158 results on '"Kazunori Kato"'
Search Results
2. Development of an In-House EphA2 ELISA for Human Serum and Measurement of Circulating Levels of EphA2 in Hypertensive Patients with Renal Dysfunction
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Maki Murakoshi, Takumi Iwasawa, Takeo Koshida, Yusuke Suzuki, Tomohito Gohda, and Kazunori Kato
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biomarker ,hypertension ,chronic kidney disease ,eGFR ,EphA2 ,Medicine (General) ,R5-920 - Abstract
Identifying novel biomarkers of kidney function in patients with chronic kidney disease (CKD) has strong clinical value as current measures have limitations. This study aims to develop and validate a sensitive and specific ephrin type-A receptor 2 (EphA2) enzyme-linked immunosorbent assay (ELISA) for human serum, and determine whether its results correlate with traditional renal measures in patients with hypertension. The novel ELISA of the current study was validated and used to measure circulating EphA2 levels in 80 hypertensive patients with and without kidney function decline (eGFR less than 60 mL/min/1.73 m2). Validation of the EphA2 ELISA showed good recovery (87%) and linearity (103%) and no cross-reactivity with other Eph receptors. Patients with kidney function decline had lower diastolic blood pressure, and higher UPCR and EphA2 than those without kidney function decline. The association of age and eGFR with EphA2 was maintained in the stepwise multiple regression analysis. In a multivariate logistic model, EphA2 was associated with a lower eGFR (2) after adjustment for age, sex, and UPCR. High circulating EphA2 levels have potential application as a clinical biomarker for the presence of CKD in patients with hypertension.
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- 2022
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3. Habitual cigarette smoking attenuates shear‐mediated dilation in the brachial artery but not in the carotid artery in young adults
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Kazuya Suzuki, Takuro Washio, Shingo Tsukamoto, Kazunori Kato, Erika Iwamoto, and Shigehiko Ogoh
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endothelial function ,internal carotid artery ,nitric oxide ,reactive oxygen species ,shear rate ,Physiology ,QP1-981 - Abstract
Abstract In the present study, we hypothesized that habitual cigarette smoking attenuates endothelial function in the cerebral circulation as well as that of the peripheral circulation in young adults. To test this hypothesis, we measured cerebrovascular and peripheral flow‐mediated dilation (FMD) in young smokers and nonsmokers in the present study. Ten healthy nonsmokers and 10 smokers participated in the study. We measured blood velocity and diameter in the brachial artery and internal carotid artery (ICA) using Doppler ultrasound. We identified shear‐mediated dilation in the brachial artery and ICA by the percentage change in peak diameter during hyperemia stimulation (reactive hyperemia and hypercapnia). We measured the baseline diameter and the shear rate area under the curve from the onset of hyperemia to peak dilation in the brachial artery and ICA, finding the measurements of the smokers and those of the nonsmokers did not differ (p > .05). In contrast to brachial FMD (5.07 ± 1.79% vs. 7.92 ± 3.01%; smokers vs. nonsmokers, p = .019), FMD in the ICA was not attenuated in the smokers compared with that of the nonsmokers (5.46 ± 2.32% vs. 4.57 ± 2.70%; p = .442). These findings indicate that in young healthy smokers, cerebral endothelial function was preserved, and the response of cerebral endothelial function to smoking was different from that of peripheral vasculature.
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- 2020
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4. NK Cells Can Preferentially Target Prostate Cancer Stem-like Cells via the TRAIL/DR5 Signaling Pathway
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Taiga Seki, Yui Shimizu, Kyota Ishii, Yuzuki Takahama, Kazunori Kato, and Tomohiro Yano
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androgen-dependent prostate cancer ,stem cells ,NK cells ,cytotoxicity ,TRAIL/DR5 signal pathway ,Microbiology ,QR1-502 - Abstract
Background: The occurrence of androgen-dependent prostate cancer mainly depends on prostate cancer stem cells. To reduce the risk of androgen-dependent prostate cancer, the direct elimination of prostate cancer stem cells is important, but an elimination strategy has not yet been established. A previous study showed that natural killer (NK) cells can preferentially target cancer stem cells in several solid tumors except prostate cancer. In this context, this study was undertaken to investigate if NK cells can selectively attack androgen-dependent prostate cancer stem cells. Methods: Prostate cancer stem-like cells were separated from an androgen-dependent prostate cancer cell line (LNCaP) using a three-dimensional culture system. LNCaP stem-like cells or LNCaP cells were co-cultured with human NK cells (KHYG-1) for 24–72 h, and cell viability was determined using the WST-8 method. The expression of each protein in the cell membrane was evaluated through FACS analysis, and mRNA levels were determined using real-time PCR. Results: KHYG-1 cells had more potent cytotoxicity against LNCaP stem-like cells than LNCaP cells, and the potency of the cytotoxicity was strongly related to the TRAIL/DR5 cell death pathway. Conclusion: NK cells can preferentially target prostate cancer stem-like cells via the TRAIL/DR5 pathway.
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- 2021
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5. Trapping and proliferation of target cells on C60 fullerene nano fibres
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Seiki Iwai, Shunji Kurosu, Hideki Sasaki, Kazunori Kato, and Toru Maekawa
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Nanotechnology ,Materials science ,Biotechnology ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
The ratio of the surface area to the volume of materials increases in inverse proportion to their size and therefore the surface area of nanostructures and nanomaterials is extremely large compared to that of macroscopic materials of the same volume, thanks to which it is supposed that chemical and biochemical reactions may be greatly enhanced and target molecules and cells may be efficiently trapped on the surface of nanomaterials. It is well known that C60 molecules are stable both physically and chemically and the affinity of C60 molecules with biomolecules is rather high. Here, we synthesise fibres composed of C60 and sulphur and immobilise the surface of the fibres with the primary antibody; i.e., epithelial cell adhesion molecules (anti-EpCAM), to trap target cells. The primary antibody is evenly immobilised on the fibres confirmed by a fluorescent secondary antibody attached to the primary one and then TE2 esophageal and DLD-1 colon cancer cells are successfully trapped by the primary antibody immobilised on the fibres thanks to its high affinity with TE2 and DLD-1 cells, whereas few IM9 B lymphoblast cells are captured on the fibres since the affinity of the primary antibody with IM9 cells is extremely low. Furthermore, those cells trapped by the primary antibody immobilised on the fibres proliferate faster than native cells thanks to the primary antibody acting as a growth factor. The present result suggests that different types of cells can be trapped and grown on nano fibres by immobilising appropriate antibody molecules on the surface of the fibres. Even an extremely small number of cells in sample fluids may be analysed and characterised for the detection of diseases such as cancer in the early stage by trapping and proliferating target cells on the fibres.
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- 2017
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6. Diagnostic Technique for Deterioration Inspection of Metallic Products through the In situ Measurement Using a Thermophysical Handy Tester
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Kazunori KATO and Ichiro TAKAHASHI
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deterioration inspection ,in situ measurement ,non-destructive inspection ,thermophysical handy tester ,thermal conductivity ,Mechanical engineering and machinery ,TJ1-1570 ,Mechanics of engineering. Applied mechanics ,TA349-359 - Abstract
This paper proposes a non-destructive technique using a thermophysical handy tester to inspect the deterioration of metallic products. In the early stage of fatigue in a metallic body, many micro-cracks appear on the surface of the stressed body. As fatigue progresses, these micro-cracks multiply and grow, while the apparent thermal conductivity of the surface layer spontaneously decreases. This phenomenon introduces the possibility of determining the progress of deterioration through in situ measurement of thermophysical properties. To estimate the degree of deterioration of materials, a dimensionless deterioration factor α is introduced. In order to corroborate this technique, several fatigue tests using carbon steels were conducted herein. Throughout the tests, apparent thermal conductivities and deterioration factors up to the limit of fatigue were periodically measured using a thermophysical handy tester. Furthermore, microscopic observations to investigate the evolution of micro-cracks were performed for stage-assessment during the period of fatigue tests. The results clearly demonstrate that this technique is useful for the non-destructive diagnosis of such deterioration.
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- 2010
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7. Elicitation of both anti HIV-1 Env humoral and cellular immunities by replicating vaccinia prime Sendai virus boost regimen and boosting by CD40Lm.
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Xianfeng Zhang, Tomoyoshi Sobue, Mao Isshiki, Shun-ichi Makino, Makoto Inoue, Kazunori Kato, Tatsuo Shioda, Takashi Ohashi, Hirotaka Sato, Jun Komano, Hideji Hanabusa, and Hisatoshi Shida
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Medicine ,Science - Abstract
For protection from HIV-1 infection, a vaccine should elicit both humoral and cell-mediated immune responses. A novel vaccine regimen and adjuvant that induce high levels of HIV-1 Env-specific T cell and antibody (Ab) responses was developed in this study. The prime-boost regimen that used combinations of replication-competent vaccinia LC16m8Δ (m8Δ) and Sendai virus (SeV) vectors expressing HIV-1 Env efficiently produced both Env-specific CD8(+) T cells and anti-Env antibodies, including neutralizing antibodies (nAbs). These results sharply contrast with vaccine regimens that prime with an Env expressing plasmid and boost with the m8Δ or SeV vector that mainly elicited cellular immunities. Moreover, co-priming with combinations of m8Δs expressing Env or a membrane-bound human CD40 ligand mutant (CD40Lm) enhanced Env-specific CD8(+) T cell production, but not anti-Env antibody production. In contrast, priming with an m8Δ that coexpresses CD40Lm and Env elicited more anti-Env Abs with higher avidity, but did not promote T cell responses. These results suggest that the m8Δ prime/SeV boost regimen in conjunction with CD40Lm expression could be used as an immunization platform for driving both potent cellular and humoral immunities against pathogens such as HIV-1.
