bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparisons of the M1 genome segments and encoded μ2 proteins of different reovirus isolates
Authors: Yin Peng , Keirstead Natalie D , Broering Teresa J , Arnold Michelle M , Parker John SL , Nibert Max L , Coombs Kevin M
Published: October 2004

Background

The reovirus M1 genome segment encodes the μ2 protein, a structurally minor component of the viral core, which has been identified as a transcriptase cofactor, nucleoside and RNA triphosphatase, and microtubule-binding protein. The μ2 protein is the most poorly understood of the reovirus structural proteins. Genome segment sequences have been reported for 9 of the 10 genome segments for the 3 prototypic reoviruses type 1 Lang (T1L), type 2 Jones (T2J), and type 3 Dearing (T3D), but the M1 genome segment sequences for only T1L and T3D have been previously reported. For this study, we determined the M1 nucleotide and deduced μ2 amino acid sequences for T2J, nine other reovirus field isolates, and various T3D plaque-isolated clones from different laboratories.

Results

Determination of the T2J M1 sequence completes the analysis of all ten genome segments of that prototype. The T2J M1 sequence contained a 1 base pair deletion in the 3' non-translated region, compared to the T1L and T3D M1 sequences. The T2J M1 gene showed ~80% nucleotide homology, and the encoded μ2 protein showed ~71% amino acid identity, with the T1L and T3D M1 and μ2 sequences, respectively, making the T2J M1 gene and μ2 proteins amongst the most divergent of all reovirus genes and proteins. Comparisons of these newly determined M1 and μ2 sequences with newly determined M1 and μ2 sequences from nine additional field isolates and a variety of laboratory T3D clones identified conserved features and/or regions that provide clues about μ2 structure and function.

Conclusions

The findings suggest a model for the domain organization of μ2 and provide further evidence for a role of μ2 in viral RNA synthesis. The new sequences were also used to explore the basis for M1/μ2-determined differences in the morphology of viral factories in infected cells. The findings confirm the key role of Ser/Pro208 as a prevalent determinant of differences in factory morphology among reovirus isolates and trace the divergence of this residue and its associated phenotype among the different laboratory-specific clones of type 3 Dearing.
Alternative splicing of mouse transcription factors affects their DNA-binding domain architecture and is tissue specific
Authors: Taneri Bahar , Snyder Ben , Novoradovsky Alexey , Gaasterland Terry
Published: October 2004

Background

Analyzing proteins in the context of all available genome and transcript sequence data has the potential to reveal functional properties not accessible through protein sequence analysis alone. To analyze the impact of alternative splicing on transcription factor (TF) protein structure, we constructed a comprehensive database of splice variants in the mouse transcriptome, called MouSDB3 containing 461 TF loci.

Results

Our analysis revealed that 62% of these loci in MouSDB3 have variant exons, compared to 29% of all loci. These variant TF loci contain a total of 324 alternative exons, of which 23% are in-frame. When excluded, 80% of in-frame alternative exons alter the domain architecture of the protein as computed by SMART (simple modular architecture research tool). Sixty-eight % of these exons directly affect the coding regions of domains important for TF function. Seventy-five % of the domains affected are DNA-binding domains. Tissue distribution analyses of variant mouse TFs reveal that they have more alternatively spliced forms in 14 of the 18 tissues analyzed when compared to all the loci in MouSDB3. Further, TF isoforms are homogenous within a given single tissue and are heterogeneous across different tissues, indicating their tissue specificity.

Conclusions

Our study provides quantitative evidence that alternative splicing preferentially adds or deletes domains important to the DNA-binding function of the TFs. Analyses described here reveal the presence of tissue-specific alternative splicing throughout the mouse transcriptome. Our findings provide significant biological insights into control of transcription and regulation of tissue-specific gene expression by alternative splicing via creation of tissue-specific TF isoforms.
A genome annotation-driven approach to cloning the human ORFeome
Authors: Collins John E , Wright Charmain L , Edwards Carol A , Davis Matthew P , Grinham James A , Cole Charlotte G , Goward Melanie E , Aguado Begoña , Mallya Meera , Mokrab Younes , Huckle Elizabeth J , Beare David M , Dunham Ian
Published: October 2004

We have developed a systematic approach to generating cDNA clones containing full-length open reading frames (ORFs), exploiting knowledge of gene structure from genomic sequence. Each ORF was amplified by PCR from a pool of primary cDNAs, cloned and confirmed by sequencing. We obtained clones representing 70% of genes on human chromosome 22, whereas searching available cDNA clone collections found at best 48% from a single collection and 60% for all collections combined.
ANCA induces β2 integrin and CXC chemokine-dependent neutrophil-endothelial cell interactions that mimic those of highly cytokine-activated endothelium
Authors: Calderwood Judith W , Williams Julie M , Morgan Matthew D , Nash Gerard B , Savage Caroline O S
Published: October 2004

Antineutrophil cytoplasm antibodies (ANCA) activate neutrophils to undergo a series of coordinated interactions, leading to transendothelial migration, eventually culminating in vascular destruction. The molecular events underlying neutrophil recruitment in ANCA-associated vasculitis need to be defined to enable effective therapeutic manipulation. A flow-based adhesion ssay was used to investigate the role of β2 integrins (CD11a/CD18 and CD11b/CD18) and chemokine receptors [CXC chemokine receptor (CXCR)1 and CXCR2] in neutrophil migration through the endothelium. Two endothelial models were used: a highly activated model stimulated with 100 U/ml tumor necrosis factor α (TNF-α) and a minimally activated model stimulated with 2 U/ml TNF-α and in which ANCA was present as a secondary neutrophil stimulus. CD11a/CD18, CD11b/CD18, and CXCR2 contributed to adhesion and transendothelial migration in both models. However, when the endothelium was minimally activated with TNF-α, CD11b/CD18 played an important role in stabilizing adhesion induced by ANCA immunoglobulin G (IgG). Analysis of β2 integrins and chemokine receptors demonstrated that ANCA IgG had no effect on expression levels at the neutrophil surface but enabled an active conformational change of CD11b/CD18. Similar molecular mechanisms control neutrophil adhesion and migration through highly or minimally TNF-α-activated endothelium. However, the direct ANCA-mediated neutrophil stimulation is needed to drive migration through minimally activated endothelium, and CD11b/CD18 is recruited for greater stability of adhesion during this process and can undergo an activatory, conformational change in response to ANCA IgG.
Transmigrated neutrophils down-regulate the expression of VCAM-1 on endothelial cells and inhibit the adhesion of flowing lymphocytes
Authors: Stone Philip C W , Lally Frank , Rahman Mahbub , Smith Emily , Buckley Christopher D , Nash Gerard B , Rainger G Ed
Published: October 2004

