bluuebunny/crossref_metadata_2025 huggingface dataset:
Enzyme immobilization on epoxy‐ and 1,1′‐carbonyldiimidazole‐activated methacrylate‐based monoliths
Authors: Benčina Katja , Podgornik Aleš , Štrancar Aleš , Benčina Mojca
Published: July 2004

Monolithic Convective Interaction Media (CIM) have been activated with epoxide and imidazole carbamate functionalities and used as supports for covalent immobilization of protein A, deoxyribonuclease I, and trypsin. The efficiency of immobilization for these proteins was determined from the amount of bound IgG, degradation of DNA, and hydrolysis of Nα‐benzoyl‐L‐arginine ethyl ester, respectively. The respective biological activities of trypsin and the binding capacity of protein A immobilized via imidazole carbamate groups were 11.45 and 2.25 times higher than those obtained for epoxide matrix while they were practically equal for deoxyribonuclease I. The kinetics of immobilization was studied in detail for trypsin under dynamic conditions and revealed that the enzyme immobilized via imidazole carbamate groups already reached its highest activity in 5 min. In contrast, a much longer time was required for immobilization via epoxy groups.
Structural formation of hybrid siloxane‐based polymer monolith in confined spaces
Authors: Kanamori Kazuyoshi , Yonezawa Hideyuki , Nakanishi Kazuki , Hirao Kazuyuki , Jinnai Hiroshi
Published: July 2004

Structural deformation of phase‐separated methylsiloxane gel under the influence of a surface has been studied. Competitive wetting of siloxane gel phase on a surface during phase formation is found to significantly affect the final morphology in a confined space. When the spinodal wavelength is sufficiently shorter than the size of the available space, a uniform bicontinuous structure forms in confined geometry. However, gel skeletons in the vicinity of a surface are elongated with decreasing size of the space, and finally when the size of the space becomes shorter than the spinodal wavelength, all the gel phase wets on a surface, showing a “wetting transition”. Homogeneous bicontinuous methylsiloxane gels were successfully prepared, avoiding such structural deformation, in a long cylindrical fused silica capillary and used for capillary HPLC. The capillary gels exhibited excellent separation efficiency of nitrobenzenes and it was found that the surface character can be altered by incorporating surfactants, which will enable more advanced and extended control of surface character, depending on the analytes.
High‐performance liquid chromatographic enantioseparations on capillary columns containing monolithic silica modified with cellulose tris(3,5‐dimethylphenylcarbamate)
Authors: Chankvetadze Bezhan , Yamamoto Chiyo , Tanaka Nobuo , Nakanishi Kazuki , Okamoto Yoshio
Published: July 2004

Monolithic capillary columns containing native silica gel were modified with cellulose tris(3,5‐dimethylphenylcarbamate) (CDMPC) and used for enantioseparations in capillary liquid chromatography. The method adopted for in situ enantioselective modification of monolithic fused silica capillary columns by coating with CDPMC appears to be fairly simple and fast. High efficiency enantioseparations of test racemic compounds and several chiral drugs were achieved in a short time. It was possible to increase the amount of chiral selector present by multiple coating of monoliths with CDMPC. The baseline enantioseparation of 2,2,2‐trifluoro‐1‐(9‐anthryl)ethanol was achieved in an analysis time less than 30 s with this capillary column. In addition, reproducible enantioseparations were obtained when the chiral selector was removed from the monolithic column by flushing it with appropriate solvent and the column recoated.
Monolithic columns with a gradient of functionalities prepared via photoinitiated grafting for separations using capillary electrochromatography
Authors: Pucci Vincenzo , Raggi Maria Augusta , Svec Frantisek , Fréchet Jean M.J.
Published: July 2004

Stationary phases for capillary electrochromatography with a longitudinal gradient of functionalities have been prepared via photoinitiated grafting of polymer chains onto the pore surface of a porous polymer monolith. In order to achieve the desired retention and electroosmotic flow, the hydrophobic poly(butyl methacrylate‐co‐ethylene dimethacrylate) monolith with optimized porous properties was grafted with a layer of ionizable polymer, poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid). A moving shutter and a neutral density filter were used to control the dose of UV light received at different locations along the monolith in order to create the longitudinal gradient of functionalities. Formation of the desired gradients was confirmed using electron probe microanalysis of different locations along the column. The preparation technique significantly affects performance in the CEC mode as demonstrated on the separations of a model mixture using columns both with homogeneous distribution of grafts and with a gradient of functionality. Columns grafted with the gradient of functionalities were found superior to those functionalized uniformly. A comparison of the performance of the gradient column with another containing evenly distributed functionalities showed the performance benefits of the “gradient” column.
Simple 2D‐HPLC using a monolithic silica column for peptide separation
Authors: Kimura Hiroshi , Tanigawa Tetsuya , Morisaka Hironobu , Ikegami Tohru , Hosoya Ken , Ishizuka Norio , Minakuchi Hiroyoshi , Nakanishi Kazuki , Ueda Mitsuyoshi , Cabrera Karin , Tanaka Nobuo
Published: July 2004

