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In the wild, primate foraging behaviors are related to the diversity and nutritional properties of food, which are affected by seasonal variation. The goal of environmental enrichment is to stimulate captive animals to exhibit similar foraging behavior of their wild counterparts, e.g. To extend foraging time. We conducted a 12-month study on the foraging behavior of Japanese macaques in a semi-naturally forested enclosure to understand how they use both provisioned foods and naturally available plant foods and what are the nutritional criteria of their consumption of natural plants. We recorded time spent feeding on provisioned and natural plant foods and collected the plant parts ingested of their major plant food species monthly, when available.We conducted nutritional analysis (crude protein, crude lipid, neutral detergent fiber-'NDF', ash) and calculated total non-slructural carbohydrate - 'TNC' and total energy of those food items. Monkeys spent 47% of their feeding time foraging on natural plant species. The consumption of plant parts varied significantly across seasons. We found that leaf items were consumed in months when crude protein, crude protein-to-NDF ratio, TNC and total energy were significantly higher and NDF was significantly lower, fruit/nut items in months when crude protein and TNC were significantly higher and crude lipid content was significantly lower, and bark items in months when TNC and total energy were higher and crude lipid content was lower. This preliminary investigation showed that the forested enclosure allowed troop members to more fully express their species typical flexible behavior by challenging them to adjust their foraging behavior to seasonal changes of plant item diversity and nutritional content, also providing the possibility for individuals to nutritionally enhance their diet.  相似文献   
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Using a class-I-restricted T cell receptor (TCR) transgenic mice (Tgm), 2C (Valpha3.1/Vbeta 8.2, specific for L(d) + LSPFPFDL), the development and cytokine production of tg-TCR(+) NKT cells were analyzed. We found that CD8(+) or double negative (DN) NKT cells constituted a major population of NKT cells in the H-2(b/b) 2C Tgm (positive selecting background) or the H-2(b/d) 2C Tgm (negative selecting background), respectively. Virtually no NKT cells were generated in the H-2(k/k) 2C Tgm (neutral selecting background). CD8(+) NKT cells in the H-2(b/b) 2C Tgm expressed CD8alphabeta heterodimers, whereas those in the H-2(b/d) 2C Tgm expressed CD8alphaalpha homodimers. These findings suggest that development of a subpopulation of NKT cells is influenced by the H-2 molecules. Upon stimulation with anti-CD3 mAb, tg-TCR(+) NKT cells generated in the H-2(b/b) and H-2(b/d) backgrounds produced IFN-gamma, but not IL-4.  相似文献   
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In this paper the development and feasibility of a novel detection system for a low molecular weight chemical, in which a peptide was utilized as a binding molecule, are described. Surface plasmon resonance (SPR) apparatus was used as a transducer. The porphyrin binding peptide, PSP2, was used as a model peptide ligand, while a porphyrin derivative, H2TMpyP, was used as a model low-molecular-weight chemical. PSP2 was covalently immobilized onto the SPR sensor chip and SPR measurement using the PSP2-immobilized chip for various concentrations of porphyrin was carried out. H2TMpyP was detectable in the range from 100 ng ml−1 to 10 μg ml−1 with a linear correlation and good precision and the PSP2-immobilized chip could be regenerated within 1 min after measurement in this system. From comparison of the detection manners of three porphyrin derivatives, the ability of a short peptide to discriminate between differences in molecular structure was demonstrated. Moreover, the self-assembled monolayer (SAM) of PSP2 was successfully prepared on the gold substrate and H2TMpyP could be detected using the PSP2-SAM chip.  相似文献   
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Neuroblastoma, which is a malignant tumor consisting of dedifferentiated neuroectodermal cells, is known to show spontaneous maturation or regression in its growth. Cultured human neuroblastoma GOTO cells could be induced to differentiate into Schwannian cells and neuronal cells by incubation in the presence of 5-bromo-2'-deoxyuridine (BrdU) and by serum depletion, respectively. Here we report that in association with these differentiations, cells differentiated into Schwannian cells specifically expressed a cell adhesion molecule CD44, of which expression is usually suppressed in GOTO cells. In contrast, it remained suppressed in cells differentiated into neuronal cells. Polymerase-chain reaction revealed that the CD44 species expressed was the hemopoietic form (CD44H) with long cytoplasmic tail. Furthermore, the newly expressed CD44 in the cells was found exclusively in membrane microdomains, called lipid rafts. These data suggest that CD44 might play an important role in GOTO cells differentiated into Schwannian cells.  相似文献   
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The purposes of this study are to construct a simple dioxin detection system using peptides that bind to dioxin, and to test the system on real environmental samples. In this method, dioxin and N-NBD-3-(3',4'-dichlorophenoxy)-1-propylamine (NBD-DCPPA) are competitively bound to the peptides synthesized on beads. The fluorescence intensity of the bead decreases with increasing dioxin concentration. The concentration of dioxin is determined by measuring the fluorescence intensity using a fluorescence microscope equipped with a CCD camera. The fluorescence microscope system was equipped with a motor-driven stage and could be used with 96-well microplates and analytical software that automatically measured the fluorescence intensity of the bead images in the wells. Dioxin detection conditions, reaction temperature, number of beads and concentration of the organic solvent were optimized. About 0.5 nM (150 pg mL(-1)) of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TeCDD) could be detected under the optimized conditions. Environmental soil samples were subjected to the detection system using the peptide beads. Although the results obtained correlated poorly with the toxicity equivalency quantity (TEQ) concentration obtained by a GC/MS method, our method is robust enough as a prescreening method to detect at least 250 pg-TEQ g(-1), the survey level for soil as stipulated in the law concerning special measures against dioxins in Japan.  相似文献   
