30 results on '"Atsushi Yamashita"'
Search Results
2. Non‐ampullary duodenal neoplasm of gastric phenotype showing multidirectional epithelial differentiation
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Kazunari Maekawa, Daisuke Kuroki, Takeomi Hamada, Ryoji Kushima, Yuichiro Sato, and Atsushi Yamashita
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General Medicine ,Pathology and Forensic Medicine - Published
- 2023
3. Underlying mechanisms of thrombus formation/growth in atherothrombosis and deep vein thrombosis
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Atsushi Yamashita and Yujiro Asada
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General Medicine ,Pathology and Forensic Medicine - Abstract
Thrombosis remains a leading cause of death worldwide despite technological advances in prevention, diagnosis, and treatment. The traditional view of arterial thrombus formation is that it is a platelet-dependent process, whereas that of venous thrombus formation is a coagulation-dependent process. Current pathological and basic studies on atherothrombosis and venous thrombosis have revealed the diverse participation of platelet and coagulation activation mechanisms in both thrombus initiation and growth processes during clinical thrombotic events. Atherosclerotic plaque cell-derived tissue factor contributes to fibrin formation and platelet aggregation. The degree of plaque disruption and a blood flow alteration promote atherothrombotic occlusion. While blood stasis/turbulent flow due to luminal stenosis itself initiates venous thrombus formation. The coagulation factor XI-driven propagation phase of blood coagulation plays a major role in venous thrombus growth, but a minor role in hemostasis. These lines of evidence indicate that atherothrombosis onset is affected by the thrombogenic potential of atherosclerotic plaques, the plaque disruption size, and an alteration in blood flow. Upon onset of venous thrombosis, enhancement of the propagation phase of blood coagulation under blood stasis and a hypercoagulable state contribute to large thrombus formation.
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- 2023
4. Surgical Management of Bilateral Venous Malformation (Cavernous Hemangiomas) of the Maxillary Sinus
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Takashi Anzai, Shin Ito, Atsushi Yamashita, Takuma Ide, Shori Tajima, Hiroko Okada, Fumihiko Matsumoto, and Katsuhisa Ikeda
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Otorhinolaryngology ,RF1-547 - Abstract
According to International Society for the Study of Vascular Anomalies classification 2018, “hemangioma” should be classified as either vascular tumor or vascular malformation (VM). So-called “cavernous hemangioma” is categorized as VM. VM rarely involves the mucous membranes of the sinonasal cavity and typically arises unilaterally from the sinonasal cavity. Bilateral VM of the maxillary sinus is extremely rare. To the best of our knowledge, there is no previous report of bilateral VM of the maxillary sinus. Here, we describe the surgical treatment of bilateral cavernous hemangiomas of the maxillary sinus. These tumors were successfully resected by endoscopic modified medial maxillectomy (EMMM) after embolization. Endoscopic sinus surgery, particularly EMMM, produces access to the bilateral maxillary sinus and can prevent several complications.
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- 2020
- Full Text
- View/download PDF
5. Ultralow Background Near‐Infrared Fluorophores with Dual‐Channel Intraoperative Imaging Capability
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Kai Bao, Molly Tully, Kevin Cardenas, Haoran Wang, Surbhi Srinivas, Jiyun Rho, Ok Hwa Jeon, Jason Dinh, Shinya Yokomizo, Rose McDonnell, Atsushi Yamashita, Satoshi Kashiwagi, Homan Kang, Hyun Koo Kim, and Hak Soo Choi
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Biomaterials ,Biomedical Engineering ,Pharmaceutical Science - Published
- 2023
6. Multiple asymptomatic coronary plaque ruptures and fissures in acute myocardial infarction
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Toshihiro Gi, Shun Nishino, Atsushi Yamashita, Nozomi Watanabe, Yoshisato Shibata, and Yujiro Asada
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Myocardial Infarction ,Humans ,Coronary Artery Disease ,General Medicine ,Coronary Vessels ,Plaque, Atherosclerotic ,Pathology and Forensic Medicine - Published
- 2022
7. Tissue factor expression and tumor‐infiltrating T lymphocytes in ovarian carcinomas and their association with venous thromboembolism
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Yujiro Asada, Yasuyuki Kawagoe, Yuichiro Sato, Aya Kuwahara, Murasaki Aman, Toshihiro Gi, Hiroshi Sameshima, Atsushi Yamashita, and Junji Onishi
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Endometriosis ,CD8-Positive T-Lymphocytes ,Thromboplastin ,Pathology and Forensic Medicine ,03 medical and health sciences ,Tissue factor ,Lymphocytes, Tumor-Infiltrating ,0302 clinical medicine ,medicine ,Carcinoma ,Humans ,cardiovascular diseases ,Aged ,Ovarian Neoplasms ,Membrane Glycoproteins ,Tumor-infiltrating lymphocytes ,business.industry ,Cancer ,Thrombosis ,Venous Thromboembolism ,General Medicine ,Middle Aged ,equipment and supplies ,medicine.disease ,P-Selectin ,030104 developmental biology ,Podoplanin ,030220 oncology & carcinogenesis ,Clear cell carcinoma ,Female ,Ovarian cancer ,business ,Carcinoma, Endometrioid ,Adenocarcinoma, Clear Cell - Abstract
Ovarian cancer is a known risk factor of venous thromboembolism (VTE). Thrombogenic factor expression and lymphocytic infiltrate have been reported in endometriosis and ovarian cancers. We reviewed 30 cases of ovarian carcinomas (high grade serous carcinoma, 10; endometrioid carcinoma, 10; clear cell carcinoma (CCC), 10) and 16 endometriotic lesions. We immunohistochemically investigated the expressions of tissue factor (TF), podoplanin, P-selectin, and number of CD4 and CD8 positive lymphocytes in cancer tissue and endometriotic lesions, along with their relationship with VTE. The expression of TF was higher in CCC. The TF expression and the number of CD8 positive cells were higher in cancer tissues with VTE than in those without VTE. The podoplanin or P-selectin expression did not differ among histological types or between cases with and without VTE. Our results demonstrated a high TF expression and intraepithelial CD8 cells in CCC, which were associated with VTE. The results suggest that infiltrating lymphocytes may affect TF expression that, in turn, influences VTE.