Separation of peptides by fast and simple two‐dimensional (2D)‐HPLC was studied using a monolithic silica column as a second‐dimension (2nd‐D) column. Every fraction from the first column, 5 cm long (2.1 mm ID) packed with polymer‐based cation exchange beads, was subjected to separation in the 2nd‐D using an octadecylsilylated (C18) monolithic silica column (4.6 mm ID, 2.5 cm). A capillary‐type monolithic silica C18 column (0.1 mm ID, 10 cm) was also employed as a 2nd‐D column with split flow/injection. Effluent of the first dimension (1st‐D) was directly loaded into an injector loop of 2nd‐D HPLC. UV and MS detection were successfully carried out at high linear velocity of mobile phase at 2nd‐D using flow splitting for the 4.6 mm ID 2nd‐D column, or with direct connection of the capillary column to the MS interface. Two‐minute fractionation in the 1st‐D, 118‐second loading, and 2‐second injection by the 2nd‐D injector, allowed one minute for gradient separation in the 2nd‐D, resulting in a maximum peak capacity of about 700 within 40 min. The use of a capillary column in the 2nd‐D led to less solvent consumption and better MS detectability compared to a larger‐sized column. This kind of fast and simple 2D‐HPLC utilizing monolithic silica columns will be useful for the separation of complex mixtures in a short time.
Cover Picture: Macromol. Mater. Eng. 7/2004
Authors: Ding Shi‐You , Rumbles Garry , Jones Marcus , Tucker Melvin P. , Nedeljkovic Jovan , Simon Martha N. , Wall Joseph S. , Himmel Michael E.
Published: July 2004

Cover: Graphical representation of a novel bioconjugate consisting of a genetically modified cohesin/dockerin polymer surrounding a single (CdSe)ZnS colloidal quantum dot (QD). Strong binding between protein monomers to form polymers and also with QDs provides a method of producing stable, water‐soluble and luminescent QD species amenable to chromatographic separation.

Further details can be found in the Full Paper by S.‐Y. Ding, G. Rumbles, M. Jones, M. P. Tucker, J. Nedeljkovic, M. N. Simon, J. S. Wall, and M. E. Himmel* on page 622.
Toxicity and efficacy of intensive chemotherapy for children with acute lymphoblastic leukemia (ALL) after first bone marrow or extramedullary relapse
Authors: Thomson Blythe , Park Julie R. , Felgenhauer Judy , Meshinchi Soheil , Holcenberg John , Geyer J. Russell , Avramis Vassilios , Douglas James G. , Loken Michael R. , Hawkins Douglas S.
Published: July 2004

Background

Approximately 25% of children newly diagnosed with acute lymphoblastic leukemia (ALL) will eventually experience leukemic relapse, with bone marrow being the most common site of recurrence. The ability to achieve a durable second remission is complicated by toxicity and resistant disease. We report a novel combination of chemotherapy for relapsed pediatric ALL.

Procedure

Thirty pediatric patients with relapsed medullary (n = 18) and extra‐medullary (n = 12) ALL were enrolled at three pediatric institutions. Following receipt of induction and the first Block A and Block B of intensification, each patient was evaluated for toxicity, efficacy in achieving remission, and long‐term survival. Additionally, minimal residual disease (MRD) detection by multidimensional flow cytometry (MDF) was performed.

Results

During induction, the major non‐hematopoeitic toxicities were mucositis (30% of patients) and bacteremia (50% of patients). Two patients (7%) died of toxicity during induction. Toxicity during intensification Block 1A and 1B was markedly reduced. Eight‐nine percent of patients with marrow disease achieved a remission following induction and intensification. The event‐free survival (EFS) for all patients at 2 and 4 years were 60% (95% CI: 42–78%) and 49% (95% CI: 30–68%), respectively.

Conclusions

This regimen for patients with relapsed ALL was successful in achieving a second remission for the majority of patients with acceptable toxicity. © 2004 Wiley‐Liss, Inc.
Health status of young children during therapy for advanced neuroblastoma
Authors: Nathan P.C. , Furlong W. , De Pauw S. , Horsman J. , Van Schaik C. , Rolland M. , Weitzman S. , Feeny D. , Barr R.D.
Published: July 2004

Background

The purpose of this study was to describe the health status experienced by young children during various phases of therapy for advanced neuroblastoma.

Methods

Nineteen patients aged 2.00–4.99 years at the time of diagnosis of neuroblastoma (stages 3 or 4) who received active therapy between 1996 and 2000 were enrolled on the study. Their parents provided proxy assessments of their health status at a maximum of 10 assessment points during therapy using the Comprehensive Health Status Classification System for Pre‐school Children (CHSCS‐PS), which assesses level of function on 10 separate health domains.

Results

Eighty‐six assessment questionnaires were completed. Maximum morbidity was reported immediately following diagnosis and in the 2–3 weeks following bone marrow transplantation. The greatest morbidity was observed in the pain, self‐care, mobility, and emotion domains.

Conclusions

In addition to facing a high risk of mortality, young children being treated for advanced neuroblastoma also experience considerable morbidity. © 2004 Wiley‐Liss, Inc.
Identification of metastasis‐associated proteins in a human tumor metastasis model using the mass‐mapping technique
Authors: Kreunin Paweena , Urquidi Virginia , Lubman David M , Goodison Steve
Published: July 2004

