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41.
Changes in the levels of urea cycle enzymes and polyamine metabolism in the liver of rats treated with alpha-naphthylisothiocyanate (ANIT), an inducer of experimental cholestasis, were studied. Activities of arginase increased approximately two-fold compared to the control values during the period of 24-72 hours after oral administration of ANIT (100 mg/kg), while activities of ornithine carbamyltransferase and ornithine aminotransferase decreased. The activity of ornithine decarboxylase was elevated by approximately 20- and 10-fold at 12 and 60 hours, respectively, after ANIT administration. Putrescine concentration doubled 24-48 hours after the ANIT administration, but spermidine level rose more slowly and reached the level of 1.5-fold of the control level in 36-72 hours. Spermine concentration decreased initially but increased in 96 hours. These results suggest that the increased activity of urea cycle accounts for the increase in the ornithine content and that the putrescine and spermidine acts as the initiator of recovery of the liver damaged by ANIT treatment. 相似文献
42.
43.
J Kusakari K Hozawa T Hanazima S Suzuki T Takasaka N Sasano 《Archives of oto-rhino-laryngology》1987,244(4):246-248
We report a case of cylindrical cell papilloma of the paranasal sinuses. This tumor originated in the medial wall of the left maxillary sinus of a 69-year-old man and extended to the surrounding tissues. Pathological study of tissue sections from the tumor showed typical findings of cylindrical cell papilloma with no evidence of associated malignancy. Histochemical and electron microscopic examinations revealed a large number of mitochondria in the cytoplasm of the tumor cells. The tumor was removed through a Denker's approach. The patient did well following surgery and there has been no sign of recurrence in a 2-year follow-up study. 相似文献
44.
Kazuta Fukumori Yoichi Yano Koutaro Kuwaki Shuji Sumie Eiji Ando Masatoshi Tanaka Michio Sata 《Nihon Shokakibyo Gakkai zasshi》2007,104(8):1225-1230
A 64-year-old man was admitted for further examinations of a liver tumor. The patient was diagnosed as chronic hepatitis C complicated with advanced hepatocelluar carcinoma (HCC) with left portal vein tumor thrombosis. As he refused surgical treatment, hepatic arterial infusion chemotherapy (HAIC) using cisplatin and 5-fluorouracil was performed initially. Administration of ursodesoxycholic acid (UDCA) was also started. Following HAIC, microwave coagulation therapy for residual tumor was added. Consequently, viable lesions of HCC disappeared completely. At present, after more than 8 years, neither signs of tumor recurrence, nor elevation of hepatic enzymes has been observed. Although the precise reason for long survival of this patient is not known, we speculate that suppression of levels of hepatic enzymes, as well as HAIC for subclinical intrahepatic metastasis, contributed to the good outcome. Therapeutic strategy for hepatic inflammation seems to be important for long-term prevention of hepatocarcinogenesis. 相似文献
45.
Toshihiko Imakiire Yuichi Kikuchi Muneharu Yamada Taketoshi Kushiyama Keishi Higashi Naomi Hyodo Kojiro Yamamoto Takashi Oda Shigenobu Suzuki Soichiro Miura 《Hypertension research》2007,30(7):635-642
The mechanisms of hypertensive nephrosclerosis are not fully understood. In experimental models of the disease, inflammatory reactions such as macrophage infiltration play an important role. In human hypertensive nephrosclerosis, however, there have been few studies examining the role of inflammation histologically. We investigated whether the number of infiltrating macrophages was increased in human hypertensive nephrosclerosis, and evaluated the effects of a blockade of the renin-angiotensin system on clinical and histological findings. We examined macrophage infiltration using immunohistochemistry in renal biopsy specimens obtained from 16 patients with hypertensive nephrosclerosis, 5 patients with IgA nephropathy, 5 patients with membranous nephropathy, and 5 patients with minimal change nephrotic syndrome. The number of infiltrating macrophages in glomeruli was significantly larger in the patients with hypertensive nephrosclerosis than in those with minimal change nephrotic syndrome. The patients with hypertensive nephrosclerosis were divided into groups based on their use of antihypertensive agents at the time of renal biopsy. We investigated the effects of antihypertensive agents on clinical findings, macrophage infiltration, and monocyte chemoattractant protein-1 expression. There was no difference in clinical findings between the hypertensive groups. The numbers of infiltrating macrophages and monocyte chemoattractant protein-1-positive cells in glomeruli were significantly smaller in patients treated with an angiotensin-converting enzyme inhibitor or angiotensin II type 1 receptor blocker, whereas calcium channel blockers had no influence on histological findings. In conclusion, inflammation is involved in the progression of human hypertensive nephrosclerosis and the inflammatory process is inhibited by blocking the renin-angiotensin system. 相似文献
46.
