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91.
Akio Horie Katsumi Hiraoka Osamu Yamamoto Joji Haratake Takehiko Tsuchiya Hidekatsu Sugimoto 《Pathology international》1990,40(1):57-62
A case of peritoneal maligant mesothelioma in a radiation technologist, who had worked in this field for 34 years, is reported. Histopathologically, a biopsy specimen from the retroperitoneal tumor revealed a biphasic type of malignant mesothelioma. Electron microscopy disclosed that the tumor cells contained prominent microvilli, basal laminae adjacent to the stroma, junctional complexes, desmosomes, tonofilaments, clusters of glycogen granules, welt developed rough endoplasmic reticulum (RER), confronting cisternae showing direct continuity with the RER and membrane-bound granules suggestive of secretory activity. No increased amount of asbestos was detected in autopsied lung material or the peritoneal mesothelioma. The estimated cumulative dose of occupational irradiation was calculated to be about 40 to 50 rad at most. Irradiation was discussed in relation to the etiology of the peritoneal mosothelioma. Acta Pathol Jpn 40: 57–62, 1990. 相似文献
92.
Kazuo Mishima Takuma Tozawa Kohtoku Satoh Hidetomo Saitoh Yumiko Mishima 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2005,(1):101-104
Sleep timing is influenced by the circadian system. Morningness-eveningness (ME) preference in humans is affected by the free-running period, which is determined by circadian clock-relevant genes. In this study, we investigated association between the 3111T/C polymorphism in the 3'-flanking region of hClock (Homo sapiens Clock homolog) and ME preference in 421 Japanese subjects. The Horne-Ostberg ME questionnaire (MEQ) scores showed normal distribution, with mean score of 51.2 +/- 1.4 (range, 25-73), and scores were positively correlated with sleep onset time (r = 0.541, P < 0.001) and wake time (r = 0.513, P < 0.001). MEQ scores were significantly lower in subjects with 3111C/C (n = 12) than in subjects with 3111T/C (n = 106, P < 0.001) or 3111T/T (n = 303, P < 0.001), suggesting a stronger eveningness preference in 3111C/C homozygotes. This group also showed significantly delayed sleep onset (P < 0.001), shorter sleep time (P < 0.001), and greater daytime sleepiness (P < 0.001) in comparison to parameters in the subjects with the 3111T allele. There was no significant difference in any of these parameters between the 3111C/T and 3111T/T genotypes. The influence of the 3111T/C polymorphism on ME preferences in Caucasian populations remains controversial. The present findings in a Japanese population sample, which should have a relatively low risk of population stratification effects, suggest the significance of the association of the 3111C/C allele of hClock with evening preference. 相似文献
93.
Kobayashi M Hirano A Kumano T Xiang SL Mihara K Haseda Y Matsui O Shimizu H Yamamoto K 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(4):291-303
The Rad17-replication factor C (Rad17-RFC) and Rad9-Rad1-Hus1 complexes are thought to function in the early phase of cell-cycle checkpoint control as sensors for genome damage and genome replication errors. However, genetic analysis of the functions of these complexes in vertebrates is complicated by the lethality of these gene disruptions in embryonic mouse cells. We disrupted the Rad17 and Rad9 loci by gene targeting in the chicken B lymphocyte line DT40. Rad17-/- and Rad9-/- DT40 cells are viable, and are highly sensitive to UV irradiation, alkylating agents, and DNA replication inhibitors, such as hydroxyurea. We further found that Rad17-/- and Rad9-/- but not ATM-/- cells are defective in S-phase DNA damage checkpoint controls and in the cellular response to stalled DNA replication. These results indicate a critical role for chicken Rad17 and Rad9 in the cellular response to stalled DNA replication and DNA damage. 相似文献
94.
Fujita K Shimazaki N Ohta Y Kubota T Ibe S Toji S Tamai K Fujisaki S Hayano T Koiwai O 《Genes to cells : devoted to molecular & cellular mechanisms》2003,8(6):559-571
BACKGROUND: Terminal deoxynucleotidyltransferase (TdT) is a DNA polymerase that enhances the Ig and TcR gene diversity in the N region at the junctions of variable (V), diversity (D) and joining (J) segments in B- and T-cells. TdT synthesizes the N region in concert with many proteins including DNA-PKcs, Ku70 and Ku86. To elucidate the molecular mechanism of the N region synthesis, we first attempted to isolate the genes with products that directly interact with TdT. RESULTS: Using a yeast two-hybrid system, we isolated a cDNA clone encoding a novel nuclear protein that interacts with TdT. This protein was designated as TdT interacting factor 2 (TdIF2). The confined region of the C-terminal in TdIF2 is involved in specific interaction with the entire C-terminal in TdT. TdIF2 contains an acidic region comprised of 42 residues. TdIF2 was shown to bind specifically to a core histone by pull down assay using specific antibodies against TdIF2. When a TdT/TdIF2 complex was applied on to a DNA-cellulose column, only TdT bound to the column while TdIF2 passed through. TdIF2 reduces the TdT activity to 46% of its maximum value in vitro assay system using activated DNA as primer. CONCLUSIONS: TdIF2 binds directly to TdT and core histone. Furthermore, TdT, TdIF2 and core histone form a ternary complex. TdIF2 liberates H2A/H2B from a core histone in correlation with PCNA. The enzymatic consequence of the TdIF2/TdT complex is the reduction of TdT activity in vitro. TdIF2 would function as a chromatin remodeling protein at the N region synthesis. 相似文献
95.
