bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interleukin‐13 receptor α2 chain
Authors: Kioi Mitomu , Kawakami Mariko , Shimamura Takeshi , Husain Syed R. , Puri Raj K. 
Published: August 2006

AbstractBACKGROUNDEpithelial ovarian cancer demonstrates high mortality due to diagnosis at an advanced stage. In the search for a biomarker for early diagnosis and a target for therapy, the issue of whether interleukin‐13 receptor (IL‐13R), shown to be expressed on a variety of human cancers, is expressed in ovarian tumor samples was explored. In addition, whether this receptor serves as a biomarker and can be targeted by IL‐13 cytotoxin was examined.METHODSIL‐13R expression in 15 normal and 68 ovarian tumor tissue samples was determined by immunohistochemistry. Correlation between clinicopathologic features and IL‐13R expression was analyzed. The efficacy of IL‐13R‐directed cytotoxin was determined in mice with subcutaneous, orthotopic, and peritoneal metastatic ovarian cancer.RESULTSImmunohistochemical analyses revealed that 83% of ovarian cancer specimens express IL‐13Rα2, a high‐affinity IL‐13R subunit chain, whereas normal ovary samples expressed none or very low levels. The majority of clear cell ovarian carcinomas with the worst prognosis showed strong staining for IL‐13Rα2. IL‐13 cytotoxin was highly cytotoxic to the IGROV‐1 ovarian cancer cell line in vitro, and it mediated significant antitumor activity against a xenografted tumor model. The antitumor effects were confirmed by treating orthotopically implanted or peritoneal metastatic ovarian tumors, which showed significant extension of survival in immunodeficient mice. IL‐13 cytotoxin also prevented cachexia in treated mice. The soluble form of IL‐13Rα2 was detected in the serum of mice with peritoneal metastasis, and the level decreased to baseline in the treated group.CONCLUSIONSIL‐13Rα2 is a promising target for ovarian cancer therapy, and the soluble form of IL‐13R may be a possible surrogate marker for disease monitoring. Cancer. Published 2006 by the American Cancer Society.
A Photophysical Study of Terphenyl Core Oligosulfonimide Dendrimers Exhibiting High Steady‐State Anisotropy
Authors: Bergamini Giacomo , Ceroni Paola , Balzani Vincenzo , Del Mar Villavieja Maria , Kandre Ramchandra , Zhun Igor , Lukin Oleg 
Published: August 2006

AbstractThe photophysical properties of three dendrimers containing a p‐terphenyl core with appended sulfonimide branches of different size and n‐octyl chains have been investigated in dichloromethane solution. In the dendrimer absorption spectra contributions from both the branches and the core are clearly identified. The fluorescence spectra show only the characteristic fluorescence of the terphenyl unit. Energy transfer from the appended chromophoric groups to the core does not occur. In the dendrimers, the terphenyl core exhibits a very high fluorescence quantum yield (ca. 0.75) and a short emission lifetime (0.8 ns). These properties allowed investigations of the fluorescence depolarization caused by rotation of the dendrimers. The dendrimers show a very high steady‐state anisotropy in dichloromethane solution at room temperature (0.24 for the largest one), compared to that of the parent terphenyl under the same experimental conditions (<0.01) and in rigid matrix (0.33). Both the n‐octyl chains and the sulfonimide branches play important roles to slow down the molecular rotation.
New Polynuclear Mo–Fe Complexes with Ferrocenylamidobenzimidazole Ligands
Authors: Martinho Paulo N. , Quintal Susana , Costa Paulo J. , Losi Serena , Félix Vitor , Gimeno M. Concepción , Laguna Antonio , Drew Michael G. B. , Zanello Piero , Calhorda Maria José 
Published: August 2006

