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Dive into the research topics where Hiroyasu Ishikura is active.

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Featured researches published by Hiroyasu Ishikura.


Critical Care Medicine | 2008

Natural history of disseminated intravascular coagulation diagnosed based on the newly established diagnostic criteria for critically ill patients: results of a multicenter, prospective survey.

Satoshi Gando; Daizoh Saitoh; Hiroshi Ogura; Toshihiko Mayumi; Kazuhide Koseki; Toshiaki Ikeda; Hiroyasu Ishikura; Toshiaki Iba; Masashi Ueyama; Yutaka Eguchi; Yasuhiro Ohtomo; Kohji Okamoto; Shigeki Kushimoto; Shigeatsu Endo; Shuji Shimazaki

Objective:To survey the natural history of disseminated intravascular coagulation (DIC) in patients diagnosed according to the Japanese Association for Acute Medicine (JAAM) DIC scoring system in a critical care setting. Design:Prospective, multicenter study during a 4-month period. Setting:General critical care center in a tertiary care hospital. Patients:All patients were enrolled when they were diagnosed as DIC by the JAAM DIC scoring system. Interventions:None. Measurements and Main Results:Platelet counts, prothrombin time ratio, fibrinogen, and fibrin/fibrinogen degradation products were measured, and the systemic inflammatory response syndrome criteria met by the patients were determined following admission. Of 3,864 patients, 329 (8.5%) were diagnosed with DIC and the 28-day mortality rate was 21.9%, which was significantly different from that of the non-DIC patients (11.2%) (p < .0001). The progression of systemic inflammation, deterioration of organ function, and stepwise increase in incidence of the International Society on Thrombosis and Haemostasis (ISTH) DIC and its scores all correlated with an increase in the JAAM DIC score as demonstrated by the patients on day 0. There were significant differences in the JAAM DIC score and the variables adopted in the scoring system between survivors and nonsurvivors. The logistic regression analyses showed the JAAM DIC score and prothrombin time ratio on the day of DIC diagnosis to be predictors of patient outcome. The patients who simultaneously met the ISTH DIC criteria demonstrated twice the incidence of multiple organ dysfunction (61.1 vs. 30.5%, p < .0001) and mortality rate (34.4 vs. 17.2%, p = .0015) compared with those without the ISTH DIC diagnosis. Conclusions:This prospective survey demonstrated the natural history of DIC patients diagnosed by the JAAM DIC diagnostic criteria in a critical care setting. The study provides further evidence of a progression from the JAAM DIC to the ISTH overt DIC.


Gut | 2009

Hydrogen sulfide as a novel mediator for pancreatic pain in rodents

Sachiyo Nishimura; Osamu Fukushima; Hiroyasu Ishikura; Tomoko Takahashi; Maho Matsunami; Toshifumi Tsujiuchi; Fumiko Sekiguchi; Mitsuhide Naruse; Yoshihisa Kamanaka; Atsufumi Kawabata

Objective: Hydrogen sulfide (H2S) is formed from l-cysteine by multiple enzymes including cystathionine-γ-lyase (CSE) in mammals, and plays various roles in health and disease. Recently, a pronociceptive role for H2S in the processing of somatic pain was identified. Here, the involvement of H2S in pancreatic pain is examined. Methods: Anaesthetised rats or mice received an injection of NaHS, a donor for H2S, or capsaicin into the pancreatic duct, and the expression of spinal Fos protein was detected by immunohistochemistry. Pancreatitis was created by 6 hourly doses of caerulein in unanaesthetised mice, and pancreatitis-related allodynia/hyperalgesia was evaluated using von Frey hairs. CSE activity and protein levels in pancreatic tissues were measured using the colorimetric method and western blotting, respectively. Results: Either NaHS or capsaicin induced the expression of Fos protein in the superficial layers of the T8 and T9 spinal dorsal horn of rats or mice. The induction of Fos by NaHS but not capsaicin was abolished by mibefradil, a T-type Ca2+ channel blocker. In conscious mice, repeated doses of caerulein produced pancreatitis accompanied by abdominal allodynia/hyperalgesia. Pretreatment with an inhibitor of CSE prevented the allodynia/hyperalgesia, but not the pancreatitis. A single dose of mibefradil reversed the established pancreatitis-related allodynia/hyperalgesia. Either the activity or protein expression of pancreatic CSE increased after the development of caerulein-induced pancreatitis in mice. Conclusions: The data suggest that pancreatic NaHS/H2S most probably targets T-type Ca2+ channels, leading to nociception, and that endogenous H2S produced by CSE and possibly T-type Ca2+ channels are involved in pancreatitis-related pain.


