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81.
Kazuki Oka Naotoshi Yoshiyama Koji Tojo Ryuichiro Machida Masatsugu Hatakeyama 《Development genes and evolution》2010,220(1-2):53-59
Larvae of the sawfly, Athalia rosae, have remarkable abdominal prolegs. We analyzed the morphogenesis of appendages and the expression of decapentaplegic and Distal-less genes during embryonic development to characterize the origin of prolegs. Proleg primordia in abdominal segments A1–A9 appeared shortly after the inner lobes (endites) of gnathal appendages were formed. These were located on the ventral plates, medioventral to the appendages of the other segments in light of serial homology. Nothing was seen where the main axis of the appendage should develop in abdominal segments. The primordia in A1 and A9 disappeared before larval hatching. Anal prolegs appeared separate from cerci, the main axes of appendages, which were formed temporarily in A11. The expression of decapentaplegic, which reflects the primary determination of appendages, was detected in the lateral juxtaposition with the prolegs. Distal-less was expressed in the main axes of appendages, protruding endites and the cerci, but not in prolegs and anal prolegs or the gnathal endites which do not protrude. These findings suggest a possibility that the abdominal and anal prolegs of A. rosae are outgrowths of ventral plates which derived from coxopodal elements, but not main axes of appendages. 相似文献
82.
Nobuyuki Yamasaki Tomomitsu Hatakeyama Hideki Ohba Gunki Funatsu 《Bioscience, biotechnology, and biochemistry》2013,77(8):2227-2232
Chemical modification of tryptophan residues in ricin E was investigated with regard to saccharide-binding. Two out of ten tryptophan residues in ricin E were modified with N- bromosuccinimide at pH 4.5 in the absence of specific saccharide accompanied by a marked decrease in the cytoagglutinating activity. Such a loss of the cytoagglutinating activity was found to be principally due to the oxidation of one tryptophan residue per B-chain. In the presence of lactose, one tryptophan residue/mol was protected from the modification with retention of a fairly high cytoagglutinating activity. However, G a IN Ac did not show such a protective effect. The binding of lactose to ricin E altered the environment of the tryptophan residue at the low affinity binding site of ricin E, leading to a blue shift of the fluorescence spectrum and an UV-difference spectrum with a maximum at 290 nm and a trough at 300 nm. The ability to generate such spectroscopic changes induced by lactose was retained in the derivative in which one tryptophan residue/mol was oxidized in the presence of lactose, but not in the derivative in which two tryptophan residues/mol were oxidized in the absence of lactose. Based on these results, it is suggested that one of the two surface-localized tryptophan residues is responsible for saccharide binding at the low affinity binding site of ricin E, which can bind lactose but lacks the ability to bind GalNAc. 相似文献
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85.
Suzuki H Ikeda N Kobayashi K Terashima Y Shimada Y Suzuki T Hagiwara T Hatakeyama S Nagaoka K Yoshida J Saito Y Tanaka J Hayashi M 《Mutation research》2005,583(2):133-145
We conducted simultaneous liver and peripheral blood micronucleus assays in young rats with seven rodent hepatocarcinogens-4,4'-methylenedianiline (MDA), quinoline, o-toluidine, 4-chloro-o-phenylenediamine (CPDA), dimethylnitrosamine (DMN), p-dimethylaminoazobenzene (DAB), and di(2-ethylhexyl)phthalate (DEHP)-and two mutagenic chemicals-kojic acid and methylmethanesulfonate (MMS). Quinoline, DMN, and DAB were positive in the liver assay, while o-toluidine, kojic acid, DAB, and MMS were positive in the peripheral blood assay. o-Toluidine, kojic acid, and DAB are reportedly negative in mouse bone marrow micronucleus assays, indicating a species difference. Our results revealed a correlation between micronucleus induction in hepatocytes and hepatocarcinogenicity. This technique can be useful for the detection of micronucleus-inducing chemicals that require metabolic activation, and it enables simultaneous comparison of the micronucleus-inducing potential of chemicals in the liver and peripheral blood in the same individual. 相似文献
86.
Harada H Morozumi K Nashihara H Hatakeyama E 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2005,24(4):383-388
This paper investigates the applicability of cerebral blood flow in evaluating the technological adaptability for operating industrial products. The procedure of the experiment was explained to the subjects and informed consent was obtained from them. Twenty male and twenty female subjects (19-22 yrs) operated the destination setting task of a car navigation system. Subjects were divided into two sub groups to operate tasks of model A and model B of a car navigation system. Operation time of tasks and cerebral blood flow of frontal region were measured during tasks. Non-invasive measuring of regional cerebral blood flow was estimated by measuring deoxygenated hemoglobin, oxygenated hemoglobin, and total haemoglobin using the time resolved spectroscopy (TRS). Females were faster than males in operating the task of setting the destination searched by street address. Total haemoglobin of male subjects was significantly higher than that of females during resting and tasks. Changes of cerebral blood flow were observed during operating a car navigation system. In this paper we discussed the possibility of physiological evaluation for technological adaptability by means of the performance and brain hemodynamics measurement. 相似文献
87.
