bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunological detection and characterization of an estrus‐associated antigen in the goat oviduct
Authors: Abe Hiroyuki , Onodera Masakazu , Sugawara Shichiro 
Published: June 2005

AbstractThe present study was designed to investigate the possibility that the goat oviduct produces specific substance(s) similar to the oviductal glycoprotein (BOGP) of the bovine oviduct. Oviductal flushings obtained from goats at the follicular and luteal phases of the estrous cycle were examined by immunoblotting for the presence of material that cross‐reacted with monoclonal antibodies (MAbs) specific for BOGP. The MAbs immunoreacted with a broad band with a molecular mass of protein of about 97 kDa in the flushings of goat oviducts after fractionation of proteins by electrophoresis under reducing conditions. The antigen was present in flushings obtained from the ampullar segments of oviducts from goats at the follicular stage, but this antigen could hardly be detected in the flushings from the ampulla at the luteal phase and or the flushings from the isthmus at either the follicular or the luteal phase. This antigen was not detected in uterine flushings, follicular fluid, or serum. An immunohistochemical study demonstrated that the MAbs reacted specifically with the epithelial cells of the goat oviduct. Intense labeling was observed in the ampullar and fimbrial epithelia of goat oviducts at the follicular phase, but the immunohistochemical reaction was very weak at the luteal phase. In the isthmus, the reaction was faint during both the follicular and the luteal phase. No specific immunohistochemical reactivity with the MAbs was observed with other tissues from the reproductive tract or with nonre‐productive tissues. Immunofluorescent staining showed that the antigen was associated with the zona pellucida of goat ovarian eggs that had been incubated with ampullar flushings from goats at the follicular stage. These results indicate that the oviductal epithelial cells of the goat produce an oviduct‐specific antigen that is immunologically and biologically similar to BOGP. © 1995 Wiley‐Liss, Inc.
Effect of light and nutrient restriction on the metabolism of calcium and vitamin D in land snails
Authors: Kriajev Leonid , Edelstein Samuel 
Published: June 2005

AbstractBiomineralization in invertebrates, such as land snails, may serve as an excellent experimental model for understanding processes of skeletal calcification in higher organisms, the vertebrates. In the present study, the influence of nutrient and light restrictions on the calcification of the shell in land snails was investigated. It was found that nutrient and light restrictions led to an increase in weight and mineral content of shells. These events were accompanied by changes in the metabolism of vitamin D. The molluscan metabolite E was found to accelerate transfer of 45Ca from mantle to shell. On the basis of these findings it is suggested that in land snails adaptation to environmental changes such as light and nutritional restrictions is mediated by the vitamin D endocrine system. © 1995 Wiley‐Liss, Inc.
Modulation of prey‐capture behavior in Plethodon cinereus (Green) (Amphibia: Caudata)
Authors: Maglia Anne M. , Pyles Rebecca A. 
Published: June 2005

AbstractMany feeding kinematic studies do not identify sources of mechanical variation related to the type or size of prey. Studies of salamanders have concentrated on determining the morphological basis of feeding mechanics or on phylogenetic comparisons; few have examined variability within a species. A series of feeding trials was designed to test whether Plethodon cinereus of different age/size classes exhibits stereotypic patterns in capturing prey of differing type and size. Stopframe video analyses of feedings were made using 19 salamanders of varying body size and four prey types chosen to resemble items in the natural diet of the species. Five morphological features of each salamander, length and width of prey items, and 15 kinematic variables were used to describe each feeding trial.Statistical analyses of kinematic and morphological variables show that the feeding behavior of this species varies significantly with prey type. Effects of salamander size and prey size within prey types were a source of variation in some kinematic variables; among‐individual variation partitioned with salamander body size. Different feeding modes resulted from distinctive combinations of distances from prey, amount of tongue protrusion, body movements, and duration of mouth closure, which varied with the use of jaw prehension and lingual prey capture. Presence of a repertoire of behaviors, composed of versatile combinations of movements, suggests that Plethodon cinereus modulates feeding mechanics to capture different types of prey. Consideration of natural prey in experiments, and of prey type in comparisons made across taxa, are necessary to investigations of the evolution of feeding behaviors. © 1995 Wiley‐Liss, Inc.
Effects of annetocin, an oxytocin‐related peptide isolated from the earthworm Eisenia foetida, and some putative neurotransmitters on gut motility of the earthworm
Authors: Ukena K. , Oumi T. , Matsushima O. , Ikeda T. , Fujita T. , Minakata H. , Nomoto K. 
Published: June 2005