Shock | 2007

SIRS-associated coagulopathy and organ dysfunction in critically ill patients with thrombocytopenia.

Hiroshi Ogura; Satoshi Gando; Toshiaki Iba; Yutaka Eguchi; Yasuhiro Ohtomo; Kohji Okamoto; Kazuhide Koseki; Toshihiko Mayumi; Atsuo Murata; Toshiaki Ikeda; Hiroyasu Ishikura; Masashi Ueyama; Shigeki Kushimoto; Daizoh Saitoh; Shigeatsu Endo; Shuji Shimazaki

Backgrounds: Coagulopathy and thrombocytopenia often occur in critically ill patients, and disseminated intravascular coagulation (DIC) can lead to multiple organ dysfunction and a poor outcome. However, the relation between coagulopathy and systemic inflammatory response has not been thoroughly clarified. Thus, we evaluated coagulative activity, organ dysfunction, and systemic inflammatory response syndrome (SIRS) in critically ill patients with thrombocytopenia and examined the balance between coagulopathy and systemic inflammation. Patients and Methods: Two hundred seventy-three patients, who were admitted to 13 critical care centers in Japan and fulfilled the criteria of platelet count of less than 150•109/L, were included. Coagulative variables (platelet count, fibrin/fibrinogen degradation products, and DIC scores), organ dysfunction index (Sequential Organ Failure Assessment [SOFA] score), and SIRS score in each patient were evaluated for 4 consecutive days after fulfilling the above entry criteria. The effect of SIRS on coagulopathy and organ dysfunction was evaluated in these patients. Results: Both the maximum SIRS score and entry SIRS score had significant relation to the maximum SOFA score during the observation period. Coagulation disorders indicated by the minimum platelet count, maximum DIC scores, and positivity for DIC worsened gradually with increases in SIRS scores. Both the minimum platelet count and maximum DIC scores were significantly correlated with the maximum SOFA score, indicating that a relation exists between coagulopathy and organ dysfunction. Conclusions: In critically ill patients with thrombocytopenia, coagulopathy and organ dysfunction progress with significant mutual correlation, depending on the increase in SIRS scores. The SIRS-associated coagulopathy may play a critical role in inducing organ dysfunction after severe insult.


Thrombosis Research | 2009

Disseminated intravascular coagulation (DIC) diagnosed based on the Japanese Association for Acute Medicine criteria is a dependent continuum to overt DIC in patients with sepsis.

Satoshi Gando; Daizoh Saitoh; Hiroshi Ogura; Toshihiko Mayumi; Kazuhide Koseki; Toshiaki Ikeda; Hiroyasu Ishikura; Toshiaki Iba; Masashi Ueyama; Yutaka Eguchi; Yasuhiro Otomo; Kohji Okamoto; Shigeki Kushimoto; Shigeatsu Endo; Shuji Shimazaki

INTRODUCTION Sepsis is the most common disease associated with disseminated intravascular coagulation (DIC). To test the hypothesis that DIC diagnosed by the Japanese Association for Acute Medicine (JAAM) DIC scoring system (JAAM DIC) constitutes a dependent continuum to overt DIC diagnosed by the International Society on Thrombosis and Haemostasis (ISTH) overt DIC scoring system (ISTH overt DIC) in patients with sepsis, we conducted a retrospective study. MATERIALS AND METHODS The databases from two prospective, multicenter clinical investigations were analyzed. The inclusion criteria comprised patients with sepsis-related DIC, who met the JAAM DIC criteria. RESULTS The present study enrolled 166 patients, of whom 67 met the ISTH overt DIC criteria. All patients with sepsis who developed to overt DIC during the study period could be identified by the JAAM DIC diagnostic criteria in the first study. While the overall 28-day mortality was 31.3%, mortality (40.3%, p=0.0040) and the incidence of multiple organ dysfunction syndrome (70.1%, p=0.008) of the patients with the ISTH overt DIC was approximately one and a half times that of the patients associated with only the JAAM DIC. A stepwise increase in the ISTH overt DIC scores and the incidence of the ISTH overt DIC were also observed in accordance with the increase in the JAAM DIC scores. CONCLUSION DIC diagnosed based on the JAAM DIC diagnostic criteria exists in a dependent continuum to the ISTH overt DIC in patients with sepsis, thus enabling them to receive early treatment.


