bluuebunny/crossref_metadata_2025 huggingface dataset:
Enantioselective Alkylation of Aldehydes Catalyzed by a Highly Active Titanium Complex of 3‐Substituted Unsymmetric BINOL.
Authors: Harada Toshiro , Kanda Kousou
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Enantioselective Catalytic Intramolecular Cyclopropanation Using Modified Cinchona Alkaloid Organocatalysts.
Authors: Johansson Carin C. C. , Bremeyer Nadine , Ley Steven V. , Owen Dafydd R. , Smith Stephen C. , Gaunt Matthew J.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
trans‐Hydroalumination/Alkylation: One‐Pot Synthesis of Trisubstituted Allylic Alcohols.
Authors: Langille Neil F. , Jamison Timothy F.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Chlorochalcogenation of Acetylenes with Benzenesulfen(or selenen)amides and Tin(IV) Chloride.
Authors: Martynov A. V. , Makhaeva N. A. , Amosova S. V.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Diphenyl Carbonate from CO2, Phenoxide, and CCl4 with ZnCl2 as Catalyst.
Authors: Li Zhenhuan , Qin Zhangfeng , Zhu Huaqing , Wang Jianguo
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Regioselective Synthesis of Pentasubstituted Benzene Derivatives: TBAF as an Effective Catalyst for the Sequential Michael Addition‐Intramolecular Aldolization.
Authors: Park Da Yeon , Gowrisankar Saravanan , Kim Jae Nyoung
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Diastereoselective and Concise Synthesis of Functionalized Vinyl Epoxides with a Morita—Baylis—Hillman Backbone.
Authors: Davoust Marion , Briere Jean‐Francois , Metzner Patrick
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Novel Aziridination of Olefins: Direct Synthesis from Sulfonamides Using t‐BuOI.
Authors: Minakata Satoshi , Morino Yoshinobu , Oderaotoshi Yoji , Komatsu Mitsuo
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Highly Efficient Three‐Component Synthesis of β‐Lactams (IV)/(V) from N‐Methylhydroxylamine, Aldehydes, and Phenylacetylene.
Authors: Zhao Liang , Li Chao‐Jun
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Dithiaethyneazuliporphyrin — A Contracted Heterocarbaporphyrin.
Authors: Berlicka Anna , Sprutta Natasza , Latos‐Grazynski Lechoslaw
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Convenient Synthesis of 4‐Alkyl‐5‐aminoisoxazoles.
Authors: Bourbeau Matthew P. , Rider James T.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Discovery of 4‐Substituted‐8‐(2‐hydroxy‐2‐phenyl‐cyclohexyl)‐2,8‐diaza‐spiro [4.5]decan‐1‐one as a Novel Class of Highly Selective GlyT1 Inhibitors with Improved Metabolic Stability.
Authors: Alberati Daniela , Hainzl Dominik , Jolidon Synese , Krafft Eva A. , Kurt Anke , Maier Axel , Pinard Emmanuel , Thomas Andew W. , Zimmerli Daniel
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Unexpected Epimerization at C2 in the Horner—Wadsworth—Emmons Reaction of Chiral 2‐Substituted‐4‐oxopiperidines (II).
Authors: Etayo Pablo , Badorrey Ramon , Diaz‐de‐Villegas Maria D. , Galvez Jose A.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Discovery of Potent CRTh2 (DP2) Receptor Antagonists.
Authors: Birkinshaw Timothy N. , et al. et al.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
An Efficient One‐Pot Synthesis of 5‐Aryl Substituted 2‐Amino‐5,8‐dihydropyrido[2,3‐d]pyrimidin‐4,7‐diones under Microwave Irradiation Without Catalyst.
Authors: Tu Shujiang , Wang Qian , Xu Jianing , Zhu Xiaotong , Zhang Jinpeng , Jiang Bo , Jia Runhong , Zhang Yan , Zhang Junyong
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis and Evaluation of Thiazepines as Interleukin‐1β Converting Enzyme (ICE) Inhibitors.
Authors: Ellis Christopher D. , et al. et al.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Ullmann Coupling Reaction: A New Approach to Tetraarylstannanes.
Authors: Shaikh Nadim S. , Parkin Sean , Lehmler Hans‐Joachim
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Chlorins Linked with Pyrazoline by 1,3‐Dipolar Diazomethane Cycloaddition Reaction.
Authors: Wang Jin‐Jun , Li Jia‐Zhu , Gryko Daniel , Shim Young Key
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Largamides A—H, Unusual Cyclic Peptides from the Marine Cyanobacterium Oscillatoria sp.
Authors: Plaza Alberto , Bewley Carole A.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Stereoselective Synthesis of Highly O‐Functionalized Enantiopure 2,3,4‐Trisubstituted Tetrahydrofurans by Tandem Debenzylative Cyclization of Glycal Derived 2,3‐Epoxy Alcohols.
Authors: Reddy L. Vijaya Raghava , Roy Abhijeet Deb , Roy Raja , Shaw Arun K.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Pongamone A—E, Five Flavonoids from the Stems of a Mangrove Plant, Pongamia pinnata.
Authors: Li Liya , Li Xiang , Shi Cui , Deng Zhiwei , Fu Hongzheng , Proksch Peter , Lin Wenhan
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Apoptolidin A: Total Synthesis and Partially Glycosylated Analogues.
Authors: Wehlan Hermut , Dauber Mario , Mujica Fernaud M. Teresa , Schuppan Julia , Keiper Sonja , Mahrwald Rainer , Juarez Garcia M.‐Elisa , Koert Ulrich
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Toward the Total Synthesis of Spirastrellolide A. Part 1. Strategic Considerations and Preparation of the Southern Domain (I).
Authors: Fuerstner Alois , Fenster Michael D. B. , Fasching Bernhard , Godbout Cedrickx , Radkowski Karin
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Toward the Total Synthesis of Spirastrellolide A. Part 2. Conquest of the Northern Hemisphere (I).
Authors: Fuerstner Alois , Fenster Michael D. B. , Fasching Bernhard , Godbout Cedrickx , Radkowski Karin
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structure—Activity Relationships of N‐Substituted Piperazine Amine Reuptake Inhibitors.
Authors: Fray M. Jonathan , Bish Gerwyn , Fish Pual V. , Stobie Alan , Wakenhut Florian , Whitlock Gavin A.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Metallic Single‐Crystal CoSi Nanowires via Chemical Vapor Deposition of Single‐Source Precursor.
Authors: Schmitt Andrew L. , Zhu Lei , Schmeisser Dieter , Himpsel F. J. , Jin Song
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Nanomaterials under High‐Pressure
Authors: San‐Miguel Alfonso
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Transition Metal Complexes of Tethered Arenes
Authors: Adams Joanne R. , Bennett Martin A.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Fluorinated Benzazoles and Benzazines
Authors: Nosova E. V. , Mochul'skaya N. N. , Kotovskaya S. K. , Lipunova G. N. , Charushin V. N.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Recent Advances in Thionating Reagents for the Synthesis of Organosulfur Compounds
Authors: Polshettiwar Vivek , Kaushik M. P.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
S‐Adenosyl‐L‐methionine: Beyond the Universal Methyl Group Donor
Authors: Roje Sanja
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
[18]Annulene: To Be or Not to Be Planar
Authors: Morreale Antonio
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
General and Theoretical Aspects of the Peroxide Group
Authors: Bach Robert D.
Published: November 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Macrocyclic Aminopyrimidines as Multitarget CDK and VEGF‐R Inhibitors with Potent Antiproliferative Activities
Authors: Lücking Ulrich , Siemeister Gerhard , Schäfer Martina , Briem Hans , Krüger Martin , Lienau Philip , Jautelat Rolf
Published: November 2006