AbstractAnnetocin, an oxytocin‐related peptide recently isolated from the lumbricid earthworm Eisenia foetida, and putative transmitter substances were examined for their effects on rhythmic, spontaneous contractions of isolated gut preparations of the earthworm. Significant, dose‐dependent effects of the following substances were observed: acetylcholine (ACh), gamma‐aminobutyric acid (GABA), and dopamine were excitatory, while serotonin (5‐HT) and octopamine were inhibitory. Annetocin, oxytocin, and vasotocin stimulated spontaneous contraction of the earthworm gut, annetocin being approximately 10‐fold more potent than oxytocin or vasotocin. However, arginine‐vasopressin (Arg‐vasopressin), lysine‐vasopressin (Lys‐vasopressin), tocinoic acid (N‐terminal hexapeptide fragment of oxytocin), and MSH release‐inhibiting factor (MIF; C‐terminal tripeptide fragment of oxytocin) did not show any effect on the earthworm gut motility. On the other hand, oxytocin, vasotocin, Arg‐vasopressin, Lys‐vasopressin, and tocinoic acid caused spontaneous contractions of isolated rat uterine preparations, where the potency was in this order, while annetocin and MIF exerted no oxytocic activity on the uterus. Dose‐response relationship of the effects of annetocin and its related peptides on the annelid and mammalian systems shows that amino acid residue at the third position of these peptides is important for exertion of excitatory action on the smooth muscle systems. The results in the present study suggest that receptors for annetocin and for GABA on the earthworm gut, unlike those for ACh, desensitize during continuous exposure to these substances. © 1995 Wiley‐Liss, Inc.
Expression of osteopontin in the head process late in gastrulation in the rat
Authors: Thayer Jeanette M. , Giachelli Cecilia M. , Mirkes Philip E. , Schwartz Stephen M. 
Published: June 2005

AbstractOsteopontin (OPN) is a secreted, glycosylated phosphoprotein. Previous studies have implicated OPN in calcification/decalcification and inflammation. We became interested in developmental expression of OPN because of our previous findings that suggest OPN may play a role in formation of new vascular layers after injury, and because of our observation of developmental regulation in vascular smooth muscle cells. While OPN was expressed at low levels in vessels, only late in development, examination of very early expression patterns revealed a surprising finding. OPN was expressed exclusively in the head process, on day 9.0, late in gastrulation in the rat. In vitro studies of vascular smooth muscle cells have previously demonstrated that OPN promotes cell adhesion and migration. It is suggested that OPN may promote migration of cells, during gastrulation, via integrins which may be present in the head process or overlying ectoderm. © 1995 Wiley‐Liss, Inc.
Replicating DNA does not block germinal vesicle breakdown in mouse oocytes
Authors: Fulka J. , Moor R. M. , Fulka J. 
Published: June 2005

AbstractMouse germinal vesicle GV‐G2 stage oocytes were fused to very early S‐phase blastomeres from four cell stage embryos to test whether oocytes have a mechanism which detects replicating DNA and thereafter arrests meiosis at the GV stage. Our results show that oocytes are unable to recognize replicating DNA in transplanted nuclei and undergo germinal vesicle breakdown (GVBD), GVBD and blastomere nucleus breakdown are only blocked by inhibitors of both oocyte maturation and DNA synthesis. These results show that mouse immature oocytes do not possess a feedback control capable of detecting replicating DNA. © 1995 Wiley‐Liss, Inc.
Hamilton connectivity of line graphs and claw‐free graphs
Authors: Hu Zhiquan , Tian Feng , Wei Bing 
Published: June 2005

AbstractLet G be a graph and let V0 = {ν∈ V(G): dG(ν) = 6}. We show in this paper that: (i) if G is a 6‐connected line graph and if |V0| ≤ 29 or G[V0] contains at most 5 vertex disjoint K4's, then G is Hamilton‐connected; (ii) every 8‐connected claw‐free graph is Hamilton‐connected. Several related results known before are generalized. © 2005 Wiley Periodicals, Inc. J Graph Theory
A generalization of a Ramsey‐type theorem on hypermatchings
Authors: Baginski Paul 
Published: June 2005

AbstractFor an r‐uniform hypergraph G define N(G, l; 2) (N(G, l; ℤn)) as the smallest integer for which there exists an r‐uniform hypergraph H on N(G, l; 2) (N(G,l; ℤn)) vertices with clique(H) < l such that every 2‐coloring (ℤn‐coloring) of the edges of H implies a monochromatic (zero‐sum) copy of G. Our results strengthen a Ramsey‐type theorem of Bialostocki and Dierker on zero‐sum hypermatchings. As a consequence, we show that for any n ≥ 2, r ≥ 2, and l > r + 1, N(n𝒦, l;2) = N(n𝒦, l;ℤn) = (r + 1)n − 1. © 2005 Wiley Periodicals, Inc. J Graph Theory
Vibrational spectral studies of β‐alaninium perchlorate
Authors: Pandiarajan S. , Rajaram R. K. , Ramakrishnan V. 
Published: June 2005

