bluuebunny/crossref_metadata_2025 huggingface dataset:
Interactions among nitric oxide and Bcl‐family proteins after MPP+ exposure of SH‐SY5Y neural cells II: Exogenous NO replicates MPP+ actions
Authors: Dennis Jameel , Bennett James P.
Published: March 2003

In the preceding companion article, we showed that the neurotoxin methylpyridinium (MPP+) increases mitochondrial nitric oxide (NO), causes a post‐transcriptional, NO‐dependent increase in Bax protein and produces caspase‐dependent apoptosis and caspase‐independent cell death. In the present study, we show that exogenous NO replicates these findings. The long‐term NO generator diethylenetriamine‐NO (DETA‐NO) reproduced the post‐transcriptional Bax protein increase, but did not increase Bcl‐2 or Bcl‐XL proteins. Like MPP+, DETA‐NO caused an early decrease in Bcl‐2 mRNA, did not increase Bax protein in ρ0 cells and caused caspase‐ and cycloheximide‐dependent apoptosis and caspase‐independent cell death. We developed cell lines with inducible overexpression of Bcl proteins, at levels relevant to those we found in cells exposed to MPP+ or DETA‐NO. Inducible overexpression (∼2‐fold) of Bcl‐2 or Bcl‐XL proteins reduced MPP+ or NO‐induced apoptosis but did not affect cell death. Inducible Bax overexpression (∼5‐fold) slightly increased cell death. Our results show that exogenous NO mimics actions of MPP+ on SH‐SY5Y neuroblastoma cells and supports the mediation of MPP+ neurotoxicity by NO generated intracellularly in mitochondria. © 2003 Wiley‐Liss, Inc.
Involvement of the α7 subunit of the nicotinic receptor in morphogenic and trophic effects of acetylcholine on embryonic rat spinal motoneurons in culture
Authors: Catone Christelle , Ternaux Jean‐Pierre
Published: March 2003

The morphogenic and trophic effects of acetylcholine (ACh) on embryonic cultured rat spinal cord motoneurons (MNs) through nicotinic α7 autoreceptors were assessed. α7 Subunits of the nicotinic cholinergic receptor were detected in cultures of purified rat spinal embryonic MNs sampled at E15, by both immunocytochemistry and α‐bungarotoxin binding. According to these two methods, α7 subunits are located mainly at somatic and axonal membrane. Functional involvement of the α7 subunit in survival and development of morphological properties of growing cultured MNs was tested using an antisense strategy. The antisense oligonucleotide significantly decreases the expression of the α7 protein compared with control and mismatch oligonucleotide‐treated cultures. This decrease in the expression of the α7 protein leads to a significant increase in the number of axonal branches and in the length of the axon. The antisense treatment also induces, as early as the first day in culture, a decrease of MN survival, leading to total cell death at day 5. TUNEL staining revealed that the MNs are dying through apoptotic processes. Thus, our study shows that ACh is a morphogenic and trophic factor. These effects are directly linked to the membrane expression level of α7 protein. Indeed, the lower the α7 expression, the lower the inhibition of axonal growth (i.e., axonal elongation) and the lower the MN survival. © 2003 Wiley‐Liss, Inc.
Coenzyme M binds to a [4Fe–4S] cluster in the active site of heterodisulfide reductase as deduced from EPR studies with the [33S]coenzyme M‐treated enzyme
Authors: Duin Evert C. , Bauer Carsten , Jaun Bernhard , Hedderich Reiner
Published: March 2003

Heterodisulfide reductase (Hdr) from methanogenic Archaea catalyzes the reversible reduction of the heterodisulfide (CoM‐S–S‐CoB) of the methanogenic thiol coenzymes, coenzyme M (CoM‐SH) and coenzyme B (CoB‐SH). Upon reaction of the oxidized enzyme with CoM‐SH a unique paramagnetic species is formed, which has been shown to be due to a novel type of [4Fe–4S]3+ cluster. In this work, it was addressed whether CoM‐SH is directly attached to this [4Fe–4S] cluster using CoM‐33SH as substrate and purified Hdr from Methanothermobacter marburgensis and Methanosarcina barkeri. With both enzymes treatment with CoM‐33SH in the presence of duroquinone as an oxidant resulted in a significant broadening of the electron paramagnetic resonance spectrum as compared to CoM‐SH as substrate. The signal broadening resulted from an unresolved anisotropic hyperfine coupling between the 33S nucleus and the paramagnetic center. The results provide compelling evidence for a direct binding of CoM‐SH to the [4Fe–4S] cluster in the active site of the enzyme.
Synthesis of and dyeing characteristics of novel pyrazolo[1,5‐a]pyrimidine derivatives containing two arylazo functions
Authors: Elgemeie G.H. , Helal M.H. , El‐Sayed H.M.
Published: March 2003

Several novel pyrazolo[1,5‐a]pyrimidine derivatives containing two arylazo functions were synthesised from 4‐arylazo‐3,5‐diaminopyrazoles. Such derivatives were used as starting components. The characteristics of and the application properties of the dyes synthesised from 4‐arylazo‐3,5‐diaminopyrazoles were investigated and reported.
Reexamination of the Relation Between Menstrual Cycle and Kampo Diagnosis, Yin-yang
Authors: Mantani Naoki , Kogure Toshiaki , Sakai Shinya , Shimada Yutaka , Tarasawa Katsutoshi
Published: March 2003

Several Chinese herbal medicine textbooks describe that a short menstrual cycle indicates "Yang" status and a long cycle indicates "Yin" status. However, we sometimes encounter Yang patients with a long cycle or Yin patients with a short cycle in daily practice. Therefore, we reviewed the relationship between Yin-Yang and length of menstrual cycle. A questionnaire addressing both menstrual cycle and several parameters for determining Yin-Yang was completed at the time of the patients' visit to the hospital. Patients were divided into Yang or Yin groups, and menstrual cycle was compared between the two groups. A short menstrual cycle was mostly observed in Yin patients (27.42 ± 1.73, 95% CI: 26.32 ~ 28.52, n = 12) and a long cycle was mostly observed in Yang patients (31.63 ± 3.96, 95% C.I: 29.51 ~ 33.74, n = 16). The difference in menstrual cycle between the two groups was significant (p = 0.002), and this result was entirely opposite to the traditional theory. This study identified a discrepancy between the traditional theory and the actual menstrual cycle findings in this small population. Current reexamination of the relationship between Yin-Yang and menstruation in a larger population is warranted.
Isolation and Molecular Structure of 1,1,2,4,5,5-Hexacyano-1,4-pentadienyl Anion. An Unusual Reaction of Tetracyanoethylene with p-Xylene Mediated by a Porphyrinatomanganese(II)
Authors: Sugiura Ken-ichi , Mikami Shinji , Tanaka Takanori , Sawada Masami , Sakata Yoshiteru
Published: March 2003