X‐ray structures from CDK2–aminopyrimidine inhibitor complexes led to the idea to stabilize the active conformation of aminopyrimidine inhibitors by incorporating the recognition site into a macrocyclic framework. A modular synthesis approach that relies on a new late‐stage macrocyclization protocol that enables fast and efficient synthesis of macrocyclic aminopyrimidines was developed. A set of structurally diverse derivatives was prepared. Macrocyclic aminopyrimidines were shown to be multitarget inhibitors of CDK1/2 and VEGF‐RTKs. In addition, potent antiproliferative activities toward various human tumor cells and a human tumor xenograft model were demonstrated.
Experience with heat shock protein‐peptide complex 96 vaccine therapy in patients with indolent non‐Hodgkin lymphoma
Authors: Oki Yasuhiro , McLaughlin Peter , Fayad Luis E. , Pro Barbara , Mansfield Paul F. , Clayman Gary L. , Medeiros L. Jeffrey , Kwak Larry W. , Srivastava Pramod K. , Younes Anas
Published: November 2006

BACKGROUND.

The objective of this phase II trial was to investigate the safety and efficacy of autologous heat shock protein‐peptide complex 96 (HSPPC‐96) vaccines prepared from tumor specimens of patients with newly diagnosed or previously treated indolent non‐Hodgkin lymphoma (NHL).

METHODS.

The study was for patients with indolent B‐cell NHL with measurable lesions. HSPPC‐96 vaccines were prepared from patients' resected tumor specimens and administered as a 25‐μg intradermal injection in the absence of disease progression every week for 4 weeks and then every 2 weeks until the vaccine supply was exhausted.

RESULTS.

Twenty patients were enrolled in this trial. The median patient age was 59 years. Ten patients had been treated previously (median, 2 regimens; range, 1 to 7). Eighteen (90%) patients had stage III or IV disease. Autologous vaccines were successfully prepared for 17 (85%) patients and all received at least 1 dose. The treatment was very well tolerated. One patient experienced a response with biopsy‐proven clearance of the lymphoma cells in 2 of the skin nodules at 3.0 months that lasted for 7.0 months. Eight patients had stable disease for 6.0 to 19.8 months. The median failure‐free survival duration in patients who received vaccine therapy was 5.2 months.

CONCLUSIONS.

