bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transcatheter closure versus medical therapy of patent foramen ovale and cryptogenic stroke
Authors: Thanopoulos Basil (Vasilios) D. , Dardas Petros D. , Karanasios Evangelos , Mezilis Nicholaos 
Published: October 2006

AbstractObjectives: The purpose of this study was to evaluate the efficacy and safety of device closure of patent foramen ovale (PFO) versus antiplatelet therapy in patients with cryptogenic stroke (CS). Background: There are no controlled data to support the therapeutic value of PFO closure with a device compared to medical treatment in patients with CS. Methods: We performed a nonrandomized, prospective, patient preference case series comparing the recurrence rate in 92 patients with PFO and CS who were treated either with antiplatelet agents (44 patients) or underwent catheter closure (48 patients) using the Amplatzer PFO occluder (APFOO). All patients completed a 2‐year follow‐up. Results: PFO closure group. Immediate complete closure (CC) was observed in 44/48 (91%) patients. Four (9%) patients had a minimal residual shunt immediately after the procedure. One patient developed hemopericardium that was successfully managed by pericardiocentesis. No other complication was observed. Follow‐up. PFO closure group. Contrast bubble study at 6‐month follow‐up confirmed CC in all 48 patients. No complications were observed. Antiplatelet therapy group. Three (6%) and 6 (13%) patients had a major and minor hemorrhagic event, respectively. The average incidence of embolic events/year was 0 and 14.75% for the PFO closure group and the antiplatelet therapy group, respectively (P < 0.001). Conclusions: PFO closure using the APFOO is a rational alternative to medical treatment in patients with CS. Larger randomized clinical trials are required to support the use of this device over the other PFO occluders and medical therapy. © 2006 Wiley‐Liss, Inc.
Update of carotid stent trials
Authors: Daniel George K. 
Published: October 2006

AbstractAs is the case in many vascular territories, endovascular treatment of extracranial carotid artery disease is becoming a rival alternative to surgery. Results of carotid artery stenting (CAS) are improving with the introduction of embolic protection devices, improved technology, and increasing operator experience. Multiple clinical studies have shown results in favor of CAS as opposed to carotid endartrectomy (CEA) in patients considered at high risk for surgery. Current ongoing trials are examining both treatment options in low and intermediate risk patients in prospective randomized protocols. With the recent FDA approval of carotid stent systems, we are entering a new era in the treatment of carotid artery disease. An update of modern carotid stent studies, as well as stent versus surgery studies in the current era is needed. © 2006 Wiley‐Liss, Inc.
Sirolimus for below the knee lesions: Mid‐term results of SiroBTK study
Authors: Commeau Philippe , Barragan Paul , Roquebert Pierre O. 
Published: October 2006

AbstractObjectives: To assess the safety and efficacy of sirolimus‐eluting stents (SESs) in the treatment of severe intermittent claudication and critical limb ischaemia with “below‐the‐knee” lesions, unsuitable for surgery. Background: Limited published evidence suggests that drug‐eluting stents may offer significant improvements in the treatment of infrapopliteal lesions. Methods: Thirty consecutive patients with either severe intermittent claudication or critical limb ischemia (CLI), category 3–6 of Rutherford classification, and multivessel disease of infrapopliteal arteries (≥2 vessels) were treated with SES. Sixty‐two arteries were treated with 106 SES. Mean age was 73.9 years, 77% of patients were male and 36% diabetic. The primary endpoint was clinical improvement and healing of ulcers at short term (1 month) and mid term (7.7 months). The secondary endpoint was primary vessel patency rate (angiographic or duplex assessment). All patients received clopidogrel (75 mg daily) or ticlopidine (150 mg daily) for 2 months or longer. Results: Angiographic and procedural success was achieved in all patients. At 7 months (7.7 ± 5.8), it was necessary to amputate 1 toe in one patient and 1 mid‐foot in another. Limb salvage was obtained in 100% of patients. Other events were: two cardiac deaths unrelated to CLI, one stroke with hemiparesia, one initial reperfusion syndrome, one contralateral CLI, and three recurrent homolateral claudication cases. All surviving patients had a mid‐term clinical improvement with 97% of primary patency (56 patent arteries on 58 arteries). Conclusion: Treatment of “below‐the‐knee” lesions with SES may provide an alternative treatment for patients with CLI. © 2006 Wiley‐Liss, Inc.
Retinoic acid is required for endodermal pouch morphogenesis and not for pharyngeal endoderm specification
Authors: Kopinke Daniel , Sasine Joshua , Swift Jennifer , Stephens W. Zac , Piotrowski Tatjana 
Published: October 2006

