bluuebunny/crossref_metadata_2025 huggingface dataset:
In vitro Mutagenesis of Human Dihydropteridine Reductase at the Active Site and at Altered Sites Found in the Reductases of Deficient Children
Authors: Zhang Hong-Ping , Yang Nan , Armarego Wilfred L. F.
Published: March 2013

A general procedure for in vitro site-directed mutagenesis of the wild-type dihydropteridine reductase gene has been used successfully to make eight mutant proteins. Five mutations were at the active site, viz Tyrl50His, Tyrl50Ser, Tyrl50Phe, Tyr150Glu and Tyrl50Lys. The proteins were expressed as glutathione S-transferase fusion proteins from which the unconjugated reductases were obtained by thrombin cleavage. The kinetic parameters of the conjugated and unconjugated reductases were measured using natural quinonoid R-7,8(6H)-dihydrobiopterin and non-natural quinonoid RS-6-methyl-7,8(6H)-dihydropterin and NADH. The kcat (maximum velocity at saturating concentrations of substrates) and kcatl Km (first order rate constant at low concentration of substrates) values show that the phenolic OH of Tyr 150 was the most likely proton source to complete the hydride reduction of the quinonoid pterin cofactor. However in the absence of a proton source at residue 150, measurable enzyme activities were observed indicating that a proton was relayed via a water molecule(s) from some neighbouring acidic amino acid residue. Three mutant dihydropteridine reductases, which were found in defective children, have been similarly attempted, viz GlylSlSer, Gly23Asp and a threonine insertion at position 123. The enzyme activities of the first two mutant reductases were consistent with the severity of the disease. The unconjugated reductase from the third mutation could not be obtained due to proteolysis but the fusion protein was enzymically active.
Varying Folate Pattern in Different Strains of Mice Fed Coconut Oil and Sesame Seed Oil Diet
Authors: Kulkarni Medha V. , Nair C.P. Parameswaran , Viswanathan Gomathy
Published: March 2013

The effect of coconut oil feeding with and without cholesterol on folate metabolism in the two strains of mice, C57BL/6 and AKR have been studied. Liver total folate levels are higher in AKR mice. Coconut oil feeding markedly decreased the ratio of nonmethyl/methyl folates in C57BL/6 strain but not in AKR. Cholesterol supplementation to the coconut oil diet increased the percentage of monoglutamyl folates at the expense of polyglutamyl folates in both strains. Only C57BL/6 strain showed growth retardation on coconut oil feeding. The differences in hepatic folate metabolism between the two strains could possibly have an important role in determining their differences in susceptibility to diet induced atherosclerosis.
5,6,7,8-tetrahydroneopterin (NH4) Acts like an Endogenous Superoxide Dismutase
Authors: Sawada Suguru , Morimoto Takeshi , Kito Tsuyoshi , Taguchi Osamu , Yasumura Mikio , Hirose Hajime
Published: March 2013

The protective effect of 5,6,7,8-tetrahydroneopterin (NH.) against radiation injury in mice was studied. (C57BL/6x A/J)F1 mice received whole body irradiation with a single fatal dose of 8.0 Gy X-ray. NH4 was injected intraperitoneally into irradiated mice at various protocols. NH. was significantly effective to prolong the survival of the irradiated mice. The most effective protocol of NH4 administration was 3 times injections (10 minutes before and after irradiation and additional one 12 hours after that.) with a dose of 30 mg/kg body weight for each. Some mice that received such treatment survived more than 30 days after irradiation. In conclusion, these results indicate that NH4 has an inhibitory potential on radiation injury as an endogenous superoxide dismutase like substance.
A Comparison of Sepiapterin and Tetrahydrobiopterin Uptake by BRL2H3 Cells
Authors: Yamamoto Kazumasa , Nagano Mutsumi , Nakanishi Nobuo , Hasegawa Hiroyuki
Published: March 2013

Cellular uptake of sepiapterin and tetrahydrobiopterin was compared quantitatively with RBL2H3 cells in culture. RBL2H3 is a mast cell line and has the ability to synthesize serotonin. Sepiapterin was incorporated and converted into tetrahydrobiopterin in the cell. The incorporation of sepiapterin was about 10 times faster than tetrahydrobiopterin. A low concentration of tetrahydrobiopterin was incorporated in a saturable manner up to about 10 μM, and it was superimposed upon a linearly concentration- dependent process. Overnight treatment with DAHP depleted endogenous tetrahydrobiopterin. The DAHP treated cells took up tetrahydrobiopterin faster than untreated cells.
Effects of Neopterin on Focal Cerebral Ischemia In Rats
Authors: Arai Toshiyuki , Ishii Hisanari , Mori Hiroko , Mori Kenjiro , Kojima Shuji
Published: March 2013

We examined the effects of neopterin on focal cerebral ischemia induced by transient (2 h) occlusion of the middle cerebral artery (MCA) in rats. Neopterin was administered 10 min before reperfusion (3 mg/kg i.p). The ischemic damage was evaluated one week after the MCA occlusion by magnetic resonance imaging (MRI) and by the immunohistochemical reaction for microtubule-associated protein 2 (MAP2). The ischemic lesion detected by MRI was significantly smaller in the neopterin-treated group than in the non-treated group (n=4 in each group, p<0.05). However, the ischemic neuronal damage determined by MAP2 in the neopterintreated group was not significantly different from that in the non-treated group. Since MRI is thought to reflect the distribution of not only neurons but also glial cells, these results may indicate the effects of neopterin on the glial reaction in focal cerebral ischemia.
Urinary and Serum Pteridines in Liver Diseases
Authors: Mazda Toshio , Iino Teruhiko , Tsusué Motoo
Published: March 2013

