bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulatory role of nucleotides in axonemal function
Authors: Kinoshita Satoko , Miki‐Noumura Taiko , Omoto Charlotte K. 
Published: February 2005

AbstractAxonemal sliding involves both sliding velocity and the extent of sliding, that is how many doublets slide. It is clear that axonemes cannot beat if all doublets were to slide simultaneously, thus sliding extent is important. Using the turbidimetric assay of sliding disintegration of Tetrahymena axonemes, we examined the sliding extent and the effect of ADP, ATP, and ATP analogs on the sliding extent. Of course, ATP is necessary to produce sliding disintegration, but ATP alone did not produce extensive sliding disintegration. The addition of ADP allowed greater extent of sliding disintegration. The additions of higher ATP concentration even in the presence of ADP inhibited sliding disintegration. We also observed sliding disintegration using ribose‐modified ATP analogs, anthraniloylATP, and methylanthraniloylATP. The extent of sliding disintegration was proportional to the analog concentration. Thus in contrast to ATP, higher analog concentration was not inhibitory. These results indicate that high ATP concentration acts to inhibit the extent of sliding disintegration and that ADP relieves this inhibition. We propose a model in which the affinity of multiple cooperative active sites are regulated by binding of ATP or ADP to a regulatory site. This model provides a mechanism by which nucleotides regulate the extent of sliding necessary for effective axonemal bending. © 1995 Wiley‐Liss, Inc.
Deletion of amino acids from the carboxy‐terminal end of actin
Authors: Xia Dong , Peng Isaac 
Published: February 2005

AbstractA series of deletions was made from the C‐terminal end of actin by inserting termination codons into a full length cDNA of human α‐skeletal muscle actin. These included deletions of 2, 3, 10, 20, 30, and 40 amino acids. The cDNA clones were transcribed and the resulting mRNA were translated in vitro using 35S‐labeled methionine. The 35S‐labeled actin and actin mutants were then tested for the ability to coassemble with carrier actin, bind DNAse I, bind myosin S‐1, bind a 27 kDa proteolytic fragment of α‐actinin, and incorporate into myofibrils in vitro. Removal of the C‐terminal two or three amino acids did not grossly alter the properties of actin tested. Deletion of an additional 7 amino acids (10 amino acids total) significantly decreased coassembly, binding to DNAse I, and incorporation into myofibrils, but did not dramatically reduce binding to myosin S‐1 or the 27 kDa fragment of α‐actinin. Deletion of 20 or more amino acids virtually abolished all normal actin function tested. By examining the structure of actin, we propose that the effect of removing residues 356–365 is due to the important role Trp356 plays in maintaining hydrophobic bonds between three non‐contiguous segments of actin. We also suggest that removal of residues 366–372 adversely affected the structure or orientation of the DNAse I binding loop and that this change can account for defects in actin binding to DNAse I, coassembly with wild type actin, and incorporation into myofibrils. © 1995 Wiley‐Liss. Inc.
Over‐expression of smooth muscle caldesmon in mouse fibroblasts
Authors: Surgucheva Irina , Bryan Joseph 
Published: February 2005

AbstractCaldesmon is an actin, calmodulin, tropomyosin, and myosin binding protein implicated in the regulation of actomyosin interactions. We have invesigated the effect of overexpression of the higher molecular weight smooth muscle isoform of caldesmon on mouse L cell physiology. Mouse L(TK−) cell were transfected stably with plasmids carrying the TK+ gene and a full length human smooth muscle caldesmon cDNA under control of the adenovirus major late promoter. Two clones displaying four and eight times the level of the endogenous mouse high molecular weight caldesmon were isolated. These cells acquire a distinct phenotype characterized by an altered morphology, including an increased number of processes and larger area due to enhanced cell spreading, and a significantly slower growth rate than that of untransfected control cells, or cells transfected with the TK+ gene alone. The majority of the overexpressed caldesmon appears to be active and localized on cytoskeleton structures as determined by detergent lysis. Immuno‐fluorescence analysis of the clones revealed that the caldesmon is localized as punctate staining on stress‐fibers and in membrane ruffles. The immunofluores‐cence images suggest that caldesmon overexpressing cells have more total filaments than control cells. The effects of excess caldesmon on cell mobility are ambiguous: one clone displayed increased motility compared to the control, while the motility of the second clone was decreased relative to the control. © 1995 Wiley‐Liss, Inc.
Analysis of the interdependent localization of vimentin and microtubules in neoplastic myoepithelial cells
Authors: Jaeger Ruy G. , Jaeger Márcia M. M. , Araújo Vera C. , Kachar Bechara 
Published: February 2005