AbstractLateral view of the head of a 30 hours post fertilization Tg(foxd3:gfp) zebrafish embryo expressing GFP in neural crest cells which will differentiate into pigment cells and cells in the pharyngeal arches (anterior is pointing up). The embryo is double labeled with the antibody Zn8 in red, which labels four endodermal pouches in between neural crest filled pharyngeal arches, as well as sensory ganglia. See Kopinke et al., Developmental Dynamics 235:2695–2709, 2006. © 2006 Wiley‐Liss, Inc.
Synthesis of a 2D Lander
Authors: Basu Chaitali , Barthes Cecile , Sadhukhan Subir K. , Girdhar Navdeep K. , Gourdon André 
Published: October 2006

AbstractA method for the preparation of an asymmetric superbenzene is presented. The synthesis proceeds through the 12‐fold cyclodehydrogenation of a polyaromatic precursor obtained by successive Diels–Alder additions of cyclopentadienones and alkynes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Preparation, prevention, and response: Data elements and data bases for support
Authors: Allard Celia , Langston Ira W. , Schmidtlein Frank A. 
Published: October 2006

AbstractCampuses should act on salary equity issues before litigation arises. Campuses must resolve data base problems, unfocused studies, problems in data interpretations, and constraints on implementing findings if they are to take timely actions.
Editor's notes
Authors: Schiltz Michael E. 
Published: October 2006

AbstractIn the evolution of every profession, there comes a time when its practitioners begin to examine formally those characteristics that underlie the craft's claim to professional status. Institutional researchers have been meeting now in formal gatherings for over a quarter century, and it is not surprising that attention is more frequently being paid to such characteristics. We are entering a period in which institutional research is becoming conscious of its professionalism as a formal subject of inquiry.
Academic program review in planning, budgeting, and assessment
Authors: Barak Robert J. , Sweeney Janet D. 
Published: October 2006

AbstractThis chapter draws on the results of a national study of public and private two‐ and four‐year higher education institutions to examine the use of program review in institutional planning, budgeting, and student outcomes assessment. We also discuss the reasons for the success or lack of success of program review.
Publishers' perspectives: Guidebooks
Authors: Hoeritz Kimberly J. , Corderman Allan B. , Reed Max , Fiske Edward B. 
Published: October 2006

AbstractCollege guidebook publishers have come under great scrutiny as the number of such publications has increased. The burden of survey response is felt by the institutions who are called upon to fulfill various requests for information, often involving a number of formats. In this chapter, four major publishers of college guidebooks respond to the issues raised in the previous chapters.
Synthesis of 14C‐labelled 1‐(2,6‐dimethyphenylamino)‐2‐dimethylamino‐propane
Authors: Zólyomi G. , Zubovics Z. , Toldy L. 
Published: October 2006

AbstractThe antiarrhytmic 1‐(2,6‐dimethylphenylamino)‐2‐dimethylamino‐propane (6a) was labelled with 14C for pharmacokinetic study. A convenient synthesis, using 2‐bromopropionyl‐1‐14C chloride as radioactive key intermediate, involving an improved method for the reduction of N‐(2‐dimethylaminopropionyl)‐2,6‐dimethylaniline (8) was elaborated.
Synthesis of (2H5) indole‐3‐pyruvic acid
Authors: Badenoch‐Jones Jane , Summons Roger E. , Letham David S. 
Published: October 2006

AbstractA method for the synthesis of deuterium‐labelled tryptophan and its enzymatic conversion to indole‐3‐pyruvic acid ((2H5)IPYA) using amino acid oxidase is described. (2H5)IPYA can be used as an internal standard for the quantitation of IPYA by mass spectrometry in plant extracts and for estimating the breakdown of IPYA to indole‐3‐acetic acid (IAA) during sample extraction and purification. When used in conjunction with (2H2) IAA, (2H5) IPYA should allow more accurate quantitation of IAA in plant extracts.
A new synthetic route for preparing 14C‐labelled aminogutethimide
Authors: Askam V. , Eweiss N. , Nicholls P. J. 
Published: October 2006