As the first leukocytes recruited during inflmmation, neutrophils are ideally situated to regulate the subsequent recruitment of mononuclear leukocytes. Here, we found that human neutrophils recruited by endothelial cells (EC), which had been stimulated with tumor necrosis factor α for 4 h, inhibited the adhesion of flowing, mixed mononuclear cells or purified lymphocytes over the subsequent 20 h but did not affect the adhesion of a secondary bolus of neutrophils. The degree of inhibition of lymphocyte adhesion increased with the duration of neutrophil-EC contact and with the number of recruited neutrophils. Antibody-blocking studies showed that lymphocyte adhesion was mediated predominantly by vascular cell adhesion molecule-1 (VCAM-1). Recruited neutrophils reduced the EC expression of VCAM-1 but not intercellular adhesion molecule-1 (ICAM-1) or E-selectin in a manner that mirrored the time- and number-dependent reduction in lymphocyte adhesion. VCAM-1 was not shed into the culture supernatant, and a panel of protease inhibitors was unable to reverse its down-regulation, indicating that it was not proteolytically degraded by neutrophils. In EC that had been in contact with neutrophils, the mRNA message for VCAM-1 but not ICAM-1 was down-regulated, indicating that alterations in transcriptional activity were responsible for the reduction in VCAM-1. Thus, under some inflammatory milieu, neutrophils may delay the recruitment of mononuclear leukocytes by regulating the expression of EC adhesion receptors.
CD93 interacts with the PDZ domain-containing adaptor protein GIPC: implications in the modulation of phagocytosis
Authors: Bohlson Suzanne S , Zhang Mingyu , Ortiz Christopher E , Tenner Andrea J
Published: October 2004

CD93 was originally identified as a myeloid cell-surface marker and subsequently associated with an ability to modulate phagocytosis of suboptimally opsonized immunoglobulin G and complement particles in vitro. Recent studies using mice deficient in CD93 have demonstrated that this molecule modulates phagocytosis of apoptotic cells in vivo. To investigate signal transduction mechanisms mediated by CD93, CD93 cytoplasmic tail (CYTO)-binding proteins were identified in a yeast two-hybrid screen. Fifteen of 34 positive clones contained a splice variant or a partial cDNA encoding GIPC, a PSD-95/Dlg/ZO-1 (PDZ) domain-containing protein, shown previously to regulate cytoskeltal dynamics. A single clone of the N-terminal kinase-like protein p105 and an uncharacterized stem cell transcript also showed specificity for binding to the CYTO by yeast two-hybrid. Using the yeast two-hybrid system and an in vitro glutathione S-transferase fusion protein-binding assay, the binding of GIPC to the CYTO was shown to involve a newly identified class I PDZ-binding domain in the CD93 carboxyl terminus. Four positively charged amino acids in the juxtamembrane domain of CD93 were shown to be critical in stabilizing these interactions. Treatment of human monocytes with a cell-permeable peptide encoding the C-terminal 11 amino acids of CD93 resulted in an enhancement of phagocytosis, supporting the hypothesis that this protein-protein interaction domain is involved in the modulation of phagocytosis. These protein interactions may participate as molecular switches in modulating cellular phagocytic activity.
Recombinant HLA-G5 and -G6 drive U937 myelomonocytic cell production of TGF-β1
Authors: McIntire Ramsey H , Morales Pedro J , Petroff Margaret G , Colonna Marco , Hunt Joan S
Published: October 2004

Throughout human pregnancy, activated maternal macrophages producing anti-inflammatory cytokines comprise a stable cell population in the uterus. This organ is also massively infiltrated with semiallogeneic, placenta-derived, invasive cytotrophoblast cells, which produce membrane and soluble isoforms of human leukocyte antigen (HLA)-G. Here, we investigated the possibility that two soluble isoforms of HLA-G, HLA-G5 and -G6, program macrophage production of cytokines. The model system consisted of human U937 myelomonocytic cells treated with phorbol 12-myristate 13-acetate (PMA) and interferon-γ (IFN-γ), which induced differentiation and activation but did not affect their viability or decrease their expression of the two inhibitory immunoglobulin-like transcript (ILT) receptors for HLA-G, ILT2 and ILT4. Exposure of the PMA/IFN-γ-treated U937 cells to increasing concentrations of recombinant HLA-G5 or -G6 (rG5 and rG6) stimulated effects common to the two isoforms. High doses of both significantly decreased interleukin (IL)-10 and dramatically increased transforming growth factor-β1. Differential effectiveness between the isoforms was demonstrated in dose-response studies, as was differential binding to ILT2 and ILT4 in receptor-blocking studies. No effects on production of IL-4, IL-1 receptor antagonist, IL-15, tumor necrosis factor α, IL-1β, or IL-6 were observed. Collectively, the results are consistent with the postulate that environmental programming of decidual macrophages may be dictated in part by their proximity to soluble HLA-G-producing fetal cytotrophoblast cells.
The coordination of signaling during Fc receptor-mediated phagocytosis
Authors: Swanson Joel A , Hoppe Adam D
Published: October 2004