96.
Saiki O Uda H Nishimoto N Miwa T Mima T Ogawara T Azuma N Katada Y Sawaki J Tsutsui H Matsui K Maeda A Nakanishi K 《Clinical immunology (Orlando, Fla.)》2004,112(1):120-125
Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile. 相似文献
97.
Su M Tokairin T Nishikawa Y Yoshioka T Takahashi O Watanabe H Doi Y Omori Y Yoshioka T Sageshima M Tanaka T Enomoto K 《Pathology international》2002,52(2):158-163
A rare case of rapidly growing osteosarcoma that developed in the uterine corpus of a 62-year-old woman is presented. The tumor occupied almost the entire pelvic cavity and extended into the abdominal cavity, with marked involvement of the intestines. Histopathologically, the tumor was composed of an osteoblastic component, accompanied by conspicuous bone formation, and a fibroblastic component. The tumor cells were positive for vimentin and osteocalcin, as well as desmin, alpha-smooth muscle actin and muscle-specific actin, but negative for h-caldesmon. The results indicated myofibroblastic differentiation in a part of the tumor. A review of 14 reported cases and our case of uterine osteosarcoma revealed that this tumor has a biologically aggressive nature, although its histopathological and immunohistochemical features are similar to those of osteosarcomas in soft tissue and bone. As the prognosis of patients with this tumor is poor, it is of importance to differentiate this tumor from other types of tumors arising from the uterine corpus. 相似文献
98.
Tatsuo Ushiki Osamu Ohtani Kazuhiro Abe 《Anatomical record (Hoboken, N.J. : 2007)》1995,241(1):113-122
Background: The reticular framework in the lymph node has in the past been studied mainly by light microscopy of silver-impregnated specimens. The aim of the present study is to understand three-dimensionally the ultrastructure and organization of the reticular framework better than before. Methods: The mesenteric lymph nodes of the rat were prepared either an alkali-water maceration method or a conventional method and were observed in a scanning electron microscope (SEM). Results: The SEM study of alkali-water macerated tissues visualized directly the reticular fiber network in the lymph node. The reticular fibers consisted of thin bundles of collagem fibrils. They were continuous with the collagen fibriliar sheaths of blood vessels and lymphatic sinuses as well as with the fibrous capusule, thus acting as a skeleton of the lymph node. The arrangement of the reticulum was variable, depending on individual compartments. The SEM study of conventionally treated tissues, on the other hand, clarified the shape of reticular cells and their relationship with the reticular fibers. The sinus reticular cells connected with the sinus lining cells but separated from the parenchymal reticular cells, indicating that the former two originate from lymphatic endothelial cells. The parenchymal reticular cells varied in shape depending on their locations but essentially shared features with fibroblasts. Conclusions: The arrangements of the reticular fibers in the parenchyma were closely related to the associated reticular cells, showing the possibility that the reticular cells maintain the shape of the reticular framework suitable for each compartment of the lymph node. © 1995 Wiley-Liss, Inc. 相似文献
99.
Immunohistochemical,ultrastructural and biochemical studies of an amylase-producing breast carcinoma
Hideo Inaji Hiroki Koyama Masahiko Higashiyama Shinzaburo Noguchi Hitoshi Yamamoto Osamu Ishikawa Kaoru Omichi Takeshi Iwanaga Akira Wada 《Virchows Archiv : an international journal of pathology》1991,419(1):29-33
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen. 相似文献
100.
Ueno Shu-ichi; Kondoh Keiji; Komure Yasunori; Komure Osamu; Kuno Sadako; Kawai Jun; Hazama Fumitada; Sano Akira 《Human molecular genetics》1995,4(4):663-666
An unstable expansion of CAG repeat in the coding region ofthe DRPLA gene on chromosome 12p is the mutation specific forhereditary dentatorubralpallidoluysian atrophy (DRPLA). We studiedthe CAG expansion in brain and other tissues from six unre latedDRPLA patients. The CAG repeat lengths showed distinct difterencesbetween tissues. The sizes of the CAG expansion in various regionsof the brain except the cerebellum were generally larger byseveral repeats than in other peripheral tissues. Brain samplesshowed greater variation of the expansion compared with othertissues, but neither the size of the CAG expansion nor the degreeof CAG repeat variation parallels the detailed findings of neuropathologicalinvolvement. We conclude that somatic instabilities of the CAGrepeat cause tissue variability of the CAG repeat size in DRPLAbut other region or cell type-specific factors would be involvedto explain the selectivity of cell damage in DRPLA. 相似文献