Estimation of glomerular filtration rate in cancer patients with abnormal body composition and relation with carboplatin toxicity.

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Bretagne, M; Jouinot, A; Durand, J P; Huillard, O; Boudou Rouquette, P; Tlemsani, C; Arrondeau, J; Sarfati, G; Goldwasser, F; Alexandre, J

2017-07-01

Carboplatin clearance is correlated with glomerular filtration rate (GFR) and usually estimated with creatinine clearance using Cockcroft-Gault (CG) formula. Because plasma creatinine level is highly correlated with muscle mass, we hypothesized that an abnormal body composition with a low lean body mass (LBM) percentage [(LBM/weight) × 100] may result in inadequate carboplatin dosing. Serum cystatin C is an alternative marker of GFR, not affected by muscle mass. We aimed to investigate the influence of total LBM and LBM percentage on GFR calculation, using creatinine (CrCl) or cystatin C (GFR cysC-creat ) in cancer patients. Pretreatment serum creatinine and cystatin C were prospectively measured in consecutive patients. CrCl (CG formula), GFR cysC-creat (CKD-EPI creatinine-cystatin equation), and LBM (CT scan) were calculated. Severe thrombocytopenia post-carboplatin were analyzed. In 131 patients without renal insufficiency, LBM was correlated with creatinine (r = 0.30, p LBM percentage, the CrCl was significantly higher than GFR cysC-creat indicating an overestimation of GFR with creatinine (p = 0.0004). In 24 patients treated with carboplatin AUC 5 (mg/ml min) ± paclitaxel, the risk of severe thrombocytopenia was associated with lower LBM percentage (p = 0.0002) and higher CrCl/GFR cysC-creat ratio (p = 0.006). By ROC analysis, the CrCl/GFR cysC-creat ratio threshold predicting severe thrombocytopenia was 1.23. A low LBM percentage increases the risk of inadequate GFR calculation by CG formula, and carboplatin overdosage with severe thrombocytopenia. High CrCl/GFR cysC-creat ratio allows the identification of these patients.

Dexamethasone Modifies Cystatin C-Based Diagnosis of Acute Kidney Injury During Cisplatin-Based Chemotherapy

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Timothy J. Pianta

2017-03-01

Full Text Available Background/Aims: Plasma cystatin C (pCysC may be superior to serum creatinine (sCr as a surrogate of GFR. However, the performance of pCysC for diagnosing acute kidney injury (AKI after cisplatin-based chemotherapy is potentially affected by accompanying corticosteroid anti-emetic therapy and hydration. Methods: In a prospective observational study pCysC, sCr, urinary kidney injury molecule-1 (KIM-1, and urinary clusterin were measured over 2 weeks in 27 patients given first-cycle chemotherapy. The same variables were measured over 2 weeks in Sprague–Dawley rats given a single intraperitoneal injection of dexamethasone, cisplatin, or both, and in controls. Results: In patients, pCysC increases were greater than sCr 41% vs. 16%, mean paired difference 25% (95% CI: 16–34%], relative increases were ≥ 50% in 9 patients (35% for pCysC compared with 2 (8% for sCr (p = 0.04 and increases in sCr were accompanied by increased KIM-1 and clusterin excretion, but increases in pCysC alone were not. In rats, dexamethasone administration produced dose-dependent increases in pCysC (and augmented cisplatin-induced increases in pCysC, but did not augment histological injury, increases in sCr, or KIM-1 and clusterin excretion. Conclusions: In the presence of dexamethasone, elevation of pCysC does not reliably diagnose AKI after cisplatin-based chemotherapy.

Performance in Measurement of Serum Cystatin C by Laboratories Participating in the College of American Pathologists 2014 CYS Survey.

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Eckfeldt, John H; Karger, Amy B; Miller, W Greg; Rynders, Gregory P; Inker, Lesley A

2015-07-01

Cystatin C is becoming an increasingly popular biomarker for estimating glomerular filtration rate, and accurate measurements of cystatin C concentrations are necessary for accurate estimates of glomerular filtration rate. To assess the accuracy of cystatin C concentration measurements in laboratories participating in the College of American Pathologists CYS Survey. Two fresh frozen serum pools, the first from apparently healthy donors and the second from patients with chronic kidney disease, were prepared and distributed to laboratories participating in the CYS Survey along with the 2 usual processed human plasma samples. Target values were established for each pool by using 2 immunoassays and ERM DA471/IFCC international reference material. For the normal fresh frozen pool (ERM-DA471/IFCC-traceable target of 0.960 mg/L), the all-method mean (SD, % coefficient of variation [CV]) reported by all of the 123 reporting laboratories was 0.894 mg/L (0.128 mg/L, 14.3%). For the chronic kidney disease pool (ERM-DA471/IFCC-traceable target of 2.37 mg/L), the all-method mean (SD, %CV) was 2.258 mg/L (0.288 mg/L, 12.8%). There were substantial method-specific biases (mean milligram per liter reported for the normal pool was 0.780 for Siemens, 0.870 for Gentian, 0.967 for Roche, 1.061 for Diazyme, and 0.970 for other/not specified reagents; and mean milligram per liter reported for the chronic kidney disease pool was 2.052 for Siemens, 2.312 for Gentian, 2.247 for Roche, 2.909 for Diazyme, and 2.413 for other/not specified reagents). Manufacturers need to improve the accuracy of cystatin C measurement procedures if cystatin C is to achieve its full potential as a biomarker for estimating glomerular filtration rate.

β-Ga2O3:Cr(3+) nanoparticle: A new platform with near infrared photoluminescence for drug targeting delivery and bio-imaging simultaneously.

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Wang, Xin-Shi; Situ, Jun-Qing; Ying, Xiao-Ying; Chen, Hui; Pan, Hua-fei; Jin, Yi; Du, Yong-Zhong

2015-08-01

Multifunctional nanoparticles which integrate the therapeutic agents and bio-imaging agents into one carrier are emerging as a promising therapeutic platform. Herein, GaOOH:Cr(3+) was firstly synthesized using improved hydrothermal method (atmospheric pressure, 95 °C), and by manipulating the pH of the reaction medium, GaOOH:Cr(3+) with different sizes (125.70 nm, 200.60 nm and 313.90 nm) were synthesized. Then β-Ga2O3:Cr(3+) nanoparticles with porous structures were developed as a result of the calcination of GaOOH:Cr(3+). The fabricated, porous β-Ga2O3:Cr(3+) nanoparticles could effectively absorb doxorubicin hydrochloride (DOX) (loading rate: 8% approximately) and had near infrared photoluminescence with a 695 nm emission. Furthermore, β-Ga2O3:Cr(3+) nanoparticles were coated with l-Cys modified hyaluronic acid (HA-Cys) by exploiting the electrostatic interaction and the cross-link effect of disulfide bond to improve the stability. The DOX loaded HA-Cys coated β-Ga2O3:Cr(3+) nanoparticles (HA/β-Ga2O3:Cr(3+)/DOX) showed an oxidation-reduction sensitive drug release behavior. The HA-Cys coated β-Ga2O3:Cr(3+) nanoparticles showed a low cytotoxicity on MCF-7 and Hela cell lines. The cellular uptake of HA/β-Ga2O3:Cr(3+)/DOX using the near infrared photoluminescence of β-Ga2O3:Cr(3+) nanoparticles and the fluorescence of DOX demonstrated the HA/β-Ga2O3:Cr(3+)/DOX could internalize into tumor cells quickly, which was affected by the size and shape of β-Ga2O3:Cr(3+)nanoparticles. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Native chemical ligation at Asx-Cys, Glx-Cys: chemical synthesis and high-resolution X-ray structure of ShK toxin by racemic protein crystallography.

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Dang, Bobo; Kubota, Tomoya; Mandal, Kalyaneswar; Bezanilla, Francisco; Kent, Stephen B H

2013-08-14

We have re-examined the utility of native chemical ligation at -Gln/Glu-Cys- [Glx-Cys] and -Asn/Asp-Cys- [Asx-Cys] sites. Using the improved thioaryl catalyst 4-mercaptophenylacetic acid (MPAA), native chemical ligation could be performed at -Gln-Cys- and Asn-Cys- sites without side reactions. After optimization, ligation at a -Glu-Cys- site could also be used as a ligation site, with minimal levels of byproduct formation. However, -Asp-Cys- is not appropriate for use as a site for native chemical ligation because of formation of significant amounts of β-linked byproduct. The feasibility of native chemical ligation at -Gln-Cys- enabled a convergent total chemical synthesis of the enantiomeric forms of the ShK toxin protein molecule. The D-ShK protein molecule was ~50,000-fold less active in blocking the Kv1.3 channel than the L-ShK protein molecule. Racemic protein crystallography was used to obtain high-resolution X-ray diffraction data for ShK toxin. The structure was solved by direct methods and showed significant differences from the previously reported NMR structures in some regions of the ShK protein molecule.

On-resin conversion of Cys(Acm)-containing peptides to their corresponding Cys(Scm) congeners.

Science.gov (United States)

Mullen, Daniel G; Weigel, Benjamin; Barany, George; Distefano, Mark D

2010-05-01

The Acm protecting group for the thiol functionality of cysteine is removed under conditions (Hg(2+)) that are orthogonal to the acidic milieu used for global deprotection in Fmoc-based solid-phase peptide synthesis. This use of a toxic heavy metal for deprotection has limited the usefulness of Acm in peptide synthesis. The Acm group may be converted to the Scm derivative that can then be used as a reactive intermediate for unsymmetrical disulfide formation. It may also be removed by mild reductive conditions to generate unprotected cysteine. Conversion of Cys(Acm)-containing peptides to their corresponding Cys(Scm) derivatives in solution is often problematic because the sulfenyl chloride reagent used for this conversion may react with the sensitive amino acids tyrosine and tryptophan. In this protocol, we report a method for on-resin Acm to Scm conversion that allows the preparation of Cys(Scm)-containing peptides under conditions that do not modify other amino acids. (c) 2010 European Peptide Society and John Wiley & Sons, Ltd.

Identification and expression analysis of CYS-A1, CYS-C1, NIT4 genes in rice seedlings exposed to cyanide.

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Yu, Xiao-Zhang; Lin, Yu-Juan; Lu, Chun-Jiao; Zhang, Xue-Hong

2017-09-01

Involvement of genes (CYS-A1, CYS-C1 and NIT4) encoded with cysteine synthase, β-cyanoalanine synthase, nitrilase and cyanide metabolisms are evident in Arabidopsis. In the present study, identifications of CYS-A1, CYS-C1 and NIT4, predictions of conserved motifs, and constructions of phylogenetic relationships, based on their amino acid sequences in rice, were conducted. In order to elucidate the transcriptional responses of these cyanide-degrading genes, two candidate homologues were selected for each gene to test their expression changes upon exposure to exogenous KCN in rice seedlings using RT-PCR. Results showed that all selected candidate homologous genes were differentially expressed at different exposure points in roots and shoots of rice seedlings, suggesting their distinct roles during cyanide assimilation. Both candidate homologues for CYS-A1 constantly exhibited more abundant transcripts in comparison to control. However, only one candidate homologue for CYS-C1 and NIT4 showed a remarkable up-regulation during KCN exposure. Analysis of both tissue and solution cyanide indicated that rice seedlings were quickly able to metabolize exogenous KCN with minor accumulation in plant tissues. In conclusion, significant up-regulation of CYS-A1 suggested that the endogenous pool of cysteine catalyzed by cysteine synthase does not restrict the conversion of exogenous KCN into cyanoalanine through the β-cyanoalanine pathway. However, insufficient responses of the transcription level of NIT4 suggested that NIT enzyme may be a limiting factor for cyanoalanine assimilation by rice seedlings.

Cys34 Adductomes Differ between Patients with Chronic Lung or Heart Disease and Healthy Controls in Central London.

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Liu, Sa; Grigoryan, Hasmik; Edmands, William M B; Dagnino, Sonia; Sinharay, Rudy; Cullinan, Paul; Collins, Peter; Chung, Kian Fan; Barratt, Benjamin; Kelly, Frank J; Vineis, Paolo; Rappaport, Stephen M

2018-02-20

Oxidative stress generates reactive species that modify proteins, deplete antioxidant defenses, and contribute to chronic obstructive pulmonary disease (COPD) and ischemic heart disease (IHD). To determine whether protein modifications differ between COPD or IHD patients and healthy subjects, we performed untargeted analysis of adducts at the Cys34 locus of human serum albumin (HSA). Biospecimens were obtained from nonsmoking participants from London, U.K., including healthy subjects (n = 20) and patients with COPD (n = 20) or IHD (n = 10). Serum samples were digested with trypsin and analyzed by liquid chromatography-high resolution mass spectrometry. Effects of air pollution on adduct levels were also investigated based on estimated residential exposures to PM 2.5 , O 3 and NO 2 . For the 39 adducts with sufficient data, levels were essentially identical in blood samples collected from the same subjects on two consecutive days, consistent with the 28 day residence time of HSA. Multivariate linear regression revealed 21 significant associations, mainly with the underlying diseases but also with air-pollution exposures (p-value < 0.05). Interestingly, most of the associations indicated that adduct levels decreased with the presence of disease or increased pollutant concentrations. Negative associations of COPD and IHD with the Cys34 disulfide of glutathione and two Cys34 sulfoxidations, were consistent with previous results from smoking and nonsmoking volunteers and nonsmoking women exposed to indoor combustion of coal and wood.

The influence of the Cys46/Cys55 disulfide bond on the redox and spectroscopic properties of human neuroglobin.

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Bellei, Marzia; Bortolotti, Carlo Augusto; Di Rocco, Giulia; Borsari, Marco; Lancellotti, Lidia; Ranieri, Antonio; Sola, Marco; Battistuzzi, Gianantonio

2018-01-01

Neuroglobin is a monomeric globin containing a six-coordinate heme b, expressed in the nervous system, which exerts an important neuroprotective role. In the human protein (hNgb), Cys46 and Cys55 form an intramolecular disulfide bond under oxidizing conditions, whose cleavage induces a helix-to-strand rearrangement of the CD loop that strengthens the bond between the heme iron and the distal histidine. Hence, it is conceivable that the intramolecular disulfide bridge modulates the functionality of human neuroglobin by controlling exogenous ligand binding. In this work, we investigated the influence of the Cys46/Cys55 disulfide bond on the redox properties and on the pH-dependent conformational equilibria of hNgb, using UV-vis spectroelectrochemistry, cyclic voltammetry, electronic absorption spectroscopy and magnetic circular dichroism (MCD). We found that the SS bridge significantly affects the heme Fe(III) to Fe(II) reduction enthalpy (ΔH°' rc ) and entropy (ΔS°' rc ), mostly as a consequence of changes in the reduction-induced solvent reorganization effects, without affecting the axial ligand-binding interactions and the polarity and electrostatics of the heme environment. Between pH3 and 12, the electronic properties of the heme of ferric hNgb are sensitive to five acid-base equilibria, which are scarcely affected by the Cys46/Cys55 disulfide bridge. The equilibria occurring at extreme pH values induce heme release, while those occurring between pH5 and 10 alter the electronic properties of the heme without modifying its axial coordination and low spin state. They involve the sidechains of non-coordinating aminoacids close to the heme and at least one heme propionate. Copyright © 2017 Elsevier Inc. All rights reserved.

Serum cystatin C concentration measured routinely is a prognostic marker for renal disease in dogs.

Science.gov (United States)

Iwasa, Naoki; Takashima, Satoshi; Iwasa, Tatsuo; Iwasa, Kazuko; Suzuki, Tomomi; Kobatake, Yui; Kitagawa, Hitoshi; Nishii, Naohito

2018-06-14

This study examined the predictive value of serum cystatin C (Cys-C) concentration, measured during routine periodic health examinations, in the renal prognosis of dogs. A cohort of 140 dogs weighing C concentrations were measured during periodic health examinations from December 2013 to March 2016 were prospectively studied, with renal disease-related death the predicted end point. Of the 140 dogs, nine died from renal diseases during the follow-up period (539 ± 249 days). Serum Cys-C concentrations were higher in the dogs that subsequently died of renal disease than in the censored group (0.8 ± 0.25 vs. 0.3 ± 0.1 mg/dl, respectively; P C concentrations (>0.55 mg/dl) had a shorter (P C concentrations (≤0.55 mg/dl). In conclusion, high serum Cys-C concentrations in periodic health examinations in dogs <15 kg predicted poorer prognosis for renal function. Copyright © 2018. Published by Elsevier Ltd.

Serum Cistatin C in patients with delayed graft function

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Todor Gruev

2006-04-01

Full Text Available Despite recent studies showing that serum Cystatin C(CysC is a better marker for glomerular filtration rate (GFR than the ubiquitously used creatinine, the clinical utility of this remains to be evaluated. This marker is very sensitive for alograft function after renal transplantation. Concentration of CysC was compared with that of creatinine. Decreased renal function was followed in 64 transplanted patients. Plasma CysC significantly correlated (r=0.625, p<0.001 with creatinine in healthy controls. In these patients the mean plasma creatinine and Cystatin C concentrations were: 81+/-13 mmol/L,0.90 +/-0.22 mg/L, respectively. Plasma Cystatin C and creatinine significantly correlated throughout the post-transplantation period (r=0.686, p<0.001, but we confirmed differences between kinetics of these parameters. In the first four days after transplantation the CysC concentration was normalized faster than creatinine concentration. Development of acute rejection episode ( between 5 and 7 days showed high sensitivity and specificity of the changes of CysC compared with those of creatinine

Structure-based analysis of CysZ-mediated cellular uptake of sulfate

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Assur Sanghai, Zahra; Liu, Qun; Clarke, Oliver B; Belcher-Dufrisne, Meagan; Wiriyasermkul, Pattama; Giese, M Hunter; Leal-Pinto, Edgar; Kloss, Brian; Tabuso, Shantelle; Love, James; Punta, Marco; Banerjee, Surajit; Rajashankar, Kanagalaghatta R; Rost, Burkhard; Logothetis, Diomedes; Quick, Matthias; Hendrickson, Wayne A

2018-01-01

Sulfur, most abundantly found in the environment as sulfate (SO42-), is an essential element in metabolites required by all living cells, including amino acids, co-factors and vitamins. However, current understanding of the cellular delivery of SO42- at the molecular level is limited. CysZ has been described as a SO42- permease, but its sequence family is without known structural precedent. Based on crystallographic structure information, SO42- binding and flux experiments, we provide insight into the molecular mechanism of CysZ-mediated translocation of SO42- across membranes. CysZ structures from three different bacterial species display a hitherto unknown fold and have subunits organized with inverted transmembrane topology. CysZ from Pseudomonas denitrificans assembles as a trimer of antiparallel dimers and the CysZ structures from two other species recapitulate dimers from this assembly. Mutational studies highlight the functional relevance of conserved CysZ residues. PMID:29792261

Comparison of Glomerular Filtration Rate Estimation from Serum Creatinine and Cystatin C in HNF1A-MODY and Other Types of Diabetes.

Science.gov (United States)

Szopa, Magdalena; Kapusta, Maria; Matejko, Bartlomiej; Klupa, Tomasz; Koblik, Teresa; Kiec-Wilk, Beata; Borowiec, Maciej; Malecki, Maciej T

2015-01-01

We previously showed that in HNF1A-MODY the cystatin C-based glomerular filtration rate (GFR) estimate is higher than the creatinine-based estimate. Currently, we aimed to replicate this finding and verify its clinical significance. The study included 72 patients with HNF1A-MODY, 72 with GCK-MODY, 53 with type 1 diabetes (T1DM), 70 with type 2 diabetes (T2DM), and 65 controls. Serum creatinine and cystatin C levels were measured. GFR was calculated from creatinine and cystatin C using the CKD-EPI creatinine equation (eGRF-cr) and CKD-EPI cystatin C equation (eGFR-cys), respectively. Cystatin C levels were lower (p MODY, GCK-MODY, and the controls (p = 0.004; p = 0.003; p MODY patients are higher compared to eGFR-cr. Some other differences were also described in diabetic groups. However, none of them appears to be clinically relevant.

The Comparative Study of the Measurement of Serum Cystatin C and 99mTc-DTPA for the Measurement of Glomerular Filtration Rate (GFR) in Type 2 Diabetic Nephropathy

International Nuclear Information System (INIS)

Kong Linghua; Wu Junyuan; Gao Bin; Wang Xueqin; Gu Kaikai

2010-01-01

To explore the clinical value between measurement of serum cystatin C (Cys C) and determination of plasma with 99m Tc-DTPA glomerular filtration rate (GFR) clearance for type 2 diabetes (T2DM) in early detection of renal damage, the serum cystatin C levels in 87 patients with type 2 diabetes were determined by immune turbidimetry Cys C. The patients were also carried out dynamic imaging to measure renal GFR. The result showed that the serum levels of Cys C in patients with Type 2 diabetic was 1.68 ± 0.52 mg / L, the normal group was 0.72±0.26 mg/L; The GFR in patients with T2DM was 93.8 ± 30.2 ml/min/1.73m 2 , the control group was 107.48±15.23 ml/min/1.73m 2 , there was significant difference between patients and controls (P 99m Tc-DTPA renal dynamic imaging. The serum Cys C could reflect the damage in early diabetic patients. The method is simple, accurate and easy to spread. The renal dynamic imaging method of GFR determination is slightly complex and requires specialized equipment. It can reflect the sub-renal function. The combined measurement of serum Cys C and GFR are very important in the early detection of type 2 diabetic patients with early renal function. (authors)

Bovine Serum Albumin binding to CoCrMo nanoparticles and the influence on dissolution

International Nuclear Information System (INIS)

Simoes, T A; Brown, A P; Milne, S J; Brydson, R M D

2015-01-01

CoCrMo alloys exhibit good mechanical properties, excellent biocompatibility and are widely utilised in orthopaedic joint replacements. Metal-on-metal hip implant degradation leads to the release of metal ions and nanoparticles, which persist through the implant's life and could be a possible cause of health complications. This study correlates preferential binding between proteins and metal alloy nanoparticles to the alloy's corrosion behaviour and the release of metal ions. TEM images show the formation of a protein corona in all particles immersed in albumin containing solutions. Only molybdenum release was significant in these tests, suggesting high dissolution of this element when CoCrMo alloy nanoparticles are produced as wear debris in the presence of serum albumin. The same trend was observed during extended exposure of molybdenum reference nanoparticles to albumin. (paper)

Characterization of the Arabidopsis thaliana 2-Cys peroxiredoxin interactome.

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Cerveau, Delphine; Kraut, Alexandra; Stotz, Henrik U; Mueller, Martin J; Couté, Yohann; Rey, Pascal

2016-11-01

Peroxiredoxins are ubiquitous thiol-dependent peroxidases for which chaperone and signaling roles have been reported in various types of organisms in recent years. In plants, the peroxidase function of the two typical plastidial 2-Cys peroxiredoxins (2-Cys PRX A and B) has been highlighted while the other functions, particularly in ROS-dependent signaling pathways, are still elusive notably due to the lack of knowledge of interacting partners. Using an ex vivo approach based on co-immunoprecipitation of leaf extracts from Arabidopsis thaliana wild-type and mutant plants lacking 2-Cys PRX expression followed by mass spectrometry-based proteomics, 158 proteins were found associated with 2-Cys PRXs. Already known partners like thioredoxin-related electron donors (Chloroplastic Drought-induced Stress Protein of 32kDa, Atypical Cysteine Histidine-rich Thioredoxin 2) and enzymes involved in chlorophyll synthesis (Protochlorophyllide OxidoReductase B) or carbon metabolism (Fructose-1,6-BisPhosphatase) were identified, validating the relevance of the approach. Bioinformatic and bibliographic analyses allowed the functional classification of the identified proteins and revealed that more than 40% are localized in plastids. The possible roles of plant 2-Cys PRXs in redox signaling pathways are discussed in relation with the functions of the potential partners notably those involved in redox homeostasis, carbon and amino acid metabolisms as well as chlorophyll biosynthesis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Transcriptional regulation of Saccharomyces cerevisiaeCYS3 encoding cystathionine γ-lyase

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Hiraishi, Hiroyuki; Miyake, Tsuyoshi

2008-01-01

In studying the regulation of GSH11, the structural gene of the high-affinity glutathione transporter (GSH-P1) in Saccharomyces cerevisiae, a cis-acting cysteine responsive element, CCGCCACAC (CCG motif), was detected. Like GSH-P1, the cystathionine γ-lyase encoded by CYS3 is induced by sulfur starvation and repressed by addition of cysteine to the growth medium. We detected a CCG motif (−311 to −303) and a CGC motif (CGCCACAC; −193 to −186), which is one base shorter than the CCG motif, in the 5′-upstream region of CYS3. One copy of the centromere determining element 1, CDE1 (TCACGTGA; −217 to −210), being responsible for regulation of the sulfate assimilation pathway genes, was also detected. We tested the roles of these three elements in the regulation of CYS3. Using a lacZ-reporter assay system, we found that the CCG/CGC motif is required for activation of CYS3, as well as for its repression by cysteine. In contrast, the CDE1 motif was responsible for only activation of CYS3. We also found that two transcription factors, Met4 and VDE, are responsible for activation of CYS3 through the CCG/CGC and CDE1 motifs. These observations suggest a dual regulation of CYS3 by factors that interact with the CDE1 motif and the CCG/CGC motifs. PMID:18317767

The cys regulon of Xanthomonas citri

International Nuclear Information System (INIS)

Moutran, A.; Balan, A.

2012-01-01

Full text: In Escherichia coli, genes involved in metabolic pathway of sulfate and sulfonate compounds are clustered in a cys regulon, which includes three ABC transport system (operons: sbpcysWUA; ssuABC and tauABC), thirteen genes involved in the sulfur reduction (ssuDE; tauD and cysDNCHIJGK) and two regulatory proteins that belong to LysR transcription family: CysB and Cbl. Notably, a search and comparative analysis of these genes in the genomes of the citrus pathogen Xanthomonas citri and other phylogenetically related Xanthomonas species revealed the presence of genes involved with alkanesulfonate, sulfate ester and taurine, only in X. citri, suggesting that proteins from this regulon might be associated with pathogenicity in citrus. Using the molecular modeling associated with a system biology view, we modeled all the protein structures of the X. citri cys regulon as well as characterized the important residues forming the putative active sites. Comparison with orthologs from different microorganisms was made in order to get a phylogenetic relationships. We showed that proteins that are responsible for the affinity and specificity of the alkanesulfonate, sulfate and taurine transport systems conserved the residues involved in the sulfate coordination but are organized in different branches in evolution. Inside these phylogenetic branches, proteins involved in the sulfate transporter are highly conserved when compared to the others. Moreover, we identified that the taurine-binding protein (TauA) of the X. citri belongs to a different evolutionary branch from that one that described for E. coli. These differences were also noticed for components of the tau operon, including a putative new regulator. The function and mechanism of action of each protein is discussed in order to bring light for the sulfur assimilation processes and their importance for X. citri physiology. (author)

The cys regulon of Xanthomonas citri

Energy Technology Data Exchange (ETDEWEB)

Moutran, A.; Balan, A. [Laboratorio Nacional de Biociencias - LNBIO, Campinas, SP (Brazil)

2012-07-01

Full text: In Escherichia coli, genes involved in metabolic pathway of sulfate and sulfonate compounds are clustered in a cys regulon, which includes three ABC transport system (operons: sbpcysWUA; ssuABC and tauABC), thirteen genes involved in the sulfur reduction (ssuDE; tauD and cysDNCHIJGK) and two regulatory proteins that belong to LysR transcription family: CysB and Cbl. Notably, a search and comparative analysis of these genes in the genomes of the citrus pathogen Xanthomonas citri and other phylogenetically related Xanthomonas species revealed the presence of genes involved with alkanesulfonate, sulfate ester and taurine, only in X. citri, suggesting that proteins from this regulon might be associated with pathogenicity in citrus. Using the molecular modeling associated with a system biology view, we modeled all the protein structures of the X. citri cys regulon as well as characterized the important residues forming the putative active sites. Comparison with orthologs from different microorganisms was made in order to get a phylogenetic relationships. We showed that proteins that are responsible for the affinity and specificity of the alkanesulfonate, sulfate and taurine transport systems conserved the residues involved in the sulfate coordination but are organized in different branches in evolution. Inside these phylogenetic branches, proteins involved in the sulfate transporter are highly conserved when compared to the others. Moreover, we identified that the taurine-binding protein (TauA) of the X. citri belongs to a different evolutionary branch from that one that described for E. coli. These differences were also noticed for components of the tau operon, including a putative new regulator. The function and mechanism of action of each protein is discussed in order to bring light for the sulfur assimilation processes and their importance for X. citri physiology. (author)

Quantitative analyses of schizophrenia-associated metabolites in serum: serum D-lactate levels are negatively correlated with gamma-glutamylcysteine in medicated schizophrenia patients.

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Takeshi Fukushima

Full Text Available The serum levels of several metabolites are significantly altered in schizophrenia patients. In this study, we performed a targeted analysis of 34 candidate metabolites in schizophrenia patients (n = 25 and compared them with those in age- and gender-matched healthy subjects (n = 27. Orthogonal partial least square-discriminant analysis revealed that complete separation between controls and patients was achieved based on these metabolites. We found that the levels of γ-glutamylcysteine (γ-GluCys, linoleic acid, arachidonic acid, D-serine, 3-hydroxybutyrate, glutathione (GSH, 5-hydroxytryptamine, threonine, and tyrosine were significantly lower, while D-lactate, tryptophan, kynurenine, and glutamate levels were significantly higher in schizophrenia patients compared to controls. Using receiver operating characteristics (ROC curve analysis, the sensitivity, specificity, and the area under curve of γ-GluCys, a precursor of GSH, and D-lactate, a terminal metabolite of methylglyoxal, were 88.00%, 81.48%, and 0.8874, and 88.00%, 77.78%, and 0.8415, respectively. In addition, serum levels of D-lactate were negatively correlated with γ-GluCys levels in patients, but not in controls. The present results suggest that oxidative stress-induced damage may be involved in the pathogenesis of schizophrenia.

Efficient reduction of Cys110 thiyl radical by glutathione in human myoglobin

OpenAIRE

Nagao, Satoshi; Asami, Osamu; Yasui, Hiroyuki; Hirota, Shun

2011-01-01

Human myoglobin (hMb) possesses a cysteine (Cys) residue which is rare among mammalian Mbs. To investigate the effects of this unique Cys residue at the amino acid position 110 (Cys110) on hMb reactions, we studied the reactions of wild type (WT) methMb and its alanine mutant at Cys110 (C110A) with H2O2, particularly in the presence of reduced glutathione (GSH) which is well known as a reducing agent. The formation rates of the ferryloxo (Fe(IV) = O) species by H2O2 under air were about the s...

Principles of agonist recognition in Cys-loop receptors

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Timothy eLynagh

2014-04-01

Full Text Available Cys-loop receptors are ligand-gated ion channels that are activated by a structurally diverse array of neurotransmitters, including acetylcholine, serotonin, glycine and GABA. After the term chemoreceptor emerged over 100 years ago, there was some wait until affinity labeling, molecular cloning, functional studies and X-ray crystallography experiments identified the extracellular interface of adjacent subunits as the principal site of agonist binding. The question of how subtle differences at and around agonist-binding sites of different Cys-loop receptors can accommodate transmitters as chemically diverse as glycine and serotonin has been subject to intense research over the last three decades. This review outlines the functional diversity and current structural understanding of agonist-binding sites, including those of invertebrate Cys-loop receptors. Together, this provides a framework to understand the atomic determinants involved in how these valuable therapeutic targets recognize and bind their ligands.

Reference intervals for serum cystatin C and creatinine of an ...

African Journals Online (AJOL)

2014-09-25

Sep 25, 2014 ... Some studies suggest that GFR estimated from serum cystatin C (Cys C) is more accurate than ... Current clinical practice guidelines[1,2] recommend the use of ..... Source of Support: Nil, Conflict of Interest: None declared.

Physiological relevance of plant 2-Cys peroxiredoxin overoxidation level and oligomerization status.

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Cerveau, Delphine; Ouahrani, Djelloul; Marok, Mohamed Amine; Blanchard, Laurence; Rey, Pascal

2016-01-01

Peroxiredoxins are ubiquitous thioredoxin-dependent peroxidases presumed to display, upon environmental constraints, a chaperone function resulting from a redox-dependent conformational switch. In this work, using biochemical and genetic approaches, we aimed to unravel the factors regulating the redox status and the conformation of the plastidial 2-Cys peroxiredoxin (2-Cys PRX) in plants. In Arabidopsis, we show that in optimal growth conditions, the overoxidation level mainly depends on the availability of thioredoxin-related electron donors, but not on sulfiredoxin, the enzyme reducing the 2-Cys PRX overoxidized form. We also observed that upon various physiological temperature, osmotic and light stress conditions, the overoxidation level and oligomerization status of 2-Cys PRX can moderately vary depending on the constraint type. Further, no major change was noticed regarding protein conformation in water-stressed Arabidopsis, barley and potato plants, whereas species-dependent up- and down-variations in overoxidation were observed. In contrast, both 2-Cys PRX overoxidation and oligomerization were strongly induced during a severe oxidative stress generated by methyl viologen. From these data, revealing that the oligomerization status of plant 2-Cys PRX does not exhibit important variation and is not tightly linked to the protein redox status upon physiologically relevant environmental constraints, the possible in planta functions of 2-Cys PRX are discussed. © 2015 John Wiley & Sons Ltd.

The CrIIL reduction of [2Fe-2S] ferredoxins and site of attachment of CrIII using 1H NMR and site-directed mutagenesis.

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Im, S C; Worrall, J A; Liu, G; Aliverti, A; Zanetti, G; Luchinat, C; Bertini, I; Sykes, A G

2000-04-17

The recently reported NMR solution structure of FeIIIFeIII parsley FdI has made possible 2D NOESY NMR studies to determine the point of attachment of CrIIIL in FeIIIFeIII...CrIIIL. The latter Cr-modified product was obtained by reduction of FeIIIFeIII parsley and spinach FdI forms with [Cr(15-aneN4) (H2O)2]2+ (15-aneN4 = 1,4,8,12-tetraazacyclopentadecane), referred to here as CrIIL, followed by air oxidation and chromatographic purification. From a comparison of NMR cross-peak intensities of native and Cr-modified proteins, two surface sites designated A and B, giving large paramagnetic CrIIIL broadening of a number of amino acid peaks, have been identified. The effects at site A (residues 19-22, 27, and 30) are greater than those at site B (residues 92-94 and 96), which is on the opposite side of the protein. From metal (ICP-AES) and electrospray ionization mass spectrometry (EIMS) analyses on the Cr-modified protein, attachment of a single CrIIIL only is confirmed for both parsley and spinach FdI and FdII proteins. Electrostatic interaction of the 3+ CrIIIL center covalently attached to one protein molecule (charge approximately -18) with a second (like) molecule provides an explanation for the involvement of two regions. Thus for 3-4 mM FeIIIFeIII...CrIIIL solutions used in NMR studies (CrIIIL attached at A), broadening effects due to electrostatic interactions at B on a second molecule are observed. Experiments with the Cys18Ala spinach FdI variant have confirmed that the previously suggested Cys-18 at site A is not the site of CrIIIL attachment. Line broadening at Val-22 of A gives the largest effect, and CrIIIL attachment at one or more adjacent (conserved) acidic residues in this region is indicated. The ability of CrIIL to bind in some (parsley and spinach) but not all cases (Anabaena variabilis) suggests that intramolecular H-bonding of acidic residues at A is relevant. The parsley and spinach FeIIFeIII...CrIIIL products undergo a second stage of reduction

Effects of the Usage of l-Cysteine (l-Cys on Human Health

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Noelia Clemente Plaza

2018-03-01

Full Text Available This review summarizes recent knowledge about the use of the amino acid l-Cysteine (l-Cys through diet, nutritional supplements or drugs with the aim to improve human health or treat certain diseases. Three databases (PubMed, Scopus, and Web of Science and different keywords have been used to create a database of documents published between 1950 and 2017 in scientific journals in English or Spanish. A total of 60,885 primary publications were ultimately selected to compile accurate information about the use of l-Cys in medicine and nutritional therapies and to identify the reported benefits of l-Cys on human health. The number of publications about the use of l-Cys for these purposes has increased significantly during the last two decades. This increase seems to be closely related to the rise of nutraceutical industries and personalized medicine. The main evidence reporting benefits of l-Cys usage is summarized. However, the lack of accurate information and studies based on clinical trials hampers consensus among authors. Thus, the debate about the role and effectiveness of supplements/drugs containing l-Cys is still open.

Effects of the Usage of l-Cysteine (l-Cys) on Human Health.

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Clemente Plaza, Noelia; Reig García-Galbis, Manuel; Martínez-Espinosa, Rosa María

2018-03-03

This review summarizes recent knowledge about the use of the amino acid l-Cysteine (l-Cys) through diet, nutritional supplements or drugs with the aim to improve human health or treat certain diseases. Three databases (PubMed, Scopus, and Web of Science) and different keywords have been used to create a database of documents published between 1950 and 2017 in scientific journals in English or Spanish. A total of 60,885 primary publications were ultimately selected to compile accurate information about the use of l-Cys in medicine and nutritional therapies and to identify the reported benefits of l-Cys on human health. The number of publications about the use of l-Cys for these purposes has increased significantly during the last two decades. This increase seems to be closely related to the rise of nutraceutical industries and personalized medicine. The main evidence reporting benefits of l-Cys usage is summarized. However, the lack of accurate information and studies based on clinical trials hampers consensus among authors. Thus, the debate about the role and effectiveness of supplements/drugs containing l-Cys is still open.

Association of the hOGG1 Ser326Cys polymorphism with sporadic amyotrophic lateral sclerosis.

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Coppedè, Fabio; Mancuso, Michelangelo; Lo Gerfo, Annalisa; Carlesi, Cecilia; Piazza, Selina; Rocchi, Anna; Petrozzi, Lucia; Nesti, Claudia; Micheli, Dario; Bacci, Andrea; Migliore, Lucia; Murri, Luigi; Siciliano, Gabriele

2007-06-13

Amyotropic lateral sclerosis (ALS) is a fatal and progressive neurodegenerative disease causing the loss of motoneurons of the brain and the spinal cord. The etiology of ALS is still uncertain, but males are at increased risk for the disease than females. Several studies have suggested that motoneurons in ALS might be subjected to the double insult of increased DNA oxidative damage and deficiencies in DNA repair systems. Particularly, increased levels of 8-oxoguanine and impairments of the DNA base excision repair system have been observed in neurons of ALS patients. There is evidence that the Ser326Cys polymorphism of the human 8-oxoguanine DNA glycosylase 1 (hOGG1) gene is associated with a reduced DNA repair activity. To evaluate the role of the hOGG1 Ser326Cys polymorphism in sporadic ALS (sALS), we screened 136 patients and 129 matched controls. In the total population, we observed association between both the Cys326 allele (p=0.02) and the combined Ser326Cys+Cys326Cys genotype (OR=1.65, 95% CI=1.06-2.88) and increased risk of disease. After stratification by gender, the Cys326 allele (p=0.01), both the Ser326Cys genotype (OR=2.14, 95% CI=1.09-4.19) and the combined Ser326Cys+Cys326Cys genotype (OR=2.15, 95% CI=1.16-4.01) were associated with sALS risk only in males. No significant association between the Ser326Cys polymorphism and disease phenotype, including age and site of onset and disease progression, was observed. Present results suggest a possible involvement of the hOGG1 Ser326Cys polymorphism in sALS pathogenesis.

Catalytic mechanism of Sep-tRNA:Cys-tRNA synthase: sulfur transfer is mediated by disulfide and persulfide.

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Liu, Yuchen; Dos Santos, Patricia C; Zhu, Xiang; Orlando, Ron; Dean, Dennis R; Söll, Dieter; Yuan, Jing

2012-02-17

Sep-tRNA:Cys-tRNA synthase (SepCysS) catalyzes the sulfhydrylation of tRNA-bound O-phosphoserine (Sep) to form cysteinyl-tRNA(Cys) (Cys-tRNA(Cys)) in methanogens that lack the canonical cysteinyl-tRNA synthetase (CysRS). A crystal structure of the Archaeoglobus fulgidus SepCysS apoenzyme provides information on the binding of the pyridoxal phosphate cofactor as well as on amino acid residues that may be involved in substrate binding. However, the mechanism of sulfur transfer to form cysteine was not known. Using an in vivo Escherichia coli complementation assay, we showed that all three highly conserved Cys residues in SepCysS (Cys(64), Cys(67), and Cys(272) in the Methanocaldococcus jannaschii enzyme) are essential for the sulfhydrylation reaction in vivo. Biochemical and mass spectrometric analysis demonstrated that Cys(64) and Cys(67) form a disulfide linkage and carry a sulfane sulfur in a portion of the enzyme. These results suggest that a persulfide group (containing a sulfane sulfur) is the proximal sulfur donor for cysteine biosynthesis. The presence of Cys(272) increased the amount of sulfane sulfur in SepCysS by 3-fold, suggesting that this Cys residue facilitates the generation of the persulfide group. Based upon these findings, we propose for SepCysS a sulfur relay mechanism that recruits both disulfide and persulfide intermediates.

The Arabidopsis Phytocystatin AtCYS5 Enhances Seed Germination and Seedling Growth under Heat Stress Conditions.

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Song, Chieun; Kim, Taeyoon; Chung, Woo Sik; Lim, Chae Oh

2017-08-01

Phytocystatins (PhyCYSs) are plant-specific proteinaceous inhibitors that are implicated in protein turnover and stress responses. Here, we characterized a PhyCYS from Arabidopsis thaliana , which was designated AtCYS5. RT-qPCR analysis showed that the expression of AtCYS5 in germinating seeds was induced by heat stress (HS) and exogenous abscisic acid (ABA) treatment. Analysis of the expression of the β -glucuronidase reporter gene under the control of the AtCYS5 promoter showed that AtCYS5 expression during seed germination was induced by HS and ABA. Constitutive overexpression of AtCYS5 driven by the cauliflower mosaic virus 35S promoter led to enhanced HS tolerance in transgenic Arabidopsis , which was characterized by higher fresh weight and root length compared to wild-type (WT) and knockout ( cys5 ) plants grown under HS conditions. The HS tolerance of At-CYS5 -overexpressing transgenic plants was associated with increased insensitivity to exogenous ABA during both seed germination and post-germination compared to WT and cys5 . Although no HS elements were identified in the 5'-flanking region of AtCYS5 , canonical ABA-responsive elements (ABREs) were detected. AtCYS5 was upregulated in ABA-treated protoplasts transiently co-expressing this gene and genes encoding bZIP ABRE-binding factors (ABFs and AREB3). In the absence of ABA, ABF1 and ABF3 directly bound to the ABREs in the AtCYS5 promoter, which activated the transcription of this gene in the presence of ABA. These results suggest that an ABA-dependent pathway plays a positive role in the HS-responsive expression of AtCYS5 during seed germination and post-germination growth.

Serum Cystatin C Predicts AKI and the Prognosis of Patients in Coronary Care Unit: a Prospective, Observational Study

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Yugang Hu

2017-11-01

Full Text Available Background/Aims: Acute Kidney Injury (AKI is a serious clinical state associated with high morbidity and mortality, particularly in critical ill patients. We investigated the hypothesis that serum Cystatin C (sCysC is a good predictor for AKI and may affect the short-term prognosis of coronary care unit (CCU patients. Methods: In this prospective, observational study, we screened 412 adults admitted to the CCU from January 1, 2014 to June 1, 2015 at Zhongnan Hospital of Wuhan University. Serum samples were obtained at the time of admission, and sCysC was quantified through nephelometry. AKI was defined based on KDIGO-AKI criteria. After the patients’ hospital discharge, the survivors in this study were followed up for up to 2 years. The primary endpoint was the incidence of AKI stratified by severity stage, while the second endpoints included 2-year mortality, rehospitalization and failure in renal recovery rates, as well as the progression of AKI to CKD. Results: According to the KDIGO-AKI criteria, AKI occurred in 130 (31.6% patients. After multivariate adjustments, the highest quartile of sCysC was associated with a 9-fold increased risk of incident AKI compared with the lowest quartile. For predicting AKI, sCysC [area under the receiver operating characteristic curve (AUC=0.842] outperformed β2-micro globulin (AUC=0.813 and the clinical model (AUC=0.777, and a cutoff of 1.255 mg/L yielded good sensitivity and specificity. After a median 19.8-month follow-up, 112 (27.2% patients died within 2 years after admission. The sCysC independently predicted the risk of 2-year mortality [adjusted odds ratio (OR, 4.955; 95% confidence interval (95% CI, 2.853 to 8.603] and rehospitalization (OR, 3.128; 95% CI, 2.011 to 4.867, as well as renal recovery failure (OR, 3.618, 95% CI, 1.753 to 7.463. Conclusions: Serum CysC is a strong predictor of AKI and the short-term prognosis of CCU patients.

Influence of the OGG1 Ser326Cys polymorphism on oxidatively damaged DNA and repair activity

DEFF Research Database (Denmark)

Jensen, Annie Aarup; Løhr, Mille; Eriksen, Louise

2012-01-01

of the comet assay. We collected blood samples from 1,019 healthy subjects and genotyped for the OGG1 Ser326Cys polymorphism. We found 49 subjects homozygous for the variant genotype (Cys/Cys) and selected same numbers of age-matched subjects with the heterozygous (Ser/Cys) and homozygous wild-type genotype...

Preparation of 177Lu-DOTA/DTPA-Bz-Cys-RGD dimer and biodistribution evaluation in normal mice

International Nuclear Information System (INIS)

Sheng Feng; Jia Bing; Wang Fan; He Weiwei; Liu Zhaofei; Zhao Huiyun

2008-01-01

177 Lu-DOTA-Bz-Cys-RGD dimer and 177 Lu-DTPA-Bz-Cys-RGD dimer were prepared, and the in vitro and in vivo properties were compared. TLC and HPLC show that the labeling yields of two radiolabeled compounds are more than 95% under optimal conditions (pH=5.0, reacting at 100 degree C for 15-20 min), and the two radiolabeled compounds show pretty good in vitro stability. HPLC analyses and lg P values reveal that lipophilicity of 177 Lu-DOTA-Bz-Cys- RGD dimer is higher than 177 Lu-DTPA-Bz-Cys-RGD dimer. The uptake of 177 Lu-DTPA-Bz-Cys- RGD dimer in other tissues is significantly higher than that of 177 Lu-DOTA-Bz-Cys-RGD dimer at 4 h postinjection, except for blood and spleen. The in vivo stability of 177 Lu-DOTA-Bz-Cys-RGD dimer is much better than 177 Lu-DTPA-Bz-Cys-RGD dimer. Bz-DOTA is an ideal bifunctional chelator for 177 Lu labeling of RGD dimer. (authors)

Mutational analysis of Sep-tRNA:Cys-tRNA synthase reveals critical residues for tRNA-dependent cysteine formation.

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Helgadóttir, Sunna; Sinapah, Sylvie; Söll, Dieter; Ling, Jiqiang

2012-01-02

In methanogenic archaea, Sep-tRNA:Cys-tRNA synthase (SepCysS) converts Sep-tRNA(Cys) to Cys-tRNA(Cys). The mechanism of tRNA-dependent cysteine formation remains unclear due to the lack of functional studies. In this work, we mutated 19 conserved residues in Methanocaldococcus jannaschii SepCysS, and employed an in vivo system to determine the activity of the resulting variants. Our results show that three active-site cysteines (Cys39, Cys42 and Cys247) are essential for SepCysS activity. In addition, combined with structural modeling, our mutational and functional analyses also reveal multiple residues that are important for the binding of PLP, Sep and tRNA. Our work thus represents the first systematic functional analysis of conserved residues in archaeal SepCysSs, providing insights into the catalytic and substrate binding mechanisms of this poorly characterized enzyme. Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

The role of short-range Cys171-Cys178 disulfide bond in maintaining cutinase active site integrity: A molecular dynamics simulation

International Nuclear Information System (INIS)

Matak, Mehdi Youssefi; Moghaddam, Majid Erfani

2009-01-01

Understanding structural determinants in enzyme active site integrity can provide a good knowledge to design efficient novel catalytic machineries. Fusarium solani pisi cutinase with classic triad Ser-His-Asp is a promising enzyme to scrutinize these structural determinants. We performed two MD simulations: one, with the native structure, and the other with the broken Cys171-Cys178 disulfide bond. This disulfide bond stabilizes a turn in active site on which catalytic Asp175 is located. Functionally important H-bonds and atomic fluctuations in catalytic pocket have been changed. We proposed that this disulfide bond within active site can be considered as an important determinant of cutinase active site structural integrity.

Serum Cystatin C Concentrations in Cats with Hyperthyroidism and Chronic Kidney Disease.

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Williams, T L; Dillon, H; Elliott, J; Syme, H M; Archer, J

2016-07-01

Currently, no test can accurately predict the development of azotemia after treatment of hyperthyroidism. Serum cystatin C concentrations (sCysC) might be less influenced by changes in body muscle mass and so better indicate the presence of concurrent chronic kidney disease (CKD) in hyperthyroidism. sCysC will be higher in hyperthyroid cats that develop azotemia compared with hyperthyroid cats that remain nonazotemic after treatment; sCysC will be higher in nonhyperthyroid cats with azotemic CKD than healthy older cats and, sCysC will decrease after treatment of hyperthyroidism. Ninety-one cats treated in first opinion practice. Case-control study. sCysC were compared between hyperthyroid cats which developed azotemia within 4 months of successful treatment of hyperthyroidism (pre-azotemic group) and hyperthyroid cats which remained nonazotemic after treatment (nonazotemic group), and between nonhyperthyroid cats with azotemic CKD and healthy older cats. sCysC were also compared between hyperthyroid cats before treatment and at time of establishment of euthyroidism. Data are presented as median [25th, 75th percentile]. Baseline sCysC were not different between the pre-azotemic and nonazotemic groups (1.9 [1.4, 2.3] mg/L versus 1.5 [1.1, 2.2] mg/L, respectively; P = .22). sCysC in nonhyperthyroid cats with azotemic CKD and healthy older cats were not significantly different (1.5 [1.0, 1.9] mg/L versus 1.2 [0.8, 1.4] mg/L, respectively; P = .16). sCysC did not change significantly after treatment of hyperthyroidism (pretreatment 1.8 [1.2, 2.3] mg/L, after treatment 1.6 [1.1, 2.4] mg/L; P = .82). sCysC do not appear to be a reliable marker of renal function in hyperthyroid cats. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

CysLT(1)R antagonists inhibit tumor growth in a xenograft model of colon cancer.

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Savari, Sayeh; Liu, Minghui; Zhang, Yuan; Sime, Wondossen; Sjölander, Anita

2013-01-01

The expression of the inflammatory G-protein coupled receptor CysLT1R has been shown to be upregulated in colon cancer patients and associated with poor prognosis. The present study investigated the correlation between CysLT1R and colon cancer development in vivo using CysLT1R antagonists (ZM198,615 or Montelukast) and the nude mouse xenograft model. Two drug administration regimens were established. The first regimen was established to investigate the importance of CysLT1R in tumor initiation. Nude mice were inoculated with 50 µM CysLT1R antagonist-pretreated HCT-116 colon cancer cells and received continued treatment (5 mg/kg/day, intraperitoneally). The second regimen aimed to address the role of CysLT1R in tumor progression. Nude mice were inoculated with non-pretreated HCT-116 cells and did not receive CysLT1R antagonist treatment until recordable tumor appearance. Both regimens resulted in significantly reduced tumor size, attributed to changes in proliferation and apoptosis as determined by reduced Ki-67 levels and increased levels of p21(WAF/Cip1) (Pcolon cancer cell line HCT-116 and CysLT1R antagonists. In addition to significant reductions in cell proliferation, adhesion and colony formation, we observed induction of cell cycle arrest and apoptosis in a dose-dependent manner. The ability of Montelukast to inhibit growth of human colon cancer xenograft was further validated by using two additional colon cancer cell lines, SW-480 and HT-29. Our results demonstrate that CysLT1R antagonists inhibit growth of colon cancer xenografts primarily by reducing proliferation and inducing apoptosis of the tumor cells.

The Influence of Thyroid Function, Inflammation, and Obesity on Risk Prediction of Acute Kidney Injury by Cystatin C in the Emergency Department

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Moritz Schanz

2016-09-01

Full Text Available Background/Aims: There is a growing role for emergency departments (ED in assessing acute kidney injury (AKI for hospital admissions but there are few studies addressing acute kidney injury biomarkers and confounding factors in the ED. Cystatin C (CysC, a newer renal biomarker, is influenced by thyroid function, inflammation and obesity. This study aims to be the first study to address the impact of these parameters in the ED. Methods: Admitted patients (n=397 were enrolled in the ED at Robert-Bosch-Hospital, Stuttgart, Germany. Daily serum creatinine (sCr was recorded for AKI classification by Kidney Diseases Improves Global Outcome (KDIGO criteria. CysC, thyroid stimulating hormone (TSH, thyroxine (T4, C-reactive protein (CRP and body mass index (BMI were registered at enrollment in the ED. Serum samples were collected at enrollment, after 6 hours and in the following mornings (day 1 to day 3. The correlation of CysC and sCr was studied on a two variable logistic regression model. A linear predictor was computed to predict minimal AKI stage and area under the curve (AUC was calculated. Results: Of 397 patients enrolled for classification by KDIGO AKI criteria, n=152 (38% developed AKI, n=69 (17.4% reached AKI stage I, n=70 (17.6% AKI stage II, and n=13 (3% AKI stage III. Although a correlation between CRP and CysC levels was shown (rho=0.376, this didn't affect the predictive ability for AKI according to our data. We compared receiver operating characteristic (ROC curves (DeLong test of CysC to ROC curves of CysC with the additional variables TSH, BMI, and CRP respectively. Our data shows that addition of CRP, TSH, or BMI does not improve prediction of AKI stage beyond prediction based solely on CysC levels. Conclusions: CysC is known to be influenced by thyroid function, inflammation and obesity, but in our large ED population there was no significant impact of these factors on the diagnostic accuracy of CysC to detect AKI in ED patients.

Overoxidation of chloroplast 2-Cys peroxiredoxins: balancing toxic and signaling activities of hydrogen peroxide

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Leonor ePuerto-Galán

2013-08-01

Full Text Available Photosynthesis, the primary source of biomass and oxygen into the biosphere, involves the transport of electrons in the presence of oxygen and, therefore, chloroplasts constitute an important source of reactive oxygen species (ROS, including hydrogen peroxide. If accumulated at high level, hydrogen peroxide may exert a toxic effect; however, it is as well an important second messenger. In order to balance the toxic and signaling activities of hydrogen peroxide its level has to be tightly controlled. To this end, chloroplasts are equipped with different antioxidant systems such as 2-Cys peroxiredoxins (2-Cys Prxs, thiol-based peroxidases able to reduce hydrogen- and organic peroxides. At high peroxide concentrations the peroxidase function of 2-Cys Prxs may become inactivated through a process of overoxidation. This inactivation has been proposed to explain the signaling function of hydrogen peroxide in eukaryotes, whereas in prokaryotes, the 2-Cys Prxs of which were considered to be insensitive to overoxidation, the signaling activity of hydrogen peroxide is less relevant. Here we discuss the current knowledge about the mechanisms controlling 2-Cys Prx overoxidation in chloroplasts, organelles with an important signaling function in plants. Given the prokaryotic origin of chloroplasts, we discuss the occurrence of 2-Cys Prx overoxidation in cyanobacteria with the aim of identifying similarities between chloroplasts and their ancestors regarding their response to hydrogen peroxide.

A novel modified electrode as GC/PPy-AuNPs-rGO/L-Cys/Ag@MUA nanostructure configuration for determination of CCP and CRP antibodies in human blood serum samples.

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Babakhanian, Arash; Ehzari, Hosna; Kaki, Samineh; Hamidi, Zohreh

2015-01-15

In this work, silver nanoparticles were synthesized and stabilized with 11-mercaptoundecanoateanions to produce a new Ag@MUA core shell structure, and its utilizing for fabrication of a new sensing film. Gold nanoparticles (AuNPs) were electrochemically produced and simultaneously immobilized into the electropolymerized polypyrrole (PPy) film with the reduced graphene oxide (rGO). The Ag@MUA was then grafted to the surface of GC/PPy-AuNPs-rGO film using L-cysteine (L-Cys) linker agent and trifluoromethanesulfonic anhydride (TF2O), at ambient temperature and under the electrode stirring. The characterization of the sensor was studied by scanning electron microscopy, electrochemical impedance spectroscopy, cyclic and square wave voltammetry techniques. The utility of the modified electrode for clinical diagnosis has been successfully demonstrated by the analysis of human blood serums with a certified CRP and CCP content. Thus, the proposed sensor shows simple preparation, accuracy and precision in the analysis of cytochrome c protein (CCP) and C-reactive protein (CRP (with less side interferences. Copyright © 2014 Elsevier B.V. All rights reserved.

CysLT2 receptor activation is involved in LTC4-induced lung air-trapping in guinea pigs.

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Sekioka, Tomohiko; Kadode, Michiaki; Yonetomi, Yasuo; Kamiya, Akihiro; Fujita, Manabu; Nabe, Takeshi; Kawabata, Kazuhito

2017-01-05

CysLT 1 receptors are known to be involved in the pathogenesis of asthma. However, the functional roles of CysLT 2 receptors in this condition have not been determined. The purpose of this study is to develop an experimental model of CysLT 2 receptor-mediated LTC 4 -induced lung air-trapping in guinea pigs and use this model to clarify the mechanism underlying response to such trapping. Because LTC 4 is rapidly converted to LTD 4 by γ-glutamyltranspeptidase (γ-GTP) under physiological conditions, S-hexyl GSH was used as a γ-GTP inhibitor. In anesthetized artificially ventilated guinea pigs with no S-hexyl GSH treatment, i.v. LTC 4 -induced bronchoconstriction was almost completely inhibited by montelukast, a CysLT 1 receptor antagonist, but not by BayCysLT 2 RA, a CysLT 2 receptor antagonist. The inhibitory effect of montelukast was diminished by treatment with S-hexyl GSH, whereas the effect of BayCysLT 2 RA was enhanced with increasing dose of S-hexyl GSH. Macroscopic and histological examination of lung tissue isolated from LTC 4 -/S-hexyl-GSH-treated guinea pigs revealed air-trapping expansion, particularly at the alveolar site. Inhaled LTC 4 in conscious guinea pigs treated with S-hexyl GSH increased both airway resistance and airway hyperinflation. On the other hand, LTC 4 -induced air-trapping was only partially suppressed by treatment with the bronchodilator salmeterol. Although montelukast inhibition of LTC 4 -induced air-trapping was weak, treatment with BayCysLT 2 RA resulted in complete suppression of this air-trapping. Furthermore, BayCysLT 2 RA completely suppressed LTC 4 -induced airway vascular hyperpermeability. In conclusion, we found in this study that CysLT 2 receptors mediate LTC 4 -induced bronchoconstriction and air-trapping in S-hexyl GSH-treated guinea pigs. It is therefore believed that CysLT 2 receptors contribute to asthmatic response involving air-trapping. Copyright © 2016 Elsevier B.V. All rights reserved.

Selective desulfurization of cysteine in the presence of Cys(Acm) in polypeptides obtained by native chemical ligation.

Science.gov (United States)

Pentelute, Brad L; Kent, Stephen B H

2007-02-15

Increased versatility for the synthesis of proteins and peptides by native chemical ligation requires the ability to ligate at positions other than Cys. Here, we report that Raney nickel can be used under standard conditions for the selective desulfurization of Cys in the presence of Cys(Acm). This simple and practical tactic enables the more common Xaa-Ala junctions to be used as ligation sites for the chemical synthesis of Cys-containing peptides and proteins. [reaction: see text].

The Disulfide Bond Cys255-Cys279 in the Immunoglobulin-Like Domain of Anthrax Toxin Receptor 2 Is Required for Membrane Insertion of Anthrax Protective Antigen Pore.

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Pedro Jacquez

Full Text Available Anthrax toxin receptors act as molecular clamps or switches that control anthrax toxin entry, pH-dependent pore formation, and translocation of enzymatic moieties across the endosomal membranes. We previously reported that reduction of the disulfide bonds in the immunoglobulin-like (Ig domain of the anthrax toxin receptor 2 (ANTXR2 inhibited the function of the protective antigen (PA pore. In the present study, the disulfide linkage in the Ig domain was identified as Cys255-Cys279 and Cys230-Cys315. Specific disulfide bond deletion mutants were achieved by replacing Cys residues with Ala residues. Deletion of the disulfide bond C255-C279, but not C230-C315, inhibited the PA pore-induced release of the fluorescence dyes from the liposomes, suggesting that C255-C279 is essential for PA pore function. Furthermore, we found that deletion of C255-C279 did not affect PA prepore-to-pore conversion, but inhibited PA pore membrane insertion by trapping the PA membrane-inserting loops in proteinaceous hydrophobic pockets. Fluorescence spectra of Trp59, a residue adjacent to the PA-binding motif in von Willebrand factor A (VWA domain of ANTXR2, showed that deletion of C255-C279 resulted in a significant conformational change on the receptor ectodomain. The disulfide deletion-induced conformational change on the VWA domain was further confirmed by single-particle 3D reconstruction of the negatively stained PA-receptor heptameric complexes. Together, the biochemical and structural data obtained in this study provides a mechanistic insight into the role of the receptor disulfide bond C255-C279 in anthrax toxin action. Manipulation of the redox states of the receptor, specifically targeting to C255-C279, may become a novel strategy to treat anthrax.

The BARD1 Cys557Ser variant and breast cancer risk in Iceland.

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Simon N Stacey

2006-07-01

Full Text Available Most, if not all, of the cellular functions of the BRCA1 protein are mediated through heterodimeric complexes composed of BRCA1 and a related protein, BARD1. Some breast-cancer-associated BRCA1 missense mutations disrupt the function of the BRCA1/BARD1 complex. It is therefore pertinent to determine whether variants of BARD1 confer susceptibility to breast cancer. Recently, a missense BARD1 variant, Cys557Ser, was reported to be at increased frequencies in breast cancer families. We investigated the role of the BARD1 Cys557Ser variant in a population-based cohort of 1,090 Icelandic patients with invasive breast cancer and 703 controls. We then used a computerized genealogy of the Icelandic population to study the relationships between the Cys557Ser variant and familial clustering of breast cancer.The Cys557Ser allele was present at a frequency of 0.028 in patients with invasive breast cancer and 0.016 in controls (odds ratio [OR] = 1.82, 95% confidence interval [CI] 1.11-3.01, p = 0.014. The alleleic frequency was 0.037 in a high-predisposition group of cases defined by having a family history of breast cancer, early onset of breast cancer, or multiple primary breast cancers (OR = 2.41, 95% CI 1.22-4.75, p = 0.015. Carriers of the common Icelandic BRCA2 999del5 mutation were found to have their risk of breast cancer further increased if they also carried the BARD1 variant: the frequency of the BARD1 variant allele was 0.047 (OR = 3.11, 95% CI 1.16-8.40, p = 0.046 in 999del5 carriers with breast cancer. This suggests that the lifetime probability of a BARD1 Cys557Ser/BRCA2 999del5 double carrier developing breast cancer could approach certainty. Cys557Ser carriers, with or without the BRCA2 mutation, had an increased risk of subsequent primary breast tumors after the first breast cancer diagnosis compared to non-carriers. Lobular and medullary breast carcinomas were overrepresented amongst Cys557Ser carriers. We found that an excess of ancestors

No Impact of the Analytical Method Used for Determining Cystatin C on Estimating Glomerular Filtration Rate in Children.

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Alberer, Martin; Hoefele, Julia; Benz, Marcus R; Bökenkamp, Arend; Weber, Lutz T

2017-01-01

Measurement of inulin clearance is considered to be the gold standard for determining kidney function in children, but this method is time consuming and expensive. The glomerular filtration rate (GFR) is on the other hand easier to calculate by using various creatinine- and/or cystatin C (Cys C)-based formulas. However, for the determination of serum creatinine (Scr) and Cys C, different and non-interchangeable analytical methods exist. Given the fact that different analytical methods for the determination of creatinine and Cys C were used in order to validate existing GFR formulas, clinicians should be aware of the type used in their local laboratory. In this study, we compared GFR results calculated on the basis of different GFR formulas and either used Scr and Cys C values as determined by the analytical method originally employed for validation or values obtained by an alternative analytical method to evaluate any possible effects on the performance. Cys C values determined by means of an immunoturbidimetric assay were used for calculating the GFR using equations in which this analytical method had originally been used for validation. Additionally, these same values were then used in other GFR formulas that had originally been validated using a nephelometric immunoassay for determining Cys C. The effect of using either the compatible or the possibly incompatible analytical method for determining Cys C in the calculation of GFR was assessed in comparison with the GFR measured by creatinine clearance (CrCl). Unexpectedly, using GFR equations that employed Cys C values derived from a possibly incompatible analytical method did not result in a significant difference concerning the classification of patients as having normal or reduced GFR compared to the classification obtained on the basis of CrCl. Sensitivity and specificity were adequate. On the other hand, formulas using Cys C values derived from a compatible analytical method partly showed insufficient

Low-energy shock wave preconditioning reduces renal ischemic reperfusion injury caused by renal artery occlusion.

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Xue, Yuquan; Xu, Zhibin; Chen, Haiwen; Gan, Weimin; Chong, Tie

2017-07-01

To evaluate whether low energy shock wave preconditioning could reduce renal ischemic reperfusion injury caused by renal artery occlusion. The right kidneys of 64 male Sprague Dawley rats were removed to establish an isolated kidney model. The rats were then divided into four treatment groups: Group 1 was the sham treatment group; Group 2, received only low-energy (12 kv, 1 Hz, 200 times) shock wave preconditioning; Group 3 received the same low-energy shock wave preconditioning as Group 2, and then the left renal artery was occluded for 45 minutes; and Group 4 had the left renal artery occluded for 45 minutes. At 24 hours and one-week time points after reperfusion, serum inducible nitric oxide synthase (iNOS), neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), creatinine (Cr), and cystatin C (Cys C) levels were measured, malondialdehyde (MDA) in kidney tissue was detected, and changes in nephric morphology were evaluated by light and electron microscopy. Twenty-four hours after reperfusion, serum iNOS, NGAL, Cr, Cys C, and MDA levels in Group 3 were significantly lower than those in Group 4; light and electron microscopy showed that the renal tissue injury in Group 3 was significantly lighter than that in Group 4. One week after reperfusion, serum NGAL, KIM-1, and Cys C levels in Group 3 were significantly lower than those in Group 4. Low-energy shock wave preconditioning can reduce renal ischemic reperfusion injury caused by renal artery occlusion in an isolated kidney rat model.

A glycine residue essential for high ivermectin sensitivity in Cys-loop ion channel receptors

DEFF Research Database (Denmark)

Lynagh, Timothy; Lynch, Joseph W.

2010-01-01

Ivermectin exerts its anthelmintic effect by activating nematode Cys-loop glutamate-gated receptors. Here we show that a glycine residue at a specific transmembrane domain location is essential for high ivermectin sensitivity in both glycine- and glutamate-gated Cys-loop receptors. We also show...

Modification of Cys-418 of pyruvate formate-lyase by methacrylic acid, based on its radical mechanism.

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Plaga, W; Vielhaber, G; Wallach, J; Knappe, J

2000-01-21

The recently determined crystal structure of pyruvate formate-lyase (PFL) suggested a new view of the mechanism of this glycyl radical enzyme, namely that intermediary thiyl radicals of Cys-418 and Cys-419 participate in different ways [Becker, A. et al. (1999) Nat. Struct. Biol. 6, 969-975]. We report here a suicide reaction of PFL that occurs with the substrate-analog methacrylate with retention of the protein radical (K(I)=0.42 mM, k(i)=0.14 min(-1)). Using [1-(14)C]methacrylate (synthesized via acetone cyanhydrin), the reaction end-product was identified by peptide mapping and cocrystallization experiments as S-(2-carboxy-(2S)-propyl) substituted Cys-418. The stereoselectivity of the observed Michael addition reaction is compatible with a radical mechanism that involves Cys-418 thiyl as nucleophile and Cys-419 as H-atom donor, thus supporting the functional assignments of these catalytic amino acid residues derived from the protein structure.