Phagocytosis by macrophages can be initiated by Fcγ receptors (FcR) in membranes that bind to Fc regions of immunoglobulin G (IgG). Activated FcR transduce signals to cytoplasm, which regulate the internalization of IgG-coated particles into plasma membrane-derived vacuoles, phagosomes. Particles internalized by phagocytosis are much larger than FcR, which prompts questions of if and how the receptors are coordinated with each other. FcR-mediated signal transduction entails recruitment of proteins from cytoplasm to the receptor, largely via protein phosphorylation. These FcR signaling complexes then activate proteins that regulate actin, myosin, membrane fusion, and the production of reactive oxygen intermediates. Recent fluorescence microscopic studies of phagocytosis in macrophages indicate that signaling by FcR occurs as a sequence of distinct stages, evident in the spatial and temporal patterns of phosphoinositides, protein kinase C, and Rho-family GTPase activation on forming phagosomes. The coordination of these stages may be regulated by lipids or lipid-anchored proteins, which diffuse away from FcR complexes. Lateral diffusion of FcR-derived signals could integrate FcR-dependent responses over large areas of membrane in the forming phagosome.
CR6-Interacting Factor 1 Interacts with Orphan Nuclear Receptor Nur77 and Inhibits Its Transactivation
Authors: Park Ki Cheol , Song Kwang-Hoon , Chung Hyo Kyun , Kim Ho , Kim Dong Wook , Song Jung Hun , Hwang Eun Suk , Jung Hye Sook , Park Su-Hyeon , Bae Insoo , Lee In Kyu , Choi Hueng-Sik , Shong Minho
Published: October 2004

CR6-interacting factor 1 (CRIF1) was recently identified as a nuclear protein that interacts with the Gadd45 (growth arrest and DNA damage inducible 45) family of proteins and participates in the regulation of the G1/S phase of the cell cycle. However, the nuclear action of CRIF1 is largely unknown. In this study, we demonstrate that CRIF1 acts as a novel coregulator of transactivation of the orphan nuclear receptor Nur77. Both in vitro and in vivo studies show that CRIF1 interacts with Nur77 via the Nur77 AB domain and that it dramatically inhibits the AB domain-mediated transactivation of Nur77. Transient transfection assays demonstrate that CRIF1 inhibits steroid receptor coactivator-2-mediated Nur77 transactivation, and silencing of endogenous CRIF1 by small interfering RNA relieves this repression. CRIF1 possesses intrinsic repressor activities that are not affected by the histone deacetylase inhibitor Trichostatin A. In addition, overexpression of CRIF1 inhibits TSH/protein kinase A-induced Nur-responsive element promoter activity. CRIF1 inhibited Nur77-dependent induction of E2F1 promoter activity, mRNA expression, and Nur77-mediated G1/S progression in cell cycle. These results suggest that CRIF1 acts as a repressor of the orphan nuclear receptor Nur77 by inhibiting AB domain-mediated transcriptional activity.
Targeted Expression of a Dominant-Negative Fibroblast Growth Factor (FGF) Receptor in Gonadotropin-Releasing Hormone (GnRH) Neurons Reduces FGF Responsiveness and the Size of GnRH Neuronal Population
Authors: Tsai Pei-San , Moenter Suzanne M. , Postigo Hector R. , El Majdoubi Mohammed , Pak Toni R. , Gill John C. , Paruthiyil Sreenivasan , Werner Sabine , Weiner Richard I.
Published: October 2004

Increasing evidence suggests that fibroblast growth factors (FGFs) are neurotrophic in GnRH neurons. However, the extent to which FGFs are involved in establishing a functional GnRH system in the whole organism has not been investigated. In this study, transgenic mice with the expression of a dominant-negative FGF receptor mutant (FGFRm) targeted to GnRH neurons were generated to examine the consequence of disrupted FGF signaling on the formation of the GnRH system. To first test the effectiveness of this strategy, GT1 cells, a GnRH neuronal cell line, were stably transfected with FGFRm. The transfected cells showed attenuated neurite outgrowth, diminished FGF-2 responsiveness in a cell survival assay, and blunted activation of the signaling pathway in response to FGF-2. Transgenic mice expressing FGFRm in a GnRH neuron-specific manner exhibited a 30% reduction in GnRH neuron number, but the anatomical distribution of GnRH neurons was unaltered. Although these mice were initially fertile, they displayed several reproductive defects, including delayed puberty, reduced litter size, and early reproductive senescence. Overall, our results are the first to show, at the level of the organism, that FGFs are one of the important components involved in the formation and maintenance of the GnRH system.
Caenorhabditis elegansUBC-2 functions with the anaphase-promoting complex but also has other activities
Authors: Frazier Tyralynn , Shakes Diane , Hota Uma , Boyd Lynn
Published: October 2004

The anaphase-promoting complex or cyclosome (APC/C) is a multi-subunit ubiquitin ligase that regulates the eukaryotic cell cycle. APC/C belongs to the RING finger class of ubiquitin ligases that function by interacting with a ubiquitin-conjugating enzyme (Ubc), thus inciting the Ubc to transfer ubiquitin onto a target protein. Extensive studies with APC/C in other organisms have identified several possible Ubcs that might function as partners for APC/C. This report presents phenotypic and biochemical evidence showing that, in Caenorhabditis elegans, UBC-2 interacts specifically with the APC/C. This conclusion is based on three lines of evidence: first, the RNAi phenotype of ubc-2 is indistinguishable from RNAi phenotypes of APC/C subunits; second, RNAi of ubc-2 but not other Ubcs enhances the phenotype of hypomorphic APC/C mutants; third, purified UBC-2 and APC-11, the RING finger subunit of the APC/C, show robust ubiquitination activity in in vitro assays. APC-11 interaction is specific for UBC-2 as ubiquitination is not seen when APC-11 is combined other C. elegans Ubcs. As expected from the Ubc that functions with the APC/C, ubc-2(RNAi) produces metaphase blocks in both mitotic germ cells and in meiotic divisions of post-fertilization oocytes. In addition, ubc-2(RNAi) results in two germline phenotypes that appear to be unrelated to the APC/C: an expanded transition zone indicative of a pre-pachytene meiotic arrest and endo-reduplicated oocytes indicative of a problem in ovulation or oocyte-soma interactions.
Skeletal muscle satellite cells can spontaneously enter an alternative mesenchymal pathway
Authors: Shefer Gabi , Wleklinski-Lee Monika , Yablonka-Reuveni Zipora
Published: October 2004