AbstractSalivary gland neoplastic myoepithelial cells in culture form very thin cytoplasmic processes in which the vimentin network is well dispersed. These vimentin filaments can be individually visualized by immunofluorescence. In this study, we have analyzed the role of microtubules in the distension and organization of the vimentin filament network found in these cells. We find that vimentin filaments colocalize along microtubules; however, a significant number of filaments can also be found in microtubule‐free domains. Additionally, vimentin filaments are absent from large domains of microtubule inhibitor nocodazole did not cause any retraction of the distended vimentin network. This observation suggests that the structural integrity of microtubules is not important for the stability of the vimentin network. Combining procedures for transient disruption of vimentin filaments and microtubules we observed that, in the absence of microtubules, the vimentin network could reassemble in the perinuclear region but was unable to extend toward the cell periphery. The dispersion of vimentin filaments to the peripheral regions of the cytoplasm could only be observed upon microtubule reassembly. This indicates that microtubules are not required for the stability of the vimentin network, but the dispersion of vimentin filaments to the peripheral cytoplasm depends on active interactions with microtubules. © 1995 Wiley‐Liss, Inc.
Microtubule‐associated movement of mitochondria and small particles in Acanthamoeba castellanii
Authors: Baumann Otto , Murphy Douglas B. 
Published: February 2005

AbstractUsing video‐enhanced differential interference microscopy and digital image processing, we have observed organelle motility in Acanthamoeba castellanii. In amoebae taken from cultures in rapid growth phase, mitochondria and small particles moved over distances of several microns and at an average velocity of ∼2 μ/s. Mitochondrial motility was verified by intensified fluorescence microscopy of cells that were labeled in vivo with the DNA‐binding dye DAPI or the mitochondria‐specific dye Mito Tracker. We further studied the role of microtubules (MTs) in the translocation of cell organelles. Double‐labelling of fixed cells bules with mitochondrial markers (anti‐F1β antibody, Mito Tracker) and cytoskeletal markers (anti‐tubulin antibody, rhodamine‐phalloidin) demonstrate that the mitochondria colocalize with MTs in the subcortical cell area and are excluded from the F‐actin‐rich cell cortex. Colchicine treatment resluted in an almost complete depolymerization of MTs and an inhibition of organelle motility. Moreover, we have directly visualized MTs in vivo in flattened amoebae. Mitochondria and small particles moved along the MTs in a bidirectional mode at an average velocity of ∼1 μm/s. We conclude that the observed movement of mitochondria and small particles in Acanthamoeba castellanii mainly occurs via microtubules and associated motor proteins. © 1995 Wiley‐Liss, Inc.
Vinculin localization and actin stress fibers differ in thyroid cells organized as monolayers or follicles
Authors: Yap Alpha S. , Stevenson Bruce R. , Waters Michael J. , Keast Janet R. , Manley Simon W. 
Published: February 2005

AbstractIn epithelial cells interactions between the actin cytoskeleton and cell‐cell junctions regulate paracellular permeability and partcipate in morphogenesis. We have studied the relationship between supracellular morphology and actin‐junction interactions using primary cultures of porcine thyroid cells grown either as three‐dimensional follicles or as open monolayers. Regardless of morphology, thyroid cells assembled occluding and adhesive junctions containing ZO‐1 and E‐cadherin, respectively, and showed F‐actin staining in apical microvilli and a perijunctional ring. In monolayers, actin stress fibers were also observed in the apical and basal poles of cells, where they terminated in the vinculin‐rich zonula adherens and in cell‐substrate focal adhesions, respectively. Surprisingly, we were unable to detect vinculin localization in follicular cells, which also did not form stress fibers. Immunoblotting confirmed significantly greater vinculin in triton‐insoluble fractions from monolayer cells compared with follicular cells. Incubation of monolayers with 8 chloro(phenylthio)‐cyclic AMP decreased the level of immunodetectable vinculin in the zonula adherens, indicating that junctional incorporation of vinculin was regulated by cyclic AMP. In monolayer cultures, cytochalasin D (1 μM) caused actin filaments to aggregate associated with retraction of cells from one another and the disruption of cell junctions. Despite morphologically similar perturbations of actin organization in follicular cultures treated with cytochalasin D, junctional staining of ZO‐1 and E‐cadherin was preserved and cells remained adherent to one another. We conclude that in cultured thyroid cells structural and functional associations between actin filaments and cellular junctions differ depending upon the supracellular morphology in which cells are grown. One important underlying mechanism appears to be regulation of vinculin incorporation into adhesive junctions by cyclic AMP. © 1995 Wiley‐Liss, Inc.
Studies on spontaneous formation of 1D nanocrystals of silicon carbide
Authors: Huczko A. , Lange H. , Bystrzejewski M. , Rűmmeli M. H. , Gemming T. , Cudziło S. 
Published: February 2005