Cys-X scanning for expansion of active-site residues and modulation of catalytic functions in a glutathione transferase.

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Norrgård, Malena A; Hellman, Ulf; Mannervik, Bengt

2011-05-13

We propose Cys-X scanning as a semisynthetic approach to engineer the functional properties of recombinant proteins. As in the case of Ala scanning, key residues in the primary structure are identified, and one of them is replaced by Cys via site-directed mutagenesis. The thiol of the residue introduced is subsequently modified by alternative chemical reagents to yield diverse Cys-X mutants of the protein. This chemical approach is orthogonal to Ala or Cys scanning and allows the expansion of the repertoire of amino acid side chains far beyond those present in natural proteins. In its present application, we have introduced Cys-X residues in human glutathione transferase (GST) M2-2, replacing Met-212 in the substrate-binding site. To achieve selectivity of the modifications, the Cys residues in the wild-type enzyme were replaced by Ala. A suite of simple substitutions resulted in a set of homologous Met derivatives ranging from normethionine to S-heptyl-cysteine. The chemical modifications were validated by HPLC and mass spectrometry. The derivatized mutant enzymes were assayed with alternative GST substrates representing diverse chemical reactions: aromatic substitution, epoxide opening, transnitrosylation, and addition to an ortho-quinone. The Cys substitutions had different effects on the alternative substrates and differentially enhanced or suppressed catalytic activities depending on both the Cys-X substitution and the substrate assayed. As a consequence, the enzyme specificity profile could be changed among the alternative substrates. The procedure lends itself to large-scale production of Cys-X modified protein variants.

Principles of agonist recognition in Cys-loop receptors

DEFF Research Database (Denmark)

Lynagh, Timothy Peter; Pless, Stephan Alexander

2014-01-01

, functional studies, and X-ray crystallography experiments identified the extracellular interface of adjacent subunits as the principal site of agonist binding. The question of how subtle differences at and around agonist-binding sites of different Cys-loop receptors can accommodate transmitters as chemically...

Effects of Oral Prednisone Administration on Serum Cystatin C in Dogs.

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Muñoz, J; Soblechero, P; Duque, F J; Macías-García, B; Ruiz, P; Zaragoza, C; Barrera, R

2017-11-01

Oral administration of glucocorticoid alters serum cystatin C (sCysC) concentration in humans. To determine if oral administration of prednisone alters sCysC in dogs without pre-existing renal disease. Forty six dogs were included: 10 dogs diagnosed with steroid responsive meningitis arteritis (SRMA; group A), 20 dogs diagnosed of pituitary-dependent hyperadrenocorticism (PDH; group B), and 16 healthy control dogs (group C). Retrospective observational study. SRMA diagnosed dogs were administered prednisone 4 mg/kg/24 h PO 7 days, reducing the dose to 2 mg/kg/24 h 7 days before medication withdrawal. In group A, sampling was performed at days 0, 7, 14 and a final control at day 21. Blood and urine samples were collected in the 3 groups, and in group A, sampling was performed at all time points (days 1, 7, 14, and 21). In group A, sCysC was significantly higher at day 7 compared to the control group (0.4 ± 0.04 mg/L vs. 0.18 ± 0.03 mg/L mean ± SEM respectively P 0.05). Dogs with PDH included in group B did not have significant differences in sCysC (0.22 ± 0.03 mg/L) compared to control (P > 0.05). Oral administration of prednisone unlike altered endogenous glucocorticoid production, increases sCysC in dogs in a dose-dependent fashion. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Two-dimensional 1H and 31P NMR spectra of a decamer oligodeoxyribonucleotide duplex and a quinoxaline ([MeCys3, MeCys7]TANDEM) drug duplex complex

International Nuclear Information System (INIS)

Powers, R.; Olsen, R.K.; Gorenstein, D.G.

1989-01-01

Assignment of the 1H and 31P NMR spectra of a decamer oligodeoxyribonucleotide duplex, d(CCCGATCGGG), and its quinoxaline ([MeCys3, MeCys7]TANDEM) drug duplex complex has been made by two-dimensional 1H-1H and heteronuclear 31P-1H correlated spectroscopy. The 31P chemical shifts of this 10 base pair oligonucleotide follow the general observation that the more internal the phosphate is located within the oligonucleotide sequence, the more upfield the 31P resonance occurs. While the 31P chemical shifts show sequence-specific variations, they also do not generally follow the Calladine rules previously demonstrated. 31P NMR also provides a convenient monitor of the phosphate ester backbone conformational changes upon binding of the drug to the duplex. Although the quinoxaline drug, [MeCys3, MeCys7]TANDEM, is generally expected to bind to duplex DNA by bis-intercalation, only small 31P chemical shift changes are observed upon binding the drug to duplex d(CCCGATCGGG). Additionally, only small perturbations in the 1H NMR and UV spectra are observed upon binding the drug to the decamer, although association of the drug stabilizes the duplex form relative to the other states. These results are consistent with a non-intercalative mode of association of the drug. Modeling and molecular mechanics energy minimization demonstrate that a novel structure in which the two quinoxaline rings of the drug binds in the minor groove of the duplex is possible

Evaluation of Serum Cystatin C compared with Creatinine: A study in patients with Pre-eclampsia

OpenAIRE

Salma Malik Mmordas; Omer Fadol Edris

2015-01-01

This is cross sectional study aim to evaluate of serum Cystatin C and Creatinine level among pre-clampsia patients. Hundred subjects were evaluate in this study, 50 preclampsia patients as cases and 50 healthy apparently as control groups. Serum Cystatin C and Creatinine were measuring using MISP-i2, Mindray respectively. In assessment of renal function and compare with creatin in women which diagnostic   preeclampsia.  Result showed there was significant increase in mean concentration of Cys...

A water-soluble and retrievable ruthenium-based probe for colorimetric recognition of Hg(II) and Cys.

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Cui, Yali; Hao, Yuanqiang; Zhang, Yintang; Liu, Baoxia; Zhu, Xu; Qu, Peng; Li, Deliang; Xu, Maotian

2016-08-05

A new ruthenium-based complex 1 [(bis(4,4'-dimethylphosphonic-2,2'-bipyridine) dithiocyanato ruthenium (II))] was developed as a colorimetric probe for the detection of Hg(II) and Cys (Cysteine). The obtained compound 1 can give interconversional color changes upon the alternating addition of Hg(II) and Cys in 100% aqueous solution. The specific coordination between NCS groups with Hg(II) can lead to the formation of 1-Hg(2+) complex, which can induce a remarkable spectral changes of probe 1. Afterwards the formed 1-Hg(2+) complex can act as effective colorimetric sensor for Cys. Owing to the stronger binding affinity of sulfhydryl group to Hg(2+), Cys can extract Hg(2+) from 1-Hg(2+) complex resulting in the release of 1 and the revival of absorption profile of the probe 1. By introducing the hydrophilic phosphonic acid groups, the proposed probe exhibited excellent water solubility. The limits of detection (LODs) of the assay for Hg(2+) and Cys are calculated to be 15nM and 200nM, respectively. Copyright © 2016. Published by Elsevier B.V.

Estimating renal function in children: a new GFR-model based on serum cystatin C and body cell mass.

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Andersen, Trine Borup

2012-07-01

This PhD thesis is based on four individual studies including 131 children aged 2-14 years with nephro-urologic disorders. The majority (72%) of children had a normal renal function (GFR > 82 ml/min/1.73 square metres), and only 8% had a renal function thesis´ main aims were: 1) to develop a more accurate GFR model based on a novel theory of body cell mass (BCM) and cystatin C (CysC); 2) to investigate the diagnostic performance in comparison to other models as well as serum CysC and creatinine; 3) to validate the new models precision and validity. The model´s diagnostic performance was investigated in study I as the ability to detect changes in renal function (total day-to-day variation), and in study IV as the ability to discriminate between normal and reduced function. The model´s precision and validity were indirectly evaluated in study II and III, and in study I accuracy was estimated by comparison to reference GFR. Several prediction models based on CysC or a combination of CysC and serum creatinine have been developed for predicting GFR in children. Despite these efforts to improve GFR estimates, no alternative to exogenous methods has been found and the Schwartz´s formula based on height, creatinine and an empirically derived constant is still recommended for GFR estimation in children. However, the inclusion of BCM as a possible variable in a CysC-based prediction model has not yet been explored. As CysC is produced at a constant rate from all nucleated cells we hypothesize that including BCM in a new prediction model will increase accuracy of the GFR estimate. Study I aimed at deriving the new GFR-prediction model based on the novel theory of CysC and BCM and comparing the performance to previously published models. The BCM-model took the form GFR (mL/min) = 10.2 × (BCM/CysC)E 0.40 × (height × body surface area/Crea)E 0.65. The model predicted 99% within ± 30% of reference GFR, and 67% within ±10%. This was higher than any other model. The

Does NGAL reduce costs? A cost analysis of urine NGAL (uNGAL) & serum creatinine (sCr) for acute kidney injury (AKI) diagnosis.

Science.gov (United States)

Parikh, Amay; Rizzo, John A; Canetta, Pietro; Forster, Catherine; Sise, Meghan; Maarouf, Omar; Singer, Eugenia; Elger, Antje; Elitok, Saban; Schmidt-Ott, Kai; Barasch, Jonathon; Nickolas, Thomas L

2017-01-01

Urine neutrophil gelatinase-associated lipocalin (uNGAL) is a sensitive and specific diagnostic test for acute kidney injury (AKI) in the Emergency Department (ED), but its economic impact has not been investigated. We hypothesized that uNGAL used in combination with serum creatinine (sCr) would reduce costs in the management of AKI in patients presenting to the ED in comparison to using sCr alone. A cost simulation model was developed for clinical algorithms to diagnose AKI based on sCr alone vs. uNGAL plus sCr (uNGAL+sCr). A cost minimization analysis was performed to determine total expected costs for patients with AKI. uNGAL test characteristics were validated with eight-hundred forty-nine patients with sCr ≥1.5 from a completed study of 1635 patients recruited from EDs at two U.S. hospitals from 2007-8. Biomarker test, AKI work-up, and diagnostic imaging costs were incorporated. For a hypothetical cohort of 10,000 patients, the model predicted that the expected costs were $900 per patient (pp) in the sCr arm and $950 in the uNGAL+sCr arm. uNGAL+sCr resulted in 1,578 fewer patients with delayed diagnosis and treatment than sCr alone (2,013 vs. 436 pts) at center 1 and 1,973 fewer patients with delayed diagnosis and treatment than sCr alone at center 2 (2,227 vs. 254 patients). Although initial evaluation costs at each center were $50 pp higher in with uNGAL+sCr, total costs declined by $408 pp at Center 1 and by $522 pp at Center 2 due to expected reduced delays in diagnosis and treatment. Sensitivity analyses confirmed savings with uNGAL + sCr for a range of cost inputs. Using uNGAL with sCr as a clinical diagnostic test for AKI may improve patient management and reduce expected costs. Any cost savings would likely result from avoiding delays in diagnosis and treatment and from avoidance of unnecessary testing in patients given a false positive AKI diagnosis by use of sCr alone.

Does NGAL reduce costs? A cost analysis of urine NGAL (uNGAL & serum creatinine (sCr for acute kidney injury (AKI diagnosis.

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Amay Parikh

Full Text Available Urine neutrophil gelatinase-associated lipocalin (uNGAL is a sensitive and specific diagnostic test for acute kidney injury (AKI in the Emergency Department (ED, but its economic impact has not been investigated. We hypothesized that uNGAL used in combination with serum creatinine (sCr would reduce costs in the management of AKI in patients presenting to the ED in comparison to using sCr alone.A cost simulation model was developed for clinical algorithms to diagnose AKI based on sCr alone vs. uNGAL plus sCr (uNGAL+sCr. A cost minimization analysis was performed to determine total expected costs for patients with AKI. uNGAL test characteristics were validated with eight-hundred forty-nine patients with sCr ≥1.5 from a completed study of 1635 patients recruited from EDs at two U.S. hospitals from 2007-8. Biomarker test, AKI work-up, and diagnostic imaging costs were incorporated.For a hypothetical cohort of 10,000 patients, the model predicted that the expected costs were $900 per patient (pp in the sCr arm and $950 in the uNGAL+sCr arm. uNGAL+sCr resulted in 1,578 fewer patients with delayed diagnosis and treatment than sCr alone (2,013 vs. 436 pts at center 1 and 1,973 fewer patients with delayed diagnosis and treatment than sCr alone at center 2 (2,227 vs. 254 patients. Although initial evaluation costs at each center were $50 pp higher in with uNGAL+sCr, total costs declined by $408 pp at Center 1 and by $522 pp at Center 2 due to expected reduced delays in diagnosis and treatment. Sensitivity analyses confirmed savings with uNGAL + sCr for a range of cost inputs.Using uNGAL with sCr as a clinical diagnostic test for AKI may improve patient management and reduce expected costs. Any cost savings would likely result from avoiding delays in diagnosis and treatment and from avoidance of unnecessary testing in patients given a false positive AKI diagnosis by use of sCr alone.

The hOGG1 Ser326Cys Gene Polymorphism and Breast Cancer Risk in Saudi Population.

Science.gov (United States)

Alanazi, Mohammed; Pathan, Akbar Ali Khan; Shaik, Jilani P; Alhadheq, Abdullah; Khan, Zahid; Khan, Wajahatullah; Al Naeem, Abdulrahman; Parine, Narasimha Reddy

2017-07-01

The purpose of this study was to test the association between human 8-oxoguanine glycosylase 1 (hOGG1) gene polymorphisms and susceptibility to breast cancer in Saudi population. We have also aimed to screen the hOGG1 Ser326Cys polymorphism effect on structural and functional properties of the hOGG1 protein using in silico tools. We have analyzed four SNPs of hOGG1 gene among Saudi breast cancer patients along with healthy controls. Genotypes were screened using TaqMan SNP genotype analysis method. Experimental data was analyzed using Chi-square, t test and logistic regression analysis using SPSS software (v.16). In silco analysis was conducted using discovery studio and HOPE program. Genotypic analysis showed that hOGG1 rs1052133 (Ser326Cys) is significantly associated with breast cancer samples in Saudi population, however rs293795 (T >C), rs2072668 (C>G) and rs2075747 (G >A) did not show any association with breast cancer. The hOGG1 SNP rs1052133 (Ser326Cys) minor allele T showed a significant association with breast cancer samples (OR = 1.78, χ2 = 7.86, p = 0.02024). In silico structural analysis was carried out to compare the wild type (Ser326) and mutant (Cys326) protein structures. The structural prediction studies revealed that Ser326Cys variant may destabilize the protein structure and it may disturb the hOGG1 function. Taken together this is the first In silico study report to confirm Ser326Cys variant effect on structural and functional properties of hOGG1 gene and Ser326Cys role in breast cancer susceptibility in Saudi population.

CysQ of , a Protozoa, May Have Been Acquired from Bacteria by Horizontal Gene Transfer

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Ji Young Lee

2012-03-01

Full Text Available Horizontal gene transfer (HGT is the movement of genetic material between kingdoms and is considered to play a positive role in adaptation. Cryptosporidium parvum is a parasitic protozoan that causes an infectious disease. Its genome sequencing reported 14 bacteria-like proteins in the nuclear genome. Among them, cgd2_1810, which has been annotated as CysQ, a sulfite synthesis pathway protein, is listed as one of the candidates of genes horizontally transferred from bacterial origin. In this report, we examined this issue using phylogenetic analysis. Our BLAST search showed that C. parvum CysQ protein had the highest similarity with that of proteobacteria. Analysis with NCBI's Conserved Domain Tree showed phylogenetic incongruence, in that C. parvum CysQ protein was located within a branch of proteobacteria in the cd01638 domain, a bacterial member of the inositol monophosphatase family. According to Kyoto Encyclopedia of Genes and Genomes (KEGG pathway, the sulfate assimilation pathway, where CysQ plays an important role, is well conserved in most eukaryotes as well as prokaryotes. However, the Apicomplexa, including C. parvum, largely lack orthologous genes of the pathway, suggesting its loss in those protozoan lineages. Therefore, we conclude that C. parvum regained cysQ from proteobacteria by HGT, although its functional role is elusive.

Isolation of Nicotiana plumbaginifolia cDNAs encoding isoforms of serine acetyltransferase and O-acetylserine (thiol) lyase in a yeast two-hybrid system with Escherichia coli cysE and cysK genes as baits.

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Liszewska, Frantz; Gaganidze, Dali; Sirko, Agnieszka

2005-01-01

We applied the yeast two-hybrid system for screening of a cDNA library of Nicotiana plumbaginifolia for clones encoding plant proteins interacting with two proteins of Escherichia coli: serine acetyltransferase (SAT, the product of cysE gene) and O-acetylserine (thiol)lyase A, also termed cysteine synthase (OASTL-A, the product of cysK gene). Two plant cDNA clones were identified when using the cysE gene as a bait. These clones encode a probable cytosolic isoform of OASTL and an organellar isoform of SAT, respectively, as indicated by evolutionary trees. The second clone, encoding SAT, was identified independently also as a "prey" when using cysK as a bait. Our results reveal the possibility of applying the two-hybrid system for cloning of plant cDNAs encoding enzymes of the cysteine synthase complex in the two-hybrid system. Additionally, using genome walking sequences located upstream of the sat1 cDNA were identified. Subsequently, in silico analyses were performed aiming towards identification of the potential signal peptide and possible location of the deduced mature protein encoded by sat1.

Chloroplast NADPH-Dependent Thioredoxin Reductase from Chlorella vulgaris Alleviates Environmental Stresses in Yeast Together with 2-Cys Peroxiredoxin

Science.gov (United States)

Machida, Takeshi; Ishibashi, Akiko; Kirino, Ai; Sato, Jun-ichi; Kawasaki, Shinji; Niimura, Youichi; Honjoh, Ken-ichi; Miyamoto, Takahisa

2012-01-01

Chloroplast NADPH-dependent thioredoxin reductase (NTRC) catalyzes the reduction of 2-Cys peroxiredoxin (2-Cys Prx) and, thus, probably functions as an antioxidant system. The functions of the enzyme in oxidative and salt stresses have been reported previously. We have previously identified and characterized NTRC in Chlorella vulgaris. In the present study, we isolated a full-length cDNA clone encoding 2-Cys Prx from C. vulgaris and investigated the involvement of Chlorella NTRC/2-Cys Prx system in several environmental stress tolerances by using yeast as a eukaryotic model. Deduced Chlorella 2-Cys Prx was homologous to those of chloroplast 2-Cys Prxs from plants, and two conserved cysteine residues were found in the deduced sequence. Enzyme assay showed that recombinant mature C. vulgaris NTRC (mCvNTRC) transferred electrons from NADPH to recombinant mature C. vulgaris 2-Cys Prx (mCvPrx), and mCvPrx decomposed hydrogen peroxide, tert-butyl hydroperoxide, and peroxynitrite by cooperating with mCvNTRC. Based on the results, the mCvNTRC/mCvPrx antioxidant system was identified in Chlorella. The antioxidant system genes were expressed in yeast separately or coordinately. Stress tolerances of yeast against freezing, heat, and menadione-induced oxidative stresses were significantly improved by expression of mCvNTRC, and the elevated tolerances were more significant when both mCvNTRC and mCvPrx were co-expressed. Our results reveal a novel feature of NTRC: it functions as an antioxidant system with 2-Cys Prx in freezing and heat stress tolerances. PMID:23029353

The C-type Arabidopsis thioredoxin reductase ANTR-C acts as an electron donor to 2-Cys peroxiredoxins in chloroplasts

International Nuclear Information System (INIS)

Moon, Jeong Chan; Jang, Ho Hee; Chae, Ho Byoung; Lee, Jung Ro; Lee, Sun Yong; Jung, Young Jun; Shin, Mi Rim; Lim, Hye Song; Chung, Woo Sik; Yun, Dae-Jin; Lee, Kyun Oh; Lee, Sang Yeol

2006-01-01

2-Cys peroxiredoxins (Prxs) play important roles in the antioxidative defense systems of plant chloroplasts. In order to determine the interaction partner for these proteins in Arabidopsis, we used a yeast two-hybrid screening procedure with a C175S-mutant of Arabidopsis 2-Cys Prx-A as bait. A cDNA encoding an NADPH-dependent thioredoxin reductase (NTR) isotype C was identified and designated ANTR-C. We demonstrated that this protein effected efficient transfer of electrons from NADPH to the 2-Cys Prxs of chloroplasts. Interaction between 2-Cys Prx-A and ANTR-C was confirmed by a pull-down experiment. ANTR-C contained N-terminal TR and C-terminal Trx domains. It exhibited both TR and Trx activities and co-localized with 2-Cys Prx-A in chloroplasts. These results suggest that ANTR-C functions as an electron donor for plastidial 2-Cys Prxs and represents the NADPH-dependent TR/Trx system in chloroplasts

HPLC separation of human serum albumin isoforms based on their isoelectric points

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Bonilla, Lucía; Torres, María José; Schopfer, Francisco; Freeman, Bruce A.; Armas, Larissa; Ricciardi, Alejandro; Alvarez, Beatriz; Radi, Rafael

2014-01-01

Human serum albumin (HSA) is the most abundant protein in plasma. Cys34, the only free Cys residue, is the predominant plasma thiol and a relevant sacrificial antioxidant. Both in vivo circulating HSA and pharmaceutical preparations are heterogeneous with respect to the oxidation state of Cys34. In this work, we developed an external pH gradient chromatofocusing procedure that allows the analysis of the oxidation status of HSA in human plasma and biopharmaceutical products based on the different apparent isoelectric points and chemical properties of the redox isoforms. Specifically, reduced-mercury blocked HSA (HSA–SHg+), HSA with Cys34 oxidized to sulfenic acid (HSA–SOH) and HSA oxidized to sulfinate anion (HSA–SO2−) can be separated with resolutions of 1.4 and 3.1 (first and last pair) and hence quantified and purified. In addition, an N-terminally degraded isoform (HSA3–585) in different redox states can be resolved as well. Confirmation of the identity of the chromatofocusing isolated isoforms was achieved by high resolution whole protein MS. It is proposed that the chromatofocusing procedure can be used to produce more exact and complete descriptions of the redox status of HSA in vivo and in vitro. Finally, the scalability capabilities of the chromatofocusing procedure allow for the preparation of highly pure standards of several redox isoforms of HSA PMID:24316526

A role for inflammatory mediators in heterologous desensitization of CysLT1 receptor in human monocytes

Science.gov (United States)

Capra, Valérie; Accomazzo, Maria Rosa; Gardoni, Fabrizio; Barbieri, Silvia; Rovati, G. Enrico

2010-01-01

Cysteinyl-leukotrienes (cysteinyl-LT) are rapidly generated at sites of inflammation and, in addition to their role in asthma, rhinitis, and other immune disorders, are increasingly regarded as significant inflammatory factors in cancer, gastrointestinal, cardiovascular diseases. We recently demonstrated that in monocyte/macrophage–like U937 cells, extracellular nucleotides heterologously desensitize CysLT1 receptor (CysLT1R)-induced Ca2+ transients. Given that monocytes express a number of other inflammatory and chemoattractant receptors, this study was aimed at characterizing transregulation between these different stimuli. We demonstrate that in U937 cells and in primary human monocytes, a series of inflammatory mediators activating Gi-coupled receptor (FPR1, BLT1) desensitize CysLT1R-induced Ca2+ response unidirectionally through activation of PKC. Conversely, PAF-R, exclusively coupled to Gq, cross-desensitizes CysLT1R without the apparent involvement of any kinase. Interestingly, Gs-coupled receptors (β2AR, H1/2R, EP2/4R) are also able to desensitize CysLT1R response through activation of PKA. Heterologous desensitization seems to affect mostly the Gi-mediated signaling of the CysLT1R. The hierarchy of desensitization among agonists may be important for leukocyte signal processing at the site of inflammation. Considering that monocytes/macrophages are likely to be the major source of cysteinyl-LT in many immunological and inflammatory processes, shedding light on how their receptors are regulated will certainly help to better understand the role of these cells in orchestrating this complex network of integrated signals. PMID:19965602

Multicenter study of creatinine- and/or cystatin C-based equations for estimation of glomerular filtration rates in Chinese patients with chronic kidney disease.

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Jia-fu Feng

Full Text Available OBJECTIVE: To establish equations for the estimation of glomerular filtration rates (eGFRs based on serum creatinine (SCr and/or serum cystatin C (SCysC in Chinese patients with chronic kidney disease (CKD, and to compare the new equations with both the reference GFR (rGFR and the literature equations to evaluate their applicability. METHODS: The 788 Chinese CKD patients were randomly divided into two groups, the training group and the testing group, to establish new eGFR-formulas based on serum CysC and to validate the established formulas, respectively. (99mTc-DTPA clearance (as the rGFR, serum Cr, and serum CysC were determined for all patients, and GFR was calculated using the Cockcroft-Gault equation (eGFR1, the MDRD formula (eGFR2, the CKD-EPI formulas (eGFR3, eGFR4, and the Chinese eGFR Investigation Collaboration formulas (eGFR5, eGFR6. The accuracy of each eGFR was compared with the rGFR. RESULTS: The training and testing groups' mean GFRs were 50.84±31.36 mL/min/1.73 m(2 and 54.16±29.45 mL/min/1.73 m(2, respectively. The two newly developed eGFR formulas were fitted using iterative computation: [Formula: see text] and [Formula: see text]. Significant correlation was observed between each eGFR and the rGFR. However, proportional errors and constant errors were observed between rGFR and eGFR1, eGFR2, eGFR4, eGFR5 or eGFR6, and constant errors were observed between eGFR3 and rGFR, as revealed by the Passing & Bablok plot analysis. The Bland-Altman analysis illustrated that the 95% limits of agreement of all equations exceeded the previously accepted limits of <60 mL/min •1.73 m(2, except the equations of eGFR7 and eGFR8. CONCLUSION: The newly developed formulas, eGFR7 and eGFR8, provide precise and accurate GFR estimation using serum CysC detection alone or in combination with serum Cr detection. Differences in detection methods should be carefully considered when choosing literature eGFR equations to avoid misdiagnosis and

Cystatin C–Adiponectin Complex in Plasma Associates with Coronary Plaque Instability

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Matsuoka, Tetsuro; Kayama, Kento; Onishi, Sumire; Matsuo, Natsumi

2017-01-01

Aim: Adiponectin (APN) is an adipocyte-derived bioactive molecule with antiatherogenic properties. We previously reported that cystatin C (CysC) abolished the anti-atherogenic effects of APN. We aimed to elucidate the clinical significance of CysC–APN complex in patients with coronary artery disease (CAD). Methods: We enrolled 43 stable CAD male patients to examine the relationship between CysC–APN complex and coronary plaque characteristics. Serum was immunoprecipitated by the anti-APN antibody and immunoblotted by the anti-CysC antibody to demonstrate the presence of CysC–APN complexes in vivo. To confirm their binding in vitro, HEK293T cell lysates overexpressing myc-APN and FLAG-CysC were immunoprecipitated with an anti-myc or anti-FLAG antibody, followed by immunoblotting with an anti-APN or anti-CysC antibody. Results: CysC was identified as a specific co-immunoprecipitant with APN by the anti-APN antibody in human serum. In vitro, FLAG-CysC was co-immunoprecipitated with myc-APN by the antimyc antibody and myc-APN was co-immunoprecipitated with FLAG-CysC by the anti-FLAG antibody. Among CAD patients, serum CysC–APN complex levels negatively correlated with fibrotic components of coronary plaques and positively correlated with either necrotic or lipidic plus necrotic components. Plaque burden negatively correlated with serum APN levels but not serum CysC–APN complex levels. Serum CysC levels had no association with plaque characteristics. In multivariate analysis, CysC–APN complex levels were identified as the strongest negative factor for fibrotic components and the strongest positive factor for both necrotic and lipidic plus necrotic components. Conclusion: Measuring serum CysC–APN complex levels is helpful for evaluating coronary plaque instability in CAD patients. PMID:28321013

Association between serum soluble CD30 and serum creatinine before and after renal transplantation.

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López-Hoyos, M; San Segundo, D; Benito, M J; Fernández-Fresnedo, G; Ruiz, J C; Rodrigo, E; Gómez-Alamillo, C; Benito, A; Arias, M

2008-11-01

There is increasing evidence that circulating levels of soluble CD30 (sCD30) may represent a biomarker for outcome in kidney transplantation. The aim of this study was to measure the pre- and posttransplantation serum levels of sCD30 in cadaveric kidney transplant recipients and correlate them with serum creatinine. Serum sCD30 was measured by a commercial enzyme-linked immunosorbent assay (ELISA) from prospective samples of 38 kidney allograft recipients serially transplanted at our center. Samples were collected at day 0 pretransplantation and at months 6, 12, 18, and 24 posttransplantation. We also studied sera from 29 patients with chronic kidney disease (CKD) at different stages of the K/DOQI guidelines, as a control group. Serum levels of sCD30 decreased significantly in samples posttransplantation compared with pretransplantation. The significant decrease after transplantation may be related to the improvement in renal function since we observed a significant correlation between serum levels of sCD30 and creatinine (sCr) at all times of the study. In addition, the patients with chronic renal failure showed a significant association between serum sCD30 and sCr (r = .454; P = .013). Our results did not suggest that the measurement of sCD30 may be used as a valuable biomarker in renal transplantation. Increased levels may be related to a decrease in its renal elimination.

Hydrogen Sulfide Targets the Cys320/Cys529 Motif in Kv4.2 to Inhibit the Ito Potassium Channels in Cardiomyocytes and Regularizes Fatal Arrhythmia in Myocardial Infarction

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Ma, Shan-Feng; Luo, Yan; Ding, Ying-Jiong; Chen, Ying; Pu, Shi-Xin; Wu, Hang-Jing; Wang, Zhong-Feng; Tao, Bei-Bei; Wang, Wen-Wei

2015-01-01

Abstract Aims: The mechanisms underlying numerous biological roles of hydrogen sulfide (H2S) remain largely unknown. We have previously reported an inhibitory role of H2S in the L-type calcium channels in cardiomyocytes. This prompts us to examine the mechanisms underlying the potential regulation of H2S on the ion channels. Results: H2S showed a novel inhibitory effect on Ito potassium channels, and this effect was blocked by mutation at the Cys320 and/or Cys529 residues of the Kv4.2 subunit. H2S broke the disulfide bridge between a pair of oxidized cysteine residues; however, it did not modify single cysteine residues. H2S extended action potential duration in epicardial myocytes and regularized fatal arrhythmia in a rat model of myocardial infarction. H2S treatment significantly increased survival by ∼1.4-fold in the critical 2-h time window after myocardial infarction with a protection against ventricular premature beats and fatal arrhythmia. However, H2S did not change the function of other ion channels, including IK1 and INa. Innovation and Conclusion: H2S targets the Cys320/Cys529 motif in Kv4.2 to regulate the Ito potassium channels. H2S also shows a potent regularizing effect against fatal arrhythmia in a rat model of myocardial infarction. The study provides the first piece of evidence for the role of H2S in regulating Ito potassium channels and also the specific motif in an ion channel labile for H2S regulation. Antioxid. Redox Signal. 23, 129–147. PMID:25756524

The hOGG1 Ser326Cys polymorphism contributes to digestive system cancer susceptibility: evidence from 48 case-control studies.

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Wang, Yang; Gao, Xujie; Wei, Feng; Zhang, Xinwei; Yu, Jinpu; Zhao, Hua; Sun, Qian; Yan, Fan; Yan, Cihui; Li, Hui; Ren, Xiubao

2015-02-01

The Ser326Cys polymorphism in the human 8-oxogunaine DNA glycosylase (hOGG1) gene had been implicated in cancer susceptibility. Studies investigating the associations between the Ser326Cys polymorphism and digestion cancer susceptibility showed conflicting results. Therefore, a meta-analysis was performed to derive a more precise estimation of the relationship. We conducted a meta-analysis of 48 studies that included 12,073 cancer cases and 19,557 case-free controls. We assessed the strength of the association using odds ratios (ORs) with 95% confidence intervals (CIs). In our analysis, the hOGG1 Ser326Cys polymorphism was significantly associated with the risk of digestive system cancers (Cys/Cys vs. Ser/Ser: OR = 1.17, 95% CI = 1.00-1.35, P digestive cancers.

Proteomic identification of an embryo-specific 1Cys-Prx promoter and analysis of its activity in transgenic rice.

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Kim, Je Hein; Jung, In Jung; Kim, Dool Yi; Fanata, Wahyu Indra; Son, Bo Hwa; Yoo, Jae Yong; Harmoko, Rikno; Ko, Ki Seong; Moon, Jeong Chan; Jang, Ho Hee; Kim, Woe Yeon; Kim, Jae-Yean; Lim, Chae Oh; Lee, Sang Yeol; Lee, Kyun Oh

2011-04-29

Proteomic analysis of a rice callus led to the identification of 10 abscisic acid (ABA)-induced proteins as putative products of the embryo-specific promoter candidates. 5'-flanking sequence of 1 Cys-Prx, a highly-induced protein gene, was cloned and analyzed. The transcription initiation site of 1 Cys-Prx maps 96 nucleotides upstream of the translation initiation codon and a TATA-box and putative seed-specific cis-acting elements, RYE and ABRE, are located 26, 115 and 124 bp upstream of the transcription site, respectively. β-glucuronidase (GUS) expression driven by the 1 Cys-Prx promoters was strong in the embryo and aleurone layer and the activity reached up to 24.9 ± 3.3 and 40.5 ± 2.1 pmol (4 MU/min/μg protein) in transgenic rice seeds and calluses, respectively. The activity of the 1 Cys-Prx promoters is much higher than that of the previously-identified embryo-specific promoters, and comparable to that of strong endosperm-specific promoters in rice. GUS expression driven by the 1 Cys-Prx promoters has been increased by ABA treatment and rapidly induced by wounding in callus and at the leaf of the transgenic plants, respectively. Furthermore, ectopic expression of the GUS construct in Arabidopsis suggested that the 1 Cys-Prx promoter also has strong activity in seeds of dicot plants. Copyright © 2011 Elsevier Inc. All rights reserved.

Radioisotopic 51Cr-leukocyte adherence inhibition (LAI) assay. I

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Tsang, P.H.; Tangnavarad, K.; Lesnick, G.; Holland, J.F.; Bekesi, J.G.; Perloff, M.

1980-01-01

A simplified radioisotopic leukocyte adherence inhibition assay ( 51 Cr-LAI assay) was used to determine tumor-directed immune responses in patients with cancer of the breast. Essential steps in development of this assay are the standardization of conditions for optimal 51 Cr uptake by peripheral blood lymphocytes (PBL) and the inclusion of autologous or normal AB serum in the incubation media. A dextrose salt mixture (GNK) was found to enhance intracellular uptake of 51 Cr significantly (8-fold) without affecting viability of the cells or without causing selective loss of lymphocyte subpopulations. The presence of 10% autologous or normal AB serum prevented non-specific LAI responses to unrelated tumor antigens. Experimental results are presented and it is seen that this short term (4 h) 51 Cr-LAI assay provides reproducible and specific results analogous to those using tube-LAI assay. The test has the advantages of being accurate, sensitive and free from technical bias. (Auth.)

Insulinoma imaging with glucagon-like peptide-1 receptor targeting probe (18)F-FBEM-Cys (39)-exendin-4.

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Xu, Yuping; Pan, Donghui; Xu, Qing; Zhu, Chen; Wang, Lizhen; Chen, Fei; Yang, Runlin; Luo, Shineng; Yang, Min

2014-09-01

Glucagon-like peptide-1 receptor (GLP-1R) is a specific target for insulinomas imaging since it is overexpressed in the tumor. Exendin-4 exhibits high affinity for the GLP-1R. In this study, a novel (18)F-labeled exendin-4 analog, (18)F-FBEM-Cys(39)-exendin-4, was synthesized and its potentials for GLP-1R imaging were also evaluated. (18)F-FBEM was synthesized by coupling (18)F-fluorobenzoic acid ((18)F-FBA) with N-(2-aminoethyl) maleimide, and the reaction conditions were optimized. Cys(39)-exendin-4 was then conjugated with (18)F-FBEM to obtain (18)F-FBEM-Cys(39)-exendin-4. The GLP-1R targeting potential and pharmacokinetic profile of the tracer were analyzed in INS-1 insulinoma and MDA-MB-435 breast tumor model, respectively. Under the optimal conditions, the yield of radiolabeled (18)F-FBEM was 49.1 ± 2.0 % (based on (18)F-FBA, non-decay corrected). The yield of (18)F-FBEM-Cys(39)-exendin-4 was 35.1 ± 2.6 % (based on the starting (18)F-FBEM, non-decay corrected). The radiochemical purity of (18)F-FBEM-Cys(39)-exendin-4 is >95 %, and the specific activity was at least 35 GBq/μmol. The GLP-1R-positive INS-1 insulinoma xenograft was clearly visible with good contrast to background, whereas GLP-1R-negative MDA-MB435 breast tumor was barely visible. Low levels of radioactivity were also detected at pancreas and lungs due to few GLP-1R expressions. GLP-1R binding specificity was demonstrated by reduced INS-1 tumor uptake of the tracer after coinjection with an excess of unlabeled Cys(39)-exendin-4 at 1 h postinjection. The thiol-reactive reagent, (18)F-FBEM, was prepared with high yield and successfully conjugated to Cys(39)-exendin-4. Favorable preclinical data showing specific and effective tumor targeting by (18)F-FBEM-Cys(39)-exendin-4 suggest that the tracer may be a potential probe for insulinomas imaging.

Synthesis of peptide templated copper nanoclusters for fluorometric determination of Fe(III) in human serum

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Tang, Ting; Ouyang, Jiang; Hu, Lanshuang; Guo, Linyan; Yang, Minghui; Chen, Xiang

2016-01-01

Copper nanoclusters (Cu-NCs) were prepared by reducing CuCl 2 with ascorbic acid in the presence of the short peptide template Cys-Cys-Cys-Asp-Leu. They were characterized by UV-vis absorption and fluorescence spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The Cu-NCs have a size of ∼2 nm, can be well dispersed in water and are photostable. Their fluorescence (peaking at 425 nm under 365-nm excitation) is quenched by Fe(III) ions. Based on this finding, a sensitive and selective fluorescence assay for the detection of Fe(III) was developed. Under optimized conditions and a pH value of 2.0, the assay displays a linear response in the 0.05 to 30 μM Fe(III) concentration range, with a detection limit of 20 nM based on an S/N ratio of 3. The assay was successfully applied to the determination of Fe(III) in spiked human serum where is gave recoveries that ranged from 96.2 % to 98.3 %. (author)

iSulf-Cys: Prediction of S-sulfenylation Sites in Proteins with Physicochemical Properties of Amino Acids.

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Xu, Yan; Ding, Jun; Wu, Ling-Yun

2016-01-01

Cysteine S-sulfenylation is an important post-translational modification (PTM) in proteins, and provides redox regulation of protein functions. Bioinformatics and structural analyses indicated that S-sulfenylation could impact many biological and functional categories and had distinct structural features. However, major limitations for identifying cysteine S-sulfenylation were expensive and low-throughout. In view of this situation, the establishment of a useful computational method and the development of an efficient predictor are highly desired. In this study, a predictor iSulf-Cys which incorporated 14 kinds of physicochemical properties of amino acids was proposed. With the 10-fold cross-validation, the value of area under the curve (AUC) was 0.7155 ± 0.0085, MCC 0.3122 ± 0.0144 on the training dataset for 20 times. iSulf-Cys also showed satisfying performance in the independent testing dataset with AUC 0.7343 and MCC 0.3315. Features which were constructed from physicochemical properties and position were carefully analyzed. Meanwhile, a user-friendly web-server for iSulf-Cys is accessible at http://app.aporc.org/iSulf-Cys/.

The 5-HT2C receptor gene Cys23Ser polymorphism influences the intravaginal ejaculation latency time in Dutch Caucasian men with lifelong premature ejaculation

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Paddy KC Janssen

2014-08-01

Full Text Available It has been postulated that the persistent short intravaginal ejaculation latency time (IELT of men with lifelong premature ejaculation (LPE is related to 5-hydroxytryptamine (HT2C receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2C receptor gene polymorphism and the duration of IELT in men with LPE. Therefore, a prospective study was conducted in 64 Dutch Caucasian men with LPE. Baseline IELT during coitus was assessed by stopwatch over a 1-month period. All men were genotyped for Cys23Ser 5-HT2C receptor gene polymorphism. Allele frequencies and genotypes of Cys and Ser variants of 5-HT2C receptor gene polymorphism were determined. Association between Cys/Cys and Ser/Ser genotypes and the natural logarithm of the IELT in men with LPE were investigated. As a result, the geometric mean, median and natural mean IELT were 25.2, 27.0, 33.9 s, respectively. Of all men, 20.0%, 10.8%, 23.1% and 41.5% ejaculated within 10, 10-20, 20-30 and 30-60 s after vaginal penetration. Of the 64 men, the Cys/Cys and Ser/Ser genotype frequency for the Cys23Ser polymorphism of the 5-HT2C receptor gene was 81% and 19%, respectively. The geometric mean IELT of the wildtypes (Cys/Cys is significantly lower (22.6 s; 95% CI 18.3-27.8 s than in male homozygous mutants (Ser/Ser (40.4 s; 95% CI 20.3-80.4 s (P = 0.03. It is concluded that Cys23Ser 5-HT2C receptor gene polymorphism is associated with the IELT in men with LPE. Men with Cys/Cys genotype have shorter IELTs than men with Ser/Ser genotypes.

The 5-HT2C receptor gene Cys23Ser polymorphism influences the intravaginal ejaculation latency time in Dutch Caucasian men with lifelong premature ejaculation.

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Janssen, Paddy Kc; Schaik, Ron van; Olivier, Berend; Waldinger, Marcel D

2014-01-01

It has been postulated that the persistent short intravaginal ejaculation latency time (IELT) of men with lifelong premature ejaculation (LPE) is related to 5-hydroxytryptamine (HT)2C receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2C receptor gene polymorphism and the duration of IELT in men with LPE. Therefore, a prospective study was conducted in 64 Dutch Caucasian men with LPE. Baseline IELT during coitus was assessed by stopwatch over a 1-month period. All men were genotyped for Cys23Ser 5-HT2C receptor gene polymorphism. Allele frequencies and genotypes of Cys and Ser variants of 5-HT2C receptor gene polymorphism were determined. Association between Cys/Cys and Ser/Ser genotypes and the natural logarithm of the IELT in men with LPE were investigated. As a result, the geometric mean, median and natural mean IELT were 25.2, 27.0, 33.9 s, respectively. Of all men, 20.0%, 10.8%, 23.1% and 41.5% ejaculated within 10, 10-20, 20-30 and 30-60 s after vaginal penetration. Of the 64 men, the Cys/Cys and Ser/Ser genotype frequency for the Cys23Ser polymorphism of the 5-HT2C receptor gene was 81% and 19%, respectively. The geometric mean IELT of the wildtypes (Cys/Cys) is significantly lower (22.6 s; 95% CI 18.3-27.8 s) than in male homozygous mutants (Ser/Ser) (40.4 s; 95% CI 20.3-80.4 s) (P = 0.03). It is concluded that Cys23Ser 5-HT2C receptor gene polymorphism is associated with the IELT in men with LPE. Men with Cys/Cys genotype have shorter IELTs than men with Ser/Ser genotypes.

Transient Transcriptional Regulation of the CYS-C1 Gene and Cyanide Accumulation upon Pathogen Infection in the Plant Immune Response1[C][W

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García, Irene; Rosas, Tábata; Bejarano, Eduardo R.; Gotor, Cecilia; Romero, Luis C.

2013-01-01

Cyanide is produced concomitantly with ethylene biosynthesis. Arabidopsis (Arabidopsis thaliana) detoxifies cyanide primarily through the enzyme β-cyanoalanine synthase, mainly by the mitochondrial CYS-C1. CYS-C1 loss of function is not toxic for the plant and leads to an increased level of cyanide in cys-c1 mutants as well as a root hairless phenotype. The classification of genes differentially expressed in cys-c1 and wild-type plants reveals that the high endogenous cyanide content of the cys-c1 mutant is correlated with the biotic stress response. Cyanide accumulation and CYS-C1 gene expression are negatively correlated during compatible and incompatible plant-bacteria interactions. In addition, cys-c1 plants present an increased susceptibility to the necrotrophic fungus Botrytis cinerea and an increased tolerance to the biotrophic Pseudomonas syringae pv tomato DC3000 bacterium and Beet curly top virus. The cys-c1 mutation produces a reduction in respiration rate in leaves, an accumulation of reactive oxygen species, and an induction of the alternative oxidase AOX1a and pathogenesis-related PR1 expression. We hypothesize that cyanide, which is transiently accumulated during avirulent bacterial infection and constitutively accumulated in the cys-c1 mutant, uncouples the respiratory electron chain dependent on the cytochrome c oxidase, and this uncoupling induces the alternative oxidase activity and the accumulation of reactive oxygen species, which act by stimulating the salicylic acid-dependent signaling pathway of the plant immune system. PMID:23784464

Higher Novel L-Cys Degradation Activity Results in Lower Organic-S and Biomass in Sarcocornia than the Related Saltwort, Salicornia.

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Kurmanbayeva, Assylay; Bekturova, Aizat; Srivastava, Sudhakar; Soltabayeva, Aigerim; Asatryan, Armine; Ventura, Yvonne; Khan, Mohammad Suhail; Salazar, Octavio; Fedoroff, Nina; Sagi, Moshe

2017-09-01

Salicornia and Sarcocornia are almost identical halophytes whose edible succulent shoots hold promise for commercial production in saline water. Enhanced sulfur nutrition may be beneficial to crops naturally grown on high sulfate. However, little is known about sulfate nutrition in halophytes. Here we show that Salicornia europaea (ecotype RN) exhibits a significant increase in biomass and organic-S accumulation in response to supplemental sulfate, whereas Sarcocornia fruticosa (ecotype VM) does not, instead exhibiting increased sulfate accumulation. We investigated the role of two pathways on organic-S and biomass accumulation in Salicornia and Sarcoconia : the sulfate reductive pathway that generates Cys and l-Cys desulfhydrase that degrades Cys to H 2 S, NH 3 , and pyruvate. The major function of O -acetyl-Ser-(thiol) lyase (OAS-TL; EC 2.5.1.47) is the formation of l-Cys, but our study shows that the OAS-TL A and OAS-TL B of both halophytes are enzymes that also degrade l-Cys to H 2 S. This activity was significantly higher in Sarcocornia than in Salicornia , especially upon sulfate supplementation. The activity of the sulfate reductive pathway key enzyme, adenosine 5'-phosphosulfate reductase (APR, EC 1.8.99.2), was significantly higher in Salicornia than in Sarcocornia These results suggest that the low organic-S level in Sarcocornia is the result of high l-Cys degradation rate by OAS-TLs, whereas the greater organic-S and biomass accumulation in Salicornia is the result of higher APR activity and low l-Cys degradation rate, resulting in higher net Cys biosynthesis. These results present an initial road map for halophyte growers to attain better growth rates and nutritional value of Salicornia and Sarcocornia . © 2017 American Society of Plant Biologists. All Rights Reserved.

The hOGG1 Ser326Cys polymorphism and prostate cancer risk: a meta-analysis of 2584 cases and 3234 controls

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Zhang Zhihong

2011-09-01

Full Text Available Abstract Background Genetic polymorphism of human 8-oxoguanine glycosylase 1 (hOGG1 Ser326Cys (rs1052133 has been implicated to alter the risk of prostate cancer, but the results are controversial. Methods Two investigators independently searched the Medline, and Cochrane Library up to June 7, 2011. Summary odds ratios (OR and 95% confidence interval (CI for Ser326Cys polymorphism and prostate cancer were calculated. Statistical analysis was performed with the software program Review Manage, version 5.0 and Stata 10.0. Results A total of 8 independent studies, including 2584 cases and 3234 controls, were identified. Our analysis suggested that Ser326Cys was not associated with prostate cancer risk in overall population. In the subgroup analysis, we detected the significant association between Ser326Cys polymorphism and decreased prostate risk in mixed population under additive model (OR = 0.67, 95% CI = 0.50-0.90, P = 0.007, recessive model (OR = 0.68, 95% CI = 0.51-0.91, P = 0.008, and Cys allele versus Ser allele (OR = 0.88, 95% CI = 0.78-0.98, P = 0.02. Subanalysis on Caucasian subjects demonstrated that Ser326Cys was not associated with prostate cancer risk. Conclusion This meta-analysis showed the evidence that hOGG1 Ser326Cys polymorphism was associated with a decreased risk of prostate cancer development in mixed populations.

The hOGG1 Ser326Cys Gene Polymorphism and the Risk of Coronary Ectasia in the Chinese Population

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Po-Chao Hsu

2014-01-01

Full Text Available Oxidative stress (OS is related to vascular inflammation possibly, contributing to the development of coronary ectasia (CE. Base excision repair (BER and nucleotide excision repair are the main DNA repair pathways that can help to remove 8-hydroxydeoxyguanine (8-OHdG, a marker of OS. Human 8-oxoguanine DNA glycosylase 1 (hOGG1 is a key enzyme of the BER pathway and catalyzes the removal of 8-OHdG. The aim of our study was to investigate the association between hOGG1 Ser326Cys gene polymorphism and CE in a Chinese population. Five-hundred forty-seven patients who underwent diagnostic coronary angiography in a tertiary medical center were recruited. The angiographic definition of CE is the diameter of the ectatic segment being more than 1.5 times larger compared with an adjacent healthy reference segment. The gene polymorphisms were analyzed by polymerase chain reaction. The urine 8OHdG concentration was measured using a commercial ELISA kit. The distribution of hOGG1 Ser326Cys genotypes was significantly different between CE and non-CE groups (p = 0.033. The odds ratio of CE development for the Ser to the Cys variant was 1.55 (95% confidence interval (CI, 1.04–2.31, p = 0.033. Both univariate and logistic regression analysis showed a significant association of hOGG1 Ser326Cys polymorphism in the dominant model with CE development (p = 0.009 and 0.011, respectively. Urine 8-OHdG levels were significantly higher in subjects carrying the hOGG1 Ser variant than in those with the Cys/Cys genotype (p < 0.03. In conclusion, our study suggests that the hOGG1 Ser326Cys gene variant might play a role in susceptibility to the development of CE.

Structural biology of the sequestration and transport of heavy metal toxins: NMR structure determination of proteins containing the -Cys-X-Y-Cys-metal binding motifs. 1997 annual progress report

International Nuclear Information System (INIS)

Opella, S.J.

1997-01-01

'There are enormous amounts of heavy metals in the environment, much of it in the form of organometallic compounds resulting from various types of industrial and military waste. Nearly all of these metals and compounds are highly toxic to biological organisms including humans. However, some bacteria thrive in the presence of high concentrations of heavy metal toxins because they possess efficient mechanisms for the detoxification of these metals and compounds. Heavy metals appear to be universally toxic because of their non-selective chemistry, for example Hg(II) reacts with essentially all exposed sulfhydryl groups on proteins, thus, it may seem surprising that any organism at all can survive these chemical insults much less those that grow in a toxic milieu. However, the prebiotic environment was undoubtedly heavily polluted with heavy metals from geological processes, and the most primitive organisms simply had to evolve mechanisms for dealing with them if they were going to be able to utilize Cys, His, and the other amino acids that contribute to metal binding sites in their proteins. Genes associated with bacterial resistance to Ag, AsO 2 , AsO 4 , Bi, Cd, Co, CrO 4 , Cu, Hg, iNi, TeO 3 , TI, Pb, Zn, and other metals of environmental concern have been described (Silver, 1992; Silver and Walderhaug, 1995).'

Feasibility of Biological Effective Monitoring of Chrome Electroplaters to Chromium through Analysis of Serum Malondialdehyde.

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Mozafari, P; Rezazadeh Azari, M; Shokoohi, Y; Sayadi, M

2016-10-01

Great concern about occupational exposure to chromium (Cr [VI]) has been reported due to escalated risk of lung cancer in exposed workers. Consequences of occupational exposure to Cr (VI) have been reported as oxidative stress and lung tissue damage. To investigate the feasibility of biological effect monitoring of chrome electroplaters through analysis of serum malondialdehyde (MDA). 90 workers directly involved in chrome electroplating---categorized into three equal groups based on their job as near bath workers, degreaser, and washers---and 30 workers without exposure to Cr (VI), served as the control group, were studied. Personal samples were collected and analyzed according to NIOSH method 7600. Serum MDA level was measured by HPLC using a UV detector. Median Cr (VI) exposure level was 0.38 mg/m(3) in near bath workers, 0.20 mg/m(3) in degreasers, and 0.05 mg/m(3) in washers. The median serum MDA level of three exposed groups (2.76 μmol/L) was significantly (p<0.001) higher than that in the control group (2.00 μmol/L). There was a positive correlation between electroplaters' level of exposure to Cr (VI) and their serum MDA level (Spearman's ρ 0.806, p<0.001). Serum MDA level is a good biomarker for the level of occupational exposure to Cr (VI) in electroplaters.

Feasibility of Biological Effective Monitoring of Chrome Electroplaters to Chromium through Analysis of Serum Malondialdehyde

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P Mozafari

2016-10-01

Full Text Available Background: Great concern about occupational exposure to chromium (Cr [VI] has been reported due to escalated risk of lung cancer in exposed workers. Consequences of occupational exposure to Cr (VI have been reported as oxidative stress and lung tissue damage. Objective: To investigate the feasibility of biological effect monitoring of chrome electroplaters through analysis of serum malondialdehyde (MDA. Methods: 90 workers directly involved in chrome electroplating—categorized into three equal groups based on their job as near bath workers, degreaser, and washers—and 30 workers without exposure to Cr (VI, served as the control group, were studied. Personal samples were collected and analyzed according to NIOSH method 7600. Serum MDA level was measured by HPLC using a UV detector. Results: Median Cr (VI exposure level was 0.38 mg/m3 in near bath workers, 0.20 mg/m3 in degreasers, and 0.05 mg/m3 in washers. The median serum MDA level of three exposed groups (2.76 μmol/L was significantly (p<0.001 higher than that in the control group (2.00 μmol/L. There was a positive correlation between electroplaters' level of exposure to Cr (VI and their serum MDA level (Spearman's ρ 0.806, p<0.001. Conclusion: Serum MDA level is a good biomarker for the level of occupational exposure to Cr (VI in electroplaters.

Early prediction of treatment response by serum CRP levels in patients with advanced esophageal cancer who underwent definitive chemoradiotherapy

International Nuclear Information System (INIS)

Yoneda, Masayuki; Fujiwara, Hitoshi; Okamura, Shinichi

2010-01-01

Serum C reactive protein (CRP) has been shown to be associated with the progression of esophageal cancer. The purpose of this study was to examine the relationship between treatment response and serum CRP levels in time course during definitive chemoradiotherapy (CRT) in terms of early prediction of CRT response by serum CRP. The subjects of this study were 36 patients with cT3/cT4 esophageal squamous cell carcinoma who underwent definitive CRT in our hospital. Serum CRP levels during definitive CRT (pretreatment, 1W, 2W and 3W after CRT initiation) were compared between CR and non-CR group. In addition, partition model was constructed to discriminate CR with non-CR and the prediction accuracy was evaluated. The patients were consisted of 28 males and 8 females. At pretreatment diagnosis, tumors were categorized as T3 (n=21) and T4 (n=15). Thirty four patients received FP-based chemotherapy and 2 patients received docetaxel-based chemotherapy. Treatment responses were categorized as CR (n=8), partial response (PR) (n=14), no change (NC) (n=2) and progressive disease (PD) (n=12). Serum CRP levels at the time of 2W after CRT initiation (CRT2W) in CR group were low compared to those in non-CR group (p=0.071). The partition model was constructed based on CRP levels at CRT2W. The prediction accuracies to discriminate CR from non-CR by CRP ≤0.1 were 50%, 82%, and 75% in sensitivity, specificity and accuracy, respectively. Serum CRP is a useful biomarker for an early prediction of CRT response. (author)

Mechanisms Underlying Early Rapid Increases in Creatinine in Paraquat Poisoning

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Mohamed, Fahim; Endre, Zoltan; Jayamanne, Shaluka; Pianta, Timothy; Peake, Philip; Palangasinghe, Chathura; Chathuranga, Umesh; Jayasekera, Kithsiri; Wunnapuk, Klintean; Shihana, Fathima; Shahmy, Seyed; Buckley, Nicholas

2015-01-01

Background Acute kidney injury (AKI) is common after severe paraquat poisoning and usually heralds a fatal outcome. The rapid large increases in serum creatinine (Cr) exceed that which can be explained by creatinine kinetics based on loss of glomerular filtration rate (GFR). Methods and Findings This prospective multi-centre study compared the kinetics of two surrogate markers of GFR, serum creatinine and serum cystatin C (CysC), following paraquat poisoning to understand and assess renal functional loss after paraquat poisoning. Sixty-six acute paraquat poisoning patients admitted to medical units of five hospitals were included. Relative changes in creatinine and CysC were monitored in serial blood and urine samples, and influences of non-renal factors were also studied. Results Forty-eight of 66 patients developed AKI (AKIN criteria), with 37 (56%) developing moderate to severe AKI (AKIN stage 2 or 3). The 37 patients showed rapid increases in creatinine of >100% within 24 hours, >200% within 48 hours and >300% by 72 hours and 17 of the 37 died. CysC concentration increased by 50% at 24 hours in the same 37 patients and then remained constant. The creatinine/CysC ratio increased 8 fold over 72 hours. There was a modest fall in urinary creatinine and serum/urine creatinine ratios and a moderate increase in urinary paraquat during first three days. Conclusion Loss of renal function contributes modestly to the large increases in creatinine following paraquat poisoning. The rapid rise in serum creatinine most probably represents increased production of creatine and creatinine to meet the energy demand following severe oxidative stress. Minor contributions include increased cyclisation of creatine to creatinine because of acidosis and competitive or non-competitive inhibition of creatinine secretion. Creatinine is not a good marker of renal functional loss after paraquat poisoning and renal injury should be evaluated using more specific biomarkers of renal injury

Cys-Ph-TAHA: a lanthanide binding tag for RDC and PCS enhanced protein NMR

International Nuclear Information System (INIS)

Peters, Fabian; Maestre-Martinez, Mitcheell; Leonov, Andrei; Kovačič, Lidija; Becker, Stefan; Boelens, Rolf; Griesinger, Christian

2011-01-01

Here we present Cys-Ph-TAHA, a new nonadentate lanthanide tag for the paramagnetic labelling of proteins. The tag can be easily synthesized and is stereochemically homogenous over a wide range of temperatures, yielding NMR spectra with a single set of peaks. Bound to ubiquitin, it induced large residual dipolar couplings and pseudocontact shifts that could be measured easily and agreed very well with the protein structure. We show that Cys-Ph-TAHA can be used to label large proteins that are biochemically challenging such as the Lac repressor in a 90 kDa ternary complex with DNA and inducer.

Value of serum TORCH-specific antibody detection in assessment of neonatal jaundice

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Guang-Hua Dai

2016-06-01

Full Text Available Objective: To study the value of serum TORCH-specific antibody detection in assessment of neonatal jaundice. Methods: A total of 70 cases of children with neonatal jaundice were selected as jaundice group, 70 cases of healthy newborn were the control group, and serum serum TORCH-specific antibody content as well as heart function, liver function, kidney function and nerve function indicators were detected. Results: Serum TOX-IgM, RV-IgM, CMV-IgM and HSV-IgM positive rate and content of jaundice group were significantly higher than those of control group; serum CK-MB, cTnI, AST, ALT, Cys-C, RBP, MBP, S100β and NSE content of TORCH-positive children were significantly higher than those of TORCHnegative children, and BDNF, NT-3, NT-4 and NGF content were significantly lower than those of TORCH-negative children; T1WI signal of pallidum MRI of TORCH-positive children was significantly higher than that of TORCH-negative children. Conclusions: Serum TORCHspecific antibodies significantly increase in children with neonatal jaundice and can assess the degree of bilirubin metabolism disorder and the degree of target organ damage.

Biochemical and functional analysis of two Plasmodium falciparum blood-stage 6-cys proteins: P12 and P41.

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Tana Taechalertpaisarn

Full Text Available The genomes of Plasmodium parasites that cause malaria in humans, other primates, birds, and rodents all encode multiple 6-cys proteins. Distinct 6-cys protein family members reside on the surface at each extracellular life cycle stage and those on the surface of liver infective and sexual stages have been shown to play important roles in hepatocyte growth and fertilization respectively. However, 6-cys proteins associated with the blood-stage forms of the parasite have no known function. Here we investigate the biochemical nature and function of two blood-stage 6-cys proteins in Plasmodium falciparum, the most pathogenic species to afflict humans. We show that native P12 and P41 form a stable heterodimer on the infective merozoite surface and are secreted following invasion, but could find no evidence that this complex mediates erythrocyte-receptor binding. That P12 and P41 do not appear to have a major role as adhesins to erythrocyte receptors was supported by the observation that antisera to these proteins did not substantially inhibit erythrocyte invasion. To investigate other functional roles for these proteins their genes were successfully disrupted in P. falciparum, however P12 and P41 knockout parasites grew at normal rates in vitro and displayed no other obvious phenotypic changes. It now appears likely that these blood-stage 6-cys proteins operate as a pair and play redundant roles either in erythrocyte invasion or in host-immune interactions.

Higher Novel L-Cys Degradation Activity Results in Lower Organic-S and Biomass in Sarcocornia than the Related Saltwort, Salicornia1[OPEN

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Kurmanbayeva, Assylay; Bekturova, Aizat; Soltabayeva, Aigerim; Asatryan, Armine; Ventura, Yvonne; Salazar, Octavio; Fedoroff, Nina

2017-01-01

Salicornia and Sarcocornia are almost identical halophytes whose edible succulent shoots hold promise for commercial production in saline water. Enhanced sulfur nutrition may be beneficial to crops naturally grown on high sulfate. However, little is known about sulfate nutrition in halophytes. Here we show that Salicornia europaea (ecotype RN) exhibits a significant increase in biomass and organic-S accumulation in response to supplemental sulfate, whereas Sarcocornia fruticosa (ecotype VM) does not, instead exhibiting increased sulfate accumulation. We investigated the role of two pathways on organic-S and biomass accumulation in Salicornia and Sarcoconia: the sulfate reductive pathway that generates Cys and l-Cys desulfhydrase that degrades Cys to H2S, NH3, and pyruvate. The major function of O-acetyl-Ser-(thiol) lyase (OAS-TL; EC 2.5.1.47) is the formation of l-Cys, but our study shows that the OAS-TL A and OAS-TL B of both halophytes are enzymes that also degrade l-Cys to H2S. This activity was significantly higher in Sarcocornia than in Salicornia, especially upon sulfate supplementation. The activity of the sulfate reductive pathway key enzyme, adenosine 5′-phosphosulfate reductase (APR, EC 1.8.99.2), was significantly higher in Salicornia than in Sarcocornia. These results suggest that the low organic-S level in Sarcocornia is the result of high l-Cys degradation rate by OAS-TLs, whereas the greater organic-S and biomass accumulation in Salicornia is the result of higher APR activity and low l-Cys degradation rate, resulting in higher net Cys biosynthesis. These results present an initial road map for halophyte growers to attain better growth rates and nutritional value of Salicornia and Sarcocornia. PMID:28743765

Effect of Intravenous Administration of Contrast Media on Serum Creatinine Levels in Neonates.

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Bedoya, Maria A; White, Ammie M; Edgar, J Christopher; Pradhan, Madhura; Raab, Elisabeth L; Meyer, James S

2017-08-01

Purpose To assess the effect of intravenous contrast media on renal function in neonates. Materials and Methods Institutional review board approval was obtained with waiver of consent. Electronic health records from January 2011 to April 2013 were reviewed retrospectively. Measures of renal function were obtained in inpatient neonates who underwent magnetic resonance (MR) imaging or computed tomography (CT) and for whom serum creatinine (Cr) levels were obtained within 72 hours before imaging and at least one time after imaging (>1 day after administration of contrast material). A total of 140 neonates who received contrast material (59 who underwent CT with iohexol or iodixanol and 81 who underwent MR imaging with gadopentetate dimeglumine) were identified. These neonates were frequency matched according to sex, gestational and postnatal age, and preimaging serum Cr levels with neonates who underwent unenhanced MR imaging or CT. Cr levels and glomerular filtration rates (GFRs) were grouped according to when they were obtained (before imaging, 1-2 days after imaging, 3-5 days after imaging, 6-9 days after imaging, 10-45 days after imaging, and more than 45 days after imaging). Serum Cr levels and GFRs for each time period were compared between groups by using hierarchic regressions or χ 2 or Fisher exact tests and with repeated-measures analysis of variance to compare groups on the rate of change in serum Cr levels and GFRs from before to after imaging. Results Cr levels decreased and GFRs increased in both groups from before to after imaging (CT group, P ≤ .01; MR imaging group, P ≤ .01). The neonates who underwent contrast material-enhanced imaging and the neonates who underwent unenhanced imaging showed similar serum Cr levels at all examined time periods. Groups also did not differ in the proportion of neonates with serum Cr levels higher than the reference range (>0.4 mg/dL) at any time point (iodine- [P > .12] or gadolinium-based [P > .13] contrast

The Activity of TcCYS4 Modified by Variations in pH and Temperature Can Affect Symptoms of Witches’ Broom Disease of Cocoa, Caused by the Fungus Moniliophthora perniciosa

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Freitas, Ana Camila Oliveira; Souza, Cristiane Ferreira; Monzani, Paulo Sérgio; Garcia, Wanius; de Almeida, Alex Alan Furtado; Costa, Marcio Gilberto Cardoso; Pirovani, Carlos Priminho

2015-01-01

The phytocystatins regulate various physiological processes in plants, including responses to biotic and abiotic stresses, mainly because they act as inhibitors of cysteine proteases. In this study, we have analyzed four cystatins from Theobroma cacao L. previously identified in ESTs libraries of the interaction with the fungus Moniliophthora perniciosa and named TcCYS1, TcCYS2, TcCYS3 and TcCYS4. The recombinant cystatins were purified and subjected to the heat treatment, at different temperatures, and their thermostabilities were monitored using their ability to inhibit papain protease. TcCYS1 was sensitive to temperatures above 50°C, while TcCYS2, TcCYS3, and TcCYS4 were thermostable. TcCYS4 presented a decrease of inhibitory activity when it was treated at temperatures between 60 and 70°C, with the greater decrease occurring at 65°C. Analyses by native gel electrophoresis and size-exclusion chromatography showed that TcCYS4 forms oligomers at temperatures between 60 and 70°C, condition where reduction of inhibitory activity was observed. TcCYS4 oligomers remain stable for up to 20 days after heat treatment and are undone after treatment at 80°C. TcCYS4 presented approximately 90% of inhibitory activity at pH values between 5 and 9. This protein treated at temperatures above 45°C and pH 5 presented reduced inhibitory activity against papain, suggesting that the pH 5 enhances the formation of TcCYS4 oligomers. A variation in the titratable acidity was observed in tissues of T. cacao during the symptoms of witches’ broom disease. Our findings suggest that the oligomerization of TcCYS4, favored by variations in pH, is an endergonic process. We speculate that this process can be involved in the development of the symptoms of witches’ broom disease in cocoa. PMID:25830226

Lymphocyte cytotoxicity induced by preincubation with serum from patients with Hashimoto thyroiditis

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Calder, Elizabeth A.; McLeman, Dena; Irvine, W. J.

