bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluorinated β‐Diketones for the Extraction of Lanthanide Ions: Photophysical Properties and Hydration Numbers of Their EuIII Complexes
Authors: Chauvin Anne‐Sophie , Gumy Frédéric , Matsubayashi Izuru , Hasegawa Yuko , Bünzli Jean‐Claude G. 
Published: December 2005

AbstractTris(β‐diketonato)europium(III) with a series of variably fluorinated ligands derived from 3,5‐heptanedione were synthesised with the aim of determining their hydration state under extraction conditions. The number of coordinated water molecules was determined by measuring the lifetime of the Eu(5D0) excited level in water and deuterated water. The hydration gain (Δq = q – q0) after shaking chloroform solutions during 10 min with 0.1 M NaClO4 aqueous solutions depends on the fluorination extent of the diketonates: fluorination of one methyl group leads to a decrease in Δq of ca. 0.5 unit, while fluorination of one ethyl group results in a decrease of ca. 1.3 units. Highly fluorinated complexes (i.e with hexafluoroacetylacetonate and related ligands) display a hydration number close to one while poorly fluorinated compounds (or nonfluorinated ones, such as the acetylacetonate complex) have a hydration state close to two. Photophysical properties of the EuIII β‐diketonates are also described and the synthesis of the fluorinated β‐diketones is re‐investigated and discussed in details. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis of Amino‐ and Bis(bromomethyl)‐Substitued Bi‐ and TetradentateN‐Heteroaromatic Ligands: Building Blocks for Pyrazino‐Functionalized Fullerene Dyads
Authors: Kleineweischede Andreas , Mattay Jochen 
Published: December 2005

AbstractIn this paper we describe the synthesis of amino‐ and bis(bromomethyl)‐substituted derivatives of phenanthroline (phen), pyrazino[2,3‐f]‐phenanthroline (pphen), dipyrido[3,2‐a:2′,3′‐c]phenazine (dppz), pyrazino[2,3‐i]dipyrido[3,2‐a:2′,3′‐c]phenazine, 2,3‐bis(2‐pyridyl)pyrazine (dpp), 2,3‐bis(2‐pyridyl)quinoxaline (dpq) and 7,8‐bis(2‐pyridyl)pyrazino[2,3‐g]quinoxaline. These substituted bi‐ and tetradentate N‐heteroaromatic ligands are potential synthons for the preparation of the fullerene ligands 4–9. The diketones, 1,10‐phenanthroline‐5,6‐dione 11a (phendione), 2,2‐pyridyl 11b and 1,4‐dibromo‐2,3‐butanedione 33 were used as starting materials. Phendione was converted into the phendiamine 13 by a two‐step synthesis via the dioxime of the diketone 11a. Amino‐substituted dppz and dpq derivatives were obtained by the reduction of the corresponding nitro compounds that were obtained by the Schiff base condensation of the diketones 11a and 11b and the appropriate o‐phenylenediamine derivatives. An alternative synthetic route to the diamines 20a and 20b by detosylation of the diamino‐substituted dppzand dpq ligands is also presented. Synthesis of the bis(bromomethyl)‐substituted pphen, dpp, dppz and dpq derivatives was performed by the photochemical addition of bromine. Alternatively, synthesis of the bis(bromomethyl)‐substituted pphen, pdppz and pdpq is also possible by the condensation of 1,4‐dibromo‐2,3‐butanedione 33 and phendiamine or the diamino‐substituted dppz and dpq derivatives. The latter two compounds can be also prepared by the condensation of diketones 11a and 11b with 6,7‐diamino‐2,3‐bis(bromomethyl)quinoxaline. Although the synthesis of some dppz and dpq ligands is already published, we herein present improved or alternative synthetic strategies leading to higher yields and/or higher purity of these N‐heteroaromatic ligands. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Linking the 3′ Ends of Oligonucleotide Duplexes with Cystine Disulfide Bridges
Authors: Marchán Vicente , Pulido Daniel , Pedroso Enrique , Grandas Anna 
Published: December 2005

