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Dive into the research topics where Kazuhiro Tasaki is active.

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Featured researches published by Kazuhiro Tasaki.


Pathology International | 1999

Analysis of the immunoglobulin heavy chain gene variable region of 101 cases with peripheral B cell neoplasms and B cell chronic lymphocytic leukemia in the japanese population.

Naoya Nakamura; Tetsuo Kuze; Yuko Hashimoto; Kazuhiro Tasaki; Hiroshi Hojo; Yoshikazu Sasaki; Michiko Sato; Masafumi Abe

We have analyzed the immunoglobulin heavy chain (VH) gene variable regions (CDR2 and FW3) of 101 Japanese cases with peripheral B cell neoplasms. When all except one case with a deletion were graphed by frequency of replacement mutation, the 100 cases could be separated into two groups: 24 cases with zero, one and two mutations (germline or low frequency of somatic mutation); and 76 cases with three or more mutations (medium to high frequency of somatic mutation). While most mantle cell lymphoma cases (11/13) showed germline or low frequency of somatic mutation, all cases of mucosa‐associated lymphoid tissue (MALT) lymphoma (11/11), follicular lymphoma (three of three cases), plasma cell myeloma (seven of seven cases) and most cases of diffuse large B cell lymphoma (DLBCL; 42/47) belonged to the latter group. These 76 cases, therefore, may be considered to show somatic hypermutation. More than half of chronic lymphocytic leukemia/small lymphocytic lymphoma cases (CLL/SLL; eight of 13) showed a hypermutated VH gene and the ratio of replacement mutation : silent mutation in CDR2 of CLL/SLL was considerably higher compared with DLBCL and MALT lymphoma, showing somatic hypermutation. When comparing VH gene type of B cell‐CLL (B‐CLL) among our series and those in the literature, more cases of CD5+ B‐CLL in the Western literature have the VH5 and VH6 family types, while more cases in Japan are reported to have VH4 family. The occurrence of VH families in B‐CLL between Japanese and Western people seems to be comparable.


Neurobiology of Aging | 2012

A unique N-glycan on human transferrin in CSF: a possible biomarker for iNPH

Satoshi Futakawa; Kiyomitsu Nara; Masakazu Miyajima; Atsushi Kuno; Hiromi Ito; Hiroyuki Kaji; Keiro Shirotani; Takashi Honda; Yuriko Tohyama; Kyoka Hoshi; Yusuke Hanzawa; Shinobu Kitazume; Rie Imamaki; Katsutoshi Furukawa; Kazuhiro Tasaki; Hiroyuki Arai; Tatsuhiko Yuasa; Masafumi Abe; Hajime Arai; Hisashi Narimatsu; Yasuhiro Hashimoto

Idiopathic normal pressure hydrocephalus (iNPH) is an elderly dementia caused by abnormal metabolism in the cerebrospinal fluid (CSF). The tap test is the current basis for confirming iNPH, but it shows very low sensitivity, indicating that many patients who might be cured by a shunt operation will be missed. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, we found two transferrin isoforms: one had a unique N-glycan (Tf-1) whereas the other had N-glycan similar to that of serum transferrin (Tf-2). Glycan analyses revealed that Tf-1 had branching (biantennary) asialo- and agalacto-complex type N-glycans (N-acetylglucosamine [GlcNAc]-terminated glycans), which carried bisecting β1,4-N-acetylglucosamine and core α1,6-fucose. To examine glycoform whether changes in iNPH, we introduced the Tf-2/Tf-1 ratio as a diagnostic index, which minimized blot-to-blot variations in measurement. The Tf-2/Tf-1 ratios of iNPH patients are significantly higher than those of controls (p = 0.0019) and Alzheimers patients (p = 0.0010). This suggests that the Tf-2/Tf-1 ratio could distinguish iNPH from Alzheimers disease, and possibly other dementias. In conclusion, glycoform analysis has diagnostic potential in neurological diseases.


