bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation, characterization, and adsorption properties for metal ions of a novel chelating resin containing sulfoxide and diethylene glycol
Authors: Ji Chunnuan , Qu Rongjun , Bo Cao Cheng , Chen Huo , Xu Qiang , Sun Changmei , Wang Chunhua , Yuan Huafang , Zhou Jun
Published: September 2006

A novel chelating resin containing sulfoxide and diethylene glycol, poly{4‐vinylbenzyl‐[2‐2‐(hydroxyethyl)ethoxyl]sulfoxide} (PVESO) was synthesized using chloromethylated polystyrene (PS‐Cl) as material. Its structure was characterized by elemental analysis, infrared spectra, and scanning electron microscopy (SEM). The adsorption capacities of the resin for Hg2+, Ag+, Cu2+, Zn2+, and Pb2+ at various pH values were determined. The maximum adsorption capacities for Hg2+ and Ag+ were 1.56 and 0.75 mmol g−1 respectively. The resin had high selectivity for Hg2+ and Ag+ over the pH range 1.0–7.0. The adsorption capacities for Hg2+ and Ag+ under competitive condition were also determined by batch experiment method. In addition, the adsorption kinetics of the resin towards Hg2+ at different temperatures was also investigated. The results showed that the adsorption rate was governed by film diffusion at 20°C and 25°C, by particle diffusion at 30°C and 35°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6054–6059, 2006
Biological Evaluation of Chalcones and Analogues as Hypolipidemic Agents
Authors: Santos Lorena , Curi Pedrosa Rozangela , Correa Rogério , Cechinel Filho Valdir , Nunes Ricardo José , Yunes Rosendo Augusto
Published: September 2006

In order to evaluate the anti‐hyperlipidemic effect of synthetic chalcones and some analogues, nineteen compounds with different substituents in both rings were synthesized and hypolipidemic activities were measured in vivo using Triton WR1339 acute and hypercaloric chronic assays. 4′,4‐dichlorochalcone, 3′,4′,4‐trichlorochalcone, and 4′‐chlorochalcone gave an excellent decrease in serum total cholesterol and triglycerides in the acute assay. These compounds also showed significant anti‐lipidemic activity in the chronic assay.
Synthesis and Evaluation of Antimicrobial Activity of Novel Hydrazino and N‐Benzylidinehydrazino‐Substituted 4,8‐Dihydro‐1H,3H‐pyrimido[4,5‐d]pyrimidin‐2,7‐dithiones
Authors: Sharma Pratibha , Rane Nilesh , Pandey Priti
Published: September 2006

A number of novel pyrimido[4,5‐d]pyrimidine‐2,7‐dithone derivatives bearing hydrazino and N‐benzylidinehydrazino substitution were efficiently synthesized and screened for in vitro antibacterial activities against the representative panel of three Gram‐positive and two Gram‐negative bacteria. All the synthesized compounds showed the potent inhibitory action against Gram‐positive bacteria. Particularly, N‐benzylidinehydrazino‐substituted compounds imparted profound effect. Furthermore, the Connolly‐accessible surface area values were also calculated for the target compounds and correlated with the expressed biological activity.
Abrogation of skin disease in LUPUS‐prone MRL/FASlpr mice by means of a novel tylophorine analog
Authors: Choi Jin‐Young , Gao Wenli , Odegard Jared , Shiah Her‐Shyong , Kashgarian Michael , McNiff Jennifer M. , Baker David C. , Cheng Yung‐Chi , Craft Joseph
Published: September 2006

Objective

To test the therapeutic effect of DCB‐3503, a synthetic compound derived from a natural product that inhibits NF‐κB, on end‐organ disease in the MRL‐Faslpr murine model of systemic lupus erythematosus (SLE).

Methods

Eight‐week‐old female MRL/Faslpr mice were treated intraperitoneally with a low (2 mg/kg) or high (6 mg/kg) dose of DCB‐3503 for 10 weeks. Control groups were administered vehicle treatment alone (negative control) or 25 mg/kg cyclophosphamide (positive control). Mice were bled before (8 weeks) and during (13 weeks) treatment, and when they were killed (20 weeks), and serum samples were analyzed for total IgM and IgG levels and autoantibody titers. When the mice were killed, spleen and lymph nodes (axillary, brachial, and cervical) were examined by flow cytometric analysis. The presence of skin and renal disease was determined by histopathologic analysis.

Results

DCB‐3503 reduced anti–double‐stranded DNA and antichromatin autoantibodies and nearly abrogated inflammatory skin disease in MRL/Faslpr mice; however, it had little effect on histologic kidney disease. Treated mice did not have hematologic or hepatic toxicity. These data indicate that end‐organ disease in MRL/Faslpr mice responds differentially to NF‐κB inhibitor.

Conclusion

DCB‐3503 causes significant abrogation of skin disease in MRL/Faslpr mice and may potentially be beneficial in the treatment of inflammatory skin disease in SLE.
The influence of aerobic fitness and fibromyalgia on cardiorespiratory and perceptual responses to exercise in patients with chronic fatigue syndrome
Authors: Cook Dane B. , Nagelkirk Paul R. , Poluri Ashok , Mores John , Natelson Benjamin H.
Published: September 2006

Objective

To investigate cardiorespiratory and perceptual responses to exercise in patients with chronic fatigue syndrome (CFS), accounting for comorbid fibromyalgia (FM) and controlling for aerobic fitness.

