysis in protein contact prediction often encounter two challenges, namely, the indirect coupling among residues, and the background correlations mainly caused by phylogenetic biases. While various studies have been conducted on how to disentangle indirect coupling, the removal of background correlations still remains unresolved. Here, we present an approach for removing background correlations via low-rank and sparse decomposition (LRS) of a residue correlation matrix. The correlation matrix can be constructed using either local inference strategies (e.g., mutual information, or MI) or global inference strategies (e.g., direct coupling analysis, or DCA). In our approach, a correlation matrix was decomposed into two components, i.e., a low-rank component representing background correlations, and a sparse component representing true correlations. Finally the residue contacts were inferred from the sparse component of correlation matrix. We trained our LRS-based method on the PSICOV dataset, and tested it on both GREMLIN and CASP11 datasets. Our experimental results suggested that LRS significantly improves the contact prediction precision. For example, when equipped with the LRS technique, the prediction precision of MI and mfDCA increased from 0.25 to 0.67 and from 0.58 to 0.70, respectively (Top L/10 predicted contacts, sequence separation: 5 AA, dataset: GREMLIN). In addition, our LRS technique also consistently outperforms the popular denoising technique APC (average product correction), on both local (MI_LRS: 0.67 vs MI_APC: 0.34) and global measures (mfDCA_LRS: 0.70 vs mfDCA_APC: 0.67). Interestingly, we found out that when equipped with our LRS technique, local inference strategies performed in a comparable manner to that of global inference strategies, implying that the application of LRS technique narrowed down the performance gap between local and global inference strategies. Overall, our LRS technique greatly facilitates

CHARACTERIZING RESIDUE TRANSFER EFFICIENCIES USING A FLUORESCENT IMAGING TECHNIQUE

Science.gov (United States)

To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and indirect ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to identify the important parameters for chara...

Approaches for Modelling the Residual Service Life of Marine Concrete Structures

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Amir Rahimi

2014-01-01

Full Text Available This paper deals with the service life design of existing reinforced concrete structures in a marine environment. The general procedure of condition assessment for estimating the residual service life of structures before a repair measure is illustrated. For assessment of the residual service life of structures which have undergone a repair measure a simplified mathematical model of chloride diffusion in a 2-layer system is presented. Preliminary probabilistic calculations demonstrate the effect of various conditions on the residual service life. First studies of the chloride diffusion in a 2-layer system have been conducted using the finite element method. Results of a long-term exposure test are presented to illustrate the performance of two different repair materials. The distribution of residual chlorides after application of a repair material is being studied in laboratory investigations. The residual chlorides migrate from the concrete layer into the new layer immediately after the repair material has been applied to the concrete member. The content and gradient of residual chlorides, along with the thickness and the chloride ingress resistance of both the remaining and the new layer of cover, will determine the residual service life of the repaired structures.

Investigation of residual stress in laser welding dissimilar materials

International Nuclear Information System (INIS)

Mirim, Denilson de Camargo; Oliveira, Rene Ramos de; Berretta, Jose Roberto; Rossi, Wagner de; Lima, Nelson Batista de; Delijaicov, Sergio; Gomes, Diego Oliva

2010-01-01

One of the most critical problems found in the different materials welding is the residual stress formation, that happens mainly for the fact of those materials they possess coefficients of thermal expansion and different thermal conductivities. Like this in this work the residual tension was evaluated in the technique of welding laser among the steel low carbon, AISI 1010 and AISI 304. The materials were united for it welds autogenous of top with a laser of continuous Nd:YAG in that they were varied the potency, speed and the focus of the laser stayed constant in relation to surface of the sample. The main objective of the study went identification and to analysis of the residual stress in HAZ on both sides of seem. Um planning factorial of two factors at two levels each it was executed for optimization the combination of the factors potency and speed. The obtained answers were the residual stress in different depths in HAZ. In the surface of the sample measures of residual stress were accomplished by the technique of X-ray diffraction. The hole drilling strain gage method it was applied to measure the residual stress on both sides of the union. The results were analyzed using the variance analysis and the statistical regression based on the different influences of the entrance and combination of the factors in the residual stress generated in that union. The results indicate that the development of models can foresee the answers satisfactorily. (author)

The role of the UPS in cystic fibrosis

Directory of Open Access Journals (Sweden)

Cyr Douglas M

2007-11-01

Full Text Available Abstract CF is an inherited autosomal recessive disease whose lethality arises from malfunction of CFTR, a single chloride (Cl- ion channel protein. CF patients harbor mutations in the CFTR gene that lead to misfolding of the resulting CFTR protein, rendering it inactive and mislocalized. Hundreds of CF-related mutations have been identified, many of which abrogate CFTR folding in the endoplasmic reticulum (ER. More than 70% of patients harbor the ΔF508 CFTR mutation that causes misfolding of the CFTR proteins. Consequently, mutant CFTR is unable to reach the apical plasma membrane of epithelial cells that line the lungs and gut, and is instead targeted for degradation by the UPS. Proteins located in both the cytoplasm and ER membrane are believed to identify misfolded CFTR for UPS-mediated degradation. The aberrantly folded CFTR protein then undergoes polyubiquitylation, carried out by an E1-E2-E3 ubiquitin ligase system, leading to degradation by the 26S proteasome. This ubiquitin-dependent loss of misfolded CFTR protein can be inhibited by the application of ‘corrector’ drugs that aid CFTR folding, shielding it from the UPS machinery. Corrector molecules elevate cellular CFTR protein levels by protecting the protein from degradation and aiding folding, promoting its maturation and localization to the apical plasma membrane. Combinatory application of corrector drugs with activator molecules that enhance CFTR Cl- ion channel activity offers significant potential for treatment of CF patients. Publication history: Republished from Current BioData's Targeted Proteins database (TPdb; http://www.targetedproteinsdb.com.

Determination of properties of clean coal technology post-process residue

Directory of Open Access Journals (Sweden)

Agnieszka Klupa

2016-01-01

Full Text Available This article presents the possibilities of using modern measuring devices to determine the properties of process residues (Polish acronym: UPP. UPP was taken from the combustion process from a power plant in Silesia. Determining the properties of UPP is the basis for making decisions about its practical application, for example, as a raw material to obtain useful products such as: pozzolan, cenosphere or zeolite, for which there is demand. The development of advanced technology and science has given rise to modern and precise research tools that contribute to the development of appropriate methods to assess the properties of post-process residue. For this study the following were used: scanning electron microscope with EDS microanalysis and an analyzer for particle size-, shape- and number- analysis. The study conducted confirms the effectiveness of SEM analysis to determine the properties of post-process residue from Clean Coal Technologies (CCT. The results obtained are an introduction to further research on the determination of properties of CCT post-process residue. Research to determine the properties of CCT post-process residue only began relatively recently.

Decontamination of chlorantraniliprole residues on cabbage and cauliflower through household processing methods.

Science.gov (United States)

Kar, Abhijit; Mandal, Kousik; Singh, Balwinder

2012-04-01

A supervised field trial was conducted to study the residues of chlorantraniliprole on cabbage and cauliflower. Three applications of chlorantraniliprole at 10 days interval were made @ 9.25 and 18.50 g a.i. ha(-1). The samples of marketable size heads and curds of cabbage and cauliflower were collected at 0 and 1 day after the last application. QuEChERS sample preparation was used for the determination of chlorantraniliprole residues on cabbage heads and cauliflower curds. The residues of chlorantraniliprole were quantified by high performance liquid chromatography (HPLC) with photo diode array (PDA) detector and confirmed by high performance thin layer chromatography (HPTLC). Washing of cabbage and cauliflower with tap water removed about 17%-40% of chlorantraniliprole residues. However, boiling removed 100% of chlorantraniliprole residues on cabbage and cauliflower in both the cases.

Cl- channels in apoptosis

DEFF Research Database (Denmark)

Wanitchakool, Podchanart; Ousingsawat, Jiraporn; Sirianant, Lalida

2016-01-01

A remarkable feature of apoptosis is the initial massive cell shrinkage, which requires opening of ion channels to allow release of K(+), Cl(-), and organic osmolytes to drive osmotic water movement and cell shrinkage. This article focuses on the role of the Cl(-) channels LRRC8, TMEM16/anoctamin......, and cystic fibrosis transmembrane conductance regulator (CFTR) in cellular apoptosis. LRRC8A-E has been identified as a volume-regulated anion channel expressed in many cell types. It was shown to be required for regulatory and apoptotic volume decrease (RVD, AVD) in cultured cell lines. Its presence also......(-) channels or as regulators of other apoptotic Cl(-) channels, such as LRRC8. CFTR has been known for its proapoptotic effects for some time, and this effect may be based on glutathione release from the cell and increase in cytosolic reactive oxygen species (ROS). Although we find that CFTR is activated...

Chemical modifications of therapeutic proteins induced by residual ethylene oxide.

Science.gov (United States)

Chen, Louise; Sloey, Christopher; Zhang, Zhongqi; Bondarenko, Pavel V; Kim, Hyojin; Ren, Da; Kanapuram, Sekhar

2015-02-01

Ethylene oxide (EtO) is widely used in sterilization of drug product primary containers and medical devices. The impact of residual EtO on protein therapeutics is of significant interest in the biopharmaceutical industry. The potential for EtO to modify individual amino acids in proteins has been previously reported. However, specific identification of EtO adducts in proteins and the effect of residual EtO on the stability of therapeutic proteins has not been reported to date. This paper describes studies of residual EtO with two therapeutic proteins, a PEGylated form of the recombinant human granulocyte colony-stimulating factor (Peg-GCSF) and recombinant human erythropoietin (EPO) formulated with human serum albumin (HSA). Peg-GCSF was filled in an EtO sterilized delivery device and incubated at accelerated stress conditions. Glu-C peptide mapping and LC-MS analyses revealed residual EtO reacted with Peg-GCSF and resulted in EtO modifications at two methionine residues (Met-127 and Met-138). In addition, tryptic peptide mapping and LC-MS analyses revealed residual EtO in plastic vials reacted with HSA in EPO formulation at Met-328 and Cys-34. This paper details the work conducted to understand the effects of residual EtO on the chemical stability of protein therapeutics. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Thermal conductivity of the Lennard-Jones chain fluid model.

Science.gov (United States)

Galliero, Guillaume; Boned, Christian

2009-12-01

Nonequilibrium molecular dynamics simulations have been performed to estimate, analyze, and correlate the thermal conductivity of a fluid composed of short Lennard-Jones chains (up to 16 segments) over a large range of thermodynamic conditions. It is shown that the dilute gas contribution to the thermal conductivity decreases when the chain length increases for a given temperature. In dense states, simulation results indicate that the residual thermal conductivity of the monomer increases strongly with density, but is weakly dependent on the temperature. Compared to the monomer value, it has been noted that the residual thermal conductivity of the chain was slightly decreasing with its length. Using these results, an empirical relation, including a contribution due to the critical enhancement, is proposed to provide an accurate estimation of the thermal conductivity of the Lennard-Jones chain fluid model (up to 16 segments) over the domain 0.8values of the Lennard-Jones chain fluid model merge on the same "universal" curve when plotted as a function of the excess entropy. Furthermore, it is shown that the reduced configurational thermal conductivity of the Lennard-Jones chain fluid model is approximately proportional to the reduced excess entropy for all fluid states and all chain lengths.

Effects of storage and processing on residue levels of chlorpyrifos in soybeans.

Science.gov (United States)

Zhao, Liuwei; Ge, Jing; Liu, Fengmao; Jiang, Naiwen

2014-05-01

The residue levels of chlorpyrifos in soybeans during storage and processing were investigated. Soybeans were treated with chlorpyrifos aqueous solution and placed in a sealed plastic container. The residue of chlorpyrifos was determined in soybeans at six time points within 0 and 112days during storage and oil processing of the soybeans was conducted. The analysis of the residues of chlorpyrifos was carried out by gas chromatography-mass spectrometry (GC-MS). Results show that the dissipation of chlorpyrifos in soybeans is about 62% during the storage period. Moreover, the carryover of the residues from soybeans into oil is found to be related to the processing methods. Processing factor, which is defined as the ratio of chlorpyrifos residue concentration in oil sample to that in the soybean samples, was 11 and 0.25 after cold and hot pressing, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

Poor survival in rheumatoid arthritis associated with bronchiectasis: a family-based cohort study.

Directory of Open Access Journals (Sweden)

Xavier Puéchal

Full Text Available BACKGROUND: Diffuse bronchiectasis (DB may occur in rheumatoid arthritis (RA. CFTR (cystic fibrosis transmembrane conductance regulator mutations predispose RA patients to DB, but the prognosis of RA-associated DB (RA-DB is unclear. METHODS: We report long-term mortality data from a nationwide family-based association study of patients with RA only, DB only or RA-DB. We assessed mortality as a function of clinical characteristics and CF/CFTR-RD (CFTR-related disorders mutations in 137 subjects from 24 kindreds. Potential risk factors were investigated by Cox proportional-hazard analysis with shared Gaussian random effects to account for within-family correlations. RESULTS: During a median follow-up of 11 years after inclusion, 18 patients died, mostly from cardiorespiratory causes. Survival was significantly lower for RA-DB patients than for unaffected relatives and for patients with RA or DB only. RA patients with DB had also a poorer prognosis in terms of survival after RA diagnosis (HR, 8.6; 95% CI, 1.5-48.2; P = 0.014 and from birth (HR, 9.6; 95% CI, 1.1-81.7; P = 0.039. Early onset of DB (HR, 15.4; 95% CI, 2.1-113.2; P = 0.007 and CF/CFTR-RD mutation (HR, 7.2; 95% CI, 1.4-37.1; P = 0.018 were associated with poorer survival in patients with RA-DB. Thus, CF/CFTR-RD mutations in RA patients with early-onset DB defined a subgroup of high-risk patients with higher mortality rates (log-rank test P = 1.28×10(-5. CONCLUSION: DB is associated with poorer survival in patients with RA. Early-onset DB and CFTR mutations are two markers that identify RA patients at a high risk of death, for whom future therapeutic interventions should be designed and evaluated.

A comparison of residual stresses in built-up steel beams using hole-drilling method

International Nuclear Information System (INIS)

Nawafleh, M. A.; Hunaiti, Y. M.; Younes, R. M.

2009-01-01

Residual stresses have a significant effect on the stability resistance of metal building systems. An experimental program was conducted to measure these stresses in built-up steel beams using incremental hole-drilling method. The experimental results reveal that the predicted residual stress type of pattern for built-up I-sections with fillet welds on one side of the web is not the same as the pattern of residual stresses in built-up I-sections with fillet welds on both sides of the web

The potential of residues of furfural and biogas as calcareous soil amendments for corn seed production.

Science.gov (United States)

Zhao, Yunchen; Yan, Zhibin; Qin, Jiahai; Ma, Zhijun; Zhang, Youfu; Zhang, Li

2016-04-01

Intensive corn seed production in Northwest of China produced large amounts of furfural residues, which represents higher treatment cost and environmental issue. The broad calcareous soils in the Northwest of China exhibit low organic matter content and high pH, which led to lower fertility and lower productivity. Recycling furfural residues as soil organic and nutrient amendment might be a promising agricultural practice to calcareous soils. A 3-year field study was conducted to evaluate the effects of furfural as a soil amendment on corn seed production on calcareous soil with compared to biogas residues. Soil physical-chemical properties, soil enzyme activities, and soil heavy metal concentrations were assessed in the last year after the last application. Corn yield was determined in each year. Furfural residue amendments significantly decreased soil pH and soil bulk density. Furfural residues combined with commercial fertilizers resulted in the greater cumulative on soil organic matter, total phosphorus, available phosphorus, available potassium, and cation exchange capacity than that of biogas residue. Simultaneously, urease, invertase, catalase, and alkaline phosphatase increased even at the higher furfural application rates. Maize seed yield increased even with lower furfural residue application rates. Furfural residues resulted in lower Zn concentration and higher Cd concentration than that of biogas residues. Amendment of furfural residues led to higher soil electrical conductivity (EC) than that of biogas residues. The addition of furfural residues to maize seed production may be considered to be a good strategy for recycling the waste, converting it into a potential resource as organic amendment in arid and semi-arid calcareous soils, and may help to reduce the use of mineral chemical fertilizers in these soils. However, the impact of its application on soil health needs to be established in long-term basis.

Residual Stress Testing of Outer 3013 Containers

International Nuclear Information System (INIS)

Dunn, K.

2004-01-01

A Gas Tungsten Arc Welded (GTAW) outer 3013 container and a laser welded outer 3013 container have been tested for residual stresses according to the American Society for Testing Materials (ASTM) Standard G-36-94 [1]. This ASTM standard describes a procedure for conducting stress-corrosion cracking tests in boiling magnesium chloride (MgCl2) solution. Container sections in both the as-fabricated condition as well as the closure welded condition were evaluated. Significantly large residual stresses were observed in the bottom half of the as-fabricated container, a result of the base to can fabrication weld because through wall cracks were observed perpendicular to the weld. This observation indicates that regardless of the closure weld technique, sufficient residual stresses exist in the as-fabricated container to provide the stress necessary for stress corrosion cracking of the container, at the base fabrication weld. Additionally, sufficiently high residual stresses were observed in both the lid and the body of the GTAW as well as the laser closure welded containers. The stresses are oriented perpendicular to the closure weld in both the container lid and the container body. Although the boiling MgCl2 test is not a quantitative test, a comparison of the test results from the closure welds shows that there are noticeably more through wall cracks in the laser closure welded container than in the GTAW closure welded container

A survey of residual analysis and a new test of residual trend.

Science.gov (United States)

McDowell, J J; Calvin, Olivia L; Klapes, Bryan

2016-05-01

A survey of residual analysis in behavior-analytic research reveals that existing methods are problematic in one way or another. A new test for residual trends is proposed that avoids the problematic features of the existing methods. It entails fitting cubic polynomials to sets of residuals and comparing their effect sizes to those that would be expected if the sets of residuals were random. To this end, sampling distributions of effect sizes for fits of a cubic polynomial to random data were obtained by generating sets of random standardized residuals of various sizes, n. A cubic polynomial was then fitted to each set of residuals and its effect size was calculated. This yielded a sampling distribution of effect sizes for each n. To test for a residual trend in experimental data, the median effect size of cubic-polynomial fits to sets of experimental residuals can be compared to the median of the corresponding sampling distribution of effect sizes for random residuals using a sign test. An example from the literature, which entailed comparing mathematical and computational models of continuous choice, is used to illustrate the utility of the test. © 2016 Society for the Experimental Analysis of Behavior.

Residual stresses analysis of friction stir welding using one-way FSI simulation

International Nuclear Information System (INIS)

Kang, Sung Wook; Jang, Beom Seon; Song, Ha Cheol

2015-01-01

When certain mechanisms, such as plastic deformations and temperature gradients, occur and are released in a structure, stresses remain because of the shape of the structure and external constraints. These stresses are referred to as residual stresses. The base material locally expands during heating in the welding process. When the welding is completed and cooled to room temperature, the residual stresses are left at nearly the yield strength level. In the case of friction stir welding, the maximum temperature is 80% to 90% of the melting point of the materials. Thus, the residual stresses in the welding process are smaller than those in other fusion welding processes; these stresses have not been considered previously. However, friction stir welding residual stresses are sometimes measured at approximately 70% or above. These residual stresses significantly affect fatigue behavior and lifetime. The present study investigates the residual stress distributions in various welding conditions and shapes of friction stir welding. In addition, the asymmetric feature is considered in temperature and residual stress distribution. Heat transfer analysis is conducted using the commercial computational fluid dynamics program Fluent, and results are used in the finite element structural analysis with the ANSYS Multiphysics software. The calculated residual stresses are compared with experimental values using the X-ray diffraction method.

Pesticide residue analysis of soil, water, and grain of IPM basmati rice.

Science.gov (United States)

Arora, Sumitra; Mukherji, Irani; Kumar, Aman; Tanwar, R K

2014-12-01

The main aim of the present investigations was to compare the pesticide load in integrated pest management (IPM) with non-IPM crops of rice fields. The harvest samples of Basmati rice grain, soil, and irrigation water, from IPM and non-IPM field trials, at villages in northern India, were analyzed using multi-pesticide residue method. The field experiments were conducted for three consecutive years (2008-2011) for the successful validation of the modules, synthesized for Basmati rice, at these locations. Residues of tricyclazole, propiconazole, hexconazole, lambda cyhalothrin, pretilachlor chlorpyrifos, DDVP, carbendazim, and imidacloprid were analyzed from two locations, Dudhli village of Dehradun, Uttrakhand and Saboli and Aterna village of Sonepat, Haryana. The pesticide residues were observed below detectable limit (BDL) (water samples (2008-09). Residues of tricyclazole and carbendazim, analyzed from same locations, revealed pesticide residues as BDL (water samples (2009-2010). The residues of tricyclazole, propioconazole, chlorpyrifos, hexaconazole, pretilachlor, and λ-cyhalothrin were also found as BDL (water samples (<0.001-0.05 μg/L) (2010-2011).

Use of gypsum residues as a corrective for saline-sodic soil

Directory of Open Access Journals (Sweden)

Paulo Medeiros dos Santos

2014-03-01

Full Text Available One of the hugest problems faced by the civil construction sector is the final destination of residues, especially gypsum, which presents recycling restrictions. However, these residues present a high amount of calcium in their composition, and can be alternatively used for replacing mined gypsum as a saline-sodic soil corrective. This study aimed at evaluating the efficiency of gypsum residues from the civil construction, when compared to mined gypsum, for correcting a saline-sodic soil. A randomized blocks design was used, in a factorial arrangement consisting of two kinds of corrective (gypsum residue and mined gypsum and five leaching depths (0.5, 1.0, 1.5, 2.0 and 2.5 times the soil pores volume, with three replications. Electric conductivity, soluble cations and sodium adsorption ratio were evaluated in the soil saturation extract. The use of gypsum residue proved to be effective in leaching salts and soluble sodium in saline-sodic soil, and can be recommended as a calcium source for recovering from sodicity.

Recycling of porcelain tile polishing residue in portland cement: hydration efficiency.

Science.gov (United States)

Pelisser, Fernando; Steiner, Luiz Renato; Bernardin, Adriano Michael

2012-02-21

Ceramic tiles are widely used by the construction industry, and the manufacturing process of ceramic tiles generates as a major residue mud derived from the polishing step. This residue is too impure to be reused in the ceramic process and is usually discarded as waste in landfills. But the analysis of the particle size and concentration of silica of this residue shows a potential use in the manufacture of building materials based on portland cement. Tests were conducted on cement pastes and mortars using the addition of 10% and 20% (mass) of the residue. The results of compressive strength in mortars made up to 56 days showed a significant increase in compressive strength greater than 50%. The result of thermogravimetry shows that portlandite is consumed by the cement formed by the silica present in the residue in order to form calcium silicate hydrate and featuring a pozzolanic reaction. This effect improves the performance of cement, contributes to research and application of supplementary cementitious materials, and optimizes the use of portland cement, reducing the environmental impacts of carbon dioxide emissions from its production.

The origin of the residual conductivity of GaN films on ferroelectric materials

Science.gov (United States)

Lee, Kyoung-Keun; Cai, Zhuhua; Ziemer, Katherine; Doolittle, William Alan

2009-08-01

In this paper, the origin of the conductivity of GaN films grown on ferroelectric materials was investigated using XPS, AES, and XRD analysis tools. Depth profiles confirmed the existence of impurities in the GaN film originating from the substrates. Bonding energy analysis from XPS and AES verified that oxygen impurities from the substrates were the dominant origin of the conductivity of the GaN film. Furthermore, Ga-rich GaN films have a greater chance of enhancing diffusion of lithium oxide from the substrates, resulting in more substrate phase separation and a wider inter-mixed region confirmed by XRD. Therefore, the direct GaN film growth on ferroelectric materials causes impurity diffusion from the substrates, resulting in highly conductive GaN films. Future work needs to develop non-conductive buffer layers for impurity suppression in order to obtain highly resistive GaN films.

Initial contents of residue quality parameters predict effects of larger soil fauna on decomposition of contrasting quality residues

Directory of Open Access Journals (Sweden)

Ratikorn Sanghaw

2017-10-01

Full Text Available A 52-week decomposition study employing the soil larger fauna exclusion technique through litter bags of two mesh sizes (20 and 0.135 mm was conducted in a long-term (18 yr field experiment. Organic residues of contrasting quality of N, lignin (L, polyphenols (PP and cellulose (CL all in grams per kilogram: rice straw (RS: 4.5N, 22.2L, 3.9PP, 449CL, groundnut stover (GN: 21.2N, 71.4L, 8.1PP, 361CL, dipterocarp leaf litter (DP: 5.1N, 303L, 68.9PP, 271CL and tamarind leaf litter (TM: 11.6N, 190L, 27.7PP, 212CL were applied to soil annually to assess and predict soil larger fauna effects (LFE on decomposition based on the initial contents of the residue chemical constituents. Mass losses in all residues were not different under soil fauna inclusion and exclusion treatments during the early stage (up to week 4 after residue incorporation but became significantly higher under the inclusion than the exclusion treatments during the later stage (week 8 onwards. LFE were highest (2–51% under the resistant DP at most decomposition stages. During the early stage (weeks 1–4, both the initial contents of labile (N and CL and recalcitrant C, and recalcitrant C interaction with labile constituents of residues showed significant correlations (r = 0.64–0.90 with LFE. In the middle stage (week 16, LFE under resistant DP and TM had significant positive correlations with L, L + PP and L/CL. They were also affected by these quality parameters as shown by the multiple regression analysis. In the later stages (weeks 26–52, the L/CL ratio was the most prominent quality parameter affecting LFE. Keywords: Mesofauna and macrofauna, Microorganisms, Recalcitrant and labile compounds, Residue chemical composition, Tropical sandy soil

Conditioning of radioactive ash residue in a wave of solid-phase exothermal reactions

International Nuclear Information System (INIS)

Karlina, O.K.; Varlakova, G.A.; Ozhovan, M.I.; Tivanskij, V.M.; Dmitriev, S.A.

