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Dive into the research topics where Masayuki Hashiguchi is active.

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Featured researches published by Masayuki Hashiguchi.


PLOS ONE | 2015

Meta-Analysis: Effects of Probiotic Supplementation on Lipid Profiles in Normal to Mildly Hypercholesterolemic Individuals

Mikiko Shimizu; Masayuki Hashiguchi; Tsuyoshi Shiga; Hiroomi Tamura; Mayumi Mochizuki

Introduction Recent experimental and clinical studies have suggested that probiotic supplementation has beneficial effects on serum lipid profiles. However, there are conflicting results on the efficacy of probiotic preparations in reducing serum cholesterol. Objective To evaluate the effects of probiotics on human serum lipid levels, we conducted a meta-analysis of interventional studies. Methods Eligible reports were obtained by searches of electronic databases. We included randomized, controlled clinical trials comparing probiotic supplementation with placebo or no treatment (control). Statistical analysis was performed with Review Manager 5.3.3. Subanalyses were also performed. Results Eleven of 33 randomized clinical trials retrieved were eligible for inclusion in the meta-analysis. No participant had received any cholesterol-lowering agent. Probiotic interventions (including fermented milk products and probiotics) produced changes in total cholesterol (TC) (mean difference –0.17 mmol/L, 95% CI: –0.27 to –0.07 mmol/L) and low-density lipoprotein cholesterol (LDL-C) (mean difference –0.22 mmol/L, 95% CI: –0.30 to –0.13 mmol/L). High-density lipoprotein cholesterol and triglyceride levels did not differ significantly between probiotic and control groups. In subanalysis, long-term (>4-week) probiotic intervention was statistically more effective in decreasing TC and LDL-C than short-term (≤4-week) intervention. The decreases in TC and LDL-C levels with probiotic intervention were greater in mildly hypercholesterolemic than in normocholesterolemic individuals. Both fermented milk product and probiotic preparations decreased TC and LDL-C levels. Gaio and the Lactobacillus acidophilus strain reduced TC and LDL-C levels to a greater extent than other bacterial strains. Conclusions In conclusion, this meta-analysis showed that probiotic supplementation could be useful in the primary prevention of hypercholesterolemia and may lead to reductions in risk factors for cardiovascular disease.


Thrombosis Research | 2012

Clinical outcome in Japanese elderly patients with non-valvular atrial fibrillation taking warfarin: A single-center observational study

Miyoko Naganuma; Tsuyoshi Shiga; Kumi Sato; Kagari Murasaki; Masayuki Hashiguchi; Mayumi Mochizuki; Nobuhisa Hagiwara

BACKGROUND Although a lower target prothrombin time-international normalized ratio (PT-INR) with warfarin therapy is recommended in Japan for atrial fibrillation (AF) patients ≥70 years of age, few studies have provided supporting data. The current study aimed to evaluate the clinical outcome in elderly Japanese patients with non-valvular AF who were taking warfarin. METHODS We conducted a cohort study of 845 consecutive non-valvular AF patients ≥70 years of age who were taking warfarin (median age, 74 years; 30.5% women) with a median follow-up period of 27 months (4-69 months). Of these patients, 29.7% had a history of stoke/transient ischemic attack (TIA), and 73.1% of the patients had a CHADS(2) score ≥2. The occurrence of thromboembolic events, including ischemic stroke, TIA and other systemic embolisms, and major bleeding events were validated through a review of medical records. RESULTS The incidence of thromboembolic and major bleeding events were 3.8 and 2.1% per year, respectively. A higher incidence of both events was observed in patients with a CHADS(2) score ≥3. The multivariate analysis showed that prior stroke/TIA (odds ratio 1.7, 95% CI 1.0-2.7) and diabetes (odds ratio 1.7, 95% CI 1.0-2.8) were independent risks of thromoembolic events. A HAS-BLED score ≥3 represented a risk for major bleeding (hazard ratio 2.8, 95% CI 1.7-4.6). A PT-INR of 1.5-2.5 indicated a low incidence of thromboembolic and major bleeding events in patients with a CHADS(2) score ≥2. CONCLUSIONS Our results demonstrate that a target PT-INR of 2.0 and a range of 1.5-2.5 may be safe for elderly Japanese patients with non-valvular AF.