Methods

Twenty‐nine patients with CFS only, 23 patients with CFS plus FM, and 32 controls completed an incremental bicycle test to exhaustion. Cardiorespiratory and perceptual responses were measured. Results were determined for the entire sample and for 18 subjects from each group matched for peak oxygen consumption.

Results

In the overall sample, there were no significant differences in cardiorespiratory parameters between the CFS only group and the controls. However, the CFS plus FM group exhibited lower ventilation, lower end‐tidal CO2, and higher ventilatory equivalent of carbon dioxide compared with controls, and slower increases in heart rate compared with both patients with CFS only and controls. Peak oxygen consumption, ventilation, and workload were lower in the CFS plus FM group. Subjects in both the CFS only group and the CFS plus FM group rated exercise as more effortful than did controls. Patients with CFS plus FM rated exercise as significantly more painful than did patients with CFS only or controls. In the subgroups matched for aerobic fitness, there were no significant differences among the groups for any measured cardiorespiratory response, but perceptual differences in the CFS plus FM group remained.

Conclusion

With matching for aerobic fitness, cardiorespiratory responses to exercise in patients with CFS only and CFS plus FM are not different from those in sedentary healthy subjects. While CFS patients with comorbid FM perceive exercise as more effortful and painful than do controls, those with CFS alone do not. These results suggest that aerobic fitness and a concurrent diagnosis of FM are likely explanations for currently conflicting data and challenge ideas implicating metabolic disease in the pathogenesis of CFS.
Premature induction of hypertrophy during in vitro chondrogenesis of human mesenchymal stem cells correlates with calcification and vascular invasion after ectopic transplantation in SCID mice
Authors: Pelttari Karoliina , Winter Anja , Steck Eric , Goetzke Katrin , Hennig Thea , Ochs Bjoern Gunnar , Aigner Thomas , Richter Wiltrud
Published: September 2006

Objective

Functional suitability and phenotypic stability of ectopic transplants are crucial factors in the clinical application of mesenchymal stem cells (MSCs) for articular cartilage repair, and might require a stringent control of chondrogenic differentiation. This study evaluated whether human bone marrow–derived MSCs adopt natural differentiation stages during induction of chondrogenesis in vitro, and whether they can form ectopic stable cartilage that is resistant to vascular invasion and calcification in vivo.

Methods

During in vitro chondrogenesis of MSCs, the expression of 44 cartilage‐, stem cell–, and bone‐related genes and the deposition of aggrecan and types II and X collagen were determined. Similarly treated, expanded articular chondrocytes served as controls. MSC pellets were allowed to differentiate in chondrogenic medium for 3–7 weeks, after which the chondrocytes were implanted subcutaneously into SCID mice; after 4 weeks in vivo, samples were evaluated by histology.

Results

The 3‐stage chondrogenic differentiation cascade initiated in MSCs was primarily characterized by sequential up‐regulation of common cartilage genes. Premature induction of hypertrophy‐related molecules (type X collagen and matrix metalloproteinase 13) occurred before production of type II collagen and was followed by up‐regulation of alkaline phosphatase activity. In contrast, hypertrophy‐associated genes were not induced in chondrocyte controls. Whereas control chondrocyte pellets resisted calcification and vascular invasion in vivo, most MSC pellets mineralized, in spite of persisting proteoglycan and type II collagen content.

Conclusion

An unnatural pathway of differentiation to chondrocyte‐like cells was induced in MSCs by common in vitro protocols. MSC pellets transplanted to ectopic sites in SCID mice underwent alterations related to endochondral ossification rather than adopting a stable chondrogenic phenotype. Further studies are needed to evaluate whether a more stringent control of MSC differentiation to chondrocytes can be achieved during cartilage repair in a natural joint environment.
Antiplatelet and anticoagulant therapy in patients with giant cell arteritis
Authors: Lee Michael S. , Smith Scott D. , Galor Anat , Hoffman Gary S.
Published: September 2006

Objective

Vision loss and cerebrovascular accidents often complicate giant cell arteritis (GCA). Antiplatelet and anticoagulant therapy reduce the risk of stroke in other populations. We sought to determine whether antiplatelet or anticoagulant therapy reduces ischemic complications in patients with GCA.

Methods

A retrospective chart review for patients with GCA was conducted. Included patients fulfilled modified 1990 American College of Rheumatology criteria for GCA. Collected information included demographic data, dates of antiplatelet or anticoagulant use, vision loss or stroke, and presence of bleeding complications and cerebrovascular risk factors.

Results

A total of 143 patients were included with a mean followup period of 4 years. The cohort included 109 women (76%) and 34 men (24%) with a mean age of 71.8 years. A total of 104 patients (73%) had a biopsy‐proven diagnosis. Eighty‐six patients (60.1%) had received long‐term antiplatelet or anticoagulant therapy, including 18 (12.6%) who did not start therapy until after an ischemic event had occurred. Antiplatelet agents or anticoagulants were not used in 57 patients (39.9%). Overall, 11 of 68 patients (16.2%) had an ischemic event while receiving antiplatelet or anticoagulant therapy, compared with 36 of 75 patients (48.0%) not receiving such therapy (P < 0.0005). Univariate analysis failed to show a statistical difference between groups in regard to cerebrovascular risk factors, age, sex, or biopsy‐proven diagnosis. Bleeding complications occurred in 2 patients receiving aspirin, 1 patient receiving warfarin, and 5 patients who did not receive anticoagulant or antiplatelet therapy.