We show that muscle satellite cells, traditionally considered as committed myogenic precursors, are comprised of Pax7-expressing progenitors that preserve a mesenchymal repertoire extending beyond a mere myogenic potential. Mouse satellite cells from freshly isolated single myofibers, cultured individually in serum-rich growth medium, produced myogenic and non-myogenic clones. Only the myogenic clones expressed muscle-specific transcription factors and formed myotubes. Pax7 was initially expressed in all clones, but subsequently was associated only with the myogenic clones. Some cells in the non-myogenic clones expressed α-smooth muscle actin and nestin whereas others differentiated into mature adipocytes. This type of cell composition mirrors characteristics of mesenchymal stem cell progeny. Overall, individual myofibers persistently gave rise to both clonal phenotypes, but the ratio of myogenic to non-myogenic clones randomly varied among fibers. This randomness indicates that clonal dichotomy reflects satellite cell suppleness rather than pre-fated cell heterogeneity. We conclude that satellite cells possess mesenchymal plasticity, being able to commit either to myogenesis or to a mesenchymal alternative differentiation (MAD) program.
α4β1- and α6β1-integrins are functional receptors for midkine, a heparin-binding growth factor
Authors: Muramatsu Hisako , Zou Peng , Suzuki Hiromichi , Oda Yoshihiro , Chen Guo-Yun , Sakaguchi Nahoko , Sakuma Sadatoshi , Maeda Nobuaki , Noda Masaharu , Takada Yoshikazu , Muramatsu Takashi
Published: October 2004

Midkine is a heparin-binding growth factor that promotes the growth, survival, migration and differentiation of various target cells. So far, receptor-type protein tyrosine phosphatase ζ, low-density-lipoprotein-receptor-related protein and anaplastic lymphoma kinase have been identified as receptors for midkine. We found β1 integrin in midkine-binding proteins from 13-day-old mouse embryos. β1-Integrin bound to a midkine-agarose column and was eluted mostly with EDTA. Further study revealed that the α-subunits capable of binding to midkine were α4 and α6. Purified α4β1- and α6β1-integrins bound midkine. Anti-α4 antibody inhibited the midkine-dependent migration of osteoblastic cells, and anti-α6 antibody inhibited the midkine-dependent neurite outgrowth of embryonic neurons. After midkine treatment, tyrosine phosphorylation of paxillin, an integrin-associated molecule, was transiently increased in osteoblastic cells. Therefore, we concluded that α4β1- and α6β1-integrins are functional receptors for midkine. We observed that the low-density-lipoprotein-receptor-related-protein-6 ectodomain was immunoprecipitated with α6β1-integrin and α4β1-integrin. The low-density-lipoprotein-receptor-related-protein-6 ectodomain was also immunoprecipitated with receptor-type protein tyrosine phosphatase ζ. α4β1- and α6β1-Integrins are expected to co-operate with other midkine receptors, possibly in a multimolecular complex that contains other midkine receptors.
Novel Cerium(IV) Ammonium Nitrate Mediated Transformation of Styrenes to α-Methoxy Acetophenones
Authors: Nair Vijay , Nair Latha G , Panicker Sreeletha B , Sheeba V , Augustine Anu
Published: October 2004

Styrenes when treated with a methanolic solution of CAN underwent a novel transformation to α-methoxy acetophenones presumably via a radical cation.
Synthesis and Self-Assembly of Rod-Coil Diblock Molecules of Oligophenylenevinylene-Poly(ethylene oxide)
Authors: Xiong Huiming , Qin Lidong , Sun Jingzhi , Zhang Xi , Shen Jiacong
Published: October 2004

A series of amphiphilic rod-coil diblock molecules containing oligophenylenevinylene have been synthesized and demonstrated various aggregate behaviors in selected solvents. They can nano-separate to form either domain structures or stripes in as-cast state.
Structural Analysis of Boron Carbide Using 2D 11B-MQMAS NMR
Authors: Kanehashi Koji , Saito Koji , Sugisawa Hisashi
Published: October 2004

2D 11B-multiple quantum magic angle spinning NMR spectra of boron carbide were measured in order to eliminate the second-order quadrupole interaction of 11B in B4C. Judging from the line width of MQMAS spectrum, not only the second-order quadrupole interaction but also the B-B dipole-dipole interaction was found to cause the line broadening of B4C in 11B-MAS NMR. They affect the line width in the ratio about 1.3 : 1 at spinning rate of 17 kHz.
Thermochromic Properties of Flavylium Salts in Agar-Gel Matrix
Authors: Matsushima Ryoka , Ogiue Atsushi , Fujimoto Shuichi
Published: October 2004

Flavylium salts exhibited a reversible thermochromism in an agar-gel matrix. Thus, by the temperature change from −3 to 50 °C, the absorption band around 600 nm of 7-diethylamino-4′-dimethylaminoflavylium perchlorate increased by a factor of ca. 1.5, while the band around 520 nm substantially decreased. Upon repeated cycles of the color change no significant fatigues were observed. The thermochromic behaviors were tentatively rationalized to the dye aggregation phenomenon enhanced by the sol-gel matrix.
Vibrational Distribution of N2(B3Πg) Produced from Dissociative Recombination of N2O+ in a Helium Flowing Afterglow
Authors: Tsuji Masaharu , Tanoue Takeshi , Tanaka Yuki , Nishimura Yukio
Published: October 2004

N2(B3Πg-A3Σu+) emission resulting from a dissociative recombination (DR) process of N2O+ has been observed in a He afterglow reaction of N2O. The vibrational population of N2(B:v′ = 0-10) exhibited a bimodal distribution with peaks at v′ = 1 and 4, probably associated with the N2(B) + O(1D) and N2(B) + O(3P) processes, respectively.
Molecular Recognition of Organic Ammonium Ions by Diaza-Crown Ether-Modified β-Cyclodextrin in Aqueous Media
Authors: Park Joon Woo , Lee Soo Yeon , Park Kwanghee Koh
Published: October 2004

β-Cyclodextrin (β-CD) functionalized with diaza-18-crown-6 at primary face shows 7-10 fold greater binding constants for aromatic ammonium ions in aqueous media than the unmodified β-CD by the cooperative binding of the aromatic group to β-CD and ammonium group to crown ether moiety.
Dissolution of Chitosan in Dimethyl Sulfoxide by Salt Formation
Authors: Sashiwa Hitoshi , Shigemasa Yoshihiro , Roy René
Published: October 2004

