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Dive into the research topics where Akemi Takamizawa is active.

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Featured researches published by Akemi Takamizawa.


American Journal of Pathology | 1998

Smoke Extract Stimulates Lung Epithelial Cells to Release Neutrophil and Monocyte Chemotactic Activity

Takeshi Masubuchi; Sekiya Koyama; Etsuro Sato; Akemi Takamizawa; Keishi Kubo; Morie Sekiguchi; Sonoko Nagai; Takateru Izumi

Inflammatory cells accumulate within the lungs of cigarette smokers. Current concepts suggest that these cells can induce protease-antiprotease and/or oxidant-antioxidant imbalance(s), which may damage the normal lung alveolar and interstitial structures. Because type II pneumocytes line the alveolar space, and because the inflammatory cells migrate and reside at the alveolus, we postulated that the type II pneumocytes might release chemotactic activity for neutrophils and monocytes in response to smoke extract. To test this hypothesis, A549 cells were cultured and the supernatant fluids were evaluated for the neutrophil and monocyte chemotactic activity (NCA and MCA) by a blind-well chamber technique. A549 cells released NCA and MCA in response to smoke extract in a dose- and time-dependent manner (P < 0.05). Checkerboard analysis showed that the activity was chemotactic. Partial characterization of NCA and MCA revealed that the activity was partly heat labile, trypsin sensitive, and ethyl acetate extractable. Lipoxygenase inhibitors and cycloheximide inhibited the release of NCA and MCA. Molecular sieve column chromatography showed multiple peaks for both NCA and MCA. NCA was inhibited by anti-human-interleukin (IL)-8 antibody, granulocyte colony-stimulating factor (G-CSF) antibody, or leukotriene (LT)B4 receptor antagonist. Monocyte chemoattractant protein (MCP)-1 antibody or LTB4 receptor antagonist inhibited MCA. Immunoreactive IL-8, G-CSF, MCP-1, and LTB4 significantly increased in the supernatant fluids in response to smoke extract. These data suggest that the type II pneumocytes may release NCA and MCA and modulate the inflammatory cell recruitment into the lung.


American Journal of Clinical Oncology | 2002

Chemotherapy for advanced thymic carcinoma: clinical response to cisplatin, doxorubicin, vincristine, and cyclophosphamide (ADOC chemotherapy).

Thomonobu Koizumi; Yasuki Takabayashi; Satoshi Yamagishi; Kenji Tsushima; Akemi Takamizawa; Akihiro Tsukadaira; Hiroshi Yamamoto; Yoshitaka Yamazaki; Shinji Yamaguchi; Keisaku Fujimoto; Keishi Kubo; Yoshiki Hirose; Jirou Hirayama; Hisanori Saegusa

The role of systemic chemotherapy and optimal regimen in thymic carcinoma remains uncertain. We evaluated the clinical responsiveness of ADOC (cisplatin, doxorubicin, vincristine, and cyclophosphamide) chemotherapy for advanced thymic carcinoma that have distant metastatic or unresectable lesions. From 1996 to 2000, we treated eight cases of thymic carcinoma. According to the classification by Masaoka et al., the clinical stage in one case was IVa, whereas the others were IVb. Histologic subtypes were as follows: four cases were squamous cell carcinoma, two cases were undifferentiated, and two were small-cell carcinoma. All patients received 50 mg/m2 of cisplatin and 40 mg/m2 of doxorubicin intravenously on day 1, 0.6 mg/m2 of vincristine intravenously on day 3, and 700 mg/m2 of cyclophosphamide intravenously on day 4, ADOC regimen, respectively, at 3- to 4-week intervals. Six patients obtained a partial response after ADOC chemotherapy and the overall clinical response rate was 75%. There were no life-threatening side effects noted. Cisplatin plus VP-16 chemotherapy (PVP) was performed in three cases before the ADOC regimen, but PVP chemotherapy did not show beneficial effects in two patients. Median survival time was 19 months. ADOC chemotherapy appears to have significant activity against thymic carcinoma.


