bluuebunny/crossref_metadata_2025 huggingface dataset:
The synthesis of the 14C and 2H‐isotopomers of (R)‐N‐[2‐(2′‐ethoxyphenoxy)‐ethyl]‐N‐2‐[3‐(4′‐methoxy‐3′‐sulfonamido)‐phenyl]‐propylamine hydrochloride, an α1‐adrenoreceptor antagonist
Authors: Wheeler William J. , Schmiegel Klaus K. , Hunden David C.
Published: October 2006

The synthesis of [14C]‐ and [2H]‐labeled LY253351 (YM12617–1), a potent α1‐receptor antagonist, which is potentially useful in the treatment of benign prostatic hypertrophy (BPH) is described. The [14C]‐isotopomer was synthesized from [14C]‐potassium cyanide in nine steps in 1.5% radiochemical yield. One of the key intermediates, [14C]‐4‐methoxyphenylacetone, was synthesized from [14C]‐4‐methoxyphenylacetyl chloride by a Pd(0)‐catalyzed reaction with tetramethylstannane. The [2H]‐labeled material was synthesized by a Pd/C catalyzed reductive amination with deuterium gas.
Synthesis of radiobrominated m‐tyrosine
Authors: De Jesus Onofre T. , Mukherjee Jogeshwar , Khalifah Raja G.
Published: October 2006

The electrophilic radiobromination of m‐tyrosine was investigated and found to be rapid and quantitative. Two positional isomeric products were found by radio‐HPLC with a mass ratio of 4:1. Because of the inability of proton NMR to unequivocally identify the major product, 13C‐NMR analysis was performed. Results show that the major product was 6‐bromo‐ D,L‐m‐tyrosine. Preliminary studies, in vivo, in mice suggest that radiobrominated m‐tyrosine is a potential tracer for CNS dopamine.
The slow metabolism of L‐[2‐18F]‐fluorophenylalanine in rat
Authors: Murakami M. , Takahashi K. , Kondo Y. , Mizusawa S. , Nakamichi H. , Sasaki H. , Hagami E. , Iida H. , Kanno I. , Miura S. , Itoh I. , Uemura K.
Published: October 2006

The stability of L‐[2‐18F]‐fluorophenylalanine (2‐[18F]‐Phe) was compared with that of natural amino acid, L‐[2,6‐3H]‐Phenylalanine (2,6‐[3H]‐Phe). The mixture of 2‐[18F]‐ and 2,6‐[3H]‐Phe was injected to Wistar rats. The separated arterial plasma was followed by acid treatment and chromatographical analysis. The plasma [18F]‐ and [3H]‐radioactivities decreased with the time and showed the lowest value at 20 min after injection. After that, [3H]‐radioactivity increased significantly up to 60 min, while [18F] ‐ radioactivity remained at the lowest level. The [3H]‐ and [18F] ‐ radioactive macromolecules appeared in the plasma at 10 and 20 min, respectively. In the acid soluble fractions of the plasma and the brain at 60 min, more than 80% of [18F] ‐ radioactivity existed as 2‐[18F] ‐ Phe, while 2,6 ‐ [3H] ‐ Phe was less than 15%. These data suggest the slow metabolism of 2 ‐ [18F] ‐ Phe as compared with that of natural Phe. In conclusion, 2 ‐ [18F] ‐ Phe is suitable to the compartment analysis using positron emission tomography especially at the process of amino acid transport to the brain due to its stability for the period necessary to kinetic analysis.
The synthesis of glycine receptor radioligands [21, 22‐3H] dihydrostrychnine and [2‐3H] strychnine at high specific activity
Authors: Filer Crist N. , Ahern David G.
Published: October 2006

Strychnine (1a) was reduced with tritium gas via heterogeneous catalysis to yield [21, 22‐3H] dihydrostrychnine (2b) at 31 Ci/mmol and via homogeneous catalysis to yield 2b at 50 Ci/mmol. [2‐3H] Strychnine (1b) at 25 Ci/mmol was prepared by the catalytic reductive tritiation of 2‐iodostrychnine (4). Other polyhalo strychnine analogues were synthesized in an attempt to prepare [3H] strychnine at even higher specific activity.
Dimethyl 3,4,5,6‐[2H4] ‐2‐oxoheptylphosphonate: A readily available reagent for the preparation of deuterated prostanoids‐application to the synthesis of2H4‐labelled (±)‐prostaglandin D2
Authors: Meese Claus O. , Holzer Sabine
Published: October 2006

Dimethyl 3,4,5,6‐[2H4]‐2‐oxoheptylphosphonate (1a) was conveniently prepared in two steps from ethyl sorbate and used in a total synthesis of low‐blank (⩽ 0.2%2Ho) 16,17,18,19‐[2H4]‐prostaglandin D2(2a). The required allylic alcohol 15S‐8was isolated by fractional crystallisation of the mixture of R/S epimers and then transformed to a key intermediate, 15S‐silyloxy compound10, by regiocontrolled monosilylation of diol9.
Radiopharmaceutical preparation of a monoclonal antibody, lym‐1, and its F(ab')2 fragment for imaging lymphoma with In‐111
Authors: Mills Stanley L. , Denardo Sally J. , DeNardo Gerald L. , Deshpande Shrikant V. , McCall Michael , Meares Claude , Epstein Alan L.
Published: October 2006

(S)‐4‐[2,3 bis[bis(carboxymethylamino)]propyl]phenyl isothio‐cyanate (CITC) was used to attach In‐111 to an intact monoclonal antibody (Lym‐1) or its fragment F(ab')2 to produce two new radiopharmaceuticals. Immunoreactivity of the Lym‐1, specific for B cell lymphoma, was not affected by the coupling reaction for 1.0 and 4.3 CITC molecules per whole antibody and 3.0 CITC molecules per F(ab')2 fragment. Both retained in excess of 90% immunoreactivity even at the level of 25 mCi of In‐111 per mg of Lym‐1 and 15 mCi per mg F(Ab')2. The labeling reaction produced yields in excess of 98% eliminating the requirement for routine purification of the final radiopharmaceutical.
Synthesis of 14C‐labelled 2‐[4‐(p‐fluorobenzoyl)piperidin‐1‐yl]‐2′‐acetonaphthone hydrochloride (E‐2001‐14C)
Authors: Karibe Norio , Nakamura Takaharu , Mishima Mannen , Sugimoto Hachiro
Published: October 2006