Journal of Pharmaceutical Health Care and Sciences | 2015

Meta-analysis of the efficacy and safety of Ginkgo biloba extract for the treatment of dementia

Masayuki Hashiguchi; Yuriko Ohta; Mikiko Shimizu; Junya Maruyama; Mayumi Mochizuki

BackgroundThe benefit of Ginkgo biloba for the treatment of dementia remains controversial. The aim of this study was to evaluate the efficacy and safety of Ginkgo biloba in patients with dementia in whom administration effects were reported using meta-analysis.MethodsWe searched MEDLINE, Embase, the Cochrane databases, and Ichushi for controlled trials of Ginkgo biloba for the treatment dementia. Clinical characteristics and outcomes were extracted. Meta-analysis results were expressed as standard mean differences (SMDs) in scores of the Syndrome Kurztest (SKT), Alzheimer’s Disease Assessment Scale Cognitive Subscale (ADAS-Cog) for cognition efficacy, or odds ratios (ORs) for dropouts and adverse drug reactions.ResultsThirteen studies using the extract EGb761 met our inclusion criteria, which were duration of 12 to 52 weeks and daily dose of more than 120 mg, and included a total of 2381 patients. Meta-analysis was performed by using 9 of 13 studies, 7 of which used the SKT and 2 ADAS-Cog (dose 120 mg, 26 weeks) scores as efficacy parameters. In meta-analysis of all patients, SMDs (95% confidence interval [CI]) in the change in SKT scores (7 studies) were in favor of Ginkgo biloba over placebo (SMD = –0.90 [–1.46, –0.34]), but 2 studies that used ADAS-Cog did not show a statistically significant difference from placebo for ADAS-Cog (–0.06 [–0.41, 0.30]). For Alzheimer’s disease (AD) and vascular dementia (VaD) subgroups, SMDs [95% CI] in SKT in the combined AD and VaD subgroup (–1.07 [–1.66, –0.47]) and AD subgroup (–1.36 [–2.27, –0.46]) were in favor of Ginkgo biloba over placebo. In terms of daily dose of Ginkgo biloba in the combined AD and VaD subgroup, SMD in SKT score in 240-mg daily dose groups was significantly greater than with placebo (–0.71 [–1.28, –0.14]). Dropout rates for any reason did not differ between two groups, but dropout rates due to side effects were significantly lower in Ginkgo biloba groups compared with placebo groups (OR = 1.72 [1.06, 2.80]).ConclusionsTaking a 240-mg daily dose of Ginkgo biloba extract is effective and safe in the treatment of dementia.


Journal of Chromatography B: Biomedical Sciences and Applications | 1998

Quantitative determination of disopyramide, verapamil and flecainide enantiomers in rat plasma and tissues by high-performance liquid chromatography

Kazuhiko Hanada; Satoko Akimoto; Keiko Mitsui; Masayuki Hashiguchi; Hiroyasu Ogata

Enantiomers of disopyramide (DP), flecainide (FLC) and verapamil (VP) were extracted from rat plasma and tissues (brain, lung, heart, liver, kidney and muscle), followed by quantitative determination using enantioselective high-performance liquid chromatography with chiral stationary-phase columns. The recoveries of S-(+)- and R-(-)-DP from tissues were higher than 69%, and the within- and between-day coefficients of variation were very low (0.5 - 5.7%). The lower limits of detection in each tissue were less than 289 ng/g tissue. The recoveries of S-(+)- and R-(-)-FLC from tissues were higher than 88%, and the within- and between-day coefficients of variation were 1.2-6.0%. The lower limits of detection in each tissue were less than 37 ng/g tissue. The recoveries of S-(-)- and R-(+)-VP from tissues were higher than 80%, and the within- and between-day coefficients of variation were 0.5-6.2%. The lower limits of detection in each tissue were less than 51 ng/g tissue. The analytical methods established in this study will be suitable for determining the concentrations of the enantiomers of these anti-arrhythmic agents in rat plasma and tissues.