2001-01-01

The abilities for utilization of exothermic reaction heat in solid phase for conditioning the ash residue produced as a result of solid radioactive waste burning are analyzed. It is shown that the process of ash residue making monolithic with obtaining the glass-like finish product containing 50-60 mass % of ash residue which meets the requirements for solidified radioactive wastes may be realized without energy supplying from external heat sources. The conditioning is realized in a special crucible furnace-container designed not only for the process conducting but also for subsequent storage or disposal of the finish product [ru

Evaluation of residue-residue contact predictions in CASP9

KAUST Repository

Monastyrskyy, Bohdan; Fidelis, Krzysztof; Tramontano, Anna; Kryshtafovych, Andriy

2011-01-01

This work presents the results of the assessment of the intramolecular residue-residue contact predictions submitted to CASP9. The methodology for the assessment does not differ from that used in previous CASPs, with two basic evaluation measures

Analysis of Residual Stress and Deformation of Rolling Strengthen Crankshaft Fillet

Directory of Open Access Journals (Sweden)

Han Shaojun

2016-01-01

Full Text Available Based on the analysis of crankshaft fillet rolling process, used ANSYS finite element analysis software to conduct the elastic-plastic mechanical simulation of crankshaft rolling process, and gained the variation law of the residual stress and plastic deformation in the radial path of the fillet under different rolling laps and rolling pressure. Established the relationship between the rolling pressure and the plastic deformation and residual stress of the fillet, and provided theoretical support for the evaluation and detection of the crankshaft rolling quality.

Effect of mungbean residue and nitrogen levels on barley

International Nuclear Information System (INIS)

Jan, A.; Muhammad, Z.; Daur, I.; Khan, I.A.

2011-01-01

A field experiment was conducted to evaluate response of barley to mungbean residue (0, 10, 20 and 30 Mg ha/sup -1/), nitrogen levels (0, 25, 50 and 75 kg ha/sup -1/) and their interaction. Emergence m/sup -2/ (50), plant height (109 cm), leaf area tiller-1 (106 cm/sup 2/), lodging score (5.55), termites attack (3.4%), grains spike-1 (67), biological yield (12.80 Mg ha/sup -1/) and grain yield (2.32 Mg ha/sup -1/) were significantly (p=0.05) higher for 30 Mg ha/sup -1/ mungbean residue compared to other levels. Similarly plant height (110 cm), lodging score (5.29) and biological yield (13.75 Mg ha/sup -1/) were higher at 75 kg ha/sup -1/ N compared to other levels of N. Productive tillers m/sup -2/, grains spike/sup -1/, 1000 grain weight, grain yield and harvest index were optimum at 50 kg ha-1 N as compared to 75 kg ha/sup -1/ N that encouraged lodging. Interaction between residue and nitrogen indicated that 10 Mg residue and 50 kg N ha/sup -1/ is recommended to achieve maximum net return under comparable conditions. (author)

Determination of Pesticide Residues in Cannabis Smoke

OpenAIRE

Nicholas Sullivan; Sytze Elzinga; Jeffrey C. Raber

2013-01-01

The present study was conducted in order to quantify to what extent cannabis consumers may be exposed to pesticide and other chemical residues through inhaled mainstream cannabis smoke. Three different smoking devices were evaluated in order to provide a generalized data set representative of pesticide exposures possible for medical cannabis users. Three different pesticides, bifenthrin, diazinon, and permethrin, along with the plant growth regulator paclobutrazol, which are readily available...

Contaminant Leach Testing of Hanford Tank 241-C-104 Residual Waste

Energy Technology Data Exchange (ETDEWEB)

Cantrell, Kirk J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Snyder, Michelle M.V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-07-01

Leach testing of Tank C-104 residual waste was completed using batch and column experiments. Tank C-104 residual waste contains exceptionally high concentrations of uranium (i.e., as high as 115 mg/g or 11.5 wt.%). This study was conducted to provide data to develop contaminant release models for Tank C-104 residual waste and Tank C-104 residual waste that has been treated with lime to transform uranium in the waste to a highly insoluble calcium uranate (CaUO4) or similar phase. Three column leaching cases were investigated. In the first case, C-104 residual waste was leached with deionized water. In the second case, crushed grout was added to the column so that deionized water contacted the grout prior to contacting the waste. In the third case, lime was mixed in with the grout. Results of the column experiments demonstrate that addition of lime dramatically reduces the leachability of uranium from Tank C-104 residual waste. Initial indications suggest that CaUO4 or a similar highly insoluble calcium rich uranium phase forms as a result of the lime addition. Additional work is needed to definitively identify the uranium phases that occur in the as received waste and the waste after the lime treatment.

Dermal insecticide residues from birds inhabiting an orchard

Science.gov (United States)

Vyas, N.B.; Spann, J.W.; Hulse, C.S.; Gentry, S.; Borges, S.L.

2007-01-01

The US Environmental Protection Agency conducts risk assessments of insecticide applications to wild birds using a model that is limited to the dietary route of exposure. However, free-flying birds are also exposed to insecticides via the inhalation and dermal routes. We measured azinphos-methyl residues on the skin plus feathers and the feet of brown-headed cowbirds (Molothrus ater) in order to quantify dermal exposure to songbirds that entered and inhabited an apple (Malus x domestica) orchard following an insecticide application. Exposure to azinphos-methyl was measured by sampling birds from an aviary that was built around an apple tree. Birds sampled at 36 h and 7-day post-application were placed in the aviary within 1 h after the application whereas birds exposed for 3 days were released into the aviary 4-day post-application. Residues on vegetation and soil were also measured. Azinphos-methyl residues were detected from the skin plus feathers and the feet from all exposure periods. Our results underscore the importance of incorporating dermal exposure into avian pesticide risk assessments.

Characterization of residual radionuclide contamination within and around commercial nuclear power plants

International Nuclear Information System (INIS)

Robertson, D.E.; Abel, K.H.; Thomas, C.W.; Lepel, E.A.; Evans, J.C.; Thomas, W.V.; Carrick, L.C.; Leale, M.W.

1985-07-01

To provide a statistically valid data base for the residual radionuclide inventories in nuclear power stations, Pacific Northwest Laboratory (PNL) was contracted to conduct an extensive sampling and measurements program at a number of nuclear power plants. This paper summarizes the results of the radionuclide characterization studies conducted at seven nuclear power stations from a decommissioning assessment viewpoint

Feasibility of ultrasonic and eddy current methods for measurement of residual stress in shot peened metals

International Nuclear Information System (INIS)

Lavrentyev, Anton I.; Stucky, Paul A.; Veronesi, William A.

2000-01-01

Shot peening is a well-known method for extending the fatigue life of metal components by introducing compressive residual stresses near their surfaces. The capability to nondestructively evaluate the near surface residual stress would greatly aid the assurance of proper fatigue life in shot-peened components. This paper presents preliminary results from a feasibility study examining the use of ultrasonic and eddy current NDE methods for residual stress measurement in components where the stress has been introduced by shot peening. With an ultrasonic method, a variation of ultrasonic surface wave speed with shot peening intensity was measured. Near surface conductivity was measured by eddy current methods. Since the effective penetration depth of both methods employed is inversely related to the excitation frequency, by making measurements at different frequencies, each method has the potential to provide the stress-depth profile. Experiments were conducted on aluminum specimens (alloy 7075-T7351) peened within the Almen peening intensity range of 4C to 16C. The experimental results obtained demonstrate a correlation between peening intensity and Rayleigh wave velocity and between peening intensity and conductivity. The data suggests either of the methods may be suitable, with limitations, for detecting unsatisfactory levels of shot peening. Several factors were found to contribute to the measured responses: surface roughness, near surface plastic deformation (cold work) and residual stress. The contribution of each factor was studied experimentally. The feasibility of residual stress determination from the measured data is discussed

Measurement of residual stress in textured Al alloy by neutron diffraction method

International Nuclear Information System (INIS)

Okido, S.; Hayashi, M.; Tanaka, K.; Akiniwa, Y.; Minakawa, N.; Morii, Y.

1999-01-01

Residual stress generated in a shrunken aluminum alloy specimen, which was prepared for the round robin test conducted by VAMAS (Versailles Project on Advanced Materials and Standards) TWA-20 organized for the purpose of standardizing residual stress measurement methods, was evaluated by a neutron diffraction method. The main purpose of the round robin test was to assess the reproducibility of data obtained with the measurement facilities of the participants. The general standard of the Residual Stress Analyzer (RESA) constructed in the Japan Atomic Energy Research Institute was verified from the measured residual strains, which were equivalent to the values calculated by FEM and values measured by the research facilities in North America. Residual stress was calculated from residual strain in three perpendicular directions. The diffraction intensities were dependent on measurement directions since the prepared specimen possessed texture. Diffraction profiles in directions having a weak diffraction intensity caused an inaccurate evaluation of the residual stress. To solve this problem, a new method for evaluating residual stress with respect to diffraction plane dependency of the elastic constant was applied. The diffraction plane giving the highest intensity among 110, 200, and 220 diffraction was used to evaluate the residual strain in each of three directions. The residual strain obtained on the used diffraction plane was converted to the equivalent strain for the defined diffraction plane using the ratio of elastic constants of these two planes. The developed evaluation method achieved highly accurate measurement and remarkable efficiency in the measurement process. (author)

Decomposition of corn and soybean residues under field conditions and their role as inoculum source

Directory of Open Access Journals (Sweden)

E.M. Reis

2011-03-01

Full Text Available Necrotrophic parasites of above-ground plant parts survive saprophytically, between growing seasons in host crop residues. In an experiment conducted under field conditions, the time required in months for corn and soybean residues to be completely decomposed was quantified. Residues were laid on the soil surface to simulate no-till farming. Crop debris of the two plant species collected on the harvesting day cut into pieces of 5.0cm-long and a 200g mass was added to nylon mesh bags. At monthly intervals, bags were taken to the laboratory for weighing. Corn residues were decomposed within 37.0 months and those of soybean, within 34.5 months. Hw main necrotrophic fungi diagnosed in the corn residues were Colletotrichum gramicola, Diplodia spp. and Gibberella zeae, and those in soybeans residues were Cercospora kikuchii, Colletotrichum spp, Glomerella sp. and Phomopsis spp. Thus, those periods shoulb be observed in crop rotation aimed at to eliminating contaminated residues and, consequently, the inoculum from the cultivated area.

Effects of hydrated lime on radionuclides stabilization of Hanford tank residual waste.

Science.gov (United States)

Wang, Guohui; Um, Wooyong; Cantrell, Kirk J; Snyder, Michelle M V; Bowden, Mark E; Triplett, Mark B; Buck, Edgar C

2017-10-01

Chemical stabilization of tank residual waste is part of a Hanford Site tank closure strategy to reduce overall risk levels to human health and the environment. In this study, a set of column leaching experiments using tank C-104 residual waste were conducted to evaluate the leachability of uranium (U) and technetium (Tc) where grout and hydrated lime were applied as chemical stabilizing agents. The experiments were designed to simulate future scenarios where meteoric water infiltrates through the vadose zones into the interior of the tank filled with layers of grout or hydrated lime, and then contacts the residual waste. Effluent concentrations of U and Tc were monitored and compared among three different packing columns (waste only, waste + grout, and waste + grout + hydrated lime). Geochemical modeling of the effluent compositions was conducted to determine saturation indices of uranium solid phases that could control the solubility of uranium. The results indicate that addition of hydrated lime strongly stabilized the uranium through transforming uranium to a highly insoluble calcium uranate (CaUO 4 ) or similar phase, whereas no significant stabilization effect of grout or hydrated lime was observed on Tc leachability. The result implies that hydrated lime could be a great candidate for stabilizing Hanford tank residual wastes where uranium is one of the main concerns. Published by Elsevier Ltd.

Release of bound residues of atrazine from soils through autoclaving and gamma radiation sterilization

International Nuclear Information System (INIS)

Nakagawa, L.E.; Andréa, M.M.

1997-01-01

The sterilization methods are particularly important to study the influence of microorganisms on the pesticide dissipation in soils. This study, conducted in the laboratories of the Instituto Biológico of São Paulo in august 1996, tested the influence of two methods of soil sterilization - moist heat (autoclaving) and γ radiation - on the release of nonextractable or bound residues. It was studied, as example, bound residues of the herbicide atrazine in two types of soil (gley humic and dark red latosol). In the soil samples submitted to the moist heat sterilization, the recovery of the previously bound residues as reextractable residues was 5.6 and 5.9 times higher than in the control soils, not submitted to any sterilization process. Therefore, the method itself released the residues, indicating that the autoclaving is not the most appropriate method for studies on the influence of microorganisms on the release of bound residues. Otherwise, the γ radiation did not modify the residues recovery when compared to the controls. (author) [pt

Biological effects of plant residues with constrasting chemical compositions on plant and soil under humid tropical conditions

NARCIS (Netherlands)

Tian, G.

1992-01-01

A study on plant residues with contrasting chemical compositions was conducted under laboratory, growth chamber and humid tropical field conditions to understand the function of the soil fauna in the breakdown of plant residues, the cycling of nutrients, in particular nitrogen, and the

Rigid Residue Scan Simulations Systematically Reveal Residue Entropic Roles in Protein Allostery.

Directory of Open Access Journals (Sweden)

Robert Kalescky

2016-04-01

Full Text Available Intra-protein information is transmitted over distances via allosteric processes. This ubiquitous protein process allows for protein function changes due to ligand binding events. Understanding protein allostery is essential to understanding protein functions. In this study, allostery in the second PDZ domain (PDZ2 in the human PTP1E protein is examined as model system to advance a recently developed rigid residue scan method combining with configurational entropy calculation and principal component analysis. The contributions from individual residues to whole-protein dynamics and allostery were systematically assessed via rigid body simulations of both unbound and ligand-bound states of the protein. The entropic contributions of individual residues to whole-protein dynamics were evaluated based on covariance-based correlation analysis of all simulations. The changes of overall protein entropy when individual residues being held rigid support that the rigidity/flexibility equilibrium in protein structure is governed by the La Châtelier's principle of chemical equilibrium. Key residues of PDZ2 allostery were identified with good agreement with NMR studies of the same protein bound to the same peptide. On the other hand, the change of entropic contribution from each residue upon perturbation revealed intrinsic differences among all the residues. The quasi-harmonic and principal component analyses of simulations without rigid residue perturbation showed a coherent allosteric mode from unbound and bound states, respectively. The projection of simulations with rigid residue perturbation onto coherent allosteric modes demonstrated the intrinsic shifting of ensemble distributions supporting the population-shift theory of protein allostery. Overall, the study presented here provides a robust and systematic approach to estimate the contribution of individual residue internal motion to overall protein dynamics and allostery.

Differential regulation of cystic fibrosis transmembrane conductance regulator and Na+,K+ -ATPase in gills of striped bass, Morone saxatilis: effect of salinity and hormones

DEFF Research Database (Denmark)

Madsen, Steffen; Jensen, Lars Nørholm; Tipsmark, Christian Kølbaek

2007-01-01

-regulated kinase (ERK) 1/2 was stimulated by EGF but not affected by IGF-I. This study is the first to report a branchial EGF response and to demonstrate a functional ERK 1/2 pathway in the teleost gill. In conclusion, CFTR and Na(+),K(+) -ATPase are differentially regulated by salinity and hormones in gills...

Process for measuring the helium residual gas pressure and circuit for carrying out the process

International Nuclear Information System (INIS)

Schmidt, C.; Cesnak, L.

1983-01-01

In cryotechnic devices, the quality of the thermal insulation can be monitored by checking the pressure of the residual gas. A process is proposed in which a thin super-conducting wire or a superconducting layer acting as vacuum sensor has a heating pulse reaching the critical current applied to it, which produces a local normal conduction zone. The vacuum sensor has a measuring current of constant amount applied to it, which causes a voltage drop on its resistance during the time in which the normal conduction zone exists, the cooling time. The pressure of the residual gas is a function of the integral of the voltage drop and is measured by integrating the voltage during the cooling time. (orig./HP) [de

DERMAL AND MOUTHING TRANSFERS OF SURFACE RESIDUES MEASURED USING FLUORESCENCE IMAGING

Science.gov (United States)

To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and non-dietary ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to develop and test methods for measuring...

In-situ observation of dislocation and analysis of residual stresses by FEM/DDM modeling in water cavitation peening of pure titanium

International Nuclear Information System (INIS)

Ju, D Y; Han, B

2015-01-01

In this paper, in order to approach this problem, specimens of pure titanium were treated with WCP, and the subsequent changes in microstructure, residual stress, and surface morphologies were investigated as a function of WCP duration. The influence of water cavitation peening (WCP) treatment on the microstructure of pure titanium was investigated. A novel combined finite element and dislocation density method (FEM/DDM), proposed for predicting macro and micro residual stresses induced on the material subsurface treated with water cavitation peening, is also presented. A bilinear elastic-plastic finite element method was conducted to predict macro-residual stresses and a dislocation density method was conducted to predict micro-residual stresses. These approaches made possible the prediction of the magnitude and depth of residual stress fields in pure titanium. The effect of applied impact pressures on the residual stresses was also presented. The results of the FEM/DDM modeling were in good agreement with those of the experimental measurements. (paper)

On the Feasibility of Eddy Current Characterization of the Near-Surface Residual Stress Distribution in Nickel-Base Superalloys

International Nuclear Information System (INIS)

Blodgett, Mark P.; Nagy, Peter B.

2004-01-01

In light of its frequency-dependent penetration depth, the measurement of eddy current conductivity has been suggested as a possible means to allow the nondestructive evaluation of subsurface residual stresses in shot-peened specimens. This technique is based on the so-called electroelastic effect, i.e., the stress-dependence of the electrical conductivity. Unfortunately, the relatively small (∼1%) change in electrical conductivity caused by the presence of compressive residual stresses is often distorted, or even completely overshadowed, by the accompanying conductivity loss caused by cold work and surface roughness effects. Recently, it was observed that, in contrast with most other materials, shot-peened Waspaloy and IN100 specimens exhibit an apparent increase in electrical conductivity at increasing inspection frequencies. This observation by itself indicates that in these materials the measured conductivity change is probably dominated by residual stress effects, since both surface roughness and increased dislocation density are known to decrease rather than increase the conductivity and the presence of crystallographic texture does not affect the electrical conductivity of these materials, which crystallize in cubic symmetry. Our preliminary experiments indicate that probably there exists a unique 'window of opportunity' for eddy current NDE in nickel-base superalloys. We identified five major effects that contribute to this fortunate constellation of material properties, which will be reviewed in this presentation

Residual gas analysis

International Nuclear Information System (INIS)

Berecz, I.

1982-01-01

Determination of the residual gas composition in vacuum systems by a special mass spectrometric method was presented. The quadrupole mass spectrometer (QMS) and its application in thin film technology was discussed. Results, partial pressure versus time curves as well as the line spectra of the residual gases in case of the vaporization of a Ti-Pd-Au alloy were demonstrated together with the possible construction schemes of QMS residual gas analysers. (Sz.J.)

Eddy current spectroscopy for near-surface residual stress profiling in surface treated nonmagnetic engine alloys

Science.gov (United States)

Abu-Nabah, Bassam A.

Recent research results indicated that eddy current conductivity measurements can be exploited for nondestructive evaluation of near-surface residual stresses in surface-treated nickel-base superalloy components. Most of the previous experimental studies were conducted on highly peened (Almen 10-16A) specimens that exhibit harmful cold work in excess of 30% plastic strain. Such high level of cold work causes thermo-mechanical relaxation at relatively modest operational temperatures; therefore the obtained results were not directly relevant to engine manufacturers and end users. The main reason for choosing peening intensities in excess of recommended normal levels was that in low-conductivity engine alloys the eddy current penetration depth could not be forced below 0.2 mm without expanding the measurements above 10 MHz which is beyond the operational range of most commercial eddy current instruments. As for shot-peened components, it was initially felt that the residual stress effect was more difficult to separate from cold work, texture, and inhomogeneity effects in titanium alloys than in nickel-base superalloys. In addition, titanium alloys have almost 50% lower electric conductivity than nickel-base superalloys; therefore require proportionally higher inspection frequencies, which was not feasible until our recent breakthrough in instrument development. Our work has been focused on six main aspects of this continuing research, namely, (i) the development of an iterative inversion technique to better retrieve the depth-dependent conductivity profile from the measured frequency-dependent apparent eddy current conductivity (AECC), (ii) the extension of the frequency range up to 80 MHz to better capture the peak compressive residual stress in nickel-base superalloys using a new eddy current conductivity measuring system, which offers better reproducibility, accuracy and measurement speed than the previously used conventional systems, (iii) the lift-off effect on

Assessing the Availability of Wood Residues and Residue Markets in Virginia

OpenAIRE

Alderman, Delton R. Jr.

1998-01-01

A statewide mail survey of primary and secondary wood product manufacturers was undertaken to quantify the production and consumption of wood residues in Virginia. Two hundred and sixty-six wood product manufacturers responded to the study and they provided information on the production, consumption, markets, income or disposal costs, and disposal methods of wood residues. Hardwood and pine sawmills produce approximately 66 percent of Virginia's wood residues. Virginia's wood product man...

Mutational properties of amino acid residues: implications for evolvability of phosphorylatable residues

DEFF Research Database (Denmark)

Creixell, Pau; Schoof, Erwin M.; Tan, Chris Soon Heng

2012-01-01

in terms of their mutational activity. Moreover, we highlight the importance of the genetic code and physico-chemical properties of the amino acid residues as likely causes of these inequalities and uncover serine as a mutational hot spot. Finally, we explore the consequences that these different......; it is typically assumed that all amino acid residues are equally likely to mutate or to result from a mutation. Here, by reconstructing ancestral sequences and computing mutational probabilities for all the amino acid residues, we refute this assumption and show extensive inequalities between different residues...... mutational properties have on phosphorylation site evolution, showing that a higher degree of evolvability exists for phosphorylated threonine and, to a lesser extent, serine in comparison with tyrosine residues. As exemplified by the suppression of serine's mutational activity in phosphorylation sites, our...

Nitrogen mineralization from selected 15N-labelled crop residues and humus as affected by inorganic nitrogen

International Nuclear Information System (INIS)

Santos, J.A.

1987-01-01

The use of cover crops or crop residues as a source of N to succeeding crops has become a matter of increasing importance for economic and environmental reason. Greenhouse and field studies were conducted to determine the N contribution of four 15 N labelled crop residues, rye (Secale cereale L.), wheat (Triticum aestivum L.), crimson clover (Trifolium encarnatum L.), and hairy vetch (Vicia sativa L.), to successive crops and to evaluate the effect of different organic (ON) and inorganic N (IN) combinations on mineralization of the above residues. Total 15 N recovery from the residues ranged from 51% to 85% and 4% to 74% for the greenhouse and field studies, respectively

Square baler field test under different sugar cane crop residue conditions

Energy Technology Data Exchange (ETDEWEB)

Mello, Arthur Miola de; Ripoli, Tomaz Caetano Cannavan; Gadanha Junior, Casimiro [Escola Superior de Agricultura Luiz de Queiroz (ESALQ-USP), Piracicaba (Brazil). Dept. de Engenharia Rural], E-mail: ammello@esalq.usp.br; Ripoli, Marco Lorezzo Cunali [John Deere, Ribeirao Preto, SP (Brazil)

2008-07-01

The energy demand increase of the country allows the sugar cane business sector to be a major player in production and commercialization areas of electric energy using cogeneration powered by bagasse and sugar cane residues. The objective of the study was to evaluate some of the performance parameters of an Express 5040 baler, brand Nogueira, used to collect residues. The tests were conducted in a sugar cane mechanized harvest area. The baler was submitted to three different conditions of residues windrowing: 'in natura', under single and double raking operations. For all treatments soil sampling analyzes were done to find out ground homogeneity conditions were the test took place. The simple raking operation offered better conditions for the machine: Effective Capacity of 8.21 t.{sup h}-{sup 1} and 0.88 ha.h{sup -1}; average bale weight of 22.33 kg (SD=3.58, CV=16.01 %); costs of 7.45 R$.t{sup -1} of baled residue; 0.17 R$.fardo{sup -1} and 69.47 R$.ha{sup -1}. (author)

Leaching Behavior of Circulating Fluidised Bed MSWI Air Pollution Control Residue in Washing Process

Directory of Open Access Journals (Sweden)

Zhiliang Chen

2016-09-01

Full Text Available In this study, air pollution control (APC residue is conducted with water washing process to reduce its chloride content. A novel electrical conductivily (EC measurement method is proposed to monitor the dynamic change of chloride concentrations in leachate as well as the chloride content of the residue. The method equally applies to various washing processes with different washing time, liquid/solid ratio and washing frequency. The results show that washing effectively extracts chloride salts from APC residues, including those from circulating fluidized bed (CFB municipal solid waste incineration (MSWI. The most appropriate liquid/solid ratio and washing time in the first washing are found to be around 4 L water per kg of APC residue and 30 min, respectively, and washing twice is required to obtain maximum dissolution. The pH value is the major controlling factor of the heavy metals speciation in leachate, while chloride concentration also affects the speciation of Cd. Water washing causes no perceptible transfer of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs from the APC residue to leachate. The chloride concentration is strongly related with electrical conductivity (EC, as well as with the concentrations of calcium, sodium and potassium of washing water. Their regression analyses specify that soluble chloride salts and EC could act as an indirect indicator to monitor the change of chloride concentration and remaining chloride content, thus, contributing to the selection of the optimal washing conditions.

