bluuebunny/crossref_metadata_2025_split huggingface dataset:
Processing Factors Affecting the Yield and Physicochemical Properties of Starch from Cassava Chips and Flour
Authors: Olomo Victor , Ajibola Obafemi 
Published: October 2003

AbstractThree processing factors, namely, raw materials type (RMT) (i.e. chips and flour) and raw material drying mode (RDM) (i.e. sun‐ and oven‐drying at 55 °C) were related to the yield and some physicochemical properties of starch in a 23 factorial experiment. The quality characteristics investigated were: moisture content, pH, crude fiber content, peak viscosity and pasting temperature. Starch yields from oven‐dried chips and flour were significantly higher (at 5%) than from sun‐dried materials. The optimal yield of 55.9 g (per 70 g of dried product or 79.9%) was obtained from oven‐dried starch extracted from oven‐dried flour. The peak viscosities (PV) of starches extracted from flour and chips were similar while the observed pasting temperatures of flour‐extracted starches were not significantly different from those derived from chips.
Physical Basis for Separation of Rice Starch using Various Density Gradient Systems and its Effect on Starch Recovery, Purity, and Pasting Properties
Authors: Guraya Harmeet S. , James Charles , Champagne Elaine T. 
Published: October 2003

AbstractA 32% waxy and non waxy rice flour slurry containing starch‐protein agglomerates was physically disrupted in presence of water by use of high pressure homogenizer called Microfluidizer®. Microfluidized rice flour slurry from passes 2 and 4 was collected followed by isolation of starch using three different density gradient solutions/systems (CeCl, NaCl/sucrose and ZnSO4·7H2 O). Complete deagglomeration was obtained after passing the rice flour slurry four times through the Microfluidizer®. The recovery of isolated starch varied from 76.28% to 91.20% for different density gradient systems. The degree of deagglomeration did not seem to affect recovery but affected the purity of the isolated starches. All starches produced from pass 4 rice slurry resulted in starches with residual protein below 0.5%. Higher density of the gradient solution resulted in higher recovery and purity of starch. The isolation method had a significant effect on the pasting properties of the isolated starch. Residual protein in isolated starch had a negative correlation with peak viscosity and setback of pass 2 waxy and nonwaxy starches. The salts were retained in purified starch despite rigorous washing (at least 75 times greater than the control) and could affect starch properties.
Improved Calcium Sequestering Carbohydrate Based Agents
Authors: Besemer Arie C. , Jetten Jan M. , Slaghek Ted M. 
Published: October 2003

AbstractThe improved tandem oxidation sequence of starch with the aim of developing, e.g. degradable co‐builders suitable for laundry formulations as an alternative to the currently used polyacrylates is described. The tandem oxidation of starch starts with sodium periodate treatment of granular starch followed by oxidation of the dialdehyde product with sodium chlorite to dicarboxy starch. It turns out that improving the periodate oxidation resulting in a more complete transformation of the glucose moiety into the dialdehyde product yields, after sodium chlorite oxidation, a dicarboxy starch with a calcium sequestering capacity of 3.3 mmol Ca2+ per gram of dicarboxy product. This is an improvement of about 25% compared with current literature data.
Characterization and Utilization of Acid‐modified Rice Starches for Use in Pharmaceutical Tablet Compression
Authors: Puchongkavarin Hatairat , Bergthaller Wolfgang , Shobsngob Sujin , Varavinit Saiyavit 
Published: October 2003

AbstractAcid modified, agglomerated starches offer specific advantages as fillers in production of pharmaceutical tablets. Spray drying can improve processing of tablet mixtures significantly. In order to investigate prerequisites in utilization of rice starch, non‐waxy and waxy types were partially hydrolyzed in 6% (w/v) HCl solution at room temperature for varied length of time to obtain rice starches with increased crystallinity (so‐called crystalline rice starches). Scanning electron micrographs of native and highly crystalline starches were used to study the morphological changes and to suggest the mode of acid attack during hydrolysis. Exo‐corrosion distributed over the surface of acid‐modified waxy rice starch (AWRS) was observed after 192 h of hydrolysis. In contrast, the surface of acid‐modified rice starch (ARS) remained unchanged at 192 h of acid hydrolysis. The amylose content and the median particle size (diameter) were reduced with increasing hydrolysis time. It was found by X‐ray diffraction that the relative crystallinity of acid‐modified starches at >95% relative humidity was clearly increased with prolonged hydrolysis time.For studying tablet properties spherical agglomerates of the native and acid modified starches were directly compressed at 4 kN to obtain tablets. Crushing strength and disintegration time of tablets increased with relative crystallinity. In contrast, tablet friability was reduced. Concerning tablet functionality, the crystalline starches were positioned in overlapping ranges between the common commercial tablet fillers (microcrystalline cellulose, pregelatinized starch and lactose, respectively).
Evidence that the metabotropic glutamate receptor 5 antagonist MPEP may act as an inhibitor of the norepinephrine transporter in vitro and in vivo
Authors: Heidbreder Christian A. , Bianchi Massimiliano , Lacroix Laurent P. , Faedo Stefania , Perdona Elisabetta , Remelli Rosaria , Cavanni Paolo , Crespi Francesco 
Published: October 2003