The reaction of TCNE and meso-tetrakis(4-biphenylyl)porphyrinatomanganese(II) in p-xylene leads to the formation of the 1,1,2,4,5,5-hexacyano-3-(4′-methyphenyl)-1,4-pentadienyl anion, which was characterized by single crystal X-ray diffraction.
Highly Planar Silane [(i-Pr)3Si]3SiH and Silyl Radical [(i-Pr)3Si]3Si·
Authors: Kyushin Soichiro , Sakurai Haruaki , Matsumoto Hideyuki
Published: March 2003

Tris(trialkylsilyl)silane [(i-Pr)3Si]3SiH (1) was synthesized, and the molecule was found to have a nearly planar structure of the polysilane skeleton by X-ray crystallography. Hydrogen abstraction from 1 by tert-butoxyl radical gave the highly stable silyl radical [(i-Pr)3Si]3Si· (2), which also has a planar structure.
Synergistic Effect of PEG-20M and Heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin Mixed Stationary Phase in Gas Chromatography
Authors: Yuan L M , Fu R N , Chen X X , Gui S H , Dai R J
Published: March 2003

In open tubular column gas chromatography, by investigating the chromatographic properties of the mixed stationary phase containing heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin and PEG-20M, as well as comparing with the heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin and the PEG-20M used as individual stationary phase, the synergistic effect was observed on this mixed stationary phase. This separation effects depend on temperature and mixing ratio.
Novel Perfluorocyclohexylation with Bis(perfluorocyclohexane carbonyl) Peroxide
Authors: Sawada Hideo , Kurachi Minaka , Kawase Tokuzo , Takishita Katsuhisa , Tanedani Toshiyuki , Aoshima Kazuyoshi
Published: March 2003

A new bis(perfluorocyclohexane carbonyl) peroxide was prepared by the reaction of the corresponding acyl fluoride and hydrogen peroxide. This peroxide was applicable for the direct introduction of perfluorocyclohexyl group into various organic molecules such as acrylic acid oligomer, benzene and polystyrene; in particular interest, not only equatorial but also axial conformational isomers were isolated in phenylperfluorocyclohexane thus obtained.
A New Approach to Pyrrolophenanthridone Alkaloids via Intramolecular Radical Cyclization
Authors: Tsuge Otohiko , Hatta Taizo , Tsuchiyama Hiroshi
Published: March 2003

A new approach to the synthesis of pyrrolophenanthridone class of alkaloids is described. The method is based on intramolecular radical cyclization of easily accessible 1-aroyl-7-bromoindoles with Bu3SnH and AIBN.
Synthesis of Phosphatidylcholine Having a Very Long Chain Polyunsaturated Fatty Acid
Authors: Haider Syed Shabbir , Tanaka Masatoshi , Alam Md Khorshed , Nakajima Shuhei , Baba Naomichi , Shimizu Sakayu
Published: March 2003

A phosphatidylcholine 9 bearing icosadienoyl and docosahexaenoyl groups at the 1- and 2-positions respectively was synthesized. The synthetic route involves carbon chain elongation of linoleic acid via malonic ester synthesis, preparation of lyso-phosphatidylcholine via lipase-catalyzed mon-acylation of 2-O-methoxyethoxymethylglycerol and phosphodiester synthesis, and finally DCC-mediated esterification.
Unexpected Course of the Intramolecular Darzens Condensation of Dichloroacetoxybenzaldehyde. A Novel One-step Synthesis of 2,2-Dichloro-3-(2-hydroxyphenyl)-3-(2-formylphenoxy) propionic Acid
Authors: Mamedov Vakhid A , Gazizova Lucia Kh , Nurkhametova Ilsiyar Z , Gubaidullin Aidar T , Litvinov Igor A , Tsuboi Sadao , Levin Yakov A
Published: March 2003

The reaction of ortho-di (2) and monochloroacetoxybenzaldehyde (1) withtBuOK and/or NaN(SiMe3)2 under Darzens conden-sation conditions leads to 2,2-dichloro-3-(2-hydroxyphenyl)-3-(2-formylphenoxy) propionic acid (3) and 3-chlorocoumarin (8) depending on number of chlorine atoms in the starting aldehydes (1, 2).
Rhodium-Catalyzed Intramolecular Pauson-Khand Reaction
Authors: Koga Yuji , Kobayashi Toshitake , Narasaka Koichi
Published: March 2003

A rhodium dinuclear carbonyl complex, [RhCl(CO)2]2, serves as a catalyst of the intramolecular Pauson-Khand reaction. 1,6-Enynes are converted to cyclopentenone derivatives in high yield by heating in the presence of the catalyst under an atmospheric pressure of CO.
Retarded Decomposition of the Trimethylammonium Moiety Observed on Photocatalytic Mineralization of Surfactants over TiO2 Photocatalyst
Authors: Fujii Hiroyuki , Sato Hirofumi , Ohtaki Michitaka , Eguchi Koichi , Arai Hiromichi
Published: March 2003

The CO2 evolution rate for photocatalytic mineralization of alkyltrimethylammonium chloride sharply decreased when the mineralization yield became nearly equal to the proportion of the long alkyl carbon to the total organic carbon, suggesting that the photodecomposition rate of the alkyl chains is much faster than that of the trimethylammonium group. Moreover, the presence of Br− significantly suppressed the initial CO2 evolution rate, and resulted in incompleted mineralization with the final mineralization yield virtually equal to the proportion of the carbon atoms not attaching to the quarternary nitrogen.
Photocurrent Generation by Surface Plasmon Excitation via Electron Transfer Quenching of Excited Porphyrins Linked Covalently to a Gold Film Electrode
Authors: Ishida Akito , Sakata Yoshiteru , Majima Tetsuro
Published: March 2003

