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Dive into the research topics where Akiyo Kawada is active.

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Featured researches published by Akiyo Kawada.


Neurogastroenterology and Motility | 2015

Variant parameter values—as defined by the Chicago Criteria—produced by ManoScan and a new system with Unisensor catheter

Shikou Kuribayashi; Katsuhiko Iwakiri; Akiyo Kawada; Noriyuki Kawami; Shintaro Hoshino; Nana Takenouchi; Hiroko Hosaka; Yasuyuki Shimoyama; Osamu Kawamura; Masanobu Yamada; Motoyasu Kusano

Recently reported normal values for esophageal motility obtained by high‐resolution manometry (HRM) using a system with a Unisensor catheter were significantly different from those obtained by the ManoScan®, which could result in a wrong diagnosis. To clarify whether these differences were due to system or subject differences, we compared the manometric parameter values between ManoScan and a new system with a Unisensor catheter (Starlet) in the same subjects.


Alimentary Pharmacology & Therapeutics | 2012

Monosodium glutamate stimulates secretion of glucagon‐like peptide‐1 and reduces postprandial glucose after a lipid‐containing meal

Hiroko Hosaka; Motoyasu Kusano; Hiroaki Zai; Akiyo Kawada; Shikou Kuribayashi; Yasuyuki Shimoyama; Atsuto Nagoshi; Masaki Maeda; Osamu Kawamura; Masatomo Mori

Monosodium l‐glutamate (MSG) is known to influence the endocrine system and gastrointestinal (GI) motility. The mechanism of postprandial glycemic control by food in the GI tract is mostly unknown and of great interest.


Journal of Gastroenterology and Hepatology | 2012

Development and evaluation of a modified Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease to distinguish functional dyspepsia from non-erosive reflux disease.

Motoyasu Kusano; Hiroko Hosaka; Akiyo Kawada; Shikou Kuribayashi; Yasuyuki Shimoyama; Osamu Kawamura; Fumitaka Moki

Background and Aim:  The Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease (FSSG) is the standard questionnaire used in Japan for the diagnosis of gastroesophageal reflux disease (GERD) and assessment of the response to treatment. We modified the FSSG in order to assess dyspepsia symptoms, and evaluated the modified questionnaire.


Digestion | 2015

Evaluation of Proton Pump Inhibitor-Resistant Nonerosive Reflux Disease by Esophageal Manometry and 24-Hour Esophageal Impedance and pH Monitoring

Osamu Kawamura; Hiroko Hosaka; Yasuyuki Shimoyama; Akiyo Kawada; Shiko Kuribayashi; Motoyasu Kusano; Masanobu Yamada

Background: Patients with proton pump inhibitor (PPI)-resistant nonerosive reflux disease (NERD) include subgroups that have markedly different pathophysiology. This study aimed to clarify the pathophysiology of NERD by esophageal manometry with 24-hour esophageal impedance and pH monitoring. Methods: Eighteen consecutive outpatients referred to our expert center for functional gastrointestinal motility with suspected PPI-resistant NERD were enrolled. Manometry was performed to detect esophageal motility disorders. Subsequently, 24-hour esophageal impedance and pH monitoring was done while patients were on PPI therapy. Results: Manometry revealed 1 case of achalasia, 1 case of nutcracker esophagus and 3 cases of diffuse esophageal spasm. Three patients had ineffective esophageal motility, with impedance and pH monitoring being performed in 2 of them. Esophageal acid exposure (%time pH <4) was normal in both, but the symptom index (SI) was positive for nonacidic reflux in 1 patient. One of the 10 patients with normal esophageal motility had abnormal esophageal acid exposure. The SI was positive for weakly acidic and nonacidic reflux in 3 of the remaining 9 patients with normal esophageal acid exposure. Five of the other 6 patients seemed to have functional heartburn. Conclusion: A substantial percentage (28%) of patients with suspected PPI-resistant NERD had primary esophageal motility disorders. Both nonacidic reflux and weakly acidic reflux are important contributors to the symptoms of patients with PPI-resistant NERD. Esophageal manometry is required to exclude motility disorders, while 24-hour esophageal impedance and pH monitoring is invaluable for assessing symptom-reflux associations and the indications for fundoplication in patients with suspected PPI-resistant NERD.


