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81.
A rare case of primary pulmonary synovial sarcoma with polypoid endobronchial growth in a 42-year-old Japanese woman is described. Left upper sleeve lobectomy was performed for the polypoid tumor measuring 2.5 cm in the left major bronchus and the patient was treated with adjuvant chemotherapy. Three years later, a recurrent tumor was discovered. Microscopically, this tumor was characterized by a proliferation of oval to spindle-shaped cells arranged in sheets and fascicles and covered by the thin normal bronchial epithelium. Immunohistochemically, tumor cells were positive for vimentin, and focally positive for pancytokeratin recognized by AE1/AE3, cytokeratin 7 and epithelial membrane antigen. A chimera gene, SYT-SSX1, was detected. Recently, primary pulmonary synovial sarcoma is an increasingly recognized clinical entity; however, most of these tumors present as a parenchymal mass. The present case is a unique example of primary synovial sarcoma of endobronchial polypoid type. This case suggests that pulmonary synovial sarcoma might originate from bronchial submucosal stromal tissue. 相似文献
82.
Watanabe T Sakamoto A Tamiya S Oda Y Masuda K Tsuneyoshi M 《International journal of molecular medicine》2000,5(6):605-608
It has been shown that the NF1 (neurofibromatosis type 1) gene encodes a tumor suppressor which inactivates ras proteins. Among malignant mesenchymal tumors, H-ras-1 mutations have been found in malignant fibrous histiocytoma, leiomyosarcoma and embryonal rhabdomyosarcoma. However, studies on H-ras-1 mutation of many cases of malignant peripheral nerve sheath tumors (MPNST) have not been documented. Therefore, we investigated H-ras-1 mutations of MPNST. In 45 cases of MPNSTs of our files, DNA was extracted from the formalin-fixed paraffin-embedded tissue, and the mutations of the H-ras-1 gene were detected by using PCR-RFLP (polymerase chain reaction- restriction fragment length polymorphisms) method and direct sequencing. We found two cases with H-ras-1 point mutation in MPNST for the first time. Both cases showed the same mutation in codon 13.1 [GGT(Gly) to AGT(Ser) transition]. Interestingly, both cases were associated with NF1. It is possibile that the mutation of the H-ras-1 gene occurred after the mutation of the NF1 gene in the MPNST. 相似文献
83.
Oda Y Funasaka K Kitano M Nakama A Yoshikura T 《Environmental and molecular mutagenesis》2004,43(1):10-19
In the present study, we developed a rapid umu-microplate test system that uses the nitroreductase- and O-acetyltransferase-overproducing Salmonella typhimurium strain NM3009 and the O-acetyltransferase-overproducing S. typhimurium strain NM2009 to detect genotoxic activity in small volume samples. The assay was used to test the genotoxicity of several standard mutagens and environmental samples. Exponentially growing cultures of NM3009, NM2009, and the parental strain TA1535/pSK1002 were incubated in 96-well microplates with test chemicals both in the presence and in the absence of rat liver S9. The relative beta-galactosidase activities were then determined colorimetrically using either chlorophenol red-beta-D-galactopyranoside (CPRG) or O-nitrophenyl-beta-D-galactopyranoside (ONPG) as a measure of umuC gene induction activity. The sensitivities of NM3009 without S9 mix and NM2009 with S9 mix to nitroarenes and aromatic amines were up to 24- to 75-fold higher than those of the parent strain. Induction of umuC gene expression was detected more readily with CPRG than ONPG. The umu-microplate assay also detected genotoxicity in organic extracts of particulate matter from air samples collected in Osaka City, Japan. The pattern of the responses suggested that the genotoxic activity of the particulate extract was due primarily to nitrated polycyclic aromatic hydrocarbons. Our results indicate that the umu-microplate assay may be a useful way of carrying out rapid screens for genotoxicity in small-volume environmental samples. 相似文献
84.
We investigated maximal isometric force and electromyographic (EMG) activity of the biceps brachii muscle during rapid bilateral (BL) and unilateral (UL) elbow flexion in 11 right-handed subjects. The BL exhibited a deficit in force for both arms and more so for the right than the left arm during the rising phase of force generation. The EMG of the left biceps brachii muscle was similar during UL and BL, but for the right arm EMG was lower during BL than during UL for the rising phase of force generation. The BL to UL ratio of mean power frequency of the EMG was lower for the right than for the left arm. The data would suggest that the relatively small BL strength was associated with a equally small EMG and a shift to a lower mean power frequency especially for the fast motor units of the dominant muscle. 相似文献
85.