Conclusion

Antiplatelet or anticoagulant therapy may reduce the risk of ischemic events in patients with GCA. An increased risk of bleeding complications was not observed.
Disconnect between inflammation and joint destruction after treatment with etanercept plus methotrexate: Results from the trial of etanercept and methotrexate with radiographic and patient outcomes
Authors: Landewé Robert , van der Heijde Désirée , Klareskog Lars , van Vollenhoven Ronald , Fatenejad Saeed
Published: September 2006

Objective

To determine the relationship between disease activity and radiographic progression of joint destruction in patients with rheumatoid arthritis (RA) treated with methotrexate (MTX), those treated with etanercept, and those treated with the combination of MTX plus etanercept.

Methods

Baseline, 12‐month, and 24‐month data from the Trial of Etanercept and Methotrexate with Radiographic and Patient Outcomes database were analyzed. The dependent variable was the 1‐year change in the modified Sharp/van der Heijde score (Sharp score); therefore, 2 interval changes per patient were available. Interval change in the Sharp score was modeled by time (years), treatment, disease activity, and the interaction (disease activity × treatment). Disease activity was reflected by the time‐averaged Disease Activity Score (taDAS) and the time‐averaged C‐reactive protein (taCRP) level, which were calculated per 1‐year interval. Generalized mixed linear modeling (GMLM) was used to adjust for within‐patient correlation.

Results

GMLM confirmed a significant interaction between treatment and the taCRP level and taDAS with respect to the change in Sharp score (P = 0.012 and P = 0.03, respectively). In patients treated with MTX alone, radiographic progression increased with an increasing taCRP level or taDAS, although progression rates were low in patients whose disease was in remission and in those with low‐to‐moderate disease activity. This relationship was less clear in patients treated with etanercept and was absent in those who received combination therapy.

Conclusion

Combination therapy with MTX plus etanercept uncouples the classic relationship between disease activity and radiographic progression in patients with RA.
Interleukin‐1α induction of tensile weakening associated with collagen degradation in bovine articular cartilage
Authors: Temple Michele M. , Xue Yang , Chen Michael Q. , Sah Robert L.
Published: September 2006

Objective

To determine whether interleukin‐1α (IL‐1α) induces tensile weakening of articular cartilage that is concomitant with the loss of glycosaminoglycans (GAGs) or the subsequent degradation of the collagen network.

Methods

Explants of young adult bovine cartilage obtained from the superficial (including the articular surface), middle, and deep layers were cultured with or without IL‐1α for 1 week or 3 weeks. Then, portions of the explants were analyzed for their tensile properties (ramp modulus, strength, and failure strain); other portions of explants and spent culture medium were analyzed for the amount of GAG and the amount of cleaved, denatured, and total collagen.

Results

The effect of IL‐1α treatment on cartilage tensile properties and content was dependent on the duration of culture and the depth of the explant from the articular surface. The tensile strength and failure strain of IL‐1α–treated samples from the superficial and middle layers were lower after 3 weeks of culture, but not after 1 week of culture. However, by 1 week of culture, IL‐1α had already induced release of the majority of tissue GAGs into the medium, without detectable loss or degradation of collagen. In contrast, after 3 weeks of culture, IL‐1α induced significant collagen degradation, as indicated by the amount of total, cleaved, or denatured collagen in the medium or in explants from the superficial and middle layers.

Conclusion

IL‐1α–induced degradation of cartilage results in tensile weakening that occurs subsequent to the depletion of GAG and concomitant with the degradation of the collagen network.
Composition of calcifications in children with juvenile dermatomyositis: Association with chronic cutaneous inflammation
Authors: Pachman Lauren M. , Veis Arthur , Stock Stuart , Abbott Kathy , Vicari Frank , Patel Pravin , Giczewski Diana , Webb Catherine , Spevak Lyudmila , Boskey Adele L.
Published: September 2006

Objective

Calcific deposits develop in 20–40% of children with juvenile dermatomyositis (juvenile DM), contributing to disease morbidity and mortality. This study was undertaken to define the structure and composition of these deposits and to characterize their association with chronic inflammation.

Methods

We examined calcific deposits from 5 children with juvenile DM (2 boys and 3 girls). The crystal structure and mineral content of the deposits was analyzed by x‐ray diffraction, Fourier transform infrared spectroscopy, and imaging. The protein content of the deposits, following solubilization, was assayed by Western blotting.

Results

All 5 children had both a young age at disease onset (mean ± SD 3.3 ± 1.9 years) and, despite therapy, persistent cutaneous inflammation (mean ± SD duration 81.3 ± 58.7 months). The bone proteins, osteopontin, osteonectin, and bone sialoprotein, were identified in the protein extracts; the only mineral detected was hydroxyapatite, but the tissue was distinct from bone, with an extremely high mineral content and an irregular distribution of mineral.

