16 results on '"Akihiro, Takiyama"'
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2. An Image Analyzing Method by a Homology Concept for Fracture Surfaces
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Akihiro Takiyama, Katsuyuki Kida, and Kazuaki Nakane
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General Engineering ,Calculus ,Geometry ,Homology (mathematics) ,Mathematics - Abstract
From early 20th, the homology have been studied as a branch of mathematics. It has been one of a major topic in mathematics and applied in many scientific fields. The homology can be regarded as a mathematical concept of quantifying the contact degree. Because it belongs to modern mathematics, advanced knowledge of mathematics are required to understand this concept. Fortunately, since the definition of the homology is very simple in two-dimensional case, we can easily apply this to image analyzing methods. Fracture surface is composed of a process that cracks grow. If these cracks contact one another, rupture occurs. Progress of the fracture would vary due to the effect of external force. We identify the rapid and the fatigue fracture surface by a homology method. By analyzing the state of fracture via a homology method, it is believed that the cause of fracture can be estimated.
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- 2015
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3. Persistent homology index as a robust quantitative measure of immunohistochemical scoring
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Akihiro Takiyama, Takashi Teramoto, Shinya Tanaka, Katsushige Yamashiro, and Hiroaki Suzuki
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0301 basic medicine ,Adult ,lcsh:Medicine ,Breast Neoplasms ,Computational biology ,Biology ,Homology (mathematics) ,Grayscale ,Article ,03 medical and health sciences ,0302 clinical medicine ,Biomarkers, Tumor ,Image Processing, Computer-Assisted ,Humans ,Nuclear atypia ,lcsh:Science ,Aged ,Aged, 80 and over ,Observer Variation ,Multidisciplinary ,Persistent homology ,lcsh:R ,Carcinoma, Ductal, Breast ,Explained sum of squares ,Middle Aged ,Immunohistochemistry ,Clinical Practice ,Quantitative measure ,030104 developmental biology ,030220 oncology & carcinogenesis ,lcsh:Q ,Female ,Algorithms - Abstract
Immunohistochemical data (IHC) plays an important role in clinical practice, and is typically gathered in a semi-quantitative fashion that relies on some degree of visual scoring. However, visual scoring by a pathologist is inherently subjective and manifests both intra-observer and inter-observer variability. In this study, we introduce a novel computer-aided quantification methodology for immunohistochemical scoring that uses the algebraic concept of persistent homology. Using 8 bit grayscale image data derived from 90 specimens of invasive ductal carcinoma of the breast, stained for the replicative marker Ki-67, we computed homology classes. These were then compared to nuclear grades and the Ki-67 labeling indices obtained by visual scoring. Three metrics for IHC staining were newly defined: Persistent Homology Index (PHI), center coordinates of positive and negative groups, and the sum of squares within groups (WSS). This study demonstrates that PHI, a novel index for immunohistochemical labeling using persistent homology, can produce highly similar data to that generated by a pathologist using visual evaluation. The potential benefits associated with our novel technology include both improved quantification and reproducibility. Since our method reflects cellularity and nuclear atypia, it carries a greater quantity of biologic data compared to conventional evaluation using Ki-67.
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- 2017
4. Hepatitis B virus reactivation presented at 10 months after the last R-CHOP therapy against malignant lymphoma: A case report
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Takeshi Matsui, Minoru Uebayashi, Toshiya Shinohara, Jong-Hon Kang, Seishou Ando, Akihiro Takiyama, Kunihiko Tsuji, Tamaki Ichiya, and Hiroyuki Maguchi
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Hepatitis B virus ,Malignant lymphoma ,Hepatology ,business.industry ,medicine ,medicine.disease_cause ,business ,Virology - Published
- 2013
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5. Pathology of frontotemporal dementia with limb girdle muscular dystrophy caused by a DNAJB6 mutation
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Hiromi Kanno, Hiroaki Yaguchi, Hidenao Sasaki, Hidehisa Takahashi, Masashi Watanabe, Ichiro Yabe, Mishie Tanino, Shigetsugu Hatakeyama, Yukiko K. Hayashi, Ikuko Takahashi, Huaying Cai, Shinya Tanaka, and Akihiro Takiyama
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Male ,Pathology ,medicine.medical_specialty ,Semantic dementia ,Nerve Tissue Proteins ,Disease ,LC-3 ,Aphasia ,mental disorders ,medicine ,Autophagy ,Dementia ,Humans ,Aged ,business.industry ,nutritional and metabolic diseases ,Brain ,General Medicine ,Frontotemporal lobar degeneration ,Motor neuron ,HSP40 Heat-Shock Proteins ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,nervous system diseases ,medicine.anatomical_structure ,Muscular Dystrophies, Limb-Girdle ,Mutation ,Surgery ,Neurology (clinical) ,Autopsy ,DNAJB6 ,Brain pathology ,medicine.symptom ,business ,Frontotemporal dementia ,Limb-girdle muscular dystrophy ,Molecular Chaperones - Abstract
