bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphological changes and spatial regulation of diacylglycerol kinase‐ζ, syntrophins, and Rac1 during myoblast fusion
Authors: Abramovici Hanan , Gee Stephen H. 
Published: April 2007

AbstractThe fusion of mononuclear myoblasts into multinucleated myofibers is essential for the formation and growth of skeletal muscle. Myoblast fusion follows a well‐defined sequence of cellular events, from initial recognition and adhesion, to alignment, and finally plasma membrane fusion. These processes depend upon coordinated remodeling of the actin cytoskeleton. Our recent studies suggest diacylglycerol kinase‐zeta (DGK‐ζ), an enzyme that metabolizes diacylglycerol to yield phosphatidic acid, plays an important role in actin reorganization. Here, we investigated whether DGK‐ζ has a role in the fusion of cultured C2C12 myoblasts. We show that DGK‐ζ and syntrophins, scaffold proteins of the dystrophin glycoprotein complex that bind directly to DGK‐ζ, are spatially regulated during fusion. Both proteins accumulated with the GTPase Rac1 at sites where fine filopodia mediate the initial contact between myoblasts. In addition, DGK‐ζ codistributed with the Ca2+‐dependent cell adhesion molecule N‐cadherin at nascent, but not previously established cell contacts. We provide evidence that C2 cells are pulled together at cell‐cell junctions by N‐cadherin‐containing filopodia reminiscent of epithelial adhesion zippers, which guide the advance of lamellipodia from apposing cells. At later times, vesicles with properties of macropinosomes formed close to cell‐cell junctions. Reconstruction of confocal optical sections showed these form dome‐like protrusions from the dorsal surface of contacting cells. Collectively, these results suggest DGK‐ζ and syntrophins play a role at multiple stages of the fusion process. Moreover, our findings provide a potential link between changes in the lipid content of the membrane bilayer and reorganization of the actin cytoskeleton during myoblast fusion. Cell Motil. Cytoskeleton 2007. © 2007 Wiley‐Liss, Inc.
The Drosophila nucleoporin gene nup154 is required for correct microfilament dynamics and cell death during oogenesis
Authors: Riparbelli Maria Giovanna , Gigliotti Silvia , Callaini Giuliano 
Published: April 2007

AbstractThe Drosophila nucleoporin gene nup154 is required in both male and female germline for successful gametogenesis. Mutant flies lack differentiated sperm and lay abnormal eggs. We demonstrated that the egg phenotype was associated with specific alterations of the actin cytoskeleton at different stages of oogenesis. Actually, mutant egg chambers displayed an abnormal organization of both subcortical microfilaments and cytoplasmic actin bundles, that led to defective nurse cell dumping. TUNEL analysis also showed that the dumpless phenotype was associated with delayed apoptosis. The nup154 gene product was localized by conventional immunofluorescence microscopy to the nuclear envelope in a distinct punctuate pattern, characteristic of nuclear pore complex components. TEM analysis revealed that the protein was mainly distributed along filamentous structures that extended radially on the nuclear side of the pore, suggesting that Nup154 could be an integral component of the basket filaments associated with the nuclear pore complexes. We propose that Nup154 is necessary for correct nuclear pore complex functions and that the proper regulation of the actin cytoskeleton dynamics strongly relies upon nuclear pore integrity. Cell Motil. Cytoskeleton 2007. © 2007 Wiley‐Liss, Inc.
Design, Synthesis, and Evaluation of Tripeptidic Promoieties Targeting the Intestinal Peptide Transporter hPEPT1
Authors: Thorn Karina , Andersen Rikke , Christensen Jon , Jakobsen Palle , Nielsen Carsten Uhd , Steffansen Bente , Begtrup Mikael 
Published: April 2007

