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61.
Kuroda N Kohno N Iwamura S Hamaguchi N Ohara M Hirouchi T Zuno K 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2006,114(9):659-662
We present a case of granular cell tumor (GCT) occurring in the esophagus 7 years after operation for bronchial GCT. A 59-year-old Japanese man complained of epigastralgia, and endoscopic examination of the upper digestive tract disclosed a submucosal tumor in the lower esophagus. Histological examination of the endoscopic mucosal resection of the esophageal tumor showed a proliferation of neoplastic cells with an eosinophilic and granular cytoplasm. The cytoplasm of the neoplastic cells was histochemically positive for PAS stain and immunohistochemically positive for S-100. This tumor did not fulfill any of the diagnostic criteria for malignancy at either the macroscopic or microscopic level. I believe that this is the first case of GCT occurring metachronously in the respiratory and digestive tracts. Clinicians and pathologists should bear in mind that GCT may arise metachronously in the respiratory and digestive tracts. 相似文献
62.
Nao Torimoto Itsuko Ishii Ken-Ichi Toyama Masayuki Hata Kanako Tanaka Hitoshi Shimomura Hiroyoshi Nakamura Noritaka Ariyoshi Shigeru Ohmori Mitsukazu Kitada 《Drug metabolism and disposition》2007,35(3):484-492
CYP3A7 is a member of the human CYP3A family and a major form of P450 expressed in human fetal livers. Although CYP3A7 shares nearly 90% base sequence with CYP3A4, CYP3A7 shows striking functional differences in the catalytic preference for several substrates, such as dehydroepiandrosterone (DHEA) or dehydroepiandrosterone 3-sulfate (DHEA-3S). First, to clarify the reason for the differences between CYP3A7 and CYP3A4, a homology model of CYP3A7 was constructed using the CYP3A4 crystal structure. Because these two structures were similar, four kinds of chimeric enzymes were constructed to determine which sequences are important for exhibiting the characteristics of CYP3A7. The results of kinetic analysis of DHEA and DHEA-3S 16alpha-hydroxylations by CYP3A7, CYP3A4, and CYP3A chimeras suggested that the amino acid residues from Leu(210) to Glu(279) were important to express the specificity for substrates as CYP3A7. This region was on the F and G helices of the modeled CYP3A7. Furthermore, to assess which amino acid in this sequence is important for the substrate specificity of CYP3A7, a one-point mutation of CYP3A7 to CYP3A4 was made by site-directed mutagenesis. The mutants of K224T and K244E had lost DHEA and DHEA-3S 16alpha-hydroxylation activities. The mutants also greatly decreased the metabolism of testosterone, erythromycin, nevirapine, and triazolam relative to those activities of CYP3A7 wild-type enzyme. From these results, it is expected that CYP3A7 can recognize specific substrates using the lysines in F-G loops. 相似文献
63.
Up-regulation of inositol 1, 4, 5-trisphosphate receptor expression in atrial tissue in patients with chronic atrial fibrillation 总被引:6,自引:0,他引:6
Yamada J Ohkusa T Nao T Ueyama T Yano M Kobayashi S Hamano K Esato K Matsuzaki M 《Journal of cardiology》2002,39(1):57-58
BACKGROUND: Abnormal intracellular Ca2+ homeostasis occurs in chronic atrial fibrillation(AF). The intracellular Ca2+ concentration is regulated by ryanodine and inositol 1,4,5-trisphosphate (IP3) receptors. Changes occur in ryanodine receptors in atrial tissue from patients in chronic AF. Whether AF patients have alterations in atrial IP3 receptors was investigated. METHODS: IP3 receptor expression was analyzed in the right atrial myocardium from 13 mitral valvular disease (MVD) patients with AF (MVD/AF), 5MVD patients with normal sinus rhythm(MVD/NSR), and 8 control patients with NSR(tissue obtained during coronary artery bypass surgery). Hemodynamic and echocardiographic data were obtained preoperatively, and an immunohistochemical study was performed on the atrial tissue. RESULTS: The relative expression level of IP3 receptor protein was significantly greater in MVD/AF (0.75 +/- 0.26) than in MVD/NSR (0.42 +/- 0.13, p < 0.01), and both were significantly above the control value (0.14 +/- 0.08). The relative expression level of IP3 receptor mRNA was significantly greater in MVD/AF(0.028 +/- 0.008) than in control subjects (0.015 +/- 0.004, p < 0.01), but MVD/AF patients did not differ from MVD/NSR (0.020 +/- 0.006) patients. The relative expression levels of IP3 receptor protein and mRNA were higher in patients with left atrial dimension > or = 40 mm, pulmonary capillary wedge pressure > or = 10 mmHg, and right atrial pressure > or = 5 mmHg. IP3 receptors were overexpressed in the cytosol and at the nuclear envelope of atrial myocytes in MVD. CONCLUSIONS: Since chronic mechanical overload of the atrial myocardium increases IP3 receptor expression, especially in patients with chronic AF, up-regulation of IP3 receptors may be important in modulating intracellular Ca2+ homeostasis and initiating and/or perpetuating AF. 相似文献
64.
