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Dive into the research topics where Yasunari Tsuchihashi is active.

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Featured researches published by Yasunari Tsuchihashi.


Cancer | 1984

Analysis of DNA ploidy patterns of gastric carcinomas of Japanese

Takanori Hattori; Yohei Hosokawa; Masaru Fukuda; Hiroyuki Sugihara; Shinshichi Hamada; Tetsuro Takamatsu; Kazuo Nakanishi; Yasunari Tsuchihashi; Tadahisa Kitamura; Setsuya Fujita

Ploidy patterns of gastric carcinomas of 54 Japanese patients, ranging in age from 28 to 82 years, were determined by cytofluorometry. The gastric cancers were divided into four basic ploidy patterns; the first pattern was a diploid mode, the second was a heteroploid mode, the third was a mosaic pattern of a diploid and a heteroploid mode, and the fourth was a mosaic of two or more different heteroploid modes. The incidence was 68.4%, 14.8%, 12.9%, and 3.7% in the first, second, third, and fourth patterns, respectively. All the cancers contained polyploid populations, whereas the early cancers tended to contain a lesser amount of polyploid cells than the advanced ones. Diffuse‐type cancers and well‐differentiated, intestinal‐type adenocarcinomas were mostly unimodal cancers of the diploidy or heteroploidy, whereas poorly differentiated adenocarcinomas were often mosaic cancers of several different ploidies. There was no correlation between ploidy patterns and ages and sexes of patients. For 11 cases, labeling indices with 3H‐thymidine were determined. Labeling indices of the intestinal‐type and diffuse‐type cancers were 12% to 27% and 7% to 19%, respectively.


Cornea | 2004

Clinicopathologic study of conjunctivochalasis.

Akihide Watanabe; Norihiko Yokoi; Shigeru Kinoshita; Yoko Hino; Yasunari Tsuchihashi

Objective: To clarify the structural features of conjunctivochalasis histopathologically. Methods: A biopsy of redundant conjunctiva from the same anatomic location of 44 eyes with conjunctivochalasis was examined histologically. All patients, 9 men and 35 women, aged 66.6 ± 7.5 years (mean ± SD, 50.87 years), underwent conjunctivoplasty (termed tear meniscus reconstruction). Results: In all 44 cases, histologic examination disclosed normal conjunctival epithelium and negligible inflammation and lymphocyte infiltration; 39 patients manifested microscopic lymphangiectasia. Elastica van Gieson staining demonstrated elastic fiber fragmentation and sparsely assembled collagen fibers in all 44 cases. There was no discernible difference between specimens from patients with and without complications including tear-deficient dry eye, meibomian gland dysfunction, and clinically observable lymphangiectasia and/or pinguecula. Conclusion: Based on our histopathologic findings, we hypothesize that mechanical forces between the lower lid and conjunctiva gradually interfered with lymphatic flow. Chronic, prolonged mechanical obstruction of lymphatic flow may result in lymphatic dilation and eventually give rise to clinical conjunctivochalasis.


Acta Neuropathologica | 1981

Immunofluorescence studies of the monocytes in the injured rat brain

Yasunari Tsuchihashi; Tadahisa Kitamura; Setsuya Fujita

SummaryRat brain was obtained on the 4th day after its damage by a stab wound. The injured and the normal control brain tissues were stained by the immunofluorescence technique using anti-granulomonocytic rabbit serum. After the fluorescence observation the same tissues were further stained by hematoxylin and eosin (HE) and studied comparatively by light microscopy.The following results were obtained: (1) The normal adult rat brain lacks the cells which react with the antiserum, thus the resting microglia occurring in the normal adult brain are antigenically different from the cells of the monocyte-macrophage system. (2) In the injured brain tissues monocytes extravasate, enter brain parenchyma, and take ameboid forms or become macrophages. (3) Among the reactive cells in the injured brain, all of the brain macrophages and most of the ameboid cells were reactive with the antiserum thereby indicating their monocytic origin.