14C‐labelled 2‐[4‐(p‐fluorobenzoyl)piperidin‐1‐yl]‐2′‐acetonaphthone hydrochloride (4), a glutamate release inhibitor for studying the pharmacokinetic profiles of E‐2001, was synthesized in two steps using 2‐bromo‐2′‐[carbonyl‐14C]‐acetonaphthone (1) as the labelled starting material.
Synthesis of 1‐([18O2]‐2‐nitro‐1‐imidazolyl)‐3‐methoxy‐2‐propanol ([18O2]‐misonidazole)
Authors: Yang Chi‐Ching , Goldberg Irving H.
Published: October 2006

A short, efficient synthesis for 1‐(2‐[18O2]‐nitro‐1‐imidazolyl)‐3‐methoxy‐2‐propanol ([18O2]‐misonidazole) from 2‐aminoimidazole is described. The required 18O‐labeled sodium nitrite (82.6 atom %) was conveiently synthesized by the treatment of sodium nitrite with DOWEX 50W (H+) in H218O. When 2‐aminoimidazole reacted with excess of 18O‐labeled sodium nitrite in the presence of sulfuric acid containing copper sulfate in H218O, the 18O‐labeled 2‐nitroimidazole was formed with a reasonable yield (43%). [18O2]‐Misonidazole (70 atom %) was achieved with good yield by the coupling of sublimed 18O‐labeled 2‐nitroimidazole with freshly distilled 1,2‐epoxy‐3‐methoxypropane in ethanol in the presence of a catalytic amount of anhydrous potassium carbonate under reflux for one hour. The desired product was purified by recrystalization and TLC, and characterized by 1H NMR and mass spectra. The 18O content and distribution of synthetic 18O‐labeled misonidazole was determined from the FAB‐MS spectra.
Synthesis and spectroscopic stereospecificity assay of the deuterated quinolizidine alkaloids (2S)‐[2H]‐ and (2R)‐[2H]‐sparteine
Authors: Ebner Thomas , Rebell Jochen , Fischer Peter , Meese Claus O.
Published: October 2006

Borohydride reduction of the (+)−1,2‐dehydrosparteinium salts 2a,b proceeds almost exclusively from the Si side, yielding, respectively, the stereoselectively (2S)(β)‐deuterated (−)‐sparteine 1c from 2a and NaB2H4, and the (2R)(α)‐deuterated (−)‐sparteine 1d from 2b and NaBH4. Stereochemistry and isotopic purity of the deuterium label (≧98%) are established unequivocally by, in conjunction. 1H, 2H, and 13C NMR spectroscopy.
Synthesis of 13C‐labeled verapamil compounds
Authors: Theodore Louis J. , Nelson Wendel L.
Published: October 2006

Two 13C‐labeled verapamil compounds were prepared. 2‐(3,4‐Dimethoxyphenyl)‐2‐isopropyl‐5‐[2–(3,4‐dimethoxyphenyl‐1–[13C]‐ethyl)methylamino]‐valeronitrile was synthesized from 2–(3,4‐dimethoxyphenyl)‐1–[13C]‐ethylamine, which was prepared from 3,4‐dimethoxybenzyl chloride by displacement with 13C‐labeled KCN followed by diborane reduction. 2‐(3,4‐Di‐[13C]‐methoxyphenyl)‐2‐isopropyl‐5–[2–(3,4‐di–[13C]‐methoxyphenethyl)methylamino]‐valeronitrile containing 50% incorporation of 13C in the N‐methyl group was prepared via demethylation of verapamil and subsequent re‐methylation with 13C‐labeled CH3I.
Synthesis of 14C‐labelled 1‐β‐D‐arabinofuranosyl‐E–5–(2‐bromovinyl)uracil (BV‐araU)
Authors: Kumagai Masao , Sakata Shinji , Yamaguchi Toyofumi , Ikeda Kazuyoshi , Machida Haruhiko
Published: October 2006

14C‐Labelled 1‐β‐D‐arabinofuranosyl‐E‐5–(2‐bromovinyl)uracil (BV‐araU) was synthesized in 26.6% radiochemical yield from 1‐β‐D‐arabinofuranosyl‐5‐formyluracil and 14C‐labelled malonic acid for the purpose of the metabolic studies in animals.
The synthesis of E‐β‐[2‐14C] indol‐3‐ylacrylic acid
Authors: Morrison H. , Mohammad Taj , Severns B.
Published: October 2006

We report a two step synthesis of indoleacrylic acid with a 14C‐label in the 2‐position of the indole ring. [2‐14C] Indole was formylated at the 3‐position with phosphorous oxychloride and DMF. Subsequent condensation with malonic acid provided the title compound with specific activity and radiochemical purity of 112 μCi/mmol and 93% respectively.
Synthesis of methotrexate‐1‐15N and methotrexate‐4‐15NH2
Authors: Degraw Joseph I. , Ryan Kenneth J. , Tracy Michael , Colwell William T. , Arnold John R. P. , Roberts Gordon C. K.
Published: October 2006

This paper describes an application of the pterin synthesis of Taylor and co‐workers for preparation of methotrexate specifically labelled at the N1‐ring nitrogen and at the 4‐amino group with 99 atom percent 15N. Oximination of ethyl cyanoacetate‐15N followed by reduction afforded ethyl 2‐aminocyanoacetate‐C15N (3). Condensation with 3‐bromopyruvaldoxime and 4‐methylaminobenzoic acid afforded 2‐amino‐3‐carbethoxy‐5‐N‐methyl‐p‐carboxy‐anilinomethylpyrazine‐1‐oxide‐2‐15NH2 (4). Treatment of 4a with ammonium hydroxide at room temperature gave the 3‐carboxamide (5a). Reduction of the N‐oxide (PCl3), esterification, and dehydration of the amide (POCl3) afforded the 2‐amino‐3‐cyano‐pyrazine benzoate ester (8). Ring closure with guanidine followed by benzoate ester hydrolysis, glutamate coupling and hydrolysis of the glutamate diester yielded methotrexate‐1‐15N (12a). Amination of the unlabeled 2‐amino‐3‐carbethoxy pyrazine intermediate (4b) with 15N‐labelled ammonium hydroxide gave the 15N‐carboxamide (5b) which was carried through the process described above to afford methotrexate‐4‐15NH2 (12b).
A freeze dried formulation for the preparation of 99mTc‐[V]‐DMS complex
Authors: Chiotellis E. , Varvarigou A. , Archimandritis S. , Gyftaki E.
Published: October 2006

