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101.
Akihiro Hirata Yoko Miyamoto Akihisa Kaneko Hiroki Sakai Kyoko Yoshizaki Tokuma Yanai Takako Miyabe‐Nishiwaki Juri Suzuki 《Journal of medical primatology》2019,48(2):137-140
Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non‐human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques. 相似文献
102.
Jianlin Han Marion Jean Christian Roussel Hiroki Moriwaki Vadim A. Soloshonok 《Chirality》2019,31(4):328-335
Herein, we disclose the design of a model Ni(II) complex of glycine Schiff base possessing single‐nitrogen stereogenic center, which was successfully used for high‐performance liquid chromatography (HPLC)‐assisted assessment of its configurational stability. The major finding is that the configurational stability of the Ni(II)‐coordinated nitrogen is profoundly dependent on the reaction conditions used, in particular the solvent, and can range from inconsequential (t½ less than 5 min) to virtually completely stable (t½ 90 y). The discovery reported in this study most likely to be of certain theoretical and synthetic value. 相似文献
103.
Hashimoto T Ashida H Sano T Furuyashiki T Hatanaka Y Minato K Mizuno M Nomura K Kumatori A Kanazawa K Danno G 《Biochimica et biophysica acta》2001,1539(1-2):44-57
3-Amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), one of the tryptophan pyrolysates, is a dietary carcinogen and is formed in cooked meat and fish in our daily diet. Trp-P-1 will affect the cells in the blood circulation system before it causes carcinogenicity in target organs such as the liver. In this study, the cytotoxicity of Trp-P-1 was investigated in mononuclear cells (MNCs) from blood. Trp-P-1 (10-15 microM) decreased cell viability and induced apoptosis characterized both by morphological changes and by DNA fragmentation 4 h after treatment. DNA fragmentation was also observed following treatment at 1 nM after 24 h in culture. This result suggested that apoptosis would occur in the body following unexpected intake of foods containing Trp-P-1. To determine the mechanism of apoptosis, we investigated the activation of the caspase cascade in MNCs. Trp-P-1 (10-15 microM) activated the caspase cascade, i.e. the activity of caspase-3, -6, -7, -8 and -9 increased dose-dependently using peptide substrates, the active forms of caspase-3, -8 and -9 were detected by immunoblotting, and cleavage of poly(ADP-ribose) polymerase and protein kinase C-delta as the intracellular substrates for caspases was observed. A peptide inhibitor of caspase-8 completely suppressed activation of all other caspases, while an inhibitor of caspase-9 did not. These results indicated that caspase-8 may act as an apical caspase in the Trp-P-1-activated cascade. 相似文献
104.
In this paper we investigate population dynamics, genealogy and complexity-increase of locally interacting populations of cellular automata-based evolving self-replicating loops (evoloops). We outline experiments indicating that the evolutionary growth in complexity, known to be achievable in principle given the complete genetic accessibility granted by universal construction, may be achievable in practice using much simpler replicating structures. By introducing evoloop populations to hostile environments, we demonstrate that selection pressures toward smaller species can be mediated to enable evolutionary accessibility to larger species, which themselves roam a much more vast portion of genetic state-space. We show that this growth in size results from intrinsically biased genealogy inherent in the rules of the evoloop CA, normally suppressed by selection pressures from direct competition favouring the smallest species. This shows that, in populations of simple self-replicating structures, a limited form of complexity-increase may result from a process which is driven by biased genealogical connectivity--a purely emergent property arising out of bottom-up evolutionary dynamics--and not just by adaptation . Implications of this result are discussed and contrasted with other self-replication studies in Artificial Life and Biology. 相似文献
105.
Matsuda K Tsunoda T Tanaka H Umano Y Tanimura H Nukaya I Takesako K Yamaue H 《Cancer immunology, immunotherapy : CII》2004,53(7):609-616
Carcinoembryonic antigen (CEA) is strongly expressed in a vast majority of gastrointestinal carcinomas. Recently, epitope peptides of CEA were identified. We have demonstrated HLA-A24–restricted peptide, CEA652[9] (TYACFVSNL), was capable of eliciting specific cytotoxic T lymphocytes (CTLs) which could lyse tumor cells expressing HLA-A24 and CEA. HLA-A24 is the most applicable MHC class I allele in the Japanese population. In this pilot study, we have used the peptide-pulsed dendritic cells (DCs) generated from peripheral blood mononuclear cells (PBMCs) supplemented with GM-CSF and IL-4 as the source of the vaccine. Eight patients with advanced CEA-expressing gastrointestinal malignancies received subcutaneous injections every 2 or 3 weeks. Immunomonitoring was performed by ELISpot (enzyme-linked immunosorbent spot) assay to measure the precursor frequency of CTLs and their capacity to elicit antitumor CTLs in vitro. Four of seven patients have developed their CTL response after vaccinations. DTH reaction was observed in one of eight patients at the DC-injected site. Skin biopsy at the injected site showed the infiltration of the lymphocytes. Furthermore, A24/CEA peptide tetramer assay revealed an increase in peptide-specific T-cell precursor frequency in vaccinated patients. No significant toxic adverse effects were observed, except for mild diarrhea in one case after three vaccinations. Three patients have shown stabilization of the disease after vaccinations. In conclusion, our results clearly demonstrated that our vaccination protocol was safe and might develop a CEA-specific CTL response in cancer patients. 相似文献
106.
