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Dive into the research topics where Kengo Nagashima is active.

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Featured researches published by Kengo Nagashima.


Inflammation | 2012

A distinct regulatory role of Th17 cytokines IL-17A and IL-17F in chemokine secretion from lung microvascular endothelial cells.

Hitomi Fujie; Kaijun Niu; Michiru Ohba; Yoshihisa Tomioka; Haruki Kitazawa; Kengo Nagashima; Takashi Ohrui; Muneo Numasaki

Th17 cytokines IL-17A and IL-17F play a critical role in the activation and recruitment of neutrophils at airway inflammation mainly through the induction of CXC chemokines in the lungs. Vascular endothelial cells belong to the category of major CXC chemokine-producing cells. However, until now, the precise role of Th17 cytokines in CXC chemokine secretion in lung microvascular endothelial cells (LMVECs) has not been fully elucidated. In this study, we examined the biological effects of Th17 cytokines IL-17A and IL-17F on CXCL1, CXCL5, and CXCL8 release in LMVECs. Both IL-17 receptor A (IL-17RA) and IL-17RC are expressed on the surface of LMVECs. In contrast to IL-17F, IL-17A significantly upregulated CXCL1 mRNA expression and protein release, whereas both IL-17A and IL-17F did not have the ability to induce CXCL5 and CXCL8 secretion in LMVECs. IL-17A and IL-17F displayed positive regulatory effects on IL-1β-induced CXCL1, CXCL5, and CXCL8 secretion. On the other hand, IL-17A enhanced the upregulating effect of TNF-α on CXCL1, CXCL5, and CXCL8 release, whereas IL-17F had a negative regulatory effect on TNF-α-mediated secretion. Th2 cytokines IL-4 and IL-13 showed an inhibitory effect on IL-1β plus IL-17A-induced CXCL1, CXCL5, and CXCL8 secretion, but displayed a positive regulatory effect on TNF-α plus IL-17A-induced secretion. These results provide evidence that Th17 cytokines IL-17A and IL-17F have a distinct regulatory role in CXCL1, CXCL5, and CXCL8 expression in LMVECs stimulated either with IL-1β or with TNF-α. Our findings also suggest that CXC chemokine secretion in LMVECs may be complicatedly regulated by Th17 cytokines, Th2 cytokines, and macrophage-associated cytokines in pathological conditions such as bronchial asthma.


Sensors | 2012

Study Designs and Statistical Analyses for Biomarker Research

Masahiko Gosho; Kengo Nagashima; Yasunori Sato

Biomarkers are becoming increasingly important for streamlining drug discovery and development. In addition, biomarkers are widely expected to be used as a tool for disease diagnosis, personalized medication, and surrogate endpoints in clinical research. In this paper, we highlight several important aspects related to study design and statistical analysis for clinical research incorporating biomarkers. We describe the typical and current study designs for exploring, detecting, and utilizing biomarkers. Furthermore, we introduce statistical issues such as confounding and multiplicity for statistical tests in biomarker research.


PLOS ONE | 2015

Predictive Power of a Body Shape Index for Development of Diabetes, Hypertension, and Dyslipidemia in Japanese Adults: A Retrospective Cohort Study

