bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phosphonium Acesulfamate Based Ionic Liquids
Authors: Pernak Juliusz , Stefaniak Filip , Węglewski Józef 
Published: February 2005

AbstractWe present a new class of solvents containing nonfluorous, well‐established, nontoxic organoanions that can be used as “green” alternatives to volatile organic solvents in a variety of applications such as solvent extraction, antielectrostatic agents, and as electrolytes in solar‐cell applications. The acesulfamate anion is an effective substitute for very expensive bis(trifluoromethylsulfonyl)imide (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Practical P‐Chiral Phosphane Ligand for Rh‐Catalyzed Asymmetric Hydrogenation
Authors: Liu Duan , Zhang Xumu 
Published: February 2005

AbstractA highly electron‐donating and conformationally rigid P‐chiral bis(trialkylphospholane) ligand 2 (DuanPhos) has been prepared in both enantiomeric forms through a concise syn‐thesis. Rh‐2 complex has exhibited remarkably high enantio‐selectivities (up to >99% ee) and reactivities (up to 10,000 TON) for the hydrogenation of a wide variety of functionalized prochiral alkenes (5 different types), which provides a very practical catalytic system for the preparation of various synthetically useful chiral compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
A substantial proportion of microsatellite‐unstable colon tumors carry TP53 mutations while not showing chromosomal instability
Authors: Westra Jantine L. , Boven Ludolf G. , van der Vlies Pieter , Faber Hendrika , Sikkema Birgit , Schaapveld Michael , Dijkhuizen Trijnie , Hollema Harry , Buys Charles H. C. M. , Plukker John T. M. , Kok Klaas , Hofstra Robert M. W. 
Published: February 2005

AbstractChromosomal instability in colon tumors implies the presence of numerical and structural chromosome aberrations and is further characterized by the absence of microsatellite instability and the occurrence of KRAS and/or TP53 mutations. In a previous screening of 194 colon tumors for both microsatellite instability and TP53 mutation, we found 25 microsatellite‐unstable tumors, in 9 (36%) of which, presumed to be chromosomally stable, there were TP53 mutations. This prompted us to investigate whether a TP53 mutation in these microsatellite‐unstable tumors would be an indicator of chromosomal instability, that is, whether this would be a category of tumors showing both microsatellite and chromosomal instability. For chromosomal instability assessment, we performed array‐comparative genomic hybridization analysis of tumor and control DNA extracted from formalin‐fixed, paraffin‐embedded stage III colon tumor specimens. The array consisted of 435 subtelomere‐specific BACs. We compared all but one (whose DNA was of bad quality) of the microsatellite‐unstable TP53 mutation‐containing tumors (8) with a similarly sized group of microsatellite‐unstable tumors without TP53 mutation (11). Microsatellite‐unstable tumors with a TP53 mutation showed on average 0.9 aberrations (range 0–3) when assessed with this array system. Those without a TP53 mutation showed on average 0.7 aberrations (range 0–2). Thus, microsatellite‐unstable tumors showed few chromosomal abnormalities regardless of TP53 mutation status. Because, in our study, the microsatellite‐stable tumors had on average 3.4chromosomal abnormalities (range 0–7), a clear difference exists between microsatellite‐unstable and ‐stable tumors. Because a substantial proportion of microsatellite‐unstable colon tumors carry a TP53 mutation while showing relativelyfewchromosomal aberrations, a TP53 mutation in these tumors cannot be considered to be an indicator of chromosomal instability. © 2005 Wiley‐Liss, Inc.
Evolutionary‐based grouping of haplotypes in association analysis
Authors: Tzeng Jung‐Ying 
Published: February 2005

AbstractHaplotypes incorporate more information about the underlying polymorphisms than do genotypes for individual SNPs, and are considered as a more informative format of data in association analysis. To model haplotypes requires high degrees of freedom, which could decrease power and limit a model's capacity to incorporate other complex effects, such as gene‐gene interactions. Even within haplotype blocks, high degrees of freedom are still a concern unless one chooses to discard rare haplotypes. To increase the efficiency and power of haplotype analysis, we adapt the evolutionary concepts of cladistic analyses and propose a grouping algorithm to cluster rare haplotypes to the corresponding ancestral haplotypes. The algorithm determines the cluster bases by preserving common haplotypes using a criterion built on the Shannon information content. Each haplotype is then assigned to its appropriate clusters probabilistically according to the cladistic relationship. Through this algorithm, we perform association analysis based on groups of haplotypes. Simulation results indicate power increases for performing tests on the haplotype clusters when compared to tests using original haplotypes or the truncated haplotype distribution. Genet. Epidemiol. © 2005 Wiley‐Liss, Inc.
Family history of cancer and risk of second malignancies in young cancer patients in Trieste, Italy
Authors: Brunetti Davide , Tamaro Paolo , Fanin Renato , Cavallieri Furio , Stanta Giorgio 
Published: February 2005

