Seisuke Okazawa
University of Toyama
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Featured researches published by Seisuke Okazawa.
Respirology | 2013
Tomomi Ichikawa; Ryuji Hayashi; Kensuke Suzuki; Shingo Imanishi; Kenta Kambara; Seisuke Okazawa; Minehiko Inomata; Toru Yamada; Yu Yamazaki; Yukiko Koshimizu; Toshiro Miwa; Shoko Matsui; Isao Usui; Masaharu Urakaze; Yuji Matsuya; Masakiyo Sasahara; Kazuyuki Tobe
Background and objective: In asthma, reduced histone deacetylase activity and enhanced histone acetyltransferase activity in the lungs have been reported. However, the precise function of Sirtuin 1 (Sirt1), a class III histone deacetylase, and the effect of the Sirt1 activator SRT1720 on allergic inflammation have not been fully elucidated.
PLOS ONE | 2013
Seisuke Okazawa; Yukihiro Furusawa; Ayako Kariya; Mariame A. Hassan; Mie Arai; Ryuji Hayashi; Yoshiaki Tabuchi; Takashi Kondo; Kazuyuki Tobe
The inhibition of DNA damage response pathway seems to be an attractive strategy for cancer therapy. It was previously reported that in rodent cells exposed to heat stress, cell growth was promoted by the activity of DNA-dependent protein kinase (DNA-PK), an enzyme involved in DNA non-homologous end joining (NHEJ) required for double-strand break repair. The absence of a functioning DNA-PK was associated with down regulation of heat shock protein 70 (HSP70). The objective of this study is thus to investigate the role of DNA-PK inhibition in heat-induced apoptosis in human cell lines. The inhibitors of phosphorylation of the DNA-PK catalytic subunit (DNA-PKcs) at Ser2056, such as NU7026 and NU7441, were utilized. Furthermore, knock down of DNA-PKcs was carried out using small interfering RNA (siDNA-PKcs). For heat exposure, cells were placed in water bath at 44°C for 60 min. Apoptosis was evaluated after 24 h incubation flow cytometrically. Proteins were extracted after 24 h and analyzed for HSP70 and HSP40 expression by Western blotting. Total RNA was extracted 6 h after treatment and analyzed using a GeneChip® microarray system to identify and select the up-regulated genes (≥1.5 fold). The results showed an enhancement in heat-induced apoptosis in absence of functioning DNA-PKcs. Interestingly, the expression levels of HSP70 and HSP40 were elevated in the absence of DNA-PKcs under heat stress. The results of genetic network analysis showed that HSPs and JUN genes were up-regulated independently of DNA-PKcs in exposed parent and knock out cells. In the presence of functioning DNA-PKcs, there was an observed up-regulation of anti-apoptotic genes, such as NR1D1, whereas in the absence of DNA-PKcs the pro-apoptotic genes, such as EGR2, were preferentially up-regulated. From these findings, we concluded that in human cells, the inactivation of DNA-PKcs can promote heat-induced apoptosis independently of heat-shock proteins.
Endocrine Journal | 2015
Yasuko Hayashikawa; Minoru Iwata; Minehiko Inomata; Yukio Kawagishi; Kotaro Tokui; Chihiro Taka; Kenta Kambara; Seisuke Okazawa; Toru Yamada; Ryuji Hayashi; Yutaka Kamura; Teruyo Okazawa; Shoko Matsui; Mika Kigawa; Kazuyuki Tobe
Conflicting findings have been reported regarding the role of adiponectin in asthma. The aim of this study was to evaluate the association of adiponectin with pulmonary functions and asthma in the Japanese population. First, among a general population that participated in a previous study (group 1), we selected 329 subjects after excluding those with asthma, chronic obstructive pulmonary disease, and a smoking history and examined the associations of the serum total adiponectin levels with pulmonary functions. In a second cohort (group 2) consisting of 61 asthmatic patients and 175 control non-asthmatic subjects, we examined the associations between asthma and the levels of total, high (HMW), middle (MMW) and low (LMW) molecular weight adiponectin isoforms as well as the ratio of each isoform to total adiponectin level. Although the total adiponectin levels were not significantly different between the asthmatic and control subjects in group 2, the levels were significantly and positively associated with the forced expiratory volume in 1 s after adjustments for confounding factors (P < 0.05) in women in group 1. In group 2, the LMW adiponectin level was significantly higher and the MMW/total adiponectin ratio was significantly lower among the asthmatic subjects than among the control subjects after adjustments for confounding factors in both sexes (P < 0.05). The present study showed that a low total adiponectin level may lead to airway narrowing compatible with asthmatic airways in women, and higher LMW adiponectin levels and lower MMW/total adiponectin ratio are significantly associated with current asthma in both sexes.
