bluuebunny/crossref_metadata_2025_split huggingface dataset:
Colour constancy in diurnal and nocturnal hawkmoths
Authors: Balkenius Anna , Kelber Almut 
Published: August 2004

SUMMARY
Diurnal and nocturnal hawkmoths have been shown to use colour vision for flower discrimination. Here, we present evidence that the nocturnal hawkmoth Deilephila elpenor and the diurnal hawkmoth Macroglossum stellatarum also have colour constancy. Colour constancy was shown in D. elpenor in two multiple-choice experiments with five different bluish colour patches under white and blue illumination and with five yellowish colour patches under white, blue and yellow illumination. The mechanism underlying colour constancy in both species was investigated in two dual-choice experiments. The choice behaviour is consistent with the use of the von Kries coefficient law. Although the moths have colour constancy, they react to the colour of the illumination. They make fewer choices when tested under the changed illumination, where they never receive a reward, compared with the training illumination. Even if colour constancy can be explained by a von Kries adaptation mechanism, the fact that the animals discriminate between different illuminations indicates that some additional process must be involved.
Navigation in wood ants Formica japonica: context dependent use of landmarks
Authors: Fukushi Tsukasa , Wehner Rüdiger 
Published: August 2004

SUMMARY
Wood ants Formica japonica can steer their outbound (foraging) and inbound (homing) courses without using celestial compass information, by relying exclusively on landmark cues. This is shown by training ants to run back and forth between the nest and an artificial feeder, and later displacing the trained ants either from the nest (when starting their foraging runs:outbound full-vector ants) or from the feeder (when starting their home runs:inbound full-vector ants) to various nearby release sites. In addition, ants that have already completed their foraging and homing runs are displaced after arrival either at the feeder (outbound zero-vector ants) or at the nest(inbound zero-vector ants), respectively, to the very same release sites. Upon release, the full-vector ants steer their straight courses by referring to panoramic landmark cues, while the zero-vector ants presented with the very same visual scenery immediately search for local landmark cues defining their final goal. Hence, it depends on the context, in this case on the state of the forager's round-trip cycle, what visual cues are picked out from a given set of landmarks and used for navigation.
Novel Palladium Catalyst Supported on GaAs(001) Passivated by Ammonium Sulfide
Authors: Takamiya Ikuko , Tsukamoto Shiro , Shimoda Masahiko , Miyashita Naoki , Arisawa Mitsuhiro , Arakawa Yasuhiko , Nishida Atsushi 
Published: August 2004

Abstract
A more reactive palladium catalyst than homogeneous Pd(PPh3)4 catalyst for the Heck reaction supported on a sulfur-terminated GaAs(001) plate was developed. Sulfur termination using (NH4)2Sx at 60 °C and Pd absorption in acetonitrile at 100 °C is essential for the preparation of an active and stable catalyst. The catalyst could be reused in this reaction up to ten times.
High Stability in Organic Solvent of Heme Proteins Immobilized in the Interlayers of Magadiite Nanoparticles
Authors: Peng Shuge , Gao Qiuming , Shi Jianlin 
Published: August 2004

Abstract
Enzymatic activities of heme proteins, myoglobin (Mb) and hemoglobin (Hb), immobilized in the interlayers of magadiite nanoparticles under mild condition, toward the oxidation of o-phenylenediamine (OPD) in an organic solvent were firstly reported. The immobilized heme proteins showed higher stability than that of free Mb and Hb in organic toluene solution.
The First Enantiomerically Pure Synthesis of (S)- and (R)-Naftopidil Utilizing Hydrolytic Kinetic Resolution of (±)-(α-Naphthyl) Glycidyl Ether
Authors: Kothakonda Kiran Kumar , Bose D Subhas 
Published: August 2004

Abstract
Hydrolytic Kinetic Resolution (HKR) of (±)-(α-Naphthyl) glycidyl ether with (R,R)-salen Co(III) OAc complex provided enatiomerically pure (S)-naphthyl glycidyl ether and (R)-1-naphthyl glycerol; opening of the corresponding pure terminal epoxide with 1-(2-methoxyphenyl)piperizine gave the enantiomerically pure (S)- and (R)-Naftopidil.
Synthesis of Novel Organic–Inorganic Hybrid Cages via Cobalt-catalyzed Cyclotrimerization of Dimethylethynylsilyl Groups on a Silsesquioxane
Authors: Wada Kenji , Yamasaki Takuro , Kondo Teruyuki , Mitsudo Take-aki 
Published: August 2004