Misuzu Fujita; Yasunori Sato; Kengo Nagashima; Sho Takahashi; Akira Hata

Background/Objectives Recently, a body shape index (ABSI) was reported to predict all-cause mortality independently of body mass index (BMI) in Americans. This study aimed to evaluate whether ABSI is applicable to Japanese adults as a predictor for development of diabetes, hypertension, and dyslipidemia. Subjects/Methods We evaluated the predictive power of ABSI in a retrospective cohort study using annual health examination data from Chiba City Hall in Japan, for the period 2008 to 2012. Subjects included 37,581 without diabetes, 23,090 without hypertension, and 20,776 without dyslipidemia at baseline who were monitored for disease incidence for 4 years. We examined the associations of standardized ABSI, BMI, and waist circumference (WC) at baseline with disease incidence by logistic regression analyses. Furthermore, we conducted a case-matched study using the propensity score matching method. Results Elevated BMI, WC, and ABSI increased the risks of diabetes and dyslipidemia [BMI-diabetes: odds ratio (OR) = 1.26, 95% confidence interval (95%CI) = 1.20−1.32; BMI-dyslipidemia: OR = 1.15, 95%CI = 1.12−1.19; WC-diabetes: OR = 1.24, 95%CI = 1.18−1.31; WC-dyslipidemia: OR = 1.15, 95%CI = 1.11−1.19; ABSI-diabetes: OR = 1.06, 95%CI = 1.01−1.11; ABSI-dyslipidemia: OR = 1.04, 95%CI = 1.01−1.07]. Elevated BMI and WC, but not higher ABSI, also increased the risk of hypertension [BMI: OR = 1.32, 95%CI = 1.27−1.37; WC: OR = 1.22, 95%CI = 1.18−1.26; ABSI: OR = 1.00, 95%CI = 0.97−1.02]. Areas under the curve (AUCs) in regression models with ABSI were significantly smaller than in models with BMI or WC for all three diseases. In case-matched subgroups, the power of ABSI was weaker than that of BMI and WC for predicting the incidence of diabetes, hypertension, and dyslipidemia. Conclusions Compared with BMI or WC, ABSI was not a better predictor of diabetes, hypertension, and dyslipidemia in Japanese adults.


Lancet Neurology | 2016

Safety and efficacy of thalidomide in patients with POEMS syndrome: a multicentre, randomised, double-blind, placebo-controlled trial

Sonoko Misawa; Yasunori Sato; Kanako Katayama; Kengo Nagashima; Reiko Aoyagi; Yukari Sekiguchi; Gen Sobue; Haruki Koike; Ichiro Yabe; Hidenao Sasaki; Osamu Watanabe; Hiroshi Takashima; Masatoyo Nishizawa; Izumi Kawachi; Susumu Kusunoki; Yoshiyuki Mitsui; Seiji Kikuchi; Ichiro Nakashima; Shu-ichi Ikeda; Nobuo Kohara; Takashi Kanda; Jun-ichi Kira; Hideki Hanaoka; Satoshi Kuwabara

BACKGROUND Polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome is a rare cause of demyelinating neuropathy, with multi-organ involvement characterised by plasma cell dyscrasia and VEGF overproduction. No treatments have been established for patients with POEMS syndrome who are not eligible for stem-cell transplantation. Thalidomide suppresses VEGF and plasma cell proliferation. We aimed to assess the safety and efficacy of thalidomide for the treatment of POEMS syndrome. METHODS We did a randomised, double-blind, placebo-controlled, phase 2/3 trial at 12 hospitals in Japan. Adults (age ≥20 years) with POEMS syndrome who were ineligible for autotransplantation were randomly assigned (1:1) by a minimisation method to treatment with oral dexamethasone (12 mg/m(2) per day on the first 4 days of every 28-day cycle) plus either oral thalidomide (200 mg daily) or placebo for six cycles. All study personnel and patients were masked to treatment allocation. The primary endpoint was the reduction rate of serum VEGF concentrations at 24 weeks. Analysis was by intention to treat. This study is registered with the UMIN Clinical Trials Registry, UMIN000004179. FINDINGS Between Nov 11, 2010, and July 3, 2014, we randomly assigned 25 patients to receive either thalidomide (n=13) or placebo (n=12); one patient in the placebo group was excluded from analyses because of a protocol violation. The adjusted mean VEGF concentration reduction rate at 24 weeks was 0·39 (SD 0·34) in the thalidomide group compared with -0·02 (0·54) in the placebo group (adjusted mean difference 0·41, 95% CI 0·02-0·80; p=0·04). Mild sinus bradycardia was more frequent in the thalidomide group than in the placebo group (seven [54%] vs zero; p=0·006). Five patients had serious adverse events: three in the thalidomide group (transient cardiac arrest, heart failure, and dehydration) and two in the placebo group (ileus and fever). No deaths occurred during the randomised study. In the 48-week open-label study period (n=22), newly developed adverse events were sinus bradycardia (n=4), constipation (n=5), and mild sensory neuropathy (n=5). Two patients died in the open-label study; both patients were initially in the placebo group, and the cause of death was progression of the disease. INTERPRETATION Thalidomide reduces serum VEGF concentrations and represents a new treatment for patients with POEMS syndrome who are not eligible for stem-cell transplantation. Thalidomide treatment poses a risk of bradycardia; however, the benefits are likely to exceed the risk. FUNDING Japanese Ministry of Health, Labour, and Welfare, and Fujimoto Pharmaceuticals.