The aim of this mini-review is to show the usefulness of pteridines as clinical markers. We assayed urinary neopterin and xanthopterin levels in liver disease. Total pterins were oxidized by active carbon to yield xanthopterin. Urinary neopterin levels were elevated in patients with chronic active hepatitis and in those with chronic persistent hepatitis but not in patients with alcohol-induced liver disease or in those with non-alcoholic fatty liver. Urinary xanthopterin levels were elevated in chronic active hepatitis and alcohol- induced liver disease, but not in chronic persistent hepatitis and non-alcoholic fatty liver. Urinary neopterin levels were high in infectious diseases involving activated cell-mediated immunity, and increased urinary xanthopterin reflects liver-cell damage. We also compared plasma neopterin values in anti-hepatits C virus antibody (anti-HCV) -positive or - negative donors with elevated alanine aminotransferase (ALT). Plasma neopterin values of anti-HCV-negative donors with elevated ALT were the same as those of healthy groups. These results show that the ALT elevation in anti-HCV-negative donors is attributable mainly to steatosis due to excess body weight and/or alcohol consumption, rather than viral infection. During the course of these studies, we were also able to identify esophageal carcinoma in the very early stage by measuring urinary pteridine levels. Our results indicate that pteridines are clinically useful indicators. In particular, neopterin may be used as a means of screening for unknown viral infection.
Regioselective Arylation of 1,3-Dimethyllumazine and Its 5-Oxide by Diazonium Salts
Authors: Sugimoto Takashi , Seo Chihiro , Murata Shizuaki , Pfleiderer Wolfgang
Published: March 2013

A new method to introduce an aryl group directly into the pteridine nucleus by the action of arene diazonium salt in an aqueous alkaline solution is described. 1,3-Dimethyllumazine and benzene diazonium chloride reacts in an aqueous solution at pH 8-9 to give 7 -phenyl-1 ,3-dimethyllumazine together with a little of 6-phenyi-1 ,3-dimethyllumazine. The analogous reactions of 1,3-dimethyllumazine with 4-methyl-, 4-methm.),-, 4-chloro-, and 3-chlorobenzene diazonium chlorides give the corresponding 7-aryl-1,3-dimethyllumazines as major products together with a little of 6-aryl-1,3-dimethyllumazines. Reactions of 1,3-dimethyllumazine 5-oxide with arene diazonium salts under the same conditions exclusively afford the corresponding 6-aryl-1,3-dimethyllumazine 5-oxides which are easily converted to 6-aryl-1,3-dimethyllumazine by the action of tributylphosphine. Mechanisms concerning regioselectivities are investigated by using molecular orbital calculations.
Influence of Three Different Diet Modes Combined with Exercise Loads on Urinary and Plasma Neopterin Concentrations: A Longitudinal Study
Authors: Lamprecht Manfred , Mlekusch Walter , Vrecko Karoline , Reibnegger Gilbert
Published: March 2013

During six months, we studied the influence of three extremely different diet modes (normal diet, carbohydrate- rich diet, fat-rich diet) combined with three defined exercise loads (step test, endurance test fo r 30 minutes, endurance test for 90 minutes) on daily urinary neopterin concentrations of one voluntary subject. Furthermore, plasma neopterin was determmed before, during and after each exercist: load. Each diet period lasted for 28 days and was performed twice : once without, and once with extra supplementation of antioxidants. Urinary neopterin concentrations showed a markedly high daily fluctuation, and there were three occasions with infectious complications which were accompanied by significantly raised uiinary neopterin. Howevt:r, when comparing neopterin levels grouped according to diet mode, absolutely no difference was found. Similarly, neither had supplementation an influence on neopterin, nor could coherent effects of the exercise loads on neopterin be detected. While plasma neopterin concentrations were significantly higher during exercise loads than before and after, the increase was small (about I nmol/l) and might have been due to slight alterations of renal function and/or hemodynamics during the physical exercise . Our study supports the robustness of the immune activation marker neopterin since no influences of these truly extreme diet modes on urinary and plasma neopterin could be detected, and exercise loads had no appreciable influence on urinary as well as plasma neopterin concentrations.
Release of Neopterin, PMN Elastase and Terminal Complement Complexes by Orthotopic Liver Transplantation with and without the Use of Veno-venous Bypass
Authors: Tomasdottir H. , Rønholm E. , Bengtson JP , Bengtsson A.
Published: March 2013

Aim: The aim of the study was to determine whether orthotopic liver transplantation leads to the activation of macrophages, neutrophils and complement. Patients and methods: Twenty-four patients undergoing orthotopic liver transplantation were studied. 12 were operated on with and 12 without the use of a veno-venous bypass. Blood samples for neopterin, PMN elastase and terminal complement complex (SC5b-9) determinations were drawn preoperatively, 1 minute before perfusion of the grafted liver and 2-5 and 30-60 minutes after the start of perfusion of the grafted liver. Comparisons were made between patients with or withour a veno-venous bypass and with or without postreperfusion syndrome (PRS) . PRS was defined as hypotension with ≥30% reduction of systemic mean arterial blood pressure during at least 1 minute after reperfusion of the grafted liver. Results: Release of neopterin was observed 2-5 and 30-60 minutes after the start of perfusion of the grafted liver in patients operated upon with and without the use of a veno-venous bypass. There were no significant differences in neopterin concentration between patients developing PRS and those without circulatory instability. Increased PMN elastase and SC5b-9 concentrations (p<0.05) were found 2-5 and 30-60 minutes after the start of reperfusion in both patients operated upon with and without a veno-venous bypass. The plasma concentrations of neopterin, PMN elastase and SC5b-9 were higher in patients with PRS compared with those without (p<0.05, respectively). Comments: This study indicates that orthotopic liver transplantation leads to the activation of macrophages, neutrophils and the complement cascade. There is no major difference regarding the activation between patients operated upon with and without the use of a veno-venous bypass.
Purification and Characterization of Sepiapterin Deaminase from the Silkworm, Bombyx mori
Authors: Sawada Hiroshi , Kanekatsu Motoki , Nakagoshi Motoko , Dohke Kenjiro , Iino Teruhiko , Takikawa Shin-Ichiro
Published: March 2013