HSPPC‐96 can be prepared from tumor specimens for the majority of lymphoma patients, but it had limited efficacy in inducing responses in patients with active diseases. Further studies of HSPPCs, therefore, should be considered in adjuvant settings or in combination with other immunomodulatory agents to assess survival benefit. Cancer 2007. © 2006 American Cancer Society.
A Comparison of Methods to Compute the Potential of Mean Force
Authors: Trzesniak Daniel , Kunz Anna‐Pitschna E. , van Gunsteren Wilfred F.
Published: November 2006

Most processes occurring in a system are determined by the relative free energy between two or more states because the free energy is a measure of the probability of finding the system in a given state. When the two states of interest are connected by a pathway, usually called reaction coordinate, along which the free‐energy profile is determined, this profile or potential of mean force (PMF) will also yield the relative free energy of the two states. Twelve different methods to compute a PMF are reviewed and compared, with regard to their precision, for a system consisting of a pair of methane molecules in aqueous solution. We analyze all combinations of the type of sampling (unbiased, umbrella‐biased or constraint‐biased), how to compute free energies (from density of states or force averaging) and the type of coordinate system (internal or Cartesian) used for the PMF degree of freedom. The method of choice is constraint‐bias simulation combined with force averaging for either an internal or a Cartesian PMF degree of freedom.
Nucleolar localization of phosphatidylinositol 4‐kinase PI4K230 in various mammalian cells
Authors: Kakuk Annamária , Friedländer Elza , Vereb György , Kása Anita , Balla András , Balla Tamás , Heilmeyer Ludwig M. G. , Gergely Pál , Vereb György
Published: November 2006

Background:

Previous immunohistochemical investigations could not detect PI4K230, an isoform of mammalian phosphatidylinositol 4‐kinases (also called type III α), in the nucleus and nucleolus of cells in spite of its predicted nuclear localization signals.

Methods:

Immunofluorescent detection of PI4K230 and other PI4K isoforms was performed on formaldehyde (PFA) or ethanol fixed cells and rat brain cryosections. Costaining with nucleolin and the effect of siRNA, Triton X‐100, DNase, and RNase treatments were also tested to determine the localization of PI4K230.

Results:

PI4K230 gives a prominent signal in the nucleolus of ethanol fixed rat brain cryosections and of several cell types in addition to its presence in the nucleus and cytoplasm. The PI4K230 immunoreactivity of the nucleolus is masked in PFA fixed cells, but it can be restored by treatment of PFA fixed cells with hot wet citrate buffer or by washing the cryosections with PBS prior to PFA fixation. Nucleolar PI4K230 occurs in a Triton X‐100 resistant complex. Treatment of COS‐7 cells with siRNA targeting PI4K230 and permeabilized B50 cells with DNase or RNase results in the loss of PI4K230 signal from the nucleolus.

Conclusion:

These experiments suggest the participation of PI4K230 in a DNase and RNase sensitive complex with a unique localization and function in the nucleolus. © 2006 International Society for Analytical Cytology
“Virtual flow cytometry” of immunostained lymphocytes on microscopic tissue slides: iHCFlow™ tissue cytometry
Authors: Cualing Hernani D. , Zhong Eric , Moscinski Lynn
Published: November 2006

Background:

A method and approach is developed for fully automated measurements of immunostained lymphocytes in tissue sections by means of digital color microscopy and patent pending advanced cell analysis. The validation data for population statistic measurements of immunostained lymphocytes in tissue sections using tissue cytometry (TC) is presented. The report is the first to describe the conversion of immunohistochemistry (IHC) data to a flow cytometry‐like two parameter dot‐plot display, hence the technique is also a virtual flow cytometry. We believe this approach is a paradigm shift, as well as novel, and called the system iHCFlow™ TC. Seven issues related to technical obstacles to virtual flow cytometry (FC) are identified.

Design:

Segmentation of a 512 × 474 RGB image and tabular display of statistical results table took 12–15 s using proprietary developed algorithms. We used a panel of seven antibodies for validation on 14 cases of mantle cell lymphoma giving percentage positive, total lymphocytes, and staining density. A total of 2,027 image frames with 810,800 cell objects (COBs) were evaluated. Antibodies to CD3, CD4, CD8, Bcl‐1, Ki‐67, CD20, CD5 were subjected to virtual FC on tissue. The results of TC were compared with manual counts of expert observers and with the results of flow cytometric immunophenotyping of the same specimen.

Results:

The correlation coefficient and 95% confidence interval by linear regression analysis yielded a high concordance between manual human results (M), FC results, and TC results per antibody, (r = 0.9365 M vs. TC, r= 0.9537 FC vs. TC). The technical issues were resolved and the solutions and results were evaluated and presented.

Conclusion:

These results suggest the new technology of TC by iHCFlow™ could be a clinically valid surrogate for both M and FC analysis when only tissue IHC is available for diagnosis and prognosis. The application for cancer diagnosis, monitoring, and prognosis is for objective, rapid, automated counting of immunostained cells in tissues with percentage results. We report a new paradigm in TC that converts IHC staining of lymphocytes to automated results and a flow cytometry‐like report. The dot plot histogram display is familiar, intuitive, informative, and provides the pathologists with an automated tool to rapidly characterize the staining and size distribution of the immunoreactive as well as the negative cell population in the tissue. This systems tool is a major improvement over existing ones and satisfy fully the criteria to perform Cytomics (Ecker and Tarnok, Cytometry A 2005;65:1; Ecker and Steiner, Cytometry A 2004;59:182–190; Ecker et al., Cytometry A 2004;59:172–181). © 2006 International Society for Analytical Cytology
Temporal and spatial expression profiles of the Fat3 protein, a giant cadherin molecule, during mouse development
Authors: Nagae Shigenori , Tanoue Takuji , Takeichi Masatoshi
Published: November 2006

