80 research outputs found
Implication of Tryptophan 2,3-Dioxygenase and its Novel Variants in the Hippocampus and Cerebellum During the Developing and Adult Brain
Tryptophan 2,3-dioxygenase (TDO) is a first and rate-limiting enzyme for the kynurenine pathway of tryptophan metabolism. Using Tdoâ/â mice, we have recently shown that TDO plays a pivotal role in systemic tryptophan metabolism and brain serotonin synthesis as well as emotional status and adult neurogenesis. However, the expression of TDO in the brain has not yet been well characterized, in contrast to its predominant expression in the liver. To further examine the possible role of local TDO in the brain, we quantified the levels of tdo mRNA in various nervous tissues, using Northern blot and quantitative real-time RT-PCR. Higher levels of tdo mRNA expression were detected in the cerebellum and hippocampus. We also identified two novel variants of the tdo gene, termed tdo variant1 and variant2, in the brain. Similar to the known TDO form (TDO full-form), tetramer formation and enzymatic activity were obtained when these variant forms were expressed in vitro. While quantitative real-time RT-PCR revealed that the tissue distribution of these variants was similar to that of tdo full-form, the expression patterns of these variants during early postnatal development in the hippocampus and cerebellum differed. Our findings indicate that in addition to hepatic TDO, TDO and its variants in the brain might function in the developing and adult nervous system. Given the previously reported associations of tdo gene polymorphisms in the patients with autism and Tourette syndrome, the expression of TDO in the brain suggests the possible influence of TDO on psychiatric status. Potential functions of TDOs in the cerebellum, hippocampus and cerebral cortex under physiological and pathological conditions are discussed
THE EFFECTS OF CONSUMER PERCEPTION ON STORE IMAGE AND PRIVATE LABEL: COMPARATIVE STUDY BETWEEN TAIWAN AND JAPAN
In this paper, we report on empirical results on the relation between a private label and store image in Taiwan and Japan. Private labels are generally defined as goods which shall be sold in a specific retailer as the retailerâs original brand. Retailers preferred to sell private labels because the private label cannot be sold in other retail stores, and can contribute to the retailerâs profit. Private labels, however, have been regarded as cheaper goods than national brands. Indeed, average prices of private labels are always cheaper than national brandsâ are. So typically, when consumers choose a private label, just for price reason.
Recently in Japan, consumer perceptions to private labels are gradually changing. This change is attributed in some extent to new product development by convenience stores. These private labels are placed at better locations than national brands are in the stores. These private labels are no longer regarded as cheaper goods, rather as âthe only-one
goodsâ at the specific retail store. In this paper, we examine how the consumersâ perceptual characteristics and a storeâs image influence private label attitude and purchase intention. We conducted two surveys of 350 and 670 consumers both in Taiwan and Japan, respectively. We found that consumer perceptual characteristics and store image both impact on purchase intention, but that consumer perceptual characteristics have a stronger effect on private label attitude than store image. In addition, store image plays the role of antecedent in consumer perceptual characteristics
THE EFFECTS OF CONSUMER PERCEPTION ON STORE IMAGE AND PRIVATE LABEL: COMPARATIVE STUDY BETWEEN TAIWAN AND JAPAN
In this paper, we report on empirical results on the relation between a private label and store image in Taiwan and Japan. Private labels are generally defined as goods which shall be sold in a specific retailer as the retailerâs original brand. Retailers preferred to sell private labels because the private label cannot be sold in other retail stores, and can contribute to the retailerâs profit. Private labels, however, have been regarded as cheaper goods than national brands. Indeed, average prices of private labels are always cheaper than national brandsâ are. So typically, when consumers choose a private label, just for price reason.