1973-01-01

Lymphocytes from healthy donors were incubated with serum samples from nine patients with Hashimoto thyroiditis and subsequently shown to be cytotoxic to chicken red blood cells (Ch. RBC) coated with thyroglobulin. Target cell death was estimated using a standard 51Cr release assay system. Lymphocytes pre-incubated with Hashimoto serum caused a mean% 51Cr release of 13·11±2·83 (SEM) from thyroglobulin-coated Ch. RBC and a mean% 51Cr release of 1·22±0·65 from uncoated Ch. RBC. Untreated lymphocytes caused no significant isotope release from either uncoated or thyroglobulin coated target cells. PMID:4800956

Human erythrocytes inhibit complement-mediated solubilization of immune complexes by human serum

International Nuclear Information System (INIS)

Dorval, B.L.

1987-01-01

The aim of this study was to develop an autologus human system to evaluate the effects of human erythrocytes on solubilization of immune complex precipitates (IC) by human serum. Incubation of IC with fresh human serum or guinea pig serum resulted in solubilization of IC. When packed erythrocytes were added to human serum or guinea pig serum binding of IC to the erythrocyte occurred and IC solubilization was inhibited significantly (p <.025). Sheep erythrocytes did not bind IC or inhibit IC solubilization. To evaluate the role of human erythrocyte complement receptor (CR1) on these findings, human erythrocytes were treated with trypsin or anti-CR1 antibodies. Both treatments abrogated IC binding to human erythrocytes but did not affect the ability of the human erythrocyte to inhibit IC solubilization. Radioimmunoassay was used to measure C3, C4 and C5 activation in human serum after incubation with IC, human erythrocytes, human erythrocytes plus IC, whole blood or in whole blood plus IC

Role of an Absolutely Conserved Tryptophan Pair in the Extracellular Domain of Cys-Loop Receptors

DEFF Research Database (Denmark)

Braun, Nina; Lynagh, Timothy; Yu, Rilei

2016-01-01

Cys-loop receptors mediate fast synaptic transmission in the nervous system, and their dysfunction is associated with a number of diseases. While some sequence variability is essential to ensure specific recognition of a chemically diverse set of ligands, other parts of the underlying amino acid...... sequences show a high degree of conservation, possibly to preserve the overall structural fold across the protein family. In this study, we focus on the only two absolutely conserved residues across the Cys-loop receptor family, two Trp side chains in the WXD motif of Loop D and in the WXPD motif of Loop A...

Mapping the pulmonary environment of animals protected from virulent H1N1 influenza infection using the TLR-2 agonist Pam₂Cys.

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Mifsud, Edin J; Tan, Amabel C L; Reading, Patrick C; Jackson, David C

2016-02-01

We have previously shown that intranasal administration of the Toll-like receptor-2 agonist, S-(2,3-bis(palmitoyloxy)propyl) cysteine (Pam2Cys), provides immediate and antigen independent protection against challenge with influenza virus. Here we characterize the cellular pulmonary environments of mice which had either been treated with Pam2Cys or placebo and then challenged with influenza virus. We show that Pam2Cys treatment results in the influx of innate immune cells into the lungs and that depletion of phagocytic cells from this influx using clodronate-loaded liposomes caused a reduction in the number of interstitial macrophages and monocytes. This resulted in abolition of the protective effect indicating the importance of this cellular subset in Pam2Cys-mediated protection.

A functional Ser326Cys polymorphism in hOGG1 is associated with noise-induced hearing loss in a Chinese population.

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Huanxi Shen

Full Text Available DNA damage to cochlear hair cells caused by 8-oxoguanine (8-oxoG is essential for the development of noise-induced hearing loss (NIHL. Human 8-oxoG DNA glycosylase1 (hOGG1 is a key enzyme in the base excision repair (BER pathway that eliminates 8-oxoG. Many epidemiological and functional studies have suggested that the hOGG1 Ser326Cys polymorphism (rs1052133 is associated with many diseases. The purpose of this investigation was to investigate whether the hOGG1 Ser326Cys polymorphism in the human BER pathway is associated with genetic susceptibility to NIHL in a Chinese population. This polymorphism was genotyped among 612 workers with NIHL and 615 workers with normal hearing. We found that individuals with the hOGG1 Cys/Cys genotype had a statistically significantly increased risk of NIHL compared with those who carried the hOGG1 Ser/Ser genotype (adjusted OR=1.59, 95% CI=1.13-2.25 and this increased risk was more pronounced among the workers in the 15- to 25- and >25-year noise exposure time, 85-92 dB(A noise exposure level, ever smoking, and ever drinking groups, similar effects were also observed in a recessive model. In summary, our data suggested that the hOGG1 Cys/Cys genotype may be a genetic susceptibility marker for NIHL in the Chinese Han population.

Ultrasound assessment of mitral annular displacement in patients with coronary heart disease and its correlation with left heart function and serum indexes

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Bing-Yan Lai

2016-10-01

Full Text Available Objective: To analyze the ultrasound assessment of mitral annular displacement in patients with coronary heart disease and its correlation with left heart function and serum indexes. Methods: A total of 89 patients with coronary heart disease were divided into angina pectoris group 42 cases and myocardial infarction group 47 cases according to the illness, and 58 cases of healthy subjects were included in control group. Values of mitral annular displacement (MAD parameters, left heart function indexes and serum illness-related indexes of three groups were detected, and the correlation between values of MAD parameters and values of cardiac function indexes and serum illness-related indexes were further analyzed. Results: MAD parameters TMAD1, TMAD2 and TMADmid values, heart function LVEF values and serum CysC level of myocardial infarction group and angina pectoris group were lower than those of control group, and cardiac function LVEDD, LVESD and A/E values as well as serum H-FABP, ICTP, Hcy and vWF levels were higher than those of control group (P<0.05; MAD parameters TMAD1, TMAD2 and TMADmid values of patients with coronary heart disease were negatively correlated with LVEDD, LVESD and A/E values as well as H-FABP, ICTP, Hcy and vWF levels, and were positively correlated with LVEF value and CysC level (P<0.05. Conclusions: Ultrasound assessment of mitral annular displacement in patients with coronary heart disease can early diagnose coronary heart disease and judge the disease severity, and it plays a positive role in optimizing disease prognosis.

Chromium and cobalt ion concentrations in blood and serum following various types of metal-on-metal hip arthroplasties

DEFF Research Database (Denmark)

Jantzen, Christopher; Jørgensen, Henrik L; Duus, Benn R

2013-01-01

Widely different metal ion concentrations in blood and serum have been reported with metal-on-metal (MoM) implants. We reviewed the literature on blood and serum ion concentrations of chromium (Cr) and cobalt (Co) following various MoM hip arthroplasties.......Widely different metal ion concentrations in blood and serum have been reported with metal-on-metal (MoM) implants. We reviewed the literature on blood and serum ion concentrations of chromium (Cr) and cobalt (Co) following various MoM hip arthroplasties....

Changes in selected serum parameters of broiler chicken fed supplemental chromium.

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Króliczewska, B; Zawadzki, W; Dobrzanski, Z; Kaczmarek-Oliwa, A

2004-12-01

The present study was conducted to evaluate the effect of chromium (Cr) from Cr yeast on the growth performance and total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglycerides, glucose, total protein and Cr concentration in the serum of broiler chicken. The birds were fed a control diet or a control diet supplemented with Cr at a level of 300, 500 microg/kg Cr. The supplementation of 500 mug/kg Cr increased body weight, weight gain and feed efficiency (p broiler chicken and can be used as additives in animal diet but it still needs more investigations.

Lung Cancer Susceptibility and hOGG1 Ser326Cys Polymorphism: A Meta-Analysis

International Nuclear Information System (INIS)

Kiyohara, Chikako; Takayama, Koichi; Nakanishi, Yoichi

2010-01-01

Recent lung cancer studies have focused on identifying the effects of single nucleotide polymorphisms (SNPs) in candidate genes, among which DNA repair genes are increasingly being studied. Genetic variations in DNA repair genes are thought to modulate DNA repair capacity and are suggested to be related to lung cancer risk. In this study, we tried to assess reported studies of association between polymorphism of human 8-oxoguanine DNA glycosylase 1 (hOGG1) Ser326Cys and lung cancer. We conducted MEDLINE, Current Contents and Web of Science searches using 'hOGG1', 'lung cancer' and 'polymorphism' as keywords to search for papers published (from January 1995 through August 2010). Data were combined using both a fixed effects (the inverse variance-weighted method) and a random effects (DerSimonian and Laird method) models. The Cochran Q test was used for the assessment of heterogeneity. Publication bias was assessed by both Begg’s and Egger’s tests. We identified 20 case-control studies in 21 different ethnic populations. As two studies were not in the Hardy-Weinberg equilibrium, 18 case-control studies in 19 different ethnic populations (7,792 cases and 9,358 controls) were included in our meta-analysis. Summary frequencies of the Cys allele among Caucasians and Asians based on the random effects model were 20.9% (95% confidence interval (CI) = 18.9–22.9) and 46.1% (95% CI = 40.2–52.0), respectively. The distribution of the Cys allele was significantly different between Asians and Caucasians (P < 0.001). The Cys/Cys genotype was significantly associated with lung cancer risk in Asian populations (odds ratio = 1.27, 95% CI = 1.09–1.48) but not in Caucasian populations. This ethnic difference in lung cancer risk may be due to environmental factors such as cigarette smoking and dietary factors. Although the summary risk for developing lung cancer may not be large, lung cancer is such a common malignancy that even a small increase

Lung Cancer Susceptibility and hOGG1 Ser326Cys Polymorphism: A Meta-Analysis

Energy Technology Data Exchange (ETDEWEB)

Kiyohara, Chikako, E-mail: chikako@phealth.med.kyushu-u.ac.jp [Department of Preventive Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Takayama, Koichi; Nakanishi, Yoichi [Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)

2010-10-28

Recent lung cancer studies have focused on identifying the effects of single nucleotide polymorphisms (SNPs) in candidate genes, among which DNA repair genes are increasingly being studied. Genetic variations in DNA repair genes are thought to modulate DNA repair capacity and are suggested to be related to lung cancer risk. In this study, we tried to assess reported studies of association between polymorphism of human 8-oxoguanine DNA glycosylase 1 (hOGG1) Ser326Cys and lung cancer. We conducted MEDLINE, Current Contents and Web of Science searches using 'hOGG1', 'lung cancer' and 'polymorphism' as keywords to search for papers published (from January 1995 through August 2010). Data were combined using both a fixed effects (the inverse variance-weighted method) and a random effects (DerSimonian and Laird method) models. The Cochran Q test was used for the assessment of heterogeneity. Publication bias was assessed by both Begg’s and Egger’s tests. We identified 20 case-control studies in 21 different ethnic populations. As two studies were not in the Hardy-Weinberg equilibrium, 18 case-control studies in 19 different ethnic populations (7,792 cases and 9,358 controls) were included in our meta-analysis. Summary frequencies of the Cys allele among Caucasians and Asians based on the random effects model were 20.9% (95% confidence interval (CI) = 18.9–22.9) and 46.1% (95% CI = 40.2–52.0), respectively. The distribution of the Cys allele was significantly different between Asians and Caucasians (P < 0.001). The Cys/Cys genotype was significantly associated with lung cancer risk in Asian populations (odds ratio = 1.27, 95% CI = 1.09–1.48) but not in Caucasian populations. This ethnic difference in lung cancer risk may be due to environmental factors such as cigarette smoking and dietary factors. Although the summary risk for developing lung cancer may not be large, lung cancer is such a common malignancy that even a small increase

Relationship between intestinal permeability to [51Cr]EDTA and inflammatory activity in asymptomatic patients with Crohn's disease

International Nuclear Information System (INIS)

Pironi, L.; Miglioli, M.; Ruggeri, E.; Levorato, M.; Dallasta, M.A.; Corbelli, C.; Nibali, M.G.; Barbara, L.

1990-01-01

The relationship between intestinal permeability to an oral dose (100 mu Ci) of [51CR]EDTA and the inflammatory activity of Crohn's disease was studied in 63 adult patients (32 unresected and 31 resected) who underwent 162 evaluations. The results of the [51CR]EDTA test were compared with the serum levels of the acute-phase reactant proteins (APRP) and with the result of the [111In]leukocyte scanning, respectively, as an indirect and direct method to assess intestinal inflammation. In a group of healthy adult controls, the upper normal value for the 24-hr urinary [51CR]EDTA excretion was 3.61 (97.5% percentile) and the mean coefficient of variation was 21%. Sensitivity and specificity of the [51CR]EDTA test in identifying active inflammation expressed by increased serum levels of APRP were, respectively, 97% and 54% in the unresected group and 68% and 52% in the resected group of patients. The low specificity of the test was due to the presence of increased [51CR]EDTA urinary excretion in about half the cases with normal serum levels of APRP. The [111In]leukocyte scanning was performed in a subgroup of 11 patients (three unresected and eight resected) with normal serum levels of APRP, six with increased and five with normal [51CR]EDTA urinary excretion. All six patients with increased intestinal permeability had a positive 111In image of mild to moderate degree of activity. A positive 111In scan was present in two of the five patients with normal permeability; these were two resected patients

In vitro cellular adaptations of indicators of longevity in response to treatment with serum collected from humans on calorie restricted diets.

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Joanne S Allard

2008-09-01

Full Text Available Calorie restriction (CR produces several health benefits and increases lifespan in many species. Studies suggest that alternate-day fasting (ADF and exercise can also provide these benefits. Whether CR results in lifespan extension in humans is not known and a direct investigation is not feasible. However, phenotypes observed in CR animals when compared to ad libitum fed (AL animals, including increased stress resistance and changes in protein expression, can be simulated in cells cultured with media supplemented with blood serum from CR and AL animals. Two pilot studies were undertaken to examine the effects of ADF and CR on indicators of health and longevity in humans. In this study, we used sera collected from those studies to culture human hepatoma cells and assessed the effects on growth, stress resistance and gene expression. Cells cultured in serum collected at the end of the dieting period were compared to cells cultured in serum collected at baseline (before the dieting period. Cells cultured in serum from ADF participants, showed a 20% increase in Sirt1 protein which correlated with reduced triglyceride levels. ADF serum also induced a 9% decrease in proliferation and a 25% increase in heat resistance. Cells cultured in serum from CR participants induced an increase in Sirt1 protein levels by 17% and a 30% increase in PGC-1alpha mRNA levels. This first in vitro study utilizing human serum to examine effects on markers of health and longevity in cultured cells resulted in increased stress resistance and an up-regulation of genes proposed to be indicators of increased longevity. The use of this in vitro technique may be helpful for predicting the potential of CR, ADF and other dietary manipulations to affect markers of longevity in humans.

Effects of Supplemental Chromium Source and Concentration on Growth, Carcass Characteristics, and Serum Lipid Parameters of Broilers Reared Under Normal Conditions.

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Zheng, Cancai; Huang, Yanling; Xiao, Fang; Lin, Xi; Lloyd, Karen

2016-02-01

An experiment was conducted to investigate the effects of dietary chromium (Cr) source and concentration on growth performance, carcass traits, and some serum lipid parameters of broilers under normal rearing conditions for 42 days. A total of 252 1-day-old Cobb 500 commercial female broilers were randomly allotted by body weight (BW) to one of six replicate cages (six broilers per cage) for each of seven treatments in a completely randomized design involved in a 2 × 3 factorial arrangement of treatments with three Cr sources (Cr propionate (CrPro), Cr picolinate (CrPic), Cr chloride (CrCl3)) and two concentrations of added Cr (0.4 and 2.0 mg of Cr/kg) plus a Cr-unsupplemented control diet. The results showed that dietary Cr supplementation tended to increase the breast muscle percentage compared with the Cr-unsupplemented control group (P = 0.0784), while Cr from CrPic tended to have higher breast muscle percentage compared with Cr from CrCl3 (P = 0.0881). Chromium from CrPic also tended to increase the breast intramuscular fat (IMF) compared with Cr from CrCl3 (P = 0.0648). In addition, supplementation of 0.4 mg/kg Cr tended to decrease low-density lipoprotein cholesterol (LDL-C) (P = 0.0614). Compared with the control group, broilers fed Cr-supplemented diets had higher triglyceride (TG) (P = 0.0129) regardless of Cr source and Cr concentration. Chromium from CrPro and CrPic had lower total cholesterol (TC) compared with Cr from CrCl3 (P = 0.0220). These results indicate that dietary supplementation of Cr has effects on carcass characteristics and serum lipid parameters of broilers under normal rearing conditions, while supplementation of organic Cr can improve carcass characteristics and reduce the cholesterol content in serum.

Leukotriene D4 induces chemotaxis in human eosinophilc cell line, EoL-1 cells via CysLT1 receptor activation.

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Shirasaki, Hideaki; Kanaizumi, Etsuko; Himi, Tetsuo

2017-11-01

Numerous reports have shown that cysteinyl leukotrienes (CysLTs) contribute to tissue accumulation of eosinophils in allergic airway inflammation. To date, only a few studies have reported that CysLTs promote chemotactic activity of human eosinophils in vitro. The purpose of this study was to investigate whether CysLTs promote chemotaxis in the human eosinophilic cell line, EoL-1. EoL-1 cells were induced to differentiate into mature eosinophil-like cells via incubation with butyric acid and cytokines (IL-3, IL-5 and GM-CSF). The chemotactic activity of the differentiated EoL-1 cells was assessed using the commercial cell migration assay kit. LTD 4 elicited dose-related chemotactic activity in the differntiated EoL-1 cells in the range of 1-100 nM. A typical bell-shaped dose-response curve was observed with optimal activity at 10 nM. The chemotactic activity elicited by LTD 4 (10 nM) was significantly inhibited by montelukast (control, 345 ± 19.2 × 10 3 RFU; LTD 4 10 nM alone, 511 ± 39.2 × 10 3 RFU; LTD 4 10 nM plus montelukast 100 nM, 387 ± 28.2 × 10 3 RFU). LTD 4 induces migration in eosinophilic cells via activation of CysLT1 receptor. The present in vitro model may be useful for elucidation of the mechanism underlying CysLT-induced tissue eosinophilia.

The electrostatic role of the Zn-Cys2His2 complex in binding of operator DNA with transcription factors: mouse EGR-1 from the Cys2His2 family.

Science.gov (United States)

Chirgadze, Y N; Boshkova, E A; Polozov, R V; Sivozhelezov, V S; Dzyabchenko, A V; Kuzminsky, M B; Stepanenko, V A; Ivanov, V V

2018-01-07

The mouse factor Zif268, known also as early growth response protein EGR-1, is a classical representative for the Cys2His2 transcription factor family. It is required for binding the RNA polymerase with operator dsDNA to initialize the transcription process. We have shown that only in this family of total six Zn-finger protein families the Zn complex plays a significant role in the protein-DNA binding. Electrostatic feature of this complex in the binding of factor Zif268 from Mus musculus with operator DNA has been considered. The factor consists of three similar Zn-finger units which bind with triplets of coding DNA. Essential contacts of the factor with the DNA phosphates are formed by three conservative His residues, one in each finger. We describe here the results of calculations of the electrostatic potentials for the Zn-Cys2His2 complex, Zn-finger unit 1, and the whole transcription factor. The potential of Zif268 has a positive area on the factor surface, and it corresponds exactly to the binding sites of each of Zn-finger units. The main part of these areas is determined by conservative His residues, which form contacts with the DNA phosphate groups. Our result shows that the electrostatic positive potential of this histidine residue is enhanced due to the Zn complex. The other contacts of the Zn-finger with DNA are related to nucleotide bases, and they are responsible for the sequence-specific binding with DNA. This result may be extended to all other members of the Cys2His2 transcription factor family.

Protein-stabilized fluorescent nanocrystals consisting of a gold core and a silver shell for detecting the total amount of cysteine and homocysteine

International Nuclear Information System (INIS)

Gui, Rijun; Wang, Yanfeng; Sun, Jie

2014-01-01

We report on a simple and sensitive method for the determination of the total amount of cysteine (Cys) and homocysteine (hCys), [Cys plus hCys], by exploiting the effect of Cys and hCys on the photoluminescence of human serum albumin-stabilized gold-core silver-shell nanocrystals (NCs). If Cys (or hCys) are added to these NCs, Cys (or hCys) will be adsorbed on the surface due to ligand exchange with human serum albumin, and this results in the quenching of the luminescence of the NCs. The addition of mixtures of Cys and hCys in different molar ratios also induces a decrease in luminescence whose intensity is linearly related to the concentration of [Cys plus hCys] in the range from 0.1 – 5.0 μM, with a correlation coefficient (R 2 ) of 0.9953 and a detection limit of 15 nM. The method is highly selective and sensitive over other α-amino acids, water-soluble thiols, and biomolecules. It has been successfully applied to the determination of the concentration of [Cys plus hCys] in spiked solutions of biomolecules and in real biological samples (author)

Comparison of cystatin C- and creatinine-based estimated glomerular filtration rate to predict coronary heart disease risk in Japanese patients with obesity and diabetes.

Science.gov (United States)

Ito, Ryo; Yamakage, Hajime; Kotani, Kazuhiko; Wada, Hiromichi; Otani, Sumire; Yonezawa, Kazuya; Ogo, Atsushi; Okajima, Taiichiro; Adachi, Masahiro; Araki, Rika; Yoshida, Kazuro; Saito, Miho; Nagaoka, Tadasu; Toyonaga, Tetsushi; Tanaka, Tsuyoshi; Yamada, Tsutomu; Ota, Itsuro; Oishi, Mariko; Miyanaga, Fumiko; Shimatsu, Akira; Satoh-Asahara, Noriko

2015-01-01

The aim of this study is to determine which indicator of chronic kidney disease most closely correlates with 10-year Framingham coronary heart disease (CHD) risk among serum creatinine, serum cystatin C (S-CysC), urine albumin-creatinine ratio (UACR), estimated creatinine-based GFRs (eGFRcre), and estimated CysC-based GFRs (eGFRcys) in patients with obesity and diabetes. Serum creatinine, S-CysC, UACR, and cardio-ankle vascular index (CAVI) were examined in 468 outpatients with obesity and type 2 diabetes, free of severe renal dysfunction or previous history of cardiovascular disease, as a cross-sectional survey using baseline data from the multi-centered Japan Diabetes and Obesity Study. S-CysC and eGFRcys had significantly stronger correlations with the 10-year Framingham CHD risk than serum creatinine, eGFRcre, and UACR (creatinine, ρ = 0.318; S-CysC, ρ = 0.497; UACR, ρ = 0.174; eGFRcre, ρ = -0.291; eGFRcys, ρ = -0.521; P obesity and diabetes.

The Ser311Cys variation in the paraoxonase 2 gene increases the ...

Indian Academy of Sciences (India)

Supplementary data: The Ser311Cys variation in the paraoxonase 2 gene increases the risk of type 2 diabetes in northern Chinese. Yanchun Qu, Ze Yang, Feng Jin, Liang Sun, Chuanfang Zhang, Linong Ji, Hong Sun, Binyou Wang and Li Wang. J. Genet. 87, 165–169. Table 1. Clinical characteristics of case and control.

Positive Impact of Nutritional Interventions on Serum Symmetric Dimethylarginine and Creatinine Concentrations in Client-Owned Geriatric Cats.

Directory of Open Access Journals (Sweden)

Jean A Hall

Full Text Available A prospective study was conducted in client-owned geriatric cats to evaluate the short- term effects of a test food on serum symmetric dimethylarginine (SDMA and creatinine (Cr concentrations. Test food contained functional lipids (fish oil, antioxidants (vitamins C and E, L-carnitine, botanicals (vegetables, highly bioavailable protein, and amino acid supplements. Cats (n = 80 were fed either test food or owner's-choice foods (non-nutritionally controlled cohort. Cats were included based on age (≥ 9 years, indoor only, neutered, and free of chronic disease. At baseline, all cats had serum Cr concentrations within the reference interval. Renal function biomarkers and urinalysis results at baseline and after consuming test food or owner's-choice foods for 3 and 6 months were evaluated. Cats consuming test food showed significant decreases in serum Cr and BUN concentrations across time. Overall, cats consuming owner's-choice foods showed significant increases in serum SDMA concentrations at 3 and 6 months compared with baseline (P ≤ 0.05, whereas in cats consuming test food serum SDMA concentrations did not change. At baseline or during the 6-month feeding trial, 23 (28.8% cats had increased serum SDMA, but normal serum Cr consistent with IRIS Stage 1 chronic kidney disease. This included 6 cats fed test food and 17 cats fed owner's-choice foods. In the 6 cats fed test food, serum SDMA decreased in 3 cats and remained stable in 1 cat, whereas in the 17 cats fed owner's-choice foods, serum SDMA increased in 13 cats and decreased or remained stable in 4 cats. The increase in serum SDMA concentration was significant (P = 0.02 only for cats fed owner's-choice foods. These results suggest that nonazotemic cats with elevated serum SDMA (early renal insufficiency when fed a food designed to promote healthy aging are more likely to demonstrate stable renal function compared with cats fed owner's-choice foods. Cats fed owner's-choice foods were more

Serum creatinine and creatinine clearance for predicting plasma methotrexate concentrations after high-dose methotrexate chemotherapy for the treatment for childhood lymphoblastic malignancies.

Science.gov (United States)

Xu, Wei-qun; Zhang, Ling-yan; Chen, Xue-ying; Pan, Bin-hua; Mao, Jun-qing; Song, Hua; Li, Jing-yuang; Tang, Yong-min

2014-01-01

Monitoring of plasma methotrexate (MTX) concentrations allows for therapeutic adjustments in treating childhood acute lymphoblastic leukemia (ALL) or non-Hodgkin lymphoma (NHL) with high-dose MTX (HDMTX). We tested the hypothesis that assessment of creatinine clearance (CrCl) and/or serum Cr may be a suitable means of monitoring plasma MTX concentrations. All children in the study had ALL or NHL, were in complete remission, and received HDMTX (3 or 5 g/m(2))+leucovorin. Plasma MTX concentrations were measured at 24, 48, and 96 h. CrCl was determined at 24 and 48 h. Correlations between 24- and 48-h plasma MTX concentrations and CrCl and serum Cr concentrations were determined. CrCl and serum Cr concentrations were compared over time between children who had delayed and non-delayed MTX elimination. A total of 105 children were included. There were significant negative correlations between CrCl at 24 and 48 h and plasma MTX concentrations at 24 (both p < 0.001) and 48 h (both p < 0.001). There were significant positive correlations between serum Cr concentrations at both 24 and 48 h and plasma MTX concentrations at 24 (both p < 0.001) and 48 h (both p < 0.001). There were 88 (30.2 %) instances of elimination delay. Children with elimination delay had significantly lower CrCl and higher Cr concentrations at 24 and 48 h compared with children without elimination delay (all p < 0.05). Our findings suggest that, with further refinement, assessment of renal function may be a useful means of monitoring plasma MTX concentrations during HDMTX for ALL and NHL.

Extension arm facilitated pegylation of alphaalpha-hemoglobin with modifications targeted exclusively to amino groups: functional and structural advantages of free Cys-93(beta) in the PEG-Hb adduct.

Science.gov (United States)

Li, Dongxia; Hu, Tao; Manjula, Belur N; Acharya, Seetharama A

2009-11-01

Cys-93(beta) of hemoglobin (Hb) was reversibly protected as a mixed disulfide with thiopyridine during extension arm facilitated (EAF) PEGylation and its influence on the structural and functional properties of the EAF-PEG-Hb has been investigated. Avoiding PEGylation of Cys-93(beta) in the EAF-PEG-Hb lowers the level of perturbation of heme pocket, alpha1beta2 interface, autoxidation, heme loss, and the O(2) affinity, as compared to the EAF-PEG-Hb with PEGylation of Cys-93(beta).The structural and functional advantages of reversible protection of Cys-93(beta) during EAF PEGylation of oxy-Hb has been compared with Euro PEG-Hb generated by EAF PEGylation of deoxy Hb where Cys-93(beta) is free in the final product. The alphaalpha-fumaryl cross-linking and EAF PEGylation targeted exclusively to Lys residues has been combined together for generation of second-generation EAF-PEG-Hb with lower oxygen affinity. The PEG chains engineered on Lys as well as PEGylation of Cys-93(beta) independently contribute to the stabilization of oxy conformation of Hb and hence increase the oxygen affinity of Hb. However, oxygen affinity of the EAF-PEG-alphaalpha-Hb is more sensitive to the presence of PEGylation on Cys-93(beta) than that of the EAF-PEG-Hb. The present modified EAF PEGylation platform is expected to facilitate the design of novel versions of the EAF-PEG-Hbs that can now integrate the advantages of avoiding PEGylation of Cys-93(beta).

Unraveling the mechanism responsible for the contrasting tolerance of Synechocystis and Synechococcus to Cr(VI): Enzymatic and non-enzymatic antioxidants

Energy Technology Data Exchange (ETDEWEB)

Gupta, Alka [Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Ballal, Anand, E-mail: aballal@barc.gov.in [Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 40085 (India)

2015-07-15

Highlights: • Cr(VI) accumulation generates higher ROS in Synechocystis than in Synechococcus. • Synechococcus exhibits better photosynthetic activity in response to Cr(VI). • Synechococcus has higher enzymatic/non-enzymatic antioxidants than Synechocystis. • Synechococcus shows better tolerance to other oxidative stresses than Synechocystis. • Differential detoxification of ROS is responsible for the contrasting tolerance to Cr(VI) - Abstract: Two unicellular cyanobacteria, Synechocystis and Synechococcus, showed contrasting tolerance to Cr(VI); with Synechococcus being 12-fold more tolerant than Synechocystis to potassium dichromate. The mechanism responsible for this differential sensitivity to Cr(VI) was explored in this study. Total content of photosynthetic pigments as well as photosynthetic activity decreased at lower concentration of Cr(VI) in Synechocystis as compared to Synechococcus. Experiments with {sup 51}Cr showed Cr to accumulate intracellularly in both the cyanobacteria. At lower concentrations, Cr(VI) caused excessive ROS generation in Synechocystis as compared to that observed in Synechococcus. Intrinsic levels of enzymatic antioxidants, i.e., superoxide dismutase, catalase and 2-Cys-peroxiredoxin were considerably higher in Synechococcus than Synechocystis. Content of total thiols (both protein as well as non-protein) and reduced glutathione (GSH) was also higher in Synechococcus as compared to Synechocystis. This correlated well with higher content of carbonylated proteins observed in Synechocystis than Synechococcus. Additionally, in contrast to Synechocystis, Synechococcus exhibited better tolerance to other oxidative stresses like high intensity light and H{sub 2}O{sub 2}. The data indicate that the disparity in the ability to detoxify ROS could be the primary mechanism responsible for the differential tolerance of these cyanobacteria to Cr(VI)

Involvement of the Cys-Tyr cofactor on iron binding in the active site of human cysteine dioxygenase.

Science.gov (United States)

Arjune, Sita; Schwarz, Guenter; Belaidi, Abdel A

2015-01-01

Sulfur metabolism has gained increasing medical interest over the last years. In particular, cysteine dioxygenase (CDO) has been recognized as a potential marker in oncology due to its altered gene expression in various cancer types. Human CDO is a non-heme iron-dependent enzyme, which catalyzes the irreversible oxidation of cysteine to cysteine sulfinic acid, which is further metabolized to taurine or pyruvate and sulfate. Several studies have reported a unique post-translational modification of human CDO consisting of a cross-link between cysteine 93 and tyrosine 157 (Cys-Tyr), which increases catalytic efficiency in a substrate-dependent manner. However, the reaction mechanism by which the Cys-Tyr cofactor increases catalytic efficiency remains unclear. In this study, steady-state kinetics were determined for wild type CDO and two different variants being either impaired or saturated with the Cys-Tyr cofactor. Cofactor formation in CDO resulted in an approximately fivefold increase in k cat and tenfold increase in k cat/K m over the cofactor-free CDO variant. Furthermore, iron titration experiments revealed an 18-fold decrease in K d of iron upon cross-link formation. This finding suggests a structural role of the Cys-Tyr cofactor in coordinating the ferrous iron in the active site of CDO in accordance with the previously postulated reaction mechanism of human CDO. Finally, we identified product-based inhibition and α-ketoglutarate and glutarate as CDO inhibitors using a simplified well plate-based activity assay. This assay can be used for high-throughput identification of additional inhibitors, which may contribute to understand the functional importance of CDO in sulfur amino acid metabolism and related diseases.

Diagnostic value of cystatin C for diagnosis of early renal damages in type 2 diabetic mellitus patients: The first experience in Iran

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Mitra Javanmardi

2015-01-01

Full Text Available Background: Diabetic nephropathy (DN is one of the most important complications of diabetes mellitus. Now-a-days, cystatin C (CysC is introduced as a new marker for diagnosis of renal damages; however, use of this marker in clinical laboratories is still controversial. The present study was aimed to evaluate the diagnostic value of serum CysC for early detection or monitoring treatment of kidney damages in the Kurdish people with type 2 diabetes mellitus. Materials and Methods: Glomerular filtration rate (GFR was estimated by Modification of Diet in Renal Disease formula. Serum CysC and urine microalbumin were also measured in 126 diabetic and healthy subjects. Blood glycated hemoglobin (Hb also measured in all healthy and diabetic patients. Two independent samples t-test, Mann-Whitney U-test, one-way ANOVA, and Kruskal-Wallis test, as well as Pearson/Spearman correlation coefficient statistical tests were used as appropriate. Results: Serum CysC was higher (1312.41 ng/ml in diabetic patients with GFR <60 ml/min than other subjects (993.25 ng/ml (patients with normal kidney function and healthy subjects. A borderline significant correlation between CysC and estimating GFR (rs = −0.16, P = 0.05 but highly significant with microalbumin (rs = 0.22, P = 0.014 was observed. Serum CysC sensitivity, negative and positive predictive values were 100 and 4%. Conclusion: CysC cover variation of GFR and urine microalbumin, but it cannot be used as a surrogating marker of glycated Hb. According to our results, it seems that serum CysC is a useful marker for screening of DN; but it cannot be used for monitoring of treatment in diabetic patients.

Correlation study on cystatin C and ischemic stroke

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CHEN Rong-bo

2013-06-01

Full Text Available Objective To investigate the relationship between serum cystatin C (Cys C and patients with acute ischemic stroke. Methods The clinical and laboratory data of 115 patients with acute ischemic stroke and 110 controls were recorded and analyzed. Results The serum Cys C levels of patients in ischemic stroke group [(1.15 ± 0.34 mg/L] were higher than that of the control group [(0.99 ± 0.25 mg/L]. The difference between two groups was significant after correction of age and cardiovascular risk factors (t = ? 3.889, P = 0.000. It was found that age, Cys C, homocysteine (Hcy, type 2 diabetes mellitus [hemoglobin A1c (HbA1c, fructosamine (FRU], smoking, alcohol consumption, hypertension and intima-media thickness (IMT were risk factors for ischemic stroke on univariate Logistic regression analysis. The difference of serum Cys C level between the patients and controls was significant (P = 0.000, but through covariance analysis, after adjusted other risk factors, it was not significant (P = 0.875. Conclusion The serum Cys C levels of patients in ischemic stroke group is higher than the control group. It can be used as an indicator in the acute phase of ischemic stroke. The elevation of serum Cys C is a risk factor for ischemic stroke, but not an independent risk factor.

The use of CR1aa for ovine in vitro embryo production

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Yulnawati

2006-06-01

Full Text Available The aim of this study was to investigate the capacity of CR1aa as a simple medium for maturation, fertilization and culture of ovine embryo in vitro. Oocytes were collected by slicing method in Phosphate Buffer Saline (PBS supplemented with 5% Fetal Bovine Serum (FBS and 100 IU/ml penicillin streptomycin. Oocytes were matured in Tissue Culture Medium (TCM-199 as control or CR1aa as treatment medium. Both maturation medium were supplemented with 10% Fetal Bovine Serum (FBS, 10 IU/ml Follicle Stimulating Hormone (FSH, 10 IU/ml Luteinizing Hormone (LH, 1 μg/ml Estradiol and 100 IU/ml penicillin-streptomycin. Oocytes were incubated in 5% CO2 incubator, 38˚C for 24 h. Matured oocytes were fertilized in BO or CR1aa medium, supplemented with 2.5 mM caffeine benzoate and 20 mg /ml heparin. After 18 h in vitro fertilization, oocytes were cultured in TCM-199 or CR1aa medium, both supplemented with 5% FBS, 5 mg/ml insulin and 100 IU/ml penicillin streptomycin. Results showed that the highest maturation rate was found in TCM-199 medium (73.27% and significantly different (P0.05 between cleavage rate of ovine embryos in TCM-199 and CR1aa medium (39.45% vs 50.94%. In conclusion, optimum result on ovine in vitro embryo production can be achieved from a combination of TCM-199 as maturation medium and CR1aa as fertilization and culture medium.

A New Serum Biomarker for Lung Cancer - Transthyretin

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Liyun LIU

2009-04-01

Full Text Available Background and objective Lung cancer is the leading cause of cancer death worldwide and very few specific biomarkers could be used in clinical diagnosis at present. The aim of this study is to find novel potential serum biomarkers for lung cancer using Surface Enhanced Laser Desorption/Ionization (SELDI technique. Methods Serumsample of 227 cases including 146 lung cancer, 13 pneumonia, 28 tuberculous pleurisy and 40 normal individuals were analyzed by CM10 chips. The candidate biomarkers were identified by ESI/MS-MS and database searching, and further confirmed by immunoprecipitation. The same sets of serum sample from all groups were re-measured by ELISA assay. Results Three protein peaks with the molecular weight 13.78 kDa, 13.90 kDa and 14.07 kDa were found significantlydecreased in lung cancer serum compared to the other groups and were all automatically selected as specific biomarkers by Biomarker Wizard software. The candidate biomarkers obtained from 1-D SDS gel bands by matching the molecular weight with peaks on CM10 chips were identified by Mass spectrometry as the native transthyretin (nativeTTR, cysTTR and glutTTR, and the identity was further validated by immunoprecipitation using commercial TTR antibodies. Downregulated of TTR was found in both ELISA and SELDI analysis. Conclusion TTRs acted as the potentially useful biomarkers for lung cancer by SELDI technique.

Photodynamically generated bovine serum albumin radicals

DEFF Research Database (Denmark)

Silvester, J A; Timmins, G S; Davies, Michael Jonathan

1998-01-01

Porphyrin-sensitized photoxidation of bovine serum albumin (BSA) results in oxidation of the protein at (at least) two different, specific sites: the Cys-34 residue giving rise to a thiyl radical (RS.); and one or both of the tryptophan residues (Trp-134 and Trp-214) resulting in the formation...... of tertiary carbon-centred radicals and disruption of the tryptophan ring system. In the case of porphyrins such as hematoporphyrin, which bind at specific sites on BSA, these species appear to arise via long-range transfer of damage within the protein structure, as the binding site is some distance from...... the ultimate site of radical formation. This transfer of damage is shown to depend on a number of factors including the conformation of the protein, the presence of blocking groups and pH. Alteration of the protein conformation results in radical formation at additional (or alternative) sites, as does blocking...

Coevolution of the Ile1,016 and Cys1,534 Mutations in the Voltage Gated Sodium Channel Gene of Aedes aegypti in Mexico.

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Farah Z Vera-Maloof

2015-12-01

Full Text Available Worldwide the mosquito Aedes aegypti (L. is the principal urban vector of dengue viruses. Currently 2.5 billion people are at risk for infection and reduction of Ae. aegypti populations is the most effective means to reduce the risk of transmission. Pyrethroids are used extensively for adult mosquito control, especially during dengue outbreaks. Pyrethroids promote activation and prolong the activation of the voltage gated sodium channel protein (VGSC by interacting with two distinct pyrethroid receptor sites [1], formed by the interfaces of the transmembrane helix subunit 6 (S6 of domains II and III. Mutations of S6 in domains II and III synergize so that double mutants have higher pyrethroid resistance than mutants in either domain alone. Computer models predict an allosteric interaction between mutations in the two domains. In Ae. aegypti, a Ile1,016 mutation in the S6 of domain II was discovered in 2006 and found to be associated with pyrethroid resistance in field populations in Mexico. In 2010 a second mutation, Cys1,534 in the S6 of domain III was discovered and also found to be associated with pyrethroid resistance and correlated with the frequency of Ile1,016.A linkage disequilibrium analysis was performed on Ile1,016 and Cys1,534 in Ae. aegypti collected in Mexico from 2000-2012 to test for statistical associations between S6 in domains II and III in natural populations. We estimated the frequency of the four dilocus haplotypes in 1,016 and 1,534: Val1,016/Phe1,534 (susceptible, Val1,016/Cys1,534, Ile1,016/Phe1,534, and Ile1,016/Cys1,534 (resistant. The susceptible Val1,016/Phe1,534 haplotype went from near fixation to extinction and the resistant Ile1,016/Cys1,534 haplotype increased in all collections from a frequency close to zero to frequencies ranging from 0.5-0.9. The Val1,016/Cys1,534 haplotype increased in all collections until 2008 after which it began to decline as Ile1,016/Cys1,534 increased. However, the Ile1,016/Phe1

Association of serum lipoprotein (a) with hypertension in diabetic patients

International Nuclear Information System (INIS)

Nasri, H.

2008-01-01

To evaluate the influence of serum Lp(a) concentration on hypertension in patients with diabetes mellitus (DM) and under treatment with oral hypoglycemic agents or insulin injections, we studied 122 patients, 82 females and 40 males with a mean age of 63+-10 years and duration of DM and HTN of 7.4+-5.8 and 3.2+-4.6 years, respectively. The mean systolic and diastolic blood pressure (BP) was 138+-23 mmHg and 83+-12mmHg, respectively. In this cross-sectional study, we measured serum lipoprotein (a) (Lp(a), glycosilated hemoglobin (HbA1c) and other lipids while the patients were receiving either oral hypoglycemic agents or insulin. In addition, body mass index (BMI) and creatinine clearance (CrCL) were assessed. The mean serum Lp(a) was 22.2+-24.7 mg/dl (median: 18.3 mg/dl), and serum Lp(a) levels >30 mg/dl was found in 29(23.8%) patients. There were significant positive correlations of duration of DM and duration of hypertension, and serum Lp(a) levels with of systoli and diastolic levels of BP. However, a significant inverse correlation of serum Lp(a) with CrCl were observed. This study suggests that kidney function is an independent determination of Lp(a) and HTN in diabetic patients. Furthermore Lp(a) in diabetic patients may have important implications for the increased susceptibility to vascular diseases in these patients. (author)

Association of Serum Lipoprotein (a with Hypertension in Diabetic Patients

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Nasri Hamid

2008-01-01

Full Text Available To evaluate the influence of serum Lp(a concentration on hypertension in patients with diabetes mellitus (DM and under treatment with oral hypoglycemic agents or insulin injections, we studied 122 patients, 82 females and 40 males with a mean age of 63 ± 10 years and duration of DM and HTN of 7.4 ± 5.8 and 3.2 ± 4.6 years, respectively. The mean systolic and diastolic blood pressure (BP were 138 ±23 mmHg and 83 ± 12 mmHg, respectively. In this cross-sectional study, we measured serum lipoprotein(a (Lp(a, glycosilated hemoglobine (HbA1c and other lipids while the patients were receiving either oral hypogycemic agents or insulin. In addition, body mass index (BMI and creatinine clearance (CrCL were asessed. The mean serum Lp(a was 22.2 ± 24.7 mg/dl (median: 18.3 mg/dl, and serum Lp(a levels > 30 mg/dl was found in 29 (23.8% patients. There were significant positive correlations of duration of DM and duration of hypertension, and serum Lp(a levels with of systoli and diastolic levels of BP. However, a significant inverse correlation of serum Lp(a with CrCL were observed. This study suggests that kidney function is an independent determinant of Lp(a and HTN in diabetic patients. Furthermore, Lp(a in diabetic patients may have important implications for the increased susceptibility to vascular disease in these patients.

The elements Se, Hg, Cr, Sb, Fe, Zn, Co, and Rb were investigated by neutron activation analysis in blood serum of leukemia patients and workers of metal coating industries

International Nuclear Information System (INIS)

Taheriean, Ali Akbar.

1992-02-01

Current universal interests in trace element studies are being spurred by our needs to determine trace element requirements and tolerance by organism, including relationships to animal and human health and disease, evaluate the potential bio magnification and bio toxicity of trace elements. The element Se, Hg, Cr, Sb, Fe, Zn, Co, and Rb were investigated in blood serum of 24 leukemia patients and 20 workers of metal coating of industries, using neutron activation analysis and gamma ray counting high purity germanium detector, it was possible to determine the above mentioned trace elements with great accuracy. The result of these investigations are described briefly. In the blood serum of leukemia patients, which were collected from Ali Asghar children Hospital, some increase of Fe and decrease of Se could be found, whereas the amount variation of other trace elements were negligible. The amount of Zn in the blood serum of these workers by comparison with 60 normal man indicates no change. Due to importance of trace elements in the human health we suggest that this investigation must be prolonged using more samples

Effects of physical exercise training in DNA damage and repair - could the difference be in hOGG1 Ser326Cys polymorphism?

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Ana Inês Silva

2015-05-01

The aim of this study was to investigate the possible influence of hOGG1 Ser326Cys polymorphism on DNA damage and repair activity in response to 16 weeks of combined physical exercise training, in thirty healthy Caucasian men. Comet assay was carried out using peripheral blood lymphocytes and enabled the evaluation of DNA damage, both strand breaks and FPG-sensitive sites, and DNA repair activity. Genotypes were determined by PCR-RFLP analysis. The subjects with Ser/Ser genotype were considered as wild-type group (n=20, Ser/Cys and Cys/Cys genotype were analyzed together as mutant group (n=10. Regarding differences between pre and post-training in the wild-type group, the results showed a significant decrease in DNA strand breaks (DNA SBs (p=0.002 and also in FPG-sensitive sites (p=0.017. No significant differences were observed in weight (p=0.389 and in lipid peroxidation (MDA (p=0.102. A significant increase in total antioxidant capacity (evaluated by ABTS was observed (p=0.010. Regarding mutant group, the results showed a significant decrease in DNA SBs (p=0.008 and in weight (p=0.028. No significant differences were observed in FPG-sensitive sites (p=0.916, in ABTS (p=0.074 and in MDA (p=0.086. No significant changes in DNA repair activity were observed in both genotype groups. This preliminary study suggests the possibility of different responses in DNA damage to physical exercise training, considering the hOGG1 Ser326Cys polymorphism.

A Dutch kindred with familial amyloidotic polyneuropathy associated with the transthyretin Cys 114 mutant

NARCIS (Netherlands)

Haagsma, EB; Post, JG; DeJager, AEJ; Nikkels, PGJ; Hamel, BCJ; Hazenberg, BPC

A Dutch kindred with transthyretin Cys 114 related familial amyloidotic polyneuropathy is reported. The finding of early involvement of the heart is of great concern and of special relevance to the optimal timing for liver transplantation. To date, the variant had only been reported to be present in

Cys-Ph-TAHA: a lanthanide binding tag for RDC and PCS enhanced protein NMR

NARCIS (Netherlands)

Peters, Fabian; Maestre-Martinez, M.; Leonov, A.; Kovacic, L.; Becker, S.; Boelens, R.; Griesinger, C.

2011-01-01

Here we present Cys-Ph-TAHA, a new nonadentate lanthanide tag for the paramagnetic labelling of proteins. The tag can be easily synthesized and is stereochemically homogenous over a wide range of temperatures, yielding NMR spectra with a single set of peaks. Bound to ubiquitin, it induced large

Study of serum copper and ceruloplasmin levels in Egyptian autistic ...

African Journals Online (AJOL)

Farida El-Baz

2018-02-15

Feb 15, 2018 ... examination, IQ assessment, estimation of serum copper and ceruloplasmin levels. Results: A statistically ... April 2012. The control group ... Mental age рMAЮ assessed using the proper test ..... In: Reynolds CR, Kamphaus.

The sequential action of a dipeptidase and a beta-lyase is required for the release of the human body odorant 3-methyl-3-sulfanylhexan-1-ol from a secreted Cys-Gly-(S) conjugate by Corynebacteria.

Science.gov (United States)

Emter, Roger; Natsch, Andreas

2008-07-25

Human axillary odor is formed by the action of Corynebacteria on odorless axilla secretions. Sulfanylalkanols, 3-methyl-3-sulfanylhexan-1-ol in particular, form one key class of the odoriferous compounds. A conjugate with the dipeptide Cys-Gly has been reported as the secreted precursor for 3-methyl-3-sulfanylhexan-1-ol. Here, we confirm the Cys-Gly-(S) conjugate as the major precursor of this odorant, with lower levels of the Cys-(S) conjugate being present in axilla secretions. The enzymatic release of 3-methyl-3-sulfanylhexan-1-ol from the Cys-Gly-(S) conjugate by the axilla isolate Corynebacterium Ax20 was thus investigated. Cellular extracts of Ax20 released 3-methyl-3-sulfanylhexan-1-ol from the Cys-Gly-(S) conjugate and from the Cys-(S) conjugate, whereas the previously isolated C-S lyase of this bacterial strain was only able to cleave the Cys-(S) conjugate. o-Phenanthroline blocked the release from the Cys-Gly-(S) conjugate but did not affect cleavage of the Cys-(S) conjugate, indicating that in a first step, a metal-dependent dipeptidase hydrolyzes the Cys-Gly bond. This enzyme was purified by four chromatographic steps and gel electrophoresis, and the partial amino acid sequence was determined. The corresponding gene was cloned and expressed in Escherichia coli. It codes for a novel dipeptidase with a high affinity toward the Cys-Gly-(S) conjugate of 3-methyl-3-sulfanylhexan-1-ol. Co-incubating either the synthetic Cys-Gly-(S) conjugate or fresh axilla secretions with both the C-S lyase and the novel dipeptidase did release 3-methyl-3-sulfanylhexan-1-ol, proving that the sequential action of these two enzymes from the skin bacterium Corynebacterium Ax20 does release the odorant from the key secreted precursor.

Lead inhibition of DNA-binding mechanism of Cys(2)His(2) zinc finger proteins.

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Hanas, J S; Rodgers, J S; Bantle, J A; Cheng, Y G

1999-11-01

The association of lead with chromatin in cells suggests that deleterious metal effects may in part be mediated through alterations in gene function. To elucidate if and how lead may alter DNA binding of cysteine-rich zinc finger proteins, lead ions were analyzed for their ability to alter the DNA binding mechanism of the Cys(2)His(2) zinc finger protein transcription factor IIIA (TFIIIA). As assayed by DNase I protection, the interaction of TFIIIA with the 50-bp internal control region of the 5S ribosomal gene was partially inhibited by 5 microM lead ions and completely inhibited by 10 to 20 microM lead ions. Preincubation of free TFIIIA with lead resulted in DNA-binding inhibition, whereas preincubation of a TFIIIA/5S RNA complex with lead did not result in DNA-binding inhibition. Because 5S RNA binds TFIIIA zinc fingers, this result is consistent with an inhibition mechanism via lead binding to zinc fingers. The complete loss of DNase I protection on the 5S gene indicates the mechanism of inhibition minimally involves the N-terminal fingers of TFIIIA. Inhibition was not readily reversible and occurred in the presence of an excess of beta-mercaptoethanol. Inhibition kinetics were fast, progressing to completion in approximately 5 min. Millimolar concentrations of sulfhydryl-specific arsenic ions were not inhibitory for TFIIIA binding. Micromolar concentrations of lead inhibited DNA binding by Sp1, another Cys(2)His(2) finger protein, but not by the nonfinger protein AP2. Inhibition of Cys(2)His(2) zinc finger transcription factors by lead ions at concentrations near those known to have deleterious physiological effects points to new molecular mechanisms for lead toxicity in promoting disease.

Selenocysteine vs Cysteine: Tuning the Derivatization on Benzenesulfonyl Moiety of a Triazole Linked Dansyl Connected Glycoconjugate for Selective Recognition of Selenocysteine and the Applicability of the Conjugate in Buffer, in Serum, on Silica Gel, and in HepG2 Cells.

Science.gov (United States)

Areti, Sivaiah; Verma, Surendra Kumar; Bellare, Jayesh; Rao, Chebrolu Pulla

2016-07-19

A dansyl derivatized triazole linked glucopyranosyl conjugate ((NO2)L) has been synthesized and characterized and was used in the present study. The conjugate (NO2)L releases a fluorescent product upon reaction by Cys-SeH in aqueous PBS buffer by exhibiting a ∼210-fold fluorescence enhancement even in the presence of 20 other amino acids with a minimum detection limit of (1.5 ± 0.2) × 10(-7) M. The selectivity of the Cys-SeH to (NO2)L was further proven by extending the fluorescence study to different other selenium compounds. The role of para-nitrobenzenesulfonyl (pNBS) center in (NO2)L in the selective recognition of Cys-SeH was confirmed when the fluorescence emission studies were carried out using five different derivatizations possessing two NO2, five fluoro, two fluoro, one fluoro, and no fluoro groups. The nucleophilic substitution reaction of Cys-SeH on (NO2)L has been clearly demonstrated on the basis of (1)H NMR, ESI-MS, and absorption spectroscopy, and the heat changes were monitored by isothermal titration calorimetry. The application potential of (NO2)L has been demonstrated by studying its selectivity toward Cys-SeH in aqueous PBS buffer, in bovine serum, and on the silica gel surface that lead to minimum detection limits of (25 ± 2), (80 ± 5), and (168 ± 16) ppb, respectively. The biological applicability of (NO2)L for Cys-SeH was further demonstrated in HepG2 cells by fluorescence microscopy. Thus, (NO2)L is aqueous soluble and a biologically acceptable probe for Cys-SeH.

Proton induced X-ray emission analysis of trace elements in human blood serum

International Nuclear Information System (INIS)

Cheek, D.B.; Hay, H.J.; Newton, C.S.

1979-01-01

Proton induced x-ray emission has been used for quantitative analyses of trace elements in blood serum samples. This work is part of a survey concerned with Zn, Cu, Fe, Cr, Mn and Se in Australian Aboriginal people not receiving optimal diet. Special attention is being directed to Cr because of the high incidence of diabetes mellitus in these people

Simultaneous enrichment of cysteine-containing peptides and phosphopeptides using a cysteine-specific phosphonate adaptable tag (CysPAT) in combination with titanium dioxide (TiO2) chromatography

DEFF Research Database (Denmark)

Huang, Honggang; Pedersen, Martin Haar; Ibañez-Vea, Maria

2016-01-01

to selectively label cysteine-containing peptides (Cys peptides) followed by their enrichment with titanium dioxide (TiO2) and subsequent mass spectrometric analysis. The CysPAT strategy was developed using a synthetic peptide, a standard protein and subsequently the strategy was applied to protein lysates from...

A near-infrared luminescent Mn2+-doped NaYF4:Yb,Tm/Fe3+ upconversion nanoparticles redox reaction system for the detection of GSH/Cys/AA.

Science.gov (United States)

Zhang, Liping; Ling, Bo; Wang, Lun; Chen, Hongqi

2017-09-01

An upconversion luminescence method was developed for the determination of glutathione (GSH), L-cysteine (Cys) or L-ascorbic acid (AA) based on redox reaction. We synthesized poly(acrylic acid) (PAA)-modified Mn 2+ -doped NaYF 4 :Yb,Tm upconversion nanoparticles (UCNPs), and the luminescence of these UCNPs was effectively quenched due to their carboxyl groups coordinating with Fe 3+ to form a UCNPs/Fe 3+ system. GSH, Cys or AA reduced Fe 3+ to Fe 2+ , which induced the luminescence recovery of the UCNPs. Under the optimized conditions, wide linear concentration ranges from 0.25-300μM for GSH, 0.5-875μM for Cys and 0.5-350μM for AA were found, and the detection limits (3S/K) were 0.2μM, 0.5μM and 0.2μM, respectively. Thus, the UCNPs/Fe 3+ system was successfully applied for sensing GSH, Cys or AA. Copyright © 2017 Elsevier B.V. All rights reserved.

Age-dependent oxidation of extracellular cysteine/cystine redox state (Eh(Cys/CySS)) in mouse lung fibroblasts is mediated by a decline in Slc7a11 expression.

Science.gov (United States)

Zheng, Yuxuan; Ritzenthaler, Jeffrey D; Burke, Tom J; Otero, Javier; Roman, Jesse; Watson, Walter H

2018-04-01

Aging is associated with progressive oxidation of the extracellular environment. The redox state of human plasma, defined by the concentrations of cysteine (Cys) and cystine (CySS), becomes more oxidized as we age. Recently, we showed that fibroblasts isolated from the lungs of young and old mice retain this differential phenotype; old cells produce and maintain a more oxidizing extracellular redox potential (E h (Cys/CySS)) than young cells. Microarray analysis identified down-regulation of Slc7a11, the light subunit of the CySS/glutamate transporter, as a potential mediator of age-related oxidation in these cells. The purpose of the present study was to investigate the mechanistic link between Slc7a11 expression and extracellular E h (Cys/CySS). Sulforaphane treatment or overexpression of Slc7a11 was used to increase Slc7a11 in lung fibroblasts from old mice, and sulfasalazine treatment or siRNA-mediated knock down was used to decrease Slc7a11 in young fibroblasts. Slc7a11 mRNA levels were measured by real-time PCR, Slc7a11 activity was determined by measuring the rate of glutamate release, Cys, CySS, glutathione (GSH) and its disulfide (GSSG) were measured by HPLC, and E h (Cys/CySS) was calculated from the Nernst equation. The results showed that both E h (Cys/CySS) and E h (GSH/GSSG) were more oxidized in the conditioned media of old cells than in young cells. Up-regulation of Slc7a11 via overexpression or sulforaphane treatment restored extracellular E h (Cys/CySS) in cultures of old cells, whereas down-regulation reproduced the oxidizing E h (Cys/CySS) in young cells. Only sulforaphane treatment was able to increase total GSH and restore E h (GSH/GSSG), whereas overexpression, knock down and sulfasalazine had no effect on these parameters. In addition, inhibition of GSH synthesis with buthionine sulfoximine had no effect on the ability of cells to restore their extracellular redox potential in response to an oxidative challenge. In conclusion, our study

Expression, purification and preliminary crystallographic analysis of Mycobacterium tuberculosis CysQ, a phosphatase involved in sulfur metabolism

Energy Technology Data Exchange (ETDEWEB)

Erickson, Anna I.; Sarsam, Reta D.; Fisher, Andrew J., E-mail: ajfisher@ucdavis.edu

2014-05-10

The cysQ gene from Mycobacterium tuberculosis was cloned and the expressed protein, a 3′-phosphoadenosine-5′’-phosphatase, was purified and crystallized. X-ray diffraction data were collected to 1.7 Å resolution.

Correlating blood levels of 8-hydroxydeoxyguanosine to hOGG1 genotypes and the incidence of ischemic cardiomyopathy

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Yu Jin

2016-05-01

Full Text Available We measured the serum levels of 8-hydroxydeoxyguanosine (8-OHdG and investigated whether these levels correlate with incidence of ischemic cardiomyopathy (ICM, and whether these levels correlate with underlying oxidative stress in patients with ICM. Polymerase chain reaction-restriction fragment length polymorphism analysis was performed to assess the prevalence of the Ser/Cys polymorphism in the human 8-oxoguanine glycosylase (hOGG1 gene. We analyzed the samples from 246 ICM cases (the ICM group and another 246 age- and sex-matched volunteers with normal coronary artery function (the control group. Levels of 8-OHdG in participants' blood samples were 6.7 ± 1.7 and 3.0 ± 0.8 in the ICM and control groups, respectively (p < 0.05. Although there were no differences in allele frequency (p = 0.140, significant differences were present in the genotype distributions (p = 0.002. The Cys/Cys genotype correlated strongly with the risk of developing ICM (odds ratio, 2.2; 95% confidence interval, 1.4–3.3. Treating the Ser/Ser and Ser/Cys genotypes as members of the same group increased the predicted ICM risk for patients carrying the Cys/Cys genotype (odds ratio, 1.9; 95% confidence interval, 1.2–2.9. The serum level of 8-OHdG in the ICM group was higher than that in the control group (p < 0.05 and significantly increased in those carrying the Cys/Cys genotype (8.7 ± 1.7 for the Cys/Cys group, and 4.5 ± 0.8 for the Ser/Ser+Ser/Cys group; p < 0.05. Patients carrying the Cys/Cys genotype had a significantly increased risk of developing ICM. Serum levels of 8-OHdG were significantly increased in patients with ICM.

Non-invasive glucagon-like peptide-1 receptor imaging in pancreas with (18)F-Al labeled Cys(39)-exendin-4.

Science.gov (United States)

Mi, Baoming; Xu, Yuping; Pan, Donghui; Wang, Lizhen; Yang, Runlin; Yu, Chunjing; Wan, Weixing; Wu, Yiwei; Yang, Min

2016-02-26

Glucagon-like peptide-1 receptor (GLP-1R) is abundantly expressed on beta cells and may be an ideal target for the pancreas imaging. Monitoring the GLP-1R of pancreas could be benefit for understanding the pathophysiology of diabetes. In the present study, (18)F-Al labeled exendin-4 analog, (18)F-Al-NOTA-MAL-Cys(39)-exendin-4, was evaluated for PET imaging GLP-1R in the pancreas. The targeting of (18)F-Al labeled exendin-4 analog was examined in healthy and streptozotocin induced diabetic rats. Rats were injected with (18)F-Al-NOTA-MAL-Cys(39)-exendin-4 and microPET imaging was performed at 1 h postinjection, followed by ex vivo biodistribution. GLP-1R expression in pancreas was determined through post mortern examinations. The pancreas of healthy rats was readily visualized after administration of (18)F-Al-NOTA-MAL-Cys(39)-exendin-4, whereas the pancreas of diabetic rats, as well as those from rats co-injected with excess of unlabeled peptides, was barely visible by microPET. At 60 min postinjection, the pancreatic uptakes were 1.02 ± 0.15%ID/g and 0.23 ± 0.05%ID/g in healthy and diabetic rats respectively. Under block, the pancreatic uptakes of non-diabetic rats reduced to 0.21 ± 0.07%ID/g at the same time point. Biodistribution data and IHC staining confirmed the findings of the microPET imaging. The favorable preclinical data indicated that (18)F-Al-NOTA-MAL-Cys(39)-exendin-4may be suitable for non-invasive monitoring functional pancreatic beta cells. Copyright © 2016 Elsevier Inc. All rights reserved.

No evidence for association of dopamine D2 receptor variant (Ser311/Cys311) with major psychosis

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Tsukasa; Macciardi, F.M.; Badri, F. [Clarke Institute of Psychiatry, Ontario (Canada)] [and others

1996-07-26

We investigated a variant of the dopamine D2 receptor gene (Ser311/Cys311 substitution) in Caucasian patients with schizophrenia (n = 273), delusional disorder (n = 62), bipolar I affective disorder (n = 63), and controls (n = 255). No evidence for association between the receptor variant and any of the diseases was found, even when patients with younger age-of-onset (<25 years) were compared with controls. Futhermore, in a subgroup of schizophrenia patients whom we assessed for negative symptoms, those with the Cys allele did not differ from the remainder of the group. Also, the bipolar affective disorder patients with psychotic features did not show evidence for association with the receptor variant. Thus, our results do not provide evidence for an association between this D2 receptor variant and schizophrenia, or delusional disorder, or bipolar affective disorder. 11 refs., 1 tab.

The expression patterns of bromelain and AcCYS1 correlate with blackheart resistance in pineapple fruits submitted to postharvest chilling stress.

Science.gov (United States)

Raimbault, Astrid-Kim; Zuily-Fodil, Yasmine; Soler, Alain; Mora, Phillipe; Cruz de Carvalho, Maria H

2013-11-01

Blackheart is a physiological disorder induced by postharvest chilling storage during pineapple fruit export shipping. The aim of this study was to check the involvement of bromelain, the cysteine protease protein family abundantly present in pineapple fruits, and AcCYS1, an endogenous inhibitor of bromelain, in the development of blackheart. For this we checked the response to postharvest chilling treatment of two pineapple varieties (MD2 and Smooth Cayenne) differing in their resistance to blackheart. Quantitative RT-PCR analyses showed that postharvest chilling treatment induced a down-regulation of bromelain transcript accumulation in both varieties with the most dramatic drop in the resistant variety. Regarding AcCYS1 transcript accumulation, the varieties showed opposite trends with an up-regulation in the case of the resistant variety and a down-regulation in the susceptible one. Taken together our results suggest that the control of bromelain and AcCYS1 expression levels directly correlates to the resistance to blackheart development in pineapple fruits. Copyright © 2013 Elsevier GmbH. All rights reserved.

Purification and characterization of factor VIII 1,689-Cys: a nonfunctional cofactor occurring in a patient with severe hemophilia A.

Science.gov (United States)

O'Brien, D P; Tuddenham, E G

1989-06-01

We have purified the factor VIII from a CRM+ Hemophilia A plasma (90 U/dL VIII:Ag but 0 U/dL VIII:C) and analyzed the protein before and after thrombin activation by Western blotting with monoclonal antibodies (MoAbs). Normal or patient citrated plasma was ultracentrifuged, cryo-ethanol-precipitated and chromatographed on Sepharose 6B. The void volume fractions were reduced and subjected to ion exchange chromatography yielding material of specific activity approximately 1,000 U/mg protein (VIII:C or VIII:Ag). Factor VIII purified in this way from normal plasma is fully activatable by thrombin with proteolytic fragmentation as previously described by F. Rotblat et al (Biochemistry 24: 4294, 1985). Factor VIII 1,689-Cys has the normal distribution of factor VIII light and heavy chains prior to thrombin activation. After exposure to thrombin the heavy chain polypeptides were fully proteolysed but the light chain was totally resistant to cleavage. This is consistent with the demonstration in the patient's leucocyte DNA of a C to T transition in codon 1,689 converting Arg to Cys at the light chain thrombin cleavage site as previously described by J. Gitschier et al (Blood 72:1022, 1988). Uncleaved light chain of Factor VIII 1,689-Cys is not released from von Willebrand factor (vWF) by thrombin, but this is not the sole cause of the functional defect since the protein purified free of vWF has no coagulant activity. We conclude that the functional defect in factor VIII 1,689-Cys is a consequence of failure to release the acidic peptide from the light chain upon thrombin activation.

Translational Control of Host Gene Expression by a Cys-Motif Protein Encoded in a Bracovirus.

Directory of Open Access Journals (Sweden)

Eunseong Kim

Full Text Available Translational control is a strategy that various viruses use to manipulate their hosts to suppress acute antiviral response. Polydnaviruses, a group of insect double-stranded DNA viruses symbiotic to some endoparasitoid wasps, are divided into two genera: ichnovirus (IV and bracovirus (BV. In IV, some Cys-motif genes are known as host translation-inhibitory factors (HTIF. The genome of endoparasitoid wasp Cotesia plutellae contains a Cys-motif gene (Cp-TSP13 homologous to an HTIF known as teratocyte-secretory protein 14 (TSP14 of Microplitis croceipes. Cp-TSP13 consists of 129 amino acid residues with a predicted molecular weight of 13.987 kDa and pI value of 7.928. Genomic DNA region encoding its open reading frame has three introns. Cp-TSP13 possesses six conserved cysteine residues as other Cys-motif genes functioning as HTIF. Cp-TSP13 was expressed in Plutella xylostella larvae parasitized by C. plutellae. C. plutellae bracovirus (CpBV was purified and injected into non-parasitized P. xylostella that expressed Cp-TSP13. Cp-TSP13 was cloned into a eukaryotic expression vector and used to infect Sf9 cells to transiently express Cp-TSP13. The synthesized Cp-TSP13 protein was detected in culture broth. An overlaying experiment showed that the purified Cp-TSP13 entered hemocytes. It was localized in the cytosol. Recombinant Cp-TSP13 significantly inhibited protein synthesis of secretory proteins when it was added to in vitro cultured fat body. In addition, the recombinant Cp-TSP13 directly inhibited the translation of fat body mRNAs in in vitro translation assay using rabbit reticulocyte lysate. Moreover, the recombinant Cp-TSP13 significantly suppressed cellular immune responses by inhibiting hemocyte-spreading behavior. It also exhibited significant insecticidal activities by both injection and feeding routes. These results indicate that Cp-TSP13 is a viral HTIF.