Chitosan dissolved in dimethyl sulfoxide by salt formation with some acids such as p-toluenesulfonic acid (pTsOH), (1R)-(−)-10-camphorsulfonic acid (CSA), methanesulfonic acid, and salicylic acid.
Wacker Oxidation in an Aqueous Phase through the Reverse Phase-Transfer Catalysis of a Self-Assembled Nanocage
Authors: Ito Hirokazu , Kusukawa Takahiro , Fujita Makoto
Published: October 2004

Self-assembled nanocage 1 was found to promote the aerobic, aqueous oxidation of styrene and its derivatives with the aid of (en)Pd(NO3)2. Obviously, the reaction was promoted by a double catalysis system: i.e., cage 1 acted as a reverse phase-transfer catalyst, whereas (en)Pd2+ as an oxidation catalyst.
Synthesis of tBu3E+ Nitrile Complexes by Oxidative Cleavage of tBu3E-EtBu3 (E = Si, Ge, Sn)
Authors: Ichinohe Masaaki , Fukui Hiroshi , Sekiguchi Akira
Published: October 2004

The reaction of hexa-tert-butyldimetallanes (tBu3E-EtBu3; E = Si, Ge, Sn) with trityl tetraarylborates in pivalonitrile or acetonitrile gave tri-tert-butylmetalyl cation nitrile complexes, [tBu3E+(NC-R)], by oxidative E-E bond cleavage. Their structures were determined by spectroscopic methods and X-ray crystallography.
Novel Bimetallic Group 9 Metal Catalysts Containing P,S-Chelating o-Carboranyl Ligand System for the Carbonylation of Methanol
Authors: Lee Heung-Sae , Bae Jin-Young , Ko Jaejung , Kang Yong Soo , Kim Hoon Sik , Kang Sang Ook
Published: October 2004

A series of novel group 9 transition metal complexes containing a P,S-chelating ligand have been prepared. The bimetallic rhodium carbonyl complex is much more effective in catalyzing the carbonylation of methanol to acetic acid than the previously known catalyst, [RhI2(CO)2]−.
Remarkable Enhancement of Catalytic Activity of FSM-16 by Modification with Ammonium Sulfate for Acid-Catalyzed Reactions
Authors: Dapaah John Kwaku Adu , Uemichi Yoshio , Ayame Akimi , Matsuhashi Hiromi , Sugioka Masatoshi
Published: October 2004

Impregnation of FSM-16 with ammonium sulfate followed by optimized thermal pretreatments, especially by evacuation, leads to a remarkable enhancement in the catalytic activity of FSM-16 for acid-catalyzed reactions.
A Novel Carbocationic Species Paired with Tetrakis(pentafluorophenyl)borate Anion in Catalytic Aldol Reaction
Authors: Mukaiyama Teruaki , Yanagisawa Manabu , Iida Daisuke , Hachiya Iwao
Published: October 2004

The aldol reaction of several aldehydes with silyl enol ethers proceeded smoothly to give the corresponding aldols in good to high yields at −78 °C by using 1.0 mol% of a novel cationic species with tetrakis(pentafluorophenyl)borate anion.
Preparation of a New Photodegradable Copolymer LB Film and Its Application to Photopatterning
Authors: Li Tiesheng , Mitsuishi Masaya , Miyashita Tokuji
Published: October 2004

A new type of copolymer LB film containing a photodegradable monomer, tert-butyl 4-vinylphenyl carbonate (tBVPC), was prepared. It was found that the p(DDA/tBVPC) LB film could be efficiently decomposed by deep UV irradiation. After development with an alkali solution a positive-tone pattern could be drawn with a high resolution of 0.75 µm.
Asymmetric Synthesis of the A-ring Part of Ciguatoxin by the Strategy Based on Diastereoselective Hydroboration and Ring Closing Metathesis
Authors: Fujiwara Kenshu , Tanaka Hideki , Murai Akio
Published: October 2004

Asymmetric synthesis of the A-ring part of a marine toxin ciguatoxin (CTX1B) was achieved by the strategy based on ring closing metathesis (RCM), where introduction of the C5 asymmetric center was performed by diastereocontrolled hydroboration of a vinyl ether moiety.
Monolayer Formation of a Hydrophobic Polysilane on Water Surface Assisted by Liquid Crystal Molecule
Authors: Nagano Shusaku , Seki Takahiro , Ichimura Kunihiro
Published: October 2004

A mixed solution of poly(dihexylsilane) and 4′-pentyl-4-cyanobiphenyl (5CB) was spread on pure water. Surface pressure-area isotherm data and Brewster angle microscopy showed that a monomolecular stretching of this hydrophobic polysilane is performed with the assist of 5CB molecule.
Preparation and Structure of Tetrakis(indolo[2,3-b]quinoxalinato)dinickel(II)
Authors: Takekuma Shin-ichi , Katayama Satoshi , Takekuma Hideko
Published: October 2004

Treatment of 6H-indolo[2,3-b]quinoxaline (1) with NaBH4 in ethanol at 82 °C for 10 min under argon gives the reactive anion species 2 (generated by deprotonation of N-6 position of 1), which upon reaction with Ni(Oac)2·4H2O in ethanol at 82 °C for 6 h under argon forms the title dinuclear nickel(II) complex 3. The molecular structure of the novel complex 3, indicating the Ni-Ni distance of 2.618(1) Å, is reported.
Observation of the S2-Emission from 1,4-Anthraquinone
Authors: Itoh Takao , Yamaji Minoru , Shizuka Haruo
Published: October 2004

Emission, excitation, and absorption spectra of 1,4-anthraquinone (1,4-AQ) have been measured in a degassed CCl4 fluid solution at different temperatures. It is shown that 1,4-AQ in CCl4 exhibits weak emission which can be attributed to the S2(π, π*) fluorescence at comparatively high temperature. The S2(π, π*) state is considered to be in thermodynamic equilibrium with the S1(n, π*) state as well as with the T2(n, π*) and T1(π, π*) states. The present observation provides the first example of the S2 emission from the medium-size molecules containing C=O groups.
IVR and Dissociation in the S1 State of Jet-Cooled Benzonitrile-H2O
Authors: Sakota Kenji , Nishi Kaori , Ohashi Kazuhiko , Sekiya Hiroshi
Published: October 2004