Estimation of average causal effect using the restricted mean residual lifetime as effect measure

DEFF Research Database (Denmark)

Mansourvar, Zahra; Martinussen, Torben

2017-01-01

with respect to their survival times. In observational studies where the factor of interest is not randomized, covariate adjustment is needed to take into account imbalances in confounding factors. In this article, we develop an estimator for the average causal treatment difference using the restricted mean...... residual lifetime as target parameter. We account for confounding factors using the Aalen additive hazards model. Large sample property of the proposed estimator is established and simulation studies are conducted in order to assess small sample performance of the resulting estimator. The method is also......Although mean residual lifetime is often of interest in biomedical studies, restricted mean residual lifetime must be considered in order to accommodate censoring. Differences in the restricted mean residual lifetime can be used as an appropriate quantity for comparing different treatment groups...

Evaluation of residue-residue contact prediction in CASP10

KAUST Repository

Monastyrskyy, Bohdan

2013-08-31

We present the results of the assessment of the intramolecular residue-residue contact predictions from 26 prediction groups participating in the 10th round of the CASP experiment. The most recently developed direct coupling analysis methods did not take part in the experiment likely because they require a very deep sequence alignment not available for any of the 114 CASP10 targets. The performance of contact prediction methods was evaluated with the measures used in previous CASPs (i.e., prediction accuracy and the difference between the distribution of the predicted contacts and that of all pairs of residues in the target protein), as well as new measures, such as the Matthews correlation coefficient, the area under the precision-recall curve and the ranks of the first correctly and incorrectly predicted contact. We also evaluated the ability to detect interdomain contacts and tested whether the difficulty of predicting contacts depends upon the protein length and the depth of the family sequence alignment. The analyses were carried out on the target domains for which structural homologs did not exist or were difficult to identify. The evaluation was performed for all types of contacts (short, medium, and long-range), with emphasis placed on long-range contacts, i.e. those involving residues separated by at least 24 residues along the sequence. The assessment suggests that the best CASP10 contact prediction methods perform at approximately the same level, and comparably to those participating in CASP9.

Agrochemical characterisation of the solid by-products and residues from the winery and distillery industry.

Science.gov (United States)

Bustamante, M A; Moral, R; Paredes, C; Pérez-Espinosa, A; Moreno-Caselles, J; Pérez-Murcia, M D

2008-01-01

The winery and distillery industry produces a great quantity of residues, whose management and disposal are environmental problems due to their seasonal character and some polluting characteristics. The main solid by-products and residues generated are grape stalk, grape pomace or marc, wine lee, exhausted grape marc and winery sludge. In this study, 87 samples of winery and distillery residues were collected from different Spanish wineries and distilleries. Electrical conductivity, pH, total organic matter, organic carbon, polyphenols and contents of plant nutrients and heavy metals were determined. The purpose of this research was to study the composition of these wastes and to find relationships in order to use easily analysable parameters to estimate their composition. In general, the winery and distillery residues showed low pH (mean values ranged from 3.8 to 6.8) and electrical conductivity values (1.62-6.15 dS m(-1)) and high organic matter (669-920 g kg(-1)) and macronutrient contents, especially in K (11.9-72.8 g kg(-1)). However, a notable polyphenol concentration (1.2-19.0 g kg(-1)) and low micronutrient and heavy metal contents were also observed, some of these properties being incompatible with agricultural requirements. Therefore, conditioning treatments are necessary prior to possible use of these wastes. In all wastes, significant correlations were found between easily determined parameters, such as pH, electrical conductivity and total organic matter, and most of the parameters studied. The regression models obtained are also discussed.

Proceedings of the 7. biennial residue-to-revenue residual wood conference 2007

International Nuclear Information System (INIS)

Raulin, J.

2007-01-01

This conference provided information on the highest and best use of residual wood, which is quickly becoming a valuable commodity. Issues concerning forest residues, sawmill wastes, agricultural residues and urban organic materials were discussed along with trends in Canadian surplus mill waste production. The evolving nature and technologies of the biomass business were highlighted with particular focus on how to generate energy and save money through the use of residual wood. Residual wood energy projects and developments in Canada, North America and Europe were outlined along with biomass development in relation to forest fires and insect disturbances. Cogeneration technologies using wood wastes for thermal heat, steam and electricity were also presented, along with transportation fuel technologies for the production of ethanol. It was noted that with the rising cost of energy, the forest industry is seeking energy solutions based on the use of residual wood. The range of economically practical residual wood solutions continues to grow as energy prices increase. The conference was attended by more than 200 delegates from the forest industry, suppliers and government representatives, to discuss policies and procedures currently in place. Industry investment is being stimulated by the potential for biofuels and biochemicals, as well as the co-operation between the forest and energy sectors. The conference featured 23 presentations, of which 12 have been catalogued separately for inclusion in this database. refs., tabs., figs

Estimation of selected residual antibiotics in muscle, kidney, liver, and egg of layer chicken

International Nuclear Information System (INIS)

Amjad, H.; Iqbal, J.; Naeem, M.

2006-01-01

The present studies were conducted for the estimation of quinolone residues in our local poultry products. The poultry products included muscle, kidney, liver and egg (yolk and white). The quinolones included in this study were, oxolonic acid, flumequine, enrofloxacin, and ciprofloxacin. An assessment of the variation of each analyte (quinolones antibiotic residues) in these products was made. A comparison was made among the analyte (quinolones) concentrations in different tissues/organs and their internationally permissible safer maximum residue limits (MRLS'). Infra Red spectra were used to detect the presence and identification of different quinolones. HPLC with ODS Column and U.V. detector was used for the quantification. (author)

A study on residues and degradation of 14C-phoxim in spring wheat plants and soil

International Nuclear Information System (INIS)

Zhu Shuxiu; Yin Lishang

1988-01-01

A potting experiment on residues and degradation of 14 C-phoxim in spring wheat plants and soil was conducted in 1984∼1986. Seed dressing or soil mixing and spraying with 14 C-phoxim had been done at sowing and seedling stage respectively. The radioactivities of samples were detected on the low background (3cpm) GM or Backman LS 7800 liquid scintillation counter. The transmission, dissociation and residues of 14 C-phoxim in spring wheat plants and soil were investigated. The amount of 14 C-phoxim residues in the grains was determined. The dissipation of the residues of 14 C-phoxim after the harvesting of spring wheat plants were discussed; the residues could be decomposed into 14 CO 2 , dissolved in evaporated liquid and throwed into air, or stored in soil

Airway Clearance Techniques (ACTs)

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Full Text Available ... and Resources Bioinformatics Tools for CF CFTR Antibodies Distribution Program CFTR Assays CF Foundation Biorepository CFTR Chemical ... or volunteering with your local chapter. DONATE YOUR TIME FIND A CLINICAL TRIAL FIND A LOCAL CHAPTER ...

Airway Clearance Techniques (ACTs)

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Full Text Available ... closer to a cure. Basics of the CFTR Protein Role of Genetics in CF CF Genetics The ... CF Foundation Biorepository CFTR Chemical Compound Program CFTR Protein Domains Patient Registry Data Requests Get Involved X ...

Airway Clearance Techniques (ACTs)

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Full Text Available ... closer to a cure. Basics of the CFTR Protein Role of Genetics in CF CF Genetics The ... Assays CFFT Biorepository CFTR Chemical Compound Program CFTR Protein Domains Patient Registry Data Requests Get Involved X ...

Effects of distance from center of a weld to fixed end on residual stress and stress intensity factor of a piping weld. Evaluation of SCC growth under residual stress field. Report 1

International Nuclear Information System (INIS)

Miyazaki, Katsumasa; Numata, Masanori; Saito, Koichi; Mochizuki, Masahito

2006-01-01

The fixed conditions of butt welds between straight pipe and valve or pump in the actual piping system are different from those of straight pipes. However, the effect of fixed condition on the residual stress and the stress intensity factor for evaluation of structural integrity of cracked piping was not clear. In this study, the finite element analyses were conducted by considering the differences in the distance from the center of weld to the fixed end L to clarify the effect of fixed condition on the residual stress and the stress intensity factor. For the 600 A piping, the axial residual stress distribution was not affected by the distance L. Furthermore, the stress intensity factor of circumferential crack under the residual stress field with fixed condition could be estimated by using the existing simplified solution for piping. (author)

Solid residues

International Nuclear Information System (INIS)

Mulder, E.; Duin, P.J. van; Grootenboer, G.J.

1995-01-01

A summary is presented of the many investigations that have been done on solid residues of atmospheric fluid bed combustion (AFBC). These residues are bed ash, cyclone ash and bag filter ash. Physical and chemical properties are discussed and then the various uses of residues (in fillers, bricks, gravel, and for recovery of aluminium) are summarised. Toxicological properties of fly ash and stack ash are discussed as are risks of pneumoconiosis for workers handling fly ash, and contamination of water by ashes. On the basis of present information it is concluded that risks to public health from exposure to emissions of coal fly ash from AFBC appear small or negligible as are health risk to workers in the coal fly ash processing industry. 35 refs., 5 figs., 12 tabs

Comparison of residual stress measurement in thin films using surface micromachining method

International Nuclear Information System (INIS)

He, Q.; Luo, Z.X.; Chen, X.Y.

2008-01-01

Conductive, dielectric, semiconducting, piezoelectric and ferroelectric thin films are extensively used for MEMS/NEMS applications. One of the important parameters of thin films is residual stress. The residual stress can seriously affect the properties, performance and long-term stability of the films. Excessive compressive or tensile stress results in buckling, cracking, splintering and sticking problems. Stress measurement techniques are therefore essential for both process development and process monitoring. Many suggestions for stress measurement in thin films have been made over the past several decades. This paper is concentrated on the in situ stress measurement using surface micromachining techniques to determine the residual stress. The authors review and compare several types of stress measurement methods including buckling technique, rotating technique, micro strain gauge and long-short beam strain sensor

AAV exploits subcellular stress associated with inflammation, endoplasmic reticulum expansion, and misfolded proteins in models of cystic fibrosis.

Directory of Open Access Journals (Sweden)

Jarrod S Johnson

2011-05-01

Full Text Available Barriers to infection act at multiple levels to prevent viruses, bacteria, and parasites from commandeering host cells for their own purposes. An intriguing hypothesis is that if a cell experiences stress, such as that elicited by inflammation, endoplasmic reticulum (ER expansion, or misfolded proteins, then subcellular barriers will be less effective at preventing viral infection. Here we have used models of cystic fibrosis (CF to test whether subcellular stress increases susceptibility to adeno-associated virus (AAV infection. In human airway epithelium cultured at an air/liquid interface, physiological conditions of subcellular stress and ER expansion were mimicked using supernatant from mucopurulent material derived from CF lungs. Using this inflammatory stimulus to recapitulate stress found in diseased airways, we demonstrated that AAV infection was significantly enhanced. Since over 90% of CF cases are associated with a misfolded variant of Cystic Fibrosis Transmembrane Conductance Regulator (ΔF508-CFTR, we then explored whether the presence of misfolded proteins could independently increase susceptibility to AAV infection. In these models, AAV was an order of magnitude more efficient at transducing cells expressing ΔF508-CFTR than in cells expressing wild-type CFTR. Rescue of misfolded ΔF508-CFTR under low temperature conditions restored viral transduction efficiency to that demonstrated in controls, suggesting effects related to protein misfolding were responsible for increasing susceptibility to infection. By testing other CFTR mutants, G551D, D572N, and 1410X, we have shown this phenomenon is common to other misfolded proteins and not related to loss of CFTR activity. The presence of misfolded proteins did not affect cell surface attachment of virus or influence expression levels from promoter transgene cassettes in plasmid transfection studies, indicating exploitation occurs at the level of virion trafficking or processing. Thus

Exchangeable basic cations and nitrogen distribution in soil as affected by crop residues and nitrogen

Directory of Open Access Journals (Sweden)

Ciro Antonio Rosolem

2011-06-01

Full Text Available In this work, a greenhouse experiment was conducted to study the effects of N fertilization and residues of pearl millet, black oats and oilseed radish on pH and Ca, Mg, K, NO3-, and NH4+ distribution within the profile of a Distroferric Red Latosol. The equivalent of 8 t ha-1 of plant residues were placed on soil surface. Lime was applied on the soil surface and nitrogen was applied over the straw at 0, 50, 100, and 150 mg kg-1, as ammonium nitrate. Corn was grown for 57 days. Calcium contents and pH in the soil profile were decreased by Pearl millet residue, while black oat and oilseed radish increased Ca contents and these effects are not related with Ca contents in residue tissue. However, the presence of plant residues increased nitrate, ammonium, and potassium contents in the deeper layers of the pots.

Cutoff Value of Pharyngeal Residue in Prognosis Prediction After Neuromuscular Electrical Stimulation Therapy for Dysphagia in Subacute Stroke Patients

OpenAIRE

Park, Jeong Mee; Yong, Sang Yeol; Kim, Ji Hyun; Jung, Hong Sun; Chang, Sei Jin; Kim, Ki Young; Kim, Hee

2014-01-01

Objective To determine the cutoff value of the pharyngeal residue for predicting reduction of aspiration, by measuring the residue of valleculae and pyriformis sinuses through videofluoroscopic swallowing studies (VFSS) after treatment with neuromuscular electrical stimulator (VitalStim) in stroke patients with dysphagia. Methods VFSS was conducted on first-time stroke patients before and after the VitalStim therapy. The results were analyzed for comparison of the pharyngeal residue in the im...

Scanning electron microscope/energy dispersive x ray analysis of impact residues in LDEF tray clamps

Science.gov (United States)

Bernhard, Ronald P.; Durin, Christian; Zolensky, Michael E.

1993-01-01

Detailed optical scanning of tray clamps is being conducted in the Facility for the Optical Inspection of Large Surfaces at JSC to locate and document impacts as small as 40 microns in diameter. Residues from selected impacts are then being characterized by Scanning Electron Microscopy/Energy Dispersive X-ray Analysis at CNES. Results from this analysis will be the initial step to classifying projectile residues into specific sources.

Airway Clearance Techniques (ACTs)

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Full Text Available ... THERAPIES RESEARCH CONSORTIUM Therapeutics Development Network TDN Coordinating Center Study Services Working With the TDN Tools and Resources Antimicrobial Tools and Resources Bioinformatics Tools for CF CFTR Antibodies Distribution Program CFTR Assays CFFT Biorepository CFTR Chemical Compound ...

Effect of Dodonaea viscosa Jacq. residues on growth and yield of ...

African Journals Online (AJOL)

This study was to evaluate the effect of Dodonaea viscosa Jacq. residues on mungbean (Vigna mungo L.Hepper) local cultivar. An experiment [using randomized complete block design (RCBD) design] with three replications was conducted in 2010. The trial comprised of four treatments such as mulching, incorporation into ...

Handling of Solid Residues

International Nuclear Information System (INIS)

Medina Bermudez, Clara Ines

1999-01-01

The topic of solid residues is specifically of great interest and concern for the authorities, institutions and community that identify in them a true threat against the human health and the atmosphere in the related with the aesthetic deterioration of the urban centers and of the natural landscape; in the proliferation of vectorial transmitters of illnesses and the effect on the biodiversity. Inside the wide spectrum of topics that they keep relationship with the environmental protection, the inadequate handling of solid residues and residues dangerous squatter an important line in the definition of political and practical environmentally sustainable. The industrial development and the population's growth have originated a continuous increase in the production of solid residues; of equal it forms, their composition day after day is more heterogeneous. The base for the good handling includes the appropriate intervention of the different stages of an integral administration of residues, which include the separation in the source, the gathering, the handling, the use, treatment, final disposition and the institutional organization of the administration. The topic of the dangerous residues generates more expectation. These residues understand from those of pathogen type that are generated in the establishments of health that of hospital attention, until those of combustible, inflammable type, explosive, radio-active, volatile, corrosive, reagent or toxic, associated to numerous industrial processes, common in our countries in development

Impact of toxic heavy metals and pesticide residues in herbal products

Directory of Open Access Journals (Sweden)

Nema S. Shaban

2016-03-01

Full Text Available Medicinal plants have a long history of use in therapy throughout the world and still make an important part of traditional medicine. The World Health Organization (WHO estimates that 65%–80% of the world's populations depend on the herbal products as their primary form of health care. This review is conducted to provide a general idea about chemical contaminants such as heavy metals and pesticide residues as major common contaminants of the herbal medicine, which impose serious health risks to human health. Additionally, we aim to provide different analytical methods for analysis of heavy metals and pesticide residues in the herbal medicine.

Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India

Directory of Open Access Journals (Sweden)

Korrapati Kotinagu

2015-04-01

Full Text Available Aim: The present study was conducted to find the organochlorine pesticide (OCP and organophosphorus pesticide (OPP residues in fodder and milk samples along Musi river belt, India. Materials and Methods: Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. Results: The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077. Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167. The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. Conclusion: The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX.

Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India.

Science.gov (United States)

Kotinagu, Korrapati; Krishnaiah, Nelapati

2015-04-01

The present study was conducted to find the organochlorine pesticide (OCP) and organophosphorus pesticide (OPP) residues in fodder and milk samples along Musi river belt, India. Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077). Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167). The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL) values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX.

Opportunities and Barriers to Resource Recovery and Recycling from Shredder Residue in the United States

Science.gov (United States)

Nayak, Naren; Apelian, Diran

2014-11-01

Shredder residue is the by-product remaining after ferrous and nonferrous metals have been recovered from the processing of vehicles, white goods, and peddler scrap. Shredder residue consists of glass, plastics, rubber, dirt, and small amounts of metal. It is estimated that 5-7 million tons of this shredder residue are landfilled each year in the United States. Technical advancements, coupled with European Union directives and the economic climate, have transformed the recycling of shredder residue in Europe. In the United States, however, regulatory controls and the cheap cost of landfill have worked against the advancement of recycling and recovery of this resource. The Argonne National Laboratory, which is funded by the U.S. Department of Energy, has investigated the effectiveness of recycling shredder residue into polymers. Other research has examined the use of shredder residue in waste-to-energy applications. To improve our ability to process and recycle shredder residue, an investigation of the regulatory, economic, and technological challenges was undertaken. The objective was to conduct a comprehensive review of work done to date, to document the composition of typical shredder output and to identify potential recoverable items (residual metals, plastics, rubber, foam, etc.). Along with uncovering potential new markets, the research would identify the technical, regulatory, and economic barriers to developing those markets.

Residual Strain Characteristics of Nickel-coated FBG Sensors

International Nuclear Information System (INIS)

Cho, Won-Jae; Hwang, A-Reum; Kim, Sang-Woo

2017-01-01

A metal-coated FBG (fiber Bragg grating) sensor has a memory effect, which can recall the maximum strains experienced by the structure. In this study, a nickel-coated FBG sensor was fabricated through electroless (i.e., chemical plating) and electroplating. A thickness of approximately 43 μm of a nickel layer was achieved. Then, we conducted cyclic loading tests for the fabricated nickel-coated FBG sensors to verify their capability to produce residual strains. The results revealed that the residual strain induced by the nickel coating linearly increased with an increase in the maximum strain experienced by the sensor. Therefore, we verified that a nickel-coated FBG sensor has a memory effect. The fabrication methods and the results of the cycle loading test will provide basic information and guidelines in the design of a nickel-coated FBG sensor when it is applied in the development of structural health monitoring techniques.

Residual Strain Characteristics of Nickel-coated FBG Sensors

Energy Technology Data Exchange (ETDEWEB)

Cho, Won-Jae; Hwang, A-Reum; Kim, Sang-Woo [Hankyong National Univ., Ansung (Korea, Republic of)

2017-07-15

A metal-coated FBG (fiber Bragg grating) sensor has a memory effect, which can recall the maximum strains experienced by the structure. In this study, a nickel-coated FBG sensor was fabricated through electroless (i.e., chemical plating) and electroplating. A thickness of approximately 43 μm of a nickel layer was achieved. Then, we conducted cyclic loading tests for the fabricated nickel-coated FBG sensors to verify their capability to produce residual strains. The results revealed that the residual strain induced by the nickel coating linearly increased with an increase in the maximum strain experienced by the sensor. Therefore, we verified that a nickel-coated FBG sensor has a memory effect. The fabrication methods and the results of the cycle loading test will provide basic information and guidelines in the design of a nickel-coated FBG sensor when it is applied in the development of structural health monitoring techniques.

Residual Isocyanates in Medical Devices and Products: A Qualitative and Quantitative Assessment

Directory of Open Access Journals (Sweden)

Gillian Franklin

2016-01-01

Full Text Available We conducted a pilot qualitative and quantitative assessment of residual isocyanates and their potential initial exposures in neonates, as little is known about their contact effect. After a neonatal intensive care unit (NICU stockroom inventory, polyurethane (PU and PU foam (PUF devices and products were qualitatively evaluated for residual isocyanates using Surface SWYPE ™ . Those containing isocyanates were quantitatively tested for methylene diphenyl diisocyanate (MDI species, using UPLC-UV-MS/MS method. Ten of 37 products and devices tested, indicated both free and bound residual surface isocyanates; PU/PUF pieces contained aromatic isocyanates; one product contained aliphatic isocyanates. Overall, quantified mean MDI concentrations were low (4,4‘-MDI = 0.52 to 140.1 pg/mg and (2,4‘-MDI = 0.01 to 4.48 pg/mg. The 4,4‘-MDI species had the highest measured concentration (280 pg/mg. Commonly used medical devices/products contain low, but measurable concentrations of residual isocyanates. Quantifying other isocyanate species and neonatal skin exposure to isocyanates from these devices and products requires further investigation.

Maize yield response to residual soil moisture In inland valley of ...

African Journals Online (AJOL)

Two sets of experiments were conducted in three replicates each on both upper and lower fringes of Minna inland valley, Niger State, Nigeria. While the upper fringe was subjected to surface irrigation the residual moisture in the lower fringe provided the maize crop with all water requirements from planting to maturity.

Airway Clearance Techniques (ACTs)

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Full Text Available ... Research We Fund Investing in Tomorrows Laboratory and Clinical Research We Fund CFTR Modulation Research We Fund CFTR ... Award Quality Care Awards Richard C Talamo Distinguished Clinical Achievement Award Robert J Beall Therapeutics ... Consortia CF Biomarker Consortium CFTR 3-D Structure ...

Drug Development Pipeline

Science.gov (United States)

... molecule that contains genetic instructions to make proteins. Delivery of CFTR-encoded mRNA would allow the lung cells to create normally functioning CFTR protein, regardless of an individual’s specific CFTR gene mutation. This drug is delivered via inhalation. Editas This program is ...

Spontaneous regression of residual low-grade cerebellar pilocytic astrocytomas in children

International Nuclear Information System (INIS)

Gunny, Roxana S.; Saunders, Dawn E.; Hayward, Richard D.; Phipps, Kim P.; Harding, Brian N.

2005-01-01

Cerebellar low-grade astrocytomas (CLGAs) of childhood are benign tumours and are usually curable by surgical resection alone or combined with adjuvant radiotherapy. To undertake a retrospective study of our children with CLGA to determine the optimum schedule for surveillance imaging following initial surgery. In this report we describe the phenomenon of spontaneous regression of residual tumour and discuss its prognostic significance regarding future imaging. A retrospective review was conducted of children treated for histologically proven CLGA at Great Ormond Street Hospital from 1988 to 1998. Of 83 children with CLGA identified, 13 (15.7%) had incomplete resections. Two children with large residual tumours associated with persistent symptoms underwent additional treatment. Eleven children were followed by surveillance imaging alone for a mean of 6.83 years (range 2-13.25 years). Spontaneous tumour regression was seen in 5 (45.5%) of the 11 children. There were no differences in age, gender, symptomatology, histological grade or Ki-67 fractions between those with spontaneous tumour regression and those with progression. There was a non-significant trend that larger volume residual tumours progressed. Residual tumour followed by surveillance imaging may either regress or progress. For children with residual disease we recommend surveillance imaging every 6 months for the first 2 years, every year for years 3, 4 and 5, then every second year if residual tumour is still present 5 years after initial surgery. This would detect not only progressive or recurrent disease, but also spontaneous regression which can occur later than disease progression. (orig.)

Superior thermal conductivity in suspended bilayer hexagonal boron nitride

Science.gov (United States)

Wang, Chengru; Guo, Jie; Dong, Lan; Aiyiti, Adili; Xu, Xiangfan; Li, Baowen

2016-01-01

We reported the basal-plane thermal conductivity in exfoliated bilayer hexagonal boron nitride h-BN that was measured using suspended prepatterned microstructures. The h-BN sample suitable for thermal measurements was fabricated by dry-transfer method, whose sample quality, due to less polymer residues on surfaces, is believed to be superior to that of PMMA-mediated samples. The measured room temperature thermal conductivity is around 484 Wm−1K−1(+141 Wm−1K−1/ −24 Wm−1K−1) which exceeds that in bulk h-BN, providing experimental observation of the thickness-dependent thermal conductivity in suspended few-layer h-BN. PMID:27142571

2018-03-29T01:34:18Z https://www.ajol.info/index.php/all/oai oai:ojs ...