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- 2021
8. Pathophysiology of atherothrombosis: Mechanisms of thrombus formation on disrupted atherosclerotic plaques
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Kinta Hatakeyama, Atsushi Yamashita, Yujiro Asada, and Yuichiro Sato
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Thrombogenicity ,Review Article ,Fibrin ,Pathology and Forensic Medicine ,03 medical and health sciences ,Tissue factor ,0302 clinical medicine ,atherothrombosis ,medicine ,Animals ,Humans ,blood flow ,vasoconstriction ,Platelet ,coagulation factor ,cardiovascular diseases ,Thrombus ,platelet ,biology ,business.industry ,Thrombosis ,General Medicine ,Atherosclerosis ,medicine.disease ,Pathophysiology ,030104 developmental biology ,030220 oncology & carcinogenesis ,cardiovascular system ,biology.protein ,Hemorheology ,medicine.symptom ,business ,Vasoconstriction - Abstract
Atherothrombosis is a leading cause of cardiovascular mortality and morbidity worldwide. The underlying mechanisms of atherothrombosis comprise plaque disruption and subsequent thrombus formation. Arterial thrombi are thought to mainly comprise aggregated platelets as a result of high blood velocity. However, thrombi that develop on disrupted plaques comprise not only aggregated platelets, but also large amounts of fibrin, because plaques contain large amount of tissue factor that activate the coagulation cascade. Since not all thrombi grow large enough to occlude the vascular lumen, the propagation of thrombi is also critical in the onset of adverse vascular events. Various factors such as vascular wall thrombogenicity, local hemorheology, systemic thrombogenicity and fibrinolytic activity modulate thrombus formation and propagation. Although the activation mechanisms of platelets and the coagulation cascade have been intensively investigated, the underlying mechanisms of occlusive thrombus formation on disrupted plaques remain obscure. Pathological findings derived from humans and animal models of human atherothrombosis have uncovered pathophysiological processes during thrombus formation and propagation after plaque disruption, and novel factors have been identified that modulate the activation of platelets and the coagulation cascade. These findings have also provided insights into the development of novel drugs for atherothrombosis.
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- 2020
9. Ovarian Seromucinous Borderline Tumor and Clear Cell Carcinoma: An Unusual Combination
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Eriko Nakamura, Yuichiro Sato, Sayaka Moriguchi, Atsushi Yamashita, Takashi Higo, and Yujiro Asada
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Gynecology and obstetrics ,RG1-991 - Abstract
Ovarian seromucinous borderline tumors (SMBTs) are rare. They architecturally resemble serous borderline tumors but are much more frequently associated with endometriosis. The coexistence of other tumors with seromucinous tumors is also extremely rare. Here, we report an unusual combination of bilateral ovarian SMBT and clear cell carcinoma associated with polypoid endometriosis of the colon, in a 62-year-old woman. There was no transitional lesion between the two tumors. Immunohistochemistry showed different staining patterns in tumor components. Seromucinous tumor cells were positive for estrogen receptor (ER) and progesterone receptor (PgR) but negative for Napsin A, p504S, and HNF1B. Clear cell tumor cells were positive for Napsin A and p504S and focally positive for HNF1B but negative for ER and PgR. Loss of ARID1A expression was not observed in SMBTs, clear cell tumors, or endometriosis. These findings suggest that these tumors arose from separate endometriosis foci and collided within the same ovary. To the best of our knowledge, this is the first case of this unusual combination of ovarian seromucinous tumor and clear cell carcinoma to be reported in the English literature.
