bluuebunny/crossref_metadata_2025_split huggingface dataset:
End‐Capped, Conjugated (Dimethylamino)naphthyl Nanostructures with Alternating (1‐Naphthylethynyl‐p‐phenylethynyl)x Branches on a 1,3,5‐Substituted Benzene Core
Authors: Rodríguez J. Gonzalo , Tejedor J. Luis 
Published: January 2005

AbstractAlternating (1‐naphthylethynyl‐p‐phenylethynyl)x 1,3,5‐trisubstituted benzene dendrons were efficiently synthesised by the heterocoupling reaction between (1‐naphthylethynyl‐p‐phenyl)xacetylene (x = 1) and 1,3,5‐triiodobenzene in the presence of a palladium‐copper catalyst system. A longer terminal acetylene chain (x = 2) was obtained from the heterocoupling between 1,3,5‐tri(1‐ethynyl‐5‐naphthylethynyl)benzene and the appropriate iodoaryl derivative. The alternating chains, and their dendron structures, show fluorescence emission, with similar wavelengths and quantum yields. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Reinvestigation of the Mechanism of gem‐Diacylation: Chemoselective Conversion of Aldehydes to Various gem‐Diacylates and Their Cleavage under Acidic and Basic Conditions
Authors: Kavala Veerababurao , Patel Bhisma K. 
Published: January 2005

AbstractThe mechanism of gem‐diacylate formation has been studied extensively using tetrabutylammonium tribromide (TBATB) as the catalyst. The reaction proceeds by a nucleophilic attack of an anhydride on an aldehydic carbonyl group, nucleophilic attack of the hemiacylate intermediate on a second molecule of the anhydride, followed by an intermolecular attack of a second acetate group to regenerate the anhydride. gem‐Diacylates of various aliphatic and aromatic aldehydes were obtained directly from the reaction of a variety of aliphatic and aromatic acid anhydrides in the presence of a catalytic quantity of tetrabutylammonium tribromide (TBATB) under solvent‐free conditions. A significant electronic effect was observed during its formation as well as deprotection to the corresponding aldehyde. Chemoselective gem‐diacylation of the aromatic aldehyde containing an electron‐donating group has been achieved in the presence of an aldehyde containing an electron‐withdrawing group. Deprotection of the gem‐diacylate to the parent carbonyl compound can be accomplished in methanol in presence of the same catalyst. Here again, chemoselective deprotection of the gem‐diacylate of a substrate containing an electrondonating group has been achieved in the presence of a substrate containing an electron‐withdrawing group. Both the acid and base stability order of the various gem‐diacylates examined follow a similar order. The stability order determined from the present study is: gem‐dibenzoate > gemdipivalate > gem‐diisobutyrate > gem‐diacetate > gem‐dipropionate. All the gem‐diacylals are more stable under basic conditions than acidic condition. No correlation was found between the stability order and the pKa’s of the corresponding acids; rather, the stability order is directly related to the steric crowding around the carbonyl carbon. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
A Remarkably Efficient Markovnikov Hydrochlorination of Olefins and Transformation of Nitriles into Imidates by Use of AcCl and an Alcohol
Authors: Yadav Veejendra K. , Babu K. Ganesh 
Published: January 2005

AbstractHCl generated by mixing AcCl with EtOH brings about Markovnikov hydrochlorination of olefins in excellent yields. The products are isolated in states of high purity simply by removal of the volatile components under reduced pressure. Further, nitriles are transformed into imidate hydrochlorides on similar treatment with AcCl and an alcohol. This procedure for nitrile‐imidate transformation is much more efficient than that used previously, which involved continuous passing of HCl gas into the solution of a nitrile in a solvent such as Et2O or benzene and an alcohol until one equivalent had been absorbed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
An Efficient Synthesis of Novel α‐Aminophosphonates Based on a Mannich‐Type Reaction
Authors: Risch Nikolaus , Piper Stefan , Winter Andreas , Lefarth‐Risse Annette 
Published: January 2005

AbstractPhosphonate‐substituted iminium salt2was used in Mannich reactions with various nucleophiles to obtain novel α‐aminophosphonates. This straightforward and efficient methodology has a broad scope and provides highly functionalized Mannich bases (4and8). Furthermore, vinylic, aromatic and homoallylic α‐aminophosphonates (5,10and12) were synthesized in good yields. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Fluorinations of α‐Seleno Carboxylic Acid Derivatives with Hypervalent (Difluoroiodo)toluene
Authors: Arrica Maria A. , Wirth Thomas 
Published: January 2005