Abstract
Novel organic–inorganic hybrid cages composed of a half-caged silsesquioxane skeleton and a benzene ring have been synthesized by cobalt-catalyzed intramolecular cyclotrimerization of a silsesquioxane bearing three dimethylethynylsilyl groups.
Multiplexed Genetic Analysis Using an Expanded Genetic Alphabet
Authors: Johnson Scott C , Marshall David J , Harms Gerda , Miller Christie M , Sherrill Christopher B , Beaty Edward L , Lederer Scott A , Roesch Eric B , Madsen Gary , Hoffman Gary L , Laessig Ronald H , Kopish Greg J , Baker Mei Wang , Benner Steven A , Farrell Philip M , Prudent James R 
Published: August 2004

AbstractBackground: All states require some kind of testing for newborns, but the policies are far from standardized. In some states, newborn screening may include genetic tests for a wide range of targets, but the costs and complexities of the newer genetic tests inhibit expansion of newborn screening. We describe the development and technical evaluation of a multiplex platform that may foster increased newborn genetic screening.Methods: MultiCode® PLx involves three major steps: PCR, target-specific extension, and liquid chip decoding. Each step is performed in the same reaction vessel, and the test is completed in ∼3 h. For site-specific labeling and room-temperature decoding, we use an additional base pair constructed from isoguanosine and isocytidine. We used the method to test for mutations within the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The developed test was performed manually and by automated liquid handling. Initially, 225 samples with a range of genotypes were tested retrospectively with the method. A prospective study used samples from &gt;400 newborns.Results: In the retrospective study, 99.1% of samples were correctly genotyped with no incorrect calls made. In the perspective study, 95% of the samples were correctly genotyped for all targets, and there were no incorrect calls.Conclusions: The unique genetic multiplexing platform was successfully able to test for 31 targets within the CFTR gene and provides accurate genotype assignments in a clinical setting.
Screening for Serum Total Homocysteine in Newborn Children
Authors: Refsum Helga , Grindflek Anne W , Ueland Per M , Fredriksen Åse , Meyer Klaus , Ulvik Arve , Guttormsen Anne B , Iversen Ole E , Schneede Jørn , Kase Bengt F 
Published: August 2004

AbstractBackground: Newborn screening for total homocysteine (tHcy) in blood may identify babies with vitamin B12 (B12) deficiency or homocystinuria, but data on the causes of increased tHcy in screening samples are sparse.Methods: Serum concentrations of tHcy, cystathionine, methionine, folate, and B12 and the methylenetetrahydrofolate reductase (MTHFR) 677C&gt;T polymorphism were determined in 4992 capillary blood samples collected as part of the routine screening program in newborn children. Methylmalonic acid (MMA), gender (SRY genotyping), and the frequency of six cystathionine β-synthase (CBS) mutations were determined in 20–27% of the samples, including all samples with tHcy &gt;15 μmol/L (n = 127), B12 &lt;100 pmol/L (n = 159), or methionine &gt;40 μmol/L (n = 154).Results: The median (5th–95th percentile) tHcy concentration was 6.8 (4.2–12.8) μmol/L. B12 status, as determined by serum concentrations of B12, tHcy, and MMA, was moderately better in boys than in girls. tHcy concentrations between 10 and 20 μmol/L were often associated with low B12, whereas tHcy &gt;20 μmol/L (n = 43) was nearly always explained by increased methionine. tHcy did not differ according to folate concentrations or MTHFR 677C&gt;T genotypes. None of the babies had definite CBS deficiencies, but heterozygosity led to low cystathionine, increased methionine, but normal tHcy concentrations.Conclusion: Increased tHcy is a common but not specific finding in newborns. The metabolite and vitamin profiles will point to the cause of hyperhomocysteinemia. Screening for tHcy and related factors should be further evaluated in regions with high prevalence of homocystinuria and in babies at high risk of B12 deficiency.
Miniaturized Multiplex Label-Free Electronic Chip for Rapid Nucleic Acid Analysis Based on Carbon Nanotube Nanoelectrode Arrays
Authors: Koehne Jessica E , Chen Hua , Cassell Alan M , Ye Qi , Han Jie , Meyyappan Meyya , Li Jun 
Published: August 2004