Sepiapterin deaminase has been purified approximately 6,000-told from the larval integument of the lemon mutant of the silkworm by several column chromatographic procedures. Sepiapterin and isosepiapterin were active substrates among various pteridines tested. The molecular mass of this enzyme was estimated to be 74 kDa by SDS-PAGE and 70 kDa by gel filtration, suggesting that the native form of the enzyme is monomeric protein . All silkworm strains, to the best of our knowledge, had an activity of the enzyme and the enzyme was widely distributed in the larval tissues. Sepiapterin deaminase may have an important function on the silkworm.
Altered Tryptophan and Neopterin Metabolism In Cancer Patients
Authors: Iwagaki Hiromi , Hizuta Akio , Nitta Yasuki , Tanaka Noriaki
Published: March 2013

Plasma 5-hydroxytryptamine (serotonin), tryptophan and neopterin levels were measured in patients with depressive cancer cachexia and in healthy controls during the same time period. Patients with advanced cancers had significantly raised neopterin, a marker of endogenous gamma-interferon (IFN-γ) production, but decreased serotonin and tryptophan levels. IFN-γ induces a high level of indoleamine dioxvgenase (IDO), a tryptophan degrading enzyme, which in turn increases metabolism along the tryptophan- nicotinic acid pathway, resulting in decreased synthesis of serotonin. These results suggest that persistent immune activation occur in patients with cancer cachexia, resulting in disorders involving tryptophan metabolism.
Effects of Tetrahydrobiopterin (BH4) on S-Nitroso-N-acetyl-D,Lpenicillamine (SNAP)-Induced HL-60 Cell Death
Authors: Kojima Shuji
Published: March 2013

First, we examined the effects of various chemical NO-donors on the cell damage in HL-60 cells. The most potent of these was S-nitroso-N-acetyl- penicillamine (SNAP). The effect of 5,6,7,8-tetrahydrobiopterin (BH4) on HL-60 cell damage induced by SNAP was investigated. Analysis of electrophoresis of DNA fragmentation induced by SNAP indicated that the cell damage was caused via apoptosis. This phenomenon was observed as early as 5 hr after the treatment with 500 mM SNAP. Apoptosis observed at an early time, 5 hr post-treatment with SNAP, was inhibited by BH4 . However, BH4 significantly increased cell death observed at a later time, 20 hr after the treatment. These results suggest that BH4 may be involved in modulating the cytotoxicity, including cell death, mediated by NO.
Influences of Catecholamine Contents on Tetrahydrobiopterin Metabolism
Authors: Kuzuya Hiroshi , Sakamoto Hideo , Fujita Ko
Published: March 2013

The influence of changes in catecholamine metabolism on tetrahydrobiopterin biosynthesis was investigated in cultured rat pheochromocytoma PC12 cells. The increase in the cellular dopamine content after treatment with the MAO-COMT inhibitor or dopamine produced decreases in the GTP-cy-clohydrolase I (GTPCH-I) activity and total biopterin content. On the contrary, the catecholamine increase after treatment with nerve growth factor produced increases in the GTPCH -I activity and total biopterin content. On the other hand, the decrease in the dopamine content after tyrosine hydroxylase (TH) inhibitor treatment produced decreases in the GTPCH-I activity and total biopterin content, but the catecholamine decrease (the DOPA content increased about 3.4-fold) after aromatic L-amino acid decarboxylase inhibitor treatment produced a decrease in the GTPCH-I activity. These results suggest that an increase in dopamine content that is not directly related to the action of TH plays a role in down-regulation of tetrahydrobiopterin biosynthesis and that when the changes in catecholamine metabolism are strongly associated with the action of TH, tetrahydrobiopterin biosynthesis is regulated depending on the necessity for TH.
Neopterin, Serum Amyloid A, and Cytokine Monitoring After Renal Transplantation
Authors: Neumann M. Christine , Sprenger Hans , Grebe Scott O. , Gemsa Dietmar , Reibnegger Gilbert , Lange Harald , Müller Thomas F.
Published: March 2013

A reliable and early diagnosis of viral infections and rejection episodes is a major goal of immunologic monitoring in transplantation. Soluble markers like the cytokines, neopterin or serum amyloid A are frequently recommended as diagnostic parameters. However they are not often used routinely in transplant medicine. The study investigates the diagnostic value of plasma (P), serum (S), and urine (U) levels of neopterin (S-/U-NEOP), serum amyloid A (SAA), tumor necrosis factor-α, (P-/U-TNF-α), soluble interleukin-2 receptor (P-/U -sIL-2R), and interleukin-6 (U -IL-6) in transplant monitoring and describes an approach for their use in the clinical routine decision making. In 29 renal transplant patients blood and urine samples were collected daily during the posttransplant course on ward. The cytokines were measured by ELISAs, neopterin by RIA, and SAA by immunonephelometry. Descriptive statistics, sensitivity and specificity, day of first significant parameter increase/decrease, receiver operating characteristic curves, and post-test probabilities were calculated for each parameter. 12 acute rejection episodes were diagnosed. As rejection markers, S-NEOP and P-TNF-α had the highest sensitivity, U-IL-6 the highest specificity. 8 viral infections occurred. U-NEOP showed values higher than 1000 μmol/moICrea. It did not exceed this threshold in case of rejection episodes. SAA and U-IL-6 showed peak. levels during rejections but not during episodes of viral infections. Using the calculated likelihood ratio formulas the probability for the occurrence of an acute rejection could be estimated for the individual, daily parameter measurement. Adding the physician IS rating for rejection posttest probabilities were computed. Immunologic monitoring is possible in transplant medicine. Using daily measurements of serum amyloid A and neopterin facilitates the differential diagnosis of acute rejection episodes and viral infections. The likelihood ratio approach permits an application of the parameter monitoring in the clinical routine.
Pteridines CIX
Authors: Abou-Hadeed Khaled , Pfleiderer Wolfgang
Published: March 2013