Digestive Endoscopy | 2012

Prospective evaluation of the optimal number of 25-gauge needle passes for endoscopic ultrasound-guided fine-needle aspiration biopsy of solid pancreatic lesions in the absence of an onsite cytopathologist

Rei Suzuki; Atsushi Irisawa; Manoop S. Bhutani; Takuto Hikichi; Tadayuki Takagi; Ai Sato; Masaki Sato; Tsunehiko Ikeda; Ko Watanabe; Jun Nakamura; Kazuhiro Tasaki; Katsutoshi Obara; Hiromasa Ohira

Introduction:  A prior study with 22‐gauge needles recommended more than seven needle passes for endoscopic ultrasound‐guided fine‐needle aspiration biopsy (EUS‐FNA) of solid pancreatic lesions (SPL) without onsite cytopathology for optimal acquisition of cytopathological diagnosis. The feasibility of this recommendation should be re‐evaluated considering the later development and popularity of 25‐gauge EUS‐FNA needles. We aimed to determine the optimal number of needle passes for cytopathological specimen acquisition with 25‐gauge needles for EUS‐FNA of SPL.


Brain Pathology | 2012

Analysis of Chromosome 19q13.42 Amplification in Embryonal Brain Tumors with Ependymoblastic Multilayered Rosettes

Sumihito Nobusawa; Hideaki Yokoo; Junko Hirato; Akiyoshi Kakita; Hitoshi Takahashi; Takashi Sugino; Kazuhiro Tasaki; Hideaki Itoh; Tsutomu Hatori; Yoshie Shimoyama; Atsuko Nakazawa; Shigeru Nishizawa; Hiroshi Kishimoto; Keiko Matsuoka; Masahiro Nakayama; Naoki Okura; Yoichi Nakazato

Recently, it was reported that ependymoblastoma and embryonal tumor with abundant neuropil and true rosettes (ETANTR) show 19q13.42 amplification at a high frequency, suggesting that these tumors may constitute a single entity. As ependymoblastic rosettes are the most prominent features in both subtypes, embryonal tumor with multilayered rosettes (ETMR) was proposed, for which 19q13.42 amplification represents a specific molecular hallmark. However, ependymoblastic rosettes are not specific to ependymoblastoma and ETANTR, and are also found in a few other embryonal tumors as well as immature teratomas, and knowledge on 19q13.42 amplification in these tumors is limited. In this study, we performed fluorescence in situ hybridazation (FISH) analysis and differential polymerase chain reaction (PCR), and detected 19q13.42 amplification in three out of four ETANTR, one ependymoblastoma and one medulloepithelioma with ETANTR components, whereas none of the two atypical teratoid/rhabdoid tumors (AT/RT) with ependymoblastic rosettes nor two immature teratomas with developing neuroectodermal structures showed such amplification, suggesting that medulloepitheliomas would possibly be included in ETMR, and ependymoblastic rosettes in AT/RT do not signify that these tumors constitute ETMR. Also, we found C19MC rather than miR‐371‐373 was amplified in one ETANTR, suggesting that C19MC miRNA cluster seems to be more closely linked to the pathogenesis of ETMR.


Diagnostic Pathology | 2014

Radiological and pathological characteristics of giant cell tumor of bone treated with denosumab

Michiyuki Hakozaki; Takahiro Tajino; Hitoshi Yamada; Osamu Hasegawa; Kazuhiro Tasaki; Kazuo Watanabe; Shin-ichi Konno

We describe a case of giant cell tumor of the proximal tibia with skip bone metastases of the ipsilateral femur in a 20-year-old man. After the neoadjuvant treatment with denosumab, plain radiographs and computed tomography showed marked osteosclerosis and sclerotic rim formation, and 18F-FDG PET/CT showed a decreased standardized uptake value, whereas magnetic resonance imaging showed diffuse enhancement of the tumor, nearly the same findings as those at pretreatment. Pathological findings of the surgical specimen after the denosumab treatment showed benign fibrous histiocytoma-like features with complete disappearance of both mononuclear stromal cells and multinuclear osteoclast-like giant cells.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1090602085125068


International Journal of Oncology | 2011

Cathepsin L is highly expressed in gastrointestinal stromal tumors

Kohtaro Miyamoto; Manabu Iwadate; Yuka Yanagisawa; Emi Ito; Jun-ichi Imai; Masaya Yamamoto; Naoki Sawada; Motonobu Saito; Satoshi Suzuki; Izumi Nakamura; Shinji Ohki; Zenichiro Saze; Michihiko Kogure; Mitsukazu Gotoh; Κazutoshi Οbara; Hiromasa Ohira; Kazuhiro Tasaki; Masafumi Abe; Naoki Goshima; Shinya Watanabe; Satoshi Waguri; Seiichi Takenoshita