Cadherins constitute a superfamily of cell–cell interaction molecules that participate in morphogenetic processes of animal development. Fat cadherins are the largest members of this superfamily, with 34 extracellular cadherin repeats. Classic Fat, identified in Drosophila, is known to regulate cell proliferation and planar cell polarity. Although 4 subtypes of Fat cadherin, Fat1, Fat2, Fat3, and Fat4/Fat‐J, have been identified in vertebrates, their protein localization remains largely unknown. Here we describe the mRNA and protein distributions of Fat3 during mouse development. We found that Fat3 expression was restricted to the nervous system. In the brain, Fat3 was expressed in a variety of regions and axon fascicles. However, its strongest expression was observed in the olfactory bulb and retina. Detailed analysis of Fat3 in the developing olfactory bulb revealed that Fat3 mRNA was mainly expressed by mitral cells and that its proteins were densely localized along the dendrites of these cells as well as in their axons to some extent. Fat3 transcripts in the retina were expressed by amacrine and ganglion cells, and its proteins were concentrated in the inner plexiform layer throughout development. Based on these observations, we suggest that Fat3 plays a role in the interactions between neurites derived from specific subsets of neurons during development. Developmental Dynamics 236:534–543, 2007. © 2006 Wiley‐Liss, Inc.
Reactivity and X‐ray Structural Studies in Ligand Substitution of [Cp/(Ind)Ru(dppf)Cl] – Epimerisation in [Cp/(Ind)Ru(Josiphos)Cl] {Cp = η5‐C5H5, Ind = η5‐C7H9, dppf = 1,1′‐Bis(diphenylphosphanyl)ferrocene, Josiphos = (R)‐(–)‐1‐[(S)‐2‐(Diphenylphosphanyl)ferrocenyl]ethyldicyclohexylphosphane}
Authors: Ng Sin Yee , Fang Guihua , Leong Weng Kee , Goh Lai Yoong , Garland Marc V.
Published: November 2006

Ligand substitution of [(Ind)Ru(PPh3)2Cl] (1) led to the isolation of [(Ind)Ru(PPh3){Ph2P(CH2)2C9H7}Cl] (2), [(Ind)Ru(dppf)Cl] (3) and [(Ind)Ru{(Ph2PCH2)3CMe}]PF6 ([4]PF6), and diastereoisomers [(R)‐ and (S)‐(Ind)Ru(Josiphos)Cl] [(R)‐5 and (S)‐5], where (R)‐(S)‐Josiphos is the ferrocene‐based chiral diphosphane ligand (R)‐(–)‐1‐[(S)‐2‐(diphenylphosphanyl)ferrocenyl] ethyldicyclohexylphosphane. The Cp analogues of 5, viz. (R)‐6 and (S)‐6, were also obtained from [CpRu(PPh3)2Cl] (1a). Josiphos‐dependent epimerisation was observed, with conversion of the (S) isomer to the (R) isomer in both cases. Chloride abstraction of 3 with NaPF6 in CH3CN and NaN3 in EtOH gave [(Ind)Ru(dppf)(CH3CN)]PF6 ([7]PF6) and [(Ind)Ru(dppf)(N3)] (8), respectively. The azido ligand in 8 underwent [3+2] dipolar cycloaddition with dimethyl acetylenedicarboxylate to give a N‐bound bis(methoxycarbonyl)‐1,2,3‐triazolato complex, 9. X‐ray crystal structures of the new complexes, except (R)‐5, (S)‐5 and (S)‐6, have been determined. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Two‐ and Three‐Dimensional Coordination Polymers From the Reaction of Bis‐ and Tris(2‐aminoethyl)amine with Titanium and Zirconium Alkoxides
Authors: Fric Helmut , Puchberger Michael , Schubert Ulrich
Published: November 2006

The reaction of bis(2‐aminoethyl)amine with M(OiPr)4 (M = Ti, Zr) affords the chain‐like coordination polymers [M2(OiPr)8(H2NCH2CH2NHCH2CH2NH2)]∞, where only the NH2 groups of the amine are coordinated to the M2(OiPr)8 units. 2D NMR spectroscopy shows that the adducts dissociate into the starting compounds when dissolved in CD2Cl2 but are slowly re‐formed in solution over a period of two weeks. Puckered layers of condensed six‐membered rings of [Ti2(OiPr)8]3[N(CH2CH2NH2)3]2 are formed when [Ti(OiPr)4] is treated with tris(2‐aminoethyl)amine. The voids in the center of the rings are filled by non‐coordinated Ti2(OiPr)8 guest molecules. In contrast, chains of [Zr2(OiPr)8(H2NCH2CH2NR′CH2CH2NH2)] {R′ = CH2CH2NH2[Zr2(OiPr)8(HOiPr)]} are formed upon treatment of tris(2‐aminoethyl)amine with [Zr(OiPr)4].(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Two Novel Reactions of a Ruthenium‐Coordinated Phenazine – Oxidative Aromatic Ring Hydroxylation and Dimerization via a New C–N Bond Formation
Authors: Banerjee Priyabrata , Mostafa Golam , Castiñeiras Alfonso , Goswami Sreebrata
Published: November 2006