Frontotemporal lobar degeneration (FTLD) is a heterogeneous roup of disorders characterized by disturbances of behavior nd personality and different types of language impairment with r without concomitant features of motor neuron disease or arkinsonism [1]. FTLD is classified into three categories: fronotemporal dementia (FTD), progressive non-fluent aphasia (PNFA), nd semantic dementia (SD) [2]. Moreover, FTD is classified into wo categories: pick type and motor neuron disease (MND) type. TLD is also classified into four neuropathological categories: TLD-tau pathology type, FTLD-TDP43 pathology type, FTLD-FUS athology type, and FTLD-other type [2]. Clinical FTD-Pick type is ssociated with FTLD-tau, TDP, or FUS, and some FTLD is caused by arious genetic mutations. Limb girdle muscular dystrophy (LGMD) is a progressive myopahy with necrosis and regenerative changes in skeletal muscle. GMD Type 1D is caused by mutations in the DNAJB6 (DnaJ homolog
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- 2014
6. Primary Mediastinal Liposarcoma, with 6 Years of Follow-up to Autopsy, Revealed Histopathological Features of Primary and Metastatic Lesions
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Akihiro Takiyama, Masaharu Nishimura, Nobuyuki Hizawa, K. Ito, Shinya Tanaka, Satoshi Konno, Jun Konishi, Satoshi Oizumi, Eiki Kikuchi, and Naofumi Shinagawa
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Male ,Pathology ,medicine.medical_specialty ,Metastatic lesions ,Mediastinal Liposarcoma ,business.industry ,medicine.medical_treatment ,Autopsy ,Liposarcoma ,General Medicine ,medicine.disease ,Debulking ,Mediastinal Neoplasms ,Primary tumor ,Metastasis ,body regions ,Radiation therapy ,Fatal Outcome ,Internal Medicine ,medicine ,Humans ,business ,Aged ,Follow-Up Studies - Abstract
Primary mediastinal liposarcoma was observed in a 73-year-old man. Because of tight adhesions to adjacent tissues, neither complete resection nor surgical debulking of the tumor was possible. A T-tube was inserted into the patient's trachea for severe dyspnea, and he was treated with radiotherapy and an oral peroxisome proliferator-activated receptor-gamma agonist. The patient died 6 years after the initial diagnosis. Autopsy revealed liposarcoma composed of 3 subtypes in the primary tumor: well-differentiated, dedifferentiated, and round cell components. Round cell and dedifferentiated liposarcomas were predominantly observed in the metastatic nodules.
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- 2010
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7. Sudden Death of a Patient with Pandemic Influenza (A/H1N1pdm) Virus Infection by Acute Respiratory Distress Syndrome
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Akihiro, Takiyama, Lei, Wang, Mishie, Tanino, Taichi, Kimura, Naoki, Kawagishi, Yasuyuki, Kunieda, Harutaka, Katano, Noriko, Nakajima, Hideki, Hasegawa, Tomoyuki, Takagi, Hiroshi, Nishihara, Tetsutaro, Sata, and Shinya, Tanaka
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Adult ,Microbiology (medical) ,Respiratory Distress Syndrome ,Reverse Transcriptase Polymerase Chain Reaction ,General Medicine ,Antiviral Agents ,Immunohistochemistry ,Death, Sudden ,Influenza A Virus, H1N1 Subtype ,Oseltamivir ,Infectious Diseases ,Japan ,Nasopharynx ,Influenza, Human ,Humans ,RNA, Viral ,Female ,Antigens, Viral ,Lung - Abstract
We describe an autopsy case of a patient with pandemic influenza (A/H1N1pdm) virus infection in Japan, who developed rapidly progressive viral pneumonia exhibiting diffuse alveolar damage. A 41-year-old female visited our hospital with a fever of 38.7C. She was a public health nurse with no underlying disease and had had contact with a group of elementary school students who had been infected with the influenza (A/H1N1pdm) virus 1 week earlier. She was prescribed oseltamivir and returned to the hotel where she was staying alone. The next day, she was found dead in her hotel room. At autopsy, both lungs were voluminous and microscopic examination revealed acute-stage, severe diffuse alveolar damage with remarkable mononuclear cell infiltration and hyaline membrane formation in the lungs. CD8-positive T lymphocytes were dominantly observed. Immunohistochemically, influenza A viral protein was confirmed in the damaged type II pneumocytes and also in the infiltrated macrophages. Real-time RT-PCR analysis of both pre- and post-mortem pharyngeal swabs confirmed a novel influenza (A/H1N1pdm) virus infection. This is the second autopsy case of influenza (A/H1N1pdm) virus infection in Japan, and the findings indicated that the patient died due to an exceptionally rapid progression of viral pneumonia. This case indicates that patients with influenza (A/H1N1pdm) virus infection should be carefully monitor for acute respiratory distress syndrome.