For most cancer cell types, the acquisition of metastatic ability leads to clinically incurable disease. The identification of molecules whose expression is specifically correlated with the metastatic spread of cancer would facilitate the design of therapeutic interventions to inhibit this lethal process. In order to facilitate metastasis gene discovery we have previously characterized a pair of monoclonal cell lines from the human breast carcinoma cell line MDA‐MB‐435 that have different metastatic phenotypes in immune‐compromised mice. In this study, serum‐free conditioned media was collected from the cultured monoclonal cell lines and a mass mapping technique was applied in order to profile a component of each cell line proteome. We utilized chromatofocusing in the first dimension to obtain a high resolution separation based on protein pI, and nonporous silica reverse‐phase high performance liquid chromatography was used for the second dimension. Selected proteins were identified on the basis of electrospray ionization time of flight mass spectrometry (ESI‐TOF MS) intact protein mapping and matrix‐assisted laser desorption/ionization time of flight mass spectrometry (MALDI‐TOF MS) peptide mass fingerprinting. Using this approach we were able to map over 400 proteins and plot them as a 2‐D map of pI versus accurate Mr. This was performed over a pI range of 4.0–6.2, and a mass range of 6–80 kDa. ESI‐TOF MS data and further analysis using MALDI‐TOF MS confirmed and identified 27 differentially expressed proteins. Proteins associated with the metastatic phenotype included osteopontin and extracellular matrix protein 1, whereas the matrix metalloproteinase‐1 and annexin 1 proteins were associated with the non‐metastatic phenotype. These findings demonstrate that the mass mapping technique is a powerful tool for the detection and identification of proteins in complex biological samples and which are specifically associated with a cellular phenotype.
Wheat leaf proteome analysis using sequence data of proteins separated by two‐dimensional electrophoresis
Authors: Bahrman Nasser , Negroni Luc , Jaminon Odile , Le Gouis Jacques
Published: July 2004

Identifying wheat leaf protein expression is a major challenge of functional genomics. Using two‐dimensional gel electrophoresis 541 wheat leaf proteins were separated and 55 of them were sequenced by nano liquid chromatography‐tandem mass spectrometry. Peptide sequence data were screened against protein banks and expressed sequence tag public banks. Among these 55 spots, 20 proteins were found in wheat and 21 in other grass families (http://www.ncbi.nlm.nih.gov/). Twelve proteins showed similarities with other eukaryotic plant species. One protein showed homology to a bacterial sequence and another protein remained unknown. In 18 cases a significant score was found for the wheat TUC (Tentative Unique Contigs) of the PlantGDB (http://www.plantgdb.org/) data. In several cases, different spots were identified as corresponding to the same protein that can probably be attributed to the hexaploid structure of wheat. The identified proteins were classified in six groups and their role is discussed. Most of them (31/55) are involved in carbohydrate metabolism.
Proteomic analysis of aneuploid lines in the homeologous group 1 of the hexaploid wheat cultivar Courtot
Authors: Dumur Jérôme , Jahier Joseph , Bancel Emmanuelle , Laurière Michel , Bernard Michel , Branlard Gérard
Published: July 2004

Three monosomic lines (MSLs) and three nullisomic lines (NSLs) of the homeologous group 1 and one euploid line of the bread wheat Triticum aestivum cultivar Courtot were used in a proteomic approach to investigate the effects of zero, one or two doses of chromosomes 1A, 1B and 1D on the amount of endosperm proteins. Polypeptides whose amounts changed significantly between each aneuploid line and the euploid line were identified using image analyses of two‐dimensional gel electrophoresis patterns resulting from specific endosperm protein extractions. Matrix‐assisted laser desorption/ionization‐time of flight mass spectrometry and electrospray ionization tandem mass spectrometry were also used for protein identification. Removing one chromosome or a chromosome pair allowed varying responses to be observed for the remaining endosperm protein genes. Compensation phenomena for the high molecular weight glutenin subunits (HMW‐GS) were detected only in the MSLs. Subunits Bx7, By8 and Dy12 were the only HMW‐GS overexpressed (from 152–737%) when chromosomes 1A or 1B or 1D were at hemizygous state. Thirteen new protein spots were detected only in the NSL1D, and seven were identified as HMW‐GS analogs. These seven new spots may result from the expression of inactive genes. The HMW‐GS were of significantly higher volume in MSLs, whereas the low molecular weight glutenin subunits and the γ‐gliadins were of lower volume in aneuploid lines. Most of the down‐regulated proteins in the MSLs were storage proteins encoded at loci located on another chromosome pair. Complex regulations between chromosomes and loci of the homeologous groups 1 and 6 in bread wheat are discussed.
High resolution mass spectrometric alveolar proteomics: Identification of surfactant protein SP‐A and SP‐D modifications in proteinosis and cystic fibrosis patients
Authors: Bai Yu , Galetskiy Dmitry , Damoc Eugen , Paschen Christian , Liu Zhiqiang , Griese Mathias , Liu Shuying , Przybylski Michael
Published: July 2004

In the present study, one‐ and two‐dimensional gel electrophoresis combined with high resolution Fourier transform‐ion cyclotron resonance mass spectrometry (FT‐ICR MS) have been applied as powerful approaches for the proteome analysis of surfactant proteins SP‐A and SP‐D, including identification of structurally modified and truncation forms, in bronchoalveolar lavage fluid from patients with cystic fibrosis, chronic bronchitis and pulmonary alveolar proteinosis. Highly sensitive micropreparation techniques were developed for matrix‐assisted laser desorption/ionization (MALDI) FT‐ICR MS analysis which provided the identification of surfactant proteins at very low levels. Owing to the high resolution, FT‐ICR MS was found to provide substantial advantages for the structural identification of surfactant proteins from complex biological matrices with high mass determination accuracy. Several protein bands corresponding to SP‐A and SP‐D were identified by MALDI‐FT‐ICR MS after electrophoretic separation by one‐ and two‐dimensional gel electrophoresis, and provided the identification of structural modifications (hydroxy‐proline) and degradation products. The high resolution mass spectrometric proteome analysis should facilitate the unequivocal identification of subunits, aggregations, modifications and degradation products of surfactant proteins and hence contribute to the understanding of the mechanistic basis of lung disease pathogenesis.
The influence of interlayer cations on the photo‐oxidative degradation of polyethylene/montmorillonite composites
Authors: Qin Huaili , Zhang Zhenguang , Feng Meng , Gong Fangling , Zhang Shimin , Yang Mingshu
Published: July 2004