Increase of (CdSe/ZnS)Cys quantum dot luminescence intensity in the presence of TPPS4 porphyrin

International Nuclear Information System (INIS)

Parra, Gustavo G.; Borissevitch, Iouri E.; Oleinikov, Vladimir A.

2012-01-01

Full text: Nanocrystal semiconductor particles or Quantum Dots (QD) possess extraordinary photophysical characteristics, such as extreme high fluorescence quantum yield and optical absorption and very narrow fluorescence band, which can be easily shifted by changing of QD particle size. Due to these characteristics, QD is promising for fluorescence cancer diagnostics and photodynamic treatment. The efficiency of these processes can be in- creased by energy transfer between QD and classic fluorescence probes and photosensitizers (PS). In this work we present on the study of the increase of (CdSe/ZnS)Cys quantum dot luminescence intensity, stimulated by interaction with TPPS 4 porphyrin. The optical absorption and steady-state and time-resolved fluorescence techniques were employed. Water soluble QD (CdSe/ZnS) with emission at 580 nm, functionalized with cysteine (Cys), were studied. TPPS 4 porphyrin was used as a stimulator of QD luminescence. All experiments were realized in PBS buffer (pH 7.3; 7.5 mM) in Milli-Q quality water. The TPPS 4 adding into the QD solutions until the 5μM concentration produced an increase in QD luminescence intensity and lifetime, while for TPPS 4 concentrations higher than 20μM the reduction of the fluorescence intensity was observed, the emission spectra and fluorescence decays profile being unchanged. This effect can not be due to the electrostatic interaction between (CdSe/ZnS)Cys and TPPS 4 because both, (CdSe/ZnS)Cys and TPPS 4 , are negatively charged. We suppose that TPPS 4 porphyrin interacts directly with QD (ZnS) shell, reducing the dangling bound number. This reduction decreases, in turn, the probability of nonradiative ways of the excitation energy dissipation. When the majority of dangling bound is occupied by the TPPS 4 molecules, the effect of QD luminescence reduction (quenching) by porphyrin predominates, probably, via the energy transfer from QD to TPPS 4 . However, because of complexity in the systems involving

An association between hOGG1 Ser326Cys polymorphism and the risk of bladder cancer in non-smokers: a meta-analysis

International Nuclear Information System (INIS)

Ji, Changwei; Liu, Zhao; Chen, Huimei; Guo, Hongqian; Liu, Changjian

2012-01-01

Bladder cancer results from complex interactions between many genetic and environment factors. The polymorphism Ser326Cys in hOGG1 gene has been reported to be associated with bladder cancer in some studies, though the results remain inconclusive. To explore this relationship of hOGG1 polymorphism and the susceptibility for bladder cancer and the impact of smoking exposures, a cumulative meta-analysis was performed in this study. We extracted the data from the Pubmed database up to January 9, 2012 using the search phrases “hOGG1, Ser326Cys polymorphism and bladder cancer”. Seven case–control studies were identified, including 2474 patients and 2408 controls. Four of them provided the analysis of smoking effects, with 1372 smokers and 947 non-smokers. The odds ratios (ORs) and associated 95 % confidence intervals (CIs) were calculated using fixed- or random- effects models. Regarding the overall association between the hOGG1 326Cys allele and bladder cancer risk, the meta-analysis did not reveal a significant effect in the additive model (OR: 1.06, 95 % CI: 0.96-1.26; p = 0.49), the recessive genetic model (OR: 1.05, 95 % CI: 0.65-1.70; p = 0.85) or the dominant genetic model (OR: 1.07, 95 % CI: 0.87-1.32; p = 0.53). Similarly, no significant relationship was observed in the stratified analysis by ethnicity, study design and Hardy-Weinberg equilibrium (all p > 0.05). In the non-smokers, however, hOGG1 326Cys allele significantly increased the risk for bladder cancer and the ORs in the additive model, homozygote contrast and recessive genetic model were 1.59 (p = 0.02), 2.53(p = 0.003) and 2.41(p = 0.0005), respectively. Nevertheless, in the smoker subgroup, similar findings could not be found in all genetic models (all p > 0.05). The association between the hOGG1 326Cys allele and bladder cancer was significant in non-smoker population, while was non-detectable in common or smoker populations. This meta-analysis suggests that the hOGG1 Ser326Cys polymorphism

An association between hOGG1 Ser326Cys polymorphism and the risk of bladder cancer in non-smokers: a meta-analysis

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Ji Changwei

2012-08-01

Full Text Available Abstract Background Bladder cancer results from complex interactions between many genetic and environment factors. The polymorphism Ser326Cys in hOGG1 gene has been reported to be associated with bladder cancer in some studies, though the results remain inconclusive. To explore this relationship of hOGG1 polymorphism and the susceptibility for bladder cancer and the impact of smoking exposures, a cumulative meta-analysis was performed in this study. Methods We extracted the data from the Pubmed database up to January 9, 2012 using the search phrases “hOGG1, Ser326Cys polymorphism and bladder cancer”. Seven case–control studies were identified, including 2474 patients and 2408 controls. Four of them provided the analysis of smoking effects, with 1372 smokers and 947 non-smokers. The odds ratios (ORs and associated 95 % confidence intervals (CIs were calculated using fixed- or random- effects models. Results Regarding the overall association between the hOGG1 326Cys allele and bladder cancer risk, the meta-analysis did not reveal a significant effect in the additive model (OR: 1.06, 95 % CI: 0.96-1.26; p = 0.49, the recessive genetic model (OR: 1.05, 95 % CI: 0.65-1.70; p = 0.85 or the dominant genetic model (OR: 1.07, 95 % CI: 0.87-1.32; p = 0.53. Similarly, no significant relationship was observed in the stratified analysis by ethnicity, study design and Hardy-Weinberg equilibrium (all p > 0.05. In the non-smokers, however, hOGG1 326Cys allele significantly increased the risk for bladder cancer and the ORs in the additive model, homozygote contrast and recessive genetic model were 1.59 (p = 0.02, 2.53(p = 0.003 and 2.41(p = 0.0005, respectively. Nevertheless, in the smoker subgroup, similar findings could not be found in all genetic models (all p > 0.05. Conclusions The association between the hOGG1 326Cys allele and bladder cancer was significant in non-smoker population, while was non-detectable in

The role of complement receptors type 1 (CR1, CD35) and 2 (CR2, CD21) in promoting C3 fragment deposition and membrane attack complex formation on normal peripheral human B cells

DEFF Research Database (Denmark)

Nielsen, Claus Henrik; Pedersen, Morten Løbner; Marquart, Hanne Vibeke Hansen

2002-01-01

Normal human B lymphocytes are known to activate the alternative pathway (AP) of complement, leading to C3-fragment deposition and membrane attack complex (MAC) formation. The process is mediated via complement receptor type 2 (CR2, CD21), with complement receptor type 1 (CR1, CD35) playing...... a subsidiary role. In this study, we examine the relative contributions of CR1 and CR2 to the deposition of C3 fragments and MAC on B lymphocytes under circumstances where all complement pathways are operational. C3-fragment deposition and MAC formation were assessed on human peripheral B lymphocytes...... in the presence of 30% autologous serum. Blocking the CR2 ligand-binding site with monoclonal antibody (mAb) FE8 resulted in significant reduction (37.9+/-11.9%) in C3-fragment deposition, whereas MAC formation was only marginally affected (12.1+/-22.2% reduction). Blocking the CR1 binding-site resulted...

Mild achondroplasia/hypochondroplasia with acanthosis nigricans, normal development, and a p.Ser348Cys FGFR3 mutation.

Science.gov (United States)

Couser, Natario L; Pande, Chetna K; Turcott, Christie M; Spector, Elaine B; Aylsworth, Arthur S; Powell, Cynthia M

2017-04-01

Pathogenic allelic variants in the fibroblast growth factor receptor 3 (FGFR3) gene have been associated with a number of phenotypes including achondroplasia, hypochondroplasia, thanatophoric dysplasia, Crouzon syndrome with acanthosis nigricans (Crouzonodermoskeletal syndrome), and SADDAN (severe achondroplasia with developmental delay and acanthosis nigricans). Crouzon syndrome with acanthosis nigricans is caused by the pathogenic variant c.1172C>A (p.Ala391Glu) in the FGFR3 gene. The p.Lys650Thr pathogenic variant in FGFR3 has been linked to acanthosis nigricans without significant craniofacial or skeletal abnormalities. Recently, an infant with achondroplasia and a novel p.Ser348Cys FGFR3 mutation was reported. We describe the clinical history of an 8-year-old child with a skeletal dysplasia in the achondroplasia-hypochondroplasia spectrum, acanthosis nigricans, typical development, and the recently described p.Ser348Cys FGFR3 mutation. © 2017 Wiley Periodicals, Inc.

Three members of the 6-cys protein family of Plasmodium play a role in gamete fertility.

NARCIS (Netherlands)

Dijk, M.R. van; Schaijk, B.C.L. van; Khan, S.M.; Dooren, M.W. van; Ramesar, J.; Kaczanowski, S.; Gemert, G.J.A. van; Kroeze, H.; Stunnenberg, H.G.; Eling, W.M.C.; Sauerwein, R.W.; Waters, A.P.; Janse, C.J.

2010-01-01

The process of fertilization is critically dependent on the mutual recognition of gametes and in Plasmodium, the male gamete surface protein P48/45 is vital to this process. This protein belongs to a family of 10 structurally related proteins, the so called 6-cys family. To identify the role of

Circulating Angiopoietin-2 and Its Soluble Receptor Tie-2 Concentrations Are Related to Renal Function in Two Population-Based Cohorts.

Science.gov (United States)

Hennings, Anna; Hannemann, Anke; Rettig, Rainer; Dörr, Marcus; Nauck, Matthias; Völzke, Henry; Lerch, Markus M; Lieb, Wolfgang; Friedrich, Nele

2016-01-01

An intact angiopoietin/Tie-2 ligand receptor system is indispensable for life. High circulating angiopoietin-2 (Ang-2) concentrations are strongly associated with kidney disease involving the progressive loss of glomerular filtration. The aim of our study was to investigate the associations between renal function and serum Ang-2 or serum Tie-2 concentrations in the general population. Data of 3081 and 4088 subjects from two population-based studies, the Study of Health in Pomerania (SHIP-1) and SHIP-Trend, were used. Renal function was assessed by serum creatinine, cystatin C concentration, creatinine-based estimated glomerular filtration rate [eGFR(crea)], cystatin C-based eGFR [eGFR(cys)] and urinary albumin-to-creatinine ratio (uACR). Analyses of variance and linear regression models were calculated. In both cohorts, strong positive associations between serum cystatin C concentrations and serum Ang-2 or Tie-2 concentrations as well as inverse associations between eGFR(cys) and serum Ang-2 or Tie-2 concentrations were found. These relations were also present in a subpopulation without hypertension or diabetes mellitus type 2. Furthermore, we detected weak U-shaped associations between serum creatinine concentrations or eGFR(crea) and serum Ang-2 concentrations. With respect to uACR a strong positive association with serum Ang-2 concentrations was revealed. Serum Ang-2 concentrations are strongly associated with sensitive parameters of renal impairment like serum cystatin C, uACR and eGFR(cys). These findings persisted even after exclusion of subjects with hypertension or diabetes mellitus type 2, conditions that predispose to chronic renal disease and are associated with increased Ang-2 concentrations. Interestingly, we did not detect the same strong relations between serum creatinine and eGFR(crea) with serum Ang-2 concentration. Additionally, significant association of serum Tie-2 concentrations with cystatin C and eGFR(cys) were detected.

Circulating Angiopoietin-2 and Its Soluble Receptor Tie-2 Concentrations Are Related to Renal Function in Two Population-Based Cohorts.

Directory of Open Access Journals (Sweden)

Anna Hennings

Full Text Available An intact angiopoietin/Tie-2 ligand receptor system is indispensable for life. High circulating angiopoietin-2 (Ang-2 concentrations are strongly associated with kidney disease involving the progressive loss of glomerular filtration. The aim of our study was to investigate the associations between renal function and serum Ang-2 or serum Tie-2 concentrations in the general population.Data of 3081 and 4088 subjects from two population-based studies, the Study of Health in Pomerania (SHIP-1 and SHIP-Trend, were used. Renal function was assessed by serum creatinine, cystatin C concentration, creatinine-based estimated glomerular filtration rate [eGFR(crea], cystatin C-based eGFR [eGFR(cys] and urinary albumin-to-creatinine ratio (uACR. Analyses of variance and linear regression models were calculated.In both cohorts, strong positive associations between serum cystatin C concentrations and serum Ang-2 or Tie-2 concentrations as well as inverse associations between eGFR(cys and serum Ang-2 or Tie-2 concentrations were found. These relations were also present in a subpopulation without hypertension or diabetes mellitus type 2. Furthermore, we detected weak U-shaped associations between serum creatinine concentrations or eGFR(crea and serum Ang-2 concentrations. With respect to uACR a strong positive association with serum Ang-2 concentrations was revealed.Serum Ang-2 concentrations are strongly associated with sensitive parameters of renal impairment like serum cystatin C, uACR and eGFR(cys. These findings persisted even after exclusion of subjects with hypertension or diabetes mellitus type 2, conditions that predispose to chronic renal disease and are associated with increased Ang-2 concentrations. Interestingly, we did not detect the same strong relations between serum creatinine and eGFR(crea with serum Ang-2 concentration. Additionally, significant association of serum Tie-2 concentrations with cystatin C and eGFR(cys were detected.

Therapeutic effect of continuous exercise training program on serum creatinine concentration in men with hypertension: a randomized controlled trial.

Science.gov (United States)

Sikiru, L; Okoye, G C

2014-09-01

Creatinine (Cr) has been implicated as an independent predictor of hypertension and exercise has been reported as adjunct therapy for hypertension. The purpose of the present study was to investigate the effect of continuous training programme on blood pressure and serum creatinine concentration in black African subjects with hypertension. Three hundred and fifty seven male patients with mild to moderate (systolic blood pressure [SBP] between 140-180 & diastolic blood pressure [DBP] between 90-109 mmHg) essential hypertension were age matched and randomly grouped into continuous & control groups. The continuous group involved in an 8 weeks continuous training (60-79% HR reserve) of between 45 minutes to 60 minutes, 3 times per week, while the control group remain sedentary. SBP, DBP, VO2max, serum Cr, body mass index (BMI), waist hip ratio (WHR) and percent (%) body fat. Analysis of covariance (ANCOVA) and Pearson correlation tests were used in data analysis. Findings of the study revealed significant decreased effects of continuous training programme on SBP, DBP, Cr, BMI, WHR, % body fat and significant increase in VO2max at pexercise training as a multi-therapy in the down regulation of blood pressure, serum Cr, body size and body fat in hypertension.

Relationship between acute kidney injury and serum procalcitonin (PCT) concentration in critically ill patients with influenza infection.

Science.gov (United States)

Rodríguez, A; Reyes, L F; Monclou, J; Suberviola, B; Bodí, M; Sirgo, G; Solé-Violán, J; Guardiola, J; Barahona, D; Díaz, E; Martín-Loeches, I; Restrepo, M I

2018-02-09

Serum procalcitonin (PCT) concentration could be increased in patients with renal dysfunction in the absence of bacterial infection. To determine the interactions among serum renal biomarkers of acute kidney injury (AKI) and serum PCT concentration, in patients admitted to the intensive care unit (ICU) due to lung influenza infection. Secondary analysis of a prospective multicentre observational study. 148 Spanish ICUs. ICU patients admitted with influenza infection without bacterial co-infection. Clinical, laboratory and hemodynamic variables were recorded. AKI was classified as AKI I or II based on creatinine (Cr) concentrations (≥1.60-2.50mg/dL and Cr≥2.51-3.99mg/dL, respectively). Patients with chronic renal disease, receiving renal replacement treatment or with Cr>4mg/dL were excluded. Spearman's correlation, simple and multiple linear regression analysis were performed. None. Out of 663 patients included in the study, 52 (8.2%) and 10 (1.6%) developed AKI I and II, respectively. Patients with AKI were significantly older, had more comorbid conditions and were more severally ill. PCT concentrations were higher in patients with AKI (2.62 [0.60-10.0]ng/mL vs. 0.40 [0.13-1.20]ng/mL, p=0.002). Weak correlations between Cr/PCT (rho=0.18) and Urea (U)/PCT (rho=0.19) were identified. Simple linear regression showed poor interaction between Cr/U and PCT concentrations (Cr R 2 =0.03 and U R 2 =0.018). Similar results were observed during multiple linear regression analysis (Cr R 2 =0.046 and U R 2 =0.013). Although PCT concentrations were slightly higher in patients with AKI, high PCT concentrations are not explained by AKI and could be warning sign of a potential bacterial infection. Copyright © 2018 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

Three members of the 6-cys protein family of Plasmodium play a role in gamete fertility.

Directory of Open Access Journals (Sweden)

Melissa R van Dijk

2010-04-01

Full Text Available The process of fertilization is critically dependent on the mutual recognition of gametes and in Plasmodium, the male gamete surface protein P48/45 is vital to this process. This protein belongs to a family of 10 structurally related proteins, the so called 6-cys family. To identify the role of additional members of this family in Plasmodium fertilisation, we performed genetic and functional analysis on the five members of the 6-cys family that are transcribed during the gametocyte stage of P. berghei. This analysis revealed that in addition to P48/45, two members (P230 and P47 also play an essential role in the process of parasite fertilization. Mating studies between parasites lacking P230, P48/45 or P47 demonstrate that P230, like P48/45, is a male fertility factor, consistent with the previous demonstration of a protein complex containing both P48/45 and P230. In contrast, disruption of P47 results in a strong reduction of female fertility, while males remain unaffected. Further analysis revealed that gametes of mutants lacking expression of p48/45 or p230 or p47 are unable to either recognise or attach to each other. Disruption of the paralog of p230, p230p, also specifically expressed in gametocytes, had no observable effect on fertilization. These results indicate that the P. berghei 6-cys family contains a number of proteins that are either male or female specific ligands that play an important role in gamete recognition and/or attachment. The implications of low levels of fertilisation that exist even in the absence of these proteins, indicating alternative pathways of fertilisation, as well as positive selection acting on these proteins, are discussed in the context of targeting these proteins as transmission blocking vaccine candidates.

Functional implications of the p.Cys680Arg mutation in the MLH1 mismatch repair protein

DEFF Research Database (Denmark)

Dominguez-Valentin, Mev; Drost, Mark; Therkildsen, Christina

2014-01-01

>C missense mutation in exon 18 of the human MLH1 gene and biochemically characterization of the p.Cys680Arg mutant MLH1 protein to implicate it in the pathogenicity of the Lynch syndrome (LS). We show that the mutation is deficient in DNA mismatch repair and, therefore, contributing to LS in the carriers....

The association of plasma cysteine and gamma-glutamyltransferase with BMI and obesity.

LENUS (Irish Health Repository)

Elshorbagy, Amany K

2009-07-01

We recently reported a strong positive association of plasma total cysteine (tCys) with fat mass in over 5,000 subjects. As gamma-glutamyltransferase (GGT) enzyme increases cysteine availability by catalyzing glutathione breakdown and is positively associated with BMI and adiposity, we hypothesized that GGT might explain the association of tCys with adiposity. To study whether the associations of tCys and serum GGT with BMI and obesity were interrelated we conducted a cross-sectional study using data from 1,550 subjects recruited from nine European countries in the COMAC project. Multiple linear and logistic regression models and concentration-response curves were used. In age and sex-adjusted analyses, tCys showed strong positive associations with BMI (partial r = 0.19, P < 0.001), and obesity (odds ratio (OR) for 4th vs. 1st tCys quartile: 2.8; 95% confidence interval: 1.6-5.0, P < 0.001), both of which remained robust after adjustment for GGT and other metabolic and lifestyle confounders. Serum GGT was also a positive predictor of BMI (partial r = 0.17, P < 0.001) and obesity (OR for 4th vs. 1st GGT quartile: 4.8; 95% confidence interval: 2.5-9.2, P < 0.001), independent of tCys. However, the associations of GGT with BMI and obesity were weakened by adjustment for obesity-related factors such as serum lipids and blood pressure. These results indicate that tCys is a strong positive predictor of BMI and obesity, independent of GGT and other obesity-related factors. We also suggest that the association of serum GGT with BMI and obesity is unrelated to the role of GGT in cysteine turnover. The potential link between cysteine and fat metabolism should be further evaluated.

Contribution of ARLTS1 Cys148Arg (T442C variant with prostate cancer risk and ARLTS1 function in prostate cancer cells.

Directory of Open Access Journals (Sweden)

Sanna Siltanen

Full Text Available ARLTS1 is a recently characterized tumor suppressor gene at 13q14.3, a region frequently deleted in both sporadic and hereditary prostate cancer (PCa. ARLTS1 variants, especially Cys148Arg (T442C, increase susceptibility to different cancers, including PCa. In this study the role of Cys148Arg substitution was investigated as a risk factor for PCa using both genetic and functional analysis. Cys148Arg genotypes and expression of the ARLTS1 were explored in a large set of familial and unselected PCa cases, clinical tumor samples, xenografts, prostate cancer cell lines and benign prostatic hyperplasia (BPH samples. The frequency of the variant genotype CC was significantly higher in familial (OR = 1.67, 95% CI = 1.08-2.56, P = 0.019 and unselected patients (OR = 1.52, 95% CI = 1.18-1.97, P = 0.001 and the overall risk was increased (OR = 1.54, 95% CI = 1.20-1.98, P = 0.0007. Additional analysis with clinicopathological data revealed an association with an aggressive disease (OR = 1.28, 95% CI = 1.05-∞, P = 0.02. The CC genotype of the Cys148Arg variant was also contributing to the lowered ARLTS1 expression status in lymphoblastoid cells from familial patients. In addition significantly lowered ARLTS1 expression was observed in clinical tumor samples compared to BPH samples (P = 0.01. The ARLTS1 co-expression signature based on previously published microarray data was generated from 1587 cancer samples confirming the low expression of ARLTS1 in PCa and showed that ARLTS1 expression was strongly associated with immune processes. This study provides strong confirmation of the important role of ARLTS1 Cys148Arg variant as a contributor in PCa predisposition and a potential marker for aggressive disease outcome.

Efeito do citrato e taurina em meio CR2aa no desenvolvimento de embriões bovinos fecundados in vitro Effect of citrate and taurine added to CR2aa medium on the development of in vitro-fertilized bovine embryos

Directory of Open Access Journals (Sweden)

L.S.A. Camargo

2009-02-01

Full Text Available Avaliou-se o efeito do citrato em meio CR2aa suplementado com soro fetal bovino (SFB ou livre de proteínas séricas e sua associação com taurina no desenvolvimento de embriões bovinos fecundados in vitro. Embriões foram cultivados em CR2aa contendo 0, 0,5, 1,0 e 3,0mM citrato, suplementado com 10% SFB (experimento 1 ou com álcool polivinil (PVA; experimento 2. No terceiro experimento, embriões foram cultivados em meio com 0,5mM citrato, ou 7mM taurina, ou com a associação de ambos, suplementado com SFB. Os cultivos foram realizados com células do cumulus em ambiente a 38,8ºC com 5% de CO2 em ar atmosférico. Melhora no desenvolvimento embrionário foi observado no cultivo de embriões em CR2aa com 0,5 e 1,0mM citrato na ausência de SFB (P0,05 a produção de embriões ou o número de células. Citrato em meio CR2aa pode ser uma alternativa para cultivo embrionário em condições atmosféricas com 5% de CO2 em ar na ausência de proteína sérica.The effect of citrate added to CR2aa medium supplemented with fetal calf serum (FCS or serum-proteinfree and its association with taurine on the development of in vitro-fertilized bovine embryos was evaluated. Embryos were cultured with 0, 0.5, 1.0, and 3.0mM citrate, in CR2aa supplemented with 10% FCS (experiment 1, or polyvinyl alcohol (PVA; experiment 2. In experiment 3, embryos were cultured with 0.5mM citrate, 7.0mM taurine or with association of both, in medium supplemented with FCS. Embryo culture was performed with cumulus cells at 38.8ºC in 5% CO2 under air for all experiments. Positive effect on embryo development was only observed with 0.5 and 1.0mM citrate in FCS-free CR2aa (P0.05 embryo rate nor total cell number. Citrate in CR2aa medium can be an alternative for serumfree embryo culture under 5% CO2 in air, absence of serum protein.

Increase of chromium tolerance in Scenedesmus acutus after sulfur starvation: Chromium uptake and compartmentalization in two strains with different sensitivities to Cr(VI).

Science.gov (United States)

Marieschi, M; Gorbi, G; Zanni, C; Sardella, A; Torelli, A

2015-10-01

In photosynthetic organisms sulfate constitutes the main sulfur source for the biosynthesis of GSH and its precursor Cys. Hence, sulfur availability can modulate the capacity to cope with environmental stresses, a phenomenon known as SIR/SED (Sulfur Induced Resistance or Sulfur Enhanced Defence). Since chromate may compete for sulfate transport into the cells, in this study chromium accumulation and tolerance were investigated in relation to sulfur availability in two strains of the unicellular green alga Scenedesmus acutus with different Cr-sensitivities. Paradoxically, sulfur deprivation has been demonstrated to induce a transient increase of Cr-tolerance in both strains. Sulfur deprivation is known to enhance the sulfate uptake/assimilation pathway leading to important consequences on Cr-tolerance: (i) reduced chromate uptake due to the induction of high affinity sulfate transporters (ii) higher production of cysteine and GSH which can play a role both through the formation of unsoluble complexes and their sequestration in inert compartments. To investigate the role of the above mentioned mechanisms, Cr accumulation in total cells and in different cell compartments (cell wall, membranes, soluble and miscellaneous fractions) was analyzed in both sulfur-starved and unstarved cells. Both strains mainly accumulated chromium in the soluble fraction, but the uptake was higher in the wild-type. In this type a short period of sulfur starvation before Cr(VI) treatment lowered chromium accumulation to the level observed in the unstarved Cr-tolerant strain, in which Cr uptake seems instead less influenced by S-starvation, since no significant decrease was observed. The increase in Cr-tolerance following S-starvation seems thus to rely on different mechanisms in the two strains, suggesting the induction of a mechanism constitutively active in the Cr-tolerant strain, maybe a high affinity sulfate transporter also in the wild-type. Changes observed in the cell wall and

A novel photoelectrochemical immunosensor by integration of nanobody and TiO2 nanotubes for sensitive detection of serum cystatin C

International Nuclear Information System (INIS)

Mi, Li; Wang, Pingyan; Yan, Junrong; Qian, Jing; Lu, Jusheng; Yu, Jiachao; Wang, Yuzhen; Liu, Hong; Zhu, Min; Wan, Yakun; Liu, Songqin

2016-01-01

Cystatin C (CysC) is a sensitive marker for the estimation of the glomerular filtration rate and the clinical diagnosis of different diseases. In this paper, CysC-specific nanobodies (Nbs) were isolated from a phage display nanobody library. A simple and sensitive photoelectrochemical immunosensor based on TiO 2 nanotube arrays (TNAs) was proposed for the sensitive detection of CysC. The TiO 2 nanotube arrays deposited by electrochemical anodization displayed a high and stable photocurrent response under irradiation. After coupling CysC-specific nanobody to TNA (Nb/TNA), the proposed immunosensor for CysC can be utilized for tracking the photocurrent change of Nb/TNA caused by immunoreactions between CysC and the immobilized CysC-specific Nb. This allowed for the determination of CysC with a calibration range from 0.72 pM to 7.19 nM. The variation of the photocurrent was in a linear relationship with the logarithm of the CysC concentration in the range of 0.72 pM–3.6 nM. The immunosensor had a correlation coefficient of 0.97 and a detection limit of 0.14 pM at a signal-to-noise ratio of 3. The proposed immunosensor showed satisfactory intra- and inter-assay accuracy, high selectivity and good stability. As a result, this proposed strategy would offer a novel and simple approach for the detection of immunoreactions, provide new insights in popularizing the diagnosis of CysC, and extend the application of TiO 2 nanotubes. - Highlights: • CysC-specific nanobody to CysC is isolated from phage display nanobody library. • A photoelectrochemical immunosensor for CysC develops by Nb modified TNA. • An excellent sensitivity and good selectivity of CysC sensing was obtained.

Non-invasive glucagon-like peptide-1 receptor imaging in pancreas with {sup 18}F-Al labeled Cys{sup 39}-exendin-4

Energy Technology Data Exchange (ETDEWEB)

Mi, Baoming [Department of Nuclear Medicine, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 215006 (China); Department of Nuclear Medicine, Affiliated Hospital of Jiangnan University (Wuxi 4th People' s Hospital), Wuxi, Jiangsu, 214062 (China); Xu, Yuping [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu, 214063 (China); Nanjing Medical University, Nanjing, Jiangsu, 210029 (China); Pan, Donghui; Wang, Lizhen; Yang, Runlin [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu, 214063 (China); Yu, Chunjing; Wan, Weixing [Department of Nuclear Medicine, Affiliated Hospital of Jiangnan University (Wuxi 4th People' s Hospital), Wuxi, Jiangsu, 214062 (China); Wu, Yiwei, E-mail: wuyiwei3988@gmail.com [Department of Nuclear Medicine, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 215006 (China); Yang, Min, E-mail: ymzfk@yahoo.com.hk [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu, 214063 (China); Nanjing Medical University, Nanjing, Jiangsu, 210029 (China)

2016-02-26

Purpose: Glucagon-like peptide-1 receptor (GLP-1R) is abundantly expressed on beta cells and may be an ideal target for the pancreas imaging. Monitoring the GLP-1R of pancreas could be benefit for understanding the pathophysiology of diabetes. In the present study, {sup 18}F-Al labeled exendin-4 analog, {sup 18}F-Al-NOTA-MAL-Cys{sup 39}-exendin-4, was evaluated for PET imaging GLP-1R in the pancreas. Methods: The targeting of {sup 18}F-Al labeled exendin-4 analog was examined in healthy and streptozotocin induced diabetic rats. Rats were injected with {sup 18}F-Al-NOTA-MAL-Cys{sup 39}-exendin-4 and microPET imaging was performed at 1 h postinjection, followed by ex vivo biodistribution. GLP-1R expression in pancreas was determined through post mortern examinations. Results: The pancreas of healthy rats was readily visualized after administration of {sup 18}F-Al-NOTA-MAL-Cys{sup 39}-exendin-4, whereas the pancreas of diabetic rats, as well as those from rats co-injected with excess of unlabeled peptides, was barely visible by microPET. At 60 min postinjection, the pancreatic uptakes were 1.02 ± 0.15%ID/g and 0.23 ± 0.05%ID/g in healthy and diabetic rats respectively. Under block, the pancreatic uptakes of non-diabetic rats reduced to 0.21 ± 0.07%ID/g at the same time point. Biodistribution data and IHC staining confirmed the findings of the microPET imaging. Conclusion: The favorable preclinical data indicated that {sup 18}F-Al-NOTA-MAL-Cys{sup 39}-exendin-4may be suitable for non-invasive monitoring functional pancreatic beta cells.

The Significance of Serum beta2-Microglobulin Measurement in Various Renal Diseases

Energy Technology Data Exchange (ETDEWEB)

Koong, Sung Soo; Oh, Ha Yong; Han, Jin Suk; Lee, Jung Sang [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1985-03-15

To evaluate change of serum beta{sub 2}-microglobulin concentration (sbeta{sub 2}-MG) and the usefulness of sbeta{sub 2}-MG and sbeta{sub 2}-MG/serum creatinine concentration (sCr) ratio in various renal diseases, sbeta{sub 2}-MG and sCr were measured in 25 normal controls and 90 patients of various renal diseases (16 cases of glomerulonephritis, 12 cases of acute renal failure, 8 cases of chronic renal failure, 24 cases of nephrotic syndrome, 15 cases of tubulointerstitial diseases and 15 cases of lupus nephritis) using Phadebas beta{sub 2}-Micro Test kits. The results were as follows; 1) In normal control, the mean value of sbeta{sub 2}-MG was 1.65+-0.41 mg/l and the mean value of sbeta{sub 2}-MG/sCr ratio was 0.14+-0.05. 2) In various renal diseases, the mean value of sbeta{sub 2}-MG was 6.74+-5.47 mg/l. The mean value of sbeta{sub 2}-MG/sCr ratio was 0.24+-0.11 and significantly elevated than that of normal contro1. (P<0.05). 3) The correlation between sbeta-2-MG and sCr in glomerular and tubulointerstitial disease was log sbeta{sub 2}-MG=0.90 log sCr-0.48 and its correlation coefficient was 0.78 (P<0.05). 4) In glomerular disease, the correlation between sbeta{sub 2}-MG and sCr was log sbeta{sub 2}-MG=0.89 log sCr-0.46 (r-0.76) and in tubulointerstitial disease, it was log sbeta{sub 2}-MG=0.95 1og sCr-0.59 (r-0.87). There was no significant difference between the two groups (p<0.05). 5) Among 32 cases of glomerular and tubulointerstitial disease patients, whose sCr was within normal range, 17 cases showed elevated sbeta{sub 2}-MG. The mean values of sbeta{sub 2}-MG/sCr ratio in these patients was 0.30+-0.14 and significantly elevated than that of normal control (p<0.05). 6) In 15 cases of lupus nephritis, 12 cases showed elevated sbeta{sub 2}-MG with normal sCr and 12 cases showed elevated sbeta{sub 2}-MG/sCr ratio. With above results, It was found that the sbeta{sub 2}-MG can be used as an index of glomerular filtration rate as in the case of sCr and thats

Overexpression of MpCYS4, a phytocystatin gene from Malus prunifolia (Willd.) Borkh., delays natural and stress-induced leaf senescence in apple.

Science.gov (United States)

Tan, Yanxiao; Yang, Yingli; Li, Chao; Liang, Bowen; Li, Mingjun; Ma, Fengwang

2017-06-01

Phytocystatins are a well-characterized class of naturally occurring protease inhibitors that prevent the catalysis of papain-like cysteine proteases. The action of cystatins in stress tolerance has been studied intensively, but relatively little is known about their functions in plants during leaf senescence. Here, we examined the potential roles of the apple cystatin, MpCYS4, in leaf photosynthesis as well as the concentrations and composition of leaf proteins when plants encounter natural or stress-induced senescence. Overexpression of this gene in apple rootstock M26 effectively slowed the senescence-related declines in photosynthetic activity and chlorophyll concentrations and prevented the action of cysteine proteinases during the process of degrading proteins (e.g., Rubisco) in senescing leaves. Moreover, MpCYS4 alleviated the associated oxidative damage and enhanced the capacity of plants to eliminate reactive oxygen species by activating antioxidant enzymes such as ascorbate peroxidase, peroxidase, and catalase. Consequently, plant cells were protected against damage from free radicals during leaf senescence. Based on these results, we conclude that MpCYS4 functions in delaying natural and stress-induced senescence of apple leaves. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

A Structural and Mutagenic Blueprint for Molecular Recognition of Strychnine and d-Tubocurarine by Different Cys-Loop Receptors

NARCIS (Netherlands)

Brams, M.; Pandya, A.; Kuzmin, D.; van Elk, R.; Krijnen, L.; Yakel, J.L.; Tsetlin, V.; Smit, A.B.; Ulens, C.

2011-01-01

Cys-loop receptors (CLR) are pentameric ligand-gated ion channels that mediate fast excitatory or inhibitory transmission in the nervous system. Strychnine and d-tubocurarine (d-TC) are neurotoxins that have been highly instrumental in decades of research on glycine receptors (GlyR) and nicotinic

Trace element analysis of human blood serum by neutron activation analysis

International Nuclear Information System (INIS)

Nakahara, H.; Nagame, Y.; Yoshizawa, Y.; Oda, H.; Gotoh, S.; Murakami, Y.

1979-01-01

An attempt was made to determine if there is any correlation between trace element concentrations in human blood serum and some specific diseases. The serum samples of the patients suffering from cancer, Down syndrome, and Banti syndrome were analyzed by the neutron activation method and compared with the trace element concentrations observed among clinically healthy men. The cancer patients had concentrations in Rb, Mn, Fe, Co, Cu, Zn, Al and Se below normal. The Down syndrome patients were found to have similar deficiencies in Cr, Mn, Fe, Co, Zn, Cu and Sb. (author)

A novel photoelectrochemical immunosensor by integration of nanobody and TiO{sub 2} nanotubes for sensitive detection of serum cystatin C

Energy Technology Data Exchange (ETDEWEB)

Mi, Li [School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China); Wang, Pingyan; Yan, Junrong [Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203 (China); Qian, Jing; Lu, Jusheng; Yu, Jiachao [School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China); Wang, Yuzhen; Liu, Hong [Plexera LLC, WA 98072 (United States); Zhu, Min [Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203 (China); Wan, Yakun, E-mail: ywansystemsbiology@gmail.com [Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203 (China); Jiangsu Nanobody Engineering and Research Center, Nantong 226010 (China); Liu, Songqin, E-mail: liusq@seu.edu.cn [School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China)

2016-01-01

Cystatin C (CysC) is a sensitive marker for the estimation of the glomerular filtration rate and the clinical diagnosis of different diseases. In this paper, CysC-specific nanobodies (Nbs) were isolated from a phage display nanobody library. A simple and sensitive photoelectrochemical immunosensor based on TiO{sub 2} nanotube arrays (TNAs) was proposed for the sensitive detection of CysC. The TiO{sub 2} nanotube arrays deposited by electrochemical anodization displayed a high and stable photocurrent response under irradiation. After coupling CysC-specific nanobody to TNA (Nb/TNA), the proposed immunosensor for CysC can be utilized for tracking the photocurrent change of Nb/TNA caused by immunoreactions between CysC and the immobilized CysC-specific Nb. This allowed for the determination of CysC with a calibration range from 0.72 pM to 7.19 nM. The variation of the photocurrent was in a linear relationship with the logarithm of the CysC concentration in the range of 0.72 pM–3.6 nM. The immunosensor had a correlation coefficient of 0.97 and a detection limit of 0.14 pM at a signal-to-noise ratio of 3. The proposed immunosensor showed satisfactory intra- and inter-assay accuracy, high selectivity and good stability. As a result, this proposed strategy would offer a novel and simple approach for the detection of immunoreactions, provide new insights in popularizing the diagnosis of CysC, and extend the application of TiO{sub 2} nanotubes. - Highlights: • CysC-specific nanobody to CysC is isolated from phage display nanobody library. • A photoelectrochemical immunosensor for CysC develops by Nb modified TNA. • An excellent sensitivity and good selectivity of CysC sensing was obtained.

Electrospray ionisation mass spectrometry facilitates detection of fibrinogen (Bbeta 14 Arg --> Cys) mutation in a family with thrombosis.

Science.gov (United States)

Brennan, S O; Hammonds, B; Spearing, R; George, P M

1997-12-01

We report the first direct detection of a fibrinogen mutation by electrospray ionisation mass spectrometry. The propositus, from a family with a history of thrombosis, came to attention after a pulmonary embolism subsequent to a spontaneous abortion. Prolonged thrombin (41 s) and reptilase times (26 s) together with an impairment of fibrinopeptide B release suggested a mutation at the thrombin cleavage site of the Bbeta chain. Direct mass analysis of purified fibrin chains from a thrombin induced clot showed that 50% of the Bbeta chains remained uncleaved. The measured mass of the mono sialo isoform of this uncleaved chain was 54150 Da, compared to a value of 54198 Da for normal Bbeta chains. This decrease of 48 Da in the intact protein is indicative of either a Bbeta 14 Arg to Cys, or Arg to Leu substitution. Heterozygosity for the Bbeta 14 Arg --> Cys mutation was verified by PCR amplification and DNA sequence analysis.

Increase of (CdSe/ZnS)Cys quantum dot luminescence intensity in the presence of TPPS{sub 4} porphyrin

Energy Technology Data Exchange (ETDEWEB)

Parra, Gustavo G.; Borissevitch, Iouri E. [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Filosofia, Ciencias e Letras de Ribeirao Preto. Dept. de Fisica; Kuzmin, Vladimir A. [Emanuel Institute of Biophysical Chemistry, RAS-RU, Moscow (Russian Federation); Oleinikov, Vladimir A. [Shemyakin and Ovchinnikov Institute of Biooganic Cemistry, RAS-RU, Moscow (Russian Federation)

2012-07-01

Full text: Nanocrystal semiconductor particles or Quantum Dots (QD) possess extraordinary photophysical characteristics, such as extreme high fluorescence quantum yield and optical absorption and very narrow fluorescence band, which can be easily shifted by changing of QD particle size. Due to these characteristics, QD is promising for fluorescence cancer diagnostics and photodynamic treatment. The efficiency of these processes can be in- creased by energy transfer between QD and classic fluorescence probes and photosensitizers (PS). In this work we present on the study of the increase of (CdSe/ZnS)Cys quantum dot luminescence intensity, stimulated by interaction with TPPS{sub 4} porphyrin. The optical absorption and steady-state and time-resolved fluorescence techniques were employed. Water soluble QD (CdSe/ZnS) with emission at 580 nm, functionalized with cysteine (Cys), were studied. TPPS{sub 4} porphyrin was used as a stimulator of QD luminescence. All experiments were realized in PBS buffer (pH 7.3; 7.5 mM) in Milli-Q quality water. The TPPS{sub 4} adding into the QD solutions until the 5{mu}M concentration produced an increase in QD luminescence intensity and lifetime, while for TPPS{sub 4} concentrations higher than 20{mu}M the reduction of the fluorescence intensity was observed, the emission spectra and fluorescence decays profile being unchanged. This effect can not be due to the electrostatic interaction between (CdSe/ZnS)Cys and TPPS{sub 4} because both, (CdSe/ZnS)Cys and TPPS{sub 4}, are negatively charged. We suppose that TPPS{sub 4} porphyrin interacts directly with QD (ZnS) shell, reducing the dangling bound number. This reduction decreases, in turn, the probability of nonradiative ways of the excitation energy dissipation. When the majority of dangling bound is occupied by the TPPS{sub 4} molecules, the effect of QD luminescence reduction (quenching) by porphyrin predominates, probably, via the energy transfer from QD to TPPS{sub 4}. However

Interaction of complement-solubilized immune complexes with CR1 receptors on human erythrocytes. The binding reaction

DEFF Research Database (Denmark)

Jepsen, H H; Svehag, S E; Jarlbaek, L

1986-01-01

showed no binding. IC solubilized in 50% human serum in the presence of autologous RBC bound rapidly to RBC-CR1, with maximal binding within less than 1 min at 37 degrees C. Release of CR1-bound IC under these conditions occurred slowly, requiring more than 30 min. Only binding of 'partially' solubilized...... of an intact classical pathway in preparing the IC for binding to RBC-CR1. C-solubilized IC could be absorbed to solid-phase conglutinin or antibody to C3c and C4c, and these ligands were able to inhibit the binding of solubilized IC to RBC. Heparin also exerted a marked, dose-dependent inhibitory effect...

A novel photoelectrochemical immunosensor by integration of nanobody and TiO₂ nanotubes for sensitive detection of serum cystatin C.

Science.gov (United States)

Mi, Li; Wang, Pingyan; Yan, Junrong; Qian, Jing; Lu, Jusheng; Yu, Jiachao; Wang, Yuzhen; Liu, Hong; Zhu, Min; Wan, Yakun; Liu, Songqin

2016-01-01

Cystatin C (CysC) is a sensitive marker for the estimation of the glomerular filtration rate and the clinical diagnosis of different diseases. In this paper, CysC-specific nanobodies (Nbs) were isolated from a phage display nanobody library. A simple and sensitive photoelectrochemical immunosensor based on TiO2 nanotube arrays (TNAs) was proposed for the sensitive detection of CysC. The TiO2 nanotube arrays deposited by electrochemical anodization displayed a high and stable photocurrent response under irradiation. After coupling CysC-specific nanobody to TNA (Nb/TNA), the proposed immunosensor for CysC can be utilized for tracking the photocurrent change of Nb/TNA caused by immunoreactions between CysC and the immobilized CysC-specific Nb. This allowed for the determination of CysC with a calibration range from 0.72 pM to 7.19 nM. The variation of the photocurrent was in a linear relationship with the logarithm of the CysC concentration in the range of 0.72 pM-3.6 nM. The immunosensor had a correlation coefficient of 0.97 and a detection limit of 0.14 pM at a signal-to-noise ratio of 3. The proposed immunosensor showed satisfactory intra- and inter-assay accuracy, high selectivity and good stability. As a result, this proposed strategy would offer a novel and simple approach for the detection of immunoreactions, provide new insights in popularizing the diagnosis of CysC, and extend the application of TiO2 nanotubes. Copyright © 2015 Elsevier B.V. All rights reserved.

The NADPH thioredoxin reductase C functions as an electron donor to 2-Cys peroxiredoxin in a thermophilic cyanobacterium Thermosynechococcus elongatus BP-1

International Nuclear Information System (INIS)

Sueoka, Keigo; Yamazaki, Teruaki; Hiyama, Tetsuo; Nakamoto, Hitoshi

2009-01-01

An NADPH thioredoxin reductase C was co-purified with a 2-Cys peroxiredoxin by the combination of anion exchange chromatography and electroelution from gel slices after native PAGE from a thermophilic cyanobacterium Thermosynechococcus elongatus as an NAD(P)H oxidase complex induced by oxidative stress. The result provided a strong evidence that the NADPH thioredoxin reductase C interacts with the 2-Cys peroxiredoxin in vivo. An in vitro reconstitution assay with purified recombinant proteins revealed that both proteins were essential for an NADPH-dependent reduction of H 2 O 2 . These results suggest that the reductase transfers the reducing power from NADPH to the peroxiredoxin, which reduces peroxides in the cyanobacterium under oxidative stress. In contrast with other NADPH thioredoxin reductases, the NADPH thioredoxin reductase C contains a thioredoxin-like domain in addition to an NADPH thioredoxin reductase domain in the same polypeptide. Each domain contains a conserved CXYC motif. A point mutation at the CXYC motif in the NADPH thioredoxin reductase domain resulted in loss of the NADPH oxidation activity, while a mutation at the CXYC motif in the thioredoxin-like domain did not affect the electron transfer, indicating that this motif is not essential in the electron transport from NADPH to the 2-Cys peroxiredoxin.

Liquidus projection of the Nb-Cr-Al system near the Al3(Nb,Cr) + Cr(Al,Nb) eutectic region

International Nuclear Information System (INIS)

Souza, S.A.; Ferrandini, P.L.; Nunes, C.A.; Coelho, A.A.; Caram, R.

2006-01-01

The system Nb-Cr-Al was investigated in the region near the Al 3 (Nb,Cr) + Cr(Al,Nb) eutectic and the liquidus projection of that region was determined based on the microstructural characterization of arc melted alloys. The characterization utilized scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), differential thermal analysis (DTA) and X-ray diffraction (XRD). The results allowed one to determine three primary solidification liquidus surfaces ((Cr,Al) 2 Nb, Cr(Al,Nb) and Al 3 (Nb,Cr)), that are originated from the binary systems Cr-Nb, Cr-Al and Al-Nb. It is proposed the occurrence of the invariant reaction L + (Cr,Al) 2 Nb ↔ Al 3 (Nb,Cr) + Cr(Al,Nb) and of a point of minimum, which involves a three phase reaction, L ↔ Al 3 (Nb,Cr) + Cr(Al,Nb). All alloys studied showed formation of the Al 3 (Nb,Cr) + Cr(Al,Nb) eutectic as the last solidification step with Al(Nb)Cr 2 precipitating from Cr(Al,Nb)

Determination of Proton Relaxivities of Mn(II, Cu(II and Cr(III added to Solutions of Serum Proteins

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Ali Yilmaz

2009-04-01

Full Text Available Relaxometric studies are still of scientific interest due to their use in medicine and biology. In this study, proton T1 and T2 relaxivities of Mn(II, Cu(II and Cr(III in water were determined in the presence and absence of various proteins (albumin, α-globulin, γ-globulin, lysozyme, fibrinogen. The 1/T1 and 1/T2 in all solutions are linearly proportional to the concentration of the paramagnetic ions. Mn(II has the great influence to alter relaxations in all protein solutions, while Cu(II and Cr(III have a poor influence on the relaxations. In addition, Mn(II and Cu(II are bound to each protein, but Cr(III is not bound to any protein.

Combining Cystatin C and Creatinine Yields a Reliable Glomerular Filtration Rate Estimation in Older Adults in Contrast to β-Trace Protein and β2-Microglobulin.

Science.gov (United States)

Werner, Karin; Pihlsgård, Mats; Elmståhl, Sölve; Legrand, Helen; Nyman, Ulf; Christensson, Anders

2017-01-01

The glomerular filtration rate (GFR) is the most important measure of kidney function and chronic kidney disease (CKD). This study aims to validate commonly used equations for estimated GFR (eGFR) based on creatinine (cr), cystatin C (cys), β-trace protein (BTP), and β2-microglobulin (B2M) in older adults. We conducted a validation study with 126 participants aged between 72 and 98 with a mean measured GFR (mGFR) by iohexol clearance of 54 mL/min/1.73 m2. The eGFR equations (CKD-Epidemiology collaboration [CKD-EPI], Berlin Initiative Study [BIS], Full Age Spectrum [FAS], Modification of Diet in Renal Disease [MDRD]cr, Caucasian-Asian-Pediatric-Adult [CAPA]cys, Lund-Malmö Revised [LM-REV]cr, and MEAN-LM-CAPAcr-cys), were assessed in terms of bias (median difference: eGFR-mGFR), precision (interquartile range of the differences), and accuracy (P30: percentage of estimates ±30% of mGFR). The equations were compared to a benchmark equation: CKD-EPIcr-cys. All cystatin C-based equations underestimated the GFR compared to mGFR, whereas bias was mixed for the equations based only on creatinine. Accuracy was the highest for CKD-EPIcr-cys (98%) and lowest for MDRD (82%). Below mGFR 45 mL/min/1.73 m2 only equations incorporating cystatin C reached P30 accuracy >90%. CKD-EPIcr-cys was not significantly more accurate than the other cystatin C-based equations. In contrast, CKD-EPIcr-cys was significantly more accurate than all creatinine-based equations except LM-REVcr. This study confirms that it is reasonable to use equations incorporating cystatin C and creatinine in older patients across a wide spectrum of GFR. However, the results call into question the use of creatinine alone below mGFR 45 mL/min/1.73 m2. B2M and BTP do not demonstrate additional value in eGFR determination in older adults. © 2017 S. Karger AG, Basel.

A recurrent, non-penetrant sequence variant, p.Arg266Cys in Growth/Differentiation Factor 3 (GDF3 in a female with unilateral anophthalmia and skeletal anomalies

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Tanya Bardakjian

2017-09-01

Conclusions and importance: Although transfection studies with the p.Arg266Cys mutation have shown that this amino acid substitution is likely to impair function, non-penetrance for the ocular defects was apparent in this family and has been observed in other families with sequence variants in GDF3. We conclude p.Arg266Cys and other GDF3 mutations can be non-penetrant, making pathogenicity more difficult to establish when sequence variants in this gene are present in patients with structural eye defects.

The Structure of Plasmodium falciparum Blood-Stage 6-Cys Protein Pf41 Reveals an Unexpected Intra-Domain Insertion Required for Pf12 Coordination.

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Michelle L Parker

Full Text Available Plasmodium falciparum is an apicomplexan parasite and the etiological agent of severe human malaria. The complex P. falciparum life cycle is supported by a diverse repertoire of surface proteins including the family of 6-Cys s48/45 antigens. Of these, Pf41 is localized to the surface of the blood-stage merozoite through its interaction with the glycophosphatidylinositol-anchored Pf12. Our recent structural characterization of Pf12 revealed two juxtaposed 6-Cys domains (D1 and D2. Pf41, however, contains an additional segment of 120 residues predicted to form a large spacer separating its two 6-Cys domains. To gain insight into the assembly mechanism and overall architecture of the Pf12-Pf41 complex, we first determined the 2.45 Å resolution crystal structure of Pf41 using zinc single-wavelength anomalous dispersion. Structural analysis revealed an unexpected domain organization where the Pf41 6-Cys domains are, in fact, intimately associated and the additional residues instead map predominately to an inserted domain-like region (ID located between two β-strands in D1. Notably, the ID is largely proteolyzed in the final structure suggesting inherent flexibility. To assess the contribution of the ID to complex formation, we engineered a form of Pf41 where the ID was replaced by a short glycine-serine linker and showed by isothermal titration calorimetry that binding to Pf12 was abrogated. Finally, protease protection assays showed that the proteolytic susceptibility of the ID was significantly reduced in the complex, consistent with the Pf41 ID directly engaging Pf12. Collectively, these data establish the architectural organization of Pf41 and define an essential role for the Pf41 ID in promoting assembly of the Pf12-Pf41 heterodimeric complex.

Capturing Labile Sulfenamide and Sulfinamide Serum Albumin Adducts of Carcinogenic Arylamines by Chemical Oxidation

Science.gov (United States)

Peng, Lijuan; Turesky, Robert J.

2013-01-01

Aromatic amines and heterocyclic aromatic amines (HAAs) are a class of structurally related carcinogens that are formed during the combustion of tobacco or during the high temperature cooking of meats. These procarcinogens undergo metabolic activation by N-oxidation of the exocyclic amine group to produce N-hydroxylated metabolites, which are critical intermediates implicated in toxicity and DNA damage. The arylhydroxylamines and their oxidized arylnitroso derivatives can also react with cysteine (Cys) residues of glutathione or proteins to form, respectively, sulfenamide and sulfinamide adducts. However, sulfur-nitrogen linked adducted proteins are often difficult to detect because they are unstable and undergo hydrolysis during proteolytic digestion. Synthetic N-oxidized intermediates of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a carcinogenic HAA produced in cooked meats, and 4-aminobiphenyl, a carcinogenic aromatic amine present in tobacco smoke were reacted with human serum albumin (SA) and formed labile sulfenamide or sulfinamide adducts at the Cys34 residue. Oxidation of the carcinogen-modified SA with m-chloroperoxybenzoic acid (m-CPBA) produced the arylsulfonamide adducts, which were stable to heat and the chemical reduction conditions employed to denature SA. The sulfonamide adducts of PhIP and 4-ABP were identified, by liquid chromatography/mass spectrometry, in proteolytic digests of denatured SA. Thus, selective oxidation of arylamine-modified SA produces stable arylsulfonamide-SA adducts, which may serve as biomarkers of these tobacco and dietary carcinogens. PMID:23240913

Calcium and magnesium ions modulate the oligomeric state and function of mitochondrial 2-Cys peroxiredoxins in Leishmania parasites.

Science.gov (United States)

Morais, Mariana A B; Giuseppe, Priscila O; Souza, Tatiana A C B; Castro, Helena; Honorato, Rodrigo V; Oliveira, Paulo S L; Netto, Luis E S; Tomas, Ana M; Murakami, Mario T

2017-04-28

Leishmania parasites have evolved a number of strategies to cope with the harsh environmental changes during mammalian infection. One of these mechanisms involves the functional gain that allows mitochondrial 2-Cys peroxiredoxins to act as molecular chaperones when forming decamers. This function is critical for parasite infectivity in mammals, and its activation has been considered to be controlled exclusively by the enzyme redox state under physiological conditions. Herein, we have revealed that magnesium and calcium ions play a major role in modulating the ability of these enzymes to act as molecular chaperones, surpassing the redox effect. These ions are directly involved in mitochondrial metabolism and participate in a novel mechanism to stabilize the decameric form of 2-Cys peroxiredoxins in Leishmania mitochondria. Moreover, we have demonstrated that a constitutively dimeric Prx1m mutant impairs the survival of Leishmania under heat stress, supporting the central role of the chaperone function of Prx1m for Leishmania parasites during the transition from insect to mammalian hosts. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

[New topics regarding equations for GFR estimation based on serum creatinine and cystatin C].

Science.gov (United States)

Horio, Masaru

2014-02-01

Japanese GFR equations and CKD-EPI equations based on standardized serum creatinine and standardized cystatin C are recommended in recent Japanese CKD guides and KDIGO guidelines for CKD management, respectively. CKD-EPIcreat overestimates GFR in Japanese subjects, probably due to the difference in muscle mass between Japanese and Caucasians. Unlike CKD-EPIcreat, CKD-EPIcys performs well in Japanese subjects, indicating the advantages of using cystatin C as a GFR marker. KDIGO guidelines suggest measuring eGFRcys in adults with eGFRcreat of 45-59 ml/min/1.73 m2 who do not have markers of kidney damage if confirmation of CKD is required. Creatinine is excreted by glomerular filtration, but also secreted by the tubules. Alteration of the tubular secretion of creatinine may influence the performance of GFR equations based on serum creatinine. Multivariate analysis showed that GFR and serum albumin levels were independent parameters affecting the fractional excretion of creatinine (FE-Cr). Alteration of FE-Cr according to the serum albumin levels may be one of the reasons for the bias of GFR equations based on serum creatinine. Low GFR is a risk factor for all-cause and cardiovascular mortality in a general population. However, the relationship between eGFR and the hazard risk of events is different depending on whether cystatin C or creatinine is used to calculate eGFR. The association between eGFRcys and the hazard risk is much stronger compared with eGFRcreat. Cystatin C may be a useful alternative to creatinine for detecting a high risk of complications in a general population and subjects with CKD.

A highly sensitive and selective detection of Cr(VI) and ascorbic acid based on nitrogen-doped carbon dots.

Science.gov (United States)

Zhang, Yuhua; Fang, Xian; Zhao, Hong; Li, Zengxi

2018-05-01

A highly sensitive and selective detection of hexavalent chromium (Cr(VI)) and ascorbic acid (AA) was proposed using nitrogen-doped carbon dots (N-CDs). In the absence of AA, the quantitative detection of Cr(VI) was realized through Cr(VI) acting as a quencher to quench the fluorescence of N-CDs by inner filter effect (IFE) and static quenching effect. Under the optimal conditions, the linear range for Cr(VI) detection was from 0.01 to 250μM with a detection limit of 5nM (S/N = 3). In the presence of AA, the fluorescence intensity could be rapidly enhanced compared with the fluorescence of N-CDs/Cr(VI) system since Cr(VI) can be reduced into trivalent chromium (Cr(III)) by AA. And a wide linear range for AA detection was obtained from 1 to 750μM. The detection limit was 0.3μM (S/N = 3). More importantly, this method can be successfully applied to the detection of Cr(VI) in real water samples, and AA in vitamins C tablets and human serum sample. Copyright © 2018 Elsevier B.V. All rights reserved.

Cr(III) reactivity and foot dermatitis in Cr(VI) positive patients

DEFF Research Database (Denmark)

Hansen, Malene Barré; Menné, Torkil; Johansen, Jeanne Duus

2006-01-01

Chromium allergy has become synonymous with Cr(VI) allergy. However, real exposure to chromium from leather products may include both Cr(III) and Cr(VI). In this study, we investigate the reactivity to both Cr(VI) and Cr(III) in consecutive patients to analyse the relation between foot eczema/leather...... to Cr(III). The increased risk was not due to a higher degree of sensitivity to Cr(VI). Leather was reported most frequently as the suspected cause of chromium dermatitis (54%). However, Cr(VI) allergics having foot eczema and positive or doubtful Cr(III) reactions often had positive reactions to other...

Application of double-spike isotope dilution for the accurate determination of Cr(III), Cr(VI) and total Cr in yeast.

Science.gov (United States)

Yang, Lu; Ciceri, Elena; Mester, Zoltán; Sturgeon, Ralph E

2006-11-01

A method is presented for the simultaneous determination of Cr(III) and Cr(VI) in yeast using species-specific double-spike isotope dilution (SSDSID) with anion-exchange liquid chromatography (LC) separation and sector field inductively coupled plasma mass spectrometric (SF-ICP-MS) detection. Total Cr is quantitated using ID SF-ICP-MS. Samples were digested on a hot plate at 95+/-2 degrees C for 6 h in an alkaline solution of 0.5 M NaOH and 0.28 M Na2CO3 for the determination of Cr(III) and Cr(VI), whereas microwave-assisted decomposition with HNO3 and H2O2 was used for the determination of total Cr. Concentrations of 2,014+/-16, 1,952+/-103 and 76+/-48 mg kg-1 (one standard deviation, n=4, 3, 3), respectively were obtained for total Cr, Cr(III) and Cr(VI) in the yeast sample. Significant oxidation of Cr(III) to Cr(VI) (24.2+/-7.6% Cr(III) oxidized, n=3) and reduction of Cr(VI) to Cr(III) (37.6+/-6.5% Cr(VI) reduced, n=3) occurred during alkaline extraction and subsequent chromatographic separation at pH 7. Despite this significant bidirectional redox transformation, quantitative recoveries for both Cr(III) and Cr(VI) were achieved using the SSDSID method. In addition, mass balance between total Cr and the sum of Cr(III) and Cr(VI) concentrations was achieved. Method detection limits of 0.3, 2 and 30 mg kg-1 were obtained for total Cr, Cr(VI) and Cr(III), respectively, based on a 0.2-g sub-sample.

ERCC1 Cys8092Ala and XRCC1 Arg399Gln polymorphisms predict progression-free survival after curative radiotherapy for nasopharyngeal carcinoma.

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Hekun Jin

Full Text Available BACKGROUND: Single nucleotide polymorphisms (SNPs in DNA repair genes can alter gene expression and activity and affect response to cancer treatment and, correspondingly, survival. The present study was designed to evaluate the utility of the XRCC1 Arg399Gln and ERCC1 Cys8092Ala SNPs, measured in pretreatment biopsy samples, as predictors of response to radiotherapy in patients with non-metastatic nasopharyngeal carcinoma (NPC. MATERIALS AND METHODS: The study included 75 consecutive patients with stage II-IVA-B NPC. XRCC1 Arg399Glu and ERCC1 Cys8092Ala SNPs were identified from paraffin-embedded biopsy specimens via Sanger sequencing. Expression of p53 and pAkt protein was analyzed by immunohistochemical staining. Potential relationships between genetic polymorphisms and progression-free survival (PFS were analyzed by using a Cox proportional hazards model, the Kaplan-Meier method, and the log-rank test. RESULTS: Multivariate analysis showed that carriers of the ERCC1 8092 Ala/Ala genotype [hazard ratio (HR 1.882; 95% confidence interval (CI 1.031-3.438; P = 0.039] and heavy smokers (≥20 pack-years carrying the XRCC1 Arg/Arg genotype (HR 2.019; 95% CI 1.010-4.036; P = 0.047 had significantly lower PFS rates. Moreover, combined positive expression of p53 and pAkt led to significantly increased PFS in subgroups carrying the XRCC1 Gln allele (HR 7.057; 95% CI 2.073-24.021; P = 0.002 or the ERCC1 Cys allele (HR 2.568; 95% CI 1.056-6.248; P = 0.038. CONCLUSIONS: The ERCC1 Cys8092Ala polymorphism is an independent predictor of response to radiotherapy for NPC, and the XRCC1 Arg399Glu mutation combined with smoking status seems to predict PFS as well. Our results further suggest a possible correlation between these genetic polymorphisms and p53 protein status on survival.

Correlation between bulk- and surface chemistry of Cr-tanned leather and the release of Cr(III) and Cr(VI)

Energy Technology Data Exchange (ETDEWEB)

Hedberg, Yolanda S., E-mail: yolanda@kth.se [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Division of Surface and Corrosion Science, SE-10044 Stockholm (Sweden); Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-17177 Stockholm (Sweden); Lidén, Carola, E-mail: carola.liden@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-17177 Stockholm (Sweden); Odnevall Wallinder, Inger, E-mail: ingero@kth.se [KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, Division of Surface and Corrosion Science, SE-10044 Stockholm (Sweden)

2014-09-15

Graphical abstract: - Highlights: • Released reducing/complexing leather-specific species can reduce released Cr(VI). • No co-released species enable the formation of Cr(VI) in solution. • The major Cr species released from leather in phosphate buffer was Cr(III) (>82%). • No Cr(VI) was released into artificial sweat. - Abstract: About 1–3% of the adult general population in Europe is allergic to chromium (Cr). The assessment of the potential release of Cr(III) and Cr(VI) from leather is hence important from a human health and environmental risk perspective. The Cr(VI) content in leather was recently restricted in the European Union. The aim of this study was to assess possible correlations between the bulk and surface chemistry of leather, released Cr(III) and Cr(VI), and capacities of co-released leather specific species to reduce and complex released Cr. Four differently tanned leathers were characterized by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and the diphenylcarbazide colorimetric method. Their characteristics were compared with results on Cr(III) and Cr(VI) release into artificial sweat (ASW, pH < 6.5) and phosphate buffer (PB, pH 7.5–8.0), measured by means of spectrophotometry and atomic absorption spectroscopy. Co-released leather-specific species were shown to reduce Cr(VI), both in ASW and in PB. Their reduction capacities correlated with findings of the surface content of Cr and of released Cr. Leather samples without this capacity, and with less aromatic surface groups visible by ATR-FTIR, revealed Cr(VI) both at the surface and in solution (PB)

Revisitation of FRET methods to measure intraprotein distances in Human Serum Albumin

Energy Technology Data Exchange (ETDEWEB)

Santini, S.; Bizzarri, A.R.; Cannistraro, S., E-mail: cannistr@unitus.it

2016-11-15

We revisited the FRET methods to measure the intraprotein distance between Trp-214 (used as donor) of Human Serum Albumin and its Cys-34, labelled with 1.5-Iaedans (used as acceptor). Variation of Trp fluorescence emission in terms of both intensity and lifetime, as well the enhancement of the acceptor fluorescence emission upon Trp excitation, have been monitored. A careful statistical analysis of the fluorescence results from ten independently prepared samples, combined with suitable spectral corrections, provided reproducible distances estimations by each one of the three methods. Even if monitoring of the donor lifetime variation in the presence of the acceptor reproduces at the best the crystallographic data, by allowing even sub-nanometre distance variations to be appreciated, we suggest that a comparative analysis of all the three methods, applied with statistical significance, should be preferred to achieve a better reliability of the FRET technique.

Correlation between serum VEGF level and CT perfusion imaging in patients with primary liver cancer pre-and post TACE

International Nuclear Information System (INIS)

Jia Zhongzhi; Huang Yuanquan; Feng Yaoliang; Shi Haibin

2010-01-01

Objective: To investigate the correlation between serum vascular endothelial growth factor(VEGF) level and CT perfusion parameters in patients with primary liver cancer (PLC) pre-and post-transcatheter arterial chemoembolization (TACE) treatment. Methods: Serum VEGF level was measured and CT perfusion imaging was performed 1 day before and 6 ∼ 8, 32 ∼ 40 days after TACE in 18 patients with PLC. Before and after TACE, the serum VEGF level, the tumor's artery liver perfusion (ALP), the portal vein perfusion (PVP) and the hepatic artery perfusion index (HPI) were measured pre-and post-TACE. The pre-TACE and post-TACE results were compared and statistically analyzed. Results: Based on the therapeutic results, the patients were divided into complete response (CR) group and partial response or stable disease(PR+SD) group. Although no significant difference in serum VEGF level, tumor's ALP, PVP and HPI existed between two groups pre-TACE, there was significant difference in ALP, HPI 6-8 days after TACE (P<0.05). Significant difference in serum VEGF level also existed in CR group (P<0.05), but not in (PR+SD) group, at (32-40) days post-TACE (P=0.221). The serum VEGF level carried a positive correlation with the tumor's ALP and HPI. Conclusion: The serum VEGF level can indirectly reflect the neovascularization of the tumor, while the CTPI can directly and quantitatively reflect the hemodynamic changes of the tumor post-TACE. Moreover, a positive correlation exists between serum VEGF level and ALP, HPI. Therefore, the determination of serum VEGF level together with CTPI is very useful in both evaluating TACE efficacy and making therapeutic schedule. (authors)

Comparative radioprotective studies of chlorpromazine and cysteamine on rat bone development; Effect on serum and bone proteins

Energy Technology Data Exchange (ETDEWEB)

Abdeen, A M; Ibrahim, H A; Badawy, M; Elkholy, W M.E.