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- 2012
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8. Novel [111In]In-BnDTPA-EphA2-230-1 Antibody for Single-Photon Emission Computed Tomography Imaging Tracer Targeting of EphA2
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Takenori Furukawa, Hiroyuki Kimura, Minon Sasaki, Takumu Yamada, Takumi Iwasawa, Yusuke Yagi, Kazunori Kato, and Hiroyuki Yasui
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General Chemical Engineering ,General Chemistry - Published
- 2023
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9. Abstract 5958: Analysis of MDSCs as a diagnostic and therapeutic target for gastric cancer
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Suguru Yamauchi, Takumi Iwasawa, Tomoaki Ito, Malcom V. Brock, Tetsu Fukunaga, Hajime Orita, and Kazunori Kato
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Cancer Research ,Oncology - Abstract
Background: Gastric cancer (GC) is the second most common cancer in Japan in terms of incidence and the third most common in terms of deaths. The onset and progression of cancer are generally suppressed by the action of immune cells, which is an inflammatory response. MDSCs are thought to promote cancer progression and invasion by suppressing the function of immune cells, making them potential therapeutic and diagnostic targets. We measured MDSCs in GC patients and observed more monocyte-derived MDSCs in peripheral blood in advanced GC than in early GC. However, granulocyte-derived MDSCs showed no difference in GC progression when markers for classical MDSCs were used. We considered that granulocyte-derived MDSCs were much more abundant than monocyte-derived MDSCs in peripheral blood and were involved in cancer progression. We hypothesized that we had a new granulocyte-derived marker for advanced GC that did not show differences in classical markers, but may have different functions, and aimed to identify a novel subset that may be a therapeutic and diagnostic target. Method: For GC patients, we used heparin blood samples provided by patients who consented to Juntendo University. We analyzed the expression of various cell surface proteins against populations of CD33high, CD66bhigh, and HLA-DRlow as classical markers of MDSCs derived from granulocytes of GC patients using FACS (Melody). MDSCs were isolated by a cell sorter and used for experiments such as RNA-Seq. Novel markers and involved cytokines were quantified in plasma components by cytometric bead array. Result: The chemokine receptors CCR2, CCR5, CXCR4, and CXCR5 were highly expressed in MDSCs of advanced GC patients. The ability to suppress T-cell activation was also found to be stronger in MDSCs with advanced GC. In addition, IL-10 produced by MDSCs was also more abundant in the plasma of patients with advanced GC, as well as chemokines according to chemokine receptors. Conclusion: The high expression of chemokine receptors on MDSCs in advanced GC may indicate that chemokines produced at the cancer site facilitate the migration of MDSCs. These novel subsets of MDSCs found in advanced GC suggest that they may be new therapeutic targets. Citation Format: Suguru Yamauchi, Takumi Iwasawa, Tomoaki Ito, Malcom V. Brock, Tetsu Fukunaga, Hajime Orita, Kazunori Kato. Analysis of MDSCs as a diagnostic and therapeutic target for gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5958.
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- 2023
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10. Abstract 2889: Novel subset of granulocytic MDSCs as immunosuppressive regulators and therapeutic targets in gastric cancer
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Takumi Iwasawa, Suguru Yamauchi, Tetsu Fukunaga, Hajime Orita, and Kazunori Kato
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Cancer Research ,Oncology - Abstract
The development and progression of cancers are frequently promoted by immunosuppressive cells, such as Treg and myeloid-derived suppressor cells (MDSCs) mediated by various immune checkpoint molecules. Recently, the immune checkpoint inhibitor anti-PD-1 neutralizing antibody has become available for the first-line treatment of gastric cancer (GC) in Japan. However, there is no correlation between PD-1 or PD-L1 expression in Treg or GC tissues and clinical responses to anti-PD-1 antibody. MDSCs are immature myeloid cells thought to suppress immune cell action, but the functional cell surface markers that define MDSCs correlated with cancer progression has not yet been clarified well. In this study, we identified a new subset of potential therapeutic and diagnostic targets for MDSCs in GC patients. Significantly higher levels of immune checkpoint molecules, PD-1 and PD-L1, were expressed on granulocytic MDSCs from advanced than early-stage of GC patients. Interestingly, we found that a subset of G-MDSCs expressed not only PD-1 but also PD-L1 and the pretreatment of G-MDSCs with anti-PD-1 antibody ameliorated T cell responses in vitro. We also found that G-MDSCs isolated from patients treated with anti-PD-1 antibody had a lower ability to suppress T cells. These data indicate that a novel subset of G-MDSCs expressing PD-1 found in advanced GC could be novel therapeutic targets. Citation Format: Takumi Iwasawa, Suguru Yamauchi, Tetsu Fukunaga, Hajime Orita, Kazunori Kato. Novel subset of granulocytic MDSCs as immunosuppressive regulators and therapeutic targets in gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2889.
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- 2023
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11. Serum levels of galectin-3 in idiopathic inflammatory myopathies: a potential biomarker of disease activity
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Eri Watanabe, Emiko Chiba, Takahisa Gono, Chihiro Terai, Kazunori Kato, and Shigeru Kotake
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Male ,0301 basic medicine ,Galectin 3 ,Inflammation ,Severity of Illness Index ,Polymyositis ,Proinflammatory cytokine ,03 medical and health sciences ,0302 clinical medicine ,Rheumatology ,Fibrosis ,otorhinolaryngologic diseases ,medicine ,Humans ,Pharmacology (medical) ,Lung ,Myositis ,Aged ,030203 arthritis & rheumatology ,business.industry ,Interstitial lung disease ,Middle Aged ,Dermatomyositis ,medicine.disease ,030104 developmental biology ,Galectin-3 ,Immunology ,Female ,Radiography, Thoracic ,medicine.symptom ,Lung Diseases, Interstitial ,business ,Biomarkers - Abstract
Objectives Galectin-3 is involved in various biological activities, including immune activations and fibrosis. Idiopathic inflammatory myopathies (IIMs) are autoimmune diseases of unknown aetiology, often complicated by interstitial lung disease (ILD). The aim of this study was to evaluate the expression of galectin-3 in sera and tissues of patients with IIM and assess the associations of galectin-3 with patient characteristics and disease activity. Results Serum galectin-3 levels were significantly higher in IIM patients than in healthy controls. The serum galectin-3 levels positively correlated with serum levels of inflammatory markers and proinflammatory cytokines/chemokines and the Myositis Intention-to-Treat Activity Index. Stratification analysis revealed that patients with IIM-associated ILD (IIM-ILD) had significantly higher levels of serum galectin-3 than those without IIM-ILD. In addition, patients with acute/subacute interstitial pneumonia had significantly higher levels of serum galectin-3 than those with chronic interstitial pneumonia. Furthermore, serum galectin-3 levels in IIM-ILD patients correlated with the radiological assessments of parenchymal lung involvement and treatment response. Immunohistochemical analysis revealed that galectin-3 was expressed in inflammatory cells of myositis and dermatitis sections, whereas in ILD sections, galectin-3 was expressed in interstitial fibrosis and inflammatory cells. Conclusion Galectin-3 may be involved in the pathogenesis of inflammatory and fibrotic conditions in IIM and can serve as a potential biomarker of disease activity, especially in patients with IIM-ILD.
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- 2020
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12. NK Cells Can Preferentially Target Prostate Cancer Stem-like Cells via the TRAIL/DR5 Signaling Pathway
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Kazunori Kato, Kyota Ishii, Tomohiro Yano, Yuzuki Takahama, Taiga Seki, and Yui Shimizu
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Male ,Programmed cell death ,Context (language use) ,NK cells ,urologic and male genital diseases ,Microbiology ,Biochemistry ,TNF-Related Apoptosis-Inducing Ligand ,Prostate cancer ,Cancer stem cell ,stem cells ,Cell Line, Tumor ,LNCaP ,medicine ,Humans ,Viability assay ,Cytotoxicity ,Molecular Biology ,Chemistry ,Communication ,Prostatic Neoplasms ,medicine.disease ,QR1-502 ,androgen-dependent prostate cancer ,Receptors, TNF-Related Apoptosis-Inducing Ligand ,Cancer research ,cytotoxicity ,Stem cell ,TRAIL/DR5 signal pathway - Abstract
Background: The occurrence of androgen-dependent prostate cancer mainly depends on prostate cancer stem cells. To reduce the risk of androgen-dependent prostate cancer, the direct elimination of prostate cancer stem cells is important, but an elimination strategy has not yet been established. A previous study showed that natural killer (NK) cells can preferentially target cancer stem cells in several solid tumors except prostate cancer. In this context, this study was undertaken to investigate if NK cells can selectively attack androgen-dependent prostate cancer stem cells. Methods: Prostate cancer stem-like cells were separated from an androgen-dependent prostate cancer cell line (LNCaP) using a three-dimensional culture system. LNCaP stem-like cells or LNCaP cells were co-cultured with human NK cells (KHYG-1) for 24–72 h, and cell viability was determined using the WST-8 method. The expression of each protein in the cell membrane was evaluated through FACS analysis, and mRNA levels were determined using real-time PCR. Results: KHYG-1 cells had more potent cytotoxicity against LNCaP stem-like cells than LNCaP cells, and the potency of the cytotoxicity was strongly related to the TRAIL/DR5 cell death pathway. Conclusion: NK cells can preferentially target prostate cancer stem-like cells via the TRAIL/DR5 pathway.
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- 2021
13. Altered binding avidities and improved growth inhibitory effects of novel anti-HER3 mAb against human cancers in the presence of HER1-or HER2-targeted drugs
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Yoshihisa Tomioka, Kouki Okita, Kazunori Kato, Yuichi Endo, Reiko Sugiura, Takashi Masuko, Kazue Masuko, and Kazuki Imai
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Receptor, ErbB-3 ,medicine.drug_class ,Receptor, ErbB-2 ,Biophysics ,Antibody Affinity ,Monoclonal antibody ,Lapatinib ,Biochemistry ,chemistry.chemical_compound ,Cell Line, Tumor ,Neoplasms ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Panitumumab ,Animals ,Humans ,Avidity ,skin and connective tissue diseases ,Molecular Biology ,Cell Proliferation ,Chemistry ,Antibodies, Monoclonal ,Cell Biology ,Rats ,body regions ,ErbB Receptors ,Drug Resistance, Neoplasm ,embryonic structures ,Cancer cell ,Cancer research ,Erlotinib ,Pertuzumab ,Growth inhibition ,medicine.drug ,Signal Transduction - Abstract
HER1-and HER2-targeted drugs are effective in cancer therapy, especially against lung, breast and colon malignancies; however, resistance of cancer cells to HER1-and HER2-targeted therapies is becoming a serious problem. The avidity/affinity constant (KA) and growth inhibitory effect of anti-HER3 rat monoclonal antibodies (mAb, Ab1∼Ab6) in the presence of therapeutic mAb or low-molecular-weight inhibitors against HER family proteins were analyzed by flow cytometry-based Scatchard plots (Splot) and cell proliferation assay. The KA of Ab3 and Ab6, but not Ab1 or Ab4, split into dual (high and low) modes of KA, and Ab6 exhibited greater anti-proliferative effects against LS-174T colon cancer cells in the presence of Pertuzumab (anti-HER2 mAb). A high KA by Ab6 and Ab6-mediated increased growth inhibition were observed against NCI–H1838 lung or BT474 breast cancer cells, respectively, in the presence of Panitumumab (anti-HER1 mAb) or Perutuzumab. A high KA by Ab6 and Ab6-mediated increased anti-proliferative effects against NCI–H1838 or BT474 were also respectively observed in the presence of Erlotinib (HER1 inhibitor) or Lapatinib (HER1/HER2 inhibitor). In HER1-knockout (KO) NCI–H1838, the reactivity and KA of Ab4 increased compared with in parent NCI–H1838. In HER1-KO or HER3-KO SW1116 colon cancer cells, dual modes of KA with Pertuzumab were noted, and the combination Ab6 and Pertuzumab promoted growth inhibition of HER1-KO, but not of parent SW1116.