Keisuke Morita MD ; Kazunori Urabe ; Yoichi Moroi ; Tetsuya Koga ; Ryuji Nagai ; Seiko Horiuchi ; Masutaka Furue 《Wound repair and regeneration》2005,13(1):93-101
Advanced glycation end products are the chemical modification of proteins induced by sugars in a hyperglycemic condition. Extracellular matrix proteins are prominent targets of nonenzymatic glycation because of their slow turnover rates. The aim of this study was to investigate the influence of nonenzymatic glycation of type I collagen on the migration of keratinocytes. The migration of keratinocytes was dramatically promoted on native type I collagen-coated dishes compared with that on uncoated dishes. When type I collagen was glycated with glycolaldehyde, large amounts of advanced glycation end products were produced; the glycated collagen I-coated dishes did not promote the migration of keratinocytes. Glycated collagen I did not affect the proliferative capacity of keratinocytes. However, the adhesion of keratinocytes to glycated collagen I was profoundly diminished in a glycation intensity-dependent manner. alpha2beta1 integrin is responsible for the migration and adhesion of keratinocytes to type I collagen. Pretreatment with glycated collagen I did not affect the expression level or functional activity of alpha2beta1 integrin on keratinocytes. These findings suggest that in the presence of glycated collagen I, keratinocytes lose their adhesive and migratory abilities. As the glycation did not modify the alpha2beta1 integrin on keratinocytes, it is suggested that glycation may diminish the binding capacity of type I collagen. 相似文献
47.
Mikio Mikami Chisei Tei Kyoko Takehara Shinichi Komiyama Atsushi Suzuki Takanori Hirose 《International journal of gynecological pathology》2003,22(2):205-208
A 38-year-old female presented with a lower abdominal mass. During the operation the mass was found to be retroperitoneal and was excised. Gross examination revealed a mucin-containing cystic lesion with a mural nodule. On microscopic examination, the cystic areas were lined by an invasive mucinous adenocarcinoma and the nodule was composed of an anaplastic sarcomatoid tumor that was immunoreactive for cytokeratin. This present case is the 21st example of a retroperitoneal primary mucinous cystadenocarcinoma and the fourth with a mural nodule. Three of four cases with a mural nodule, including our case, had a rapidly fatal outcome. 相似文献
48.
49.
Yasuhiro Takikawa Yuki Yasumi Akihiro Sato Ryujin Endo Kazuyuki Suzuki Yasuki Mori Hidetoshi Akasaka Yasuhiro Miura Takashi Sawai Hiroaki Okamoto 《Hepatology research》2007,37(2):158-165
A 65-year-old Japanese man was hospitalized because of acute hepatitis and severe cholestasis due to hepatitis E virus (HEV) infection combined with a drug reaction to a cold preparation. He died of disseminated intravascular coagulation and severe intestinal bleeding due to systemic cytomegalovirus reactivation following the development of severe eruptions with marked eosinophilia due to drug hypersensitivity to taurine and ursodeoxycholate preparations. The close interaction between viral infection or reactivation and drug hypersensitivity was considered as a pathophysiology in this case, which emphasizes the need for further study of the immunological mechanism of the interaction. 相似文献
50.
D Craig Willcox Bradley J Willcox Sanae Shimajiri Sayuri Kurechi Makoto Suzuki 《The American journal of geriatric psychiatry》2007,15(3):252-256
OBJECTIVE: This study retrospectively explored the late-life functional status of Okinawan centenarians. METHODS: Activities of daily living were measured retrospectively at five time points (10, 5, 3, and 1 year prior and present) for 22 centenarians in relation to seven physical, two sensory, and two cognitive functions using the Inoue Index. RESULTS: In all, 82% of individuals were still functioning independently at a mean age of 92 years and almost two-thirds were still functioning independently at a mean age of 97 years. CONCLUSION: Preliminary analyses suggest high functional status in Okinawan centenarians throughout their 90 s. The genetic and environmental factors contributing to this successful aging phenomenon deserve further investigation. 相似文献