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- 2015
- Full Text
- View/download PDF
10. Optical Tissue Phantoms for Quantitative Evaluation of Surgical Imaging Devices
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Jason Dinh, Atsushi Yamashita, Homan Kang, Sylvain Gioux, and Hak Soo Choi
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General Medicine - Published
- 2022
11. Individual evaluation of cardiac marker expression and self-beating during cardiac differentiation of P19CL6 cells on different culture substrates
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Atsushi Mahara, Mitsuhi Hirata, Sachiro Kakinoki, Tetsuji Yamaoka, Akihisa Otaka, Takahiko Nakaoki, Takaaki Dan, Atsushi Yamashita, and Azizi Miskon
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0301 basic medicine ,Materials science ,Cardiac marker ,Cell Culture Techniques ,Biomedical Engineering ,Biomaterials ,03 medical and health sciences ,Cell Line, Tumor ,Gene expression ,Animals ,Myocytes, Cardiac ,Progenitor cell ,Troponin T ,biology ,GATA4 ,Troponin C type 1 ,Metals and Alloys ,Antigens, Differentiation ,Potassium channel ,Rats ,Cell biology ,Fibronectin ,030104 developmental biology ,cardiovascular system ,Ceramics and Composites ,biology.protein ,Myoblasts, Cardiac - Abstract
Cell-based therapies using self-beating cardiomyocytes have been attracting great attention for use in cardiac regeneration, although an effective procedure to improve cardiac differentiation and self-beating induction is required. The purpose of this study is to clarify the effect of the culture substrate on cardiac maturation by separately evaluating the cardiac differentiation step and the beating induction step in vitro. To this end, the well-studied cardiomyocyte-like progenitor cell line P19CL6 and neonatal cardiomyocytes (NCMs) were selected and cultured on substrates coated with collagen type I (Col-I), gelatin (Gel), fibronectin (FN), or poly-l-lysine (PLL). It was found that the cardiac differentiation step, which was assessed using cardiac marker gene expression (GATA-binding protein 4 (GATA4), myocyte-specific enhancer factor 2D (MEF2D), and hyperpolarization-activated cyclic nucleotide-gated potassium channel 4 (HCN4)) in the P19CL6 embryonal carcinoma cells, was greatly enhanced on Col-I, Gel, and PLL. In contrast, the spontaneous beating step, which was directly assessed by counting the beating colonies and measuring contractile protein gene expression (α-myosin heavy chain (α-MHC), troponin C type 1 (TnC1), and troponin T type 2 (TnT2)) in the rat NCMs, was enhanced on the FN and PLL surfaces. In the present study, for the first time, it was found that PLL enhances both the cardiac differentiation and the beating induction steps of cardiac maturation, which can aid in preparing beating cardiomyocytes for regenerative medicine. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1166-1174, 2017.
- Published
- 2017
12. Microvascular proliferation of brain metastases mimics glioblastomas in squash cytology
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Atsushi Yamashita, Yuichiro Sato, Toshihiro Gi, Yujiro Asada, S Sato, Takako Tokumitsu, Sayaka Moriguchi-Goto, and Hideo Takeshima
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Male ,0301 basic medicine ,medicine.medical_specialty ,Pathology ,Histology ,Cytodiagnosis ,Oligodendroglioma ,CD34 ,Antigens, CD34 ,Astrocytoma ,Pathology and Forensic Medicine ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Diffuse Astrocytoma ,Glioma ,Grade II Glioma ,medicine ,Humans ,neoplasms ,Cell Proliferation ,Pilocytic astrocytoma ,Brain Neoplasms ,business.industry ,Brain ,General Medicine ,Middle Aged ,medicine.disease ,Actins ,nervous system diseases ,Surgery ,030104 developmental biology ,030220 oncology & carcinogenesis ,Microvessels ,Female ,Glioblastoma ,business - Abstract
Objective Although microvascular proliferation is a key feature in the diagnosis of high-grade glioma, the characteristics of metastatic tumour vessels in smear preparations have not been documented. In this study, the vascular changes in metastatic brain tumours, using squash cytology to examine the vascular patterns in brain metastases, were reviewed. Methods One hundred and forty-three squash smears of brain tissue, including 25 normal or reactive tissue, 23 malignant lymphomas, 8 grade I glioma (pilocytic astrocytoma), 23 grade II glioma (diffuse astrocytoma and oligodendroglioma), 42 grade IV glioma (glioblastoma), and 22 metastasis, were assessed. Two vascular patterns were assessed: thick and branching, and glomeruloid. The vessel density, nuclear layer and the number of vessel branches were compared. Furthermore, tumour vessels of brain metastases were analysed by histology and for immunohistochemical expression of CD34, α-smooth muscle actin (SMA) and high-molecular-weight caldesmon (h-CD). Results Among 22 metastatic tumours, thick and branching vessels were found in 17 (77%) and glomeruloid vessels in 13 (59%). These incidences of microvascular proliferation patterns were similar to those of glioblastomas or pilocytic astrocytomas. Vessel density, nuclear layer and vessel wall branches were significantly higher in metastatic tumours than malignant lymphomas, grade II gliomas or normal brain tissues. Glomeruloid vessels consisted of CD34-positive cells and α-SMA-positive cells, and α-SMA-positive cells had a low h-CD expression. These immunohistochemical patterns were similar to those of high-grade gliomas. Conclusions The vascular features of metastatic brain tumours are similar to those of glioblastomas, suggesting that these microvascular proliferations contribute to the progression of metastatic tumours.
- Published
- 2016
13. Immunocytochemistry for Claudin-18 and Maspin in biliary brushing cytology increases the accuracy of diagnosing pancreatobiliary malignancies
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Atsushi Yamashita, Yuichiro Sato, Atsushi Nanashima, K Kondo, Yujiro Asada, Takako Tokumitsu, and Sayaka Moriguchi-Goto
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Adult ,Male ,medicine.medical_specialty ,Pathology ,Histology ,Immunocytochemistry ,Brushing cytology ,Adenocarcinoma ,Malignancy ,Sensitivity and Specificity ,Gastroenterology ,Pathology and Forensic Medicine ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Cytology ,Humans ,Medicine ,Claudin ,In Situ Hybridization, Fluorescence ,Serpins ,Aged ,Retrospective Studies ,Aged, 80 and over ,Pancreatic duct ,business.industry ,Brush cytology ,Pancreatic Ducts ,Maspin ,General Medicine ,Middle Aged ,medicine.disease ,Immunohistochemistry ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Bile Duct Neoplasms ,030220 oncology & carcinogenesis ,Claudins ,Female ,030211 gastroenterology & hepatology ,business - Abstract
Objective Biliary brush cytology is an important diagnostic tool in the evaluation of pancreatobiliary malignancies. However, it is difficult to distinguish between malignant and benign cells. The present study evaluated the utility of immunocytochemical expression of Claudin-18 and Maspin in brushing cytology specimens of pancreatobiliary lesions in the diagnosis of pancreatobiliary malignancies. Methods The study retrospectively assessed biliary and pancreatic duct brushing cytology specimens of 43 patients whose pancreatobiliary lesions were histologically diagnosed at the University of Miyazaki Hospital. Scanty cellularity slides and cases with no histological confirmation were excluded. Alcohol-fixed and Papanicolaou-stained slides were immunostained with monoclonal antibodies to Claudin-18 and Maspin. Results Of the 43 patients, 35 (81.4%) were finally histologically diagnosed with invasive adenocarcinomas. The sensitivity of routine cytology for the detection of malignancy was 63%, and the specificity was 100%. The sensitivity of cytology in combination with immunocytochemical expression of Claudin-18 (89%) or Claudin-18 and/or Maspin (97%) was significantly higher than that of cytology alone (P < 0.01). Conclusion Immunocytochemical staining for Claudin-18 and Maspin improved the diagnostic sensitivity for pancreatobiliary adenocarcinomas.