AbstractFourier transform (FT) IR and FT‐Raman spectra were recorded at room temperature for crystals of β‐alaninium perchlorate. The observed wavenumbers in both spectra reveal that the amino acid has carbonyl and protonated amino groups that reflect the cationic form of the amino acid. The presence of a carboxyl cyclic dimer structure was revealed. The symmetry of the perchlorate ion is reduced from Td to C2v. Consequently, the degeneracies of a few modes are lifted and these were reflected in the spectra. Copyright © 2005 John Wiley & Sons, Ltd.
Anti‐Microbial Activity and Film Characterization of Thiazolidinone Derivatives of Chitosan
Authors: Kulkarni Anandrao R. , Kulkarni Venktrao H. , Keshavayya Jathi , Hukkeri Vijaykumar I. , Sung Hsing‐Wen 
Published: June 2005

AbstractCommunication: Thiazolidinone derivatives (TDCs) were prepared by converting chitosan into chitosan's Schiff's bases (CSBs), followed by treatment with mercaptoacetic acid. Both CSBs and TDCs were tested for antimicrobial activity against four different bacteria. All TDCs showed comparatively better anti‐microbial activity without much affecting basic physical properties of chitosan such as film‐forming capacity, tensile strength, etc. This indicates that chitosan derivatives with a thiazolidinone moiety might be a better material for wound dressing.
magnified image
Biosynthesis of an Elastin‐Mimetic Polypeptide with Two Different Chemical Functional Groups within the Repetitive Elastin Fragment
Authors: Junger Andreas , Kaufmann Doris , Scheibel Thomas , Weberskirch Ralf 
Published: June 2005

AbstractSummary: A new protein engineering strategy was utilized to synthesize an elastin‐mimetic polypeptide. The primary structure represents an elastic motif composed of thirty amino acids with one lysine and one glutamic acid per repeat unit EMM = (VPGVG VPGKG VGPVG VPGVG VPGEG VPGIG). The gene was constructed using a Seamless Cloning method by generating three DNA cassettes which all encoded the EMM repeat unit, but with different flanking restriction recognition sites. The DNA cassettes were assembled to yield a gene that could be directly cloned into the multiple cloning site of pBluescript® II SK+. The resulting gene (EMM)7 with approximately 650 base pairs in length was further cloned into the expression vector pET‐28b. Protein biosynthesis in E. coli strain BLR(DE3) resulted in the 21.5 kDa repeating polypeptide His6‐(EMM)7 yielding up to 50 mg · L−1 of cell culture. Secondary structure analysis by far UV circular dichroism revealed a minimum at 197 nm and a shoulder at 218 nm indicative for a random coil with some type II β‐turn conformation content. Lower critical solution temperature (LCST) behavior strongly depends on salt and polypeptide concentration. Importantly, first cross‐linking experiments indicate successful hydrogel formation with a surface structure reminiscent to natural elastin as visualized by SEM micrographs.
magnified image
Ionic Liquids as Reaction Medium in Cellulose Functionalization
Authors: Heinze Thomas , Schwikal Katrin , Barthel Susann 
Published: June 2005

AbstractSummary: The application of different ionic liquids (IL), namely 1‐N‐butyl‐3‐methylimidazolium chloride ([C4mim]+Cl−), 3‐methyl‐N‐butyl‐pyridinium chloride and benzyldimethyl(tetradecyl)ammonium chloride were investigated as solvents for cellulose. The ILs used have the ability to dissolve cellulose with a degree of polymerization in the range from 290 to 1 200 to a very high concentration. Using [C4mim]+Cl−, no degradation of the polymer appears. By 13C NMR measurement it was confirmed that this IL is a so‐called non‐derivatizing solvent. [C4mim]+Cl− can be applied as a reaction medium for the synthesis of carboxymethyl cellulose and cellulose acetate. Without using any catalyst, cellulose derivatives with high degree of substitution could be prepared.13C NMR spectrum of cellulose dissolved in the IL [C4mim]+Cl− (top). The 13C NMR spectrum of cellulose dissolved in DMSO/tetrabutylammonium fluoride trihydrate is shown for comparison (bottom).magnified image13C NMR spectrum of cellulose dissolved in the IL [C4mim]+Cl− (top). The 13C NMR spectrum of cellulose dissolved in DMSO/tetrabutylammonium fluoride trihydrate is shown for comparison (bottom).
SANS Study of Coated Block Copolymer Micelles
Authors: Pleštil Josef , Kříž Jaroslav , Koňák Čestmír , Pospíšil Herman , Kadlec Petr , Sedláková Zdeňka , Grillo Isabelle , Cubitt Robert 
Published: June 2005

