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Two cases of primary small cell carcinoma of the stomach
Acta Medica Okayama , 2009,
Abstract: We report 2 cases of small cell carcinoma (SmCC) of the stomach with distant metastasis that were treated with the same chemotherapeutic regimens as used to treat small cell lung cancer. Although the mean survival of patients with SmCC of the stomach is reported to be only 7 months, our patients survived for 15 and 14 months, respectively. In our experience, these chemotherapeutic regimens might provide a survival benefit for patients with SmCC of the stomach, although they demonstrated no remarkable antitumor effects.
Diagnostic role of 18F-fluorodeoxyglucose positron emission tomography for follicular lymphoma with gastrointestinal involvement
Masaya Iwamuro,Hiroyuki Okada,Katsuyoshi Takata,Katsuji Shinagawa
World Journal of Gastroenterology , 2012, DOI: 10.3748/wjg.v18.i44.6427
Abstract: AIM: To investigate the capacity for 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) to evaluate patients with gastrointestinal lesions of follicular lymphoma. METHODS: This retrospective case series consisted of 41 patients with follicular lymphoma and gastrointestinal involvement who underwent 18F-FDG-PET and endoscopic evaluations at ten different institutions between November 1996 and October 2011. Data for endoscopic, radiological, and biological examinations performed were retrospectively reviewed from clinical records. A semi-quantitative analysis of 18F-FDG uptake was performed for each involved area by calculating the maximum standardized uptake value (SUVmax). Based on the positivity of 18F-FDG uptake in the gastrointestinal lesions analyzed, patients were subdivided into two groups. To identify potential predictive factors for 18F-FDG positivity, these two groups were compared with respect to gender, age at diagnosis of lymphoma, histopathological grade, pattern of follicular dendritic cells, mitotic rate, clinical stage, soluble interleukin-2 receptor levels detected by 18F-FDG-PET, lactate dehydrogenase (LDH) levels, hemoglobin levels, bone marrow involvement, detectability of gastrointestinal lesions by computed tomography (CT) scanning, and follicular lymphoma international prognostic index (FLIPI) risk. RESULTS: Involvement of follicular lymphoma in the stomach, duodenum, jejunum, ileum, cecum, colon, and rectum was identified in 1, 34, 6, 3, 2, 3, and 6 patients, respectively. No patient had esophageal involvement. In total, 19/41 (46.3%) patients exhibited true-positive 18F-FDG uptake in the lesions present in their gastrointestinal tract. In contrast, false-negative 18F-FDG uptake was detected in 24 patients (58.5%), while false-positive 18F-FDG uptake was detected in 5 patients (12.2%). In the former case, 2/19 patients had both 18F-FDG-positive lesions and 18F-FDG-negative lesions in the gastrointestinal tract. In patients with 18F-FDG avidity, the SUVmax value of the involved gastrointestinal tract ranged from 2.6 to 17.4 (median: 4.7). For the 18F-FDG-negative (n = 22) and -positive (n = 19) groups, there were no differences in the male to female ratios (10/12 vs 4/15, P = 0.186), patient age (63.6 ± 2.4 years vs 60.1 ± 2.6 years, P = 0.323), presence of histopathological grade 1 vs 2 (20/2 and 17/2, P = 1.000), follicular dendritic cell pattern (duodenal/nodal: 13/5 vs 10/3, P = 1.000), mitotic rate (low/partly high, 14/1 vs 10/3, P = 0.311), clinical stage according to the Ann Arbor system (stages IE and IIE/
Primary intestinal follicular lymphoma: How to identify follicular lymphoma by routine endoscopy
Masaya Iwamuro,Yoshinari Kawai,Katsuyoshi Takata,Seiji Kawano
World Journal of Gastrointestinal Endoscopy , 2013, DOI: 10.4253/wjge.v5.i1.34
Abstract: A 69-year-old Japanese female was diagnosed with primary intestinal follicular lymphoma. Esophagogastroduodenoscopy with high-definition imaging revealed not only the typical feature of whitish polyps of up to 2 mm in diameter in the duodenal second and third portions, but also more detailed morphology, such as enlarged whitish villi and tiny whitish depositions. These findings appeared to reflect the pathological structures; infiltration of lymphoma cells into the villi were probably seen as enlargement of the villi, and the formation of lymphoid follicles were shown as opaque white spots or tiny white depositions. Thus, the above features might contribute to the distinct diagnosis of intestinal follicular lymphoma. This case indicates that routine esophagogastroduodenoscopy can visualize microsurface structures, which can be pathognomonic and help to diagnose intestinal follicular lymphoma, even without magnifying endoscopy.