AbstractOligonucleotide duplexes with cystine disulfide 3′‐3′ interstrand cross‐links were synthesized. Stepwise solid‐phase procedures, followed by basic deprotection under controlled conditions and air oxidation, afforded various disulfide‐linked duplexes differing in the peptide and oligonucleotide composition and length. Some of these nucleopeptides form unimolecular duplexes in which peptide–minor‐groove interactions are established, while others may give rise to extended nanostructures. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis and Antiviral Evaluation of Carbocyclic 3′‐Azidothymidine (AZT) Analogues and Their cycloSal‐Phosphate Triesters
Authors: Ludek Olaf R. , Balzarini Jan , Meier Chris 
Published: December 2005

AbstractCarbocyclic analogues of the anti‐HIV dideoxynucleoside 3′‐azido‐3′‐deoxythymidine AZT (1) were synthesized. Starting from the enantiomerically pure carbocyclic 2′‐deoxythymidine 2, four different carbocyclic AZT analogues 2,4–6 were prepared. Moreover, the nucleoside analogues were converted into their membrane‐permeable cycloSal‐phosphate triesters. All compounds were tested in vitro for their anti‐HIV activity in human T‐lymphocytes (CEM/0). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Determination of different classes of amines with capillary zone electrophoresis and contactless conductivity detection
Authors: Gong Xiao Yang , Hauser Peter C. 
Published: December 2005

AbstractThe use of contactless conductivity detection for the determination of different organic amines in CE was successfully demonstrated. Aliphatic nonUV‐absorbing species could be determined along absorbing compounds by measuring the conductivity of their protonated forms. The species tested included short‐chained aliphatic primary, secondary and tertiary amines, branched aliphatic amines, diamines, hydroxyl‐substituted amines as well as species incorporating aromatic and nonaromatic cyclic moieties. Highest sensitivity was obtained with BGE solutions containing solely acetic acid. A concentration of 0.5 M at a pH value of 2.5 was used. Detection limits were in the order of 1 μM. Complete separation of cis‐ and trans‐1,2‐diaminocyclohexane could be achieved by adding 18‐crown‐6 as modifier to the electrolyte solution.
A new multiphasic buffer system for benzyldimethyl‐n‐hexadecylammonium chloride polyacrylamide gel electrophoresis of proteins providing efficient stacking
Authors: Kramer Michael L. 
Published: December 2005

AbstractAcidic PAGE systems using cationic detergents such as benzyldimethyl‐n‐hexadecylammonium chloride (16‐BAC) or CTAB have proven useful for the detection of methoxy esters sensitive to alkaline pH, resolving basic proteins such as histones and membrane proteins. However, the interesting phosphate‐based system suffered from poor stacking, resulting in broadened bands and long running times. Therefore, a new 16‐BAC PAGE system based on the theory of moving boundary electrophoresis with properties comparable to the classical SDS‐PAGE system was designed. As a result a new multiphasic analytical 16‐BAC PAGE system providing efficient stacking and significantly shorter running times is presented here. It is based on acetic acid and methoxyacetic acid as common ion constituents. This PAGE system takes advantage of the additional counterstacking effect due to a cross boundary electrophoresis system resulting from the selected buffer constituents. Furthermore, the concentration of 16‐BAC was optimized by determining its previously unknown CMC. Due to efficient focusing of the introduced tracking dye, methyl green, termination of electrophoresis can now be more easily followed as compared to the Schlieren line.
Enhanced spontaneous metastasis in bikunin‐deficient mice
Authors: Yagyu Tatsuo , Kobayashi Hiroshi , Matsuzaki Hidenori , Wakahara Kiyoshi , Kondo Toshiharu , Kurita Noriyuki , Sekino Hideo , Inagaki Kiyokazu 
Published: December 2005

