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Dive into the research topics where Akihiko Sakata is active.

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Featured researches published by Akihiko Sakata.


Pathology International | 1996

Enhanced CD34 expression of sinusoid-like vascular endothelial cells in hepatocellular carcinoma.

Shunjin Cui; Hiroshi Hano; Akihiko Sakata; Toru Harada; Tiecheng Liu; Shigeharu Takai; Shinichiro Ushigome

The immunohistochemlcal expression of CD34 (human hematopoletic stem cell and endothelial cell marker) and laminin were studied In chronic liver diseases and hepate cellular carcinoma (HCC) to elucidate whether their expression reflected phenotypic differences between non‐cancerous slnusoids and sinusoid‐like tumor vessels. In normal liver, hepatic sinusoids were always negative for CD34 and lami‐nin. In chronic hepatitis and cirrhosis, the two antigens were sparsely expressed in capillarized sinusoids at periportal and petinodular area. In advanced HCC, CD34 was strongly and diffusely expressed by the endothelial lining of sinusoid‐like tumor vessels. However, early‐stage HCC showed a wide spectrum of CD34 expression from negative to focal and diffuse, strongly positive staining in sinusoid‐like vessels. Laminin was strongly expressed in advanced HCC but not in early‐stage HCC. The results Indicate that the enhanced expression of CD34 by sinusoidal endothelial cells may reflect the phenotypic change of endothellal cells in chronic liver diseases and HCC, and that the expression may correlate with the processes of angiogenesis induced by hepatocarcinogenesis.


Pathology International | 2008

A pathological study on eosinophilic lymphfolliculoid granuloma (Kimura's disease).

Eisei Ishikawa; Hisako Tanaka; Shinichi Kakimoto; Satoshi Takasaki; Yuji Kirino; Akihiko Sakata; Masafumi Suzuki

The present study Included 46 cases of eosinophilic lymphfolliculoid granuloma(Kimuras disease), which occurred mainly in males between the ages of 11 to 52 years. The common sites were the soft tissue of the head and neck region. Although recurrence was not infrequent, the clinical course was benign. Laboratory findings revealed eosinophilia and frequent elevation of serum IgE. The histological characteristics consisted of proliferation of lymphoid follicles and granulation tissue with infiltration of eosinophils, mast cells, plasma cells, lymphocytes, and histiocytes, some degree of vascular proliferation, and fibrosis. With the appliance of unlabeled peroxidase‐antiperoxidase method, a marked reticular reaction of IgE was confirmed in the germinal center of the folliculoid structure, and there were quite a number of IgE producing plasma cells. Many mast cells with IgE bound to their cell surface were seen in the granulation tissue. Toluidine blue staining and electron microscopy revealed fairly well preserved granules in mast cells, being quite different from the changes seen in type I allergy.


Pathology International | 1984

Lymphocyte Subsets in The white Pulp of Human Spleen in Normal and Diseased Cases

M D Hisako Tanaka; Satoshi Takasaki; Akihiko Sakata; Tetsuya Muroya; Teruo Suzuki; Eisei Ishikawa

The distribution of T and B‐lymphocytes and their subsets in the white pulp of human spleens extirpated from patients with cancer of the digestive tract and those with portal hypertension was examined with the appliance of monoclonal antibodies. T‐lymphocytes were distributed in the core of lymphatic sheath protuberance (Matsumoto), while the mantle zone of lymphatic nodule and germinal center were solely occupied by B‐lymphocytes. On the other hand, both T and B‐lymphocytes were found in the cortical zone of lymphatic sheath protuberance and outer and inner layer of lymphatic nodule. The ratio of both cells differed from one case to the other. The majority of T‐lymphocytes in the core of lymphatic sheath protuberance and those localized in the light region of germinal center were helper T cells. Although the lymphatic sheaths in cases with portal hypertension were narrower than those in the controls, there was no difference in the distribution density of T cells between the two groups. Hardly any B‐lymphocytes were found in the cortical zone of lymphatic sheath protuberance, while the mixture of T‐lymphocytes tended to become prominent in the outer and inner layer of lymphatic nodule in those cases.


Japanese Journal of Ophthalmology | 1998

Phakomatous choristoma of the eyelid: Immunohistochemical observation

Yoshio Kamada; Akihiko Sakata; Satoshi Nakadomari; Makoto Takehana

This article reports the first case of phakomatous choristoma of the eyelid in Japan. The tumor occurred in a 2-week-old boy and was located in the left lower lid near the inner canthus. An immunohistochemical study of this rare, congenital tumor was performed. The immunohistochemical analysis revealed that the epithelial cells of this tumor showed positive staining for vimentin, S-100 protein, and neuron-specific enolase, while they had no immunoreactivity for cytokeratin, glial fibrillary acidic protein, epithelial membrane antigen, or a macrophage marker. Both the epithelial cells and the central contents of the islands in this tumor showed positive staining with anti-human alpha crystallin monoclonal mouse IgG. These results strongly indicated that a phakomatous choristoma was of a lenticular origin.


International Journal of Urology | 1999

Case of gonadoblastoma in a 9‐year‐old boy without physical abnormalities

Takashi Hatano; Yasumasa Yoshino; Yoshio Kawashima; Hiroshi Shirai; Norio Iizuka; Yoshio Miyazawa; Akihiko Sakata; Tetsuro Onishi

Background: A 9‐year‐old boy was admitted to Jikei University Hospital complaining of gradual enlarging of the left scrotal contents.