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- 2021
14. Microplate Agglutination Test for Serological Diagnosis of Equine Paratyphoid
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Hidetaka Nagai, Hidekazu Niwa, Hirofumi Kihara, Toru Anzai, Kazunori Kato, Takehiro Kokuho, Shinji Takai, and Masato Akiba
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business.industry ,Direct agglutination test ,Medicine ,business ,Virology ,Serology - Published
- 2019
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15. Habitual cigarette smoking attenuates shear‐mediated dilation in the brachial artery but not in the carotid artery in young adults
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Kazunori Kato, Takuro Washio, Shingo Tsukamoto, Erika Iwamoto, Kazuya Suzuki, and Shigehiko Ogoh
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Central Nervous System ,Male ,medicine.medical_specialty ,Brachial Artery ,Physiology ,internal carotid artery ,Ageing and Degeneration ,030204 cardiovascular system & hematology ,Cardiovascular Physiology ,lcsh:Physiology ,Neurological Conditions, Disorders and Treatments ,03 medical and health sciences ,Cerebral circulation ,Young Adult ,0302 clinical medicine ,shear rate ,endothelial function ,nitric oxide ,Physiology (medical) ,medicine.artery ,Internal medicine ,medicine ,Tobacco Smoking ,Humans ,cardiovascular diseases ,Brachial artery ,Young adult ,Reactive hyperemia ,Original Research ,reactive oxygen species ,lcsh:QP1-981 ,business.industry ,Area under the curve ,Peripheral ,Vasodilation ,Cardiology ,cardiovascular system ,Female ,Internal carotid artery ,medicine.symptom ,business ,Hypercapnia ,Toxins, Pollutants and Chemical Agents ,030217 neurology & neurosurgery ,Blood Flow Velocity ,Carotid Artery, Internal ,circulatory and respiratory physiology - Abstract
In the present study, we hypothesized that habitual cigarette smoking attenuates endothelial function in the cerebral circulation as well as that of the peripheral circulation in young adults. To test this hypothesis, we measured cerebrovascular and peripheral flow‐mediated dilation (FMD) in young smokers and nonsmokers in the present study. Ten healthy nonsmokers and 10 smokers participated in the study. We measured blood velocity and diameter in the brachial artery and internal carotid artery (ICA) using Doppler ultrasound. We identified shear‐mediated dilation in the brachial artery and ICA by the percentage change in peak diameter during hyperemia stimulation (reactive hyperemia and hypercapnia). We measured the baseline diameter and the shear rate area under the curve from the onset of hyperemia to peak dilation in the brachial artery and ICA, finding the measurements of the smokers and those of the nonsmokers did not differ (p > .05). In contrast to brachial FMD (5.07 ± 1.79% vs. 7.92 ± 3.01%; smokers vs. nonsmokers, p = .019), FMD in the ICA was not attenuated in the smokers compared with that of the nonsmokers (5.46 ± 2.32% vs. 4.57 ± 2.70%; p = .442). These findings indicate that in young healthy smokers, cerebral endothelial function was preserved, and the response of cerebral endothelial function to smoking was different from that of peripheral vasculature., Peripheral FMD was lower in young healthy smokers than that in nonsmokers, indicating that habitual smoking attenuates peripheral endothelial function. In contrast, cerebral endothelial function was preserved in young healthy smokers. These findings suggest that the response of cerebral endothelial function to smoking is different from that of peripheral vasculature.
- Published
- 2020
16. An Agonistic Antibody to EPHA2 Exhibits Antitumor Effects on Human Melanoma Cells
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Kazunori Kato, Toshio Hasegawa, Shigaku Ikeda, and Atsushi Sakamoto
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0301 basic medicine ,Cancer Research ,Skin Neoplasms ,Cell Survival ,medicine.drug_class ,Monoclonal antibody ,Flow cytometry ,03 medical and health sciences ,Gentamicin protection assay ,Cell Movement ,Immunotoxin ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Cytotoxicity ,Melanoma ,Cell Proliferation ,Mice, Inbred BALB C ,medicine.diagnostic_test ,biology ,Chemistry ,Receptor, EphA2 ,Antibodies, Monoclonal ,General Medicine ,EPH receptor A2 ,medicine.disease ,030104 developmental biology ,Oncology ,Cancer research ,biology.protein ,RNA Interference ,Antibody - Abstract
Background/aim EPH receptor A2 (EPHA2) is highly expressed in aggressive types of human cancer, and is expected to be an excellent target molecule for antibody treatments. In this study, we investigated the therapeutic potential of antibody to EPHA2 against melanoma in vitro. Materials and methods We generated three monoclonal antibodies (mAbs) to EPHA2 and examined cell-surface expression by flow cytometry. To investigate the ability to inhibit tumor cell migration therapy with mAbs to EPHA2, we performed a wound scratch assay and invasion assay. We investigated the therapeutic effects of immunotoxins consisting of toxin-conjugated EPHA2 mAbs. Results All human melanoma cell lines studied expressed EPHA2. Like natural ligand ephrin-A1, one of EPHA2 mAbs, SHM16, inhibited metastatic behavior of cells, such as migration and invasion. In addition, drastic growth inhibition and cytotoxicity were found using immunotoxin-conjugated SHM16. Conclusion These observations indicate a promising role for EPHA2 as a target in antibody treatments for melanoma, and demonstrate the potential therapeutic effects of an agonistic antibody to EPHA2.
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- 2018
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17. Effect of cigarette smoking on hypercapnia induced shear‐mediated dilation in the internal carotid artery
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Shigehiko Ogoh, Shingo Tsukamoto, Takuro Washio, Erika Iwamoto, Kazuya Suzuki, and Kazunori Kato
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medicine.medical_specialty ,business.industry ,Biochemistry ,Dilation (metric space) ,Shear (geology) ,Cigarette smoking ,Internal medicine ,medicine.artery ,Genetics ,medicine ,Cardiology ,medicine.symptom ,Internal carotid artery ,business ,Molecular Biology ,Hypercapnia ,Biotechnology - Published
- 2019
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18. Aminopeptidase N (APN/CD13) as a target molecule for scirrhous gastric cancer
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Shigeo Nohara, Kazuyoshi Yanagihara, Yoshiaki Kajiyama, Daisuke Fujiwara, Yoshimi Iwanuma, Naoya Sakuragi, and Kazunori Kato
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,Cell ,Antineoplastic Agents ,CD13 Antigens ,Article ,Targeted therapy ,03 medical and health sciences ,0302 clinical medicine ,Leucine ,Stomach Neoplasms ,Cancer stem cell ,Cell Line, Tumor ,medicine ,Humans ,Cytotoxic T cell ,Hepatology ,Cluster of differentiation ,biology ,business.industry ,Immunotoxins ,CD44 ,Gastroenterology ,Cancer ,Aldehyde Dehydrogenase ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Cancer cell ,Cancer research ,biology.protein ,Cisplatin ,business - Abstract
Summary Background Scirrhous gastric cancer is associated with peritoneal dissemination and advanced lymph node metastasis from an early stage, and the prognosis is still poor. In this study, we aimed to analyze candidate molecules for targeted therapy of scirrhous gastric cancer. We searched for molecules/metabolic activity that might be predominantly expressed in a subpopulation of scirrhous gastric cancer cells and might function as cancer stem cell markers. Results For this purpose, we investigated the expression of various cell surface markers and of aldehyde dehydrogenase (ALDH) activity. These analyses showed that the scirrhous gastric cancer cell lines HSC-58 and HSC-44PE heterogeneously expressed CD13, while CD44, CDCP1, EpCAM and ABCG2 were expressed uniformly. Moreover, 10% of the total HSC-58 cell population expressed ALDH enzyme activity. A subpopulation of cells strongly positive for ALDH also expressed high levels of CD13, both of which are known as cancer stem cell markers. HSC-58 cells expressing high levels of CD13 showed lower sensitivity to a cancer drug cisplatin than cells with low levels of CD13. In contrast, CD13 -high subpopulation of HSC-58 was more sensitive to an aminopeptidase N inhibitor bestatin. In terms of antibody-drug therapy, anti-CD13-immunotoxin was highly cytotoxic towards HSC-58 cells and was more cytotoxic than anti-EpCAM-immunotoxin. Conclusion These data suggest that CD13 is a suitable cell surface candidate for targeted antibody-drug therapy of scirrhous gastric cancer.
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- 2016
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19. Abstract 1020: Anti-oxidant amino acid L-ergothioneine exhibits immunomodulatory effect by regulating immunosuppressive cytokine production of tumor cells
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Yui Shimizu, Kazunori Kato, and Katsuhiro Kuroki
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Cancer Research ,Angiogenesis ,medicine.medical_treatment ,Spleen ,CCL2 ,In vitro ,chemistry.chemical_compound ,Cytokine ,medicine.anatomical_structure ,Oncology ,chemistry ,Ergothioneine ,Cell culture ,Cancer research ,medicine ,Erg - Abstract
Ergothioneine (ERG) is a natural antioxidant nutrient containing in edible golden oyster mushroom, Pleurotus cornucopiae (Tamogitake). In previous AACR meeting, we reported that administration of ERG rich water extracts of p. cornucopiae to tumor-bearing mice could suppress the growth of subcutaneous tumors and reduce the number of regulatory T cells (Treg) in lymph node and spleen. However, the molecular events inducing antitumor and immunomodulatory effects are still unknown. Our aim is to identify the mechanism of ERG in tumor cells which secrete various immunomodulatory cytokines. We cocultured human tumor cell lines with ERG and tested cytokine concentration in culture supernatants and expression of immune checkpoint molecules on tumors. ERG could significantly inhibit the production of VEGF, CCL2 and TGF-β1 which are important in not only angiogenesis and tumor invasion but also Treg induction. Importantly, ERG also reduced the expression of some immune checkpoint molecules on tumor cells and prolonged the survival of IL-2-activated lymphocytes in vitro. Overall, ERG rich water extract of p. citrinopileatus might inhibit the induction of Treg in tumor-bearing host via suppression of VEGF and TGF-β1, indicating a novel immunomodulatory antioxidant nutrient in mushrooms Citation Format: Kazunori Kato, Katsuhiro Kuroki, Yui Shimizu. Anti-oxidant amino acid L-ergothioneine exhibits immunomodulatory effect by regulating immunosuppressive cytokine production of tumor cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1020.