AbstractThe mechanisms through which blockade of metabotropic glutamate receptors 5 (mGluR5) results in anxiolytic and antidepressant effects are currently unknown. In the present study, we therefore hypothesized that the anxiolytic‐ and antidepressant‐like profile of the noncompetitive mGluR5 receptor antagonist 2‐ethyl‐6‐(phenylethynyl)‐pyridine (MPEP) may be mediated by inhibition of the norepinephrine transporter (NET). Accordingly, we first examined the potency of MPEP to bind to or inhibit uptake at the NET as well as the dopamine and serotonin transporters (DAT and SERT, respectively). We also examined the simultaneous in vivo effects of MPEP and desipramine (DMI) on both NE‐like oxidation current in the amygdala (AMY) and cell firing in the locus coeruleus (LC) by means of differential pulse voltammetry (DPV) coupled with electrophysiology. MPEP completely displaced the binding of [3H]‐nisoxetine on human NET with a pKi of 6.63 ± 0.02. In addition, MPEP was able to inhibit [3H]‐NE uptake in LLCPK cells expressing human NET, with a pIC50 of 5.55 ± 0.09. In vivo DPV data revealed that both MPEP (30 mg/kg i.p.) and DMI (10 mg/kg i.p.) significantly increased NE‐like voltammetric responses levels in the AMY, whereas both compounds also significantly decreased cell firing monitored concomitantly from the second microelectrode in the LC. Collectively, the results of the present study provide potential new mechanisms through which MPEP exerts its anxiolytic and antidepressant effects. Synapse 50:269–276, 2003. © 2003 Wiley‐Liss, Inc.
Early embryonic death of glutamate carboxypeptidase II (NAALADase) homozygous mutants
Authors: Tsai G. , Dunham K.S. , Drager U. , Grier A. , Anderson C. , Collura J. , Coyle J.T. 
Published: October 2003

AbstractGlutamate carboxypeptidase II (EC 3.4.17.21) catalyzes the hydrolysis (Km = 0.2 μM) of the neuropeptide N‐acetylaspartylglutamate to yield N‐acetylaspartate and glutamate and also serves as a high‐affinity folate hydrolase in the gut, cleaving the polyglutamate chain to permit the absorption of folate. N‐acetylaspartylglutamate is an agonist at the mGluR3 metabotropic receptor and a source of extracellular glutamate through hydrolysis by glutamate carboxypeptidase II. Given the important role of glutamate in brain development and function, we were interested in the effects of a null mutation of glutamate carboxypeptidase II that would potentiate the effects of N‐acetylaspartylglutamate. The PGK‐Neomycin cassette was inserted to delete exons 9 and 10, which we previously demonstrated encode for the zinc ligand domain essential for enzyme activity. Successful germline transmission was obtained from chimeras derived from embryonic stem cells with the targeted mutation of glutamate carboxypeptidase II. Homozygous null mutants did not survive beyond embryonic day 8. Folate supplementation of the heterozygous mothers did not rescue the homozygous embryos. Mice heterozygous for the null mutation appeared grossly normal and expressed both mutated and wild‐type mRNA but the activity of glutamate carboxypeptidase II is comparable to the wild‐type mice. The results indicate that the expression of glutamate carboxypeptidase II is upregulated when one allele is inactivated and that its activity is essential for early embryogenesis. Synapse 50:285–292, 2003. © 2003 Wiley‐Liss, Inc.
Stimulation of postsynaptic α1b‐ and α2‐adrenergic receptors amplifies dopamine‐mediated locomotor activity in both rats and mice
Authors: Villégier Anne‐Sophie , Drouin Candice , Bizot Jean‐Charles , Marien Marc , Glowinski Jacques , Colpaërt Francis , Tassin Jean‐Pol 
Published: October 2003