BMJ Open | 2015

Study protocol for a phase III multicentre, randomised, open-label, blinded-end point trial to evaluate the efficacy and safety of immunoglobulin plus cyclosporin A in patients with severe Kawasaki disease (KAICA Trial)

Reiko Aoyagi; Hiromichi Hamada; Yasunori Sato; Hiroyuki Suzuki; Yoshihiro Onouchi; Ryota Ebata; Kengo Nagashima; Moe Terauchi; Masaru Terai; Hideki Hanaoka; Akira Hata

Introduction Kawasaki disease (KD) is an acute, self-limited vasculitis of unknown aetiology that predominantly affects infants and young children. We hypothesise that cyclosporin A (CsA) may be effective in treating KD by regulating the Ca2+/NFAT signalling pathway. This trial compares the current standard therapy of intravenous immunoglobulin (IVIG) and the combined IVIG+CsA therapy in paediatric patients with severe KD. Methods and analysis This trial is a phase III, multicentre, randomised, open-label, blinded-end point trial that evaluates the efficacy and safety of IVIG+CsA therapy. Patients with severe KD who satisfy the eligibility criteria are randomised (1:1) to receive either CsA (5 mg/kg/day for 5 days; Neoral) plus high-dose IVIG (2 g/kg for 24 h and aspirin 30 mg/kg/day), or high-dose IVIG alone (2 g/kg for 24 h and aspirin 30 mg/kg/day). The primary end point is the frequency of occurrence of coronary artery abnormalities during the trial period. An independent end point review committee will be in charge of the trial assessment. Ethics and dissemination The protocol was approved by the Institutional Review Board of each institution. The trial was notified and registered at the Pharmaceutical and Medical Devices Agency, in Japan. The trial is currently on-going and is scheduled to finish in April 2017. The findings will be disseminated through peer-reviewed publications and conference presentations. Trial registration number JMA-IIA00174; Pre-results.


Journal of Ultrasound in Medicine | 2016

Quantitative Ultrasound Elastography With an Acoustic Coupler for Achilles Tendon Elasticity: Measurement Repeatability and Normative Values.

Yohei Yamamoto; Satoshi Yamaguchi; Takahisa Sasho; Taisuke Fukawa; Yorikazu Akatsu; Kengo Nagashima; Kazuhisa Takahashi

The purposes of this study were to measure intraobserver and interobserver repeatability of quantitative elastography using an acoustic coupler for the Achilles tendon, to compare elastographic values among different age groups, and to assess the correlation between quantitative and conventional qualitative measurements.


Cancer Science | 2012

Nucleostemin and TWIST as predictive markers for recurrence after neoadjuvant chemotherapy for esophageal carcinoma

Takako Eguchi Nakajima; Hiroshi Yoshida; Naoko Okamoto; Kengo Nagashima; Hirokazu Taniguchi; Yasuhide Yamada; Tadakazu Shimoda; Kenkichi Masutomi

We recently demonstrated that overexpression of the nucleolar GTP‐binding protein nucleostemin drives the fraction of genetically‐defined tumor cells that exhibit markers and tumorigenic properties of tumor initiating cells. More specifically, cells that constitutively express elevated levels of nucleostemin exhibit increased TWIST expression; expression of genes that induced pluripotent stem cells; enhanced radioresistance; tumor formation, even when small numbers of cells are implanted; and an increased propensity to metastasize. An immunohistochemical analysis of cancer stem cell markers, such as nucleostemin and TWIST has not been conducted in surgically‐resected esophageal squamous cell carcinomas after neoadjuvant chemotherapy. In the present study, we examined the expression of CD133, CD44, nucleostemin, guanine nucleotide‐binding protein‐like 3‐like, and TWIST by immunohistochemistry in a series of 54 surgically‐resected specimens of esophageal squamous cell carcinomas after neoadjuvant chemotherapy. We identified that high nucleostemin proportion, TWIST intensity, and advanced pathological N stage were significantly correlated with poor relapse‐free survival. Together, these observations imply nucleostemin and TWIST as the predictive markers for postoperative recurrence. (Cancer Sci 2012; 103: 233–238)


Journal of Oncology Practice | 2011

Characteristics and Outcomes of Patients With Advanced Gastric Cancer Who Declined to Participate in a Randomized Clinical Chemotherapy Trial