AbstractWe carried out a cohort study in the Italian province of Trieste (2001 population, 242,000) to ascertain whether the risk of a subsequent primary cancer among 265 individuals diagnosed with a first malignancy at ages up to 25 years between 1971 and 1993 differed from that in the general population and to evaluate the effect of cancer family history, quantified by the family risk index (FRI), on the occurrence of second primaries. During the follow‐up (median duration = 10 years; 25th–75th percentile = 2–16), 15 cohort members developed a second cancervs. 1.60 expected for a standardized incidence ratio (SIR) of 9.4 (p< 0.0001). The overall SIR fell to 4.7 (p= 0.004) after excluding the 8 patients with well‐known cancer‐predisposing conditions (SIR = 300.0;p< 0.0001) and the 50 with a positive family history (FRI ≥ 1.0) of malignant tumors (SIR = 20.0;p< 0.0001). Among 114 patients treated with radiotherapy and chemotherapy for their first neoplasms and not affected by predisposing disorders, 23 with a positive family history of cancer showed a 6.4‐fold excess risk of second primaries (p= 0.008) compared with 91 with a negative history (FRI < 1.0). It is imperative that clinicians carefully and regularly evaluate cancer family history of young patients with malignancies. This would enable them to identify possible individual and familial features in patients at higher risk of multiple primaries and to adopt more suitable preventive and therapeutic measures. © 2005 Wiley‐Liss, Inc.
Real‐time RT‐PCR detection of CK19, CK7 and MUC1 mRNA for diagnosis of lymph node micrometastases in non small cell lung carcinoma
Authors: Saintigny Pierre , Coulon Séverine , Kambouchner Marianne , Ricci Sylvie , Martinot Emmanuel , Danel Claire , Breau Jean‐Luc , Bernaudin Jean‐François 
Published: February 2005

AbstractMetastatic lymph nodes (LNs) are the major prognostic factor in resected non small cell lung carcinoma (NSCLC). However, almost 50% of pN0 patients relapse, suggesting metastatic cells undetected by current staging procedures. A combination of markers [cytokeratins 19 and 7 (CK19, CK7) and mucin type 1 (MUC1) mRNAs] was therefore evaluated by real‐time RT‐PCR in order to detect occult cancer cells. Forty‐three NSCLC tumor samples, 4 micrometastatic, 6 metastatic and 84 histologically negative mediastinal LNs from 19 patients with NSCLC were evaluated as well as blood mononuclear cells from 29 healthy volunteers and 17 benign LNs. When tested on cell lines, RT‐PCR was particularly efficient for evaluation of CK19, CK7 and MUC1 mRNA expression. All tumor samples were positive for at least 1 marker and 74% of samples were positive for all 3 markers. CK7 and CK19 mRNA were not detected in benign LN and blood cells from healthy donors in contrast with MUC1 mRNA. Only CK7 and CK19 mRNA were therefore used for evaluation of mediastinal LNs: the 6 histologically metastatic and the 4 micrometastatic LNs were positive for at least one marker. Among the 84 histologically negative LNs, 6 (7%) were positive for at least one marker, potentially changing the stage of 2 out of 19 patients. In conclusion, in our feasibility study, parallel molecular detection of CK19 and CK7 mRNA can be considered a specific diagnostic tool for the assessment of microscopic lymphatic spread. Its prognostic impact remains to be evaluated in a prospective study. © 2005 Wiley‐Liss, Inc.
Metalloproteinases and their inhibitors in tumor angiogenesis
Authors: Handsley Madeleine M. , Edwards Dylan R. 
Published: February 2005