The reaction of [Ru(CH3OH)2(N∧N)2]2+ [N∧N = 2,2′‐bipyridine (bpy) and 1,10‐ortho‐phenanthroline(phen)] with the phenazine ligand, [HL1 = 6‐p‐anisyl‐2‐(p‐anisylamino)‐3(4H)‐p‐anisylimine‐9‐methoxyphenazine] in the presence of a base (NEt3) afforded two mononuclear ruthenium complexes, [Ru(L1)(N∧N)2]X (2), and [Ru(LO)(N∧N)2]X2 (3), [LO = 7‐methoxy‐5‐(4‐methoxyphenyl)‐2,3‐bis(4‐methoxyphenylimino)‐3,5‐dihydro‐2H‐phenazin‐1‐one] together with a diruthenium complex [(N∧N)2RuL2Ru(N∧N)2]X3 (4), [L2 = 7,8′‐dimethoxy‐5,10′‐bis(4‐methoxyphenyl)‐2,3′‐bis(4‐methoxyphenylamino)‐3,2′‐bis(4′‐methoxyphenylimino)‐3,5,2′,10′‐tetrahydro‐[1,5′]biphenazinyl‐5′‐ylium], (X = ClO4– or CF3SO3–). The complexes 3 and 4 were also obtained from the pure complex 2 under two different experimental conditions. Oxidative aromatic ring hydroxylation of the complex 2 produced 3 while the diruthenium complex, 4, was formed by dimerization of 2 via a new C–N bond formation. The products were thoroughly characterized with the help of 1H NMR and ESI‐MS spectral measurements. Final authentication of the two complexes of the transformed phenazine ligands viz. 3 and 4 were made by single‐crystal X‐ray structure determination of the two representative complexes. These compounds are intensely colored and show transitions in the visible region, which are ascribed as metal‐to‐ligand charge transfer (MLCT). Notably, intensities of the two MLCT of the compound 4 are significantly higher than those of 2 and 3. Redox properties of the complexes are reported. Electrochemical oxidation of compound 2, even in the presence of trace moisture, produced compound 3. Cyclic voltammetry of compound 3 shows a reductive response near–0.35 V. Its one‐electron reduced product is blue and shows an intense EPR signal at g = 2.001. The voltammogram of the diruthenium complex 4 consists of two responses near 0.70 and 0.85 V. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
A New Biomimetic‐Like Aromatization of the Cyclic End Groups of Terpenoids with Stereospecific Migration of One of the Methyl Groups: A Convenient Route to Isorenieratene (ϕ,ϕ‐Carotene)
Authors: Valla Alain , Andriamialisoa Zo , Valla Benoist , Labia Roger , Le Guillou Régis , Dufossé Laurent , Cartier Dominique
Published: November 2006

The synthesis of isorenieratene, a natural carotenoid isolated from the marine sponge Reniera japonica and from some anoxygenic phototrophic bacteria or nonphotosynthetic actinomycetes, was performed from α‐, β‐ and retro‐ionones. In this series of cyclohexenes, this synthesis is the first to include a one‐pot aromatization of the cyclic end group with concomitant regioselective migration of one methyl group from the gem dimethyl functionality. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Highly Enantioselective Cyanoformylation of Aldehydes Catalyzed by a Mononuclear Salen‐Ti(OiPr)4 Complex Produced In Situ
Authors: Chen Shi‐Kui , Peng Dan , Zhou Hui , Wang Li‐Wei , Chen Fu‐Xue , Feng Xiao‐Ming
Published: November 2006

An efficient enantioselective cyanoformylation of aldehydes with ethyl cyanoformate, catalyzed by a salen‐Ti(OiPr)4 complex generated in situ, has been developed. Studies of nonlinear effects indicated that the mononuclear salen‐titanium complex, and not a heterochiral complex, played a key role in the stereodiscriminating step of the reaction. During the preparation of the catalyst, the addition of isopropyl alcohol was shown to avoid the formation of a heterochiral complex. In the presence of 5 mol‐% catalyst, the reaction can be carried out in excellent yields (up to 99 %) and with high enantioselectivities (up to 91 % ee). From preliminary studies, a transition state to explain the origin of the asymmetric induction has been proposed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Diastereospecific Tandem Prins Cyclisation/Rearrangement Reactions for the Desymmetrisation of Cyclohexa‐1,4‐dienes
Authors: Elliott Mark C. , El Sayed Nahed N. E. , Paine James S.
Published: November 2006

The Prins cyclisation has been used for the first time to desymmetrise a 1,4‐diene. Products derived from both normal Prins and rearrangement pathways were obtained, all with complete stereocontrol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Effect of near‐fault ground motion and damper characteristics on the seismic performance of chevron braced steel frames
Authors: Dicleli Murat , Mehta Anshu
Published: November 2006

This study is aimed at comparing the seismic performance of steel chevron braced frames (CBFs) with and without fluid viscous dampers (FVDs) as a function of the characteristics of the near‐fault (NF) ground motion and FVD parameters. For this purpose, comparative nonlinear time history (NLTH) analyses of single and multiple storey CBFs with and without FVDs are conducted using NF ground motions with various velocity pulse periods scaled to have small, moderate and large intensities. Additionally, NLTH analyses of single‐ and four‐storey CBFs with FVDs are conducted to study the effect of the damping ratio and velocity exponent of the FVD on the seismic performance of the frames. The analyses results revealed that the seismic performance of the CBFs without FVDs is very poor and sensitive to the velocity pulse period and the intensity of the NF ground motion due to brace‐buckling effects. Installing FVDs into the CBFs significantly improved their seismic performance by maintaining their elastic behaviour. Furthermore, FVDs with smaller velocity exponents and larger damping ratio are observed to be more effective in improving the seismic performance of the CBFs subjected to NF earthquakes. However, FVDs with damping ratios larger than 50% do not produce significant additional improvement in the seismic performance of the CBFs. Copyright © 2006 John Wiley & Sons, Ltd.
Numerical study of hysteresis in annular swirling jets with a stepped‐conical nozzle
Authors: Vanierschot M. , Van den Bulck E.
Published: November 2006