European Journal of Gastroenterology & Hepatology | 2015

Centrilobular zonal necrosis as a hallmark of a distinctive subtype of autoimmune hepatitis

Yoshio Aizawa; Hiroshi Abe; Tomonori Sugita; Nobuyoshi Seki; Yoshimichi Chuganji; Youhei Furumoto; Akihiko Sakata

Background and aim Centrilobular zonal necrosis (CZN) is a known histological variant of autoimmune hepatitis (AIH). However, the significance of CZN is yet to be fully elucidated. This study aimed to determine whether CZN is a hallmark of a distinctive subtype of AIH. Methods Histological changes in the centrilobular zones of liver biopsies from 113 AIH patients were assessed by a single pathologist and classified into three categories: typical zonal necrosis defined as CZN (15 patients); other necroinflammatory change (NIC; 24 patients); and absence of necrosis (non-NIC; 74 patients). The clinicopathological features and immunogenetic background of CZN patients were then assessed. Results The clinicopathological features of AIH with CZN were distinct from other types of AIH, including a higher frequency of acute onset, lower frequency of antinuclear antibodies, lower antinuclear antibody titers, lower serum immunoglobulin G levels, lower grade interface hepatitis, less prominent lymphoplasmacytic infiltration, and lower AIH score. Increased and decreased frequencies of HLA-DR9 and HLA-DR4, respectively, were identified as immunogenetic features of AIH with CZN. Conversely, the clinicopathological characteristics of AIH with NIC were similar to those of non-NIC AIH, including the majority of the AIH patients. The therapeutic outcomes of AIH with CZN were excellent when precise diagnoses were made without delay. Conclusion The clinicopathological features and immunogenetic background of AIH with CZN differed from AIH without CZN. CZN may be a hallmark of a distinct subtype of AIH.


Clinical Journal of Gastroenterology | 2014

Early syphilitic hepatitis concomitant with nephrotic syndrome followed by acute kidney injury

Kenichi Yoshikawa; Yuta Aida; Nobuyoshi Seki; Tamihiro Miyazaki; Munenori Itagaki; Haruya Ishiguro; Hiroshi Abe; Satoshi Sutoh; Akihiko Sakata; Yoshio Aizawa

Although acute hepatitis and nephrotic syndrome are commonly reported as complications of tertiary syphilis, nephrotic syndrome concomitant with hepatitis in early-stage syphilis is rare. Here, we describe the case of a 46-year-old male who was diagnosed with acute liver dysfunction and nephrotic syndrome after presenting with general malaise, and who subsequently developed acute kidney injury. Laboratory examination showed alkaline phosphatase had a greater magnitude of elevation compared to alanine aminotransferase, suggesting the possibility of syphilitic hepatitis. The rapid plasmin regain test and Treponema pallidum hemagglutination assay were positive, supporting the presence of a syphilis infection. Additionally, liver biopsy examination showed infiltration of inflammatory cells into the portal area and epithelioid cell granulomas. Moreover, kidney biopsy examination by both optical and electron microscopy showed a congestion of neutrophils in the capillary vessels, structural collapse of the tubules, and subepithelial deposits under the epithelium of the glomerular endothelial cells. These pathological changes were consistent with those reported previously for early syphilitic hepatitis and nephrotic syndrome in early-stage syphilis. All the symptoms, including liver and renal dysfunction, resolved after benzyl penicillin treatment was initiated. Hence, we believe early-stage syphilis should be included in the differential diagnosis of unknown liver damage and/or nephrosis.


Gynecologic Oncology | 2004

Overexpression of HER-2/neu is not a risk factor in ovarian clear cell adenocarcinoma

Hiroshi Tanabe; Hiroshi Nishii; Akihiko Sakata; Keitaro Suzuki; Yukiko Mori; Hideo Shinozaki; Akihiko Watanabe; Kazuhiko Ochiai; Makoto Yasuda; Tadao Tanaka


BMC Gastroenterology | 2015

Evaluation of the role of HLA-DR antigens in Japanese type 1 autoimmune hepatitis

Yohei Furumoto; Toru Asano; Tomonori Sugita; Hiroshi Abe; Yoshimichi Chuganji; Kazuhiko Fujiki; Akihiko Sakata; Yoshio Aizawa


Kanzo | 2011

A case of primary biliary cirrhosis associated with hepatocellular carcinoma and systemic lupus erythematodes

Haruya Ishiguro; Takazumi Kimura; Toshiki Nikami; Kai Yoshizawa; Hiroshi Abe; Satoshi Sutou; Yoshio Aizawa; Akihiko Sakata; Hisao Tajiri

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Hiroshi Abe

Jikei University School of Medicine

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Yoshio Aizawa

Jikei University School of Medicine

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Eisei Ishikawa

Jikei University School of Medicine

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Haruya Ishiguro

Jikei University School of Medicine

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Hiroshi Hano

Jikei University School of Medicine

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Nobuyoshi Seki

Jikei University School of Medicine

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Satoshi Takasaki

Jikei University School of Medicine

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Tomonori Sugita

Jikei University School of Medicine

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Akihiko Watanabe

Jikei University School of Medicine

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