Respirology | 2006

Hypoxia-sensitive molecules may modulate the development of atherosclerosis in sleep apnoea syndrome

Motonori Hayashi; Keisaku Fujimoto; Kazuhisa Urushibata; Akemi Takamizawa; Osamu Kinoshita; Keishi Kubo

Objectives:  Obstructive sleep apnoea hypopnoea syndrome (OSAHS) is associated with increased morbidity and mortality due to cardiovascular disease. In order to examine the association between OSAHS and cardiovascular disease, this study measured hypoxia‐inducible and atherosclerosis‐associated molecules in the peripheral blood.


American Journal of Physiology-lung Cellular and Molecular Physiology | 1999

Smoke extract stimulates lung fibroblasts to release neutrophil and monocyte chemotactic activities.

Etsuro Sato; Sekiya Koyama; Akemi Takamizawa; Takeshi Masubuchi; Keishi Kubo; Richard A. Robbins; Sonoko Nagai; Takateru Izumi

Accumulation of monocytes and neutrophils and fibrous distortion of the airway are characteristics of airway disease secondary to smoking. The presence of inflammatory cells and fibrosis correlate, and, therefore, we postulated that lung fibroblasts might release chemotactic activity for neutrophils and monocytes in response to smoke extract. To test this hypothesis, human fetal lung (HFL1) fibroblasts were cultured, and the supernatant fluid was evaluated for neutrophil (NCA) and monocyte (MCA) chemotactic activities with a blind well chamber technique. HFL1 fibroblasts released chemotactic activity in response to smoke extract in a dose- and time-dependent manner (P < 0.05). Checkerboard analysis showed that the activity was predominantly chemotactic. Partial characterization of the released chemotactic activity revealed that the activity was partly heat labile, trypsin sensitive, and ethyl acetate extractable. Lipoxygenase inhibitors and cycloheximide inhibited the release of both NCA and MCA. Molecular-sieve chromatography revealed that NCA and MCA were heterogeneous. NCA was inhibited by anti-human interleukin (IL)-8 and anti-granulocyte colony-stimulating factor antibodies and a leukotriene (LT) B(4)-receptor antagonist. Anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) and anti-monocyte chemoattractant protein (MCP)-1 antibodies and an LTB(4)-receptor antagonist inhibited MCA. Immunoreactive IL-8, granulocyte colony-stimulating factor, GM-CSF, and MCP-1 significantly increased in culture supernatant fluid in response to smoke extract. Finally, smoke extract augmented the expression of mRNAs of IL-8, GM-CSF, and MCP-1. These data demonstrate that lung fibroblasts release NCA and MCA in response to smoke extract and suggest that lung fibroblasts may modulate the inflammatory cell recruitment into the lung.


American Journal of Physiology-lung Cellular and Molecular Physiology | 1998

Alveolar type II-like cells release G-CSF as neutrophil chemotactic activity

Sekiya Koyama; Etsuro Sato; Takeshi Masubuchi; Akemi Takamizawa; Keishi Kubo; Sonoko Nagai; Takateru Izumi