AbstractA new route for preparing aminoglutethimide labelled at C5 (Scheme I (10)) with 14C is described, which offers the advantage of introducing 14C at a late stage in the synthesis.
Synthesis of [2‐13C]phenol (1)
Authors: Yuan Sun‐Shine , Ajami Alfred M. 
Published: October 2006

Abstract[2‐13C]cyclohexanone was synthesized through [13C]cyanation of cyclopentanone followed by acetylation, reduction and ring expansion. Treatment with cupric bromide/lithium bromide and dehydrobromination of the resulting labeled 1,6‐dibromohexanone in a “one pot” procedure gave [2‐13C]phenol.
Ein Verfahren zur Herstellung von Mehrfach mit Tritium Markiertem Thymin BZW. Thymidin
Authors: Pleiß U. , Römer J. 
Published: October 2006

AbstractAfter a survey about the preparation of tritium labelled thymine and thymidine a new synthesis for the preparation of manifold labelled thymine respectively thymidine is given. 5‐Formyluracil was reduced to 5‐hydroxymethyluracil (5‐HMU) in a phosphate buffer at pH 7,0 with tritium gas using Pd0/BaSO4 as catalyst. The tritium labelled 5‐HMU was hydrogenated to [4methyl‐3H] thymine with tritium gas using a mixture of Palladium black and Palladiumchloride in dry dioxane. The specific activity was 2550 GBq/mmol. [methyl‐3H] Thymidine was obtained in a usual enzymatic synthesis.
Synthesis of iodine‐125 labelled analogues of metyrapone and metyrapol
Authors: Hays Sheryl J. , Mangner Thomas J. 
Published: October 2006

AbstractMetyrapone (1) and metyrapol (2) are potent and reversible inhibitors of the 11β‐hydroxylase enzyme system of the adrenal cortex. Iodine‐125‐labelled derivatives of 1 and 2 were required for biodistribution studies. Utilizing a new exchange procedure these radioiodinated analogues were synthesized with radiochemical yields ranging from 24‐100% and specific activities as high as 1.72 Ci/mmol.
Synthesis of deuterated methylenecyclohexanes, methylenedecalins and taraxasterols
Authors: Lee Hsiu‐Pu Daniel , Eichmeier Larry S. , Piatak David M. 
Published: October 2006

AbstractTaraxasterols specifically labelled at various ring E sites were synthesized as were cyclohexanes and decalins substituted by a methyl group and an exocyclic methylene moiety similar to the ring Esystem of this terpene. Preparation of deuterated analogs in which the deuterium is located beta to the exocyclic double bond was accomplished by catalytic reduction of the corresponding unsaturated ketone, followed by removal of the label at the alpha carbon and introduction of the exocyclic methylene with a Wittig reaction. Compounds labelled on the exocyclic methylene moiety were afforded by a Wittig reaction of the appropriate ketone with (methyl‐d3)triphenylphosphonium bromide. Taraxasterol trideuterated alpha to the double bond was prepared by DC1 exchange of the ketone followed by a Wittig reaction.
Partial synthesis of [6α‐3H]gibberellin‐A3 of high specific activity
Authors: Lischewski M. , Pleiß U. 
Published: October 2006

AbstractThe phytohormone gibberellin‐A3 was tritium‐labelled by a chemical route. The specific activity of the [6α‐3]‐gibberellin‐A3 obtained was 22.5 Ci/mmol.
Synthesis of phenyl‐3H‐sec‐butyl‐35S1‐disulphide
Authors: Ayrey G. 
Published: October 2006

AbstractPhenyl‐3H‐sec‐butyl disulphide was synthesized via Wilzbach irradiated phenyl benzenethiolsulphonate and phenyl‐sec‐butyl‐35S1‐disulphide was synthesized via elemental sulphur‐35. The two disulphides were mixed to give phenyl‐3H‐sec‐butyl‐35 S1‐disulphide which was assayed by liquid scintillation counting.
Isotopic discrimination between 3H and 14C in vitro during enzymatic phosphorylation of labelled thymidine
Authors: Baugnet‐Mahieu L. , Goutier R. , Semal M. 
Published: October 2006