A freeze dried kit formulation for the preparation of 99mTc‐[V]‐DMS complex was developed, requiring a single step labeling procedure. Methods of analysis were also developed permitting identification of radiochemical impurities which may be present in radiopharmaceutical solution. 99mTc‐[V]‐DMS prepared by the kit method was evaluated in experimental animals and human volunteers. Data demonstrated that the complex formed after kit reconstitution shows tumor seeking properties. Thyroid medullary carcinoma in patients was successfully detected 2 hrs post administration.
Radiosynthesis of 15O‐labeled hydrogen peroxide
Authors: Takahashi K. , Murakami M. , Hagami E. , Sasaki H. , Kondo Y. , Mizusawa S. , Nakamichi H. , Iida H. , Miura S. , Kanno I. , Uemura K.
Published: October 2006

15O‐H2O2 is thought to be a candidate of attractive injectable tracers for the study of oxygen metabolism with PET. A simple synthetic method yielding 15O‐H2O2 in saline solution by the autoxidation of 2‐ethylanthrahydroquinol with gaseous 15O‐O2 produced by cyclotron target system is described.
Synthesis of [14C]imidazole ring labeled metiamide, cimetidine and impromidine
Authors: Villani A. J. , Petka L. , Blackburn D. W. , Saunders D. , White G. R. , Winster J.
Published: October 2006

The radiosynthesis of imidazole ring labeled [14C]metiamide, [14C]cimetidine and [14C]impromidine are described involving the reaction of the key common intermediate 2‐[[(4‐methyl‐1H‐[2‐14C]imidazol‐5‐yl)methyl]thio]ethanamine (5) with methyl isothiocyanate, dimethyldithiocyanoiminocarbonate/methylamine and the novel dihydroimidazodiazepine (8), respectively. The ring labeled precursor (5) was prepared in five steps from potassium [14C]cyanide in an overall radiochemical yield of 63%, and having a specific activity of 9.3 mCi/mmol.
Synthesis of 11C‐labeled aromatics using aryl chromium tricarbonyl intermediates
Authors: Balatoni Julius A. , Adam Michael J. , Hall Laurance D.
Published: October 2006

Stable and 11C‐arylnitriles have been synthesized in 10 minutes by treatment of substituted fluoroaryl (R=H, p‐Me, o‐Me, p‐Cl) chromium tricarbonyl complexes with stable and 11C‐cyanide in DMSO at 115°–135°. Under the conditions used, decomplexation of the new complex occurs during the substitution reaction liberating the aryl nitrile product without need for the usual oxidative decomplexation step.
Synthesis and preliminary characterization of a new photoaffinity labeled adenosine nucleotide
Authors: Wong Shan S. , Glowacka Danuta , Johnson Dennis R.
Published: October 2006

4‐Azido‐2‐nitrophenyl adenosyl pyrophosphate (ANAP), a new photoaffinity labeled adenosine nucleotide, was synthesized by coupling 4‐azido‐2‐nitrophenyl phosphate and adenosine 5′‐monophosphomorpholidate. Radioactive analogues were prepared from either [14C]‐AMP or iodination of 4‐azido‐2‐nitrophenol. ANAP was shown to be a competitive inhibitor of glucose‐6‐phosphate dehydrogenase against NADP with an inhibition constant of 9.5 μM. Iodination of ANAP did not affect its inhibition. Thus ANAP is a good photoaffinity analogue of NADP. It probably will also serve as an analogue of ATP or ADP.
[14C] acetylation of a glycosaminoglycan sulphate: Sulodexide
Authors: Breccia A. , Gattavecchia E. , Fini A. , Marchi E. , Tamagnone G. F.
Published: October 2006

The synthesis of [14C] labelled Sulodexide is reported. Sulodexide is a sulphated polysaccharide of the class of glycosaminoglycan, containing a heparin like fraction (70%), dermatan sulphate (20%) and other minor fractions. The heparin‐like fraction, suitably isolated from other components, was partially and selectively N‐desulphated, thus making few percent unit ‐NH2groups available for the labelling with [14C]‐acetic anhydride (specific activity 0.15 μCi/mg). Due to the small extent of modification, the sulphate to carboxylate group ratio remained practically unchanged on the heparin‐like fraction. Sulodexide was reconstituted adding to the labelled fraction the suitable amount of the other components; the chemical and biological properties of the final labelled Sulodexide were undistinguishable from those of the starting material.
Synthesis of the tritium labelled ß‐casomorphine analogues3H‐Phe‐Pro‐Gly‐OH and3H2‐Tyr‐Pro‐3H‐Phe‐pyrrolidide
Authors: Oehlke J. , Born I. , Neubert K. , Mittag E. , Niedrich H.
Published: October 2006

The precursor peptides H‐Phe(I)‐Pro‐Gly‐OH (III) and H‐Tyr(I2)‐Pro‐Phe(I)‐pyrrolidide (VIII) were synthesized by stepwise elongation from the C‐terminal end and by coupling of Boc‐Tyr(I2)‐Pro‐OH with H‐Phe(I)‐pyrrolidide and following deprotection of the Boc‐residue respectively. Catalytic dehalotritiation yielded tritated peptides with specific radioactivities of 450 and 1500 GBq/mmol respectively. Cleavage of3H2‐Tyr‐Pro‐3H‐Phe‐pyrrolidide by dipeptidylpeptidase IV resulted in fragments with specific radioactivities of 950 (3H2‐Tyr‐Pro) and 590 GBq/mmol (3H‐Phe‐pyrrolidide).
Towards the control and inhibition of glycation—the role of the guanidine reaction center with aldehydic and diketonic dicarbonyls. A mass spectrometry study
Authors: Saraiva Marco A. , Borges Carlos M. , Florêncio M. Helena
Published: October 2006

Glycation of proteins by glucose and formation of end‐stage adducts (AGEs, advanced glycation end products) has been implicated in pathological mechanisms associated with diabetic complications, macrovascular disease, chronic and renal insufficiency, Alzheimer's disease, and aging. Of the carbonyl containing compounds involved in this process, α‐dicarbonyls have particular importance, being established as direct intermediates in the formation of well‐known AGEs. The guanidino group, present in arginine residues, suffers direct modifications by sugars and its derivatives, and is considered to be an important chemical basis, targeting the control and inhibition of glycation.