African Journals Online (AJOL)

The common ones such as Y-chromosome microdeletions in the azoospermia factor (AZF) locus, Klinifelter syndrome 47XXY and Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations leading to congenital absence of the vas deferens (CAVD) are discussed. Other less common causes include ...

PENETAPAN RESIDU DAN PERKIRAAN PENETAPAN BATAS MAKSIMUM RESIDU (BMR ORGANOKLORIN PADA SIMPLISIA

Directory of Open Access Journals (Sweden)

Ani Isnawati

2012-10-01

Full Text Available Penggunaaan bahan obat tradisional (simplisia untuk skala industri dan peningkatan produksi tanaman obat dalam skala besar menjadi tidak ekonomis tanpa pestisida. Disatu sisi penggunaan pestisida dapat menguntungkan yaitu menyebabkan toksis pada hama namun disisi lain toksisitas dapat terjadi juga pada manusia, sehingga residu pestisida dalam tanaman obat yang dikonsumsi dalam jangka panjang akan merugikan kesehatan. Batas maksimum Residu (BMR pestisida dalam simplisia baik di Indonesia maupun di negara lain belum ditetapkan. Sehingga untuk itu untuk mengetahui adanya residu pestisida jenis organoklorin yang telah dilarang penggunaannya melalui Permentan No.434.1/kpts/TP.270/7/2001 dan untuk mengetahui batas keamanannya, maka perlu dilakukan penetapan residu organoklorin dalam simplisia dan menetapkan batas keamanan berdasarkan perhitungan secara teoritis. Pengujian residu dilakukan terhadap golongan pestisida organoklorin pada 4 jenis simplisia (daun wungu (Graptophyllum pictum (L Grifl, daun sambiloto Andrographis paniculata Ness, herba pegagan (Centella  asiatica (L Urban, daun tempuyung (Sonchus arvensis (L yang berasal dari 3 lokasi penanaman, yaitu : perkebunan Tanaman Obat Manako (Jawa Barat, Balai Penelitian Tanaman Obat Tawangmangu (BPTO di Jawa Tengah dan Perkebunan Tanaman Obat Purwodadi (Jawa Timur. Pemeriksaan residu pestisida organoklorin menggunakan kromatografi gas dan perhitungan batas keamanan dihitung dengan adanya nilai ADI (Acceptable daily intake yang telah ditetapkan bersama antara JAO dan WHO serta perkiraan banyaknya konsumsi simplisia. Hasil Pengujian residu pestisida organoklorin diperoleh bahwa simplisia daun Wungu (Tawangmangu mengandung residu lindan dengan kadar 0,24 mg/kg, pegagan (Purwodadi, mengandung lindan 0,36 mg/kg dan aldrin 0,31 mg/kg serta pegagan (Manako mengandung heptaklor 0,15 mg/kg dan op-DDE 0,11 mg/kg. Adapun penghitungan BMR heptaklor dan lindan secara teoritis dengan asumsi rata

Residual magnetic field in rotary machines; Campo magnetico residual en maquinas rotatorias

Energy Technology Data Exchange (ETDEWEB)

Gonzalez V, Esteban A; Apanco R, Marcelino [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

2007-07-01

The residual magnetism is a phenomenon in which the magnetic dipoles of a substance are oriented in a certain degree. On the other hand, when internal forces exist capable of aligning elementary magnetic dipoles of a material, a permanent magnet is obtained. Just as in a conductor or in a material, in the elements of a rotary electrical machine magnetic fields can be induced that produce a residual magnetism or magnetization. In the rotary electrical machines, the magnetization phenomenon causes serious problems, such as the generation of induced currents that propitiate the mechanical wear in bearings, collars, trunnions and inclusive in the shaft, by effects known as pitting, frosting and spark tracks, as well as erroneous readings in vibration and temperature sensors, that in some cases can cause the shut down of the machine. In this article are presented the general concepts on the residual magnetism in rotary electrical machines, the causes that originate it and the problems that arises, as well as the demagnetization of the components that have residual magnetic field. The results obtained by the area of Electrical Equipment of the Instituto de Investigaciones Electricas are revised, during the execution of activities related to the measurement and elimination of the residual magnetic field in rotary electrical machines. [Spanish] El magnetismo residual es un fenomeno en el que los dipolos magneticos de una sustancia se encuentran orientados en un grado determinado. Por otro lado, cuando existen fuerzas internas capaces de alinear los dipolos magneticos elementales de un material, se tiene un iman permanente. Al igual que en un conductor o un material, en los elementos de una maquina electrica rotatoria se pueden inducir campos magneticos que producen un magnetismo residual o magnetizacion. En las maquinas electricas rotatorias, el fenomeno de magnetizacion causa graves problemas, como la generacion de corrientes inducidas que propician el desgaste mecanico

Sphingosine-1-Phosphate Signaling Regulates Myogenic Responsiveness in Human Resistance Arteries.

Directory of Open Access Journals (Sweden)

Sonya Hui

Full Text Available We recently identified sphingosine-1-phosphate (S1P signaling and the cystic fibrosis transmembrane conductance regulator (CFTR as prominent regulators of myogenic responsiveness in rodent resistance arteries. However, since rodent models frequently exhibit limitations with respect to human applicability, translation is necessary to validate the relevance of this signaling network for clinical application. We therefore investigated the significance of these regulatory elements in human mesenteric and skeletal muscle resistance arteries. Mesenteric and skeletal muscle resistance arteries were isolated from patient tissue specimens collected during colonic or cardiac bypass surgery. Pressure myography assessments confirmed endothelial integrity, as well as stable phenylephrine and myogenic responses. Both human mesenteric and skeletal muscle resistance arteries (i express critical S1P signaling elements, (ii constrict in response to S1P and (iii lose myogenic responsiveness following S1P receptor antagonism (JTE013. However, while human mesenteric arteries express CFTR, human skeletal muscle resistance arteries do not express detectable levels of CFTR protein. Consequently, modulating CFTR activity enhances myogenic responsiveness only in human mesenteric resistance arteries. We conclude that human mesenteric and skeletal muscle resistance arteries are a reliable and consistent model for translational studies. We demonstrate that the core elements of an S1P-dependent signaling network translate to human mesenteric resistance arteries. Clear species and vascular bed variations are evident, reinforcing the critical need for further translational study.

Inhibition by TNF-alpha and IL-4 of cationic lipid mediated gene transfer in cystic fibrosis tracheal gland cells.

Science.gov (United States)

Bastonero, Sonia; Gargouri, Myriem; Ortiou, Sandrine; Guéant, Jean-Louis; Merten, Marc D

2005-11-01

In vivo, tracheal gland serous cells highly express the cystic fibrosis transmembrane conductance regulator (cftr) gene. This gene is mutated in the lethal monogenic disease cystic fibrosis (CF). Clinical trials in which the human CFTR cDNA was delivered to the respiratory epithelia of CF patients have resulted in weak and transient gene expression. As CF is characterized by mucus inspissation, airway infection, and severe inflammation, we tested the hypothesis that inflammation and especially two cytokines involved in the Th1/Th2 inflammatory response, interleukin 4 (IL-4) and TNFalpha, could inhibit gene transfer efficiency using a model of human CF tracheal gland cells (CF-KM4) and Lipofectamine reagent as a transfection reagent. The specific secretory defects of CF-KM4 cells were corrected by Lipofectamine-mediated human CFTR gene transfer. However, this was altered when cells were pre-treated with IL-4 and TNFalpha. Inhibition of luciferase reporter gene expression by IL-4 and TNFalpha pre-treated CF-KM4 cells was measured by activity and real-time RT-PCR. Both cytokines induced similar and synergistic inhibition of transgene expression and activity. This cytokine-mediated inhibition could be prevented by anti-inflammatory agents such as glucocorticoids but not by non-steroidal (NSAI) agents. This data suggests that an inflammatory context generated by IL-4 and TNFalpha can inhibit human CFTR gene transfer in CF tracheal gland cells and that glucocorticoids may have a protecting action. Copyright (c) 2005 John Wiley & Sons, Ltd.

Cumulative effects of white clover residues on the changes in soil ...

African Journals Online (AJOL)

White clover grows naturally all over the Himalayan regions including the hilly areas of the state of Azad Jammu and Kashmir (AJK), Pakistan. This study was conducted to investigate the effects of white clover residues alone or in combination with phosphorus (P) fertilizer on maize (Zea mays L.) yield, nutrient uptake and ...

N- and C-alkylation of seven-membered iminosugars generates potent glucocerebrosidase inhibitors and F508del-CFTR correctors.

Science.gov (United States)

Désiré, J; Mondon, M; Fontelle, N; Nakagawa, S; Hirokami, Y; Adachi, I; Iwaki, R; Fleet, G W J; Alonzi, D S; Twigg, G; Butters, T D; Bertrand, J; Cendret, V; Becq, F; Norez, C; Marrot, J; Kato, A; Blériot, Y

2014-11-28

The glycosidase inhibitory properties of synthetic C-alkyl and N-alkyl six-membered iminosugars have been extensively studied leading to therapeutic candidates. The related seven-membered iminocyclitols have been less examined despite the report of promising structures. Using an in house ring enlargement/C-alkylation as well as cross-metathesis methodologies as the key steps, we have undertaken the synthesis and biological evaluation of a library of fourteen 2C- and eight N-alkyl tetrahydroxylated azepanes starting from an easily available glucopyranose-derived azidolactol. Four, six, nine and twelve carbon atom alkyl chains have been introduced. The study of two distinct D-gluco and L-ido stereochemistries for the tetrol pattern as well as R and S configurations for the C-2 carbon bearing the C-alkyl chain is reported. We observed that C-alkylation of the L-ido tetrahydroxylated azepane converts it from an α-L-fucosidase to a β-glucosidase and β-galactosidase inhibitor while N-alkylation of the D-gluco iminosugar significantly improves its inhibition profile leading to potent β-glucosidase, β-galactosidase, α-L-rhamnosidase and β-glucuronidase inhibitors whatever the stereochemistry of the alkyl chain. Interestingly, the N-alkyl chain length usually parallels the azepane inhibitor potency as exemplified by the identification of a potent glucocerebrosidase inhibitor (Ki 1 μM) bearing a twelve carbon atom chain. Additionally, several C-alkyl azepanes demonstrated promising F508del-CFTR correction unlike the parent tetrahydroxyazepanes. None of the C-alkyl and N-alkyl azepanes did inhibit ER α-glucosidases I or II.

Use of Residual Solids from Pulp and Paper Mills for Enhancing Strength and Durability of Ready-Mixed Concrete

Energy Technology Data Exchange (ETDEWEB)

Tarun R. Naik; Yoon-moon Chun; Rudolph N. Kraus

2003-09-18

This research was conducted to establish mixture proportioning and production technologies for ready-mixed concrete containing pulp and paper mill residual solids and to study technical, economical, and performance benefits of using the residual solids in the concrete. Fibrous residuals generated from pulp and paper mills were used, and concrete mixture proportions and productions technologies were first optimized under controlled laboratory conditions. Based on the mixture proportions established in the laboratory, prototype field concrete mixtures were manufactured at a ready-mixed concrete plant. Afterward, a field construction demonstration was held to demonstrate the production and placement of structural-grade cold-weather-resistant concrete containing residual solids.

Non-isothermal kinetic studies on co-processing of olive residue and polypropylene

International Nuclear Information System (INIS)

Aboulkas, A.; El Harfi, K.; El Bouadili, A.

2008-01-01

Co-processing of olive residue with polypropylene was performed in a thermogravimetric analyzer (TGA) reaction system in a nitrogen atmosphere with a view to comparing the process of the mixture with those of the individual components. Experiments were conducted at different heating rates of 2, 10, 20 and 50 K min -1 in the temperature range of 300-975 K based on the results obtained, three thermal stages were identified during the thermal degradation. The first two were dominated by olive residue pyrolysis, while the third was linked to polypropylene pyrolysis, which occurred at much higher temperatures. Discrepancies between the experimental and calculated TG/DTG profiles were considered as a measurement of the extent of interactions occurring on co-pyrolysis. The maximum degradation temperature of each component in the mixture was higher than those of the individual components alone; thus, an increase in thermal stability was expected. The kinetic processing of thermogravimetric data was conducted using the Friedman method

Dilute alkali and hydrogen peroxide treatment of microwave liquefied rape straw residue for the extraction of cellulose nanocrystals

Science.gov (United States)

Xingyan Huang; Cornelis F. De Hoop; Feng Li; Jiulong Xie; Chung-Yun Hse; Jinqiu Qi; Yongze Jiang; Yuzhu Chen

2017-01-01

Microwave-assisted liquefaction of rape straw in methanol was conducted to collect the liquefied residues for the extraction of cellulose nanocrystals (CNCs).The liquefied residue with content of 23.44% from 180∘C/7.5 min was used to fibrillate CNCs with dilute alkali (2% NaOH) and hydrogen peroxide (5% H2O2...

Mapping allostery through computational glycine scanning and correlation analysis of residue-residue contacts.

Science.gov (United States)

Johnson, Quentin R; Lindsay, Richard J; Nellas, Ricky B; Fernandez, Elias J; Shen, Tongye

2015-02-24

Understanding allosteric mechanisms is essential for the physical control of molecular switches and downstream cellular responses. However, it is difficult to decode essential allosteric motions in a high-throughput scheme. A general two-pronged approach to performing automatic data reduction of simulation trajectories is presented here. The first step involves coarse-graining and identifying the most dynamic residue-residue contacts. The second step is performing principal component analysis of these contacts and extracting the large-scale collective motions expressed via these residue-residue contacts. We demonstrated the method using a protein complex of nuclear receptors. Using atomistic modeling and simulation, we examined the protein complex and a set of 18 glycine point mutations of residues that constitute the binding pocket of the ligand effector. The important motions that are responsible for the allostery are reported. In contrast to conventional induced-fit and lock-and-key binding mechanisms, a novel "frustrated-fit" binding mechanism of RXR for allosteric control was revealed.

Test and Numerical Analysis for Penetration Residual Velocity of Bullet Considering Failure Strain Uncertainty of Composite Plates

Energy Technology Data Exchange (ETDEWEB)

Cha, Myungseok; Lee, Minhyung [Sejong Univ., Sejong (Korea, Republic of)

2016-03-15

The ballistic performance data of composite materials is distributed due to material inhomogeneity. In this paper, the uncertainty in residual velocity is obtained experimentally, and a method of predicting it is established numerically for the high-speed impact of a bullet into laminated composites. First, the failure strain distribution was obtained by conducting a tensile test using 10 specimens. Next, a ballistic impact test was carried out for the impact of a fragment-simulating projectile (FSP) bullet with 4ply ([0/90]s) and 8ply ([0/90/0/90]s) glass fiber reinforced plastic (GFRP) plates. Eighteen shots were made at the same impact velocity and the residual velocities were obtained. Finally, simulations were conducted to predict the residual velocities by using the failure strain distributions that were obtained from the tensile test. For this simulation, two impact velocities were chosen at 411.7m/s (4ply) and 592.5m/s (8ply). The simulation results show that the predicted residual velocities are in close agreement with test results. Additionally, the modeling of a composite plate with layered solid elements requires less calculation time than modeling with solid elements.

Characterization of protein and carbohydrate mid-IR spectral features in crop residues

Science.gov (United States)

Xin, Hangshu; Zhang, Yonggen; Wang, Mingjun; Li, Zhongyu; Wang, Zhibo; Yu, Peiqiang

2014-08-01

To the best of our knowledge, a few studies have been conducted on inherent structure spectral traits related to biopolymers of crop residues. The objective of this study was to characterize protein and carbohydrate structure spectral features of three field crop residues (rice straw, wheat straw and millet straw) in comparison with two crop vines (peanut vine and pea vine) by using Fourier transform infrared spectroscopy (FTIR) technique with attenuated total reflectance (ATR). Also, multivariate analyses were performed on spectral data sets within the regions mainly related to protein and carbohydrate in this study. The results showed that spectral differences existed in mid-IR peak intensities that are mainly related to protein and carbohydrate among these crop residue samples. With regard to protein spectral profile, peanut vine showed the greatest mid-IR band intensities that are related to protein amide and protein secondary structures, followed by pea vine and the rest three field crop straws. The crop vines had 48-134% higher spectral band intensity than the grain straws in spectral features associated with protein. Similar trends were also found in the bands that are mainly related to structural carbohydrates (such as cellulosic compounds). However, the field crop residues had higher peak intensity in total carbohydrates region than the crop vines. Furthermore, spectral ratios varied among the residue samples, indicating that these five crop residues had different internal structural conformation. However, multivariate spectral analyses showed that structural similarities still exhibited among crop residues in the regions associated with protein biopolymers and carbohydrate. Further study is needed to find out whether there is any relationship between spectroscopic information and nutrition supply in various kinds of crop residue when fed to animals.

Characterization Report on Sand, Slag, and Crucible Residues and on Fluoride Residues

International Nuclear Information System (INIS)

Murray, A.M.

1999-01-01

This paper reports on the chemical characterization of the sand, slag, and crucible (SS and C) residues and the fluoride residues that may be shipped from the Rocky Flats Environmental Technology Site (RFETS) to Savannah River Site (SRS)

Determination of Activated Carbon Residual Life using a Microwave Cavity Resonator

International Nuclear Information System (INIS)

Mason, A; Wylie, S; Shaw, A; Al-Shamma'a, A I; Thomas, A; Keele, H

2011-01-01

This paper presents the continuation of work conducted jointly between Dstl and LJMU. This unique body of work has been, largely, concerned with detecting the residual life of high performance filter materials using electromagnetic (EM) waves within a resonant cavity. Past work has considered both HEPA [1] and ASZM-TEDA[2] activated carbon filter materials. This paper continues the later work, considering the response of ASZM-TEDA activated carbon through the co-ageing of two distinct batches of the material. The paper briefly introduces activated carbon, discusses theory relevant to the work and the methodology used for investigation. A comprehensive set of results is included which seek to validate this technique for determining the residual lifespan of activated carbon.

Steel research using neutron beam techniques. In-situ neutron diffraction, small-angle neutron scattering and residual stress analysis

International Nuclear Information System (INIS)

Sueyoshi, Hitoshi; Ishikawa, Nobuyuki; Yamada, Katsumi; Sato, Kaoru; Nakagaito, Tatsuya; Matsuda, Hiroshi; Arakaki, Yu; Tomota, Yo

2014-01-01

Recently, the neutron beam techniques have been applied for steel researches and industrial applications. In particular, the neutron diffraction is a powerful non-destructive method that can analyze phase transformation and residual stress inside the steel. The small-angle neutron scattering is also an effective method for the quantitative evaluation of microstructures inside the steel. In this study, in-situ neutron diffraction measurements during tensile test and heat treatment were conducted in order to investigate the deformation and transformation behaviors of TRIP steels. The small-angle neutron scattering measurements of TRIP steels were also conducted. Then, the neutron diffraction analysis was conducted on the high strength steel weld joint in order to investigate the effect of the residual stress distribution on the weld cracking. (author)

Cystic fibrosis transmembrane regulator haplotypes in households of patients with cystic fibrosis.

Science.gov (United States)

Furgeri, Daniela Tenório; Marson, Fernando Augusto Lima; Correia, Cyntia Arivabeni Araújo; Ribeiro, José Dirceu; Bertuzzo, Carmen Sílvia

2018-01-30

Nearly 2000 mutations in the cystic fibrosis transmembrane regulator (CFTR) gene have been reported. The F508del mutation occurs in approximately 50-65% of patients with cystic fibrosis (CF). However, molecular diagnosis is not always possible. Therefore, silent polymorphisms can be used to label the mutant allele in households of patients with CF. To verify the haplotypes of four polymorphisms at the CFTR locus in households of patients with CF for pre-fertilization, pre-implantation, and prenatal indirect mutation diagnosis to provide better genetic counseling for families and patients with CF and to associate the genotypes/haplotypes with the F508del mutation screening. GATT polymorphism analysis was performed using direct polymerase chain reaction amplification, and the MP6-D9, TUB09 and TUB18 polymorphism analyses were performed using restriction fragment length polymorphism. Nine haplotypes were found in 37 CFTR alleles, and of those, 24 were linked with the F508del mutation and 13 with other CFTR mutations. The 6 (GATT), C (MP6-D9), G (TUB09), and C (TUB18) haplotypes showed the highest prevalence (48%) of the mutant CFTR allele and were linked to the F508del mutation (64%). In 43% of households analyzed, at least one informative polymorphism can be used for the indirect diagnostic test. CFTR polymorphisms are genetic markers that are useful for identifying the mutant CFTR alleles in households of patients with CF when it is not possible to establish the complete CFTR genotype. Moreover, the polymorphisms can be used for indirect CFTR mutation identification in cases of pre-fertilization, pre-implantation and prenatal analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of Cutting Edge Microgeometry on Residual Stress in Orthogonal Cutting of Inconel 718 by FEM.

Science.gov (United States)

Shen, Qi; Liu, Zhanqiang; Hua, Yang; Zhao, Jinfu; Lv, Woyun; Mohsan, Aziz Ul Hassan

2018-06-14

Service performance of components such as fatigue life are dramatically influenced by the machined surface and subsurface residual stresses. This paper aims at achieving a better understanding of the influence of cutting edge microgeometry on machined surface residual stresses during orthogonal dry cutting of Inconel 718. Numerical and experimental investigations have been conducted in this research. The cutting edge microgeometry factors of average cutting edge radius S¯, form-factor K , and chamfer were investigated. An increasing trend for the magnitudes of both tensile and compressive residual stresses was observed by using larger S¯ or introducing a chamfer on the cutting edges. The ploughing depth has been predicted based on the stagnation zone. The increase of ploughing depth means that more material was ironed on the workpiece subsurface, which resulted in an increase in the compressive residual stress. The thermal loads were leading factors that affected the surface tensile residual stress. For the unsymmetrical honed cutting edge with K = 2, the friction between tool and workpiece and tensile residual stress tended to be high, while for the unsymmetrical honed cutting edge with K = 0.5, the high ploughing depth led to a higher compressive residual stress. This paper provides guidance for regulating machine-induced residual stress by edge preparation.

Antimicrobial residues in tissues and eggs of laying hens at Chittagong, Bangladesh

Directory of Open Access Journals (Sweden)

Ariful Islam

2016-12-01

Full Text Available Aim: Antimicrobial residue in animal food products is an important index of food safety. Antimicrobial residues could result from chemotherapeutic or chemoprophylactic use of drugs in food animals. This occurrence of residue in animal food products has received enormous worldwide attention from some local, international, and public health agencies. A crosssectional study was conducted from July to December 2009 to detect the antibiotic residues in tissues and eggs of laying hens at Chittagong of Bangladesh. Materials and Methods: Microbial inhibition test (MIT and thin layer chromatography (TLC methods were used to detect antibacterial residues in poultry tissues (liver, kidney, breast, and thigh muscles and eggs. The bacteria and pH of the MIT method were as follows: Bacillus subtilis on test agar medium with a pH of 7.2, Bacillus cereus with a pH of 6.0, and Escherichia coli at pH with an 8.0. Results: The overall prevalence of antibiotic residues detected by MIT was 64% in liver, 63% in kidney, 56% in breast muscle, 50% in thigh muscle, and 60% in eggs. There was significant variation in results between MIT and TLC (p<0.05. Tetracycline residues were found in 48% in liver, 24% in kidneys, 20% in thigh muscles, 26% in breast muscles, and 36% in eggs. Ciprofloxacin residues were found 46% in liver, 42% in kidneys, 34% in thigh muscles, 30% in breast muscles, and 30% in eggs. Enrofloxacin residues were found 40% in livers, 36% in kidneys, 24% in thigh muscles, 20% in breast muscles, and 26% in eggs. Amoxicillin residues were found 48% in livers, 30% in kidneys, 26% in thigh muscles, 22% in breast muscles, and 24% in eggs. The most frequently detected antibiotic residues by both MIT and TLC were found in liver tissue, tetracycline (48%, ciprofloxacin (46%, enrofloxacin (40%, and amoxicillin (42% were found in liver. Breast muscle tissue was least likely to contain antibiotic residues (24%. Tetracycline (p=0.01 and amoxicillin (p=0.03 residues had

Residual stress by repair welds

International Nuclear Information System (INIS)

Mochizuki, Masahito; Toyoda, Masao

2003-01-01

Residual stress by repair welds is computed using the thermal elastic-plastic analysis with phase-transformation effect. Coupling phenomena of temperature, microstructure, and stress-strain fields are simulated in the finite-element analysis. Weld bond of a plate butt-welded joint is gouged and then deposited by weld metal in repair process. Heat source is synchronously moved with the deposition of the finite-element as the weld deposition. Microstructure is considered by using CCT diagram and the transformation behavior in the repair weld is also simulated. The effects of initial stress, heat input, and weld length on residual stress distribution are studied from the organic results of numerical analysis. Initial residual stress before repair weld has no influence on the residual stress after repair treatment near weld metal, because the initial stress near weld metal releases due to high temperature of repair weld and then stress by repair weld regenerates. Heat input has an effect for residual stress distribution, for not its magnitude but distribution zone. Weld length should be considered reducing the magnitude of residual stress in the edge of weld bead; short bead induces high tensile residual stress. (author)

The effect of sludge water treatment plant residuals on the properties of compressed brick

Science.gov (United States)

Shamsudin, Shamrul-Mar; Shahidan, S.; Azmi, M. A. M.; Ghaffar, S. A.; Ghani, M. B. Abdul; Saiful Bahari, N. A. A.; Zuki, S. S. M.