Serum heat shock protein 70 levels and lung cancer risk: a case-control study nested in a large cohort study. 总被引:3,自引:0,他引:3
Koji Suzuki Yoshinori Ito Kenji Wakai Miyuki Kawado Shuji Hashimoto Nao Seki Masahiko Ando Yoshikazu Nishino Takaaki Kondo Yoshiyuki Watanabe Kotaro Ozasa Takashi Inoue Akiko Tamakoshi 《Cancer epidemiology, biomarkers & prevention》2006,15(9):1733-1737
Chronic inflammation contributes to the process of carcinogenesis, but few epidemiologic studies have examined associations with risk of lung cancer. Relationships between lung cancer risk and serum levels of both heat shock protein 70 (Hsp70) and high-sensitivity C-reactive protein (hsCRP) were investigated in a case-control study nested in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk. Serum samples and lifestyle information were collected at baseline from 39,242 men and women between 1988 and 1990. Of these, 240 deaths from lung cancer were identified through 1999, and 569 controls were matched for sex, age, and study area. Serum levels were measured in 189 cases and 377 controls for Hsp70 and in 209 cases and 425 controls for hsCRP. Odds ratios (95% confidence intervals) across quartiles, adjusted for confounding factors, including smoking habits, were 0.83 (0.44-1.58), 1.41 (0.77-2.60), and 1.84 (0.92-3.71) for Hsp70 (P(trend) = 0.042) and 1.13 (0.67-1.91), 0.66 (0.38-1.16), and 1.19 (0.70-2.02) for hsCRP (P(trend) = 0.941). In males, odds ratios (95% confidence intervals) across quartiles were 1.30 (0.59-2.84), 1.74 (0.83-3.67), and 2.49 (1.06-5.85) for Hsp70 (P(trend) = 0.029). High levels of serum Hsp70 might thus be associated with increased risk of lung cancer among Japanese males, although further studies are needed to clarify associations between chronic inflammation and lung cancer. 相似文献
65.
Kenji Wakai Yoshinori Ito Koji Suzuki Akiko Tamakoshi Nao Seki Masahiko Ando Kotaro Ozasa Yoshiyuki Watanabe Takaaki Kondo Yoshikazu Nishino Yoshiyuki Ohno for the JACC Study Group 《Cancer science》2002,93(12):1279-1286
To elucidate the roles of insulin-like growth factors (IGFs) in the development of lung cancer, we conducted a case-control study nested within the Japan Collaborative Cohort Study. Serum samples were collected at baseline from 39 140 men and women between 1988 and 1990. We measured serum IGF-I, IGF-II, and IGF-binding protein-3 (IGFBP-3) in 194 case subjects who subsequently died from lung cancer during an 8-year follow-up and in 9351 controls. The odds ratios (ORs), adjusted for smoking and other covariates, were smaller with higher levels of IGF-II and IGFBP-3. The ORs across quartiles were 0.41 (95% confidence interval [CI], 0.27–0.63), 0.47 (0.31–0.71), and 0.67 (0.46–0.98) for IGF-II (trend P =0.018), and 0.55 (95% CI, 0.37–0.81), 0.54 (0.36–0.82), and 0.67 (0.45–1.01) for IGFBP-3 (trend P =0.037). These peptides were not independently related to lung cancer risk when mutually adjusted. The risk was increased in the highest vs. the lowest quartile of IGF-I only after controlling for IGFBP-3 (OR, 1.74; 95% CI, 1.08–2.81). Limiting subjects to those followed for ≥3 years strengthened the negative associations of IGF-II and IGFBP-3, whereas the ORs for IGF-I generally decreased. A higher level of circulating IGFBP-3 and/or IGF-II may decrease lung cancer risk. Elevated serum IGF-I may increase the risk, but this could partly be attributable to latent tumors. 相似文献
66.