AbstractThe human intestinal proton coupled di/tri‐peptide transporter hPEPT1 promotes the oral bioavailability of several drug compounds. The strategy behind the present work is that by linking a suitable di‐ or tripeptidic promoiety to a drug substance, by a hydrolysable ester bond, it may give rise to a prodrug that targets hPEPT1. 29 tripeptides were designed based on known structural requirements for substrates binding hPEPT1. Serine, homoserine, or threonine was incorporated in the tripeptide as hydroxy group donors in order for them to be linked to carboxylic drug substances. Optimisation of the promoiety included a study of 14 unnatural tripeptides whose diversity was expressed by VolSurf descriptors. A total of 29 tripeptides was synthesised by solid phase peptide synthesis and a standard Fmoc protocol. The affinity of the tripeptides to hPEPT1 was determined by measuring the inhibition of [14C]Gly‐Sar in mature Caco‐2 cell monolayers which resulted in Ki values ranging from 0.22 to 25 mM or above. Translocation through the intestinal membrane, mediated by hPEPT1, was measured by recording the membrane potential relative to that induced by the known substrate Gly‐Sar. The change in membrane potential is caused by influx of protons due to the co‐transport of substrates and protons by hPEPT1 and is, as such, an indication of translocation. A Ki value of 0.30 mM combined with efficient translocation indicated that H‐Phe‐Ser‐Ala‐OH is a suitable lead promoiety for targeted hPEPT1 prodrug design.
Development of a Method for the Quantification of the Molar Gold Concentration in Tumour Cells Exposed to Gold‐Containing Drugs
Authors: Ott Ingo , Scheffler Heike , Gust Ronald 
Published: April 2007

AbstractThe knowledge of the cellular molar concentration of a drug is an extremely important parameter for the discussion and interpretation of its efficacy and bioavailability. Concerning metal complexes, electrothermal atomic absorption spectroscopy (ETAAS) offers a valuable analytical tool. However, matrix effects often hamper proper quantification of the metal concentration in biological tissues. This paper describes the development of an ETAAS method for the quantification of the molar gold concentration in HT‐29 colon carcinoma cells. ETAAS analytical conditions were optimised and a factor was developed which allows the calculation of the molar cellular gold concentration from the measured gold per cellular biomass value. The method was used to quantify the gold content in HT‐29 cells after exposure to the gold drug auranofin. Results indicated a strong cellular uptake of auranofin (compared to other metal anticancer drugs), which significantly correlated with the antiproliferative effects triggered by this agent.
Hepatic metastasectomy in children
Authors: Su Wendy T. , Rutigliano Daniel N. , Gholizadeh Maryam , Jarnagin William R. , Blumgart Leslie H. , La Quaglia Michael P. 
Published: April 2007

AbstractBACKGROUND.There are little data regarding the safety and efficacy of hepatic metastasectomy for solid tumors in childhood. We reviewed our institutional experience to assess operative mortality and morbidity, technique of resection, local control, and survival in pediatric patients undergoing liver resection for metastases.METHODS.All pediatric patients who underwent hepatic resection for metastatic disease from August 1988 to July 2005 were retrospectively identified and clinical data were collected.RESULTS.Fifteen patients were identified during this period and primary malignancies included neuroblastoma (7), Wilms tumor (3), osteogenic sarcoma (2), malignant gastric epithelial tumor (1), and desmoplastic small round cell tumor (2). Twelve patients underwent anatomical hepatic resections and 3 had wedge resections. There were no intraoperative or postoperative deaths. The 2 postoperative complications included 1 wound infection and 1 bile collection. The median follow‐up after hepatic resection was 1.6 years (0.2–7 years). Three patients remain alive. Eleven patients died of progressive disease; 4 patients suffered local recurrence. One patient died from enterocolitis and sepsis and was without evidence of malignancy at the time of death.CONCLUSIONS.Hepatic metastasectomy in children is feasible and is associated with a low operative mortality and morbidity. In this small group of patients anatomic hepatectomy was associated with better local control compared with wedge resection. Overall prognosis in these patients remains poor and the decision to perform hepatic metastasectomy should be highly selective. Cancer 2007. © 2007 American Cancer Society.
Surveillance endoscopy does not improve survival for patients with local and regional stage colorectal cancer
Authors: Ramsey Scott D. , Howlader Nadia , Etzioni Ruth , Brown Martin L. , Warren Joan L. , Newcomb Polly 
Published: April 2007

