bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyaniline. Preparation of a conducting polymer(IUPAC Technical Report)
Authors: Stejskal J. , Gilbert R. G. 
Published: October 2007

Abstract
Eight persons from five institutions in different countries carried out polymerizations of aniline following the same preparation protocol. In a "standard" procedure, aniline hydrochloride was oxidized with ammonium peroxydisulfate in aqueous medium at ambient temperature. The yield of polyaniline was higher than 90 % in all cases. The electrical conductivity of polyaniline hydrochloride thus prepared was 4.4 ± 1.7 S cm-1 (average of 59 samples), measured at room temperature. A product with defined electrical properties could be obtained in various laboratories by following the same synthetic procedure. The influence of reduced reaction temperature and increased acidity of the polymerization medium on polyaniline conductivity were also addressed. The conductivity changes occurring during the storage of polyaniline were monitored. The density of polyaniline hydrochloride was 1.329 g cm-3. The average conductivity of corresponding polyaniline bases was 1.4 x10­8 S cm-1, the density being 1.245 g cm-1. Additional changes in the conductivity take place during storage. Aging is more pronounced in powders than in compressed samples. As far as aging effects are concerned, their assessment is relative. The observed reduction in the conductivity by ~10 % after more than one-year storage is large but, compared with the low conductivity of corresponding polyaniline (PANI) base, such a change is negligible. For most applications, an acceptable level of conductivity may be maintained throughout the expected lifetime.
Grid computing and bioinformatics development. A case study on the Oryza sativa (rice) genome
Authors: Rungsarityotin Wasinee , Khiripet Noppadon , Tanpraset Chularat , Chitradon Royol 
Published: October 2007

Abstract
The bioinformatics research area is now faced with a mountain of ever-increasing and distributed information. For example, finding a single gene of the Oryza sativa (rice) genome one must spend weeks, if not months, wandering through approximately 40 million base pairs. These data are scattered in many data repositories. Thus, not only do we need an efficient tool to visualize and analyze DNA data, but the integration and exchange of information on a particular gene or coding regions from different international collaborative databases needs to be done in a careful, but robust manner as well. This research suggests a feasible means to overcome these problems by employing two main technologies. To support the exchange and communication between several sources of data, the grid database technology will be employed on the fast Internet2 backbone. Then, XML-based DNA data will be transported between collaborative sources for further analysis and representation. A preliminary version of our Web-based viewer for the XML data of the Oryza sativa genome is presented to illustrate the idea.
Definitions relating to stereochemically asymmetric polymerizations (IUPAC Recommendations 2001)
Authors: Hatada K. , Kahovec J. , Barón Máximo , Horie K. , Kitayama T. , Kubisa P. , Moss G. P. , Stepto R. F. T. , Wilks E. S. 
Published: October 2007

Abstract
Asymmetric polymerization has been of interest to many academic and industrial polymer scientists, but no reference has been made by IUPAC explicitly to classification and definitions of reactions involving the asymmetric synthesis of polymers. This document presents definitions concerned with asymmetric and related polymerizations, with examples included to clarify the meaning of the definitions. Asymmetric polymerizations embrace two main categories, "asymmetric chirogenic polymerizations" and "asymmetric enantiomer-differentiating polymerizations".
Potentiometric selectivity coefficients of ion-selective electrodes. Part II. Inorganic anions (IUPAC Technical Report)
Authors: Umezawa Yoshio , Umezawa Kayoko , Bühlmann Philippe , Hamada Naoko , Aoki Hiroshi , Nakanishi Jun , Sato Moritoshi , Xiao Kang Ping , Nishimura Yukiko 
Published: October 2007

Abstract
Potentiometric selectivity coefficients, K
A,B
pot have been collected for ionophore-based ion-selective electrodes (ISEs) for inorganic anions reported during 1988-1998. In addition to the actual numerical values of K
A,B
pot together with the methods and conditions for their determination, response slopes, linear concentration (activity) ranges, chemical compositions, and ionophore structures for the ISE membranes are tabulated.
Potentiometric coefficients of ion-selective electrodes. Part III. Organic ions (IUPAC Technical Report)
Authors: Umezawa Yoshio , Buhlmann Phillipe , Umezawa Kayoko , Hamada Naoko 
Published: October 2007