AbstractPreviously, we showed that bikunin, a Kunitz‐type protease inhibitor, inhibits invasion and metastasis in several types of cancer cells possibly through suppression of upregulation of urokinase‐type plasminogen activator (uPA) expression. Bikunin corresponds to a light chain of the inter‐alpha inhibitor. To explore critical role of endogenous bikunin, we used bikunin knockout (Bik−/−) mice. Here, we show that 1) higher frequency of spontaneous 3LL lung metastasis was observed in Bik−/− mice compared to Bik+/+ mice, suggesting that bikunin deficiency increases the sensitivity of mice to lung metastasis; 2) administration of exogenous bikunin caused a significant reduction of lung metastasis in Bik−/− and Bik+/+ mice; 3) primary and metastatic tumors significantly upregulated uPA and PAI‐1 expression in Bik−/− mice relative to Bik+/+ mice at least through phosphorylation of ERK1/2 and 4) exogenous bikunin suppressed phosphorylation of ERK1/2 and upregulation of uPA and PAI‐1 expression in 3LL cells in response to G‐CSF. These data allow us to conclude that the increased sensitivity of Bik−/− mice to lung metastasis in vivo is due to a lack of circulating proteins of the inter‐alpha inhibitor family, especially bikunin. © 2005 Wiley‐Liss, Inc.
Diet and body mass, and oral and oropharyngeal squamous cell carcinomas: Analysis from the IARC multinational case–control study
Authors: Kreimer Aimée R. , Randi Giorgia , Herrero Rolando , Castellsagué Xavier , Vecchia Carlo La , Franceschi Silvia 
Published: December 2005

AbstractTobacco and alcohol use are the main risk factors for oral and oropharyngeal cancers, yet, dietary habits may also be of importance. Data from a series of case–control studies conducted in 9 countries worldwide (1,670 cases and 1,732 controls) were used to investigate the role of several food groups and body mass index (BMI). Low BMI significantly increased the odds ratio (OR) of cancer more than 2‐fold among ever‐ and never‐tobacco users and ever‐ and never‐alcohol drinkers. After adjustment for potential confounders, high intake of fruits and vegetables significantly reduced the OR of cancer compared to low intake among ever‐tobacco users (OR 0.4, 95% confidence interval [CI] 0.3–0.6), although not among never‐tobacco users (OR 1.1, 95% CI 0.6–2.0). Similarly, the protective effect of high fruit and vegetable consumption was present among ever‐drinkers (OR 0.4, 95% CI 0.3–0.6), but not among never‐drinkers (OR 1.0, 95% CI 0.6–1.6). In conclusion, low BMI increases the risk of oral cancer, and vegetables and fruits may modulate the carcinogenic effects of tobacco and alcohol. © 2005 Wiley‐Liss, Inc.
Multilocus inheritance determines predisposition to α‐radiation induced bone tumourigenesis in mice
Authors: Rosemann Michael , Kuosaite Virginija , Kremer Markus , Favor Jack , Quintanilla‐Martinez Leticia , Atkinson Michael J. 
Published: December 2005

AbstractIn a recent study, we presented evidence for genetic predisposition governing radiation osteosarcomagenesis in mice. Following the incorporation of the bone‐seeking α emitter 227Th, ˜25% of the variance in osteosarcoma incidence was determined by inherited genetic factors. We have now mapped 5 susceptibility loci in crosses between the more susceptible BALB/c and the more resistant CBA/Ca strains. The major QTL on chromosome 14 overlaps with a locus that was already found in our previous study, using different strains of mice. Here, we investigate the effect by which the major susceptibility locus and 4 minor modifier loci interact to influence osteosarcoma predisposition. Following incorporation of the bone‐seeking isotope, 100% of mice that harbour high‐risk genotypes at all 5 susceptibility loci develop osteosarcoma with an average of 472 days latency times. In 10 mice inheriting exclusively low‐risk genotypes only 1 osteosarcoma was found, arising after 733 days latency time. Inheritance of distinct combinations of BALB/c and CBA/Ca alleles at the susceptibility loci confer more extreme phenotypes in terms of susceptibility or resistance than observed in either of the two parental inbred strains. From the present study, we demonstrate that additive effects of multiple alleles, each making only a minor phenotypic contribution, can combine and significantly alter tumour risk. This mechanism can be of particular importance in genetically heterogeneous populations such as man. © 2005 Wiley‐Liss, Inc.
Prevention of mouse lung tumors by targretin
Authors: Pereira Michael A. , Kramer Paula M. , Nines Ronald , Liu Yue , Alyaqoub Fadel S. , Gunning William T. , Steele Vernon E. , Lubet Ronald A. 
Published: December 2005

