bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discovery of Inhibitors of MCF‐7 Tumor Cell Adhesion to Endothelial Cells and Investigation on their Mode of Action
Authors: Bild Thomas , Jose Joachim , Hartmann Rolf W. 
Published: December 2004

AbstractMetastasis, the main reason for high mortality of cancer, is a multistep process. One important step in this process is the adhesion of tumor cells to vascular endothelium at sites distant from primary tumors during hematogenous dissemination. In order to investigate and quantify the adhesion of tumor cells to endothelial cells we developed an in vitro model using MCF‐7 breast cancer cells and monolayers of human umbilical vein endothelial cells (HUVEC). The tumor cells were specifically labeled with a fluorescent dye for quantification; for increasing the amount of adherent cells, HUVEC monolayers were stimulated with phorbol ester before the addition of the tumor cells. Due to previous reports that products of several P450 enzymes contribute to the progression of certain kinds of cancer, inhibitors of CYP5 (thromboxane A2 synthase), CYP17 (17α‐hydroxylase‐C17, 20‐lyase), and CYP19 (aromatase) were tested in this in vitro model for their potency to reduce cancer cell adhesion. Within each series of P450 inhibitors, compounds with high inhibitory activity on tumor cell adhesion were identified. At an initial concentration of 100 μM, BW26, a potent inhibitor of CYP5, reduced tumor cell adhesion of MCF‐7 to HUVECs to 15 %, BW40 (CYP17) to 29 %, and SU5a (CYP19) to 11 % of the corresponding controls (no inhibitor). Reduction of tumor cell adhesion was shown to occur in a concentration‐dependent manner. In addition to these inhibitors of CYP5, CYP17, and CYP19, liarozole, known to be a potent inhibitor of CYP26 (retinoic acid‐4‐hydroxylase) and ATRA (all‐trans‐retinoic acid) metabolism, was able to reduce tumor cell adhesion to 51 % of the initial rate. Experiments elucidating the mode of action of these compounds revealed that inhibition of the mentioned CYP enzymes is not responsible for their ability to reduce tumor cell adhesion.
Rates and Equilibria of the Reactions of Tertiary Phosphanes and Phosphites with Benzhydrylium Ions
Authors: Kempf Bernhard , Mayr Herbert 
Published: December 2004

AbstractThe kinetics of the reactions of benzhydrylium ions and quinone methides with eight tertiary phosphanes and two phosphites were investigated photometrically. The nucleophilicity parameters N and slope parameters s of these nucleophiles were derived according to the equation log k20 °C = s(N + E). Correlations of the nucleophilicity parameters N with pKHa and σp values as well as with the rate constants of reactions with other electrophiles are discussed. In some cases, equilibrium constants for the formation of phosphonium ions were measured, which allow one to determine the Marcus intrinsic barriers of ΔG0≠ = 58 kJ mol−1 for the reactions of triarylphosphanes with benzhydrylium ions. The N parameters [5.51 for P(OPh)3, 10.36 for P(OBu)3, 14.33 for PPh3, 15.49 for PBu3, 18.39 for P(4‐Me2NC6H4)3] are compared with the reactivities of other classes of nucleophiles (see, www.cup. uni‐muenchen.de/oc/mayr).
Palladium‐Catalyzed Desulfitative Mizoroki–Heck Couplings of Sulfonyl Chlorides with Mono‐ and Disubstituted Olefins: Rhodium‐Catalyzed Desulfitative Heck‐Type Reactions under Phosphine‐ and Base‐Free Conditions
Authors: Dubbaka Srinivas Reddy , Vogel Pierre 
Published: December 2004