Current Pharmaceutical Design | 2014

Gastrointestinal Motility and Functional Gastrointestinal Diseases

Motoyasu Kusano; Hiroko Hosaka; Akiyo Kawada; Shiko Kuribayashi; Yasuyuki Shimoyama; Hiroaki Zai; Osamu Kawamura; Masanobu Yamada

Digestive tract motility patterns are closely related to the pathophysiology of functional gastrointestinal diseases (FGID), and these patterns differ markedly between the interdigestive period and the postprandial period. The characteristic motility pattern in the interdigestive period is so-called interdigestive migrating contraction (IMC). IMCs have a housekeeping role in the intestinal tract, and could also be related to FGID. IMCs arising from the stomach are called gastrointestinal IMCs (GI-IMC), while IMCs arising from the duodenum without associated gastric contractions are called intestinal IMCs (I-IMC). It is thought that I-IMCs are abnormal in FGID. Transport of food residue to the duodenum via gastric emptying is one of the most important postprandial functions of the stomach. In patients with functional dyspepsia (FD), abnormal gastric emptying is a possible mechanism of gastric dysfunction. Accordingly, delayed gastric emptying has attracted attention, with prokinetic agents and herbal medicines often being administered in Japan to accelerate gastric emptying in patients who have anorexia associated with dyspepsia. Recently, we found that addition of monosodium L-glutamate (MSG) to a high-calorie liquid diet rich in casein promoted gastric emptying in healthy men. Therefore, another potential method of improving delayed gastric emptying could be activation of chemosensors that stimulate the autonomic nervous system of the gastrointestinal tract, suggesting a role for MSG in the management of delayed gastric emptying in patients with FD.


Journal of Neurogastroenterology and Motility | 2016

Liquid-containing Refluxes and Acid Refluxes May Be Less Frequent in the Japanese Population Than in Other Populations: Normal Values of 24-hour Esophageal Impedance and pH Monitoring

Osamu Kawamura; Yukie Kohata; Noriyuki Kawami; Hiroshi Iida; Akiyo Kawada; Hiroko Hosaka; Yasuyuki Shimoyama; Shiko Kuribayashi; Yasuhiro Fujiwara; Katsuhiko Iwakiri; Masahiko Inamori; Motoyasu Kusano; Micho Hongo

Background/Aims Twenty-four-hour esophageal impedance and pH monitoring allows detection of all types of reflux episodes and is considered the best technique for identifying gastroesophageal refluxes. However, normative data for the Japanese population are lacking. This multicenter study aimed to establish the normal range of 24-hour esophageal impedance and pH data both in the distal and the proximal esophagus in Japanese subjects. Methods Forty-two healthy volunteers (25 men and 17 women) with a mean ± standard deviation age of 33.3 ± 12.4 years (range: 22–72 years) underwent a combined 24-hour esophageal impedance and pH monitoring. According to the physical and pH properties, distal or proximal esophageal reflux events were categorized. Results Median 45 reflux events occurred in 24 hours, and the 95th percentile was 85 events. Unlike previous reports, liquid-containing reflux events are median 25/24 hours with the 95th percentile of 62/24 hours. Acidic reflux events were median 11/24 hours with the 95th percentile of 39/24 hours. Non-acidic gas reflux events were median 15/24 hours with the 95th percentile of 39/24 hours. Proximal reflux events accounted for 80% of the total reflux events and were mainly non-acidic gas refluxes. About 19% of liquid and mixed refluxes reached the proximal esophagus. Conclusions Unlike previous studies, liquid-containing and acidic reflux events may be less frequent in the Japanese population. Non-acidic gas reflux events may be frequent and a cause of frequent proximal reflux events. This study provides important normative data for 24-hour impedance and pH monitoring in both the distal and the proximal esophagus in the Japanese population.