AbstractRecent experiments have shown that mice lacking the α1b‐adrenergic receptor (α1b‐AR KO) are less responsive to the locomotor hyperactivity induced by psychostimulants, such as D‐amphetamine or cocaine, than their wild‐type littermates (WT). These findings suggested that psychostimulants induce locomotor hyperactivity not only because they increase dopamine (DA) transmission, but also because they release norepinephrine (NE). To test whether NE release could increase DA‐mediated locomotor hyperactivity, rats were treated with GBR 12783 (10 mg/kg), a specific inhibitor of the DA transporter, and NE release was enhanced with dexefaroxan (0.63–10 mg/kg), a potent and specific antagonist at α2‐adrenergic receptors. Dexefaroxan increased the GBR 12783‐mediated locomotor response by almost 8‐fold. The role of α1b‐ARs in this effect was then verified in α1b‐AR KO mice: whereas dexefaroxan (1 mg/kg) doubled locomotor hyperactivity induced by GBR 12783 (14 mg/kg) in WT mice, it decreased it by 43% in α1b‐AR KO mice. Finally, to test whether this latter inhibition was related to the occupation of α2‐adrenergic autoreceptors or of α2‐ARs not located on noradrenergic neurons, effects of dexefaroxan on locomotor hyperactivity induced by D‐amphetamine (0.75 mg/kg) were monitored in rats depleted in ascending noradrenergic neurons. In these animals dexefaroxan inhibited by 25–70% D‐amphetamine‐induced locomotor hyperactivity. These data indicate not only that the stimulation of α1b‐ARs increases DA‐mediated locomotor response, but also suggest a significant implication of postsynaptic α2‐ARs. Involvement of these adrenergic receptor mechanisms may be exploited in the therapy of Parkinson's disease. Synapse 50:277–284, 2003. © 2003 Wiley‐Liss, Inc.
Synaptic plasticity in rat subthalamic nucleus induced by high‐frequency stimulation
Authors: Shen Ke‐Zhong , Zhu Zi‐Tao , Munhall Adam , Johnson Steven W. 
Published: October 2003

AbstractThe technique of deep brain stimulation (DBS) has become a preferred surgical choice for the treatment of advanced Parkinson's disease. The subthalamic nucleus (STN) is presently the most promising target for such DBS. In this study, whole‐cell patch‐clamp recordings were made from 46 STN neurons in rat brain slices to examine the effect of high‐frequency stimulation (HFS) of the STN on glutamatergic synaptic transmission in STN neurons. HFS, consisting of trains of stimuli at a frequency of 100 Hz for 1 min, produced three types of synaptic plasticity in 17 STN neurons. First, HFS of the STN induced short‐term potentiation (STP) of evoked postsynaptic current (EPSC) amplitude in four neurons. STP was associated with a reduction in the EPSC paired‐pulse ratio, suggesting a presynaptic site of action. Second, HFS of the STN generated long‐term potentiation (LTP) of EPSC amplitude in eight neurons. Although the EPSC paired‐pulse ratio was reduced transiently in the first 2 min following HFS, ratios measured 6–20 min after HFS were unchanged from control. This suggests that LTP is maintained by a postsynaptic mechanism. Third, HFS produced long‐term depression (LTD) of EPSC amplitude in five STN neurons. LTD was associated with a significant increase in EPSC paired‐pulse ratios, indicating a presynaptic site of action. These results suggest that HFS can produce long‐term changes in the efficacy of synaptic transmission in the STN. HFS‐induced synaptic plasticity might be one mechanism underlying the effectiveness of DBS in the STN as a treatment of advanced Parkinson's disease. Synapse 50:314–319, 2003. © 2003 Wiley‐Liss, Inc.
Activation of metabotropic glutamate receptor 5 is associated with effect of amphetamine on brain neurons
Authors: Yu Meng‐Fen , Lin Wan‐Wan , Li Li‐Tzu , Yin Hsiang‐Shu 
Published: October 2003

