bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of human serum albumin production in methylotrophic yeast Pichia pastoris by repeated fed‐batch fermentation
Authors: Ohya Tomoshi , Ohyama Masao , Kobayashi Kaoru 
Published: May 2005

AbstractAn optimization method for repeated fed‐batch fermentation was established with the aim of improving the recombinant human serum albumin (rHSA) production in Pichia pastoris. A simulation model for fed‐batch fermentation was formulated and the optimal methanol‐feeding policy calculated by dynamic programming method using five different methanol‐feeding periods. The necessary state variables were collected from the calculated results and used for further optimization of repeated fed‐batch fermentation. The optimal operation policy was investigated using the pre‐collected state variables by estimating the overall profit per total methanol‐feeding time. The calculated results indicated that the initial cell mass from the 2nd fed‐batch fermentation on should be set at 35 or 40 g and methanol‐feeding time at 264 h. In repeated fed‐batch fermentation using the optimal operation policy, actual culture volume was in good agreement with the values simulated by model equations, but some discrepancy was observed in rHSA production. Minimum experiments were therefore carried out to re‐evaluate rHSA production levels, which were then applied in re‐calculations to determine the optimal operation policy. The optimal policy for repeated fed‐batch fermentation established in the present study (i.e., 4‐times‐repeated fed‐batch fermentation) achieved a 47% increase in annual rHSA production. Optimization of the culture period also brought about a 28% increase in annual rHSA production even in simple (not repeated) fed‐batch fermentation. © 2005 Wiley Periodicals, Inc.
Abdominal obesity, insulin resistance, and colon carcinogenesis are increased in mutant mice lacking gastrin gene expression
Authors: Cowey Stephanie L. , Quast Michael , Belalcazar Ligia Maria , Wei Jingwa , Deng Xiaoling , Given Randall , Singh Pomila 
Published: May 2005

AbstractBACKGROUNDThe authors recently reported that gastrin gene knockout (GAS‐KO) mice had an increased risk for colon carcinogenesis in response to azoxymethane (AOM) compared with their wild type (WT) littermates. In the current report, the authors discuss the predisposition of GAS‐KO mice to develop obesity and metabolic hormonal changes that may contribute to their increased risk of colon carcinogenesis.METHODSThe weight and deposition of fat was monitored in the mice over a 14 month period, using magnetic resonance imaging and nuclear magnetic resonance techniques. Changes in plasma concentrations of ghrelin, leptin, insulin, and glucose were assessed using radioimmunoassay analysis and enzyme‐linked immunosorbent assays. Preneoplastic markers of colon carcinogenesis (aberrant crypt foci [ACFs]), in response to AOM, were measured in a subset of obese versus lean GAS‐KO mice and were compared with the markers in WT mice.RESULTSIncreases in visceral adiposity were evident by age 2 months in GAS‐KO mice, resulting in macroscopic obesity by age 7 months. Hyperinsulinemia and insulin:glucose ratios were increased significantly in GAS‐KO mice as young as 1 month and preceded alterations in nonfasting leptin and ghrelin levels. The number of ACFs per mouse colon were increased significantly in the following order: obese GAS‐KO mice > lean GAS‐KO mice > WT mice. Fasting plasma insulin levels were 0.88 ± 0.1 ng/mL, 1.45 ± 0.3, and 2.76 ± 0.9 ng/mL in the WT, GAS‐KO lean, and GAS‐KO obese mice, respectively.CONCLUSIONSThe current results suggest the novel possibility that loss of amidated gastrins may increase adipogenesis, hyperinsulinemia, and colon carcinogenesis in GAS‐KO mice. The increase in colon carcinogenesis may be due in part to hyperinsulinemia, increased obesity, and other associated hormone changes that were measured in GAS‐KO mice. Cancer 2005. © 2005 American Cancer Society.
Vanadium(V) Oxoperoxo Complexes with Side Chain SubstitutedN‐Salicylidenehydrazides: Modeling Supramolecular Interactions inVanadium Haloperoxidases
Authors: Nica Simona , Pohlmann Axel , Plass Winfried 
Published: May 2005