Endoscopic hemostasis for hemorrhage from an ileal diverticulum
Masaya Iwamuro,Mariko Hanada,Yoko Kominami,Reiji Higashi
World Journal of Gastrointestinal Endoscopy , 2011, DOI: 10.4253/wjge.v3.i7.154
Abstract: Hemorrhage from a non-Meckelian jejunoileal diverticulum is rare, and it is generally difficult to diagnose the source of the bleeding. Here, we report the case of a 59-year-old male with hemorrhage from an ileal diverticulum. Contrast computed tomography scans demonstrated the ileal diverticulum and extravasation of the contrast medium around it. The diagnosis was then made by computed tomography scans, and endoscopic mechanical hemostasis was performed under colonoscopy with three metal clips. The management of hemorrhage from jejunoileal diverticula is discussed.
A preliminary study for constructing a bioartificial liver device with induced pluripotent stem cell-derived hepatocytes
Iwamuro Masaya,Shiraha Hidenori,Nakaji Shuhei,Furutani Masumi
BioMedical Engineering OnLine , 2012, DOI: 10.1186/1475-925x-11-93
Abstract: Background Bioartificial liver systems, designed to support patients with liver failure, are composed of bioreactors and functional hepatocytes. Immunological rejection of the embedded hepatocytes by the host immune system is a serious concern that crucially degrades the performance of the device. Induced pluripotent stem (iPS) cells are considered a desirable source for bioartificial liver systems, because patient-derived iPS cells are free from immunological rejection. The purpose of this paper was to test the feasibility of a bioartificial liver system with iPS cell-derived hepatocyte-like cells. Methods Mouse iPS cells were differentiated into hepatocyte-like cells by a multi-step differentiation protocol via embryoid bodies and definitive endoderm. Differentiation of iPS cells was evaluated by morphology, PCR assay, and functional assays. iPS cell-derived hepatocyte-like cells were cultured in a bioreactor module with a pore size of 0.2 μm for 7 days. The amount of albumin secreted into the circulating medium was analyzed by ELISA. Additionally, after a 7-day culture in a bioreactor module, cells were observed by a scanning electron microscope. Results At the final stage of the differentiation program, iPS cells changed their morphology to a polygonal shape with two nucleoli and enriched cytoplasmic granules. Transmission electron microscope analysis revealed their polygonal shape, glycogen deposition in the cytoplasm, microvilli on their surfaces, and a duct-like arrangement. PCR analysis showed increased expression of albumin mRNA over the course of the differentiation program. Albumin and urea production was also observed. iPS-Heps culture in bioreactor modules showed the accumulation of albumin in the medium for up to 7 days. Scanning electron microscopy revealed the attachment of cell clusters to the hollow fibers of the module. These results indicated that iPS cells were differentiated into hepatocyte-like cells after culture for 7 days in a bioreactor module with a pore size of 0.2 μm. Conclusion We consider the combination of a bioreactor module with a 0.2-μm pore membrane and embedded hepatocytes differentiated from iPS cells to be a promising option for bioartificial liver systems. This paper provides the basic concept and preliminary data for an iPS cell-oriented bioartificial liver system. PACS code: 87. Biological and medical physics, 87.85.-d Biomedical engineering, 87.85.Lf Tissue engineering, 87.85.Tu Modeling biomedical systems.