Recently in Japan, consumer perceptions to private labels are gradually changing. This change is attributed in some extent to new product development by convenience stores. These private labels are placed at better locations than national brands are in the stores. These private labels are no longer regarded as cheaper goods, rather as âthe only-one
goodsâ at the specific retail store. In this paper, we examine how the consumersâ perceptual characteristics and a storeâs image influence private label attitude and purchase intention. We conducted two surveys of 350 and 670 consumers both in Taiwan and Japan, respectively. We found that consumer perceptual characteristics and store image both impact on purchase intention, but that consumer perceptual characteristics have a stronger effect on private label attitude than store image. In addition, store image plays the role of antecedent in consumer perceptual characteristics
Tryptophan 2,3-dioxygenase is a key modulator of physiological neurogenesis and anxiety-related behavior in mice
Although nutrients, including amino acids and their metabolites such as serotonin (5-HT), are strong modulators of anxiety-related behavior, the metabolic pathway(s) responsible for this physiological modulation is not fully understood. Regarding tryptophan (Trp), the initial rate-limiting enzymes for the kynurenine pathway of tryptophan metabolism are tryptophan 2,3-dioxygenase (TDO) and indoleamine 2,3-dioxygenase (IDO). Here, we generated mice deficient for tdo (Tdo-/-). Compared with wild-type littermates, Tdo-/- mice showed increased plasma levels of Trp and its metabolites 5-hydroxyindoleacetic acid (5-HIAA) and kynurenine, as well as increased levels of Trp, 5-HT and 5-HIAA in the hippocampus and midbrain. These mice also showed anxiolytic modulation in the elevated plus maze and open field tests, and increased adult neurogenesis, as evidenced by double staining of BrdU and neural progenitor/neuronal markers. These findings demonstrate a direct molecular link between Trp metabolism and neurogenesis and anxiety-related behavior under physiological conditions
Making and consuming characters
This paper shall introduce a new phenomenon about consumption. This is related to consumption of characters like Mickey Mouse and Hello, Kitty. The phenomenon appears prominently in Japan. In order to examine consumption of characters and the strategies for creating characters, we conducted a case study on a set of marketing strategies of a toy manufacturer in Japan. Traditionally, consumption research is asserted using the uni-methodological paradigm. The uni-methodological paradigm here means that researchers have a methodological exclusiveness stance to any other research approaches. Hirschman and Holbrook (1992) distinguish five non-interchangeable research approaches on consumer research. For
instance, from an economic point of view, consumption could be assumed as a problem solving method to increase utility. Baudrillard (1968, 1970) criticized this type of functional consumption. Researchers have often denied the other approaches competitive to their own approaches rather than incorporating them. Character consumption cannot be revealed by such an insulated research stance because consumers would like to consume characters for multidimensional reasons. They consume characters to enhance their utilities. In addition, characters stimulate consumersâ sentiments. The possession desire is satisfied by consuming characters. Possessing character goods can create small interest groups and stimulate communication among the group members. Consuming characters
is assumed to involve multidimensional aspects: functional, conspicuous, and semiotic consumption. As a result, once we try to understand character consumption, we have to employ the multidisciplinary approach in contrast to the unimethodological
paradigm. Through our case study, we revealed the distinctive marketing strategies in the business of characters. It is necessary for
marketers of character goods to regard character consumption as having functional, conspicuous, and semiotic aspects. We can find distinctive characteristics in the market research, product development, advertising, and communication strategies in the process of creating characters
Expression of tryptophan 2,3-dioxygenase in mature granule cells of the adult mouse dentate gyrus
New granule cells are continuously generated in the dentate gyrus of the adult hippocampus. During granule cell maturation, the mechanisms that differentiate new cells not only describe the degree of cell differentiation, but also crucially regulate the progression of cell differentiation. Here, we describe a gene, tryptophan 2,3-dioxygenase (TDO), whose expression distinguishes stem cells from more differentiated cells among the granule cells of the adult mouse dentate gyrus. The use of markers for proliferation, neural progenitors, and immature and mature granule cells indicated that TDO was expressed in mature cells and in some immature cells. In mice heterozygous for the alpha-isoform of calcium/calmodulin-dependent protein kinase II, in which dentate gyrus granule cells fail to mature normally, TDO immunoreactivity was substantially downregulated in the dentate gyrus granule cells. Moreover, a 5-bromo-2'-deoxyuridine labeling experiment revealed that new neurons began to express TDO between 2 and 4 wk after the neurons were generated, when the axons and dendrites of the granule cells developed and synaptogenesis occurred. These findings indicate that TDO might be required at a late-stage of granule cell development, such as during axonal and dendritic growth, synaptogenesis and its maturation