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- 2010
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8. A time-like surface in Minkowski 3-space which contains light-like lines
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Akihiro Takiyama and Shyuichi Izumiya
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Surface (mathematics) ,Simple (abstract algebra) ,Plane (geometry) ,Minkowski space ,Pseudosphere ,Geometry and Topology ,Space (mathematics) ,Mathematical physics ,Mathematics - Abstract
Simple characterizations of a pseudosphere or a time-like plane in Minkowski 3-space by the existence of light-like lines are given.
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- 1999
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9. A time-like surface in Minkowski 3-space which contains pseudocircles
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Shyuichi Izumiya and Akihiro Takiyama
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Physics ,Surface (mathematics) ,Simple (abstract algebra) ,Plane (geometry) ,General Mathematics ,Minkowski space ,Mathematical analysis ,Pseudosphere ,Computer Science::Computational Geometry ,Space (mathematics) - Abstract
Simple characterizations of a pseudosphere or a plane in Minkowski 3-space by the existence of pseudocircles are given.
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- 1997
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10. CNS lymphomatoid granulomatosis with lymph node and bone marrow involvements
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Akihiro, Takiyama, Hiroshi, Nishihara, Ukihide, Tateishi, Taichi, Kimura, Lei, Wang, Wang, Lei, Katsuji, Marukawa, Tomoo, Itoh, Satoshi, Hashino, Kazuo, Nagashima, and Shinya, Tanaka
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Male ,Pathology ,medicine.medical_specialty ,Cell Nucleus Shape ,Lymphomatoid granulomatosis ,T-Lymphocytes ,Central nervous system ,Gene Rearrangement, T-Lymphocyte ,Polymerase Chain Reaction ,Pathology and Forensic Medicine ,Bone Marrow ,medicine ,Humans ,Lymph node ,Polymorphism, Single-Stranded Conformational ,medicine.diagnostic_test ,business.industry ,Brain Neoplasms ,Brain biopsy ,Genes, T-Cell Receptor gamma ,Lymphoma, T-Cell, Peripheral ,Lymphomatoid Granulomatosis ,General Medicine ,Gene rearrangement ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Lymphoma ,medicine.anatomical_structure ,Neurology (clinical) ,Bone marrow ,Lymph Nodes ,business ,Infiltration (medical) - Abstract
Lymphomatoid granulomatosis (LYG) in the CNS is an uncommon lymphoproliferative disease with characteristic angiocentric lymphoreticular proliferative and granulomatous lesions exhibiting low-grade malignant potential. Here we report a rare case of CNS-LYG, which disseminated to the lymph node and bone marrow. A 50-year-old man was diagnosed with CNS-LYG based on brain biopsy showing perivascular infiltration of CD3-positive small T-lymphocytes without overt nuclear atypism. Eight months after the initial neurological symptoms, inguinal lymph node swelling was found and histopathologically diagnosed as peripheral T-cell lymphoma. TCRgamma-gene rearrangement study using both paraffin-embedded specimens of brain and inguinal lymph node demonstrated an identical clonal band. Considering the clinical course, we concluded lymph node involvement of CNS-LYG, suggesting the malignant potential of CNS-LYG.