Conclusion

These results indicate that chronic cutaneous inflammation may contribute to the formation of hydroxyapatite‐containing pathologic calcifications in children with juvenile DM.
Assembly of DNA Nanostructures with Branched Tris‐DNA
Authors: Kuroda Takahiro , Sakurai Yoshimasa , Suzuki Yukinao , Nakamura Akiko O. , Kuwahara Masayasu , Ozaki Hiroaki , Sawai Hiroaki
Published: September 2006

Branched tris‐DNA, in which two oligonucleotides of the same sequence and one other oligonucleotide of a different sequence are connected with a rigid central linker, was prepared chemically by using a DNA synthesizer. Two branched tris‐DNA molecules with complementary DNA sequences form dimer and tetramer as well as linear and spherical oligomer complexes. The complex formation was studied by UV/thermal denaturation, enzyme digestion, gel electrophoresis, and AFM imaging.
Chemolithotrophic perchlorate reduction linked to the oxidation of elemental sulfur
Authors: Ju Xiumin , Field Jim A. , Sierra‐Alvarez Reyes , Salazar Margarita , Bentley Harold , Bentley Richard
Published: September 2006

Perchlorate (ClO) contamination of ground and surface water has been recently recognized as a widespread environmental problem. Biological methods offer promising perspectives of perchlorate remediation. Facultative anaerobic bacteria couple the oxidation of organic and inorganic electron‐donating substrates to the reduction of perchlorate as a terminal electron acceptor, converting it completely to the benign end‐product, chloride. Insoluble inorganic substrates are of interest for low maintenance bioreactor or permeable reactive barrier systems because they can provide a long‐term supply of electron donor without generating organic residuals. The main objective of this research was to investigate the feasibility of utilizing elemental sulfur (S0) as an insoluble electron donor for the biological reduction of perchlorate. A chemolithotrophic enrichment culture derived from aerobic activated sludge was obtained which effectively coupled the oxidation of elemental sulfur to sulfate with the reduction of perchlorate to chloride and gained energy from the process for cell growth. The enrichment culture grew at a rate of 0.41 or 0.81 1/d in the absence and presence of added organic carbon for cell growth, respectively. The enrichment culture was also shown to carry out sulfur disproportionation to a limited extent as evidenced by the formation of sulfide and sulfate in the absence of added electron acceptor. When nitrate and perchlorate were added together, the two electron acceptors were removed simultaneously after an initial partial decrease in the nitrate concentration. Biotechnol. Bioeng. 2007;96:1073–1082. © 2006 Wiley Periodicals, Inc.
Synthesis and Evaluation of an α‐C‐Galactosylceramide Analogue that Induces Th1‐biased Responses in Human Natural Killer T Cells
Authors: Lu Xuequan , Song Liping , Metelitsa Leonid S. , Bittman Robert
Published: September 2006

An α‐galactosylceramide (αGalCer, 1) and its isosteric C‐glycoside analogue (2) were found to possess promising immunostimulatory activity because of their ability to activate natural killer T (NKT) cells. We report the synthesis of compound 3, a truncated nonisosteric C‐αGalCer analogue, that like 2 is not enzymatically labile at the glycosidic linkage, but has the anomeric carbon directly bonded to the C1 of the phytoceramide backbone. We compared the biological activity of the three ligands using an in vitro system with human dendritic cells as the antigen‐presenting cells and human NKT cells as the responding cells. Although 3 was a less potent agonist for NKT cells than 1 and 2, it induced cytokine production with the highest IFN‐γ:IL‐4 and IFN‐γ:IL‐13 ratios. Therefore, our data suggest that the new mimetic of αGalCer might preferentially promote Th1‐immune responses and serve as a potent adjuvant in the immunotherapy of cancer and infectious diseases.
Migration of bone marrow stromal cells in 3D: 4 Color methodology reveals spatially and temporally coordinated events
Authors: Thibault Marc M. , Buschmann Michael D.
Published: September 2006

The cytoskeleton plays a central role in many cell processes including directed cell migration. Since most previous work has investigated cell migration in two dimensions (2D), new methods are required to study movement in three dimensions (3D) while preserving 3D structure of the cytoskeleton. Most previous studies have labeled two cytoskeletal networks simultaneously, impeding an appreciation of their complex and dynamic interconnections. Here we report the development of a 4 color method to simultaneously image vimentin, actin, tubulin and the nucleus for high‐resolution confocal microscopy of bone‐marrow stromal cells (BMSCs) migrating through a porous membrane. Several methods were tested for structural preservation and labeling intensity resulting in identification of an optimized simultaneous fixation and permeabilization method using glutaraldehyde, paraformaldehyde and Triton X‐100 followed by a quadruple fluorescent labeling method. This procedure was then applied at a sequence of time points to migrating cells, allowing temporal progression of migration to be assessed by visualizing all three networks plus the nucleus, providing new insights into 3D directed cell migration including processes such as leading edge structure, cytoskeletal distribution and nucleokinesis. Colocalization of actin and microtubules with distinct spatial arrangements at the cellular leading edge during migration, together with microtubule axial polarization supports recent reports indicating the pivotal role of microtubules in directed cell migration. This study also provides a foundation for 3D migration studies versus 2D studies, providing precise and robust methods to attain new insights into the cellular mechanisms of motility. Cell Motil. Cytoskeleton 2006. © 2006 Wiley‐Liss, Inc.
Living markers for actin block myosin‐dependent motility of plant organelles and auxin
Authors: Holweg Carola L.
Published: September 2006