A simple direct method for the synthesis of lumazine-6,7-diamines (9, 25-27) from uracil-5,6-diamines (10-13) and methyl cyanoformimidate (24) was found. Various nucleophilic displacement reactions were performed with 7-chloro-1,3-dimethyllumazine-6-amine (17) leading to new 6,7-disubstituted 1,3- dimethyllumazine derivatives (18-23).
Inhibition of Mycelial Growth by Methotrexate in Neurospora crassa Wild Type and Mutants Deficient in Folylpolyglutamate Synthase
Authors: Wrishko Rebecca E. , Cossins Edwin A.
Published: March 2013

In mammalian cells, folylpolyglutamate synthase (FPGS) catalyzes the polyglutamylation of methotrexate (MTX), a reaction that significantly enhances the cellular retention and cytotoxicity of this antifolate. In contrast, MTX is a poor substrate for the cytosolic FPGS of Neurospora crassa. The present study has therefore examined the effect of MTX on growth of N. crassa wild type (FGSC 853 ) and two mutants (met-6, FGSC 1330 and mac, FGSC 3609) that have lesions affecting FPGS expression. Mycelial dry weights after growth in MTX-supplemented media, suggested that met-6 and mac were more sensitive to the antifolate than the wild type (WT). MTX concentrations resulting in 50% inhibition of growth (ICso values) were 5.5 11M, 6.0 11M and 87.5 11M for met-6, mac, and WT, respectively. When MTX treatment was followed by transfer to 50 11M folinic acid-supplemented media, growth of both mutants was enhanced by ca. 20% while that of WT increased by ca. 8%. [3H]-MTX pulse-chase experiments demonstrated that all three strains had limited or no ability to form polyglutamates (MTXGlun ) of the antifolate. In WT cultures, supplied with 1 I-tM [3H]-MTX for 24 hr and then grown in MTX-free media for another 24 hr, over 95% of the recovered label was in MTX; MTXGlu2 and MTXGlu3 accounting for only 2% and 1% respectively. MTXGlun derivatives were not detected in mac but low levels of MTXGlu2 were generated by met-6. In all three strains, the level of expression of dihydrofolate reductase (DHFR) was similar. DHFR was purified to apparent homogeneity (21.6 kDa) from extracts of each strain using a protocol of ammonium sulfate fractionation, gel filtration and Matrex Green A chromatography. It is concluded that in Neurospora, MTX polyglutamylation is not a major factor in the cytotoxicity of this antifolate.
Serum Neopterin Assay to Interpret the Main Cause of Chronic Liver Damage Involved with Plural Etiological Factors
Authors: Yoshimoto Satomine , Fukuda Akira , Mazda Toshio , Osawa Nakaaki
Published: March 2013

Identification of the main cause of chronic liver damage (CLD) involved with plural etiological factors is important for the management and the treatment of patients. To evaluate its clinical usefulness in interpreting the main cause of CLD involved with hepatitis C virus, alcoholic overdrinking, or fatty steatosis, which are the most frequent and troublesome etiological facotors in the daily outclinic, serum neopterin level was measured in ten healthy subjects, ten chronic hepatitis C (CH-C) patients, nine alcohol-induced liver damge (AL) patients, eight non-alcholic fatty liver (FL) patients, eight CH-C with AL padtients, seven CH-C with FL patients and ten non-B non-C chronic hepatitis (CH-NBNC) patients by using radioimmunoaasay. There were no significant difierences in the mean serum neopterin levels among the healthy subjects, the AL patients and the FL patients. The serum neopterin level in the CH-C with AL or FL patients was significantly higher than that in the AL or the FL patients and just as high as that in the CH-C patients. Furthermore, serum neopterin level in CH-NBNC patients was as high as that in the patients with CH-C. Therefore, the serum neopterin assay can easily assume the main cause of CLD involved with plural causes, so it will be very useful in the daily clinical practice as an easyto- use auxiliary test.
Experimental Studies of the Effect of Cyclic Mitoguazone Analogues on Antineoplastic Activity of Methotrexate
Authors: Graczyk Julita , Guzowski Grzegorz , Kręźel Izabella
Published: March 2013

In the presented study we tested the effect of the bi- and monocyclic analogues of mitoguazone on neoplastic activity of methotrexate in the model of L1210 leukemia in mice. We have demonstrated that combined therapy involving administration of methotrexate with 2-oxo-propanal bis (4,5,6,7 -tetrahydroIH- l,3-diazepin-2-yl)methylhydrazone dihydroiodide (aM 7) at different doses is more effective than methotrexate monotherapy in mice inoculated with L1210 leukemia.
Characterization of the Protective Effect of Tetrahydrobiopterin Against S-Nitroso-N -Acetyl-D ,L-Penicillamine Induced Endothelial Cell Injury
Authors: Ishii Masakazu , Shimizu Shunichi , Momose Kazutaka , Kiuchi Yuji , Yamamoto Toshinori
Published: March 2013