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- 2020
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20. Advanced microscopic evaluation of parallel type I and type II cell deaths induced by multi-functionalized gold nanocages in breast cancer
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Anindito Sen, D. Sakthi Kumar, Sreejith Raveendran, Hiromi Ito-Tanaka, Kazunori Kato, and Toru Maekawa
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Cell ,Cellular homeostasis ,Bioengineering ,02 engineering and technology ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,Breast cancer ,Nanocages ,Lysosome ,Medicine ,General Materials Science ,business.industry ,Autophagy ,General Engineering ,General Chemistry ,021001 nanoscience & nanotechnology ,medicine.disease ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,medicine.anatomical_structure ,Cancer cell ,Cancer research ,0210 nano-technology ,business ,Carcinogenesis - Abstract
Despite aggressive surgical resections and combinatorial chemoradiations, certain highly malignant populations of tumor cells resurrect and metastasize. Mixed-grade cancer cells fail to respond to standard-of-care therapies by developing intrinsic chemoresistance and subsequently result in tumor relapse. Macroautophagy is a membrane trafficking process that underlies drug resistance and tumorigenesis in most breast cancers. Manipulating cellular homeostasis by a combinatorial nanotherapeutic model, one can evaluate the crosstalk between type I and type II cell death and decipher the fate of cancer therapy. Here, we present a multi-strategic approach in cancer targeting to mitigate the autophagic flux with subcellular toxicity via lysosome permeation, accompanied by mitochondrial perturbation and apoptosis. In this way, a nanoformulation is developed with a unique blend of a lysosomotropic agent, an immunomodulating sulfated-polysaccharide, an adjuvant chemotherapeutic agent, and a monoclonal antibody as a broad-spectrum complex for combinatorial nanotherapy of all breast cancers. To the best of our knowledge, this manuscript illustrates for the first time the applications of advanced microscopic techniques such as electron tomography, three-dimensional rendering and segmentation of subcellular interactions, and fate of the multifunctional therapeutic gold nanocages specifically targeted toward breast cancer cells.
- Published
- 2018
21. Therapeutic Monoclonal Antibodies for Cancer: The Past, Present, and Future
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Kazunori Kato
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business.industry ,CTLA-4 ,medicine.drug_class ,Immunology ,Medicine ,Cancer ,business ,medicine.disease ,Monoclonal antibody ,Immune checkpoint - Published
- 2015
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22. An ‘all in one’ approach for simultaneous chemotherapeutic, photothermal and magnetic hyperthermia mediated by hybrid magnetic nanoparticles
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Sivakumar Balasubramanian, Venugopal Kizhikkilot, Seiki Iwai, Yutaka Nagaoka, Toru Maekawa, Aswathy Ravindran Girija, Kazunori Kato, Sakthikumar Dasappan Nair, Takahiro Fukuda, Balasubramanian, Sivakumar, Ravindran, Girija Aswathy, Nagaoka, Yutaka, Fukuda, Takahiro, Iwai, Seiki, Kizhikkilot, Venugopal, Kato, Kazunori, Maekawa, Toru, and Nair, Sakthikumar Dasappan
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magnetic nano-particles ,General Chemical Engineering ,Cancer ,Nanotechnology ,General Chemistry ,Photothermal therapy ,medicine.disease ,cancer therapeutics ,PLGA ,chemistry.chemical_compound ,Magnetic hyperthermia ,chemistry ,nanoscience and nanotechnologies ,magnetism ,Cancer cell ,Drug delivery ,cytology ,medicine ,cells ,Magnetic nanoparticles ,Nanoconjugates - Abstract
Nanoscience and nanotechnology utilize nanoparticles to provide several remarkable applications in biomedical fields such as bio imaging, diagnosis of several diseases, and efficient drug delivery. Multifunctional magnetic nanoparticles (MNPs) are a significant type of nanomaterials that are capable of developing therapeutic as well as diagnostic (theragnostic) applications. Multifunctional hybrid magnetic nanoparticles, as efficient theragnostic representatives, have been developed. The hybrid magnetic nanoparticles (HMNP)-Au-MNPs have been assimilated into PLGA NPs along with two potent chemotherapeutic agents (curcumin and gemcitabine). Delivering chemotherapeutics into cancer cells with multiple targeting moieties is an attractive area in cancer therapeutics. In this study, the nanoconjugates have been tailored to target the pancreatic and breast cancer cells by attaching three specific targeting ligands (folate, transferrin and AS1411 aptamer). Moreover, we report a nanoparticle-based delivery system that can deliver therapeutic cargos to the cancer cells and can exert its lethality by three distinctive modes (chemotherapeutic, photothermal and magnetic hyperthermia) either independently or by the synergistic action of drug and hyperthermia. Overall our results display an 'all in one' approach with the same nanoformulation for the combined destruction of cancer cells. The developed nanoformulation was highly versatile in terms of the choice of implementing lethality, depending on the cancer type. Refereed/Peer-reviewed
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- 2015
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23. A Novel Screening Method to Establish Tumor-targeting Antibodies Reliable for Drug Delivery System
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Kazunori Kato
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Pharmacology ,biology ,Chemistry ,medicine.drug_class ,medicine.medical_treatment ,Antibodies, Monoclonal ,Pharmaceutical Science ,Epithelial cell adhesion molecule ,Monoclonal antibody ,Adenoviridae ,Targeted therapy ,chemistry.chemical_compound ,Drug Delivery Systems ,Carcinoembryonic antigen ,Antigen ,Drug Design ,Cancer cell ,medicine ,biology.protein ,Cancer research ,Humans ,Molecular Targeted Therapy ,Epidermal growth factor receptor ,Drug Screening Assays, Antitumor ,Antibody - Abstract
Establishment of a system that allows selective drug delivery and gene silencing to a tumor is expected to enable targeted therapy. We constructed a genetically modified adenovirus incorporating an IgG Fc-binding motif from the Staphylococcus protein A, Z33 (Adv-FZ33). By cross-linking the Adv-FZ33 virus and the surface antigen molecules with the targeting monoclonal antibodies (mAbs), we attained highly enhanced gene deliveries into the respective antigen-positive cancer cells. Therefore, we aimed to establish a systematic screening method to search for antibody and cell surface target candidates that would provide highly selective anti-cancer reagents to malignant tumors. Using an Adv-FZ33, hybridoma libraries producing a variety of mAbs for human pancreatic, prostate, lung or ovarian carcinoma cells were screened, and we were able to selectively obtain several mAbs which had potent high affinity and recognized antigens of high structure. Within these mAbs, we have identified tumor cell target molecules including not only carcinoembryonic antigen (CEA), epithelial cell adhesion molecule (EpCAM), epidermal growth factor receptor (EGFR), prostate specific membrane antigen (PSMA) but also novel tumor surface target molecules such as phosphatidic acid phosphatase type 2a (PAP2a) and interleukin-13 receptor variant α2 (IL-13Rα2) as tumor antigens. Overall, these results indicate that this type of inductive method approach is a reliable strategy for screening in antibody therapy on par with antibody-dependent drug-delivery system.
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- 2013
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24. Cell Surface Antibody Retention Influences In Vivo Antitumor Activity Mediated by Antibody-dependent Cellular Cytotoxicity
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Kazuyasu Nakamura, Kazunori Kato, Miki Yamaguchi, Hirofumi Hamada, Masahiro Ikeda, and Yoshiyuki Sugimoto
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Antibody-dependent cell-mediated cytotoxicity ,Cancer Research ,biology ,medicine.drug_class ,Chemistry ,Cell ,Antibody-Dependent Cell Cytotoxicity ,Antibodies, Monoclonal ,General Medicine ,TACSTD2 ,Monoclonal antibody ,Xenograft Model Antitumor Assays ,In vitro ,medicine.anatomical_structure ,Oncology ,In vivo ,Antigens, Neoplasm ,Cell Line, Tumor ,medicine ,biology.protein ,Cancer research ,Humans ,Antibody ,Cytotoxicity ,Cell Adhesion Molecules - Abstract
Background Multiple factors affect the in vivo antitumor activity of antibody-based therapeutics; however, the influence of cell surface retention on antibody-dependent cellular cytotoxicity (ADCC) is not fully understood. Here we evaluated the importance of cell surface antibody retention in antitumor activity mediated by ADCC in vivo. Materials and methods Two mAbs against tumor-associated calcium signal transducer 2 (TACSTD2/TROP2), AR47A6.4.2 and Pr1E11, were used. Antitumor activities against BxPC3 and Colo205 cells were investigated through in vitro and in vivo assays. Results Pr1E11 showed better cell surface retention than AR47A6.4.2 in vitro although Pr1E11 and AR47A6.4.2 showed equivalent ADCC activity. Complement-dependent cytotoxicity and antiproliferative activity were not observed for either antibody. Pr1E11 exhibited higher antitumor activity than AR47A6.4.2 in vivo. Conclusion Our results suggest that high cell surface retention can result in potent ADCC activity in vivo. This observation could provide novel insight into how effectively screen for antibodies with strong in vivo antitumor activity.