AbstractThe role of metabotropic glutamate receptor 5 (mGluR5) was explored in mechanisms underlying the action of amphetamine (AMPH). The activity of mGluR5 was monitored by measuring the level of [3H]inositol monophosphates in brain neurons, in response to stimulation of 2‐choloro‐5‐hydroxyphenylglycine (CHPG), a selective agonist of mGluR5. Treatment with 1 μM of AMPH for 1 h or 7 days increased the CHPG (1 mM, 30 min)‐evoked phosphoinositide turnover by 46% or 92% and 26% or 84% in cultured cortical and hippocampal neurons, respectively, from that of CHPG‐only treated cells. When AMPH was present during CHPG application post‐1 h or 7 day AMPH incubation, the rate of phosphoinositide hydrolysis in cortical neurons became 121% or 142% higher than that treated with CHPG only. The postnatal day (P) 21 (juvenile) and P60 (adult) rats received three intraperitoneal injections of 5 mg/kg of AMPH or saline daily for 6 days. They were challenged on the eighth day with one dosage and sacrificed 3 h later. Reversible 3H‐glutamate binding detected increases of 22–89% in the binding levels of cortex and hippocampus of both ages following the AMPH injections. Increases of 13–18% in the levels of mGluR5 mRNA were seen in the juvenile pyramidal neurons of hippocampal CA1‐4, granular cells of dentate gyrus, and ventral thalamic nuclei, as shown by in situ hybridization. The AMPH‐induced altered activity of mGluR5 is probably associated with changes in the expression of the glutamate receptors, including mGluR5. AMPH may modify the sensitivity of mGluR5 or interact with the receptor itself. Synapse 50:334–344, 2003. © 2003 Wiley‐Liss, Inc.
Characterization of fluoxetine plus olanzapine treatment in rats: A behavior, endocrine, and immediate‐early gene expression analysis
Authors: Horowitz Judith M. , Goyal Alpna , Ramdeen Navindra , Hallas Brian H. , Horowitz A. Thomas , Torres German 
Published: October 2003

AbstractA large number of individuals afflicted with psychiatric disorders, particularly depression with psychotic features, do not respond to conventional drug therapy. An option for this phenomenon is to augment a standard selective serotonin (5‐HT) reuptake inhibitor with an atypical antipsychotic agent. In this regard, fluoxetine and olanzapine have been used concomitantly for treatment‐resistant depression and bipolar depression. Although highly efficacious in terms of producing superior improvement of symptoms across a variety of psychological measures, the motor patterns, endocrine profiles, and intracellular signaling pathways affected by drug augmentation have not been determined. Here we show that fluoxetine (10 mg/kg) plus olanzapine (5 mg/kg) given to rats for 7 consecutive days (i.e., subchronic treatment) alters motor activity and diminishes spontaneous behaviors as measured by spatial position and angular path analyses. In addition, the same drug combination pattern sensitizes peak adrenal corticosterone secretion without altering serum glucose levels. We also show that subchronic fluoxetine and olanzapine exposure suppresses the induction of two immediate‐early gene transcription factors (e.g., pCREB and FOS) that are associated with long‐lasting changes in synaptic efficacy and structural modifications in the prefrontal cortex, piriform cortex, and hippocampus. These results suggest that fluoxetine plus olanzapine can interact in a fashion not predicted by the currently accepted model of fluoxetine monotherapy and provide insight into the synergistic actions of drug augmentation in patients with treatment‐resistant depression. Synapse 50:353–364, 2003. © 2003 Wiley‐Liss, Inc.
One‐step measurement of firefly luciferase activity in yeast
Authors: Leskinen P. , Virta M. , Karp M. 
Published: October 2003

AbstractFirefly luciferase is often used as a sensitive genetic reporter in various cell types. The pitfall in yeast, however, has been the need to break down the rigid cells in order to measure the enzyme activity. In this study we have removed the peroxisomal targeting codons from the Photinus pyralis luciferase gene (luc) and shown that in the yeast Saccharomyces cerevisiae this modified luciferase gives high levels of light emission that is easy to measure from intact living cells. Furthermore, cells with the modified luciferase grew essentially faster than those with the wild‐type luciferase, indicating that peroxisomal targeting of a foreign enzyme puts some constraints to cellular viability. As a model system we used two different reporter constructs. In the first, expression of the luciferase gene is under control of CUP1‐promoter, a well known yeast promoter that is inducible by copper ions. In the second, luciferase activity is dependent on activation of the human oestrogen receptor and its interaction with oestrogen‐responsive elements incorporated in a yeast promoter. The luciferase activity measurement could be done on a 96‐well plate by simple addition of the substrate, D‐luciferin, at a moderately acidic pH of 5.0. The ease of use of the non‐peroxisomal luciferase makes it an interesting alternative for reporter genes that are conventionally used in yeast, such as lacZ. Copyright © 2003 John Wiley & Sons, Ltd.
MIG1‐dependent and MIG1‐independent regulation of GAL gene expression in Saccharomyces cerevisiae: role of Imp2p
Authors: Alberti Adriana , Lodi Tiziana , Ferrero Iliana , Donnini Claudia 
Published: October 2003