Abstract
Background: Reducing cost and time is the major concern in clinical diagnostics, particularly in molecular diagnostics. Miniaturization technologies have been recognized as promising solutions to provide low-cost microchips for diagnostics. With the recent advancement in nanotechnologies, it is possible to further improve detection sensitivity and simplify sample preparation by incorporating nanoscale elements in diagnostics devices. A fusion of micro- and nanotechnologies with biology has great potential for the development of low-cost disposable chips for rapid molecular analysis that can be carried out with simple handheld devices.
Approach: Vertically aligned multiwalled carbon nanotubes (MWNTs) are fabricated on predeposited microelectrode pads and encapsulated in SiO2 dielectrics with only the very end exposed at the surface to form an inlaid nanoelectrode array (NEA). The NEA is used to collect the electrochemical signal associated with the target molecules binding to the probe molecules, which are covalently attached to the end of the MWNTs.
Content: A 3 × 3 microelectrode array is presented to demonstrate the miniaturization and multiplexing capability. A randomly distributed MWNT NEA is fabricated on each microelectrode pad. Selective functionalization of the MWNT end with a specific oligonucleotide probe and passivation of the SiO2 surface with ethylene glycol moieties are discussed. Ru(bpy)2+-mediator-amplified guanine oxidation is used to directly measure the electrochemical signal associated with target molecules.
Summary: The discussed MWNT NEAs have ultrahigh sensitivity in direct electrochemical detection of guanine bases in the nucleic acid target. Fewer than ∼1000 target nucleic acid molecules can be measured with a single microelectrode pad of ∼20 × 20 μm2, which approaches the detection limit of laser scanners in fluorescence-based DNA microarray techniques. MWNT NEAs can be easily integrated with microelectronic circuitry and microfluidics for development of a fully automated system for rapid molecular analysis with minimum cost.
Maternal Serum Invasive Trophoblast Antigen (Hyperglycosylated hCG) as a Screening Marker for Down Syndrome during the Second Trimester
Authors: Palomaki Glenn E , Neveux Louis M , Knight George J , Haddow James E , Pandian Raj 
Published: August 2004

Abstract
Background: Approximately two million pregnancies in the United States are screened for Down syndrome annually by use of second-trimester maternal serum markers. At present, a combination of four markers can identify 75% of affected pregnancies when 5% of screened women are classified as candidates for amniocentesis. Although not currently included in screening panels, invasive trophoblast antigen (ITA) is a promising screening marker in serum or urine in both the second and first trimesters. This study aims at better defining the screening performance of serum ITA in the second trimester.
Methods: In an earlier study, serum samples from an unbiased sampling of 45 Down syndrome (cases) and 238 unaffected (control) pregnancies between 14 and 20 weeks of gestation were collected from various centers in the United States. Samples were aliquoted and stored at −20 °C for 8 years. We measured ITA in these samples and determined the screening performance both univariately and in combination with other screening markers.
Results: The median ITA in Down syndrome pregnancies was &gt;3.00 multiples of the median, higher than that found for human chorionic gonadotropin (hCG) or free β-hCG. At a 5% false-positive rate, ITA univariately detected 38% and 40% of Down syndrome pregnancies, respectively, when assigned by date of last menstrual period or ultrasound date. Modeling yielded rates of 45% and 48%. ITA correlated strongly with hCG and free β-hCG. When substituted for either of these in a multiple marker panel, ITA performed comparably.
Conclusions: This study indicates that serum ITA is an effective marker for Down syndrome. It is highly correlated with both hCG and free β-hCG and could replace either of them in a multiple marker panel.
Functional studies on the ligand-binding domain of Ultraspiracle from Drosophila melanogaster
Authors: Przibilla S. , Hitchcock W. W. , Szécsi M. , Grebe M. , Beatty J. , Henrich V. C. , Spindler-Barth M. 
Published: August 2004