AbstractNew conditions have been found for the desulfitative Mizoroki–Heck arylation and trifluoromethylation of mono‐ and disubustituted olefins with arenesulfonyl and trifluoromethanesulfonyl chlorides. Thus (E)‐1,2‐disubstituted alkenes with high stereoselectivity and 1,1,2‐disubstituted alkenes with 12:1 to 21:1 E/Z steroselectivity can be obtained. Herrmann's palladacycle at 0.1 mol % is sufficient to catalyze these reactions, for which electron‐rich or electron‐poor sulfonyl chlorides and alkenes are suitable. If phosphine‐ and base‐free conditions are required, 1 mol % [RhCl(C2H4)2] catalyzes the desulfitative cross‐coupling reactions. Contrary to results reported for [RuCl2(PPh3)2]‐catalyzed coupling reactions with sulfonyl chlorides, the palladium and rhodium desulfitative Mizoroki–Heck coupling reactions are not inhibited by radical scavenging agents. Possible sulfones arising from the sulfonylation of alkenes at 60 °C are not desulfitated at higher temperatures in the presence of the Pd or Rh catalysts.
Short‐term, medium‐term, long‐term, and lifetime risks of developing and dying of breast carcinoma in a Westernized Chinese population
Authors: Leung Gabriel M. , Thach Thuan Q. , Chan Eric , Foo William , Meng Oscar , Fielding Richard , Lam Wendy W. T. , Hedley Anthony J. , Wong Chit‐Ming , Lam Tai‐Hing 
Published: December 2004

AbstractBACKGROUNDEstimates of lifetime and shorter‐term risks of developing and dying of breast carcinoma are useful translational statistics for risk communication; however, these statistics are unknown for Chinese women, who account for one‐fifth of the world's female population. In the current study, the authors examined age‐specific 5‐year, 10‐year, 20‐year, and lifetime risks of breast carcinoma incidence and disease‐related mortality among Hong Kong women.METHODSMultiple‐decrement life tables were constructed by applying age‐specific incidence and mortality rates obtained from cross‐sectional data to a hypothetic birth cohort. Incidence, mortality, and population data from 1976 through 2000 were used.RESULTSFor Hong Kong women in the period 1996–2000, the overall lifetime risk of developing invasive breast carcinoma was 5.7% (1 in 17), compared with 10.6% (1 in 9) for U.S. Asian/Pacific Islander women and 14.5% (1 in 7) for U.S. white women. The lifetime breast carcinoma–related mortality risk for Hong Kong women in that same period was 1.7% (1 in 58). For women age 50 years, the 5‐, 10‐, and 20‐year risks of developing breast carcinoma were 0.6% (1 in 172), 1.1% (1 in 87), and 2.1% (1 in 47), respectively. The absolute lifetime probability of developing breast carcinoma increased from 3.81% (1 in 26) during the period 1976–1980 to 5.73% (1 in 17) during the period 1996–2000; 44.5% of this change can be attributed to the increased longevity of women in the latter time period, and the remaining 55.5% can be ascribed to a secular rise in breast carcinoma incidence.CONCLUSIONSAs China becomes more Westernized, the authors expect that the risks of developing and dying of breast carcinoma for Chinese women will become more similar to the corresponding risks for Western women. The current data from Hong Kong, the most Westernized Chinese community, appear to support this conclusion. Cancer 2005. © 2004 American Cancer Society.
A pilot study of high‐dose intraarterial cisplatin chemotherapy with concomitant accelerated radiotherapy for patients with previously untreated T4 and selected patients with T3N0–N3M0 squamous cell carcinoma of the upper aerodigestive tract
Authors: Foote Robert L. , Kasperbauer Jan L. , Okuno Scott H. , Nichols Douglas A. , Olsen Kerry D. , Brown Paul D. , Garces Yolanda I. , Sargent Daniel J. , Strome Scott E. 
Published: December 2004

AbstractBACKGROUNDThis Phase I clinical trial was developed to assess the feasibility of combining high‐dose intraarterial cisplatin chemotherapy with concurrent, concomitant boost accelerated radiation therapy for patients with previously untreated T4 and select patients with T3N0–N3M0 squamous cell carcinoma of the upper aerodigestive tract.METHODSBetween July 1999, and February 2002, 19 patients were treated with 3 or 4 weekly cycles of intraarterial Cisplatin chemotherapy (150 mg/m2) with concurrent, concomitant boost accelerated radiation therapy (72 grays in 42 fractions over 6 weeks).RESULTSTwo patient deaths occurred among the first 15 patients enrolled. Both patients presented with febrile neutropenia, and both died of complications related to infection. The number of cycles of intraarterial cisplatin was reduced from four cycles to three cycles, and an additional four patients were treated. The fourth patient treated on the modified protocol developed febrile neutropenia, sepsis, and a thromboembolic event, which resulted in lower extremity amputations. The maximum acute toxicity experienced was Grade 2 in 6 patients, Grade 3 in 5 patients, Grade 4 in 6 patients, and Grade 5 in 2 patients. With a median follow‐up of 21 months (range, 6.2–34.6 months), the overall survival at 1 year was 89.5% (95% confidence interval [95%CI], 76.7–100%). At 1 year, 92.9% of the patients were free from disease progression (95%CI, 80.3–100%).CONCLUSIONSThe results of this study suggest that concurrent intraarterial cisplatin chemotherapy at a dose of 150 mg/m2 with concomitant boost accelerated radiation therapy is not feasible. Cancer 2005. © 2004 American Cancer Society.
Monomers, Chains and Layers of [Pt2(SO4)4] Units in the Crystal Structures of the Platinum(III) Sulfates (NH4)2[Pt2(SO4)4(H2O)2], K4[Pt2(SO4)5] and Cs[Pt2(SO4)3(HSO4)]
Authors: Pley Martin , Wickleder Mathias S. 
Published: December 2004