AbstractA very efficient synthesis of (difluoroiodo)toluene avoiding the use of elemental chlorine and elemental fluorine is described. We have fluorinated a series of α‐acceptor substituted selenides using (difluoroiodo)toluene. The reactions are usually very clean and under the reaction conditions no further oxidized products are observed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Cover Picture: Palladium‐Catalyzed Arylation of Linear and Cyclic Polyamines (Eur. J. Org. Chem. 2/2005)
Authors: Beletskaya Irina P. , Bessmertnykh Alla G. , Averin Alexei D. , Denat Franck , Guilard Roger 
Published: January 2005

AbstractThe cover picture shows the model structures of four compounds among the hundred of arylated linear and cyclic polyamines prepared by palladium‐catalyzed coupling of mono‐ and dihalogenoarenes with various aliphatic or aromatic polyamines. The reaction is strongly dependent on the nature and the concentration of the catalytic system, as well as the nature of the base. The competitive reaction between primary and secondary amines and the monoamination of dihalobenzenes have also been detailed in the article by R. Guilard et al. on p. 261 ff. In the following article by the same authors on p. 281 ff, the method has been applied to the synthesis of numerous nitrogen‐ and oxygen‐containing macrocycles incorporating anthracene or anthraquinone moieties.
Differential induction and activation of NF‐κB transcription complexes in radiation‐induced chromosomally unstable cell lines
Authors: Snyder Andrew R. , Morgan William F. 
Published: January 2005

AbstractRadiation‐induced genomic instability is a delayed effect of ionizing radiation that may contribute to radiation carcinogenesis. Prior microarray studies investigating gene expression changes in genomically unstable cell lines isolated after radiation exposure uncovered the differential expression of the NF‐κB p105 mRNA. In this study, the functionality of the NF‐κB pathway was examined to determine its role in regulating gene expression changes after oxidative stress in chromosomally stable and unstable human‐hamster hybrid clones. Basal DNA‐binding activity assays showed no significant differences between the clones; however, further experiments established differences in NF‐κB induction in three chromosomally unstable clones after acute hydrogen peroxide treatment. A second assay was used to confirm this differential activity in the chromosomally unstable clones by studying reporter gene activation after treatment with hydrogen peroxide. Yet an initial upstream analysis of the pathway revealed no significant increase in the level of IκBα inhibitor protein in the unstable clones. Downstream tests analyzing the induction of the antiapoptotic target protein Bcl‐2 found variable induction among the stable and unstable clones. These differences did not translate to a reduction in clonogenic survival after acute exposure to oxidative stress, as the irradiated but chromosomally stable clone displayed the most sensitivity. Due to its role in regulating a diverse set of cellular functions, including responses to oxidative stress, alterations in the NF‐κB pathway in chromosomally unstable clones may regulate the differential physiology of a subset of chromosomally unstable clones and could contribute to the perpetuation of the phenotype. However, a specific role for defective induction and activation of this pathway remains unidentified. Environ. Mol. Mutagen., 2005. © 2005 Wiley‐Liss, Inc.
Screening for large mutations of the NF2 gene
Authors: Kluwe Lan , Nygren Anders O.H. , Errami Abdellatif , Heinrich Bianca , Matthies Cordula , Tatagiba Marcos , Mautner Victor 
Published: January 2005

AbstractNeurofibromatosis 2 (NF2) is a genetic disorder caused by mutational inactivation of the NF2 gene and is characterized by bilateral vestibular schwannomas, spinal tumors, and other benign tumors of the nervous system. Previously, we found intragenic NF2 mutations in 99 of 188 unrelated NF2 patients by exon‐scanning‐based methods. Tumor analysis of 22 de novo NF2 patients led to the identification of 12 additional constitutive NF2 mutations. The remaining 77 patients were further examined for large alterations using the newly developed gene dosage assay multiplex ligation–dependent probe amplification (MLPA). One deletion of a single exon, seven deletions of multiple exons, seven deletions involving the 3′ or 5′ end of the NF2 gene, four deletions involving the whole NF2 gene, and one duplication of three exons were detected. For 47 of the 77 patients, mRNA of adequate quality could be obtained, enabling transcript analysis, which confirmed eight alterations detected by MLPA. In addition, in one family, the mRNA analysis detected an insertion of two exons of another gene. Thus, deletions, duplications, and insertions affecting the NF2 gene were found in 21 cases, which is 11% of the 188 unrelated NF2 patients studied, 16% of the 132 mutations identified, and 27% of the 77 cases in which no intragenic small mutations were detected by exon scanning. The combination of multiple screening techniques facilitated a mutation‐detection rate of 100% for the 21 inherited cases in this study. © 2005 Wiley‐Liss, Inc.
Statistical behavior of complex cancer karyotypes
Authors: Höglund Mattias , Frigyesi Attila , Säll Torbjörn , Gisselsson David , Mitelman Felix 
Published: January 2005