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- 2016
14. ALK,ROS1andNTRK3gene rearrangements in inflammatory myofibroblastic tumours
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Hidetaka Yamamoto, Kenichi Taguchi, Yui Hatanaka, Yoshinao Oda, Atsushi Yamashita, Akihiko Yoshida, Daisuke Mori, and Kenichi Kohashi
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Adult ,Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Histology ,Fibrosarcoma ,Biology ,Pathology and Forensic Medicine ,Neoplasms, Muscle Tissue ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Proto-Oncogene Proteins ,hemic and lymphatic diseases ,Biomarkers, Tumor ,medicine ,ROS1 ,Humans ,Anaplastic lymphoma kinase ,Anaplastic Lymphoma Kinase ,Oncogene Fusion ,Receptor, trkC ,Child ,Myofibroblasts ,Aged ,Gene Rearrangement ,Inflammation ,Proto-Oncogene Proteins c-ets ,Inflammatory myofibroblastic tumour ,Infant ,Receptor Protein-Tyrosine Kinases ,General Medicine ,Gene rearrangement ,Middle Aged ,Protein-Tyrosine Kinases ,medicine.disease ,Repressor Proteins ,ETV6 ,030104 developmental biology ,Fusion transcript ,Child, Preschool ,030220 oncology & carcinogenesis ,Cancer research ,Immunohistochemistry ,Female - Abstract
Aims The aim of this study was to elucidate the pathological features of inflammatory myofibroblastic tumour (IMT) with gene rearrangement other than ALK. Methods and results We investigated anaplastic lymphoma kinase (ALK), ROS1, ETV6, NTRK3 and RET in 36 cases of IMT by using immunohistochemical (IHC) staining, fluorescence in-situ hybridization, and reverse transcription polymerase chain reaction (RT-PCR). IHC staining showed ALK and ROS1 to be positive in 22 of 36 (61.1%) and two of 36 (5.6%) cases, respectively. In one case with ROS1 positivity, IHC staining showed cytoplasmic and dot-like ROS1 expression, and RT-PCR showed the presence of the TFG–ROS1 fusion transcript. Two cases of pulmonary IMT, in a 7-year-old patient and a 23-year-old patient, had ETV6 rearrangement, and the presence of the ETV6–NTRK3 fusion transcript was confirmed in one case. These tumours were composed of hypocellular myxoid areas and highly cellular areas with rich plasmacytic infiltration; the histological features were different from those of infantile fibrosarcoma. RET rearrangement was not detected. Conclusions These results suggest that a subset of ALK-negative IMTs have rearrangement of ROS1, ETV6 or NTRK3 as a possible oncogenic mechanism, and that the detection of these alterations may be of diagnostic value and helpful for determining promising therapeutic strategies.
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- 2016
15. Functional relationship between sphingomyelin synthase‐related protein and diacylglycerol kinase δ
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Atsushi Yamashita, Fumi Hoshino, Fumio Sakane, Chiaki Murakami, Hiromichi Sakai, and Yasuhiro Hayashi
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Functional Relationship ,biology ,Biochemistry ,Chemistry ,Sphingomyelin synthase ,Genetics ,biology.protein ,Molecular Biology ,Biotechnology ,Diacylglycerol kinase - Published
- 2020
16. Informative Three‐dimensional Survey of Cell/tissue Architectures in Thick Paraffin Sections by Simple Low‐vacuum Scanning Electron Microscopy
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Takeshi Kamimura, Fimiyo Aoyama, Nobuyasu Takahashi, Yujiro Asada, Akira Sawaguchi, Kaori Ichikawa, and Atsushi Yamashita
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Materials science ,Scanning electron microscope ,Cell ,medicine.disease ,Biochemistry ,Epithelium ,law.invention ,medicine.anatomical_structure ,Seminiferous tubule ,law ,Genetics ,medicine ,Glomerulus ,Thrombus ,Stem cell ,Electron microscope ,Molecular Biology ,Biotechnology ,Biomedical engineering - Abstract
Recent advances in bio-medical research, such as the production of regenerative organs from stem cells, require three-dimensional analysis of cell/tissue architectures. High-resolution imaging by electron microscopy is the best way to elucidate complex cell/tissue architectures, but the conventional method requires a skillful and time-consuming preparation. The present study developed a three-dimensional survey method for assessing cell/tissue architectures in 30-µm-thick paraffin sections by taking advantage of backscattered electron imaging in a low-vacuum scanning electron microscope. As a result, in the kidney, the podocytes and their processes were clearly observed to cover the glomerulus. The 30 µm thickness facilitated an investigation on face-side (instead of sectioned) images of the epithelium and endothelium, which are rarely seen within conventional thin sections. In the testis, differentiated spermatozoa were three-dimensionally assembled in the middle of the seminiferous tubule. Further application to vascular-injury thrombus formation revealed the distinctive networks of fibrin fibres and platelets, capturing the erythrocytes into the thrombus. The four-segmented BSE detector provided topographic bird’s-eye images that allowed a three-dimensional understanding of the cell/tissue architectures at the electron-microscopic level. Here, we describe the precise procedures of this imaging method and provide representative electron micrographs of normal rat organs, experimental thrombus formation, and three-dimensionally cultured tumour cells.