This study investigates the experimentally observed hysteresis in the mean flow field of an annular swirling jet with a stepped‐conical nozzle. The flow is simulated using the Reynolds‐averaged Navier–Stokes (RANS) approach for incompressible flow with a k–ε and a Reynolds stress transport (RSTM) turbulence model. Four different flow structures are observed depending on the swirl number: ‘closed jet flow’, ‘open jet flow low swirl’, ‘open jet flow high swirl’ and ‘coanda jet flow’. These flow patterns change with varying swirl number and hysteresis at low and intermediate swirl numbers is revealed when increasing and subsequently decreasing the swirl. The influence of the inlet velocity profile on the transitional swirl numbers is investigated. When comparing computational fluid dynamics with experiments, the results show that both turbulence models predict the four different flow structures and the associated hysteresis and multiple solutions at low and intermediate swirl numbers. Therefore, a good agreement exists between experiments and numerics. Copyright © 2006 John Wiley & Sons, Ltd.
Improving functional magnetic resonance imaging motor studies through simultaneous electromyography recordings
Authors: MacIntosh Bradley J. , Baker S. Nicole , Mraz Richard , Ives John R. , Martel Anne L. , McIlroy William E. , Graham Simon J.
Published: November 2006

Specially designed optoelectronic and data postprocessing methods are described that permit electromyography (EMG) of muscle activity simultaneous with functional MRI (fMRI). Hardware characterization and validation included simultaneous EMG and event‐related fMRI in 17 healthy participants during either ankle (n = 12), index finger (n = 3), or wrist (n = 2) contractions cued by visual stimuli. Principal component analysis (PCA) and independent component analysis (ICA) were evaluated for their ability to remove residual fMRI gradient‐induced signal contamination in EMG data. Contractions of ankle tibialis anterior and index finger abductor were clearly distinguishable, although observing contractions from the wrist flexors proved more challenging. To demonstrate the potential utility of simultaneous EMG and fMRI, data from the ankle experiments were analyzed using two approaches: 1) assuming contractions coincided precisely with visual cues, and 2) using EMG to time the onset and offset of muscle contraction precisely for each participant. Both methods produced complementary activation maps, although the EMG‐guided approach recovered more active brain voxels and revealed activity better in the basal ganglia and cerebellum. Furthermore, numerical simulations confirmed that precise knowledge of behavioral responses, such as those provided by EMG, are much more important for event‐related experimental designs compared to block designs. This simultaneous EMG and fMRI methodology has important applications where the amplitude or timing of motor output is impaired, such as after stroke. Hum Brain Mapp 2006. © 2006 Wiley‐Liss, Inc.
Hemodynamic responses in neural circuitries for detection of visual target and novelty: An event‐related fMRI study
Authors: Gur Ruben C. , Turetsky Bruce I. , Loughead James , Waxman Jonathan , Snyder Wendy , Ragland J. Daniel , Elliott Mark A. , Bilker Warren B. , Arnold Steven E. , Gur Raquel E.
Published: November 2006

The oddball paradigm examines attentional processes by establishing neural substrates for target detection and novelty. Event‐related functional imaging enables characterization of hemodynamic changes associated with these processes. We studied 36 healthy participants (17 men) applying a visual oddball event‐related design at 4 Tesla, and performed an unbiased determination of the hemodynamic response function (HRF). Targets were associated with bilateral, albeit leftward predominant changes in frontal‐parietal temporal and occipital cortices, and limbic and basal ganglia regions. Activation to novelty was more posteriorly distributed, and frontal activation occurred only on the right, while robust activation was seen in occipital regions bilaterally. Overlapping regions were left thalamus, caudate and cuneus and right parietal precuneus. While robust HRFs characterized most regions, target detection was associated with a negative HRF in the right parietal precuneus and a biphasic HRF in thalamus, basal ganglia, and all occipital regions. Both height of the HRF and longer time to peak in the right cingulate were associated with slower response time. Sex differences were observed, with higher HRF peaks for novelty in men in right occipital regions, and longer time to peak in the left hemisphere. Age was associated with reduced peak HRF in left frontal region. Thus, indices of the HRF can be used to better understand the relationship between hemodynamic changes and performance and can be sensitive to individual differences. Hum Brain Mapp 2007. © 2006 Wiley‐Liss, Inc.
Complex relationship between BOLD signal and synchronization/desynchronization of human brain MEG oscillations
Authors: Winterer Georg , Carver Frederick W. , Musso Francesco , Mattay Venkata , Weinberger Daniel R. , Coppola Richard
Published: November 2006