We evaluated the potential of A549 cells, an alveolar type II epithelial cell line, to release granulocyte colony-stimulating factor (G-CSF), in addition to interleukin (IL)-8 and leukotriene B4, as neutrophil chemotactic activity (NCA). Human recombinant IL-1β stimulated A549 cells to release NCA in a time- and dose-dependent fashion. The released NCA was blocked by mouse anti-human G-CSF polyclonal antibody. Molecular-sieve column chromatography revealed that IL-1β induced the release of a 19- to 20-kDa chemotactic mass that was inhibited by anti-human G-CSF antibody. IL-1β stimulated the release of G-CSF in a dose-dependent fashion, but the time-dependent profile of G-CSF showed that the concentration of G-CSF declined after 48 h. Tumor necrosis factor (TNF)-α, Escherichia coli lipopolysaccharide (LPS), and bradykinin (BK) stimulated A549 cells to release NCA that was inhibited by anti-G-CSF antibody. The release of G-CSF in response to TNF-α, LPS, and BK was significantly increased. The similar concentrations of human recombinant G-CSF (10-1,000 pg/ml) as in the supernatant fluid induced neutrophil chemotaxis. G-CSF mRNA was expressed time and dose dependently at 4 h and declined after 4 h in response to IL-1β as evaluated by RT-PCR. The expression of G-CSF mRNA was also observed by TNF-α, LPS, and BK stimulation. These data suggest that type II alveolar epithelial cells may produce G-CSF as NCA and may participate in the regulation of leukocyte extravasation.We evaluated the potential of A549 cells, an alveolar type II epithelial cell line, to release granulocyte colony-stimulating factor (G-CSF), in addition to interleukin (IL)-8 and leukotriene B4, as neutrophil chemotactic activity (NCA). Human recombinant IL-1beta stimulated A549 cells to release NCA in a time- and dose-dependent fashion. The released NCA was blocked by mouse anti-human G-CSF polyclonal antibody. Molecular-sieve column chromatography revealed that IL-1beta induced the release of a 19- to 20-kDa chemotactic mass that was inhibited by anti-human G-CSF antibody. IL-1beta stimulated the release of G-CSF in a dose-dependent fashion, but the time-dependent profile of G-CSF showed that the concentration of G-CSF declined after 48 h. Tumor necrosis factor (TNF)-alpha, Escherichia coli lipopolysaccharide (LPS), and bradykinin (BK) stimulated A549 cells to release NCA that was inhibited by anti-G-CSF antibody. The release of G-CSF in response to TNF-alpha, LPS, and BK was significantly increased. The similar concentrations of human recombinant G-CSF (10-1,000 pg/ml) as in the supernatant fluid induced neutrophil chemotaxis. G-CSF mRNA was expressed time and dose dependently at 4 h and declined after 4 h in response to IL-1beta as evaluated by RT-PCR. The expression of G-CSF mRNA was also observed by TNF-alpha, LPS, and BK stimulation. These data suggest that type II alveolar epithelial cells may produce G-CSF as NCA and may participate in the regulation of leukocyte extravasation.


American Journal of Physiology-lung Cellular and Molecular Physiology | 1998

Human lung fibroblasts release chemokinetic activity for monocytes constitutively

Sekiya Koyama; Etsuro Sato; Tsuyoshi Masubuchi; Akemi Takamizawa; Hiroshi Nomura; Keishi Kubo; Sonoko Nagai; Takateru Izumi