AbstractImp2p (Yil154c) is a transcriptional activator involved in glucose derepression of the maltose, galactose and raffinose utilization pathways and in resistance to thermal, oxidative or osmotic stress. We analysed the role of Imp2 in the regulation of GAL genes. Imp2 was shown to have a positive effect on glucose derepression of Leloir pathway genes and their activator gene GAL4. The effect of Imp2 on galactose metabolism was shown to be partially dependent on Mig1p. The Mig1‐independent role depends on Nrg1p. However, disruption of both MIG1 and NRG1 only partially relieves the glucose repression of GAL genes in the Δimp2 mutant, indicating that Imp2 must also have other function(s). Moreover, the interaction between IMP2 and GAL6/BLH1, a recently isolated gene involved in the regulation of GAL genes that shares with Imp2 the ability to protect cells from the glycopeptide bleomycin, was also analysed. The results suggest a major role of Imp2 in a GAL6‐independent pathway. Copyright © 2003 John Wiley & Sons, Ltd.
Role of the non‐respiratory pathways in the utilization of molecular oxygen by Saccharomyces cerevisiae
Authors: Rosenfeld Eric , Beauvoit Bertrand 
Published: October 2003

AbstractSaccharomyces cerevisiae is a facultative anaerobe devoid of mitochondrial alternative oxidase. In this yeast, the structure and biogenesis of the respiratory chain, on the one hand, and the functional interactions of oxidative phosphorylation with the cellular energetic metabolism, on the other, are well documented. However, to our knowledge, the molecular aspects and the physiological roles of the non‐respiratory pathways that utilize molecular oxygen have not yet been reviewed. In this paper, we review the various non‐respiratory pathways in a global context of utilization of molecular oxygen in S. cerevisiae. The roles of these pathways are examined as a function of environmental conditions, using either physiological, biochemical or molecular data. Special attention is paid to the characterization of the so‐called ‘cyanide‐resistant respiration’ that is induced by respiratory deficiency, catabolic repression and oxygen limitation during growth. Finally, several aspects of oxygen sensing are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
The ICL1 gene of Pichia pastoris, transcriptional regulation and use of its promoter
Authors: Menendez Javier , Valdes Iris , Cabrera Nelson 
Published: October 2003

AbstractWe cloned and characterized a gene encoding isocitrate lyase from the methylotrophic yeast Pichia pastoris. This gene was isolated from a P. pastoris genomic library using a homologous PCR hybridization probe, amplified with two sets of degenerate primers designed from conserved regions in yeast isocitrate lyases. The cloned gene was sequenced and consists of an open reading frame of 1563 bp encoding a protein of 551 amino acids. The molecular mass of the protein is calculated to be 60.6 kDa with high sequence similarity to isocitrate lyase from other organisms. There is a 64% identity between amino acid sequences of P. pastoris Icl and Saccharomyces cerevisiae Icl. Northern blot analyses showed that, as in S. cerevisiae, the steady‐state ICL1 mRNA levels depend on the carbon source used for cell growth. Expression in P. pastoris of the dextranase gene (dexA) from Penicillium minioluteum under control of the ICL1 promoter proved that PICL1 is a good alternative for the expression of heterologous proteins in this methylotrophic yeast. The sequence presented here has been deposited in the EMBL data library under Accession No. AJ272040. Copyright © 2003 John Wiley & Sons, Ltd.
Ter Linde JJM, Régnacq M and Steensma HY. 2003. Transcriptional regulation of YML083c under aerobic and anaerobic conditions. Yeast20: 439–454.
Authors: Ter Line J. J. M. , Régnacq M , Steensma H. Y. 
Published: October 2003

AbstractThe original article to which this Erratum refers was published in Yeast 20: 439–454. Copyright © 2003 John Wiley & Sons, Ltd.
Expression in Escherichia coli of a recombinant adenosine kinase from Saccharomyces cerevisiae: purification, kinetics and substrate analyses
Authors: Barrado Patricia , Rodríguez María José , Jiménez Antonio , Lobato María Fernández 
Published: October 2003

AbstractThe Saccharomyces cerevisiae ADO1 gene is known to encode a homologue of eukaryotic adenosine kinases. This gene was expressed in Escherichia coli as a recombinant protein fused to a polyhistidine tag by using the rhamnose‐inducible bacterial promoter rhaB. The recombinant protein was purified to apparent homogeneity and its ability to phosphorylate different substrates was evaluated. Adenosine (Km 3 µM) is its primary substrate. In addition, it also phosphorylates, albeit less efficiently, 3′‐deoxyadenosine (cordycepin; Km 1.84 mM) and 3′‐amino‐3′‐deoxyadenosine (Km 0.26 mM). Other kinetic properties of the recombinant enzyme have also been determined. Copyright © 2003 John Wiley & Sons, Ltd.