Functional magnetic resonance imaging (fMRI) depends on the coupling of cerebral blood flow, energy demand, and neural activity. The precise nature of this interaction, however, is poorly understood. A positive correlation between BOLD‐response and cortically generated local field potentials, which reflect the weighted average of synchronized dentrosomatic components of pyramidal synaptic signals, has been demonstrated. Likewise, positive BOLD‐responses have been reported in conjunction with scalp‐recorded synchronized electromagnetic activity by a number of groups. However, it is not yet clear how the opposite electromagnetic pattern, i.e. cortical desynchronization, is related to the BOLD signal. To address this question, we conducted a combined event‐related fMRI and 275 sensor whole‐head MEG study during identical visual two‐choice reaction time task conditions in 10 human subjects. We found complex sequences of MEG‐synchronization and desynchronization across a wide frequency range in the visual and motor area in close correspondence with “locales” of positive BOLD‐responses. These results indicate that a correspondence of positive BOLD‐responses is not exclusively found for cortical synchronization but also for desynchronization, suggesting that the relationship between BOLD signals and electromagnetic activity might be more complex than previously thought. Hum Brain Mapp 2006. © 2006 Wiley‐Liss, Inc.
‘Prefrontal’ cognitive performance of healthy subjects positively correlates with cerebral FDOPA influx: An exploratory [18F]‐fluoro‐L‐DOPA‐PET investigation
Authors: Vernaleken Ingo , Buchholz Hans‐Georg , Kumakura Yoshitaka , Siessmeier Thomas , Stoeter Peter , Bartenstein Peter , Cumming Paul , Gründer Gerhard
Published: November 2006

Dopamine neurotransmission influences those cognitive processes, which are generally regarded as prefrontal cortical functions. In previous positron‐emission‐tomography (PET) studies, net blood‐brain clearance of [18F]‐fluoro‐l‐DOPA (FDOPA) correlated with impaired cognitive performance in patients with Parkinson's disease or schizophrenia. We hypothesized that FDOPA influx also correlates with performance of cognitive tasks associated with prefrontal functioning in healthy volunteers. The net blood‐brain clearance of FDOPA (K) was mapped in a group of 11 healthy volunteers and calculated in striatal volumes‐of‐interest. The Wisconsin‐Card‐Sorting‐Test (WCST), Stroop‐Test, Trail‐Making‐Test (TMT‐A/B), and Continuous‐Performance‐Test (CPT‐M) had been administered previously to the same subjects. No correlation of K with perseverative errors in WCST or age could be found. However, there were significant positive correlations between the magnitude of K in caudate nucleus, putamen, and midbrain with performance of the TMT‐B, CPT‐M, and the Stroop test. Highest correlations were found between the time needed to perform the Stroop interference task and the K of striatal areas (Caudate nucleus: −0.780, P = 0.005; putamen: −0.870, P < 0. 001). Thus, the present findings reveal a strong correlation between dopamine synthesis capacity in striatum of healthy volunteers and performance of cognitive tasks linked to the prefrontal cortex. Hum Brain Mapp 2006. © 2006 Wiley‐Liss, Inc.
Prediction of recurrence of hepatocellular carcinoma after curative ablation using three tumor markers
Authors: Tateishi Ryosuke , Shiina Shuichiro , Yoshida Haruhiko , Teratani Takuma , Obi Shuntaro , Yamashiki Noriyo , Yoshida Hideo , Akamatsu Masatoshi , Kawabe Takao , Omata Masao
Published: November 2006

Three tumor markers for hepatocellular carcinoma (HCC) are available in daily practice in Japan: alpha-fetoprotein (AFP), des-gamma-carboxy prothrombin (DCP), and lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3). To elucidate the predictability of these tumor markers on HCC recurrence after curative ablation, we enrolled 416 consecutive patients with naïve HCC who had been treated by percutaneous ablation at our department from July 1997 to December 2002. Tumor marker levels were determined immediately before and 2 months after the treatment. Complete ablation was defined on CT findings as nonenhancement in the entire lesion with a safety margin. Tumor recurrence was also defined as newly developed lesions on CT that showed hyperattenuation in the arterial phase with washout in the late phase. We assessed the predictability of recurrence via tumor markers in multivariate analysis, using proportional hazard regression after adjusting for other significant factors in univariate analysis. Until the end of follow-up, tumor recurrence was identified in 277 patients. Univariate analysis revealed the following factors to be significant for recurrence: platelet count; size and number of tumors; AFP, AFP-L3, and DCP preablation; and AFP and AFP-L3 postablation. Multivariate analysis indicated that AFP >100 ng/mL and AFP-L3 >15%, both pre- and postablation, were significant predictors. The positivity of AFP and AFP-L3 preablation that turned negative postablation was not significant.