We determined whether human lung fibroblasts (HLFs) might release mediators that are responsible for monocyte chemokinetic activity (MCA) constitutively. HLF supernatant fluids showed MCA in a time-dependent manner (P < 0.001). Checkerboard analysis of 24- and 72-h supernatant fluids showed that the activity was chemokinetic. Partial characterization of 24- and 72-h supernatant fluids revealed that the mediators released after 24 h were predominantly composed of lipid-soluble activity, and MCA was blocked by lipoxygenase inhibitors. The mediators released after 72 h were predominantly trypsin sensitive and blocked by cycloheximide. Molecular-sieve column chromatography identified four peaks of MCA. A polyclonal antibody to monocyte chemoattractant protein-1 (MCP-1) inhibited MCA by 20% after 24 h and by 40% after 72 h. Granulocyte-macrophage colony-stimulating factor (GM-CSF) and transforming growth factor-beta (TGF-beta) antibodies attenuated MCA released after 72 h by 30 and 10%, respectively. These antibodies inhibited corresponding molecular-weight peaks separated by molecular-sieve column. The concentrations of MCP-1, GM-CSF, and TGF-beta were 4,698 +/- 242, 26.8 +/- 3.8, and 550 +/- 15 pg/ml, respectively. A leukotriene B4 (LTB4)-receptor antagonist attenuated the total MCA and the lowest molecular weight peak of MCA. The concentrations of LTB4 were 153.4 +/- 12.4 (24 h) and 212 +/- 16.6 (72 h) pg/ml. These findings suggest that HLFs may modulate the recruitment of monocytes into the lung by releasing MCP-1, GM-CSF, TGF-beta, and LTB4 constitutively.We determined whether human lung fibroblasts (HLFs) might release mediators that are responsible for monocyte chemokinetic activity (MCA) constitutively. HLF supernatant fluids showed MCA in a time-dependent manner ( P < 0.001). Checkerboard analysis of 24- and 72-h supernatant fluids showed that the activity was chemokinetic. Partial characterization of 24- and 72-h supernatant fluids revealed that the mediators released after 24 h were predominantly composed of lipid-soluble activity, and MCA was blocked by lipoxygenase inhibitors. The mediators released after 72 h were predominantly trypsin sensitive and blocked by cycloheximide. Molecular-sieve column chromatography identified four peaks of MCA. A polyclonal antibody to monocyte chemoattractant protein-1 (MCP-1) inhibited MCA by 20% after 24 h and by 40% after 72 h. Granulocyte-macrophage colony-stimulating factor (GM-CSF) and transforming growth factor-β (TGF-β) antibodies attenuated MCA released after 72 h by 30 and 10%, respectively. These antibodies inhibited corresponding molecular-weight peaks separated by molecular-sieve column. The concentrations of MCP-1, GM-CSF, and TGF-β were 4,698 ± 242, 26.8 ± 3.8, and 550 ± 15 pg/ml, respectively. A leukotriene B4(LTB4)-receptor antagonist attenuated the total MCA and the lowest molecular weight peak of MCA. The concentrations of LTB4 were 153.4 ± 12.4 (24 h) and 212 ± 16.6 (72 h) pg/ml. These findings suggest that HLFs may modulate the recruitment of monocytes into the lung by releasing MCP-1, GM-CSF, TGF-β, and LTB4 constitutively.


Experimental Lung Research | 2003

Methotrexate stimulates lung epithelial cells to release inflammatory cell chemotactic activities.

Sekiya Koyama; Etsuro Sato; Akemi Takamizawa; Akihiro Tsukadaira; Masayuki Haniuda; Makoto Kurai; Hiroki Numanami; Sonoko Nagai; Takateru Izumi

Methotrexate-induced pneumonitis has been reported as an infrequent but potentially serious complication of therapy in a variety of malignant and benignconditions. Because inflammatorycell infiltration is concerned with the development of methotrexate-induced pneumoinitis, and because airway epithelial cells participate in the orchestration of lung inflammation, the authors determined whether methotrexate might stimulate airway epithelial cells (A549 cells) to release neutrophil, monocyte, and eosinophil chemotactic activities (NCA, MCA, and ECA). A549 cells released NCA, MCA, and ECA in a dose- and time-dependent manner in response to methotrexate. Partial characterization revealed the heterogeneity of NCA, MCA, and ECA. The release of chemotactic activity was blocked by lipoxygenase inhibitors and cycloheximide. NCA was inhibited by leukotriene (LT) B 4 receptor antagonist, and anti-interleukin (IL)-8 and granulocyte colony-stimulatingfactor (G-CSF) antibodies. MCA was attenuated by LTB 4 receptor antagonist, and anti-monocyte chemoattractant protein (MCP)-1 and granulocyte-macrophage CSF (GM-CSF) antibodies. ECA was attenuated by LTB 4 receptor antagonist, and anti-IL-8 and GM-CSF antibodies. The release of IL-8, G-CSF, MCP-1, GM-CSF, and LTB 4 from A549 cells significantly increased in response to methotrexate. The mRNA expression of IL-8 and MCP-1 was augmented by methotrexate stimulation. These data suggest that type II epithelial cells may modulate inflammatory cell recruitment into the lung by releasing NCA, MCA, and ECA in response to methotrexate.


American Journal of Physiology-lung Cellular and Molecular Physiology | 1999

Bleomycin stimulates lung epithelial cells to release neutrophil and monocyte chemotactic activities.