- Published
- 2016
25. Diagnostic Technique for Deterioration Inspection of Metallic Products through the In situ Measurement Using a Thermophysical Handy Tester
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Ichiro Takahashi and Kazunori Kato
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In situ ,Materials science ,business.industry ,Atomic and Molecular Physics, and Optics ,Metal ,Thermal conductivity ,Nondestructive testing ,visual_art ,visual_art.visual_art_medium ,General Materials Science ,Composite material ,business ,Engineering (miscellaneous) ,Instrumentation - Published
- 2010
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26. [Untitled]
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Kazunori KATO
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General Engineering - Published
- 2009
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27. Gene transfer of CD40-ligand to dendritic cells stimulates interferon-γ production to induce growth arrest and apoptosis of tumor cells
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Kiminori Nakamura, Yukari Masuta, Hirohumi Hamada, Jianhua Huang, H Uchida, Toshihiro Tanaka, Kei Tomihara, Hiroyoshi Hiratsuka, Kazunori Kato, and Katsunori Sasaki
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Skin Neoplasms ,CD40 Ligand ,Transplantation, Heterologous ,Gene Expression ,Mice, Nude ,Apoptosis ,chemical and pharmacologic phenomena ,TNF-Related Apoptosis-Inducing Ligand ,Interferon-gamma ,Mice ,Transduction, Genetic ,immune system diseases ,Interferon ,Cell Line, Tumor ,parasitic diseases ,Genetics ,medicine ,Animals ,Humans ,Interferon gamma ,CD154 ,Molecular Biology ,CD40 ,biology ,Cell growth ,hemic and immune systems ,Dendritic Cells ,Genetic Therapy ,Dendritic cell ,Interleukin-12 ,Receptors, TNF-Related Apoptosis-Inducing Ligand ,surgical procedures, operative ,Cell culture ,Models, Animal ,Immunology ,Carcinoma, Squamous Cell ,biology.protein ,Cancer research ,Molecular Medicine ,Immunotherapy ,A431 cells ,medicine.drug - Abstract
In this study, we present evidence that gene transfer of the CD40-ligand (CD154) into human immature dendritic cells (DC) imparts direct antitumor effects on tumor cells. DC infected with adenovirus directed to express human CD154 on the cell surface (CD154-DC) elicited significantly higher levels of immune accessory molecules commonly found on mature DC. We found that co-cultivation with a human squamous cell carcinoma cell line (OSC-70) with CD154-DC significantly inhibited cell growth. We further demonstrate that OSC-70 cells stimulated with CD154-DC were more susceptible to apoptosis via TNF-related apoptosis inducing ligand (TRAIL). Importantly, tumor cells co-cultured with CD154-DC in transwell plates expressed upregulated cell surface TRAIL-R2. CD154-DC produced higher levels of interferon (IFN)-gamma, IL-12p70 and soluble CD154, but the ability of CD154-DC to inhibit tumor cell growth was significantly abrogated by a neutralizing antibody to IFN-gamma, indicating that this was mainly mediated by IFN-gamma. Furthermore, intratumoral injection of CD154-DC significantly suppressed OSC-70 tumor growth in a xenograft model. Overall, these results reveal that CD154-DC have potential as an anti-cancer therapy by producing IFN-gamma to arrest adjacent tumor cell growth and increase the susceptibility of apoptosis via TRAIL.
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- 2007
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28. Metalloprotease inhibitors block release of soluble CD27 and enhance the immune stimulatory activity of chronic lymphocytic leukemia cells
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Satoshi Takahashi, Kazunori Kato, Thomas J. Kipps, Hirofumi Hamada, and Peter Chu
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Cancer Research ,Proteases ,Phenylalanine ,T-Lymphocytes ,medicine.medical_treatment ,Lymphocyte ,Chronic lymphocytic leukemia ,Thiophenes ,Biology ,Hydroxamic Acids ,Immune system ,Antigen ,immune system diseases ,hemic and lymphatic diseases ,Genetics ,medicine ,Humans ,Protease Inhibitors ,Molecular Biology ,Protease ,Dose-Response Relationship, Drug ,Cell Biology ,Hematology ,medicine.disease ,Leukemia, Lymphocytic, Chronic, B-Cell ,Molecular biology ,Tumor Necrosis Factor Receptor Superfamily, Member 7 ,Leukemia ,Phenotype ,medicine.anatomical_structure ,Solubility ,Metalloproteases ,CD80 ,CD27 Ligand - Abstract
Objective Chronic lymphocytic leukemia (CLL) B cells from most patients express both membrane-bound CD27 (mCD27) and soluble CD27 (sCD27). Expression of sCD27 inhibits CD27-dependent T-cell or CLL-cell activation mediated by its ligand, CD70. In this study, we evaluated whether protease inhibitors could inhibit the release of sCD27 from CLL cells and enhance T-cell activation mediated by CD27-CD70 interaction. Methods CLL cells exposed to hydroxamic acid-based matrix metalloprotease (MMP) inhibitors were evaluated for the release of sCD27 by sandwich enzyme-linked immunosorbent assay and immunoprecipitation. We examined for phenotypic changes in CLL cells treated with MMP inhibitors by flow cytometry and T-cell activation by CLL cells was assessed by [ 3 H] thymidine incorporation assay and the production of interferon-gamma. Results Treatment of CLL cells with MMP inhibitors blocked the release of sCD27 to the culture supernatant. In contrast, a non–hydroxamic acid control compound or inhibitors of other proteases, including serine, cysteine, and aspartyl proteases, were ineffective. Furthermore, CLL cells treated with MMP inhibitors expressed significantly higher levels of accessory molecules, such as CD54, CD80, and CD95. Consistent with such changes, we found that CLL cells treated with MMP inhibitors, but not control treated cells, could stimulate allogeneic and autologous T cells in mixed lymphocyte reactions. Conclusion These data reveal that metalloprotease inhibitors can block production of sCD27, which can interfere with mCD27-CD70 interactions that induce expression of immune costimulatory molecules on CLL B cells. Conceivably, treatment of CLL cells with metalloprotease inhibitors may enhance their potential for stimulating cellular immune recognition of leukemia-associated antigens.
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- 2007
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29. Diagnostic Technique for Degradation of Engineering Materials by Measurement of Thermophysical Properties
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Ichiro Takahashi and Kazunori Kato
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Fluid Flow and Transfer Processes ,Materials science ,Thermal conductivity ,Material Degradation ,Metallic materials ,Thermal ,Degradation (geology) ,Surface layer ,Composite material ,Condensed Matter Physics ,Temperature response ,Degree (temperature) - Abstract
The thermal conductivity of the surface layer of engineering materials changes in the early stages of material degradation due to the appearance of micro-cracks. A new method for evaluating and assessing the degree of degradation of a material using this change is proposed herein. The influence of the micro-cracked layer on the temperature response as measured by a thermophysical handy tester was theoretically examined. By defining a thermal degradation parameter, the amount of degradation of various materials was evaluated. In order to verify this theory, fatigue tests using metallic materials were conducted. Comparisons before and after the fatigue tests were then made to establish the correlation between the density of micro-cracks and the decrease in thermal conductivity. As a result, it was ascertained that a thermal degradation parameter can easily be estimated from a temperature response curve obtained using the tester. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(8): 501–512, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20178
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- 2007
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30. Selective gene delivery into target cells by fiber-modified adenovirus
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Hirofumi Hamada and Kazunori Kato
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Chemistry ,Pharmaceutical Science ,Fiber ,Gene delivery ,Cell biology - Abstract
筆者らは,プロテインA由来の33個ペプチド配列をファイバー部に組み込んだアデノウイルス(Adv-FZ33)を作製しその生物活性を検討してきた.さまざまなヒト腫瘍標的細胞と結合し,このファイバー変異型アデノウイルスを介した遺伝子導入効率を増強できる標的化抗体の網羅的な樹立法の開発に成功した.
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- 2007
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31. Strategist PLGA Nano-capsules to Deliver siRNA for Inhibition of Carcinoma and Neuroblastoma Cell Lines by Knockdown of MYC Proto-oncogene using CPPs and PNA
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Toru Maekawa, Yutaka Nagaoka, Kotaro Matsumoto, Archana Raichur, Kazunori Kato, Yoshikata Nakajima, Toru Mizuki, and D. Sakthi Kumar
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Cancer Research ,Gene knockdown ,Small interfering RNA ,Polymers and Plastics ,Oncogene ,Cell growth ,Health, Toxicology and Mutagenesis ,Biomedical Engineering ,Biophysics ,Biology ,Biomaterials ,RNA interference ,Gene expression ,Cancer cell ,Cell-penetrating peptide ,Cancer research ,Molecular Biology - Abstract
RNA interference and the therapeutic applications using small interfering RNA was discovered more than 10 years ago and currently is used in various applications including in therapeutic field. However the research in this field is still in its infancy. Many challenges like safe delivery of targeted siRNA to nucleus and cytosol of cancerous cells without compromising the activity of siRNA needs to be addressed. We have overcome this hurdle with the help of nanotechnology using PLGA hollow nanoparticles (PLGAHNPs) and suppressing the oncogene of MYC transcription factors by using anti myc-siRNAs in human cancer cell lines. siRNA was encapsulated in PLGAHNPs. These spherical PLGAHNPs of size 70 nm had high efficiency of gene release at pH 4.2 under in vitro conditions. Cell penetrating peptide (CPP)- Tat peptide (TAT) and peptide nucleic acidnucleolus localizing signal (PNA-NLS) was used for siRNA delivery without affecting the therapeutic activity of siRNA. The siRNA duplex was prepared using T7 polymerase and double stranded DNA through in vitro transcription. Incubation of the siRNA encapsulated PLGAHNPs functionalized with TAT and PNA-NLS (TAT-siRNA-PNA-PLGAHNPs-siRNA) with cancer cells resulted in reduced cell proliferation. A downregulation of gene expression by 90% was observed even with low concentration of siRNA. We found complete arrest of cell division which was mediated by downregulation of MYC expression.