AbstractNovel nanostructures have been formed spontaneously during the thermolysis of mixtures containing halogenohydrocarbons and Si‐related compounds as a reducing agent in a calorimetric bomb. Elemental analysis, XRD (X‐Ray Diffraction), EELS (Electron Energy Loss Spectroscopy), EDX (Energy Disspersive X‐ray spectroscopy), IR (InfraRed spectroscopy), Raman spectroscopy, HR SEM (High Resolution Scanning Electron Spectroscopy) and TEM (Transmission Electron Spectroscopy) were used to determine the chemical composition and structural features of the products. They contain well‐crystallized elongated 1D single crystals of SiC nanofibres, coated with a thin SiO2 amorphous layer, and crystallized carbon nanoparticles. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of olivine single crystals by the micro‐pulling‐down method
Authors: Ganschow S. , Klimm D. 
Published: February 2005

AbstractOlivine, (Mg1‐xFex)2SiO4, crystals have been grown by the micro‐pulling‐down method. The crystals consisted of a homogeneous core and a surrounding peripheral rim with increased fayalite concentration and numerous second phase inclusions, mainly magnetite. The formation of magnetite could be successfully retarded by using an adapted atmosphere consisting of 5 vol% CO + 10 vol% CO2 + 85 vol% Ar. This mixture yields an oxygen pressure well inside the predominance field of FeO over a wide temperature range. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal growth features and properties of layered rare earth and barium cobaltates
Authors: Bychkov G. L. , Shiryaev S. V. , Soldatov A. G. , Shestak A. S. , Barilo S. N. , Sheptyakov D. V. , Conder K. , Pomjakushina E. , Podlesnyak A. , Furrer A. , Bruetsch R. 
Published: February 2005

AbstractHigh quality single crystals of LnBaCo2O5+δ (0 < δ < 1) (Ln = Pr, Eu, Gd, Tb, Dy) with rectangular shape and average dimensions 5 mm × 5 mm × 1 mm were grown for the first time from overstoichiometric flux melt. The data on the primary crystallization field of most cobaltate phases, which appear in parts of corresponding Gibbs triangles in the range 1373 – 1523 K are discussed. Bulk single crystals of new phases HoBaCo4O7 up to 300 mm3, YBaCo4O7 and TbBaCo4O7 up to 10 mm3 in volume were grown first. A solution of these compounds structure has been found in the space group P63mc. For the Ln = Pr, Gd, Sm, Tb, Dy, Ho based systems under the liquidus line there are several other new cobaltate phases of both perovskite, and hexagonal crystal structure. Stability of the double perovskite phase and temperature of the antiferromagnetic – ferromagnetic phase transition in relation to the radius of rare earth ions are compared. The data on the exact analysis of chemical composition, including EDX and iodometric titration, as well as results on magnetic susceptibility of EuBaCo1‐xAlxO5+δ (0 < x < 0.3) are discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis, single crystal growth and thermodynamic properties of SrNdAlO4–CaNdAlO4 solid solutions
Authors: Novoselov A. , Ryumin M. , Pushkina G. , Spiridonov F. , Zimina G. , Komissarova L. , Pajaczkowska A. 
Published: February 2005