AbstractWe compare the phosphorylation of 6‐3H‐TdR and 2‐14C‐TdR to TMP, TDP and TTP by tissue extracts and to TMP by purified kinase preparations. The rate of phosphorylation of 6‐3H‐TdR is only 0.6 to 0.8 that of 2‐14C‐TdR. The same isotopic discrimination exists between methyl‐labelled thymidines. In mixtures of 3H‐TdR and 14C‐TdR incubated together with a liver extract, the isotopic ratio is lower in the products than in the substrate. Degradation products of 3H‐TdR do not seem to interfere with enzymatic activity. This isotopic discrimination is tentatively ascribed to an isotopic effect of 3H which is mainly detectable at the high substrate/enzyme ratios prevailing in the in vitro incubation conditions.
Synthesis of L‐ascorbic‐4‐3H acid
Authors: Bell E. M. , Baker E. M. , Tolbert B. M. 
Published: October 2006

AbstractA method is presented for preparation of L‐xyloascorbic‐4‐3 H acid 9.5μC/mg by the exchange of 8 M dipotassium ascorbate in tritiumlabeled water by heating 20 hours at 100°C The data confirms the assumptions of Brenner (8), that alkaline isomerization of ascorbic acid proceeds through a carbanion on carbon‐4. A study of the radiation stability of crystalline ascorbic acid indicates that it is not unusually radiation sensitive.
Studies on the tritium labelling of some local anaesthetics and amino acids by the microwave discharge modification of the Wilzbach technique
Authors: Gosztonyi T. , Walde N. 
Published: October 2006

AbstractSome local anaesthetics and amino acids were labelled with tritium by the microwave discharge modification of the Wilzbach technique.The following substances were investigated: local anaesthetics: carbocaine, citanest, l‐cocaine, tetracaine and xylocaine; amino acids: glycine, DL‐α‐alanine, DL‐Leucine, DL‐phenylalanine and DL‐tryptophane.The range of microwave energy used was 4,000 to 270,000 Wsec. The range of specific activities obtained was from 0.2 to 29.4 mC/mM; and for the most used substance, DL‐leucine, from 0.4 to 27.2 mC/mM.The effects of some reaction parameters on the labelling were investigated. Results obtained are discussed.
Preparation and analysis of isotopically pure tetratritiated methane
Authors: Ciranni G. , Guarino A. 
Published: October 2006

AbstractMany difficulties are encountered in the preparation of multilabelled coumpounds, as their purification and analysis for isotopic purity are involved. Another major problem is their self‐radiolysis which can change their composition during storage.This paper describes the preparation of CT4 and the analyses which were carried out in order to check its purity : i.e. the mass spectrometric assay and a new gas chromatographic technique employing as detector an ionization chamber coupled with a vibrating reed electrometer. These analyses confirmed the isotopic purity of the CT4 prepared, the main impurity being CHT3.
Synthesis of carbon‐14 labelled S‐ethyl hexahydro‐1H‐azepine‐1‐carbothiolate
Authors: Gutman A. D. , Baker D. R. , Brokke M. E. 
Published: October 2006

AbstractS‐Ethyl hexahydro‐1H‐azepine‐1‐carbothiolate labelled in the ethyl moiety and in the azepine ring with carbon‐14 was prepared to facilitate residue and metabolism studies. The ethyl labeled compound was prepared in 86% yield and 99+% radiochemical purity. The azepine labeled material was prepared in 60% yield and 99+% radiochemical purity.
Spezifische Markierung kristallisierter Leucinaminopeptidase mit Managan‐54
Authors: Fittkau S. , Kettmann U. , Hanson H. 
Published: October 2006