Seven dicarbonyl compounds, aldehydic and diketonic, were reacted with guanidine, in an attempt to establish structure/activity relationships. Electrospray mass spectrometry, together with tandem mass spectrometry, was used to identify and characterize the reaction products. The reactivity of guanidine was found to vary with the dicarbonyls used. For glyoxal, a high amount of dihydroxyimidazolidine was formed, whereas for methylglyoxal, dihydroxyimidazolidine was slowly converted into hydroimidazolone. Interestingly, aqueous guanidine was found to prevent argpyrimidine formation. The formation of several amine‐dicarbonyl moieties was observed for the larger alkyl‐diketonic dicarbonyls reaction systems, in particular. Molecular structures, bearing a polar chain, of an imidazole ring, and a nonpolar one, of alkyl groups, located at both sides of the imidazole rings, were attributed to these moieties. Gas‐phase experiments suggested that the larger alkyl groups have a preference for being located at one of the sides of the imidazole rings. Moreover, the referred amine‐dicarbonyl moieties are formed via (dihydroxyimidazolidine − 2H2O) moieties. The latter (dihydroxyimidazolidine − 2H2O) moieties are formed in high amounts in the larger alkyl‐diketonic dicarbonyl reactions. Since these moieties react with dicarbonyl molecules, and react even faster with already modified amine functions, we can foresee that these species may be useful for controlling and inhibiting glycation of larger biomolecules, such as proteins. Copyright © 2006 John Wiley & Sons, Ltd.
Bor‐Verbindungen in der Krebs‐Therapie
Authors: Kliegel Wolfgang
Published: October 2006

Blick von vorn auf die Bestrahlungseinrichtung eines Versuchsreaktors (FRJ‐1) der Kernforschungsanlage Jülich, mit der Neutroneneinfang ‐ Therapieversuche an Tumor‐Mäusen durchgeführt wurden. Man sieht die geschlossene abgeschirmte Ein‐ und Ausladevorrichtung, mit der die Tiere in einem Spezialkäfig bei laufendem Reaktor in einem Transportrohr hinein oder herausbewegt werden können.
Die Glucocorticoide
Authors: Schüppel R.
Published: October 2006

Die Glucocorticoide stellen eine Gruppe von stark wirksamen Arzneistoffen dar, die in der modernen Therapie eine hervorragende Stellung einnehmen. Ihre Wirksamkeit erstreckt sich auf zahlreiche Krankheitserscheinungen, ihre Indikationen sind daher ungewöhnlich breit gefächert. Die Wirkung auf physiologische und pathologische Vorgänge beinhaltet jedoch auch das Risiko beachtlicher Komplikationen und Folgeschäden. Deren Kenntnis und Beachtung bei der Therapie ist für den therapeutischen Erfolg ebenso entscheidend wie die exakte Indikationsstellung.

Die molekularbiologischen und biochemischen Wirkungsmechanismen der Glucocorticoide sind bisher nur teilweise aufgeklärt.
Kleines Fachwörterlexikon Pharmazie und Medizin
Authors: Schütter Reinhold
Published: October 2006

Die Wissenschaft, die sich mit der Erforschung des Ursprungs der Wörter einschließlich der Fachausdrücke befaßt, nennt man Etymologie. Im Griechischen heißt „étymos”︁ wirklich, wahr und „lógos”︁ Darstellung, Kunde, Lehre, Beschreibung. Was sagt nun diese Wissenschaft über die medizinischen Fachbegriffe aus? Hier einige Beispiele.
Der Schlüssel zum Schloß II. Hansch‐Analyse, 3D‐QSAR undDe novo‐Design
Authors: Kubinyi Hugo
Published: October 2006

Die Auffindung neuer Leitstrukturen und ihre gezielte Optimierung sind mehr denn je Kriterien für eine erfolgreiche Arzneimittelforschung. Computergestützte Methoden, wie Hansch‐Analyse, 3D‐QSAR undDe novo‐Design leisten dazu einen wichtigen Beitrag.
Molekulare Ähnlichkeit. 2. Strukturbasierter Entwurf von Wirkstoffen
Authors: Kubinyi Hugo
Published: October 2006

Der Entwurf neuer Wirkstoffe berücksichtigt Kriterien der molekularen Ähnlichkeit. Jede Optimierung einer durch Zufall gefundenen oder gezielt hergestellten Leitstruktur und jedes strukturbasierte oder computergestützte Design neuer Analoga geht von Ähnlichkeitsbetrachtungen der Wirkstoffe bzw. ihrer Komplementarität zu einer Bindestelle aus. Oft dienen natürliche Liganden als Vorbild für die Entwicklung eines Wirkstoffs; in günstigen Fällen stehen die 3D‐Strukturen des biologischen Targets und seiner Liganden‐Komplexe zur Verfügung. Arbeitshypothesen zum Einfluß struktureller Änderungen auf die biologische Aktivität bestimmen den Gang der chemischen Synthesen. Das rationale Design von Wirkstoffen wird an Hand von drei aktuellen Beispielen der industriellen Arzneimittelforschung vorgestellt. Neben der Optimierung der strukturbasiert entwickelten Wirkstoffe wird insbesondere auch die Problematik der Erzielung einer ausreichenden Bioverfügbarkeit behandelt.
Study of the thermal behaviour of alipharomatic polyesters around the glass–rubber transition region by thermomechanical analysis: the mobile and rigid amorphous fraction
Authors: Karayannidis George , Kirikou Eleni , Roupakias Christos , Papageorgiou George
Published: October 2006