AbstractBACKGROUNDEndoscopic surveillance is recommended and widely practiced after definitive treatment for colorectal cancer, yet to the authors' knowledge there is little evidence supporting its benefit. The purpose of the current study was to estimate the impact of endoscopic surveillance on colorectal cancer–specific survival for persons with localized or regional colorectal cancer. The population included Medicare patients (age ≥65 years) who were diagnosed with local or regional stage colorectal cancer between 1986 and 1996.METHODSThe current study was a retrospective case–control study. Cases were defined as those individuals who died of colorectal cancer and controls were defined as those with colorectal cancer who did not die of colorectal cancer; controls were frequency matched to cases. Surveillance was defined as the use of colonoscopy, flexible sigmoidoscopy, or barium enema ≥6 months after diagnosis. Logistic regression was used to control for endoscopic procedure, race, comorbidity index at the time of diagnosis, and types of initial treatments after surgery.RESULTSThe analysis group contained 8130 cases (29%) and 20,079 controls (71%). The average time to first bowel surveillance for those with at least 1 surveillance examination was 15.9 months after the diagnosis (median, 13 months). In the regression analysis, surveillance endoscopy was not found to be associated with improved colorectal cancer–specific survival (odds ratio of 1.01; 95% confidence interval, 0.95‒1.06 [P = 0.85]). Setting the surveillance interval to 12 months and 15 months rather than 6 months after diagnosis did not appear to influence the results.CONCLUSIONSSurveillance endoscopy does not appear to influence colorectal cancer–specific mortality in patients age >65 years who are diagnosed with localized or regional stage colorectal cancer. Cancer 2007. Published 2007 by the American Cancer Society.
Effect of familial history and smoking on common cancer risks in Japan
Authors: Suzuki Takeshi , Matsuo Keitaro , Wakai Kenji , Hiraki Akio , Hirose Kaoru , Sato Shigeki , Ueda Ryuzo , Tajima Kazuo 
Published: April 2007

AbstractBACKGROUNDInherited genetic predispositions are important risk factors for the development of cancer in general. To determine genetic susceptibility for 14 common cancers, a case–control study of the impact of a family history of cancer in first‐degree relatives was conducted. The authors further evaluated the effect modification by habitual smoking with adjustment for other confounding environmental factors.METHODSIn total, 18,836 cancer cases and 28,125 age–matched and sex–matched controls, confirmed as being free of cancer, were recruited. Odds ratios (ORs) and 95% confidence intervals were determined by multiple logistic regression analysis, including stratification by family history for 14 cancer sites and interactions with a smoking history.RESULTSThe associations between family history and risk of cancer were generally stronger at the same sites than across cancer sites. Risks to first‐degree relatives at the same sites were found to be significantly elevated with 8 of 14 cancer sites; especially high ORs were found for prostate and thyroid cancers. Some across‐site associations were observed; in particular, a reciprocal association between breast and prostate cancer was found. The interaction between family history and smoking history for breast cancer was found to be statistically significant. There was no statistical evidence for the interactions in other sites, but among subjects with a family history, the ORs were found to be higher in smokers compared with nonsmokers.CONCLUSIONSThe results of the current study support the hypothesis of a genetic susceptibility to cancers in family members. For breast cancer, the interaction between family history and smoking history was observed to be significant. Cancer 2007. © 2007 American Cancer Society.
Investigations on the crystallisation of potassium molybdenum bronzes from flux melts
Authors: Aichele T. 
Published: April 2007

AbstractResults are presented to identify the fields of primary crystallisation of red and blue potassium molybdenum oxide bronzes K0.30MoO3 and K0.33MoO3 in the ternary system K2MoO4–MoO3–MoO2. Starting from crystal growth experiments for the preparation of bronze crystals by electrolytic reduction the binary marginal systems K2MoO4–MoO3 as well as MoO3–MoO2 and further pseudo‐binary sections have been investigated by differential thermo‐analysis, hot‐stage microscopy, and by quenching experiments under inert gas. We succeeded in determining phase transition temperatures in the binary section Mo4O11–K2Mo2O7. Temperature and composition ranges have been found in this section to crystallise red and blue potassium molybdenum oxide bronzes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determination of nucleation parameters and the solid liquid interfacial energy of the KCl‐ethanol‐water system
Authors: Omar Waid , Ulrich Joachim 
Published: April 2007