- Published
- 2018
17. Rehabilitation of biting abilities in patients with different types of dental prostheses
- Author
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Atsushi Yamashita, Yoshizo Matsuka, M. Morita, K. Miyaura, and T. Watanabe
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Rehabilitation ,Denture wearers ,Dentition ,business.industry ,medicine.medical_treatment ,Dentistry ,Masticatory force ,Bite force quotient ,Biting ,medicine ,In patient ,business ,General Dentistry ,Removable partial denture - Abstract
This study investigated the masticatory rehabilitation of subjects wearing different types of prostheses. Biting abilities per person (biting force, biting pressure and occlusal contact area) were assessed with a pressure detecting sheet (Prescale(R)). Five hundred and ninety volunteers were divided into four groups according to the type of posterior dentition: complete denture, removable partial denture, fixed partial denture, and full natural dentition groups. The biting forces of the fixed partial, removable partial and complete denture wearers were 80, 35 and 11% respectively, when expressed as a percentage of the subjects with a natural dentition. The complete denture wearers showed the highest biting pressure among the four groups, followed by the removable partial denture wearers. In a clinical intra-individual study, the biting abilities of 85 subjects, without (before insertion of) and with (after insertion of) renewed prostheses, were compared. No significant differences were found between biting before and immediately after insertion of the prostheses. However, the biting force and occlusal contact area increased 2 months after insertion of the prostheses. This study confirmed past clinical studies indicating an impaired masticatory function of denture wearers. The functional adaptation to new prostheses had improved at evaluation 2 months after insertion.
- Published
- 2008
18. Biomechanical calculation of human TM joint loading with jaw opening
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Yasushi Takenami, Takuo Kuboki, Kenji Maekawa, Glenn T. Clark, M. Shinoda, and Atsushi Yamashita
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Orthodontics ,Joint loading ,Materials science ,Jaw opening ,General Dentistry - Published
- 2008
19. Removal of adherent noise in images by using multiple cameras
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Toru Kaneko, Atsushi Yamashita, and Masayuki Kuramoto
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Noise ,Engineering ,business.industry ,Energy Engineering and Power Technology ,Computer vision ,Artificial intelligence ,Electrical and Electronic Engineering ,business - Abstract
In this paper, we propose a new method for removing view-disturbing noise from images taken with multiple cameras. In outdoor environments, scenes taken by cameras are often hard to see because of adherent noise on the surface of the lens-protecting glass. The proposed method analyzes multiple camera images describing the same scene, and synthesizes an image in which adherent noise is eliminated. We show the effectiveness of the proposed method through experimental results. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(3): 50–59, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20697
- Published
- 2008
20. Improved Cell Viability of Linear Polyethylenimine through γ-Cyclodextrin Inclusion for Effective Gene Delivery
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Tooru Ooya, Hidetaka Akita, Atsushi Yamashita, Hak Soo Choi, Hideyoshi Harashima, Kentaro Kogure, and Nobuhiko Yui
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Cell Survival ,Macromolecular Substances ,Gene delivery ,Transfection ,Biochemistry ,Mice ,chemistry.chemical_compound ,In vivo ,Gene expression ,Animals ,Polyethyleneimine ,Viability assay ,Cytotoxicity ,Molecular Biology ,Fluorescent Dyes ,Polyethylenimine ,Organic Chemistry ,Gene Transfer Techniques ,Biological Transport ,DNA ,Genetic Therapy ,Molecular biology ,chemistry ,NIH 3T3 Cells ,Biophysics ,Molecular Medicine ,Intracellular ,gamma-Cyclodextrins - Abstract
A polypseudorotaxane consisting of a linear polyethylenimine with Mn of 22,000 (LPEI22k) and gamma-cyclodextrins (gamma-CDs; LPEI22k/gamma-CD) has been examined as a gene carrier. The polyplex formation with luciferase-encoding plasmid DNA (pDNA), intracellular trafficking of polyplex, cytotoxicity, and transfection efficiency were evaluated by various characteristic methods. LPEI22k/gamma-CD formed a pDNA polyplex at higher N/P ratios than LPEI22k; this suggests that the gamma-CD threading sterically interfered with the polyplex formation. In addition, the zeta potentials of the polyplex significantly decreased due to the reduction in charge density of LPEI22k caused by gamma-CD threading. The cellular uptake of pDNA in the LPEI22k/gamma-CD polyplex was enhanced by free gamma-CDs released from the polyplex that might accelerate the cellular uptake through enhanced membrane affinity. LPEI22k/gamma-CD significantly increased cell viability even at high N/P ratios, and the polyplex showed high transfection efficacy. The low cytotoxicity and high gene expression of LPEI22k/gamma-CD are advantageous to polyplex administration in vivo.