AbstractThe Schiff‐base ligand derived from salicylaldehyde and γ‐hydroxybutanoic acid hydrazide (H2Salhyhb) reacts with potassium metavanadate and hydrogen peroxide in a water/methanol solution with a pH value of around two to yield the corresponding vanadium(V) oxoperoxo complex [VO(O2)HSalhyhb(H2O)] (1). Complex 1 crystallizes with one molecule of water as 1·H2O in the monoclinic space group P21/n. For the vanadium atom a pentagonal‐bipyramidal coordination geometry is observed, with a side‐on bonded peroxo ligand in the equatorial plane. The hydroxy side chain of the hydrazide ligand is involved in a hydrogen‐bond network with the peroxo ligand at the vanadium atom. This network shows some similarities with the hydrogen‐bonding scheme found for the peroxo form of vanadium haloperoxidases. The stoichiometric reaction of 1 with 1,3,5‐trimethoxybenzene (TMB) in the presence of tetrabutylammonium bromide leads to the formation of 1‐bromo‐2,4,6‐trimethoxybenzene (Br‐TMB), thus mimicking the oxidative halogenation function of the native enzyme. Complex 1 is also capable of oxidizing triphenylphosphane and methylphenylsulfane, yielding a cis‐dioxovanadium(V) complex and the corresponding phosphane or sulfane oxide, respectively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Endoplasmic reticulum stress induces the phosphorylation of small heat shock protein, Hsp27
Authors: Ito Hidenori , Iwamoto Ikuko , Inaguma Yutaka , Takizawa Takenori , Nagata Koh‐ichi , Asano Tomiko , Kato Kanefusa 
Published: May 2005

AbstractThere are several reports describing participation of small heat shock proteins (sHsps) in cellular protein quality control. In this study, we estimated the endoplasmic reticulum (ER) stress‐induced response of Hsp27 and αB‐crystallin in mammalian cells. Treatment targeting the ER with tunicamycin or thapsigargin induced the phosphorylation of Hsp27 but not of αB‐crystallin in U373 MG cells, increase being observed after 2–10 h and decline at 24 h. Similar phosphorylation of Hsp27 by ER stress was also observed with U251 MG and HeLa but not in COS cells and could be blocked using SB203580, an inhibitor of p38 MAP kinase. Other protein kinase inhibitors, like Gö6983, PD98059, and SP600125, inhibitors of protein kinase C (PKC), p44/42 MAP kinase, and JNK, respectively, were without major influence. Prolonged treatment with tunicamycin but not thapsigargin for 48 h caused the second induction of the phosphorylation of Hsp27 in U251 MG cells. Under these conditions, the intense perinuclear staining of Hsp27, with some features of aggresomes, was observed in 10%–20% of the cells. © 2005 Wiley‐Liss, Inc.
A Versatile Preparation Route for Thin Free‐Standing Liquid Single Crystal Elastomers
Authors: Komp Ansgar , Rühe Jürgen , Finkelmann Heino 
Published: May 2005

AbstractSummary: Thin films of nematic and cholesteric side‐chain polymers containing reactive benzophenone units can be macroscopically oriented by electric/magnetic fields or surface interactions. After UV‐irradiation, liquid single crystal elastomers (LSCEs) are formed. With this simple, new pathway, macroscopically ordered free‐standing LSCE films are easily accessible having a thickness in the range of about 100 nm to 100 μm as outlined in Figure.
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Laser Single Pulse Initiated RAFT Polymerization for Assessing Chain‐Length Dependent Radical Termination Kinetics
Authors: Buback Michael , Junkers Tanja , Vana Philipp 
Published: May 2005

AbstractSummary: A novel method combining RAFT polymerization with pulsed‐laser initiation for determining chain‐length dependent termination rate coefficients, kt, is presented. Degenerative chain‐transfer in RAFT enables single‐pulse pulsed‐laser polymerization (SP‐PLP) traces to be measured on systems with a narrow radical distribution that remains essentially unchanged during the experiment. SP‐PLP‐RAFT experiments at different polymerization times allow for determining kt as a function of chain length via classical kinetics assuming chain‐length independent kt.Single‐pulse pulsed‐laser polymerization trace for BMPT‐mediated RAFT polymerization of butyl acrylate.magnified imageSingle‐pulse pulsed‐laser polymerization trace for BMPT‐mediated RAFT polymerization of butyl acrylate.
New Poly(propylene glycol)‐ and Poly(ethylene glycol)‐Based Polymer Gelators with L‐Lysine
Authors: Suzuki Masahiro , Owa Sanae , Shirai Hirofusa , Hanabusa Kenji 
Published: May 2005