Expression‐based techniques using recombinant actin‐binding proteins (ABPs) have been developed as advantageous means of visualising actin filaments. As actin function is linked to the movement of cellular cargoes, and overexpression of ABPs may compete with endogenous cytoskeletal proteins, such as myosins, secondary effects on cellular motility might be observed during actin visualisation. Cytoplasmic streaming and auxin transport were chosen as examples of cargo movement and investigated in two Arabidopsis thaliana lines stably transformed with fluorescently labelled talin (GFP‐mTn) or fimbrin (GFP‐FABD2). In both lines, the maximal streaming velocity of organelles was reduced to 80% in hypocotyl epidermal cells, where actin was broadly equally labelled by both ABPs. In contrast, observations of streaming and actin organisation during treatments with cytochalasin D (CD) suggested GFP‐mTn‐labelled actin to remain more stable. Furthermore, basipetal auxin transport was undisturbed in the GFP‐FABD2 line but reduced by GFP‐mTn. Remarkably, treatments with CD and 2,3‐butanedione monoxime, which immobilizes myosin by impairing its ATPase, produced not only failures in organelle movement but also in basipetal auxin transport in the wild‐type. These observations suggest that myosin is involved in processes of auxin translocation. In parallel, reduced motility in transgenic plants may be explained by a disturbed acto‐myosin interplay, if overexpressed ABPs block the processive movement of myosin along actin filaments. This report shows that the use of live markers for actin visualisation may affect motility of cellular compounds and underlines the general need for critical investigation of actin‐related processes in wild‐type as well as transgenic plants prior to further interpretation. Cell Motil. Cytoskeleton 2006. © 2006 Wiley‐Liss, Inc.
Shroom4 (Kiaa1202) is an actin‐associated protein implicated in cytoskeletal organization
Authors: Yoder Michael , Hildebrand Jeffrey D.
Published: September 2006

All animal cells utilize a specialized set of cytoskeletal proteins to determine their overall shape and the organization of their intracellular compartments and organelles. During embryonic development, the dynamic nature of the actin cytoskeleton is critical for virtually all morphogenic events requiring changes in cell shape, migration, adhesion, and division. The behavior of the actin cytoskeleton is modulated by a myriad of accessory proteins. Shroom3 is an actin binding protein that regulates neural tube morphogenesis by eliciting changes in cell shape through a myosin II‐dependent pathway. The Shroom‐related gene SHROOM4 (formerly called KIAA1202) has also been implicated in neural development, as mutations in this gene are associated with human X‐linked mental retardation. To better understand the function of Shrm4 in embryonic development, we have cloned mouse Shroom4 and characterized its protein product in vivo and in vitro. Shroom4 is expressed in a wide range of cell types during mouse development, including vascular endothelium and the polarized epithelium of the neural tube and kidney. In endothelial cells and embryo fibroblasts, endogenous Shroom4 co‐distributes with myosin II to a distinct cytoplasmic population of F‐actin and ectopic expression of Shroom4 in multiple cell types enhances or induces the formation of this actin‐based structure. This localization is mediated, at least in part, by the direct interaction of Shroom4 and F‐actin. Our results suggest that Shroom4 is a regulator of cytoskeletal architecture that may play an important role in vertebrate development. Cell Motil. Cytoskeleton 2006. © 2006 Wiley‐Liss, Inc.
Usage SLA‐based scheduling in Grids
Authors: Dumitrescu Catalin L. , Raicu Ioan , Foster Ian
Published: September 2006

Managing usage service level agreements (uSLAs) within environments that integrate participants and resources spanning multiple physical institutions is a challenging problem. Running workloads in such environments is often a similarly challenging problem owing to the scale of the environment, and to the resource partitioning based on various sharing strategies. Also, a resource may be taken down during a job execution, be improperly set up or fail job execution. Such elements have to be taken into account whenever targeting a Grid environment for problem solving. In this paper we explore uSLA‐based scheduling on a real Grid, Grid3, by means of a specific workload (the BLAST workload) and a specific scheduling framework, GRUBER (an architecture and toolkit for resource uSLA specification and enforcement). The paper provides extensive experimental results and comparisons with other scheduling strategies. We also address, in great detail, the performance of different uSLA‐based site selection strategies and the overall performance in scheduling workloads over Grid3 with workload sizes ranging from 10 to 10 000 jobs. Copyright © 2006 John Wiley & Sons, Ltd.
Performance of computationally intensive parameter sweep applications on Internet‐based Grids of computers: the mapping of molecular potential energy hypersurfaces
Authors: Reyes S. , Muñoz‐Caro C. , Niño A. , Badia R. M. , Cela J. M.
Published: September 2006

This work focuses on the use of computational Grids for processing the large set of jobs arising in parameter sweep applications. In particular, we tackle the mapping of molecular potential energy hypersurfaces. For computationally intensive parameter sweep problems, performance models are developed to compare the parallel computation in a multiprocessor system with the computation on an Internet‐based Grid of computers. We find that the relative performance of the Grid approach increases with the number of processors, being independent of the number of jobs. The experimental data, obtained using electronic structure calculations, fit the proposed performance expressions accurately. To automate the mapping of potential energy hypersurfaces, an application based on GRID superscalar is developed. It is tested on the prototypical case of the internal dynamics of acetone. Copyright © 2006 John Wiley & Sons, Ltd.
Adsorption Isotherm of CO on Pt(111) Electrodes
Authors: Cuesta Angel , del Carmen Pérez María , Rincón Alejandro , Gutiérrez Claudio
Published: September 2006

We have determined, for the first time, the equilibrium CO coverage of Pt(111) electrodes at room temperature in 0.1 M H2SO4 as a function of the CO partial pressure using CO‐stripping cyclic voltammetry. Fourier‐transform infrared (FT‐IR) spectroscopy was used to confirm qualitatively the coverage values obtained.
pH‐Driven Cu2+ Translocation in Ferrocene‐Containing Ligands
Authors: Pallavicini Piersandro , Dacarro Giacomo , Mangano Carlo , Patroni Stefano , Taglietti Angelo , Zanoni Robertino
Published: September 2006