- Published
- 2006
21. Atypical extraventricular neurocytoma
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Yujiro Asada, Atsushi Yamashita, Kazuki Nabeshima, Kousuke Marutsuka, Shinichiro Wakisaka, Sayaka Moriguchi, Shinichi Nakano, and Takumi Yoneyama
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Pathology ,medicine.medical_specialty ,biology ,Glial fibrillary acidic protein ,Brain tumor ,General Medicine ,medicine.disease ,Pathology and Forensic Medicine ,Lesion ,medicine.anatomical_structure ,medicine ,Atypia ,Synaptophysin ,biology.protein ,Neuropil ,Oligodendroglioma ,medicine.symptom ,Neurocytoma - Abstract
Extraventricular neurocytoma (EVN) is a rare brain tumor that poses diagnostic difficulty. Described herein is a case of atypical EVN arising in a 54-year-old woman. A well-circumscribed lesion (3.0 × 3.0 × 3.0 cm) in the right parietal lobe showed diffuse proliferation of monotonous tumor cells with perinuclear clearing within a delicate fibrillary matrix similar to neuropil. Tumor also showed vascular proliferation and high mitotic activity. Immunohistochemically, these tumor cells were strongly positive for synaptophysin both in the neuropil and in the perinuclear cytoplasm, and were negative for glial fibrillary acidic protein and Olig2. Ki-67 labeling index was 13.0% in the most stained areas, but accumulation of p53 was not observed. These findings were compatible with those of EVN with histological atypia. EVN should be considered as a candidate in the differential diagnosis of parenchymal brain tumor, especially oligodendroglioma. The important features are the delicate fibrillary matrix similar to neuropil, diffuse and strong immunoreactivity for synaptophysin, and negative immunoreactivity for Olig2. High proliferative activity without accumulation of p53 suggests that other factors are involved in oncogenesis of atypical EVN.
- Published
- 2006
22. Sunflower-Shaped Cyclodextrin-Conjugated Poly(ε-Lysine) Polyplex as a Controlled Intracellular Trafficking Device
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Kentaro Kogure, Hideyoshi Harashima, Hak Soo Choi, Hidetaka Akita, Rie Ito, Tooru Ooya, Atsushi Yamashita, and Nobuhiko Yui
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Lysine ,Conjugated system ,Transfection ,Models, Biological ,Biochemistry ,Cell Line ,Mice ,Animals ,Polylysine ,Molecular Biology ,chemistry.chemical_classification ,Cyclodextrins ,Molecular Structure ,Cyclodextrin ,Chemistry ,Organic Chemistry ,Biological Transport ,DNA ,Sunflower ,DNA metabolism ,Membrane ,NIH 3T3 Cells ,Biophysics ,Molecular Medicine ,Intracellular - Published
- 2005
23. Hemoglobin stimulates the expression of matrix metalloproteinases, MMP-2 and MMP-9 by synovial cells: A possible cause of joint damage after intra-articular hemorrhage
- Author
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Masugi Maruyama, E. Yoshida, Sayuri Ohmura, Takuya Tajima, Yasushi Tomitaka, Masahiko Sugiki, Atsushi Yamashita, and Yujiro Asada
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Cartilage, Articular ,Male ,musculoskeletal diseases ,medicine.medical_specialty ,Pathology ,Knee Joint ,Blotting, Western ,Gelatin Zymography ,Hemorrhage ,Matrix metalloproteinase ,Hemoglobins ,Western blot ,In vivo ,Internal medicine ,Synovial Fluid ,medicine ,Animals ,Humans ,Orthopedics and Sports Medicine ,Secretion ,Cells, Cultured ,biology ,medicine.diagnostic_test ,Chemistry ,Fibrinolysis ,Synovial Membrane ,Urokinase-Type Plasminogen Activator ,Enzyme Activation ,Endocrinology ,Matrix Metalloproteinase 9 ,Synovial Cell ,Proteoglycan ,biology.protein ,Matrix Metalloproteinase 2 ,Proteoglycans ,Rabbits ,Hemoglobin - Abstract
Intra-articular bleeding causes degradation of articular cartilage leading to joint disorders, but the mechanisms is not well understood. The present study examined the effect of hemoglobin on the ability of synovial tissues to produce plasminogen activators and matrix metalloproteinases that play important roles in the degradation of articular cartilage. Human Hb added to primary cultures of human knee synovial cells markedly increased fibrinolytic activity and gelatinolytic activity. The fibrinolytic activity was due to an increase in uPA activity. Western blot analysis and gelatin zymography indicated that the increased gelatinolytic activity was due to increased MMP-2 and -9. In order to know whether the effect of Hb on cultured synovial tissue is also true in in vivo system or not, rabbit hemoglobin was injected into rabbit knee joints. Coinciding with in vitro study, hemoglobin elicited considerable increase in fibrinolytic and gelatinolytic activity. The level of proteoglycan fragments in the hemoglobin-treated joint fluid was significantly elevated, indicating cartilage matrix degradation. Cartilage damage after hemoglobin treatment was also confirmed by histological study. These findings suggest that hemoglobin stimulates the secretion of uPA, MMP-2 and MMP-9 by synovial tissues, and raise a possible role of hemoglobin in joint damage after intra-articular bleeding.