The photo‐oxidative degradation of polyethylene/montmorillonite (PE/MMT) nanocomposite and microcomposite has been investigated. It has been found that the rate of photo‐oxidative degradation of PE/MMT nanocomposite and PE/Mn+MMT (where Mn+ stands for multivalent transition metal cation) microcomposites is much faster than that of pure PE. For the PE/MMT nanocomposite, the acceleration of photo‐oxidative degradation is due to the influence of MMT and ammonium ion, in which the influence of ammonium is primary. The decomposition of ammonium ion may create acidic sites on layered silicates; meanwhile, the complex crystallographic structure and habit of clay minerals could also result in some active sites. The reversible photo‐redox reaction of transition metal cations has a catalytic effect in the degradation of the polymer matrix. All these catalytic active sites can accept single electrons from donor molecules of polymer matrix and induce the formation of free radical upon UV irradiation. The generation of free radical leads to the oxidization and break of molecular chain. Thus, the materials suffer degradation and their mechanical strength decreases. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3006–3012, 2004
Arthropod defensins illuminate the divergence of scorpion neurotoxins
Authors: Froy Oren , Gurevitz Michael
Published: July 2004

Defensins are phylogenetically ancient antibacterial polypeptides found in plants and animals. Isolation of the cDNA and genomic sequences encoding the scorpion (Leiurus quinquestriatus hebraeus) defensin revealed similarity to scorpion neurotoxins in gene organization (two exons and a phase I intron) and intron characteristics (conserved acceptor, donor and putative branch sites). This commonality, alongside a similar core structure, protein sequence and bioactivity suggest that arthropod defensins and scorpion neurotoxins share a common ancestor. Interestingly, phylogenetic analysis of defensins and scorpion neurotoxins illuminates for the first time a putative evolutionary trajectory for scorpion sodium and potassium channel neurotoxins. Copyright © 2004 European Peptide Society and John Wiley & Sons, Ltd.
Autonomous ground vehicle path tracking
Authors: Wit Jeff , Crane Carl D. , Armstrong David
Published: July 2004

Autonomous ground vehicle navigation requires the integration of many technologies such as path planning, position and orientation sensing, vehicle control, and obstacle avoidance. The work presented here focuses on the control of a nonholonomic ground vehicle as it tracks a given path. A new path tracking technique called “vector pursuit” is presented. This new technique is based on the theory of screws, which was developed by Sir Robert Ball in 1900. It generates a desired vehicle turning radius based on the vehicle's current position and orientation relative to the position of a point ahead on the planned path and the desired orientation along the path at that point. The vector pursuit algorithm is compared to other geometrical approaches, and it is shown to be more robust, resulting in more accurate path tracking. © 2004 Wiley Periodicals, Inc.
Macroinvertebrate assemblages in streams of interior Alaska following alluvial gold mining
Authors: Milner A. M. , Piorkowski R. J.
Published: July 2004

Alluvial gold mining, or placer mining, represents a major disturbance to stream ecosystems in interior Alaska. This process typically involves re‐routing the stream to one side of the valley while the gravels are removed across the floodplain for processing. The stream is then re‐directed back into a reclaimed new channel after mining has ceased in that section of stream. Macroinvertebrate colonization of reclaimed stream reaches is necessary for benthic community recovery following mining. Macroinvertebrate community assemblages at 36 sites on six streams in interior Alaska were examined. Sites with different mining histories were compared to control sites. TWINSPAN classification and ordination of sites using macroinvertebrate abundance indicated a greater similarity of sites within watersheds than between watersheds even though each watershed had a history of mining including recently mined sites. Significant differences were found for total invertebrate abundance, percentage dominant taxon and mean total biomass of macroinvertebrates between control sites and sites that were recently mined (≤10 years) and sites mined 12–50 years ago. Total macroinvertebrate abundance and biomass was lower and taxon dominance higher in both groups of sites with a history of mining. No significant difference in these or other measures was found for sites where mining occurred upstream. There was also no significant relationship between time since mining and the biotic measures used to summarize macroinvertebrate community structure. Although taxon richness recovered rapidly, no individual taxon was found to be a specific indicator of macroinvertebrate recovery since mining. Copyright © 2004 John Wiley & Sons, Ltd.
Spatial variation in fine sediment transport in small upland streams: the effects of flow regulation and catchment geology
Authors: Bond Nicholas R.
Published: July 2004

In cobble‐ and gravel‐bed streams, fine sediments (<4 mm diameter) are an important component of the bed material that can move at a full range of flows, not just during floods and spates. It has been hypothesized that the constant movement of this fine material, as it passes over the coarse bed, is an important ecological disturbance to plants and animals. In this study, I measured baseflow sediment transport rates across a number of regulated and unregulated sites in an upland catchment comprising isolated regions of granite/sandstone and acid volcanics in southern Victoria, southeastern Australia, as a precursor to a study examining the effects of sediment on aquatic biota. Examined on three separate occasions, transport rates for fine sediments were up to 100 times greater in the granite/sandstone streams, but diversion weirs, which greatly reduced downstream sediment loads in the granite/sandstone areas, moderated these differences. Measured transport rates within unregulated sections of the granite/sandstone streams were roughly equivalent to sediment loads found to disturb benthic communities in other experimental studies. On this basis, abrasion by sediment transport in these streams may be sufficient to influence the structure of benthic communities even at baseflow. This hypothesis forms the basis of other research examining the biota at these sites. Copyright © 2004 John Wiley & Sons, Ltd.
Green hydropower: a new assessment procedure for river management
Authors: Bratrich Christine , Truffer Bernhard , Jorde Klaus , Markard Jochen , Meier Werner , Peter Armin , Schneider Matthias , Wehrli Bernhard
Published: July 2004