AbstractThe functional insect ecdysteroid receptor is comprised of the ecdysone receptor (EcR) and Ultraspiracle (USP). The ligand-binding domain (LBD) of USP was fused to the GAL4 DNA-binding domain (GAL4-DBD) and characterized by analyzing the effect of site-directed mutations in the LBD. Normal and mutant proteins were tested for ligand and DNA binding, dimerization, and their ability to induce gene expression. The presence of helix 12 proved to be essential for DNA binding and was necessary to confer efficient ecdysteroid binding to the heterodimer with the EcR (LBD), but did not influence dimerization. The antagonistic position of helix 12 is indispensible for interaction between the fusion protein and DNA, whereas hormone binding to the EcR (LBD) was only partially reduced if fixation of helix 12 was disturbed. The mutation of amino acids, which presumably bind to a fatty acid evoked a profound negative influence on transactivation ability, although enhanced transactivation potency and ligand binding to the ecdysteroid receptor was impaired to varying degrees by mutation of these residues. Mutations of one fatty acidbinding residue within the ligand-binding pocket, I323, however, evoked enhanced transactivation. The results confirmed that the LBD of Ultraspiracle modifies ecdysteroid receptor function through intermolecular interactions and demonstrated that the ligand-binding pocket of USP modifies the DNA-binding and transactivation abilities of the fusion protein.
Monitoring human parvovirus B19 virus-like particles and antibody complexes in solution by fluorescence correlation spectroscopy
Authors: Toivola J. , Michel P. O. , Gilbert L. , Lahtinen T. , Marjomäki V. , Hedman K. , Vuento M. , Oker-Blom C. 
Published: August 2004

AbstractFluorescence correlation spectroscopy (FCS) was used in monitoring human parvovirus B19 virus-like particle (VLP) antibody complexes from acute phase and pastimmunity serum samples. The Oregon Green 488-labeled VLPs gave an average diffusion coefficient of 1.7x10exp-7 cm(2)s(-1) with an apparent hydrodynamic radius of 14 nm. After incubation of the fluorescent VLPs with an acute phase serum sample, the mobility information obtained from the fluorescence intensity fluctuation by autocorrelation analysis showed an average diffusion coefficient of 1.5x10exp-8 cm(2)s(-1), corresponding to an average radius of 157 nm. In contrast, incubation of the fluorescent VLPs with a pastimmunity serum sample gave an average diffusion coefficient of 3.5x10exp-8 cm(2)s(-1) and a radius of 69 nm. A control serum devoid of B19 antibodies caused a change in the diffusion coefficient from 1.7x10exp-7 to 1.6x10exp-7 cm(2)s(-1), which is much smaller than that observed with acute phase or pastimmunity sera. Thus, VLP-antibody complexes with different diffusion coefficients could be identified for the acute phase and pastimmunity sera. FCS measurement of VLPimmune complexes could be useful in distinguishing between antibodies present in acute phase or past-immunity sera as well as in titration of the VLPs.
The Btk inhibitor LFM-A13 is a potent inhibitor of Jak2 kinase activity
Authors: Akker E. van den , Dijk T.B. van , Schmidt U. , Felida L. , Beug H. , Löwenberg B. , Lindern M. von 
Published: August 2004

AbstractLFMA13, or α-cyano-β-hydroxy-β-methyl-N-(2,5-dibromophenyl)propenamide, was shown to inhibit Brutons tyrosine kinase (Btk). Here we show that LFM-A13 efficiently inhibits erythropoietin (Epo)-induced phosphorylation of the erythropoietin receptor, Janus kinase 2 (Jak2) and downstream signalling molecules. However, the tyrosine kinase activity of immunoprecipitated or in vitro translated Btk and Jak2 was equally inhibited by LFM-A13 in in vitro kinase assays. Finally, Epo-induced signal transduction was also inhibited in cells lacking Btk. Taken together, we conclude that LFM-A13 is a potent inhibitor of Jak2 and cannot be used as a specific tyrosine kinase inhibitor to study the role of Btk in Jak2-dependent cytokine signalling.
Proteinases participating in the processing and activation of prolegumain in primary cultured rat macrophages
Authors: Lecaille F. , Muno D. , Kominami E. , Ishidoh K. 
Published: August 2004

AbstractThe mammalian legumain is a recently identified lysosomal cysteine proteinase belonging to the clan CD and homologous to plant legumain. This enzyme has the characteristic of specifically hydrolyzing peptide bonds after asparagine residues. As in the case of papain-type cysteine proteinases, legumain is synthesized as an inactive zymogen, and processed into a mature form localized in lysosomes. However, the mechanism of its activation remains unclear. In this study, we analyze which types of proteinases may participate in the processing of legumain in rat primary cultured macrophages using various proteinase inhibitors after 24 h treatment with Bafilomycin A1, a vacuolar ATPase inhibitor. The processing of legumain in macrophages was accomplished by papain-type cysteine proteinases other than cathepsin B.
Characterisation of a highly specific, endogenous inhibitor of cysteine protease from Staphylococcus epidermidis, a new member of the staphostatin family
Authors: Dubin G. , Stec-Niemczyk J. , Dylag T. , Silberring J. , Dubin A. , Potempa J. 
Published: August 2004