The objective of this work was the study using thermomechanical analysis (TMA) of a peculiar behaviour, which was observed some years ago, around the glass–rubber transition region in some thermoplastic alipharomatic polyesters. For this purpose a series of nine alipharomatic polyesters was prepared by the two‐stage melt polycondensation method in a glass batch reactor and subjected to TMA in both penetration and expansion mode. Differential scanning calorimetry (DSC) was additionally used and the results are discussed focusing mainly on the first derivative curve of TMA thermograms in the penetration mode. From this curve, which shows two distinct peaks, the first peak could be attributed to the glass transition temperature (Tg) of the mobile amorphous fraction, since the value coincides with that obtained from DSC and is due to the abrupt shrinkage of the amorphous part of the sample. The second peak (up to 40 °C higher than Tg) is due most probably to the softening of the rigid amorphous fraction and the passage of the polymeric sample from the glass region to the cold crystallization region. When the sample is more crystalline than amorphous then the first peak is smaller or is completely absent. Copyright © 2006 Society of Chemical Industry
Fluorescence resonance energy transfer by quencher adsorption into hydrogels containing fluorophores
Authors: Okawa Kaori , Miyata Takashi , Uragami Tadashi
Published: October 2006

We synthesized anionic hydrogels containing fluorophores and investigated the adsorption of a cationic quencher having an amino group into hydrogels by fluorescence resonance energy transfer (FRET). FRET from the fluorophore to the quencher in hydrogels was examined by fluorescence intensity and fluorescence decay using a fluorescence spectrophotometer and femtosecond laser spectroscopy. The fluorescence intensity of the fluorophore‐containing hydrogels decreased rapidly with increasing amounts of adsorbed cationic quencher. The fluorescence emission of the fluorophore in the quencher‐adsorbed hydrogels containing fluorophores decayed more rapidly than that of the original hydrogels. The aforementioned result indicates that the fluorescence of the fluorophore‐containing hydrogels is quenched due to FRET from the fluorophore to the quencher as the cationic quenchers can approach the fluorophores in hydrogels by electrostatic interactions. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3245–3252, 2006
Structural anisotropy in friction‐deposited layers of polystyrene
Authors: Elzein Tamara , Kreim Virginie , Ghorbal Achraf , Bistac Sophie
Published: October 2006

Friction‐deposited layers of atactic polystyrene (PS) on inert and OH‐grafted gold substrates were the subject of this study to establish a relationship between the friction process and the resulting anisotropy of the transferred polymer chains. We show, by using polarization‐modulation infrared reflection‐absorption spectroscopy that the deposited PS chains involve an anisotropy in which PS main backbone is rather perpendicular to the friction support, fact that is surprising when compared with the majority of polymers where the anisotropy is along the sliding direction. Moreover, our calculation of the orientation angles revealed that PS chains are more perpendicular in the transferred layers than in spin‐coated films. This particular anisotropy is probably due to a parallel reorientation of the phenyl ring on the friction support whatever the surface chemistry is. On the other hand, this study was useful to rectify the assignment of infrared bands unclearly reported in the literature. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3272–3281, 2006
Solvation characteristics of a model water‐soluble polymer
Authors: Hammouda Boualem
Published: October 2006

The model water‐soluble polymer poly(ethylene oxide) was used to investigate solvation characteristics in mixtures of d‐water (deuterated water) and d‐alcohols (deuterated alcohols). Three d‐alcohols have been used: d‐methanol, d‐ethanol, and d‐ethylene glycol. Small angle neutron scattering was used to monitor the solvation properties of poly(ethylene oxide) in the d‐solvent mixtures. Nonideal solvent mixing was observed throughout. Solvent mixtures were found to be more effective solvating agents than individual solvents. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3195–3199, 2006
Structure of gum arabic in aqueous solution
Authors: Dror Yael , Cohen Yachin , Yerushalmi‐Rozen Rachel
Published: October 2006

Gum arabic, a natural polysaccharide derived from exudates of Acacia senegal and Acacia seyal trees, is a commonly used food hydrocolloid. The complex chemical structure of the gum has been widely studied revealing a multifraction material consisting mainly of a highly branched polysaccharide and a protein–polysaccharide complex (GAGP) as a minor component. This work investigates its mesoscopic structure in aqueous solution by small‐angle X‐ray and neutron scattering combined with cryotransmission electrons microscopy. Scattering measurements reveal an intricate shape composed of many spheroidal aggregates assigned to the polysaccharide with a small amount of larger coils. A scattering peak is observed at moderate to high concentrations, the spacing of which exhibits a c−1/3 power law relation to polymer concentration (c). Upon addition of salt, this peak disappears, indicating its electrostatic nature. The large coils contribute a q−2 power law at the low scattering vector (q) range. However, at low concentration in which the interaggregate peak is not observed, a q−1 power law at the low q range indicates the possible existence of a fraction with a locally extended conformation. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3265–3271, 2006
Atmospheric Pressure Glow Discharge CVD of Al2O3 Thin Films
Authors: Hodgkinson John L. , Sheel David W. , Yates Heather M. , Pemble Martyn E.
Published: October 2006

Summary: We report for the first time deposition of aluminium oxide thin films by APGD, plasma‐enhanced CVD. This approach allows deposition at substantially lower substrate temperatures than normally used in atmospheric pressure based processing. The films are analysed by SEM, XPS, RBS, XRD, and optical properties. It is demonstrated that the APGD approach yields films which are essentially smooth, conformal and free from pinholes or other imperfections.