Photocurrent was generated by surface plasmon excitation upon a porphyrin-modified gold film electrode using p-polarized light at 632.8 nm light in which electron transfer occurred from the excited porphyrin linked covalently to the gold electrode to a quencher such as molecular oxygen and methyl viologen in an aqueous solution.
Synthesis of the First Iron Complexes Containing 1,2-Phenylenedioxysilyl Group
Authors: Yamaguchi Koji , Ueno Keiji , Ogino Hiroshi
Published: March 2003

Reaction of FpSiHCl2 (Fp=(η5-C5H5)Fe(CO)2) with catechol in the presence of NEt3 afforded FpSiH(cat) (2: cat=o-O2C6H4). While the reaction in the presence of 1,3-dimethyl-2-imidazolidinone (DMI) gave FpSiCl(cat) (3). The NMR investigation of the latter reaction revealed that the hydrosilyl complex 2 is formed as an intermediate which is converted into the chlorosilyl complex 3 via H/Cl exchange between 2 and DMI·HCl.
Modeling the Contact Region of Command Layer/Liquid Crystal Molecule by Langmuir-Blodgett Technique
Authors: Ubukata Takashi , Morino Sin-ya , Seki Takahiro , Ichimura Kunihiro
Published: March 2003

A molecularly homogeneous mixed monolayer composed of an azobenzene containing amphiphilic polymer and 4′-pently-4-cyanobiphenyl (5CB) was formed on a water surface. Photoirradiation onto the single LB layer from this mixed monolayer induced reversible orientational changes of 5CB molecule. Preparation of a resonable model of command layer/liquid crystal molecular interface by LB method is proposed.
Synthesis and Photochemical Reactions of Polystannanes.
Authors: Mochida Kunio , Hayakawa Masamichi , Tsuchikawa Takuya , Yokoyama Yasuo , Wakasa Masanobu , Hayashi Hisaharu
Published: March 2003

Several polystannanes were synthesized by the reaction of dichlorostannanes with samarium (II) diiodide and alkali earth metal (Mg, Ca) vapor-solvent cocondensates. Laser flash photolysis of the polystannane involved Sn-Sn bond homolysis to yield mainly polystannyl radicals.
New Oscillatory Phenomena in the Redox Reaction of O2/O2− Couple on a Hanging Mercury Drop Electrode in Acetone Media
Authors: Che Yong , Okajima Takeyoshi , Nakamura Yoshiyuki , Tokuda Koichi , Ohsaka Takeo
Published: March 2003

A new electrochemical oscillation is found in the redox reaction of O2/O2− (superoxide ion) couple on a hanging mercury drop electrode (HMDE) in acetone media. Both electrogeneration of O2− on HMDE and its dissolution (i.e., anodic oxidation) are indispensable for the present oscillation. A probable mechanism is proposed based on related previous studies.
Structural Change of a Cast Film of Amphiphilic Ruthenium(II) Cyano Complex Caused by Electrochemical Oxidation
Authors: Kobayashi Kentaro , Takahashi Shin , Okamoto Kentaro , Yamagishi Akihiko
Published: March 2003

An amphiphilic ruthenium(II) cyano complex, (N(C2H5)4)2[Ru(dc18bpy)(CN)4] (dc18bpy = 4,4′-dioctadecyl-2,2′-bipyridine), was prepared by photo-induced ligand exchange. The X-ray diffraction patterns were compared before and after the electrochemical oxidation of the cast film on an ITO electrode. The film had a layered structure, whose interlayer distance changed irreversibly from 4.60 nm to 4.01 nm when the central Ru(II) ion was oxidized to Ru(III).
Flux Growth of Single Crystals of BaBPO5
Authors: Pan Shilie , Wu Yicheng , Fu Peizhen , Wang Guofu , Zhang Guochun , Li Zhihua , Chen Chuangtian
Published: March 2003

The powder barium borophosphate BaBPO5 was synthesized by solid-state reaction techniques. Single crystals BaBPO5 with sizes up to 20 mm × 15 mm × 10 mm were grown by top-seeded solution growth method using H3BO3–NH4H2PO4 as fluxes. The crystals and the components volatilized were characterized by the method of X-ray powder diffraction.
Synthesis of Vicinal Bis(alkylthio) Derivatives by Reductive Coupling of Dithioacetals Derived from Aromatic Aldehydes with Low Valent Titanium Iodide Species
Authors: Yoshimura Naritoshi , Igarashi Koji , Funasaka Setsuo , Mukaiyama Teruaki
Published: March 2003

Reduction of dithioacetals derived from aromatic aldehydes with low valent titanium iodide species in situ formed by treatment of titanium(IV) iodide with zinc in a mixed solvent of dichloro-methane and pivalonitrile at room temperature afforded coupling products, vicinal bis(alkylthio) derivatives, in good to high yields.
Extensively Interlocked 2-D Supramolecular Architecture of Self-Adhesive Double-Tailed 1,3-Planar-2,4-upright-Calix[4]arene
Authors: Liu Yu , Zhao Bang-Tun , Zhang Heng-Yi , Weng Lin-Hong , Wada Takehiko , Inoue Yoshihisa
Published: March 2003

A novel interlocked 2-D supramolecular architecture is constructed through the synergistic intermolecular interactions of calix[4]arene 1,3-bis(4-nitrobenzoate) in the crystal, which are highly stabilized by the regular π–π and offset stacking, edge-to-face, and/or dipole–dipole interactions.
A Highly Selective HF Sensor Based on A Potassium Ion-Exchanged Waveguide Polarimetric Interferometer
Authors: Qi Zhi-mei , Matsuda Naoki , Itoh Kiminori , Murabayashi Masayuki
Published: March 2003