2017-11-01

The focus of this study is on the production of compressed bricks which contains sludge water treatment plant (SWTP) residuals obtained from SAJ. The main objective of this study is to utilise and incorporate discarded material (SWTP) in the form of residual solution to produce compressed bricks. This serves as one of the recycling efforts to conserve the environment. This study determined the optimum mix based on a mix ratio of 1:2:4 (cement: sand: soil) in the production of compressed bricks where 5 different mixes were investigated i. e. 0%, 5%, 10%, 20%, and 30% of water treatment plant residue solution. The production of the compressed bricks is in accordance with the Malaysian Standard MS 7.6: 1972 and British Standard BS 3921: 1985 - Compressive Strength & Water Absorption. After being moulded and air dried, the cured bricks were subjected to compression tests and water absorption tests. Based on the tests conducted, it was found that 20% of water treatment plant residue solution which is equivalent to 50% of soil content replacement with a mix composition of [10: cement] [20: sand] [20: soil] [20: water treatment plant residue solution] is the optimum mix. It was also observed that the bricks containing SWTP residuals were lighter in weight compared to the control specimens

Thermal conductivity of niobium single crystals in a magnetic field

International Nuclear Information System (INIS)

Gladun, C.; Vinzelberg, H.

1980-01-01

The thermal conductivity in longitudinal magnetic fields up to 5 T and in the temperature range 3.5 to 15 K is measured in two high purity niobium single crystals having residual resistivity ratios of 22700 and 19200 and orientations of the rod axis [110] and [100]. The investigations show that by means of the longitudinal magnetic field the thermal conductivity may decrease only to a limiting value. In the crystal directions [110] and [100] for the ratio of the thermal conductivity in zero field and the thermal conductivity in the saturation field the temperature-independent factors 1.92 and 1.27, respectively, are determined. With the aid of these factors the thermal conductivity in the normal state is evaluated from the measured values of thermal conductivity below Tsub(c) in the magnetic field. The different conduction and scattering mechanisms are discussed. (author)

Thermal conductivity measurements in unsaturated hydrate-bearing sediments

Science.gov (United States)

Dai, Sheng; Cha, Jong-Ho; Rosenbaum, Eilis J.; Zhang, Wu; Seol, Yongkoo

2015-08-01

Current database on the thermal properties of hydrate-bearing sediments remains limited and has not been able to capture their consequential changes during gas production where vigorous phase changes occur in this unsaturated system. This study uses the transient plane source (TPS) technique to measure the thermal conductivity of methane hydrate-bearing sediments with various hydrate/water/gas saturations. We propose a simplified method to obtain thermal properties from single-sided TPS signatures. Results reveal that both volume fraction and distribution of the pore constituents govern the thermal conductivity of unsaturated specimens. Thermal conductivity hysteresis is observed due to water redistribution and fabric change caused by hydrate formation and dissociation. Measured thermal conductivity increases evidently when hydrate saturation Sh > 30-40%, shifting upward from the geometric mean model prediction to a Pythagorean mixing model. These observations envisage a significant drop in sediment thermal conductivity when residual hydrate/water saturation falls below ~40%, hindering further gas production.

Lemna minor tolerance to metal-working fluid residues: implications for rhizoremediation.

Science.gov (United States)

Grijalbo, L; Becerril, J M; Barrutia, O; Gutierrez-Mañero, J; Lucas Garcia, J A

2016-07-01

For the first time in the literature, duckweed (Lemna minor) tolerance (alone or in combination with a consortium of bacteria) to spent metal-working fluid (MWF) was assessed, together with its capacity to reduce the chemical oxygen demand (COD) of this residue. In a preliminary study, L. minor response to pre-treated MWF residue (ptMWF) and vacuum-distilled MWF water (MWFw) was tested. Plants were able to grow in both residues at different COD levels tested (up to 2300 mg·l(-1) ), showing few toxicity symptoms (mainly growth inhibition). Plant response to MWFw was more regular and dose responsive than when exposed to ptMWF. Moreover, COD reduction was less significant in ptMWF. Thus, based on these preliminary results, a second study was conducted using MWFw to test the effectiveness of inoculation with a bacterial consortium isolated from a membrane bioreactor fed with the same residue. After 5 days of exposure, COD in solutions containing inoculated plants was significantly lower than in non-inoculated ones. Moreover, inoculation reduced β+γ-tocopherol levels in MWFw-exposed plants, suggesting pollutant imposed stress was reduced. We therefore conclude from that L. minor is highly tolerant to spent MWF residues and that this species can be very useful, together with the appropriate bacterial consortium, in reducing COD of this residue under local legislation limits and thus minimise its potential environmental impact. Interestingly, the lipophilic antioxidant tocopherol (especially the sum of β+γ isomers) proved to be an effective plant biomarker of pollution. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

Residue dissipation and processing factor for dimethomorph, famoxadone and cymoxanil during raisin preparation.

Science.gov (United States)

Shabeer T P, Ahammed; Banerjee, Kaushik; Jadhav, Manjusha; Girame, Rushali; Utture, Sagar; Hingmire, Sandip; Oulkar, Dasharath

2015-03-01

A method was validated for the simultaneous analysis of the residues of dimethomorph, famoxadone and cymoxanil in grape and raisin matrix by ethyl acetate based extraction and liquid chromatography tandem mass spectrometric analysis. Field studies were conducted to evaluate the dissipation rate kinetics and processing factor (PF) for these pesticides during raisin making. Residue data during the drying process were best fitted to 1st+1st order rate kinetics with half-life ranging between 8-9 days for dimethomorph, 12-13 days for famoxadone and 9-10 days for cymoxanil at single dose (SD) and double dose (DD), respectively. PF values calculated were 1.03 and 1.14 for dimethomorph, 1.95 and 2.09 for famoxadone, and 1.99 and 1.35 for cymoxanil at SD and DD, respectively. PF value >1 indicates concentration of the residues during raisin making. The residues of detected pesticides in market samples of raisins were devoid of any risk of acute toxicity related to dietary exposure. Copyright © 2014 Elsevier Ltd. All rights reserved.

An extension of command shaping methods for controlling residual vibration using frequency sampling

Science.gov (United States)

Singer, Neil C.; Seering, Warren P.

1992-01-01

The authors present an extension to the impulse shaping technique for commanding machines to move with reduced residual vibration. The extension, called frequency sampling, is a method for generating constraints that are used to obtain shaping sequences which minimize residual vibration in systems such as robots whose resonant frequencies change during motion. The authors present a review of impulse shaping methods, a development of the proposed extension, and a comparison of results of tests conducted on a simple model of the space shuttle robot arm. Frequency shaping provides a method for minimizing the impulse sequence duration required to give the desired insensitivity.

Dysregulation of TIM-3-galectin-9 pathway in the cystic fibrosis airways.

LENUS (Irish Health Repository)

Vega-Carrascal, Isabel

2012-02-01

The T-cell Ig and mucin domain-containing molecules (TIMs) have emerged as promising therapeutic targets to correct abnormal immune function in several autoimmune and chronic inflammatory conditions. It has been reported that proinflammatory cytokine dysregulation and neutrophil-dominated inflammation are the main causes of morbidity in cystic fibrosis (CF). However, the role of TIM receptors in CF has not been investigated. In this study, we demonstrated that TIM-3 is constitutively overexpressed in the human CF airway, suggesting a link between CF transmembrane conductance regulator (CFTR) function and TIM-3 expression. Blockade of CFTR function with the CFTR inhibitor-172 induced an upregulation of TIM-3 and its ligand galectin-9 in normal bronchial epithelial cells. We also established that TIM-3 serves as a functional receptor in bronchial epithelial cells, and physiologically relevant concentrations of galectin-9 induced TIM-3 phosphorylation, resulting in increased IL-8 production. In addition, we have demonstrated that both TIM-3 and galectin-9 undergo rapid proteolytic degradation in the CF lung, primarily because of neutrophil elastase and proteinase-3 activity. Our results suggest a novel intrinsic defect that may contribute to the neutrophil-dominated immune response in the CF airways.

Dysregulation of TIM-3-galectin-9 pathway in the cystic fibrosis airways.

LENUS (Irish Health Repository)

Vega-Carrascal, Isabel

2011-03-01

The T-cell Ig and mucin domain-containing molecules (TIMs) have emerged as promising therapeutic targets to correct abnormal immune function in several autoimmune and chronic inflammatory conditions. It has been reported that proinflammatory cytokine dysregulation and neutrophil-dominated inflammation are the main causes of morbidity in cystic fibrosis (CF). However, the role of TIM receptors in CF has not been investigated. In this study, we demonstrated that TIM-3 is constitutively overexpressed in the human CF airway, suggesting a link between CF transmembrane conductance regulator (CFTR) function and TIM-3 expression. Blockade of CFTR function with the CFTR inhibitor-172 induced an upregulation of TIM-3 and its ligand galectin-9 in normal bronchial epithelial cells. We also established that TIM-3 serves as a functional receptor in bronchial epithelial cells, and physiologically relevant concentrations of galectin-9 induced TIM-3 phosphorylation, resulting in increased IL-8 production. In addition, we have demonstrated that both TIM-3 and galectin-9 undergo rapid proteolytic degradation in the CF lung, primarily because of neutrophil elastase and proteinase-3 activity. Our results suggest a novel intrinsic defect that may contribute to the neutrophil-dominated immune response in the CF airways.

Identification of residue pairing in interacting β-strands from a predicted residue contact map.

Science.gov (United States)

Mao, Wenzhi; Wang, Tong; Zhang, Wenxuan; Gong, Haipeng

2018-04-19

Despite the rapid progress of protein residue contact prediction, predicted residue contact maps frequently contain many errors. However, information of residue pairing in β strands could be extracted from a noisy contact map, due to the presence of characteristic contact patterns in β-β interactions. This information may benefit the tertiary structure prediction of mainly β proteins. In this work, we propose a novel ridge-detection-based β-β contact predictor to identify residue pairing in β strands from any predicted residue contact map. Our algorithm RDb 2 C adopts ridge detection, a well-developed technique in computer image processing, to capture consecutive residue contacts, and then utilizes a novel multi-stage random forest framework to integrate the ridge information and additional features for prediction. Starting from the predicted contact map of CCMpred, RDb 2 C remarkably outperforms all state-of-the-art methods on two conventional test sets of β proteins (BetaSheet916 and BetaSheet1452), and achieves F1-scores of ~ 62% and ~ 76% at the residue level and strand level, respectively. Taking the prediction of the more advanced RaptorX-Contact as input, RDb 2 C achieves impressively higher performance, with F1-scores reaching ~ 76% and ~ 86% at the residue level and strand level, respectively. In a test of structural modeling using the top 1 L predicted contacts as constraints, for 61 mainly β proteins, the average TM-score achieves 0.442 when using the raw RaptorX-Contact prediction, but increases to 0.506 when using the improved prediction by RDb 2 C. Our method can significantly improve the prediction of β-β contacts from any predicted residue contact maps. Prediction results of our algorithm could be directly applied to effectively facilitate the practical structure prediction of mainly β proteins. All source data and codes are available at http://166.111.152.91/Downloads.html or the GitHub address of https://github.com/wzmao/RDb2C .

Residuals and the Residual-Based Statistic for Testing Goodness of Fit of Structural Equation Models

Science.gov (United States)

Foldnes, Njal; Foss, Tron; Olsson, Ulf Henning

2012-01-01

The residuals obtained from fitting a structural equation model are crucial ingredients in obtaining chi-square goodness-of-fit statistics for the model. The authors present a didactic discussion of the residuals, obtaining a geometrical interpretation by recognizing the residuals as the result of oblique projections. This sheds light on the…

Residual herbicide study on selected Hanford Site roadsides

Energy Technology Data Exchange (ETDEWEB)

Smith, J.L.; Kemp, C.J.; Sackschewsky, M.R.

1993-08-01

Westinghouse Hanford Company routinely treats roadsides with herbicides to control undesirable plant growth. An experiment was conducted to test perennial grass germination in soils adjacent to roadways of the Hanford Site. The primary variable was the distance from the roadside. A simple germination test was executed in a controlled-environment chamber to determine the residual effects of these applications. As expected, the greatest herbicide activity was found directly adjacent to the roadway, approximately 0 to 20 ft (0 to 6.3 m) from the roadway.

Removal of residual nuclei following a cavitation event using low-amplitude ultrasound.

Science.gov (United States)

Duryea, Alexander P; Cain, Charles A; Tamaddoni, Hedieh A; Roberts, William W; Hall, Timothy L

2014-10-01

Microscopic residual bubble nuclei can persist on the order of 1 s following a cavitation event. These bubbles can limit the efficacy of ultrasound therapies such as shock wave lithotripsy and histotripsy, because they attenuate pulses that arrive subsequent to their formation and seed repetitive cavitation activity at a discrete set of sites (cavitation memory). Here, we explore a strategy for the removal of these residual bubbles following a cavitation event, using low-amplitude ultrasound pulses to stimulate bubble coalescence. All experiments were conducted in degassed water and monitored using high-speed photography. In each case, a 2-MHz histotripsy transducer was used to initiate cavitation activity (a cavitational bubble cloud), the collapse of which generated a population of residual bubble nuclei. This residual nuclei population was then sonicated using a 1 ms pulse from a separate 500-kHz transducer, which we term the bubble removal pulse. Bubble removal pulse amplitudes ranging from 0 to 1.7 MPa were tested, and the backlit area of shadow from bubbles remaining in the field following bubble removal was calculated to quantify efficacy. It was found that an ideal amplitude range exists (roughly 180 to 570 kPa) in which bubble removal pulses stimulate the aggregation and subsequent coalescence of residual bubble nuclei, effectively removing them from the field. Further optimization of bubble removal pulse sequences stands to provide an adjunct to cavitation-based ultrasound therapies such as shock wave lithotripsy and histotripsy, mitigating the effects of residual bubble nuclei that currently limit their efficacy.

Study on the pelletizing of sulfate residue with magnetite concentrate in grate-kiln system

Directory of Open Access Journals (Sweden)

Shufeng Y.

2010-01-01

Full Text Available The experiment on the feasibility of pelletizing with magnetite concentrate and the wasted sulfate residue was carried out, to research the performance of pellet in grate-kiln system and simulate the grate-kiln pelletizing process in the micro-pellet roasting simulation system in laboratory, and the process experiments on preheating and roasting sections were conducted. The results show that in order to obtain pellet with good performance and the magnetite concentrate should be over 20 in mass percent, the suitable pelletizing time is about 10 min and moisture is around 12.5%. Also, according to the process parameters of drying and preheating sections obtained from experiment, it will be successful to use magnetite concentrate and the wasted sulfate residue for pelletizing, which exploits a new way for the use of sulfate residue.

Influence of different disease control pesticide strategies on multiple pesticide residue levels in apple

DEFF Research Database (Denmark)

Poulsen, Mette Erecius; Naef, A.; Gasser, S.

2009-01-01

Seven pesticide application strategies were investigated to control apple scab (Venturia inaequalis) and powdery mildew (Podosphaera leucotricha) and, at the same time.. fulfil the new quality standards implemented by some German retailers. These demand that pesticide residues should be below 80....... The trials were conducted at two sites in Switzerland, in 2007, and all strategies and applications were in accordance with actual practice. Four replicates of apple samples from each strategy were then analysed for pesticide residues. The incidence of infection with apple scab and powdery mildew were...... monitored during the season in order to evaluate the efficacy of the different strategies. The efficacies of the different strategies against apple scab and powdery mildew were between 84% and 100% successful. In general, the level of pesticide residues found correlated with application rate and time...

Assessment of the radiological conditions in areas of Kuwait with residues of depleted uranium

International Nuclear Information System (INIS)

Cabianca, T.; Danesi, P.R.; Linsley, G.

2004-01-01

The 1991 Gulf War was the first conflict in which DU munitions were used extensively. After this conflict, questions arose regarding the possible link between exposure to ionizing radiation from DU and harmful biological effects. In view of these concerns, the Government of Kuwait, in February 2001, requested the IAEA to conduct an assessment to evaluate the possible radiological impact of residues of DU munitions from the 1991 Gulf War at 11 locations in Kuwait. For this purpose, the IAEA assembled a team of senior experts, who visited Kuwait in September 2001 to carry out a preliminary assessment of the sites and to evaluate the available information. In February 2002 scientists from the IAEA, the Spiez Laboratory (Switzerland), representing UNEP, and the Radiation Protection Department of the Ministry of Health of Kuwait, carried out a sampling campaign at these sites. Around 200 environmental samples, including soil, water and vegetation, were collected during the campaign and subsequently analysed. This study constitutes the first comprehensive radiological assessment of compliance with international radiation protection criteria and standards for areas with residues of DU munitions conducted under the auspices of the IAEA. The findings of this investigation indicate that DU does not pose a radiological hazard to the population of Kuwait. Annual radiation doses arising from exposure to DU residues would be of a few micro-sieverts, well below the annual doses from natural sources of radiation and far below the reference level recommended by the IAEA as a criterion to help establish whether remedial actions are necessary. DU penetrators can still be found at some of the locations visited. Prolonged skin contact with these residues is the only possible pathway that could result in exposures of radiological significance. As long as access to these areas remains restricted, the likelihood that members of the public could come into contact with these residues is low

Cortisol regulation of ion transporter mRNA in Atlantic salmon gill and the effect of salinity on the signaling pathway

DEFF Research Database (Denmark)

Kiilerich, Pia; Kristiansen, Karsten; Madsen, Steffen S

2007-01-01

Based on real-time RT-PCR, analysis of transcripts of selected ion-regulatory proteins (Na(+), K(+)-ATPase alpha1a and alpha1b subunit, Na(+), K(+), 2Cl(-) cotransporter, cystic fibrosis transmembrane conductance regulator (CFTR), and H(+)-ATPase B-subunit), the regulatory role of cortisol and th...

Machine for compacting solid residues

International Nuclear Information System (INIS)

Herzog, J.

1981-11-01

Machine for compacting solid residues, particularly bulky radioactive residues, constituted of a horizontally actuated punch and a fixed compression anvil, in which the residues are first compacted horizontally and then vertically. Its salient characteristic is that the punch and the compression anvil have embossments on the compression side and interpenetrating plates in the compression position [fr

Biodiesel of distilled hydrogenated fat and biodiesel of distilled residual oil: fuel consumption in agricultural tractor

Energy Technology Data Exchange (ETDEWEB)

Camara, Felipe Thomaz da; Lopes, Afonso; Silva, Rouverson Pereira da; Oliveira, Melina Cais Jejcic; Furlani, Carlos Eduardo Angeli [Universidade Estadual Paulista (UNESP), Jaboticabal, SP (Brazil); Dabdoub, Miguel Joaquim [Universidade de Sao Paulo (USP), Ribeirao Preto (Brazil)

2008-07-01

Great part of the world-wide oil production is used in fry process; however, after using, such product becomes an undesirable residue, and the usual methods of discarding of these residues, generally contaminate the environment, mainly the rivers. In function of this, using oil and residual fat for manufacturing biodiesel, besides preventing ambient contamination, turning up an undesirable residue in to fuel. The present work had as objective to evaluate the fuel consumption of a Valtra BM100 4x2 TDA tractor functioning with methylic biodiesel from distilled hydrogenated fat and methylic biodiesel from distilled residual oil, in seven blends into diesel. The work was conducted at the Department of Agricultural Engineering, at UNESP - Jaboticabal, in an entirely randomized block statistical design, factorial array of 2 x 7, with three repetitions. The factors combinations were two types of methylic distilled biodiesel (residual oil and hydrogenated fat) and seven blends (B{sub 0}, B{sub 5}, B{sub 1}5, B{sub 2}5, B{sub 5}0, B{sub 7}5 and B{sub 1}00). The results had evidenced that additioning 15% of biodiesel into diesel, the specific consumption was similar, and biodiesel of residual oil provided less consumption than biodiesel from hydrogenated fat. (author)

Residual stress concerns in containment analysis

International Nuclear Information System (INIS)

Costantini, F.; Kulak, R. F.; Pfeiffer, P. A.

1997-01-01

The manufacturing of steel containment vessels starts with the forming of flat plates into curved plates. A steel containment structure is made by welding individual plates together to form the sections that make up the complex shaped vessels. The metal forming and welding process leaves residual stresses in the vessel walls. Generally, the effect of metal forming residual stresses can be reduced or virtually eliminated by thermally stress relieving the vesseL In large containment vessels this may not be practical and thus the residual stresses due to manufacturing may become important. The residual stresses could possibly tiect the response of the vessel to internal pressurization. When the level of residual stresses is significant it will affect the vessel's response, for instance the yielding pressure and possibly the failure pressure. The paper will address the effect of metal forming residual stresses on the response of a generic pressure vessel to internal pressurization. A scoping analysis investigated the effect of residual forming stresses on the response of an internally pressurized vessel. A simple model was developed to gain understanding of the mechanics of the problem. Residual stresses due to the welding process were not considered in this investigation

Solid Phase Microextraction (SPME in Determination of Pesticide Residues in Soil Samples

Directory of Open Access Journals (Sweden)

Rada Đurović

2011-01-01

Full Text Available The basic principles and application possibilities of the methods based on solid phase microextraction (SPME in the analysis of pesticide residues in soil samples are presented in the paper. The most important experimental parameters which affect SPME efficacy inpesticide determination (type and thickness of microextraction fiber, duration of microextraction,temperature at which it is conducted, effect of addition of salts (the effect of efflorescence,temperature and time of desorption, the choice of optimal solvent for pesticide exctraction from the soil and the optimal number of extraction steps, as well as general guidelines for their optimization are also shown. In the end, current applications of SPMEmethods in the analysis of pesticide residues in soil samples are presented.

Characterization of Hospital Residuals

International Nuclear Information System (INIS)

Blanco Meza, A.; Bonilla Jimenez, S.

1997-01-01

The main objective of this investigation is the characterization of the solid residuals. A description of the handling of the liquid and gassy waste generated in hospitals is also given, identifying the source where they originate. To achieve the proposed objective the work was divided in three stages: The first one was the planning and the coordination with each hospital center, in this way, to determine the schedule of gathering of the waste can be possible. In the second stage a fieldwork was made; it consisted in gathering the quantitative and qualitative information of the general state of the handling of residuals. In the third and last stage, the information previously obtained was organized to express the results as the production rate per day by bed, generation of solid residuals for sampled services, type of solid residuals and density of the same ones. With the obtained results, approaches are settled down to either determine design parameters for final disposition whether for incineration, trituration, sanitary filler or recycling of some materials, and storage politics of the solid residuals that allow to determine the gathering frequency. The study concludes that it is necessary to improve the conditions of the residuals handling in some aspects, to provide the cleaning personnel of the equipment for gathering disposition and of security, minimum to carry out this work efficiently, and to maintain a control of all the dangerous waste, like sharp or polluted materials. In this way, an appreciable reduction is guaranteed in the impact on the atmosphere. (Author) [es

Endoscopic Endonasal Versus Microscopic Transsphenoidal Surgery for Recurrent and/or Residual Pituitary Adenomas.

Science.gov (United States)

Esquenazi, Yoshua; Essayed, Walid I; Singh, Harminder; Mauer, Elizabeth; Ahmed, Mudassir; Christos, Paul J; Schwartz, Theodore H

2017-05-01

Surgery for recurrent/residual pituitary adenomas is increasingly being performed through endoscopic surgery. Whether this new technology has altered the indications and outcomes of surgery is unknown. We conducted a systematic review and meta-analysis of published studies to compare the indications and outcomes between microscopic and endoscopic approaches. A PubMed search was conducted (1985-2015) to identify surgical series of endoscopic endonasal and microscopic transsphenoidal resection of residual or recurrent pituitary adenomas. Data were extracted regarding tumor characteristics, surgical treatment, extent of resection, endocrine remission, visual outcome, and complications. Twenty-one studies met inclusion criteria. A total of 292 patients were in the endoscopic group, and 648 patients were in the microscopic group. Endoscopic cases were more likely nonfunctional (P < 0.001) macroadenomas (P < 0.001) with higher rates of cavernous sinus invasion (P = 0.012). The pooled rate of gross total tumor resection was 53.5% for the endoscopic group and 46.6% for the microscopic group. Endocrine remission was achieved in 53.0% and 46.7% of patients, and visual improvement occurred in 73.2% and 49.6% for the endoscopic and microscopic groups. Cerebrospinal fluid leak and pituitary insufficiency were higher in the endoscopic group. This meta-analysis indicates that the use of the endoscope to reoperate on residual or recurrent adenomas has only led to modest increases in resection rates. However, larger more complex cases are being tackled, so direct comparisons are misleading. The most dramatic change has been in visual improvement along with modest increases in risk. Reoperation for recurrent or residual adenomas is a safe and effective treatment option. Copyright © 2017 Elsevier Inc. All rights reserved.

Laboratory evaluation of particle size, food contamination, and residual efficacy of pyrethrin + methoprene aerosol

Science.gov (United States)

A series of tests were conducted to determine residual efficacy of pyrethrin+methoprene aerosol to manage larvae of selected stored product insects. Efficacy was assessed through emergence of morphologically-normal adults and through a quantitative developmental index with values ranging from 1, for...

