Toshimitsu Hamasaki

Toshimitsu Hamasaki

orcid

Research Focus & Metrics

Academic Career Length

29Years (1998-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 October 2007 in The Lancet
Verified
Journal Article
Closed access
MKMasafumi Kitakaze
Masafumi Kitakaze
MAMasanori Asakura
Masanori Asakura
JKJiyoong Kim
Jiyoong Kim
YSYasunori Shintani
Yasunori Shintani
HAHiroshi Asanuma
Hiroshi Asanuma
SKSoichiro Kitamura
Soichiro Kitamura

19 July 2013 in Circulation Research
Verified
Journal Article
Closed access
SMSen Matsumoto
Sen Matsumoto
YSYasuhiko Sakata
Yasuhiko Sakata
SSShinichiro Suna
Shinichiro Suna
DNDaisaku Nakatani
Daisaku Nakatani
MUMasaya Usami
Masaya Usami
IKIssei Komuro
Issei Komuro
Rationale:: Despite a recent decline of in-hospital mortality attributable to acute myocardial infarction (AMI), the incidence of ischemic heart failure (HF) in post-AMI patients is increasing. Although various microRNAs have been proposed as diagnostic indicators for AMI, no microRNAs have been established as predictors of ischemic HF that develops after AMI. Objective:: We attempted to identify circulating microRNAs that can serve as reliable predictors of ischemic HF in post-AMI patients. Methods and Results:: Using sera collected a median of 18 days after AMI onset, we screened microRNAs in 21 patients who experienced development of HF within 1 year after AMI and in 65 matched controls without subsequent cardiovascular events after discharge. Among the 377 examined microRNAs, the serum level of only miR-192 was significantly upregulated in AMI patients with development of ischemic HF. Because miR-192 is reported to be p53-responsive, the serum levels of 2 other p53-responsive microRNAs, miR-194 and miR-34a, also were investigated. Interestingly, both microRNAs were coordinately increased with miR-192, particularly in exosomes, suggesting that these microRNAs function as circulating regulators of HF development via the p53 pathway. Furthermore, miR-194 and miR-34a expression levels were significantly correlated with left ventricular end-diastolic dimension 1 year after AMI. Conclusions:: In the sera of post-AMI patients who experienced development of de-novo HF within 1 year of AMI onset, the levels of 3 p53-responsive microRNAs had been elevated by the early convalescent stage of AMI. Further investigations are warranted to confirm the usefulness of these circulating microRNAs for predicting the risk of development of ischemic HF after AMI.

8 October 2010 in Digestive Diseases and Sciences
Verified
Journal Article
Open access
PDF file
KSKentaro Shimizu
Kentaro Shimizu
HOHiroshi Ogura
Hiroshi Ogura
THToshimitsu Hamasaki
Toshimitsu Hamasaki
MGMiki Goto
Miki Goto
OTOsamu Tasaki
Osamu Tasaki
HSHisashi Sugimoto
Hisashi Sugimoto
Background Gut under severe insult is considered to have an important role in promoting infection and multiple organ dysfunction syndrome from the viewpoint of altered intestinal epithelium, immune system and commensal bacteria. There are few reports, however, about the relationship between gut flora and septic complications. Methods We analyzed gut flora in patients with systemic inflammatory response syndrome (SIRS) and evaluated key bacteria and their cutoff values for infectious complications and mortality by using classification and regression trees (CART). Eighty-one SIRS patients with a serum C-reactive protein level higher than 10 mg/dL treated in the intensive care unit (ICU) for more than 2 days were included for the study. We quantitatively evaluated nine types of bacteria in fecal samples by plate or tube technique. Two hundred seventy-one samples were analyzed using CART and logistic regression. Results The dominant factors for complication of enteritis were the minimum number of total obligate anaerobes and the maximum number of Staphylococcus and Enterococcus. The dominant factors for complication of bacteremia were the minimum numbers of total obligate anaerobes and total facultative anaerobes. The dominant factors for mortality were the numbers of total obligate anaerobes and total facultative anaerobes and age. Conclusions A decrease in total obligate anaerobes and an increase in pathogenic bacteria in the gut are associated with septic complications and mortality in patients with SIRS. The altered gut flora may be a potential prognostic marker in SIRS patients.

