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71.
To elucidate the function of MAS-related GPCR, member D (MRGD) in cancers, we investigated the in vitro and in vivo oncogenic function of MRGD using murine fibroblast cell line NIH3T3 in which MRGD is stably expressed. The expression pattern of MRGD in clinical samples was also analyzed. We found that overexpression of MRGD in NIH3T3 induced focus formation and multi-cellular spheroid formation, and promoted tumors in nude mice. In other words, overexpression of MRGD in NIH3T3 induced the loss of contact inhibition, anchorage-independent growth and in vivo tumorigenesis. Furthermore, it was found that the ligand of MRGD, beta-alanine, enhanced spheroid formation in MRGD-expressing NIH3T3 cells. From investigation of clinical cancer tissues, we found high expression of MRGD in several lung cancers by immunohistochemistry as well as real time PCR. Based on these results, MRGD could be involved in tumorigenesis and could also be a novel anticancer drug target.  相似文献   
72.
73.
Kinship amongClethrionomys rufocanus was investigated during the winter of 1992/93 in a 3-ha enclosure using both molecular and catch-mark-release techniques. Forty-six adult voles (22 males and 24 females) having high heterozygosities, which were collected from several natural populations, were released into the enclosure on 29 September 1992. Most fall-born individuals of both sexes stayed in their natal site during the non-breeding period (December–March), although reproductively active females dispersed during the fall breeding season (October–November). These philopatric individuals aggregated and formed an maternal family in the winter. Several females which failed to reproduce were solitary during this season. Some individuals which were derived from several families also aggregated into a mixed lineage group. Survival rate of fall-born voles from earlier litters was higher than that from later ones. Maternal families broke up soon after the onset of spring reproduction. Most females established a territory near the wintering site and made a kincluster, in which close relatives neighbored each other. Maternal families in winter bring about female kin-clusters in spring, which may influence reproductive output in the breeding season.  相似文献   
74.
Increased matrix metalloproteinase-12 (MMP-12) has been implicated in atherosclerosis and many other inflammatory processes. To define MMP-12 functions in vivo, we generated transgenic rabbits that expressed human (h) MMP-12 gene under the control of a macrophage-specific promoter, the human scavenger receptor promoter. Two transgenic founder rabbits were found to have hMMP-12 transgene integration by Southern blot analysis. hMMP-12 mRNA was expressed in peritoneal and alveolar macrophages, and in tissues enriched in macrophages in transgenic rabbits. High levels of hMMP-12 protein were detected in the conditioned media of cultured peritoneal and alveolar macrophages from transgenic rabbits. Zymography showed that hMMP-12 secreted from macrophages possessed enzymatic activity toward β-casein. To evaluate the expression of hMMP-12 in inflammatory sites, we used carrageenan-induced granulomas as an in vivo model for tissue macrophages and foam cells. Granuloma size in transgenic rabbits was significantly increased compared to that in control rabbits, and histological examination revealed that granulomas of transgenic rabbits were enriched in macrophages associated with increased hMMP-12 expression. We believe that this transgenic rabbit model with increased expression of hMMP-12 may become a useful model for further mechanistic studies of MMP-12 in inflammatory diseases and cancer invasion; it is also an ideal model for testing the in vivo action of MMP-12 inhibitors.  相似文献   
75.
Allelic distributions of Thy-1, Ly-l, and Ly-2 antigens in wild mice are characteristic of each Mus musculus subspecies. Eastern mice (M.m.molossinus, M.mmusculus, M.m.castaneus, M.m.bactrianus) express the Thy-1.1 antigen, whereas Western mice (M.m. domesticus, M.m.brevirostris) express the Thy-1.2. All mice from wild populations examined in this survey express the Ly-1.2. The Ly-2.1 is distributed in Eastern mice and some Western mice, and the Ly-2.2 is found in the remaining Western mice. Allelic distributions of these antigens were also examined in two other species, Mus spretus and Mus spicilegus. Allelic constitutions of Thy-1 and Ly-1 in these species are similar to those of Eastern mice. Some M.spicilegus, however, express the Ly-1.1 antigen. This antigenic type is not found in M.musculus. Some Eastern mice related to M.m.castaneus react weakly to Ly-1.2-specific and Ly-2.1-specific monoclonal antibodies in both the complement-mediated cytotoxicity test and the absorption test. These results suggest that M.m.castaneus has unique alleles in the Ly-1 and Ly-2 loci.  相似文献   
76.

Background

Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults.

Methods

We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability).

Results and Discussion

Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults.

Conclusions

Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields.