The ligands L1H4, L2H2, and L3H4 have been synthesized, featuring two, one, and two ferrocene‐functionalized diamino‐diamido compartments, respectively. The coordination chemistry of the ligands towards Cu2+ has been fully characterized by means of potentiometric and spectrophotometric titrations, which allowed us to determine the protonation constants of the ligands, the formation constants of their complexes, and their coordination geometry. L1H4 and L2H2 feature additional diaminopyridine and bis(aminoquinoline) binding sites, respectively, and are capable of the pH‐driven translocation of two and one Cu2+ cations, respectively. Electrochemical experiments (CV) coupled with pH‐metric titrations demonstrate that while the coordination of Cu2+ to the compartments more distant from ferrocene (Fc), i.e. diaminopyridine in L1H4 and bis(aminoquinoline) in L2H2 leaves the oxidation potential of Fc unchanged, the translocation of the Cu2+ cation(s) inside the diamino‐diamido compartment(s) is signaled by a peculiar lowering of the Fc oxidation potential. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Enantioselectivity of basic analytes in CZE enantioseparation under reversed‐polarity mode using sulfated β‐cyclodextrins as chiral selectors: An unusual temperature effect
Authors: Lin Chen‐Hsing , Kuo Chia‐Ming , Liu Yu‐Chih , Cheng Hsu‐Tun , Lin Wann‐Yin , Wu Jong‐Chang , Wang Li‐Fen , Lin Ching‐Erh
Published: September 2006

Temperature effects on the enantioselectivity of basic analytes in CZE enantioseparation were studied under reversed‐polarity mode using randomly sulfate‐substituted β‐CDs (MI‐S‐β‐CD) as chiral seletors. Two catecholamines (epinephrine and isoproterenol) and two structurally related compounds (octopamine and norephedrine) were selected as test compounds in an electrophoretic system at low pH. The mobility differences between the (+)‐enantiomers and the (−)‐enantiomers of the two catecholamines and dopamine at 40°C are greater than those at 25°C with MI‐S‐β‐CD, even at a concentration as low as 0.3% w/v. Thus the enantioselectivity of these three basic analytes increases with increasing temperature. This phenomenon results from the inequality of the temperature effect on the mobility of the two enantiomers. In contrast, norephedrine behaves differently. The (+)‐enantiomers of these basic analytes were found to migrate faster than the (−)‐enantiomers. Consequently, the unusual temperature effect on the enantioselectivity can be observed when the mobility difference of the (+)‐enantiomer between 40 and 25°C is greater than that of the (−)‐enantiomer using MI‐S‐β‐CD at a concentration greater than about 0.7% w/v for enantioseparation of isoproterenol, 0.4% w/v for epinephrine, and 0.3% w/v for octopamine. This unusual temperature effect offers the advantages to enhance enantioselectivity, to improve enantioseparation, and to reduce migration times.
Production of Lactic Acid from Barley: Strain Selection, Phenotypic and Medium Optimization
Authors: Venus J. , Richter K.
Published: September 2006

Originally, lactic acid was produced from pure starch or from glucose. Increasingly, however, agricultural feedstocks such as grains and green biomass are also being used as raw materials for the production of microbial lactic acid. A high productivity lactic acid bacterium strain was selected, process parameters were optimized for the batch fermentation on a laboratory scale, and its lactate productivity for cultivation on a barley hydrolyzate medium was examined. The parameter optimization showed that the strain Lactobacillus paracasei 168 can achieve a maximum productivity of 11.8 g/(L h), in batch cultivation on a nutrient enriched MRS medium, at a temperature of 39 °C and a pH value of 6.3. However, this parameter optimum does not correspond to the parameter optimum of lactate yield (96.8 %, T = 30 °C, pH 5.75). In order to define working points for the large‐scale production of lactic acid, parameter combinations which guarantee high values of both lactate productivities (≥ 8 g/(L h)) and lactate yields (≥ 92 %) in a short process duration (≤ 35 h) were predicted by means of three‐dimensional model equations. As a consequence, productivities of 8 g/(L h)–11 g/(L h) with lactate yields of 93–95 % can be achieved with the strain L. paracasei 168. Cultivation on MRS barley hydrolyzate medium resulted in production data with about the same range of values as those obtained with the MRS medium. Under these conditions, this strain accumulated more than 100 g of lactate/L in the medium. Medium optimization experiments showed that the main components of the nitrogen containing nutrients in the MRS medium (peptone and yeast extract) can be replaced by protein extracts from green biomass (lucerne green juice). This positive result for the utilization of different renewable resources in lactic acid fermentation has to be confirmed and optimized for the continuous mode and pilot scale, respectively.
Antimicrobial Evaluation of Endophytic Fungi Inhabiting Medicinal Plants of the Western Ghats of India
Authors: Raviraja N. S. , Maria G. L. , Sridhar K. R.
Published: September 2006

Altogether fifteen species of endophytic fungi were recovered from surface sterilized leaf, stem and bark samples collected from eight medicinal plant species sampled in three different locations of the Western Ghats of India. Ethyl acetate extracts of fermentation cultures of these fungi were tested for the production of antimicrobial compounds using a panel of four bacterial strains and Candida albicans. From fifteen species, eight species of endophytes revealed the production of antimicrobial compounds. Partially purified extracts from solid state fermentation of Alternaria sp., Nigrospora oryzae and Papulospora sp. showed inhibitory activity against both Gram‐positive and Gram‐negative bacteria. In addition, extracts of Alternaria sp., inhibited the growth of Candida albicans. Extracts of Alternaria sp., Nigrospora oryzae and Papulospora sp. are promising enough to deserve further purification and characterization.
Systems Biology Approaches to Bioprocess Development
Authors: Deckwer W.‐D. , Jahn D. , Hempel D. , Zeng A.‐P.
Published: September 2006