1986-01-01

Experiments were planned to study the radioprotective effect of chlorpromazine (CPZ) and Cysteamine (Cys), when injected separately or combined before irradiation, on some factors affecting the development of rat bone. The results obtained can be summarized as follows: (1) The body weight decreased due to gamma-irradiation. (2) The mortality rate increased after irradiation, but diminished by single or double chemical injection before irradiation. (3) The serum total protein; albumin, globulin contents and A/G ratio were significantly increased, 6 hrs. After irradiation, then declined afterwards. (4) Histochemically, a decrease in bone protein content was demonstrates after irradiation. The above irradiation effects were suppressed by injection of the radioprotective substances. Their effect seems to be cumulative. 4 fig.,3 tab.

Correlation between bulk- and surface chemistry of Cr-tanned leather and the release of Cr(III) and Cr(VI).

Science.gov (United States)

Hedberg, Yolanda S; Lidén, Carola; Odnevall Wallinder, Inger

2014-09-15

About 1-3% of the adult general population in Europe is allergic to chromium (Cr). The assessment of the potential release of Cr(III) and Cr(VI) from leather is hence important from a human health and environmental risk perspective. The Cr(VI) content in leather was recently restricted in the European Union. The aim of this study was to assess possible correlations between the bulk and surface chemistry of leather, released Cr(III) and Cr(VI), and capacities of co-released leather specific species to reduce and complex released Cr. Four differently tanned leathers were characterized by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and the diphenylcarbazide colorimetric method. Their characteristics were compared with results on Cr(III) and Cr(VI) release into artificial sweat (ASW, pHleather-specific species were shown to reduce Cr(VI), both in ASW and in PB. Their reduction capacities correlated with findings of the surface content of Cr and of released Cr. Leather samples without this capacity, and with less aromatic surface groups visible by ATR-FTIR, revealed Cr(VI) both at the surface and in solution (PB). Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Serum Creatinine in Patients with Advanced Liver Disease Is of Limited Value for Identification of Moderate Renal Dysfunction: Are the Equations for Estimating Renal Function Better?

Directory of Open Access Journals (Sweden)

Jillian MacAulay

2006-01-01

Full Text Available BACKGROUND: The Cockcroft-Gault formula (CGF is used to estimate the glomerular filtration rate (GFR based on serum creatinine (Cr levels, age and sex. A new formula developed by the Modification of Diet in Renal Disease (MDRD Study Group, based on the patient’s Cr levels, age, sex, race and serum urea nitrogen and serum albumin levels, has shown to be more accurate. However, the best formula to identify patients with advanced liver disease (ALD and moderate renal dysfunction (GFR 60 mL/min/1.73 m2 or less is not known. The aim of the present study was to compare calculations of GFR, using published formulas (excluding those requiring urine collections with standard radionuclide measurement of GFR in patients with ALD.

Value of impulse oscillometry in evaluating the illness in children with asthma and analysis of its correlation with serum indicators

Directory of Open Access Journals (Sweden)

Cui-Fen Bai

2016-05-01

Full Text Available Objective: To Value of impulse oscillometry in evaluating the illness in children with asthma and its correlation with serum indicators. Methods: Children with asthma attack, children with asthma remission and healthy children were selected for study, impulse oscillometry was conducted to obtain related parameters, and serum and peripheral blood were collected to detect related indicators. Results: Zrs, R5, R20, R5-R20, absolute value of X5 and Fres of asthma attack group and asthma remission group were higher than those of control group, eosinophil, YKL-40, Hes-1, Cyr61, Eotaxin, IgE, IgG4, LT-B4, LT-C4, LT-D4 and Cys-LT contents in peripheral blood were higher than those of control group, positive proportion of Th2, Th17, cTfh and Th19 in peripheral blood were higher than those of control group, and positive proportion of Th1 and Treg in peripheral blood were lower than those of control group; the changes of above indicators of asthma attack group were more significant than those of asthma remission group; Zrs, R5, R20, R5-R20, absolute value of X5 and Fres were positively correlated with eosinophil, YKL-40, Hes-1, Cyr61, Eotaxin, IgE, IgG4, LT-B4, LT-C4, LTD4 and Cys-LT contents in peripheral blood as well as positive proportion of Th2, Th17, cTfh and Th19 in peripheral blood, and negatively correlated with positive proportion of Th1 and Treg in peripheral blood. Conclusion: Impulse oscillometry detection can provide evidence for diagnosis of bronchial asthma and judgment of its illness, and IOS-related parameters can judge the abnormal degree of inflammatory response and immune response.

Dynamics of Pseudomonas aeruginosa azurin and its Cys3Ser mutant at single crystal gold surfaces investigated by cyclic voltammetry and atomic force microscopy

DEFF Research Database (Denmark)

Friis, Esben P.; Andersen, Jens Enevold Thaulov; Madsen, Lars Lithen

1997-01-01

Cyclic voltammetry of Pseudomonas aeruginosa azurin on polycrystalline gold is reversible (E0=360mV vs she;50mM ammonium acetate) but the voltammetric signals decay with time constants of about 3x10-3 s-1. No signal is observed for monocrystalline Au(111). Cys3Ser azurin is electrochemically inac...... into the solution, recovering the free Au(111) surface. The cyclic voltammetry and AFM data are consistent with time dependent adsorption of the azurins on gold via the disulphide bridge (wild-type) or free thiol group (Cys3Ser mutant).......Cyclic voltammetry of Pseudomonas aeruginosa azurin on polycrystalline gold is reversible (E0=360mV vs she;50mM ammonium acetate) but the voltammetric signals decay with time constants of about 3x10-3 s-1. No signal is observed for monocrystalline Au(111). Cys3Ser azurin is electrochemically...... inactive on either type of gold electrode but shows a reversible although decaying peak (362mV, 50mM ammonium acetate; decay time constant ~ 2x10-3 s-1) on edge-plane pyrolytic graphite.Ex situ and in situ atomic force microscopy (AFM) of the azurins on Au(111) show initially arrays of protein structures...

Organic cattle products: Authenticating production origin by analysis of serum mineral content.

Science.gov (United States)

Rodríguez-Bermúdez, Ruth; Herrero-Latorre, Carlos; López-Alonso, Marta; Losada, David E; Iglesias, Roberto; Miranda, Marta

2018-10-30

An authentication procedure for differentiating between organic and non-organic cattle production on the basis of analysis of serum samples has been developed. For this purpose, the concentrations of fourteen mineral elements (As, Cd, Co, Cr, Cu, Fe, Hg, I, Mn, Mo, Ni, Pb, Se and Zn) in 522 serum samples from cows (341 from organic farms and 181 from non-organic farms), determined by inductively coupled plasma spectrometry, were used. The chemical information provided by serum analysis was employed to construct different pattern recognition classification models that predict the origin of each sample: organic or non-organic class. Among all classification procedures considered, the best results were obtained with the decision tree C5.0, Random Forest and AdaBoost neural networks, with hit levels close to 90% for both production types. The proposed method, involving analysis of serum samples, provided rapid, accurate in vivo classification of cattle according to organic and non-organic production type. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of Cr content on the SHS reaction of Cr-Ti-C system

International Nuclear Information System (INIS)

Zhang, W.N.; Wang, H.Y.; Wang, P.J.; Zhang, J.; He, L.; Jiang, Q.C.

2008-01-01

The effect of Cr content on the self-propagating high temperature synthesis (SHS) reaction of Cr-Ti-C system has been investigated in this research. The thermodynamics calculation indicates that the TiC possesses higher thermodynamic stability than the Cr 23 C 6 , Cr 7 C 3 and Cr 3 C 2 phases, and the formation of TiC is the most exothermic. Additionally, the adiabatic combustion temperature (T ad ) decreases with the increase of Cr content except for the phase transition regions. The XRD result shows that the type of products synthesized by SHS changes that a higher Cr content corresponds to higher chromium carbide. When Cr content is 10 wt.%, only solid solution (Ti,Cr)C ss is formed in the products. When Cr content increases to 20 wt.%, besides (Ti,Cr)C ss , the Cr 7 C 3 phase is also detected. With the Cr content further increasing to 30 and 40 wt.%, the products consist of (Ti,Cr)C ss , Cr 23 C 6 , Cr 7 C 3 and Cr, and therefore, much higher chromium carbide is synthesized. When Cr content reaches 50 wt.%, however, the Cr 7 C 3 disappears and the final products become (Ti,Cr)C ss , Cr 23 C 6 and Cr. Moreover, when Cr content increases from 10 to 20 wt.%, the lattice parameter of (Ti,Cr)C ss decreases, while it increases when the Cr content ranges from 20 to 50 wt.%. Furthermore, the microstructure shows that the TiC particulate size decreases from ∼8 to ∼2 μm with the increase of Cr content from 10 to 50 wt.%, and the morphology shape of TiC particulate becomes more and more spherical

Absence of cystatin C involvement in ventricular remodelling and heart failure.

Science.gov (United States)

Pérez-Calvo, J I; Castiella Muruzábal, T; Búcar Barjud, M; Josa Laorden, C; Sánchez Marteles, M; Lacambra Blasco, I; Asensio López, M C; Pascual Figal, D A

2016-03-01

Cystatin C (CysC) is a protease encoded by housekeeping genes. Although its prognostic value in heart failure (HF) is well known, it is debatable whether this value is due to the greater accuracy of CysC in calculating the glomerular filtration rate or to its involvement in pathological ventricular remodelling. The aim of this study was to determine whether CysC expression changes in the myocardium of foetuses of different ages and in the myocardium of adults with various cardiovascular diseases, as well as to analyse the correlation between its serum concentrations and cardiac structure and morphology in a patient group with HF. We analysed the correlations (Pearson's r and Spearman's test) between the serum CysC levels and echocardiographic parameters of 351 patients with HF. We also performed immunohistochemical staining for CysC, metalloproteinase-9 (MMP-9) and desmin in 9 cardiac tissue samples from autopsies of 4 foetuses of different gestational ages and 5 healthy adults or adults with cardiovascular disease. For the patients with HF, there was no correlation between the CysC concentrations and the cardiac parameters measured by 2D echocardiography. The immunohistochemistry showed a weak background staining for CysC in all samples, regardless of age and the presence or absence of cardiovascular diseases. Our results suggest that CysC does not have a significant role in the pathological remodelling of the left ventricle in HF. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.

Prediction of renal function (GFR) from cystatin C and creatinine in children: Body cell mass increases accuracy of the estimate

DEFF Research Database (Denmark)

Andersen, Trine Borup; Jødal, Lars; Bøgsted, Martin

) aged 2-14 years (mean 8.8 years). GFR was 14-147 mL/min/1.73m2 (mean 97 mL/min/1.73m2). BCM was estimated using bioimpedance spectroscopy (Xitron Hydra 4200). Log-transformed data on BCM/CysC, serum creatinine (SCr), body-surface-area (BSA), height x BSA/SCr, serum CysC, weight, sex, age, height, serum....... The present equation also had the highest R2 and the narrowest 95% limits of agreement. CONCLUSION: The new equation predicts GFR with higher accuracy than other equations. Endogenous methods are, however, still not accurate enough to replace exogenous markers when GFR must be determined with high accuracy...

GFR prediction from cystatin C and creatinine in children: body cell mass increases accuracy of the estimate

DEFF Research Database (Denmark)

Andersen, Trine Borup; Jødal, Lars; Bøgsted, Martin

) aged 2-14 years (mean 8.8 years). GFR was 14-147 mL/min/1.73m2 (mean 97 mL/min/1.73m2). BCM was estimated using bioimpedance spectroscopy (Xitron Hydra 4200). Log-transformed data on BCM/CysC, serum creatinine (SCr), body-surface-area (BSA), height x BSA/SCr, serum CysC, weight, sex, age, height, serum....... The present equation also had the highest R2 and the narrowest 95% limits of agreement. CONCLUSION: The new equation predicts GFR with higher accuracy than other equations. Endogenous methods are, however, still not accurate enough to replace exogenous markers when GFR must be determined with high accuracy...

Symmetrical dimer of the human dopamine transporter revealed by cross-linking Cys-306 at the extracellular end of the sixth transmembrane segment.

Science.gov (United States)

Hastrup, H; Karlin, A; Javitch, J A

2001-08-28

There is evidence both for and against Na(+)- and Cl(-)-dependent neurotransmitter transporters forming oligomers. We found that cross-linking the human dopamine transporter (DAT), which is heterologously expressed in human embryonic kidney 293 cells, either with copper phenanthroline (CuP) or the bifunctional reagent bis-(2-methanethiosulfonatoethyl)amine hydrochloride (bis-EA) increased the apparent molecular mass determined with nonreducing SDS/PAGE from approximately 85 to approximately 195 kDa. After cross-linking, but not before, coexpressed, differentially epitope-tagged DAT molecules, solubilized in Triton X-100, were coimmunoprecipitated. Thus, the 195-kDa complex was a homodimer. Cross-linking of DAT did not affect tyramine uptake. Replacement of Cys-306 with Ala prevented cross-linking. Replacement of all of the non-disulfide-bonded cysteines in the extracellular and membrane domains, except for Cys-306, did not prevent cross-linking. We conclude that the cross-link is between Cys-306 at the extracellular end of TM6 in each of the two DATs. The motif GVXXGVXXA occurs at the intracellular end of TM6 in DAT and is found in a number of other neurotransmitter transporters. This sequence was originally found at the dimerization interface in glycophorin A, and it promotes dimerization in model systems. Mutation of either glycine disrupted DAT expression and function. The intracellular end of TM6, like the extracellular end, is likely to be part of the dimerization interface.

Preliminary Microstructural and Microscratch Results of Ni-Cr-Fe and Cr3C2-NiCr Coatings on Magnesium Substrate

Science.gov (United States)

Istrate, B.; Munteanu, C.; Lupescu, S.; Benchea, M.; Vizureanu, P.

2017-06-01

Thermal coatings have a large scale application in aerospace and automotive field, as barriers improving wear mechanical characteristics and corrosion resistance. In present research, there have been used two types of coatings, Ni-Cr-Fe, respectively Cr3C2-NiCr which were deposited on magnesium based alloys (pure magnesium and Mg-30Y master alloy). There have been investigated the microstructural aspects through scanning electronic microscopy and XRD analysis and also a series of mechanical characteristics through microscratch and indentation determinations. The results revealed the formation of some adherent layers resistant to the penetration of the metallic indenter, the coatings did not suffer major damages. Microstructural analysis highlighted the formation of Cr3C2, Cr7C3, Cr3Ni2, Cr7Ni3, FeNi3, Cr-Ni phases. Also, the apparent coefficient of friction for Ni-Cr-Fe coatings presents superior values than Cr3C2-NiCr coatings.

História natural da hepatite crônica B Natural history of chronic hepatitis B

Directory of Open Access Journals (Sweden)

José Carlos Ferraz da Fonseca

2007-12-01

Full Text Available Estima-se que existam 350 milhões de portadores crônicos do VHB distribuídos ao redor do mundo. Três fases de infecção crônica pelo VHB são reconhecidas: fase de imunotolerância (HBsAg e HBeAg positivos, altos títulos de HBV-DNA, ALT normal e não evidência de doença hepática ativa; fase imunoativa ou de hepatite crônica B (HBsAg e HBeAg positivos, altos títulos de HBV-DNA, ALT elevada e evidência de doença hepática ativa; fase de portador inativo do VHB ou assintomático (HBsAg no soro sem o HBeAg , títulos do HBV-DNA An estimated 350 million people worldwide are chronically infected with hepatitis B virus (HBV. Three phases of chronic hepatitis B virus infection is are recognized: the immune tolerant phase (HBeAg-positive, high levels of serum HBV-DNA, normal ALT, and no evidence of active liver diseases, the immune clearance phase or chronic hepatitis phase (HBeAg-positive, high levels of serum HBV-DNA, elevated ALT, and active liver disease , and the inactive carrier state or asymptomatic phase (HBsAg-positive in serum without HBeAg, HBV-DNA levels than < 10(5 copies/mL, and normal ALT levels. Chronic hepatitis B is classified into 2 major forms: HBeAg-positive disease (wild-type HBV and HBeAg negative disease (pre-core/core promoter HBV variant. Both forms can lead to liver cirrhosis, hepatic decompensation and liver cancer. The purpose of this article is to review the principal aspects of natural history of chronic hepatitis B.

RIGScan CR: RIGScan CR49.

Science.gov (United States)

2004-01-01

RIGScan CR49, a 125I-labelled CR monoclonal antibody directed against the tumour-associated antigen TAG-72, is undergoing development with Neoprobe for the intraoperative detection of metastatic colorectal cancer. The Neoprobe's proprietary RIGS (radioimmunoguided surgery) technology combines an injectable radiolabelled cancer-targeting agent and hand-held radiation detection probe that emits an audible tone when located tissue has accumulated a significant amount of the radioactive agent. Neoprobe's RIGS technology also includes a patented surgical method providing surgeons with real-time information to locate tumour deposits that can not be detected by other conventional methods. The RIGS technology has been evaluated in late clinical studies for the detection of adenocarcinomas including primary colorectal, gastrointestinal, breast, ovarian, pancreatic, prostate and neuroendocrine/endocrine. Neoprobe signed an option agreement for its first-generation RIGScan compound, RIGScan CR, with OncoSurg Inc. (formerly NuRigs Ltd). The second-generation humanised RIGScan CR agent was also optionally licensed to OncoSurg Inc. In 1997, Neoprobe filed for approval with the US FDA and the EMEA for RIGScan CR for the intraoperative detection of metastatic colorectal cancer. Both regulatory agencies have requested additional clinical data. On 19 April 2004, Neoprobe announced that it had met with the US FDA to discuss its position on submitting additional clinical information in response to the FDA's questions regarding the Biologic Licence Application (BLA) for RIGScan CR49. The company provided the FDA with new information related to a survival differential for patients whose colorectal cancer was evaluated with RIGScan CR49. The information was not available at the time of the BLA's submission in 1997. The agency indicated that it would consider accepting survival data from one of the two phase III trials, NEO2-14, but not from another trial NEO2-13, as supportive data for a

The thiol of human serum albumin: Acidity, microenvironment and mechanistic insights on its oxidation to sulfenic acid.

Science.gov (United States)

Bonanata, Jenner; Turell, Lucía; Antmann, Laura; Ferrer-Sueta, Gerardo; Botasini, Santiago; Méndez, Eduardo; Alvarez, Beatriz; Coitiño, E Laura

2017-07-01

Human serum albumin (HSA) has a single reduced cysteine residue, Cys34, whose acidity has been controversial. Three experimental approaches (pH-dependence of reactivity towards hydrogen peroxide, ultraviolet titration and infrared spectroscopy) are used to determine that the pK a value in delipidated HSA is 8.1±0.2 at 37°C and 0.1M ionic strength. Molecular dynamics simulations of HSA in the sub-microsecond timescale show that while sulfur exposure to solvent is limited and fluctuating in the thiol form, it increases in the thiolate, stabilized by a persistent hydrogen-bond (HB) network involving Tyr84 and bridging waters to Asp38 and Gln33 backbone. Insight into the mechanism of Cys34 oxidation by H 2 O 2 is provided by ONIOM(QM:MM) modeling including quantum water molecules. The reaction proceeds through a slightly asynchronous S N 2 transition state (TS) with calculated Δ ‡ G and Δ ‡ H barriers at 298K of respectively 59 and 54kJmol -1 (the latter within chemical accuracy from the experimental value). A post-TS proton transfer leads to HSA-SO - and water as products. The structured reaction site cages H 2 O 2 , which donates a strong HB to the thiolate. Loss of this HB before reaching the TS modulates Cys34 nucleophilicity and contributes to destabilize H 2 O 2 . The lack of reaction-site features required for differential stabilization of the TS (positive charges, H 2 O 2 HB strengthening) explains the striking difference in kinetic efficiency for the same reaction in other proteins (e.g. peroxiredoxins). The structured HB network surrounding HSA-SH with sequestered waters carries an entropic penalty on the barrier height. These studies contribute to deepen the understanding of the reactivity of HSA-SH, the most abundant thiol in human plasma, and in a wider perspective, provide clues on the key aspects that modulate thiol reactivity against H 2 O 2 . Copyright © 2017 Elsevier Inc. All rights reserved.

Clinical value of renal injury biomarkers in diagnosis of chronic kidney disease

Directory of Open Access Journals (Sweden)

Cheng-lu ZHANG

2011-12-01

Full Text Available Objective To investigate the levels of renal injury biomarkers in patients with chronic kidney disease(CKD and evaluate their clinical significances in diagnosis of CKD.Methods A total of 66 subjects(37 patients with CKD and 29 healthy individuals were involved in this study.Serum blood urea nitrogen(SBUN was determined by Glutamate dehydrogenase method;serum creatinine(SCr and urinary creatinine(UCr were detected by sarcosine oxidase method;serum uric acid(SUA was measured by uricase colorimetry;serum cystatin C(Cys C and urinary microalbumin(UmAlbwere analyzed by immunological transmission turbidimetry;urinary protein(U-PROwas measured by Coomassies Brilliant Blue(CBB assay.The UmAlb and U-PRO levels were expressed in units of mg/mmolUCr.Results The results of independent samples t test indicated that significant differences were found in SBUN,SCr,SUA,Cys C,UmAlb and U-PRO(P < 0.05 between patient group and healthy control group.The evaluation of diagnostic effects showed that the areas under the curve at ROC plot for SBUN,SCr,SUA,Cys C,UmAlb and U-PRO were 0.907,0.912,0.742,0.982,0.984 and 0.991,respectively.Conclusions U-PRO,UmAlb and Cys C are ideal biomarkers,SCr and SBUN come next,SUA is the weakest when the above biomarkers are applied to evaluate the renal injury and its severity of the patients with CKD.

Expression of salt-induced 2-Cys peroxiredoxin from Oryza sativa increases stress tolerance and fermentation capacity in genetically engineered yeast Saccharomyces cerevisiae.

Science.gov (United States)

Kim, Il-Sup; Kim, Young-Saeng; Yoon, Ho-Sung

2013-04-01

Peroxiredoxins (Prxs), also termed thioredoxin peroxidases (TPXs), are a family of thiol-specific antioxidant enzymes that are critically involved in cell defense and protect cells from oxidative damage. In this study, a putative chloroplastic 2-Cys thioredoxin peroxidase (OsTPX) was identified by proteome analysis from leaf tissue samples of rice (Oryza sativa) seedlings exposed to 0.1 M NaCl for 3 days. To investigate the relationship between the OsTPX gene and the stress response, OsTPX was cloned into the yeast expression vector p426GPD under the control of the glyceraldehyde-3-phosphate dehydrogenase (GPD1) promoter, and the construct was transformed into Saccharomyces cerevisiae cells. OsTPX expression was confirmed by semi-quantitative reverse transcription-polymerase chain reaction and western blot analyses. OsTPX contained two highly conserved cysteine residues (Cys114 and Cys236) and an active site region (FTFVCPT), and it is structurally very similar to human 2-Cys Prx. Heterologous OsTPX expression increased the ability of the transgenic yeast cells to adapt and recover from reactive oxygen species (ROS)-induced oxidative stresses, such as a reduction of cellular hydroperoxide levels in the presence of hydrogen peroxide and menadione, by improving redox homeostasis. OsTPX expression also conferred enhanced tolerance to tert-butylhydroperoxide, heat shock, and high ethanol concentrations. Furthermore, high OsTPX expression improved the fermentation capacity of the yeast during glucose-based batch fermentation at a high temperature (40 °C) and at the general cultivation temperature (30 °C). The alcohol yield in OsTPX-expressing transgenic yeast increased by approximately 29 % (0.14 g g(-1)) and 21 % (0.12 g g(-1)) during fermentation at 40 and 30 °C, respectively, compared to the wild-type yeast. Accordingly, OsTPX-expressing transgenic yeast showed prolonged cell survival during the environmental stresses produced during fermentation. These

Cr3+ and Cr4+ luminescence in glass ceramic silica

International Nuclear Information System (INIS)

Martines, Marco A.U.; Davolos, Marian R.; Jafelicci, Miguel Junior; Souza, Dione F. de; Nunes, Luiz A.O.

2008-01-01

This paper reports on the effect of glass ceramic silica matrix on [CrO 4 ] 4- and Cr 2 O 3 NIR and visible luminescence. Chromium-containing silica was obtained by precipitation from water-glass and chromium nitrate acid solution with thermal treatment at 1000 deg. C. From XRD results silica and silica-chromium samples are crystalline. The chromium emission spectrum presents two main broad bands: one in the NIR region (1.1-1.7μm) and other in the visible region (0.6-0.7μm) assigned to Cr 4+ and to Cr 3+ , respectively. This thermal treated glass ceramic silica-chromium sample stabilizes the [CrO 4 ] 4- where Cr 4+ substitutes for Si 4+ and also hexacoordinated Cr 3+ group probably as segregated phase in the system. It can be pointed out that luminescence spectroscopy is a powerful tool for detecting the two chromium optical centers in the glass ceramic silica

Palmitoylation at Cys574 is essential for MT1-MMP to promote cell migration

DEFF Research Database (Denmark)

Anilkumar, Narayanapanicker; Uekita, Takamasa; Couchman, John R

2005-01-01

of the palmitoylated cysteine relative to LLY573, a motif that interacts with mu2 subunit of adaptor protein 2, is critical for the cell motility-promoting activity of MT1-MMP and its clathrin-mediated internalization. Taken together, palmitoylation of MT1-MMP is one of the key posttranslational modifications......MT1-MMP is a type I transmembrane proteinase that promotes cell migration and invasion. Here, we report that MT1-MMP is palmitoylated at Cys574 in the cytoplasmic domain, and this lipid modification is critical for its promotion of cell migration and clathrin-mediated internalization...... that determines MT1-MMP-dependent cell migration....

The roles of complement receptors type 1 (CR1, CD35) and type 3 (CR3, CD11b/CD18) in the regulation of the immune complex-elicited respiratory burst of polymorphonuclear leukocytes in whole blood

DEFF Research Database (Denmark)

Nielsen, C H; Antonsen, S; Matthiesen, S H

1997-01-01

The binding of immune complexes (IC) to polymorphonuclear leukocytes (PMN) and the consequent respiratory burst (RB) were investigated in whole blood cell preparations suspended in 75% human serum, using flow cytometry. Blockade of the complement receptor (CR)1 receptor sites for C3b on whole blood...... cells using the monoclonal antibody (mAb) 3D9 resulted in a 1.9-fold increase in the IC-elicited PMN RB after 5 min of incubation, rising to 3.1-fold after 40 min. This enhancement was not due to increased IC deposition on PMN. Blockade of CR3 abrogated the mAb 3D9-induced rise in RB activity...

Kinetics of Cr(III) and Cr(VI) removal from water by two floating macrophytes.

Science.gov (United States)

Maine, M A; Hadad, H R; Sánchez, G; Caffaratti, S; Pedro, M C

2016-01-01

The aim of this work was to compare Cr(III) and Cr(VI) removal kinetics from water by Pistia stratiotes and Salvinia herzogii. The accumulation in plant tissues and the effects of both Cr forms on plant growth were also evaluated. Plants were exposed to 2 and 6 mg L(-1) of Cr(III) or Cr(VI) during 30 days. At the end of the experiment, Cr(VI) removal percentages were significantly lower than those obtained for Cr(III) for both macrophytes. Cr(III) removal kinetics involved a fast and a slow component. The fast component was primarily responsible for Cr(III) removal while Cr(VI) removal kinetics involved only a slow process. Cr accumulated principally in the roots. In the Cr(VI) treatments a higher translocation from roots to aerial parts than in Cr(III) treatments was observed. Both macrophytes demonstrated a high ability to remove Cr(III) but not Cr(VI). Cr(III) inhibited the growth at the highest studied concentration of both macrophytes while Cr(VI) caused senescence. These results have important implications in the use of constructed wetlands for secondary industrial wastewater treatment. Common primary treatments of effluents containing Cr(VI) consists in its reduction to Cr(III). Cr(III) concentrations in these effluents are normally below the highest studied concentrations in this work.

X-ray fluorescence analysis of Cr6+ component in mixtures of Cr2O3 and K2CrO4

International Nuclear Information System (INIS)

Tochio, Tatsunori; Sakakura, Shusuke; Oohashi, Hirofumi

2010-01-01

X-ray fluorescence analysis using Cr K α spectra was applied to the determination of the mixing ratio of Cr 6+ to (Cr 6+ + Cr 3+ ) in several mixtures of K 2 CrO 4 and Cr 2 O 3 . Because the powder of K 2 CrO 4 contained large particles that were more than 50 μm in diameter, it was ground between a pestle and a mortar for about 8 h. The coarse particles still remaining were removed by using a sieve with 325-mesh (44 μm) in order to reduce the difference in absorption effects between emissions from Cr 6+ and those from Cr 3+ . The mixing ratio, K 2 CrO 4 /(K 2 CrO 4 + Cr 2 O 3 ), of the five mixtures investigated is 0.50, 0.40, 0.20, 0.10, and 0.05 in weight, respectively. Each spectrum obtained was analyzed by decomposing it into two reference spectra, those of the two pure materials, K 2 CrO 4 and Cr 2 O 3 , with a constant background. The results for the mixtures containing K 2 CrO 4 of more than 20 wt% are that the relative deviation from the true value is less than ∼5%. On the other hand, when the content of K 2 CrO 4 decreases to less than 10 wt%, the relative deviation gets so large as 20 - 25%. The error coming from a peak separation of spectrum involved in our results were estimated by applying our method to five sets of data for each mixture computationally generated, taking into account the uncertainty in total counts of real measurements. (author)

X-ray fluorescence analysis of Cr(6+) component in mixtures of Cr(2)O(3) and K(2)CrO(4).

Science.gov (United States)

Tochio, Tatsunori; Sakakura, Shusuke; Oohashi, Hirofumi; Mizota, Hirohisa; Zou, Yanhui; Ito, Yoshiaki; Fukushima, Sei; Tanuma, Shigeo; Shoji, Takashi; Fujimura, Hajime; Yamashita, Michiru

2010-01-01

X-ray fluorescence analysis using Cr K(alpha) spectra was applied to the determination of the mixing ratio of Cr(6+) to (Cr(6+) + Cr(3+)) in several mixtures of K(2)CrO(4) and Cr(2)O(3). Because the powder of K(2)CrO(4) contained large particles that were more than 50 microm in diameter, it was ground between a pestle and a mortar for about 8 h. The coarse particles still remaining were removed by using a sieve with 325-mesh (44 microm) in order to reduce the difference in absorption effects between emissions from Cr(6+) and those from Cr(3+). The mixing ratio, K(2)CrO(4)/(K(2)CrO(4) + Cr(2)O(3)), of the five mixtures investigated is 0.50, 0.40, 0.20, 0.10, and 0.05 in weight, respectively. Each spectrum obtained was analyzed by decomposing it into two reference spectra, those of the two pure materials, K(2)CrO(4) and Cr(2)O(3), with a constant background. The results for the mixtures containing K(2)CrO(4) of more than 20 wt% are that the relative deviation from the true value is less than approximately 5%. On the other hand, when the content of K(2)CrO(4) decreases to less than 10 wt%, the relative deviation gets so large as 20 - 25%. The error coming from a peak separation of spectrum involved in our results were estimated by applying our method to five sets of data for each mixture computationally generated, taking into account the uncertainty in total counts of real measurements.

Bulk and surface properties of liquid Al-Cr and Cr-Ni alloys

International Nuclear Information System (INIS)

Novakovic, R

2011-01-01

The energetics of mixing and structural arrangement in liquid Al-Cr and Cr-Ni alloys has been analysed through the study of surface properties (surface tension and surface segregation), dynamic properties (chemical diffusion) and microscopic functions (concentration fluctuations in the long-wavelength limit and chemical short-range order parameter) in the framework of statistical mechanical theory in conjunction with quasi-lattice theory. The Al-Cr phase diagram exhibits the existence of different intermetallic compounds in the solid state, while that of Cr-Ni is a simple eutectic-type phase diagram at high temperatures and includes the low-temperature peritectoid reaction in the range near a CrNi 2 composition. Accordingly, the mixing behaviour in Al-Cr and Cr-Ni alloy melts was studied using the complex formation model in the weak interaction approximation and by postulating Al 8 Cr 5 and CrNi 2 chemical complexes, respectively, as energetically favoured.

Bulk and surface properties of liquid Al-Cr and Cr-Ni alloys.

Science.gov (United States)

Novakovic, R

2011-06-15

The energetics of mixing and structural arrangement in liquid Al-Cr and Cr-Ni alloys has been analysed through the study of surface properties (surface tension and surface segregation), dynamic properties (chemical diffusion) and microscopic functions (concentration fluctuations in the long-wavelength limit and chemical short-range order parameter) in the framework of statistical mechanical theory in conjunction with quasi-lattice theory. The Al-Cr phase diagram exhibits the existence of different intermetallic compounds in the solid state, while that of Cr-Ni is a simple eutectic-type phase diagram at high temperatures and includes the low-temperature peritectoid reaction in the range near a CrNi(2) composition. Accordingly, the mixing behaviour in Al-Cr and Cr-Ni alloy melts was studied using the complex formation model in the weak interaction approximation and by postulating Al(8)Cr(5) and CrNi(2) chemical complexes, respectively, as energetically favoured.

Serum and urinary thioredoxin concentrations are associated with severity of children hydronephrosis.

Science.gov (United States)

Xu, Zhe-Ming; Li, Min-Ju; Tao, Chang

2017-03-01

Ureteropelvic junction obstruction (UPJO) is the most common cause of hydronephrosis in children. This study was to assess the relationship between serum thioredoxin (S-Trx) and urinary thioredoxin (U-Trx) concentrations and severity of children hydronephrosis caused by UPJO. This study included 156 hydronephrosis children with unilateral UPJO and 80 healthy children. S-Trx and U-Trx concentrations were measured using enzyme-linked immunosorbent assay. U-Trx/creatinine (cr) ratio was calculated. S-Trx and U-Trx concentrations and U-Trx/cr ratio were significantly higher in hydronephrosis children than in healthy children. They were significantly correlated with split renal function, anterior-posterior diameter and Society for Fetal Urology classification, as well as were independently related to the split renal function 30mm and Society for Fetal Urology grade IV. Under receiver operating characteristic curves, U-Trx/cr ratio showed the higher predictive value compared to S-Trx and U-Trx concentrations. Increased S-Trx and U-Trx concentrations, especially U-Trx/cr ratio, are closely associated with the severity of children hydronephrosis, substantializing Trx as a promising biomarker for the progression of children hydronephrosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Biliary excretion and distribution of 51Cr(III) and 51Cr(VI) in rats

International Nuclear Information System (INIS)

Cikrt, M.; Bencko, V.

1979-01-01

The biliary excretion and distribution of 51 Cr after intravenous administration of 51 Cr(III) ( 51 CrCl 3 ) or 51 Cr(VI) (Na 2 51 CrO 4 .4H 2 O) were studied in rats. The cumulative biliary excretion of 51 Cr 24 hrs after the injection was significantly higher after administration of 51 Cr(VI) than of 51 Cr(III) (3.51+-0.7% and 0.51+-0.05% of administered dose, respectively). This difference was especially due to a higher rate of biliary excretion of 51 Cr in the first hours after 51 Cr(VI) administration. The excretion of 51 Cr via feces was also higher after administration of 51 Cr(VI) (7.35+-0.45%) of administered dose, as against 4.23+-0.23% after 51 Cr(III). On the other hand, no significant difference in urinary excretion of 51 Cr was found. Statistically significant differences were also observed in the distribution of 51 Cr in the organism after administration of both valence states of the metal. (author)

Microstructure and mechanical properties of nanostructure multilayer CrN/Cr coatings on titanium alloy

International Nuclear Information System (INIS)

Wiecinski, Piotr; Smolik, Jerzy; Garbacz, Halina; Kurzydlowski, Krzysztof J.

2011-01-01

Five different nanostructured, multilayer coatings (CrN/Cr)x8 with different thickness ratio of Cr and CrN layers were deposited by PAPVD (Plasma Assisted Physical Vapour Deposition) vacuum arc method on Ti6Al4V titanium alloy. The microstructure, chemical and phase composition of the CrN and Cr sub-layers were characterized by SEM with EDX and Cs-corrected dedicated STEM on cross-sections prepared by focus ion beam. Besides, hardness and Young's modulus of the (Cr/CrN)x8 coatings has been measured. The adhesion has been tested by scratch test method. The obtained (CrN/Cr) multilayer coatings, 5-6 μm in thickness, have homogeneous and nanocrystalline structure, free of pores and cracks. The microstructures of Cr and CrN layers consist of columnar grains below 100 nm in diameter. The hardness and Young's modulus of these coatings depend linearly on thickness ratio of Cr and CrN layers. The decrease of the thickness ratio Cr/CrN 0.81 to 0.15 results in the increase of hardness from 1275 HV to 1710 HV and Young's modulus from 260 GPa to 271 GPa.

Facile and easily popularized synthesis of L-cysteine-functionalized magnetic nanoparticles based on one-step functionalization for highly efficient enrichment of glycopeptides.

Science.gov (United States)

Feng, Xiaoyan; Deng, Chunhui; Gao, Mingxia; Zhang, Xiangmin

2018-01-01

Protein glycosylation is one of the most important post-translational modifications. Also, efficient enrichment and separation of glycopeptides from complex samples are crucial for the thorough analysis of glycosylation. Developing novel hydrophilic materials with facile and easily popularized synthesis is an urgent need in large-scale glycoproteomics research. Herein, for the first time, a one-step functionalization strategy based on metal-organic coordination was proposed and Fe 3 O 4 nanoparticles were directly functionalized with zwitterionic hydrophilic L-cysteine (L-Cys), greatly simplifying the synthetic procedure. The easily synthesized Fe 3 O 4 /L-Cys possessed excellent hydrophilicity and brief composition, contributing to affinity for glycopeptides and reduction in nonspecific interaction. Thus, Fe 3 O 4 /L-Cys nanoparticles showed outstanding sensitivity (25 amol/μL), high selectivity (mixture of bovine serum albumin and horseradish peroxidase tryptic digests at a mass ratio of 100:1), good reusability (five repeated times), and stability (room temperature storage of 1 month). Encouragingly, in the glycosylation analysis of human serum, a total of 376 glycopeptides with 393 N-glycosylation sites corresponding to 118 glycoproteins were identified after enrichment with Fe 3 O 4 /L-Cys, which was superior to ever reported L-Cys modified magnetic materials. Furthermore, applying the one-step functionalization strategy, cysteamine and glutathione respectively direct-functionalized Fe 3 O 4 nanoparticles were successfully synthesized and also achieved efficient glycopeptide enrichment in human serum. The results indicated that we have presented an efficient and easily popularized strategy in glycoproteomics as well as in the synthesis of novel materials. Graphical abstract Fe 3 O 4 /L-Cys nanoparticles based on one-step functionalization for highly efficient enrichment of glycopeptides.

Effect of sildenafil citrate (Viagra®) on trace element concentration in serum and brain of rats.

Science.gov (United States)

Fayed, Abdel-Hasseb A; Gad, Shereen B

2011-12-01

As a vasodilator with good hemodynamic effects, sildenafil has been successfully used in the treatment of patients with pulmonary hypertension and cardiovascular diseases. By selectively inhibiting phosphodiestrase type 5 (PDE-5) and thus effectively reducing the breakdown of c GMP, sildenafil administration can markedly improve the erectile dysfunction. Sildenafil also elevates localized cerebral blood flow in rat brain. The objective of the present study was to investigate the effect of sildenafil on the level of trace elements (Zinc (Zn), copper (Cu), iron (Fe), selenium (Se), cobalt (Co), and chromium (Cr)) in blood and brain of rats. Sixteen male albino rats weighing 180-200 g were divided into two groups (8 rats/group). Sildenafil (Viagra, Pfizer Inc.) was dissolved in saline and administered at a dose of 10mg/kg i.p. (0.5 ml volume) to rats in the treated group every 72 h for 12 injections. Rats in the control group were administered the same volume of saline as in treated group. All rats were sacrificed 24h after the last injection. Blood samples were collected and serum was separated and stored at -20°C. Brains were dissected and stored frozen until analysis. Trace elements concentrations were determined by flame emission atomic absorption spectrophotometer. Results showed that sildenafil injection significantly (P<0.05) increased serum and brain Se and Cu concentrations. Moreover, sildenafil increased the Cr concentration in the brain tissue. It was concluded that sildenafil citrate administration increased serum Se and Cu as well as, increased brain Se, Cu, and Cr concentrations in rats. Copyright © 2011 Elsevier GmbH. All rights reserved.

Cr-Ni ALLOY ELECTRODEPOSITION AND COMPARISON WITH CONVENTIONAL PURE Cr COATING TECHNIQUE

Directory of Open Access Journals (Sweden)

M. Moniruzzaman

2012-12-01

Full Text Available Cr coating is widely used as the outer surface of precision parts due to its attractive appearance and superior corrosion resistance properties. It is obtained by electrodeposition via a conventional bath with hexavalent Cr ions. This manufacturing technique has many drawbacks, such as very low efficiency and high operating temperature and it is hazardous to health. In this work, we studied a Cr-Ni alloy deposition technique and compared the alloy coating properties to those with conventional Cr coating. Sequential two-step alloy electrodeposition was also compared. We took varying concentrations of Cr, Ni and complexing agents for the electrodeposition of Cr-Ni alloy and sequential Cr-Ni alloy coating on mild steel. Operating parameters, i.e. current density and temperature, were varied to examine their effects on the coating properties. The coatings thus obtained were characterized by visual observation, corrosion test, microhardness measurement, morphology and chemical analysis. The Cr-Ni alloy coating was found to be more corrosion resistant in 5% NaCl solution and harder than the pure Cr coating obtained by conventional electrodeposition. Toxic gas was produced in a much lower extent in the alloy coating than the conventional Cr coating technique. Again, the two-step Cr-Ni alloy coating was found better in terms of corrosion resistance as well as hardness compared to the Cr-Ni alloy coating. The process was also found to be much more environmentally friendly.

Electronic structure and magnetic ordering of the semiconducting chromium trihalides CrCl3, CrBr3, and CrI3

KAUST Repository

Wang, Hao

2011-03-01

We present results from an electronic structure investigation of the chromium halides CrCl3, CrBr3, and CrI3, as obtained by the linearized augmented plane wave method of density functional theory. Our interest focuses on the chloride. While all three halides display strong ferromagnetic coupling within the halide-Cr-halide triple layers, our emphasis is on differences in the interlayer magnetic coupling. In agreement with experimental results, our calculations indicate ferromagnetic ordering for CrBr3 as well as CrI3. The antiferromagnetic state of CrCl3 can be reproduced by introducing an on-site electron-electron repulsion. However, we observe that the ground state depends critically on the specific approach used. Our results show that a low temperature structural phase transition from monoclinic to trigonal is energetically favourable for CrCl3. © 2011 IOP Publishing Ltd.

Design of ET(B) receptor agonists: NMR spectroscopic and conformational studies of ET7-21[Leu7, Aib11, Cys(Acm)15].

Science.gov (United States)

Hewage, Chandralal M; Jiang, Lu; Parkinson, John A; Ramage, Robert; Sadler, Ian H

2002-03-01

In a previous report we have shown that the endothelin-B receptor-selective linear endothelin peptide, ET-1[Cys (Acm)1,15, Ala3, Leu7, Aib11], folds into an alpha-helical conformation in a methanol-d3/water co-solvent [Hewage et al. (1998) FEBS Lett., 425, 234-238]. To study the requirements for the structure-activity relationships, truncated analogues of this peptide were subjected to further studies. Here we report the solution conformation of ET7-21[Leu7, Aib11, Cys(Acm)15], in a methanol-d3/water co-solvent at pH 3.6, by NMR spectroscopic and molecular modelling studies. Further truncation of this short peptide results in it displaying poor agonist activity. The modelled structure shows that the peptide folds into an alpha-helical conformation between residues Lys9-His16, whereas the C-terminus prefers no fixed conformation. This truncated linear endothelin analogue is pivotal for designing endothelin-B receptor agonists.

A hot-spot mutation in CDC42 (p.Tyr64Cys) and novel phenotypes in the third patient with Takenouchi-Kosaki syndrome.

Science.gov (United States)

Motokawa, Midori; Watanabe, Satoshi; Nakatomi, Akiko; Kondoh, Tatsuro; Matsumoto, Tadashi; Morifuji, Kanako; Sawada, Hirotake; Nishimura, Toyoki; Nunoi, Hiroyuki; Yoshiura, Koh-Ichiro; Moriuchi, Hiroyuki; Dateki, Sumito

2018-03-01

Takenouchi-Kosaki syndrome (TKS) is a congenital malformation syndrome characterized by severe developmental delay, macrothrombocytopenia, camptodactyly, sensorineural hearing loss, and dysmorphic facial features. Recently, a heterozygous de novo mutation (p.Tyr64Cys) in the CDC42 gene, which encodes a key small GTP-binding protein of the Rho-subfamily, was identified in two unrelated patients with TKS. We herein report a third patient with TKS who had the same heterozygous CDC42 mutation. The phenotype of the patient was very similar to those of the two previously reported patients with TKS; however, she also demonstrated novel clinical manifestations, such as congenital hypothyroidism and immunological disturbance. Thus, despite the heterozygous mutation of CDC42 (p.Tyr64Cys) likely being a hot-spot mutation for TKS, its phenotype may be variable. Further studies and the accumulation of patients with CDC42 mutations are needed to clarify the phenotype in patients with TKS and the pathophysiological roles of the CDC42 mutation.

Albumin Redhill (-1 Arg, 320 Ala → Thr): A glycoprotein variant of human serum albumin whose precursor has an aberrant signal peptidase cleavage site

International Nuclear Information System (INIS)

Brennan, S.O.; Myles, T.; Peach, R.J.; George, P.M.; Donaldson, D.

1990-01-01

Albumin Redhill is an electrophoretically slow genetic variant of human serum albumin that does not bind 63 Ni 2+ and has a molecular mass 2.5 kDa higher than normal albumin. Its inability to bind Ni 2+ was explained by the finding of an additional residue of Arg at position -1. This did not explain the molecular basis of the genetic variation or the increase in apparent molecular mass. Fractionation of tryptic digests on concanavalin A-Sepharose followed by peptide mapping of the bound and unbound fractions and sequence analysis of the glycopeptides identified a mutation of 320 Ala → Thr. This introduces as Asn-Tyr-Thr oligosaccharide attachment sequence centered on Asn-318 and explains the increase in molecular mass. This, however, did not satisfactorily explain the presence of the additional Arg residue at position -1. DNA sequencing of polymerase chain reaction-amplified genomic DNA encoding the prepro sequence of albumin indicated an additional mutation of -2 Arg → Cys. The authors propose that the new Phe-Cys-Arg sequence in the propeptide is an aberrant signal peptidase cleavage site and that the signal peptidase cleaves the propeptide of albumin Redhill in the lumen of the endoplasmic reticulum before it reaches the Golgi vesicles, the site of the diarginyl-specific proalbumin convertase

The association of cysteine with obesity, inflammatory cytokines and insulin resistance in Hispanic children and adolescents.

Directory of Open Access Journals (Sweden)

Amany K Elshorbagy

Full Text Available Plasma total cysteine (tCys independently relates to fat mass in adults. Dietary cyst(eine promotes adiposity and decreases glucose tolerance in some rodent models, but alleviates insulin resistance in others.To investigate whether the association of tCys with body fat extends to children at particular risk of obesity, and whether tCys is associated with insulin resistance and obesity-associated inflammation.We explored the cross-sectional relations of fasting plasma tCys and related metabolites with body composition measured by dual-energy X-ray absorptiometry in 984 Hispanic children and adolescents aged 4-19 years from the Viva La Familia Study. Linear and logistic regression and dose-response curves were used to evaluate relations of tCys with obesity, insulin resistance and inflammatory markers including interleukin-6 (IL-6, tumor necrosis factor-alpha (TNF-α, monocyte chemoattractant protein-1 (MCP-1 and C-reactive protein (CRP.tCys, methionine and total homocysteine (tHcy increased with age. Upper tCys quartile was independently associated with a 5-fold increased risk of obesity (95% CI 3.5-8.0, P<0.001, and 2-fold risk of insulin resistance (95% CI: 1.6-5.0, P<0.001; adjusted for body fat%. Within the overweight/obese subgroup, but not in normal-weight children, tCys accounted for 9% of the variability in body fat% (partial r = 0.30, P<0.001; adjusted for age and gender. tCys correlated positively with serum non-esterified fatty acids and leptin, partly independent of body fat, but was not associated with serum IL-6, TNF-α or MCP-1. A positive correlation with CRP disappeared after adjustment for BMI.tCys is independently associated with obesity and insulin resistance in Hispanic children and adolescents, highlighting a previously underappreciated link between the sulfur amino acid metabolic pathway and obesity and cardiometabolic risk.

Níveis séricos de vitamina D e periodontite crônica em pacientes com doença renal crônica Serum levels of vitamin D and chronic periodontitis in patients with chronic kidney disease

Directory of Open Access Journals (Sweden)

Jessica do Amaral Bastos

2013-03-01

Full Text Available INTRODUÇÃO A concomitância de periodontite crônica (PC em pacientes com doença renal crônica (DRC tem sido associada a desfechos adversos. A deficiência de vitamina D (25(OHD parece desempenhar papel importante na PC e níveis inadequados de vitamina D têm sido descritos em pacientes com DRC. OBJETIVO: Examinar a relação entre níveis séricos de vitamina D e PC em pacientes com DRC pré-dialítica. MÉTODO: Estudo de caso-controle, definidos, respectivamente, como pacientes com DRC e PC e DRC sem PC. Os dados demográficos, de exame físico e laboratoriais foram obtidos no dia da consulta. A DRC foi definida e estagiada segundo a NKF QDOKI TM. Os níveis séricos de 25(OH D foram dosados por quimioluminescência quando da avaliação da PC, a qual foi caracterizada segundo os critérios de Academia Americana de Periodontologia (1999. Os resultados de 25(OHD foram estratificados em deficiência ( 30 ηg/mL. RESULTADOS: Um total de 29 pacientes foram estudados, 15 no grupo caso e 14 no grupo controle. Os pacientes casos apresentaram mediana de 25(OH D inferior a dos pacientes controles (22,6 vs. 28,6 ηg/mL; p INTRODUCTION: Concomitance of chronic periodontitis (CP in patients with chronic kidney disease (CKD have been associated with adverse outcomes. Vitamin D (25(OHD deficiency my play a role in CP and inadequate vitamin D status is common among patients with CKD. OBJECTIVE: To examine the relationship between vitamin 25(OHD and CP in patients with CKD not yet on dialysis. METHOD: A case-control study was conducted. Cases and controls were defined as patients with CKD with and without CP, respectively. The demographic, clinical and laboratory data were obtained when the patient was attended in the outpatient clinic. CKD was defined and staged according to the NKF QDOKI TM. Serum 25(OH D levels were measured by chemiluminescence when assessing the CP, which was definined according to the American Academy of Periodontoly (1999. Serum

Structure and magnetic properties of Cr nanoparticles and Cr2O3 nanoparticles

International Nuclear Information System (INIS)

Zhang, W.S.; Brueck, E.; Zhang, Z.D.; Tegus, O.; Li, W.F.; Si, P.Z.; Geng, D.Y.; Buschow, K.H.J.

2005-01-01

We have synthesized Cr nanoparticles by arc-discharge and Cr 2 O 3 nanoparticles by subsequent annealing the as-prepared Cr nanoparticles. The structure of these nanoparticles is studied by means of X-ray diffraction, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscope. Most of the particles show a good crystal habit of well-defined cubic or orthorhombic shape, while some small particles show spherical shape. The as-prepared Cr nanoparticles have a BCC Cr core coated with a thin Cr 2 O 3 layer. Cr in the core of the particles heated at 873 K for 4 h is changed to Cr 2 O 3 . The results of magnetic measurements show that the Cr nanoparticles exhibit mainly antiferromagnetic properties, in addition to a weak-ferromagnetic component at lower fields. The weak-ferromagnetic component may be ascribed to uncompensated surface spins. For the field-cooled Cr 2 O 3 nanoparticles, an exchange bias is observed in the hysteresis loops, which can be interpreted as the exchange coupling between the uncompensated spins at the surface and the spins in the core of the Cr 2 O 3 nanoparticles

The Effect of Lean-Seafood and Non-Seafood Diets on Fasting and Postprandial Serum Metabolites and Lipid Species

DEFF Research Database (Denmark)

Schmedes, Mette; Balderas, Claudia; Aadland, Eli Kristin

2018-01-01

The metabolic effects associated with intake of different dietary protein sources are not well characterized. We aimed to elucidate how two diets that varied in main protein sources affected the fasting and postprandial serum metabolites and lipid species. In a randomized controlled trial with cr...

Mechanistic studies on β-ketoacyl thiolase from Zoogloea ramigera: Identification of the active-site nucleophile as Cys89, its mutation to Ser89, and kinetic and thermodynamic characterization of wild-type and mutant enzymes

International Nuclear Information System (INIS)

Thompson, S.; Mayerl, F.; Walsh, C.T.; Peoples, O.P.; Masamune, S.; Sinskey, A.J.

1989-01-01

Thiolase proceeds via covalent catalysis involving an acetyl-S-enzyme. The active-site thiol nucleophile is identified as Cys 89 by acetylation with [ 14 C]acetyl-CoA, rapid denaturation, tryptic digestion, and sequencing of the labeled peptide. The native acetyl enzyme is labile to hydrolytic decomposition with t 1/2 of 2 min at pH 7, 25 degree C. Cys 89 has been converted to the alternate nucleophile Ser 89 by mutagenesis and the C89S enzyme overproduced, purified, and assessed for activity. The Ser 89 enzyme retains 1% of the V max of the Cys 89 enzyme in the direction of acetoacetyl-CoA thiolytic cleavage and 0.05% of the V max in the condensation of two acetyl-CoA molecules. A covalent acetyl-O-enzyme intermediate is detected on incubation with [ 14 C]acetyl-CoA and isolation of the labeled Ser 89 -containing tryptic peptide. Comparisons of the Cys 89 and Ser 89 enzymes have been made for kinetic and thermodynamic stability of the acetyl enzyme intermediates both by isolation and by analysis of [ 32 P]CoASH/acetyl-CoA partial reactions and for rate-limiting steps in catalysis with trideuterioacetyl-CoA

Population pharmacokinetics of teicoplanin in hospitalized elderly patients using cystatin C as an indicator of renal function.

Science.gov (United States)

Kasai, Hidefumi; Tsuji, Yasuhiro; Hiraki, Yoichi; Tsuruyama, Moeko; To, Hideto; Yamamoto, Yoshihiro

2018-04-01

Serum cystatin C (CysC) has recently been proposed as an alternative marker to serum creatinine (SCR) for estimating renal clearance. In the present study, we performed a population pharmacokinetic analysis of teicoplanin (TEIC), which is mainly eliminated through the kidneys, using CysC as a predictor for renal clearance. Thirty-six patients with MRSA infections who were administrated to the National Hospital Organization Beppu Medical Center between January 2012 and December 2013 were enrolled and gave 123 sets of blood TEIC concentration data. Renal clearance was estimated by the Hoek equation using CysC, by creatinine clearance predicted by the Cockcroft-Gault equation using SCR, or directly by CysC. One compartment open model with inter-individual variabilities for renal clearance and the volume of distribution as well as an additional residual error model was used to estimate population pharmacokinetic parameters for TEIC. The model with the best predictability was that with CysC as a predictor for renal clearance; it showed better significance than the models using estimated the glomerular filtration rate by the Hoek equation or CLcr. The final model was as follows: CL (L/hr) = 0.510 × (CysC/1.4) -0.68  × Total body weight/60 0.81 , omega (CL) = 19.8% CV, VC (L) = 78.1, omega (V) = 42.7% CV. The present results show the usefulness of CysC to more accurately predict the pharmacokinetics of drugs mainly eliminated through the kidneys, such as TEIC. However, since the sample size in this study was relatively small, further investigations on renal clearance predictability using CysC are needed. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Homogeneous and Heterogeneous (Fex, Cr1-x)(OH)3 Precipitation: Implications for Cr Sequestration.

Science.gov (United States)

Dai, Chong; Zuo, Xiaobing; Cao, Bo; Hu, Yandi

2016-02-16

The formation of (Fe, Cr)(OH)3 nanoparticles determines the fate of aqueous Cr in many aquatic environments. Using small-angle X-ray scattering, precipitation rates of (Fe, Cr)(OH)3 nanoparticles in solution and on quartz were quantified from 0.1 mM Fe(III) solutions containing 0-0.25 mM Cr(III) at pH = 3.7 ± 0.2. Concentration ratio of aqueous Cr(III)/Fe(III) controlled the chemical composition (x) of (Fex, Cr1-x)(OH)3 precipitates, solutions' supersaturation with respect to precipitates, and the surface charge of quartz. Therefore, the aqueous Cr(III)/Fe(III) ratio affected homogeneous (in solution) and heterogeneous (on quartz) precipitation rates of (Fex, Cr1-x)(OH)3 through different mechanisms. The sequestration mechanisms of Cr(III) in precipitates were also investigated. In solutions with high aqueous Cr(III)/Fe(III) ratios, surface enrichment of Cr(III) on the precipitates occurred, resulting in slower particle growth in solutions. From solutions with 0-0.1 mM Cr(III), the particles on quartz grew from 2 to 4 nm within 1 h. Interestingly, from solution with 0.25 mM Cr(III), particles of two distinct sizes (2 and 6 nm) formed on quartz, and their sizes remained unchanged throughout the reaction. Our study provided new insights on homogeneous and heterogeneous precipitation of (Fex, Cr1-x)(OH)3 nanoparticles, which can help determine the fate of Cr in aquatic environments.

Hot corrosion of Co-Cr, Co-Cr-Al, and Ni-Cr alloys in the temperature range of 700-750 deg C

Science.gov (United States)

Chiang, K. T.; Meier, G. H.

1980-01-01

The effect of SO3 pressure in the gas phase on the Na2SO4 induced hot corrosion of Co-Cr, Ni-Cr, and Co-Cr-Al alloys was studied in the temperature range 700 to 750 C. The degradation of the Co-Cr and Ni-Cr alloys was found to be associated with the formation of liquid mixed sulfates (CoSO4-Na2SO4 or NiSO4-Na2SO4) which provided a selective dissolution of the Co or Ni and a subsequent sulfidation oxidation mode of attack which prevented the maintenance of a protective Cr2O3 film. A clear mechanism was not developed for the degradation of Co-Cr-Al alloys. A pitting corrosion morphology was induced by a number of different mechanisms.

Lipoxin A4 stable analogs reduce allergic airway responses via mechanisms distinct from CysLT1 receptor antagonism.

Science.gov (United States)

Levy, Bruce D; Lukacs, Nicholas W; Berlin, Aaron A; Schmidt, Birgitta; Guilford, William J; Serhan, Charles N; Parkinson, John F

2007-12-01

Cellular recruitment during inflammatory/immune responses is tightly regulated. The ability to dampen inflammation is imperative for prevention of chronic immune responses, as in asthma. Here we investigated the ability of lipoxin A4 (LXA4) stable analogs to regulate airway responses in two allergen-driven models of inflammation. A 15-epi-LXA4 analog (ATLa) and a 3-oxa-15-epi-LXA4 analog (ZK-994) prevented excessive eosinophil and T lymphocyte accumulation and activation after mice were sensitized and aerosol-challenged with ovalbumin. At 50% and to a greater extent than equivalent doses of the CysLT1 receptor antagonist montelukast. Distinct from montelukast, ATLa treatment led to marked reductions in cysteinyl leukotrienes, interleukin-4 (IL-4), and IL-10, and both ATLa and ZK-994 inhibited levels of IL-13. In cockroach allergen-induced airway responses, both intraperitoneal and oral administration of ZK-994 significantly reduced parameters of airway inflammation and hyper-responsiveness in a dose-dependent manner. ZK-994 also significantly changed the balance of Th1/Th2-specific cytokine levels. Thus, the ATLa/LXA4 analog actions are distinct from CysLT1 antagonism and potently block both allergic airway inflammation and hyper-reactivity. Moreover, these results demonstrate these analogs' therapeutic potential as new agonists for the resolution of inflammation.

Biomarkers of acute kidney injury in neonatal encephalopathy.

LENUS (Irish Health Repository)

Sweetman, D U

2013-03-01

Acute kidney injury (AKI) is a common complication of neonatal encephalopathy (NE). The accurate diagnosis of neonatal AKI, irrespective of the cause, relies on suboptimal methods such as identification of rising serum creatinine, decreased urinary output and glomerular filtration rate. Studies of AKI biomarkers in adults and children have shown that biomarkers can improve the early diagnosis of AKI. Hypoxia-ischaemia is the proposed aetiological basis of AKI in both NE and cardiopulmonary bypass (CPB). However, there is a paucity of studies examining the role of AKI biomarkers specifically in NE. Urinary cystatin C (CysC), neutrophil gelatinase-associated lipocalin (NGAL), interleukin-18, kidney injury molecule-1, liver-type fatty acid-binding protein, serum CysC and serum NGAL all show good ability to predict early AKI in a heterogeneous critically ill neonatal population including infants post-CPB. Moreover, serum and urinary NGAL and urinary CysC are early predictors of AKI secondary to NE. These findings are promising and open up the possibility of biomarkers playing a significant role in the early diagnosis and treatment of NE-related AKI. There is an urgent need to explore the role of AKI biomarkers in infants with NE as establishing the diagnosis of AKI earlier may allow more timely intervention with potential for improving long-term outcome.

[Haplotype Analysis of Coagulation Factor VII Gene in a Patient with Congenital Coagulation Factor VII Deficiency with Heterozygous p.Arg337Cys Mutation and o.Aro413Gin Polymorphism..

Science.gov (United States)

Suzuki, Keijiro; Yoshioka, Tomoko; Obara, Takehiro; Suwabe, Akira

2016-05-01

Congenital coagulation factor VII (FVII) deficiency is a rare hemorrhagic disease with an autosomal reces- sive inheritance pattern. We analyzed coagulation factor VII gene (F7) of a patient with FVII deficiency and used expression studies to investigate the effect of a missense mutation on FVII secretion. The proband, a 69-year-old Japanese woman, had a history of postpartum bleeding and excessive bleeding after dental extrac- tion. She was found to have mildly increased PT-INR (1.17) before an ophthalmic operation. FVII activity and antigen were reduced (29.0% and 32.8%). Suspecting that the proband was FVII deficient, we analyzed F7 of the patient. Sequence analysis revealed that the patient was heterozygous for a point mutation (p.Arg337Cys) in the catalytic domain and polymorphisms: the decanucleotide insertion at the promoter re- gion, dimorphism (c.525C >T) in exon 5, and p.Arg413Gln in exon 8. Haplotype analysis clarified that p.Arg337Cys was located on the p.Arg413 allele (Ml allele). The other allele had the p.Arg413Gln polymor- phism(M2 allele) which is known to produce less FVII. Expression studies revealed that p.Arg337Cys causes impairment of FVII secretion. Insufficient secretion of FVII arising from both the p.Arg337Cys/M1 allele and the p.Arg337/M2 allele might lower the FVII level of this patient(<50%). The FVII level in a heterozygous FVII deficient patient might be influenced by F7 polymorphisms on the normal allele. There- fore, genetic analyses are important for the diagnosis of heterozygous FVII deficiency.

Effects of different levels of coconut fiber on blood glucose, serum insulin and minerals in rats.

Science.gov (United States)

Sindurani, J A; Rajamohan, T

2000-01-01

The effect of neutral detergent fiber (NDF) from coconut kernel (Cocos nucifera L) in rats fed 5%, 15% and 30% level on the concentration of blood glucose, serum insulin and excretion of minerals was studied. Increase in the intake of fiber resulted in significant decrease in the level of blood glucose and serum insulin. Faecal excretion of Cu, Cr, Mn, Mg, Zn and Ca was found to increase in rats fed different levels of coconut fiber when compared to fiber free group. The result of the present investigation suggest that inclusion of coconut fiber in the diet results in significant hypoglycemic action.

Determination of trace elements in human blood serum and in the standard reference material ''Bovine Liver'' by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Behne, D.; Juergensen, H.

1978-01-01

Ag, Br, Co, Cr, Cs, Fe, Na, Rb, Sb, Se and Zn were determined in biological materials by gamma-spectrometry of long-lived radionuclides after long-time irradiation with thermal neutrons. Blood was taken from a vein in the arm of the test person via an indwelling plastic cannula. The serum was separated from other blood components by centrifugation and stored at a temperature of -20 deg C. Ampoules of high purity silica quartz were chosen as irradiation containers. The vials were cleaned by etching with 40% hydrofluoric acid. For the analysis 300 μl of serum were taken. The ampoules were irradiated for 10 days at a thermal neutron flux density of 5.10 13 n.cm -2 .sec -1 . They were then cleaned by etching for 5 min with hydrofluoric acid. The gamma-ray spectra of the irradiated samples were measured twice. From the first spectra, which were obtained 10 days after irradiation, the concentrations of Br and Na were calculated. From the gamma-peaks after a decay time of 3 months Ag, Co, Cr, Cs, Fe, Rb, Sc, Se and Zn were determined. The accuracy and precision of the procedure were tested, using the standard reference material ''Bovine Liver'' and identical serum samples. In the case of blood serum the method proved to be suitable for the determination of Br, Cs, Fe, Na, Rb, Se and Zn. By analysing samples from several subjects information about element levels in human serum was obtained. (T.G.)

Vitamin D supplementation during short-term caloric restriction in healthy overweight/obese older women: Effect on glycemic indices and serum osteocalcin levels.

Science.gov (United States)

Sukumar, D; Shapses, S A; Schneider, S H

2015-07-15

The effect of vitamin D supplementation and caloric restriction (CR) on glycemic indices and osteocalcin (OC) is not clear. In this randomized controlled double blind trial, we examined whether vitamin D3 supplementation at 2500 IU/d (D) or placebo has differential effects on markers of insulin sensitivity and bone turnover in overweight/obese postmenopausal women during 6 weeks of caloric restriction (weight loss; WL, n = 39) compared to weight maintenance (WM, n = 37). Seventy-six women (57 ± 6 years) completed this study and the WL groups lost 4 ± 1% of body weight. Baseline serum 25-hydroxyvitamin D (25OHD) was 24.8 ± 5.6 ng/mL at baseline; the rise was greatest in WL-D group (p < 0.05). There was an interaction between vitamin D intake and weight on serum OC, insulin, glucose and markers of insulin sensitivity (p < 0.05). The change in OC was explained by changes in serum 25OHD and insulin (model R(2) = 25.6%). Overall, vitamin D supplementation and CR influence serum osteocalcin levels and modestly favor improvements in insulin sensitivity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The role of the Cys23Ser (rs6318) polymorphism of the HTR2C gene in suicidal behavior: systematic review and meta-analysis.

Science.gov (United States)

González-Castro, Thelma B; Hernandez-Diaz, Yazmín; Juárez-Rojop, Isela E; López-Narváez, Lilia; Tovilla-Zárate, Carlos A; Rodriguez-Perez, José M; Sánchez-de la Cruz, Juan P

2017-12-01

The polymorphisms of the serotonin receptor 2C (HTR2C) gene have been proposed to influence suicidal behavior. The aim of our study was to explore the role of the HTR2C gene variant Cys23Ser (rs6318) in the pathogenesis of suicidal behavior through a systematic review and meta-analysis. The search was performed using EBSCO and PubMed databases. To be included in the analysis, the studies had to evaluate suicidal behavior (attempted, ideation, or completed suicide). The results of the meta-analysis were expressed as odds ratios (ORs). Because HTR2C lies on chromosome X, pooled ORs were calculated, respectively, for each of the models used, namely: allelic, homozygous, dominant, and recessive for the female group and allelic for the male group. The meta-analysis comprised 3867 individuals, including 1668 cases and 2199 controls. The HTR2C Cys23Ser (rs6318) polymorphism did not show a significant association with suicidal behavior either in women (OR: 0.75; 95% confidence interval: 0.55-1.00) or in men (OR: 0.89; 95% confidence interval: 0.64-1.23). Similarly, nonsignificant associations were observed for all of the genetic models used in any of the populations/subgroups studied. Our findings suggest that the rs6318 (Cys23Ser) polymorphism is not associated with suicidal behavior. However, because of the study limitations, we suggest more researches should be performed, increasing the sample sizes and statistical power, to determine the association between the rs6318 variant and suicidal behavior.