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- 2015
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32. Carcinoembryonic Antigen–Targeted Selective Gene Therapy for Gastric Cancer through FZ33 Fiber-Modified Adenovirus Vectors
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Naoki Watanabe, Hirofumi Hamada, Masahide Kuroki, Jianhua Huang, Sachie Hirai, Kei Tomihara, Toshihiro Tanaka, Motomu Kuroki, and Kazunori Kato
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Cancer Research ,Genetic enhancement ,Genetic Vectors ,Molecular Sequence Data ,Mutant ,CHO Cells ,Biology ,Gene delivery ,Adenoviridae ,Nude mouse ,Carcinoembryonic antigen ,Antigen ,Stomach Neoplasms ,Cell Line, Tumor ,Cricetinae ,medicine ,Animals ,Humans ,Amino Acid Sequence ,Promoter Regions, Genetic ,DNA Primers ,Base Sequence ,Cancer ,Genetic Therapy ,biology.organism_classification ,medicine.disease ,Carcinoembryonic Antigen ,Globins ,Oncology ,Cancer cell ,Immunology ,biology.protein ,Cancer research - Abstract
Purpose: A major problem when using the adenoviral vectors for gene therapy applications is thought to be related to low transduction efficiency in cancer cells or to side effects in normal cells. There is an urgent requirement to improve the specificity of gene delivery in the context of cancer gene therapy.Experimental Design: We constructed a genetically modified adenovirus incorporating an IgG Fc-binding motif from the Staphylococcus protein A, Z33, within the HI loop (Adv-FZ33). A remarkable degree of targeted gene delivery to gastric cancer cells was obtained with Adv-FZ33 with the fully human anti–carcinoembryonic antigen (CEA) monoclonal antibody, C2-45.Results: In vitro LacZ or EGFP gene expression after Adv-FZ33 infection via C2-45 was 20 times higher than control monoclonal antibody in MKN-45 at 1,000 viral particles/cell. We generated Ax3CAUP-FZ33 (UP-FZ33), which is an Adv-FZ33 derivative vector expressing a therapeutic gene (i.e., Escherichia coli uracil phosphoribosyltransferase), which converts 5-fluorouracil (5-FU) directly to 5-fluoro-UMP. UP-FZ33 with C2-45 enhanced the cytotoxicity of 5-FU by 10.5-fold in terms of IC50 against MKN-45 compared with control IgG4. In a nude mouse peritoneal dissemination model, tumor growth in mice treated with UP-FZ33/C2-45/5-FU was significantly suppressed, and tumor volumes were less than one-fourth of those of the control IgG4 group (P < 0.05). The median survival time of the UP-FZ33/C2-45/5-FU group was significantly longer than those treated with PBS or 5-FU only (P < 0.01).Conclusions: These data suggest that CEA-targeted FZ33 mutant adenovirus-mediated gene delivery offers a strong and selective therapeutic modality against CEA-producing cancers.
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- 2006
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33. Wall Slip in a Narrow-Gap Channel for an Encapsulating Epoxy Molding Compound for Semiconductor Devices
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Ryoji Kawasaki, Kazunori Kato, and Masaki Yoshii
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Materials science ,Wall slip ,visual_art ,Narrow gap ,visual_art.visual_art_medium ,Semiconductor device ,Epoxy ,Composite material - Published
- 2006
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34. Quality inspection in polymer processing by a thermophysical handy tester
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Ichiro Takahashi, Ichiro Kano, Kazunori Kato, and Yasuyuki Koshikawa
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Fluid Flow and Transfer Processes ,chemistry.chemical_classification ,Crystallinity ,Measurement method ,Filler (packaging) ,Thermal conductivity ,Quality (physics) ,Materials science ,chemistry ,Unsaturated polyester ,Polymer ,Composite material ,Condensed Matter Physics - Abstract
This paper presents the applicability of a thermophysical handy tester for quality inspection and diagnostic technique such as in situ measurement of polymeric resin products. Influence of crystallinity known as a rating factor of quality, or filler concentration upon thermal conductivity is determined for the case of unsaturated polyester resin products by using the tester. Consequently, good correlations between the thermal conductivity and the crystallinity or the filler concentration are certified. The variation or the distribution of thermal conductivity of products molded under various conditions can be detected nondestructively using the tester. As an example, the thermal conductivity distribution around the forming gate is demonstrated, indicating the density-uniformity of the resin product. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(6): 421–433, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20124
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- 2006
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35. Delivery of Condensed DNA by Liposomal Non-viral Gene Delivery System into Nucleus of Dendritic Cells
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Masaharu Ueno, Kazunori Kato, Kentaro Kogure, Arisa Minoura, Shiroh Futaki, Hidetaka Akita, Tomoya Masuda, Takashi Nakamura, Rumiko Moriguchi, Hideyoshi Harashima, and Hirofumi Hamada
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Nuclear Localization Signals ,Pharmaceutical Science ,Biology ,Gene delivery ,Mice ,chemistry.chemical_compound ,Plasmid ,Gene expression ,medicine ,Animals ,Humans ,Luciferase ,Luciferases ,Cell Nucleus ,Pharmacology ,Gene Transfer Techniques ,DNA ,Dendritic Cells ,General Medicine ,Cell biology ,Cell nucleus ,medicine.anatomical_structure ,chemistry ,Liposomes ,NIH 3T3 Cells ,Nucleus ,Nuclear localization sequence ,HeLa Cells ,Plasmids - Abstract
In this study, we developed novel double-membranous non-viral gene delivery system modified with SV-40 T antigen-derived nuclear localization signal (NLS-DMEND) for delivery of luciferase plasmid DNA to nucleus of non-dividing mouse bone marrow-derived dendritic cells (BMDC). Intracellular trafficking and gene expression of NLS-DMEND in the BMDC were evaluated. Condensed DNA was observed in the nucleus by confocal laser scanning microscopy, and the NLS-DMEND induced significant luciferase activity in the BMDC. It was suggested that the condensed DNA particle transferred into nucleus via energy dependent manner, since the nuclear transfer was inhibited by metabolic inhibitors. In conclusion, condensed plasmid DNA was delivered into the nucleus of non-dividing BMDC by NLS-DMEND.
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- 2006
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36. Advanced microscopic evaluation of parallel type I and type II cell deaths induced by multi-functionalized gold nanocages in breast cancer.
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Sreejith Raveendran, Sen, Anindito, Hiromi Ito-Tanaka, Kazunori Kato, Toru Maekawa, and Kumar, D. Sakthi
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- 2019
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37. Bcl-xL Gene Transfer Inhibits Bax Translocation and Prolongs Cardiac Cold Preservation Time in Rats
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Yukari Masuta, Kei Tomihara, Kazunori Kato, Toshihiro Tanaka, Takeshi Uzuka, Masayuki Morikawa, Kiminori Nakamura, Yoshinori Ito, Keiji Ishii, Hirofumi Hamada, Sachie Hirai, and Jianhua Huang
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Male ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,bcl-X Protein ,Ischemia ,Apoptosis ,Myocardial Reperfusion ,Myocardial Reperfusion Injury ,Bcl-xL ,Gene transfer ,Mitochondria, Heart ,Cytosol ,Transduction, Genetic ,Physiology (medical) ,medicine ,Animals ,Cold preservation ,bcl-2-Associated X Protein ,Cryopreservation ,Heart transplantation ,biology ,Bax translocation ,business.industry ,Myocardium ,Graft Survival ,Heart ,Organ Preservation ,medicine.disease ,Rats ,Protein Transport ,Rats, Inbred Lew ,biology.protein ,Cancer research ,Heart Transplantation ,Cardiology and Cardiovascular Medicine ,business ,Reperfusion injury - Abstract
Background— Apoptosis is an important cause of early graft loss after heart transplantation. Bcl-xL was reported to protect the heart against normothermic ischemia and reperfusion injury. In this study, we determined whether overexpression of Bcl-xL could inhibit tissue injury resulting from prolonged cold preservation followed by warm reperfusion of heart transplants. Methods and Results— Lewis rat hearts were transduced with an adenovirus vector harboring Bcl-xL cDNA (AxCAhBclxL) 4 days before collection of tissue. After preservation in University of Wisconsin solution at 4°C for 24 hours, the heart was either perfused with a Langendorff device ex vivo or used for heterotopic heart transplantation in vivo. Bcl-xL gene transfer significantly reduced the infarct size (23.0±2.6% versus 47.7±7.0% in saline control and 48.6±6.1% in vector control, P P c release from the mitochondria; it also significantly decreased cardiac cell apoptosis and improved graft survival rate after long cold preservation, followed by warm reperfusion. Conclusions— Bcl-xL gene transfer inhibited the translocation of Bax and prolonged the cold preservation time of cardiac transplants. This may be a potential therapeutic method in clinical practice.
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- 2005
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38. A Study on Crack Prevention at Service State of Reinforced Concrete Member Fortified Tension Zone by Reactive Powder Composite
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Isao Ujike, Masato Numata, Yoshimitsu Konishi, and Kazunori Kato
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Materials science ,Serviceability (structure) ,business.industry ,Mechanical Engineering ,Structural engineering ,Condensed Matter Physics ,Durability ,Flexural strength ,Mechanics of Materials ,Reinforced solid ,Ultimate tensile strength ,Bending moment ,General Materials Science ,Limit state design ,Composite material ,business ,Beam (structure) - Abstract
Cracks in concrete structure cause deterioration of durability due to corrosion of reinforcement. Although crack width is controlled in less than the allowable value in the present design method, concrete structure with cracks deteriorate more easily than that without cracks. The objective of this study is to develop the reinforced concrete member that a crack doesn't occur in serviceability limit state. This study gave attention to a super high strength of Reactive Powder Composite (RPC), especially a high tensile strength on crack development. RPC consists of premixed powder in selected combination of cement, silica particles, siliceous sand, special water reducing agent, and steel fibers.A part of tension zone in reinforced concrete beam was fortified by RPC. The cross-sectional area of RPC part was varied in three ways. Flexural load tests of beam were carried out. The crack development moment of the beams fortified by RPC increased with the increase of reinforcing area of RPC. When the bending moment that the cracks with permissible crack width for corrosion of reinforcement develop in the usual reinforced concrete beam acted, cracks didn't occur in the beams reinforced with RPC suitably. The flexural behaviours of the beam reinforced with RPC could be analysed by elastic theory in the range of service state. When the bending moment on the occurrence of the crack is estimated, the restraint stress due to autogeneous shrinkage of RPC must be taken into consideration.