Bioinformatic tools can be applied to reconstruct the potential metabolic network of a microorganism from the genome alone. Networks are the rational basis of systems biology. For a systems biology focusing on processes and products, it is a must to functionalize the potential networks. This particularly requires that the phenotype which yields optimal processes and productivities be found out. The functionality of the gene regulatory and the metabolic networks as well can be achieved by the ‘omics' methods. As the functionality depends on the environome, it is essential to apply these techniques coordinatively and possibly simultaneously. Presently, the fluxome (flux distribution of the central metabolic pathways), which has to be determined under variation of genetic properties (metabolic engineering) as well as alterations of the environment, is of particular interest. A process‐oriented systems biology offers manifold tasks for the biochemical engineer, which can only be solved in close cooperation with molecular biologists and bioinformaticians. Among others, engineering is not only responsible for developing defined and reproducible cultivation strategies in highly instrumented bioreactors but also for reliably determining kinetic relationships in dependence on genomic and environmental properties and efficiently performing network simulations. The recognition of influences of engineering parameters on network functionality is only at the beginning.
A general approximate‐state Riemann solver for hyperbolic systems of conservation laws with source terms
Authors: Lhomme Julien , Guinot Vincent
Published: September 2006

An approximate‐state Riemann solver for the solution of hyperbolic systems of conservation laws with source terms is proposed. The formulation is developed under the assumption that the solution is made of rarefaction waves. The solution is determined using the Riemann invariants expressed as functions of the components of the flux vector. This allows the flux vector to be computed directly at the interfaces between the computational cells. The contribution of the source term is taken into account in the governing equations for the Riemann invariants. An application to the water hammer equations and the shallow water equations shows that an appropriate expression of the pressure force at the interface allows the balance with the source terms to be preserved, thus ensuring consistency with the equations to be solved as well as a correct computation of steady‐state flow configurations. Owing to the particular structure of the variable and flux vectors, the expressions of the fluxes are shown to coincide partly with those given by the HLL/HLLC solver. Computational examples show that the approximate‐state solver yields more accurate solutions than the HLL solver in the presence of discontinuous solutions and arbitrary geometries. Copyright © 2006 John Wiley & Sons, Ltd.
Anion channels in astrocytes: Biophysics, pharmacology, and function
Authors: Kimelberg Harold K. , MacVicar Brian A. , Sontheimer Harald
Published: September 2006

The chloride/anion channels that have been so far identified in cultured astrocytes and those that have been confirmed in situ by a combination of mRNA identification, immunocytochemistry, and biophysical studies are reviewed. It is emphasized that we are just beginning to describe such channels and analyze their functions in astrocytes. The best‐studied anion channels studied so far are those known as volume‐regulated anion channels (VRACs). These, as for most channels, have been mainly studied in cultured astrocytes, but some correlative studies have been done in situ, because these channels have been emphasized as release routes for transmitters; namely, excitatory amino acids and ATP. They are activated by cell shape changes and cell swelling, and the release of amino acids and ATP and chloride currents, measured by whole cell clamping, by these processes has been well described, as is also their activation by low concentrations of extracellular ATP. However, the identity of these channels in astrocytes, as in all other cells, remains elusive. The potential involvement of VRACs in pathological states such as stroke, metastasis, and spreading depression is also discussed. © 2006 Wiley‐Liss, Inc.
Pegylated liposomal doxorubicin, melphalan and prednisone therapy for elderly patients with multiple myeloma
Authors: García‐Sanz R , Hernández JM , Sureda A , García‐Laraña J , Prósper F , Alegre A , Bárez A , Mateos MV , San Miguel JF
Published: September 2006

Melphalan & Prednisone (MP) is considered as the standard therapy for Multiple Myeloma (MM) patients not eligible for high‐dose therapy. Here, we report the results of a phase I–II study to evaluate the feasibility and efficacy of the association of PLD to the conventional MP regimen during the first six cycles of the front‐line therapy for untreated MM patients older than 70. Thirty patients were included in the study with a median age of 77 years (71–84) and a M/F ratio of 17/13. The phase I of the study demonstrated that the maximum tolerable dose of PLD in this setting was 30 mg/m2, so it was the final dose evaluated in the study. Twenty‐nine patients were valuable for response, which was: complete in 4 (14%) partial in 15 (52%) minor/no changes in 7 (24%) and progressive in 3 (10%). The median progression free survival (PFS) was 24 months. The median overall survival (OS) has not been reached yet, with a 3‐year probability for OS and PFS of 52 and 37%, respectively. Haematological toxicity was frequent but usually weak/moderate (grades 1 & 2 of the WHO scale) and it was resolved only with dose delays. Infection was a relatively frequent event (30% of patients), but only in 4 cases it was of grade 3. No cases of palmar‐plantar erythrodysesthesia were observed. In conclusion, pegylated liposomal doxorubicin can be safely added to the other chemotherapeutic drugs in the treatment of elderly MM patients, which can be very useful for patients in whom novel agents are not tolerated or inefficient. Copyright © 2006 John Wiley & Sons, Ltd.
cdk5 modulates β‐ and δ‐catenin/Pin1 interactions in neuronal cells
Authors: Muñoz Juan P. , Huichalaf Claudia H. , Orellana Daniel , Maccioni Ricardo B.
Published: September 2006