Journal of Diabetes Investigation | 2012
Minehiko Inomata; Yukio Kawagishi; Chihiro Taka; Kenta Kambara; Seisuke Okazawa; Yasuo Fukushima; Shingo Imanishi; Tomomi Ichikawa; Kensuke Suzuki; Toru Yamada; Yutaka Kamura; Chikaaki Kobashi; Minoru Iwata; Shigeki Sumi; Hideki Origasa; Ryuji Hayashi; Kazuyuki Tobe
Aims/Introduction: It has been reported that metabolic syndrome is associated with impaired lung function, and abdominal obesity is regarded as the most important determinant of this association. We evaluated the association between a component of metabolic syndrome, indices of body composition, including the total adipose tissue content, lean bodyweight and visceral adipose tissue content, as assessed by bioimpedance analysis, and lung function.
Tumori | 2014
Minehiko Inomata; Ryuji Hayashi; Kotaro Tokui; Chihiro Taka; Seisuke Okazawa; Kenta Kambara; Shingo Imanishi; Kensuke Suzuki; Toru Yamada; Toshiro Miwa; Tatsuhiko Kashii; Shoko Matsui; Kazuyuki Tobe
Aims and Background It is reported that about 20% of patients with small cell lung cancer (SCLC) receive third-line chemotherapy. We conducted a retrospective study to investigate the outcome and prognostic factors of patients with SCLC who receive third-line chemotherapy. Methods and Study Design The medical records of patients with SCLC who received third-line chemotherapy at our institution were reviewed. Overall survival (OS) from the initiation of third-line chemotherapy was evaluated, and the association between OS and patient characteristics was assessed by the log-rank test. Results A total of 73 patients with SCLC were treated with cytotoxic drugs between 2004 and 2012, and 19 patients received third-line chemotherapy. Median OS from initiation of third-line chemotherapy was 8.5 months. Patients with higher body mass index (BMI) (P = 0.0071), lower levels of lactate dehydrogenase (LDH) (P = 0.0036), higher levels of hemoglobin (P = 0.048), longer time to progression (TTP) from the initiation of second-line treatment (P = 0.0036), and better response to second-line treatment (P = 0.029) had longer duration of OS. Conclusions It is suggested that TTP and tumor response in second-line chemotherapy, serum levels of LDH and hemoglobin, and BMI at initiation of third-line chemotherapy could be possible prognostic factors.
Journal of International Medical Research | 2015
Kensuke Suzuki; Hideaki Furuse; Takeshi Tsuda; Yasuaki Masaki; Seisuke Okazawa; Kenta Kambara; Minehiko Inomata; Toshiro Miwa; Shoko Matsui; Tatsuhiko Kashii; Hirokazu Taniguchi; Ryuji Hayashi; Kazuyuki Tobe
Objective To determine whether the creatinine/cystatin C (Cr/CysC) ratio, which is influenced by muscle mass, can be used as a predictive marker of the adverse effects of chemotherapy. Methods This single-centre, retrospective, observational study assessed patients with lung cancer. Serum Cr and CysC levels were measured once within 1 month prior the commencement of chemotherapy. Results A total of 25 patients with lung cancer were enrolled in the study: 22 received first-line therapy; three received second-line therapy. A significant difference was noted regarding the Cr/CysC ratios between patients with nonsmall-cell lung cancer (NSCLC) and those with small-cell lung cancer (0.78 versus 0.92, respectively). A significant difference was also noted in the Cr/CysC ratios of patients with NSCLC with toxicity grades <3 and ≥3 (0.84 versus 0.70, respectively). Similar findings were observed in patients with NSCLC who received platinum-based combination therapy (toxicity grade < 3, 0.85; toxicity grade ≥3, 0.69). Conclusion The Cr/CysC ratio could serve as a useful predictive marker for chemotherapy-related adverse effects in patients with NSCLC.
Journal of Medical Case Reports | 2012
Minehiko Inomata; Ryuji Hayashi; Kenta Kambara; Seisuke Okazawa; Shingo Imanishi; Tomomi Ichikawa; Kensuke Suzuki; Toru Yamada; Toshiro Miwa; Tatsuhiko Kashii; Shoko Matsui; Kazuyuki Tobe; Masakiyo Sasahara
IntroductionMiliary brain metastasis is an extremely rare form of brain metastasis which can present with atypical imaging findings. We report the case of a patient with miliary brain metastasis of lung cancer showing calcification in metastatic lesions.Case presentationA 68-year-old Japanese woman was diagnosed with lung adenocarcinoma. Brain computed tomography revealed multiple small calcified lesions in both cerebral hemispheres. Mutation of the epidermal growth factor receptor gene (exon 21, L858R) in lung cancer cells was detected, and treatment with gefitinib was initiated. A partial response was observed; however, the patient was readmitted to our hospital because of regrowth of the primary lesion and complaints of nausea, headache, and difficulty walking. Brain magnetic resonance imaging revealed scattered tiny nodules enhanced by gadolinium. A diagnosis of leptomeningeal carcinomatosis was made on the basis of cerebrospinal fluid cytology. The patient’s general status worsened, and she died 356 days after the day of first medical examination. Upon autopsy, the brain was found to be edematous and swollen. Lung carcinoma cells were diffusely disseminated on the meningeal surface. Metastatic foci of small nodular form, accompanied by calcifications, were also found in the brain parenchyma. We diagnosed miliary metastasis of lung carcinoma.ConclusionsTo the best of our knowledge, this is the third report of calcified miliary brain metastasis confirmed by autopsy. We describe calcified lesions that increased in size during the clinical course of nine months. Brain computed tomography findings that reveal multiple small calcified lesions in patients with malignancy should raise suspicion of miliary brain metastasis.