Applications of bauxite residue: A mini-review.

Science.gov (United States)

Verma, Ajay S; Suri, Narendra M; Kant, Suman

2017-10-01

Bauxite residue is the waste generated during alumina production by Bayer's process. The amount of bauxite residue (40-50 wt%) generated depends on the quality of bauxite ore used for the processing. High alkalinity and high caustic content in bauxite residue causes environmental risk for fertile soil and ground water contamination. The caustic (NaOH) content in bauxite residue leads to human health risks, like dermal problems and irritation to eyes. Moreover, disposal of bauxite residue requires a large area; such problems can only be minimised by utilising bauxite residue effectively. For two decades, bauxite residue has been used as a binder in cement industries and filler/reinforcement for composite materials in the automobile industry. Valuable metals and oxides, like alumina (Al 2 O 3 ), titanium oxide (TiO 2 ) and iron oxide Fe 2 O 3 , were extracted from bauxite residue to reduce waste. Bauxite residue was utilised in construction and structure industries to make geopolymers. It was also used in the making of glass-ceramics and a coating material. Recently bauxite residue has been utilised to extract rare earth elements like scandium (Sc), yttrium (Y), lanthanum (La), cerium (Ce), neodymium (Nd) and dysprosium (Dy). In this review article, the mineralogical characteristics of bauxite residue are summarised and current progresses on utilisation of bauxite residue in different fields of science and engineering are presented in detail.

Welding induced residual stress evaluation using laser-generated Rayleigh waves

Science.gov (United States)

Ye, Chong; Zhou, Yuanlai; Reddy, Vishnu V. B.; Mebane, Aaron; Ume, I. Charles

2018-04-01

Welding induced residual stress could affect the dimensional stability, fatigue life, and chemical resistance of the weld joints. Ultrasonic method serves as an important non-destructive tool for the residual stress evaluation due to its easy implementation, low cost and wide application to different materials. Residual stress would result in the ultrasonic wave velocity variation, which is the so called acoustoelastic effect. In this paper, Laser/EMAT ultrasonic technique was proposed to experimentally study the relative velocity variation ΔV/V of Rayleigh wave, which has the potential to evaluate surface/subsurface longitudinal residual stress developed during the Gas Metal Arc Welding process. Broad band ultrasonic waves were excited by pulsed Q-Switched Nd: YAG laser. An electromagnetic acoustic transducer (EMAT) attached to the welded plates was used to capture the Rayleigh wave signals propagating along the weld seam direction. Different time of flight measurements were conducted by varying the distance between the weld seam and Rayleigh wave propagating path in the range of 0 to 45 mm. The maximum relative velocity difference was found on the weld seam. With the increasing distance away from the weld seam, the relative velocity difference sharply decreased to negative value. With further increase in distance, the relative velocity difference slowly increased and approached zero. The distribution of relative velocity variations indicates that tensile stress appears in the melted zone as it becomes compressive near the heat-affected zone.

Gene delivery to the lungs: pulmonary gene therapy for cystic fibrosis.

Science.gov (United States)

Villate-Beitia, Ilia; Zarate, Jon; Puras, Gustavo; Pedraz, José Luis

2017-07-01

Cystic fibrosis (CF) is a monogenic autosomal recessive disorder where the defective gene, the cystic fibrosis transmembrane conductance regulator (CFTR), is well identified. Moreover, the respiratory tract can be targeted through noninvasive aerosolized formulations for inhalation. Therefore, gene therapy is considered a plausible strategy to address this disease. Conventional gene therapy strategies rely on the addition of a correct copy of the CFTR gene into affected cells in order to restore the channel activity. In recent years, genome correction strategies have emerged, such as zinc-finger nucleases, transcription activator-like effector nucleases and clustered regularly interspaced short palindromic repeats associated to Cas9 nucleases. These gene editing tools aim to repair the mutated gene at its original genomic locus with high specificity. Besides, the success of gene therapy critically depends on the nucleic acids carriers. To date, several clinical studies have been carried out to add corrected copies of the CFTR gene into target cells using viral and non-viral vectors, some of them with encouraging results. Regarding genome editing systems, preliminary in vitro studies have been performed in order to repair the CFTR gene. In this review, after briefly introducing the basis of CF, we discuss the up-to-date gene therapy strategies to address the disease. The review focuses on the main factors to take into consideration when developing gene delivery strategies, such as the design of vectors and plasmid DNA, in vitro/in vivo tests, translation to human use, administration methods, manufacturing conditions and regulatory issues.

Management of NORM Residues

International Nuclear Information System (INIS)

2013-06-01

The IAEA attaches great importance to the dissemination of information that can assist Member States in the development, implementation, maintenance and continuous improvement of systems, programmes and activities that support the nuclear fuel cycle and nuclear applications, and that address the legacy of past practices and accidents. However, radioactive residues are found not only in nuclear fuel cycle activities, but also in a range of other industrial activities, including: - Mining and milling of metalliferous and non-metallic ores; - Production of non-nuclear fuels, including coal, oil and gas; - Extraction and purification of water (e.g. in the generation of geothermal energy, as drinking and industrial process water; in paper and pulp manufacturing processes); - Production of industrial minerals, including phosphate, clay and building materials; - Use of radionuclides, such as thorium, for properties other than their radioactivity. Naturally occurring radioactive material (NORM) may lead to exposures at some stage of these processes and in the use or reuse of products, residues or wastes. Several IAEA publications address NORM issues with a special focus on some of the more relevant industrial operations. This publication attempts to provide guidance on managing residues arising from different NORM type industries, and on pertinent residue management strategies and technologies, to help Member States gain perspectives on the management of NORM residues

Immobilization of acid digestion residue

International Nuclear Information System (INIS)

Greenhalgh, W.O.; Allen, C.R.

1983-01-01

Acid digestion treatment of nuclear waste is similar to incineration processes and results in the bulk of the waste being reduced in volume and weight to some residual solids termed residue. The residue is composed of various dispersible solid materials and typically contains the resultant radioactivity from the waste. This report describes the immobilization of the residue in portland cement, borosilicate glass, and some other waste forms. Diagrams showing the cement and glass virtification parameters are included in the report as well as process steps and candidate waste product forms. Cement immobilization is simplest and probably least expensive; glass vitrification exhibits the best overall volume reduction ratio

Landfill Mining of Shredder Residues

DEFF Research Database (Denmark)

Hansen, Jette Bjerre; Hyks, Jiri; Shabeer Ahmed, Nassera

In Denmark, shredder residues (SR) are classified as hazardous waste and until January 2012 the all SR were landfilled. It is estimated that more than 1.8 million tons of SR have been landfilled in mono cells. This paper describes investigations conducted at two Danish landfills. SR were excavated...... from the landfills and size fractionated in order to recover potential resources such as metal and energy and to reduce the amounts of SR left for re-landfilling. Based on the results it is estimated that 60-70% of the SR excavated could be recovered in terms of materials or energy. Only a fraction...... with particle size less than 5 mm needs to be re-landfilled at least until suitable techniques are available for recovery of materials with small particle sizes....

Residual stress in ceramics and ceramic composites

International Nuclear Information System (INIS)

Oden, M.

1992-01-01

Residual stresses in Si 3 N 4 and SiC have been measured with X-ray diffraction after grinding and thermal shock. The produced surface stresses are compressive after both treatments. The stresses show a strong dependence on the quenching temperature up to a certain temperature when cracks relax the stresses. The influence of the amount of reinforcing phase on the residual stress state in a Al 2 O 3 /SiC whisker composite was investigated and correlated to a modified Eshelby model. The agreement is excellent. The composite was quenched in liquid He (4K) and the stress state measured after show no relaxation of stresses, indicating elastic behaviour. An in situ strain measurement as a function of temperature conducted on a Al 2 O 3 /SiC whisker composite and a SiC/TiB 2 particle composite show very good agreement with the Eshelby model for the Al 2 O 3 /SiC system but not agreement for the SiC/TiB 2 system. The reason is believed to be stress relaxation during sample preparation. (au) (53 refs., 24 figs., 14 tabs.)

Residual stress characterization of steel TIG welds by neutron diffraction and by residual magnetic stray field mappings

Science.gov (United States)

Stegemann, Robert; Cabeza, Sandra; Lyamkin, Viktor; Bruno, Giovanni; Pittner, Andreas; Wimpory, Robert; Boin, Mirko; Kreutzbruck, Marc

2017-03-01

The residual stress distribution of tungsten inert gas welded S235JRC+C plates was determined by means of neutron diffraction (ND). Large longitudinal residual stresses with maxima around 600 MPa were found. With these results as reference, the evaluation of residual stress with high spatial resolution GMR (giant magneto resistance) sensors was discussed. The experiments performed indicate a correlation between changes in residual stresses (ND) and the normal component of local residual magnetic stray fields (GMR). Spatial variations in the magnetic field strength perpendicular to the welds are in the order of the magnetic field of the earth.

Bioavailability of residual polycyclic aromatic hydrocarbons following enhanced natural attenuation of creosote-contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Juhasz, Albert L., E-mail: albert.juhasz@unisa.edu.a [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Smith, Euan [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Waller, Natasha [CSIRO Land and Water, Glen Osmond, SA 5064 (Australia); Stewart, Richard [Remediate, Kent Town, SA 5067 (Australia); Weber, John [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia)

2010-02-15

The impact of residual PAHs (2250 +- 71 mug total PAHs g{sup -1}) following enhanced natural attenuation (ENA) of creosote-contaminated soil (7767 +- 1286 mug total PAHs g{sup -1}) was assessed using a variety of ecological assays. Microtox{sup TM} results for aqueous soil extracts indicated that there was no significant difference in EC{sub 50} values for uncontaminated, pre- and post-remediated soil. However, in studies conducted with Eisenia fetida, PAH bioaccumulation was reduced by up to 6.5-fold as a result of ENA. Similarly, Beta vulgaris L. biomass yields were increased 2.1-fold following ENA of creosote-contaminated soil. While earthworm and plant assays indicated that PAH bioavailability was reduced following ENA, the residual PAH fraction still exerted toxicological impacts on both receptors. Results from this study highlight that residual PAHs following ENA (presumably non-bioavailable to bioremediation) may still be bioavailable to important receptor organisms such as earthworms and plants. - Residual PAHs in creosote-contaminated soil following enhanced natural attenuation impacted negatively on ecological receptors.

Bioavailability of residual polycyclic aromatic hydrocarbons following enhanced natural attenuation of creosote-contaminated soil

International Nuclear Information System (INIS)

Juhasz, Albert L.; Smith, Euan; Waller, Natasha; Stewart, Richard; Weber, John

2010-01-01

The impact of residual PAHs (2250 ± 71 μg total PAHs g -1 ) following enhanced natural attenuation (ENA) of creosote-contaminated soil (7767 ± 1286 μg total PAHs g -1 ) was assessed using a variety of ecological assays. Microtox TM results for aqueous soil extracts indicated that there was no significant difference in EC 50 values for uncontaminated, pre- and post-remediated soil. However, in studies conducted with Eisenia fetida, PAH bioaccumulation was reduced by up to 6.5-fold as a result of ENA. Similarly, Beta vulgaris L. biomass yields were increased 2.1-fold following ENA of creosote-contaminated soil. While earthworm and plant assays indicated that PAH bioavailability was reduced following ENA, the residual PAH fraction still exerted toxicological impacts on both receptors. Results from this study highlight that residual PAHs following ENA (presumably non-bioavailable to bioremediation) may still be bioavailable to important receptor organisms such as earthworms and plants. - Residual PAHs in creosote-contaminated soil following enhanced natural attenuation impacted negatively on ecological receptors.

Radioactive material in residues of health services residues

International Nuclear Information System (INIS)

Costa R, A. Jr.; Recio, J.C.

2006-01-01

The work presents the operational actions developed by the one organ responsible regulator for the control of the material use radioactive in Brazil. Starting from the appearance of coming radioactive material of hospitals and clinical with services of nuclear medicine, material that that is picked up and transported in specific trucks for the gathering of residuals of hospital origin, and guided one it manufactures of treatment of residuals of services of health, where they suffer radiological monitoring before to guide them for final deposition in sanitary embankment, in the city of Sao Paulo, Brazil. The appearance of this radioactive material exposes a possible one violation of the norms that govern the procedures and practices in that sector in the country. (Author)

An accurate method for determining residual stresses with magnetic non-destructive techniques in welded ferromagnetic steels

International Nuclear Information System (INIS)

Vourna, P

2016-01-01

The scope of the present research work was to investigate the proper selection criteria for developing a suitable methodology for the accurate determination of residual stresses existing in welded parts. Magnetic non-destructive testing took place by the use of two magnetic non-destructive techniques: by the measurement of the magnetic Barkhausen noise and by the evaluation of the magnetic hysteresis loop parameters. The spatial distribution of residual stresses in welded metal parts by both non-destructive magnetic methods and two diffraction methods was determined. The conduction of magnetic measurements required an initial calibration of ferromagnetic steels. Based on the examined volume of the sample, all methods used were divided into two large categories: the first one was related to the determination of surface residual stress, whereas the second one was related to bulk residual stress determination. The first category included the magnetic Barkhausen noise and the X-ray diffraction measurements, while the second one included the magnetic permeability and the neutron diffraction data. The residual stresses determined by the magnetic techniques were in a good agreement with the diffraction ones. (paper)

Detection of chloramphenicol residue in bovine meat using Liquid Chromatography Mass Spectrometry

Directory of Open Access Journals (Sweden)

Widiastuti R

2014-03-01

Full Text Available Chloramphenicol (CAP is a broad spectrum antibiotic that has been banned in many countries due to its serius side effect to human. Detection of CAP residue in food has been determined to a minimum required performance limit (MRPL of 0.3 ng/g. The purpose of this research was to conduct the analysis of CAP residue in bovine meat by using LCMS and to study the presence of CAP residue in marketed bovine meat samples. LC separation was done on a Shimpack column C18 with ammonium acetate 10 mM/water as mobile phase, and ESI-MS analysis in negative ion mode. The coefficient of determination, R2 = 0.9981 at concentration of 0.125, 0.25, 0.63, 1,00 and 2.00 ng/g. Recovery at three fortification levels (0.25, 0.50 and 1.00 ng/g was in the range 77.5, 97.3 and 83.4%. The decision limit and the detection capability were 0.15 ng/g and 0.17 ng/g respectively. Analysis results of 52 marketed samples showed that CAP residue were detected in 9 samples in the concentration range of 0.14 to 2.70 ng/g and 6 among those positive samples were above the MRPL value. Therefore, it is important to increase the awareness and also to monitor regularly CAP residues in food originated from animal to provide safe food for the consumers.

Tank 16 Annulus Cleanout Analysis Doses at Seepline from Transport of Residual Tc-99 Wastes

International Nuclear Information System (INIS)

Collard, L.B.

1999-01-01

An analysis of residual Tc-99 in the Tank 16 annulus was conducted to assess the potential benefit from cleaning the annulus. One analysis was performed for the as-is case to determine seepline doses if no clean out occurs. Another analysis was performed assuming that ninety percent of existing contaminants are removed. Characterization data for samples retrieved from the annulus were used in the analysis. Only Tc-99 was analyzed because preliminary modeling identified it as the highest dose contributor. The effect of residual waste in piping was not analyzed

Improved crop residue cover estimates by coupling spectral indices for residue and moisture

Science.gov (United States)

Remote sensing assessment of soil residue cover (fR) and tillage intensity will improve our predictions of the impact of agricultural practices and promote sustainable management. Spectral indices for estimating fR are sensitive to soil and residue water content, therefore, the uncertainty of estima...

All azoospermic males should be screened for cystic fibrosis mutations before intracytoplasmic sperm injection.

LENUS (Irish Health Repository)

Mocanu, Edgar

2012-02-01

We assessed the frequency of CFTR mutations in groups with varying degrees of sub-fertility and compared these groups to a fertile male group with proven paternity. Screening for CFTR mutations should be routine for all azoospermic males, irrespective of obstructive or non-obstructive etiology, prior to proposing ICSI treatment. CFTR testing has no value in the investigation of non-azoospermic infertile males.

All azoospermic males should be screened for cystic fibrosis mutations before intracytoplasmic sperm injection.

LENUS (Irish Health Repository)

Mocanu, Edgar

2010-11-01

We assessed the frequency of CFTR mutations in groups with varying degrees of sub-fertility and compared these groups to a fertile male group with proven paternity. Screening for CFTR mutations should be routine for all azoospermic males, irrespective of obstructive or non-obstructive etiology, prior to proposing ICSI treatment. CFTR testing has no value in the investigation of non-azoospermic infertile males.

Statistical inference on residual life

CERN Document Server

Jeong, Jong-Hyeon

2014-01-01

This is a monograph on the concept of residual life, which is an alternative summary measure of time-to-event data, or survival data. The mean residual life has been used for many years under the name of life expectancy, so it is a natural concept for summarizing survival or reliability data. It is also more interpretable than the popular hazard function, especially for communications between patients and physicians regarding the efficacy of a new drug in the medical field. This book reviews existing statistical methods to infer the residual life distribution. The review and comparison includes existing inference methods for mean and median, or quantile, residual life analysis through medical data examples. The concept of the residual life is also extended to competing risks analysis. The targeted audience includes biostatisticians, graduate students, and PhD (bio)statisticians. Knowledge in survival analysis at an introductory graduate level is advisable prior to reading this book.

The recovery of sulphur, uranium, and gold from residues

International Nuclear Information System (INIS)

Ruhmer, W.T.; Botha, F.; Adams, J.S.

1977-01-01

The report describes the Amuran project in the Welkom area, which is being conducted by six members of the Anglo American Group. The project comprises three plants for the flotation of pyrite, a twin-stream uranium plant for the recovery of gold from calcines. Details of these plants including capital costs and estimated production are given. Mention is made of the adsorption of gold onto activated charcoal and wet high-intensity magnetic separation as possible suitable processes for these residues [af

Residual Stresses In 3013 Containers

International Nuclear Information System (INIS)

Mickalonis, J.; Dunn, K.

2009-01-01

The DOE Complex is packaging plutonium-bearing materials for storage and eventual disposition or disposal. The materials are handled according to the DOE-STD-3013 which outlines general requirements for stabilization, packaging and long-term storage. The storage vessels for the plutonium-bearing materials are termed 3013 containers. Stress corrosion cracking has been identified as a potential container degradation mode and this work determined that the residual stresses in the containers are sufficient to support such cracking. Sections of the 3013 outer, inner, and convenience containers, in both the as-fabricated condition and the closure welded condition, were evaluated per ASTM standard G-36. The standard requires exposure to a boiling magnesium chloride solution, which is an aggressive testing solution. Tests in a less aggressive 40% calcium chloride solution were also conducted. These tests were used to reveal the relative stress corrosion cracking susceptibility of the as fabricated 3013 containers. Significant cracking was observed in all containers in areas near welds and transitions in the container diameter. Stress corrosion cracks developed in both the lid and the body of gas tungsten arc welded and laser closure welded containers. The development of stress corrosion cracks in the as-fabricated and in the closure welded container samples demonstrates that the residual stresses in the 3013 containers are sufficient to support stress corrosion cracking if the environmental conditions inside the containers do not preclude the cracking process.

Bioethanol production from forestry residues: A comparative techno-economic analysis

International Nuclear Information System (INIS)

Frankó, Balázs; Galbe, Mats; Wallberg, Ola

2016-01-01

Highlights: • A proposed cellulosic ethanol biorefinery in Sweden was simulated with Aspen Plus. • Forestry residues with different bark contents were evaluated as raw materials. • The bark content negatively influenced the minimum ethanol selling price. • Sensitivity analyses were performed to assess the influence of raw material cost. - Abstract: A techno-economic analysis was conducted to assess the feasibility of using forestry residues with different bark contents for bioethanol production. A proposed cellulosic ethanol biorefinery in Sweden was simulated with Aspen Plus. The plant was assumed to convert different forestry assortments (sawdust and shavings, fuel logs, early thinnings, tops and branches, hog fuel and pulpwood) to ethanol, pellets, biogas and electricity. The intention was not to obtain absolute ethanol production costs for future facilities, but to assess and compare the future potential of utilizing different forestry residues for bioethanol production. The same plant design and operating conditions were assumed in all cases, and the effect of including bark on the whole conversion process, especially how it influenced the ethanol production cost, was studied. While the energy efficiency (not including district heating) obtained for the whole process was between 67 and 69% regardless of the raw material used, the ethanol production cost differed considerably; the minimum ethanol selling price ranging from 0.77 to 1.52 USD/L. Under the basic assumptions, all the forestry residues apart from sawdust and shavings exhibited a negative net present value at current market prices. The profitability decreased with increasing bark content of the raw material. Sensitivity analyses showed that, at current market prices, the utilization of bark-containing forestry residues will not provide significant cost improvement compared with pulpwood unless the conversion of cellulose and hemicellulose to monomeric sugars is improved.

Development of Radiometric and Allied Analytical Methods and Strategies to Strengthen National Residue Control Programmes for Antibiotic and Anthelmintic Veterinary Drug Residues. Final Report of a Coordinated Research Project

International Nuclear Information System (INIS)

2016-08-01

Awareness of food safety is rising among consumers, and many importing countries implement food control regulations to guarantee the quality and safety of imported foods for their consumers. Many developing countries have also taken steps to put in place control systems that encourage responsible use of veterinary medicines to combat possible drug resistance, control drug residues and ensure compliance with international and national standards. However, these countries still require the necessary know-how and skills to protect local consumers and to access international markets. One significant constraint is the capacity of laboratory services to generate surveillance data using reliable and cost effective analytical methods validated to national and international standards. The IAEA coordinated research project (CRP) on the Development of Radiometric and Allied Analytical Methods to Strengthen National Residue Control Programmes for Antibiotic and Anthelmintic Veterinary Drug Residues was initiated in 2009 to conduct work on robust nuclear and related technologies suitable for the screening and confirmatory analysis of residues of veterinary medicines, including antimicrobials and anthelmintics commonly used in animal production, with public health and trade significance. The CRP also explored mechanisms to enhance networking among research institutions involved in research on pharmacologically active veterinary drug residues in food (primarily) and environmental samples. The project was implemented by the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture between 2009 and 2014 and involved eleven research contracts and one technical contract, five research agreements and one institution. The CRP was a continuation of the CRP on the Development of Strategies for the Effective Monitoring of Veterinary Drug Residues in Livestock and Livestock Products in Developing Countries and the key findings are also summarized in this publication.

The effects of rape residue mulching on net global warming potential and greenhouse gas intensity from no-tillage paddy fields.

Science.gov (United States)

Zhang, Zhi-Sheng; Cao, Cou-Gui; Guo, Li-Jin; Li, Cheng-Fang

2014-01-01

A field experiment was conducted to provide a complete greenhouse gas (GHG) accounting for global warming potential (GWP), net GWP, and greenhouse gas intensity (GHGI) from no-tillage (NT) paddy fields with different amounts of oilseed rape residue mulch (0, 3000, 4000, and 6000 kg dry matter (DM) ha(-1)) during a rice-growing season after 3 years of oilseed rape-rice cultivation. Residue mulching treatments showed significantly more organic carbon (C) density for the 0-20 cm soil layer at harvesting than no residue treatment. During a rice-growing season, residue mulching treatments sequestered significantly more organic C from 687 kg C ha(-1) season(-1) to 1654 kg C ha(-1) season(-1) than no residue treatment. Residue mulching significantly increased emissions of CO2 and N2O but decreased CH4 emissions. Residue mulching treatments significantly increased GWP by 9-30% but significantly decreased net GWP by 33-71% and GHGI by 35-72% relative to no residue treatment. These results suggest that agricultural economic viability and GHG mitigation can be achieved simultaneously by residue mulching on NT paddy fields in central China.

Residual Structures in Latent Growth Curve Modeling

Science.gov (United States)

Grimm, Kevin J.; Widaman, Keith F.

2010-01-01

Several alternatives are available for specifying the residual structure in latent growth curve modeling. Two specifications involve uncorrelated residuals and represent the most commonly used residual structures. The first, building on repeated measures analysis of variance and common specifications in multilevel models, forces residual variances…

Optimization of Residual Stress of High Temperature Treatment Using Genetic Algorithm and Neural Network

Directory of Open Access Journals (Sweden)

M. Susmikanti

2015-12-01

Full Text Available In a nuclear industry area, high temperature treatment of materials is a factor which requires special attention. Assessment needs to be conducted on the properties of the materials used, including the strength of the materials. The measurement of material properties under thermal processes may reflect residual stresses. The use of Genetic Algorithm (GA to determine the optimal residual stress is one way to determine the strength of a material. In residual stress modeling with several parameters, it is sometimes difficult to solve for the optimal value through analytical or numerical calculations. Here, GA is an efficient algorithm which can generate the optimal values, both minima and maxima. The purposes of this research are to obtain the optimization of variable in residual stress models using GA and to predict the center of residual stress distribution, using fuzzy neural network (FNN while the artificial neural network (ANN used for modeling. In this work a single-material 316/316L stainless steel bar is modeled. The minimal residual stresses of the material at high temperatures were obtained with GA and analytical calculations. At a temperature of 6500C, the GA optimal residual stress estimation converged at –711.3689 MPa at adistance of 0.002934 mm from center point, whereas the analytical calculation result at that temperature and position is -975.556 MPa . At a temperature of 8500C, the GA result was -969.868 MPa at 0.002757 mm from the center point, while with analytical result was -1061.13 MPa. The difference in residual stress between GA and analytical results at a temperatureof6500C is about 27 %, while at 8500C it is 8.67 %. The distribution of residual stress showed a grouping concentrated around a coordinate of (-76; 76 MPa. The residuals stress model is a degree-two polynomial with coefficients of 50.33, -76.54, and -55.2, respectively, with a standard deviation of 7.874.