AbstractEpithelial tumors commonly show complex and variable karyotypes that obscure the identification of general patterns of the karyotypic evolution. To overcome some of these problems, we previously systematically analyzed the accumulated cytogenetic data from individual tumor types by using various statistical means. In the present study, we compare previous results obtained for nine tumor types and perform several meta‐analyses of data obtained from a number of epithelial tumors, including head and neck, kidney, bladder, breast, colorectal, ovarian, and lung cancer, as well as from malignant melanoma and Wilms tumor, with the specific aim of discovering common patterns of karyotypic evolution. We show that these tumors frequently develop through a hypo‐ or a hyperdiploid pathway and progress by an increasing number of alternative imbalances through at least two karyotypic phases, Phases I and II, and possibly through a third, Phase III. During Phase I, the karyotypes exhibited a power law distribution of both the number of changes per tumor and the frequency distribution at which bands were involved in breaks. At the transition from Phase I to Phase II/III, the observed power law distributions were lost, indicating a transition from an ordered and highly structured process to a disordered and chaotic pattern. The change in karyotypic orderliness at the transition from Phase I to Phase II/III was also shown by a drastic difference in karyotypic entropy. © 2005 Wiley‐Liss, Inc.
Centromeric breakage and highly rearranged chromosome derivatives associated with mutations of TP53 are common in therapy‐related MDS and AML after therapy with alkylating agents: An M‐FISH study
Authors: Andersen Mette K. , Christiansen Debes H. , Pedersen‐Bjergaard Jens 
Published: January 2005

AbstractMulticolor fluorescence in situ hybridization (M‐FISH) was performed on bone marrow cells of 116 unselected cases of therapy‐related myelodysplasia (t‐MDS) or acute myeloid leukemia (t‐AML), and the results were compared with those of previously performed with G‐banding. Among 18 patients with a normal karyotype, no cryptic chromosome aberrations were observed with M‐FISH. In 56 patients with a previously solved abnormal karyotype, only 17 new aberrations were identified, whereas 153 new aberrations were detected by M‐FISH in 42 patients with a previously unsolved karyotype. In total, 112 of the new aberrations were unbalanced translocations, and only nine were balanced translocations. A clustering of breakpoints was observed in the centromeric or pericentromeric region of chromosomes 1, 5, 7, 13, 17, 21, and 22 in 48 of 98 patients with t‐MDS and t‐AML and an abnormal karyotype, and was related to previous therapy with alkylating agents. In seven of eight patients with chromosome derivatives containing material from three or more chromosomes or having sandwichlike chromosomes, those made up of several small interchanging layers of material from two chromosomes showed mutations of TP53. M‐FISH had little impact on the prognostic classification of t‐MDS and t‐AML, as only three patients changed prognostic groups as a result of M‐FISH. © 2005 Wiley‐Liss, Inc.
Location of Myc, Igh, and Igk on Robertsonian fusion chromosomes is inconsequential for Myc translocations and plasmacytoma development in mice, but Rb(6.15)‐carrying tumors prefer Igk–Myc inversions over translocations
Authors: Silva Santiago , Wiener Francis , Klein George , Janz Siegfried 
Published: January 2005

AbstractThe location of the Myc and immunoglobulin (Ig) loci on metacentric Robertsonian (Rb) fusion chromosomes may affect the development of mouse plasmacytomas (Pcts) by changing the probability with which chromosomal Myc–Ig translocations occur. To test this hypothesis, we induced Pcts in BALB/c (C) mice that carried Rb(4.12) and/or Rb(6.15) chromosomes. The Rb mice developed Pcts (n = 198) with similar onset and incidence to that in the inbred C mice. Karyotyping of 70 Rb–carrying Pcts demonstrated that in these tumors, just as in their counterparts in inbred C mice, the Igh heavy‐chain locus was translocated with Myc more often than was the Igk light‐chain locus. Pcts harboring Igh or Igk on normal and Rb chromosomes showed no bias toward either in generating Myc translocations. These findings indicated that the location of Myc, Igh, and Igk on normal or Rb chromosomes is inconsequential for Myc translocation and Pct development. In contrast, in Rb(6.15) mice, in which chromosomal inversions competed with chromosomal translocations for Igk–Myc juxtapositions, the former occurred more frequently than the latter in the resulting Pcts. This suggested that spatial proximity of Igk and Myc on the same chromosome facilitates the rearrangement of these loci. Myc translocation–dependent mouse Pct may provide a good model system for furthering our understanding of the relationship of higher‐order genome organization in the interphase nucleus, origin of chromosomal translocations, and development of cancer. Published 2005 Wiley‐Liss, Inc.
A cross‐linker‐sensitive myeloid leukemia cell line from a 2‐year‐old boy with severe Fanconi anemia and biallelic FANCD1/BRCA2 mutations
Authors: Meyer Stefan , Fergusson William D. , Oostra Anneke B. , Medhurst Annette L. , Waisfisz Quinten , de Winter Johan P. , Chen Fei , Carr Trevor F. , Clayton‐Smith Jill , Clancy Tara , Green Mike , Barber Lisa , Eden Osborn B. , Will Andrew M. , Joenje Hans , Taylor G. Malcolm 
Published: January 2005