Chiharu Tanai; Takako Eguchi Nakajima; Kengo Nagashima; Ken Kato; Tetsuya Hamaguchi; Yasuhide Yamada; Kei Muro; Kuniaki Shirao; Hideo Kunitoh; Yasuhiro Matsumura; Seiichiro Yamamoto; Yasuhiro Shimada

PURPOSE There is insufficient data to verify whether participation in clinical trials in itself can lead to better clinical outcomes. We have analyzed the characteristics and outcomes of patients who declined to participate in a randomized trial in comparison with those who participated in the trial. PATIENTS AND METHODS A randomized trial for naive advanced gastric cancer was offered to 286 patients. The trial investigated the superiority of irinotecan plus cisplatin and the noninferiority of S-1 compared with continuous fluorouracil infusion. We retrospectively reviewed the characteristics and outcomes for both participants and nonparticipants in this trial. RESULTS Of the 286 patients, 98 (34%) declined to participate in the trial. The rate of declining was significantly higher among younger patients (P = .003), and it varied significantly between attending physicians (range, 23% to 58%; P = .004). There were no other significant correlations between rate of declining and patient characteristics. No significant differences were observed in the clinical outcomes between the participants and nonparticipants, for whom the median survival times were 367 versus 347 days, respectively. The hazard ratio for overall survival, adjusted for other confounding variables, was 1.21 (95% CI, 0.91 to 1.60). No interaction was observed between participation and the various regimens. CONCLUSION There was no difference in clinical outcomes between participants and nonparticipants. However, the patients age and the doctor-patient relationship may have an effect on patient accrual to randomized trials.


Pharmacogenomics Journal | 2009

A new statistical screening approach for finding pharmacokinetics-related genes in genome-wide studies

Yasunori Sato; Nan M. Laird; Kengo Nagashima; R Kato; T Hamano; A Yafune; N Kaniwa; Yoshiro Saito; E Sugiyama; S-R Kim; J Furuse; H Ishii; H Ueno; T Okusaka; N Saijo; J-i Sawada; Teruhiko Yoshida

Biomedical researchers usually test the null hypothesis that there is no difference of the population mean of pharmacokinetics (PK) parameters between genotypes by the Kruskal–Wallis test. Although a monotone increasing pattern with a number of alleles is expected for PK-related genes, the Kruskal–Wallis test does not consider a monotonic response pattern. For detecting such patterns in clinical and toxicological trials, a maximum contrast method has been proposed. We show how that method can be used with pharmacogenomics data to a develop test of association. Further, using simulation studies, we compare the power of the modified maximum contrast method to those of the maximum contrast method and the Kruskal–Wallis test. On the basis of the results of those studies, we suggest rules of thumb for which statistics to use in a given situation. An application of all three methods to an actual genome-wide pharmacogenomics study illustrates the practical relevance of our discussion.


PLOS ONE | 2016

Income Related Inequality of Health Care Access in Japan: A Retrospective Cohort Study.

Misuzu Fujita; Yasunori Sato; Kengo Nagashima; Sho Takahashi; Akira Hata

The purpose of this retrospective cohort study was to analyze the association between income level and health care access in Japan. Data from a total of 222,259 subjects (age range, 0–74 years) who submitted National Health Insurance claims in Chiba City from April 2012 to March 2014 and who declared income for the tax period from January 1 to December 31, 2012 were integrated and analyzed. The generalized estimating equation, in which household was defined as a cluster, was used to evaluate the association between equivalent income and utilization and duration of hospitalization and outpatient care services. A significant positive linear association was observed between income level and outpatient visit rates among all age groups of both sexes; however, a significantly higher rate and longer period of hospitalization, and longer outpatient care, were observed among certain lower income subgroups. To control for decreased income due to hospitalization, subjects hospitalized during the previous year were excluded, and the data was then reanalyzed. Significant inverse associations remained in the hospitalization rate among 40–59-year-old men and 60–69-year-old women, and in duration of hospitalization among 40–59 and 60–69-year-olds of both sexes and 70–74-year-old women. These results suggest that low-income individuals in Japan have poorer access to outpatient care and more serious health conditions than their higher income counterparts.

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Tetsuya Hamaguchi

Saitama Medical University

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Narikazu Boku

St. Marianna University School of Medicine

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