A Pseudomonas aeruginosa toxin that hijacks the host ubiquitin proteolytic system.

Directory of Open Access Journals (Sweden)

Jennifer M Bomberger

2011-03-01

Full Text Available Pseudomonas aeruginosa (P. aeruginosa is an opportunistic pathogen chronically infecting the lungs of patients with chronic obstructive pulmonary disease (COPD, pneumonia, cystic fibrosis (CF, and bronchiectasis. Cif (PA2934, a bacterial toxin secreted in outer membrane vesicles (OMV by P. aeruginosa, reduces CFTR-mediated chloride secretion by human airway epithelial cells, a key driving force for mucociliary clearance. The aim of this study was to investigate the mechanism whereby Cif reduces CFTR-mediated chloride secretion. Cif redirected endocytosed CFTR from recycling endosomes to lysosomes by stabilizing an inhibitory effect of G3BP1 on the deubiquitinating enzyme (DUB, USP10, thereby reducing USP10-mediated deubiquitination of CFTR and increasing the degradation of CFTR in lysosomes. This is the first example of a bacterial toxin that regulates the activity of a host DUB. These data suggest that the ability of P. aeruginosa to chronically infect the lungs of patients with COPD, pneumonia, CF, and bronchiectasis is due in part to the secretion of OMV containing Cif, which inhibits CFTR-mediated chloride secretion and thereby reduces the mucociliary clearance of pathogens.

Effects of rapeseed residue on lead and cadmium availability and uptake by rice plants in heavy metal contaminated paddy soil.

Science.gov (United States)

Ok, Yong Sik; Usman, Adel R A; Lee, Sang Soo; Abd El-Azeem, Samy A M; Choi, Bongsu; Hashimoto, Yohey; Yang, Jae E

2011-10-01

Rapeseed (Brassica napus L.) has been cultivated for biodiesel production worldwide. Winter rapeseed is commonly grown in the southern part of Korea under a rice-rapeseed double cropping system. In this study, a greenhouse pot experiment was conducted to assess the effects of rapeseed residue applied as a green manure alone or in combinations with mineral N fertilizer on Cd and Pb speciation in the contaminated paddy soil and their availability to rice plant (Oryza sativa L.). The changes in soil chemical and biological properties in response to the addition of rapeseed residue were also evaluated. Specifically, the following four treatments were evaluated: 100% mineral N fertilizer (N100) as a control, 70% mineral N fertilizer+rapeseed residue (N70+R), 30% mineral N fertilizer+rapeseed residue (N30+R) and rapeseed residue alone (R). The electrical conductivity and exchangeable cations of the rice paddy soil subjected to the R treatment or in combinations with mineral N fertilizer treatment, N70+R and N30+R, were higher than those in soils subjected to the N100 treatment. However, the soil pH value with the R treatment (pH 6.3) was lower than that with N100 treatment (pH 6.9). Use of rapeseed residue as a green manure led to an increase in soil organic matter (SOM) and enhanced the microbial populations in the soil. Sequential extraction also revealed that the addition of rapeseed residue decreased the easily accessible fraction of Cd by 5-14% and Pb by 30-39% through the transformation into less accessible fractions, thereby reducing metal availability to the rice plant. Overall, the incorporation of rapeseed residue into the metal contaminated rice paddy soils may sustain SOM, improve the soil chemical and biological properties, and decrease the heavy metal phytoavailability. Copyright © 2011 Elsevier Ltd. All rights reserved.

MARKET BASKET SURVEY FOR SOME PESTICIDES RESIDUES IN FRUITS AND VEGETABLES FROM GHANA

Directory of Open Access Journals (Sweden)

Crentsil Kofi Bempah

2012-12-01

Full Text Available A study was conducted to investigate the organochlorine, organophosphorus and synthetic pyrethroid pesticide residues in fruits and vegetables from markets in Ghana. For this purpose, a total of 309 fruits and vegetable samples, were collected and analyzed by gas chromatography with electron capture detector. The obtained results showed that the predominance of organochlorine followed by organophosphorus and synthetic pyrethroid pesticides in most of the analyzed samples. The detected concentrations of them were most significant in vegetable samples. The results obtained showed that 39.2 % of the fruits and vegetable samples analyzed contained no detectable level of the monitored pesticides, 51.0 % of the samples gave results with trace levels of pesticide residues below the maximum residue limit (MRL, while 9.8 % of the samples were above the MRL. The findings point to the urgent need to establish reliable monitoring programs for pesticides, so that any exceedance in concentration over environmental quality standards can be detected and appropriate actions taken.

Human airway epithelial cells investigated by atomic force microscopy: A hint to cystic fibrosis epithelial pathology

Energy Technology Data Exchange (ETDEWEB)

Lasalvia, Maria [Department of Clinical and Experimental Medicine, University of Foggia, Foggia (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari (Italy); Castellani, Stefano [Department of Medical and Surgical Sciences, University of Foggia, Foggia (Italy); D’Antonio, Palma [Department of Clinical and Experimental Medicine, University of Foggia, Foggia (Italy); Perna, Giuseppe [Department of Clinical and Experimental Medicine, University of Foggia, Foggia (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari (Italy); Carbone, Annalucia [Department of Medical and Surgical Sciences, University of Foggia, Foggia (Italy); Colia, Anna Laura; Maffione, Angela Bruna [Department of Clinical and Experimental Medicine, University of Foggia, Foggia (Italy); Capozzi, Vito [Department of Clinical and Experimental Medicine, University of Foggia, Foggia (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari (Italy); Conese, Massimo, E-mail: massimo.conese@unifg.it [Department of Medical and Surgical Sciences, University of Foggia, Foggia (Italy)

2016-10-15

The pathophysiology of cystic fibrosis (CF) airway disease stems from mutations in the CF Transmembrane Conductance Regulator (CFTR) gene, leading to a chronic respiratory disease. Actin cytoskeleton is disorganized in CF airway epithelial cells, likely contributing to the CF-associated basic defects, i.e. defective chloride secretion and sodium/fluid hypersorption. In this work, we aimed to find whether this alteration could be pointed out by means of Atomic Force Microscopy (AFM) investigation, as roughness and Young's elastic module. Moreover, we also sought to determine whether disorganization of actin cytoskeleton is linked to hypersoption of apical fluid. Not only CFBE41o- (CFBE) cells, immortalized airway epithelial cells homozygous for the F508del CFTR allele, showed a different morphology in comparison with 16HBE14o- (16HBE) epithelial cells, wild-type for CFTR, but also they displayed a lack of stress fibers, suggestive of a disorganized actin cytoskeleton. AFM measurements showed that CFBE cells presented a higher membrane roughness and decreased rigidity as compared with 16HBE cells. CFBE overexpressing wtCFTR became more elongated than the parental CFBE cell line and presented actin stress fibers. CFBE cells absorbed more fluid from the apical compartment. Study of fluid absorption with the F-actin-depolymerizing agent Latrunculin B demonstrated that actin cytoskeletal disorganization increased fluid absorption, an effect observed at higher magnitude in 16HBE than in CFBE cells. For the first time, we demonstrate that actin cytoskeleton disorganization is reflected by AFM parameters in CF airway epithelial cells. Our data also strongly suggest that the lack of stress fibers is involved in at least one of the early step in CF pathophysiology at the levels of the airways, i.e. fluid hypersorption. - Highlights: • CF bronchial epithelial (CFBE) cells show a disorganized actin cytoskeleton. • CFBE cells present high roughness and low rigidity in

Opening up of plasmalemma type-1 VDAC to form apoptotic "find me signal" pathways is essential in early apoptosis - evidence from the pathogenesis of cystic fibrosis resulting from failure of apoptotic cell clearance followed by sterile inflammation.

Science.gov (United States)

Thinnes, Friedrich P

2014-04-01

Cell membrane-standing type-1 VDAC is involved in cell volume regulation and thus apoptosis. The channel has been shown to figure as a pathway for osmolytes of varying classes, ATP included. An early event in apoptotic cell death is the release of "find me signals" by cells that enter the apoptotic process. ATP is one of those signals. Apoptotic cells this way attract phagocytes for an immunologically silent cell clearance. Thus, whenever apoptosis fails by a blockade of plasmalemma type-1 VDAC processes of sterile inflammation must be assumed for cell elimination. This is evident from a close look on the pathogenetic process of cystic fibrosis (CF). However, in normal airway epithelia two different anion channels cooperate to guarantee an appropriate volume of airway surface liquid (ASL) necessary for surface clearing: the cystic fibrosis conductance regulator (CFTR) and the outwardly rectifying chloride channel (ORCC) complex also called "alternate chloride channel" and under the control of the CFTR. There are arguments, that type-1 VDAC forms the channel part of the ORCC complex, and it has been shown that CFTR and type-1 VDAC co-localize in the apical membranes of human surface respiratory epithelium. In cystic fibrosis, the central cAMP-dependent regulation of ion and water transport via functional CFTR is lost. Here, CFTR molecules do not reach the apical membranes of airway epithelia anymore or work in an insufficient way, respectively. In addition, type-1 VDAC is no longer available to work as a "find me signal" pathway. In consequence, clearing away of apoptotic cells is blocked. There are experimental data on the channel characteristics of type-1 VDAC under the anion channel blocker DIDS (4,4-diisothiocyanato-stilbenedisulphonic acid) that argue in favor of this hypothesis. Together, type-1 VDAC should be kept as a "find me signal" pathway, which may give way to several classes of such signals. Copyright © 2014 Elsevier Inc. All rights reserved.

Human airway epithelial cells investigated by atomic force microscopy: A hint to cystic fibrosis epithelial pathology

International Nuclear Information System (INIS)

Lasalvia, Maria; Castellani, Stefano; D’Antonio, Palma; Perna, Giuseppe; Carbone, Annalucia; Colia, Anna Laura; Maffione, Angela Bruna; Capozzi, Vito; Conese, Massimo

2016-01-01

The pathophysiology of cystic fibrosis (CF) airway disease stems from mutations in the CF Transmembrane Conductance Regulator (CFTR) gene, leading to a chronic respiratory disease. Actin cytoskeleton is disorganized in CF airway epithelial cells, likely contributing to the CF-associated basic defects, i.e. defective chloride secretion and sodium/fluid hypersorption. In this work, we aimed to find whether this alteration could be pointed out by means of Atomic Force Microscopy (AFM) investigation, as roughness and Young's elastic module. Moreover, we also sought to determine whether disorganization of actin cytoskeleton is linked to hypersoption of apical fluid. Not only CFBE41o- (CFBE) cells, immortalized airway epithelial cells homozygous for the F508del CFTR allele, showed a different morphology in comparison with 16HBE14o- (16HBE) epithelial cells, wild-type for CFTR, but also they displayed a lack of stress fibers, suggestive of a disorganized actin cytoskeleton. AFM measurements showed that CFBE cells presented a higher membrane roughness and decreased rigidity as compared with 16HBE cells. CFBE overexpressing wtCFTR became more elongated than the parental CFBE cell line and presented actin stress fibers. CFBE cells absorbed more fluid from the apical compartment. Study of fluid absorption with the F-actin-depolymerizing agent Latrunculin B demonstrated that actin cytoskeletal disorganization increased fluid absorption, an effect observed at higher magnitude in 16HBE than in CFBE cells. For the first time, we demonstrate that actin cytoskeleton disorganization is reflected by AFM parameters in CF airway epithelial cells. Our data also strongly suggest that the lack of stress fibers is involved in at least one of the early step in CF pathophysiology at the levels of the airways, i.e. fluid hypersorption. - Highlights: • CF bronchial epithelial (CFBE) cells show a disorganized actin cytoskeleton. • CFBE cells present high roughness and low rigidity in the

Computing Decoupled Residuals for Compact Disc Players

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Stoustrup, Jakob; Andersen, Palle

2006-01-01

a pair of residuals generated by Compact Disc Player. However, these residuals depend on the performance of position servos in the Compact Disc Player. In other publications of the same authors a pair of decoupled residuals is derived. However, the computation of these alternative residuals has been...

Characterisation and management of concrete grinding residuals.

Science.gov (United States)

Kluge, Matt; Gupta, Nautasha; Watts, Ben; Chadik, Paul A; Ferraro, Christopher; Townsend, Timothy G

2018-02-01

Concrete grinding residue is the waste product resulting from the grinding, cutting, and resurfacing of concrete pavement. Potential beneficial applications for concrete grinding residue include use as a soil amendment and as a construction material, including as an additive to Portland cement concrete. Concrete grinding residue exhibits a high pH, and though not hazardous, it is sufficiently elevated that precautions need to be taken around aquatic ecosystems. Best management practices and state regulations focus on reducing the impact on such aquatic environment. Heavy metals are present in concrete grinding residue, but concentrations are of the same magnitude as typically recycled concrete residuals. The chemical composition of concrete grinding residue makes it a useful product for some soil amendment purposes at appropriate land application rates. The presence of unreacted concrete in concrete grinding residue was examined for potential use as partial replacement of cement in new concrete. Testing of Florida concrete grinding residue revealed no dramatic reactivity or improvement in mortar strength.

Carbaryl and monocrotophos residues in cottonseed products. Part of a coordinated programme on isotopic tracer-aided studies of chemical residues in cotton seed, feed, oil and related products

International Nuclear Information System (INIS)

Pablo, F.E.

1981-03-01

Cotton plants of Deltapine variety were treated with carbaryl (naphthyl-1- 14 C), (6.7 mg/plant) three times at two week intervals. Seeds were collected at maturity and 14 C-residues were determined in the oil and cake by standard procedures. 14 C-carbaryl and/or metabolite residues were 0.42 and 0.15 mg/kg in the crude oil and cake respectively. Parallel studies were conducted with spectrophotometric techniques using p-nitrobenzene diazonium fluoborate as chromogenic agent. Applications were made three times at a rate of 14 mg/plant. Residues in the crude oil and cake were found to be 0.83 and 0.04 mg/kg respectively. The higher residue level in the oil - compared to the radiometric technique - probably relates to higher application rates. Cotton plants of Deltapine variety were treated with (N-methyl- 14 C) monocrotophos (0.09 mg/plant) three times at two week intervals, as recommended for agricultural practice. Seeds were collected at maturity and standard procedures for extraction, clean-up and paper and thin-layer chromatography were adopted for the ultimate determination of residues in seed, oil and cake. Parallel experiments, using spectrophotometric techniques, were made for comparison. 14 C-residues of monocrotophos and/or metabolites in cottonseed, crude oil and cake were found to be 0.06, 0.12 and 0.05 mg/kg respectively. Corresponding data obtained by non-nuclear techniques were 0.18, 0.42 and 0.15 mg/kg respectively. The discrepancy between the two sets of results may be related to different rates of application: 0.3 mg and 0.09 mg/plant for non-nuclear and radiometric techniques respectively. Among the major metabolites identified in the cottonseed were dimethyl phosphate and O-desmethyl monocrotophos. N-demethylated monocrotophos and sugar conjugates were also identified

Evaluation and optimization of nutritional and environmental impact of biogas residues; Bewertung und Optimierung der Naehrstoff- und Umweltwirkung von Gaerrueckstaenden aus der Biogasgewinnung

Energy Technology Data Exchange (ETDEWEB)

Lichti, Fabian Heribert

2013-04-29

On the basis of the dynamic growth of biogas plants in Germany the fertilization with biogas residues has obtained an important role for recirculation of plant nutrients, particularly with regard to nitrogen. In this work the effect of N nutrition with biogas residues was assessed in a 3-year on-field trial conducted at four sites throughout Bavaria. The fertilizing effects were tested by varying rate and time of biogas residues application, using different application techniques and the addition of nitrification inhibitors on several crops. The biogas residues achieved mineral fertilizer equivalents of 30 - 45 %. Overall, the untreated biogas residues showed a slightly increased N efficiency compared to cattle manure, whereas particularly site-dependent differences resulted in large differences in N efficiency of biogas residues.

Residual symptoms and functioning in depression, does the type of residual symptom matter? A post-hoc analysis

Directory of Open Access Journals (Sweden)

Romera Irene

2013-02-01

Full Text Available Abstract Background The degrees to which residual symptoms in major depressive disorder (MDD adversely affect patient functioning is not known. This post-hoc analysis explored the association between different residual symptoms and patient functioning. Methods Patients with MDD who responded (≥50% on the 17-item Hamilton Rating Scale for Depression; HAMD-17 after 3 months of treatment (624/930 were included. Residual core mood-symptoms (HAMD-17 core symptom subscale ≥1, residual insomnia-symptoms (HAMD-17 sleep subscale ≥1, residual anxiety-symptoms (HAMD-17-anxiety subscale ≥1, residual somatic-symptoms (HAMD-17 Item 13 ≥1, pain (Visual Analogue Scale ≥30, and functioning were assessed after 3 months treatment. A stepwise logistic regression model with normal functioning (Social and Occupational Functioning Assessment Scale ≥80 as the dependent variable was used. Results After 3 months, 59.5% of patients (371/624 achieved normal functioning and 66.0% (412/624 were in remission. Residual symptom prevalence was: core mood symptoms 72%; insomnia 63%; anxiety 78%; and somatic symptoms 41%. Pain reported in 18%. Factors associated with normal functioning were absence of core mood symptoms (odds ratio [OR] 8.7; 95% confidence interval [CI], 4.6–16.7, absence of insomnia symptoms (OR 1.8; 95% CI, 1.2–2.7, episode length (4–24 weeks vs. ≥24 weeks [OR 2.0; 95% CI, 1.1–3.6] and better baseline functioning (OR 1.0; 95% CI, 1.0–1.1. A significant interaction between residual anxiety symptoms and pain was found (p = 0.0080. Conclusions Different residual symptoms are associated to different degrees with patient functioning. To achieve normal functioning, specific residual symptoms domains might be targeted for treatment.

Nitrogen availability of biogas residues

Energy Technology Data Exchange (ETDEWEB)

El-Sayed Fouda, Sara

2011-09-07

The objectives of this study were to characterize biogas residues either unseparated or separated into a liquid and a solid phase from the fermentation of different substrates with respect to their N and C content. In addition, short and long term effects of the application of these biogas residues on the N availability and N utilization by ryegrass was investigated. It is concluded that unseparated or liquid separated biogas residues provide N at least corresponding to their ammonium content and that after the first fertilizer application the C{sub org}:N{sub org} ratio of the biogas residues was a crucial factor for the N availability. After long term application, the organic N accumulated in the soil leads to an increased release of N.

Composite Cure Process Modeling and Simulations using COMPRO(Registered Trademark) and Validation of Residual Strains using Fiber Optics Sensors

Science.gov (United States)

Sreekantamurthy, Thammaiah; Hudson, Tyler B.; Hou, Tan-Hung; Grimsley, Brian W.

2016-01-01

Composite cure process induced residual strains and warping deformations in composite components present significant challenges in the manufacturing of advanced composite structure. As a part of the Manufacturing Process and Simulation initiative of the NASA Advanced Composite Project (ACP), research is being conducted on the composite cure process by developing an understanding of the fundamental mechanisms by which the process induced factors influence the residual responses. In this regard, analytical studies have been conducted on the cure process modeling of composite structural parts with varied physical, thermal, and resin flow process characteristics. The cure process simulation results were analyzed to interpret the cure response predictions based on the underlying physics incorporated into the modeling tool. In the cure-kinetic analysis, the model predictions on the degree of cure, resin viscosity and modulus were interpreted with reference to the temperature distribution in the composite panel part and tool setup during autoclave or hot-press curing cycles. In the fiber-bed compaction simulation, the pore pressure and resin flow velocity in the porous media models, and the compaction strain responses under applied pressure were studied to interpret the fiber volume fraction distribution predictions. In the structural simulation, the effect of temperature on the resin and ply modulus, and thermal coefficient changes during curing on predicted mechanical strains and chemical cure shrinkage strains were studied to understand the residual strains and stress response predictions. In addition to computational analysis, experimental studies were conducted to measure strains during the curing of laminated panels by means of optical fiber Bragg grating sensors (FBGs) embedded in the resin impregnated panels. The residual strain measurements from laboratory tests were then compared with the analytical model predictions. The paper describes the cure process

Residual stresses around Vickers indents

International Nuclear Information System (INIS)

Pajares, A.; Guiberteau, F.; Steinbrech, R.W.

1995-01-01

The residual stresses generated by Vickers indentation in brittle materials and their changes due to annealing and surface removal were studied in 4 mol% yttria partially stabilized zirconia (4Y-PSZ). Three experimental methods to gain information about the residual stress field were applied: (i) crack profile measurements based on serial sectioning, (ii) controlled crack propagation in post indentation bending tests and (iii) double indentation tests with smaller secondary indents located around a larger primary impression. Three zones of different residual stress behavior are deduced from the experiments. Beneath the impression a crack free spherical zone of high hydrostatic stresses exists. This core zone is followed by a transition regime where indentation cracks develop but still experience hydrostatic stresses. Finally, in an outward third zone, the crack contour is entirely governed by the tensile residual stress intensity (elastically deformed region). Annealing and surface removal reduce this crack driving stress intensity. The specific changes of the residual stresses due to the post indentation treatments are described and discussed in detail for the three zones

Minimization of zirconium chlorinator residues

International Nuclear Information System (INIS)

Green, G.K.; Harbuck, D.D.

1995-01-01

Zirconium chlorinator residues contain an array of rare earths, scandium, unreacted coke, and radioactive thorium and radium. Because of the radioactivity, the residues must be disposed in special waste containment facilities. As these sites become more congested, and with stricter environmental regulations, disposal of large volumes of wastes may become more difficult. To reduce the mass of disposed material, the US Bureau of Mines (USBM) developed technology to recover rare earths, thorium and radium, and unreacted coke from these residues. This technology employs an HCl leach to solubilize over 99% of the scandium and thorium, and over 90% of the rare earths. The leach liquor is processed through several solvent extraction stages to selectively recover scandium, thorium, and rare earths. The leach residue is further leached with an organic acid to solubilize radium, thus allowing unreacted coke to be recycled to the chlorinator. The thorium and radium waste products, which comprise only 2.1% of the original residue mass, can then be sent to the radioactive waste facility

9 CFR 311.39 - Biological residues.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Biological residues. 311.39 Section... Biological residues. Carcasses, organs, or other parts of carcasses of livestock shall be condemned if it is determined that they are adulterated because of the presence of any biological residues. ...

Hanford Tank 241-C-106: Impact of Cement Reactions on Release of Contaminants from Residual Waste

International Nuclear Information System (INIS)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2006-01-01

The CH2M HILL Hanford Group, Inc. (CH2M HILL) is producing risk/performance assessments to support the closure of single-shell tanks at the U.S. Department of Energy's Hanford Site. As part of this effort, staff at Pacific Northwest National Laboratory were asked to develop release models for contaminants of concern that are present in residual sludge remaining in tank 241-C-106 (C-106) after final retrieval of waste from the tank. Initial work to produce release models was conducted on residual tank sludge using pure water as the leaching agent. The results were reported in an earlier report. The decision has now been made to close the tanks after waste retrieval with a cementitious grout to minimize infiltration and maintain the physical integrity of the tanks. This report describes testing of the residual waste with a leaching solution that simulates the composition of water passing through the grout and contacting the residual waste at the bottom of the tank.

Exposure of the Public from Large Deposits of Mineral Residues

International Nuclear Information System (INIS)

2011-06-01

mineral processing, it has been suggested that case by case evaluation of the dose may be required. It was therefore decided to conduct further investigations of the doses expected to be received as a result of exposure of members of the public to a large NORM residue deposit, with consideration being given to all potentially significant exposure pathways including those involving contamination of water. The investigations were conducted using an evidence based approach involving the review of available information from real world examples of actual NORM residue deposits, as well as a calculation approach involving the modelling of radionuclide migration from a 'representative' large NORM residue deposit.

Residual-stress measurements

Energy Technology Data Exchange (ETDEWEB)

Ezeilo, A N; Webster, G A [Imperial College, London (United Kingdom); Webster, P J [Salford Univ. (United Kingdom)

1997-04-01

Because neutrons can penetrate distances of up to 50 mm in most engineering materials, this makes them unique for establishing residual-stress distributions non-destructively. D1A is particularly suited for through-surface measurements as it does not suffer from instrumental surface aberrations commonly found on multidetector instruments, while D20 is best for fast internal-strain scanning. Two examples for residual-stress measurements in a shot-peened material, and in a weld are presented to demonstrate the attractive features of both instruments. (author).