AbstractFanconi anemia (FA) is a rare autosomal recessive disorder characterized by congenital and developmental abnormalities, hypersensitivity to DNA cross‐linking agents such as mitomycin C (MMC), and strong predisposition to acute myeloid leukemia (AML). In this article, we describe clinical and molecular findings in a boy with a severe FA phenotype who developed AML by the age of 2. Although he lacked a strong family history of cancer, he was subsequently shown to carry biallelic mutations in the FANCD1/BRCA2 gene. These included an IVS7 splice‐site mutation, which is strongly associated with early AML in homozygous or compound heterozygous carrier status in FA‐D1 patients. Myeloid leukemia cells from this patient have been maintained in culture for more than 1 year and have been designated as the SB1690CB cell line. Growth of SB1690CB is dependent on granulocyte macrophage colony stimulating factor or interleukin‐3. This cell line has retained its MMC sensitivity and has undergone further spontaneous changes in the spectrum of cytogenetic aberrations compared with the primary leukemia. This is the second AML cell line derived from an FA‐D1 patient and the first proof that malignant clones arising in FA patients can retain inherited MMC sensitivity. As FA‐derived malignancies are normally not very responsive to treatment, this implies there are important mechanisms of acquiring correction of the cellular FA phenotype that would explain the poor chemoresponsiveness observed in FA‐associated malignancies and might also play a role in the initiation and progression of cancer in the general population. © 2005 Wiley‐Liss, Inc.
Identification of differentially expressed genes in oral squamous cell carcinoma (OSCC): Overexpression of NPM, CDK1 and NDRG1 and underexpression of CHES1
Authors: Chang Joseph T. , Wang Hung‐Ming , Chang Ku‐Wei , Chen Wen‐Ho , Wen Ming‐Chun , Hsu Yuan‐Ming , Yung Benjamin Yat‐Ming , Chen I‐How , Liao Chun‐Ta , Hsieh Ling‐Ling , Cheng Ann‐Joy 
Published: January 2005

AbstractTo identify cellular genes that could potentially serve as predictive molecular markers for human oral cancer, we employed differential display analysis to compare the gene expression profiles between oral squamous cell carcinoma (OSCC) and histopathologically normal epithelium tissues. Comparative real‐time RT‐PCR was used to confirm the gene expression in 52 OSCC patients, and a 2‐fold difference was defined as over‐ or underexpression. A total of 7 genes were identified: NPM, CDK1, NDRG1, HMGCR, EF1A, NAC and CHES1. In the cancer tissues, NPM, CDK1 and NDRG1 were significantly overexpressed (an average of 7.6‐, 17.2‐ and 12.9‐fold, respectively), and CHES1 was underexpressed (15‐fold). The frequencies of the differential expression were 40, 56, 67 and 46%, respectively in NPM, CDK1, NDRG1 and CHES1. In Western blot analysis, the protein expressions of NPM, CDK1 and NDRG1 were also increased in the cancer tissues, consistent with the mRNA expression results. To further evaluate clinicopathological associations in these genes, Pearson chi‐square analysis was employed. Levels of CDK1 and NDRG1 were associated with poorly differentiated tumors (p = 0.043 and 0.023), suggesting that these genes participate in the mechanism of tumor transformation. Expressions of CDK1 and NDRG1, and CDK1 and CHES1 were mutually statistically correlated (p = 0.001 and 0.014), indicating that these genes share a very close regulatory relationship or interact synergistically in oncogenesis. In conclusion, we identified 7 genes that are differentially expressed in OSCC, and we provide the first evidence that NPM, CDK1 and NDRG1 are overexpressed and CHES1 is underexpressed in oral cancer. These results serve as a fundamental base for employing these genes in future clinical applications. © 2004 Wiley‐Liss, Inc.
Transcriptional profiling on chromosome 19p indicated frequent downregulation of ACP5 expression in hepatocellular carcinoma
Authors: Chan Kathy Y.‐Y. , Wong Nathalie , Lai Paul B.‐S. , Squire Jeremy A. , Macgregor Pascale F. , Beheshti Ben , Albert Monique , To Ka‐Fai , Johnson Philip J. 
Published: January 2005