Hydropower is the most important renewable electricity source worldwide. It shows clear advantages for the global CO2 balance but creates serious ecological impacts on a local scale. As a consequence, concern for the conservation of natural river ecosystems is growing within society and more people are willing to pay extra for so‐called ‘green electricity’. The definition of ‘green’, however, is not straightforward and customers cannot directly examine the quality of electricity products. Therefore, credible certification of high ecological standards is essential for successful green electricity marketing.

In this paper we introduce a new assessment procedure for evaluating environmentally compatible hydropower production. This so‐called ‘Green Hydro’ concept was developed in the context of a multidisciplinary case study on a 400 MW hydropower scheme in the Southern Alps of Switzerland. The concept guarantees both general standards for different schemes operating in different types of watersheds and flexibility for local particularities. We developed an environmental management matrix that considers basic criteria and eco‐investments and covers five environmental areas of concern (i.e. hydrological character, connectivity, morphology, landscape, and biological communities). The ecological perspective is complemented by five management domains (i.e. instream flow regimes, hydropeaking, reservoir and bedload management, and power plant structures). Applying assessment and modelling tools for the Green Hydro procedure showed that dynamic habitat models allowed quantification of the effects of different instream flow regulations at morphologically distinct sites. In this case, morphological restoration could be more beneficial than increasing the minimum flow.

The first experience with the Green Hydro certification is encouraging. So far, 13 facilities have successfully passed the certification procedure. They produce a total of 186 GWh green electricity per year, which is sufficient for the supply of almost 40 000 households in Switzerland. Copyright © 2004 John Wiley & Sons, Ltd.
The TGFβ inducible early gene plays a central role in the anti‐proliferative response to TGFβ
Authors: Johnsen Steven A. , Subramaniam Malayannan , Effenberger Katharina E. , Spelsberg Thomas C.
Published: July 2004

Signaling through the Transforming Growth Factor‐β (TGFβ)/Smad pathway plays an important role in a variety of cellular processes including the control of cellular proliferation and oncogenesis. The TGFβ Inducible Early Gene (TIEG) is a primary response gene for TGFβ which controls the activity of the Smad pathway. In addition, studies from our laboratory have demonstrated that TIEG expression is lost during the progression of breast cancer. In the present study we utilized a tetracycline inducible TIEG overexpressing breast cancer cell line and TIEG null mouse embryo fibroblasts (MEFs) to establish whether TIEG plays a central role in eliciting the anti‐proliferative effects of TGFβ. We demonstrate that, similar to TGFβ treatment, TIEG overexpression significantly decreases cellular proliferation. Consistent with a role in regulating cellular proliferation, TIEG overexpression increases the expression of the cyclin dependent kinase inhibitor p21. Interestingly, while cellular proliferation of wild‐type MEFs is inhibited by TGFβ, proliferation of TIEG null MEFs is stimulated by TGFβ. Furthermore, TIEG null MEF cells display a decrease in Smad dependent transcription with a concomitant prolonged increase in Smad7 expression compared to wild‐type cells. These data strongly suggest that TIEG plays a central role in the anti‐proliferative response to TGFβ and may explain how a loss of TIEG expression contributes to the development of cancer.
Estimation of the circulation distribution on a rotor blade from detailed near wake velocities
Authors: Mast E. H. M. , Vermeer L. J. , van Bussel G. J. W.
Published: July 2004

The circulation distribution over a blade of a wind turbine model is estimated by use of a vortex model, which is matched with measured wake properties. With near wake velocities and the Biot–Savart law an optimization scheme is constructed to estimate the circulation distribution over the blade using a polynomial function series to approximate the circulation distribution. The velocities resulting from the calculated distribution are compared with the measured data, and deviations are discussed and explained. The vortex model offers insight into how the measured velocities can be separated into induced velocities of the different parts of the vortex system, such as the influence of the tip vortex. The sensitivity of the vortex model to its most uncertain parameters is tested. Finally the circulation distribution obtained with the vortex model is compared with the circulation distribution obtained through application of a blade element momentum (BEM) code. The BEM results show an underestimation of the circulation near the root and an overestimation of the circulation near the tip with respect to the vortex model results. Copyright © 2004 John Wiley & Sons, Ltd.
Composition, components and sources of fine aerosol fractions using multielemental EDXRF analysis
Authors: Marcazzan G. M. , Ceriani M. , Valli G. , Vecchi R.
Published: July 2004

The extensive characterization of the elemental composition of some important components and of major sources of particulate matter PM10 and PM2.5, sampled in parallel three times per week in Milan, for the whole year 2001 is described. More than 250 PM samples were analysed and major, minor and trace element concentrations were obtained by EDXRF. A strong seasonal modulation of particulate matter and element concentrations and an important contribution to PM from secondary compounds originating from gaseous precursors were observed. The main sources and their contribution were obtained by the application of absolute principal factor analysis to the large data set of elemental concentration. Copyright © 2004 John Wiley & Sons, Ltd.
Routine x‐ray fluorescence analysis of powder materials using the ‘VERBA‐XRF’ mode
Authors: Verkhovodov Petro O.
Published: July 2004