Drug Design Development and Therapy | 2015

Effect of database profile variation on drug safety assessment: an analysis of spontaneous adverse event reports of Japanese cases

Kaori Nomura; Kunihiko Takahashi; Yasushi Hinomura; Genta Kawaguchi; Yasuyuki Matsushita; Hiroko Marui; Tatsuhiko Anzai; Masayuki Hashiguchi; Mayumi Mochizuki

Background The use of a statistical approach to analyze cumulative adverse event (AE) reports has been encouraged by regulatory authorities. However, data variations affect statistical analyses (eg, signal detection). Further, differences in regulations, social issues, and health care systems can cause variations in AE data. The present study examined similarities and differences between two publicly available databases, ie, the Japanese Adverse Drug Event Report (JADER) database and the US Food and Drug Administration Adverse Event Reporting System (FAERS), and how they affect signal detection. Methods Two AE data sources from 2010 were examined, ie, JADER cases (JP) and Japanese cases extracted from the FAERS (FAERS-JP). Three methods for signals of disproportionate reporting, ie, the reporting odds ratio, Bayesian confidence propagation neural network, and Gamma Poisson Shrinker (GPS), were used on drug-event combinations for three substances frequently recorded in both systems. Results The two databases showed similar elements of AE reports, but no option was provided for a shareable case identifier. The average number of AEs per case was 1.6±1.3 (maximum 37) in the JP and 3.3±3.5 (maximum 62) in the FAERS-JP. Between 5% and 57% of all AEs were signaled by three quantitative methods for etanercept, infliximab, and paroxetine. Signals identified by GPS for the JP and FAERS-JP, as referenced by Japanese labeling, showed higher positive sensitivity than was expected. Conclusion The FAERS-JP was different from the JADER. Signals derived from both datasets identified different results, but shared certain signals. Discrepancies in type of AEs, drugs reported, and average number of AEs per case were potential contributing factors. This study will help those concerned with pharmacovigilance better understand the use and pitfalls of using spontaneous AE data.


The Journal of Clinical Pharmacology | 1996

No Effect of High-Protein Food on the Stereoselective Bioavailability and Pharmacokinetics of Verapamil

Masayuki Hashiguchi; Hiroyasu Ogata; Akira Maeda; Yuka Hirashima; Shizuka Ishii; Yuko Mori; Toshiaki Amamoto; Toshiya Handa; Norio Otsuka; Shin Irie; Akinori Urae; Ryuji Urae; Ryoji Kimura

The effects of high‐protein food on the bioavailability of both the racemate and individual enantiomers of verapamil were investigated in 12 healthy volunteers using a randomized crossover design. Food had no effect on any parameter of bioavailability for both the racemate and the individual enantiomers of verapamil except time to maximum concentration (tmax), which was significantly prolonged after food intake. The pharmacokinetics of the enantiomers of norverapamil were not significantly changed by food intake. These results suggest that high‐protein food does not alter the pharmacokinetics and bioavailability of either the racemate or the individual enantiomers of verapamil. Therefore, the clinical efficacy of verapamil is not related to food intake, except for a slight prolongation in the time to onset of the pharmacologic effects. The present data can be applied to the high‐protein content meal intake.


Patient Preference and Adherence | 2015

Patients views and experiences in online reporting adverse drug reactions: Findings of a national pilot study in Japan

Michiko Yamamoto; Kiyoshi Kubota; Mitsuhiro Okazaki; Akira Dobashi; Masayuki Hashiguchi; Hirohisa Doi; Machi Suka; Mayumi Mochizuki

Background Patients have been allowed to report adverse drug reactions (ADRs) directly to the government in some countries, which would contribute to pharmacovigilance. Objective We started a pilot study to determine whether web-based patient ADR reporting would work in Japan. This article aims to describe the characteristics of the patient reporters, and to clarify patient views and experiences of reporting. Methods Patients who submitted online ADR reports were contacted to respond to an ADR reporting questionnaire; only consenting reporters were included. Subjects with multiple responses were excluded from analysis. The questionnaire consisted of both closed and open questions. Questionnaire responses were examined using Pearson’s chi-squared test. Results A total of 220 web-based ADR reports were collected from January to December 2011; questionnaires were sent to 190 reporters, excluding those who gave multiple reports and those that refused to be contacted. Responses were obtained from 94 individuals (effective response rate: 49.5%). The median respondent age was 46.0 years. Sixty-three respondents found out about this pilot study on the Internet (67.0%). The numbers of respondents claiming that they had difficulty recalling the time/date of ADR occurrence were 16 patient reporters and three non-patient reporters. The number of reporters who found it difficult to complete the online reporting form was 22 patients (26.2%) and one non-patient (10%). Fifty-seven respondents (60.6%) expected feedback after reporting and many respondents wanted to know the process of ADR data collection and related information. Seventy-three respondents (77.7%) stated that they would report ADRs again in future. Conclusion Throughout the entire questionnaire, online patient ADR reporting was received with a forward-looking, positive approach. To facilitate smoother web-based reporting experiences in future, some improvements may be required in online ADR reporting forms, particularly with regard to respondent feedback.


