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951.
Sugai T Habano W Uesugi N Jiao YF Nakamura S Sato K Chiba T Ishii M 《The Journal of molecular diagnostics : JMD》2002,4(4):191-200
Although the Vienna classification has been introduced to resolve discrepancies in histological diagnoses of colorectal tumors between Western and Japanese pathologists, practical applications of this classification scheme have been problematic because invasion of the lamina propria of tumor cells is often difficult to recognize. Therefore, the following refinements of the classification criteria are needed: category 3, low-grade adenoma/dysplasia; category 4, intramucosal borderline neoplasia; 4-a, high-grade adenoma/dysplasia; 4-b, well-differentiated adenocarcinoma; category 5, definite carcinoma; 5-a, intramucosal moderately-differentiated adenocarcinoma; and 5-b, submucosal carcinoma. We attempted to test whether molecular genetic alterations are related to the modified classification scheme and whether they may help to further categorize the various intramucosal neoplasia grades of colorectal tumors. Two-hundred-thirty-two colorectal tumors were examined using flow cytometric analysis of DNA content, polymerase chain reaction microsatellite assays, and single-strand conformational polymorphism assays to detect abnormalities of DNA content, chromosomal allelic loss, and Ki-ras and p53 gene mutations. Microsatellite instability (MSI) was also examined. Frequencies of genetic alterations and DNA aneuploid states increased with an increase in the grade assigned according to the modified Vienna classification. MSI was a rare event in colorectal adenomas and their frequency of MSI did not correlate with tumor grade. The combined genetic and DNA ploidy data support the conclusion that analysis of genetic alterations and DNA aneuploid states may help in appropriate categorization of colorectal tumors according to the modified Vienna scheme. In addition, MSI-positive tumors may represent a specific subtype of colorectal adenomas. 相似文献
952.
Gen Nakamura Noriyuki Homma Akio Kasai Takuya Kasami Kunihiko Makino Youhei Aoki 《Modern rheumatology / the Japan Rheumatism Association》2013,23(3):551-557
AbstractWe report two cases of TAFRO syndrome, which is characterized by thrombocytopenia, anasarca, fever, renal insufficiency, and organomegaly. Magnetic resonance imaging (MRI) of the spine showed a dark medullary pattern in the bone marrow on the T1- and T2-weighted images of both patients. One patient showed complete resolution after treatment. Serial MRIs of the improved patient revealed a transition to a normal marrow pattern on both images, which might represent resolution of the disease. 相似文献
953.
954.
Iwamoto N Abe-Dohmae S Ayaori M Tanaka N Kusuhara M Ohsuzu F Yokoyama S 《Circulation research》2007,101(2):156-165
955.
Yamada N Yamazaki K Kurimoto N Asahina H Kikuchi E Shinagawa N Oizumi S Nishimura M 《Chest》2007,132(2):603-608
STUDY OBJECTIVES: To evaluate factors predicting the diagnostic yield of transbronchial biopsy (TBB) using endobronchial ultrasonography with a guide sheath (EBUS-GS) in small peripheral pulmonary lesions (PPLs) = 30 mm in mean diameter. DESIGN: Retrospective analysis. PATIENTS AND METHODS: One hundred fifty-five consecutive patients with 158 small PPLs underwent TBB using EBUS-GS. RESULTS: A definitive diagnosis was established by TBB using EBUS-GS in 106 PPLs (67%). The diagnostic yield of PPLs = 15 mm in mean diameter (40%) was significantly lower than that of PPLs > 15 mm and = 30 mm in mean diameter (76%; p < 0.001). PPLs in which the probe was positioned within the PPL on the endobronchial ultrasonography (EBUS) image had a higher diagnostic yield (83%) than PPLs in which the probe was positioned adjacent to the PPL (61%) or outside the PPL (4%; p < 0.001). There were no significant differences in diagnostic yield for underlying disease, location, CT scan bronchus sign, operator, or type of EBUS probe. In the multivariate analysis, only the position of the probe (within or adjacent to the PPL when judged against outside the PPL) was determined to be a significant factor predicting diagnostic yield. On the other hand, a pathologic diagnosis was established with the first, second, third, fourth, and fifth biopsy specimens in 65%, 80%, 87%, 91%, and 97% of PPLs, respectively. CONCLUSIONS: The position of the probe (ie, within or adjacent to the PPL) is a significant factor in predicting the diagnostic yield of TBB using EBUS-GS for small PPLs; the optimum number of biopsy specimens is at least five. 相似文献
956.
Aoki N Jin-no S Nakagawa Y Asai N Arakawa E Tamura N Tamura T Matsuda T 《Endocrinology》2007,148(8):3850-3862
Adipocytes are now recognized as endocrine cells secreting adipocytokines, regulating multiple metabolic pathways. In this study, we addressed secretion of microvesicles by 3T3-L1 adipocytes. We found that MFG-E8, one of the exosomal proteins, was present in the microvesicles and was distributed in the sucrose density fractions with 1.13-1.20 g/ml, which has been reported for exosomes. Several integral, cytosolic, and nuclear proteins such as caveolin-1, c-Src kinase, and heat shock protein 70 were also found to be microvesicle components. Unexpectedly, adiponectin was also substantially distributed in the microvesicle fractions. Furthermore, proteomic analysis of the microvesicles revealed that many other proteins such as extracellular matrix-related proteins were also present. Microvesicles secreted by 3T3-L1 adipocytes exhibited heterogeneity in size and comprised both smaller exosome-like and larger membrane vesicles as revealed by electron microscopy. Milk fat globule-epidermal growth factor 8 (MFG-E8)-associated adiposomes exhibited binding activity toward phosphatidylserine and apoptotic cells. MFG-E8 in the microvesicles was reduced when cultured in the low-glucose medium or cultured in the high-glucose medium with antioxidant N-acetyl cysteine. Insulin and TNF-alpha also up-regulated MFG-E8 in the microvesicles. Moreover, MFG-E8 was strongly up-regulated in the hypertrophic adipose tissue, predominantly in adipocyte fractions, of diet-induced obese C57BL/6 mice, where increased oxidative stress is induced. Thus, it is suggested that microvesicles, especially MFG-E8-associated ones, modulate adipose functions under redox- and hormone-dependent regulation. Based on the above findings, the adipocyte-derived microvesicles were named adiposomes. 相似文献
957.