AbstractSummary: New polymer gelators consisting of poly(propylene glycol) or poly(ethylene glycol) and L‐lysine‐based low‐molecular‐weight gelators have been developed. These polymer gelators were synthesized according to a simple procedure with high reaction yield, and formed organogels in many organic solvents. The organogelation mechanism was proposed from the transmission electron microscopy and FTIR spectroscopy studies.Structures of the polymer gelators synthesized here.magnified imageStructures of the polymer gelators synthesized here.
Thermal conductivity of high strength polyethylene fiber in low temperature
Authors: Yamanaka Atsuhiko , Fujishiro Hiroyuki , Kashima Toshihiro , Kitagawa Tooru , Ema Kimiko , Izumi Yoshinobu , Ikebe Manabu , Nishijima Shigehiro 
Published: May 2005

AbstractHigh strength polyethylene fiber (Toyobo, Dyneema® fiber, hereinafter abbreviated to DF) used as reinforcement of fiber‐reinforced plastics for cryogenic use has a high thermal conductivity. To understand the thermal conductivity of DF, the relation between fiber structure and thermal conductivity of several kinds of polyethylene fibers having different modulus from 15 to 134 GPa (hereinafter abbreviated to DFs) was investigated. The mechanical series‐parallel model composed of crystal and amorphous was applied to DFs for thermal conductivity. This mechanical model was obtained by crystallinity and crystal orientation angle measured by solid state NMR and X‐ray. Thermal conductivity of DF in fiber direction was dominated by that of the continuous crystal region. The thermal conductivity of the continuous crystal part estimated by the mechanical model increases from 16 to 900 mw/cmK by the increasing temperature from 10 to 150K, and thermal diffusivity of the continuous crystal part was estimated to about 100 mm2/s, which is almost temperature independent. The phonon mean free path of the continuous crystal region of DF obtained by thermal diffusivity is almost temperature independent and its value about 200 Å. With the aforementioned, the mechanical series‐parallel model composed of crystal and amorphous regions could be applied to DFs for thermal conductivity. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1495–1503, 2005
Proton conducting composite membranes from polysulfone and heteropolyacid for fuel cell applications
Authors: Smitha B. , Sridhar S. , Khan A. A. 
Published: May 2005

AbstractThe viability of using composite membranes of heteropolyacid (HPA)/polysulfone (PSF), HPA/sulfonated polysulfone (SPSF) for use in proton exchange membrane fuel cells (PEMFC) was investigated. PSF and its sulfonated polymer, SPSF was solution‐blended with phosphotungstic acid, a commercially available HPA. Fourier transform infrared (FTIR) spectroscopy of the HPA–40/SPSF composite exhibited band shifts showing a possibility of intermolecular hydrogen bonding interaction between the HPA additive and the sulfonated polymer. The composite membranes exhibited improved mechanical strength and low water uptake. The conductivity of the composite membrane, HPA–40/SPSF, consisting of 40 wt % HPA and 60 wt % SPSF [with a degree of Sulfonation (DS) of 40%] exhibited a conductivity 0.089 S/cm at room temperature that linearly increased upto 0.14 S/cm at 120 °C, whereas the widely used commercial membrane Nafion 117, exhibited a room temperature conductivity of 0.1 S/cm that increased to only 0.12 S/cm at 120 °C. In contrast, the composite of HPA–40/PSF exhibited a proton conductivity of 0.02 S/cm at room temperature that increased only to 0.07 S/cm at a temperature of 100 °C. The incorporation of HPA into SPSF not only rendered the membranes suitable for elevated temperature operation of PEMFC but also provides an inexpensive alternative compared to Nafion. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1538–1547, 2005
Surface Analysis of Plasma‐Deposited Polymer Films, 4
Authors: Swaraj Sufal , Oran Umut , Lippitz Andreas , Schulze Rolf‐Dieter , Friedrich Joerg F. , Unger Wolfgang E. S. 
Published: May 2005