The cdk5/p35 complex has been implicated in a variety of functions related to brain development, including axonal outgrown and neuronal migration. In this study, by co‐immunoprecipitation and pull‐down experiments, we have shown that the cdk5/p35 complex associates with and phosphorylates the neuronal δ‐catenin. Immunocytochemical studies of δ‐catenin and the cdk5‐activator p35 in primary cortical neurons indicated that these proteins co‐localize in the cell body of neuronal cells. In addition, cdk5 co‐localized with β‐catenin in the cell–cell contacts and plasma membrane of undifferentiated and differentiated N2A cells. In this context, we identified Ser191 and Ser246 on β‐catenin structure as specific phosphorylation sites for cdk5/p35 complex. Moreover, Pin1, a peptidyl–prolyl isomerase (PPIase) directly bound to both, β‐ and δ‐catenin, once they have been phosphorylated by the cdk5/p35 complex. Studies indicate that the cdk5/p35 protein kinase system is directly involved in the regulatory mechanisms of neuronal β‐ and δ‐catenin. J. Cell. Biochem. 100: 738–749, 2007. © 2006 Wiley‐Liss, Inc.
Reducing landslide risk in areas of unplanned housing in the Caribbean—a Government‐Community partnership model
Authors: Anderson Malcolm , Holcombe Liz , Williams Donovan
Published: September 2006

Unplanned housing developments in vulnerable communities on steep tropical and subtropical hillslopes in many developing countries pose major problems for the residents themselves; for Governments, in terms of potential relocation costs; for engineers in determining the precise nature of the hazard and risk; and for donor agencies, such as the World Bank, in establishing the form of disaster mitigation policies that should be promoted. We present a new low‐cost, community‐based approach to landslide risk reduction in such a context. It is founded on the vision that there is often sufficient capacity within Governments to address such landslide issues without needing to incur significant additional costs by employing non‐Government specialist staff. Such expenditure adds to debt and only suboptimally builds within‐country capacity. The approach we present develops a cross‐ministry Government management team, implements a community‐based approach to landslide risk assessment, develops low‐cost interventions through the social intervention fund and builds capacity through community knowledge transfer. We report on the successful pilot undertaken in the Skate Town community, Castries, St. Lucia, West Indies. Copyright © 2006 John Wiley & Sons, Ltd.
Enterotoxigenic Bacillus spp. DNA fingerprint revealed in naturally contaminated nonfat dry milk powder using rep‐PCR
Authors: Cooper Robin M. , McKillip John L.
Published: September 2006

Dry milk powders and functional ingredients frequently contain high levels of viable bacterial spores, some of which may result in growth of toxigenic Bacillus spp. in reconstituted and temperature‐abused foods. Samples from nonfat dry milk (NFDM), infant milk formula (IMF), coffee creamer, lecithin, and cocoa powder were subjected to a short heat treatment followed by enrichment in tryptone phosphate glucose yeast extract (TPGY) broth at 32 °C for 12–25 hours to obtain cell densities of 106 CFU ml–1. DNA was extracted using a modification of established protocol, leading to the development of an optimized method for each food system. Purified DNA was amplified by rep‐PCR using extragenic sequence‐targeting primers and optimized for each food. PCR fingerprints from each food were analyzed electrophoretically for banding patterns earlier correlated to that of enterotoxigenic Bacillus spp. and Bacillus cereus positive control DNA fingerprints. Reverse passive latex agglutination (RPLA) and Bacillus Diarrhoeal Enterotoxin Enzyme Linked Immunosorbent Assay (Tecra Diagnostics) confirmed the presence of HBL and NHE enterotoxin production in NFDM, Coffee creamer, infant milk formula, and two lecithin samples but not in cocoa powder. These results demonstrate the utility of rep‐PCR not only as a tool for bacterial genotyping, but a unique means of quality control and hygiene monitoring in food microbiology. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Use of RNA fingerprinting to identify fungal genes specifically expressed during ectomycorrhizal interaction
Authors: Krause Katrin , Kothe Erika
Published: September 2006

The ecosystem soil is characterized by interactions between microorganisms and plants including mycorrhiza – mutualistic interactions between fungi and plant roots. Species of the basidiomycete genus Tricholoma form ectomycorrhiza with tree roots which is characterized by morphological and metabolic changes of both partners, yet molecular mechanisms of the interaction are poorly understood. We performed differential display with arbitrarily primed RT–PCR using ectomycorrhiza between the basidiomycete Tricholoma vaccinum and its compatible host spruce (Picea abies) to isolate mycorrhiza‐specific fungal gene fragments. 76 differentially expressed PCR fragments were verified and checked for plant or fungal origin and expression pattern. Of 20 fungal fragments with mycorrhiza‐specific expression, sequence analyses were performed to identify homologs with known function of the encoded protein. Among the genes identified were orthologs to an aldehyde dehydrogenase, an alcohol dehydrogenase and a protein of the MATE transporter family, all with possible function in plant pathogen response. A phospholipase B, a β‐glucosidase and a binding protein of basic amino acids might play a role in nutrient exchange and growth in planta. A protein similar to inactive E2 compounds of ubiquitin‐conjugating enzymes like CROC‐1 and MMS2, a Ras protein and an APS kinase were placed in signal transduction and two retrotransposons of the Ty3‐gypsy and the Ty1‐copia family are expressed most likely due to stress. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)