A new version of the ‘VERBA‐XRF’ mode was developed for the determination of the contents of principal elements with atomic numbers Z > 10 and SUM9, that is, the sum of the contents of complementary elements with Z < 9 in powder materials without alloying with borax. An original set of equations provides determination of the SUM9. Analysis was made on 120 samples: dust from electric filters, clay, clinker, gypsum, bauxite, slag, candle‐end, shale, schlamm and chalk. The results obtained in the determination of the elements Fe, Ti, Ca, K, S, Si, Al and Mg have relative standard errors of 1–2%. The availability of the value of the SUM9 provided the possibility of determining chemical compositions in samples. The content of mineral white in natural gypsum was calculated. Copyright © 2004 John Wiley & Sons, Ltd.
Index reduction for differential‐algebraic equations by minimal extension
Authors: Kunkel P. , Mehrmann V.
Published: July 2004

In this paper a new index reduction technique is discussed for the treatment of differential‐algebraic systems for which extra structural information is available. Based on this information reduced derivative arrays are formed and instead of using expensive subspace computations the index reduction is obtained by introducing new variables. The new approach is demonstrated for several important classes of differential‐algebraic systems, where the structural information is available. These include multibody systems and circuit simulation problems. The effectiveness of the new approach is demonstrated via numerical examples.
On some mathematical modelling of self‐field MPD thrusters
Authors: Coclici C.A. , Heiermann J. , Moroşanu G. , Wendland W.L.
Published: July 2004

We are concerned with the mathematical modelling of high‐enthalpy compressible plasma flows of magnetoplasmadynamic (MPD) rocket thrusters. A closed system of partial differential equations is associated with corresponding two‐fluid flows which are subjected to strong electromagnetic fields. The numerical solution of the full original model requires nowadays huge computational costs. Therefore we use a heterogeneous domain decomposition where the corresponding coupled model is based on simplified conservation laws in a large subdomain. We establish new transmission conditions for the coupled MPD model, which appear as a byproduct of a detailed asymptotic analysis of the artificial interfaces that arise by domain decomposition. Moreover, a complete coupled mathematical MPD model is formulated, including appropriate outer boundary conditions. The well‐posedness of this model is discussed by using mathematical as well as physical arguments.
A note on the flow equations under space‐time transformation
Authors: Wu Z.‐N.
Published: July 2004

The equations governing incompressible and compressible inviscid flows and written in the physical frame (t,x,y,z) are known to be linearly well‐posed and exhibit elliptic or hyperbolic nature. The linear well‐posedness is considered here for these equations under a space‐time transformation (t,x,y,z) → (τ,ξ,η,ς), where the pseudo‐time τ and the new space coordinate (ξ,η,ς) all depend on (t,x,y,z). This type of transformation is typical in Computational Fluid Dynamics when local time‐stepping is used and it could be useful for uniformly treating problems such as mixed fast‐slow unsteady flows in which the flow is fast unsteady somewhere and slowly unsteady or steady elsewhere and mixed incompressible‐compressible flows. It is found that the transformation may alter the ellipticity, the hyperbolicity, and even the well‐posedness of the original equations.
Recycling of intact dense core vesicles in neurites of NGF‐treated PC12 cells
Authors: Bauer Roslyn A , Khera Rebecca S , Lieber Janet L , Angleson Joseph K
Published: July 2004

Exocytic fusion in neuroendocrine cells does not always result in complete release of the peptide contents from dense core vesicles (DCVs). In this study, we use fluorescence imaging and immunoelectron microscopy to examine the retention, endocytosis and recycling of chromogranin B in DCVs of NGF‐treated PC12 cells. Our results indicate that DCVs retained and retrieved an intact core that was available for subsequent exocytic release. The endocytic process was inhibited by cyclosporine A or by substitution of extracellular Ca2+ with Ba2+ and the total recycling time was less than 5 min.
Gliadin stimulates human monocytes to production of IL‐8 and TNF‐α through a mechanism involving NF‐κB
Authors: Jelı́nková Lenka , Tučková Ludmila , Cinová Jana , Flegelová Zuzana , Tlaskalová-Hogenová Helena
Published: July 2004

Wheat gliadin is the triggering agent in coeliac disease. In this study, we documented that proteolytic fragments of gliadin, in contrast to other food antigens, induced interleukin (IL)‐8 and tumour necrosis factor‐α (TNF‐α) production and significantly increased interferon (IFN)‐γ‐induced cytokine secretion in human monocytic line THP‐1 cells. Stimulation with gliadin resulted in elevated phosphorylation of the IκBα molecule and increased NF‐κB/DNA binding activity that was inhibited by sulfasalazine, l‐1‐tosylamido‐2‐phenylethyl chloromethyl ketone and pyrrolidine dithiocarbamate (PDTC). The activation pathway was shown to be independent of the CD14 molecule. Less mature U‐937 monocytes responded to gliadin stimulation by low IL‐8 secretion, TNF‐α production was not detectable. We propose that gliadin‐induced activation of monocytes/macrophages can participate in mechanisms leading to the impairment of intestinal mucosa in coeliac patients.
On the disulfide‐linker strategy for designing efficacious cationic transfection lipids: an unexpected transfection profile
Authors: Vinod Kumar Valluripalli , Chaudhuri Arabinda
Published: July 2004