AbstractThe kinetic parameters of homogeneous nucleation of KCl in different ethanol‐water solvent mixtures were determined at 25°C from the experimental measurements of the width of the metastable zone at different cooling rates. The ethanol mass ratio in the ethanol water solvent mixture was varied from 0‐0.9 and the metastable zone width for each solvent mixture was measured under the cooling rates of 10, 20 and 30 K/h. The influence of ethanol ratio on the activity coefficient was calculated. It was found that increasing the ethanol ratio in the solvent mixture leads to an increase in the mean molal activity coefficient. The experimental results obtained showed that the increase in the ethanol ratio in the solvent widens the metastable zone for the crystallization of KCl. Also it has inferred from the calculations based on the classical nucleation theory that increasing of the ethanol ratio in the solvent mixture resulted in an increase of the nucleation rate order, increase of the critical size of nuclei and increase of the solid liquid interfacial energy. It has been found that the solid liquid interfacial energy can be good correlated with inversely proportionality to the solubility. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and characterization of a PbI2 single crystal used for gamma ray detectors
Authors: Zhu X. H. , Wei Z. R. , Jin Y. R. , Xiang A. P. 
Published: April 2007

AbstractLead iodide (PbI2) is an important material for room temperature radiation detectors. In this paper, we have grown PbI2 single crystal through a special craft, from which γ‐ray detector has also been fabricated. X‐ray diffraction analysis indicates structure of the grown crystal is 2H with hexagonal space group P3m1. Infrared transmission measurement shows transmission rate of the grown crystal sample (10×10×1mm3) reaches 40% averagely in range of 400∼4000cm‐1. Ultraviolet absorbing test indicates cut‐off wavelength of the sample is 547.6nm, corresponding band gap of 2.27eV. Room temperature detector fabricated from the grown crystal is sensitive to 241Am 59.5KeV γ‐ray. Full width at half maximum (FWHM) of the obtained energy spectrum is 26.7KeV. All the results indicate the PbI2 crystal grown through the special craft is of good characteristics and can be used for γ‐ray detector. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and characterization of L‐prolinium tartrate – A new organic NLO material
Authors: Britto Dhas S. A. Martin , Natarajan S. 
Published: April 2007

AbstractSingle crystals of L‐Prolinium tartrate (C5H10NO2)+ (C4H5O6)‐, a new organic non‐linear optical material of size: 15 × 10 × 10 mm3 were grown using submerged seed solution growth method. Characterization of the crystals was made using single crystal X‐ray diffraction and density determination. Spectroscopic, thermal, optical and mechanical studies were carried out. These studies show that the crystals are thermally stable upto 161°C, transparent for the fundamental and second harmonic generation of Nd: YAG (λ = 1064 nm) laser and possess good mechanical strength. Second harmonic generation (SHG) conversion efficiency was investigated to explore the NLO characteristics of this material using Kurtz and Perry method and it was found that the SHG conversion efficiency is about 90% of that of the standard KDP crystals. Laser damage threshold study was also carried out. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structure and optical properties of near stoichiometric Ce:LiNbO3 crystals
Authors: Fan Yexia , Li Hongtao , Zhao Liangcheng 
Published: April 2007

AbstractThe near sotichiometric Ce:LiNbO3 (Ce:SLN) crystals were grown by the top seeded solution growth (TSSG) method by adding K2O flux to Li2O‐Nb2O5 melt. Their UV‐vis absorption spectra and IR spectra were measured and discussed to investigate their defect structure. The results showed that the grown crystals were near stoichiometric and Ce ions in the crystals located the Li site. Photorefractive properties of Ce:SLN crystals were studied by two‐wave coupling experiment. The results of the two‐wave coupling experiments of the crystals showed that as the CeO2 doping concentrations increased, the diffraction efficiency increased, photoconductivity decreased and the writing time and erasure time increased. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoelectrical properties of crystalline titanium dioxide thin films after thermo‐annealing
Authors: Sathyamoorthy R. , Sudhagar P. , Chandramohan S. , Vijayakumar K. P. 
Published: April 2007

AbstractThis paper reports the photoelectrical properties of sol gel derived titanium dioxide (TiO2) thin films annealed at different temperatures (425‐900°C). The structure of the as‐grown film was found to be amorphous and it transforms to crystalline upon annealing. The trap levels are studied by thermally stimulated current (TSC) measurements. A single trap level with activation energy of 1.5 eV was identified. The steady state and transient photocurrent was measured and the results are discussed on the basis of structural transformation. The photocurrent was found to be maximum for the films annealed at 425°C and further it decreases with annealing at higher temperatures. The photoconduction parameters such as carrier lifetime, lifetime decay constant and photosensitivity were calculated and the results are discussed as a function of annealing temperature. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoconduction and transport mechanisms in polycrystalline zincphthalocyanine thin films
Authors: Senthilarasu S. , Lee S. H. 
Published: April 2007