Trial Registration

UMIN Clinical Trial Registry 000005618.  相似文献   
77.
The difference between the speed of simple cognitive processes and the speed of complex cognitive processes has various psychological correlates. However, the neural correlates of this difference have not yet been investigated. In this study, we focused on working memory (WM) for typical complex cognitive processes. Functional magnetic resonance imaging data were acquired during the performance of an N-back task, which is a measure of WM for typical complex cognitive processes. In our N-back task, task speed and memory load were varied to identify the neural correlates responsible for the difference between the speed of simple cognitive processes (estimated from the 0-back task) and the speed of WM. Our findings showed that this difference was characterized by the increased activation in the right dorsolateral prefrontal cortex (DLPFC) and the increased functional interaction between the right DLPFC and right superior parietal lobe. Furthermore, the local gray matter volume of the right DLPFC was correlated with participants' accuracy during fast WM tasks, which in turn correlated with a psychometric measure of participants' intelligence. Our findings indicate that the right DLPFC and its related network are responsible for the execution of the fast cognitive processes involved in WM. Identified neural bases may underlie the psychometric differences between the speed with which subjects perform simple cognitive tasks and the speed with which subjects perform more complex cognitive tasks, and explain the previous traditional psychological findings.  相似文献   
78.
Cembrane-type diterpenoids, 13,18,20-epi-iso-chandonanthone (1) and (8E)-4α-acetoxy-12α,13α-epoxycembra-1(15),8-diene (2), two fusicoccane-type diterpenoids, fusicoauritone 6α-methyl ether (3) and 6β,10β-epoxy-5β-hydroxyfusicocc-2-ene (4) and a zierane sesquiterpene γ-lactone, chandolide (5) were isolated from the Tahitian liverwort Chandonanthus hirtellus (Web.) Mitt., together with eight known diterpenoids, chandonanthine (6), fusicogigantone A (7), fusicogigantone B (8), fusicogigantepoxide (9), anadensin (10), fusicoauritone (11), ent-verticillol (12) and ent-epi-verticillol (13). Their structures were established by a combination of extensive NMR spectroscopy and/or X-ray crystallographic analyses. Compounds 1, 5 and 10 showed weak cytotoxic activity against HL-60. Compound 3 also indicated weak cytotoxic activity against KB cell lines.  相似文献   
79.
This study aimed to examine the roles of reactive oxygen species (ROS) in cisplatin treatment of human prostate cancer cells; hormone-sensitive LNCaP and hormone-refractory PC3 and DU145 cells. Intracellular levels of ROS and H(2)O(2) were measured and visualized using specific fluorescent probes. NADPH oxidase (NOX) activity was detected by lucigenin chemiluminescence assay. Expression levels of NOX isoforms were determined by semi-quantitative RT-PCR. Cisplatin treatment increased the intracellular levels of ROS and H(2)O(2) in three prostate cancer cell lines. The increase was transient and robust in hormone-sensitive LNCaP cells compared with hormone-refractory PC3 and DU145 cells. Consistent with these findings, the NOX activity induced by cisplatin was higher in LNCaP cells than in PC3 and DU145 cells. Expression pattern of NOX isoforms varied among three cell lines and the NOX activity was independent of NOX expression. Taken together, we have shown that cisplatin induces production of ROS and H(2)O(2) via NOX activation in human prostate cancer cell lines, which is most prominent in hormone-sensitive LNCaP cells.  相似文献   
80.
The balance between androgens and estrogens is very important in the development of the prostate, and even small changes in estrogen levels, including those of estrogen-mimicking chemicals, can lead to serious changes. Bisphenol A (BPA), an endocrine-disrupting chemical, is a well-known, ubiquitous, estrogenic chemical. To investigate the effects of fetal exposure to low-dose BPA on the development of the prostate, we examined alterations of the in situ sex steroid hormonal environment in the mouse urogenital sinus (UGS). In the BPA-treated UGS, estradiol (E(2)) levels and CYP19A1 (cytochrome P450 aromatase) activity were significantly increased compared with those of the untreated and diethylstilbestrol (DES)-treated UGS. The mRNAs of steroidogenic enzymes, Cyp19a1 and Cyp11a1, and the sex-determining gene, Nr5a1, were up-regulated specifically in the BPA-treated group. The up-regulation of mRNAs was observed in the mesenchymal component of the UGS as well as in the cerebellum, heart, kidney, and ovary but not in the testis. The number of aromatase-expressing mesenchymal cells in the BPA-treated UGS was approximately twice that in the untreated and DES-treated UGS. The up-regulation of Esrrg mRNA was observed in organs for which mRNAs of steroidogenic enzymes were also up-regulated. We demonstrate here that fetal exposure to low-dose BPA has the unique action of increasing in situ E(2) levels and CYP19A1 (aromatase) activity in the mouse UGS. Our data suggest that BPA might interact with in situ steroidogenesis by altering tissue components, such as the accumulation of aromatase-expressing mesenchymal cells, in particular organs.  相似文献   
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