- Published
- 2005
24. Quality of life assessment in patients with implant-supported and resin-bonded fixed prosthesis for bounded edentulous spaces
- Author
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Soichiro Okamoto, Hirofumi Yatani, Hidenori Suzuki, Manabu Kanyama, Atsushi Yamashita, Hikaru Arakawa, Wataru Sonoyama, and Takuo Kuboki
- Subjects
Fixed prosthesis ,Quality of life ,business.industry ,Prosthetic rehabilitation ,Bounded function ,Dentistry ,Medicine ,In patient ,Oral Surgery ,Self administered questionnaire ,business ,humanities ,Implant supported - Abstract
Objectives: Dental implants have become increasingly popular in the prosthetic rehabilitation of patients with bounded edentulous spaces. Oral condition-related quality of life (QOL) levels have rarely been assessed in these patients. Material and methods: Two groups of subjects with bounded edentulous spaces were studied: an implant-supported fixed prosthesis group (11 patients) and a resin-bonded fixed prosthesis group (33 patients). The two groups were well matched in terms of sex, age, missing units and location of missing units. The patients were requested to answer a self-administered QOL questionnaire with two major subscales − oral condition- and general condition-related QOL scores. The test–retest reliability of each question was pre-examined and found acceptable (mean Spearman rank correlation coefficient was 0.55 ± 0.16). Mean QOL score differences between the two groups were analyzed by the Mann–Whitney U-test. Results: Mean oral condition-related QOL scores of the implant-supported and resin-bonded fixed prosthesis groups were 87.8 ± 9.5 and 87.1 ± 12.3% (P = 0.85), and mean general condition-related QOL scores were 73.8 ± 14.8 and 71.6 ± 15.2% (P = 0.95), respectively. No significant QOL differences between the two groups were observed in the two subscales. Conclusion: In patients with bounded edentulous spaces, multidimensional QOL levels of patients with an implant-supported fixed prosthesis do not exceed those of patients with a resin-bonded fixed prosthesis in a short follow-up period.
- Published
- 2002
25. Analysis of the differentiation capacity of muscle satellite cells derived from FOXO1‐ genetically modified mice (1033.5)
- Author
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Sachika Ogawa, Ryoji Yoshimura, Yasutomi Kamei, Yusuke Ono, Yukino Hatazawa, and Atsushi Yamashita
- Subjects
Genetics ,FOXO1 ,Satellite (biology) ,Biology ,biology.organism_classification ,Molecular Biology ,Biochemistry ,Biotechnology ,Genetically modified organism ,Cell biology - Published
- 2014
26. Comparison of biting forces in different age and sex groups: a study of biting efficiency with mobile and non-mobile teeth
- Author
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Atsushi Yamashita, Yoshizo Matsuka, T. Watanabe, K. Miyaura, and M. Morita
- Subjects
Adult ,Male ,Adolescent ,Video Recording ,Descriptive survey ,Dentistry ,Age and sex ,Bite Force ,Sex Factors ,Occlusal contact ,stomatognathic system ,Sex factors ,parasitic diseases ,Image Processing, Computer-Assisted ,Pressure ,Humans ,Medicine ,General Dentistry ,Aged ,Aged, 80 and over ,business.industry ,Jaw, Edentulous, Partially ,Age Factors ,Middle Aged ,Bite force quotient ,stomatognathic diseases ,Biting ,Case-Control Studies ,Regression Analysis ,Female ,Tooth Mobility ,business ,Tooth ,Bit (key) - Abstract
This study aimed (1) to investigate the influences of sex, age and number of teeth on biting ability through a descriptive survey, and (2) to compare the biting ability between the subjects with and without mobile teeth in a case-control study. A total of 687 subjects cooperated in the descriptive survey. Each subject bit on a pressure detecting sheet with their maximum biting force. Three indices of biting ability: biting pressure (MPa), biting force (N) and occlusal contact area (mm2) were calculated from the impressed marks on the sheet using a high vision video processor system. These indices were correlated well with the number of teeth according to the multiple regression analysis. In the case-control study, matching procedures with sex, age and number of teeth were performed between the subjects with and without mobile teeth. No differences in the three indices were observed between the two well-balanced groups. The results showed that the number of teeth is most important to maintain biting ability, and that the presence of mobile teeth does not always reduce biting ability.
- Published
- 1999
27. Two Japanese cases of lichen planus pigmentosus-inversus
- Author
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Aki Kashima, Atsushi Yamashita, Yujiro Asada, Mitsuru Setoyama, and Akihiko Tajiri
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Anti-nuclear antibody ,Dermatology ,CD8-Positive T-Lymphocytes ,Asymptomatic ,Serology ,Antigens, CD1 ,Lymphocytic Infiltrate ,Dermis ,Hyperpigmentation ,Biopsy ,medicine ,Humans ,medicine.diagnostic_test ,business.industry ,Lichen Planus ,HLA-DR Antigens ,Middle Aged ,medicine.anatomical_structure ,Nail (anatomy) ,Female ,Liver function ,medicine.symptom ,business - Abstract
Case 1 was a 51-year-old Japanese woman. She presented with an asymptomatic brown macule located on the right axilla of 2 months' duration. The smooth macule was 2 cm in diameter with a sharp demarcation (Fig. 1A). Case 2 was a 62-year-old Japanese man. He presented with asymptomatic, symmetric, gray-brown macules located on the groin, axillae, and popliteal region of 6 months' duration. The smooth macules were several millimeters to centimeters in diameter and sharply demarcated (Fig. 1B). Oral or nail lesions, previous inflammatory processes in affected areas, and internal malignancies were absent. A causal relationship with drugs, recent sun exposure, or trauma could not be identified. Findings for work-up, including blood cell count, fasting blood sugar levels, liver function, serum electrolyte levels, serum electrophoresis, urinalysis, antinuclear antibodies, and serological examinations for human hepatitis viruses and syphilis, were within normal limits or negative. The lesions gradually disappeared without medication within 6 months. Biopsy specimens showed a lymphocytic infiltrate with basal vacuolar changes and prominent melanin incontinence in the upper dermis (Fig. 2A). The band-like lymphocytic infiltrate was moderate in Case 1 and mild in Case 2. Immunohistochemistry showed infiltrative CD8(+) T lymphocytes with keratinocytic damage, indicating cytotoxic injury of the keratinocytes (Fig. 2B). Both the epidermis and the upper dermis contained CD1a(+) cells (Fig. 2C). The keratinocytes focally and weakly expressed HLA-DR (Fig. 2D). These findings were identical in samples from both patients.