AbstractSummary: XPS and NEXAFS spectroscopy were used for the chemical characterization of pulsed plasma‐deposited ethylene films before and after exposure to ambient air. The influence of external plasma parameters on the spectroscopic results was investigated. Information on the chemical character of the plasma‐polymerized films, such as the regularity of the primary structure, the amount of long‐living radicals, and branching or cross‐linking or both was derived from this data. “Irregularity” and radical concentration for post‐plasma reactions of the plasma‐deposited films increased with the duty cycle or power. A decreased level of monomer fragmentation and, consequently, an increase in regularity is partially concluded from the experimental data when the monomer pressure is increased. The concentration of surface radicals available for post‐plasma reactions also increased with monomer pressure. The correlation found between the degree of the post‐plasma oxygen incorporation and the variation of the various external parameters agreed with earlier ToF‐SSIMS findings.
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Controlled Surface Engineering and Device Fabrication of Optoelectronic Polymers and Carbon Nanotubes by Plasma Processes
Authors: Chen Wei , Dai Liming , Jiang Hao , Bunning Timothy J. 
Published: May 2005

AbstractSummary:Owing to theirπ‐electron delocalization along the backbone, conjugated polymers possess unique optoelectonic properties attractive for a wide range of applications in various electronic and photonic devices. Having a conjugated all‐carbon structure with specific molecular symmetries, carbon nanotubes have also attracted a great deal of interest for optoelectronic applications. It is well known that surface and/or interfacial properties are of paramount importance for most optoelectronic applications. Recent developments in the field have clearly indicated the possibility of using radio‐frequency glow‐discharge plasma for introducing functional surfaces/interfaces with region‐specific characteristics necessary for advanced electronic and/or photonic devices. In this article, we summarize our work on the use of plasma processes (both plasma treatment and plasma polymerization) for the surface and interface control of optoelectronic polymers and carbon nanotubes for potential applications in electronic and photonic devices, and reference is also made to other complementary work as appropriate.A low magnification SEM micrograph of multicomponent, interposed, carbon nanotube micropatterns with non‐aligned carbon nanotubes region‐specifically adsorbed between aligned carbon nanotube patterns.magnified imageA low magnification SEM micrograph of multicomponent, interposed, carbon nanotube micropatterns with non‐aligned carbon nanotubes region‐specifically adsorbed between aligned carbon nanotube patterns.
Photoluminescence studies of Eu‐implanted GaN epilayers
Authors: Katchkanov V. , O'Donnell K. P. , Dalmasso S. , Martin R. W. , Braud A. , Nakanishi Y. , Wakahara A. , Yoshida A. 
Published: May 2005

AbstractPhotoluminescence (PL) of Eu‐implanted GaN epilayers grown by Metalorganic Vapour Phase Epitaxy (MOVPE) was studied as a function of temperature. The implantation was done at ion energies of 75 keV, 200 keV and 350 keV with doses of 1014cm–2and 1015cm–2. PL spectra of all samples show the emission line assigned to the5D0–7F2transition of Eu3+in GaN to be split into three spectral components at 620.7 nm, 621.6 nm and 622.5 nm. The split lines are seen to have very different temperature dependences of integrated intensity. Such splitting might be explained by Eu3+ion site multiplicity. The variation of the temperature quenching factor of the PL integrated intensity from sample to sample and from line to line suggests that optically active Eu3+ions are coupled to defects and impurities, thus forming complexes with different energy position of the carrier trapping level in the bandgap of GaN. The appearance and quenching of an additional PL line at 617.3 nm with increasing temperature is observed in the range of 13–295 K. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structure, stability and electronic properties of TiO2 nanostructures
Authors: Enyashin Andrey N. , Seifert Gotthard 
Published: May 2005

AbstractThe structural properties, the stability and the electronic properties of various nanostructures based on the titania layer modifications (anatase and lepidocrocite) are studied using the density‐functional‐based tight‐binding method (DFTB). The anatase nanotubes were found as the most stable nanostructure of TiO2. Based on the results of the calculations of the anatase nanostructures a model of their stability was developed. All anatase nanoforms are semiconductors with a direct band gap (∼4.2 eV). The lepidocrocite nanotubes are semiconductors with an indirect band gap (∼4.5 eV). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The European Forum for Clinical Management: prophylaxis against the respiratory syncytial virus in infants and young children with congenital cardiac disease
Authors: Tulloh Robert M. R. , Feltes Timothy F. 
Published: May 2005