A simple polarimetric interferometer constructed with a single-mode potassium ion-exchanged (PIE) glass waveguide was used as a disposable HF sensor with an excellent selectivity. By examining the interference between the transverse electric (TE0) and transverse magnetic (TM0) modes during the HF etching of PIE waveguides, the average rate of change in the phase difference was demonstrated to depend linearly on the HF concentration. The compressive stress-induced birefringence in the PIE layer was found to be responsible for the HF-sensing feature of the PIE waveguide polarimetric interferometer.
Water-Soluble Zinc Porphyrins as Receptors for Amino Carboxylates
Authors: Imai Hiroyasu , Misawa Kensuke , Munakata Hiroki , Uemori Yoshio
Published: March 2003

Water-soluble zinc porphyrins bearing an ammonium group and a phenyl or tertiary butyl group above each porphyrin plane were designed and synthesized. Binding data for amino carboxylates in aqueous solution suggested that these porphyrins recognize the carboxylates on the basis of coordinative, Coulomb, and hydrophobic interactions and that a chiral recognition phenomenon for glycyl-tryptophan anion is derived from the cooperation of these interactions.
Ruthenium(II) Complex Having Crown-Ether Moiety at 3,3′-Positions on 2,2′-Bipyridine Ligand: Spectroscopic Responses upon Ion Recognition
Authors: Chiba Masahiro , Ogawa Kazunori , Tsuge Kiyoshi , Abe Masaaki , Kim Haeng-Boo , Sasaki Yoichi , Kitamura Noboru
Published: March 2003

Ru(bpy)2(CE-bpy)2+ was prepared where bpy and CE-bpy were 2,2′-bipyridine and bpy having a crown-ether moiety at the 3,3′ positions, respectively. Although the Ru(II) complex showed only very weak emission in acetonitrile, recognition of Na+ or Li+ by the crown-ether moiety in CE-bpy resulted in an increase in the emission intensity of the complex.
Synthesis of Novel Ruthenium and Rhodium Complexes with a Silsesquioxane-Based Phosphine Ligand
Authors: Wada Kenji , Izuhara Daisuke , Shiotsuki Masashi , Kondo Teruyuki , Mitsudo Take-aki
Published: March 2003

Novel silsesquioxane-containing ruthenium and rhodium complexes were prepared by the reaction of [RuCl2(p-cymene)]2 and [(C2H4)2RhCl]2 with a new silsesquioxane-based tridentate phosphine ligand, (c-C5H9)7Si7O9(OSiMe2CH2CH2PPh2)3 (1).
Aminoisocyanides in Multicomponent Reactions (MCRs): A Facile Synthesis of Substituted 3(5H)-Pyrrolin-2-ones via a Dimroth-type Rearrangement
Authors: Nair Vijay , Mathen Joseph Swaroop , Vinod A Unni , Varma R Luxmi
Published: March 2003

The 1,3-dipolar species generated from diisopropylaminoisocyanide and dimethyl acetylenedicarboxylate (DMAD) is trapped with aldehydes affording substituted 3(5H)-pyrrolin-2-ones presumably via a Dimroth-type rearrangement of the initially formed furanone hydrazones in good yields.
Highly Efficient Dithioacetalization of Carbonyl Compounds Catalyzed with Iodine Supported on Neutral Alumina
Authors: Deka Nabajyoti , Sarma Jadab C
Published: March 2003

Aldehydes and ketones are protected as their corresponding dithioacetals with ethane-1,2-dithiol in the presence of a catalytic amount of iodine supported on neutral alumina surface. This is a high yielding method of carbonyl group protection under mild, neutral and solvent free conditions.
Solvolysis of Optically Active 4-Methylcyclohexylidenemethyl Triflate: Evidence against a Primary Vinyl Cation as an Intermediate
Authors: Fujita Morifumi , Yamamoto Akiyo , Sugimura Takashi , Okuyama Tadashi
Published: March 2003

Solvolysis of (R)-4-methylcyclohexylidenemethyl triflate in aqueous methanol at 140 °C gave stereospecifically (R)-4-methylcycloheptanone to definitively rule out intermediate formation of the achiral primary vinyl cation. The rearrangement must occur via concerted σ-bond participation.
2-(Chloroseleno)benzoyl Chloride: A Tandem Reagent for Selenenylation-Acylation of C-H Acids
Authors: Kloc Krystian , Osajda Mariusz , Mlochowski Jacek
Published: March 2003

The 2-(chloroseleno)benzoyl chloride is a bifunctional electrophile able to react with C-H acids. The selenenylation and acylation of the active methylene group in the presence of triethylamine, lead to the ring closure. Based on this reaction 2-substituted benzo[b]selenophen-3(2H)-ones and 3-hydroxybenzo[b]selenophenes are produced in moderate to high yields.
A Convergent Total Synthesis of the Mucin Related F1α Antigen by One-Pot Sequential Stereoselective Glycosylation
Authors: Mukaiyama Teruaki , Ikegai Kazuhiro , Jona Hideki , Hashihayata Takashi , Takeuchi Kazuya
Published: March 2003

A convergent total synthesis of F1α antigen, a member of the tumor-associated O-linked mucin glycosyl amino acids, was accomplished by one-pot sequential glycosylation. In the first step, the corresponding disaccharide was formed from galactosyl phenylcarbonate 2 or fluoride 3 and thioglycoside 4 by the promotion of TrB(C6F5)4 or TfOH, and following glycosylation of glycosyl amino acid 5 by further addition of N-iodosuccinimide(NIS) afforded protected F1α in 80 or 89% overall yield, respectively. By the subsequent deprotection, F1α antigen was obtained in good yield.
Imprinting of Coordination Geometry in Ultrathin Films via the Surface Sol–Gel Process
Authors: He Junhui , Ichinose Izumi , Kunitake Toyoki
Published: March 2003

Imprinting of Cu2+ and Zn2+ ions was performed in ultrathin TiO2 films by the surface sol–gel process. The imprinted films showed stable and selective binding to template ions over the control metal ion. The selectivity is attributed to the immobilized geometry of ethylenediamine ligand.
Size-Selective Synthesis of CdS Nanoparticles on Polyethylene Films
Authors: Chen Chun-Wei , Higashi Mie , Naito Taichi , Serizawa Takeshi , Akashi Mitsuru
Published: March 2003