AbstractDas Protein “Leucinaminopeptidase” kann aus Rinderaugenlinsen kristallisiert werden und ist durch Magnesium‐ und Manganionen aktivierbar. Wird einem Kristallisationsansatz 54MnCI2 zugesetzt, so sind die gewonnenen Enzymkristalle radioaktiv. Bei einem wahrscheinlichen Molekulargewicht der Leucinaminopeptidase von 325.000 findet man einen Gehalt von 4‐5 Atomen Mangan pro Enzymmolekül. Das Metall ist fest gebunden und läβt sich weder durch Fraktionierung an Sephadex G 25 noch durch kontinuierliche Dialyse bei p H 8 gegen Trispu ffer entfernen.Die Markierung der Leucinaminopeptidase mit 54Mn kann auch durch einfache Inkubation der Enzymlösung mit Manganchlorid erfolgen. Das überschiissige, nicht‐proteingebundene Metall wird an einer Sephadex‐Säule quantitativ abgetrennt.Weiter wurde die Bindungsfähigkeit der Leucinaminopeptidase für Zn‐ und Co‐lonen in Abhängigkeit vom pH ‐ Wert und der Metallionen‐Konzentration hestimmt.
Tritiations by HTO promoted aluminium chloride. IV. Cyclohexane and n‐heptane
Authors: Mǎntescu C. , Genunche A. , Dutǎ‐Cristu D. , Balaban A. T. 
Published: October 2006

AbstractTritium labelling of saturated hydrocarbons (n‐heptane, cyclohexane) is conveniently performed on a small scale by isotopic exchange with tritiated water in the presence of aluminium chloride. The reaction involves hydride ion abstraction but is not accompanied by isomerization, unless the reaction conditions are rather severe. The activities of cyclohexane, and of the methylcyclopentane formed by its isomerization, were found to be comparable.
Preparation of bis‐/2‐chloroethyl‐1,2‐3H/methylamine hydrochloride
Authors: Filip J. 
Published: October 2006

AbstractBis‐(2‐chloroethyl‐1,2‐3H) methylamine hydrochloride was prepared. The starting product was acetylene‐1,2‐3H which was selectively hydrogenated to ethylene‐1,2‐3H. It was observed that on reduction with chromium (II) chloride solution in dilute hydrochloric acid the isotopic exchange with acetylene‐1,2‐3H is negligible. Ethylene was converted to ethyleneoxide‐1,2‐3H by the usual method. Ethyleneoxide‐1,2‐3H can be used for synthesis of several labelled halogenalkylamines and as the starting compound for other syntheses.
Tritium labelling of amino‐acids and peptides by the Wilzbach method. II. Racemization of amino‐acids during exposure to tritium gas
Authors: Parmentier J. H. 
Published: October 2006

AbstractOptically pure amino‐acids were labelled with tritium by the Wilzbach method. The percentage of radioactivity found in the opposite enantiomer was determined by reverse dilution analysis. After tritiation of L‐phenylalanine, D‐phenylalanine, L‐tyrosine, L‐proline, D‐proline, L‐glutamic acid and L‐alanine respectively 2.7, 2.2, ≤ 1.1, 4.6, 4.0, 11.9 and 19.3 of the activities of the radiochemically pure amino‐acids were found in D‐phenylalanine, L‐phenylalanine, D‐tyrosine, D‐proline, L‐proline, D‐glutamic acid and D‐alanine.Wilzbach labelling ol phenylalanine caused the formation of a considerable amount of a radiochemical impurity that was identified as β‐cyclohexylalanine.
The radiopurity of S‐adenosylmethionine and S‐adenosylethionine preparations
Authors: Schlenk F. , Zydek C. R. 
Published: October 2006

AbstractIn the biosynthesis of labeled S‐adenosylmethionine and S‐adeno‐sylethionine from the corresponding 14C‐labeled sulfur amino acids by yeast, some radioimpurity occurred by non‐specific labeling of the sulfonium compounds. This is explained by partial degradation of methionine and ethionine in the yeast cells, followed by utilization of the randomized fragments in the biosynthesis. The degree of mislabeling remains low because endogenous methionine synthesis from metabolic pool constituents is suppressed by the excess of methionine and ethionine supplement in the culture medium. Hydrolysis of the sulfonium compounds and analysis of the fragments showed that the misplaced isotope amounts to approximately 0.5% in the adenine, and 0.2% in the homoserine part compared with the total radioactivity of the sulfonium compounds (100%).
Recent developments in the mechanism of the protection effect of aromatic compounds on the radiolysis of aliphatics
Authors: Ekstrom A. , Garnett J. L. 
Published: October 2006