In conclusion

, tumor markers pre- and post-ablation were significant predictors for HCC recurrence and can complement imaging modalities in the evaluation of treatment efficacy.
Cost-effectiveness of hematologic growth factors for anemia occurring during hepatitis C combination therapy
Authors: Del Rio Richard A. , Post Anthony B. , Singer Mendel E.
Published: November 2006

In hepatitis C virus (HCV)-infected patients who develop anemia during combination therapy, erythropoietic growth factors maintain higher drug treatment levels compared to ribavirin dose reduction, which may lead to an increase in treatment response rates. This study estimated the cost-effectiveness of growth factor therapy in maintaining anemic HCV-infected patients on target drug levels during combination therapy. A decision analysis using a Markov model was developed with 7 health states: Sustained viral response, chronic HCV, compensated cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, liver transplantation, and death. Data sources included population-based studies of growth factor therapy, previously published estimates of costs and natural history of hepatitis C, and recent prospective studies. Our reference case was a 45-year-old Caucasian man with HCV infection (genotype 1, 2, or 3) who developed anemia while undergoing combination therapy with ribavirin and pegylated interferon. We compared growth factor injections (darbepoetin alpha or epoetin alpha) during combination therapy with standard ribavirin dose reduction. Compared to a ribavirin dose reduction strategy, the cost of darbepoetin per additional quality-adjusted life-year was $34,793 for genotype 1 and $33,832 for genotypes 2 or 3 versus $60,600 and $64,311 for epoetin. For all genotypes, the results were sensitive to changes in the cure rates of HCV therapy, the utility of chronic HCV, the costs of growth factors, and the age at which therapy is begun.

In conclusion

, use of erythropoietic growth factors, specifically darbepoetin, for patients with anemia occurring during HCV combination therapy appears to be cost-effective for genotypes 1, 2, or 3.
Monocrotaline promotes transplanted cell engraftment and advances liver repopulation in rats via liver conditioning
Authors: Joseph Brigid , Kumaran Vinay , Berishvili Ekaterine , Bhargava Kuldeep K. , Palestro Christopher J. , Gupta Sanjeev
Published: November 2006

Disruption of the hepatic endothelial barrier or Kupffer cell function facilitates transplanted cell engraftment in the liver. To determine whether these mechanisms could be activated simultaneously, we studied the effects of monocrotaline, a pyrollizidine alkaloid, with reported toxicity in liver sinusoidal endothelial cells and Kupffer cells. The effects of monocrotaline in Fischer 344 rats were examined by tissue morphology, serum hyaluronic acid levels, and liver tests (endothelial and hepatocyte injury) or incorporation of carbon and 99mTc-sulfur colloid (Kupffer cell damage). To study changes in cell engraftment and liver repopulation, Fischer 344 rat hepatocytes were transplanted into syngeneic dipeptidyl peptidase IV–deficient rats followed by histological assays. We observed extensive endothelial injury without Kupffer cell or hepatocyte damage in monocrotaline-treated rats. Monocrotaline enhanced transplanted cell engraftment without changes in transplanted cell numbers or induction of proliferation in native hepatocytes over 3 months. In monocrotaline-treated rats, transplanted cells integrated into the liver parenchyma and survived in vascular spaces. To determine whether native hepatocytes suffered inapparent damage after monocrotaline, we introduced further liver injury with carbon tetrachloride subsequent to cell transplantation. Monocrotaline sensitized the liver to carbon tetrachloride–induced necrosis, which advanced transplanted cell proliferation, leading to significant liver repopulation. During this process, we observed proliferation of bile duct cells and small epithelial cells, although transplanted hepatocytes did not appear to reconstitute bile ducts. The studies showed that perturbation of multiple liver cell compartments by monocrotaline promoted transplanted cell engraftment and proliferation.

In conclusion

, development of drugs with monocrotaline-like effects will help advance liver cell therapy.
Entecavir resistance is rare in nucleoside naïve patients with hepatitis B
Authors: Colonno Richard J. , Rose Ronald , Baldick Carl J. , Levine Steven , Pokornowski Kevin , Yu Cheng F. , Walsh Ann , Fang Jie , Hsu Mayla , Mazzucco Charles , Eggers Betsy , Zhang Sharon , Plym Mary , Klesczewski Kenneth , Tenney Daniel J.
Published: November 2006

Comprehensive monitoring of genotypic and phenotypic antiviral resistance was performed on 673 entecavir (ETV)-treated nucleoside naïve hepatitis B virus (HBV) patients. ETV reduced HBV DNA levels to undetectable by PCR (<300 copies/mL, <57 IU/mL) in 91% of hepatitis B e antigen (HBeAg)-positive and -negative patients by Week 96. Thirteen percent (n = 88) of the comparator lamivudine (LVD)-treated patients experienced a virologic rebound (≥1 log increase from nadir by PCR) in the first year, with 74% of these having LVD resistance (LVDr) substitutions evident. In contrast, only 3% (n = 22) of ETV-treated patients exhibited virologic rebound by Week 96. Three ETV rebounds were attributable to LVDr virus present at baseline, with one having a S202G ETV resistance (ETVr) substitution emerge at Week 48. None of the other rebounding patients had emerging genotypic resistance or loss of ETV susceptibility. Genotyping all additional ETV patients with PCR-detectable HBV DNA at Weeks 48, 96, or end of dosing identified seven additional patients with LVDr substitutions, including one with simultaneous emergence of LVDr/ETVr. Generally, ETV patients with LVDr were detectable at baseline (8/10) and most subsequently achieved undetectable HBV DNA levels on ETV therapy (7/10). No other emerging substitutions identified decreased ETV susceptibility.

In conclusion

, ETVr emergence in ETV-treated nucleoside naïve patients over a 2-year period is rare, occurring in two patients with LVDr variants. These findings suggest that the rapid, sustained suppression of HBV replication, combined with a requirement for multiple substitutions, creates a high genetic barrier to ETVr in nucleoside naïve patients.