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- 2008
11. [New characterization of the stereoscopic structure of proteins by using expanded Gauss mapping and total curvature]
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Akihiro, Takiyama
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Proto-Oncogene Proteins c-raf ,Viral Structural Proteins ,Hemoglobins ,Imaging, Three-Dimensional ,Normal Distribution ,ras Proteins ,Proteins - Published
- 2005
12. Chromophobe renal cell carcinoma with osteosarcoma-like differentiation
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Kanako Chikai, Akihiro Takiyama, Tomoo Itoh, Tomoko Nakagawa, Tomohiko Koyanagi, Takanori Yamashita, Gaku Mouri, Satoshi Ota, Shin Suzuki, Nobuo Shinohara, and Kazuo Nagashima
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Male ,Pathology ,medicine.medical_specialty ,Chromophobe Renal Cell Carcinoma ,Vimentin ,Chromophobe cell ,Pathology and Forensic Medicine ,Cytokeratin ,Fatal Outcome ,Renal cell carcinoma ,Metaplasia ,medicine ,Carcinoma ,Humans ,Carcinoma, Renal Cell ,Aged ,Kidney ,Osteosarcoma ,biology ,business.industry ,medicine.disease ,Kidney Neoplasms ,medicine.anatomical_structure ,Cell Transformation, Neoplastic ,biology.protein ,Surgery ,Anatomy ,medicine.symptom ,business - Abstract
Sarcomatoid differentiation in renal cell carcinoma is thought to be the result of the dedifferentiation of the parent tumor, and it can be found in the chromophobe renal cell carcinoma just as other subtypes. We report a case of chromophobe renal cell carcinoma, which showed osteosarcoma-like differentiation. This is the first known case ever to be clearly identified as such. The patient was a 74-year-old man, and the CT scan revealed a huge retroperitoneal mass, which protruded from the lower half of the kidney and directly invaded the colon. Intraabdominal dissemination and metastases to the liver and lungs were also found. The resected tumor histologically showed sarcoma-like spindle cell proliferation and partly produced massive osteoid, which simulated the osteosarcoma. In addition, a typical histology of chromophobe renal cell carcinoma was found in part of the tumor. Immunohistochemically, spindle cells were reactive for epithelial membrane antigen, cytokeratin, and vimentin. The cell nests that were labeled by epithelial membrane antigen and cytokeratin were also found in the osteosarcoma-like area. We think that these phenomena were the result of "dedifferentiation" and metaplasia of the chromophobe renal cell carcinoma.
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- 2002
13. REPLY
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Hiroshi Nishihara, Shinya Tanaka, and Akihiro Takiyama
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Letter to the editor ,business.industry ,Medicine ,Neurology (clinical) ,General Medicine ,business ,Classics ,Pathology and Forensic Medicine - Published
- 2010
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14. Corrigendum
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Hiroshi Nishihara, Shinya Tanaka, W. Lei, Tamio Itoh, Takashi Kimura, Katsuji Marukawa, Kazuo Nagashima, Satoshi Hashino, Akihiro Takiyama, and Ukihide Tateishi
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Pathology ,medicine.medical_specialty ,medicine.anatomical_structure ,Cns lymphomatoid granulomatosis ,business.industry ,medicine ,Neurology (clinical) ,General Medicine ,Bone marrow ,Neuropathology ,business ,Lymph node ,Pathology and Forensic Medicine - Published
- 2009
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15. Homology-based method for detecting regions of interest in colonic digital images.
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Kazuaki Nakane, Akihiro Takiyama, Seiji Mori, and Nariaki Matsuura
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CANCER research , *HOMOLOGY (Biochemistry) , *CANCER cells , *COLON cancer , *IMAGE analysis , *PATHOLOGY - Abstract
Background: A region of interest (ROI) is a part of tissue that contains important information for diagnosis. To use many image analysis methods efficiently, a technique that would allow for ROI identification is required. For the colon, ROIs are characterized by areas of stronger color intensity of hematoxylin. Since malignant tumors grow in the innermost layer, most ROIs will be located in the colonic mucosa and will be an accumulation of tumor cells and/or integrated cells with distorted architecture. Methods: Using homology theory, our group proposed a method to estimate the contact degree of elements in a unit area of tissue. Homology is a concept that is used in many branches of algebra and topology, and it can quantify the contact degree. Due to the lack of contact inhibition of cancer cells, an area with unusual contact degree is expected to be a potential ROI. Results: The current work verifies the accuracy of this method against the results of pathological diagnosis, based on 1825 colonic images provided by the Osaka Medical Center for Cancer and Cardiovascular Diseases. Although we have many false positives and there is a possibility of missing undifferentiated types of cancer, this system is very effective for detecting ROIs. Conclusions: The mathematical system proposed by our group successfully detects ROIs and is a potentially useful tool for differentiating tumor areas in microscopic examination very quickly. Because we use only the information from low-power field images, there is room for further improvement. This system could be used to screen for not only colon cancer but other cancers as well. More sophisticated and more efficient automated pathological diagnosis systems can be developed by integrating various techniques available today. [ABSTRACT FROM AUTHOR]
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- 2015
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16. Pathology of frontotemporal dementia with limb girdle muscular dystrophy caused by a DNAJB6 mutation.
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Ichiro Yabe, Mishie Tanin, Hiroaki Yaguchi, Akihiro Takiyama, Huaying Cai, Hiromi Kanno, Ikuko Takahashi, Yukiko K. Hayashi, Masashi Watanabe, Hidehisa Takahashi, Shigetsugu Hatakeyama, Shinya Tanaka, and Hidenao Sasaki
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FRONTOTEMPORAL dementia , *MUSCULAR dystrophy , *GENETIC mutation , *CONSERVED sequences (Genetics) , *AUTOPHAGY , *CLINICAL medicine research , *NEUROLOGY - Published
- 2014
- Full Text
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