AbstractTargretin has indicated chemotherapeutic activity against nonsmall‐cell lung cancer and chemoprevention in rat mammary gland. Therefore, targretin was evaluated for the prevention of 4‐(methylnitrosoamino)‐1‐(3‐pyridyl)‐1‐butanol (NNK) and vinyl carbamate‐induced lung tumors in female strain A mice. Three experiments were performed: (i) a dose‐response study with vinyl carbamate‐induced tumors; (ii) a limited treatment study also with vinyl carbamate and (iii) prevention of NNK‐induced tumors. In the dose‐response study, 0, 10, 30, 100 and 300 mg/kg targretin were administered after vinyl carbamate. Dose levels of 30 mg/kg and greater significantly decreased tumor multiplicity by >19%. However, the efficacy of 30 and 300 mg/kg was not significantly different demonstrating a shallow dose‐response relationship. In the limited treatment study, 200 mg/kg targretin was administered to the mice from 4–13, 4–19, 4–25 and 23–25 weeks after vinyl carbamate. Administering targretin from weeks 4–19 and 4–25 decreased the multiplicity of tumors from 35.3 ± 1.43 to 29.1 ± 1.51 and 25.0 ± 0.93, respectively, and along with administering it from weeks 23–25 decreased tumor size. In the third study, when targretin (100 and 300 mg/kg) was administered for 3 weeks after NNK followed by a 20 weeks holding period, tumor multiplicity was reduced from 10.6 ± 1.13 to 6.38 ± 0.75 and 4.60 ± 0.70, respectively. Hence, targretin demonstrated both preventive and therapeutic activity with respect to mouse lung tumors supporting its further development as a preventive and therapeutic agent for lung cancer. © 2005 Wiley‐Liss, Inc.
Combination therapy with 2‐difluoromethylornithine and a polyamine transport inhibitor against murine squamous cell carcinoma
Authors: Chen Yan , Weeks Reitha S. , Burns Mark R. , Boorman David W. , Klein‐Szanto Andres , O'Brien Thomas G. 
Published: December 2005

AbstractUsing a recently developed autochthonous mouse model of squamous cell carcinoma (SCC), a combination therapy targeting polyamine metabolism was evaluated. The therapy combined 2‐difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase (ODC), and MQT 1426, a polyamine transport inhibitor. In 1 trial lasting 4 weeks, combination therapy with 0.5% DFMO (orally, in the drinking water) and MQT 1426 (50 mg/kg i.p., bid) was significantly more effective than with either single agent alone when complete tumor response was the endpoint. In the combination group, 72% of SCCs responded completely vs. 21 and 0% for DFMO and MQT 1426, respectively. A second trial involved a 4‐week treatment period followed by 6 weeks off‐treatment. With apparent cures as an endpoint, combination therapy was again more effective than either agent alone: a 50% apparent cure rate was observed in the combination group vs. 7.7% in the DFMO group. MQT 1426 had no inhibitory effect on SCC ODC activity nor did it enhance the inhibition by DFMO, but SCC polyamine levels declined more rapidly when treated with combination therapy vs. DFMO alone. The apoptotic index in SCCs was transiently increased by combination therapy but not by DFMO alone. Thus, targeting both polyamine biosynthesis and polyamine transport from the tumor microenvironment enhances the efficacy of polyamine‐based therapy in this mouse model of SCC. © 2005 Wiley‐Liss, Inc.
Identification of three major DNA adducts formed by the carcinogenic air pollutant 3‐nitrobenzanthrone in rat lung at the C8 and N2 position of guanine and at the N6 position of adenine
Authors: Arlt Volker M. , Schmeiser Heinz H. , Osborne Martin R. , Kawanishi Masanobu , Kanno Takaharu , Yagi Takashi , Phillips David H. , Takamura‐Enya Takeji 
Published: December 2005