The S1 → S0 dispersed fluorescence spectra of jet-cooled benzonitrile-H2O 1:1 complex have been measured by exciting various vibronic levels. The binding energy of the complex has been estimated to be 1187 < D0 < 1644 cm−1. No sign of intramolecular charge transfer has been observed.
Synthesis and Properties of a Novel Tetraazamacrocycle Containing Two Bispidine Units
Authors: Miyahara Yuji , Goto Kenta , Inazu Takahiko
Published: October 2004

A novel cyclam-like macrocyclic tetramine 10 with two bispidine units was synthesized by coupling of bispidine 7 with bispidine bis(α-chloroacetamide) 8, followed by reduction with DIBAL-H. The tetramine 10 revealed very strong basicity and lithium coordinating ability.
A Novel Reaction Mode in the Cycloaddition of Thermally Generated Silylenes with Conjugated Dienes
Authors: Takeda Nobuhiro , Tokitoh Norihiro , Okazaki Renji
Published: October 2004

A thermally generated silylene bearing bulky substituents, Tbt(Mes)Si: (Tbt = 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl; Mes = 2,4,6-trimethylphenyl), reacted with isoprene at room temperature to give the corresponding 2-vinylsilirane, which thermally isomerized to the corresponding 3-silolene, while silylene underwent competitive [1+2] and [1+4] cycloadditions with 2,4-dimethyl-1,3-butadiene.
Remarkable Improvement in Hydrothermal Stability of MCM-41 by Surface Modification with Grignard Reagents
Authors: Yamamoto Katsutoshi , Tatsumi Takashi
Published: October 2004

Grignard reagents were employed for the first time as a surface modifier for a mesoporous silica, MCM-41. Through this modification method, stable Si-C bonds were formed from surface silanol groups via alkoxy species. Thus modified MCM-41 exhibited high hydrophobicity and remarkable hydrothermal stability.
Photocatalytic Decomposition of N2O into N2 and O2 on the Silver(I) Ion-Exchanged ZSM-5 Catalyst
Authors: Matsuoka Masaya , Ju Woo-Sung , Anpo Masakazu
Published: October 2004

Ag+/ZSM-5 catalysts were prepared by an ion-exchange method. UV-irradiation of the Ag+/ZSM-5 catalysts in the presence of N2O led to the photocatalytic decomposition of N2O into N2 and O2 at 298 K. Investigations of the effective wavelength of the irradiated UV-light for the reaction as well as the in-situ characterization of the catalysts by means of UV-Vis, photoluminescence and FT-IR spectroscopies revealed that the photoexcitation of the Ag+-N2O complexes formed between gaseous N2O and the isolated Ag+ ions exchanged within the zeolite cavities play a significant role in the reaction.
Synthesis of Novel Group 4 Metallocene-Containing Silsesquioxanes with a Vinyl Group
Authors: Wada Kenji , Bundo Masaki , Nakabayashi Daisuke , Itayama Naohiko , Kondo Teruyuki , Mitsudo Take-aki
Published: October 2004

Novel zirconocene or hafnocene-containing silsesquioxanes with a vinyl group Cp2M{[(vinyl)Me2Si](c-C5H9)7Si7O12} (Cp = cyclopentadienyl, M = Zr, Hf) were synthesized, as well as a derivative with a trimethylsilyl group Cp2Zr[(Me3Si)(c-C5H9)7Si7O12]. A derivative containing a dimethylethoxysilyl group was also synthesized.
Formation Kinetics and Structure of 3-Octylthiophene Self-Assembled Monolayers on Gold Surfaces
Authors: Noh Jaegeun , Kobayashi Kazutoshi , Lee Haiwon , Hara Masahiko
Published: October 2004

The self-assembly process and the structure of a monolayer of 3-octhylthiophene (OTP) on gold surfaces were monitored and characterized by in situ surface plasmon resonance spectroscopy (SPS) and scanning tunneling microscopy (STM). The formation of well-ordered OTP self-assembled monolayers was confirmed for the first time.
Microwave-Assisted Hydrogenation of Chlorinated Phenols for Complete Dechlorination
Authors: Wada Yuji , Yin Hengbo , Kitamura Takayuki , Yanagida Shozo
Published: October 2004

Microwave-assisted hydrogenation of chlorinated phenols, such as 4-chlorophenol and pentachlorophenol, using platinum supported on activated carbon (Pt/C) as a catalyst, leads to rapid dechlorination, giving chlorine-free chemicals such as phenol, cyclohexanol, and other chlorine-free highly reduced compounds, which provides a facile and complete detoxification method for robust chlorinated aromatics.
Formation of Mosaic Monolayer and Uniformly Mixed Monolayer of the Mixture of Copper(II) and Nickel(II) Complexes Coordinated with Butyl-Substituted Salen
Authors: Miyamura Kazuo , Abe Hiroyuki
Published: October 2004

Two methods have been employed to form different types of monolayers from the mixture of copper(II) and nickel(II) complexes at air-water interface. When the complexes are mixed up before they are put onto the water surface, the π-A isotherm measurement revealed that a uniformly mixed monolayer was formed. On the other hand, when the complexes are dissolved individually and put onto the water surface successively, a mosaic monolayer of the component complexes with independent domains was formed. The domains of the copper(II) complex in the mosaic monolayer could be selectively compressed.
Influence of an Odd-Even Relationship on the Aggregation Modes of “Gemini”-type Cholestrol-Based Gelators and Their Transcription into Silica Gel
Authors: Jung Jong Hwa , Ono Yoshiyuki , Shinkai Seiji
Published: October 2004

Four “gemini”-type cholesterol-based gelators 1n were synthesized. They acted as versatile gelators of organic fluids. The xerogels show lamellar structures for 12 and 14 and fiber structures for 13 and 15 according to the even or odd number of alkyl chains between two nitrogens. The difference in these organogel supramolecular structures has successfully been transcribed into the silica structures by sol-gel polymerization of tetraethoxysilane (TEOS). These results indicate that the novel silica structures can be created by transcription of various superstructures in organogels as a template through the hydrogen-bonding interaction.
Synthesis of BaCO3 Nanowires and Nanorods in the Presence of Different Nonionic W/O Microemulsions
Authors: Zheng Nengwu , Wu Qingsheng , Ding Yaping , Li Yadong
Published: October 2004