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- 2005
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39. Mesenchymal stem cells that produce neurotrophic factors reduce ischemic damage in the rat middle cerebral artery occlusion model
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Kazunori Kato, Osamu Honmou, Hirofumi Hamada, Sachie Hirai, Masayoshi Kobune, Katsunori Sasaki, Isao Date, Yoshinori Ito, Kazuhiko Kurozumi, Kiminori Nakamura, Yutaka Kawano, Takashi Tamiya, Hiroaki Uchida, Keiji Ishii, and Kiyohiro Houkin
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Tetrazolium Salts ,Ciliary neurotrophic factor ,Brain Ischemia ,Cell therapy ,Neurotrophic factors ,Internal medicine ,Drug Discovery ,Genetics ,Glial cell line-derived neurotrophic factor ,Animals ,Humans ,Medicine ,Nerve Growth Factors ,Rats, Wistar ,Hematoxylin ,Molecular Biology ,Stroke ,Cells, Cultured ,Pharmacology ,Staining and Labeling ,biology ,business.industry ,Cerebral infarction ,Mesenchymal stem cell ,Infarction, Middle Cerebral Artery ,Mesenchymal Stem Cells ,Genetic Therapy ,medicine.disease ,Rats ,Disease Models, Animal ,Endocrinology ,Cytokine ,nervous system ,biology.protein ,Eosine Yellowish-(YS) ,Molecular Medicine ,business - Abstract
Mesenchymal stem cells (MSC) were reported to ameliorate functional deficits after stroke in rats, with some of this improvement possibly resulting from the action of cytokines secreted by these cells. To enhance such cytokine effects, we previously transfected the telomerized human MSC with the BDNF gene using a fiber-mutant adenovirus vector and reported that such treatment contributed to improved ischemic recovery in a rat transient middle cerebral artery occlusion (MCAO) model. In the present study, we investigated whether other cytokines in addition to BDNF, i.e., GDNF, CNTF, or NT3, might have a similar or greater effect in this model. Rats that received MSC-BDNF (P < 0.05) or MSC-GDNF (P < 0.05) showed significantly more functional recovery as demonstrated by improved behavioral test results and reduced ischemic damage on MRI than did control rats 7 and 14 days following MCAO. On the other hand, rats that received MSC-CNTF or MSC-NT3 showed neither functional recovery nor ischemic damage reduction compared to control rats. Thus, MSC transfected with the BDNF or GDNF gene resulted in improved function and reduced ischemic damage in a rat model of MCAO. These data suggest that gene-modified cell therapy may be a useful approach for the treatment of stroke.
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- 2005
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40. Adenovirus-Mediated Transfer of siRNA against Survivin Induced Apoptosis and Attenuated Tumor Cell Growth in Vitro and in Vivo
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Yoshinori Ito, Kazunori Kato, Masayoshi Kobune, Katsunori Sasaki, Kazunari Taira, Hiroaki Uchida, Hideaki Tahara, Hirofumi Hamada, Toshihiro Tanaka, Makoto Miyagishi, and Hironari Dehari
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Small interfering RNA ,Survivin ,Genetic enhancement ,Genetic Vectors ,Apoptosis ,Mice, Inbred Strains ,Biology ,Adenoviridae ,Inhibitor of Apoptosis Proteins ,Viral vector ,Mice ,Cell Line, Tumor ,Neoplasms ,Drug Discovery ,Sense (molecular biology) ,Genetics ,Animals ,Humans ,RNA, Small Interfering ,Molecular Biology ,Cell Proliferation ,Pharmacology ,Gene knockdown ,Gene targeting ,Genetic Therapy ,Xenograft Model Antitumor Assays ,Molecular biology ,Neoplasm Proteins ,Gene Targeting ,Cancer cell ,Cancer research ,Molecular Medicine ,Microtubule-Associated Proteins - Abstract
Gene targeting using short interfering RNA (siRNA) has become a common strategy to explore gene function because of its prominent efficacy and specificity. For the application of siRNA technology to gene therapy, however, still more efficient transduction of siRNA into target cells is needed. In this study, we developed an adenoviral vector harboring a tandem-type siRNA expression unit, in which sense and antisense strands composing the siRNA duplex were separately transcribed by two human U6 promoters. Targeting survivin, an antiapoptotic molecule widely overexpressed in malignancies but not detected in terminally differentiated adult tissues, this type of adenoviral vector (Adv-siSurv) successfully exerted a gene knockdown effect and induced apoptosis in HeLa, U251, and MCF-7 cells. These cancer cells, once infected with Adv-siSurv, displayed remarkably attenuated growth potential, both in vitro and in vivo. Moreover, intratumoral injection of Adv-siSurv significantly suppressed tumor growth in a xenograft model using U251 glioma cells. This novel modality may be a promising tool for cancer therapy.
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- 2004
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41. BDNF Gene-Modified Mesenchymal Stem Cells Promote Functional Recovery and Reduce Infarct Size in the Rat Middle Cerebral Artery Occlusion Model
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Osamu Honmou, Kazunori Kato, Takashi Tamiya, Katsunori Sasaki, Hiroaki Uchida, Masayoshi Kobune, Kiminori Nakamura, Yutaka Kawano, Isao Date, Kiyohiro Houkin, Yoshinori Ito, Hirofumi Hamada, Sachie Hirai, and Kazuhiko Kurozumi
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Stromal cell ,medicine.medical_treatment ,Genetic enhancement ,Genetic Vectors ,Ischemia ,DNA Fragmentation ,Pharmacology ,Mesenchymal Stem Cell Transplantation ,Adenoviridae ,Drug Discovery ,Genetics ,Animals ,Humans ,Medicine ,Molecular Biology ,business.industry ,Cerebral infarction ,Brain-Derived Neurotrophic Factor ,Mesenchymal stem cell ,Infarction, Middle Cerebral Artery ,Mesenchymal Stem Cells ,Genetic Therapy ,Anatomy ,Transfection ,medicine.disease ,Magnetic Resonance Imaging ,Rats ,Disease Models, Animal ,Phenotype ,Cytokine ,medicine.anatomical_structure ,Molecular Medicine ,Bone marrow ,business - Abstract
Examination of the clinical therapeutic efficacy of using bone marrow stromal cells, including mesenchymal stem cells (MSC), has recently been the focus of much investigation. MSC were reported to ameliorate functional deficits after stroke in rats, with some of this improvement possibly resulting from the action of cytokines secreted by these cells. To enhance such cytokine effects, we transfected telomerized human MSC with the BDNF gene using a fiber-mutant F/RGD adenovirus vector and investigated whether these cells contributed to improved functional recovery in a rat transient middle cerebral artery occlusion (MCAO) model. BDNF production by MSC-BDNF cells was 23-fold greater than that seen in uninfected MSC. Rats that received MSC-BDNF showed significantly more functional recovery than did control rats following MCAO. Specifically, MRI analysis revealed that the rats in the MSC-BDNF group exhibited more significant recovery from ischemia after 7 and 14 days. The number of TUNEL-positive cells in the ischemic boundary zone was significantly smaller in animals treated with MSC-BDNF compared to animals in the control group. These data suggest that MSC transfected with the BDNF gene may be useful in the treatment of cerebral ischemia and may represent a new strategy for the treatment of stroke.
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- 2004
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42. Increased expansion of Valpha24+ T cells derived from G-CSF-mobilized peripheral blood stem cells as compared to peripheral blood mononuclear cells following alpha-galactosylceramide stimulation
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Sachiyo Kanai, Kazunori Kato, Yoshinori Ikarashi, Yoichi Takaue, Kazuo Shirakawa, Rumiko Asada-Mikami, Hiro Wakasugi, Yukie Harada, Tatsuo Abe, and Yuji Heike
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Cancer Research ,T-Lymphocytes ,medicine.medical_treatment ,T cell ,Lipopolysaccharide Receptors ,Bone Marrow Cells ,Galactosylceramides ,Cell Separation ,Granulocyte ,Biology ,Peripheral blood mononuclear cell ,Immunophenotyping ,Neoplasms ,Granulocyte Colony-Stimulating Factor ,medicine ,Humans ,Cells, Cultured ,Hematopoietic Stem Cell Transplantation ,General Medicine ,T lymphocyte ,Integrin alphaV ,Hematopoietic Stem Cells ,Molecular biology ,Hematopoietic Stem Cell Mobilization ,Recombinant Proteins ,Granulocyte colony-stimulating factor ,medicine.anatomical_structure ,Cytokine ,Oncology ,Cell culture ,Immunology ,Leukocytes, Mononuclear ,Stem cell - Abstract
In the present study, unpurified peripheral blood mononuclear cells (PBMCs) from various sources, including steady-state blood (normal donors) and granulocyte colony-stimulating factor (G-CSF)-mobilized blood (cancer patients and normal donors) (G-PBSC), were cultured in RPMI-1640 in the presence of IL-2 and alpha-galactosylceramide (alpha-GalCer) to expand V alpha 24(+) T cells, and their expansion kinetics were compared. G-CSF-mobilized cells showed markedly higher expansion potential (350-fold expansion of V alpha 24(+) T cells, regardless of whether the cells were from cancer patients or normal donors) than steady-state cells (15-fold expansion, compared to the initial inoculums) (n = 5, P < 0.01). We also confirmed that the CD14(-) fraction of G-PBSCs contained a large number of precursors of V alpha 24(+) T cells, compared to PBSCs, as well as a large number of CD14(+) cells, which assist V alpha 24(+) T cell proliferation. Our simple and practical procedure, which eliminates complicated cell manipulation (including cell purification), produces efficient expansion of V alpha 24(+) T cells when G-CSF-mobilized blood cells are cultured with alpha-GalCer.
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- 2003
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43. Injection Molding of Polystyrene Matrix Composites Filled with Vapor Grown Carbon Fiber
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Naoto Ohtake, Kazuki Enomoto, Toshiyuki Yasuhara, and Kazunori Kato
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Materials science ,Mechanical Engineering ,Carbon fibers ,Carbon nanotube ,Molding (process) ,law.invention ,Matrix (chemical analysis) ,chemistry.chemical_compound ,chemistry ,law ,Electrical resistivity and conductivity ,visual_art ,Ultimate tensile strength ,visual_art.visual_art_medium ,General Materials Science ,Polystyrene ,Composite material ,Elastic modulus - Abstract
Vapor grown carbon fiber (VGCF) is a kind of carbon nanotube (CNT), which has outstanding properties such as high mechanical strength and high electrical conductivity. In this study, injection molding properties of polystryrene (PS) filled with VGCF and evaluation of mechanical and electrical properties are discussed in comparison with composites in which conventional carbon fillers were filled. As a result, volume resistivity of VGCF/PS composites dropped significantly between VGCF concentration of 3 and 4 vol.%. Resistivity of the composites filled with VGCF was 1.2 × 10 2 Ω.cm when CGCF concentration was 11.6 vol.%. The resistivity was significantly lower than that of composites which were filled with conventional carbon fillers. The elastic modulus slightly increases with increasing VGCF concentration. whereas the tensile strength slightly decreases in the VGCF concentration in the range from 0 to 12 vol.%.