The Journal of Clinical Pharmacology | 1992

Diurnal effect on caffeine clearance.

Masayuki Hashiguchi; Akio Fujimura; Kyoichi Ohashi; Akio Ebihara

Caffeine (300 mg) was given orally to nine healthy subjects at 10:00 am (day trial) or at 10:00 pm (night trial) using a crossover design. Saliva was obtained at 0.5, 1, 1.5, 2, 3, 4, 6, and 8 hours after administration of caffeine. Urine was collected for 8 hours after caffeine dosing. Caffeine clearances in saliva during the day tried were not different from those in the night trial. No significant difference was observed in urinary molar ratios of metabolites (AFMU+ 1X + 1U / 17U) between the two trials. These data suggest that caffeine clearances in saliva do not vary with its administration time. Since caffeine clearances in plasma are reflected in the urinary ratios of caffeine metabolites, its clearance in plasma might also not be altered by the time of dosing.


Clinical Pharmacology & Therapeutics | 1992

Acetylation polymorphism of caffeine in a Japanese population

Masayuki Hashiguchi; Akio Ebihara

The frequency distribution of N‐acetylation of caffeine was determined in 140 unrelated healthy Japanese subjects by measuring the amount of two main metabolites of caffeine, 5‐acetylamino‐6‐formylamino‐3‐methyluracil (AFMU) and 1‐methylxanthine (1X), in urine after an oral dose of caffeine. N‐Acetylation capacity for caffeine appeared to be polymorphic: 15 subjects (10.7%) were phenotyped as slow acetylators, whereas 125 subjects (89.3%) were phenotyped as rapid ones. The urinary molar excretion ratio of AFMU (AFMU/1X) in 2 hours‐urine samples ranged from 0.03 (slow acetylators) to 2.66 (rapid acetylators). The frequency of slow acetylators in this study was similar to that reported previously for the isoniazid and dapsone polymorphism in Japanese populations.


British Journal of Clinical Pharmacology | 2014

Indirect comparison analysis of efficacy and safety between olanzapine and aripiprazole for schizophrenia

Taro Kunitomi; Masayuki Hashiguchi; Mayumi Mochizuki

AIMS Indirect comparison (IC) and direct comparison (DC) between aripiprazole and olanzapine for schizophrenia were conducted to compare their efficacy and safety. The objective was to determine the usability of IC and consistency of results delivered by the two comparisons. Factors that might influence the inconsistency of results were also investigated. METHODS ICs and DCs were conducted using the change from baseline of the Positive and Negative Syndrome Scale (PANSS) total score as an efficacy endpoint and the dropout rate was selected as a safety endpoint. Placebo and risperidone were used as common comparators for ICs. RESULTS A literature search identified 20 articles. The efficacy analysis gave results on the mean difference in PANSS change (95% CI) of -5.72 (-10.22, -1.22) in ICs using placebo as a common comparator and -7.41 (-15.96, 1.14) in DCs. When using risperidone as a common comparator, it was -9.15 (-20.12, 1.82). In rate ratio analysis of the all cause dropout rate, the IC result was 1.17 (0.83, 1.65) using placebo as a common comparator and 1.56 (0.57, 4.26) using risperidone as a common comparator. Both analyses gave consistent results between ICs and DCs. A slightly lower estimated value was observed in ICs using placebo. CONCLUSIONS This study demonstrated that ICs between olanzapine and aripiprazole can deliver results consistent with those of DCs. It is also suggested that the selection of a common comparator is important when control group bias is suspected in the data set.

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Tsuyoshi Shiga

Meiji Pharmaceutical University

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