Precursor B Lymphoblastic Lymphoma Involving the Stomach
Masaya Iwamuro,Yoshinari Kawai,Yasuhide Yamawaki,Katsuyoshi Takata,Kazuhide Yamamoto
Case Reports in Gastrointestinal Medicine , 2013, DOI: 10.1155/2013/930918
Abstract: Precursor B lymphoblastic lymphoma is a high-grade neoplasm arising from precursor lymphocytes of B-cell lineage. Extranodal sites such as the skin and bone are often involved, but gastrointestinal lesions of this disease are rarely encountered. Due to the infrequency, macroscopic forms of the gastrointestinal lesions have not been fully described. In this report, we present a case of precursor B lymphoblastic lymphoma involving the stomach, pancreas, bone, and bone marrow. Esophagogastroduodenoscopy showed multiple flat elevated lesions with irregular mucosa in the stomach. 1. Introduction Precursor B lymphoblastic lymphoma is a neoplasm of lymphoblasts committed to the B-cell lineage [1]. Histologically, neoplastic cells are composed of small- to medium-sized lymphoid cells with blastic nuclear chromatin and a high mitotic rate [2]. In immunohistochemical analysis, the disease is characterized by positive staining for terminal deoxynucleotidyl transferase (TdT), in addition to B-cell antigens [1]. Clinically, extranodal sites such as the skin and the bone are frequently affected. On the other hand, infiltration of the neoplastic cells into the gastrointestinal tract is relatively infrequent. Therefore, the endoscopic manifestation of this disease has not been fully revealed to date. We recently treated a patient with precursor B lymphoblastic lymphoma who had extensive extranodal involvement in the stomach, pancreas, bone, and bone marrow. Herein we report the case and illustrate its characteristic endoscopic features. 2. Case Presentation An 85-year-old Japanese female presented to Onomichi Municipal Hospital with facial pain and lockjaw due to a swelling of the left temporomandibular joint. Her pain had started one year previously. The patient went to another clinic at that time, but the cause of her symptoms was not revealed. Two months prior to her visit to our hospital, she went to a dental clinic because lockjaw had appeared. Subsequently, swelling of the temporomandibular joint worsened and she was referred to our hospital for further investigation and treatment. She had been taking antihypertensive agents for hypertension and antifungal agent for nail tinea of the feet. The patient had no previous history of hematopoietic or gastrointestinal diseases. Physical examination revealed no abnormalities except for a mass lesion in the left temporomandibular joint. There was no evidence of hepatosplenomegaly or peripheral lymphadenopathy. Laboratory findings revealed elevated levels of lactate dehydrogenase (LDH) to 232?IU/L (normal range:
Primary Follicular Lymphoma of the Duodenum with Erosions as Atypical Macroscopic Features
Keiko Takeuchi,Masaya Iwamuro,Atsushi Imagawa,Yoshitsugu Kubota,Katsuya Miyatani,Katsuyoshi Takata,Hiroyuki Okada
Case Reports in Medicine , 2012, DOI: 10.1155/2012/582607
Abstract: A 52-year-old Japanese woman who was eventually diagnosed with primary follicular lymphoma of the duodenum showed atypical endoscopic features, namely, erosions with peripheral whitish edematous mucosa. Initial biopsy specimens taken from the erosions revealed insufficient numbers of lymphoma cells for histological diagnosis. Subsequent biopsy specimens from the peripheral mucosa containing the whitish enlarged villi showed infiltration of the lymphoma cells forming lymphoid follicles, which led us to the appropriate diagnosis. This case indicates that endoscopists should take biopsy samples from the peripheral mucosa with whitish enlarged villi rather than erosions in the rare instances that erosions appear as the main macroscopic feature of intestinal follicular lymphoma.
Endoscopic features and prognoses of mantle cell lymphoma with gastrointestinal involvement
Masaya Iwamuro, Hiroyuki Okada, Yoshiro Kawahara, Katsuji Shinagawa, Toshiaki Morito, Tadashi Yoshino, Kazuhide Yamamoto
World Journal of Gastroenterology , 2010,
Abstract: AIM: To evaluate the endoscopic manifestations and prognoses of gastrointestinal (GI) mantle cell lymphoma (MCL).METHODS: A database search at the Department of Pathology of Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences revealed 57 MCL patients with GI involvement. Clinical records were available for 35 of the 57 patients from 21 institutions, and those 35 patients were enrolled in this study. We summarized the gross types of endoscopic features, event-free survival (EFS), and overall survival (OS) of those patients.RESULTS: Of the 35 patients, GI involvement in the esophagus, stomach, and duodenum was found in 2 (5.7%), 26 (74.3%), and 12 (34.3%) patients, respectively. Twenty-one of the 35 patients underwent colonoscopy; among them, GI involvement in the ileum, cecum, colon, and rectum was found in 10 (47.6%), 3 (14.3%), 12 (57.1%), and 10 (47.6%), respectively. Various lesions, such as superficial, protruded, fold thickening, or ulcerative, were found in the stomach, whereas multiple lymphomatous polyposis (MLP) was dominant from the duodenum to the rectum. Twelve patients were treated with a hyper-CVAD/MA regimen, and they had better OS (3-year rate, 88.3% vs 46.4%, P < 0.01) and better EFS (3-year rate, 66.7% vs 33.8%, P < 0.05) than the remaining 23 patients who were not treated with this regimen.CONCLUSION: MLP was a representative form of intestinal involvement, whereas a variety of lesions were found in the stomach. The hyper-CVAD/MA regimen may improve survival in these patients.