AbstractAngiogenesis is the process by which new blood vessels are formed from preexisting vasculature. It is an essential feature of the female reproductive cycle, embryonic development and wound repair. Angiogenesis has also been identified as a causal or contributing factor in several pathologies, including cancer, where it is a rate‐limiting step during tumor progression. Matrix metalloproteinases (MMPs) are a family of soluble and membrane‐anchored proteolytic enzymes that can degrade components of the extracellular matrix (ECM) as well as a growing number of modulators of cell function. Several of the MMPs, in particular the gelatinases and membrane‐type 1 MMP (MT1‐MMP), have been linked to angiogenesis. Potential roles for these proteases during the angiogenic process include degradation of the basement membrane and perivascular ECM components, unmasking of cryptic biologically relevant sites in ECM components, modulation of angiogenic factors and production of endogenous angiogenic inhibitors. This review brings together what is currently known about the functions of the MMPs and the closely related ADAM (a
disintegrin and metalloproteinase domain) and ADAMTS (a
disintegrin and metalloproteinase with thrombospondin motifs) families in angiogenesis and considers how this information might be useful in manipulation of the angiogenic process, with a view to constraining tumor progression. © 2005 Wiley‐Liss, Inc.
Nasopharyngeal carcinoma–susceptibility locus is localized to a 132 kb segment containing HLA‐A using high‐resolution microsatellite mapping
Authors: Lu Cheng‐Chan , Chen Jung‐Chin , Tsai Sen‐Tien , Jin Ying‐Tai , Tsai Jui‐Chen , Chan Shih‐Huang , Su Ih‐Jen 
Published: February 2005

AbstractNasopharyngeal carcinoma (NPC) is an epithelial tumor uniquely prevalent in southern Chinese. HLA‐A2 is associated with NPC. In a previous study, we showed that the genes associated with susceptibility to NPC are primarily located within the HLA‐A locus in Taiwanese NPC patients. However, the pathogenic genes causing NPC susceptibility remain unknown. Here, 8 polymorphic microsatellite markers distributed over a 1 megabase region surrounding the HLA‐A locus were subjected to genetic analysis for the NPC‐susceptibility locus. Statistical studies of associated alleles detected on each microsatellite locus showed that the NPC‐ susceptibility genes are most likely located between the D6S510 and D6S211 markers within a 132 kb segment containing the HLA‐A locus. These results undoubtedly would facilitate the further positional cloning of the NPC‐susceptibility locus, which has been elusive for the past 30 years. © 2005 Wiley‐Liss, Inc.
Na+/H+ exchanger activity is increased in doxorubicin‐resistant human colon cancer cells and its modulation modifies the sensitivity of the cells to doxorubicin
Authors: Miraglia Erica , Viarisio Daniele , Riganti Chiara , Costamagna Costanzo , Ghigo Dario , Bosia Amalia 
Published: February 2005

AbstractMultidrug resistant (MDR) tumor cells exhibit an altered pH gradient across different cell compartments, which favors a reduced intracellular accumulation of antineoplastic drugs and a decreased therapeutic effect. In our study, we have observed that the activity and expression of Na+/H+ exchanger (NHE), which is involved in the homeostasis of intracellular pH (pHi), are increased in doxorubicin‐resistant (HT29‐dx) human colon carcinoma cells in comparison with doxorubicin‐sensitive HT29 cells. The pHi was significantly higher in HT29‐dx cells, which accumulated less doxorubicin than HT29 cells. The NHE inhibitor 5‐(N‐ethyl‐N‐isopropyl)amiloride (EIPA) significantly reduced the pHi value and increased the intracellular accumulation of doxorubicin in both cell populations: in the presence of EIPA HT29‐dx cells accumulated as much drug as control HT29 cells. On the other hand, monensin, a Na+/H+ ionophore mimicking NHE activation, and phorbol 12‐myristate 13‐acetate (PMA), which stimulates NHE, significantly increased the pHi and decreased the drug accumulation in HT29 cells to values similar to those observed in control HT29‐dx cells. EIPA potentiated the cytotoxic effect of doxorubicin in HT29 cells, and made HT29‐dx cells as sensitive to the cytotoxic effect of the drug as control HT29 cells. Instead, PMA and monensin made HT29 cells as insensitive to doxorubicin as HT29‐dx cells. These results suggest that in MDR cells the higher cytosolic pH is likely to decrease drug accumulation, and that such resistance can be reverted by inhibiting the NHE activity. This result opens the possibility to revert MDR with the clinical use of NHE inhibitors. © 2005 Wiley‐Liss, Inc.
Retinoid‐related molecule AGN193198 potently induces G2M arrest and apoptosis in bladder cancer cells
Authors: Reitmair Armin , Shurland Dixie‐Lee , Tsang Kwok‐Yin , Chandraratna Roshantha A.S. , Brown Geoffrey 
Published: February 2005