AbstractThe reaction between [Mo(η3‐C3H5)(CO)2(NCMe)2Br] (1) and the ferrocenylamidobenzimidazole ligands FcCO(NH2benzim) (L1) and (FcCO)2(NHbenzim) (L2) led to a binuclear (2) and a trinuclear (3) Mo–Fe complex, respectively. The single‐crystal X‐ray structure of [Mo(η3‐C3H5)(CO)2(L2)Br] [L2 = {[(η5‐C5H5)Fe(η5‐C5H4CO)]2(2‐NH‐benzimidazolyl)}] shows that L2 is coordinated to the endo Mo(η3‐C3H5)(CO)2 group in a κ2‐N,O‐bidentate chelating fashion whereas the MoII centre displays a pseudooctahedral environment with Br occupying an equatorial position. Complex 2 was formulated as [Mo(η3‐C3H5)(CO)2(L1)Br] on the basis of a combination of spectroscopic data, elemental analysis, conductivity and DFT calculations. L1 acts as a κ2‐N,N‐bidentate ligand. In both L1 and L2, the HOMOs are mainly localised on iron while the C=O bond(s) contribute to the LUMO(s) and the next highest energy orbitals are Fe–allyl antibonding orbitals. When the ligands bind to Mo(η3‐C3H5)(CO)2Br, the greatest difference is that Mo becomes the strongest contributor to the HOMO. Electrochemical studies show that, in complex 2, no electronic interaction exists between the two ferrocenyl ligands and that the first electron has been removed from the MoII‐centred HOMO. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Assembly and Upconversion Properties of Lanthanide Coordination Polymers Based on Hexanuclear Building Blocks with (μ3‐OH) Bridges
Authors: Weng Danfeng , Zheng Xiangjun , Jin Linpei 
Published: August 2006

AbstractThree novel hexanuclear core‐based hydroxidolanthanide coordination polymers [Ln3(BDC)3.5(OH)2(H2O)2]·H2O [Ln = Y (1), Yb (2) and Er (3); BDC = 1,4‐benzenedicarboxylate] were prepared by the hydrothermal method. The controlled hydrolysis of lanthanide ions led to an open hexanuclear cluster core. The hexanuclear core containing six (μ3‐OH) bridged LnIII ions from two asymmetric units adopts a chair‐like configuration. It behaves as a building block and is linked by the BDC ligands to form a 3D framework. The guest water molecules occupy the 1D channels in the structure. The upconversion spectra of the Y:Er‐Yb codoped coordination polymers have been studied. The distinct upconversion emissions come from two‐photon or three‐photonexcitation of Y:Er‐Yb codoped coordination polymers andarise from ErIII transitions of the type 4F5/2→4I15/2,2H11/2→4I15/2, 4S3/2→4I15/2 and 4F9/2→4I15/2. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis and Reactivity of the RuIII Complexes [RuTp(PR3)Cl2] — Precursors for RuTp Dihydrogen Complexes
Authors: Pavlik Sonja , Puchberger Michael , Mereiter Kurt , Kirchner Karl 
Published: August 2006

AbstractThe air‐sensitive DMF‐containing intermediate [RuTp(PR3)(Cl)(DMF)] is formed by refluxing a DMF solution of [RuTp(COD)Cl] (1) in the presence of at least 1 equiv. of PR3 (PR3 = PPh3, PPh2iPr, PiPr3, and PCy3). On exposure to air in the presence of CCl4, this complex is readily converted into the respective RuIII complexes [RuTp(PR3)Cl2] (2a–d). These compounds are air‐stable, readily accessible, permit easy variations as far as the electronic and steric properties of the PR3 co‐ligands are concerned, and are reducible to a variety of RuIITp complexes. Treatment of 2 with NaBH4 affords dihydrogen compounds of the type [RuTp(PR3)(H)(η2‐H2)]. Reduction of 2 can also be accomplished with Zn in the presence of CH3CN and pyridine, which affords the diamagnetic RuII compounds [RuTp(PR3)(CH3CN)2]+ (4a–c) and [RuTp(PR3)(py)Cl] (5). X‐ray structures of representative complexes are presented. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Pressure‐Induced Metal–Semiconductor–Metal Transitions in an MMX‐Chain Complex, Pt2(C2H5CS2)4I
Authors: Kobayashi Atsushi , Tokunaga Aya , Ikeda Ryuichi , Sagayama Hajime , Wakabayashi Yusuke , Sawa Hiroshi , Hedo Masato , Uwatoko Yoshiya , Kitagawa Hiroshi 
Published: August 2006