The purpose of this study was to characterize the protective effect of tetrahydrobiopterin (BH4), one of the cofactors of nitric oxide (NO) synthase, against NO-induced endothelial cell injury. The addition of S-nitroso-N-acetyl-D,L-penicillamine (SNAP), a NO donor, to endothelial cells induced the release of lactate dehydrogenase (LDH), a marker for cell injury. The SNAP-induced endothelial cell injury was markedly reduced by pretreatment with sepiapterin, a precursor of BH4 synthesis. On the other hand, exogenous BH4 had little effect on the SNAP-induced endothelial cell injury. We recently found that NO-induced endothelial cell injury involves a part of H202 production, since the injury was blocked by the treatment with catalase. Although BH4 released reactive oxygen species (ROS) in cell-free conditions, the increase in intracellular BH4 by pretreatment with sepiapterin strongly reduced H202-induced intracellular oxidative stress. These findings suggest that the increase in intracellular BH4 content but not extracellular BH4, strongly attenuates NO-induced endothelial cell injury by at least one of the mechanisms by which BH4 reduces H202-induced oxidative stress. Intracellular BH4 seems mainly to play a role as an antioxidant or as a ROS-scavenger.
Clinical Value of Neopterin In Infectious Complications
Authors: Iwagaki Hiromi , Hizuta Akio , Kobashi Kenta , Isozaki Hiroshi , Takakura Norihisa , Tanaka Noriaki
Published: March 2013

Neopterin, a pteridine intermediate metabolite in the biopterine synthetic pathway, is synthesized and secreted by monocyte/macrophages upon stimulation, mainly by gamma-interferon by activated T cells. C-reactive protein (CRP) is one of the major acute phase reactants and its release is thought to be mediated by interleukin-6. Soluble IL-2 receptor (sIL-2R) is released by activated T cells. Plasma concentrations of neopterin, CRP and sIL-2R were synchronously analyzed in 25 determinations of 5 patients with severe infectious complications. A marked increase in neopterin, CRP and sIL-2R levels was observed. The increase in neopterin was significantly correlated to that of neopterin which is a marker of macrophage activity. These results suggest that macrophages are involved in the stimulation of sIL-2R release. In contrast, the increase in neopterin was not correlated to that of CRP and the lack of correlation between neopterin and CRP indicated that independent mechanisms control the synthesis of these two markers.
Synthesis of L-2-(N-Pteroylamino )-3-(N -phosphonoacetyl)aminopropanoic Acid as an Analogue of the Putative Phosphorylated Intermediate in the γ-Glutamation of Folic Acid by Folylpolyglutamate Synthetase
Authors: Forsch Ronald , Bader Henry , Rosowsky Andre
Published: March 2013

L-2-(N-Pteroyl)amino-3-(N-phosphonoacetyl)aminopropanoic acid was synthesized as an analogue of the putative y-phosphorylated intermediate in the enzyme-catalyzed γ-glutamation of folic acid by folylpolyglutamate synthetase (FPGS). N-(Benzyloxycarbonyl)-L-aspartic acid was converted in four steps to methyl L-2-(N-benzyloxycarbonyl)amino-3-aminopropanoate, and the latter was allowed to react with p-nitrophenyl dimethoxyphosphonoacetate to obtain methyl L-2-(N-benzyloxycarbonylamino)- 3-(N-dimethoxyphosphonoacetyl)aminopropanoate. After catalytic hydrogenation, the resulting amine was coupled to N10-formylpteroic acid via the mixed carboxylic-carbonic anhydride method, and the three ester groups were removed by sequential treatment with Me3SiBr in DMF and NaOH in DMSO. When the last step was performed only with NaOH/DMSO, one of the phosphonate esters remained intact, giving L-2-(N -pteroyl )amino-3 -(N -monOInethoxyphosphonoacetyl )aminopropanoic acid. Also synthesized as a potential FPGS inhibitor was Nα-(4-amino-4-deoxy-N10-methylpteroyl)-Nε-phosphonoacetyl- L-Iysine. The ability of these phosphonoacetyl derivatives to inhibit catalytic addition of L-glutamic acid to folic acid proved to be very low, suggesting that replacement of the CH2C(=O)OP(=O)(OH)2 moiety by NHC(=O)CH2P(=O)(OH)2 may place the terminal phosphonyl group in an unfavorable spatial orientation for binding to the enzyme.
The Importance of Neopterin as a Laboratory Diagnostic Marker of Immune Activation
Authors: Widner Bernhard , Murr Christian , Wirleitner Barbara , Mayr Christiane , Spöttl Nathalie , Baier-Bitterlich Gabriele , Fuchs Dietmar
Published: March 2013

Neopterin is produced and secreted in large amounts by interferon-g stimulated human monocytes/macrophages. Neopterin measurement in urine and semm provides a usefi.ll possibility to estimate the dcgree of ccllular (Thl-type) immune activation, which is directed against viral infections, intracellular bacteria, and certain parasites. Also in malignancy, autoimmw1e diseases and allograft rejection episodes neopterin sensitively reflects the extent of cellular immune activation. Determination of neoptcrin concentrations can be conveniently performed by immunoassay like ELISA or RIA, and HPLC. The major diagnostic applications of neopterin monitoring are: surveillancc of the immw1e status of organ recipients, therapy control and prognosis of diseasc progression in tumor diseascs and HIV infections and also detection of unknown infections in e.g. blood banks. High neopterin levels are strongly associated with oxidative stress, opening an additional application field of ncopterin monitoring to estimate the extent of tissue damagc in the course of immune activation.
Neopterin and Nitrite in Supernatants from Interferon-γ-treated Monocytoid Cell Lines: A Tool to Identify Bacterial Pyrogens
Authors: Peterbauer Anja , Werner Ernst R. , Werner-Felmayer Gabriele
Published: March 2013