Acta Neuropathologica | 1984

Immunohistochemical studies of blood monocytes infiltrating into the neonatal rat brain

Toshihiko Miyake; Yasunari Tsuchihashi; Tadahisa Kitamura; Setsuya Fujita

SummaryBrains of normal rats ranging in age from newborn to adult were observed with immunofluorescence technique using anti-granulomonocyte antiserum.For the first 10 days after birth, many cells with positive fluorescence were found in the white matter, the subependyma, the extra-parenchymal spaces, and the leptomeninx, but very few in the gray matter. They were mononuclear, rich in cytoplasm, and globular or irregular in shape. After about day 10 p.n., the positive cells decreased in number and became slender. However, there was no change in the distribution pattern. After about 3 weeks of age, no positive cells were detected in the brain parenchyma, except for very rare necrobiotic ones.It was suggested that blood monocytes infiltrate into the brain parenchyma of normal neonatal rat, but only for a while in the limited areas (white matter and subependyma). They have the morphology and distribution of the “ameboid microglia” of neonatal brain. These monocytes disappear from the brain finally by the end of month 1 p.n.


Diagnostic Pathology | 2008

Use of virtual slide system for quick frozen intra-operative telepathology diagnosis in Kyoto, Japan.

Yasunari Tsuchihashi; Terumasa Takamatsu; Yukimasa Hashimoto; Tooru Takashima; Kooji Nakano; Setsuya Fujita

We started to use virtual slide (VS) and virtual microscopy (VM) systems for quick frozen intra-operative telepathology diagnosis in Kyoto, Japan. In the system we used a digital slide scanner, VASSALO by CLARO Inc., and a broadband optic fibre provided by NTT West Japan Inc. with the best effort capacity of 100 Mbps. The client is the pathology laboratory of Yamashiro Public hospital, one of the local centre hospitals located in the south of Kyoto Prefecture, where a fulltime pathologist is not present. The client is connected by VPN to the telepathology centre of our institute located in central Kyoto. As a result of the recent 15 test cases of VS telepathology diagnosis, including cases judging negative or positive surgical margins, we could estimate the usefulness of VS in intra-operative remote diagnosis. The time required for the frozen section VS file making was found to be around 10 min when we use ×10 objective and if the maximal dimension of the frozen sample is less than 20 mm. Good correct focus of VS images was attained in all cases and all the fields of each tissue specimen. Up to now the capacity of best effort B-band appears to be sufficient to attain diagnosis on time in intra-operation. Telepathology diagnosis was achieved within 5 minutes in most cases using VS viewer provided by CLARO Inc. The VS telepathology system was found to be superior to the conventional still image telepathology system using a robotic microscope since in the former we can observe much greater image information than in the latter in a certain limited time of intra-operation and in the much more efficient ways. In the near future VS telepathology will replace conventional still image telepathology with a robotic microscope even in quick frozen intra-operative diagnosis.


Journal of Pediatric Hematology Oncology | 2004

Successful treatment of congenital systemic juvenile xanthogranuloma with Langerhans cell histiocytosis-based chemotherapy.

Takuya Nakatani; Akira Morimoto; Ryuichi Kato; Sachiko Tokuda; Tohru Sugimoto; Kazuaki Tokiwa; Yasunari Tsuchihashi; Shinsaku Imashuku

Abstract: Juvenile xanthogranuloma (JXG), one of the most common forms of non-Langerhans cell histiocytosis (LCH), usually presents in young children as spontaneously regressing cutaneous lesions. However, the systemic type of JXG is difficult to treat in newborn infants, and fatal cases have been reported. In the patient described here, solid masses were discovered by fetal sonography during the 38th gestational week. At birth she had multiple tumors on the back, cheek, and hip as well as marked hepatosplenomegaly accompanied by respiratory failure. Laboratory results indicated pancytopenia, obstructive liver dysfunction, and coagulopathy. Brain magnetic resonance imaging revealed a tumor at the left pontine angle, and dysmorphic histiocytes were present in her spinal fluid. She was diagnosed with systemic JXG by histopathologic findings of the hip mass. The LCH-based multiagent chemotherapy including cytarabine, vincristine, methotrexate, and prednisolone ameliorated the symptoms rapidly. She was treated for 12 months and is currently doing well as a normally developing 2-year-old.


Acta Neuropathologica | 1978

Initial response of silver-impregnated "resting microglia" to stab wounding in rabbit hippocampus.