AbstractThe novel synthetic retinoid‐related molecule 4‐[3‐(1‐heptyl‐4,4‐dimethyl‐2‐oxo‐1,2,3,4‐tetrahydroquinolin‐6‐yl)‐3‐oxo‐propenyl]benzoic acid (AGN193198) neither binds effectively to retinoic acid receptors (RARs) and retinoid X receptors (RXRs) nor transactivates in RAR‐ and RXR‐mediated reporter assays. Even so, AGN193198 is potent in inducing apoptosis in human prostate and breast carcinoma cells (Keedwell et al., Cancer Res 2004;64:3302–12). Here, we extend these findings to show that AGN193198 potently and rapidly induces apoptosis in bladder carcinoma cell lines. One micromolar of AGN193198 completely abolished the growth of the transitional cell carcinoma lines UM‐UC‐3 and J82, and the squamous cell carcinoma line SCaBER; the transitional cell papilloma line RT‐4 was slightly less sensitive to the growth inhibitory effect of AGN193198. Treated cells accumulated in the G2M phase of the cell cycle. This was accompanied by apoptosis, as revealed by staining cells for exposure of phosphatidylserine at their surface (binding of Annexin V) and FACS analysis of propidium iodide labeled cells. As reported for prostate cancer cells, AGN193198 provoked rapid activation of caspases‐3 (by 6 hr), ‐8 (by 16 hr) and ‐9 (by 6 hr) in bladder cancer cells. These findings suggest that AGN193198 and related compounds, whose mechanism of action does not appear to involve RARs and RXRs, may be useful in the treatment of bladder cancer. © 2005 Wiley‐Liss, Inc.
The behavior of transition metal nitrido bonds towards protonation rationalized by means of localized bonding schemes and their weights
Authors: Bachler Vinzenz 
Published: February 2005

AbstractA new computational scheme is applied to rationalize the different protonation behaviors of the nitrido complexes [L′MnV(N)(acac)]+, [LCrV(N)(acac)]+, and [LVV(N)(acac)]+. L and L′ represent the macrocycles 1,4,7‐triazacyclononane and its N‐methylated derivative, respectively, and acac is the bidentate monoanion pentane‐2,4‐dionate. The bonds of the complexes are partitioned into bonds to be investigated and bonds of lesser interest. The investigated bonds are the transition metal nitrido bonds MVN| (M = Mn, Cr, and V) and the bonds of lesser interest are located in the ligands. The ligand bonds are described by means of the strongly occupied natural bond orbitals. The electrons in the MVN| nitrido bonds, however, are treated more accurately. A full configuration interaction procedure is applied in the space spanned by the strongly occupied natural bond orbitals and their corresponding antibonding orbitals. Localized bonding schemes and their weights are obtained for the dπ‐pπ bonds of interest. This is achieved by representing the two‐center natural bond orbitals for a dπ‐pπ bond by the one‐center natural hybrid orbitals localized at the bond atoms. The obtained bonding schemes are close to orthogonal valence bond structures. Their weights indicate that the nitrido nitrogen in [LVV(N)(acac)]+ is more easily protonated than the nitrido nitrogens in [L′MnV(N)(acac)]+ and [LCrV(N)(acac)]+. This result is in good accord with experiment. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 532–551, 2005
Polymorphism of a long‐chain cycloparaffin (CH2)120
Authors: Ihn Kyo Jin , Tsuji Masaki , Kawaguchi Akiyoshi , Katayama Ken‐Ichi 
Published: February 2005