Size-selective CdS nanoparticles were synthesized on polyethylene (PE) films with surface-grafted poly(acrylic acid) (PAAc) chains by the stepwise immersion of the films into aqueous solutions of cadmium acetate and sodium sulfide. By varying the surface density of the PAAc chains, the soaking time, and the number of cycles, it was possible to control the degree of coverage of the film and the size of the CdS nanoparticles.
Photochemical Reaction of the Open-Cage Fullerene Derivative with Singlet Oxygen
Authors: Murata Yasujiro , Komatsu Koichi
Published: March 2003

Photochemical reaction of open-cage fullerene 1 with singlet oxygen gave oxidation product 3, which was shown to have an enol and a carbonyl groups on the 12-membered-ring orifice on the fullerene cage by spectroscopic method and density functional calculations.
Migration Behavior of the Polymer Particles Possessing Carboxylate and Borate Moieties in Capillary Electrophoresis
Authors: Tsukagoshi Kazuhiko , Yamaguchi Akinobu , Morihara Nobuo , Nakajima Riichiro , Murata Masaharu , Maeda Mizuo
Published: March 2003

Migration behavior of functional polymer particles, such as carboxylic acid- and phenylboric acid-modified polymer particles, was examined in capillary electrophoresis (CE) using migration buffers containing metal ions or saccharides. It was found that the interaction between functional groups on the particles and the specific chemical species in the migration buffers influenced the migration behavior of the polymer particles. The obtained results supported the possibility that CE becomes useful method for examining the property of functional polymer particles.
Pentavalent organoantimonial derivatives: two simple and efficient synthetic methods for meglumine antimonate
Authors: Demicheli Cynthia , Ochoa Rosemary , Silva Lula Ivana , Gozzo Fabio C. , Eberlin Marcos N. , Frézard Frédéric
Published: March 2003

Two simple and efficient procedures for the preparation of pentavalent antimony derivatives are described, using either antimony pentachloride (SbCl5) or potassium hexahydroxoantimonate (KSb(OH)6) as sources of antimony(V). These two new methods are evaluated for the synthesis of an important anti‐leishmanial drug: meglumine antimonate. Using elemental (carbon, hydrogen, nitrogen) and thermal analysis, atomic absorption (antimony), proton NMR spectroscopy and high‐resolution positive‐ion electrospray ionization mass spectrometry (ESI(+)‐MS), products for the reaction with N‐methyl‐D‐glucamine (NMG) using both the SbCl5 and KSb(OH)6 methods were characterized and found to be similar to a commercial sample of the drug. The only notable difference was observed for the ESI‐MS spectrum of the KSb(OH)6 product; it displays the same pattern of ESI‐generated ions as those of both the SbCl5 product and the commercial drug, but with significantly different abundance ratios. NMR data indicate that the NMG molecules coordinate antimony in two different fashions, which suggests either the coexistence of two different complexes or the existence of a single major complex in which two NMG molecules are coordinated with antimony in an asymmetrical geometry. Copyright © 2003 John Wiley & Sons, Ltd.
Juror decision‐making in a mock sexually violent predator trial: gender differences in the impact of divergent types of expert testimony
Authors: Guy Laura S. , Edens John F.
Published: March 2003

Despite widespread use of mental health testimony in cases where violence risk is at issue, relatively little is known about the impact of such information on juror decision‐making. This study addressed the effects of testimony based on three types of risk assessment instrument or method (clinical opinion, actuarial assessment, and ratings of psychopathy) to examine whether they would have differential impact on jurors' perceptions of the defendant. In a mock sexually violent predator civil commitment trial, 172 undergraduates were presented a case summary that included prosecution and defense expert testimony related to violence risk based on one of the three methods noted above. Consistent with earlier research, the hypothesis that a defendant described as a “high risk psychopath” by the prosecution would be judged more severely than a defendant judged as “high risk” based on other evaluation procedures was supported, but only among female jurors. Unlike prior studies, little support was found for the hypothesis that clinical opinion testimony would be more influential than actuarially based testimony for either gender. Mechanisms that may underlie the observed gender differences are discussed, as are the potential implications of these findings for civil commitment proceedings. Copyright © 2003 John Wiley & Sons, Ltd.
Hydrogenolysis of Cycloalkanes on a Tantalum Hydride Complex Supported on Silica and Insight into the Deactivation Pathway by the Combined Use of 1D Solid‐State NMR and EXAFS Spectroscopies
Authors: Rataboul Franck , Chabanas Mathieu , de Mallmann Aimery , Copéret Christophe , Thivolle‐Cazat Jean , Basset Jean‐Marie
Published: March 2003

Hydrogenolysis of cyclic alkanes is catalysed by [(SiO)2TaH] (1) at 160 °C and leads to lower alkanes and cyclic alkanes including cyclopentane. The turnover number is correlated with the number of carbon atoms of the cyclic alkanes, and therefore while cycloheptane is readily transformed, cyclopentane does not give any product (<1 %). The mechanism of ring contraction probably involves carbene de‐insertion as a key carbon–carbon bond‐cleavage step. The reluctance of cyclopentane to undergo hydrogenolysis was further studied: under the reaction conditions cyclopentane reacts with 1 to give the corresponding cyclopentyl derivative [(SiO)2TaC5H9] (13), which evolves towards cyclopentadienyl derivative [(SiO)2Ta(C5H5)] (14) according to both solid‐state NMR and EXAFS spectroscopies. This latter complex is inactive in the hydrogenolysis of alkanes, and therefore the formation of cyclopentane in the hydrogenolysis of various cyclic alkanes is probably responsible for the de‐activation of the catalyst by formation of cyclopentadienyl complexes.
Niaviolides, New Macrocyclic Sesquiterpenes Secreted by Males of the African Butterfly Amauris niavius
Authors: Stritzke Katja , Schulz Stefan , Boppré Michael
Published: March 2003