Ayumi Denda Wakashi Kitayama Hideki Kishida Nao Murata Masahiro Tsutsumi Toshifumi Tsujiuchi Dai Nakae Yoichi Konishi 《Cancer science》2002,93(2):125-132
Development of hepatocellular carcinomas in rats caused by a choline-deficient, L-amino acid defined (CDAA) diet, usually associated with fatty liver, fibrosis, cirrhosis and oxidative DNA damage, has been recognized as a useful model of hepatocarcinogenesis caused by endogenous factors. In the present study, in order to further explore involved factors and genes, we established an equivalent model in spontaneous liver tumor-resistant C57BL/6J mice. Six-week-old males and females were continuously fed the CDAA diet and histological liver lesions and oxidative DNA damage due to 8-hydroxydeoxyguanosine (8-OHdG) were examined after 22, 65 and 84 weeks. In male mice, fatty change and fibrosis were evident at 22 weeks, and preneoplastic foci of altered hepatocytes were seen at an incidence of 8/8 (100%) and a multiplicity of 6.6±4.0 per mouse at 65 weeks. Hepatocellular adenomas and carcinomas developed at incidences of 16/24 (66.7%) and 5/ 24 (20.8%), and multiplicities of 1.421±1.32 and 0.29±0.62, respectively, at 84 weeks. The female mice exhibited resistance to development of these lesions. The CDAA diet also increased 8-OHdG levels in male but not female mice. These results indicate that a CDAA diet causes hepatocellular preneoplastic foci, adenomas and carcinomas associated with fibrosis and oxidative DNA damage in mice, as in rats, providing a hepatocarcinogenesis model caused by endogenous factors in mice. 相似文献
67.
Yamamichi N Yamamichi-Nishina M Mizutani T Watanabe H Minoguchi S Kobayashi N Kimura S Ito T Yahagi N Ichinose M Omata M Iba H 《Oncogene》2005,24(35):5471-5481
68.
Evaluation of TS-1 based treatment and expression of thymidylate synthase and dihydropyrimidine dehydrogenase on oral squamous cell carcinoma 总被引:1,自引:0,他引:1
Seventeen oral squamous cell carcinoma (SCC) patients underwent chemotherapy with TS-1 (8 males and 9 females, mean age; 75.1 years, range; 47-102 years). TS-1 permitted five cases of oral chemotherapy on an outpatient basis and 8 cases in elder patients over 80-years of age. Excepting five patients who underwent TS-1 therapy as post-operative adjuvant chemotherapy, the therapeutic efficacy of TS-1 in 12 patients with or without irradiation, surgery or chemotherapy resulted in 3 cases of complete response (CR), 6 cases of partial response (PR), 3 cases of stable disease (SD), with no progressive disease (PD) cases (overall response rate; 75%). SCC samples obtained from biopsy were immunohistochemically stained with anti-TS and DPD polyclonal antibody. Although the statistical significance was not clear, the expression of TS and DPD for CR cases was lower than that for SD cases. TS-1 therapy improved quality of life (QOL) especially in elder patients with oral SCC, and our immunohistochemical results suggested the predictive possibilities of TS and DPD expression in response to TS-1. 相似文献
69.
The source of patellofemoral pain is a common orthopaedic complaint that often is difficult to determine because of the lack of correlation between symptoms and specific clinical measurements. Excessive joint contact stresses resulting from patellofemoral malalignment and pathologic femoral shape often are associated with this pain. These measures are likely sensitive to the limb position (orientation and position relative to the imaging system with which they are quantified). Because of this sensitivity, the measures have large variations and do not show correlations with subjective symptoms. The purpose of this study was to determine if varying limb position resulted in significant changes in standard clinical measures of patellofemoral alignment and femoral shape. This dependence was investigated by simulating alterations in limb position through resectioning of three-dimensional magnetic resonance image sets (20 healthy knees) to create axial images with altered orientation (eight images) or location (four images) relative to a fixed reference. By quantifying the variability of the clinical measures across all images, it was determined that simulated alterations in limb position produced greater variability in femoral shape and patellofemoral alignment measures than the variability seen across control subjects. This indicated that a standardized method for establishing limb position relative to the imager is warranted. 相似文献
70.
Shimooka N Utsunomiya R Kubo S Hasegawa H Tominaga S Yoshimine T 《No shinkei geka. Neurological surgery》2005,33(6):595-598
A 59-year-old man presented with generalized convulsion. MR imaging demonstrated a homogeneously enhanced dural lesion infiltrating the parenchyma in the right parietal region. He had no history of sinusitis and the lesion a resembled malignant tumors, so surgical treatment was performed. The histopathological studies showed pachymeningitis extending to the cerebral parenchyma, so the diagnosis of pachymeningoencephalitis was made. After the operation, the patient had no neurological deficits and anticonvulsant therapy was continued. We report the third case of idiopathic local pachymenigoencephalitis that we could range extensively in the world. The clinical features and pathogenesis are discussed. 相似文献