AbstractThe electrical conductivity and X‐ray diffraction measurements were performed for a highlyconductive halogen‐bridged binuclear‐metal mixed‐valence complex (the so‐called MMX chain), Pt2(C2H5CS2)4I, under high pressure up to 2.5 GPa. The complex exhibited pressure‐induced metal–semiconductor–metal transitions at 0.5 and 2.1 GPa. The X‐ray diffuse scatterings were observed at k = n + 0.5 (n: integer) under ambient pressure, which are derived from the charge‐density wave (CDW: ···Pt2+–Pt2+···I–Pt3+–Pt3+–I···) fluctuation in the MMX chain. Above 0.5 GPa, where the pressure‐induced metal–semiconductor transition occurred, these scatterings disappeared. The electronic phases under high pressure (P) were found to be attributable to the metallic averaged‐valence state (AV: –Pt2.5+–Pt2.5+–I–Pt2.5+–Pt2.5+–I–) with CDW fluctuation of P < 0.5 GPa, semiconducting charge‐polarization state (CP: ···Pt2+–Pt3+–I···Pt2+–Pt3+–I···) of 0.5 < P < 2.1 GPa, and metallic AV state of P > 2.1 GPa. The electronic state of Pt2(C2H5CS2)4I is very sensitive to pressure, which implies that the phase competition among the CP, CDW, and AV phases is present in the MMX chain. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Chiral C2‐Boron‐Bis(oxazolines) in Asymmetric Catalysis – A Theoretical Study of the Catalyzed Enantioselective Reduction of Ketones Promoted by Catecholborane
Authors: Bandini Marco , Bottoni Andrea , Cozzi Pier Giorgio , Miscione Gian Pietro , Monari Magda , Pierciaccante Rossana , Umani‐Ronchi Achille 
Published: August 2006

AbstractC2‐Symmetrical boron complexes, prepared by the reactions of 2,2′‐methylenebis(oxazolines) (BOXs) with catecholborane (CATBH), can be used as catalysts (5–10 mol‐%) in the enantioselective reduction of prochiral ketones (ee 72–86 %), giving the desired alcohols in satisfactory yields. We have theoretically investigated the mechanism of the reduction of chloroacetophenone at the DFT level and the computational results have provided a complete mechanistic picture, which explains the stereochemical outcome of the reaction. The B–BOXate complex binds both the reducing agent CATBH and the carbonyl compound, activating the former as a hydride donor and enhancing the electrophilicity of the latter. Moreover, the structure of two boron–BOX (BOXate) complexes has been confirmed by means of X‐ray diffraction techniques.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Gold‐Catalyzed Cycloisomerization of α‐Aminoallenes to 3‐Pyrrolines –Optimization and Mechanistic Studies
Authors: Morita Nobuyoshi , Krause Norbert 
Published: August 2006

AbstractThe gold‐catalyzed cycloisomerization of various α‐aminoallenes affords the corresponding 3‐pyrrolines in good to high chemical yields and – if the amino group is unprotected – with complete axis‐to‐center chirality transfer. Diminished levels of chirality transfer were observed in cases of N‐protected substrates, which may be the result of partial epimerization of the allene in the presence of the gold precatalyst. The low reactivity of the intramolecular hydroamination of unprotected α‐aminoallenes with AuCl3 was improved by use of gold(I) halides as the precatalyst. Mechanistic studies suggest that a gold(I) compound (formed by oxidation of the aminoallene) is the catalytically active species even if the reaction is started with a gold(III) precatalyst. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Asymmetric Hydrogenation of Pyridines: Enantioselective Synthesis of Nipecotic Acid Derivatives
Authors: Lei Aiwen , Chen Mao , He Minsheng , Zhang Xumu 
Published: August 2006

AbstractAn asymmetric hydrogenation process of 3‐substituted pyridine derivatives has been developed with the use of a Rh‐TangPhos complex as the catalyst. The whole process consists of an efficient partial hydrogenation of nicotinate and a subsequent highly enantioselective, Rh‐catalyzed, homogeneous hydrogenation. A series of chiral nipecotic acid derivatives have been synthesized. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Field studies on factors affecting very fine and ultra fine particulate organic matter deposition in low‐gradient sand‐bed streams
Authors: Hünken Andreas , Mutz Michael 
Published: August 2006

AbstractThe knowledge on particle deposition in streams is mainly based on investigations in mountain streams. No data exist from low‐gradient sand‐bed streams that largely differ in the morphological and hydraulic factors proposed to affect deposition. To identify physical control on particle deposition in low‐gradient streams, we assessed deposition of very fine and ultra fine organic particulate matter in 18 sand‐bed stream reaches. We added particles derived from lake sediment and assessed the mean transport distance SP and the deposition velocity vdep. Additionally, reach hydraulics were estimated by injections of a conservative solute tracer (NaCl). Among the low‐gradient streams, particle deposition kinetics were variable but similar to deposition in mountain streams. SP was solely related to the flow velocity. This relation was confirmed when comprising published data on deposition of fine organic particles. An association between particle deposition and transient storage factors was insignificant. We found significance of the transient storage to SP only for repeated measures within a single reach, when flow velocity and benthic conditions were nearly constant. Measured vdep/vfall ratios were much larger than unity in most reaches. Evidence from this relation suggests that the vertical transport of very fine and ultra fine organic particulate matter through the water column was caused mainly by vertical mixing. Copyright © 2006 John Wiley & Sons, Ltd.
A mouse strain difference in tumorigenesis induced by biodegradable polymers
Authors: Ahmed Saifuddin , Tsuchiya Toshie 
Published: August 2006