The abdominal androconial organs (“hairpencils”) of the African butterfly Amauris niavius (Danainae) emit a complex scent bouquet consisting of previously described aromatic compounds, terpenoids, fatty acids, and hydrocarbons. This work reports the identification of two major sesquiterpenes, each possessing a unique 13‐membered macrolide ring, originating from an α,ψ‐oxidation pattern of the sesquiterpene backbone. To the best of our knowledge, sesquiterpene macrolides have not been found before in nature. The structure elucidation of the two compounds, which we propose to call niaviolide (3) and epoxyniaviolide (4), by NMR and GC/MS experiments is presented, together with their subsequent synthesis. Finally, the absolute configuration of natural 4 was determined to be (S,S) by stereoselective synthesis and chiral gas chromatography. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Effects of alcohol exposure during early life on neuron numbers in the rat hippocampus. I. Hilus neurons and granule cells
Authors: Miki Takanori , Harris Simon J. , Wilce Peter A. , Takeuchi Yoshiki , Bedi Kuldip S.
Published: March 2003

We previously showed that 16‐day‐old rats exposed to a relatively high dose of ethanol at 10‐15 postnatal days of age have fewer neurons in the hilus region of the hippocampus compared with controls. Dentate gyrus granule cell numbers, however, showed no statistically significant changes attributable to the ethanol treatment. It is possible that some of the changes in brain morphology, brought about as a result of the exposure to ethanol during early life, may not be manifested until later in life. This question has been further addressed in an extension to our previous study. Wistar rats were exposed to a relatively high daily dose of ethanol on postnatal days 10–15 by placement in a chamber containing ethanol vapour, for 3 h/day. The blood ethanol concentration was found to be ∼430 mg/dl at the end of the period of exposure. Groups of ethanol‐treated (ET), separation control (SC), and mother‐reared control (MRC) rats were anaesthetised and killed either at 16 or 30 days of age by perfusion with phosphate‐buffered 2.5% glutaraldehyde. The Cavalieri principle and the physical disector methods were used to estimate, respectively, the regional volumes and neuron cell numerical densities in the hilus and granule cell regions of the dentate gyrus. The total numbers of neurons in the hilus region and granule cell layer were computed from these estimates. It was found that 16‐day‐old animals had 398,000–441,000 granule cells, irrespective of group. The numbers of granule cells increased such that by 30 days of age, rats had 487,000–525,500 granule cells. However, there were no significant differences between ethanol‐treated rats and their age‐matched controls in granule cell numbers. In contrast, ethanol‐treated rats had slightly but significantly fewer neurons in the hilus region than did control animals at 16 days of age, but not at 30 days of age. Therefore, it appears that a short period of ethanol exposure during early life can have effects on neuron numbers of some hippocampal neurons, but not others. The effects on hilar neuron numbers, observed as a result of such short periods of ethanol treatment, appeared to be transitory. Hippocampus 2003;13:388–398. © 2003 Wiley‐Liss, Inc.
Subcellular localization of S100A11 (S100C) in LLC‐PK1 renal cells: Calcium‐ and protein kinase c–dependent association of S100A11 with S100B and vimentin intermediate filaments
Authors: Bianchi Roberta , Giambanco Ileana , Arcuri Cataldo , Donato Rosario
Published: March 2003

The subcellular localization of the Ca2+‐modulated protein, S100A11, was investigated in the renal cell line LLC‐PK1 by immunofluorescence and confocal laser scanning microscopy under varying experimental conditions. In control cells, S100A11 was detected on the plasma membrane, where the protein co‐localized with annexin I (ANXA1) at discrete sites, and found diffusely in the cytoplasm. Elevation of the cytosolic Ca2+ concentration by means of the Ca2+ ionophore, ionomycin, caused a significant fraction of S100A11 to associate with vimentin intermediate filament (IF)‐bound S100B, another member of the S100 protein family. Under these conditions, ANXA1 underwent a quite different kind of relocation. Translocation of S100A11 onto vimentin IF‐bound S100B was also observed upon activation of protein kinase C (PKC). Under these conditions, S100A11 appeared to associate directly with vimentin IFs at cell sites displaying low or no abundance of S100B such as cell processes, and, again, S100A11 and ANXA1 underwent a different relocation. Our data suggest the possibility that the intracellular Ca2+ level might regulate the subcellular localization of S100A11 and its interaction with definite target proteins, and that S100A11 might serve the function of modulating S100B activities. Interestingly, in spite of the known ability of S100A11 to form heterotetramers with ANXA1, the two proteins underwent a different relocation on elevation of the cytosolic Ca2+ concentration or activation of PKC, pointing to different regulatory activities of individual proteins in renal cells. Microsc. Res. Tech. 60:639–651, 2003. © 2003 Wiley‐Liss, Inc.
Reactions of gaseous acylium ions with 1,3‐dienes: further evidence for polar [4 + 2+] Diels–Alder cycloaddition
Authors: Lemos Aline B. , Sparrapan Regina , Eberlin Marcos N.
Published: March 2003