Abstract
Potentiometric selectivity coefficients, K
A,B
pot, have been collected for ionophore-based ion-selective electrodes (ISEs) for organic ions reported during 1988-1998. In addition to the actual numerical values of K
A,B
pot together with the methods and conditions for their determination, response slopes, linear ranges, chemical compositions, and ionophore structures for the ISE membranes are tabulated.
Role of water in sweet taste chemoreception
Authors: Birch Gordon G. 
Published: October 2007

Abstract
The mechanistic understanding of sweet taste chemoreception has been advanced by the microscopic and macroscopic studies of sweetener­water interactions. This approach has led to the concept of water mobility as a key to interpreting sweetness. The apparent specific volume of a solution is a determinant of its taste quality, as sweetness is known to be confined to the range 0.51­0.71 cm3 g-1. Thus, the "ideal" quality of the sugars is presumed to be due to their occupancy of the center of this range (i.e., 0.618 cm3 g-1). Most sweeteners elicit off-tastes and flavors and exhibit different apparent specific volumes. This leads to the conclusion that taste quality is broadly determined by the packing characteristics of sweet molecules among water molecules and the compactness of their hydration shells, expressed as their apparent specific isentropic compressibilities. The role of water can, therefore, be applied in modern attempts to optimize sweet taste quality, and different food salts can be explored as useful taste modifiers. Salts interact more strongly with water structure than do any other taste solutes, and it emerges that the ionic charge density is an important criterion. Such studies show how sweetener formulations are likely to improve within the next decade.
Homology-based model of the extracellular domain of the taste receptor T1R3
Authors: Walters D. Eric 
Published: October 2007

Abstract
The extracellular ligand binding domain of the sweet receptor T1R3 has been homology-modeled on the basis of the crystal structure of the metabotropic glutamate receptor (mGluR1). The region of the model that corresponds to the ligand binding site of mGluR1 has numerous polar and charged side-chains, consistent with expectations for a site that would respond to poly hydroxy compounds such as mono- and disaccharides. Docking studies show that proposed active conformations of the high-potency sweeteners neotame, superaspartame, and SC-45647 could interact favorably in this binding site, forming ion pairs or ionic hydrogen bonds with His-163, Glu-318, and His-407, in addition to hydrophobic interactions with numerous nonpolar side-chains.
Molecular mechanisms of taste transduction
Authors: Margolskee Robert F. 
Published: October 2007

Abstract
Taste transduction is a specialized form of signal transduction by which taste receptor cells (TRCs) encode at the cellular level information about chemical substances encountered in the oral environment (so-called tastants). Bitter and sweet taste transduction pathways convert chemical information into a cellular second messenger code utilizing cyclic nucleotides, inositol trisphosphate, and/or diacyl glycerol. These messengers are components of signaling cascades that lead to TRC depolarization and Ca++ release. Bitter and sweet taste transduction pathways typically utilize taste-specific or taste-selective seven transmembrane-helix receptors, G proteins, effector enzymes, second messengers, and ion channels. The structural and chemical diversity of tastants has led to the need for multiple transduction mechanisms. Through molecular cloning and data mining, many of the receptors, G proteins, and effector enzymes involved in transducing responses to bitter and sweet compounds are now known. New insights into taste transduction and taste coding underlying sweet and bitter taste qualities have been gained from molecular cloning of the transduction elements, biochemical elucidation of the transduction pathways, electrophysiological analysis of the function of taste cell ion channels, and behavioral analysis of transgenic and knockout models.
Ion channels and second messengers involved in transduction and modulation of sweet taste in mouse taste cells
Authors: Sugimoto Kumiko , Shigemura Noriatsu , Yasumatsu Keiko , Ohta Rie , Nakashima Kiyohito , Kawai Kirio , Ninomiya Yuzo 
Published: October 2007