AbstractThe reaction of Pt(NO3)2 with concentrated sulfuric acid in sealed glass ampoules at 400 °C causes reduction of the nitrate ion to NH4+ and leads to single crystals of (NH4)2[Pt2(SO4)4(H2O)2] [triclinic, P$\bar 1$
, Z = 1, a = 749.96(9), b = 754.2(1), c = 765.4(1) pm, α = 102.15 (1)°, β = 110.23(1)°, γ = 100.87(1)°, Rall = 0.0677]. In the crystal structure, Pt2 dumbbells are coordinated by four bidentate‐bridging sulfate ions and two axial H2O molecules. The replacement of the axial H2O molecules with SO42−, which can be observed in the crystal structure of K4[Pt2(SO4)5] [triclinic, P$\bar 1$
, Z = 2, a = 975.6(1), b = 1331.8(1), c = 1491.0(1) pm, α = 101.156(8)°, β = 96.278(8)°, γ = 102.849(8)°, Rall = 0.0459], causes a connection of the dumbbells into chains of the composition 1∞[Pt2(SO4)4/1(SO4)2/2]4−. K4[Pt2(SO4)5] has been obtained from the reaction of K2[PtCl4] and concentrated H2SO4 at 400 °C in sealed glass tubes. The same reaction with Cs2[PtCl4] instead of K2[PtCl4] leads to Cs[Pt2(SO4)3(HSO4)] [monoclinic, P21/c, Z = 4, a = 1724.8(2), b = 881.28(9), c = 935.1(1) pm, β = 100.397(8)°, Rall = 0.0458]. In the crystal structure, part of the bidentate‐bridging sulfate ions of the [Pt2(SO4)4] core act as monodentate ligands to further Pt2 dumbbells leading to anionic layers of the composition 2∞[Pt2(SO4)4/2(SO4)2/1]2− and neutral units with the formula 2∞[Pt2(SO4)4/2(HSO4)2/1]. The two types of layers are stacked alternatingly with the ten coordinate Cs+ ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
The effect of fatty acid composition on biodiesel oxidative stability
Authors: Falk Oliver , Meyer‐Pittroff Roland 
Published: December 2004

AbstractConcerning their environmental impact, native based fuels and lubricants show immense potential. In fact, these products are highly exposed to oxidative processes during storage or application [1, 2]. One way to raise oxidative stabilities is the addition of synthetic antioxidants. Another way may be the modification of the fatty acid composition, since polyunsaturated fatty acids show a much higher proneness to autoxidation. In order to decrease the content of polyunsaturated and to raise the content of saturated components, experiments for fractional distillation and crystallisation as well as for hydrogenation of fatty acid methyl esters have been carried out.In distillation experiments with separation columns the methyl esters performed good separation of the lower‐boiling esters with a chain‐length up to 16C‐atoms, from the C‐18 fraction, causing a degree of saturation up to 75 wt‐% in the distillate. In tests with fractional crystallisation, the rate of saturation could be raised up to 92.8 wt‐%. Using the process of catalytic hydrogenation, a rate of saturation up to 100 wt‐% could be achieved, depending on the duration of the hydrogenation process. By partial hydrogenation of the polyunsaturated components, products with high oxidation stability and low pour point could be produced within relatively short hydrogenation time.
Kinetics of free fatty acids esterification with methanol in the production of biodiesel fuel
Authors: Sendzikiene Egle , Makareviciene Violeta , Janulis Prutenis , Kitrys Saulius 
Published: December 2004