Several one-dimensional nanomaterials(wires and rods) of BaCO3 were synthesized in the presence of the nonionic w/o micro-emulsions of Tween-80, Triton X-100 and C12E9. The intermediate and middle course of BaCO3 nanowires formation were captured, and the formation mechanism of the one-dimensional nanomaterials was conjectured as directional aggregation of BaCO3 colloid particles controlled by soft microemulsion template.
Synthesis of Novel Type Resin Based on Calix[4]arene Carboxylate and Selective Separation of Lead from Zinc
Authors: Shinohara Takaaki , Wakisaka Shin-ya , Ohto Keisuke , Inoue Katsutoshi
Published: October 2004

A novel type of resin derived from calix[4]arene carboxylate was synthesized and adsorption behavior for lead(II), zinc(II), copper(II), nickel(II), and cobalt(II) was investigated. Further, column separation of lead(II) from zinc(II) was also carried out. Adsorption equilibria of metal ions showed following order of selectivity series among metal ions: Pb(II) >> Cu(II) > Zn(II) > Co(II) = Ni(II). Separation of lead and zinc using the packed column was sufficiently achieved.
Ion Conductive and Flexible DNA Films
Authors: Ohno Hiroyuki , Takizawa Naomi
Published: October 2004

Ion conductive film was prepared from flexible poly(ethylene oxide) (PEO) and double stranded DNA chains from salmon milt. The ionic conductivity of this DNA/PEO film was greatly improved by the addition of NaClO4. The highest ionic conductivity of 4.2 × 10−4 S cm−1 was observed at 25 °C.
Molecular Assembly of Manganese Fluorinated Mesoporphyrin Monolayer on a Gold Electrode
Authors: Yamada Taku , Kikushima Seiji , Hikita Takami , Nara Akishi , Nishio Etuo , Ohtsuka Toshiaki , Nango Mamoru
Published: October 2004

Disulfide-linked manganese mesoporphyrin derivatives separated by spacer methylene groups (Figure 1) were synthesized and then the porphyrin derivatives were assembled on a gold electrode. Cyclic voltammetry (CV) of the porphyrin monolayer on a gold electrode showed that one set of waves was clearly visible, corresponding to the consecutive monoelectronic reduction of the manganese porphyrin unit, depending upon the spacer methylene groups. Interestingly, a large positive-shift of the redox potential for the mesoporphyrin was observed due to fluorination of the porphyrin ring.
The First Total Synthesis of Natural (−)-Tetracycline
Authors: Tatsuta Kuniaki , Yoshimoto Takuji , Gunji Hiroki , Okado Yoshiya , Takahashi Masaaki
Published: October 2004

Natural (−)-tetracycline has been stereoselectively synthesized from d-glucosamine through [4 + 2] cycloaddition and Michael-Dieckmann type reaction.
De Novo Design of Hemoprotein Model with Peroxidase Activity toward Lipophilic Peroxide
Authors: Tomizaki Kin-ya , Nishino Hidekazu , Kato Tamaki , Miike Akira , Nishino Norikazu
Published: October 2004

A single-chained 49-mer-polypeptide tethering iron(III)-porphyrin folded into a certain conformation with bis-histidine coordination and consumed favorably linoleic acid hydroperoxide rather than H2O2.
A New Cooling-Rate Dependent Thermochromism of Poly(dioctylsilane)
Authors: Kanai Toshinobu , Ishibashi Hiroki , Hayashi Yoshikazu , Ogawa Tatsuo , Furukawa Shoji , West Robert , Dohmaru Takaaki , Oka Kunio
Published: October 2004

A rapidly cooled poly(dioctylsilane) (PDOS) is found to exhibit unprecedented thermochromic behavior showing λmax at 353 nm as the major absorption which is accompanied with a minor one at 375 nm. On heating, the absorption at 353 nm begins to decrease at 250 K and, then, the minor one does at 280 K. Similar temperature dependent behavior is observed in the X-ray powder diffraction around 2θ = 6° which is ascribable to inter-chain alignment. On heating diffraction at 2θ = 6.2° (d = 1.43 nm) disappears firstly, and then that at 6.4° (d = 1. 38 nm) is displaced by the diffraction at 5.8° (d = 1.52 nm).
Suspended Spray Reaction for Preparation of Ru/Al2O3 Catalyst
Authors: Tsuchiya Takeshi , Ichikuni Nobuyuki , Shimazu Shogo , Uematsu Takayoshi
Published: October 2004

Ru/Al2O3 catalysts were prepared by a suspended spray reaction (SSP) method applying a high temperature at 1273 K. The particles of SSP-Ru/Al2O3 were spherical sub-micron composites. The ruthenium species were not sintered but highly dispersed with small crystallite size (< 2 nm) over Al2O3 that retained the original surface area.
An Optically Active Diarylethene Having Cholesterol Units: A Dopant for Photoswitching of Liquid Crystal Phases
Authors: Uchida Kingo , Kawai Yuji , Shimizu Yo , Vill Volkmar , Irie Masahiro
Published: October 2004

A diarylethene1 having cholesterol units was synthesized in an attempt to use it as a dopant to control the phase of liquid crystals. By the addition of the diarylethene, 4-cyano-4′-pentylbiphenyl (K-15)(Tokyo kasei) nematic liquid crystal showed cholesteric liquid crystalline texture. Upon irradiation with UV light, the cholesteric phase was decomposed. The cholesteric phase was recovered by visible light irradiation. The reversible photoinduced-phase change was observed by alternate irradiation with UV and visible light.
Electrochemical Measurement of Dissolved Oxygen from Atmosphere in a Highly Homogeneous Magnetic Field
Authors: Kishioka Shin-ya , Yamada Akifumi , Aogaki Ryoichi , Kiyoshi Tsukasa , Goto Atsushi , Shimizu Tadashi
Published: October 2004

In a very highly homogeneous magnetic field generated by the 270 MHz high resolution NMR magnet system, the accelerated dissolution of atmospheric oxygen into water was confirmed.
Trimerization of a Divalent Silicon Species Bearing the 8-Dimethylamino-1-naphthyl Group Accompanied by the Migration of Methyl and Dimethylamino Groups
Authors: Tamao Kohei , Asahara Masahiro , Toshimitsu Akio
Published: October 2004