A novel reaction of acylium and thioacylium ions, polar [4 + 2+] Diels–Alder cycloaddition with 1,3‐dienes and O‐heterodienes, has been systematically investigated in the gas phase (Eberlin MN, Cooks RG. J. Am. Chem. Soc. 1993; 115: 9226). This polar cycloaddition, yet without precedent in solution, likely forms cyclic 2,5‐dihydropyrylium ions. Here we report the reactions of gaseous acylium ions [(CH3)2N—C+O, Ph—C+O, (CH3)2N—C+S, CH3—C+O, CH3CH2—C+O, and CH2CH—C+O] with several 1‐oxy‐substituted 1,3‐dienes of the general formula RO—CHCH—C(R1)CH2, which were performed to collect further evidence for cycloaddition. In reactions with 1‐methoxy and 1‐(trimethylsilyloxy)‐1,3‐butadiene, adducts are formed to a great extent, but upon collision activation they mainly undergo structurally unspecific retro‐addition dissociation. In reactions with Danishefsky's diene (trans‐1‐methoxy‐3‐(trimethylsilyloxy)‐1,3‐butadiene), adducts are also formed to great extents, but retro‐addition is no longer their major dissociation; the ions dissociate instead mainly to a common fragment, the methoxyacryl cation of m/z 85. This fragment ion is most likely formed with the intermediacy of the acyclic adduct, which isomerizes prior to dissociation by a trimethylsilyl cation shift. Theoretical calculations predict that meta cycloadducts bearing 1‐methoxy and 1‐trimethylsilyloxy substituents are unstable, undergoing barrierless ring opening induced by the charge‐stabilizing effect of the 1‐oxy substituents. In contrast, for the reactions with 1‐acetoxy‐1,3‐butadiene, both the experimental results and theoretical calculations point to the formation of intrinsically stable cycloadducts, but the intact cycloadducts are either not observed or observed in low abundances. Both the isomeric ortho and meta cycloadducts are likely formed, but the nascent ions dissociate to great extents owing to excess internal energy. The ortho cycloadducts dissociate by ketene loss; the meta cycloadducts undergo intramolecular proton transfer to the acetoxy group followed by dissociation by acetic acid loss to yield aromatic pyrylium ions. Either or both of these dissociations, ketene and/or acetic acid loss, dominate over the otherwise favored retro‐Diels–Alder alternative. The pyrylium ion products therefore constitute compelling evidence for polar [4 + 2+] cycloaddition since their formation can only be rationalized with the intermediacy of cyclic adducts. Copyright © 2003 John Wiley & Sons, Ltd.
Introduction
Authors: Ujváry István
Published: March 2003

© 2003 Society of Chemical Industry
Crystal structure of Drosophila angiotensin I‐converting enzyme bound to captopril and lisinopril1
Authors: Kim Ho Min , Shin Dong Ryeol , Yoo Ook Joon , Lee Hayyoung , Lee Jie-Oh
Published: March 2003

Angiotensin I‐converting enzymes (ACEs) are zinc metallopeptidases that cleave carboxy‐terminal dipeptides from short peptide hormones. We have determined the crystal structures of AnCE, a Drosophila homolog of ACE, with and without bound inhibitors to 2.4 Å resolution. AnCE contains a large internal channel encompassing the entire protein molecule. This substrate‐binding channel is composed of two chambers, reminiscent of a peanut shell. The inhibitor and zinc‐binding sites are located in the narrow bottleneck connecting the two chambers. The substrate and inhibitor specificity of AnCE appears to be determined by extensive hydrogen‐bonding networks and ionic interactions in the active site channel. The catalytically important zinc ion is coordinated by the conserved Glu395 and histidine residues from a HExxH motif.
Exact Unemployment Rate Indices
Authors: Greenwood Michael J. , Kohli Ulrich
Published: March 2003

Conventional unemployment rate measures tend to overestimate the degree of labor underutilization if unemployment disproportionately affects less educated and generally less productive workers. Based on index number theory as well as on econometric techniques, this article proposes a number of alternative measures that are exact for specific labor aggregator functions. The results for the United States show that the conventional, unweighted unemployment rate overestimates the true rate by about 0.6 of a percentage point, or by almost 14%.
MARKETS AND INDUSTRY — VENTURE CAPITAL AND ECONOMIC GROWTH: AN INDUSTRY OVERVIEW AND SINGAPORE'S EXPERIENCE
Authors: KOH FRANCIS C. C. , KOH WINSTON T. H.
Published: March 2003

This paper provides an overview of the venture capital industry and its development in Asia and Singapore. Venture capital plays an important role in innovation and economic growth. Indeed, the resurgence of the United States as a technology leader is intimately linked to the success of Silicon Valley. As Singapore enters the next phase of economic development, the creation of internal engines of growth is an urgent task. The Singapore government has done much to provide an environment for entrepreneurship to thrive. Its success at replicating the Silicon Valley culture will be important for Singapore's future economic success.
THE STATE OF ART AND FUTURE DEVELOPMENT OF MORPHOLOGICAL SOFTWARE TOWARDS GENERIC ALGORITHMS
Authors: D'ORNELLAS MARCOS CORDEIRO , VAN DEN BOOMGAARD REIN
Published: March 2003

The goal of this paper is to establish the fundamental requirements of any morphological software in such a way as to produce reliable, precise, and generic algorithm representations in order to overcome the combinatorial explosion of the code needed to deal with all possible kinds of data structures and image types. Algorithms should be built with the guarantee that the desired implementation is written once, process data in an abstract way, and is efficient at the same time. Requirements are derived from a review of some of the most used software packages and image libraries with respect to mathematical morphology including [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text]. Such a review makes it possible to characterize their advantages and drawbacks. These aspects call for software for mathematical morphology that has to be generic and should support a large variety of data types.
THREE-DIMENSIONAL SHAPES OF A FINITE SET OF POINTS
Authors: MELKEMI MAHMOUD
Published: March 2003

The three-dimensional [Formula: see text]-shape is based on a mathematical formalism which determines exact relationships between points and shapes. It reconstructs surface and volume and detects 3D dot patterns for a given point cloud. [Formula: see text]-shape of a set of points is a sub-complex of Delaunay triangulation of this set. It generates a family of shapes according to the selected [Formula: see text] (a set of points). A method to compute the positions of the points of [Formula: see text] is proposed. These points are selected from the vertices of Voronoi diagram by analyzing the form of the polytopes; their elongation. This method allows the [Formula: see text]-shape to reflect different levels of detail in different parts of space. An efficient algorithm computing the three-dimensional [Formula: see text]-shape is presented, the [Formula: see text]-shape of a set of points is derived from the Delaunay triangulation of the same set. The speed of the algorithm is determined by the speed of the algorithm computing the Delaunay triangulation.
MULTIPLE SOLUTIONS OF NONHOMOGENEOUS ELLIPTIC EQUATIONS WITH CRITICAL NONLINEARITY ON SYMMETRIC DOMAINS
Authors: CLAPP MÓNICA , KAVIAN OTARED , RUF BERNHARD
Published: March 2003

We consider the Dirichlet problem associated to the nonhomogenous elliptic equation -Δu = |u|2*-2u + f with critical exponent on a symmetric domain, and study the impact of symmetries on it. We show that a rich symmetry structure will give rise, in some cases, to many solutions.
Expression inXenopusoocytes shows that WT1 binds transcripts in vivo, with a central role for zinc finger one
Authors: Ladomery Michael , Sommerville John , Woolner Sarah , Slight Joan , Hastie Nick
Published: March 2003