AbstractChromosomal rearrangements unraveled by spectral karyotyping (SKY) indicated frequent chromosome 19 translocations in hepatocellular carcinoma (HCC). In an effort to characterize the aberrant 19 rearrangements in HCC, we performed positional mapping by fluorescence in‐situ hybridization (FISH) in 10 HCC cell lines. SKY analysis indicated structural rearrangements of chromosome 19 in 6 cell lines, 4 of which demonstrated recurring 19p translocations with different partner chromosomes. Using fluorescence‐labeled BAC probes, physical mapping indicated a breakpoint cluster between 19p13.12 and 19p12. A corresponding transcriptional mapping by cDNA array on 19p suggested the differential expression of a single downregulated gene ACP5 (tartrate‐resistant acid phosphatase type 5). Quantitative RT‐PCR confirmed the reduced expression of ACP5 and indicated a strong correlation of its repressed expression only in cell lines that contain a 19p rearrangement (p = 0.004). We further examined the expression of ACP5 in a cohort of 82 primary tumors and 74 matching nonmalignant liver tissues. In the primary HCC examined, a reduction of ACP5 transcripts by 2 to as much as 1,000‐fold was suggested in 67% of tumors (55/82 cases). When compared to adjacent nonmalignant tissues, 46% of tumors (34/74 cases) demonstrated a lower expression level (p = 0.015). On closer examination, a high significance of ACP5 repression was suggested in the cirrhotic HCC subgroup that was derived from chronic hepatitis B infected patients (55%; 30/54 cases; p = 0.001). Functional examination of ACP5 ectopic expression in HCC cells further demonstrated a significant growth inhibitory effect of ACP5 on tumor cell survival (p < 0.001). In our study, the novel finding of common ACP5 downregulation in HCC may provide basis for further investigations on the role of acid phosphatase in hepatocarcinogenesis. © 2004 Wiley‐Liss, Inc.
Residential radon exposure, diet and lung cancer: A case‐control study in a Mediterranean region
Authors: Bochicchio Francesco , Forastiere Francesco , Farchi Sara , Quarto Maria , Axelson Olav 
Published: January 2005

AbstractWe performed a case‐control study in Lazio, a region in central Italy characterized by high levels of indoor radon, Mediterranean climate and diet. Cases (384) and controls (404) aged 35–90 years were recruited in the hospital. Detailed information regarding smoking, diet and other risk factors were collected by direct interview. Residential history during the 30‐year period ending 5 years before enrolment was ascertained. In each dwelling, radon detectors were placed in both the main bedroom and the living room for 2 consecutive 6‐month periods. We computed odds ratios (ORs) and 95% confidence intervals (CIs) for time‐weighted radon concentrations using both categorical and continuous unconditional logistic regression analysis and adjusting for smoking, diet and other variables. Radon measurements were available from 89% and 91% of the time period for cases and controls, respectively. The adjusted ORs were 1.30 (1.03–1.64), 1.48 (1.08–2.02), 1.49 (0.82–2.71) and 2.89 (0.45–18.6) for 50–99, 100–199, 200–399 and 400+ Bq/m3, respectively, compared with 0−49 Bq/m3 (OR = 1; 0.56–1.79). The excess odds ratio (EOR) per 100 Bq/m3 was 0.14 (−0.11, 0.46) for all subjects, 0.24 (−0.09, 0.70) for subjects with complete radon measurements and 0.30 (−0.08, 0.82) for subjects who had lived in 1 or 2 dwellings. There was a tendency of higher risk estimates among subjects with low‐medium consumption of dietary antioxidants (EOR = 0.32; −0.19, 1.16) and for adenocarcinoma, small cell and epidermoid cancers. This study indicates an association, although generally not statistically significant, between residential radon and lung cancer with both categorical and continuous analyses. Subjects with presumably lower uncertainty in the exposure assessment showed a higher risk. Dietary antioxidants may act as an effect modifier. © 2004 Wiley‐Liss, Inc.