Numerical Study of Axial Magnetic Effects on a Turbulent Thermal Plasma Jet for Nanopowder Production Using 3D Time-Dependent Simulation  [PDF]
Masaya Shigeta
Journal of Flow Control, Measurement & Visualization (JFCMV) , 2018, DOI: 10.4236/jfcmv.2018.62010
Abstract: 3D time-dependent simulations are performed using a computational method suitable for thermal plasma flows to capture a turbulent field induced by a thermal plasma jet and steep gradients in nanopowder distributions. A mathematical model with a simple form is developed to describe effectively simultaneous processes of growth and transport of nanopowder in/around a thermal plasma flow. This growth-transport model obtains the spatial distributions of the number density and mean diameter of nanopowder with a lower computational cost. The results show that an argon thermal plasma jet induces multi-scale vortices even far from itself. A double-layer structure of high-temperature thicker vortex rings surrounded by low-temperature thinner vortex rings is generated in the upstream region. As the vortex rings flow downstream, the high-temperature thicker vortex rings deform largely whereas the low-temperature thinner vortex rings break up into smaller vortices. Nanopowder is generated at the fringe of plasma and transported widely outside the plasma region. The nanopowder grows up collectively by coagulation decreasing particle number as well as homogeneous nucleation and heterogeneous condensation. When a uniform magnetic field is applied in the axial direction, a longer and straighter thermal plasma jet is obtained because of Lorentz force and Joule heating. Larger nanopowder is produced around the plasma because turbulent diffusions of silicon vapor and nanoparticles by vortices are suppressed as well.
Loss of runt-related transcription factor 3 expression leads hepatocellular carcinoma cells to escape apoptosis
Yutaka Nakanishi, Hidenori Shiraha, Shin-ichi Nishina, Shigetomi Tanaka, Minoru Matsubara, Shigeru Horiguchi, Masaya Iwamuro, Nobuyuki Takaoka, Masayuki Uemura, Kenji Kuwaki, Hiroaki Hagihara, Junichi Toshimori, Hideki Ohnishi, Akinobu Takaki, Shinichiro Nakamura, Yoshiyuki Kobayashi, Kazuhiro Nouso, Takahito Yagi, Kazuhide Yamamoto
BMC Cancer , 2011, DOI: 10.1186/1471-2407-11-3
Abstract: RUNX3 expression was analyzed by immunoblot and immunohistochemistry in HCC cells and tissues, respectively. Hep3B cells, lacking endogenous RUNX3, were introduced with RUNX3 constructs. Cell proliferation was measured using the MTT assay and apoptosis was evaluated using DAPI staining. Apoptosis signaling was assessed by immunoblot analysis.RUNX3 protein expression was frequently inactivated in the HCC cell lines (91%) and tissues (90%). RUNX3 expression inhibited 90 ± 8% of cell growth at 72 h in serum starved Hep3B cells. Forty-eight hour serum starvation-induced apoptosis and the percentage of apoptotic cells reached 31 ± 4% and 4 ± 1% in RUNX3-expressing Hep3B and control cells, respectively. Apoptotic activity was increased by Bim expression and caspase-3 and caspase-9 activation.RUNX3 expression enhanced serum starvation-induced apoptosis in HCC cell lines. RUNX3 is deleted or weakly expressed in HCC, which leads to tumorigenesis by escaping apoptosis.Hepatocellular carcinoma (HCC)1 is the sixth most common cancer and responsible for more than half a million deaths worldwide each year [1-3]. Although most HCC cases occur in East Asia and Middle and West Africa, its incidence in some developed countries is increasing [1,4]. In most cases, HCC is fatal because of an incomplete understanding of the pathogenic mechanisms and inadequacies of early detection [1,5].The activation of proto-oncogenes plays a major role in the development of HCC [1,6-8], and a number of tumor suppressor genes may be associated with the development and progression of HCC [1,9-12]. Although several cancer-related genes are altered in HCC, the frequency of alterations for each individual gene is relatively low. In HCC, the alteration of tumor suppressor genes seems to be more important than that of oncogenes. Established genetic events include the loss of an allele, mutation, or promoter methylation [13-16]. A higher loss of heterozygosity (LOH) frequency was detected at several loci on c
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