AbstractThe aim of this study was the determination of optimal conditions of free fatty acid esterification by methanol using acid catalyst, and the calculation of the kinetic parameters of this process.It was found that the reaction rate depends on the amount of the catalyst and the acidity of the reaction mixture. The reaction rate changes also depending on the reaction duration, especially during the first 15 min.Establishing the above mentioned parameters proved the effect of the agents on the reaction rate. Such dependence is characteristic to many heterogeneous processes. The data suggest that having excluded diffusion, the reaction order is about 1. Within the limits of the experimental conditions (free fatty acids 0.162 mol//L‐1.948 mol/L, temperature 20–60 °C, constant mixing speed –850 min‐1, 1% of catalyst (H2SO4)) the apparent energy of activation Et is ≈ 13.3 kJ/mol, while pre‐exponent A = 1.27. These parameters allow the assumption that diffusion restrictions are characteristic to the entire range of the concentrations and the reaction duration studied.
Recent progress in the use of soluble ionic polymers as pseudostationary phases for electrokinetic chromatography
Authors: Palmer Christopher P. , McCarney Jonathan P. 
Published: December 2004

AbstractThis review concerns the development, characterization, and application of soluble ionic polymeric materials as pseudostationary phases for electrokinetic chromatography since 2002. Cationic polymers, anionic siloxanes, polymerized surfactants (micelle polymers), and chiral polymers are considered. The use of stable suspensions of polymer nanoparticles in electrokinetic chromatography is also reviewed.
Capillary electrophoresis of inorganic ions: An update
Authors: Timerbaev Andrei R. 
Published: December 2004

AbstractThis review as a sequel of three earlier similar reports gives a summary of the progress and significant methodological developments, starting from 2002, in the use of capillary electrophoresis (CE) for inorganic ion analysis. As substantiated by the illustrative number of relevant references, improvements in sensitivity achieved both in and outside a CE system, advances in manipulating the separation selectivity, novel hardware configurations, and system performance innovations are continually being reported over the review period. Specifically viewed are the recent advancements in elemental (bio)speciation analysis, which remains one of the most fertile areas of CE research, as well as in three recently booming research topics: contactless conductivity detection, separations on microchips, and transient isotachophoretic preconcentration. A state‐of‐the‐art picture of technique's potentialities within the field of interest presented here demonstrates that CE has become recognized and is growing in acceptance as a reliable alternative to traditional analytical methods such as high‐performance liquid chromatography (HPLC).
Capillary electrophoresis‐mass spectrometry: Recent advances to the analysis of small achiral and chiral solutes
Authors: Shamsi Shahab A. , Miller Blair E. 
Published: December 2004

AbstractWe describe here the state‐of‐the‐art development of on‐line capillary electrophoresis‐mass spectrometry (CE‐MS) over the last two years. Technological developments included are novel designs of new interfaces and ionization sources, new capillary coatings, buffers, and micelles as well as application of various modes of CE‐MS published in the recent literature. The areas of CE‐MS application in analysis of small achiral and chiral solutes are covered in sections that highlight the recent advances and possibilities of each mode of CE‐MS. Application areas reviewed in this paper include achiral and chiral pharmaceuticals, agrochemicals, carbohydrates, and small peptides. The separation of enantiomers using micellar electrokinetic chromatography (MEKC)‐MS with molecular micelles and capillary electrochromatography (CEC)‐MS using pack tapered columns appears to provide good tolerance to electrospray stability for routine on‐line CE‐MS. These two modes seem to be very suitable for sensitive detection of chiral pharmaceuticals in biological samples, but their use will probably increase in the near future. Overall, it seems that one mode of CE‐MS, in particular capillary zone electrophoresis (CZE)‐MS, is now recognized as established technique for analysis of small charged solutes, but other modes, such as MEKC‐MS and CEC‐MS, are still within a period of development in terms of both MS‐compatible pseudostationary phases and columns as well as applications.
Conductivity detection for conventional and miniaturised capillary electrophoresis systems
Authors: Guijt Rosanne M. , Evenhuis Christopher J. , Macka Miroslav , Haddad Paul R. 
Published: December 2004