The rabbit pyrogen assay identifies pyrogenic contaminations in drugs i.l1tend~d for parenteral use. In order to replace this test because of ethical and economical reasons, various in vitro methods have been developed in recent years. Here, we summarize our results on optimizing a test based on using interferony- treated monocytoid cell lines from man (THP-l) and mouse (RAW264.7). The read-out of the test is neopterin or nitrite, respectively, which is released into the supernatant in response to bacterial compounds. These are costimuli of the enzymes involved in neopterin and nitrite formation, i.e. GTP cyclohydrolase I and inducible nitric oxide synthase. The test reproducibly detects cell wall components from Gram-negative as well as from Gram-positive bacteria and mycobacteria. Furthermore, DNA and cell-free supernatants containing a number of bioactive but not further characterized proteins, both from Staphylococcus aureus, can be detected. Thus, this test is superior over the only in vitro alternative accepted in certain cases, namely the limulus amebocyte lysate assay. Results obtained by measuring neopterin or nitrite correlate well with formation of the endogenous pyrogen tumor necrosis factor-a, a read-out used by some other cell-based in vitro alternatives to the rabbit pyrogen test. We therefore think that the assay presented here has the potential to reduce or even replace the animal test.
Methotrexate in Treatment of Rheumatoid Arthritis
Authors: Wiewiόrowski Maciej , Graczyl Julita
Published: March 2013

Methotrexate is a cytostatic agent used mainly in treatment of neoplasms. However, it has also been applied in treatment of diseases of autoimmune aetiology. The present paper is a review concerning the application of methotrexate in treatment of rhewnatoid arthritis. The authors are trying to determine the role of the drug in the therapy of rheumatoid arthritis at present and in future.
Pteridines CX
Authors: Traub Hermann , Pfleiderer Wolfgang
Published: March 2013

A series of new 6-substituted 2,4-diaminopteridines (3-23) and pterins (26-43) have been synthesized by nucleophilic displacement reactions at the side chain of 6-bromomethyl-2,4-diaminopteridine (2) and 6- bromomethylpterin (25) using various types of 0-, N- and S-nucleophiles. Acid and base hydrolyses allow easy conversion of the 2,4-diaminopteridines (3-5, 7, 9, 10, 12, 19-21 and 23) into the corresponding pterins (26-32, 39-42). Acylations take place at the amino as well as at the functional groups in the side chain (44-46). A versatile protection of the amino group in pterins is its transformation into the N ,N -dimethylaminomethylcnimino function by amide-acetals (47, 50) allowing subsequently selective acylations at the side chain (48, 49).
Characterization and brazing of sintered Ni-Al-Co powder mixtures containing intermetallics
Authors: Yildiz İsmail , Erol Ayhan , Yönetken Ahmet
Published: March 2013

Powder metallurgy is a progressive branch of engineering that enables engineers to fabricate difficult-to-make parts and materials that are used in many industrial areas. Joining this class of materials is a difficult task due to their intrinsic limitations, such as porosity and thermal properties. In this study, varying ratios of Co powder additions to Nix+Aly powder mixture were made prior to sintering at 600°C. The sintered samples were brazed in both microwave and traditional tube furnaces by placing brazing filler alloy between the sintered specimens without added weight at 950°C for 15 min. Scanning electron microscopy and X-ray diffraction techniques were employed to characterize the brazed samples and the joints. Shear strength and hardness of brazed joints were also determined.
Anti-Relativity in Action: The Scientific Activity of Herbert E. Ives between 1937 and 1953
Authors: Lalli Roberto
Published: March 2013

Between 1937 and 1953 the industrial physicist Herbert E. Ives pursued an extended research program with the aim of challenging the acceptance of relativity theories, and became the most important American opponent of Einstein during that era. As part of his anti-relativistic efforts Ives also performed the famous Ives-Stilwell experiment. Usually interpreted as the first direct confirmation of the time dilation formula of special relativity theory, this experiment was regarded by Ives as proof of what he called the Larmor-Lorentz theory. Ives’s heterodox views about relativity were mainly ignored by the scientific community during his lifetime. After his death, however, his criticisms of what the majority of physicists took for granted helped spark philosophical discussions in the late 1950s concerning the conventional stipulation of distant simultaneity in special relativity theory. Ives’s anti-relativistic beliefs and actions allow for an analysis of the heterodox efforts of an accredited member of the scientific community and the subsequent process of his professional marginalization in a specific historical and scientific context. This paper has three aims: to uncover the epistemic roots of Ives’s opposition to relativity; to analyze Ives’s rhetorical strategies and the reasons why he failed to persuade his peers; and to reveal the divergence between the public network of allies Ives built in scientific publications and the hidden network of allies present in his correspondence. It will become clear that the hardening of Ives’s tone against relativity and Einstein can be understood in light of his progressive marginalization and loss of recognized socioprofessional identity due to his unorthodox ideas. Ives’s case is illuminating for the historical, philosophical, and sociological perspectives it provides on the complex mechanisms by which the margins interact with the mainstream of science, both in the production of certified knowledge and in the contextually contingent redefinition and reconfiguration of the boundaries of acceptable scientific discourse.
Comparison of Stresses in Al Lines Under Various Passivations
Authors: Lee S. , Bravman J. C. , Flinn P. A. , Marffib T. N.
Published: March 2013

Thermal stresses in pure Al lines passivated with a baseline 1000Å oxide and additional passivations of 0.5μm oxide, 1μm polymer, or 0.5μm, 1μm, or 2μ nitride were analyzed. Results from finite element analysis and X-ray measurements were compared, and samples were examined in a high voltage SEM for stress voids. For unvoided samples, calculated and measured results showed good correlation, while results for the voided samples showed little correlation due to stress relaxation through voiding. Initial in-situ electromigration test results showed that electromigration voids can occur at stress void sites.
Electrical Activity of B and As Segregated at the Si-SiO2 Interface
Authors: Frühauf Jens , Lindsay Richard , Bergmaier Andreas , Vandervorst Wilfried , Tempel Georg , Maex Karen , Dollinger Günther , Koch Fredericks
Published: March 2013

During spike annealing of ultra-shallow junctions, large fractions of the dopants form a partially active pile-up at the interface between silicon and the screening oxide layer. In this paper, we show results of sheet resistance, SIMS and high resolution Elastic Recoil Detection measurements to investigate the physical and electrical behaviour of B and As dopant atoms at the interface.