Endo I Fukumoto S Ozono K Namba N Tanaka H Inoue D Minagawa M Sugimoto T Yamauchi M Michigami T Matsumoto T 《BONE》2008,42(6):1235-1239
Fibroblast growth factor 23 (FGF23) plays important roles in the development of hypophosphatemic diseases such as tumor-induced osteomalacia (TIO) and X-linked hypophosphatemic rickets/osteomalacia (XLH). However, clinical usefulness of measurement of FGF23 has not been established. The objective of this study is to examine the importance of FGF23 measurement in the diagnosis of hypophosphatemic diseases. Biochemical parameters concerning phosphate metabolism were analyzed in a cross-sectional study. 32 patients with TIO, 28 patients with XLH and 16 hypophosphatemic patients with other causes including vitamin D deficiency, Fanconi's syndrome and Cushing's syndrome were studied. In patients with TIO and XLH, FGF23 was above the upper limit of the reference range in most patients irrespective of medical treatment. The lowest FGF23 in these patients was 38.0 pg/ml. FGF23 in hypophosphatemic patients with other causes was undetectable (less than 3 pg/ml) in 12 patients and the highest FGF23 in this group was 23.9 pg/ml. Relationship between phosphate and FGF23 indicated that TIO and XLH are diseases with high FGF23 and hypophosphatemia judged by age-dependent reference ranges for serum phosphate. FGF23 measurement is useful for differential diagnosis of hypophosphatemic diseases caused by excess actions of FGF23 and other etiologies. High FGF23 with low phosphate judged by age-dependent reference ranges for phosphate establishes the diagnosis of diseases caused by excess actions of FGF23. 相似文献
958.
Sakata N Tashiro T Uesugi N Kawara T Furuya K Hirata Y Iwasaki H Kojima M 《The American journal of surgical pathology》2008,32(4):553-559
Inflammatory abdominal aortic aneurysm (IAA) is associated with autoimmune disease. However, the precise mechanism of IAA remains unclear. There is increasing evidence that IgG4 is involved in the autoimmune mechanism of various idiopathic sclerosing lesions, including sclerosing pancreatitis and retroperitoneal fibrosis. The present study investigated the hypothesis that the IgG4-related autoimmune reaction is involved in the formation of IAA. The study group consisted of 11 cases of IAA (69.2 +/- 8.59y) and 12 age-matched cases of atherosclerotic abdominal aortic aneurysm (AAA, 69.6 +/- 5.94y), which were used in the previous report. A clinicopathologic examination of these lesions was performed, including histology and immunohistochemistry, in relation to the involvement of IgG4-positive plasma cells in the formation of IAA. No difference in the incidence of risk factors for atherosclerosis was observed between the patients with IAA and AAA. Autoimmune diseases were diagnosed in 2 patients with IAA, including rheumatoid arthritis and polyarteritis nodosa. A patient with IAA had pulmonary fibrosis. In contrast, autoimmune diseases were absent in patients with AAA. However, there was no significant difference in the incidence of autoimmune diseases between the patients with IAA and AAA. Lymphocyte and plasma cell infiltration and fibrosis were significantly more intense and extensive in IAA than in AAA. In addition, lymph follicle formation and vasculitis of small veins and arteries were frequently found in the affected lesions of IAA. Immunohistochemically, IAA showed a significant increase in the number of infiltrating IgG4-positive plasma cells and the incidence of a disrupted follicular dendritic cell network in lymph follicles, in comparison with AAA. These findings suggest that IAA may be an aortic lesion reflecting the presence of IgG4-related sclerosing disease, and not a simple inflammatory aneurysm of the aorta. 相似文献
959.
Statistical image analysis of cerebral glucose metabolism in patients with cognitive impairment following diffuse traumatic brain injury 总被引:1,自引:0,他引:1
The aim of this study was to explore the regional cerebral glucose metabolism (rCM) in patients with chronic stage traumatic brain injury (TBI) compared with normal controls. We also investigated the relationship between regional cerebral glucose metabolism and cognitive function. We performed 2-[(18)F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) study using statistical parametric mapping (SPM) analysis in 36 diffuse axonal injury (DAI) patients (mean age +/- SD, 36.3 +/- 9.8 years). At 6 months or more after head injury, all patients underwent FDG-PET study and neuropsychological batteries to assess cognitive function. Thirty healthy, gender-matched control subjects who were comparable in age were also studied. Between the TBI patients and normal controls, group comparisons showed regional metabolic decreases in the bilateral frontal lobes, temporal lobes, thalamus, as well as the right cerebellum in the TBI group. Only full-scale Intelligence Quotient (IQ) (mean +/- SD, 78.5 +/- 11.9) correlated positively with rCM in the right cingulate gyrus and the bilateral medial frontal gyrus. In other examinations, the correlation was not provided. DAI may induce functional disconnection and decreased neuronal activity, and finally lead to diffuse glucose hypometabolism. Low full-scale IQ scores may be related to significantly different underlying cognitive impairment. In supporting cognitive function following TBI, which showed diffuse cerebral metabolic reduction compared with normal controls, medial prefrontal cortex and anterior cingulate cortex may be an important component. 相似文献
960.