Critical Care | 2013

Relationship between extravascular lung water and severity categories of acute respiratory distress syndrome by the Berlin definition

Shigeki Kushimoto; T. Endo; Satoshi Yamanouchi; Teruo Sakamoto; Hiroyasu Ishikura; Yasuhide Kitazawa; Yasuhiko Taira; Kazuo Okuchi; Takashi Tagami; Akihiro Watanabe; Junko Yamaguchi; Kazuhide Yoshikawa; Manabu Sugita; Yoichi Kase; Takashi Kanemura; Hiroyuki Takahashi; Yuuichi Kuroki; Hiroo Izumino; Hiroshi Rinka; Ryutarou Seo; Makoto Takatori; Tadashi Kaneko; Toshiaki Nakamura; Takayuki Irahara; Nobuyuki Saito

IntroductionThe Berlin definition divides acute respiratory distress syndrome (ARDS) into three severity categories. The relationship between these categories and pulmonary microvascular permeability as well as extravascular lung water content, which is the hallmark of lung pathophysiology, remains to be elucidated. The aim of this study was to evaluate the relationship between extravascular lung water, pulmonary vascular permeability, and the severity categories as defined by the Berlin definition, and to confirm the associated predictive validity for severity.MethodsThe extravascular lung water index (EVLWi) and pulmonary vascular permeability index (PVPI) were measured using a transpulmonary thermodilution method for three consecutive days in 195 patients with an EVLWi of ≥10 mL/kg and who fulfilled the Berlin definition of ARDS. Collectively, these patients were seen at 23 ICUs. Using the Berlin definition, patients were classified into three categories: mild, moderate, and severe.ResultsCompared to patients with mild ARDS, patients with moderate and severe ARDS had higher acute physiology and chronic health evaluation II and sequential organ failure assessment scores on the day of enrollment. Patients with severe ARDS had higher EVLWi (mild, 16.1; moderate, 17.2; severe, 19.1; P <0.05) and PVPI (2.7; 3.0; 3.2; P <0.05). When categories were defined by the minimum PaO2/FIO2 ratio observed during the study period, the 28-day mortality rate increased with severity categories: moderate, odds ratio: 3.125 relative to mild; and severe, odds ratio: 4.167 relative to mild. On independent evaluation of 495 measurements from 195 patients over three days, negative and moderate correlations were observed between EVLWi and the PaO2/FIO2 ratio (r = -0.355, P<0.001) as well as between PVPI and the PaO2/FIO2 ratio (r = -0.345, P <0.001). ARDS severity was associated with an increase in EVLWi with the categories (mild, 14.7; moderate, 16.2; severe, 20.0; P <0.001) in all data sets. The value of PVPI followed the same pattern (2.6; 2.7; 3.5; P <0.001).ConclusionsSeverity categories of ARDS described by the Berlin definition have good predictive validity and may be associated with increased extravascular lung water and pulmonary vascular permeability.Trial registrationUMIN-CTR ID UMIN000003627


Thrombosis and Haemostasis | 2008

Clinical course and outcome of disseminated intravascular coagulation diagnosed by Japanese Association for Acute Medicine criteria - Comparison between sepsis and trauma

Shigeki Kushimoto; Satoshi Gando; Daizoh Saitoh; Hiroshi Ogura; Toshihiko Mayumi; Kazuhide Koseki; Toshiaki Ikeda; Hiroyasu Ishikura; Toshiaki Iba; Masashi Ueyama; Yutaka Eguchi; Yasuhiro Otomo; Kohji Okamoto; Shigeatsu Endo; Shuji Shimazaki