Our results show that the fraction of dopants segregated at the interface is as high as 30-50% for B, but is dependent on dose and the type of screening oxide. Concentrations of up to 3e20cm-3 and more of active dopants are found on the Si side of the interface. The presence of nitrogen in the oxide at the interface causes a higher and sharper pile-up. Results indicate that a similar peak is expected for As, with active concentrations above 6e20cm-3. In an HF dip, the pile-up is removed together with the oxide or deactivated during native oxide regrowth.

Further experiments show that immediately after removing the screening oxide in an HF dip the sheet resistance for B decreases sharply due to carrier accumulation, then raises to about 6-9% above the initial level depending on the oxide and dopant species. The sharp decrease in resistance is not observed for As.
Self-Interstitials and Substitutional C in Silicon: Interstitial- Trapping and C– Clustering
Authors: Mirabella S. , Scalese S. , Terrasi A. , Priolo F. , Coati A. , Salvador D. De , Napolitani E. , Berti M.
Published: March 2013

The interactions between self-interstitials (I's) produced by 20 keV silicon implantation, and substitutional carbon in silicon have been studied using a Si1-yCy layer interposed between a near surface I source and a deeper B spike used as a marker for the I concentration. The Si1-yCy layer behaves as a filtering membrane for the interstitials flowing towards the bulk. This trapping ability is related to the total C amount in the Si1-yCy membrane. Substitutional carbon atoms interacting with self-interstitials are shown to trap I's, to be removed from their substitutional sites, and to precipitate into the C-rich region. After precipitation, C atoms are not able to further trap injected self-interstitials. The atomistic mechanism leading to Si-interstitial trapping has been investigated by developing a simulation code describing the migration of injected interstitials. By a comparison with the experimental data it was possible to derive quantitative indications on the trapping mechanism. It is shown that one Si-interstitial is able to deactivate about two C traps by means of interstitial trapping and C-clustering reactions.
Modeling Dislocation Loop Nucleation and Evolution in Germanium, Arsenic and Boron Implanted Silicon
Authors: Avci Ibrahim , Law Mark E.
Published: March 2013

A loop nucleation and evolution model in Si+ implanted Silicon was previously introduced [1]. In this study, the model is extended to predict end of range (EOR) and projected range defect nucleation and evolution created by different ion implant species such as Germanium, Arsenic and Boron. The model assumes that all the nucleated loops come from {311} unfaulting and the loop density and average loop radius follow a log normal distribution. The model is verified with the experimental data obtained from literature for Germanium [2], Arsenic [3] and Boron [4] implanted Silicon for different implant doses and energies. Modeling results are in agreement with the experimental results.
Produção científica brasileira em gestão de operações no período 2000-2010
Authors: Paiva Ely Laureano , Brito Luiz Artur Ledur
Published: March 2013

Este estudo analisa temas e métodos de pesquisa trata-tes nos artigos analisados, houve convergência entre o dos por pesquisadores brasileiros da área de Gestão de que foi publicado pelos autores brasileiros no Brasil e Operações por meio de dois vetores complementares: a nos periódicos estrangeiros, com destaque para supply relevância e o rigor. Inicialmente, contemplaram-se os chain management e estratégia de operações. No que últimos 10 anos das principais revistas brasileiras da área tange ao rigor metodológico, um dos principais desafios de Administração. Complementarmente, analisaram-se presentes é atentar para as mudanças em curso acerca periódicos internacionais mais relevantes da área de de orientação metodológica dos estudos em Gestão de Gestão de Operações. Quanto aos temas mais frequen-Operações no cenário internacional.
Protected environments and substrates for production of genipap seedlings
Authors: Sassaqui Adriano Ribeiro , Terena Tainara Ferreira da Silva , Costa Edilson
Published: March 2013

Genipap (Genipa americana L., Rubiaceae ) is a native Brazilian species and can be used in the recovery of degraded forest areas or for food supply. In order for the species to reach its potential, production of high quality seedlings is essential. The objective of this study was to evaluate genipap seedlings in protected environments and different substrates. The environments tested were: (1) a greenhouse with polyethylene film in the top, with aluminized screen (Aliminet®) of 50%-shading under this film, and lateral sides covered with 50%-shading nylon net (Sombrite®), (2) a shaded hut, all sides covered with 50%-shading nylon net (Sombrite®), and (3) a nursery shelter, with all lateral sides uncovered and the roof covered with leaves of buriti (Mauritia flexuosa). In these environments the following substrates were tested: 50% cattle manure + 50% cassava foliage, 50% cattle manure + 50% Vida Verde®, 50% cattle manure + 50% vermiculite, and 25% cattle manure + 25% vermiculite + 25% of cassava foliage + 25% Vida Verde®. Because there was no repetition of the growth environment, the effect of environment was examined using statistical procedures for analysis of combined experiments. Within environments a completely randomized design was used with five replications. All substrates are suitable for the formation of genipap seedlings, where the recommended substrates are: 50% cattle manure + 50% cassava foliage and 50% cattle manure + 50% Vida Verde® for the greenhouse and the substrates composed of 50% cattle manure + 50% vermiculite and 25% cattle manure + 25% cassava foliage + 25% Vida Verde®+ 25% vermiculite for the shaded hut. The buriti shelter is not recommended for production of genipap seedlings.
Ocorrência de papilomavírus humano na cérvice uterina de mulheres da região ocidental da Amazônia Brasileira
Authors: dos Santos Jéfferson Castro , Cezar Marinês Rodrigues dos Santos , Lisboa Maillene Rodrigues , Moura Maria Manuela da Fonseca
Published: March 2013