Abstract3‐Nitrobenzanthrone (3‐NBA) is a potent mutagen and potential human carcinogen identified in diesel exhaust and ambient air particulate matter. Previously, we detected the formation of 3‐NBA‐derived DNA adducts in rodent tissues by 32P‐postlabeling, all of which are derived from reductive metabolites of 3‐NBA bound to purine bases, but structural identification of these adducts has not yet been reported. We have now prepared 3‐NBA‐derived DNA adduct standards for 32P‐postlabeling by reacting N‐acetoxy‐3‐aminobenzanthrone (N‐Aco‐ABA) with purine nucleotides. Three deoxyguanosine (dG) adducts have been characterised as N‐(2′‐deoxyguanosin‐8‐yl)‐3‐aminobenzanthrone‐3′‐phosphate (dG3′p‐C8‐N‐ABA), 2‐(2′‐deoxyguanosin‐N2‐yl)‐3‐aminobenzanthrone‐3′‐phosphate (dG3′p‐N2‐ABA) and 2‐(2′‐deoxyguanosin‐8‐yl)‐3‐aminobenzanthrone‐3′‐phosphate (dG3′p‐C8‐C2‐ABA), and a deoxyadenosine (dA) adduct was characterised as 2‐(2′‐deoxyadenosin‐N6‐yl)‐3‐aminobenzanthrone‐3′‐phosphate (dA3′p‐N6‐ABA). 3‐NBA‐derived DNA adducts formed experimentally in vivo and in vitro were compared with the chemically synthesised adducts. The major 3‐NBA‐derived DNA adduct formed in rat lung cochromatographed with dG3′p‐N2‐ABA in two independent systems (thin layer and high‐performance liquid chromatography). This is also the major adduct formed in tissue of rats or mice treated with 3‐aminobenzanthrone (3‐ABA), the major human metabolite of 3‐NBA. Similarly, dG3′p‐C8‐N‐ABA and dA3′p‐N6‐ABA cochromatographed with two other adducts formed in various organs of rats or mice treated either with 3‐NBA or 3‐ABA, whereas dG3′p‐C8‐C2‐ABA did not cochromatograph with any of the adducts found in vivo. Utilizing different enzymatic systems in vitro, including human hepatic microsomes and cytosols, and purified and recombinant enzymes, we found that a variety of enzymes [NAD(P)H:quinone oxidoreductase, xanthine oxidase, NADPH:cytochrome P450 oxidoreductase, cytochrome P450s 1A1 and 1A2, N,O‐acetyltransferases 1 and 2, sulfotransferases 1A1 and 1A2, and myeloperoxidase] are able to catalyse the formation of 2‐(2′‐deoxyguanosin‐N2‐yl)‐3‐aminobenzanthrone, N‐(2′‐deoxyguanosin‐8‐yl)‐3‐aminobenzanthrone and 2‐(2′‐deoxyadenosin‐N6‐yl)‐3‐aminobenzanthrone in DNA, after incubation with 3‐NBA and/or 3‐ABA. © 2005 Wiley‐Liss, Inc.
Different angiogenic phenotypes in primary and secondary glioblastomas
Authors: Karcher Sibylle , Steiner Hans‐Herbert , Ahmadi Rezvan , Zoubaa Saida , Vasvari Gergely , Bauer Harry , Unterberg Andreas , Herold‐Mende Christel 
Published: December 2005

AbstractPrimary and secondary glioblastomas (pGBM, sGBM) are supposed to evolve through different genetic pathways, including EGF receptor and PDGF and its receptor and thus genes that are involved in tumor‐induced angiogenesis. However, whether other angiogenic cytokines are also differentially expressed in these glioblastoma subtypes is not known so far, but this knowledge might be important to optimize an antiangiogenic therapy. Therefore, we studied the expression of several angiogenic cytokines, including VEGF‐A, HGF, bFGF, PDGF‐AB, PDGF‐BB, G‐CSF and GM‐CSF in pGBMs and sGBMs as well as in gliomas WHO III, the precursor lesions of sGBMs. In tumor tissues, expression of all cytokines was observed albeit with marked differences concerning intensity and distribution pattern. Quantification of the cytokines in the supernatant of 30 tissue‐corresponding glioma cultures revealed a predominant expression of VEGF‐A in pGBMs and significantly higher expression levels of PDGF‐AB in sGBMs. HGF and bFGF were determined in nearly all tumor cultures but with no GBM subtype or malignancy‐related differences. Interestingly, GM‐CSF and especially G‐CSF were produced less frequently by tumor cells. However, GM‐CSF secretion occurred together with an increased number of simultaneously secreted cytokines and correlated with a worse patient prognosis and may thus represent a more aggressive angiogenic phenotype. Finally, we confirmed an independent contribution of each tumor‐derived cytokine analyzed to tumor‐induced vascularization. Our data indicate that an optimal antiangiogenic therapy may require targeting of multiple angiogenic pathways that seem to differ markedly in pGBMs and sGBMs. © 2005 Wiley‐Liss, Inc.
Development in incidence of breast cancer in non‐screened danish women, 1973–2002—a population‐based study
Authors: Fuglede Niels , Langballe Oline , Svendsen Anne Louise , Tjønneland Anne , Dalton Susanne O , Johansen Christoffer 
Published: December 2005