Etsuro Sato; Sekiya Koyama; Takeshi Masubuchi; Akemi Takamizawa; Keishi Kubo; Sonoko Nagai; Takateru Izumi

Although bleomycin, an antineoplastic drug, is used in the treatment of a variety of tumors, the mechanisms of bleomycin-induced lung injury and fibrosis are not fully elucidated. We postulated that bleomycin might stimulate A549 cells, a type II pneumocyte cell line, to release neutrophil and monocyte chemotactic activities (NCA and MCA, respectively). To test this hypothesis, A549 cell supernatant fluids were harvested and evaluated for NCA and MCA. A549 cell supernatant fluids showed NCA and MCA in response to bleomycin in a dose- and time-dependent manner (P < 0.05). Checkerboard analysis revealed that both NCA and MCA were predominantly chemotactic. Partial characterization of the released NCA and MCA showed that the activities were partially heat labile, trypsin digested, and predominantly ethyl acetate extractable. Lipoxygenase inhibitors and cycloheximide inhibited the release of chemotactic activities significantly. Molecular-sieve column chromatography revealed that the released activities were heterogeneous. However, low-molecular-weight activity was prominent. Leukotriene B4-receptor antagonist, anti-interleukin-8, anti-granulocyte colony-stimulating factor, and anti-monocyte chemoattractant protein-1 antibodies attenuated the chemotactic activities. Immunoreactive leukotriene B4 receptor, interleukin-8, granulocyte colony-stimulating factor, and monocyte chemoattractant protein-1 significantly increased in supernatant fluids in response to bleomycin. These data demonstrate that bleomycin stimulates type II epithelial cells to release chemotactic activities and plays a role in inflammatory cell recruitment into the lung.


Respiration | 2004

Primary Malignant Lymphoma in the Posterior Mediastinum

Akemi Takamizawa; Tomonobu Koizumi; Keisaku Fujimoto; Keishi Kubo; Y. Maruyama; Satoshi Kawakami; Takayuki Honda

We present a case of primary malignant lymphoma arising from the posterior mediastinum. A 63-year-old woman was admitted to our hospital for further examination of her chest radiographic findings. She was asymptomatic. Chest computed tomography (CT) and magnetic resonance imaging (MRI) showed a posterior mediastinal mass in the right thoracic paravertebral region. A percutaneous needle biopsy was performed under CT. The histological findings with immunochemical staining revealed a B cell type of diffuse malignant lymphoma. 67Ga scintigraphy revealed accumulation in this area, suggesting the posterior mediastinum as the origin of the disease. Reports of primary malignant lymphoma in the posterior mediastinum are extremely rare. The radiographic characteristics are discussed.


The Journal of the Japanese Society of Clinical Cytology | 2000

Cutaneous nocardiosis in the chest wall effectively diagnosed by needle aspirate. A case report.

Jun Kanemoto; Emiko Nakamura; Kyoichi Miyagawa; Toshio Shimizu; Akemi Takamizawa; Kenji Kawaguchp

背景:穿刺吸引細胞診が有用であった, 本邦でもまれな胸部皮下ノカルジア症の1例について報告する.症例:症例は79歳男性, 検診にて尿蛋白を指摘, ネフローゼ症候群の疑いで当院を受診した.ステロイド剤による治療を開始したが, 開始後7ヵ月頃から, 右前腕の疹痛と側胸部皮下に6cm大の腫瘤が出現した.診断目的のため, 穿刺吸引細胞診を施行したところ好中球, リンパ球, マクロファージ, 変性壊死物質に混じって繊細な糸状の菌糸が認められた.菌糸はPAS染色, Grocott染色, Gram染色, Ziehl-Neelsen染色 (Fite法) 陽性を示しNocardiaが強く疑われた.細菌培養の結果からNocardia faroinioaと確認された.結論:ステロイド剤や免疫抑制剤, 抗がん剤治療を受けている患者に膿瘍中に繊細な菌糸が認められた場合, ノカルジア症である可能性も考慮すべきである.

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