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101.
102.
Kavindra Kumara Wijesundera Vetnizah Juniantito Hossain M. Golbar Kae Fujisawa Miyuu Tanaka Chisa Ichikawa Takeshi Izawa Mitsuru Kuwamura Jyoji Yamate 《Experimental and toxicologic pathology》2013,65(6):799-808
Ionized calcium binding adaptor molecule 1 (Iba1) is associated with membrane ruffling and motility of cells. Galectin-3 (Gal-3) is a β-galactoside binding animal lectin, and regulates fibrogenesis probably through transforming growth factor-β1. To evaluate macrophage properties, expressions of Iba1 and Gal-3 were investigated, in relation to macrophages expressing CD68 (ED1; reflecting increased phagocytosis) and CD163 (ED2; implying proinflammatory factor productions) in centrilobular lesions induced in rat livers with thioacetamide (TAA; 300 mg/kg body weight, once intraperitoneally). In agreement with expression patterns of CD68+ and CD163+ macrophages, cells reacting to Iba1 and Gal-3 were increased in numbers on post-injection (PI) days 1–5, peaking on day 2; thereafter, the positive cells gradually decreased to control levels until PI days 7 and 10. The increased expressions of Iba1 and Gal-3 were confirmed at mRNA levels by the RT-PCR. Double immunofluorescence staining on PI days 2 and 3 demonstrated Iba1 expression in 15–46% of CD68+ and CD163+ macrophages, and Gal-3 expression in 65–82% of CD68+ and CD163+ macrophages; Gal-3 expression was observed in 84–93% of Iba1+ cells. Interestingly, Gal-3 was also expressed in a small number of α-smooth muscle actin-positive myofibroblasts in fibrotic lesions developed in injured centrilobular areas. These findings indicate that macrophages with various functions can participate in development of liver lesions and resultant fibrosis. Besides CD68 and CD163, Iba1 and Gal-3 immunohistochemistry for macrophages would be useful to analyze the pathogenesis behind developing hepatotoxicity. 相似文献
103.
Yohei Miura Katsuhiro Ichikawa Ichiro Fujimura Takanori Hara Takashi Hoshino Shinji Niwa Masao Funahashi 《Radiological physics and technology》2018,11(1):54-60
The 320-detector row computed tomography (CT) system, i.e., the area detector CT (ADCT), can perform helical scanning with detector configurations of 4-, 16-, 32-, 64-, 80-, 100-, and 160-detector rows for routine CT examinations. This phantom study aimed to compare the quality of images obtained using helical scan mode with different detector configurations. The image quality was measured using modulation transfer function (MTF) and noise power spectrum (NPS). The system performance function (SP), based on the pre-whitening theorem, was calculated as MTF2/NPS, and compared between configurations. Five detector configurations, i.e., 0.5 × 16 mm (16 row), 0.5 × 64 mm (64 row), 0.5 × 80 mm (80 row), 0.5 × 100 mm (100 row), and 0.5 × 160 mm (160 row), were compared using a constant volume CT dose index (CTDIvol) of 25 mGy, simulating the scan of an adult abdomen, and with a constant effective mAs value. The MTF was measured using the wire method, and the NPS was measured from images of a 20-cm diameter phantom with uniform content. The SP of 80-row configuration was the best, for the constant CTDIvol, followed by the 64-, 160-, 16-, and 100-row configurations. The decrease in the rate of the 100- and 160-row configurations from the 80-row configuration was approximately 30%. For the constant effective mAs, the SPs of the 100-row and 160-row configurations were significantly lower, compared with the other three detector configurations. The 80- and 64-row configurations were adequate in cases that required dose efficiency rather than scan speed. 相似文献
104.
105.
Harunobu Sato Tetsuya Tsukamoto Yoshihisa Mizuno Tomoaki Ichikawa Yoshihito Kotani Katsuyuki Honda Kouhei Hatta Makoto Kuroda 《Digestive endoscopy》2014,26(6):749-751
Malakoplakia in the gastrointestinal tract is rare in healthy young people without underlying disease. Sufficient tissue is required for accurate diagnosis. We describe a malakoplakia that developed in a healthy young woman and was treated by endoscopic mucosal resection (EMR). A 40‐year‐old woman with a history of taking oral contraceptives until one year earlier was referred to our hospital with anal bleeding and constipation. A colonoscopy carried out at our another hospital 18 months earlier disclosed no abnormal findings. Colonoscopy at presentation revealed a yellowish‐white tumor, 5 mm in diameter, in the rectum. The lesion was slightly protruded and had a smooth flat surface, without erosion or ulceration. EMR was carried out for a definitive diagnosis. Histopathological examination showed that the tumor contained granular histiocytes, positive for CD68 and negative forcytokeratin (AE1/AE3). Several histiocytes contained intracytoplasmic round bodies (Michaelis–Gutmann bodies), which reacted positively with periodic acid‐Schiff and calcium (Von Kossa) stains. Intracytoplasmic Escherichia coli (von Hansemann bodies) were identified by Giemsa staining. Based on these results, the tumor in the rectum was diagnosed as a malakoplakia. Following EMR, the patient did not receive further treatment for malakoplakia because she had no symptoms associated with malakoplakia. She has been well for more than 9 months, with no symptoms of disease. Awareness of colorectal malakoplakia is important in patients taking steroids, including oral contraceptives. 相似文献
106.