AbstractContinuous solid solutions in the SrNdAlO4–CaNdAlO4 system are formed. Powder samples of SrxCa1‐xNdAlO4 (0.0 ≤ x ≤ 1.0) were obtained using the carbonate coprecipitation method while single crystals of SrxCa1‐xNdAlO4 (x = 0.0, 0.162, 0.392, 0.687, 1.0) were grown by the Czochralski method. Structural parameters and thermodynamic properties of the samples were studied by X‐ray diffraction and heat flux Calvet calorimetry. Composition dependence of lattice constants was observed to follow Vegard's low. Heat of solution of the SrxCa1‐xNdAlO4 samples in molten 2PbO·B2O3 were measured, and enthalpies of formation and mixing were calculated. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bridgman‐Stockbarger growth and X‐ray photoelectron spectroscopy study of LiY1‐xEuxF4 crystals
Authors: Maślankiewicz P. , Szade J. , Winiarski A. , Daniel Ph. 
Published: February 2005

AbstractLiY1‐xEuxF4 (x = 0; 0.1 nominally) crystals were obtained by a modified Bridgman‐Stockbarger technique. Europium was found to coexist in the LiYF4:Eu crystal in two valence states, Eu3+ and Eu2+, the content of the latter being enhanced in the near‐to‐surface region. The presence of bulk divalent europium is attributed to a partial reduction of europium during crystal growth. Because of the presence of Eu2+, additional electronic states in the electronic gap of LiYF4 were observed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Properties of ZrN films as substrate masks in liquid phase epitaxial lateral overgrowth of compound semiconductors
Authors: Dobosz D. , Golaszewska K. , Zytkiewicz Z. R. , Kaminska E. , Piotrowska A. , Piotrowski T. T. , Barcz A. , Jakiela R. 
Published: February 2005

AbstractThe usefulness of ZrN films as masks for epitaxial lateral overgrowth of GaAs and GaSb by liquid phase epitaxy is studied. It was observed that during the growth process ZrN masks are mechanically stable, they adhere strongly to the substrate and do not show any signs of degradation even at the growth temperature as high as 750 °C. Moreover, perfect selectivity of GaAs and GaSb epitaxy was obtained on ZrN masked substrates ensuring the growth wide and thin layers. To study the influence of growth conditions on electrical resistivity of the mask, ZrN films deposited on GaAs substrates were annealed in various atmospheres. It was found that at temperatures higher than about 580 °C the ZrN masks become highly resistive when heat‐treated in hydrogen flow employed during growth. Usually, LPE growth temperature for GaAs is higher. Thus, ELO growth of GaAs by LPE becomes more difficult, though still possible, if ZrN masks are to be applied as buried electrical contacts. For GaSb ELO layers however, typical LPE growth temperature is about 480 °C. This allows us to grow high quality GaSb ELO layers by LPE still preserving high electrical conductivity of ZrN mask. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Regenerative and predictive medicine of cardiovascular disease: The 9th Leipziger workshop and the 2nd international workshop on slide based cytometry
Authors: Lenz Dominik , Barten Markus J. , Hiller Sabine , Tárnok Attila , Sack Ulrich 
Published: February 2005

AbstractSlide‐based cytometry (SBC) and related techniques offer unique tools to perform complex immunophenotyping, thereby enabling diagnostic procedures at very early disease stages. Multicolor or polychromatic analysis of cells by SBC is of special importance, not only as a cytomics technology platform but also for patients with low blood volume such as neonates. The exact knowledge of the location of each cell on the slide allows restaining and subsequent reanalysis of the specimen. These separate measurements of the same specimen can be fused to one data file (merging), thus increasing the information obtained per cell. Relocalization and optical evaluation of the cells, a feature typical of SBC, can be of integral importance for cytometric analysis. Due to this feature, artifacts can be excluded and morphology of measured cells can be documented. Predictive medicine aims at the detection of changes in patient's state before the manifestation of the disease or its complications. Such instances concern multiorgan failure in sepsis or noninfectious posttraumatic shock in intensive care patients or the pretherapeutic identification of high‐risk patients undergoing cancer cytostatic therapy. Early anti‐infectious or antishock therapy and curative chemotherapy in combination with stem cell transplantation may provide better chances of patients' survival at concomitant cost containment. Predictive medicine that guides early individualized decrease or cessation of therapy may lower or abrogate potential therapeutic side effects (individualized medicine). Regenerative medicine concerns patients who have diseased and injured organs and may be treated with transplanted organs. However, there is a severe shortage of donor organs that is worsening yearly given the aging population. Regenerative medicine and tissue engineering apply the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Neovascularization is promoted by bone marrow–derived endothelial progenitor cells that lead to the formation of entirely new vessels into ischemic tissue. With this knowledge, many therapeutical borders can be skipped. Diseases formerly uncontrolled can be corrected with stem cells to provide causal healing with regeneration processes. The 9th Leipziger Workshop combined with the 2nd International Workshop on SBC aimed to offer new methods in image cytometry and SBC for solutions in clinical research. It moved toward practical applications in clinics and the clinical laboratory. This development will be continued in 2005 at the upcoming Leipziger Workshop and the 3rd International Workshop on SBC. © 2005 Wiley‐Liss, Inc.
Passive responses of young guinea pigs during exposure to a novel environment: Influences of social partners and age
Authors: Hennessy Michael B. , Morris Angela 
Published: February 2005