- Published
- 2007
28. The relationship between signs and symptoms of temporomandibular disorders and bilateral occlusal contact patterns during lateral excursions
- Author
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Atsushi Yamashita, Yoshizo Matsuka, Takuo Kuboki, Maria G. Orsini, Hirofumi Yatani, Shohei Terada, and E K Watanabe
- Subjects
Adult ,Male ,Dentistry ,Signs and symptoms ,Shoulder stiffness ,Palpation ,Tinnitus ,Occlusal contact ,Facial Pain ,Neck Muscles ,Humans ,Medicine ,General Dentistry ,medicine.diagnostic_test ,business.industry ,Dental occlusion ,Headache ,Temporomandibular Joint Disorders ,stomatognathic diseases ,Dental Occlusion, Traumatic ,Masticatory Muscles ,Laterality ,Vertigo ,Medial pterygoid muscle ,Female ,business ,Sternocleidomastoid muscle - Abstract
The relationship between signs and symptoms of temporomandibular disorders (TMD) and bilateral occlusal contact patterns was investigated in 143 TMD patients (mean age: 34.0 +/- 15.9 years; 38 male and 105 female). In addition to an interview regarding chief complaints and accompanying symptoms, various muscles and the temporomandibular joints were palpated bilaterally and occlusal analyses were made. Only 5 out of 108 paired variables were found to be significantly associated by using the chi-squared test. Medial pterygoid muscle pain on palpation showed significant associations with the occlusal contact pattern (P < 0.005), especially working side contacts (interocclusal tooth contacts on the working side) (P < 0.005), during contralateral excursions; sternocleidomastoid muscle pain on palpation showed a significant association with balancing side contacts (interocclusal tooth contacts on the balancing side) during ipsilateral excursions P < 0.05); shoulder stiffness and pain in the eye showed significant associations with balancing side contacts during contralateral excursions (P < 0.05). The results show only a weak relationship between some TMD symptomatology and bilateral occlusal contact patterns during lateral excursions. The findings suggesting the specific laterality of a few TMD signs and symptoms associated with particular occlusal contacts may deserve closer case-control study.
- Published
- 1998
29. Transacylase-Mediated and Phosphodiesterase-Mediated Synthesis ofN-Arachidonoylethanolamine, an Endogenous Cannabinoid-Receptor Ligand, in Rat Brain Microsomes
- Author
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Keizo Waku, Takashi Tonegawa, Takayuki Sugiura, Akihiro Sukagawa, Shinji Nakane, Atsushi Yamashita, Sachiko Kondo, and Yoshio Ishima
- Subjects
medicine.medical_treatment ,Phosphodiesterase ,Anandamide ,Ligand (biochemistry) ,Biochemistry ,Endocannabinoid system ,chemistry.chemical_compound ,chemistry ,N-Acylethanolamine ,medicine ,N-Acylphosphatidylethanolamine ,Arachidonic acid ,Cannabinoid - Abstract
The levels of N-arachidonoylethanolamine (anandamide), an endogenous cannabinoid-receptor ligand, and a relevant molecule, N-arachidonoylphosphatidylethanolamine (N-arachidonoylPtdEtn), in rat brain were investigated using a newly developed sensitive analytical method. We found that rat brain contains small but significant amounts of these two types of N-arachidonoyl lipids (4.3 pmol/g tissue and 50.2 pmol/g tissue, respectively). Then, we investigated how N-arachidonoylethanolamine (anandamide) is produced in the brain. We found that anandamide can be formed enzymatically via two separate synthetic pathways in the brain: enzymatic condensation of free arachidonic acid and ethanolamine; and formation of N-arachidonoylPtdEtn from PtdEtn and arachidonic acid esterified at the 1-position of phosphatidyl-choline (PtdCho), and subsequent release of anandamide from N-arachidonoylPtdEtn through the action of a phosphodiesterase. We confirmed that rat brain contains both the enzyme activities and lipid substrates involved in these reactions. Several lines of evidence strongly suggest that the second pathway, rather than the first one, meets the requirements and conditions for the synthesis of various species of N-acylethanolamine including anandamide in the brain.
- Published
- 1996
30. ChemInform Abstract: Facile Synthesis of Stereoisomers of the Non-Secosteroidal Ligand LG190178 and Their Evaluation Using the Mutant Vitamin D Receptor
- Author
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Shinobu Honzawa, Shigeaki Kato, Takayuki Sugiura, Atsushi Yamashita, Atsushi Kittaka, Masaaki Kurihara, Aki Nakatsu, Yukiko Sato, Haruhiro Okuda, and Yosuke Demizu
- Subjects
chemistry.chemical_compound ,chemistry ,Bisphenol ,Stereochemistry ,Reagent ,Mutant ,Glycidol ,Diastereomer ,General Medicine ,Ligand (biochemistry) ,Calcitriol receptor - Abstract
All four diastereomers of the non-secosteroidal ligand LG190178 are prepared by asymmetric reduction of bisphenol derivative (I) with chiral oxazaborolidine reagents followed by treatment with the corresponding glycidol derivatives, e.g. (III).
- Published
- 2011
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