AbstractThe polymorphism of a long‐chain cycloparaffin (CH2)120 and chain packing in its crystals were discussed on the basis of some results obtained mainly by transmission electron microscopy. Monoclinic and orthorhombic single crystals of (CH2)120 were isothermally grown together from a dilute solution in p‐xylene. Lozenge‐shaped orthorhombic single crystals were more frequently observed than lath‐shaped monoclinic ones. The basal surfaces of orthorhombic and monoclinic single crystal platelets wore decorated with vapor‐deposited polyethylene [PE]. Orthorhombic single crystals of (CH2)120 with the (110) twin boundary and monoclinic ones with the (100) twin boundary were also observed.Rod‐like edge‐on crystals of (CH2)120 were grown from a dilute p‐xylene solution onto the (001) surface of alkali halides. The crystal system of the (CH2)120 edge‐on crystals depended on the kind of substrate. The monoclinic crystal was grown on NaCl, the orthorhombic one on KBr and KC1. The monoclinic form of (CH2)120 edge‐on crystal was transformed to the orthorhombic one by annealing on NaCl. In both monoclinic and orthorhombic edge‐on crystals, the molecular plane determined by two zigzag stems in a molecule of (CH2)120 was parallel to the substrate surface and the molecular axis (crystallographic c‐axis) was perpendicular to the longer side of the rod‐like edge‐on crystals. The sub‐cell dimensions of the stem chains in both forms of (CH2)120 crystals were very similar to those of monoclinic and crthorhombic PE crystals, respectively.
Immunoelectron microscopical distribution of histones H2B and H3 and protamines in the course of mouse spermiogenesis
Authors: Biggiogera Marco , Muller Sylviane , Courtens Jean Luc , Fakan Stanislav , Romanini Maria Gabriella Manfredi 
Published: February 2005

AbstractWe have followed the fine structural distribution of two nucleosomal core histones, H2B and H3, and of protamines in the course of mouse spermiogenesis by means of specific antibodies and ultrastructural immunocytochemistry.Our results demonstrate that the nuclear labeling density of histone H2B decreases during steps 6–8 and then increases again in step 9–10 spermatids, while the labeling for histone H3 is constant throughout this period. In step 12 spermatids, the anti‐H2B antibody labels mainly the central area of the nucleus. The first signs of protamine labeling are present in step 12 spermatids, where the gold grains can be found over the periphery of the nucleus. Later on, protamine labeling constantly increases and, by the end of spermiogenesis, the whole nucleus is labeled.We suggest that the morphological and structural differences between the central area and the periphery of mouse spermatids are, at least partly, due to a difference in the protein moiety associated with DNA. The central area, which is peculiar to the mouse and has been previously considered as a focus of chromatin condensation, represents, however, the last nuclear region containing histones and consequently the last area where the substitution of histones by protamines takes place.
Observation of atomic steps on single crystal surfaces by a commercial scanning electron microscope
Authors: Uchida Yuji , Weinberg Gisela , Lehmpfuhl Gunter 
Published: February 2005

AbstractAtomic steps on (111) and (100) crystal surfaces of Pt were observed using a commercial scanning electron microscope (SEM) in secondary electron mode. By comparing the SEM images and those by reflection electron microscopy (REM), the observed contrast was confirmed to be that from atomic steps on crystal surfaces. The contrast mechanism is briefly discussed. One application of this imaging technique is also shown.
Observation of surfaces by reflection electron holography
Authors: Osakabe Nobuyuki 
Published: February 2005

AbstractReflection electron holography is described as a method to observe sub‐Å surface morphology. Phase shift of a Bragg‐reflected electron wave was measured by means of holographic interferometry using an electron microscope equipped with a field emission electron gun and an electron biprism. A short wavelength of high energy electrons is the essential key to the high vertical sensitivity of this method, since geometrical path differences produced by the surface topography are measured in units of wavelengths in interferometrical measuring. Phase shift at a monoatomic step and the displacement field around a dislocation emerging on the surface were observed.
Section staining for electron microscopy using tannic acid as a mordant: A simple method for visualization of glycogen and collagen
Authors: Afzelius BjöRn A. 
Published: February 2005

AbstractThe possibility that tannic acid and other classical mordants can be used in the electron microscopial section staining technique has been tested. A mordant can be defined as a chemical that combines with both a certain specific tissue component and the staining substance and thereby permits a staining reaction that otherwise will not be obtained. The following features were found to characterize section staining of tannic acid mordanted sections. Tannic acid apparently blocks those sites that normally would be contrasted by uranyl acetate or some other staining compounds. Ribosomes remain unstained. Glycogen particles, on the other hand, were stianed, whereas they are not in non‐mordanted sections. In fact, glycogen was the only cytoplasmic component to be contrasted by the uranyl acetate, and collagen the only extracellular component. Several different section staining solutions gave the same staining patterns of examined cells and tissues. Specificity of the reaction thus seems to depend on the mordant rather than on the heavy atom section stain. Some other tested mordants, which have also been used in the light microscopical technique, did not give any useful new information.