The Wilms' tumour suppressor gene WT1 encodes a protein involved in urogenital development and disease. The salient feature of WT1 is the presence of four `Krüppel'-type C2-H2 zinc fingers in the C-terminus. Uniquely to WT1, an evolutionarily conserved alternative splicing event inserts three amino acids (KTS) between the third and fourth zinc fingers, which disrupts DNA binding. The ratio of +KTS:–KTS isoforms is crucial for normal development. Previous work has shown that WT1(+KTS) interacts with splice factors and that WT1 zinc fingers, particularly zinc finger one, bind to RNA in vitro. In this study we investigate the role of zinc finger one and the +KTS splice in vivo by expressing tagged proteins in mammalian cells and Xenopus oocytes. We find that both full-length+/–KTS isoforms and deletion constructs that include zinc finger one co-sediment with ribonucleoprotein particles (RNP) on density gradients. In Xenopus oocytes both isoforms located to the lateral loops of lampbrush chromosomes. Strikingly, only the +KTS isoform was detected in B-snurposomes, but not when co-expressed with –KTS. However,co-expression of the C-terminus (amino acids 233-449, +KTS) resulted in snurposome staining, which is consistent with an in vivo interaction between isoforms via the N-terminus. Expressed WT1 was also detected in the RNA-rich granular component of nucleoli and co-immunoprecipitated with oocyte transcripts. Full-length WT1 was most stably bound to transcripts, followed by the C-terminus; the least stably bound was CTΔF1 (C-terminus minus zinc finger one). Expression of the transcription factor early growth response 1(EGR1), whose three zinc fingers correspond to WT1 zinc fingers 2-4, caused general chromosomal loop retraction and transcriptional shut-down. However, a construct in which WT1 zinc finger one was added to EGR1 mimicked the properties of WT1 (–KTS). We suggest that in evolution, WT1 has acquired the ability to interact with transcripts and splice factors because of the modification of zinc finger one and the +KTS alternative splice.
cAMP-induced AQP2 translocation is associated with RhoA inhibition through RhoA phosphorylation and interaction with RhoGDI
Authors: Tamma Grazia , Klussmann Enno , Procino Giuseppe , Svelto Maria , Rosenthal Walter , Valenti Giovanna
Published: March 2003

We have recently demonstrated that inhibition of Rho GTPase with Clostridium difficile toxin B, or with Clostridium botulinumC3 toxin, causes actin depolymerization and translocation of aquaporin 2(AQP2) in renal CD8 cells in the absence of hormonal stimulation. Here we demonstrate that Rho inhibition is part of the signal transduction cascade activated by vasopressin leading to AQP2 insertion into the apical membrane. Quantitation of active RhoA (GTP-bound) by selective pull down experiments demonstrated that the amount of active RhoA decreased upon stimulation of CD8 cells with the cAMP-elevating agent forskolin. Consistent with this observation, forskolin treatment resulted in a decreased expression of membrane-associated (active) Rho, as assessed by cell fractionation followed by western blotting analysis. In addition, the abundance of the endogenous Rho GDP dissociation inhibitor (Rho-GDI) was found to have decreased in the membrane fraction after forskolin stimulation. Co-immunoprecipitation experiments revealed that, after forskolin stimulation, the amount of Rho-GDI complexed with RhoA increased, suggesting that Rho GTPase inhibition occurs through association of RhoA with Rho-GDI. Finally, forskolin stimulation was associated with an increase in Rho phosphorylation on a serine residue, a protein modification known to stabilize the inactive form of RhoA and to increase its interaction with Rho-GDI. Taken together, these data demonstrate that RhoA inhibition through Rho phosphorylation and interaction with Rho-GDI is a key event for cytoskeletal dynamics controlling cAMP-induced AQP2 translocation.
Construcution of a Complete Bioelectrocatalytic Electrode Composed of Alcohol Dehydrogenase- and All Electron-transfer Components-modified Graphite Felt for Diol Oxidation
Authors: Kashiwagi Yoshitomo , Pan Qinghai , Kurashima Futoshi , Kikuchi Chikara , Anzai Jun-ichi , Osa Tetsuo
Published: March 2003

A poly(acrylic acid)-coated graphite felt electrode immobilizing all bioelectrochemical reaction components of ferrocene, diaphorase, NADH and alcohol dehydrogenase in the domain of the poly(acrylic acid) layer was applied to oxidize electrocatalytically cis-1,2-cyclohexanedimethanol and 3-methyl-1,5-pentanediol to (+)-(1R, 6S)-cis-8-oxabicyclo[4.3.0]nonan-7-one and (3S)-3-methyl-δ-valerolactone, respectively, in a 0.15 M phosphate buffer (pH 8.0) at the constant potential of 0.45 V vs. SCE with high current efficiency (>92%) and high optical purity (>92%).
Hydrogen-Atom Abstraction from the Solvent by the Lowest Excited Triplet State of Chromone Yielding the β-Keto-Type Solvent Adduct(s)
Authors: Nakayama Toshihiro , Torii Yukiyoshi , Shimizu Tadashi , Miki Sadao , Hamanoue Kumao
Published: March 2003

The lowest excited triplet state of chromone with mixed nπ*-ππ* character abstracts a hydrogen atom from the solvent. Although the ketyl-type radical thus generated is indistinguishable from the β-enol-type radical, this radical (or its keto form, i.e., the β-keto-type radical) gives rise to formation of the β-keto-type solvent adduct(s).
Novel Photochromic System Involving Organostannyl Compounds and 2-Aminomethylpyridine
Authors: Kogure Hideo , Hoshida Yuko , Watanabe Ken-ichiro , Kimura Mutsumi , Hanabusa Kenji , Shirai Hirofusa
Published: March 2003

Photochromic behavior of organostannyl complexes was studied. The addition of 2-aminomethylpyridine to Sn(IV)RnX4-n(n=1∼3) resulted in a reddish purple coloration and it showed the character of photochromism.