Herein, employing a previously reported disulfide‐linker strategy, we have designed and synthesized a novel cationic lipid 2 with a disulfide‐linker and its non‐disulfide control analog lipid 1. The relative efficacies of lipids 1 and 2 in transfecting CHO, COS‐1 and MCF‐7 cells were measured using both reporter gene and whole cell histochemical staining assays. In stark contrast to the expectation based on the disulfide‐linker strategy, the control non‐disulfide cationic lipid 1 showed phenomenally superior in vitro transfection efficacies to its essentially transfection incompetent disulfide counterpart lipid 2. Results in DNase I protection experiments and the electrophoretic gel patterns in the presence of glutathione, taken together, are consistent with the notion that the success of the disulfide‐linker strategy may depend more critically on the DNase I sensitivity of the lipoplexes than on the efficient DNA release induced by intracellular glutathione pool.
hOLF44, a secreted glycoprotein with distinct expression pattern, belongs to an uncharacterized olfactomedin‐like subfamily newly identified by phylogenetic analysis
Authors: Zeng Ling-Chun , Liu Feng , Zhang Xin , Zhu Zhi-Dong , Wang Zhi-Qin , Han Ze-Guang , Ma Wei-Jun
Published: July 2004

Secreted proteins are indispensable for the development and differentiation of multicellular organisms. Cloning and characterization of novel or hypothetical genes encoding these proteins are therefore inviting great incentives. Using bioinformatics tools and experimental approaches, we isolated and characterized a human secreted glycoprotein, hOLF44, which contains a highly conserved olfactomedin‐like (OLF) domain in the C‐terminal. However, phylogenetic analysis revealed that hOLF44 is not clustered into any of the OLF subfamilies containing characterized members, and obviously falls into a newly identified uncharacterized OLF subfamily. Western blot analysis showed that hOLF44 protein is robustly secreted from the transfected COS‐7 cells. Expression levels of hOLF44 mRNA are abundant in placenta, moderate in liver and heart, whereas fairly weak in other tissues examined. Immunohistochemical study on human term placenta demonstrated that hOLF44 is mainly localized extracellularly surrounding the syncytiotrophoblastic cells and very rarely expressed in the maternal decidua layer. These results suggest that hOLF44 may have matrix‐related function involved in human placental and embryonic development, or play a similar role in other physiological processes. The further functional characterization of hOLF44 may provide insights into a better understanding of the newly identified OLF subfamily.
Functional characterization of recombinant batroxobin, a snake venom thrombin‐like enzyme, expressed from Pichia pastoris
Authors: You Weon-Kyoo , Choi Won-Seok , Koh You-Seok , Shin Hang-Cheol , Jang Yangsoo , Chung Kwang-Hoe
Published: July 2004

A thrombin‐like enzyme of Bothrops atrox moojeni venom, batroxobin, specifically cleaves fibrinogen α chain, resulting in the formation of non‐crosslinked fibrin clots. The cDNA encoding batroxobin was cloned, expressed in Pichia pastoris and the molecular function of purified recombinant protein was also characterized. The recombinant batroxobin had an apparent molecular weight of 33 kDa by SDS–PAGE analysis and biochemical activities similar to those of native batroxobin. The purified recombinant protein strongly converted fibrinogen into fibrin clot in vitro, and shortened bleeding time and whole blood coagulation time in vivo. However, it did not make any considerable alterations on other blood coagulation factors. Several lines of experimental evidence in this study suggest that the recombinant batroxobin is a potent pro‐coagulant agent.
Role of CaMKII in hydrogen peroxide activation of ERK1/2, p38 MAPK, HSP27 and actin reorganization in endothelial cells
Authors: Nguyen Andrew , Chen Peng , Cai Hua
Published: July 2004

Growing evidence suggests that reactive oxygen species such as hydrogen peroxide (H2O2) can function as important signaling molecules in vascular cells. H2O2‐activated redox‐sensitive pathways mediate both physiological and pathological responses given the location and concentration of H2O2. We showed previously for the first time that calcium/calmodulin‐dependent protein kinase II (CaMKII) is redox‐sensitive in endothelial cells, mediating H2O2 upregulation of endothelial nitric oxide synthase. This response is always accompanied by an elongation phenotype of endothelial cells, implying modulation of actin cytoskeleton. In the present study, we investigated the role of CaMKII in H2O2 activation of p38 MAPK/heat shock protein 27 (HSP27) pathway and ERK1/2, both of which have been known to regulate actin reorganization in endothelial cells. Addition of H2O2 to bovine aortic endothelial cells increased ERK1/2 phosphorylation and activity, which was attenuated by a specific inhibitor of CaMKII, KN93. KN93 also prevented H2O2 activation of p38 MAPK. Transfection of endothelial cells with a CaMKII‐specific inhibitory peptide (AA 281–309) reduced H2O2 phosphorylation of p38 MAPK and ERK1/2. Furthermore, blockade of CaMKII or janus kinase 2 (JAK2, downstream of CaMKII) prevented H2O2 activation of HSP27. KN93 attenuated, whereas AG490 (JAK2 inhibitor) abolished, H2O2‐induced formation of actin stress fibers. Blockade of ERK1/2 inhibited H2O2 phosphorylation of HSP27 transiently. It also partially prevented H2O2 induction of actin stress fibers. In summary, redox‐sensitive activation of p38 MAPK/HSP27 pathway or ERK1/2 in endothelial cells requires CaMKII. These pathways are at least partially responsible for H2O2 induced reorganization of actin cytoskeleton.
Inhibition of DNA synthesis by K+‐stabilised G‐quadruplex promotes allelic preferential amplification
Authors: Boán Francisco , Blanco Miguel G , Barros Paula , González Ana Isabel , Gómez-Márquez Jaime
Published: July 2004