Abstract
Leptin, a hormone released from the adipose tissue, inhibits food intake and increases energy expenditure. We have found a novel function of leptin as a modulator of sweet taste sensitivity in mice. In lean normal mice, the gustatory nerve responses to sweet stimuli were selectively suppressed depending on plasma leptin level after an intraperitoneal injection of recombinant leptin. Patch-clamp studies using isolated taste cells of lean mice showed that extracellular leptin enhanced K+ currents of sweet-responsive taste cells, which led to membrane hyperpolarization and a reduction of sweetener-induced depolarization. Reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization analyses demonstrated specific expression of mRNA of the long-form functional leptin receptor (Ob-Rb) in taste tissue and cells of lean mice. The genetically diabetic db/db mice, which have defects in Ob-Rb, demonstrated neither a suppression of gustatory neural responses to sweeteners nor an increment of whole-cell K+ conductance of taste cells even with high doses of leptin. These results suggest that Ob-Rb is specifically expressed in sweet-responsive taste cells of lean mice and that leptin suppresses sweetener-induced depolarization via activation of K+ channels, leading to a decrease in impulses of sweet-best fibers. The enhanced sweet responses of db/db mice may result from the lack of inhibitory modulation by leptin.
Specialization and phyletic trends of sweetness reception in animals
Authors: Glaser Dieter 
Published: October 2007

Abstract
During the last decades, the comparison in various animal species of their gustatory responses to compounds eliciting a sweet taste in humans has extended our knowledge of the great biodiversity of the taste responses and evidenced some specialization and/or phyletic trends within species. Our interest was focused on responses to natural sugars, polyols, and naturally occurring sweeteners, but also on various artificial sweetening compounds, including the very powerful guanidine sweeteners. New results obtained with kangarooswhich originated about 130 MYAhave shown that their sweetness receptor is not designed to taste any of the artificial sweeteners tested. Therefore, the ability to taste complicated artificial sweeteners must have evolved later in higher developed mammals, about 100 million years ago.
Drosophila sweet taste receptor
Authors: Isono Kunio , Ueno Kohei , Ohta Masayuki , Morita Hiromi 
Published: October 2007

Abstract
Like the Sac locus controlling sugar sensitivity in mice, the taste gene Tre of the fruitfly Drosophila was discovered in wild populations as a genetic dimorphism controlling gustatory sensitivity to a sugar trehalose. By activating a P-element transposon near the gene locus we obtained induced Tre mutations and analyzed the associated changes in gene organizations and the mRNA expressions. The analysis showed that Tre is identical to Gr5a, a gene that belongs to a novel seven-transmembrane receptor family expressed in chemosensory neurons and predicted to encode chemosensory receptors. Thus, Gr5a is a candidate sweet taste receptor in the fly. An amino acid substitution in the second intracellular loop domain was identified to be functionally correlated with the genetic dimorphism of Tre. Since Tre controls sweet taste sensitivity to a limited subset of sugars, other Gr genes phylogenetically related to Tre may also encode sweet taste receptors. Those candidate sweet taste receptors, however, are phylogenetically distinct from vertebrate sweet taste receptors, suggesting that the sweet taste receptors in animals do not share a common origin.
Isovanillyl sweeteners. From molecules to receptors
Authors: Bassoli Angela , Merlini Lucio , Morini Gabriella 
Published: October 2007

Abstract
Systematic modification of the structure of the sweet natural compound phyllodulcin, containing the isovanillyl glucophoric group, led to the synthesis of about 120 compounds. Features of the heterocyclic ring conferring high sweetness potency were identified. A strong increase in sweetness was obtained by the introduction of sulfur atoms in the ring and by separation of the enantiomers. Results of the quantitative structure­activity relationship (QSAR) studies on this series are reported. Application of the pseudoreceptor modeling approach afforded a three-dimensional binding site model for isovanillyl sweeteners. Extension of this methodology to a large group of structurally diverse compounds, including the commonly used sweeteners, gave a general pseudoreceptor for the sweet compounds, consisting of 16 amino acids. This pseudoreceptor, which has the peculiarity of giving a semiquantitative evaluation of the sweetness intensity, could be used as a valid tool to model the ligand­receptor interactions and to suggest some clues about the identification of a possible binding site once the receptor protein(s) are obtained.
Computational studies of sweet-tasting molecules
Authors: Barker Jodie S. , Hattotuwagama Channa K. , Drew Michael G. B. 
Published: October 2007