Identification of the CFTR c.1666A>G Mutation in Hereditary Inclusion Body Myopathy Using Next-Generation Sequencing Analysis

Directory of Open Access Journals (Sweden)

Yan Lu

2018-05-01

Full Text Available Hereditary inclusion body myopathy (HIBM is a rare autosomal recessive adult onset muscle disease which affects one to three individuals per million worldwide. This disease is autosomal dominant and occurs in adulthood. Our previous study reported a new subtype of HIBM linked to the susceptibility locus at 7q22.1-31.1. The present study is aimed to identify the candidate gene responsible for the phenotype in HIBM pedigree. After multipoint linkage analysis, we performed targeted capture sequencing on 16 members and whole-exome sequencing (WES on 5 members. Bioinformatics filtering was performed to prioritize the candidate pathogenic gene variants, which were further genotyped by Sanger sequencing. Our results showed that the highest peak of LOD score (4.70 was on chromosome 7q22.1-31.1.We identified 2 and 22 candidates using targeted capture sequencing and WES respectively, only one of which as CFTRc.1666A>G mutation was well cosegregated with the HIBM phenotype. Using transcriptome analysis, we did not detect the differences of CFTR's mRNA expression in the proband compared with healthy members. Due to low incidence of HIBM and there is no other pedigree to assess, mutation was detected in three patients with duchenne muscular dystrophyn (DMD and five patients with limb-girdle muscular dystrophy (LGMD. And we found that the frequency of mutation detected in DMD and LGMD patients was higher than that of being expected in normal population. We suggested that the CFTRc.1666A>G may be a candidate marker which has strong genetic linkage with the causative gene in the HIBM family.

Part 1: Logging residues in piles - Needle loss and fuel quality. Part 2: Nitrogen leaching under piles of logging residues

International Nuclear Information System (INIS)

Lehtikangas, P.; Lundkvist, H.

1991-01-01

Part 1: Experimental piles were built in three geographical locations during May-Sept. 1989. Logging residues consisted of 95% spruce and 5% pine. Height of the piles varied between 80 and 230 cm. Needles were collected by placing drawers under 40 randomely chosen piles. The drawers were emptied every two weeks during the storage period. Natural needle loss was between 18 and 32% of the total amount of needles after the first two months of storage. At the end of the storage period, 24-42% of the needles had fallen down to the drawers. At the end of the experiment the total needle fall was 95-100% in the shaken piles. According to the results of this study piles smaller than 150 cm had the most effective needle fall. Piles should be placed on open places where the air and sun heat penetrate and dry them. Needles were the most sensitive fraction to variations in precipitation compared to the other components, such as branches. Piles usually dried quickly, but they also rewet easily. This was especially true in the smaller piles. The lowest moisture content was measured at the end of June. The ash content in needles varied between 4 and 8%. 16 refs., 15 figs. Part 2: Three field experiments were equipped with no-tension humus lysimeters. Pairs of lysimeters with the same humus/field layer vegetation material were placed in pairs, one under a pile of felling residues and another in the open clear felling. Leaching of nitrogen as well as pH and electric conductivity in the leachate was followed through sampling of the leachate at regular intervals. The results from the investigation show that: * the amount of leachate was higher in lysimeters in the open clear felling, * pH in the leachate was initially lower under piles of felling residues, * the amount of nitrogen leached was higher in the open clear felling. Thus, storing of felling residues in piles during the summer season did not cause any increase in nitrogen leaching, which had been considered to be a risk

Residues from waste incineration. Final report

Energy Technology Data Exchange (ETDEWEB)

Astrup, T.; Juul Pedersen, A.; Hyks, J.; Frandsen, F.J.

2009-08-15

The overall objective of the project was to improve the understanding of the formation and characteristics of residues from waste incineration. This was done focusing on the importance of the waste input and the operational conditions of the furnace. Data and results obtained from the project have been discussed in this report according to the following three overall parts: i) mass flows and element distribution, ii) flue gas/particle partitioning and corrosion/deposition aspects, and iii) residue leaching. This has been done with the intent of structuring the discussion while tacitly acknowledging that these aspects are interrelated and cannot be separated. Overall, it was found that the waste input composition had significant impact of the characteristics of the generated residues. A similar correlation between operational conditions and residue characteristics could not be observed. Consequently, the project recommend that optimization of residue quality should focus on controlling the waste input composition. The project results showed that including specific waste materials (and thereby also excluding the same materials) may have significant effects on the residue composition, residue leaching, aerosol and deposit formation.It is specifically recommended to minimize Cl in the input waste. Based on the project results, it was found that a significant potential for optimization of waste incineration exist. (author)

Pesticide Residues, Results from the period 2004-2011

DEFF Research Database (Denmark)

Petersen, Annette; Jensen, Bodil Hamborg; Andersen, Jens Hinge

The present report presents the results from the 2004-2011 period of the monitoring programmes conducted by The Danish Veterinary and Food Administration. The programmes included commodities of fruit, vegetable, cereals and animal origin using random sampling from food on the Danish market. Since...... the beginning of the 1960, Denmark has monitored fruit and vegetables for pesticides residues. For the periods 1993-1997 and 1998-2003, results were collated and the dietary exposure was calculated. In this report data for the analyses carried out in the period 2004-2011 are reported as well as the exposure...

Ensemble Kalman filtering with residual nudging

KAUST Repository

Luo, X.

2012-10-03

Covariance inflation and localisation are two important techniques that are used to improve the performance of the ensemble Kalman filter (EnKF) by (in effect) adjusting the sample covariances of the estimates in the state space. In this work, an additional auxiliary technique, called residual nudging, is proposed to monitor and, if necessary, adjust the residual norms of state estimates in the observation space. In an EnKF with residual nudging, if the residual norm of an analysis is larger than a pre-specified value, then the analysis is replaced by a new one whose residual norm is no larger than a pre-specified value. Otherwise, the analysis is considered as a reasonable estimate and no change is made. A rule for choosing the pre-specified value is suggested. Based on this rule, the corresponding new state estimates are explicitly derived in case of linear observations. Numerical experiments in the 40-dimensional Lorenz 96 model show that introducing residual nudging to an EnKF may improve its accuracy and/or enhance its stability against filter divergence, especially in the small ensemble scenario.

Determination of Pesticides Residues in Cucumbers Grown in Greenhouse and the Effect of Some Procedures on Their Residues.

Science.gov (United States)

Leili, Mostafa; Pirmoghani, Amin; Samadi, Mohammad Taghi; Shokoohi, Reza; Roshanaei, Ghodratollah; Poormohammadi, Ali

2016-11-01

The objective of this study was to determine the residual concentrations of ethion and imidacloprid in cucumbers grown in greenhouse. The effect of some simple processing procedures on both ethion and imidacloprid residues were also studied. Ten active greenhouses that produce cucumber were randomly selected. Ethion and imidacloprid as the most widely used pesticides were measured in cucumber samples of studied greenhouses. Moreover, the effect of storing, washing, and peeling as simple processing procedures on both ethion and imidacloprid residues were investigated. One hour after pesticide application; the maximum residue levels (MRLs) of ethion and imidacloprid were higher than that of Codex standard level. One day after pesticide application, the levels of pesticides were decreased about 35 and 31% for ethion and imidacloprid, respectively, which still were higher than the MRL. Washing procedure led to about 51 and 42.5% loss in ethion and imidacloprid residues, respectively. Peeling procedure also led to highest loss of 93.4 and 63.7% in ethion and imidacloprid residues, respectively. The recovery for both target analytes was in the range between 88 and 102%. The residue values in collected samples one hour after pesticides application were higher than standard value. The storing, washing, and peeling procedures lead to the decrease of pesticide residues in greenhouse cucumbers. Among them, the peeling procedure has the greatest impact on residual reduction. Therefore, these procedures can be used as simple and effective processing techniques for reducing and removing pesticides from greenhouse products before their consumption.

The CF-CIRC study: a French collaborative study to assess the accuracy of Cystic Fibrosis diagnosis in neonatal screening

Directory of Open Access Journals (Sweden)

Bellon Gabriel

2006-10-01

Full Text Available Abstract Background Cystic fibrosis (CF is caused by mutations in the gene encoding for the CF transmembrane conductance regulator (CFTR protein, which acts as a chloride channel after activation by cyclic AMP (cAMP. Newborn screening programs for CF usually consist of an immunoreactive trypsinogen (IRT assay, followed when IRT is elevated by testing for a panel of CF-causing mutations. Some children, however, may have persistent hypertrypsinogenemia, only one or no identified CFTR gene mutation, and sweat chloride concentrations close to normal values. In vivo demonstration of abnormal CFTR protein function would be an important diagnostic aid in this situation. Measurements of transepithelial nasal potential differences (NPD in adults accurately characterize CFTR-related ion transport. The aim of the present study is to establish reference values for NPD measurements for healthy children and those with CF aged 3 months to 3 years, the age range of most difficult-to-diagnose patients with suspected CF. The ultimate goal of our study is to validate NPD testing as a diagnostic tool for children with borderline results in neonatal screening. Methods/Design We adapted the standard NPD protocol for young children, designed a special catheter for them, used a slower perfusion rate, and shortened the protocol to include only measurement of basal PD, transepithelial sodium (Na+ transport in response to the Na+ channel inhibitor amiloride, and CFTR-mediated chloride (Cl- secretion in response to isoproterenol, a β-agonist in a Cl- free solution. The study will include 20 children with CF and 20 healthy control children. CF children will be included only if they carry 2 CF-causing mutations in the CFTR gene or have sweat chloride concentrations > 60 mEq/L or both. The healthy children will be recruited among the siblings of the CF patients, after verification that they do not carry the familial mutation. Discussion A preliminary study of 3 adult control

Variation behavior of residual stress distribution by manufacturing processes in welded pipes of austenitic stainless steel

International Nuclear Information System (INIS)

Ihara, Ryohei; Hashimoto, Tadafumi; Mochizuki, Masahito

2012-01-01

Stress corrosion cracking (SCC) has been observed near heat affected zone (HAZ) of primary loop recirculation pipes made of low-carbon austenitic stainless steel type 316L in the nuclear power plants. For the non-sensitization material, residual stress is the important factor of SCC, and it is generated by machining and welding. In the actual plants, welding is conducted after machining as manufacturing processes of welded pipes. It could be considered that residual stress generated by machining is varied by welding as a posterior process. This paper presents residual stress variation due to manufacturing processes of pipes using X-ray diffraction method. Residual stress distribution due to welding after machining had a local maximum stress in HAZ. Moreover, this value was higher than residual stress generated by welding or machining. Vickers hardness also had a local maximum hardness in HAZ. In order to clarify hardness variation, crystal orientation analysis with EBSD method was performed. Recovery and recrystallization were occurred by welding heat near the weld metal. These lead hardness decrease. The local maximum region showed no microstructure evolution. In this region, machined layer was remained. Therefore, the local maximum hardness was generated at machined layer. The local maximum stress was caused by the superposition effect of residual stress distributions due to machining and welding. Moreover, these local maximum residual stress and hardness are exceeded critical value of SCC initiation. In order to clarify the effect of residual stress on SCC initiation, evaluation including manufacturing processes is important. (author)

Cystic Fibrosis Gene Therapy in the UK and Elsewhere

Science.gov (United States)

Pytel, Kamila M.; Alton, Eric W.F.W.

2015-01-01

Abstract The cystic fibrosis transmembrane conductance regulator (CFTR) gene was identified in 1989. This opened the door for the development of cystic fibrosis (CF) gene therapy, which has been actively pursued for the last 20 years. Although 26 clinical trials involving approximately 450 patients have been carried out, the vast majority of these trials were short and included small numbers of patients; they were not designed to assess clinical benefit, but to establish safety and proof-of-concept for gene transfer using molecular end points such as the detection of recombinant mRNA or correction of the ion transport defect. The only currently published trial designed and powered to assess clinical efficacy (defined as improvement in lung function) administered AAV2-CFTR to the lungs of patients with CF. The U.K. Cystic Fibrosis Gene Therapy Consortium completed, in the autumn of 2014, the first nonviral gene therapy trial designed to answer whether repeated nonviral gene transfer (12 doses over 12 months) can lead to clinical benefit. The demonstration that the molecular defect in CFTR can be corrected with small-molecule drugs, and the success of gene therapy in other monogenic diseases, is boosting interest in CF gene therapy. Developments are discussed here. PMID:25838137

The lamellae-free-type pseudobranch of the euryhaline milkfish (Chanos chanos) is a Na(+), K(+)-ATPase-abundant organ involved in hypoosmoregulation.

Science.gov (United States)

Yang, Sheng-Hui; Kang, Chao-Kai; Kung, Hsiu-Ni; Lee, Tsung-Han

2014-04-01

In teleosts, the pseudobranch is hemibranchial, with a gill-like structure located near the first gill. We hypothesized that the pseudobranch of the milkfish might exhibit osmoregulatory ability similar to that of the gills. In this study, the obtained Na(+), K(+)-ATPase (NKA) activity and protein abundance profiles showed that these parameters were higher in the pseudobranchs of the seawater (SW)- than the freshwater (FW)-acclimated milkfish, opposite the situation in the gills. The pseudobranch of the milkfish contained two types of NKA-immunoreactive cells, chloride cells (CCs) and pseudobranch-type cells (PSCs). To further clarify the roles of CCs and PSCs in the pseudobranch, we investigated the distributions of two ion transporters: the Na(+), K(+), 2Cl(-) cotransporter (NKCC) and the cystic fibrosis transmembrane conductance regulator (CFTR). NKCC on the basolateral membrane and CFTR on the apical membrane were found only in pseudobranchial CCs of SW-acclimated individuals. Taken together, the results distinguished NKA-IR CCs and PSCs in the pseudobranch of milkfish using antibodies against NKCC and CFTR as markers. In addition, increases in the numbers and sizes of CCs as well as in NKA expression observed upon salinity challenge indicated the potential roles of pseudobranchs in hypo-osmoregulation in this euryhaline teleost. Copyright © 2014 Elsevier Inc. All rights reserved.

Alternatives to crop residues for soil amendment

OpenAIRE

Powell, J.M.; Unger, P.W.

1997-01-01

Metadata only record In semiarid agroecosystems, crop residues can provide important benefits of soil and water conservation, nutrient cycling, and improved subsequent crop yields. However, there are frequently multiple competing uses for residues, including animal forage, fuel, and construction material. This chapter discusses the various uses of crop residues and examines alternative soil amendments when crop residues cannot be left on the soil.

A Robust Transform Estimator Based on Residual Analysis and Its Application on UAV Aerial Images

Directory of Open Access Journals (Sweden)

Guorong Cai

2018-02-01

Full Text Available Estimating the transformation between two images from the same scene is a fundamental step for image registration, image stitching and 3D reconstruction. State-of-the-art methods are mainly based on sorted residual for generating hypotheses. This scheme has acquired encouraging results in many remote sensing applications. Unfortunately, mainstream residual based methods may fail in estimating the transform between Unmanned Aerial Vehicle (UAV low altitude remote sensing images, due to the fact that UAV images always have repetitive patterns and severe viewpoint changes, which produce lower inlier rate and higher pseudo outlier rate than other tasks. We performed extensive experiments and found the main reason is that these methods compute feature pair similarity within a fixed window, making them sensitive to the size of residual window. To solve this problem, three schemes that based on the distribution of residuals are proposed, which are called Relational Window (RW, Sliding Window (SW, Reverse Residual Order (RRO, respectively. Specially, RW employs a relaxation residual window size to evaluate the highest similarity within a relaxation model length. SW fixes the number of overlap models while varying the length of window size. RRO takes the permutation of residual values into consideration to measure similarity, not only including the number of overlap structures, but also giving penalty to reverse number within the overlap structures. Experimental results conducted on our own built UAV high resolution remote sensing images show that the proposed three strategies all outperform traditional methods in the presence of severe perspective distortion due to viewpoint change.

77 FR 24671 - Compliance Guide for Residue Prevention and Agency Testing Policy for Residues

Science.gov (United States)

2012-04-25

... Hazard Analysis and Critical Control Points (HACCP) inspection system, another important component of the NRP is to provide verification of residue control in HACCP systems. As part of the HACCP regulation... guide, and FSIS finds violative residues, the establishment's HACCP system may be inadequate under 9 CFR...

The Effects of Rape Residue Mulching on Net Global Warming Potential and Greenhouse Gas Intensity from No-Tillage Paddy Fields

Science.gov (United States)

Zhang, Zhi-Sheng; Cao, Cou-Gui; Guo, Li-Jin; Li, Cheng-Fang

2014-01-01

A field experiment was conducted to provide a complete greenhouse gas (GHG) accounting for global warming potential (GWP), net GWP, and greenhouse gas intensity (GHGI) from no-tillage (NT) paddy fields with different amounts of oilseed rape residue mulch (0, 3000, 4000, and 6000 kg dry matter (DM) ha−1) during a rice-growing season after 3 years of oilseed rape-rice cultivation. Residue mulching treatments showed significantly more organic carbon (C) density for the 0–20 cm soil layer at harvesting than no residue treatment. During a rice-growing season, residue mulching treatments sequestered significantly more organic C from 687 kg C ha−1 season−1 to 1654 kg C ha−1 season−1 than no residue treatment. Residue mulching significantly increased emissions of CO2 and N2O but decreased CH4 emissions. Residue mulching treatments significantly increased GWP by 9–30% but significantly decreased net GWP by 33–71% and GHGI by 35–72% relative to no residue treatment. These results suggest that agricultural economic viability and GHG mitigation can be achieved simultaneously by residue mulching on NT paddy fields in central China. PMID:25140329

Decolorization of textile industry wastewater in solid state fermentation with Peach-Palm (Bactris gasipaes residue

Directory of Open Access Journals (Sweden)

J. A. Chicatto

2018-02-01

Full Text Available Abstract In this work we have assessed the decolorization of textile effluents throughout their treatment in a solid-state fermentation (SSF system. SSF assays were conducted with peach-palm (Bactris gasipaes residue using the white rot fungus Ganoderma lucidum EF 31. The influence of the dye concentration and of the amounts of peach-palm residue and liquid phase on both the discoloration efficiency and enzyme production was studied. According to our results, independently of experimental conditions employed, laccase was the main ligninolytic enzyme produced by G. lucidum. The highest laccase activity was obtained at very low effluent concentrations, suggesting the existence of an inhibitory effect of higher concentrations on fungal metabolism. The highest percentage of color removal was reached when 10 grams of peach palm residue was moistened with 60 mL of the final effluent. In control tests carried out with the synthetic dye Remazol Brilliant Blue R (RBBR decolorization efficiencies about 20% higher than that achieved with the industrial effluent were achieved. The adsorption of RBBR on peach-palm residue was also investigated. Equilibrium tests showed that the adsorption of this dye followed both Langmuir and Freundlich isotherms. Hence, our experimental results indicate that peach-palm residue is suitable substrate for both laccase production and color removal in industrial effluents.

Decolorization of textile industry wastewater in solid state fermentation with Peach-Palm (Bactris gasipaes) residue.

Science.gov (United States)

Chicatto, J A; Rainert, K T; Gonçalves, M J; Helm, C V; Altmajer-Vaz, D; Tavares, L B B

2018-02-15

In this work we have assessed the decolorization of textile effluents throughout their treatment in a solid-state fermentation (SSF) system. SSF assays were conducted with peach-palm (Bactris gasipaes) residue using the white rot fungus Ganoderma lucidum EF 31. The influence of the dye concentration and of the amounts of peach-palm residue and liquid phase on both the discoloration efficiency and enzyme production was studied. According to our results, independently of experimental conditions employed, laccase was the main ligninolytic enzyme produced by G. lucidum. The highest laccase activity was obtained at very low effluent concentrations, suggesting the existence of an inhibitory effect of higher concentrations on fungal metabolism. The highest percentage of color removal was reached when 10 grams of peach palm residue was moistened with 60 mL of the final effluent. In control tests carried out with the synthetic dye Remazol Brilliant Blue R (RBBR) decolorization efficiencies about 20% higher than that achieved with the industrial effluent were achieved. The adsorption of RBBR on peach-palm residue was also investigated. Equilibrium tests showed that the adsorption of this dye followed both Langmuir and Freundlich isotherms. Hence, our experimental results indicate that peach-palm residue is suitable substrate for both laccase production and color removal in industrial effluents.

Residual stress improvement for pipe weld by means of induction heating pre-flawed pipe

International Nuclear Information System (INIS)

Umemoto, T.; Yoshida, K.; Okamoto, A.

1980-01-01

The intergranular stress corrosion cracking (IGSCC) has been found in type 304 stainless steel piping of several BWR plants. It is already well known that IGSCC is most likely to occur when three essential factors, material sensitization, high tensile stress and corrosive environment, are present. If the welding residual stress is sufficiently high (200 to approximately 400 MPa) in the inside piping surface near the welded joint, then it may be one of the biggest contributors to IGSCC. If the residual stress is reduced or reversed by some way, the IGSCC will be effectively mitigated. In this paper a method to improve the residual stress named IHSI (Induction Heating Stress Improvement) is explained. IHSI aims to improve the condition of residual stress in the inside pipe surface using the thermal stress induced by the temperature difference in pipe wall, that is produced when the pipe is heated from the outside surface by an induction heating coil and cooled on the inside surface by water simultaneously. This method becomes more attractive when it can be successfully applied to in-service piping which might have some pre-flaw. In order to verify the validity of IHSI for such piping, some experiments and calculations using finite element method were conducted. These results are mainly discussed in this paper from the view-points of residual stress, flaw behaviour during IHSI and material deterioration. (author)

Effects of residual stress on fatigue strength of small diameter welded pipe joint

International Nuclear Information System (INIS)

Yamashita, Tetsuo; Hattori, Takahiro; Nomoto, Toshiharu; Iida, Kunihiro; Sato, Masanobu

1996-01-01

A power plant consists of many welded components, therefore, it is essential in establishing the reliability of the power plant to maintain the reliability of all welded components. The fatigue failure caused by mechanical vibrations of small diameter welded joints, which is represented by socket welded joints, is one of the major causes of trouble for the welded parts of the power plant. Here, bending fatigue tests were conducted to investigate the fatigue strength of small diameter socket welded pipe joints. In the most cases of large diameter socket joints, a fatigue crack started from the root of the fillet weld though the stress amplitude at the root was smaller than that at the toe of fillet weld. Additionally, the fatigue strength was affected by the weld bead sequence. The residual stress was considered to be one of the important parameters governing fatigue strength, therefore, its effects were investigated. In several types of pipe joints, the local stress and residual stress distributions were calculated by finite element analysis. The residual stresses were compressive at the toe and tensile at the root of the socket welded joints. Based on these results, the effects of residual stresses on the fatigue strength are discussed for small diameter welded pipe joints in the present work

Study of residual stresses in welded joints of dual phase HSLA steel used in automotive industry

International Nuclear Information System (INIS)

Barbato, D.S.; Fonseca, M.P. Cindra; Marques Junior, A.S.; Chuvas, T.C.; Pardal, J.M.

2010-01-01

One way of weight reduction in automotive vehicles is through the use of high strength and low alloy (HSLA) steels, which enables the use of small thickness plates. Whereas the appearance of residual stresses is intrinsic to the welding process, this study evaluates the residual stresses generated in welded joints obtained by TIG and LASER welding processes and comparing them. Residual stresses were measured by X-rays diffraction technique, using a portable device with Crκα radiation applying the double exposure method. It also evaluates the influence of shot peening treatment applied after welding, in the bend tests conducted for both welding conditions and TIG welded joints showed higher stability of compressive stresses after welding. The metallographic analysis by optical microscopy complemented the welded joints characterization. (author)

Investigation of antibiotic residues in edible tissues of slaughtered broilers in Maragheh abattoir using FPT method (short comunication

Directory of Open Access Journals (Sweden)

Masumeh Abasi

2016-05-01

Full Text Available Antibiotic residues in food stuff and their transmission to the consumers have some consequences such as bacterial resistance, allergic reactions, intoxication, carcinogenic effects and disturbing of intestine natural flora. Among microbiologic methods, four plate test (FPT is used to detect antibiotic residues in food stuff, which performs in four culture media with different pH values and test bacteria. The aim of this study was investigation of antibiotic residues in edible tissues of slaughtered broilers in Maragheh abattoir using FPT method. For this reason, 40 slaughtered broilers carcasses in Maragheh abattoir (from 10 different poultry farms were sampled. The sampling was conducted randomly from breast and leg muscles, gizzard as well as liver of each carcass. According to results of current study, 60% of liver samples, 55% of leg samples, 52.5% of breast samples and 52.5% of gizzard samples contained antibiotic residues. Moreover, the amount of antibiotic residues among different samples did not show statistical significance (p>0.05. The highest occurrence of antibiotic residue was found in two flocks (100% and the lowest occurrence was recorded for another two flocks (0%. According to the health hazard of antibiotic residues in foods, continuous monitoring is recommended for edible tissues of broilers.

Airway Clearance Techniques (ACTs)

Medline Plus

Full Text Available ... Research Consortia CF Biomarker Consortium CFTR 3-D Structure Consortium CFTR Folding Consortium Epithelial Stem Cell Consortium Mucociliary Clearance Consortium SUCCESS WITH THERAPIES RESEARCH ...

Biodiesel production from residual oils recovered from spent bleaching earth

International Nuclear Information System (INIS)

Huang, Yi-Pin; Chang, James I.

2010-01-01

This work was to study technical and economic feasibilities of converting residual oils recovered from spent bleaching earth generated at soybean oil refineries into useable biodiesel. Experimental results showed that fatty acids in the SBE residual oil were hexadecenoic acid (58.19%), stearic acid (21.49%) and oleic acid (20.32%), which were similar to those of vegetable oils. The methyl ester conversion via a transesterification process gave a yield between 85 and 90%. The biodiesel qualities were in reasonable agreement with both EN 14214 and ASTM D6751 standards. A preliminary financial analysis showed that the production cost of biodiesel from SBE oils was significantly lower than the pre-tax price of fossil diesel or those made of vegetable oils or waste cooking oils. The effects of the crude oil price and the investment on the production cost and the investment return period were also conducted. The result showed that the investment would return faster at higher crude oil price. (author)