AbstractSummary: Multishell particles were prepared by γ‐radiation‐induced polymerization of methyl methacrylate (MMA) in polystyrene‐block‐poly(methacrylic acid) (PS‐b‐PMA) aqueous micellar solution and their structure was studied by small‐angle neutron scattering (SANS). Before polymerization, almost all MMA molecules are distributed in aqueous phase and only 1% of MMA is accumulated inside the micelles. The newly formed polymer (PMMA) is deposited on the surface of PS cores of the original micelles. The effect of the MMA concentration, micelle concentration, absorbed radiation dose, and absorbed dose rate on the characteristics of the resulting particles was examined. The thickness of the PMMA shell (20–218 Å for the presented series of samples) can be easily controlled by variation of monomer and/or micelle concentration. Universal plots of the core volume (PS+PMMA) and SANS curve were presented. These plots facilitate choosing proper monomer and micelle concentrations and detecting possible irregularities in the parameters of the resulting particles.
magnified image
Novel High and Ultrahigh Molecular Weight Poly(propylene) Plastomers by Asymmetric Hafnocene Catalysts
Authors: Cobzaru Cecilia , Deisenhofer Sandra , Harley Andrew , Troll Carsten , Hild Sabine , Rieger Bernhard 
Published: June 2005

AbstractSummary: The novel asymmetric ansa‐complexes [1‐(9‐η5‐fluorenyl)‐2‐(2,5,7‐trimethyl‐indenyl)ethane]hafnium dichloride (7a) and [1‐(9‐η5‐fluorenyl)‐2‐(2,4,6‐trimethyl‐indenyl)ethane]hafnium dichloride (7b) were prepared and used as catalysts for propylene homopolymerization reactions after in situ activation. The synthetic route allows to separate the 4,6‐ and 5,7‐substituted ligand isomers before the complexation step. The orientation of the methyl groups to the “front” (4,6) or to the “back” (5,7) of the tetrahedral hafnocene dichloride species influences their performances in polymerization reactions. Whereas hafnocene (7b) which bears trimethyl substitution at 2,4,6‐positions of the indenyl moiety exhibits only moderate activity, the 2,5,7‐trimethyl substituted structure (7a) produces isotactic poly(propylene)s with high molecular weights (up to $\overline M _{\rm w}$ = 9.0 × 105 g · mol−1) and high activities [up to 3.2 × 105 kg of PP (mol Hf × h)−1]. A comparative analysis of polymerization data and mechanical behavior of 7a, and previously reported 6,7‐indenyl substituted complex 6b are reported.Typical stress‐strain curves of different types of poly(propylene)s.magnified imageTypical stress‐strain curves of different types of poly(propylene)s.
Metallocenic Copolymers of Isotactic Propylene and 1‐Octadecene: Crystalline Structure and Mechanical Behavior
Authors: Palza Humberto , López‐Majada Juan M. , Quijada Raúl , Benavente Rosario , Pérez Ernesto , Cerrada María L. 
Published: June 2005

AbstractSummary: A set of copolymers of isotactic propylene and 1‐octadecene (CiPOD) and the corresponding isotactic poly(propylene) homopolymer (iPP) have been synthesized using a metallocene catalyst. The influence of the incorporation of this long chain comonomer on the structure and final properties exhibited by iPP has been examined. Wide‐angle X ray diffraction and optical microscopy have been used to analyze the effect of introducing 1‐octadecene comonomer within the iPP backbone. The initial monoclinic crystal lattice with a well‐developed lamellar morphology is transformed into a mesomorphic modification showing very small entities. All these structural changes significantly influence the mechanical behavior of these copolymers. Thus, stiffness and microhardness are diminished and the brittle‐ductile transition can be observed by simply varying composition when deformation takes place at room temperature. On the other hand, the intensity of the process associated with cooperative movements within the amorphous phase (β relaxation) significantly goes up with the incorporation of 1‐octadecene and its location is shifted to lower temperature because of the decrease in the crystallinity content.X‐ray diffraction patterns at room temperature, with increasing comonomer content.magnified imageX‐ray diffraction patterns at room temperature, with increasing comonomer content.
Effect of [Pyridylmethanimine]/[CuI] Ratio, Ligand, Solvent and Temperature on the Activation Rate Constants in Atom Transfer Radical Polymerization
Authors: Tang Wei , Nanda Ajaya Kumar , Matyjaszewski Krzysztof 
Published: June 2005