Nagahata H Higuchi H Teraoka H Takahashi K Takahashi K Kuwabara M Inanami O Kuwabara M 《Immunology and cell biology》2004,82(1):32-37
Stimulant-induced viability of neutrophils, nuclear-fragmentation, increase in intracellular calcium ([Ca2+]i), expression of annexin V on neutrophils and proteolysis of a fluorogenic peptide substrate Ac-DEVD-MCA (acetyl Asp-Glu-Val-Asp alpha-[4-methyl-coumaryl-7-amide]) by neutrophil lysates from five normal calves and three calves with leucocyte adhesion deficiency were determined to evaluate the apoptosis of normal and CD18-deficient neutrophils. Viability was markedly decreased in control neutrophils stimulated with opsonized zymosan (OPZ), compared to CD18-deficient neutrophils at 37 degrees C after incubation periods of 6 and 24 hours. The rate of apoptosis of control neutrophils stimulated with OPZ increased significantly depending on the incubation time, whereas no apparent increase in apoptosis was found in CD18-deficient neutrophils under the same conditions. Aggregated bovine (Agg) IgG-induced apoptosis of control neutrophils was not significantly different from that of CD18-deficient neutrophils. The expression of annexin V on OPZ-stimulated control neutrophils was greater than that of unstimulated ones 6 h after stimulation. No apparent increase in annexin V expression on CD18-deficient neutrophils was found with OPZ stimulation. A delay in apoptosis was demonstrated in CD18-deficient bovine neutrophils and this appeared to be closely associated with lowered signalling via [Ca2+]i, diminished annexin V expression on the cell surface, and decreased caspase 3 activity in lysates. 相似文献
107.
A survey of soils and trees was conducted on Syunkunitai coastal sand dune in eastern Hokkaido to clarify the relationships between the soil properties and the plant cover type. A belt transect of 360m in length was established across the dune. Three community types, that is, a Picea glehnii forest, an Abies sachalinensis forest, and a salt marsh were recognized. Soil types at the study area were determined to be sandy immature soil and peat soil. Their horizon sequences were described as A0–V–C or T–V–C layers (A0, T, V, and C indicate layers of leaf litter, peat, volcanic deposit, and parent material, respectively). The Abies sachalinensis forest was characterized by a relatively high calcium concentration in the surface soil layer and a tendency for podzolization in the volcanic deposit layer. The Picea glehnii forest was characterized by peat accumulation because of the high ground water table, volcanic deposits in the soil profile, and the strong influence of sea salt on the soil chemistry. The roots in the Picea glehnii forest were distributed more shallowly than those in the Abies sachalinensis forest, thus avoiding the high water table level as well as the influence of seawater in the soil. The salt marsh showed an extremely high sodium concentration and base saturation, indicating that this area was directly affected by seawater. Recently, the periphery of the Picea glehnii forest on Syunkunitai sand dune has been declining because of seawater inundation caused by ground subsidence. 相似文献
108.
Hashimoto T Sano T Ito W Kanazawa K Danno G Ashida H 《Bioscience, biotechnology, and biochemistry》2004,68(4):964-967
A dietary carcinogen, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) at 20 microM activates caspase-3-like proteases as an apoptotic marker in rat splenocytes. The present study demonstrated 100 microM Trp-P-1 induced necrosis with activation of caspase-3-like proteases. The activation in necrosis and apoptosis resulted from the activation of caspase-9 and caspase-8, respectively. Thus, Trp-P-1 induces apoptosis and necrosis with the activation of different caspases. 相似文献
109.
Tsuruta H Tamura J Yamagata H Aizono Y 《Bioscience, biotechnology, and biochemistry》2004,68(2):440-443
Protein-tyrosine phosphatase [EC 3.1.3.48] from a psychrophile, Shewanella sp. shows high activity at low temperatures and has the conserved amino acid sequence of protein-Ser/Thr-phosphatases. Site-directed mutagenesis with the conserved amino acid residues indicated that His148 could be important as a general acid catalyst and Asp115 assists the protonation with His148 of the leaving group of a substrate, and that Asp76 and Asp112 were involved in binding to magnesium ions. 相似文献
110.
Elmasri H Winkler C Liedtke D Sasado T Morinaga C Suwa H Niwa K Henrich T Hirose Y Yasuoka A Yoda H Watanabe T Deguchi T Iwanami N Kunimatsu S Osakada M Loosli F Quiring R Carl M Grabher C Winkler S Del Bene F Wittbrodt J Abe K Takahama Y Takahashi K Katada T Nishina H Kondoh H Furutani-Seiki M 《Mechanisms of development》2004,121(7-8):659-671
The metameric structure of the vertebrate trunk is generated by repeated formation of somites from the unsegmented presomitic mesoderm (PSM). We report the initial characterization of nine different mutants affecting segmentation that were isolated in a large-scale mutagenesis screen in Medaka (Oryzias latipes). Four mutants were identified that show a complete or partial absence of somites or somite boundaries. In addition, five mutations were found that cause fused somites or somites with irregular sizes and shapes. In situ hybridization analysis using specific markers involved in the segmentation clock and antero-posterior (A-P) polarity of somites revealed that the nine mutants can be compiled into two groups. In group 1, mutants exhibit defects in tailbud formation and PSM prepatterning, whereas A-P identity in the somites is defective in group 2 mutants. Three mutants (planlos, pll; schnelles ende, sne; samidare, sam) have characteristic phenotypes that are similar to those in zebrafish mutants affected in the Delta/Notch signaling pathway. The majority of mutants, however, exhibit somitic phenotypes distinct from those found in zebrafish, such as individually fused somites and irregular somite sizes. Thus, these Medaka mutants can be expected to provide clues to uncovering novel components essential for somitogenesis. 相似文献