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- 2003
44. Sequence variability in the mitochondrial DNA control region of five Sebastes species
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Kazunori Kato and Masahito Higuchi
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Genetics ,Mitochondrial DNA ,Rockfish ,Effective population size ,Haplotype ,Nucleic acid sequence ,Zoology ,Genetic variability ,Sebastes ,Aquatic Science ,Biology ,biology.organism_classification ,Nucleotide diversity - Abstract
Sequence variability of the control region of mitochondrial DNA in five Sebastes species (S. thompsoni, S. joyneri, S. inermis, S. schlegeli and S. owstoni) was investigated. Of 324 nucleotide sites in the control region of S. thompsoni, 56 sites (17.3%) varied, and all 20 individuals had different haplotypes. The other four species had between five and 17 sites (1.5–5.9%), which was fewer than that observed in S. thompsoni. The nucleotide diversity of S. thompsoni was highest (3.45%) among the five species, and that of S. schlegeli was the lowest (0.19%). The results demonstrated that sequence variability exists in the control region of the five Sebastes fishes investigated, and that sequence data in the control region may be suitable for stock structure analysis. Also, the extent of genetic variablitiy in the control region differed among these species. In particular, the mitochondrial DNA control region in S. thompsoni was characterized by high sequence variability, which may indicate a large effective population size.
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- 2002
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45. U1B3.3 monoclonal antibody recognizes a precursor of NK1.1+ cytotoxic T cells generated by interleukin-2
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Kazunori Kato, Yoshinori Ikarashi, Mitsuzi Yoshida, and Hiro Wakasugi
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Chemistry ,T cell ,General Physics and Astronomy ,General Medicine ,Natural killer T cell ,Molecular biology ,Interleukin 21 ,medicine.anatomical_structure ,Interleukin 12 ,medicine ,Cytotoxic T cell ,IL-2 receptor ,General Agricultural and Biological Sciences ,Antigen-presenting cell ,Interleukin 3 - Abstract
U1B3.3 monoclonal antibody (mAb) was established by immunizing a rat with the tMK-2U lymphoma cell line, derived from athymic nude mice. U1B3.3 mAb recognizes some T cell populations, B cells and natural killer (NK) cells. U1B3.3+ T cells express CD3/T cell receptor (TCR) complex at a unique intensity: between that of TCR-intermediate cells (TCRint cells) and TCRbright cells. TCRint cells strongly express the interleukin-2 receptor β chain (IL-2Rβ), but almost all U1B3.3+ T cells express high or low levels of IL-2Rβ. When purified U1B3.3+ NK1.1-T cells were cultured with IL-2, approximately 14% of the cells acquired expression of NK1.1 molecules, which are expressed on NK cells and natural killer T (NKT) cells. Furthermore, U1B3.3+ NK1.1-T cells killed tumor cells after culture with IL-2. These results indicate that U1B3.3 mAb recognizes a precursor of NK1.1+ cytotoxic T cells generated by IL-2.
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- 2002
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46. 636 Transcription Mechanism of Minute Surface Pattern in Injection Molding
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Hiroshi Imamura, Naoto Ohtake, Toshiyuki Yasuhara, and Kazunori Kato
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Engineering ,Mechanism (biology) ,business.industry ,Mechanical engineering ,Molding (process) ,Transcription (software) ,business ,Cell biology ,Surface pattern - Published
- 2002
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47. Trapping and proliferation of target cells on C60 fullerene nano fibres
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Hideki Sasaki, Shunji Kurosu, Toru Maekawa, Seiki Iwai, and Kazunori Kato
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Materials science ,medicine.medical_treatment ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Nanomaterials ,medicine ,Nanotechnology ,Molecule ,lcsh:Social sciences (General) ,lcsh:Science (General) ,chemistry.chemical_classification ,Multidisciplinary ,biology ,Cell adhesion molecule ,Biomolecule ,Growth factor ,021001 nanoscience & nanotechnology ,Fluorescence ,Primary and secondary antibodies ,0104 chemical sciences ,chemistry ,Biochemistry ,biology.protein ,Biophysics ,lcsh:H1-99 ,Antibody ,0210 nano-technology ,Biotechnology ,lcsh:Q1-390 - Abstract
The ratio of the surface area to the volume of materials increases in inverse proportion to their size and therefore the surface area of nanostructures and nanomaterials is extremely large compared to that of macroscopic materials of the same volume, thanks to which it is supposed that chemical and biochemical reactions may be greatly enhanced and target molecules and cells may be efficiently trapped on the surface of nanomaterials. It is well known that C60 molecules are stable both physically and chemically and the affinity of C60 molecules with biomolecules is rather high. Here, we synthesise fibres composed of C60 and sulphur and immobilise the surface of the fibres with the primary antibody; i.e., epithelial cell adhesion molecules (anti-EpCAM), to trap target cells. The primary antibody is evenly immobilised on the fibres confirmed by a fluorescent secondary antibody attached to the primary one and then TE2 esophageal and DLD-1 colon cancer cells are successfully trapped by the primary antibody immobilised on the fibres thanks to its high affinity with TE2 and DLD-1 cells, whereas few IM9 B lymphoblast cells are captured on the fibres since the affinity of the primary antibody with IM9 cells is extremely low. Furthermore, those cells trapped by the primary antibody immobilised on the fibres proliferate faster than native cells thanks to the primary antibody acting as a growth factor. The present result suggests that different types of cells can be trapped and grown on nano fibres by immobilising appropriate antibody molecules on the surface of the fibres. Even an extremely small number of cells in sample fluids may be analysed and characterised for the detection of diseases such as cancer in the early stage by trapping and proliferating target cells on the fibres.
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- 2017
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48. T-cell-conditioned medium efficiently induces the maturation and function of human dendritic cells
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Yoichi Takaue, Hiro Wakasugi, and Kazunori Kato
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CD3 Complex ,T-Lymphocytes ,T cell ,CD40 Ligand ,Immunology ,Cell ,Antigen presentation ,Cell Communication ,Interferon-gamma ,Immune system ,medicine ,Humans ,Immunology and Allergy ,Cells, Cultured ,Antigen Presentation ,CD40 ,biology ,Tumor Necrosis Factor-alpha ,Cell Differentiation ,Dendritic Cells ,Cell Biology ,Ligand (biochemistry) ,Phenotype ,Cell biology ,medicine.anatomical_structure ,Culture Media, Conditioned ,biology.protein ,Antibody - Abstract
We present evidence that T-cell-conditioned media (TCCM) can efficiently induce human immature dendritic cells (DC) to express high levels of immune accessory molecules commonly found on mature DC. TCCM prepared from cell-free supernatants of anti-CD3-activated T cells contained several soluble factors including CD40-ligand (sCD40L), TNF-α, and IFN-γ. In contrast to moderate up-regulation of costimulatory molecules by the addition of individual cytokines or monocyte-conditioned medium, treatment of immature DC with TCCM induced a marked increase in the expression of costimulatory molecules in a dose-dependent manner. The ability of TCCM to induce such phenotypic changes could be abrogated by neutralizing antibodies specific for CD40L, TNF-α, and IFN-γ, indicating that these factors present in TCCM are mainly implicated in the maturation of DC. Importantly, TCCM-treated DC can produce significantly higher levels of IL-12 and are highly effective stimulators in allogenenic and autologous mixed-lymphocyte reactions. Overall, these findings show that cultivation with TCCM is an efficient approach for the induction of mature DC that should be useful in eliciting antigen-specific immune responses against cancer and viruses.
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- 2001
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49. Analysis of stress distribution in caliber rolling by the energy method using finite-element division
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Kazutake Komori and Kazunori Kato
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Engineering ,business.industry ,Work (physics) ,Grid method multiplication ,Flow (psychology) ,Mathematical analysis ,Metals and Alloys ,Structural engineering ,Stress distribution ,Plasticity ,Division (mathematics) ,Industrial and Manufacturing Engineering ,Finite element method ,Computer Science Applications ,Physics::Fluid Dynamics ,Caliber ,Modeling and Simulation ,Ceramics and Composites ,business - Abstract
The authors previously proposed an energy method using finite-element division and applied it to the analysis of the flow of material. In this work, the authors develop this method further to obtain the stress distribution in caliber rolling. Recently, Tomita obtained the stress distribution using the grid method so that the equilibrium condition may be satisfied approximately, whereas Mori evaluated the accuracy of the result obtained by the rigid-plastic finite-element method, by considering the equivalent nodal force which is assumed to be in equilibrium. Hence, the authors combined these methods and applied them to determine the stress distribution. The following results were obtained. First, in the flat rolling of bars, the roll force agrees well with the theoretical equation proposed by Saito. Second, in square-diamond rolling and round-oval rolling, the roll force depends on the ratio of the indirectly reduced area in the cross-section to the area of the cross-section. Finally, in square-oval rolling, the roll force agrees with the theoretical equation proposed by Saito when the projected material-roll contact length is replaced by the mean projected material-roll contact length in the width direction.
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- 2001
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50. Melt front surface asperity and welding-defect generation in ceramic injection molding
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Y.H. Chung, Naoto Otake, and Kazunori Kato
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Materials science ,Flow (psychology) ,Metals and Alloys ,Weld line ,Welding ,Surface finish ,Molding (process) ,Industrial and Manufacturing Engineering ,Computer Science Applications ,law.invention ,law ,Modeling and Simulation ,visual_art ,Ceramics and Composites ,Welding defect ,visual_art.visual_art_medium ,Ceramic ,Composite material ,Asperity (materials science) - Abstract
Melt front roughness was examined firstly, and it was found that an injected part is separated into two regions: a rough surface region and a fine surface region. The rough surface region results from melt front asperities generated by the blowout of voids at the front surface which are mixed into the material by jetting flow in the sprue. It was also found that voids in the sprue can be eliminated by applying counter-pressure. Secondly, the generation property of welding defects, weld line and voids, has been examined by counter-flow joining and their elimination criteria are obtained. It was shown that both criteria approximately coincide with each other. The welding-defect elimination criterion obtained is applied to the evaluation of welding-defect generation under various injection conditions and it was found that the criterion does not depend greatly on the asperities of the flow front. Furthermore, the criterion is also effective for estimating welding defects in injection molding using a mold cavity with inserts. Finally, it was confirmed that the above criterion approximately coincides with that in a previous paper which was obtained by the use of simple void-reducing conditions in the joining of green ceramic blocks with artificially grooved surfaces.
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- 2001
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