Chromium sorption and Cr(VI) reduction to Cr(III) by grape stalks and yohimbe bark.

Science.gov (United States)

Fiol, Núria; Escudero, Carlos; Villaescusa, Isabel

2008-07-01

In this work, two low cost sorbents, grape stalks and yohimbe bark wastes were used to remove Cr(VI) and Cr(III) from aqueous solutions. Batch experiments were designed to obtain Cr(VI) and Cr(III) sorption data. The mechanism of Cr(III) and Cr(VI) removal and Cr(VI) reduction to Cr(III) by the two vegetable wastes, has been investigated. Fourier transform infrared rays (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis on solid phase were performed to determine the main functional groups that might be involved in metal uptake and to confirm the presence of Cr(III) on the sorbent, respectively. Results put into evidence that both sorbents are able to reduce Cr(VI) to its trivalent form.

First-Principles Calculations for Chemical Reaction between Sodium Diethyldithiocarbamate and Transition-Metal (Cr) atom to Produce Cr(DDC)3 and Cr(DDC)2ODDC

Science.gov (United States)

Setiyanto, Henry; Muhida, Rifki; Kishi, Tomoya; Rempillo, Ofelia; Rahman, Mahmudur; Dipojono, Hermawan Kresno; Di\\ {n}o, Wilson Agerico; Matsumoto, Shigeno; Kasai, Hideaki

2006-10-01

We investigate the chemical reaction between a Cr transition-metal atom and sodium diethyldithiocarbamate (NaDDC), a complexing agent used to detect and extract Cr in human blood samples. Using density-functional-theory-based calculations, we determine their stable structures of Cr(DDC)2ODDC and Cr(DDC)3 complexes and obtain their dissociation energies. We found dissociation energies of -10.66 and -3.24 eV for Cr(DDC)2ODDC and Cr(DDC)3 complexes, respectively. Hence, on the basis of dissociation energies, we have verified that the reaction of NaDDC with Cr produces Cr(DDC)2ODDC as a major product.

In silico CrNF, a half-metallic ferromagnetic nitride–fluoride mimicking CrO2

International Nuclear Information System (INIS)

Matar, Samir F.

2014-01-01

Isoelectronic with CrO 2 , CrNF is proposed in silico based on rutile derived structures with DFT computations. The ground state structure defined from cohesive energies is of MgUO 4 -type, characterized by short covalent Cr–N and long ionic Cr–F distances. Like CrO 2 it is a half-metallic ferromagnet with M=2 μ B /FU integer magnetization with reduced band gap at minority spins. Major difference of magnetic response to pressure characterizes CrNF as a soft ferromagnet versus hard magnetic CrO 2 . The chemical bonding properties point to prevailing covalent Cr–N versus ionic Cr–F bonding. Different synthesis routes are examined. - Highlights: • DFT identification of CrNF is based on isoelectronicity and rutile derivatives. • Similarly to CrO 2 , CrNF is a half-metallic ferromagnet with reduced band gap. • Strong pressure dependence of magnetization of CrNF oppositely to CrO 2 . • Covalent Cr–N bonding prevails in spite of the presence of ionic Cr–F. • Cohesive energies favor the synthesis for which protocols are proposed

Correlation of microstructure and fracture toughness of advanced 9Cr/CrMoV dissimilarly welded joint

Energy Technology Data Exchange (ETDEWEB)

Guo, Qian [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Lu, Fenggui, E-mail: Lfg119@sjtu.edu.cn [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Liu, Xia [Shanghai Turbine Plant of Shanghai Electric Power Generation Equipment Co. Ltd., Shanghai 200240 (China); Yang, Renjie [Shanghai Turbine Works Company, Shanghai 200240 (China); Cui, Haichao [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Gao, Yulai, E-mail: ylgao@shu.edu.cn [State Key Laboratory of Advanced Special Steels, Shanghai University, Shanghai 200072 (China)

2015-06-25

In this paper, the fracture toughness and the related microstructure characteristics of dissimilarly welded joint manufactured by advanced 9Cr and CrMoV steels were systematically investigated. The dissimilarly welded joint was fabricated by narrow gap submerged arc welding (NG-SAW) applying multi-layer and multi-pass technique. Fracture toughness, as one of the most important property to assess the reliability of welded joint, was studied for different regions including CrMoV base metal (CrMoV-BM), heat affected zone (HAZ) of CrMoV side (CrMoV-HAZ), weld metal (WM), heat affected zone of 9Cr side (9Cr-HAZ) and 9Cr base metal (9Cr-BM). It was found that the fracture toughness of CrMoV-BM, CrMoV-HAZ and WM was better than that of 9Cr-HAZ and 9Cr-BM. In order to illustrate these results, the microstructure of the whole welded joint was observed by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM) detailedly. It was found that the fine high-temperature tempered martensite and bainite in WM, CrMoV-BM and CrMoV-HAZ contribute to the higher fracture toughness, while lower fracture toughness for 9Cr-BM and HAZ was caused by coarse tempered lath-martensite. Furthermore, the fracture morphology showed that ductile fracture occurred in WM and CrMoV side, while brittle fracture appeared in BM and HAZ of 9Cr side.

Low-field spin dynamics of Cr7Ni and Cr7Ni-Cu -Cr 7Ni molecular rings as detected by μ SR

Science.gov (United States)

Sanna, S.; Arosio, P.; Bordonali, L.; Adelnia, F.; Mariani, M.; Garlatti, E.; Baines, C.; Amato, A.; Sabareesh, K. P. V.; Timco, G.; Winpenny, R. E. P.; Blundell, S. J.; Lascialfari, A.

2017-11-01

Muon spin rotation measurements were used to investigate the spin dynamics of heterometallic Cr7Ni and Cr7Ni -Cu-Cr7Ni molecular clusters. In Cr7Ni the magnetic ions are arranged in a quasiplanar ring and interact via an antiferromagnetic exchange coupling constant J , while Cr7Ni -Cu-Cr7Ni is composed of two Cr7Ni linked by a bridging moiety containing one Cu ion, that induces an inter-ring ferromagnetic interaction J'≪J . The longitudinal muon relaxation rate λ collected at low magnetic fields μ0H BPP)-like heuristic fitting model that takes into account of a distribution of electronic spin characteristic times for T >5 K, while the shoulder presented by Cr7Ni can be reproduced by a BPP function that incorporates a single electronic characteristic time theoretically predicted to dominate for T <5 K. The flattening of λ (T ) in Cr7Ni -Cu-Cr7Ni occurring at very low temperature can be tentatively attributed to field-dependent quantum effects and/or to an inelastic term in the spectral density of the electronic spin fluctuations.

Cr(III) and Cr(VI) in leather and elicitation of eczema

DEFF Research Database (Denmark)

Hansen, Malene Barré; Menne, Torkil; Johansen, Jeanne Duus

2006-01-01

The aim of the present study was to investigate the relation between the content of Cr(VI) and soluble Cr(III) in leather and the ability of the leather to elicit eczema in chromium allergic patients. An array of chromium-tanned leather samples was analysed for the content of total Cr(VI) and sol...

Colorimetric detection of Cr (VI) based on the leaching of gold nanoparticles using a paper-based sensor.

Science.gov (United States)

Guo, Jian-Feng; Huo, Dan-Qun; Yang, Mei; Hou, Chang-Jun; Li, Jun-Jie; Fa, Huan-Bao; Luo, Hui-Bo; Yang, Ping

2016-12-01

Herein, we have developed a simple, sensitive and paper-based colorimetric sensor for the selective detection of Chromium (Ⅵ) ions (Cr (VI)). Silanization-titanium dioxide modified filter paper (STCP) was used to trap bovine serum albumin capped gold nanoparticles (BSA-Au NPs), leading to the fabrication of BSA-Au NPs decorated membrane (BSA-Au NPs/STCP). The BSA-Au NPs/STCP operated on the principle that BSA-Au NPs anchored on the STCP were gradually etched by Cr (VI) as the leaching process of gold in the presence of hydrobromic acid (HBr) and hence induced a visible color change. Under optimum conditions, the paper-based colorimetric sensor showed clear color change after reaction with Cr (VI) as well as with favorable selectivity to a variety of possible interfering counterparts. The amount-dependent colorimetric response was linearly correlated with the Cr (VI) concentrations ranging from 0.5µM to 50.0µM with a detection limit down to 280nM. Moreover, the developed cost-effective colorimetric sensor has been successfully applied to real environmental samples which demonstrated the potential for field applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Electronic structure and magnetic ordering of the semiconducting chromium trihalides CrCl3, CrBr3, and CrI3

KAUST Repository

Wang, Hao; Eyert, Volker; Schwingenschlö gl, Udo

2011-01-01

for CrBr3 as well as CrI3. The antiferromagnetic state of CrCl3 can be reproduced by introducing an on-site electron-electron repulsion. However, we observe that the ground state depends critically on the specific approach used. Our results show that a

Mathematical models applied to the Cr(III) and Cr(VI) breakthrough curves.

Science.gov (United States)

Ramirez C, Margarita; Pereira da Silva, Mônica; Ferreira L, Selma G; Vasco E, Oscar

2007-07-19

Trivalent and hexavalent chromium continuous biosorption was studied using residual brewer Saccharomyces cerevisiae immobilized in volcanic rock. The columns used in the process had a diameter of 4.5 cm and a length of 140 cm, working at an inlet flow rate of 15 mL/min. Breakthrough curves were used to study the yeast biosorption behavior in the process. The saturation time (ts) was 21 and 45 h for Cr(III) and Cr(VI), respectively, and a breakthrough time (tb) of 4 h for Cr(III) and 5 h for Cr(VI). The uptake capacity of the biosorbent for Cr(III) and Cr(VI) were 48 and 60 mg/g, respectively. Two non-diffusional mathematical models with parameters t0 and sigma were used to adjust the experimental data obtained. Microsoft Excel tools were used for the mathematical solution of the two parameters used.

The lattice distortion effect for zinc-blende CrAs and CrSb

International Nuclear Information System (INIS)

Yamana, Keita; Geshi, Masaaki; Tsukamoto, Hidekazu; Uchida, Ichiro; Shirai, Masafumi; Kusakabe, Koichi; Suzuki, Naoshi

2004-01-01

We investigated the stability of the ferromagnetism of CrAs and CrSb in the zinc-blende structure against the lattice distortion, systematically. A calculation within the generalized gradient approximation using a full potential linearized augmented plane wave method was performed. We compared the ferromagnetic state and the antiferromagnetic state assuming tetragonal distortion with the lattice constants a and c changing independently and determined the spin polarization ratio in the ferromagnetic phase. The result shows that complete spin polarization (half-metallic ferromagnetism) remains stable even in the presence of large tetragonal distortion. On the other hand, our calculation shows that two monolayers of CrAs is enough to produce a half-metallic state in the CrAs/GaAs multilayer. Thus, the present result suggests that the half-metallic nature persists in various atomic-scale superlattices made of distorted CrAs or CrSb

Cystatin C, CRP, log TG/HDLc and metabolic syndrome are associated with microalbuminuria in hypertension

Energy Technology Data Exchange (ETDEWEB)

Moura, Rafaela do Socorro Souza e Silva [Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília, Brasília, DF (Brazil); Vasconcelos, Daniel França [Área de Cardiologia, Faculdade de Medicina, Universidade de Brasília, Brasília, DF (Brazil); Freitas, Eduardo [Departamento de Estatística, Universidade de Brasília, Brasília, DF (Brazil); Moura, Flavio José Dutra de; Rosa, Tânia Torres; Veiga, Joel Paulo Russomano, E-mail: joelprv@unb.br [Área de Clínica Médica, Nefrologia, Faculdade de Medicina, Universidade de Brasília, Brasília, DF (Brazil)

2014-01-15

In patients with systemic hypertension, microalbuminuria is a marker of endothelial damage and is associated with an increased risk for cardiovascular disease. To determine the factors that may lead to the occurrence of microalbuminuria in hypertensive patients with serum creatinine lower than 1.5 mg/dL. This cross-sectional study included 133 Brazilians with essential hypertension followed up at a hypertension outpatient clinic. Those with serum creatinine higher than 1.5 mg/dL, as well as those with diabetes mellitus, were excluded. Systolic and diastolic blood pressures were measured, and body mass index (BMI) and GFR estimated by using the CKD-EPI formula were calculated. The serum levels of the following were assessed: CysC, creatinine, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, C-reactive protein (CRP) and fasting glucose. Microalbuminuria was determined in 24-hour urine. Hypertensive patients were classified according to the presence of one or more criteria for metabolic syndrome. In a multiple regression analysis, the serum levels of CysC and CRP, the atherogenic index log TG/HDLc and the presence of three or more criteria for metabolic syndrome were positively correlated with microalbuminuria (r{sup 2}: 0.277, p < 0.05). CysC, CRP, log TG/HDLc, and the presence of three or more criteria for metabolic syndrome, regardless of serum creatinine, were associated with microalbuminuria, an early marker of kidney damage and cardiovascular risk in patients with essential hypertension.

Cystatin C, CRP, log TG/HDLc and metabolic syndrome are associated with microalbuminuria in hypertension

International Nuclear Information System (INIS)

Moura, Rafaela do Socorro Souza e Silva; Vasconcelos, Daniel França; Freitas, Eduardo; Moura, Flavio José Dutra de; Rosa, Tânia Torres; Veiga, Joel Paulo Russomano

2014-01-01

In patients with systemic hypertension, microalbuminuria is a marker of endothelial damage and is associated with an increased risk for cardiovascular disease. To determine the factors that may lead to the occurrence of microalbuminuria in hypertensive patients with serum creatinine lower than 1.5 mg/dL. This cross-sectional study included 133 Brazilians with essential hypertension followed up at a hypertension outpatient clinic. Those with serum creatinine higher than 1.5 mg/dL, as well as those with diabetes mellitus, were excluded. Systolic and diastolic blood pressures were measured, and body mass index (BMI) and GFR estimated by using the CKD-EPI formula were calculated. The serum levels of the following were assessed: CysC, creatinine, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, C-reactive protein (CRP) and fasting glucose. Microalbuminuria was determined in 24-hour urine. Hypertensive patients were classified according to the presence of one or more criteria for metabolic syndrome. In a multiple regression analysis, the serum levels of CysC and CRP, the atherogenic index log TG/HDLc and the presence of three or more criteria for metabolic syndrome were positively correlated with microalbuminuria (r 2 : 0.277, p < 0.05). CysC, CRP, log TG/HDLc, and the presence of three or more criteria for metabolic syndrome, regardless of serum creatinine, were associated with microalbuminuria, an early marker of kidney damage and cardiovascular risk in patients with essential hypertension

Bioaccumulation and subcellular partitioning of Cr(III) and Cr(VI) in the freshwater green alga Chlamydomonas reinhardtii

Energy Technology Data Exchange (ETDEWEB)

Aharchaou, Imad [Laboratoire Interdisciplinaire des Environnements Continentaux, UMR 7360, Université de Lorraine and CNRS, 8 rue du Général Delestraint, 57070 Metz (France); Rosabal, Maikel; Liu, Fengjie [Institut National de la Recherche Scientifique, Centre Eau Terre Environnement (INRS-ETE), 490 rue de la Couronne, Québec (Québec) G1K 9A9 (Canada); Battaglia, Eric; Vignati, Davide A.L. [Laboratoire Interdisciplinaire des Environnements Continentaux, UMR 7360, Université de Lorraine and CNRS, 8 rue du Général Delestraint, 57070 Metz (France); Fortin, Claude, E-mail: claude.fortin@ete.inrs.ca [Institut National de la Recherche Scientifique, Centre Eau Terre Environnement (INRS-ETE), 490 rue de la Couronne, Québec (Québec) G1K 9A9 (Canada)

2017-01-15

Highlights: • C. reinhardtii accumulated similar levels of Cr(III) and Cr(VI). • The subcellular partitioning of Cr(III) and Cr(VI) was similar. • Cr(III) and Cr(VI) associated mainly with organelles and heat-stable proteins. • Metallomic analysis showed two main Cr-binding biomolecules after 72 h of exposure. - Abstract: Chromium occurs in aquatic environments under two main redox forms, namely Cr(III) and Cr(VI), with different geochemical and biochemical properties. Cr(VI) readily crosses biological membranes of living organisms and once inside the cells it undergoes a rapid reduction to Cr(III). The route of entry for the latter form is, however, poorly known. Using the radioactive tracer {sup 51}Cr we compared the accumulation (absorption and adsorption) of the two Cr forms by the green unicellular alga Chlamydomonas reinhardii after 1 h and 72 h of exposure to 100 nM of either Cr(III) or Cr(VI) at pH 7. Both Cr forms had similar accumulation, with a major part in the extracellular (adsorbed) fraction after 1 h and a major part of total accumulated Cr in the intracellular (absorbed) fraction after 72 h. We also investigated the intracellular partitioning of Cr using an operational fractionation scheme and found that both Cr forms had similar distributions among fractions: Cr was mostly associated with organelles (23 ± 12% after 1 h and 37 ± 7% after 72 h) and cytosolic heat-stable proteins and peptides (39 ± 18% after 1 h and 35 ± 3% after 72 h) fractions. Further investigations using a metallomic approach (SEC-ICP-MS) were performed with the heat-stable proteins and peptides fraction to compare the distribution of the two Cr forms among various biomolecules of this fraction. One Cr-binding biomolecule (∼28 kDa) appeared after 1 h of exposure for both Cr species. After 72 h another biomolecule of lower molecular weight (∼0.7 kDa) was involved in binding Cr and higher signal intensities were observed for Cr(VI) than for Cr(III). We show, for the

Bioaccumulation and subcellular partitioning of Cr(III) and Cr(VI) in the freshwater green alga Chlamydomonas reinhardtii

International Nuclear Information System (INIS)

Aharchaou, Imad; Rosabal, Maikel; Liu, Fengjie; Battaglia, Eric; Vignati, Davide A.L.; Fortin, Claude

2017-01-01

Highlights: • C. reinhardtii accumulated similar levels of Cr(III) and Cr(VI). • The subcellular partitioning of Cr(III) and Cr(VI) was similar. • Cr(III) and Cr(VI) associated mainly with organelles and heat-stable proteins. • Metallomic analysis showed two main Cr-binding biomolecules after 72 h of exposure. - Abstract: Chromium occurs in aquatic environments under two main redox forms, namely Cr(III) and Cr(VI), with different geochemical and biochemical properties. Cr(VI) readily crosses biological membranes of living organisms and once inside the cells it undergoes a rapid reduction to Cr(III). The route of entry for the latter form is, however, poorly known. Using the radioactive tracer "5"1Cr we compared the accumulation (absorption and adsorption) of the two Cr forms by the green unicellular alga Chlamydomonas reinhardii after 1 h and 72 h of exposure to 100 nM of either Cr(III) or Cr(VI) at pH 7. Both Cr forms had similar accumulation, with a major part in the extracellular (adsorbed) fraction after 1 h and a major part of total accumulated Cr in the intracellular (absorbed) fraction after 72 h. We also investigated the intracellular partitioning of Cr using an operational fractionation scheme and found that both Cr forms had similar distributions among fractions: Cr was mostly associated with organelles (23 ± 12% after 1 h and 37 ± 7% after 72 h) and cytosolic heat-stable proteins and peptides (39 ± 18% after 1 h and 35 ± 3% after 72 h) fractions. Further investigations using a metallomic approach (SEC-ICP-MS) were performed with the heat-stable proteins and peptides fraction to compare the distribution of the two Cr forms among various biomolecules of this fraction. One Cr-binding biomolecule (∼28 kDa) appeared after 1 h of exposure for both Cr species. After 72 h another biomolecule of lower molecular weight (∼0.7 kDa) was involved in binding Cr and higher signal intensities were observed for Cr(VI) than for Cr(III). We show, for the

A mechanical and tribological study of Cr/CrN multilayer coatings

Energy Technology Data Exchange (ETDEWEB)

Arias, D.F., E-mail: diegomas@gmail.com [Grupo GEMA, Universidad Católica de Pereira, Pereira (Colombia); Gómez, A. [Laboratório de Fenômenos de Superficie, Escola Politécnica, Universidade de Sao Paulo, Sao Paulo (Brazil); Pontificia Universidad Javeriana Cali (Colombia); Vélez, J.M. [Escuela de Ingeniería de Materiales, Universidad Nacional de Colombia Sede Medellín (Colombia); Souza, R.M. [Laboratório de Fenômenos de Superficie, Escola Politécnica, Universidade de Sao Paulo, Sao Paulo (Brazil); Olaya, J.J. [Departamento de Ingeniería Mecánica y Mecatrónica, Universidad Nacional de Colombia, Bogotá (Colombia)

2015-06-15

Multilayer Cr/CrN coatings with different periodicities were grown on silicon substrates by means of a magnetron sputtering technique. Thin films with only Cr or CrN were also grown, in order to use them as reference samples. Structural, morphological, mechanical and tribological characterization were carried out by using X-ray diffraction (XRD), atomic force microscopy (AFM), nanohardness and nanoscratch techniques, respectively. The characterization results were analyzed as a function of the bilayer thickness (period). In general, the multilayer hardness value increased with the decrease in period. In addition, the validity of the Hall-Petch relationship was confirmed for grain sizes and period values greater than 146 nm and 333 nm, respectively. The coefficient of friction (COF) increased with increasing load, which indicates the contribution of the adhesion to the COF. - Highlights: • Multilayer Cr/CrN coatings with layer thickness between 200 and 1000 nm were grown. • Neither bias voltage not temperature were applied during deposition. • The hardness improves with the increase of the number of bilayers. • The wear rate decreases with the increase of the number of bilayers.

Species dependent radiotracer study of Cr(VI) and Cr(III) using an aqueous biphasic system

Energy Technology Data Exchange (ETDEWEB)

Roy, K.; Lahiri, S. [Chemical Sciences Div., Saha Inst. of Nuclear Physics, Kolkata (India)

2008-07-01

The speciation study of Cr(III) and Cr(VI) was carried out using a polyethylene glycol (PEG) based aqueous biphasic extraction system (ABS). Neutron activated Cr(III) and Cr(VI) salts were assayed in a HPGe detector before and after employing aqueous biphasic extraction. Different salts of various salting out abilities were taken as the salt rich phase. The best condition for extraction of Cr(VI) and the maximum differential attitude of ABS to Cr(VI) and Cr(III) was observed when 2 M Na{sub 2}SO{sub 4} and PEG 4000 (50% w/w) solutions were used. Cr(III) can also be extracted by the PEG with prior complexation with diphenylthiocarbazone (dithizone). The chromium dithizonate complex is quantitatively extracted by the PEG rich phase. (orig.)

Migration of Cr-vacancy clusters and interstitial Cr in α-Fe using the dimer method

International Nuclear Information System (INIS)

Chen, D.; Gao, F.; Hu, S. Y.; Sun, X.; Heinisch, H. L.; Henager, C. H.; Khaleel, M. A.; Hu, W. Y.; Terentyev, D.

2010-01-01

The migration mechanisms and the corresponding activation energies of Cr-vacancy (Cr-V) clusters and Cr interstitials in α-Fe have been investigated using the dimer and the nudged elastic-band methods. Dimer searches are employed to find the possible transition states of these defects and the lowest-energy paths are used to determine the energy barriers for migration. A substitutional Cr atom can migrate to a nearest-neighbor vacancy through an energy barrier of 0.56 eV but this simple mechanism alone is unlikely to lead to the long-distance migration of Cr unless there is a supersaturated concentration of vacancies in the system. The Cr-vacancy clusters can lead to long-distance migration of a Cr atom that is accomplished by Fe and Cr atoms successively jumping to nearest-neighbor vacancy positions, defined as a self-vacancy-assisted migration mechanism, with the migration energies ranging from 0.64 to 0.89 eV. In addition, a mixed Cr-Fe dumbbell interstitial can easily migrate through Fe lattices, with the migration energy barrier of 0.17, which is lower than that of the Fe-Fe interstitial. The on-site rotation of the Cr-Fe interstitial and Cr atom hopping from one site to another are believed to comprise the dominant migration mechanism. The calculated binding energies of Cr-V clusters are strongly dependent on the size of clusters and the concentration of Cr atoms in clusters.

Synthesis, characterization and biological evaluation of [{sup 188}Re(N)(cys{approx})(PNP)]{sup +/0} mixed-ligand complexes as prototypes for the development of {sup 188}Re(N)-based target-specific radiopharmaceuticals

Energy Technology Data Exchange (ETDEWEB)

Thieme, Stefan [Institute of Radiopharmacy, Forschungszentrum Dresden Rossendorf, P.O. Box 510 119, 01314 Dresden (Germany); Agostini, Stefania [Department of Pharmaceutical Sciences, University of Padua, Via Marzolo 5, 35131 Padova (Italy); Bergmann, Ralf; Pietzsch, Jens; Pietzsch, Hans-Juergen [Institute of Radiopharmacy, Forschungszentrum Dresden Rossendorf, P.O. Box 510 119, 01314 Dresden (Germany); Carta, Davide; Salvarese, Nicola [Department of Pharmaceutical Sciences, University of Padua, Via Marzolo 5, 35131 Padova (Italy); Refosco, Fiorenzo [ICIS-CNR, Corso Stati Uniti 4, 35127 Padova (Italy); Bolzati, Cristina, E-mail: bolzati@icis.cnr.i [Department of Pharmaceutical Sciences, University of Padua, Via Marzolo 5, 35131 Padova (Italy); ICIS-CNR, Corso Stati Uniti 4, 35127 Padova (Italy)

2011-04-15

We report on an efficient procedure for the preparation of [{sup 188}Re(N)(PNP)]-based complexes (where PNP is diphosphinoamine) useful in the development of target-specific radiopharmaceuticals. The radiochemical yield of the compounds was optimized considering such reaction parameters as nature of the nitrido nitrogen donor, reaction times and pH level. The chemical identity of the {sup 188}Re agents was determined by high-performance liquid chromatography comparison with the corresponding well-characterized cold Re compounds. {sup 188}Re(N) mixed compounds have been evaluated with regard to stability toward transchelation with GSH and degradation by serum enzymes. The clearance of selected radiocompounds from normal tissues and their in vivo stability were evaluated in rats by biodistribution and imaging studies. [{sup 188}Re(N)(cys{approx})(PNP)]{sup +/0} mixed-ligand compounds were efficiently prepared in aqueous solution from perrhenate using a multistep procedure based on the preliminary formation of the labile {sup 188}Re{sup III}-EDTA species, which easily undergo oxidation/ligand exchange reaction to afford the [{sup 188}Re{sup V{identical_to}}N]{sup 2+} core in the presence of dithiocarbazate. The final mixed-ligand compounds were obtained, at 100{sup o}C, by adding the two bidentate ligands to the buffered [{sup 188}Re{sup V{identical_to}}N]{sup 2+} solution (pH 3.2-3.6). However, a relatively high amount of cys{approx} ligand was required to obtain a quantitative radiochemical yield. The complexes were stable toward reoxidation to perrhenate and ligand exchange reactions. In vivo studies showed rapid distribution and elimination of the complexes from the body. No specific uptakes in sensitive tissues/organs were detected. A positive correlation of the distribution of the complexes estimated with biodistribution studies (%ID) and with micro-SPECT semiquantification imaging analysis (standard uptake values) was observed. These results support the

P-type Al-doped Cr-deficient CrN thin films for thermoelectrics

Science.gov (United States)

le Febvrier, Arnaud; Van Nong, Ngo; Abadias, Gregory; Eklund, Per

2018-05-01

Thermoelectric properties of chromium nitride (CrN)-based films grown on c-plane sapphire by dc reactive magnetron sputtering were investigated. In this work, aluminum doping was introduced in CrN (degenerate n-type semiconductor) by co-deposition. Under the present deposition conditions, over-stoichiometry in nitrogen (CrN1+δ) rock-salt structure is obtained. A p-type conduction is observed with nitrogen-rich CrN combined with aluminum doping. The Cr0.96Al0.04N1.17 film exhibited a high Seebeck coefficient and a sufficient power factor at 300 °C. These results are a starting point for designing p-type/n-type thermoelectric materials based on chromium nitride films, which are cheap and routinely grown on the industrial scale.

Clinical applicability of determination of serum tumor markers (CEA, CA15-3 and CA125) levels changes for assessment of efficacy of chemotherapy in patients with breast cancer

International Nuclear Information System (INIS)

Xu Junying; Liu Chaoying; Li Jiang; Hu Hong; Wang Runjie

2009-01-01

Objective: To study the usefulness of monitoring changes of serum levels of tumor markers (CEA, CA15-3 and CA125) for assessment of efficacy of chemotherapy in patients with breast cancer. Methods: Serum CEA, CA15-3 and CA125 levels were measured with CLIA three days before beginning 1st course of appropriate chemotherapy and 3 weeks after completing 2nd course of treatment in 45 patients with advanced breast cancer (TNM stage III, n=20, stage IV n=25). Results: Expressed as CR, PR, SD and PD as defined by the changes of serum tumor markers levels (according to Bac D.J. et al) were compared with clinically observed ones (WHO standard). The serum levels of Cea, CA15-3 decreased markedly in the CR and PR groups of patients but increased markedly in PD patients (P 0.05). The coincidence rate between the results observed clinically and results derived from tumor marker changes was 50.0% for CEA, 55.6% for CA15-3, 31.1% for CA125 and 73% for three markers combined. Conclusion: Combined determination of the changes of serum levels of three tumor marker would help to make a reasonably satisfactory assessment of efficacy of chemotherapy in patients with breast cancer. (authors)

Phase I trial of the androgen receptor modulator CR1447 in breast cancer patients

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Martin Zweifel

2017-09-01

Full Text Available CR1447 (4-hydroxytestosterone, 4-OHT binds to the androgen receptor and has antiproliferative activity in both ER-positive and ER-negative/AR-positive breast cancer cells in preclinical studies. The objective of this first-in man trial was to evaluate the safety and to determine the dose of CR1447, administered as an ointment, for Phase II. Escalating doses (100, 200, 400 mg of CR1447 were administered topically on a daily basis to patients with ER-positive/AR-positive/HER2-negative advanced breast cancer pretreated with several lines of therapy. 14 patients have been treated for a total of 42 cycles. Two patients, one at dose level 100 mg and one at dose level 200 mg, showed early tumour progression and were replaced. Related adverse events were all ≤ grade 2 and included fatigue, bone and joint pain, stiffness, dry skin and mouth, nausea, sweating, urinary tract infection, rash, headache and distress. No drug-related dose-limiting toxicities (DLTs were seen. Two patients (17% achieved stable disease at 3 months. Pharmacokinetic analysis confirmed dose-dependent transdermal uptake of CR1447. 4-OH-androstenedione (4-OHA, a key metabolite of 4-OHT, was undetectable in most of the plasma samples. Urine metabolites of 4-OHT and 4-OHA indicate high exposure of 4-OHT after topical administration. Oestradiol serum concentrations did not increase, confirming preclinical data that CR1447 is not converted to estrogens in vivo. In conclusion, CR1447 administered transdermally as an ointment is well tolerated and appears to have single-agent activity in heavily pretreated ER-positive/HER2-negative breast cancer patients. The recommended phase II dose is 400 mg/day.

Radioassay of granulocyte chemotaxis. Studies of human granulocytes and chemotactic factors. [/sup 51/Cr tracer technique

Energy Technology Data Exchange (ETDEWEB)

Gallin, J I

1974-01-01

The above studies demonstrate that the /sup 51/Cr radiolabel chemotactic assay is a relatively simple and objective means for studying leukocyte chemotaxis in both normal and pathological conditions. Application of this method to studies of normal human chemotaxis revealed a relatively narrow range of normal and little day-to-day variability. Analysis of this variability revealed that there is more variability among the response of different granulocytes to a constant chemotactic stimulus than among the chemotactic activity of different sera to a single cell source. Utilizing the /sup 51/Cr radioassay, the abnormal granulocyte chemotactic behavior reported in Chediak-Higashi syndrome and a patient with recurrent pyogenic infections and mucocutaneous candidiasis has been confirmed. The /sup 51/Cr chemotactic assay has also been used to assess the generation of chemotactic activity from human serum and plasma. The in vitro generation of two distinct chemotactic factors were examined; the complement product (C5a) and kallikrein, an enzyme of the kinin-generating pathway. Kinetic analysis of complement-related chemotactic factor formation, utilizing immune complexes or endotoxin to activate normal sera in the presence or absence of EGTA as well as kinetic analysis of activation of C2-deficient human serum, provided an easy means of distinguishing the classical (antibody-mediated) complement pathway from the alternate pathway. Such kinetic analysis is necessary to detect clinically important abnormalities since, after 60 min of generation time, normal chemotactic activity may be present despite complete absence or inhibition of one complement pathway. The chemotactic factor generated by either pathway of complement activation appears to be predominately attributable to C5a.

Studies of 51Cr-albumin metabolism by the method of the whole body radiometry in men

International Nuclear Information System (INIS)

Bondarenko, N.I.; Kaplan, M.A.; Bolovin, L.M.

1980-01-01

A method of investigation on metabolism of human serum 61 Cr-labelled albumin is reported. The method allows to determine albumin and plasma losses without of collecting excreta. The studies of external losses show that healthy individuals lose about 2% or 2.5 g albumin and 60-70 ml plasma a day on the average. Total plasma albumin, extravascular albumin and total metabolic albumin are calculated by means of whole-body radiometry

Cr 3d surface and bulk states in Sn1-xCrxTe/Cr crystals

International Nuclear Information System (INIS)

Guziewicz, E.; Szamota-Sadowska, K.; Kowalski, B.J.; Grodzicka, E.; Story, T.; Orlowski, B.A.; Johnson, R.L.

1997-01-01

We report a new approach to investigate metal-semiconductor interface formation. Photoemission spectroscopy was applied in order to investigate the clean surface of a Sn 0.97 Cr 0.03 Te crystal and to observe its changes under sequential deposition of small amounts of Cr atoms. In order to analyse the Cr 3d contribution to the valence band, the Fano-type resonance tuned to the Cr 3p-3d transmission was used. The experiment was designed to follow the Sn 0.97 Cr 0.03 Te/Cr interface formation process. At the clean Sn 0.97 Cr 0.03 Te surface, the Cr 3d states contribution to the valence band was found to be positioned 0.8 eV below Fermi level. After the Cr deposition processes the contribution shifted to a higher binding energy and another contribution 5.8 eV below the Fermi level also observed. (author)

Role of defects on the electronic and magnetic properties of CrAs, CrSe and CrSb zinc-blende compounds

International Nuclear Information System (INIS)

Galanakis, I.; Pouliasis, S.G.

2009-01-01

We present an extended study of single impurity atoms and atomic swaps in half-metallic CrAs, CrSb and CrSe zinc-blende compounds. Although the perfect alloys present a rather large gap in the minority-spin band, all defects under study, with the exception of void impurities at Cr and sp sites and Cr impurities at sp sites (as long as no swap occurs), induce new states within the gap. The Fermi level can be pinned within these new minority states depending on the lattice constant used for the calculations and the electronegativity of the sp atoms. Although these impurity states are localized in space around the impurity atoms and very fast we regain the bulk behavior, their interaction can lead to wide bands within the gap and thus loss of the half-metallic character

Fracture toughness and sliding properties of magnetron sputtered CrBC and CrBCN coatings

Science.gov (United States)

Wang, Qianzhi; Zhou, Fei; Ma, Qiang; Callisti, Mauro; Polcar, Tomas; Yan, Jiwang

2018-06-01

CrBC and CrBCN coatings with low and high B contents were deposited on 316L steel and Si wafers using an unbalanced magnetron sputtering system. Mechanical properties including hardness (H), elastic modulus (E) and fracture toughness (KIc) as well as residual stresses (σ) were quantified. A clear correlation between structural, mechanical and tribological properties of coatings was found. In particular, structural analyses indicated that N incorporation in CrBC coatings with high B content caused a significant structural evolution of the nanocomposite structure (crystalline grains embedded into an amorphous matrix) from nc-CrB2/(a-CrBx, a-BCx) to nc-CrN/(a-BCx, a-BN). As a result, the hardness of CrBC coating with high B content decreased from 23.4 to 16.3 GPa but the fracture toughness was enhanced. Consequently, less cracks initiated on CrBCN coatings during tribological tests, which combined with the shielding effect of a-BN on wear debris, led to a low friction coefficient and wear rate.

Use of 51Cr release to measure the cytotoxic effects of staphylococcal leukocidin and toxin neutralization on bovine leukocytes

International Nuclear Information System (INIS)

Loeffler, D.A.; Schat, K.A.; Norcross, N.L.

1986-01-01

Leukocidin toxin from Staphylococcus aureus produces specific cytolytic effects on neutrophils and macrophages. The most commonly used method for determination of leukocidin activity is microscopic examination for characteristic morphological changes in toxin-treated cells. The 51 Cr release assay was modified to allow quantitation of the cytolytic effects of leukocidin on bovine peripheral blood neutrophils and lymphocytes. Toxin neutralization by serum and milk samples was quantitated by this method. The neutralizing abilities of the various samples were found to correlate with the levels of immunoglobulin G (IgG1) specific for leukocidin. Undiluted normal serum samples, however, were capable of partially preventing the cytotoxic effects of leukocidin. The assay was shown to be an effective means of quantitating the cytotoxic activity of leukocidin on neutrophils as well as demonstrating neutralization of cytotoxicity by milk and serum samples

The Reduction of Cr(VI) to Cr(III) by Natural Fe-Bearing Minerals: A Synchrotron XAS Study

Science.gov (United States)

Xu, H.; Guo, X.; Ding, M.; Migdissov, A. A.; Boukhalfa, H.; Sun, C.; Roback, R. C.; Reimus, P. W.; Katzman, D.

2017-12-01

Cr(VI) in the form of CrO42- is a pollutant species in groundwater and soils that can pose health and environmental problems. Cr(VI) associated with use as a corrosion inhibitor at a power plant from 1956-1972 is present in a deep groundwater aquifer at Los Alamos National Laboratory. A potential remediation strategy for the Cr contamination is reduction of Cr(VI) to Cr(III) via the acceptance of electrons from naturally occurring or induced Fe(II) occurring in Fe-bearing minerals. In this work, using synchrotron-based X-ray techniques, we investigated the Cr reduction behavior by Fe-bearing minerals from outcrop and core samples representative of the contaminated portion of the aquifer. Samples were exposed to solutions with a range of known Cr (VI) concentrations. XANES and EXAFS spectra showed that all the Cr(VI) had been reduced to Cr(III), and micro XRF mapping revealed close correlation of Cr and Fe distribution, implying that Fe(II) in minerals reduced Cr(VI) in the solution. Similar behavior was observed from in-situ XANES measurements on Cr reduction and adsorption by mineral separates from the rock samples in Cr(VI)-bearing solutions. In addition, to obtain reference parameters for interpreting the data of natural samples, we collected Cr and Fe EXAFS spectra of Cr(III)-Fe(III) hydroxide solid solutions, which show progressive changes in the local structure around Cr and Fe over the whole series.

Can preoperative serum level of creatinine predict new-onset atrial fibrillation in non-diabetic male patients undergoing open heart surgery? A retrograde view.

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Seyed Jalil Mirhosseini

2013-12-01

Full Text Available Renal dysfunction is a risk marker in patients who candidate for coronary artery bypass graft (CABG. Renal disorder is associated with prolonged stays in intensive care unit and hospital, morbidity and mortality. Aim of this study is specific evaluation of association between preoperative creatinine (Cr with atrial fibrillation (AF after elective off-pump CABG in non-diabetic male patients with normal ejection fraction. Two hundred non-diabetic male patients with normal ejection fraction undergoing elective off pump CABG surgery enrolled in this cross-sectional study and were stratified by present or absence of postoperative atrial fibrillation: patients with postoperative new-onset atrial fibrillation (n=100 as group 1 and patients without new-onset postoperative atrial fibrillation as group 2 (n=100. Preoperative serological test of the participants, such as serum creatinine, were recorded in their medical dossiers. Data were analyzed in SPSS-16 software and tested for association between atrial fibrillation with creatinine level by using student t test, chi-square test or logistic regression. Cr level in patients with and without AF three days before surgery were 1.8±0.3 and 1.0±0.4 respectively (P value for Cr=0.00. On surgical day, mean Cr level in patients with and without AF were 1.6±0.2 and 1.1±0.5 respectively (P value for Cr = 0.00. Of the 100, male patients with postoperative AF, duration and frequency of recurrence of AF were not associated with Cr at three days before surgery and on surgical days (P>0.05. Patients with postoperative AF had unsuitable status of renal function compare to patients without AF; however, preoperative serum creatinine cannot associate with duration and frequency of recurrence of AF.

LaCrO{sub 3}-dispersed Cr for metallic interconnect of planar SOFC

Energy Technology Data Exchange (ETDEWEB)

Song, Rak-Hyun; Shin, Dong Ryul [Korea Institute of Energy Research, Taejon (Korea, Republic of); Dokiya, Masayuki [National Institute of Materials and Chemical Research, Ibaraki (Japan)

1996-12-31

In the planar SOFC, the interconnect materials plays two roles as an electrical connection and as a gas separation plate in a cell stack. The interconnect materials must be chemically stable in reducing and oxidizing environments, and have high electronic conductivity, high thermal conductivity, matching thermal expansion with an electrolyte, high mechanical strength, good fabricability, and gas tightness. Lanthanum chromite so far has been mainly used as interconnect materials in planar SOFC. However, the ceramic materials are very weak in mechanical strength and have poor machining property as compared with metal. Also the metallic materials have high electronic conductivity and high thermal conductivity. Recently some researchers have studied metallic interconnects such as Al{sub 2}O{sub 3}/Inconel 600 cermet, Ni-20Cr coated with (LaSr)CoO{sub 3}, and Y{sub 2}O{sub 3-} or La{sub 2}O{sub 3}-dispersed Cr alloy. These alloys have still some problems because Ni-based alloys have high thermal expansion, the added Al{sub 2}O{sub 3}, Y{sub 2}O{sub 3} and La{sub 2}O{sub 3} to metals have no electronic conductivity, and the oxide formed on the surface of Cr alloy has high volatility. To solve these problems, in this study, LaCrO{sub 3}-dispersed Cr for metallic interconnect of planar SOFC was investigated. The LaCrO{sub 3}-dispersed Cr can be one candidate of metallic interconnect because LaCrO{sub 3} possesses electronic conductivity and Cr metal has relatively low thermal expansion. The content of 25 vol.% LaCrO{sub 3} Was selected on the basis of a theoretically calculated thermal expansion. The thermal expansion, electrical and oxidation properties were examined and the results were discussed as related to SOFC requirements.

Serum Polychlorinated Biphenyls Increase and Oxidative Stress Decreases with a Protein-Pacing Caloric Restriction Diet in Obese Men and Women

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Feng He

2017-01-01

Full Text Available The purposes were to compare the effects of a: (1 12-week P-CR weight loss (WL diet (Phase 1 between obese men and women and; (2 52-week modified P-CR (mP-CR vs. heart healthy (HH weight maintenance (WM diet (Phase 2 on serum PCBs and oxidative stress biomarkers (thiobarbituric acid reactive substances, TBARS; total antioxidant capacity, TAC in 40 obese participants (men, n = 21; women, n = 19. Participants received dietary counseling and monitoring of compliance. PCBs, TBARS, and TAC were assessed at weeks −1 (CON, 12 (WL, and 64 (WM. Following WL (Week 12, concomitant with reductions in TBARS (0.24 ± 0.15 vs. 0.18 ± 0.11 µM; p < 0.01, PCB serum concentrations (86.7 ± 45.6 vs. 115.6 ± 65.9 ng/g lipid; p < 0.01 and TAC (18.9 ± 2.6 vs. 19.9 ± 2.3 nmol/mL; p < 0.02 were increased similarly in men and women. At the end of WM (Week 64, a significant effect of time × group interaction was observed for % change in PCB 170 and 187; whereby mP-CR values were higher compared to HH (PCB170: 19.31% ± 26.48% vs. −6.61% ± 28.88%, p = 0.02; PCB187: −3.04% ± 17.78% vs. −21.4% ± 27.31%, p = 0.04. PCB changes were positively correlated with TBARS levels (r > 0.42, p < 0.05 and negatively correlated with body weight, fat mass, and abdominal fat (r < −0.46, p < 0.02. Our results support mobilization of stored PCBs as well as enhanced redox status following a 12-week P-CR WL diet. Additionally, a 52-week mP-CR WM diet demonstrated an advantage in preventing weight gain relapse accompanied by an increase in circulating PCBs compared to a traditional HH diet.

Plantago lanceolata growth and Cr uptake after mycorrhizal inoculation in a Cr amended substrate

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Amaia Nogales

2012-03-01

Full Text Available Arbuscular mycorrhizal fungi from two chromium contaminated sites, one with 275 mg kg-1 of Cr (zone A and the other with 550 mg kg-1 Cr (zone B, were multiplied and tentatively identified. The effect of both fungal consortia on Plantago lanceolata plant growth in a substrate amended with 200 mg kg-1 of Cr and with 400 mg kg-1 Cr was assessed and compared with the growth of plants inoculated with Glomus intraradices BEG72. Only the plants inoculated with G. intraradices BEG72 and with the fungal consortia obtained from the area with a high Cr contamination (zone B grew in the soil with 400 mg kg-1 of Cr. The consortia of fungi from zone B, decreased the plant’s uptake/translocation of the heavy metal compared with G. intraradices BEG72. These results underscore the differential effect of AM fungi in conferring bioprotection in Cr contaminated soils.

Effect of Cr4+ impurities in Nd:Cr:GSGG and Nd:Cr:YAG laser materials on parameters of lasers at solar pumping

International Nuclear Information System (INIS)

Payziyev, Sh.D.; Bakhramov, S.A.; Shayimov, F.F.; Fayziev, A.Sh.

2015-01-01

The analysis of an effect of Cr 4+ impurity ions, existent in Nd 3+ :Cr 3+ :GSGG and Nd 3+ :Cr 3+ :YAG laser materials on output parameters of solar pumped lasers is carried out by modeling of lasing process at solar pumping. (authors)

Evaluation of multielements in human serum of patients with chronic myelogenous leukemia (CML) using SRTXRF

International Nuclear Information System (INIS)

Leitao, Catarine Canellas Gondim

2005-04-01

In this work, trace elements were analyzed in serum of patients with chronic myelogenous leukemia (CML) by Total Reflection X-Ray Fluorescence using synchrotron radiation (SRTXRF). Chronic myelogenous leukemia (CML) affects the myeloid cells in the blood and affects 1 to 2 people per 100,000 and accounts for 7-20% cases of leukemia. Sixty patients with CML and sixty healthy volunteers (control group) were studied. Blood was collected into vacutainers without additives. Directly after collection, each blood sample was centrifuged at 3000 rev/min for 10 min in order to separate blood cells and suspended particles from blood serum. Sera were transferred into polyethylene tubes and stored in a freezer at 253 K. A 500 m u L serum quantity was spiked with Ga (50 m u L ) as internal standard. 10 m u L aliquots were pipetted on Perspex sample carrier. After deposition, the samples were left to dry under an infrared lamp. The measurements were performed at the X-Ray Fluorescence Beamline at Brazilian National Synchrotron Light Laboratory (LNLS), using a polychromatic beam. Standard solutions with gallium as internal standard were prepared for calibration system. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Br and Rb. Starting from the ANOVA test was observed that the elements P, S, Ca, Cr, Mn, Fe, Cu and Rb presented real significant differences (α = 0.05) between groups (healthy subjects and CML patients) and Sex (males and females). (author)

Sintering behaviour and mechanical properties of Cr3C2–NiCr ...

Indian Academy of Sciences (India)

fracture toughness. Keywords. Cermet; Cr3C2–NiCr; sintering; mechanical properties. ... et al investigated the mechanical properties of VC, Cr3C2 and NbC doped ..... Huang S G, Li L, Van der Biest O and Vleugels J 2008 J. Alloys. Compds.

Role of serum creatinine for screening renal diseases

International Nuclear Information System (INIS)

Younas, M.; Khan, F.A.; Sattar, A.; Kazmi, A.

2011-01-01

Chronic kidney disease (CKD) is a public Heath problem with increasing prevalence in Pakistan. Early identification of mild renal disease can delay its progression. Glomerular filtration rate (GFR) is the best overall index of renal function, but it is difficult to measure, so mostly clinicians rely on. serum creatinine (SCr) concentration which its own limitations. On the other hand 24 hours (h) urinary creatinine clearance (CICl) is a more sensitive marker of renal dysfunction. Presently SCr is being used in our clinical practice to screen the renal diseases which can miss mild renal dysfunctions, so this study was designed to calculate frequency of individuals having reduced GFR as determined by CrCI having normal SCr levels. (author)

Radioimmunoassay of haloperidol in human serum: correlation of serum haloperidol with serum prolactin

International Nuclear Information System (INIS)

Poland, R.E.; Rubin, R.T.

1981-01-01

A radioimmunoassay (RIA) for measurement of serum haloperidol is described. Compared to gaschromatography (GC), RIA vaues average 40% higher. However, a simple organic extraction of serum yields statistically equivalent RIA and GC haloperidol determinations. For both men and women combined, there was a positive correlation between dose (mg/kg/day) and steady-state serum haloperidol level (r = +0.86) and between steady-state serum haloperidol and serum prolactin (PRL) concentration

Effect of azithromycin combined with fat-soluble vitamin on serum inflammatory cytokines and chemokines as well as lung function in children with mycoplasma pneumonia

Directory of Open Access Journals (Sweden)

Ming-Guang Yang1

2017-04-01

Full Text Available Objective: To study the effect of azithromycin combined with fat-soluble vitamin on serum inflammatory cytokines and chemokines as well as lung function in children with mycoplasma pneumonia. Methods: 56 children with mycoplasma pneumonia admitted in our hospital between May 2012 and May 2016 were collected, the treatment methods and laboratory test results were retrospectively analyzed, and then they were divided into the control group (n=26 who received azithromycin treatment alone and the observation group (n=30 who received fatsoluble vitamin combined with azithromycin treatment. Before treatment and after 1 week of treatment, enzyme-linked immunosorbent assay (ELISA was used to detect the serum levels of inflammatory cytokines and chemokines; lung function monitor for children was used to detect lung function index levels. Results: Before treatment, differences in serum inflammation index and chemokine contents as well as lung function indexes were not statistically significant between two groups of patients (P>0.05. After treatment, serum inflammation indexes IL-4 and IL-13 contents of observation group were lower than those of control group while IL- 10 and IL-12 contents were higher than those of control group (P<0.05; serum chemokines MCP-4, MDC and CysLTs contents of observation group were lower than those of control group (P<0.05; lung function indexes V-T, FEV1, PEF and MMEF25%-75% levels of observation group were higher than those of control group (P<0.05. Conclusion: Fat-soluble vitamin combined with azithromycin can reduce the systemic inflammatory response and optimize the lung function in children with mycoplasma pneumoniae infection.

A selective and regenerable voltammetric aptasensor for determination of homocysteine

International Nuclear Information System (INIS)

Saeed, Jaber; Mirzaei, Mohammad; Torkzadeh-Mahani, Masoud

2016-01-01

We describe an electrochemical aptasensor for the amino acid homocysteine (hCys). A gold electrode was modified with a highly specific aptamer against hCys (a 66-base DNA oligonucleotide) acting as the recognition probe. The method is highly selective over cysteine and methionine. The effects of accumulation time, type and concentration of accumulation buffer and pH, type and concentration of stripping buffer were studied. Under optimized conditions and a working potential of 1.07 V (vs. Ag/AgCl), the response to hCys is linear in the 0.2 to 10 μM concentration range. The detection limit is 10 nM, and the relative standard deviation is 3.1 % (at 1 μM of hCys). The electrode can be regenerated by immersing it into a 3 M solution of urea solution. The method was applied to the determination of hCys in (spiked) serum and urine and gave recoveries of 88.5 and 96.5 %, respectively. (author)

The 5-HT2C receptor gene Cys23Ser polymorphism influences the intravaginal ejaculation latency time in Dutch Caucasian men with lifelong premature ejaculation

NARCIS (Netherlands)

Janssen, Paddy Kc; Schaik, Ron van; Olivier, Berend|info:eu-repo/dai/nl/073067199; Waldinger, Marcel D|info:eu-repo/dai/nl/163958564

2014-01-01

It has been postulated that the persistent short intravaginal ejaculation latency time (IELT) of men with lifelong premature ejaculation (LPE) is related to 5-hydroxytryptamine (HT)2C receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2C receptor gene

Distribution of chromium species in a Cr-polluted soil: presence of Cr(III) in glomalin related protein fraction.

Science.gov (United States)

Gil-Cardeza, María L; Ferri, Alejandro; Cornejo, Pablo; Gomez, Elena

2014-09-15

The accumulation of Cr in soil could be highly toxic to human health; therefore Cr soil distribution was studied in rhizosphere soils from Ricinus communis and Conium maculatum and bare soil (BS) from an industrial and urban area in Argentina. Total Cr, Cr(VI) and Cr(III) concentrations were determined in 3 soil fractions: total, extractable and associated to total-glomalin-related protein (T-GRSP). BS had the highest total Cr and total Cr(VI) concentrations. Total Cr(VI) concentration from both rhizosphere soils did not differ from the allowed value for residential area in Argentina (8 μg Cr(VI) g(-1) soil), while total Cr(VI) in BS was 1.8 times higher. Total Cr concentration in all the soils was higher than the allowed value (250 μg Cr g(-1) soil). Extractable and associated to T-GRSP Cr(VI) concentrations were below the detection limit. Cr(III) bound to T-GRSP was the highest in the BS. These findings are in agreement with a long term effect of glomalin in sequestrating Cr. In both plant species, total Cr was higher in root than in shoot and both species presented arbuscular mycorrhizal fungi (AMF). As far as we know, this is the first study that reports the presence of Cr in T-GRSP fraction of soil organic matter. These findings suggest that Cr mycorrhizostabilization could be a predominant mechanism used by R. communis and C. maculatum to diminish Cr soil concentration. Nevertheless, further research is needed to clarify the contribution of native AMF isolated from R. communis and C. maculatum rhizosphere to the Cr phytoremediation process. Copyright © 2014 Elsevier B.V. All rights reserved.

Black Cr/α-Cr2O3 nanoparticles based solar absorbers

International Nuclear Information System (INIS)

Khamlich, S.; Nemraoui, O.; Mongwaketsi, N.; McCrindle, R.; Cingo, N.; Maaza, M.

2012-01-01

Monodisperse spherical core–shell particles of Cr/α-Cr 2 O 3 with high adhesion were successfully coated on rough copper substrates by a simple self-assembly-like method for the use in solar thermal absorbers. The structure and morphology of the core-shell particles of Cr/α-Cr 2 O 3 were effectively controlled by deposition temperature and the pH of the initial precursor solution. Their characterizations were carried out with X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry and attenuated total reflection, as well as UV–vis diffuse reflectance spectroscopy. The samples aged for more than 40 h at 75 °C exhibit the targeted high absorbing optical characteristic “Black chrome” while those aged for ≤40 h show a significant high UV–vis diffuse reflectance “green color”.

Association analysis of PON2 genetic variants with serum paraoxonase activity and systemic lupus erythematosus

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Manzi Susan

2011-01-01

Full Text Available Abstract Background Low serum paraoxonase (PON activity is associated with the risk of coronary artery disease, diabetes and systemic lupus erythematosus (SLE. Our prior studies have shown that the PON1/rs662 (p.Gln192Arg, PON1/rs854560 (p.Leu55Met, PON3/rs17884563 and PON3/rs740264 SNPs (single nucleotide polymorphisms significantly affect serum PON activity. Since PON1, PON2 and PON3 share high degree of structural and functional properties, in this study, we examined the role of PON2 genetic variation on serum PON activity, risk of SLE and SLE-related clinical manifestations in a Caucasian case-control sample. Methods PON2 SNPs were selected from HapMap and SeattleSNPs databases by including at least one tagSNP from each bin defined in these resources. A total of nineteen PON2 SNPs were successfully genotyped in 411 SLE cases and 511 healthy controls using pyrosequencing, restriction fragment length polymorphism (RFLP or TaqMan allelic discrimination methods. Results Our pair-wise linkage disequilibrium (LD analysis, using an r2 cutoff of 0.7, identified 14 PON2 tagSNPs that captured all 19 PON2 variants in our sample, 12 of which were not in high LD with known PON1 and PON3 SNP modifiers of PON activity. Stepwise regression analysis of PON activity, including the known modifiers, identified five PON2 SNPs [rs6954345 (p.Ser311Cys, rs13306702, rs987539, rs11982486, and rs4729189; P = 0.005 to 2.1 × 10-6] that were significantly associated with PON activity. We found no association of PON2 SNPs with SLE risk but modest associations were observed with lupus nephritis (rs11981433, rs17876205, rs17876183 and immunologic disorder (rs11981433 in SLE patients (P = 0.013 to 0.042. Conclusions Our data indicate that PON2 genetic variants significantly affect variation in serum PON activity and have modest effects on risk of lupus nephritis and SLE-related immunologic disorder.

Nitric oxide circulates in mammalian plasma primarily as an S-nitroso adduct of serum albumin.

Science.gov (United States)

Stamler, J S; Jaraki, O; Osborne, J; Simon, D I; Keaney, J; Vita, J; Singel, D; Valeri, C R; Loscalzo, J

1992-01-01

We have recently shown that nitric oxide or authentic endothelium-derived relaxing factor generated in a biologic system reacts in the presence of specific protein thiols to form S-nitrosoprotein derivatives that have endothelium-derived relaxing factor-like properties. The single free cysteine of serum albumin, Cys-34, is particularly reactive toward nitrogen oxides (most likely nitrosonium ion) under physiologic conditions, primarily because of its anomalously low pK; given its abundance in plasma, where it accounts for approximately 0.5 mM thiol, we hypothesized that this plasma protein serves as a reservoir for nitric oxide produced by the endothelial cell. To test this hypothesis, we developed a methodology, which involves UV photolytic cleavage of the S--NO bond before reaction with ozone for chemiluminescence detection, with which to measure free nitric oxide, S-nitrosothiols, and S-nitrosoproteins in biologic systems. We found that human plasma contains approximately 7 microM S-nitrosothiols, of which 96% are S-nitrosoproteins, 82% of which is accounted for by S-nitroso-serum albumin. By contrast, plasma levels of free nitric oxide are only in the 3-nM range. In rabbits, plasma S-nitrosothiols are present at approximately 1 microM; 60 min after administration of NG-monomethyl-L-arginine at 50 mg/ml, a selective and potent inhibitor of nitric oxide synthetases, S-nitrosothiols decreased by approximately 40% (greater than 95% of which were accounted for by S-nitrosoproteins, and approximately 80% of which was S-nitroso-serum albumin); this decrease was accompanied by a concomitant increase in mean arterial blood pressure of 22%. These data suggest that naturally produced nitric oxide circulates in plasma primarily complexed in S-nitrosothiol species, principal among which is S-nitroso-serum albumin. This abundant, relatively long-lived adduct likely serves as a reservoir with which plasma levels of highly reactive, short-lived free nitric oxide can be

Isotope Effects in the Bonds of beta-CrOOH and beta-CrOOD

DEFF Research Database (Denmark)

Nørlund Christensen, A.; Hansen, P.; Lehmann, M. S.

1976-01-01

Samples of orthorhombic chromium oxide hydroxide, beta -CrOOH, and the deuterated compound, beta -CrOOD, were prepared hydrothermally. The crystal structures were determined by powder profile refinement technique using neutron diffraction data. Unit cells are: beta -CrOOH: a equals 4. 862(2) A, b...... equals 4. 298(a) A, c equals 2. 995(1) A; beta -CrOOD: a equals 4. 873(5) A, b equals 4. 332(7) A, c equals 2. 963(2) A, with Z equals 2. The space group is P2//1nm or Pnnm....

Density of Liquid Ni-Cr Alloy

Institute of Scientific and Technical Information of China (English)

无

2003-01-01

The density of liquid Ni-Cr alloy was measured by a modified sessile drop method. The density of liquid Ni-Cr alloywas found to decrease with increasing temperature and Cr concentration in the alloy. The molar volume of liquidNi-Cr alloy increases with increasing the Cr concentration in the alloy. The molar volume of Ni-Cr alloy determinedin the present work shows a positive deviation from the linear molar volume.

Analysis of PTA hardfacing with CoCrWC and CoCrMoSi alloys

Directory of Open Access Journals (Sweden)

Adriano Scheid

2013-12-01

Full Text Available CoCrWC alloys are widely used to protect components that operate under wear and high temperature environments. Enhanced performance has been achieved with the CoCrMoSi alloys but processing this alloy system is still a challenge due to the presence of the brittle Laves phase, particularly when welding is involved. This work evaluated Plasma Transferred Arc coatings processed with the Co-based alloy CoMoCrSi - Tribaloy T400, reinforced with Laves phase, comparing its weldability to the CoCrWC - Stellite 6, reinforced with carbides. Coatings were also analyzed regarding the response to temperature exposure at 600°C for 7 days and subsequent effect on microstructure and sliding abrasive wear. Coatings characterization was carried out by light and scanning electron microscopy, X-ray diffraction and Vickers hardness. CoCrWC coatings exhibited a Cobalt solid solution dendritic microstructure and a thin interdendritic region with eutectic carbides, while CoCrMoSi deposits exhibit a large lamellar eutectic region of Laves phase and Cobalt solid solution and a small fraction of primary Laves phase. Although phase stability was observed by X-ray diffraction, coarsening of the microstructure occurred for both alloys. CoCrMoSi showed thicker lamellar Laves phase and CoCrWC coarser eutectic carbides. Coatings stability assessed by wear tests revealed that although the wear rate of the as-deposited CoCrMoSi alloy was lower than that of CoCrWC alloy its increase after temperature exposure was more significant, 22% against 15%. Results were discussed regarding the protection of industrial components in particular, bearings in 55AlZn hot dip galvanizing components.

Femtosecond Cr:LiSAF and Cr:LiCAF lasers pumped by tapered diode lasers.

Science.gov (United States)

Demirbas, Umit; Schmalz, Michael; Sumpf, Bernd; Erbert, Götz; Petrich, Gale S; Kolodziejski, Leslie A; Fujimoto, James G; Kärtner, Franz X; Leitenstorfer, Alfred

2011-10-10

We report compact, low-cost and efficient Cr:Colquiriite lasers that are pumped by high brightness tapered laser diodes. The tapered laser diodes provided 1 to 1.2 W of output power around 675 nm, at an electrical-to-optical conversion efficiency of about 30%. Using a single tapered diode laser as the pump source, we have demonstrated output powers of 500 mW and 410 mW together with slope efficiencies of 47% and 41% from continuous wave (cw) Cr:LiSAF and Cr:LiCAF lasers, respectively. In cw mode-locked operation, sub-100-fs pulse trains with average power between 200 mW and 250 mW were obtained at repetition rates around 100 MHz. Upon pumping the Cr:Colquiriite lasers with two tapered laser diodes (one from each side of the crystal), we have observed scaling of cw powers to 850 mW in Cr:LiSAF and to 650 mW in Cr:LiCAF. From the double side pumped Cr:LiCAF laser, we have also obtained ~220 fs long pulses with 5.4 nJ of pulse energy at 77 MHz repetition rate. These are the highest energy levels reported from Cr:Colquiriite so far at these repetition rates. Our findings indicate that tapered diodes in the red spectral region are likely to become the standard pump source for Cr:Colquiriite lasers in the near future. Moreover, the simplified pumping scheme might facilitate efficient commercialization of Cr:Colquiriite systems, bearing the potential to significantly boost applications of cw and femtosecond lasers in this spectral region (750-1000 nm).

Comparison of serum oxidant and antioxidant parameters in familial Mediterranean fever patients (FMF) with attack free period.

Science.gov (United States)

Şahin, Ali; Erten, Şükran; Altunoğlu, Alpaslan; Işıkoğlu, Semra; Neşelioğlu, Salim; Ergin, Merve; Atalay, Hacı Veli; Erel, Özcan

2014-01-01

Familial Mediterranean fever (FMF) is an autoinflammatory, autosomal recessive, inherited disease characterized by recurrent self-limiting attacks of serosal surfaces. The imbalance of oxidants/antioxidants may play a role in such attacks. In this study, we aimed to evaluate the relationship between serum paraoxonase (PON1) activity, PON1 phenotype, and other parameters in patients with FMF and healthy controls. A total of 120 FMF patients with an attack-free period (AFP) and 65 healthy subjects were included in this study. The serum PON1 activity, stimulated paraoxonase (SPON) activity, PON1 phenotype (representing Q192R polymorphism; QQ, QR, RR), arylesterase activity, total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI), advanced oxidative protein products (AOPP), total thiols (TTL), and ischemia-modified albumin (IMA) and cystatin-c (CYS-C) levels were measured. For the QQ phenotype, the median TTL and AOPP levels of the control group were 264.50 (57.75) mol/L and 21.26 (21.17) mmol/L, respectively, whereas the median TTL, AOPP levels of the patients were 309.00 (47.00) mol/L and 12.98 (6.96) mmol/L, respectively. There was a statistically significant difference between the patients and controls with the QQ phenotype in terms of TTL and AOPP (pantioxidant parameters were similar among the patients during AFP and the controls.

Study on the correlation of Cys C and blood lipid with diabetic retinopathy%血清胱抑素C及血脂水平与糖尿病视网膜病变的关系研究

Institute of Scientific and Technical Information of China (English)

赖静怡; 张颖栩; 黄焕葵

2015-01-01

Abstract•AlM:To study the correlation of Cys C and blood lipid with diabetic retinopathy ( DR) .•METHODS:Sixty patients with DR from June 2011 to December 2014 were selected. According to international criteria, in the patients with DR, there were 28 cases without remarkable DR, 22 cases with mild, middle and sever nonproliferative diabetic retinopathy ( NPDR ) , 10 cases with proliferative diabetic retinopathy ( PDR ) . Sixty diabetic patients without DR were selected as NDR group. Sixty healthy people were selected as control group. Cys C, triglyceride ( TG) and total cholesterol ( TC) were detected.•RESULTS:ln DR group, Cys C, TG and TC levels were higher than those in the NDR group and the control group, while in NDR group Cys C, TG and TC levels were higher than thoes in the control group, and the difference was statistically significant (P< 0. 05). As DR aggravating, Cys C increased, and the difference was statistically significant (P<0. 05). Cys C were positively correlated with the duration and blood lipid level (P<0. 05).•CONCLUSlON:Cys C changes abnormally in patients with DR, and with the progress of DR, Cys C trends to increase. The abnormal changes in DR patients positively associated with dyslipidemia.%目的：：探讨糖尿病视网膜病变( diabetic retinopathy, DR)患者胱抑素C、血脂水平及相关性。方法：选取2011-06/2014-12 DR患者60例为研究对象。根据DR国际分期无明显视网膜病变的28例,轻、中、重非增生性视网膜病变22例,增生性糖尿病视网膜病变10例。选择60例糖尿病无视网膜病变患者为疾病对照组( NDR组)；选择60例健康者为健康对照组。检测受试者胱抑素C、甘油三酯及总胆固醇水平。结果：DR组胱抑素 C、甘油三酯及总胆固醇水平高于NDR组和健康对照组,而NDR组高于健康对照组,差异有统计学意义(P<0.05)；随着DR病变程度的加重,胱抑素 C水平呈增加趋势,差异有统计学意义(P<0.05)�

Factor VII Tokushima: the first case of factor VII Cys22Gly with the development of myocardial infarction in the proband receiving recombinant factor VIIa replacement therapy.