Suzuki H Amizuka N Oda K Li M Yoshie H Ohshima H Noda M Maeda T 《Archives of histology and cytology》2005,68(5):371-381
Mice homozygous for klotho gene deletion are well established aging models as they mimic certain aspects of human senescence e.g. osteoporosis. Induced senescence may affect cellular functions and alter the histological properties of the extracellular matrices. The present study examined the histological and ultrastructural features of osteocytes and the surrounding bone matrix in klotho-deficient mice. As expected, osteoblasts showed a flattened shape with a weak immunoreactivity for alkaline phosphatase, and the bone matrix contained many empty osteocytic lacunae. The walls of both normal and empty lacunae were intensely immunopositive for osteopontin and dentin matrix protein-1, but featured an inconsistent immunoreactivity for osteocalcin and type I collagen. Not surprisingly, TUNEL-positivity, indicative of apoptosis, was found in many osteoblasts, osteocytes, and bone marrow cells of the klotho-deficient mice. In transmission electron microscopy, an amorphous matrix containing non-collagenous organic materials was recognizable around osteoblasts and in the osteocytic lacunae. Some osteoblasts on the bone surface featured these amorphous materials in vacuoles associated with their trans-Golgi network, indicating that, under klotho-deficient conditions, they synthesize and secrete the non-collagenous structures. Some osteocytes displayed pyknosis or degenerative traits. Thus, our findings provide histological evidence that klotho gene deletion influences the spatial distribution of osteocytes and the synthesis of bone matrix proteins in addition to the accelerated aging of bone cells. 相似文献
86.
87.
Bibek Dutta Taichi Asami Tohru Imatomi Kento Igarashi Kento Nagata Tomomi Watanabe-Asaka Takako Yasuda Shoji Oda Manfred Shartl Hiroshi Mitani 《Journal of radiation research》2021,62(1):12
Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53+/−, p53−/−) and Hd-rR HNI hybrid (p53+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53+/− fish than in p53−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids. 相似文献
88.
K Oda H Miura H Shibasaki C Endo R Kakigi Y Kuroda K Tanaka 《Journal of the neurological sciences》1990,98(2-3):139-148
By studying intramuscular nerves in 2 patients from 2 families with hereditary pressure-sensitive neuropathy (HPSN), the occurrence of abnormal thickening of myelin sheaths ("tomacula") was for the first time demonstrated in motor nerve fibers. Furthermore, the tomacula were found to line up on certain axons instead of being randomly distributed. These results indicate that the recurrent mononeuropathies of HPSN arise from an underlying asymptomatic motor and sensory polyneuropathy. It is also suggested that some signals emanating from the axons might be related to the formation of tomacula on the basis of the genetically determined myelination disorder. 相似文献
89.
K Gohji M Sugino S Arakawa O Matsumoto S Kamidono A Fujii S Morishita Y Nakano Y Oda G Hamami 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(9):1404-1411
One hundred patients with carcinoma of the urinary bladder were treated with preoperative intra-arterial anticancer drug infusion in combination with an active carbon-based artificial liver or preoperative radiotherapy (400 rad X 5 days, total 2000 rad) in order to alleviate systemic side effects after preoperative adjuvant therapy and to perform radical cystectomy as soon as possible. Five-year survival was 69.8% in the artificial liver combined preoperative intra-arterial anticancer drug infusion group, and that of the no-pretreatment group and the preoperative irradiated group was 48.6% and 45.8%, respectively. In particular, the CDDP treated group had a higher 5-year survival of 77.4% than did the without CDDP treated group. This was attributable mostly to improved prognosis of T2, whereas either of these preoperative adjuvant therapies failed to ameliorate the prognosis of T3 or T4 stage patients. Therefore, systemic preoperative anticancer chemotherapies such as M-VAC are necessary to destroy "micrometastases" and to improve the prognosis of highly advanced bladder cancer. 相似文献
90.
Summary To investigate the leavening ability of yeast in dough, chromosome loss was induced by benomyl treatment in YOY1037, a diploid between a baking strain and a laboratory strain, and its effect on the leavening ability was studied. When benomyl-treated cells were spread on plates with a dye indicator for ploidy, about 20% of the visible colonies were stained dark blue or dark purple; the rest stained pale blue, similar to the diploid YOY1037. Strains showing the MAT phenotype, and non-galactose fermenting strains, apparently having lost particular chromosomes, were observed only in those with darkcoloured colonies. Strains with dark-coloured colonies showed a wider range of leavening ability than did those with pale-coloured colonies. 相似文献