Abstract
Quantitative structure­activity relationships (QSARs) are developed for two separate families of sweet-tasting molecules for which sweetness values relative to sucrose (RS) have been measured. For these two families of sucrose and guanidine derivatives, the molecules were divided into training and test sets. Linear multiple regression equations have been generated to relate separately log(RS) to two types of parameters, namely molecular descriptors and energies derived via molecular field analysis (MFA). The parameters used in the development of linear multiple regression equations were selected by the genetic algorithm. The equations obtained show high predictive quality, which is confirmed by statistical parameters obtained with the test sets.
The data for these two families were then combined with data from two other families previously studied, namely the sulfamates and isovanillates, to make a set of 149 compounds. These molecules were also studied by QSAR methods. The generated equations show remarkable predictive power, and the quality of the results suggest that the mechanism of sweet taste receptor is similar and, therefore, that there could well be only one receptor site for sweet taste, particularly for the four sweet taste families considered in this work.
Search for new sulfonyl-containing glucophores
Authors: Polanski Jaroslaw , Jarzembek Krystyna 
Published: October 2007

Abstract
A number of sweeteners contain the sulfur atom and a sulfonyl group. In our current search for new glucophores, several new compounds containing a sulfonyl group were obtained. Synthetic targets have been found both by intuitive modifications of the structural motifs of the known sweet compounds and by the use of molecular modeling techniques. We developed the efficient synthetic routes yielding these compounds and obtained a number of these analogs. We have evaluated the taste quality of the amides and sulfonylated amino acids, finding out that almost all of them are bitter actives. We are now performing basic toxicological tests preceding the systematic taste study within the tetrazoles obtained.
Structure­taste relationships of the sweet protein monellin
Authors: Kohmura Masanori , Mizukoshi Toshimi , Nio Noriki , Suzuki Ei-ichiro , Ariyoshi Yasuo 
Published: October 2007

Abstract
Structure­taste relationship studies were carried out by chemically synthesizing monellin and its analogs. Replacement of the AspB7 by l-2-aminobutyric acid, Gly and d-Asp resulted in complete loss of sweetness. Replacement of IleB6 and IleB8 by different amino acids resulted in a significant decrease of sweetness, or complete loss of sweetness. Comparison of short- and long-range nuclear Overhauser effects (NOEs) and chemical shifts between monellin and [AbuB7]monellin showed no marked differences except for the region of the AspB7. Thus, the complete loss of sweetness in [AbuB7]monellin is caused by the lack of free β-carboxyl group in the AspB7 and not by a result of major disruption in the overall 3-dimensional structure. These results suggested that the free β-carboxyl group of the AspB7 would possibly bind to the receptor site through ionic bonding and trigger the sensation of intense sweet taste, and IleB6 and/or IleB8 would be involved in the hydrophobic interaction with the receptor site. Selectively labeled monellin was synthesized by the solid-phase method by incorporating 15N-labeled amino acids into 10 key residues including AspB7. Relaxation analysis shows that AspB7 is the most flexible of these 10 residues. The flexibility of the active site may be important for receptor binding.
Present status and future of functional oligosaccharide development in Japan
Authors: Nakakuki Teruo 
Published: October 2007

Abstract
Several oligosaccharides such as glycosylsucrose, fructo-oligosaccharides, malto-oligosaccharides, isomalto-oligosaccharides (branched-oligosaccharides), galacto-oligosaccharides, xylo-oligosaccharides, isomaltulose (palatinose), and lactosucrose have been produced on an industrial scale. Recent developments in industrial enzymology have made possible a series of new starch oligosaccharides such as β-1,6 linked gentio-oligosaccharides, α,α-1,1 linked trehalose, α-1,3 linked nigero-oligosaccharides, and branched-cyclodextrins. Some new sweeteners, including trehalose and nigero-oligosaccharides, are being developed as food ingredients with physiologically unique functions such as superoxide dismutase-like activity and immunological activity. Also, soybean oligosaccharides containing raffinose, stachyose, and other oligosaccharides mentioned above are now used in beverages, confectionery, bakery products, yogurts, daily products, and infant milk. In 1991, the Japanese government legislated for Foods for Specified Health Use (FOSHU). FOSHU increased the total to 223 items of which more than 50 % incorporate oligosaccharides as the functional components. Furthermore, the Ministry of Health, Labor, and Welfare published the proposal for a new system named Foods with Health Claims (FHC), which was carried out in April 2002.
Digestion, absorption, fermentation, and metabolism of functional sugar substitutes and their available energy
Authors: Oku Tsuneyuki , Nakamura Sadako 
Published: October 2007