2 December 2004 in European Journal of Neuroscience
Verified
Journal Article
Closed access
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FSFuminobu Sugai
Fuminobu Sugai
YYYoichi Yamamoto
Yoichi Yamamoto
KMKatsuyuki Miyaguchi
Katsuyuki Miyaguchi
ZZZhiwei Zhou
Zhiwei Zhou
HSHisae Sumi
Hisae Sumi
SSSaburo Sakoda
Saburo Sakoda

1 July 2010 in Investigative Ophthalmology & Visual Science
Verified
Journal Article
Closed access
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YIYasushi Ikuno
Yasushi Ikuno
YJYukari Jo
Yukari Jo
THToshimitsu Hamasaki
Toshimitsu Hamasaki
YTYasuo Tano
Yasuo Tano
Purpose. To identify the risk factors for development of myopic choroidal neovascularization (mCNV), a major cause of visual impairment. Methods. Enrolled in the study were 23 consecutive patients with bilateral high myopia (axial length, ≥26.5 mm or refractive error, ≤8 D) and unilateral newly developed mCNV who presented to the Myopia Clinic, Osaka University Hospital. Spectral-domain optical coherence tomography (SD-OCT) showed that the fellow eyes had a normal macula. The parameters in the affected and fellow eyes were compared between the individual patients, including best-corrected visual acuity (BCVA), intraocular pressure (IOP), refractive error, axial length, choroidal thickness (CT) (subfoveal, 1.5 mm superiorly and inferiorly), posterior staphyloma height 3 mm from the fovea, length of retinal pigment epithelium (RPE) curvature within 6 mm measured on SD-OCT images, and choroidal degeneration and lacquer crack formation, graded according to a published method. Results. The IOP, axial length, refractive error, and chorioretinal degeneration did not differ significantly. Affected eyes had a significantly higher lacquer crack grade (P < 0.05). The superior CT was not significantly different; the subfoveal and inferior CTs were significantly lower in the affected eyes (P < 0.05 and P < 0.001, respectively). The absolute value of the nasal posterior staphyloma height from the fovea was significantly greater in the affected eyes (P < 0.05), and the affected eyes had a significantly (P < 0.05) longer RPE curvature. Conclusions. Choroidal thinning resulting from increased RPE/choroid curvature is a risk factor for unilateral mCNV.

1 February 2013 in Circulation: Cardiovascular Interventions
Verified
Journal Article
Closed access
OIOsamu Iida
Osamu Iida
MNMasato Nakamura
Masato Nakamura
YYYasutaka Yamauchi
Yasutaka Yamauchi
DKDaizo Kawasaki
Daizo Kawasaki
YYYoshiaki Yokoi
Yoshiaki Yokoi
SNShinsuke Nanto
Shinsuke Nanto
Background—: Recent technical advances have made endovascular treatment (EVT) an alternative first-line treatment for critical limb ischemia. Methods and Results—: A prospective multicenter study was conducted to evaluate the clinical outcomes of 314 Japanese critical limb ischemia patients (mean age, 73±10 years) with infrainguinal arterial lesions who underwent EVT. Patients were enrolled from December 2009 to July 2011 and were followed-up for 12 months. The primary end point was amputation-free survival (AFS) at 12 months. Secondary end points were anatomic, clinical, and hemodynamic measures, including 12-month freedom from major adverse limb events. The 12-month AFS rate was 74%, with body mass index <18.5 (hazard ratio [HR], 2.22; P =0.008), heart failure (HR, 1.73; P =0.04), and wound infection (HR, 1.89; P =0.03) associated with a poor prognosis for AFS. The 12-month major adverse limb event-free rate was 88%, with hemodialysis (HR, 1.98; P =0.005), heart failure (HR, 1.69; P =0.02), and Rutherford classification 6 (HR, 2.25; P =0.002) associated with a poor prognosis for major adverse limb events. The median time for wound healing was 97 days, with body mass index <18.5 (HR, 0.54; P =0.03) and wound infection (HR, 0.60; P =0.04) being significant risk factors for unhealed wounds after EVT. At 12 months, 34% had undergone reintervention (bypass surgery, 2.6%; repeat EVT, 31.7%), and 73% were major adverse event–free. Conclusions—: The high reintervention rate notwithstanding, EVT was an effective treatment for Japanese critical limb ischemia patients with infrainguinal disease, with satisfactory AFS and major adverse limb event-free rates. The results of this study will be helpful for the future evaluation of critical limb ischemia therapy. Clinical Trial Registration—: URL: http://www.umin.ac.jp/ctr . Unique identifier: UMIN000002830.