SEM image of alumina film on glass (film G).

magnified image

SEM image of alumina film on glass (film G).
Retracted: Dyeing Behaviour of Low Temperature Plasma Treated Wool
Authors: Kan Chi‐wai , Yuen Chun‐wah Marcus
Published: October 2006

Summary:In this paper, the effects of low temperature plasma (LTP) treatments on the dyeing properties of the wool fibres were studied. The wool fibres were treated with oxygen plasma and three types of dyes commonly used for wool dyeing, namely: (i) acid dye, (ii) chrome dye and (iii) reactive dye, were used in the dyeing process. For acid dyeing, the dyeing rate of the LTP‐treated wool fibre was greatly increased, but the final dyeing exhaustion equilibrium did not show any significant change. For the chrome dyeing, the dyeing rate of the LTP‐treated wool fibre was also increased, but the final dyeing exhaustion equilibrium was only increased to a small extent. In addition, the rate of afterchroming process was similar to the chrome dyeing process. For the reactive dyeing, the dyeing rate of the LTP‐treated wool fibre was greatly increased, and the final dyeing exhaustion equilibrium was also increased significantly. With such results, one could conclude that the LTP treatments improve the dyeing behaviour of wool fibres in different dyeing systems.

SEM picture of an untreated wool fibre.
Calculation of Detonation Velocity, Pressure, and Electric Sensitivity of Nitro Arenes Based on Quantum Chemistry
Authors: Wang Guixiang , Xiao Heming , Ju Xuehai , Gong Xuedong
Published: October 2006

The DFT‐B3LYP method, with basis set 6‐31G*, is employed to optimize molecular geometries and electronic structures of thirty‐nine nitro arenes. The averaged molar volume (V) and theoretical density (ϱ) are estimated using the Monte‐Carlo method, based on 0.001 electrons/bohr3 density space and a self‐compiled program. The detonation velocity (D) and pressure (P) of the explosives are estimated by using the Kamlet–Jacbos equation on the basis of the theoretical density and heat of formation (ΔfH), which is calculated using the PM3 method. The reliability of this theoretical method and results are tested by comparing the theoretical values of ϱ and D with the experimental or referenced values. The theoretical values of D and P are correlated with the experimental values of electric sensitivity (EES). It is found that, for the nitro arenes, there is a linear relationship between the square of detonation velocity (D2) or detonation pressure (P) and electric sensitivity (EES), which suggests that such a theoretical approach can be used to predict or judge the magnitude of EES, which is difficult to measure in the molecular design of energetic materials. In addition, we have discussed the influence of the substituted groups and the parameters of the electronic structure on density, detonation velocity, pressure, and electric sensitivity, and have shown that the substituted groups have the effect of activity or insensitivity, and that the influence of Q‐NO2 and ELUMO is important.
Characterization of Aluminum Powders: II. Aluminum Nanopowders Passivated by Non‐Inert Coatings
Authors: Gromov Alexander , Ilyin Alexander , Förter‐Barth Ulrich , Teipel Ulrich
Published: October 2006

Results of DTA‐TG investigation and chemical analysis of electro‐exploded aluminum nanopowders, passivated and/or coated with the non‐inert reagents: nitrocellulose (NC), oleic acid (C17H33COOH) and stearic acid (C17H35COOH), which were suspended in kerosene and ethanol, amorphous boron, nickel, fluoropolymer, ethanol and air (for comparison), are discussed. Surface protection of aluminum nanopowders by coatings of different origin results in significant advantages in the energetic properties of the powders. Aluminum nanopowders with a protecting surface show increased stability to oxidation in nitrogen, air and in water during storage period. On the basis of the experimental results, a diagram of the formation and stabilization of the coatings is proposed. The kinetics of the interaction of aluminum nanopowders with nitrogen, air and water is discussed. Recommendations concerning the efficiency of non‐inert reagent passivation are proposed on the basis of comprehensive analysis of the experimental data.
Study of Combustion Properties of a Solid Propellant by Highly Time‐Resolved Passive FTIR
Authors: Zhang Liming , Zhang Lin , Li Yan , Liu Bingping , Wang Junde
Published: October 2006

With a time resolution of 0.125 s and a spectral resolution of 4 cm−1, emission spectra of the combustion process of a solid propellant were recorded by highly time‐resolved passive FTIR. Some gaseous combustion products, such as H2O, CO, CO2, NO and HCl, were distinguished by the characteristic emission band of each molecule. The equation for flame temperature calculation based on the diatomic molecule emission fine structure theory was improved through judicious utilization of the spectral running number ‘m’ which makes the temperature measurement simpler and faster. Some combustion information of the solid propellant had been given including the characteristic spectral profile, the distribution of the absolute spectral energy, the distribution of the combustion flame temperature, and the concentration distributions of HCl and NO versus burning time. The results will provide theoretical and experimental bases for improving the formula and raising combustion efficiency of solid propellant, and developing the design of rocket motor, infrared guidance and antiguidance systems.
QSPR Study on the Aqueous Solubility (−lgSw) and n‐Octanol/Water Partition Coefficients (lgKow) of Polychlorinated Dibenzo‐p‐dioxins (PCDDs)
Authors: Yang Guo‐Ying , Yu Jing , Wang Zun‐Yao , Zeng Xiao‐Lan , Ju Xue‐Hai
Published: October 2006

Optimized calculation of 75 Polychlorinated Dibenzo‐p‐dioxins (PCDDs) and their parent compound DD was carried out at B3LYP/6‐31G* level with GAUSSIAN 98 program. The structural parameters identified with the Theoretical Linear Solvation Energy Relationship (TLSER) model were employed as theoretical descriptors in the Quantitative Structure–Property Relationship (QSPR) models derived to predict the aqueous solubility (−lgSw) and n‐octanol/water partition coefficients (lgKow) of PCDDs. The regression model obtained to predict −lgSw contains only one variable: the mean molecular polarizability (α). The best fitted equation for the correlation between −lgSw and α of 12 PCDDs was −lgSw=−3.6425+0.0693α with r2 as 0.9776, Standard Deviation (SD) as 0.30, and suggesting high accuracy of the −lgSw predicting model. At the same time, there exists high correlation (r2=0.8862) between n‐octanol/water partition coefficients (lgKow) and the mean molecular polarizability (α), and the SD is small. The mean molecular polarizability (α) is the only theoretical descriptor used in the QSPR model derived to predict lgKow.
The geometry of logconcave functions and sampling algorithms
Authors: Lovász László , Vempala Santosh
Published: October 2006