Science.gov (United States)

Shigekiyo, Toshio; Sekimoto, Etsuko; Shibata, Hironobu; Ozaki, Shuji; Okumura, Takanobu; Fujinaga, Hiroyuki; Shibata, Hiroshi; Aihara, Ken-ichi; Akaike, Masashi

2015-12-01

An 81-year-old man was referred to our department because of suspected factor VII (FVII) deficiency. His FVII activity was under 1%, whereas the FVII activity levels of his son and granddaughter were 65 and 109%, respectively. The nucleotide at position 3886 of his FVII gene was homozygous for G. A single T to G substitution results in the replacement of wild-type Cys at residue 22 by Gly. His son was heterozygous for G and T at position 3886, whereas his granddaughter was homozygous for wild-type T. These results suggest that he was homozygous for FVII Cys22Gly. He underwent radiofrequency ablation (RFA) for hepatocellular carcinoma, receiving 20 μg/kg of recombinant FVIIa prior to RFA and 10 μg/kg of recombinant FVIIa twice after RFA. He showed no bleeding tendency; however, a myocardial infarction was diagnosed and percutaneous coronary intervention was performed.

Microstructure and Mechanical Characterization of a Dissimilar Friction-Stir-Welded CuCrZr/CuNiCrSi Butt Joint

Directory of Open Access Journals (Sweden)

Youqing Sun

2018-05-01

Full Text Available Dissimilar CuNiCrSi and CuCrZr butt joints were successfully frictionstirwelded at constant welding speed of 150 mm/min and rotational speed of 1400 rpm with the CuCrZr alloy or the CuNiCrSi alloy located on the advancing side (AS. The microstructure and mechanical properties of joints were investigated. When the CuCrZr alloy was located on the AS, the area of retreating material in the nugget zone was a little bigger. The Cr solute-rich particles were found in the nugget zone on CuCrZr side (CuCrZr-NZ while a larger density of solute-rich particles identified as the concentration of Cr and Si element was found in the nugget zone on CuNiCrSi side (CuNiCrSi-NZ. The Cr precipitates and δ-Ni2Si precipitates were found in the base metal on CuNiCrSi side (CuNiCrSi-BM but only Cr precipitates can be observed in the base metal on CuCrZr side (CuCrZr-BM. Precipitates were totally dissolved into Cu matrix in both CuCrZr-NZ and CuNiCrSi-NZ, which led to a sharp decrease in both micro-hardness and tensile strength from BM to NZ. When the CuNiCrSi was located on the AS, the tensile testing results showed the fracture occurred at the CuCrZr-NZ, while the fracture was found at the mixed zone of CuNiCrSi-NZ and CuCrZr-NZ for the other case.

53Cr NMR study of CuCrO2 multiferroic

Science.gov (United States)

Smol'nikov, A. G.; Ogloblichev, V. V.; Verkhovskii, S. V.; Mikhalev, K. N.; Yakubovskii, A. Yu.; Kumagai, K.; Furukawa, Y.; Sadykov, A. F.; Piskunov, Yu. V.; Gerashchenko, A. P.; Barilo, S. N.; Shiryaev, S. V.

2015-11-01

The magnetically ordered phase of the CuCrO2 single crystal has been studied by the nuclear magnetic resonance (NMR) method on 53Cr nuclei in the absence of an external magnetic field. The 53Cr NMR spectrum is observed in the frequency range νres = 61-66 MHz. The shape of the spectrum depends on the delay tdel between pulses in the pulse sequence τπ/2- t del-τπ- t del-echo. The spin-spin and spin-lattice relaxation times have been measured. Components of the electric field gradient, hyperfine fields, and the magnetic moment on chromium atoms have been estimated.

Heterogeneity of Cr in Mytilus edulis: Implications for the Cr isotope system as a paleo-redox proxy

Science.gov (United States)

Bruggmann, Sylvie; Klaebe, Robert; Frei, Robert

2017-04-01

Changes in 53Cr/52Cr (δ53Cr) values recorded by biogenic carbonates are emerging as a proxy for variations in the redox state of the Earth's oceans and atmosphere (e.g. [1], [2]). We investigate the ability of modern carbonate shells (Mytilus edulis) to record the δ53Cr composition of ambient seawater in order to assess their utility as a paleo-redox proxy. Samples of cultivated M. edulis from the Kiel Fjord, Germany, were analyzed for their δ53Cr composition and Cr concentrations [Cr] using TIMS. To disentangle the pathway of Cr into the carbonate shell, a series of step-digestions of their organic outer sheaths (periostraca) and their intra-layer composition were performed. Bulk analyses of specimens with intact periostraca returned 16 to 34 ppb Cr with δ53Cr values ranging from 0.28 to 0.65 ± 0.1 (2SE) and thus fall within the range of surface seawater from the Baltic Sea (0.3 - 0.6 \\permil [3]). Partial removal of periostraca resulted in lower [Cr] (5 to 17 ppb) and δ53Cr values (-0.05 ± 0.15 \\permil). These results show a positive correlation between the amount of organic matter present in a sample and both [Cr] and δ53Cr (n = 9). With nearly complete removal of periostraca, the remaining [Cr] is significantly lower (less than 5 ppb) and can only be accessed by incineration of the carbonate shell. The correlation between [Cr], δ53Cr and the amount of periostracum present in bulk samples indicates that a significant proportion of preserved Cr may be associated with the organic outer sheath. The Cr endmember accessed after incineration is less likely associated with the carbonate crystal lattice. Instead, the δ53Cr values obtained after incineration are similar to those reported from terrestrial rocks, suggesting the influence of detrital particles. Alternatively, Cr may be reduced and subsequently re-oxidized during the mineralization of biogenic carbonates [4]. Seasonal changes in primary productivity in seawater may further influence the shell

Study on Tribological Properties of CoCrMo Alloys against Metals and Ceramics as Bearing Materials for Artificial Cervical Disc

Science.gov (United States)

Xiang, Dingding; Song, Jian; Wang, Song; Liao, Zhenhua; Liu, Yuhong; Tyagi, Rajnesh; Liu, Weiqiang

2018-02-01

CoCrMo alloys are believed to be a kind of potential material for artificial cervical disc. However, the tribological properties of CoCrMo alloys against different metals and ceramics are not systematically studied. In this study, the tribological behaviors of CoCrMo alloys against metals (316L, Ti6Al4V) and ceramics (Si3N4, ZrO2) were focused under dry friction and 25 wt.% newborn calf serum (NCS)-lubricated conditions using a ball-on-disc apparatus under reciprocating motion. The microstructure, composition and hardness of CoCrMo alloys were characterized using x-ray diffraction, scanning electron microscopy (SEM) and hardness testers, respectively. The contact angles of the CoCrMo alloys with deionized water and 25 wt.% NCS were measured by the OCA contact angle measuring instrument. The maximum wear width, wear depth and wear volume were measured by three-dimensional white light interference. The morphology and the EDX analysis of the wear marks on CoCrMo alloys were examined by SEM to determine the basic mechanism of friction and wear. The dominant wear mechanism in dry friction for CoCrMo alloys against all pairings was severe abrasive wear, accompanied with a lot of material transfer. Under 25 wt.% NCS-lubricated condition, the wear mechanism for CoCrMo alloys against ceramics (Si3N4, ZrO2) was also mainly severe abrasive wear. However, severe abrasive wear and electrochemical corrosion occurred for the CoCrMo-316L pairing under lubrication. Severe abrasive wear, adhesive wear and electrochemical corrosion occurred for the CoCrMo-Ti6Al4V pairing under lubrication. According to the results, the tribological properties of CoCrMo alloys against ceramics were better than those against metals. The CoCrMo-ZrO2 pairing displayed the best tribological behaviors and could be taken as a potential candidate bearing material for artificial cervical disc.

Determination of toxic and essential trace elements in serum of healthy and hypothyroid respondents by ICP-MS: A chemometric approach for discrimination of hypothyroidism.

Science.gov (United States)

Stojsavljević, Aleksandar; Trifković, Jelena; Rasić-Milutinović, Zorica; Jovanović, Dragana; Bogdanović, Gradimir; Mutić, Jelena; Manojlović, Dragan

2018-07-01

Inductively coupled plasma-mass spectrometry ((ICP-MS)) was used to determine three toxic (Ni, As, Cd) and six essential trace elements (Cr, Mn, Co, Cu, Zn, Se) in blood serum of patients with hypothyroidism (Hy group) and healthy people (control group), in order to set the experimental conditions for accurate determination of a unique profile of these elements in hypothyroidism. Method validation was performed with standard reference material of the serum by varying the sample treatment with both standard and collision mode for analysis of elements isotopes. Quadratic curvilinear functions with good performances of models and the lowest detection limits were obtained for 52 Cr, 66 Zn, 75 As, 112 Cd in collision mode, and 55 Mn, 59 Co, 60 Ni, 65 Cu, 78 Se in standard mode. Treatment of serum samples with aqueous solution containing nitric acid, Triton X-100 and n-butanol gave the best results. Chemometric tools were applied for discrimination of patients with hypothyroidism. All nine elements discriminated Hy group of samples with almost the same discriminating power as indicated by their higher values for this group of patients. Statistically significant correlation (p hypothyroid state. Copyright © 2018 Elsevier GmbH. All rights reserved.

Identification of a novel BRCA1 nucleotide 4803delCC/c.4684delCC mutation and a nucleotide 249T>A/c.130T>A (p.Cys44Ser) mutation in two Greenlandic Inuit families

DEFF Research Database (Denmark)

Hansen, Thomas van Overeem; Jønson, Lars; Albrechtsen, Anders

2010-01-01

Germ-line mutations in the tumour suppressor proteins BRCA1 and BRCA2 predispose to breast and ovarian cancer. We have recently identified a Greenlandic Inuit BRCA1 nucleotide 234T>G/c.115T>G (p.Cys39Gly) founder mutation, which at that time was the only disease-causing BRCA1/BRCA2 mutation...... identified in this population. Here, we describe the identification of a novel disease-causing BRCA1 nucleotide 4803delCC/c.4684delCC mutation in a Greenlandic Inuit with ovarian cancer. The mutation introduces a frameshift and a premature stop at codon 1572. We have also identified a BRCA1 nucleotide 249T......>A/c.130T>A (p.Cys44Ser) mutation in another Greenlandic individual with ovarian cancer. This patient share a 1-2 Mb genomic fragment, containing the BRCA1 gene, with four Danish families harbouring the same mutation, suggesting that the 249T>A/c.130T>A (p.Cys44Ser) mutation originates from a Danish...

Kinetic stable Cr isotopic fractionation between aqueous Cr(III)-Cl-H2O complexes at 25 °C: Implications for Cr(III) mobility and isotopic variations in modern and ancient natural systems

Science.gov (United States)

Babechuk, Michael G.; Kleinhanns, Ilka C.; Reitter, Elmar; Schoenberg, Ronny

2018-02-01

The stable Cr isotope fractionation preserved in natural substances has been attributed predominantly to Cr(III)-Cr(VI) redox transformations. However, non-redox reaction pathways (e.g., ligand-promoted dissolution, ligand exchange, adsorption of Cr(III)) are liable to contribute to isotopic fractionation in natural systems given that soluble Cr(III)-ligands have been directly documented or modeled in several marine, continental, and hydrothermal environments. This study isolates the stable Cr isotope fractionation accompanying Cl-H2O ligand exchange during the transformation of three aqueous species in the Cr(III)-Cl-H2O system, [CrCl2(H2O)4]+aq (abr. CrCl2+ or S1), [CrCl(H2O)5]2+aq (abr. CrCl2+ or S2), and [Cr(H2O)6]3+aq (abr. Cr3+ or S3), at low pH (≤2). In dilute HCl (0.01 to 1 M), Cr3+ is the kinetically favoured species and transformation of CrCl2+ to CrCl2+ to Cr3+ via 2 steps of dechlorination/hydrolyzation begins immediately upon dissolution of a Cr(III)-Cl solid. Individual species are separated with cation exchange chromatography at different stages of transformation and inter- and intra-species (across an elution peak of one species) isotopic fractionation of up to 1 and 2‰ (δ53/52Cr), respectively, is documented. Comparison of peak elution characteristics with Cr-Cl-H-O isotopologue mass abundances suggests mass-dependent sorting of isotopologues alone cannot explain intra-species fractionation, supporting a previously published proposal that preferential adsorption of light Cr isotopes on the resin is driven by vibrational energy effects. The transformation of CrCl2+ to CrCl2+ is faster than CrCl2+ to Cr3+ and the rates of both transformations increase with solution pH. Preferential reaction of light Cr(III) isotopes into product species occurs during each transformation, consistent with closed-system, kinetic fractionation during Cl-H2O ligand exchange. Inter-species fractionation is assessed using time-series experiments beginning from the

Reduction of Cr(VI) to Cr(III) using silicon nanowire arrays under visible light irradiation

Energy Technology Data Exchange (ETDEWEB)

Fellahi, Ouarda [Institut d' Electronique, de Microélectronique et de Nanotechnologie (IEMN), UMR CNRS 8520, Avenue Poincaré—BP 70478, 59652 Villeneuve d' Ascq Cedex (France); Centre de Recherche en Technologie des Semi-conducteurs pour l' Energétique-CRTSE 02, Bd Frantz Fanon, BP. 140, Alger 7 Merveilles (Algeria); Barras, Alexandre [Institut d' Electronique, de Microélectronique et de Nanotechnologie (IEMN), UMR CNRS 8520, Avenue Poincaré—BP 70478, 59652 Villeneuve d' Ascq Cedex (France); Pan, Guo-Hui [State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 3888 Dong Nanhu Road, Changchun 130033 (China); Coffinier, Yannick [Institut d' Electronique, de Microélectronique et de Nanotechnologie (IEMN), UMR CNRS 8520, Avenue Poincaré—BP 70478, 59652 Villeneuve d' Ascq Cedex (France); Hadjersi, Toufik [Centre de Recherche en Technologie des Semi-conducteurs pour l' Energétique-CRTSE 02, Bd Frantz Fanon, BP. 140, Alger 7 Merveilles (Algeria); Maamache, Mustapha [Laboratoire de Physique Quantique et Systèmes Dynamiques, Département de Physique, Université de Sétif, Sétif 19000 (Algeria); Szunerits, Sabine [Institut d' Electronique, de Microélectronique et de Nanotechnologie (IEMN), UMR CNRS 8520, Avenue Poincaré—BP 70478, 59652 Villeneuve d' Ascq Cedex (France); and others

2016-03-05

Highlights: • Cr(VI) reduction to Cr(III) using silicon nanowires decorated with Cu nanoparticles. • The reduction takes place at room temperature and neutral pH under visible light. • The photocatalytic reduction was enhanced by addition of adipic or citric acid. - Abstract: We report an efficient visible light-induced reduction of hexavalent chromium Cr(VI) to trivalent Cr(III) by direct illumination of an aqueous solution of potassium dichromate (K{sub 2}Cr{sub 2}O{sub 7}) in the presence of hydrogenated silicon nanowires (H-SiNWs) or silicon nanowires decorated with copper nanoparticles (Cu NPs-SiNWs) as photocatalyst. The SiNW arrays investigated in this study were prepared by chemical etching of crystalline silicon in HF/AgNO{sub 3} aqueous solution. The Cu NPs were deposited on SiNW arrays via electroless deposition technique. Visible light irradiation of an aqueous solution of K{sub 2}Cr{sub 2}O{sub 7} (10{sup −4} M) in presence of H-SiNWs showed that these substrates were not efficient for Cr(VI) reduction. The reduction efficiency achieved was less than 10% after 120 min irradiation at λ > 420 nm. Addition of organic acids such as citric or adipic acid in the solution accelerated Cr(VI) reduction in a concentration-dependent manner. Interestingly, Cu NPs-SiNWs was found to be a very efficient interface for the reduction of Cr(VI) to Cr(III) in absence of organic acids. Almost a full reduction of Cr(VI) was achieved by direct visible light irradiation for 140 min using this photocatalyst.

A strain-variable bacteriocin in Bacillus anthracis and Bacillus cereus with repeated Cys-Xaa-Xaa motifs

Directory of Open Access Journals (Sweden)

Haft Daniel H

2009-04-01

Full Text Available Abstract Bacteriocins are peptide antibiotics from ribosomally translated precursors, produced by bacteria often through extensive post-translational modification. Minimal sequence conservation, short gene lengths, and low complexity sequence can hinder bacteriocin identification, even during gene calling, so they are often discovered by proximity to accessory genes encoding maturation, immunity, and export functions. This work reports a new subfamily of putative thiazole-containing heterocyclic bacteriocins. It appears universal in all strains of Bacillus anthracis and B. cereus, but has gone unrecognized because it is always encoded far from its maturation protein operon. Patterns of insertions and deletions among twenty-four variants suggest a repeating functional unit of Cys-Xaa-Xaa. Reviewers This article was reviewed by Andrei Osterman and Lakshminarayan Iyer.

THE EFFECT OF RARE EARTH ELEMENTS ON Cr PRECIPITATIONS IN A Cu-0.8WT%Cr ALLOY

Directory of Open Access Journals (Sweden)

Gewang Shuai

2011-05-01

Full Text Available The microstructural evolution of Cu-based alloys during aging was studied using a quantitative metallographic method. Samples were cut from ingots of Cu-0.8wt%Cr and Cu-0.8wt%Cr-RE alloys. These were solution treated at 1000 ºC for 1.5h and subsequently quenched in water, then separately aged at 480 ºC for different durations. The microstructures were observed by optical microscope, and the characteristic geometric parameters of precipitated Cr phase, including volume fraction VV, face density NA, mean diameter and roundness, were measured. These data provided more details about the process of aging. The results showed that precipitation of Cr phase occurred in the form of particles during aging. Rare earth elements promoted the precipitation of Cr phase and dispersed Cr particles. The phenomenon of overaging came earlier in Cu-Cr-RE than in Cu-Cr. In the present work, the optimal aging time at 480 ºC was 2 hrs for the Cu-0.8wt%Cr-RE alloy and 3 hours for the Cu-0.8wt%Cr alloy.

Serum Polychlorinated Biphenyls Increase and Oxidative Stress Decreases with a Protein-Pacing Caloric Restriction Diet in Obese Men and Women.

Science.gov (United States)

He, Feng; Zuo, Li; Ward, Emery; Arciero, Paul J

2017-01-10

The purposes were to compare the effects of a: (1) 12-week P-CR weight loss (WL) diet (Phase 1) between obese men and women and; (2) 52-week modified P-CR (mP-CR) vs. heart healthy (HH) weight maintenance (WM) diet (Phase 2) on serum PCBs and oxidative stress biomarkers (thiobarbituric acid reactive substances, TBARS; total antioxidant capacity, TAC) in 40 obese participants (men, n = 21; women, n = 19). Participants received dietary counseling and monitoring of compliance. PCBs, TBARS, and TAC were assessed at weeks -1 (CON), 12 (WL), and 64 (WM). Following WL (Week 12), concomitant with reductions in TBARS (0.24 ± 0.15 vs. 0.18 ± 0.11 µM; p 0.42, p < 0.05) and negatively correlated with body weight, fat mass, and abdominal fat ( r < -0.46, p < 0.02). Our results support mobilization of stored PCBs as well as enhanced redox status following a 12-week P-CR WL diet. Additionally, a 52-week mP-CR WM diet demonstrated an advantage in preventing weight gain relapse accompanied by an increase in circulating PCBs compared to a traditional HH diet.

Structural, electrical, and dielectric properties of Cr doped ZnO thin films: Role of Cr concentration

Energy Technology Data Exchange (ETDEWEB)

Gürbüz, Osman, E-mail: osgurbuz@yildiz.edu.tr; Okutan, Mustafa

2016-11-30

Highlights: • Magnetic material of Cr and semiconductor material of ZnO were grown by the magnetron sputtering co-sputter technique. • Perfect single crystalline structures were grown. • DC and AC conductivity with dielectric properties as a function of frequency (f = 5Hz–13 MHz) at room temperature were measured and compared. • Cr doped ZnO can be used in microwave, sensor and optoelectronic devices as the electrical conductivity increases while dielectric constant decreases with the Cr content. - Abstract: An undoped zinc oxide (ZnO) and different concentrations of chromium (Cr) doped ZnO Cr{sub x}ZnO{sub 1−x} (x = 3.74, 5.67, 8.10, 11.88, and 15.96) thin films were prepared using a magnetron sputtering technique at room temperature. These films were characterized by X-ray diffraction (XRD), High resolution scanning electron microscope (HR-SEM), and Energy dispersive X-ray spectrometry (EDS). XRD patterns of all the films showed that the films possess crystalline structure with preferred orientation along the (100) crystal plane. The average crystallite size obtained was found to be between 95 and 83 nm which was beneficial in high intensity recording peak. Both crystal quality and crystallite sizes decrease with increasing Cr concentration. The crystal and grain sizes of the all film were investigated using SEM analysis. The surface morphology that is grain size changes with increase Cr concentration and small grains coalesce together to form larger grains for the Cr{sub 11.88}ZnO and Cr{sub 15.96}ZnO samples. Impedance spectroscopy studies were carried out in the frequencies ranging from 5 Hz to 13 MHz at room temperature. The undoped ZnO film had the highest dielectric value, while dielectric values of other films decreased as doping concentrations increased. Besides, the dielectric constants decreased whereas the loss tangents increased with increasing Cr content. This was considered to be related to the reduction of grain size as Cr content in Zn

Modeling on Fe-Cr microstructure: evolution with Cr content

International Nuclear Information System (INIS)

Diaz Arroyo, D.; Perlado, J.M.; Hernandez-Mayoral, M.; Caturla, M.J.; Victoria, M.

2007-01-01

Full text of publication follows: The minimum energy configuration of interstitials in the Fe-Cr system, which is the base for the low activation steels being developed in the European fusion reactor materials community, is determined by magnetism. Magnetism plays also a role in the atomic configurations found with increasing Cr content. Results will be presented from a program in which the microstructure evolution produced after heavy ion irradiation in the range from room temperature to 80 K is studied as a function of the Cr content in alloys produced under well controlled conditions, i.e. from high purity elements and with adequate heat treatment. It is expected that these measurements will serve as matrix for model validation. The first step in such modeling sequence is being performed by modeling the evolution of displacement cascades in Fe using the Dudarev -Derlet and Mendeleev potentials for Fe and the Caro potential for Fe-Cr. It is of particular interest to study the evolution of high-energy cascades, where an attempt will be made to clarify the role of the evolution of sub-cascades. Kinetic Monte Carlo (kMC) techniques will be used then to simulate the defect evolution. A new parallel kMC code is being implemented for this purpose. (authors)

crRNA biogenesis

NARCIS (Netherlands)

Charpentier, E.; Oost, van der J.; White, M.

2013-01-01

Mature crRNAs are key elements in CRISPR-Cas defense against genome invaders. These short RNAs are composed of unique repeat/spacer sequences that guide the Cas protein(s) to the cognate invading nucleic acids for their destruction. The biogenesis of mature crRNAs involves highly precise processing

Reduced CD300LG mRNA tissue expression, increased intramyocellular lipid content and impaired glucose metabolism in healthy male carriers of Arg82Cys in CD300LG

DEFF Research Database (Denmark)

Støy, Julie; Kampmann, Ulla; Mengel, Annette

2015-01-01

BACKGROUND: CD300LG rs72836561 (c.313C>T, p.Arg82Cys) has in genetic-epidemiological studies been associated with the lipoprotein abnormalities of the metabolic syndrome. CD300LG belongs to the CD300-family of membrane-bound molecules which have the ability to recognize and interact with extracel......BACKGROUND: CD300LG rs72836561 (c.313C>T, p.Arg82Cys) has in genetic-epidemiological studies been associated with the lipoprotein abnormalities of the metabolic syndrome. CD300LG belongs to the CD300-family of membrane-bound molecules which have the ability to recognize and interact...... with extracellular lipids. We tested whether this specific polymorphism results in abnormal lipid accumulation in skeletal muscle and liver and other indices of metabolic dysfunction. METHODS: 40 healthy men with a mean age of 55 years were characterized metabolically including assessment of insulin sensitivity...

Enhancement strategies for Cu(II), Cr(III) and Cr(VI) remediation by a variety of seaweed species.

Science.gov (United States)

Murphy, V; Hughes, H; McLoughlin, P

2009-07-15

Various chemical treatments have been applied to six brown, red and green seaweed species with a view to enhancing their metal removal for Cu(II), Cr(III) and Cr(VI). Treatment with acetone resulted in the greatest enhancement for both cationic and anionic species with relatively low mass losses (15-35%), indicating its low risk to biomass operational stability. Cation binding was increased by 69%, while the total Cr removal was augmented by 15%. Cr(VI) binding was shown to be an adsorption-coupled reduction, whereby Cr(VI) was bound to the biomass surface at pH 2 and subsequently reduced to Cr(III). Acetone treatment also resulted in biomasses that were capable of converting up to 83% of Cr(VI) in solution to Cr(III). Blocking of carboxyl and amino functionalities had significant negative effects both on total Cr removal as well as percentage conversion of Cr(VI) to Cr(III). Results therefore indicated the significant role played by these moieties in metal binding to these seaweeds. Potentiometric titrations displayed agreement between the degree of esterification and the decrease in Cu(II) removal for Ulva spp. and Polysiphonia lanosa. FTIR analysis identified changes in biomass functionality and availability after chemical modification, the results of which were in agreement with metal removal studies. In conclusion, these biosorbents represent suitable candidates to replace conventional removal technologies for metal bearing wastewaters, in particular for the detoxification of hazardous Cr(VI) waste streams.

The effect of magnetic ordering on the giant magnetoresistance of Cr-Fe-V and Cr-Fe-Mn

International Nuclear Information System (INIS)

Somsen, Ch.; Acet, M.; Nepecks, G.; Wassermann, E.F.

2000-01-01

Cr-rich Cr 1-x Fe x alloys with compositions in the vicinity of mixed ferromagnetic and antiferromagnetic exchange (x=0.18) exhibit giant magnetoresistance. In order to understand the influence of the antiferromagnetism of Cr on the giant magnetoresistance one can manipulate the antiferromagnetic exchange either by adding vanadium, which destroys the antiferromagnetism of Cr, or by adding manganese, which enhances it. Cr-Fe-V and Cr-Fe-Mn alloys also have Curie temperatures that lie between low temperatures and room temperature in the concentration region where giant magnetoresistance is observed. Therefore, they are also used as samples to study the magnetoresistance as a function of the strength of FM exchange. We discuss these points in the light of temperature and concentration-dependent magnetoresistance experiments on Cr 0.99-x Fe x V 0.01 , Cr 0.96-x Fe x V 0.04 , Cr 0.90-x Fe x Mn 0.10 and Cr 0.55 Fe x Mn 0.45-x alloys. Results indicate that the most favorable condition for a large magnetoresistance in these alloys occurs at temperatures near the Curie temperature

Effects of alloying and temperature on the high-temperature oxidation of Cr-Cr{sub 2}Nb

Energy Technology Data Exchange (ETDEWEB)

Tortorelli, P.F.; DeVan, J.H. [Oak Ridge National Lab., TN (United States); Carson, L.J. [Lincoln Univ., PA (United States)

1993-06-01

Effects of alloying additions and temperature on isothermal and cyclic oxidation resistance of Cr-Cr{sub 2}Nb alloys were examined for air exposures. An isothermal exposure temperature of 1100C led to rapid reaction of binary Cr-12 at.% Nb as manifested a high oxidation rate and nonprotective behavior. Generally parabolic kinetics, complicated by some isothermal scale cracking, were observed at 900--1000C. Scale damage was exacerbated by thermal cycling. The addition of 8 at.% Al to Cr-12 at.% Nb did not effect cyclic oxidation resistance, but there was some evidence that scale adherence on Cr-6 at.% Nb-8 at.% Al was better than that for binary Cr-6 at.% Nb. Alloying additions of Al (up to 18 at.%) or Re (2 at.%) did not improve the isothermal oxidation resistance of Cr-12 at.% Nb. However, the tendency for scale damage during both isothermal and thermal cycling exposures suggests that alloying additions that specifically improve scale plasticity or modify growth stresses could be effective for Cr-Nb alloys. 10 refs, 9 figs, 1 tab.

Blood pressure levels in male carriers of Arg82Cys in CD300LG

DEFF Research Database (Denmark)

Støy, Julie; Grarup, Niels; Hørlyck, Arne

2014-01-01

found to be associated with fasting HDL-cholesterol and triglyceride levels. The polymorphism has not been detected in hypertension GWAS potentially due to its low frequency, but CD300LG has been linked to blood pressure as CD300LG knockout mice have changes in blood pressure. Twenty......-four-hour ambulatory blood pressure was obtained in human CD300LG CT-carriers to follow up on these observations. METHODS: Twenty healthy male CD300LG rs72836561 CT-carriers matched for age and BMI with 20 healthy male CC-carriers. Office blood pressure, 24-hour ambulatory blood pressure, carotid intima......-media thickness (CIMT), and fasting blood samples were evaluated. The clinical study was combined with a genetic-epidemiological study to replicate the association between blood pressure and CD300LG Arg82Cys in 2,637 men and 3,249 women. RESULTS: CT-carriers had a higher 24-hour ambulatory systolic blood pressure...

Alloying effect on hardening of martensite stainless steels of the Fe-Cr-Ni and Fe-Cr-Co systems

International Nuclear Information System (INIS)

Fel'dgandler, Eh.G.; Savkina, L.Ya.

1975-01-01

The effect of alloying elements is considered on the γ → a-transformation and hardening of certain compositions of the ternary Fe-Cr-Ni- and Fe-Cr-Co alloy systems with the martensite structure. In martensite Fe-(10 to 14)% Cr base steels the elements Co, Cu, W, Ni, Mo, Si, Cr decrease, Mn, Si, Mo, Cu increase, and Cr, Ni, Co decrease the temperature of α → γ-transition. The tempering of martensite steels of the Fe-Cr-Ni- and Fe-Cr-Co-systems containing 10 to 14% Cr, 4 to 9% Ni, and 7 to 12% Co does not lead to hardening. Alloyage of the martensite Fe-Cr-Ni-, Fe-Cr-Co- and Fe-Cr-Ni-Co base separately with Mo, W, Si or Cu leads to a hardening during tempering, the hardening being the higher, the higher is the content of Ni and, especially, of Co. The increase in the content of Mo or Si produces the same effect as the increase in the Co content. In on Fe-Cr-Co or Fe-Cr-Ni-Co based steels alloyed with Mo or Si, two temperature ranges of ageing have been revealed which, evidently, have different hardening natures. The compositions studied could serve as the base material for producing maraging stainless steels having a complex variety of properties

Adsorption of Cr(VI and Speciation of Cr(VI and Cr(III in Aqueous Solutions Using Chemically Modified Chitosan

Directory of Open Access Journals (Sweden)

ChunYuan Tao

2012-05-01

Full Text Available A new type of grafting chitosan (CTS was synthesized using 2-hydroxyethyl- trimethyl ammonium chloride (HGCTS. The adsorption of Cr(VI on HGCTS was studied. The effect factors on adsorption and the adsorption mechanism were considered. The results indicated that the HGCTS could concentrate and separate Cr(VI at pH 4.0; the adsorption equilibrium time was 80 min; the maximum adsorption capacity was 205 mg/g. The adsorption isotherm and kinetics were investigated, equilibrium data agreed very well with the Langmuir model and the pseudo second-order model could describe the adsorption process better than the pseudo first-order model. A novel method for speciation of Cr(VI and Cr(III in environmental water samples has been developed using HGCTS as adsorbent and FAAS as determination means. The detection limit of this method was 20 ng/L, the relatively standard deviation was 1.2% and the recovery was 99%~105%.

Effect of free Cr content on corrosion behavior of 3Cr steels in a CO2 environment

Science.gov (United States)

Li, Wei; Xu, Lining; Qiao, Lijie; Li, Jinxu

2017-12-01

The corrosion behavior of 3Cr steels with three microstructures (martensite, bainite, combined ferrite and pearlite) in simulated oil field formation water with a CO2 partial pressure of 0.8 MPa was investigated. The relationships between Cr concentrations in corrosion scales and corrosion rates were studied. The precipitated phases that contained Cr were observed in steels of different microstructures, and free Cr content levels were compared. The results showed that steel with the martensite microstructure had the highest free Cr content, and thus had the highest corrosion resistance. The free Cr content of bainite steel was lower than that of martensite steel, and the corrosion rate of bainite steel was higher than that of martensite steel. Because large masses of Cr were combined in ferrite and pearlite steel, the corrosion rates of ferrite and pearlite steel were the highest. Free Cr content in steel affects its corrosion behavior greatly.

Diverse anaerobic Cr(VI) tolerant bacteria from Cr(VI)-contaminated 100H site at Hanford

Science.gov (United States)

Chakraborty, R.; Phan, R.; Lam, S.; Leung, C.; Brodie, E. L.; Hazen, T. C.

2007-12-01

Hexavalent Chromium [Cr(VI)] is a widespread contaminant found in soil, sediment, and ground water. Cr(VI) is more soluble, toxic, carcinogenic, and mutagenic compared to its reduced form Cr(III). In order to stimulate microbially mediated reduction of Cr(VI), a poly-lactate compound HRC was injected into the chromium contaminated aquifers at site 100H at Hanford. Based on the results of the bacterial community composition using high-density DNA microarray analysis of 16S rRNA gene products, we recently investigated the diversity of the dominant anaerobic culturable microbial population present at this site and their role in Cr(VI) reduction. Positive enrichments set up at 30°C using specific defined anaerobic media resulted in the isolation of an iron reducing isolate strain HAF, a sulfate reducing isolate strain HBLS and a nitrate reducing isolate, strain HLN among several others. Preliminary 16S rDNA sequence analysis identifies strain HAF as Geobacter metallireducens, strain HLN as Pseudomonas stutzeri and strain HBLS as a member of Desulfovibrio species. Strain HAF isolated with acetate as the electron donor utilized propionate, glycerol and pyruvate as alternative carbon sources, and reduced metals like Mn(IV) and Cr(VI). Growth was optimal at 37°C, pH of 6.5 and 0% salinity. Strain HLN isolated with lactate as electron donor utilized acetate, glycerol and pyruvate as alternative carbon sources, and reduced metals like Mn(IV) and Cr(VI). Optimal growth was observed at 37°C, at a pH of 7.5 and 0.3% salinity. Anaerobic active washed cell suspension of strain HLN reduced almost 95 micromolar Cr(VI) within 4 hours relative to controls. Further, with 100 micromolar Cr(VI) as the sole electron acceptor, cells of strain HLN grew to cell numbers of 4.05X 107/ml over a period of 24hrs after an initial lag, demonstrating direct enzymatic Cr(VI) reduction by this species. 10mM lactate served as the sole electron donor. These results demonstrate that Cr

Elaboration, characterization of CrN- based coatings

International Nuclear Information System (INIS)

Tlili, B.; Nouveau, C.; Guillemot, G.

2011-01-01

Cr, CrN and CrAlN monolayers were synthesized by RF dual magnetron sputtering on AISI4140 steel and silicon substrates at 200 deg. C. Multilayers coatings based on the three mono-layers such as CrN/CrAlN and Cr/CrN/CrAlN were also synthesized only on Si. The physico-chemical and mechanical properties of the layers were determined by AFM, SEM+WDS, stress, roughness and nanoindentation measurements. The influence of the thickness on the mechanical properties of the monolayers stresses has been studied and as a consequence we compared the mono and multilayers stress state.

Bicarbonate catalysis of exchange synthesis of [51Cr]Cr(III)-EDTA and other chromium complexes

International Nuclear Information System (INIS)

Aronson, F.L.; Strashun, A.M.; Lopez, C.; Steigman, J.

1993-01-01

Exchange syntheses of trivalent chromium complexes often require heating, thus limiting tagging of heat-sensitive biological compounds with 51 Cr. Bicarbonate at pH 6, accelerates the formation of mM Cr-EDTA. Accordingly, room temperature catalysis with [ 51 Cr]Cr(III) at 10 -7 -10 -8 M was investigated. Complexes were successfully formed with EDTA and iminodiacetic acid (electrophoretic analysis) and acetylacetone and tropolone (analyzed by chloroform extraction). The formation of these complexes normally requires extensive heating. (author)

Oxidation study of Cr-Ru hard coatings

Energy Technology Data Exchange (ETDEWEB)

Chen, Yung-I, E-mail: yichen@mail.ntou.edu.tw; Kuo, Yu-Chu; Chen, Sin-Min

2012-01-01

Cr-Ru alloy coatings with Cr content ranging from 47 to 83 at.% were deposited at 400 Degree-Sign C by direct current magnetron co-sputtering with a Ti interlayer on silicon substrates. With a total input power of 300 W, the Cr content in the Cr-Ru coatings increased linearly with the increasing input power of Cr. The intermetallic compound phase Cr{sub 2}Ru with columnar structure was identified for the as-deposited Cr{sub 56}Ru{sub 44} and Cr{sub 65}Ru{sub 35} coatings, resulting in an increase of hardness up to 15-16 GPa. To evaluate the performance of Cr-Ru coatings as a protective coating on glass molding dies, the annealing treatment was conducted at 600 Degree-Sign C in a 50 ppm O{sub 2}-N{sub 2} atmosphere. The outward diffusion and preferential oxidization of Cr in the Cr-Ru coatings resulted in the variations of the crystalline structure, chemical composition distribution, and surface hardness after annealing. X-ray diffraction and transmission electron microscopy (TEM) proved that an oxide scale consisting of Cr{sub 2}O{sub 3} formed on the free surface. Scanning electron microscopy and TEM observed the surface morphology and structural variation. The chemical composition depth profiles were analyzed by Auger electron microscopy, verifying the presence of a Cr-depleted zone beneath the oxide scale. The hardness of Cr{sub 56}Ru{sub 44} and Cr{sub 65}Ru{sub 35} coatings decreased to 11-12 GPa after annealing, accompanied by the replacement of the Cr{sub 2}Ru phase by the Ru phase. - Highlights: Black-Right-Pointing-Pointer We prepared crystalline Cr-Ru alloy coatings by direct current magnetron sputtering. Black-Right-Pointing-Pointer Cr-Ru coatings were annealed at 600 Degree-Sign C for 2 h in a 50 ppm O{sub 2}-N{sub 2} atmosphere. Black-Right-Pointing-Pointer Cr diffused outwardly and oxidized to form a stable and protective oxide scale. Black-Right-Pointing-Pointer The original columnar grains recrystallized to polycrystalline grains.

CysLT1 receptor-induced human airway smooth muscle cells proliferation requires ROS generation, EGF receptor transactivation and ERK1/2 phosphorylation

Directory of Open Access Journals (Sweden)

Capra Valérie

2006-03-01

Full Text Available Abstract Background Cysteine-containing leukotrienes (cysteinyl-LTs are pivotal inflammatory mediators that play important roles in the pathophysiology of asthma, allergic rhinitis, and other inflammatory conditions. In particular, cysteinyl-LTs exert a variety of effects with relevance to the aetiology of asthma such as smooth muscle contraction, eosinophil recruitment, increased microvascular permeability, enhanced mucus secretion and decreased mucus transport and, finally, airway smooth muscle cells (ASMC proliferation. We used human ASMC (HASMC to identify the signal transduction pathway(s of the leukotriene D4 (LTD4-induced DNA synthesis. Methods Proliferation of primary HASMC was measured by [3H]thymidine incorporation. Phosphorylation of EGF receptor (EGF-R and ERK1/2 was assessed with a polyclonal anti-EGF-R or anti-phosphoERKl/2 monoclonal antibody. A Ras pull-down assay kit was used to evaluate Ras activation. The production of reactive oxygen species (ROS was estimated by measuring dichlorodihydrofluorescein (DCF oxidation. Results We demonstrate that in HASMC LTD4-stimulated thymidine incorporation and potentiation of EGF-induced mitogenic signaling mostly depends upon EGF-R transactivation through the stimulation of CysLT1-R. Accordingly, we found that LTD4 stimulation was able to trigger the increase of Ras-GTP and, in turn, to activate ERK1/2. We show here that EGF-R transactivation was sensitive to pertussis toxin (PTX and phosphoinositide 3-kinase (PI3K inhibitors and that it occurred independently from Src activity, despite the observation of a strong impairment of LTD4-induced DNA synthesis following Src inhibition. More interestingly, CysLT1-R stimulation increased the production of ROS and N-acetylcysteine (NAC abolished LTD4-induced EGF-R phosphorylation and thymidine incorporation. Conclusion Collectively, our data demonstrate that in HASMC LTD4 stimulation of a Gi/o coupled CysLT1-R triggers the transactivation of the EGF

Detection and prognostic impact of renal dysfunction in patients with chronic heart failure and normal serum creatinine.

Science.gov (United States)

Scrutinio, Domenico; Passantino, Andrea; Lagioia, Rocco; Santoro, Daniela; Cacciapaglia, Erasmo

2011-03-03

Accurate identification of renal dysfunction (RD) is crucial to risk stratification in chronic heart failure (CHF). Patients with CHF are at special risk of having RD despite normal serum creatinine (SCr), owing to a decreased Cr generation. At low levels of SCr, the equations estimating renal function are less accurate. This study was aimed to assess and compare the prognostic value of formulas estimating renal function in CHF patients with normal SCr. We studied 462 patients with systolic CHF and normal SCr. Creatinine clearance was estimated by the Cockcroft-Gault (eCrCl) and glomerular filtration rate by the 4-variable MDRD equation (eGFR); eCrCl normalized for body-surface area (eCrCl(BSA)) was calculated. The primary outcome was all-cause mortality at 2 years. Seventy five patients died. At multivariate Cox regression analysis, only eCrCl(BSA) was significantly associated with mortality (p = 0.006); eGFR (p = 0.24), eCrCl (p = 0.09) and BUN (p = 0.14) were not statistically significant predictors. The patients in the lowest eCrCl(BSA) quartile had an adjusted 2.1-fold (CI: 1.06-4.1) increased risk of mortality, compared with those in the referent quartile. Two-year survival was 70.4% in the lowest eCrCl(BSA) quartile and 89.7% in the referent quartile. Other independent predictors of mortality were ischemic etiology (RR: 2.16 [CI: 1.3-3.5], p = 0.0017), NYHA III/IV class (RR: 2.45 [CI: 1.51-3.97], p = 0.0003), LVEF high-risk subgroup and can more accurately be identified by the CG formula corrected for BSA than the MDRD. Copyright © 2009 Elsevier B.V. All rights reserved.

Cr(VI) and Cr(III) removal from aqueous solution by raw and modified lignocellulosic materials: a review.

Science.gov (United States)

Miretzky, P; Cirelli, A Fernandez

2010-08-15

In aqueous systems, chromium usually exists in both trivalent and hexavalent oxidation states, being Cr(VI) of particular importance and concern due to its great toxicity. Industrial sources of Cr(VI) are leather tanning, mining of chrome ore, production of steel and alloys, etc. The most common conventional method for Cr(VI) removal is reduction to Cr(III) at pH 2.0 and precipitation of Cr (OH)(3) with lime at pH 9-10. The disadvantage of precipitation is the disposal of the solid waste. Adsorption of Cr by different low cost materials seems to be a suitable choice for wastewater treatment. Many by-products of agriculture have proved to be suitable low cost adsorbents for Cr(VI) and Cr(III) removal from water. Lignocellulosic residues, which include both wood residues and agricultural residues, have adsorption capacity comparable to other natural sorbents, but they have the advantage of very low or no cost, great availability and simple operational process. This study is a review of the recent literature on the use of natural and modified lignocellulosic residues for Cr adsorption. The Cr maximum adsorption capacity and the adsorption mechanism under different experimental conditions are reported when possibly. Copyright 2010 Elsevier B.V. All rights reserved.

Low-field spin dynamics of Cr₇Ni and Cr₇Ni-Cu-Cr₇Ni molecular rings as detected by μsR

OpenAIRE

Sanna, S.; Arosio, P.; Bordonali, L.; Adelnia, F.; Mariani, M.; Garlatti, E.; Baines, C.; Amato, A.; Sabareesh, K. P.V.; Timco, G.; Winpenny, R. E.P.; Blundell, S. J.; Lascialfari, A.

2017-01-01

Muon spin rotation measurements were used to investigate the spin dynamics of heterometallic Cr7Ni and Cr7Ni-Cu-Cr7Ni molecular clusters. In Cr7Ni the magnetic ions are arranged in a quasiplanar ring and interact via an antiferromagnetic exchange coupling constant J, while Cr7Ni-Cu-Cr7Ni is composed of two Cr7Ni linked by a bridging moiety containing one Cu ion, that induces an inter-ring ferromagnetic interaction J ≪ J. The longitudinal muon relaxation rate λ collected at low magnetic fields...

Atomistic simulation of the influence of Cr on the mobility of the edge dislocation in Fe(Cr) alloys

International Nuclear Information System (INIS)

Hafez Haghighat, S.M.; Terentyev, D.; Schaeublin, R.

2011-01-01

In this work Fe-Cr compounds, as model alloys for the ferritic base steels that are considered as main candidates for the structural materials of the future fusion reactors, are studied using molecular dynamics simulations. The Cr or so-called α' precipitates, which are obstacles to dislocations, affect mechanical properties, leading to hardening and loss of ductility. The flow stress to move an edge dislocation in a Cr solid solution in pure Fe is studied as a function of Cr content. The strength of a nanometric Cr precipitate as obstacle to an edge dislocation in pure Fe is investigated as a function of its Cr content. Results show that with increasing Cr content the precipitate obstacle strength increases, with a strong sensitivity to the local atomic order. Temperature induces a monotonic decrease of the flow stress of the Cr solid solution and of the Cr precipitate obstacle strength.

Fabrication and characterization of reference 9Cr and 12Cr-ODS low activation ferritic/martensitic steels

Energy Technology Data Exchange (ETDEWEB)

Muroga, T., E-mail: muroga@nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Nagasaka, T. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Li, Y.; Abe, H. [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Ukai, S. [Graduate School of Engineering, Hokkaido University, N13, W8, Kita-ku, Sapporo 060-8628 (Japan); Kimura, A. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Okuda, T. [Kobelco Research Institute, 1-5-5 Takatsukadai, Nishi-ku, Kobe, Hyogo 651-2271 (Japan)

2014-10-15

For the purpose of arranging reference alloys available for various characterization efforts by Japanese fusion research groups, fabrication of reference 9Cr and 12Cr-ODS steels have been carried out with similar manufacturing processes followed by various characterizations. The fabrication proceeded with powder mixing, MA, encapsulation into mild steel cases, hot extrusion and hot forging, followed by final heat treatments. Each alloy was extruded into three bars. The characterization included chemical composition analysis, SEM and TEM microstructural observations, hardness tests, tensile tests at RT and 973 K, and relatively short-term thermal creep tests at 973 K. Room temperature hardness for 9Cr-ODS was larger than 12Cr-ODS, the former showing large increase when annealing temperature exceeded 1200 K and the latter showing no significant change with annealing temperature. Tensile strength of 9Cr-ODS was significantly larger than that of 12Cr-ODS at RT but comparable at 973 K. 9Cr-ODS showed longer and shorter creep rupture time than 12Cr-ODS at high and low stress levels, respectively. The mechanism of the difference in creep properties of the two alloys was discussed.

Development of Cr3C2-25(Ni20Cr) nanostructured coatings

International Nuclear Information System (INIS)

Cunha, Cecilio Alvares da

2012-01-01

This study is divided in two parts. The first part is about the preparation of nanostructured Cr 3 C 2 -25(Ni20Cr) powders by high energy milling followed by characterization of the milled and the as received powder. Analyses of some of the data obtained were done using a theoretical approach. The second part of this study is about the preparation and characterization of coatings prepared with the nanostructured as well as the as received Cr 3 C 2 -25(Ni20Cr) powders. The high temperature erosion-oxidation (E-O) behavior of the coatings prepared with the two types of powders has been compared based on a technological approach. The average crystallite size of the Cr 3 C 2 -25(Ni20Cr) powder decreased rapidly from 145 nm to 50 nm in the initial stages of milling and thereafter decreased slowly to a steady state value of around 10 nm with further increase in milling time. This steady state corresponds to the beginning of a dynamic recovery process. The maximum lattice strain (ε = 1,17%) was observed in powders milled for 16 hours, and this powders critical crystallite size was 28 nm. In contrast, the lattice parameter attained a minimum for powders milled for 16 hours. Upon reaching the critical crystallite size, the dislocation density attained a steady state regime and all plastic deformation introduced in the material there after was in the form of events occurring at the grain boundaries, due mainly to grain boundary sliding. The deformation energy stored in the crystal lattice of the Cr 3 C 2 -25(Ni20Cr) powders milled for different times was determined from enthalpy variation measurements. These results indicated that the maximum enthalpy variation (δH = 722 mcal) also occurred for powders milled for 16 hours. In a similar manner, the maximum specific heat variation (δC p = 0,278 cal/gK) occurred for powders milled for 16 hours. The following mechanical properties of Cr 3 C 2 -25(Ni20Cr) coatings prepared using the HVOF thermal spray process were determined

Searching for “LiCrIIPO4”

International Nuclear Information System (INIS)

Mosymow, E.; Glaum, R.; Kremer, R.K.

2014-01-01

The two new phosphates LiCr II 4 (PO 4 ) 3 and Li 5 Cr II 2 Cr III (PO 4 ) 4 are discovered as equilibrium phases (ϑ=800 °C) in the quarternary system Li/Cr/P/O. Their crystal structures have been determined from single-crystal X-ray diffraction data (LiCr II 4 (PO 4 ) 3 : violet-blue, Pnma (no. 62), Z=4, a=6.175(1) Å, b=14.316(3) Å, c=10.277(2) Å, 100 parameters, R 1 =0.028, wR 2 =0.08, 2060 unique reflections with F o >4σ(F o ); Li 5 Cr II 2 Cr III (PO 4 ) 4 : greyish-green, P1 ¯ (no. 2), Z=1, a=4.9379(7) Å, b=7.917(2) Å, c=8.426(2) Å, α=109.98(2)°, β=90.71(1)°, γ=104.91(1)°, 131 parameters, R 1 =0.022, wR 2 =0.067, 1594 unique reflections with F o >4σ(F o )). Li 5 Cr II 2 Cr III (PO 4 ) 4 adopts an hitherto unknown structure type. The crystal structure of LiCr II 4 (PO 4 ) 3 is isotypic to that of NaCd II 4 (PO 4 ) 3 and related to that of the mineral silicocarnotite Ca 5 (PO 4 ) 2 (SiO 4 ). Significant disorder between Li + and Cr 2+ is observed for both crystal structures. The oxidation states assigned to chromium in these two phosphates are in agreement with UV/vis/NIR absorption spectra and magnetic susceptibility data recorded for both compounds. Instead of “LiCr II PO 4 ” mixtures of LiCr II 4 (PO 4 ) 3 , Li 5 Cr II 2 Cr III (PO 4 ) 4 , Cr 2 O 3 , and CrP are observed at equilibrium. Instead of “Li 2 Cr II P 2 O 7 ” four-phase mixtures consisting of Li 9 Cr III 3 (P 2 O 7 ) 3 (PO 4 ) 2 , Li 3 Cr III 2 (PO 4 ) 3 , LiCrP 2 O 7 , and CrP were obtained. - Graphical abstract: Investigations on the equilibrium relations in the system Li/Cr/P/O revealed the two hitherto unknown phosphates Li 5 Cr II 2 Cr III (PO 4 ) 4 and LiCr II 4 (PO 4 ) 3 . They form instead of “LiCr II PO 4 ”. The crystal structures, magnetic behavior and optical spectra of these phosphates are reported. - Highlights: • The two new phosphates Li 5 Cr II 2 Cr III (PO 4 ) 4 and LiCr II 4 (PO 4 ) 3 have been characterized. • Optical spectra and paramagnetism of

In the absence of endogenous mouse apolipoprotein E, apolipoprotein E*2(Arg-158 → Cys) transgenic mice develop more severe hyperlipoproteinemia than apolipoprotein E*3-Leiden transgenic mice

NARCIS (Netherlands)

Vlijmen, B.J.M. van; Dijk, K.W. van; Hof, H.B. van 't; Gorp, P.J.J. van; Zee, A. van der; Boom, H. van der; Breuer, M.L.; Hofker, M.H.; Havekesf, L.M.

1996-01-01

Apolipoprotein E*2(Arg-155 → Cys) (APOE*2) transgenic mice were generated and compared to the previously generated apolipoprotein E*3- Leiden (APOE*3-Leiden) transgenic mice to study the variable expression of hyperlipoproteinemia associated with these two APOE variants. In the presence of the

Plasma lipoproteins in familial dysbetalipoproteinemia associated with apolipoproteins E2 (Arg158 -->Cys), E3-Leiden, and E2 (Lys146-->Gln), and effects of treatment with simvastatin

NARCIS (Netherlands)

Zhao, S.P.; Smelt, A.H.; Maagdenberg, A.M. van den; Tol, A. van; Vroom T.F.; Gevers Leuven, J.A.; Frants, R.R.; Havekes, L.M.; Laarse, A. van der; Hooft, F.M. van 't

1994-01-01

Using a density-gradient ultracentrifugation technique, we analyzed in detail the plasma lipoprotein profiles of 18 patients with familial dysbetalipoproteinemia (FD) who had apolipoprotein (apo) E2(Arg158-->Cys) homozygosity (the E2-158 variant, n = 6), apoE3-Leiden heterozygosity (the E3-Leiden

The effect of microstructure and temperature on the oxidation behavior of two-phase Cr-Cr2X (X=Nb,Ta) alloys

International Nuclear Information System (INIS)

Brady, M.P.; Tortorelli, P.F.

1998-01-01

The oxidation behavior of Cr(X) solid solution (Cr ss ) and Cr 2 X Laves phases (X = Nb, Ta) was studied individually and in combination at 950--1,100 C in air. The Cr ss phase was significantly more oxidation resistant than the Cr 2 X Laves phase. At 950 C, two-phase alloys of Cr-Cr 2 Nb and Cr-Cr 2 Ta exhibited in-situ internal oxidation, in which remnants of the Cr 2 X Laves phase were incorporated into a growing chromia scale. At 1,100 C, the Cr-Cr 2 Nb alloys continued to exhibit in-situ internal oxidation, which resulted in extensive O/N penetration into the alloy ahead of the alloy-scale interface and catastrophic failure during cyclic oxidation. IN contrast, the Cr-Cr 2 Ta alloys exhibited a transition to selective Cr oxidation and the formation of a continuous chromia scale. The oxidation mechanism is interpreted in terms of multiphase oxidation theory

Determination of Cr(VI) in wood specimen: A XANES study at the Cr K edge

International Nuclear Information System (INIS)

Strub, E.; Plarre, R.; Radtke, M.; Reinholz, U.; Riesemeier, H.; Schoknecht, U.; Urban, K.; Juengel, P.

2008-01-01

The content of chromium in different oxidation states in chromium-treated wood was studied with XANES (X-ray absorption near-edge structure) measurements at the Cr K absorption edge. It could be shown that wood samples treated with Cr(VI) (pine and beech) did still contain a measurable content of Cr(VI) after four weeks conditioning. If such wood samples were heat exposed for 2 h with 135 deg. C prior conditioning, Cr(VI) was no longer detected by XANES, indicating a complete reduction to chromium (III)

Development of the dentistry alloy Ni-Cr-Nb; Desenvolvimento de ligas odontologicas Ni-Cr-Nb

Energy Technology Data Exchange (ETDEWEB)

Souza, M.A.; Ramos, A.S.; Hashimoto, T.M., E-mail: mari_sou@hotmail.co [UNESP/FEG, Guaratingueta, SP (Brazil). Fac. de Engenharia. Dept. de Materiais e Tecnologia

2010-07-01

This work reports on the structural characterization of Ni-Cr-Mo and Ni-Cr-Nb alloys produced by arc melting. Samples were characterized by means of optical microscopy, X-ray diffraction, scanning electron microscopy, and EDS analysis. Results indicated that the arc melting process was efficient to produce homogeneous structures in Ni-Cr-Mo and Ni-Cr-Nb alloys. The nickel dissolved large amounts of Cr, Mo and Nb, which was detected by EDS analysis and X-ray diffraction. The alloy containing molybdenum indicated the presence of structure based on Ni{sub SS}, while that the alloys containing niobium presented primary grains of Ni{sub SS} and precipitates formed by the simultaneous transformation of the Ni and Ni{sub 3}Nb phases. (author)

Oxidation resistance of CrN/(Cr,V)N hard coatings deposited by DC magnetron sputtering

Energy Technology Data Exchange (ETDEWEB)

Panjan, P., E-mail: peter.panjan@ijs.si [Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Drnovšek, A.; Kovač, J.; Gselman, P. [Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Bončina, T. [University of Maribor, Faculty of Mechanical Engineering, Smetanova 17, 2000 Maribor (Slovenia); Paskvale, S.; Čekada, M.; Kek Merl, D.; Panjan, M. [Jožef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

2015-09-30

In recent years vanadium-doped hard coatings have become available as possible candidates for self-lubrication at high temperatures. Their low coefficient of friction has mainly been attributed to the formation of the V{sub 2}O{sub 5} phase. However, the formation of vanadium oxides must be controlled by the out-diffusion of vanadium in order to achieve the combination of a low coefficient of friction and good mechanical properties for the protective coatings. In this work the application of a nanolayer of CrN/(Cr,V)N hard coating was proposed as a way to better control the out-diffusion of vanadium, while the topmost chromium oxide layer acts as barrier for the vanadium diffusion. However, the aim of this investigation was not only to focus on the formation of the oxide layer. Special attention was given to the oxidation process that takes place at the growth defects, where we observed a strong diffusion of vanadium taking place. The CrN/(Cr,V)N nanolayer coatings were deposited by DC unbalanced magnetron sputtering in an CC800/9 (CemeCon) industrial unit. The vanadium concentration in the (Cr,V)N layers was varied in the range 1.0–11.5 at.%. - Highlights: • Oxidation processes of CrN/(Cr,V)N nanolayers with vanadium content were investigated. • The CrN/(Cr,V)N hard layers were oxidized at high temperature in O2 atm. • The top chromium oxide layer acts as a diffusion barrier for vanadium ions during oxidation. • Important role of growth defects during the oxidation process is demonstrated.

Oxidation resistance of CrN/(Cr,V)N hard coatings deposited by DC magnetron sputtering

International Nuclear Information System (INIS)

Panjan, P.; Drnovšek, A.; Kovač, J.; Gselman, P.; Bončina, T.; Paskvale, S.; Čekada, M.; Kek Merl, D.; Panjan, M.

2015-01-01

In recent years vanadium-doped hard coatings have become available as possible candidates for self-lubrication at high temperatures. Their low coefficient of friction has mainly been attributed to the formation of the V_2O_5 phase. However, the formation of vanadium oxides must be controlled by the out-diffusion of vanadium in order to achieve the combination of a low coefficient of friction and good mechanical properties for the protective coatings. In this work the application of a nanolayer of CrN/(Cr,V)N hard coating was proposed as a way to better control the out-diffusion of vanadium, while the topmost chromium oxide layer acts as barrier for the vanadium diffusion. However, the aim of this investigation was not only to focus on the formation of the oxide layer. Special attention was given to the oxidation process that takes place at the growth defects, where we observed a strong diffusion of vanadium taking place. The CrN/(Cr,V)N nanolayer coatings were deposited by DC unbalanced magnetron sputtering in an CC800/9 (CemeCon) industrial unit. The vanadium concentration in the (Cr,V)N layers was varied in the range 1.0–11.5 at.%. - Highlights: • Oxidation processes of CrN/(Cr,V)N nanolayers with vanadium content were investigated. • The CrN/(Cr,V)N hard layers were oxidized at high temperature in O2 atm. • The top chromium oxide layer acts as a diffusion barrier for vanadium ions during oxidation. • Important role of growth defects during the oxidation process is demonstrated.

A crítica feminista na mira da crítica A crítica feminista na mira da crítica

Directory of Open Access Journals (Sweden)

Rita Terezinha Schmidt

2008-04-01

Full Text Available This essay presents a dialogue with some texts that appeared in an anthology of critical writings about “Brazilian feminisms,” problematizing them and thus providing a productive discussion about the production of knowledge about and by feminist criticism in Brazil. Este artigo apresenta um diálogo com textos presentes em uma antologia crítica sobre “feminismos brasileiros”, problematizando-os e, por conseguinte, gerando uma discussão produtiva acerca da produção de conhecimento sobre e pela crítica feminista no Brasil.

Is CR39 worth the effort?

International Nuclear Information System (INIS)

Griffith, R.V.

1987-01-01

CR39 proton sensitive track detectors were greeted by the radiation protection community at the end of the last decade as a major breakthrough for personnel neutron dosimetry. A number of laboratories eagerly began research on application of CR39 to their dosimetry needs. However, in the last two or three years the enthusiasm has subsided, and many health physicists have stopped working with the material. The number of participants using CR39 in the Oak Ridge National Laboratory Personnel Intercomparison Studies dropped from six in 1985 to three in 1986. On a national level, the Federal Republic of Germany with researchers active in CR39 research recently adopted an albedo system as their national standard. In contrast, the United States Department of Energy (DOE) is supporting development of a CR39 based combination dosimeter to meet Department wide dosimetry needs. The English National Radiological Protection Board (NRPB) now features the use of CR39 in the NRPB PADC(CR39). There has obviously been a range of experiences with CR39 in the dosimetry community. Why has this been the case, and what is the proper role for CR39 in personnel neutron dosimetry. 12 refs., 2 figs., 1 tab

Electronic and magnetic properties of SmCrSb3 and GdCrSb3: A first principles study

International Nuclear Information System (INIS)

Sandeep; Ghimire, M.P.; Thapa, R.K.

2011-01-01

The density of states (DOS) and the magnetic moments of SmCrSb 3 and GdCrSb 3 have been studied by first principles full-potential linearized augmented plane wave (FP-LAPW) method based on density functional theory (DFT). For the exchange-correlation potential, the local-spin density approximations with correlation energy (LSDA+U) method have been used. Total and partial DOS have been computed using the WIEN2k code. DOS result shows the exchange-splittings of Cr-3d and rare-earth (R) 4f states electrons, which are responsible for the ground state ferromagnetic (FM) behavior of the systems. The FM behavior of these systems is strongly influenced by the average number of Cr-3d and Sm (Gd) 4f-electrons. The effective moment of SmCrSb 3 is found to be 7.07 μ B while for GdCrSb 3 it is 8.27 μ B . The Cr atom plays a significant role on the magnetic properties due to the hybridization between Cr-3d and Sb-5p states. - Highlights: → DOS and the magnetic moments of SmCrSb 3 and GdCrSb 3 are studied by full-FP-LAPW method. → Exchange splitting of eg and t2g of Cr-3d states and the rare-earth 4f state electrons are responsible for ground state ferromagnetism. → Rare-earth magnetic moments are greater than Cr moment indicating presence of 4f states.

HFO operation with CR injection

Energy Technology Data Exchange (ETDEWEB)

Poensgen, Christian [MAN-Diesel und Turbo SE, Augsburg (Germany)

2011-07-01

In 1996 MAN Diesel and Turbo SE started the development of a CR-system for medium speed engines for HFO operation up to fuel viscosity of 700 cSt. 2004 the first field test engine, a 7L 32/40 GenSet was put into service as a retrofit and collected up to now more than 20.000 running hours operated on HFO on a large container vessel. Meanwhile several L32/40 CR GenSets, L32/44 CR, V48/60 CR and L21/31 CR engines collected more than 100000 running hours in HFO operation before MAN Diesel started up the serial production of the new 32/44 CR and 48/60 CR engines. All of these engines are still in service. The paper will give an overview about the field experience and countermeasures which were necessary to develop a reliable product which fulfills the customers' demands concerning low fuel oil consumption, invisible smoke over the whole load range, low emission levels and maintenance costs. The experience was made in a wide range of applications such as GenSet, Cruise Vessel main propulsion and ferry main propulsion running 24h/day. The field test engines reached an availability of more than 90% per year. The paper also will point out the win/win situation for the the manufacturer and customer to participate in the development of the CR technology. For customers satisfaction MAN Diesel provides help for easy handling like online access per satellite connection, easy leakage detection and operator training at site or at the new built academies. The flexibility of the CR-system is the base frame for the future development of engines which fulfills IMO TIER II and IMO TIER III with high efficiency. The necessary reliability, a must, has been proven in the field under real conditions. (orig.)

Complex analysis and CR geometry

CERN Document Server

Zampieri, Giuseppe

2008-01-01

Cauchy-Riemann (CR) geometry is the study of manifolds equipped with a system of CR-type equations. Compared to the early days when the purpose of CR geometry was to supply tools for the analysis of the existence and regularity of solutions to the \\bar\\partial-Neumann problem, it has rapidly acquired a life of its own and has became an important topic in differential geometry and the study of non-linear partial differential equations. A full understanding of modern CR geometry requires knowledge of various topics such as real/complex differential and symplectic geometry, foliation theory, the geometric theory of PDE's, and microlocal analysis. Nowadays, the subject of CR geometry is very rich in results, and the amount of material required to reach competence is daunting to graduate students who wish to learn it. However, the present book does not aim at introducing all the topics of current interest in CR geometry. Instead, an attempt is made to be friendly to the novice by moving, in a fairly relaxed way, f...

Biosorption of Cr(VI) by coconut coir: Spectroscopic investigation on the reaction mechanism of Cr(VI) with lignocellulosic material

International Nuclear Information System (INIS)

Shen, Ying-Shuian; Wang, Shan-Li; Huang, Shiuh-Tsuen; Tzou, Yu-Min; Huang, Jang-Hung

2010-01-01

In this study, the removal mechanism of Cr(VI) from water by coconut coir (CC) was investigated using X-ray photoelectron spectroscopy (XPS), Cr K-edge X-ray absorption near edge structure (XANES) and FTIR spectroscopy. The results showed that, upon reaction with CC at pH 3, Cr(VI) was reduced to Cr(III), which was either bound to CC or released back into solution. As revealed by the FTIR spectra of CC before and after reacting with Cr(VI), the phenolic methoxyl and hydroxyl groups of lignin in CC are the dominant drivers of Cr(VI) reduction, giving rise to carbonyl and carboxyl groups on CC. These functional groups can subsequently provide binding sites for Cr(III) resulting from Cr(VI) reduction. In conjunction with forming complexes with carbonyl and carboxyl groups, the formation of Cr(III) hydroxide precipitate could also readily occur as revealed by the linear combination fitting of the Cr K-edge XANES spectrum using a set of reference compounds. The phenolic groups in lignin are responsible for initiating Cr(VI) reduction, so lignocellulosic materials containing a higher amount of phenolic groups are expected to be more effective scavengers for removal of Cr(VI) from the environment.

Biosorption of Cr(VI) by coconut coir: Spectroscopic investigation on the reaction mechanism of Cr(VI) with lignocellulosic material

Energy Technology Data Exchange (ETDEWEB)

Shen, Ying-Shuian [Department of Soil and Environmental Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Wang, Shan-Li, E-mail: slwang@nchu.edu.tw [Department of Soil and Environmental Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Huang, Shiuh-Tsuen [Department of Soil and Environmental Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Department of Science Application and Dissemination, National Taichung University, Taichung, Taiwan (China); Tzou, Yu-Min; Huang, Jang-Hung [Department of Soil and Environmental Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China)

2010-07-15

In this study, the removal mechanism of Cr(VI) from water by coconut coir (CC) was investigated using X-ray photoelectron spectroscopy (XPS), Cr K-edge X-ray absorption near edge structure (XANES) and FTIR spectroscopy. The results showed that, upon reaction with CC at pH 3, Cr(VI) was reduced to Cr(III), which was either bound to CC or released back into solution. As revealed by the FTIR spectra of CC before and after reacting with Cr(VI), the phenolic methoxyl and hydroxyl groups of lignin in CC are the dominant drivers of Cr(VI) reduction, giving rise to carbonyl and carboxyl groups on CC. These functional groups can subsequently provide binding sites for Cr(III) resulting from Cr(VI) reduction. In conjunction with forming complexes with carbonyl and carboxyl groups, the formation of Cr(III) hydroxide precipitate could also readily occur as revealed by the linear combination fitting of the Cr K-edge XANES spectrum using a set of reference compounds. The phenolic groups in lignin are responsible for initiating Cr(VI) reduction, so lignocellulosic materials containing a higher amount of phenolic groups are expected to be more effective scavengers for removal of Cr(VI) from the environment.