AbstractThe use of poly‐L‐lactic acid (PLLA) surgical implants for repair of bone fractures has gained popularity in the past decade. The aim of this study was to evaluate the in vivo effect of PLLA plates on subcutaneous tissue in two mouse strains, BALB/cJ and SJL/J, which have higher and lower tumorigenicity, respectively. Gap‐junctional intercellular communication and protein expression of connexin 43 were significantly suppressed, whereas secretion of transforming growth factor‐β1 and expression of extracellular matrix, insulin‐like growth factor binding protein 3, and cysteine‐rich intestinal protein 2 were significantly increased in PLLA‐implanted BALB/cJ mice when compared with BALB/cJ controls. Finally, tumors were formed after implantation of cultured cells from the more‐tumorigenic BALB/cJ, but not SJL/J, mice into nude mice. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Neurosteroids and the songbird model system
Authors: Schlinger Barney A. , London Sarah E. 
Published: August 2006

AbstractThe brain is now widely recognized as having the capacity to make steroids, neurosteroidogenesis. Although many functions are known for steroids that might be made in the brain, the evolution of and natural biological functions for these neurosteroids are not fully understood. In songbirds, neurosteroids may function in the development of neural circuits controlling song and may also participate in the activation of some steroid‐dependent behaviors during the non‐breeding season. In addition to neuroanatomical and behavioral evidence, we have physiological, molecular, and biochemical evidence for the expression and activity of steroidogenic enzymes in the brains of developing and adult songbirds. We review the evidence published so far for songbird neurosteroidogenesis and discuss why we believe songbird species are excellent models for the study of brain steroid synthesis and action. J. Exp. Zool. 305A:743–748, 2006. © 2006 Wiley‐Liss, Inc.
Mode of action and functional significance of avian gonadotropin‐inhibitory hormone (GnIH): a review
Authors: Tsutsui Kazuyoshi , Ubuka Takayoshi , Yin Hong , Osugi Tomohiro , Ukena Kazuyoshi , Bentley George E. , Ciccone Nick , Inoue Kazuhiko , Chowdhury Vishwajit S. , Sharp Peter J. , Wingfield John C. 
Published: August 2006

AbstractNeuropeptide control of gonadotropin secretion at the level of the anterior pituitary gland is primarily through the stimulatory action of the hypothalamic decapeptide, gonadotropin‐releasing hormone (GnRH). However, a hypothalamic neuropeptide acting at the level of the pituitary to negatively regulate gonadotropin secretion has, until recently, remained unknown in any vertebrate. In 2000, we discovered a novel hypothalamic neuropeptide inhibiting gonadotropin release at the level of the pituitary in quail and termed it gonadotropin‐inhibitory hormone (GnIH). A gonadotropin‐inhibitory system is an intriguing concept and provides us with an unprecedented opportunity to study the regulation of avian reproduction from an entirely novel standpoint. To elucidate the mode of action of GnIH, we further identified the receptor for GnIH and characterized its expression and binding activity in quail. The identified GnIH receptor possessed seven transmembrane domains and specifically bound to GnIH in a concentration‐dependent manner. The expression of GnIH receptor was found in the pituitary and several brain regions including the hypothalamus. These results suggest that GnIH acts directly on the pituitary via GnIH receptor to inhibit gonadotropin release. GnIH may also act on the hypothalamus to inhibit GnRH release. To understand the functional significance of GnIH in avian reproduction, we also investigated the mechanism that regulates GnIH expression. Interestingly, melatonin induced dose‐dependently GnIH expression and melatonin receptor (Mel1c) was expressed in GnIH neurons. Thus melatonin appears to act directly on GnIH neurons via its receptor to induce GnIH expression. Based on these studies, GnIH is likely an important neuropeptide for the regulation of avian reproduction. J. Exp. Zool. 305A:801–806, 2006. © 2006 Wiley‐Liss, Inc.
Comparative genomics in vertebrate evolution and development
Authors: Amemiya Chris T. , Gomez‐Chiarri Marta 
Published: August 2006