Tadahisa Kitamura; Yasunari Tsuchihashi; Setsuya Fujita

SummaryAdult rabbits received stab wound in the cerebrum and were sacrificed at intervals of 20, 30, and 39h thereafter. Each animal was injected intracere-brally with3H-thymidine 2 h before fixation. Altered brain tissues of the stratum radiatum of hippocampus were taken for examination. Response of “resting microglia” to stab wounding was investigated by electron microscopic autoradiography and by autoradiography applied on silver-impregnated materials. Following results were obtained: (1) Resting microglia undergo marked swelling shortly after the brain damage. We designate these cells as “swollen microglia”. (2) Swollen microglia form the only cell population that proliferate actively in the initial stage of glial response to the brain injury, and (3) astroglia do not proliferate during the same experimental periods, in the rabbit hippocampus.


Skeletal Radiology | 2001

Extraskeletal osteosarcoma arising in myositis ossificans

Eiichi Konishi; Katsuyuki Kusuzaki; Hiroaki Murata; Yasunari Tsuchihashi; John W. Beabout; K. Krishnan Unni

Abstract A 53-year-old woman had extraskeletal osteosarcoma that developed from a soft tissue bony mass present on the volar aspect of the left wrist for 4 years. Initially, the bony mass was soft and movable, but during the first year it became hard and fixed. The patient had no history of trauma. Because the lesion did not grow or cause any symptoms, the patient did not come to the hospital until 4 years after she first noticed the lesion. Radiologically, the bony mass had features characteristic of mature myositis ossificans, showing ”eggshell” ossification. A nonmineralized soft tissue mass occurred between the surface of the radius and the bony shell. Histologically, a high-grade osteosarcoma was present between the surface of the radius and the well-differentiated bone tissue, which included fatty and hematopoietic marrow. All the findings indicated that our patient had an extremely rare case of malignant transformation of myositis ossificans.


Cancer Letters | 1999

Elimination of Na+-dependent bile acid transporter from small intestine by ileum resection increase colonic tumorigenesis in the rat fed deoxycholic acid

Ryuhei Kanamoto; Naoyuki Azuma; Hitoshi Suda; Thoru Seki; Yasunari Tsuchihashi; Kimikazu Iwami

Abstract Ileal Na+-dependent bile acid transporter (ISBT) constituting a gateway to enterohepatic circulation of bile acids occurs exclusively at the distal site of the small intestine. In the present study, we examined colonic tumorigenesis promoted by deoxycholic acid in relation to the expression of the ISBT. For this purpose, the small intestine of a Fischer-344 rat was resected a length of 20 cm above the ileo-cecal valve (ileal resection) or below the duodenum (jejunal resection). Then, rats were treated with an intraperitoneal injection of azoxymethane (15 mg/kg body wt.) once a week for 3 weeks and fed a 20% casein diet supplemented with 0.2 % deoxycholate for 39 weeks. Northern blot analysis demonstrated that the ISBT mRNA was hardly detectable in ileum-resected rats. The excretion of fecal bile acids was 1.5-fold higher in the ileum-resected group than in the jejunum-resected group (P


Acta Neuropathologica | 1977

Electron microscopic features of the resting microglia in the rabbit hippocampus, identified by silver carbonate staining

Tadahisa Kitamura; Yasunari Tsuchihashi; Atsushi Tatebe; Setsuya Fujita

SummaryVibratome sections of hippocampus of adult rabbits were stained by a modified Hortegas silver-carbonate method. Impregnated materials were examined by electron microscopy to decide fine-structural characteristics of the resting microglia. Comparing their characteristics with those of macrophages, we came to the following conclusions:(1) Impregnated resting microglia in the hippocampus of adult rabbits can be identified as cells having distinct fine structures. (2) Resting microglia are morphologically different from macrophages or their precursor cells, and therefore, seem not to be hematogenous cells sojourning in the normal brain parenchyma.

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Tsukasa Ashihara

Kyoto Prefectural University of Medicine

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Setsuya Fujita

Kyoto Prefectural University of Medicine

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Tadashi Kodama

Kyoto Prefectural University of Medicine

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Kei Kashima

Kyoto Prefectural University of Medicine

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M. Kamachi

Kyoto Prefectural University of Medicine

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Hidetoshi Okabe

Shiga University of Medical Science

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Kazuhiko Tokita

Kyoto Prefectural University of Medicine

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Y. Urata

Kyoto Prefectural University of Medicine

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Hiroyuki Sugihara

Shiga University of Medical Science

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Yohei Hosokawa

Kyoto Prefectural University of Medicine

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