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Some tumor cells induce platelet aggregation in the bloodstream, which has been implicated in tumor metastasis. In this study, we investigated the mechanism of platelet aggregation induced by a human neuroblastoma cell line, GOTO. It was revealed that GOTO cells had tissue factor on their surface and converted factor X (FX) to FXa with the aid of factor VIIa. The produced FXa formed prothrombinase complex on the cells and activated prothrombin. From experiments on activity inhibition by specific monoclonal as well as polyclonal antibodies, it was concluded that factor V did not constitute this prothrombinase complex. Another cofactor known to constitute prothrombinase complex on some cells, effector cell protease receptor-1 (EPR-1), was not expressed on GOTO cells, suggesting that the cofactor composing FXa-dependent prothrombinase activity on GOTO cells is not factor V or EPR-1 but, rather, is an unknown molecule. Upon the culturing in the presence of 5-bromo-2′-deoxyuridine for 4 days, GOTO cells differentiated into Schwann-like cells, and both FXase and prothrombinase activities were greatly diminished. Flow cytometric analyses revealed that the decrease of FXase activity should be attributed to the decrease of tissue factor expression on GOTO cells. Because these activities greatly diminished upon cellular differentiation, the expression of both cofactor molecules may be related to the malignant and metastatic nature of the tumor cells. J. Cell. Physiol. 173:406–414, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
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Thecharacteristics of L-lactic acid transport across thetrophoblast basal membrane were investigated and compared with those across the brush-border membrane by using membrane vesicles isolated from human placenta. The uptake ofL-[14C]lactic acid into basal membranevesicles was Na+ independent, and an uphill transport wasobserved in the presence of a pH gradient([H+]out > [H+]in).L-[14C]lactic acid uptake exhibitedsaturation kinetics with a Km value of 5.89 ± 0.68 mM in the presence of a pH gradient.p-Chloromercuribenzenesulfonate and-cyano-4-hydroxycinnamate inhibited the initial uptake, whereas phloretin or 4,4'-diisothiocyanostilbene-2,2'-disulfonate did not.Mono- and dicarboxylic acids suppressed the initial uptake. Inconclusion, L-lactic acid transport in the basal membraneis H+ dependent and Na+ independent, as is alsothe case for the brush-border membrane transport, and itscharacteristics resemble those of monocarboxylic acid transporters.However, there were several differences in the effects of inhibitorsbetween basal and brush-border membrane vesicles, suggesting that thetransporter(s) involved in L-lactic acid transport in thebasal membrane of placental trophoblast may differ from those in thebrush-border membrane.

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Activation of APC via CD40-CD40 ligand pathway induces up-regulation of costimulatory molecules such as B7 and production of IL-12. Interaction between B7 on APC and CD28 on naive T cells is necessary for priming the T cells. On the other hand, interaction between B7 on APC and CTLA-4 on activated T cells transduces a negative regulatory signal to the activated T cells. In the present study, we attempted to generate tumor-specific CTL by s.c. administration of antigenic peptides encapsulated in multilamellar liposomes (liposomal peptide vaccine) with anti-CD40 mAb and/or anti-CTLA-4 mAb. Liposomal OVA257-264 and anti-CD40 mAb or anti-CTLA-4 mAb were administrated to C57BL/6 mice and the splenocytes were cocultured with OVA257-264 for 4 days. The splenic CD8+ T cells showed a significant cytotoxicity against EL4 cells transfected with cDNA of OVA. In addition, administration of both anti-CD40 and anti-CTLA-4 mAb enhanced the CTL responses. Considerable CTL responses were induced in MHC class II deficient mice by the same procedure. This finding indicated that CTL responses could be generated even in the absence of Th cells. When BALB/c mice were immunized with pRL1a peptide that are tumor-associated Ag of RLmale symbol1 leukemia cells using the same procedure, significant CTL responses were induced and prolonged survival of the BALB/c mice was observed following RLmale symbol1 inoculation. These results demonstrate that anti-CD40 mAb and anti-CTLA-4 mAb function as immunomodulators and may be applicable to specific cancer immunotherapy with antitumor peptide vaccine.  相似文献   
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Hand preference of wild moor monkeys Macaca maurus was investigated in food reaching situations at the Karaenta Nature Reserve, South Sulawesi, Indonesia. The frequency picking up sweet-corn grains to take into the mouth by either hand of monkeys was counted directly at the feeding ground where sweet-corn grains were scattered for monkeys. Among the 20 monkeys examined, 8 were fight-handed, 8 were left-handed, and 4 were ambilateral. The results indicated the prevailed hand preference on individual level but not either trends of left- or right-hand preference on population level. The trend toward a higher proportion of left-handed monkeys found in Japanese and rhesus monkeys was not found. Some other characteristics found in moor monkeys are discussed in comparison with those previous findings in Japanese and Tibetan macaques in order to evaluate variations within the genus Macaca.  相似文献   
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