AbstractZincphthalocyanine (ZnPc) thin films were prepared by the vacuum evaporation method under a pressure of 10‐6 mbar. The X‐ray diffraction analysis of vacuum evaporated ZnPc films reveals that the structure of the films is polycrystalline in nature. The photoconduction properties have been studied in the wavelength range 400 –800nm using suitable masks. The Photoconductivity of the films as a function of light intensity and applied voltage were studied and results were discussed in detail. The photoconduction was found to increase with higher light illumination and maximum at the band edge of the ZnPc thin film. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structure of (dimethyl sulfoxide‐S){glyoxylic acid thiosemicarbazonato(2–)‐O,N,S }platinum(II)
Authors: Dodoff N. I. , Kovala‐Demertzi D. , Kuduk‐Jaworska J. , Kubiak M. , Kochel A. 
Published: April 2007

AbstractA crystal of the title complex [Pt(DMSO)(GT)] (1a), where H2GT = glyoxylic acid thiosemicarbazone, has been characterized by X‐ray crystallography and its structure has been compared with that of the recently described cytotoxic complex [Pt(DMSO)(GT)]·DMSO (1). The crystal of 1a is monoclinic; space group P 21/n; unit cell dimensions: a = 7.3270(10), b = 10.313(2), c = 13.706(3) Å, β = 101.92(3)°; V = 1013.3(3) Å3; Z = 4. The Pt(II) ion is approximately planar tetragonal coordinated by the carboxylato oxygen, azomethine nitrogen and thiolato sulfur atom of the doubly deprotonated H2GT molecule, and the sulfur atom of DMSO. The two five membered chelate rings are almost coplanar. In distinct with 1, the sulfoxide oxygen atom and thiolato sulfur atom are in gauche position. A system of hydrogen bonds of the type N–H···O involving the amino, carboxylato and sulfoxide groups links the complex molecules within the unit cells. The π ‐π stacking pattern between the chelate rings in 1a involves centrosymmetric pairs of complex molecules and differs from that in 1. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Particle‐in‐Cell Simulation of the Breakdown Mechanism in Microdischarges with an Improved Secondary Emission Model
Authors: Radmilović‐Radjenović M. , Radjenović B. 
Published: April 2007

AbstractIn this paper, the failure of the breakdown voltage from the Paschen's law at extremely small electrode separations is studied. The electrical breakdown in microgaps occurs at the voltages far below the Paschen curve minimum breakdown limit and the modified Paschen curve should be used. Offered explanation for the departure from the Paschen's law at small gap spacings is based on the increasing of the yield of the secondary electrons. The high electric fields existing in small gaps may enhance the secondary electron yield and this would lead to a lowering of the breakdown voltage and to the departure from the Paschen's law. Particlein‐cell/Monte‐Carlo (PIC/MCC) simulations with a new secondary emission model have been performed to estimate the importance of this mechanism in the discharge breakdown. Obtained simulation results suggest that deviations from the Paschen curve across the micron and submicorn gap spacing can be attributed to the ion‐enhanced field emissions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrical Conductivities of Nonideal Iron and Nickel Plasmas
Authors: Kim D.‐K. , Kim I. 
Published: April 2007

AbstractElectrical conductivities of iron and nickel plasmas are calculated using a nonideal plasma ionization balance model that takes into account the excess free energy due to strong Coulomb couplings between charged particles in the pressure‐ionization regime. The electrical conductivities calculated for partially ionized plasmas are in fair agreement with data measured in exploding wire discharge experiments and effectively demonstrate the insulator‐metal transition near solid densities. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Atomic Layer Deposition of Titanium Disulfide Thin Films
Authors: Pore V. , Ritala M. , Leskelä M. 
Published: April 2007

AbstractTitanium disulfide thin films are grown by atomic layer deposition (ALD) at 400–500 °C using TiCl4 and H2S as precursors. Soda‐lime glass, silicon, and thin films of TiN, ZnS, Rh, Ir, Pd, Pt, and Ru are used as substrates. Hexagonal (001)‐oriented TiS2 is deposited on ZnS at 400 °C with growth rates of between 0.15 and 0.20 Å per cycle. Randomly oriented, hexagonal, platelike crystals are deposited on glass and TiN with a growth rate of 0.26 Å per cycle. Significant variations in surface morphologies were detected in TiS2 films on various noble metals. TiS2 was also grown on the pore walls of an alumina membrane.