The Japanese Association for Acute Medicine (JAAM) disseminated intravascular coagulation (DIC) study group recently announced new diagnostic criteria for DIC. These criteria have been prospectively validated and demonstrated to progress to overt DIC as defined by the International Society on Thrombosis and Haemostasis (ISTH). Although an underlying condition is essential for the development of DIC, it has never been clarified if patients with different underlying disorders have a similar course. Among 329 patients with DIC diagnosed by the JAAM criteria, those with underlying sepsis (n = 98) or trauma (n = 95) were compared. The 28-day mortality rate was significantly higher in sepsis patients than trauma patients (34.7% vs. 10.5%, p < 0.0001). Within three days of fulfilling the JAAM criteria, sepsis patients had a lower platelet count, higher prothrombin time ratio, higher systemic inflammatory response syndrome score, and higher Sequential Organ Failure Assessment score compared with trauma patients. On day 3, a significantly higher percentage of trauma patients than sepsis patients showed improvement of DIC (64.2% vs. 30.6%, p < 0.001). These differences were mainly due to patients with lower JAAM DIC scores. More than 50% of the JAAM DIC patients with sepsis who died within 28 days could not be detected by ISTH DIC criteria during the initial three days. In contrast, most trauma patients who died within 28 days had DIC simultaneously diagnosed by JAAM and ISTH criteria, except for those with brain death. These findings suggest that coagulation abnormalities, organ dysfunction, and the outcome of JAAM DIC differ between patients with sepsis and trauma.


Neuropharmacology | 2014

Bladder pain relief by HMGB1 neutralization and soluble thrombomodulin in mice with cyclophosphamide-induced cystitis.

Junichi Tanaka; Kaoru Yamaguchi; Hiroyasu Ishikura; Maho Tsubota; Fumiko Sekiguchi; Yukari Seki; Toshifumi Tsujiuchi; Akira Murai; Takehiro Umemura; Atsufumi Kawabata

High mobility group box 1 (HMGB1), one of damage-associated molecular patterns (DAMPs), plays roles in not only inflammation but also processing of somatic pain. Given that no evidence for roles of HMGB1 in visceral pain signaling is available, we asked if HMGB1 participates in bladder pain accompanying cystitis caused by cyclophosphamide in mice, using the anti-HMGB1 neutralizing antibody and recombinant human soluble thrombomodulin (rhsTM) that sequesters HMGB1 and promotes its degradation by thrombin. Cyclophosphamide, administered i.p., caused bladder pain-like nociceptive behavior and referred hyperalgesia accompanying cystitis symptoms including increased bladder weight, an indicator of edema, in mice. The cyclophosphamide-induced bladder pain and referred hyperalgesia, but not increased bladder weight, were prevented by i.p. preadministration of the anti-HMGB1 neutralizing antibody or rhsTM. HMGB1, given i.p., facilitated the bladder pain and referred hyperalgesia caused by a subeffective dose of cyclophosphamide, an effect blocked by rhsTM. In the cyclophosphamide-treated mice, HMGB1 levels greatly decreased in the bladder tissue, particularly in the urothelial cells, but did not change in the plasma. Low molecular weight heparin, known to inhibit the receptor for advanced glycation end products (RAGE), but not lipopolysaccharide from Rhodobacter sphaeroides, an inhibitor of toll-like receptor 4 (TLR4), blocked the cyclophosphamide-induced bladder pain and referred hyperalgesia. Thus, our data indicate involvement of HMGB1 in the cyclophosphamide-induced bladder pain signaling, but not cystitis itself, and suggest that targeting HMGB1 with rhsTM or blocking RAGE might serve as a novel therapeutic strategy for the management of bladder pain.


Toxicology | 2009

Rhodanese, but not cystathionine-γ-lyase, is associated with dextran sulfate sodium-evoked colitis in mice: A sign of impaired colonic sulfide detoxification?

Eiichi Taniguchi; Maho Matsunami; Takeshi Kimura; Daiki Yonezawa; Tsuyoshi Ishiki; Fumiko Sekiguchi; Hiroyuki Nishikawa; Yuma Maeda; Hiroyasu Ishikura; Atsufumi Kawabata

Clinical studies suggest that colonic luminal hydrogen sulfide (H(2)S), produced by sulfate-reducing bacteria or through other pathways, might be involved in the pathogenesis of inflammatory bowel disease (IBD). Nonetheless, this hypothesis has been poorly investigated by basic studies using laboratory animals. We thus focused on two enzymes, cystathionine-gamma-lyase (CSE) that generates H(2)S from l-cysteine, and rhodanese that directly or indirectly detoxifies H(2)S, particularly in relation to the colitis induced by dextran sulfate sodium (DSS) in mice. CSE was a major H(2)S-forming enzyme in colonic and renal homogenates from mice and rats, and the rhodanese activity was also detectable in both tissues. Colitis-related symptoms including decreased body weight gain, diarrhea, hematochezia and shortening of colon length were observed in the mice drinking DSS. Those symptoms were not or only slightly attenuated by repeated administration of a CSE inhibitor. CSE activity and protein levels in the colonic tissue did not notably change in the mice with colitis. In contrast, the activity and protein/mRNA levels of rhodanese in the colon, but not kidney, significantly decreased nearly in parallel with the development of colitis, followed by elevation of rhodanese activity in red blood cells (RBCs). These data show that rhodanese, but not CSE, is associated with DSS-induced colitis in mice, leading to a hypothesis that impaired detoxification of H(2)S due to down-regulation or suppression of colonic rhodanese is involved in IBD. The delayed enhancement of rhodanese activity in RBCs, a possible compensative event, might be available as a disease marker for IBD.