AbstractThe vast quantities of publicly available DNA sequencing data and genome resources are enabling biologists to investigate age‐old problems in biology that were not addressable previously. In this review, we discuss how comparative genomics is practiced and how the data can be used to make biological inferences with respect to vertebrate evolution and development. Examples are taken from the well‐known HOX clusters, which are always a high‐priority target for genomic analyses due to their inferred role in the evolution of metazoans. In addition, we briefly discuss the application of genomic approaches to problems in comparative endocrinology.J. Exp. Zool. 305A:672–682, 2006. © 2006 Wiley‐Liss, Inc.
Major contributions of comparative endocrinology to the development and exploitation of the incretin concept
Authors: Conlon J. Michael , Patterson Steven , Flatt Peter R. 
Published: August 2006

AbstractAn incretin is a factor released by the gut in response to nutrients that facilitates uptake of glucose by peripheral tissues. The incretin concept predates the discovery of insulin but it is now clear that incretins act by stimulating secretion of this hormone. As glucagon has insulin‐releasing activity, it was speculated that intestinal glucagon‐like immunoreactivity (enteroglucagon) was involved in the incretin effect but it was an achievement in the field of comparative endocrinology that led to the demonstration that the preproglucagon gene encodes the most potent incretin in the human. Characterization of cloned cDNAs encoding two preproglucagons from the Brockmann body of the anglerfish Lophius americanus demonstrated that the glucagon sequence is flanked by a 34 amino‐acid‐residue sequence with appreciable structural similarity to glucagon that was termed glucagon‐like peptide (GLP). A 36 amino‐acid‐residue ortholog of anglerfish GLP was subsequently identified in human preproglucagon but this peptide had only weak insulin‐releasing activity. However, alignment of GLP sequences from human and teleost fish showed that the human ortholog is extended from its N‐terminus by a hexapeptide. Removal of this extension by an endogenous protease generates GLP‐1‐(7–36)amide, the potent and effective form of the incretin. More recently, comparative endocrinology has contributed to the exploitation of incretins as antidiabetic drugs. Exendin‐4, a GLP‐1 receptor agonist first isolated from the venom of the Gila monster Heloderma suspectum, is a clinically valuable, long‐acting incretin and the skins of several species of frogs synthesize potent insulin‐releasing peptides with therapeutic potential. J. Exp. Zool. 305A:781–786, 2006. © 2006 Wiley‐Liss, Inc.
Unexpected diversity of aryl hydrocarbon receptors in non‐mammalian vertebrates: insights from comparative genomics
Authors: Hahn Mark E. , Karchner Sibel I. , Evans Brad R. , Franks Diana G. , Merson Rebeka R. , Lapseritis Joy M. 
Published: August 2006

AbstractLigand‐activated receptors are well‐known targets of environmental chemicals that disrupt endocrine signaling. Genomic approaches are providing new opportunities to understand the comparative biology and molecular evolution of these receptors. One example of this is the aryl hydrocarbon receptor (AHR), a basic‐helix–loop–helix (bHLH)‐Per–Arnt–Sim (PAS) transcription factor through which planar aromatic hydrocarbons cause altered gene expression and toxicity. In contrast to humans and other mammals, which possess a single AHR, teleosts such as the Atlantic killifish (Fundulus heteroclitus) have at least two AHRs (AHR1 and AHR2). Analysis of sequenced genomes has revealed additional, unexpected AHR diversity in non‐mammalian vertebrates, including the chicken Gallus gallus (three predicted AHR genes), bony fishes such as the pufferfish Takifugu (formerly Fugu) rubripes (five AHR genes) and zebrafish Danio rerio (three AHR genes), and cartilaginous fishes such as the spiny dogfish Squalus acanthias (three AHR genes). In contrast, invertebrates appear to possess single AHRs that do not bind typical ligands of vertebrate AHRs. We suggest that AHR diversity in vertebrates arose through both gene and whole‐genome duplications combined with lineage‐specific gene loss, and that sensitivity to the developmental toxicity of planar aromatic hydrocarbons may have had its origin in the evolution of the ligand‐binding capacity of the AHR in the chordate lineage. Comparative molecular and genomic studies are providing new insights into AHR diversity and function in non‐mammalian species, revealing additional complexity in mechanisms by which environmental chemicals interfere with receptor‐dependent signaling. J. Exp. Zool. 305A:693–706, 2006. © 2006 Wiley‐Liss, Inc.