A divalent silicon species bearing the 8-(dimethylamino)-1-naphthyl group trimerizes to afford a 1,2-disilaacenaphthene framework incorporated in a trisilane chain and accompanied by the migration of the methyl and dimethylamino groups.
Nucleophilic Addition of a Divalent Silicon Species Bearing the 8-Dimethylamino-1-naphthyl Group to Diphenylacetylenes to Form the 1-Amino-1-silaphenalene Skeleton
Authors: Tamao Kohei , Asahara Masahiro , Saeki Tomoyuki , Feng Shengyu , Kawachi Atsushi , Toshimitsu Akio
Published: October 2004

A 1-amino-1-silaphenalene skeleton is formed by the reaction of a divalent silicon species bearing the 8-(dimethylamino)-1-naphthyl group with diphenylacetylene via an alkenyl anion intermediate.
X-Ray Crystal Structure and Electrochemical Behavior of (5R,5′S)-5,5′-Biguaiazulene-3,3′(5H,5′H)-dione
Authors: Takekuma Shin-ichi , Fukunaga Hideo , Takekuma Hideko , Yamamoto Hiroshi
Published: October 2004

Oxidation of guaiazulene (1) with a 2.5 molar amount of m-chloroperbenzoic acid in ethanol at 0 °C for 1 h under aerobic conditions gives a ca. 2:1:1 mixture of meso and two enantiomeric forms of 5,5′-biguaiazulene-3,3′(5H,5′H)-dione (2), which upon recrystallization from dichloromethane-hexane selectively provides the single crystals of its meso form only. The first X-ray crystallographic analysis and the electrochemical behavior on the title meso form are reported.
Intramolecular [3 + 2]Cycloaddition Reaction of Dipolar Trimethylenemethane
Authors: Nakamura Masaharu , Toganoh Motoki , Wang Xio Qun , Yamago Shigeru , Nakamura Eiichi
Published: October 2004

A variety of alkylidenecyclopropanone acetals possessing a terminal diylophile were allowed to undergo an intramolecular [3 + 2]cycloaddition via a dipolar trimethylenemethane to obtain bicyclo[4.3.0] and [3.3.0] carbo- and heterocycles in good yields. The product selectivities were rigorously controlled by the concerted or stepwise nature of the cycloaddition reaction.
New Synthetic Protocol with Trifluoro-1-propynylamines. An Efficient Access to α-(Trifluoromethyl)-δ-keto Amides via Hetero Diels-Alder Reaction
Authors: Mantani Toshiya , Konno Tsutomu , Ishihara Takashi , Yamanaka Hiroki
Published: October 2004

N,N-Dibutyl(3,3,3-trifluoro-1-propynyl)amine readily reacts with α,β-unsaturated ketones or aldehydes in refluxing benzene for 3–36 h to form the corresponding Diels-Alder adducts, 2-(dibutylamino)-3-(trifluoromethyl)-4H-pyrans, of which the successive treatment with alumina at ambient temperature for 1 h leads to the ring-opening products, α-trifluoromethylated δ-keto amides in fairly good to excellent yields.
Preparation and Photoelectrochemical Properties of a Self-Assembled Monolayer of a Ruthenium Tris(2,2′-bipyridine)-viologen 1:2 Linked Compound
Authors: Terasaki Nao , Akiyama Tsuyoshi , Yamada Sunao
Published: October 2004

A ruthenium tris(2,2′-bipyridine)-viologen 1:2 linked disulfide was prepared. A gold electrode modified with this compound showed a higher efficiency of photocurrent as compared with a corresponding 1:1 linked compound.
Preparation of UV-dye TMQ-Doped Silica Film and Xerogel by Sol-gel Method
Authors: Dong Wenting , Zhu Congshan
Published: October 2004

UV dye TMQ-doped silica film and slab were prepared by sol-gel process with dioxane as cosolvent of the initial solutions. The maxima TMQ concentrations in the initial solutions for the transparent silica film and slab are 1.24 × 10−2 M and 1.5 × 10−3 M respectively. Luminescence quenching was not observed when TMQ concentration for the film is less than 6.2 × 10−3 M. Obvious red shift of absorption and emission maxima was observed, comparing with those of TMQ-cyclohexane solution.
A Route to Functionalized (η3-Allyl)dicarbonylnitrosyliron Complexes: Regio- and Stereoselective Acylmetallation of Allenes
Authors: Itoh Keiji , Nakanishi Saburo , Takata Toshikazu
Published: October 2004

Allenes regio- and stereoselectively react with alkyl halides in the presence of tetrabutylammonium tricarbonylnitrosyl ferrate to give anti-(η3-2-acylallyl)dicarbonylnitrosyliron complexes in good yields. The reaction provides a convenient method for preparation of di- and trisubstituted η3-allyl iron complexes with acyl groups at the central carbon of the allylic ligands.
Selective Synthesis of Methylal from Methanol on a New Crystalline SbRe2O6 Catalyst
Authors: Yuan Youzhu , Liu Haichao , Imoto Hideo , Shido Takafumi , Iwasawa Yasuhiro
Published: October 2004

A novel SbRe2O6 catalyst was active for the selective methanol oxidation to methylal (CH2(OCH3)2). Other known Sb-Re oxides, Sb4Re2O13 and SbOReO4·2H2O produced almost no methylal. The bulk and surface of the SbRe2O6 catalyst was characterized by XRD, Raman, XPS and SEM. The high performance of SbRe2O6 may be attributed to the Re-oxide octahedra connecting with Sb-O chains.
Photocurrent Generation by the Self-Assembled Monolayers Integrating a Photoenergy-Harvesting System and an Electron-Transport System of Helical Peptide
Authors: Morita Tomoyuki , Kimura Shunsaku , Kobayashi Shiro , Imanishi Yukio
Published: October 2004

A self-assembled monolayer (SAM) composed of a dialkyl compound carrying an N-ethylcarbazolyl (Ecz) group and a helical peptide carrying an anthryl (Ant) group was prepared on gold. The photocurrent magnitude of the bicomponent SAM in the presence of an electron acceptor was larger than that of the unicomponent SAMs. The efficient photocurrent generation of the bicomponent SAM is due to the integration of the photoenergy-harvesting and electron-transport systems.