The class of logconcave functions in ℝnis a common generalization of Gaussians and of indicator functions of convex sets. Motivated by the problem of sampling from logconcave density functions, we study their geometry and introduce a technique for “smoothing” them out. These results are applied to analyze two efficient algorithms for sampling from a logconcave distribution inndimensions, with no assumptions on the local smoothness of the density function. Both algorithms, the ball walk and the hit‐and‐run walk, use a random walk (Markov chain) to generate a random point. After appropriate preprocessing, they produce a point from approximately the right distribution in timeO*(n4) and in amortized timeO*(n3) ifnor more sample points are needed (where the asterisk indicates that dependence on the error parameter and factors of lognare not shown). These bounds match previous bounds for the special case of sampling from the uniform distribution over a convex body.© 2006 Wiley Periodicals, Inc. Random Struct. Alg., 2007
The aetiology of neurological complications of organic acidaemias—A role for the blood–brain barrier
Authors: Kölker S. , Sauer S. W. , Surtees R. A. H. , Leonard J. V.
Published: October 2006

The blood–brain barrier (BBB) metabolically isolates the central nervous system (CNS) from the circulation and protects it against fluctuations of hydrophilic nutrients in plasma and from intoxication. Recent studies have shown that dicarboxylic acids (DCAs) are transported across the blood–brain barrier at very low rates. In organic acidaemias, neurological complications are common. We hypothesize that, as a result of the very limited efflux, in certain organic acidaemias there is pathological accumulation of DCAs (e.g. glutarate, 3‐hydroxyglutarate, D‐2‐ and L‐2‐hydroxyglutarate, methylmalonate) in the brain secondary to the metabolic block. At high concentrations some of these compounds may become neurotoxic. Treatment should be aimed at preventing the accumulation of these compounds using our understanding of the properties of the BBB.
DETECTING $K$-THEORY BY CYCLIC HOMOLOGY
Authors: LÜCK WOLFGANG , REICH HOLGER
Published: October 2006

We discuss which part of the rationalized algebraic $K$-theory of a group ring is detected via trace maps to Hochschild homology, cyclic homology, periodic cyclic or negative cyclic homology.
Repair of the tricuspid valve in hypoplastic left heart syndrome
Authors: Ohye Richard G. , Gomez Carlen A. , Goldberg Caren S. , Graves Holly L. , Devaney Eric J. , Bove Edward L.
Published: October 2006

The outlook for patients with hypoplastic left heart syndrome has dramatically improved over the past two decades. Universally fatal only 25 years ago, since that time outcomes for staged palliation have shown consistent improvement. Recent reports show that eight to nine patients from every ten can now leave the hospital after the Norwood procedure.1Attrition following the Norwood procedure, nonetheless, remains significant, with from five to fifteen percent of patients dying between the first and second stages of the Norwood sequence.1–4Only three-quarters of the patients undergoing surgery for hypoplastic left heart syndrome survive after five years, even at the centres reporting the best outcomes for the Norwood procedure.1,5In addition to the deaths, some patients are unable to progress through the three stages of reconstruction, and may require cardiac transplantation, or have no options for further therapy. There are many causes for these mortalities and morbidities following the Norwood procedure, including elevated pulmonary vascular resistance, cardiac arrhythmias, coronary arterial insufficiency, right ventricular failure, right ventricular volume overload due to shunt-dependent physiology, and tricuspid valvar regurgitation. Many of these factors are interrelated, and may form feedback loops, which serve to propagate their adverse effects on patients with hypoplastic left heart syndrome.
Monitoring the brain before, during, and after cardiac surgery to improve long-term neurodevelopmental outcomes
Authors: Ghanayem Nancy S. , Mitchell Michael E. , Tweddell James S. , Hoffman George M.
Published: October 2006

Innovation in surgical and medical management of cardiac disease has generated a dramatic improvement in operative survival. Along with these favourable results in terms of survival is the heightened awareness of neurologic complications, which often become evident beyond the early postoperative period. A large, multicentre prospective study found serious neurologic injury occurs in about one-twentieth of patients after myocardial revascularization in adults.1More subtle evidence of persistent cognitive decline and functional impairment has been shown to occur in over two-fifths of such patients.2Acute neurologic abnormalities are reported in up to one-fifth of infants and children who undergo cardiac surgery.3–6Lasting impairments in cognitive, motor, and expressive functioning have been reported in up to three-fifths of children who have undergone complex cardiac surgery during infancy.7Specifically, gross and fine motor delays, visual-spatial problems, language deficits and long-term emotional and behavioural problems have been found.8–13
Anatomic correction of congenitally corrected transposition and its close cousins
Authors: Bove Edward L. , Ohye Richard G. , Devaney Eric J. , Kurosawa Hiromi , Shin'oka Toshiharu , Ikeda Aki , Nakanishi Toshio
Published: October 2006

The congenital cardiac malformation characterized by discordant connections between the atriums and ventricles, as well as those between the ventricles and the arterial trunks, has been given many names. The terms atrioventricular discordance, l-transposition of the great arteries, ventricular inversion, and congenitally corrected transposition have all been used. Regardless of terminology, this complex congenital anomaly has only recently been studied to analyze the long-term effects of its natural history and outcomes following traditional surgical repair of the associated malformations which serve to uncorrect the circulatory pathways. As more patients survive into adulthood, the effects of this condition are now better understood, and the surgical approaches used in the past are being re-examined in light of longer-term follow up.
Molecular basis of inherited skin-blistering disorders, and therapeutic implications
Authors: Aumailley Monique , Has Cristina , Tunggal Lucy , Bruckner-Tuderman Leena
Published: October 2006

Epidermolysis bullosa (EB) and associated skin-fragility syndromes are a group of inherited skin diseases characterised by trauma-induced blistering of the skin and mucous membranes. Mutations in at least 14 distinct genes encoding molecular components of the epidermis or the dermal–epidermal junction (DEJ) can cause blistering skin diseases that differ by clinical presentation and severity of the symptoms. Despite great advances in discerning the genetic basis of this group of diseases, the molecular pathways leading to symptoms are not yet fully understood. Unravelling these pathways by molecular analysis of the structure and in vitro assessment of functional properties of the human proteins involved, combined with genetic models in lower organisms, should pave the way for specific cures for inherited skin fragility.
Ca2+ lightning conveys cell–cell contact information inside the cells
Authors: Hashido Masaya , Hayashi Kenji , Hirose Kenzo , Iino Masamitsu
Published: October 2006