AN OPTIMIZATION-BASED APPROACH FOR GRASP POSTURE GENERATION OF DIGITAL HAND
ABSTRACT * Recently, as handheld information appliances, such as mobile phones, PDAs, have widely spread, the development of these appliances should pay more attention in their ergonomic design. However, the user tests for developing the "ergonomic" appliances are usually done by many real subjects testing a variety of these physical mockups, and the process of these tests usually requires the expensive cost and has to take a long time. So, we propose a software system of an automatic ergonomic assessment system for designing handheld information appliances by integrating the digital hand model with the 3D product model of the appliance. Our system has the following four feature functions for ergonomic assessment: 1) Generation of kinematically and geometrically accurate digital hand models with rich dimensional variation, 2) automatic grasp posture generation and evaluation of the posture stability by estimating the force-closure and the grasp quality, 3) automatic evaluation of ease of the finger motion in operating the user interface, 4) aiding the designers to re-design the housing shapes and user-interfaces in the product model. In this paper we propose a new optimization-based method the 2) of the above functions. As the objective function, we use the number of the contact points, the fit of the specific part of the hand surface for the feature edges of the product surface and the margin for the constraints on the joint angle limits of the figures. The experimental studies on the grasp posture generation for the digital camera indicate that more realistic grasp posture could be generated using the proposed * N14 W9, Kita-ku, Sapporo, Hokkaido 060-0814, Japan. Email: [email protected] optimization-based method than the one using our former method
Angioscopic Evaluation of Stabilizing Effects of Bezafibrate on Coronary Plaques in Patients With Coronary Artery Disease
Background Since long-term administrations of anti-hyperlipidemic
agents result in reduction in % stenosis or increase in
minimum lumen diameter (MLD) of stenotic coronary
segments, it is generally believed that anti-hyperlipidemic agents
stabilize vulnerable coronary plaques. However, recent pathologic
and angioscopic studies revealed that vulnerability of coronary
plaques is not related to severity of stenosis and the rims rather
than top of the plaques disrupt, and therefore, angiography is not
adequate for evaluation of vulnerability
Multicolor and multi-spot observations of Starlink's Visorsat
This study provides the results of simultaneous multicolor observations for
the first Visorsat (STARLINK-1436) and the ordinary Starlink satellite,
STARLINK-1113 in the , , , , , , , ,
, , , and bands to quantitatively investigate the extent to
which Visorsat reduces its reflected light. Our results are as follows: (1) in
most cases, Virorsat is fainter than STARLINK-1113, and the sunshade on
Visorsat, therefore, contributes to the reduction of the reflected sunlight;
(2) the magnitude at 550 km altitude (normalized magnitude) of both satellites
often reaches the naked-eye limiting magnitude ( 6.0); (3) from a blackbody
radiation model of the reflected flux, the peak of the reflected components of
both satellites is around the band; and (4) the albedo of the near infrared
range is larger than that of the optical range. Under the assumption that
Visorsat and STARLINK-1113 have the same reflectivity, we estimate the covering
factor, , of the sunshade on Visorsat, using the blackbody radiation
model: the covering factor ranges from . From
the multivariable analysis of the solar phase angle (Sun-target-observer), the
normalized magnitude, and the covering factor, the phase angle versus covering
factor distribution presents a moderate anti-correlation between them,
suggesting that the magnitudes of Visorsat depend not only on the phase angle
but also on the orientation of the sunshade along our line of sight. However,
the impact on astronomical observations from Visorsat-designed satellites
remains serious. Thus, new countermeasures are necessary for the Starlink
satellites to further reduce reflected sunlight.Comment: 31 pages, 9 figures, published in PAS
Arabidopsis RPT2a, 19S Proteasome Subunit, Regulates Gene Silencing via DNA Methylation
The ubiquitin/proteasome pathway plays a crucial role in many biological processes. Here we report a novel role for the Arabidopsis 19S proteasome subunit RPT2a in regulating gene activity at the transcriptional level via DNA methylation. Knockout mutation of the RPT2a gene did not alter global protein levels; however, the transcriptional activities of reporter transgenes were severely reduced compared to those in the wild type. This transcriptional gene silencing (TGS) was observed for transgenes under control of either the constitutive CaMV 35S promoter or the cold-inducible RD29A promoter. Bisulfite sequencing analysis revealed that both the transgene and endogenous RD29A promoter regions were hypermethylated at CG and non-CG contexts in the rpt2a mutant. Moreover, the TGS of transgenes driven by the CaMV 35S promoters was released by treatment with the DNA methylation inhibitor 5-aza-2âČ-deoxycytidine, but not by application of the inhibitor of histone deacetylase Trichostatin A. Genetic crosses with the DNA methyltransferase met1 single or drm1drm2cmt3 triple mutants also resulted in a release of CaMV 35S transgene TGS in the rpt2a mutant background. Increased methylation was also found at transposon sequences, suggesting that the 19S proteasome containing AtRPT2a negatively regulates TGS at transgenes and at specific endogenous genes through DNA methylation
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