AbstractThe proposed mechanisms by which aromatic compounds protect aliphatic materials from enhanced radiolytic decomposition are reviewed. Recent developments in this field using the radiolysis of methanol‐benzene as a typical system are discussed. Emphasis has been placed on the identification and isolation of the scavenging products from methanol‐benzene also the chemical fate of the added benzene. Isotope effects have been used to elucidate possible mechanisms of formation of the scavenging products. The application of the results of this study to the problem of self‐destruction of radioactive compounds is discussed. An interpretation of the mechanism of the protection effect in terms of the storage of labelled molecules is made.
Chlorisotopenaustausch bei organischen Verbindungen, I Flüssigkeitsszintillationstechnik und Flüssigkeitszählrohr zur Aktivitätsbestimmung organischer Chlorverbindungen‐(36Cl)
Authors: Kirchhoff Klaus , Boberg Friedrich , Schultze Georg Richard 
Published: October 2006

AbstractEs werden vergleichende Untersuchungen zur Aktivitätsbestimmung bei Hexachlorpropen‐(36Cl) und Trichloracrylsäure‐(36Cl) mitgeteilt. Die Messungen erfolgen im Geiger‐Müller‐Flüssigkeitszählrohr mit Zählgerät und mit einem Zweikanalflüssigkeitsszintillationsgerät. Die relativen Messfehler betragen ±0,9% beim Flüssigkeitszählrohr und ±0,6% beim Flüssigkeitsszintillationsgerät. Für die Zählrohrmessung werden Eigenabsorption der Substanz und Totzeit mit Hilfe empirischer Korrekturen eliminiert.Für Messungen mittels Flüssigkeitsszintillationsgerät wird der Löscheffekt empirisch eingeeicht. Für 36Cl ist die Wirkung des Löscheffektes von Hexachlorpropen, Heptachlorpropan, Trichloracrylsäure, Äthylenglykol, Methylalkohol, Tetrachlorkohlenstoff und Tetrachloräthylen durch Verstärkungserhöhung zu kompensieren, wie experimentell gezeigt wird.Der Löscheffekt vom 4.5‐Dichlor‐1.2‐dithia‐cyclopentenon‐(3) kann aber nicht kompensiert werden. Die Wirkung von Netzspannungsschwankungen, Füllhöhenänderungen und Einwaagefehlern wird untersucht.
Isotopic exchange of active methyl hydrogens. V. (1) Reactivity of α‐ and γ‐methyl groups and β‐hydrogens in pyrylium salts
Authors: Gǎrd Eugenia , Vasilescu Alice , Mateescu G. D. , Balaban A. T. 
Published: October 2006

AbstractThe deuteration and dedeuteration of 2,4,6‐trimethylpyrylium perchlorate in water (D2O and H2O, respectively) was studied by nuclear magnetic resonance using as a quantitative standard for protons tetramethylammonium bromide. γ‐Methyl groups exchange faster than α‐methyl groups; β‐standing hydrogens exchange very slowly. A mechanism involving anhydrobase and pseudobase formation is discussed and theoretical calculations are mentioned. Geminal hydrogen‐deuterium spin‐spin coupling in incompletely deuterated methyl groups is observed.
Versuche zur Synthese von Glutamat‐2‐T
Authors: Wenzel M. , Brühmüller M. , Engels K. 
Published: October 2006

AbstractGlutaminsäure wurde durch Austauschreaktionen in HTO mit Tritium markiert. Bei der Austauschreaktion nach intermediärer Azlacton‐Bildung mit Essigsäure wird 1‐Glutamat racemisiert. Der Tritium‐Einbau ist gering und erfolgt nicht am C2‐Atom, wie durch enzymatischen Abbau mit Glutamat‐Dehydrogenase bewiesen wurde. Mit Hilfe von Transaminase gelingt es dagegen, spezifisch 1‐Glutaminsäure in Position 2 zu markieren und die spezifische Aktivität des eingesetzten HTO zu erreichen.