A recent, randomised, double-blind, placebo-controlled trial has demonstrated the effectiveness of palivizumab (Synagis®) for prophylaxis against infection by the respiratory syncytial virus in 1,287 young children with congenital cardiac disease. Guidelines for the use of palivizumab in these children considered to be at high risk were published by the American Academy of Pediatrics, followed by similar guidelines from the British Paediatric Cardiac Association, and recommendations from a number of other individual countries, including Canada, Germany, Spain, and France.In May, 2004, further discussion was held between a group of 15 paediatric cardiologists at a European forum for clinical management held in Munich, Germany. The objective of this forum was to define optimal recommendations on prevention of infection by the respiratory syncytial virus in infants and young children with congenital cardiac disease, appropriate to the clinical needs and style of those practising in paediatrics in individual countries. Participants were invited because of their knowledge of the therapeutic area, and for their experience of using palivizumab for prophylaxis against the respiratory syncytial virus in children with congenitally malformed hearts. Measures to educate the carers of children with such congenital malformations on precautions against infection by the respiratory syncytial virus were discussed, along with the many different aspects of best practice for therapeutic prophylaxis with palivizumab. The most appropriate timing of prophylaxis, recommendations for which children are most likely to benefit from prophylaxis, and suggested protocols were among the issues covered. The recommendations resulting from the discussions are presented in this paper, as a step towards reaching consensus.
Regulation of Peroxisome Proliferator Activated Receptor‐γ in Rat Pituitary
Authors: Nogueiras R. , Caminos J. E. , Gallego R. , Raghay K. , Bravo S. , Tovar S. , Pombo C. , López M. , Tena‐Sempere M. , García‐Caballero T. , Diéguez C. 
Published: May 2005

AbstractPeroxisome proliferator activated‐receptor γ (PPARγ) is a member of the nuclear receptor superfamily and, in addition to its relation with obesity and insulin sensitivity, it has recently been localized in human and mice pituitary, indicating a functional significance of PPARγ in adenopituitary tumours. In the present study, we localized the PPARγ mRNA and protein in different cell types of rat pituitary. Moreover, using the real‐time polymerase chain reaction, we assessed the mRNA expression of PPARγ in different physiological and pathological settings known to be associated with alterations in anterior pituitary cell proliferation and/or function. Our experiments have shown that PPARγ mRNA levels were repressed by oestrogen through an oestrogen receptor‐α effect. However, PPARγ protein levels were only modified in males but not in females. On the other hand, PPARγ mRNA expression was increased in dwarf rats in comparison with Lewis rats. Finally, nutritional, thyroid status or pregnancy did not change PPARγ expression. Taken together, we provide new data regarding the regulation of pituitary PPARγ mRNA by hormonal and metabolic status.
Effect of Prolyl Endopeptidase Inhibition on Arginine‐Vasopressin and Thyrotrophin‐Releasing Hormone Catabolism in the Rat Brain
Authors: Bellemère G. , Vaudry H. , Morain P. , Jégou S. 
Published: May 2005

AbstractCompound S 17092 is a potent and selective inhibitor of prolyl endopeptidase (EC 3.4.21.26, PEP) that may be of therapeutic value for the treatment of memory impairment associated with neurodegenerative diseases. In the present study, we investigated the effects of S 17092 on the catabolism of the promnesic neuropeptides thyrotrophin‐releasing hormone (TRH) and arginine‐vasopressin (AVP) in the rat brain. In vitro, bacterial PEP hydrolysed both TRH and AVP, and the breakdown of the two peptides was almost completely prevented by 10−5 M S 17092. In vivo, a single oral administration of S 17092 provoked a significant increase in TRH‐like immunoreactivity (TRH‐LI) in the cerebral cortex (+63% for a 10 mg/kg dose and +72% for a 30 mg/kg dose), as well as AVP‐LI in the hippocampus (+54% for a 30 mg/kg dose), but did not affect TRH‐LI in the amygdala nor AVP‐LI in the cerebral cortex. Chronic administration of S 17092 (10 or 30 mg/kg daily) lead to a significant increase in THR‐LI in the cerebral cortex (+55% and +56%, respectively), but did not modify AVP‐LI in the hippocampus, nor in the cerebral cortex. These results show that the selective PEP inhibitor S 17092 increases TRH and AVP content in discrete regions of the rat brain. The present data suggest that the promnesic and antiamnesic effects of S 17092 can be accounted for, at least in part, by blockage of AVP and TRH degradation by PEP.