Journal of Neuroscience Research | 2010

Phosphorylation of ERK in the spinal dorsal horn following pancreatic pronociceptive stimuli with proteinase-activated receptor-2 agonists and hydrogen sulfide in rats: evidence for involvement of distinct mechanisms.

Osamu Fukushima; Sachiyo Nishimura; Maho Matsunami; Yuka Aoki; Hiroyuki Nishikawa; Hiroyasu Ishikura; Atsufumi Kawabata

Noxious stimuli cause prompt phosphorylation of extracellular signal‐regulated kinase (ERK) in the spinal dorsal horn that contributes to facilitation of pain sensation and is often used as an immediate marker for excitation of spinal neurons following somatic and colonic nociception. Here we asked whether two distinct pronociceptive stimuli with proteinase‐activated receptor‐2 (PAR2) agonists and hydrogen sulfide (H2S) in the pancreas cause phosphorylation of ERK in the spinal dorsal horn and also examined involvement of their possible downstream signaling molecules, transient receptor potential vanilloid‐1 (TRPV1) and T‐type Ca2+ channels, respectively. Capsaicin (a TRPV1 agonist), trypsin (an endogenous PAR2 agonist), SLIGRL‐NH2 (a PAR2‐activating peptide), and NaHS (an H2S donor) were infused into the pancreatic duct in anesthetized rats, and phosphorylated ERK in the spinal cord was detected by immunohistochemistry. Intraductal administration of capsaicin and trypsin caused prompt phosphorylation of ERK in the superficial layers of T9, but not T5 or T12, spinal dorsal horn. SLIGRL‐NH2 and NaHS, administered in the same manner, also produced ERK phosphorylation in the corresponding spinal regions. Mibefradil, a T‐type Ca2+ channel blocker, abolished the phosphorylation of ERK caused by intraductal NaHS but not SLIGRL‐NH2. In contrast, capsazepine, an inhibitor of TRPV1, suppressed the phosphorylation of ERK caused by intraductal SLIGRL‐NH2 but not NaHS. Our data thus demonstrate that pancreatic pronociceptive stimuli with PAR2 agonists and H2S cause ERK phosphorylation in the spinal dorsal horn, through activation of TRPV1 and T‐type Ca2+ channels, respectively, and that those two pronociceptive pathways are independent of each other.


Journal of Cardiology | 2012

Effect of intravenous adrenaline before arrival at the hospital in out-of-hospital cardiac arrest

Minoru Machida; Shin-ichiro Miura; Kunihiro Matsuo; Hiroyasu Ishikura; Keijiro Saku

There is some evidence in prospective randomized clinical trials that the administration of adrenaline (AD) before admission for the treatment of out-of-hospital cardiac arrest did not improve survival to hospital discharge. The aim of this study was to evaluate our real-world experience regarding the efficacy of intravenous AD in out-of-hospital cardiac arrest at our university hospital. In this retrospective study, we enrolled and divided 644 patients into AD (AD administration before arrival at the hospital) and non-AD (no AD administration before arrival at the hospital) groups. The patient characteristics including age, sex, percentage of cardiac cause, location of cardiac arrest, and witnessed arrest were similar between the AD and non-AD groups. There were no significant differences between the AD and non-AD groups with regard to return of spontaneous circulation, survival to hospital admission, survival to hospital discharge, or good neurologic recovery at hospital discharge in all patients. In addition, we excluded the data of patients with extrinsic cause. We analyzed whether intravenous AD before arrival in patients with intrinsic cause was effective. The outcomes in the AD group were similar to those in the non-AD group. In conclusion, our study indicated that AD administration before arrival at the hospital for the treatment of out-of-hospital cardiac arrest did not improve the clinical outcome.

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Daizoh Saitoh

National Defense Medical College

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