Abstract
Many kinds of oligosaccharides and sugar alcohols have been newly developed as bulking sugar substitutes that have beneficial health effects. A sugar substitute that is not digested and absorbed in the small intestine reaches the large intestine, where it is completely fermented by intestinal bacteria and produces short-chain fatty acids, which are converted to energy. The available energy of a nondigestible sugar substitute, which is completely fermented by intestinal microbes, is estimated as approximately 2 kcal/g.
On the other hand, a sufficiently high ingestion of nondigestible sugar substitutes regularly causes overt diarrhea in human and animals. However, the diarrhea disappears within a few days because intestinal microbes, which readily utilize these saccharides, increase during ingestion. The maximum permissible dose, by which transitory diarrhea is not caused by the ingestion of nondigestible sugar substitutes, is estimated as approximately 0.3 g per kg body weight in single ingestion for Japanese adults. The value is varied by some factors, such as separate ingestion, repeat ingestion, test substance, and body condition, etc.
Novel physiological functions of oligosaccharides
Authors: Hirayama Masao 
Published: October 2007

Abstract
This paper reviews the evidence for novel physiological functions of oligosaccharides. A history of the research and development and the types of health benefits are discussed. A key property of the physiological functions lies in the indigestibility of oligosaccharides, which gives rise to fermentation in the large intestine, followed by an increase of Bifidobacteria and short-chain fatty acid (SCFA) production. This property leads to several kinds of physiological functions, classified into three types of health benefits. The first is the improvement of gastrointestinal conditions, including a normal stool frequency, less constipation, and healthy intestinal microflora. The second is the promotion of mineral absorption, including an increase of bone density and relief of anemia. The third is an immunomodulation effect, such as allergy and cancer prevention.
Role of sweeteners in the etiology and prevention of dental caries
Authors: Hamada Shigeyuki 
Published: October 2007

Abstract
Dental caries is a multifactorial disease that is caused by an interplay of three major factors, i.e., teeth, cariogenic bacteria, and fermentable sugars. Streptococcus mutans and S. sobrinus, collectively termed mutans streptococci (MS), are principal causative agents of dental caries. Initial MS-tooth surface attachment is followed by firm and irreversible adhesion of MS to the tooth surface, accompanied by the synthesis of water-insoluble glucan from sucrose via enzymatic action of glucosyltransferases (GTases). MS induce severe dental caries in rats fed on a high-sucrose diet. Epidemiological surveys indicate that frequent sucrose intakes are associated with high prevalence of dental caries in humans. In contrast, dietary sucrose restrictions and/or use of nonfermentable sucrose substitutes clearly influence the GTase activities of MS, resulting in decreased caries development. Structural isomers of sucrose (i.e., disaccharides composed of glucose and fructose with different linkages) will not function as substrates for GTases of MS, nor be utilized as energy sources by MS. Palatinose and trehalulose are included in this category, and are produced in commercial scales in Japan. Glucose oligomers containing α-1, 6 and/or α-1, 4 linkages are found to inhibit glucan synthesis by MS from sucrose, although these oligomers are hydrolyzed by MS to release acids. Lastly, sugar alcohols, including maltitol and palatinit, are useful as noncaries-inducing sweeteners.
Antidiabetogenic constituents from several natural medicines
Authors: Matsuda Hisashi , Morikawa Toshio , Yoshikawa Masayuki 
Published: October 2007

Abstract
In the course of our studies on antidiabetogenic and antidiabetic principles of natural medicines and medicinal foodstuffs, we have isolated salacinol and kotalanol with unique thiosugar sulfonium sulfate inner salt structures from the antidiabetic Ayurvedic traditional medicines, Salacia reticulata and S. oblonga. Salacinol and kotalanol showed potent inhibitory activities against intestinal α-glucosidase, and also inhibitory effects of salacinol on the increase in serum glucose levels in maltose- and sucrose-loaded rats were found to be more potent than those of acarbose. In addition, various flavonoids with potent inhibitory activities against rat lens aldose reductase such as quercitrin desmanthin-1 and guaijaverin were isolated from Myrcia multiflora and several natural medicines, and some structural requirements of flavonoids for aldose reductase inhibitory activity were clarified.