AbstractStaphostatins, a novel family of cysteine protease inhibitors with a unique mechanism of action and distinct protein fold has recently been discovered. In this report we describe the properties ofStaphylococcus epidermidisstaphostatin A (EcpB), a new member of the family. As for other staphostatins, the recombinantS. epidermidisstaphostatin A exerted very narrow inhibitory specificity, limited to cysteine protease from the same species. The closely related proteases fromS. aureuscleaved the inhibitor at the reactive site peptide bond and inactivated it. The EcpB homologue,S. aureusstaphostatin A (ScpB), was also susceptible to proteolytic cleavage at the same site by nontarget cysteine proteases. Conversely,S. aureusstaphostatin B (SspC) was resistant to such proteolysis. The difference in the susceptibility of individual inhibitors to proteolytic cleavage at the reactive site suggests subtle variations in the mechanism of interaction with cysteine proteases.
Metalloproteases with EGF, CUB, and thrombospondin-1 domains function in molting of Caenorhabditis elegans
Authors: Suzuki M. , Sagoh N. , Iwasaki H. , Inoue H. , Takahashi K. 
Published: August 2004

AbstractFunctional analysis using RNAi was performed on eleven genes for metalloproteases of the M12A family inCaenorhabditis elegansand the interference of the C17G1.6 gene (nas-37) was found to cause incomplete molting. The RNAi of the C26C6.3 gene (nas-36) also caused a similar molting defect but not so severely as that of the nas-37 gene. Both the genes encode an astacinlike metalloprotease with an epidermal growth factor (EGF) like domain, a CUB domain, and a thrombospondin-1 domain, in this order. The promoterdriven green fluorescent protein (GFP) expression analysis suggested that they are expressed in hypodermal cells throughout the larval stages and in the vulva of adult animals. In the genetic background of rde-1(ne219), where RNAi does not work, the molting defect caused by the nas-37 interference was observed when the transgenic wildtype rde-1 gene was expressed under the control of the dpy-7 promoter, known to be active in the hypodermal cells, but not under the control of the myo-3 promoter, active in the muscular cells. Therefore these proteases are thought to be secreted by the hypodermal cells and to participate in shedding of old cuticles.
Regulation of gene expression by α-tocopherol
Authors: Azzi A. , Gysin R. , Kempná P. , Munteanu A. , Villacorta L. , Visarius T. , Zingg J.-M. 
Published: August 2004

AbstractSeveral genes are regulated by tocopherols which can be categorized, based on their function, into five groups: genes that are involved in the uptake and degradation of tocopherols (Group 1) include α-tocopherol transfer protein (α-TTP) and cytochrome P450 (CYP3A); genes that are associated with lipid uptake and atherosclerosis (Group 2) include CD36, SRBI and SRAI/II. Genes that modulate the expression of extracellular proteins (Group 3) include tropomyosin, collagenα1, MMP-1, MMP-19 and connective tissue growth factor (CTGF). Genes that are related to inflammation, cell adhesion and platelet aggregation (Group 4) include Eselectin, ICAM-1, integrins, glycoprotein IIb, Il-2, IL-4 and IL-β. Group 5 comprises genes coding for proteins involved in cell signaling and cell cycle regulation and consists of PPARγ, cyclin D1, cyclin E, Bcl2-L1, p27 and CD95 (Apo-1/Fas ligand). The expression of P27, Bcl2, α-TTP, CYP3A, tropomyosin, Il-2, PPAR-γ, and CTGF appears to be up-regulated by one or more tocopherols whereas all other listed genes are down-regulated. Several mechanisms may underlie tocopherol-dependent gene regulation. In some cases protein kinase C has been implicated due to its deactivation by α-tocopherol and its participation in the regulation of a number of transcription factors (NFκB, AP-1). In other cases a direct involvement of PXR/ RXR has been documented. The antioxidant responsive element (ARE) appears in some cases to be involved as well as the transforming growth factor β responsive element (TGF-β-RE). This heterogeneity of mediators of tocopherol action suggests the need of a common element that could be a receptor or a co-receptor, able to interact with tocopherol and with transcription factors directed toward specific regions of promoter sequences of sensitive genes. Here we review recent results of the search for molecular mechanisms underpinning the central signaling mechanism.