Cells communicate with each other to form organized structures by cell–cell adhesion and cell–cell repulsion, but it remains to be clarified how cell–cell contact information is converted into intracellular signals. Here, we show that cells in contact with neighbouring cells generate local transient intracellular Ca2+ signals (Ca2+ lightning). Ca2+ lightning was observed near cell–cell contact regions and was not observed in the central regions of cells or in solitary cells that were not in contact with other cells. We also show that Ca2+ lightning is able to regulate cell–cell repulsion by means of PYK2, a Ca2+‐activated protein tyrosine kinase, which induces focal adhesion disassembly in a Ca2+‐dependent manner. These results show that cell–cell contact information might be transmitted by Ca2+ lightning to regulate intracellular events.
Differential effects of palmitate and palmitoleate on insulin action and glucose utilization in rat L6 skeletal muscle cells
Authors: Dimopoulos Nikolaos , Watson Maria , Sakamoto Kei , Hundal Harinder S.
Published: October 2006

An increase in circulating levels of specific NEFAs (non-esterified fatty acids) has been implicated in the pathogenesis of insulin resistance and impaired glucose disposal in skeletal muscle. In particular, elevation of SFAs (saturated fatty acids), such as palmitate, has been correlated with reduced insulin sensitivity, whereas an increase in certain MUFAs and PUFAs (mono- and poly-unsaturated fatty acids respectively) has been suggested to improve glycaemic control, although the underlying mechanisms remain unclear. In the present study, we compare the effects of palmitoleate (a MUFA) and palmitate (a SFA) on insulin action and glucose utilization in rat L6 skeletal muscle cells. Basal glucose uptake was enhanced approx. 2-fold following treatment of cells with palmitoleate. The MUFA-induced increase in glucose transport led to an associated rise in glucose oxidation and glycogen synthesis, which could not be attributed to activation of signalling proteins normally modulated by stimuli such as insulin, nutrients or cell stress. Moreover, although the MUFA-induced increase in glucose uptake was slow in onset, it was not dependent upon protein synthesis, but did, nevertheless, involve an increase in the plasma membrane abundance of GLUT1 and GLUT4. In contrast, palmitate caused a substantial reduction in insulin signalling and insulin-stimulated glucose transport, but was unable to antagonize the increase in transport elicited by palmitoleate. Our findings indicate that SFAs and MUFAs exert distinct effects upon insulin signalling and glucose uptake in L6 muscle cells and suggest that a diet enriched with MUFAs may facilitate uptake and utilization of glucose in normal and insulin-resistant skeletal muscle.
Ascorbate removes key precursors to oxidative damage by cell-free haemoglobin in vitro and in vivo
Authors: Dunne Jacqueline , Caron Alexis , Menu Patrick , Alayash Abdu I. , Buehler Paul W. , Wilson Michael T. , Silaghi-Dumitrescu Radu , Faivre Beatrice , Cooper Chris E.
Published: October 2006

Haemoglobin initiates free radical chemistry. In particular, the interactions of peroxides with the ferric (met) species of haemoglobin generate two strong oxidants: ferryl iron and a protein-bound free radical. We have studied the endogenous defences to this reactive chemistry in a rabbit model following 20% exchange transfusion with cell-free haemoglobin stabilized in tetrameric form [via cross-linking with bis-(3,5-dibromosalicyl)fumarate]. The transfusate contained 95% oxyhaemoglobin, 5% methaemoglobin and 25 μM free iron. EPR spectroscopy revealed that the free iron in the transfusate was rendered redox inactive by rapid binding to transferrin. Methaemoglobin was reduced to oxyhaemoglobin by a slower process (t1/2=1 h). No globin-bound free radicals were detected in the plasma. These redox defences could be fully attributed to a novel multifunctional role of plasma ascorbate in removing key precursors of oxidative damage. Ascorbate is able to effectively reduce plasma methaemoglobin, ferryl haemoglobin and globin radicals. The ascorbyl free radicals formed are efficiently re-reduced by the erythrocyte membrane-bound reductase (which itself uses intra-erythrocyte ascorbate as an electron donor). As well as relating to the toxicity of haemoglobin-based oxygen carriers, these findings have implications for situations where haem proteins exist outside the protective cell environment, e.g. haemolytic anaemias, subarachnoid haemorrhage, rhabdomyolysis.
Catalytic by-product formation and ligand binding by ribulose bisphosphate carboxylases from different phylogenies
Authors: Pearce F. Grant
Published: October 2006

During catalysis, all Rubisco (D-ribulose-1,5-bisphosphate carboxylase/oxygenase) enzymes produce traces of several by-products. Some of these by-products are released slowly from the active site of Rubisco from higher plants, thus progressively inhibiting turnover. Prompted by observations that Form I Rubisco enzymes from cyanobacteria and red algae, and the Form II Rubisco enzyme from bacteria, do not show inhibition over time, the production and binding of catalytic by-products was measured to ascertain the underlying differences. In the present study we show that the Form IB Rubisco from the cyanobacterium Synechococcus PCC6301, the Form ID enzyme from the red alga Galdieria sulfuraria and the low-specificity Form II type from the bacterium Rhodospirillum rubrum all catalyse formation of by-products to varying degrees; however, the by-products are not inhibitory under substrate-saturated conditions. Study of the binding and release of phosphorylated analogues of the substrate or reaction intermediates revealed diverse strategies for avoiding inhibition. Rubisco from Synechococcus and R. rubrum have an increased rate of inhibitor release. G. sulfuraria Rubisco releases inhibitors very slowly, but has an increased binding constant and maintains the enzyme in an activated state. These strategies may provide information about enzyme dynamics, and the degree of enzyme flexibility. Our observations also illustrate the phylogenetic diversity of mechanisms for regulating Rubisco and raise questions about whether an activase-like mechanism should be expected outside the green-algal/higher-plant lineage.