Yajima K Shirai Y Fujita N Sato D Umezu H Hatakeyama K 《World journal of surgical oncology》2005,3(1):14-3
BACKGROUND: Subcutaneous leiomyosarcoma is a rare condition that accounts for 1% to 2% of all superficial soft tissue malignancies. Approximately 10% of cases arise in the trunk, although the extremities are the most commonly affected. CASE PRESENTATION: We report herein the case of a 31-year-old man with a subcutaneous leiomyosarcoma, measuring 124 x 105 mm, arising in the left inguinal region. A wide local excision (with a resection margin >/= 20 mm) was performed. Histological examination of the resected specimen revealed a leiomyosarcoma with high cellularity and two mitoses per 10 high-power fields. The patient remains well with no evidence of disease 5 years and 8 months after the operation. CONCLUSION: This is the first reported case of subcutaneous leiomyosarcoma arising in the inguinal region and also one of the largest tumors reported. The experience of this case and a review of the English-language literature (PubMed, National Library of Medicine, Bethesda, MD, USA) suggest that a resection margin of >/= 10 mm is recommended when excising this rare tumor. 相似文献
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89.
Sato Y Yokoyama A Shibata K Akimoto Y Ogino S Nodasaka Y Kohgo T Tamura K Akasaka T Uo M Motomiya K Jeyadevan B Ishiguro M Hatakeyama R Watari F Tohji K 《Molecular bioSystems》2005,1(2):176-182
Carbon nanotubes (CNTs) are single- or multi-cylindrical graphene structures that possess diameters of a few nanometers, while the length can be up to a few micrometers. These could have unusual toxicological properties, in that they share intermediate morphological characteristics of both fibers and nanoparticles. To date, no detailed study has been carried out to determine the effect of length on CNT cytotoxicity. In this paper, we investigated the activation of the human acute monocytic leukemia cell line THP-1 in vitro and the response in subcutaneous tissue in vivo to CNTs of different lengths. We used 220 nm and 825 nm-long CNT samples for testing, referred to as "220-CNTs" and "825-CNTs", respectively. 220-CNTs and 825-CNTs induced human monocytes in vitro, although the activity was significantly lower than that of microbial lipopeptide and lipopolysaccharide, and no activity appeared following variation in the length of CNTs. On the other hand, the degree of inflammatory response in subcutaneous tissue in rats around the 220-CNTs was slight in comparison with that around the 825-CNTs. These results indicated that the degree of inflammation around 825-CNTs was stronger than that around 220-CNTs since macrophages could envelop 220-CNTs more readily than 825-CNTs. However, no severe inflammatory response such as necrosis, degeneration or neutrophil infiltration in vivo was observed around both CNTs examined throughout the experimental period. 相似文献
90.
Kuramoto T Uzuyama H Hatakeyama T Tamura T Nakashima T Yamaguchi K Oda T 《Journal of biochemistry》2005,137(1):41-50
We found that CEL-I was a potent cytotoxic lectin. MDCK, HeLa, and XC cells were highly sensitive to CEL-I cytotoxicity and killed in a dose-dependent manner, whereas CHO, L929, and RAW264.7 cells were relatively resistant to CEL-I, and no significant toxicity was observed up to 10 microg/ml. Among these cell lines, MDCK cells showed the highest susceptibility to CEL-I cytotoxicity. A binding study using FITC-labeled CEL-I (F-CEL-I) revealed that the amounts of bound F-CEL-I on the sensitive cell lines were evidently greater than those on the resistant cell lines, suggesting that the different susceptibility of the cell lines to CEL-I cytotoxicity is partly explained by different efficiencies of binding of CEL-I to these cell lines. Interestingly, the cytotoxicity of CEL-I toward MDCK cells was more potent than those of other lectins such as WGA, PHA-L, and Con A, even though these lectins were capable of binding to MDCK cells at comparable levels to CEL-I. Since the cytotoxicity of CEL-I was strongly inhibited by GalNAc, the binding to cell surface specific carbohydrates is essential for the CEL-I cytotoxicity. The trypan blue dye exclusion test indicated that CEL-I caused a disorder of plasma membrane integrity as a relatively early event. CEL-I failed to induce the release of carboxyfluorescein (CF) from CF-loaded MDCK cells as seen for pore-forming hemolytic isolectin CEL-III, suggesting that the primary cellular target of CEL-I may be the plasma membrane, but its action mechanism differs from that of CEL-III. Although CEL-I induced dramatic cellular morphological changes in MDCK cells, neither typical apoptotic nuclear morphological changes nor DNA fragmentation was observed in CEL-I-treated MDCK cells even after such cellular changes. Our results demonstrated that CEL-I showed a potent cytotoxic effect, especially on MDCK cells, by causing plasma membrane disorder without induction of apoptosis. 相似文献