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract that are diagnosed by c-kit staining in most cases. A lysosomal cysteine proteinase termed cathepsin L has been commonly associated with malignancy in several cancer types, but this finding has not been reported for GISTs. We analyzed the cathepsin L mRNA and protein expression in GISTs. Real-time reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that cathepsin L levels were higher in GISTs than those in gastric or colorectal tumors; this finding was supported by results of the Western blot analysis. Immunohistochemistry revealed that cathepsin L was localized to the cytoplasm of GIST cells as an intense granular signal, which was not observed in the cells of leiomyoma, a mesenchymal tumor that was analyzed as a control specimen. Double immunofluorescence microscopy revealed that a portion of the granular signal colocalized with lysosome-associated membrane protein-1 (LAMP-1), which is a lysosomal marker. Moreover, immunohistochemical analysis of 43 tumor specimens revealed that 86.0% (n=37) were cathepsin-L positive, and this positivity was significantly correlated with c-kit positivity but not with other clinicopathological factors, including gender, age, region, size, mitosis and risk of recurrence. From these results, we conclude that cathepsin L is highly expressed in GISTs compared to its expression in other cancerous lesions; this identifies cathepsin-L as a new diagnostic marker for GISTs.


Pathology International | 1996

Analysis of lectin binding properties on human Burkitt's lymphoma cell lines that show high spontaneous metastasis to distant organs in SCID mice : The binding sites for soybean agglutinin lectin masked by sialylation are closely associated with metastatic lymphoma cells

Masafumi Abe; Osamu Suzuki; Kazuhiro Tasaki; Kunihiko Tominaga; Haruki Wakasa

Alterations in cell surface carbohydrates on human lymphoma cell lines with different spontaneous metastatic potential in the severe combined immunodeficiency (SCID) mouse model were analyzed. A difference In cell surface carbohydrates between high‐ (HBL‐2, HBL‐7 and HBL‐8) and no‐ or low‐(HBL‐4, HBL‐6, Daudi and Raji) spontaneous metastatic human lymphoma cell lines were analyzed on a FACScan using fluorescein‐isothiocyanate (FITC)‐conjugated lectins. The most consistent difference in lectin binding properties was found with soybean agglutinin (SBA) lectin. High‐metastatic lymphoma cells (HBL‐7 and HBL‐8 cells) in vitro were found to bind the SBA lectin, but the cells in vivo (in primary tumors and metastatic tumors of SCID mice) showed considerably reduced SBA lectin binding. In addition, HBL‐2 cells that almost did not bind SBA lectin in vitro and in vivo showed high spontaneous metastasis. Neuraminidase treatment revealed that SBA lectin binding sites were masked by sialic acid. On the other hand, no‐ or low‐metastatlc lymphoma cells in vitro and in vivo were found to bind SBA lectin. HBL‐8 cell clones without SBA lectin binding showed high spontaneous metastasis to distant organs in SCID mice but HBL‐8 cell clones with SBA lectin binding showed very low spontaneous metastasis. Sophora Japonica agglutinin (SJA) lectin is able to recognize the carbohydrates in common with SBA lectin, but it does not appear to be associated with metastatic capacity. These results suggest that the sialylation of particular carbohydrate residues on human lymphoma cells that are recognized by SBA lectin may be associated with the spontaneously metastatic capacity of human lymphoma cell lines in our SCID mouse model.


Pathology International | 2007

CD5-positive mucosa-associated lymphoid tissue (MALT) lymphoma of ocular adnexal origin: Usefulness of fluorescence in situ hybridization for distinction between mantle cell lymphoma and MALT lymphoma

Kazuhiro Tasaki; Akiko Shichishima; Minoru Furuta; Sayaka Yoshida; Naoya Nakamura; Masafumi Abe

Extranodal marginal zone B‐cell lymphoma of mucosa‐associated lymphoid tissue type (MALT lymphoma) usually lacks CD5 expression. Herein is described two cases of CD5‐positive MALT lymphoma of ocular adnexal origin. The differential diagnosis between CD5‐positive MALT lymphoma and mantle cell lymphoma (MCL), notably cyclin D1‐negative MCL, was difficult because both cases consisted histologically of small to medium‐sized cells with diffuse or vaguely nodular growth pattern, and the neoplastic cells were positive for CD5 and negative for cyclin D1. Somatic mutation analysis of the immunoglobulin heavy chain variable region (VH) gene in case 1 found a relatively higher mutation frequency (5.0%), which was not definitive to rule out MCL. Interphase fluorescence in situ hybridization (FISH) on paraffin‐embedded section using IgH/cyclin D1 (CCND1) probe showed that in both cases there was no molecular evidence of t(11;14), finally leading to the diagnosis of CD5‐positive MALT lymphoma. Although the present two patients had no recurrence over 34 months after initial diagnosis, careful observation is needed because the clinicopathological significance of MALT lymphoma with this rare phenotype remains obscure.