Biosorption of Cr(VI) by coconut coir: spectroscopic investigation on the reaction mechanism of Cr(VI) with lignocellulosic material.

Science.gov (United States)

Shen, Ying-Shuian; Wang, Shan-Li; Huang, Shiuh-Tsuen; Tzou, Yu-Min; Huang, Jang-Hung

2010-07-15

In this study, the removal mechanism of Cr(VI) from water by coconut coir (CC) was investigated using X-ray photoelectron spectroscopy (XPS), Cr K-edge X-ray absorption near edge structure (XANES) and FTIR spectroscopy. The results showed that, upon reaction with CC at pH 3, Cr(VI) was reduced to Cr(III), which was either bound to CC or released back into solution. As revealed by the FTIR spectra of CC before and after reacting with Cr(VI), the phenolic methoxyl and hydroxyl groups of lignin in CC are the dominant drivers of Cr(VI) reduction, giving rise to carbonyl and carboxyl groups on CC. These functional groups can subsequently provide binding sites for Cr(III) resulting from Cr(VI) reduction. In conjunction with forming complexes with carbonyl and carboxyl groups, the formation of Cr(III) hydroxide precipitate could also readily occur as revealed by the linear combination fitting of the Cr K-edge XANES spectrum using a set of reference compounds. The phenolic groups in lignin are responsible for initiating Cr(VI) reduction, so lignocellulosic materials containing a higher amount of phenolic groups are expected to be more effective scavengers for removal of Cr(VI) from the environment. 2010 Elsevier B.V. All rights reserved.

Electrochemical Behavior and Hydrophobic Properties of CrN and CrNiN Coatings in Simulated Proton Exchange Membrane Fuel Cell Environment

Directory of Open Access Journals (Sweden)

JIN Jie

2016-10-01

Full Text Available The CrN and CrNiN coatings were prepared on the surface of 304 stainless steel by closed field unbalanced magnetron sputtering.X ray diffraction and field emission scanning electron microscopy were used to characterize the structure and morphology of the coatings.The electrochemical corrosion properties under the simulated proton exchange membrane fuel cell(PEMFC environment, interfacial contact resistance and hydrophobic properties of the two kinds of different coatings were investigated by electrochemical methods,contact resistance test and hydrophobic test,respectively.The results indicate that CrN coating mainly consists of CrN and Cr2N phase,CrN and Cr2N phases in the CrNiN coating are less compared to CrN film, and Ni exist as element in CrNiN coating; dynamic polarization tests show the coating is of better corrosion resistance,whereas the corrosion resistance of CrNiN coating is worse than that of CrN coating,constant potential polarization test shows the corrosion current density of CrN and CrNiN coatings are equivalent; CrN and CrNiN coatings significantly reduce the interfacial contact resistance of the 304 stainless steel,among which CrN coating has the smallest contact resistance; and CrNiN coating which has better hydrophobicity than that of CrN coating is more beneficial for the water management in proton exchange membrane fuel cell.

A conformation-selective IR-UV study of the dipeptides Ac-Phe-Ser-NH2 and Ac-Phe-Cys-NH2: probing the SH···O and OH···O hydrogen bond interactions.

Science.gov (United States)

Yan, Bin; Jaeqx, Sander; van der Zande, Wim J; Rijs, Anouk M

2014-06-14

The conformational preferences of peptides are mainly controlled by the stabilizing effect of intramolecular interactions. In peptides with polar side chains, not only the backbone but also the side chain interactions determine the resulting conformations. In this paper, the conformational preferences of the capped dipeptides Ac-Phe-Ser-NH2 (FS) and Ac-Phe-Cys-NH2 (FC) are resolved under laser-desorbed jet cooling conditions using IR-UV ion dip spectroscopy and density functional theory (DFT) quantum chemistry calculations. As serine (Ser) and cysteine (Cys) only differ in an OH (Ser) or SH (Cys) moiety; this subtle alteration allows us to study the effect of the difference in hydrogen bonding for an OH and SH group in detail, and its effect on the secondary structure. IR absorption spectra are recorded in the NH stretching region (3200-3600 cm(-1)). In combination with quantum chemical calculations the spectra provide a direct view of intramolecular interactions. Here, we show that both FS as FC share a singly γ-folded backbone conformation as the most stable conformer. The hydrogen bond strength of OH···O (FS) is stronger than that of SH···O (FC), resulting in a more compact gamma turn structure. A second conformer is found for FC, showing a β turn interaction.

Wear resistance of nano- and micro-crystalline diamond coatings onto WC-Co with Cr/CrN interlayers

Energy Technology Data Exchange (ETDEWEB)

Polini, Riccardo [Dipartimento di Scienze e Tecnologie Chimiche, Universita di Roma Tor Vergata, Via della Ricerca Scientifica, 1, Rome, 00133 (Italy); Barletta, Massimiliano, E-mail: barletta@ing.uniroma2.i [Dipartimento di Ingegneria Meccanica, Universita di Roma Tor Vergata, Via del Politecnico, 1, Rome, 00133 (Italy); Cristofanilli, Giacomo [Dipartimento di Scienze e Tecnologie Chimiche, Universita di Roma Tor Vergata, Via della Ricerca Scientifica, 1, Rome, 00133 (Italy)

2010-12-30

Cr/CrN bi-layers have been used recently to promote the growth of high quality Hot Filament Chemical Vapour Deposition (HFCVD) diamond coatings onto Co-cemented tungsten carbide (WC-6 wt.%Co) substrates. In the present investigation, the influence of the crystalline size of the diamond coatings on their wear endurance is looked into. Nano- (NDC) and micro-crystalline Diamond Coatings (MDC) were deposited by HFCVD onto untreated and Fluidized Bed (FB) treated Cr/CrN interlayers. NDCs, characterized by a cauliflower-like morphology, showed improved wear resistance. However, the superimposition of NDCs onto Cr/CrN interlayers micro-corrugated by FB treatment was found to be the most promising choice, leading to the formation of highly adherent and wear resistant coatings.

Development of Cr{sub 3}C{sub 2}-25(Ni20Cr) nanostructured coatings; Desenvolvimento de revestimentos nanostruturados de Cr{sub 3}C{sub 2}-25(Ni20Cr)

Energy Technology Data Exchange (ETDEWEB)

Cunha, Cecilio Alvares da

2012-07-01

This study is divided in two parts. The first part is about the preparation of nanostructured Cr{sub 3}C{sub 2}-25(Ni20Cr) powders by high energy milling followed by characterization of the milled and the as received powder. Analyses of some of the data obtained were done using a theoretical approach. The second part of this study is about the preparation and characterization of coatings prepared with the nanostructured as well as the as received Cr{sub 3}C{sub 2}-25(Ni20Cr) powders. The high temperature erosion-oxidation (E-O) behavior of the coatings prepared with the two types of powders has been compared based on a technological approach. The average crystallite size of the Cr{sub 3}C{sub 2}-25(Ni20Cr) powder decreased rapidly from 145 nm to 50 nm in the initial stages of milling and thereafter decreased slowly to a steady state value of around 10 nm with further increase in milling time. This steady state corresponds to the beginning of a dynamic recovery process. The maximum lattice strain ({epsilon} = 1,17%) was observed in powders milled for 16 hours, and this powders critical crystallite size was 28 nm. In contrast, the lattice parameter attained a minimum for powders milled for 16 hours. Upon reaching the critical crystallite size, the dislocation density attained a steady state regime and all plastic deformation introduced in the material there after was in the form of events occurring at the grain boundaries, due mainly to grain boundary sliding. The deformation energy stored in the crystal lattice of the Cr{sub 3}C{sub 2}-25(Ni20Cr) powders milled for different times was determined from enthalpy variation measurements. These results indicated that the maximum enthalpy variation ({delta}H = 722 mcal) also occurred for powders milled for 16 hours. In a similar manner, the maximum specific heat variation ({delta}C{sub p} = 0,278 cal/gK) occurred for powders milled for 16 hours. The following mechanical properties of Cr{sub 3}C{sub 2}-25(Ni20Cr) coatings

Impact behavior of 9-Cr and 12-Cr ferritic steels after low-temperature irradiation

International Nuclear Information System (INIS)

Klueh, R.L.; Vitek, J.M.; Corwin, W.R.; Alexander, D.J.

1987-01-01

Miniature Charpy impact specimens of 9Cr-1MoVNb and 12Cr-1MoVW steels and these steels with 1 and 2% Ni were irradiated in the High-Flux Isotope Reactor (HFIR) at 50 0 C to displacement damage levels of up to 9 dpa. Nickel was added to study the effect of transmutation helium. Irradiation caused an increase in the ductile-brittle transition temperature (DBTT). The 9Cr-1MoVNb steels, with and without nickel, showed a larger shift than the 12Cr-1MoVW steels, with and without nickel. The results indicated that helium also increased the DBTT. The same steels were previously irradiated at higher temperatures. From the present and past tests, the effect of irradiation temperature on the DBTT behavior can be evaluated. For the 9Cr-1MoVNb steel, there is a continuous decrease in the magnitude of the DBTT increase up to an irradiation temperature of about 400 0 C, after which the shift drops rapidly to zero at about 450 0 C. The DBTT of the 12Cr-1MoVW steel shows a maximum increase at an irradiation temperature of about 400 0 C and less of an increase at either higher or lower irradiation temperatures

Delineation of Ehlers-Danlos syndrome phenotype due to the c.934C>T, p.(Arg312Cys) mutation in COL1A1: Report on a three-generation family without cardiovascular events, and literature review.

Science.gov (United States)

Colombi, Marina; Dordoni, Chiara; Venturini, Marina; Zanca, Arianna; Calzavara-Pinton, Piergiacomo; Ritelli, Marco

2017-02-01

Classical Ehlers-Danlos syndrome (cEDS) is a rare connective tissue disorder primarily characterized by hyperextensible skin, defective wound healing, abnormal scars, easy bruising, and generalized joint hypermobility; arterial dissections are rarely observed. Mutations in COL5A1 and COL5A2 encoding type V collagen account for more than 90% of the patients so far characterized. In addition, cEDS phenotype was reported in a small number of patients carrying the c.934C>T mutation in COL1A1 that results in an uncommon substitution of a non-glycine residue in one Gly-Xaa-Yaa repeat of the pro-α1(I)-chain p.(Arg312Cys), which leads to disturbed collagen fibrillogenesis due to delayed removal of the type I procollagen N-propeptide. This specific mutation has been associated with propensity to arterial rupture in early adulthood; indeed, in literature the individuals harboring this mutation are also referred to as "(classic) vascular-like" EDS patients. Herein, we describe a three-generation cEDS family with six adults carrying the p.(Arg312Cys) substitution, which show a variable and prevalent cutaneous involvement without any major vascular event. These data, together with those available in literature, suggest that vascular events are not a diagnostic handle to differentiate patients with the p.(Arg312Cys) COL1A1 mutation from those with COL5A1 and COL5A2 defects, and highlight that during the diagnostic process the presence of at least the p.(Arg312Cys) substitution in COL1A1 should be investigated in cEDS patients without type V collagen mutations. Nevertheless, for these patients, as well as for those affected with cEDS, a periodical vascular surveillance should be carried out together with cardiovascular risk factors monitoring. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

PENGAMBILAN LOGAM CR6+ DAN CR TOTAL DARI LIMBAH INDUSTRI ELEKTROPLATING SECARA ELEKTROKOGULASI

Directory of Open Access Journals (Sweden)

Muhammad Nizar Pahlevi

2012-10-01

Full Text Available Electroplating industry is a metal coating industry by way of metal precipitate coatings on metal or plastic which is done so that the electrolytic waste containing heavy metals. Electrocoagulation is a process of merging clumps resulting from the flux of electrical current (DC for the extraction of metal compounds contained in wastewater. In this process of reduction and oxidation reactions occur. Where the metal is reduced and the positive electrode (Al will be oxidized to (Al (OH 3 which serves as a coagulant. The purpose of this research to study methods of electrocoagulation using aluminum electrodes and the influence of the length of time stirring and stirring speed of decision-CR6+ levels and total Cr. This electrocoagulation electroplating wastewater with electricity so that the ions are absorbed by the coagulant in waste binder in the release of the electrode and causes the bond between the metal ions with coagulant. Variation of stirrer speed of 200, 400 and 600 rpm, whereas the long stirring time 25, 50 and 75 minutes. Based on test results, after an analysis showed a significant reduction of the levels of total CR6 + and Cr in the electroplating wastes. CR6+ to obtain a decrease of 95.1% at minute 50 and the stirrer speed of 200 rpm, whereas the total Cr obtained a decrease of 82.69% at minute 75 and a stirrer speed of 600 rpm.

Microbial conversion of Cr (VI) in to Cr (III) in industrial effluent ...

African Journals Online (AJOL)

These bacterial strains also take up and reduce Cr (VI) present in industrial effluents, and their reduction potential was not significantly affected in the presence of different metallic salts. Key Words: Cr (VI) reduction, bacteria, industrial effluent, heavy metals. African Journal of Biotechnology Vol.3(11) 2004: 610-617 ...

A Trp474Cys mutation in the alpha-subunit of beta-hexosaminidase causes a subacute encephalopathic form of G{sub M2} gangliosidosis, type 1

Energy Technology Data Exchange (ETDEWEB)

Petroulakis, E.; Cao, Z.; Salo, T. [Univ. of Manitoba, Winnipeg (Canada)] [and others

1994-09-01

Mutations in the HEXA gene that encodes the {alpha}-subunit of the heterodimeric lysosomal enzyme {beta}-hexosaminidase A, or Hex A ({alpha}{beta}), cause G{sub M2} gangliosidosis, type 1. The infantile form (Tay-Sachs disease) results when there is no residual Hex A activity, while less severe and more variable clinical phenotypes result when residual Hex A activity is present. A non-Jewish male who presented with an acute psychotic episode at age 16 was diagnosed with a subacute encephalopathic form of G{sub M2} gangliosidosis. At age 19, chronic psychosis with intermittent acute exacerbations remains the most disabling symptom in this patient and his affected brother although both exhibit some ataxia and moderately severe dysarthria. We have found a 4 bp insertion (+TATC 1278) associated with infantile Tay-Sachs disease on one allele; no previously identified mutation was found on the second allele. SSCP analysis detected a shift in exon 13 and sequencing revealed a G1422C mutation in the second allele that results in a Trp474Cys substitution. The presence of the mutation was confirmed by the loss of HaeIII and ScrFI sites in exon 13 PCR products from the subjects and their father. The mutation was introduced into the {alpha}-subunit cDNA and Hex S ({alpha}{alpha}) and Hex A ({alpha}{beta}) were transiently expressed in monkey COS-7 cells. The Trp474Cys mutant protein had approximately 5% and 12% of wild-type Hex S and Hex A activity, respectively. Western blot analysis revealed a small amount of residual mature {alpha}-subunit and a normal level of precursor protein. We conclude that the Trp474Cys mutation is the cause of the Hex A deficiency associated with a subacute (juvenile-onset) phenotype in this patient. Like other mutations in exon 13 of HEXA, it appears to affect intracellular processing. Studies of the defect in intracellular processing are in progress.

Mechanisms of Mitochondrial Holocytochrome c Synthase and the Key Roles Played by Cysteines and Histidine of the Heme Attachment Site, Cys-XX-Cys-His*

Science.gov (United States)

Babbitt, Shalon E.; San Francisco, Brian; Mendez, Deanna L.; Lukat-Rodgers, Gudrun S.; Rodgers, Kenton R.; Bretsnyder, Eric C.; Kranz, Robert G.

2014-01-01

Mitochondrial cytochrome c assembly requires the covalent attachment of heme by thioether bonds between heme vinyl groups and a conserved CXXCH motif of cytochrome c/c1. The enzyme holocytochrome c synthase (HCCS) binds heme and apocytochrome c substrate to catalyze this attachment, subsequently releasing holocytochrome c for proper folding to its native structure. We address mechanisms of assembly using a functional Escherichia coli recombinant system expressing human HCCS. Human cytochrome c variants with individual cysteine, histidine, double cysteine, and triple cysteine/histidine substitutions (of CXXCH) were co-purified with HCCS. Single and double mutants form a complex with HCCS but not the triple mutant. Resonance Raman and UV-visible spectroscopy support the proposal that heme puckering induced by both thioether bonds facilitate release of holocytochrome c from the complex. His-19 (of CXXCH) supplies the second axial ligand to heme in the complex, the first axial ligand was previously shown to be from HCCS residue His-154. Substitutions of His-19 in cytochrome c to seven other residues (Gly, Ala, Met, Arg, Lys, Cys, and Tyr) were used with various approaches to establish other roles played by His-19. Three roles for His-19 in HCCS-mediated assembly are suggested: (i) to provide the second axial ligand to the heme iron in preparation for covalent attachment; (ii) to spatially position the two cysteinyl sulfurs adjacent to the two heme vinyl groups for thioether formation; and (iii) to aid in release of the holocytochrome c from the HCCS active site. Only H19M is able to carry out these three roles, albeit at lower efficiencies than the natural His-19. PMID:25170082

Microstructure, mechanical and tribological characterization of CrN/DLC/Cr-DLC multilayer coating with improved adhesive wear resistance

Science.gov (United States)

Sui, Xudong; Liu, Jinyu; Zhang, Shuaituo; Yang, Jun; Hao, Junying

2018-05-01

Adhesive wear is one of the major reasons for the failure of components during various tribological application, especially for rubbing with viscous materials. This study presents CrN/DLC/Cr-DLC multilayer composite coatings prepared on a plasma enhanced chemical vapor deposition (PECVD) device with the close field unbalanced magnetron sputtering ion plating (CFUBMSIP) technique. SEM, XRD and Raman spectroscopy were used to determine the structure of multilayer coatings. It was found that the multilayer coatings are composed by the alternating CrN and DLC layers. Compared with the single CrN coatings, the friction coefficient of the CrN/DLC/Cr-DLC multilayer coating decreases about more than seven times after sliding a distance of 500 m. This helps to reduce the adhesive wear of multilayer coatings. Compared with the single CrN and DLC coating, the wear rate of the CrN/DLC/Cr-DLC multilayer coating is reduced by an order of magnitude to 7.10 × 10-17 (sliding with AISI 440C) and 2.64 × 10-17 (sliding with TC4) m3/(N m). The improved tribological performance of multilayer coatings mainly attributes to the introduction of lubricant DLC and hard support CrN layers, the enhancement of crack propagation inhibition, and the increment of elastic recovery value We (71.49%) by multilayer design method.

Different roles of ROS and Nrf2 in Cr(VI)-induced inflammatory responses in normal and Cr(VI)-transformed cells

Energy Technology Data Exchange (ETDEWEB)

Roy, Ram Vinod; Pratheeshkumar, Poyil; Son, Yong-Ok; Wang, Lei [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Department of Toxicology and Cancer Biology, College of Medicine, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Hitron, John Andrew [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Divya, Sasidharan Padmaja; Zhang, Zhuo [Department of Toxicology and Cancer Biology, College of Medicine, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Shi, Xianglin, E-mail: xshi5@email.uky.edu [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States)

2016-09-15

Hexavalent chromium (Cr(VI)) is classified as a human carcinogen. Cr(VI) has been associated with adenocarcinomas and squamous cell carcinoma of the lung. The present study shows that acute Cr(VI) treatment in human bronchial epithelial cells (BEAS-2B) increased inflammatory responses (TNF-α, COX-2, and NF-кB/p65) and expression of Nrf2. Cr(VI)-induced generation of reactive oxygen species (ROS) are responsible for increased inflammation. Despite the fact that Nrf2 is a master regulator of response to oxidative stress, silencing of Nrf2 in the acute Cr(VI) treatment had no effect on Cr(VI)-induced inflammation. In contrast, in Cr(VI)-transformed (CrT) cells, Nrf2 is constitutively activated. Knock-down of this protein resulted in decreased inflammation, while silencing of SOD2 and CAT had no effect in the expression of these inflammatory proteins. Results obtained from the knock-down of Nrf2 in CrT cells are very different from the results obtained in the acute Cr(VI) treatment. In BEAS-2B cells, knock-down of Nrf2 had no effect in the inflammation levels, while in CrT cells a decrease in the expression of inflammation markers was observed. These results indicate that before transformation, ROS plays a critical role while Nrf2 not in Cr(VI)-induced inflammation, whereas after transformation (CrT cells), Nrf2 is constitutively activated and this protein maintains inflammation while ROS not. Constitutively high levels of Nrf2 in CrT binds to the promoter regions of COX-2 and TNF-α, leading to increased inflammation. Collectively, our results demonstrate that before cell transformation ROS are important in Cr(VI)-induced inflammation and after transformation a constitutively high level of Nrf2 is important. - Highlights: • Cr(VI)-induced ROS increased inflammation, while Nrf2 had no effect. • In the CrT cells knock-down of Nrf2 resulted in decreased inflammation. • Mechanistic differences in regulating Cr(VI)-induced inflammation.

Early serum creatinine changes and outcomes in patients admitted for acute heart failure: the cardio-renal syndrome revisited.

Science.gov (United States)

Núñez, Julio; Garcia, Sergio; Núñez, Eduardo; Bonanad, Clara; Bodí, Vicent; Miñana, Gema; Santas, Enrique; Escribano, David; Bayes-Genis, Antonio; Pascual-Figal, Domingo; Chorro, Francisco J; Sanchis, Juan

2017-08-01

The changes in renal function that occurred in patients with acute decompensated heart failure (ADHF) are prevalent, and have multifactorial etiology and dissimilar prognosis. To what extent the prognostic role of such changes may vary according to the presence of renal insufficiency at admission is not clear. Accordingly, we sought to determine whether early creatinine changes (ΔCr) (admission to 48-72 hours) had an effect on 1-year mortality relative to the presence of renal insufficiency at admission. We included 705 consecutive patients admitted with the diagnosis of ADHF. Admission renal insufficiency was defined as serum creatinine ≥1.4mg/dl (A-RI cr ) or estimated glomerular filtration rate renal insufficiency (24.7% and 42.8% for A-RIcr and A-RIGFR, respectively) had higher prevalence of extreme values in ΔCr in either direction (increasing/decreasing). At 1-year follow-up, 114 (16.2%) deaths were registered. The multivariable analysis showed a significant interaction between admission renal insufficiency and ΔCr ( p=0.004 and p=0.019 for A-RIcr and A-RIGFR, respectively). In the presence of renal insufficiency, the continuum of ΔCr followed a positive and almost linear relationship with mortality risk. Conversely, in patients without renal insufficiency, those changes adopted a 'J-shape' trajectory with increased mortality at both ends of the curve distribution. In patients with ADHF the effect of ΔCr on 1-year mortality varied according to its magnitude and the presence of admission renal insufficiency. There was a graded-association with mortality when renal insufficiency was present on admission.

Effects of creatine supplementation along with resistance training on urinary formaldehyde and serum enzymes in wrestlers.

Science.gov (United States)

Nasseri, Azadeh; Jafari, Afshar

2016-04-01

Formaldehyde is a cytotoxic agent produced from creatine through a metabolic pathway, and in this regard, it has been claimed that creatine supplementation could be cytotoxic. Even though the cytotoxic effects of creatine supplementation have been widely studied, yet little is known about how resistance training can alter these toxic effects. This study aimed to determine the effects of short-term creatine supplementation plus resistance training on the level of urinary formaldehyde and concentrations of serum enzymes in young male wrestlers. In a double-blind design twenty-one subjects were randomized into creatine supplementation (Cr), creatine supplementation plus resistance training (Cr + T) and placebo plus resistance training (Pl + T) groups. Participants ingested creatine (0.3 g/kg/day) or placebo for 7 days. The training protocol consisted of 3 sessions in one week, each session including three sets of 6-9 repetitions at 80-85% of one-repetition maximum for whole-body exercise. Urine and blood samples were collected at baseline and at the end of the supplementation. Creatine supplementation significantly increased the excretion rate of urinary formaldehyde in the Cr and Cr + T groups by 63.4% and 30.4%, respectively (P0.05). These findings indicate that resistance training may lower the increase of urinary formaldehyde excretion induced by creatine supplementation, suggesting that creatine consumption could be relatively less toxic when combined with resistance training.

Effect of genotype, Cr(III and Cr(VI on plant growth and micronutrient status in Silene vulgaris (Moench

Directory of Open Access Journals (Sweden)

A. E. Pradas-del-Real

2013-06-01

Full Text Available Chromium released into the environment from industrial activities has become an important environmental concern. Silene vulgaris has been proven to be tolerant to many heavy metals, so it is considered an interesting species in the revegetation and restoration of polluted soils, but no information is available about its response to Cr. The objective of this work was to study uptake and influence on plant growth of Cr(III and Cr(VI in six genotypes (four hermaphrodites and two females of S. vulgaris from different sites of Madrid (Spain. Plants were treated for 12 days with 60 µM of Cr(III or Cr(VI in semihydroponics. Dry weights, soil-plant analysis development values (SPAD reading with chlorophylls and micronutrient and total Cr concentrations were determined. Metal uptake was higher in presence of Cr(VI than of Cr(III and poorly translocated to the shoots. In both cases S. vulgaris did not show visual toxicity symptoms, biomass reduction, or differences among SPAD values as consequence of Cr additions. However genotypes SV36 and SV38 showed Fe and Mn imbalance. This is the first report on the relatively good performance of hermaphrodite and female S. vulgaris genotypes in Cr uptake and physiological traits, but further studies will be necessary to elucidate the mechanisms by which the gender may influence these variables. S. vulgaris presented high diversity at genotypic level; the treatment with hexavalent Cr increased the differences among genotypes so the use of cuttings from an homogeneous genotype seems to be an adequate method for the study of this species.

A novel germ-line point mutation in RET exon 8 (Gly(533)Cys) in a large kindred with familial medullary thyroid carcinoma

OpenAIRE

Silva, Adriana Madeira Alvares da [UNIFESP; Maciel, Rui Monteiro de Barros [UNIFESP; Dias-da-Silva, Magnus Régios [UNIFESP; Toledo, Silvia Regina Caminada de [UNIFESP; De Carvalho, Marcos B.; Cerutti, Janete Maria [UNIFESP

2003-01-01

Familial medullary thyroid carcinoma is related to germ-line mutations in the RET oncogene, mainly in cysteine codon 10 or 11, whereas noncysteine mutations in codons 13 - 15 are rare. We now report a new missense point mutation in exon 8 of the RET gene (1597G-->T) corresponding to a Gly(533)Cys substitution in the cystein-rich domain of RET protein in 76 patients from a 6-generation Brazilian family with 229 subjects, with ascendants from Spain. It is likely that the mutation causes familia...

Solutes transport characteristics in peritoneal dialysis: variations in glucose and insulin serum levels.

Science.gov (United States)

da Silva, Dirceu R; Figueiredo, Ana E; Antonello, Ivan C; Poli de Figueiredo, Carlos E; d'Avila, Domingos O

2008-01-01

Differences in small solutes transport rate (SSTR) during peritoneal dialysis (PD) may affect water and solutes removal. Patients with high SSTR must rely on shorter dwell times and increased dialysate glucose concentrations to keep fluid balance. Glucose absorption during peritoneal dialysis (PD), besides affecting glucose and insulin metabolism, may induce weight gain. The study aimed at examining acute glucose and insulin serum level changes and other potential relationships in PD patients with diverse SSTR. This cross-sectional study used a modified peritoneal equilibration test (PET) that enrolled 34 prevalent PD patients. Zero, 15, 30, 60, 120, 180, and 240-minute glucose and insulin serum levels were measured. Insulin resistance index was assessed by the homeostasis model assessment (HOMA-IR) formula. SSTR categories were classified by quartiles of the four-hour dialysate/serum creatinine ratio (D(4)/P(Cr)). Demographic and clinical variables were evaluated, and the body mass index (BMI) was estimated. Correlations among variables of interest and categories of SSTR were explored. Glucose serum levels were significantly different at 15, 30, and 60 minutes between high and low SSTR categories (p = 0.014, 0.009, and 0.022). Increased BMI (25.5 +/- 5.1) and insulin resistance [HOMA-IR = 2.60 (1.40-4.23)] were evidenced overall. Very strong to moderate correlations between insulin levels along the PET and HOMA-IR (r = 0.973, 0.834, 0.766, 0.728, 0.843, 0.857, 0.882) and BMI (r = 0.562, 0.459, 0.417, 0.370, 0.508, 0.514, 0.483) were disclosed. CONCLUSIONS; Early glucose serum levels were associated with SSTR during a PET. Overweight or obesity and insulin resistance were prevalent. An association between insulin serum levels and BMI was demonstrated.

Observations of a Cast Cu-Cr-Zr Alloy

Science.gov (United States)

Ellis, David L.

2006-01-01

Prior work has demonstrated that Cu-Cr-Nb alloys have considerable advantages over the copper alloys currently used in regeneratively cooled rocket engine liners. Observations indicated that Zr and Nb have similar chemical properties and form very similar compounds. Glazov and Zakharov et al. reported the presence of Cr2Zr in Cu-Cr-Zr alloys with up to 3.5 wt% Cr and Zr though Zeng et al. calculated that Cr2Zr could not exist in a ternary Cu-Cr-Zr alloy. A cast Cu-6.15 wt% Cr-5.25 wt% Zr alloy was examined to determine if the microstructure developed would be similar to GRCop-84 (Cu-6.65 wt% Cr-5.85 wt% Nb). It was observed that the Cu-Cr-Zr system did not form any Cr2Zr even after a thermal exposure at 875 C for 176.5 h. Instead the alloy consisted of three phases: Cu, Cu5Zr, and Cr.

Corrosive and cytotoxic properties of compact specimens and microparticles of Ni-Cr dental alloy.

Science.gov (United States)

Ristic, Ljubisa; Vucevic, Dragana; Radovic, Ljubica; Djordjevic, Snezana; Nikacevic, Milutin; Colic, Miodrag

2014-04-01

Nickel-chromium (Ni-Cr) dental alloys have been widely used in prosthodontic practice, but there is a permanent concern about their biocompatibility due to the release of metal ions. This is especially important when Ni-Cr metal microparticles are incorporated into gingival tissue during prosthodontic procedures. Therefore, the aim of this study was to examine and compare the corrosion and cytotoxic properties of compact specimens and microparticles of Ni-Cr dental alloy. Ni-Cr alloy, Remanium CSe bars (4 mm diameter), were made by the standard casting method and then cut into 0.5-mm-thick disks. Metal particles were obtained by scraping the bars using a diamond instrument for crown preparation. The microstructure was observed by an optical microscope. Quantitative determination and morphological and dimensional characterization of metal particles were carried out by a scanning electron microscope and Leica Application Suite software for image analysis. Corrosion was studied by conditioning the alloy specimens in the RPMI 1640 medium, containing 10% fetal calf serum in an incubator with 5% CO2 for 72 hours at 37°C. Inductively coupled plasma-optical emission spectrometry was used to assess metal ion release. The cytotoxity of conditioning medium (CM) was investigated on L929 cells using an MTT test. One-way ANOVA was used for statistical analysis. After casting, the microstructure of the Remanium CSe compact specimen composed of Ni, Cr, Mo, Si, Fe, Al, and Co had a typical dendritic structure. Alloy microparticles had an irregular shape with a wide size range: from less than 1 μm to more than 100 μm. The release of metal ions, especially Ni and Mo from microparticles, was significantly higher, compared to the compact alloy specimen. The CM prepared from compact alloy was not cytotoxic at any tested dilutions, whereas CM from alloy microparticles showed dose-dependent cytotoxicity (90% CM and 45% CM versus control; p alloy. This could affect health on long

Effect of chromium chloride supplementation on glucose tolerance and serum lipids including high-density lipoprotein of adult men.

Science.gov (United States)

Riales, R; Albrink, M J

1981-12-01

Chromium deficiency may cause insulin resistance, hyperinsulinemia, impaired glucose tolerance, and hyperlipidemia, recovered by chromium supplementation. The effect of chromium supplementation on serum lipids and glucose tolerance was tested in a double-blind 12-wk study of 23 healthy adult men aged 31 to 60 yr. Either 200 micrograms trivalent chromium in 5 ml water (Cr) or 5 ml plain water (W) was ingested daily 5 days each week. Half the subjects volunteered for glucose tolerance tests with insulin levels. At 12 wk high-density lipoprotein cholesterol increased in the Cr group from 35 to 39 mg/dl (p less than 0.05) but did not change in the water group (34 mg/dl). The largest increase in high-density lipoprotein cholesterol and decreases in insulin and glucose were found in those subjects having normal glucose levels together with elevated insulin levels at base-line. The data are thus consistent with the hypothesis that Cr supplementation raises high-density lipoprotein cholesterol and improves insulin sensitivity in those with evidence of insulin resistance but normal glucose tolerance.

Millimeter-wave spectroscopy of CrC (X(3)Σ(-)) and CrCCH (X̃ (6)Σ(+)): Examining the chromium-carbon bond.

Science.gov (United States)

Min, J; Ziurys, L M

2016-05-14

Pure rotational spectroscopy of the CrC (X(3)Σ(-)) and CrCCH (X̃ (6)Σ(+)) radicals has been conducted using millimeter/sub-millimeter direct absorption methods in the frequency range 225-585 GHz. These species were created in an AC discharge of Cr(CO)6 and either methane or acetylene, diluted in argon. Spectra of the CrCCD were also recorded for the first time using deuterated acetylene as the carbon precursor. Seven rotational transitions of CrC were measured, each consisting of three widely spaced, fine structure components, arising from spin-spin and spin-rotation interactions. Eleven rotational transitions were recorded for CrCCH and five for CrCCD; each transition in these cases was composed of a distinct fine structure sextet. These measurements confirm the respective (3)Σ(-) and (6)Σ(+) ground electronic states of these radicals, as indicated from optical studies. The data were analyzed using a Hund's case (b) Hamiltonian, and rotational, spin-spin, and spin-rotation constants have been accurately determined for all three species. The spectroscopic parameters for CrC were significantly revised from previous optical work, while those for CrCCH are in excellent agreement; completely new constants were established for CrCCD. The chromium-carbon bond length for CrC was calculated to be 1.631 Å, while that in CrCCH was found to be rCr-C = 1.993 Å - significantly longer. This result suggests that a single Cr-C bond is present in CrCCH, preserving the acetylenic structure of the ligand, while a triple bond exists in CrC. Analysis of the spin constants suggests that CrC has a nearby excited (1)Σ(+) state lying ∼16 900 cm(-1) higher in energy, and CrCCH has a (6)Π excited state with E ∼ 4800 cm(-1).

Morphology, deformation, and defect structures of TiCr2 in Ti-Cr alloys

International Nuclear Information System (INIS)

Chen, K.C.; Allen, S.M.; Livingston, J.D.

1992-01-01

The morphologies and defect structures of TiCr 2 in several Ti-Cr alloys have been examined by optical metallography, x-ray diffraction, and transmission electron microscopy (TEM), in order to explore the room-temperature deformability of the Laves phase TiCr 2 . The morphology of the Laves phase was found to be dependent upon alloy composition and annealing temperature. Samples deformed by compression have also been studied using TEM. Comparisons of microstructures before and after deformation suggest an increase in twin, stacking fault, and dislocation density within the Laves phase, indicating some but not extensive room-temperature deformability

Comparison of Calorie-Restricted Diet and Resveratrol Supplementation on Anthropometric Indices, Metabolic Parameters, and Serum Sirtuin-1 Levels in Patients With Nonalcoholic Fatty Liver Disease: A Randomized Controlled Clinical Trial.

Science.gov (United States)

Asghari, Somayyeh; Asghari-Jafarabadi, Mohammad; Somi, Mohammad-Hossein; Ghavami, Seyed-Mostafa; Rafraf, Maryam

2018-01-01

There is a promising perspective regarding the potential effect of resveratrol in preventing and treating metabolic disturbances similar to that of calorie restriction. The aim of this study was to evaluate the effects of calorie-restricted (CR) diet on metabolic parameters and then to investigate whether resveratrol supplementation has beneficial effects similar to CR diet in patients with nonalcoholic fatty liver disease (NAFLD). This randomized controlled clinical trial was conducted in 90 patients with NAFLD (males and females) aged 20 to 60 years with body mass index (BMI) ranging from 25 to 35 kg/m 2 . Participants were assigned to one of three intervention groups as follows: The CR diet group (n = 30) received a prescribed low-calorie diet, the resveratrol group (n = 30) received 600 mg pure trans-resveratrol (2 × 300 mg) daily, and the placebo group (n = 30) received placebo capsules (2 × 300 mg) daily for 12 weeks. Fasting blood samples, anthropometric measurements, and dietary intake and physical activity data were collected for all participants at baseline and at the end of the trial. CR diet significantly reduced weight (by 4.5%); BMI; waist circumference; waist-to-hip ratio; and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lipid profiles in participants compared to resveratrol and placebo (all p 0.05). No significant changes were seen in hepatic steatosis grade, serum glycemic parameters, and high-density lipoprotein cholesterol and sirtuin-1 levels in any group (all p > 0.05). CR diet with moderate weight loss has favorable effects on NAFLD, and resveratrol supplementation induced weight loss but failed to mimic other aspects of CR diet. Future studies are warranted to evaluate the long-term and dose-dependent effects of resveratrol on metabolic diseases.

Development of improved HP/IP rotor material 2% CrMoNiWV (23 CrMoNiWV 88)

International Nuclear Information System (INIS)

Wiemann, W.

1989-01-01

The new 2% CrMoNiWV steel has a sufficient strength level, a very good creep (rupture) behaviour and an excellent toughness behaviour for a creep resistant steel. Even after long time high temperature exposure the toughness degradation is so small that it is still better than this of best 1% CrMo(Ni)V steels. The fatigue behaviour is well comparable to this of 1% CrMo(Ni)V. The 2% CrMoNiWV steel has the capability to substitute the traditional 1% CrMo(Ni)V. (orig.) With 26 annexes

Corrosion resistance of amorphous NiCrZr and NiCrMoZr alloys

International Nuclear Information System (INIS)

Naka, M.; Miyake, M.; Okamoto, I.

1987-01-01

One of the authors has reported that the corrosion resistance of chromium containing amorphous alloys is extremely improved by alloying phosphorus among metalloids. Two factors operate for the improvement of corrosion resistance of the amorphous alloys. First, phosphorus serves for the rapid formation of protective passive film. Second, the compositional and structural homogeneity in amorphous state also account for the formation of protective film. The latter factor has been clearly seen in the high corrosion resistance of CoCrMoZr and CoCrWZr alloys without metalloids. In order to clarify the separately two factors in the corrosion resistance of amorphous alloys, the corrosion resistance of amorphous alloys without metalloids has to be further investigated. This paper also deals with the corrosion resistance and electrochemical behavior of NiCrZr and NiCrMoZr alloys in 1N HCl, and compare them with the corrosion behavior of the crystalline alloys containing the same composition as that of the amorphous alloys

The irradiation hardening of Ni-Mo-Cr and Ni-W-Cr alloy under Xe26+ ion irradiation

Science.gov (United States)

Chen, Huaican; Hai, Yang; Liu, Renduo; Jiang, Li; Ye, Xiang-xi; Li, Jianjian; Xue, Wandong; Wang, Wanxia; Tang, Ming; Yan, Long; Yin, Wen; Zhou, Xingtai

2018-04-01

The irradiation hardening of Ni-Mo-Cr and Ni-W-Cr alloy was investigated. 7 MeV Xe26+ ion irradiation was performed at room temperature and 650 °C with peak damage dose from 0.05 to 10 dpa. With the increase of damage dose, the hardness of Ni-Mo-Cr and Ni-W-Cr alloy increases, and reaches saturation at damage dose ≥1 dpa. Moreover, the damage dose dependence of hardness in both alloys can be described by the Makin and Minter's equation, where the effective critical volume of obstacles can be used to represent irradiation hardening resistance of the alloys. Our results also show that Ni-W-Cr alloy has better irradiation hardening resistance than Ni-Mo-Cr alloy. This is ascribed to the fact that the W, instead of Mo in the alloy, can suppress the formation of defects under ion irradiation.

Oxidation-resistant Ge-doped silicide coating on Cr-Cr2Nb alloys by pack cementation

International Nuclear Information System (INIS)

He Yirong

1997-01-01

The halide-activated pack cementation process was modified to produce a Ge-doped silicide diffusion coating on Cr-Cr 2 Nb alloys in a single processing step. The morphology and composition of the coating depended both on the pack composition and processing schedule and also on the composition and microstructure of the substrate. Higher Ge content in the pack suppressed the formation of CrSi 2 and reduced the growth kinetics of the coating. Ge was not homogeneously distributed in the coatings. Under cyclic and isothermal oxidation conditions, the Ge-doped silicide coating protected the Cr-Nb alloys from significant oxidation and from pesting by the formation of a Ge-doped silica film. (orig.)

Substrate bias effects on composition and coercivity of CoCrTa/Cr thin films on canasite and glass

Science.gov (United States)

Deng, Y.; Lambeth, D. N.; Sui, X.; Lee, L.-L.; Laughlin, D. E.

1993-05-01

CoCrTa/Cr thin films were prepared by rf diode sputtering onto canasite and glass substrates at various bias voltages from two targets of different compositions (Co82.8Cr14.6Ta2.6 and Co86Cr12Ta2). While Auger depth profile analysis indicates that there is some broadening at the CoCrTa-Cr interface, x-ray fluorescence spectroscopy reveals that changes in alloy composition due to the resputtering processes are even more prominent. For both targets, as the substrate bias increases the Co content in the films declines, and the magnetization decreases. The maximum film coercivity appears to correlate to the final film composition. By investigating the results from both targets, it is concluded that the coercivity reaches a maximum when the film composition is in the neighborhood of Co84Cr13Ta3. Thus, to optimize the coercivity different bias voltages are required for each target. Excessive substrate bias, however, leads to films with low magnetization and coercivity.

Ductilization of Cr via oxide dispersions

International Nuclear Information System (INIS)

Brady, M.P.; Wright, I.G.; Anderson, I.M.; Sikka, V.K.; Ohriner, E.K.; Walls, C.; Westmoreland, G.; Weaver, M.L.

2001-01-01

Work by Scruggs et al. in the 1960's demonstrated that up to 20 % tensile ductility could be achieved at room-temperature in sintered and extruded powder metallurgical Cr alloyed with MgO. During sintering, much of the MgO converts to a MgCr 2 O 4 spinel, which was hypothesized to getter nitrogen from the Cr, rendering it ductile. Recent efforts at Oak Ridge National Laboratory (ORNL) have succeeded in duplicating this original effect. Preliminary results suggest that the ductilization mechanism may be more complicated than the simple nitrogen gettering mechanism proposed by Scruggs, as some ductility was observed at room-temperature in Cr-MgO alloys containing nitride precipitates. Results of microstructural characterization and room-temperature mechanical property studies are presented for Cr-6MgO-(0-2.2) Ti wt.% as a function of hot-pressing and extrusion. Possible mechanisms by which the MgO additions may improve the room-temperature ductility of Cr are discussed. (author)

Tantalum-containing Z-phase in 12%Cr martensitic steels

DEFF Research Database (Denmark)

Danielsen, Hilmar Kjartansson; Hald, John

2009-01-01

Z-phases in tantalum-containing 12%Cr steels have been investigated. In 12%Cr steel without any Nb or V, the formation of CrTaN Z-phases was observed. In 12%Cr steel which also contained V, the Ta entered Z-phase as a minor element, Cr(V,Ta)N. The crystal structure of Cr(V,Ta)N seems to be identi......Z-phases in tantalum-containing 12%Cr steels have been investigated. In 12%Cr steel without any Nb or V, the formation of CrTaN Z-phases was observed. In 12%Cr steel which also contained V, the Ta entered Z-phase as a minor element, Cr(V,Ta)N. The crystal structure of Cr(V,Ta)N seems...

Characterization of Cr-rich Cr-Sb multilayer films: Syntheses of a new metastable phase using modulated elemental reactants

International Nuclear Information System (INIS)

Regus, Matthias; Mankovsky, Sergiy; Polesya, Svitlana; Kuhn, Gerhard; Ditto, Jeffrey; Schürmann, Ulrich; Jacquot, Alexandre; Bartholomé, Kilian; Näther, Christian; Winkler, Markus; König, Jan D.; Böttner, Harald; Kienle, Lorenz; Johnson, David C.; Ebert, Hubert; Bensch, Wolfgang

2015-01-01

The new metastable compound Cr 1+x Sb with x up to 0.6 has been prepared via a thin film approach using modulated elemental reactants and investigated by in-situ X-ray reflectivity, X-ray diffraction, differential scanning calorimetry, energy dispersive X-ray analysis as well as transmission electron microscopy and atomic force microscopy. The new Cr-rich antimonide crystallizes in a structure related to the Ni 2 In-type structure, where the crystallographic position (1/3, 2/3, 3/4) is partially occupied by excess Cr. The elemental layers of the pristine material interdiffused significantly before Cr 1+x Sb crystallized. A change in the activation energy was observed for the diffusion process when crystal growth starts. First-principles electronic structure calculations provide insight into the structural stability, magnetic properties and resistivity of Cr 1+x Sb. - Graphical abstract: 1 amorphous multilayered film 2 interdiffused amorphous film 3 metastable crystalline phase 4 thermodynamic stable phase (and by-product). - Highlights: • Interdiffusion of amorphous Cr and Sb occurs before crystallization. • Crystallization of a new metastable phase Cr 1.6 Sb in Ni 2 In-type structure. • The new Cr-rich phase shows half-metallic behavior

Cu-Cr Literature Review

Energy Technology Data Exchange (ETDEWEB)

Need, Ryan F. [Los Alamos National Laboratory

2012-08-09

Cu-Cr alloys are part of a class of face-centered cubic (FCC)-body-centered cubic (BCC) composites that includes similar alloys, such as Cu-Nb and Cu-Ta. When heavily deformed, these FCC-BCC materials create 'in situ' composites with a characteristic structure-nanoscale BCC filaments in a ductile FCC matrix. The strength of these composites is vastly greater than predicted by the rule of mixtures, and has been shown to be inversely proportional to the filament spacing. Lower raw materials costs suggest that Cu-Cr alloys may offer more economical solution to high-strength, high-conductivity wire than either their Nb or Ta counterparts. However, Cr is also more brittle and soluble in Cu than Nb or Ta. These qualities necessitate thermal treatments to remove solute atoms from the Cu matrix, improve conductivity, and maintain the ductility of the Cr filaments. Through the use of different thermomechanical processing routes or the addition of select dopants, alloys with strength in excess of 1 GPa at 70% IACS have been achieved. To date, previous research on Cu-Cr alloys has focused on a relatively small number of alloy compositions and processing methods while the effects of dopants and ageing treatments have only been studied independently. Consequently, there remains considerable opportunity for the development and optimization of these alloys as a leading high-strength, high-conductivity material.

Thermodynamic Assessment of the La-Cr-O System

DEFF Research Database (Denmark)

Povoden, E.; Chen, Ming; Grundy, A.N.

2009-01-01

of oxygen partial pressure. In the La-Cr system reported solubility of lanthanum in bcc chromium is considered in the modeling. In the La-Cr-O system the Gibbs energy functions of La2CrO6, La-2(CrO4)(3), and perovskite-structured LaCrO3 are presented, and oxygen solubilities in bcc and fcc metals......The La-Cr and the La-Cr-O systems are assessed using the Calphad approach. The calculated La-Cr phase diagram as well as LaO1.5-CrO1.5 phase diagrams in pure oxygen, air, and under reducing conditions are presented. Phase equilibria of the La-Cr-O system are calculated at 1273 K as a function...... are modeled. Emphasis is placed on a detailed description of the perovskite phase: the orthorhombic to rhombohedral transformation and the contribution to the Gibbs energy due to a magnetic order-disorder transition are considered in the model. The following standard data of stoichiometric perovskite...

Effects of lipopolysaccharides on the corrosion behavior of Ni-Cr and Co-Cr alloys.

Science.gov (United States)

Yu, Weiqiang; Qian, Chao; Weng, Weimin; Zhang, Songmei

2016-08-01

Lipopolysaccharides (LPS) are constituents of gingival crevicular fluid and may affect the base metal alloys used in metal ceramic crowns. The role of LPS in base metal alloys is currently unknown. The purpose of this in vitro study was to evaluate the effects of gram-negative bacterial LPS on the electrochemical behavior of Ni-Cr and Co-Cr alloys. Alloy specimens were divided into 4 groups according to Escherichia coli LPS concentration (0, 0.15, 15, and 150 μg/mL) in acidic saliva (pH 5). Open circuit potential (OCP) and potentiodynamic polarization behavior were examined using a computer-controlled potentiostat. Metal ions released from the 2 alloys were measured by immersion in LPS-free solution and 150 μg/mL LPS solution and analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). Data were evaluated using 1-way ANOVA (α=.05). Compared with control groups, medium LPS concentration (15 μg/mL) accelerated Ni-Cr alloy corrosion (Palloy corrosion (Pcorrosion current density, and polarization resistance parameters. After immersion in high LPS concentrations (150 μg/mL), a slight increase in Ni ion release (P >.05) was observed for the Ni-Cr alloy, while a more significant Co ion release (Palloy. LPS negatively affected the electrochemical behavior of both the Ni-Cr and Co-Cr alloys. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Determination of Cr(VI) and Cr(III) in urine and dextrose by inductively coupled plasma emission spectroscopy

Science.gov (United States)

Mianzhi, Zhuang; Barnes, Ramon M.

The determination of Cr(VI) and Cr(III) in human urine and in commercial dextrose solution is performed by induclively coupled plasma-atomic emission spectroscopy after selective preconcentration of the chromium species at different pH values by poly(dithiocarbamate) and poly(acrylamidoxime) chelating resins. The chelating properties of these resins with chromium, including the kinetics of uptake and removal of Cr(III), and the influence of matrix concentrations were evaluated. Chromium in human urine was found to exist exclusively as Cr(III).

Effect of 6-Month Calorie Restriction and Exercise on Serum and Liver Lipids and Markers of Liver Function

Science.gov (United States)

Larson-Meyer, D. Enette; Newcomer, Bradley R.; Heilbronn, Leonie K.; Volaufova, Julia; Smith, Steven R.; Alfonso, Anthony J.; Lefevre, Michael; Rood, Jennifer C.; Williamson, Donald A.; Ravussin, Eric

2009-01-01

objective Nonalcoholic fatty liver disease (NAFLD) and its association with insulin resistance are increasingly recognized as major health burdens. The main objectives of this study were to assess the relation between liver lipid content and serum lipids, markers of liver function and inflammation in healthy overweight subjects, and to determine whether caloric restriction (CR) (which improves insulin resistance) reduces liver lipids in association with these same measures. Methods and Procedures Forty-six white and black overweight men and women (BMI = 24.7-31.3 kg/m2) were randomized to “control (CO)” = 100% energy requirements; “CR” = 25%; “caloric restriction and increased structured exercise (CR+EX)”= 12.5% CR + 12.5% increase in energy expenditure through exercise; or “low-calorie diet (LCD)” = 15% weight loss by liquid diet followed by weight-maintenance, for 6 months. Liver lipid content was assessed by magnetic resonance spectroscopy (MRS) and computed tomography (CT). Lipid concentrations, markers of liver function (alanine aminotransferase (ALT), alkaline phosphatase (ALK)), and whole-body inflammation (tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP)) were measured in fasting blood. Results At baseline, increased liver lipid content (by MRS) correlated (P triglyceride (r = 0.52), ALT (r = 0.42), and hsCRP (r = 0.33) concentrations after adjusting for sex, race, and alcohol consumption. With CR, liver lipid content was significantly lowered by CR, CR+EX, and LCD (detected by MRS only). The reduction in liver lipid content, however, was not significantly correlated with the reduction in triglycerides (r = 0.26; P = 0.11) or with the changes in ALT, high-density lipoprotein (HDL)-cholesterol, or markers of whole-body inflammation. Discussion CR may be beneficial for reducing liver lipid and lowering triglycerides in overweight subjects without known NAFLD. PMID:18421281

Development of low-Cr ODS FeCrAl alloys for accident-tolerant fuel cladding

Science.gov (United States)

Dryepondt, Sebastien; Unocic, Kinga A.; Hoelzer, David T.; Massey, Caleb P.; Pint, Bruce A.

2018-04-01

Low-Cr oxide dispersion strengthened (ODS) FeCrAl alloys were developed as accident tolerant fuel cladding because of their excellent oxidation resistance at very high temperature, high strength and improved radiation tolerance. Fe-12Cr-5Al wt.% gas atomized powder was ball milled with Y2O3+FeO, Y2O3+ZrO2 or Y2O3+TiO2, and the resulting powders were extruded at 950 °C. The resulting fine grain structure, particularly for the Ti and Zr containing alloys, led to very high strength but limited ductility. Comparison with variants of commercial PM2000 (Fe-20Cr-5Al) highlighted the significant impact of the powder consolidation step on the alloy grain size and, therefore, on the alloy mechanical properties at T < 500 °C. These low-Cr compositions exhibited good oxidation resistance at 1400 °C in air and steam for 4 h but could not form a protective alumina scale at 1450 °C, similar to observations for fine grained PM2000 alloys. The effect of alloy grain size, Zr and Ti additions, and impurities on the alloy mechanical and oxidation behaviors are discussed.

Prediction of the Pharmacokinetic Parameters of Triptolide in Rats Based on Endogenous Molecules in Pre-Dose Baseline Serum

Science.gov (United States)

Aa, Jiye; Zheng, Tian; Shi, Jian; Li, Mengjie; Wang, Xinwen; Zhao, Chunyan; Xiao, Wenjing; Yu, Xiaoyi; Sun, Runbin; Gu, Rongrong; Zhou, Jun; Wu, Liang; Hao, Gang; Zhu, Xuanxuan; Wang, Guangji

2012-01-01

Background Individual variances usually affect drug metabolism and disposition, and hence result in either ineffectiveness or toxicity of a drug. In addition to genetic polymorphism, the multiple confounding factors of lifestyles, such as dietary preferences, contribute partially to individual variances. However, the difficulty of quantifying individual diversity greatly challenges the realization of individualized drug therapy. This study aims at quantitative evaluating the association between individual variances and the pharmacokinetics. Methodology/Principal Findings Molecules in pre-dose baseline serum were profiled using gas chromatography mass spectrometry to represent the individual variances of the model rats provided with high fat diets (HFD), routine chows and calorie restricted (CR) chows. Triptolide and its metabolites were determined using high performance liquid chromatography mass spectrometry. Metabonomic and pharmacokinetic data revealed that rats treated with the varied diets had distinctly different metabolic patterns and showed differential Cmax values, AUC and drug metabolism after oral administration of triptolide. Rats with fatty chows had the lowest Cmax and AUC values and the highest percentage of triptolide metabolic transformation, while rats with CR chows had the highest Cmax and AUC values and the least percentage of triptolide transformation. Multivariate linear regression revealed that in baseline serum, the concentrations of creatinine and glutamic acid, which is the precursor of GSH, were linearly negatively correlated to Cmax and AUC values. The glutamic acid and creatinine in baseline serum were suggested as the potential markers to represent individual diversity and as predictors of the disposal and pharmacokinetics of triptolide. Conclusions/Significance These results highlight the robust potential of metabonomics in characterizing individual variances and identifying relevant markers that have the potential to facilitate

THE SYNTHESIS OF Cr2O3-PILLARED MONTMORILLONITE (CrPM AND ITS USAGE FOR HOST MATERIAL OF p-NITROANILINE

Directory of Open Access Journals (Sweden)

Karna Wijaya

2010-06-01

Full Text Available The synthesis of Cr2O3-pillared montmorillonite (CrPM and its usage for host material of p-nitroaniline have been conducted. The Cr2O3-pillared montmorillonite clays was prepared by a direct ion exchange method. First, the polyhydroxychromium as a pillaring spesies was intercalated into the interlayer region of the montmorillonite clays (purified clay in the monocation form, result in a montmorillonite-polyoxychromium intercalation compound. The precursors/pillaring spesies was not stable, hence it must be stabilized by calcination in order to transform the polyoxychromium via dehydration and dehydroxylation processes into Cr2O3. This oxide constituts the so-called pillar that prop the clay layers apart to a relatively large distance. The Cr2O3-pillared clays as a host material was added into ethanol solution saturated with p-nitroaniline, and mixture was stirred for 24 h at room temperature. The Na-montmorillonite, Cr2O3-pillared clay and p-nitroaniline-Cr2O3-pillared clay (pNA-CrPM were characterized by X-Ray Diffraction (XRD, Gas Sorption Analysis, Infrared Spectroscopy (FTIR and Activated Neutron Analysis (ANA methods. The result of research showed that basal spacing (d001 of Cr2O3-pillared montmorillonite (CrPM was 18,55 Å, meanwhile the basal spacing of the hydrated Na-montmorillonite was 14,43 Å. The specific surface area of the Cr2O3-pillared montmorillonite was 174,308 m2/g, whereas p-nitroaniline-Cr2O3-pillared clay (pNA-CrPM was 133,331641 m2/g. This fact indicated that p-nitroaniline has been included into the pore of the Cr2O3-pillared clay.   Keyword: montmorillonite, pillared-clay, ion exchange, intercalate.

Hot Corrosion Behavior of Bare, Cr3C2-(NiCr) and Cr3C2-(NiCr) + 0.2wt.%Zr Coated SuperNi 718 at 900 °C

Science.gov (United States)

Mudgal, Deepa; Singh, Surendra; Prakash, Satya

2015-01-01

Corrosion in incinerators, power plants, and chemical industries are frequently encountered due to the presence of salts containing sodium, sulphur, and chlorine. To obviate this problem, bare and coated alloys were tested under environments simulating the conditions present inside incinerators and power plants. 0.2 wt.% zirconium powder was incorporated in the Cr3C2-(NiCr) coating powder. The original powder and Zr containing powder was sprayed on Superni 718 alloy by D-gun technique. The bare and coated alloys were tested under Na2SO4 + K2SO4 + NaCl + KCl and Na2SO4 + NaCl environment. The corrosion rate of specimens was monitored using weight change measurements. Characterization of the corrosion products has been done using FE-SEM/EDS and XRD techniques. Bare and coated alloys showed very good corrosion resistance under given molten salt environments. Addition of 0.2wt.%Zr in Cr3C2-25%(NiCr) coating further greatly reduced the oxidation rate as well as improved the adherence of oxide scale to the coating surface during the time of corrosion.

Interdiffusion processes at irradiated Cr/Si interfaces

Energy Technology Data Exchange (ETDEWEB)

Luneville, L., E-mail: laurence.luneville@cea.fr [DEN/DANS/DM2S/SERMA/LLPR/LRC-CARMEN, CEA Saclay, 91191 Gif-sur-Yvette (France); Largeau, L. [LPN-UPR20/CNRS, Route de Nozay, 91460 Marcoussis (France); Deranlot, C. [Unite Mixte de Physique CNRS/Thales, 1 Avenue Augustin Fresnel, 91767 Palaiseau (France); Ribis, J. [DEN/DANS/DMN/SRMA/LA2M/LRC-CARMEN, CEA Saclay, 91191 Gif-sur-Yvette (France); Ott, F. [DSM/IRAMIS/LLB/CEA/CNRS, CEA Saclay, 91191 Gif-sur-Yvette (France); Moncoffre, N. [IPNL/CNRS, Domaine scientifique de la Doua, 69622 Villeurbanne (France); Baldinozzi, G. [CNRS-SPMS/UMR 8580/LRC CARMEN Ecole Centrale Paris, 92295 Chatenay-Malabry (France); Simeone, D. [DEN/DANS/DMN/SRMA/LA2M/LRC-CARMEN, CEA Saclay, 91191 Gif-sur-Yvette (France)

2015-03-25

Highlights: • Interdiffusion at Cr/Si interfaces induced by ion beam mixing at room temperature. • Creation of Cr/Si alloy metastable phases. • Reconstruction of Cr/Si interdiffusion profile by X-ray reflectometry. • Quantitative correlation between Cr and Si profiles extracted from XRR and measured by EDX–TEM. - Abstract: Chromium silicon CrSi alloys are foreseen as possible materials for spintronic devices. Ion beam mixing could be an efficient technique to produce thin films of such alloys at room temperature while avoiding thermal diffusion. In order to assess this point, we have irradiated 20 nm Cr layer on a (1 0 0) Si wafer with 70 keV Kr ions. The X-ray reflectometry technique combined with Transmission Electron Microscopy and Energy Dispersive X-ray analysis was applied to analyze, at the nanometric scale, the formation of Cr/Si blurred interfaces induced by ion beam mixing. From the analysis of reflectivity curves, it appears that nanometric Cr{sub 5}Si{sub 3} and CrSi{sub 2} phases are produced at the early stage of the process. The existence of these two paramagnetic phases gives some clues to explain the reason why the experimentally observed ferrimagnetism was weaker than predicted.

Cr/alpha-Cr2O3 monodispersed spherical core-shell particles based solar absorbers

CSIR Research Space (South Africa)

Khamlich, S

2011-07-01

Full Text Available as reported. The coated Cr/alpha-Cr2O3 spherical particles on rough copper substrates by a simple self-assembly-like method were characterized by scanning electron microscopy, energy dispersive spectrometry, Raman spectroscopy, and diffuse reflectance UV...

Mechanisms of mitochondrial holocytochrome c synthase and the key roles played by cysteines and histidine of the heme attachment site, Cys-XX-Cys-His.

Science.gov (United States)

Babbitt, Shalon E; San Francisco, Brian; Mendez, Deanna L; Lukat-Rodgers, Gudrun S; Rodgers, Kenton R; Bretsnyder, Eric C; Kranz, Robert G

2014-10-17

Mitochondrial cytochrome c assembly requires the covalent attachment of heme by thioether bonds between heme vinyl groups and a conserved CXXCH motif of cytochrome c/c1. The enzyme holocytochrome c synthase (HCCS) binds heme and apocytochrome c substrate to catalyze this attachment, subsequently releasing holocytochrome c for proper folding to its native structure. We address mechanisms of assembly using a functional Escherichia coli recombinant system expressing human HCCS. Human cytochrome c variants with individual cysteine, histidine, double cysteine, and triple cysteine/histidine substitutions (of CXXCH) were co-purified with HCCS. Single and double mutants form a complex with HCCS but not the triple mutant. Resonance Raman and UV-visible spectroscopy support the proposal that heme puckering induced by both thioether bonds facilitate release of holocytochrome c from the complex. His-19 (of CXXCH) supplies the second axial ligand to heme in the complex, the first axial ligand was previously shown to be from HCCS residue His-154. Substitutions of His-19 in cytochrome c to seven other residues (Gly, Ala, Met, Arg, Lys, Cys, and Tyr) were used with various approaches to establish other roles played by His-19. Three roles for His-19 in HCCS-mediated assembly are suggested: (i) to provide the second axial ligand to the heme iron in preparation for covalent attachment; (ii) to spatially position the two cysteinyl sulfurs adjacent to the two heme vinyl groups for thioether formation; and (iii) to aid in release of the holocytochrome c from the HCCS active site. Only H19M is able to carry out these three roles, albeit at lower efficiencies than the natural His-19. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Filtration Markers, Cardiovascular Disease, Mortality, and Kidney Outcomes in Stable Kidney Transplant Recipients: The FAVORIT Trial.

Science.gov (United States)

Foster, M C; Weiner, D E; Bostom, A G; Carpenter, M A; Inker, L A; Jarolim, P; Joseph, A A; Kusek, J W; Pesavento, T; Pfeffer, M A; Rao, M; Solomon, S D; Levey, A S

2017-09-01

Cystatin C and beta-2-microglobulin (B2M) are filtration markers associated with adverse outcomes in nontransplant populations, sometimes with stronger associations than for creatinine. We evaluated associations of estimated glomerular filtration rate from cystatin C (eGFR cys ), B2M (eGFR B 2M ), and creatinine (eGFR cr ) with cardiovascular outcomes, mortality, and kidney failure in stable kidney transplant recipients using a case-cohort study nested within the Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) Trial. A random subcohort was selected (N = 508; mean age 51.6 years, median transplant vintage 4 years, 38% women, 23.6% nonwhite race) with enrichment for cardiovascular events (N = 306; 54 within the subcohort), mortality (N = 208; 68 within the subcohort), and kidney failure (N = 208; 52 within the subcohort). Mean eGFR cr , eGFR cys , and eGFR B 2M were 46.0, 43.8, and 48.8 mL/min/1.73m 2 , respectively. After multivariable adjustment, hazard ratios for eGFR cys and eGFR B 2M mortality; and 9.49 (4.28-21.00) and 15.53 (6.99-34.51; both p mortality, and kidney failure in stable kidney transplant recipients. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Electron transport in all-Heusler Co2CrSi/Cu2CrAl/Co2CrSi device, based on ab-initio NEGF calculations

Science.gov (United States)

Mikaeilzadeh, L.; Pirgholi, M.; Tavana, A.

2018-05-01

Based on the ab-initio non-equilibrium Green's function (NEGF) formalism based on the density functional theory (DFT), we have studied the electron transport in the all-Heusler device Co2CrSi/Cu2CrAl/Co2CrSi. Results show that the calculated transmission spectra is very sensitive to the structural parameters and the interface. Also, we obtain a range for the thickness of the spacer layer for which the MR effect is optimum. Calculations also show a perfect GMR effect in this device.

Spin flip at unelastic scattering of protons with energy near 6 NeV o 50Cr and 52Cr nuclei

International Nuclear Information System (INIS)

Andronov, Yu.F.; Chubinskij, O.V.; Vinogradov, L.I.; Ehl'-Ashri, F.I.; Gustova, L.V.

1978-01-01

Angular S(Q) and energy S(E) dependences spin flip probability S were studied in inelastic scattering of protons with excitation of the 2 1 + states of 50 Cr (Q=-0.782 MeV) and 52 Cr (Q=-1.434 MeV) energy range from 5.6 to 5.95 MeV. In particular, it is elucidated how strongly the behaviour of the spin flip probability depends upon the energy and angle of scattering at Esub(p) approximately 6 MeV for 50 Cr and 52 Cr. Thereby some additional information on specific features of the mechanism of inelastic sccattering by th nuclei is obtained. Measurements were carried out simultaneously in two proton detection channels at scattering angles differing by 30 deg. For targets use was made of self-sustaining enriched foils (87% 50 Cr and 99% 52 Cr). The angular and energy dependences of the spin flip probabilities for 50 Cr and 52 Cr are shown to be rather different: for 52 Cr has a relatively slight energy dependence in the range of a resonance observed in the excitation function; for 50 Cr the behaviour of S(E) undergoes sharp changes. The experimetnal values of S(Q) for sup(50, 52)Cr differ rather strongly from the calculations made on the statistical model and depend considerably upon the scattering angle

P-type Al-doped Cr-deficient CrN thin films for thermoelectrics

DEFF Research Database (Denmark)

Febvrier, Arnaud le; Van Nong, Ngo; Abadias, Gregory

2018-01-01

Thermoelectric properties of chromium nitride (CrN)-based films grown on c-plane sapphire by dc reactive magnetron sputtering were investigated. In this work, aluminum doping was introduced in CrN (degenerate n-type semiconductor) by co-deposition. Under the present deposition conditions, over......-type/n-type thermoelectric materials based on chromium nitride films, which are cheap and routinely grown on the industrial scale....

Development of bovine embryos cultured in CR1aa and IVD101 media using different oxygen tensions and culture systems.

Science.gov (United States)