AbstractSince the introduction of capillary electrophoresis (CE), conductivity detection has been an attractive means of detection. No additional chemical properties are required for detection, and no loss in sensitivity is expected when miniaturising the detector to scale with narrow‐bore capillaries or even to the microchip format. Integration of conductivity and CE, however, involves a challenging combination of engineering issues. In conductivity detection the resistance of the solution is most frequently measured in an alternating current (AC) circuit. The influence of capacitors both in series and in parallel with the solution resistance should be minimised during conductivity measurements. For contact conductivity measurements, the positioning and alignment of the detection electrodes is crucial. A contact conductivity detector for CE has been commercially available, but was withdrawn from the market. Microfabrication technology enables integration and precise alignment of electrodes, resulting in the popularity of conductivity detection in microfluidic devices. In contactless conductivity detection, the alignment of the electrodes with respect to the capillary is less crucial. Contactless conductivity detection (CCD) was introduced in capillary CE, and similar electronics have been applied for CCD using planar electrodes in microfluidic devices. A contactless conductivity detector for capillaries has been commercialised recently. In this review, different approaches towards conductivity detection in capillaries and chip‐based CE are discussed. In contrast to previous reviews, the focus of the present review is on the technological developments and challenges in conductivity detection in CE.
Monitoring mountain snowpack evolution using near‐surface optical and thermal properties
Authors: Lampkin Derrick J. , Yool Stephen R. 
Published: December 2004

AbstractWe developed a near‐surface moisture index (NSMI) that models relative moisture using visible and thermal spectra. The NSMI tracks the evolution of spring snowmelt and has potential MODIS applications. An analytical radiative transfer model for computing directional hemispherical reflectance and emissivity derived from the delta‐Eddington approximation to the radiative transfer equation was used to produce the NSMI. Modelled reflectance and emissivity, as a function of grain size, were used to produce the NMSI feature space, constructed from the normalized difference snow index (NDSI) on the abscissa and brightness temperature (Tb) on the ordinate. As grain size increases, the dynamic range (sensitivity) of NDSI decreases, saturating around 400–450 µm grain radius. Tb values for various grain sizes at fixed kinetic temperatures between 245 and 273 K and the NDSI were used to construct a simulated NSMI. Field measurements of surface wetness, surface/near‐surface grain size, average pack temperature and surface temperature for late February and March were validated in Fraser, Colorado, against measured NSMI using a scene from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). Ground‐based measurements indicate significant changes in snow surface properties, representing a warming pack across three Cold Land Processes Experiment (CLPX) intensive study areas (ISAs) from February to March. Surface and average pack temperatures in March were warmer for all three sites. ASTER‐measured reflectance and Tb were sampled from each CLPX ISA and used to construct the NMSI. The lower elevation ISA (i.e. St Louis Creek) demonstrated higher mean Tb and lower mean NDSI, and the higher elevation ISA (i.e. Alpine) showed higher mean NDSI and lower mean Tb. ASTER‐derived NSMI demonstrated behaviour consistent for simulations with deviations due to topography, vegetation, and regional heterogeneity. Copyright © 2004 John Wiley & Sons, Ltd.
Ground‐based frequency‐modulated continuous wave radar measurements in wet and dry snowpacks, Colorado, USA: an analysis and summary of the 2002–03 NASA CLPX data
Authors: Marshall Hans‐Peter , Koh Gary , Forster Richard R. 
Published: December 2004

AbstractGround‐based frequency‐modulated continuous wave (FMCW) radar measurements made throughout the 2002–03 NASA Cold Lands Processes (CLPX) mission in Colorado, USA, were designed to study the major electromagnetic transitions within the alpine snowpack over a wide range of conditions, and their effect on measurements made with different active radar measurement parameters. Measurements during 2002 determined that measurements at C‐, X‐, and Ku‐band frequencies were necessary to retrieve the most snowpack information in a wide range of conditions. Measurements at four different incidence angles indicated that the snowpack layering was still visible at 15° but that the rough surface scattering of the snow–ground interface dominated the signal above 30° incidence. Measurements during 2003 were focused on characterizing the microwave response at C‐, X‐, and Ku‐band frequencies at four different sites with different snowpack conditions, indicating that the optimal measurement parameters vary with snowpack conditions. Measurements at different bandwidths illustrate the effect of bandwidth on vertical resolution. This ground‐truth data will help interpretation of air‐ and space‐borne active and passive microwave radar measurements that were made coincident with this study. In addition, this work may help guide future researchers when choosing FMCW radar measurement parameters, depending on the type of snowpack information their study requires. Copyright © 2004 John Wiley & Sons, Ltd.