AbstractThe authors report on the incidence rates of breast cancer overall and by histology in a population of unscreened women constituting ∼80% of the total population of women in Denmark from 1973–2002, utilizing the files of the nationwide Danish Cancer Registry. The age‐specific incidence rates of breast cancer increased throughout the period, and further, marked changes in the age‐specific incidence pattern were observed, where the plateau and change of slope around the age of 46–48 in 1973–1981 shifted to around age 64–66 years in 1994–2002. Age‐period‐cohort modeling indicated that these changes were not attributable to a birth cohort effect. Although lobular breast cancer incidence increased more than ductal breast cancer incidence, this was only observed in the first decade after the introduction of the ICD‐O system in Denmark and probably is attributable to this, whereas we observed no disproportionate changes by histology in any age group from 1988–2002. Thus, previous reports of a disproportionate increase in lobular breast cancer could not be confirmed in a non‐screened population, whereas important changes over the past decade in the age‐specific incidence pattern of breast cancer particular around the time of menopause were indicated. © 2005 Wiley‐Liss, Inc.
TRAIL‐induced cell death cooperates with IFN‐γ activation in the graft‐versus‐tumor effect against colon tumors
Authors: Tateishi Keisuke , Ohta Miki , Guleng Bayasi , Kanai Fumihiko , Tanaka Yasuo , Asaoka Yoshinari , Jazag Amarsanaa , Imamura Jun , Imamura Takaaki , Ijichi Hideaki , Ikenoue Tsuneo , Kawakami Takayuki , Fukushima Yasushi , Washida Miwa , Sata Masataka , Miyagishi Makoto , Taira Kazunari , Yoshida Haruhiko , Kawabe Takao , Omata Masao 
Published: December 2005

AbstractThe graft‐versus‐tumor (GVT) effect that occurs following allogeneic bone marrow transplantation (BMT) and donor lymphocyte infusion (DLI) is currently being subjected to intensive investigation because of clinical evidence for GVT efficacy against leukemia. In this report, we investigate the efficacy and molecular mechanisms of GVT against solid tumors, using a modification of the mouse parent‐to‐F1 BMT model. Mouse Colon26 cells in which tumor necrosis factor related apoptosis‐inducing ligand (TRAIL) receptor expression was stably knocked down were transplanted to investigate the role of the TRAIL‐TRAIL receptor system in the GVT effect. In addition, Fas ligand‐(FasL) deficient mice on a C57BL6 (B6) background were used as donors, to determine the significance of the Fas‐FasL system for the antitumor effect. The group that received B6 DLI followed by preconditioning with 950 rad irradiation underwent tumor reduction associated with the induction of IFN‐γ, TRAIL and tumor‐cell apoptosis. In vitro cultured Colon26 cells were resistant to TRAIL but susceptible to the combination of IFN‐γ and TRAIL in a TRAIL‐dose‐dependent manner. The infusion of lymphocytes from FasL‐defective donors reduced the tumor progression, although efficacy was decreased in the TRAIL receptor knockdown tumors but not in wild‐type ones, compared with infusion of B6‐derived lymphocytes. The findings indicate that GVT activity against subcutaneous colon tumors is efficiently induced by preconditioning with irradiation and allogeneic DLI, and that TRAIL and IFN‐γ act cooperatively in the antitumor effect. © 2005 Wiley‐Liss, Inc.