AbstractSummary: The effect of [L]/[CuI] ratio, ligand, the choice of solvent and temperature on the activation rate constants in ATRP with catalyst complexes formed with two pyridylmethanimine ligands [PMI, i.e., N‐propyl‐pyridylmethanimine (NPPMI) and N‐octyl‐pyridylmethanimine (NOPMI)] were studied. Maximal values for the apparent rate constants were observed at an [L]/[CuI] ratio of ∼2/1 and 1/1 in polar and nonpolar solvents, respectively. This is similar to the results obtained with the CuI/bpy system and was attributed to the formation of [CuI/L2]+Br− and [CuI/L2]+CuIBr species. The CuI/NPPMI system was only soluble in polar reaction media; however, the CuI/NOPMI complex was soluble in both polar and less polar reaction media. The activation rate constants increased with increasing temperature and the value of activation energy (Ea) for CuI/NPPMI in the activation process was 58.1 kJ · M−1 · K−1.Arrhenius plot of ln ka versus 1/T for the activation process for NPPMI and bpy in acetonitrile; [CuIBr/NPPMI2]0 ([CuIBr/bpy2]0)/[EtBriB]0/[TEMPO]0/[TCB]0 = 20/1/10/2 × 10−3 M.magnified imageArrhenius plot of ln ka versus 1/T for the activation process for NPPMI and bpy in acetonitrile; [CuIBr/NPPMI2]0 ([CuIBr/bpy2]0)/[EtBriB]0/[TEMPO]0/[TCB]0 = 20/1/10/2 × 10−3 M.
Synthesis of Poly[(ethylene terephthalate)‐co‐(ε‐caprolactone)]‐Poly(propylene oxide) Block Copolyester by Direct Polyesterification of Reactive Oligomers
Authors: Saint‐Loup René , Robin Jean‐Jacques 
Published: June 2005

AbstractSummary: The objective of this study was to synthesize thermoplastic elastomers by the direct copolyesterification of reactive oligomers of poly[(ethylene terephthalate)‐co‐(ε‐caprolactone)] (PET) and poly(propylene oxide) (PPO). The synthesis of hard segment oligomers was achieved in two steps. The first step consisted of the glycolysis of PET leading to α,ω‐hydroxyl functionalized oligomers. The second step corresponded to the ring opening polymerization of ε‐caprolactone onto the hydroxyl end groups of the PET oligomers. Commercially available hydroxytelechelic poly(propylene oxide) was modified to obtain carboxytelechelic poly(propylene oxide). The chemical structure of the product was investigated by 1H NMR and size exclusion chromatography (SEC). Multiblock poly(ester‐ether) was then synthesized by polyesterification of hydroxytelechelic poly[(ethylene terephthalate)‐co‐(ε‐caprolactone)] with carboxytelechelic poly(propylene oxide) oligomers, using different catalysts and reaction conditions. The best stoichiometric ratio for the reaction was determined in order to obtain the highest possible $\overline M _{\rm n}$. The chemical structure of the synthesized poly(ester‐ether) was investigated by size exclusion chromatography and 1H NMR. The thermal and thermomechanical behavior of the synthesized poly(ester‐ether) was investigated by differential scanning calorimetry and dynamic mechanical analysis, which showed that the poly(ester‐ether) behaved as a thermoplastic elastomer. This product could also be an interesting way for chemical recycling of PET waste.Synthesis of multiblock co‐poly(ester‐ether).magnified imageSynthesis of multiblock co‐poly(ester‐ether).
Medium‐sized peptides as built in carriers for biologically active compounds
Authors: Hudecz Ferenc , Bánóczi Zoltán , Csík Gabriella 
Published: June 2005

AbstractA growing number of oligopeptides of natural and/or synthetic origin have been described and considered as targeting structures for delivery bioactive compounds into various cell types. This review will outline the discovery of peptide sequences and the corresponding mid‐sized oligopeptides with membrane translocating properties and also summarizede novodesigned structures possessing similar features. Conjugates and chimera constructs derived from these sequences with covalently attached bioactive peptide, epitope, oligonucleotide, PNA, drug, reporter molecule will be reviewed. A brief note will refer to the present understanding on the uptake mechanism at the end of each section. © 2005 Wiley Periodicals, Inc. Med Res Rev