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Abstract: Background/purpose: Recently, valine, which is one of the branched chain amino acids, has been reported to enhance liver regeneration after hepatectomy in the rat. The aim of this study was to investigate the effect of enteral valine supplementation on intestinal adaptation. Materials/methods: Seven-week-old male Lewis rats underwent a 90% small bowel resection. The rats were randomly divided into two groups: group V (valine-rich diet) and group S (standard rat chow), according to the diet. The rats were sacrificed at the operation day and on postoperative days (POD) 7, 14, 30, and 60. The metrics were body weight (BW), blood amino acids, urine organic acids, and morphology of the residual small intestine. Results: The BW and the intestinal wet weight, jejunal crypt depth, and proliferating cell nuclear antigen–positive cells in group V at POD 7 were significantly higher than those values in group S, while those in group V at POD 30 and 60 were smaller than those in group S. The urine methylmalonic acid (MMA) level in group V at POD 30 and 60 was much higher than in group S. Conclusion: Valine enhanced intestinal adaptation after massive small bowel resection in the acute phase. However, the long-term supplementation disturbed intestinal adaptation, which might be due to the high production of MMA. [Copyright &y& Elsevier]

Changes in gene expression are part of the homeostatic machinery with which cells respond to external stimuli or assaults. The activity of the early response transcriptional factor activator protein-1 (AP-1) can be modulated by a variety of environmental stimuli including those that alter the cellular oxidation/reduction status. This study investigates the activation of AP-1/DNA binding in the guinea-pig cochlea in response to acoustic overstimulation which produces reactive oxygen species. Electrophoretic mobility shift assays revealed that binding of AP-1 to its radiolabeled oligonucleotide probe markedly changed in nuclear extracts of inner ear tissues following intense noise exposure (4 kHz octave band, 115 dB, 5 h). AP-1/DNA binding increased in the organ of Corti and the lateral wall tissues immediately after the exposure, returning to near-baseline levels 5 h later. At 15 h after noise, a second peak of binding activity occurred in the organ of Corti whereas stria vascularis showed a lesser but more sustained activity. Binding in nuclear extracts from the spiral ganglion did not change. Incubation of nuclear extracts with antibodies against Fos/Jun family proteins prior to a supershift assay showed Fra-2 as a major component of the AP-1 complex immediately after the noise exposure. In the organ of Corti, Fra-2 immunoreactivity was localized to the middle turn, i.e. the region which is most affected by the 4-kHz octave band exposure. The results suggest the modulation of gene expression via the activation of AP-1 as a consequence of noise trauma but also demonstrate differential responses in cochlear tissues. [Copyright &y& Elsevier]

: BackgroundWe evaluated the effects of nucleosides (NS) and nucleotides (NT) on the rejection of rat allogeneic small intestinal transplants.: MethodsA 2-cm segment of jejunum from fetal Fischer rats (RT-1lvl) was transplanted at day 19 of gestation into the abdominal wall of 7-week-old Lewis rats (RT-1l) by a nonvascular technique. Two weeks before transplantation, recipient rats were separated into an NS–NT-free group and an NS–NT-supplemented group. At 2 days after transplantation, histologic study of the grafts was performed with hematoxylin–eosin staining and interleukin-2 (IL-2) production estimated in recipient blood using an ELISA method. The morphologic findings were graded in a blind fashion on a scale of 0 to 4, with 0 indicating an intact intestinal structure.: ResultsMean plasma IL-2 levels of the NS–NT-free group were significantly lower than those of the NS–NT-supplemented group. The mean rejection score of the NS–NT-free group was also significantly lower than that of the NS–NT-supplemented group.: ConclusionsAdministration of an NS–NT-free diet reduces acute rejection in rat small intestinal transplantations. [Copyright &y& Elsevier]

Abstract: Hippocampal neurogenesis occurs throughout life in mammals and has pivotal roles in brain functions. An enriched environment stimulates hippocampal neurogenesis, but the exact mechanisms are still unclear. The present study investigated the role of pituitary adenylate cyclase-activating polypeptide (PACAP) in adult hippocampal neurogenesis under standard or enriched rearing conditions. Rearing in the enriched conditions from 4-weeks old for 4-weeks increased the survival of newly divided cells in the subgranular zone and granule cell layer of the dentate gyrus of wild-type and PACAP-knockout (PACAP−/−) mice. The increase in the survival in the granule cell layer was less in PACAP−/− mice than in the wild-type mice. In contrast, the proliferation of newly divided cells in mice reared in the standard and enriched conditions did not differ between the wild-type and PACAP−/− mice. Regarding the differentiation of newborn cells in the dentate gyrus, most of the newly divided cells exhibited the neuronal phenotype in both the wild-type and PACAP−/− mice under standard and enriched conditions. These findings suggest that endogenous PACAP is partly involved in the survival of the enriched environment-induced generation, but not in the basal rate, of newborn cells in the dentate gyrus of the adult hippocampus. [ABSTRACT FROM AUTHOR]

Abstract: We studied the correlation between the motility and the mucosal histology of the small bowel seeking to detect rejection in an early stage by real-time monitoring using a swine model. Intestinal transplantation (ITx) was performed orthotopically using FK506 immunosuppression. The distal about 20 cm segment of the allograft was exteriorized as a Thiry-Vella stoma for biopsies. Strain gauge (SG) force transducers were attached to the graft for real-time monitoring of graft motility. Pigs without ITx were used as controls (group 1). Rejection was classified into four groups by histologic findings: nonrejection (group 2), mild rejection (group 3), moderate rejection (group 4), and severe rejection (group 5). Migrating motor complex (MMC) phase III was analyzed for the following parameters: duration, amplitude, interval, motility index, velocity, and frequency of propagation. In group 2, all parameters were almost the same as those for group 1. In contrast, groups 4 and 5 showed most parameters significantly lower than those in group 1. In group 3, the contractility of the MMC was not significantly altered, but the frequency of the propagation was decreased significantly. In conclusion, graft motility detected by a real-time SG method correlated with the grade of mucosal histology. This method is useful to detect rejection at an early stage by examining the frequency of MMC propagation. [Copyright &y& Elsevier]

: PurposeThe clinical results of small bowel transplantation (SBT) have not been satisfactory mainly because of the immunological barrier. It is important to detect the presence of and to perform adequate treatment of rejection as early as possible to improve graft survival. Therefore, we have established a pig model to monitor graft motility as a means to detect rejection in real time.: MethodsOrthotropic SBT was performed in 25 pigs using FK-506 (0.05 to 0.1 mg/kg/d) immunosuppression. The interdigestive motor patterns were evaluated using strain gauge force transducers (SG). Seven pigs without SBT were treated as controls (C). Animals that displayed migrating motor complex (MMC) activity as evidenced by duration, amplitude, and interval in the graft were alive more than 10 days with adequate oral feeding: the functional graft (FG) group. In contrast the rejection (R) group did not show these activities on data recorded within 10 days before death due to rejection.: ResultsThe FG group showed MMC propagated throughout the graft with all parameters almost the same as the control group except for the duration. In contrast, all parameters in the group R were significantly lower than those in group FG, suggesting that group R motility was obviously impaired by rejection.: ConclusionsThe SG method may afford real-time monitoring of transplanted bowel motility that could be useful to detect rejection after SBT. [Copyright &y& Elsevier]