AbstractGuinea pig pups exhibit a two‐stage, active/passive response during isolation in a novel environment that resembles the “protest” and “despair” stages observed in some species of primates. The present study examined social and developmental influences on the expression of the passive stage of responsiveness in young guinea pigs. Both preweaning and periadolescent guinea pigs displayed the passive stage during isolation in a novel environment. In preweaning pups and periadolescents that had been housed with the mother since birth, the presence of the mother in the novel environment prevented the passive stage from occurring. Levels of passive responses in the presence of an unfamiliar adult female were generally intermediate to those in the other two test conditions; however, periadolescents housed only with a peer between weaning and testing exhibited the passive stage of responsiveness not only when alone but also when with the mother or an unfamiliar female. The findings indicate that the passive responses can occur in periadolescent guinea pigs and that the test conditions under which they occur depend upon the periadolescents' social housing conditions prior to testing. Further, the results are consistent with the hypothesis that responses during the second stage constitute “stress‐induced sickness behaviors.” © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46: 86–96, 2005.
Cardiac reactivity is associated with changes in negative emotion in 24‐month‐olds
Authors: Buss Kristin A. , Hill Goldsmith H. , Davidson Richard J. 
Published: February 2005

AbstractDespite the call for multilevel observation of negative affect, including multiple physiological systems, too little empirical research has been conducted in infants and young children, and physiology–affect associations are not consistently reported. We examined changes in heart rate, respiratory sinus arrhythmia, and preejection period in 24‐month‐olds across four increasingly challenging, emotion‐eliciting tasks. We predicted that changes in cardiac reactivity would be systematically related to changes in negative affect. Results largely support the predictions with one important exception. With increasing distress across the tasks, HR increased and RSA decreased. However, no significant changes in PEP were observed. HR was associated with negative affect during all tasks, and changes in HR were related to changes in negative affect. PEP and negative affect were associated, but only marginally so. Within‐subject analyses confirmed the predicted associations. Finally, the associations between physiology and negative affect were different for boys and girls. We discuss these results in the context of implications for future research on cardiac–affect associations in young children. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46: 118–132, 2005.
Mild Protocols for Generating Molecular Complexity: A Comparative Study of Hetero‐Domino Reactions Based on the Oxidant and the Substitution Pattern
Authors: Candela Lena José I. , Sánchez Fernández Elena M. , Ramani Alwar , Birlirakis Nicolas , Barrero Alejandro F. , Arseniyadis Siméon 
Published: February 2005

AbstractA bicyclic unsaturated 1,2‐diol framework was found to undergo an interesting set of domino reactions on treatment with oxidants. One‐pot syntheses of seven‐membered‐ring‐containing frameworks were achieved by a Pb(OAc)4‐mediated domino process, while with other oxidants investigated, such as Mn(OAc)3, Dess–Martin periodinane, PhI(OAc)2, Ph3Bi(CO)3, NaIO4, and NaBiO3, the domino process was interrupted halfway through. Finally, tetrapropylammonium perruthenate (TPAP‐NMO), Pd(OAc)2, pyridinium dichromate (PDC), and pyridinium chlorochromate (PCC) gave only allylic oxidation and further diketone formation without any of the bond cleavage that is necessary to initiate the domino process. The substrates were chosen to test the limits of reactivity of various unsaturated 1,2‐diol derivatives and to provide guidelines for their use in constructing complex synthetic targets. In this article we provide details of the reaction conditions, preparation of the starting materials and characterization of the products, along with new, unpublished results. Information is assembled to facilitate comparison between the various oxidants, solvents and substitution patterns. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)