A ocorrência do papiloma vírus humano (HPV) é um problema de saúde pública, pois tem sido associado ao câncer. O objetivo da pesquisa foi identificar a ocorrência de papilomavírus humano na cérvice uterina de mulheres da região ocidental da Amazônia Brasileira. O estudo foi realizado na capital de Rondônia, Porto Velho. Foram identificados os tipos de HPV e resultados moleculares foram correlacionados com aqueles os testes colpocitológicos de amostras provenientes de 334 mulheres que realizaram exames preventivos no Sistema Único de Saúde. Obteve-se o material genético viral do papilomavírus humano (DNA-HPV) e o fragmento de 450 pb da região conservada do gene L1 amplificado e submetido à análise do polimorfismo dos fragmentos de restrição (RFLP). Das 334 amostras analisadas, 31% foram confirmados com a presença de material viral (DNA-HPV). Confirmou-se a existência dos tipos: HPVS-16, 18, 33, 53 e 58, que identificam o grupo de alto risco oncogênico com 72% (74/103) de ocorrência, bem como os HPVS-11, 42 e 44 pertencentes ao grupo de baixo risco oncogênico com 28% de ocorrência. Os perfis recorrentes durante o desenvolvimento da análise foram do HPV-16 e -18 com 17% e 16%, respectivamente. Os resultados da pesquisa indicam que mais de 80% das amostras analisadas e que continham material viral não apresentavam nenhuma alteração celular no teste citológico, o que reforça a necessidade de se difundir o uso das técnicas moleculares em diagnósticos convencionais.
Efeitos do tratamento com formalina e sulfato de cobre sobre os parâmetros hematológicos e parasitos monogenéticos em juvenis de Hemigrammus sp. (Osteichthyes: Characidae)
Authors: Paixão Luciana Farias , Santos Rudã Fernandes Brandão , Ramos Fabricio Menezes , Fujimoto Rodrigo Yudi
Published: March 2013

O objetivo deste trabalho foi avaliar a eficácia da formalina e sulfato de cobre no controle de monogenéticos em juvenis de Hemigrammus sp e seu efeito na contagem diferencial de leucócitos. Utilizou-se um delineamento inteiramente casualizado com 5 tratamentos e 3 repetições. Todos os tratamentos tiveram duração de três dias e corresponderam a: T1, controle; T2 e T3 banho por imersão de uma hora em formalina, em duas concentrações uma de 0,25 ml e outra 0,1 ml formalina L-1; o T4, banho de 24 horas com 0,025 ml de formalina L-1; e o T5, banho de 24 horas com sulfato de cobre (0,3 mg L-1). Após o período experimental observou-se que em T2 ocorreu 100% de mortalidade. O T3 e T5 proporcionaram eficácia de 100%, porém os peixes apresentaram intoxicação e mortalidades de 66 e 80%, respectivamente. T4 apresentou eficácia de 77,7% e diminuição dos índices parasitológicos: número total de parasitos de 11,3± 9, intensidade média de infecção de 3,2± 2 e prevalência de 47,1%. Quanto aos leucócitos observou-se que no T3, T4 e T5 ocorreram diferenças na proporção de linfócitos, monócitos e neutrófilos em relação ao controle. O CuSO4 e a formalina reduzem a carga parasitária, mas apresentaram-se tóxicos nas maiores concentrações.
Farinha de folha de leucena (Leucaena leucocephala Lam. de wit) como fonte de proteína para juvenis de tambaqui (Colossoma macropomum CUVIER, 1818)
Authors: Pereira Junior Geraldo , Pereira Filho Manoel , Roubach Rodrigo , Barbosa Paula de Sousa , Shimoda Eduardo
Published: March 2013

O tambaqui (Colossoma macropomum) é um peixe onívoro, natural da bacia amazônica, que possui elevado valor comercial. Características de rusticidade e desempenho produtivo destacam esta espécie para criação em cativeiro. Contudo, em criações comerciais de peixes, os custos com alimentação podem corresponder de 60 a 80% dos custos totais de produção, sendo a proteína o nutriente mais caro da dieta. O objetivo deste trabalho foi avaliar o desempenho produtivo de juvenis de tambaqui alimentados com rações contendo farinha de folha de leucena como fonte protéica. 240 juvenis foram distribuídos em 12 aquários experimentais (350 L), em um delineamento experimental inteiramente casualizado com quatro tratamentos (0%, 8%, 16%, 24% de inclusão de farinha de folha de leucena na ração) e três repetições. Foram determinados o ganho de peso, conversão alimentar aparente, taxa de crescimento específico, taxa de eficiência protéica e custo de produção do quilograma de peso vivo ganho. Para as variáveis estudadas, não houve diferença significativa (p>0,05) entre os tratamentos, indicando que é possível incluir até 24% de farinha de folha de leucena em rações para juvenis de tambaqui, sem comprometimento das variáveis estudadas, embora a substituição não tenha representado redução no custo de produção do quilograma de peixe.
Household food insecurity and excess weight/obesity among Brazilian women and children: a life-course approach
Authors: Schlüssel Michael Maia , Silva Antonio Augusto Moura da , Pérez-Escamilla Rafael , Kac Gilberto
Published: March 2013

Household food insecurity (HFI) may increase obesity risk, but results are not consistent across the life course or between developed/underdeveloped settings. The objective of this paper is to review findings from previous analyses in Brazil among adult women, female adolescents, and children up to five. Data were derived from the 2006 Brazilian Demographic and Health Survey. Associations between HFI (measured with the Brazilian Food Insecurity Scale) and excess weight/obesity were investigated through Poisson regression models. While severe HFI was associated with obesity risk among adult women (PR: 1.49; 95%CI: 1.17-1.90), moderate HFI was associated with excess weight among female adolescents (PR: 1.96; 95%CI: 1.18-3.27). There was no association between HFI and obesity among children (either boys or girls). The nutrition transition in Brazil may be shaping the differential deleterious effect of HFI on body fat accumulation across the life course; the association is already evident among female adolescents and adult women but still not among children.