107.
We report a rare case of a patient in whom severe subcutaneous and mediastinal emphysema occurred in association with summer-type hypersensitivity pneumonitis and in whom overdistention or disruption of alveoli with obliteration of the respiratory bronchioles was revealed on open lung biopsy. This case suggests that obstructive bronchiolitis with hypersensitivity pneumonitis is an etiologic factor of mediastinal emphysema. 相似文献
108.
Okuzawa A Kobayashi S Sakamoto K Uchida Y Suzuki Y Ono K Seki E Tomiki Y Iwanuma Y Hayashida Y Kamano T Tsurumaru M 《Journal of gastroenterology》2000,35(9):717-720
Gastrinoma is a rare endocrine tumor that is frequently associated with liver metastasis. The liver metastasis is usually
seen simultaneously or soon after a primary operation. A 47-year-old woman who had had a total gastrectomy 20 years earlier
developed liver metastasis. An interval of this length between surgery and metastasis is extremely rare. The total gastrectomy
prevented the patient from developing the usual symptoms of hypergastrinemia that would have enabled early diagnosis of the
metastasis. Laboratory examinations on admission revealed a high serum gastrin concentration (1500 pg/ml). Computed tomography
showed an irregularly enhanced mass lesion with an uneven, low-density central area in the right anterior inferior segment
of the liver. An extended right hepatectomy was performed. Intraoperative ultrasonography showed no abnormalities in the remnant
pancreas. Examination of the cut surface of the specimen revealed a yellow, firm, elastic tumor, 55 mm in diameter. The interior
of the tumor appeared necrotic. Histopathologically, the tumor was composed of cells with hyperchromatic, dysplastic nuclei
arranged in a trabecular pattern with nest formation. Gastrin staining was positive. A histologic diagnosis of metastatic
gastrinoma was made. The patient's gastrin concentration returned to normal and she was well at 2-year follow-up.
Received: August 19, 1999 / Accepted: January 28, 2000 相似文献
109.
110.
Hormone replacement therapy causes a decrease in hepatocyte growth factor in hypertensive women 总被引:2,自引:0,他引:2
Tamama K Sumino H Ichikawa S Kanda T Kotajima N Fukumura Y Kurabayashi M Murakami M 《Journal of hypertension》2003,21(6):1151-1156
OBJECTIVE: Serum hepatocyte growth factor (HGF) is associated with blood pressure. We investigated whether the serum HGF level differs between hypertensive and normotensive postmenopausal women (PMW) and whether hormone replacement therapy (HRT) alters the serum HGF level and blood pressure in hypertensive and normotensive PMW. DESIGN: Prospective observational study. METHODS: A total of 33 PMW with mild to moderate essential hypertension controlled by antihypertensive treatment (mean age, 57 +/- 6 years) and 23 normotensive PMW (mean age, 57 +/- 7 years) received continuous HRT (0.625 mg of conjugated equine estrogen combined with 2.5 mg of medroxyprogesterone acetate) once a day orally for 12 months, and we measured serum HGF levels and blood pressure before and 12 months after the start of HRT. RESULTS: The baseline serum HGF level was significantly higher in hypertensive PMW than in normotensive PMW. HRT significantly decreased the serum HGF level in hypertensive subjects, from 2.85 +/- 0.64 pmol/l to 2.49 +/- 0.65 pmol/l (P < 0.001), but not in normotensive subjects. HRT did not change blood pressure in either group. CONCLUSIONS: Serum HGF level before the start of HRT was higher in the hypertensive PMW than in the normotensive PMW. Furthermore, HRT decreases serum HGF without decreasing blood pressure in hypertensive PMW. The HRT-induced decrease in serum HGF was greater in hypertensive PMW than in normotensive PMW, and the decrease was independent of blood pressure changes. 相似文献