World Journal of Gastrointestinal Endoscopy | 2014

An automated spring-loaded needle for endoscopic ultrasound-guided abdominal paracentesis in cancer patients.

Rei Suzuki; Atsushi Irisawa; Manoop S. Bhutani; Takuto Hikichi; Tadayuki Takagi; Goro Shibukawa; Ai Sato; Masaki Sato; Tsunehiko Ikeda; Ko Watanabe; Jun Nakamura; Srinadh Annangi; Kazuhiro Tasaki; Katsutoshi Obara; Hiromasa Ohira

AIM To evaluate the feasibility of using an automated spring-loaded needle device for endoscopic ultrasound (EUS)-guided abdominal paracentesis (EUS-P) to see if this would make it easier to puncture the mobile and lax gastric wall for EUS-P. METHODS The EUS database and electronic medical records at Fukushima Medical University Hospital were searched from January 2001 to April 2011. Patients with a history of cancer and who underwent EUS-P using an automated spring-loaded needle device with a 22-gauge puncture needle were included. The needle was passed through the instrument channel and advanced through the gastrointestinal wall under EUS guidance into the echo-free space in the abdominal cavity and ascitic fluid was collected. The confirmed diagnosis of malignant ascites included positive cytology and results from careful clinical observation for at least 6 mo in patients with negative cytology. The technical success rate, cytology results and complications were evaluated. RESULTS We found 11 patients who underwent EUS-P with an automated spring-loaded needle device. In 4 cases, ascites was revealed only with EUS but not in other imaging modalities. EUS-P was done in 7 other cases because there was minimal ascitic fluid and no safe window for percutaneous abdominal aspiration. Ascitic fluid was obtained in all cases by EUS-P. The average amount aspirated was 14.1 mL (range 0.5-38 mL) and that was sent for cytological exam. The etiology of ascitic fluid was benign in 5 patients and malignant in 6. In all cases, ascitic fluid was obtained with the first needle pass. No procedure-related adverse effects occurred. CONCLUSION EUS-P with an automated spring-loaded needle device is a feasible and safe method for ascites evaluation.


Emergency Medicine Australasia | 2012

Case of scrub typhus complicated by severe disseminated intravascular coagulation and death

Yuko Ono; Yukihiro Ikegami; Kazuhiro Tasaki; Masahumi Abe; Choichiro Tase

Scrub typhus is an infectious disease that is caused by Orientia tsutsugamushi. The authors describe an autopsied case of scrub typhus complicated with severe disseminated intravascular coagulation (DIC). An 82‐year‐old man complained of fever 4 days after climbing a mountain. The patient was admitted to an urban hospital, and meropenem and ceftriaxone were administered. The patients condition deteriorated and he was transferred to a second hospital. On physical examination, a black scab was found and scrub typhus was suspected. Despite intensive treatment, the patient died on the fifth day. High levels of O. tsutsugamushi IgM antibody were confirmed. An autopsy revealed systemic vasculitis and perivasculitis. The endothelial tissue of the white pulp of the spleen was markedly infiltrated by plasma cells. The authors speculated that a severe immune reaction against O. tsutsugamushi enhanced an inflammatory response, leading to DIC. This case is a warning to doctors who are not familiar with scrub typhus.

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Masafumi Abe

Fukushima Medical University

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Haruki Wakasa

Fukushima Medical University

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Hiromasa Ohira

Fukushima Medical University

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Yuko Hashimoto

National Institutes of Health

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Kunihiko Tominaga

Fukushima Medical University

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Ai Sato

Fukushima Medical University

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Atsushi Irisawa

Fukushima Medical University

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Hiroshi Hojo

Fukushima Medical University

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Katsutoshi Obara

Fukushima Medical University

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