Tumori | 2016
Minehiko Inomata; Ryuji Hayashi; Kotaro Tokui; Chihiro Taka; Seisuke Okazawa; Kenta Kambara; Tomomi Ichikawa; Toru Yamada; Toshiro Miwa; Tatsuhiko Kashii; Shoko Matsui; Kazuyuki Tobe
Aims and Background Amrubicin monotherapy can be an effective treatment option for patients with recurrent small cell lung cancer (SCLC). We conducted this retrospective study to investigate the prognostic factors in patients with recurrent SCLC receiving amrubicin monotherapy. Methods The associations between survival and clinical data, including the performance status, body mass index (BMI), plasma lactate dehydrogenase (LDH) level, and plasma neuron-specific enolase level, were evaluated in patients with recurrent SCLC, and a subset analysis of patients with platinum-resistant disease was conducted. Results In all, 37 patients were evaluated. The median survival from the date of initiation of amrubicin monotherapy was 9.1 months (95% confidence interval 4.7–12.0 months). Multivariate analysis using a Cox proportional hazard model identified the plasma LDH level (p = 0.049), BMI (p = 0.031), and platinum resistance (p = 0.032) as independent factors associated with survival. The same associations were also observed in the subset of patients with platinum-resistant disease. Conclusions Our findings suggest that the plasma LDH level and BMI may be useful prognostic factors in patients with SCLC receiving amrubicin monotherapy, including patients with platinum-resistant disease.
Journal of Medical Case Reports | 2012
Kotaro Tokui; Yukio Kawagishi; Minehiko Inomata; Chihiro Taka; Seisuke Okazawa; Toru Yamada; Toshiro Miwa; Ryuji Hayashi; Shoko Matsui; Yasuo Takano; Kazuyuki Tobe
IntroductionChronic necrotizing pulmonary aspergillosis usually occurs in mildly immune-compromised hosts or those with underlying pulmonary disease. The radiographic pattern of chronic necrotizing pulmonary aspergillosis is typically a progressive upper lobe cavitary infiltrate with pleural thickening. We report here an atypical case of chronic necrotizing pulmonary aspergillosis mimicking lung cancer, which developed into a disseminated fatal disease in an older woman with no comorbidity.Case presentationAn 80-year-old Japanese woman was referred to our hospital for a chest roentgenogram abnormality. Repeated fiber-optic bronchoscopy could not confirm any definite diagnosis, and she refused further examinations. Considering the roentgenogram findings and her age, she was followed-up as a suspected case of lung cancer without any treatment. Then, 10 months later, she complained of visual disturbance and was admitted to our department of ophthalmology. She was diagnosed as having endophthalmitis. After treatment with corticosteroids for 20 days, she developed acute encephalitis and died four weeks later. Autopsy revealed dissemination of Aspergillus hyphae throughout her body, including her brain.ConclusionsIn older patients, even if they do not have any comorbidity, chronic necrotizing pulmonary aspergillosis should be added to the differential diagnosis of solitary pulmonary lesions in a chest roentgenogram.
Onkologie | 2017
Tomoaki Ikezaki; Kensuke Suzuki; Kenta Kambara; Minehiko Inomata; Seisuke Okazawa; Shinya Kajiura; Toshiro Miwa; Kouichi Tanabe; Tatsuhiko Kashii
Background: Approximately 70% of the patients who receive chemotherapy suffer from fatigue, which lowers their quality of life and also has a negative influence on therapeutic efficacy. Previous studies have suggested a relationship between blood carnitine levels and fatigue. We conducted a prospective observational study to examine the relationship between carnitine pharmacokinetics and chemotherapy-induced fatigue in patients receiving cancer chemotherapy regimens that include cisplatin. Patients and Methods: 11 patients receiving chemotherapy including cisplatin (60-80 mg/m2) were included in the study. We performed 24-h urine collections and took blood samples on day 1 (before the initiation of chemotherapy) and days 2, 3, 4, and 8 in order to measure the carnitine concentrations in the serum and urine. These were compared with measures of self-reported fatigue. The primary endpoint was the change in self-reported fatigue subscales from baseline to day 8. Results: Urinary carnitine concentrations differed significantly on days 2 and 3 (p = 0.003). The Functional Assessment of Chronic Illness Therapy-Fatigue scale version 4A score on day 8 indicated significantly higher levels of fatigue as compared to day 1 (p = 0.013). Conclusion: This study suggests that there is an association between urinary carnitine levels and self-reported fatigue.