PCR preferential amplification consists of the inefficient amplification of one allele in a heterozygous sample. Here, we report the isolation of a GC‐rich human minisatellite, MsH43, that undergoes allelic preferential amplification during PCR. This effect requires the existence of a (TGGGGC)4 motif that is able to form a G‐quadruplex in the presence of K+. This structure interferes with the DNA synthesis of the alleles harbouring this motif during PCR The present results are the first demonstration that the formation of G‐quadruplex can be one of the mechanisms involved in some kinds of preferential amplification.
Oxygen‐dependent H2O2 production by Rubisco
Authors: Kim Kangmin , Portis Archie R
Published: July 2004

Oxygen and ribulose‐1,5‐bisphosphate dependent, H2O2 production was observed with several wild type Rubisco enzymes using a sensitive assay. H2O2 and d‐glycero‐2,3‐pentodiulose‐1,5‐bisphosphate, a known and potent inhibitor of Rubisco activity, are predicted products arising from elimination of H2O2 from a peroxyketone intermediate, specific to oxygenase activity. Parallel assays using varying CO2 and O2 concentrations revealed that the partitioning to H2O2 during O2 consumption by spinach Rubisco was constant at 1/260–1/270. High temperature (38 °C), which reduces Rubisco specificity for CO2 versus O2, increased the rates of H2O2 production and O2 consumption, resulting in a small increase in partitioning to H2O2 (1/210). Two Rubiscos with lower specificity than spinach exhibited greater partitioning to H2O2 during catalysis: Chlamydomonas reinhardtii (1/200); and Rhodospirillum rubrum (1/150).
Heterogeneity based on bending of purple membrane containing bacteriorhodopsin
Authors: Mostafa Hamdy I.A
Published: July 2004

The first and second derivatives of dielectric spectra have evidenced the existence of two interacting states of purple membrane (PM) that respond differently to the intensity of illuminating light providing, this way, underlying consequences to the heterogeneous behavior of bacteriorhodopsin (bR). It is of particular interest to note that the rotational diffusion coefficient of PM has exhibited non‐linearity versus light intensity. The explored non‐linearity in electrical properties beers, thereby, on changes in PM size. The non‐linear variations in PM bending might initiate, in consequence, variations in the dipole moment (permanent and induced) and dc‐conductivity of PM patches. Proposal based on PM bending has been introduced to correlate the light intensity effect to the PM lipid environment. Modulation of the global structure of PM and, in turn, its electrical properties by an external perturbation (e.g., light) could be of interest in biotechnological applications based on optoelectronic properties of bR.
Staurosporine restores GTPγS induced block of rapid endocytosis in chromaffin cells
Authors: Henkel Andreas Wolfram , Vogt Tobias Kristian , Henkel Maria Kerstin
Published: July 2004

Fast capacitance measurements demonstrated that chromaffin cells retrieve membrane by several kinetically different pathways. Here, we show that rapid endocytosis is blocked and slow endocytosis reduced by intracellular application of GTPγS, an activator of G‐proteins, but not by the competitive blocker GDPβS. The inhibition of rapid endocytosis by GTPγS can be restored with GDPβS or staurosporine completely. But only staurosporine partially abolishes the reduction of slow endocytosis by GTPγS. Besides triggering exocytosis, GTPγS elicits large exo‐ and endocytotic vesicles that contributed significantly to the total membrane traffic, indicating a third pathway of membrane shuttle.
Risk of breast cancer with estrogen‐progestin replacement therapy
Authors:   Committee on Gynecologic Practice
Published: July 2004

Recent articles have examined the association between the use of combination estrogen‐progestin regimens for hormone replacement therapy (HRT) and the risk of breast cancer. The objective of this Committee Opinion is to evaluate critically the presented evidence. Although epidemiologic studies suggest that the addition of progestins to estrogens may increase the risk of breast cancer, this increased risk has not been proved. The American College of Obstetricians and Gynecologists continues to recommend that HRT be considered as a treatment to relieve vasomotor symptoms and genitourinary tract atrophy and to reduce the risk of osteoporosis and, potentially, cardiovascular disease. Postmenopausal women should be apprised of the current understanding of the risks and benefits of HRT. When considering the use of HRT for longer than 5 years, the clinician and individual patient should weigh the benefits versus the potential side effects and risks for that particular patient.
Von Willebrand's disease in gynecologic practice
Authors: Committee on Gynecologic Practice
Published: July 2004

Von Willebrand's disease is one of the most common inherited bleeding disorders. Inherited and acquired disorders of coagulation and hemostasis should be considered in the differential diagnosis of menorrhagia and abnormal uterine bleeding. This Committee Opinion provides screening recommendations for von Willebrand's disease and describes treatment options.
Drug-associated nutritional problems in older persons
Authors: Chau Long , Ratnaike Ranjit N
Published: July 2004

Nutrient inadequacies, especially in older persons, impact adversely on health, increasing the risk of acute and chronic disease and prolonging recovery from illness. Malnutrition is a condition due to an inadequate calorie and micronutrient intake that fails to meet the basic requirements for body maintenance, growth and development. Malnutrition often occurs in older people in acute hospital settings, among residents in nursing homes and in long-term care. Malnutrition in institutionalized older people is as high as 40–50%.