Journal of Clinical Biochemistry and Nutrition | 2017

Increase of transient lower esophageal sphincter relaxation associated with cascade stomach

Akiyo Kawada; Motoyasu Kusano; Hiroko Hosaka; Shiko Kuribayashi; Yasuyuki Shimoyama; Osamu Kawamura; Junichi Akiyama; Masanobu Yamada; Masako Akuzawa

We previously reported that cascade stomach was associated with reflux symptoms and esophagitis. Delayed gastric emptying has been believed to initiate transient lower esophageal sphincter relaxation (TLESR). We hypothesized that cascade stomach may be associated with frequent TLESR with delayed gastric emptying. Eleven subjects with cascade stomach and 11 subjects without cascade stomach were enrolled. Postprandial gastroesophageal manometry and gastric emptying using a continuous 13C breath system were measured simultaneously after a liquid test meal. TLESR events were counted in early period (0–60 min), late period (60–120 min), and total monitoring period. Three parameters of gastric emptying were calculated: the half emptying time, lag time, and gastric emptying coefficient. The median frequency of TLESR events in the cascade stomach and non-cascade stomach groups was 6.0 (median), 4.6 (interquartile range) vs 5.0, 3.0 in the early period, 5.0, 3.2 vs 3.0, 1.8 in the late period, and 10.0, 6.2 vs 8.0, 5.0 in the total monitoring period. TLESR events were significantly more frequent in the cascade stomach group during the late and total monitoring periods. In contrast, gastric emptying parameters showed no significant differences between the two groups. We concluded that TLESR events were significantly more frequent in persons with cascade stomach without delayed gastric emptying.


Gastroenterology | 2015

Tu1413 Relationship Between Esophageal Pressure Changes in Different Body Positions and Bolus Dynamics at the Esophago-Gastric Junction

Shiko Kuribayashi; Hiroko Hosaka; Akiyo Kawada; Junichi Akiyama; Yasuyuki Shimoyama; Osamu Kawamura; Masanobu Yamada; Motoyasu Kusano

Background: The Chicago classification is useful to classify esophageal motility disorders; however, the clinical importance of some diagnoses such as esophago-gastric junction (EGJ) outflow obstruction should be clarified. There are several cases in which it is difficult to determine if a high integral relaxation pressure (IRP) value in the supine position (supine IRP) has causes dysphagia because IRP in the sitting position (sitting IRP) is lower. Although the relationship between EGJ pressure and bolus dynamics at the EGJ has been assessed, the relationship between esophageal pressure and bolus dynamics at the EGJ is not fully understood.Aim: To clarify the relationship between esophageal pressure changes in different body positions and bolus dynamics at the EGJ. Material and Methods: High resolution manometry (HRM) was performed using ManoScan® in 43 patients with esophageal symptoms such as dysphagia, chest pain or heartburn. Ten 5-ml water swallows were performed in the supine position to evaluate esophageal motility, followed by at least five 5-ml water swallows were repeated in the sitting position. Moreover, an esophagogram in the upright position was performed in all patients. Pressure values were calculated by ManoView® and esophageal motility disorders were diagnosed by the Chicago classification criteria. Barium bolus dynamics were classified into 4 types: i) bolus passed smoothly at the EGJ (type 1), ii) bolus was pooled in the esophagus and then cleared by peristalsis (type 2), iii) bolus passed at the EGJ with minor pooling in the esophagus (type 3), and iv) most of bolus was pooled in the esophagus (type 4). The Mann-Whitney test or the Kruskal-Wallis test was used to compare pressure values.Results: The patient diagnoses, IRP, and intrabolus pressure (IBP) values in different body positions, and the bolus dynamics at the EGJ are shown in the Table. Although the IRP was similar in different body positions in patients with achalasia, the sitting IRP was significantly lower than the supine IRP in patients with other abnormalities or normal peristalsis. Bolus dynamics varied according to esophageal motility abnormalities. The bolus was pooled in the esophagus (type 3 or 4) in all patients with achalasia and absent peristalsis, and in some patients with weak or frequent failed peristalsis. The type 2 bolus dynamics were observed in all, but one patients with EGJ outflow obstruction. The sitting IRP in patients with type 2 or 4 bolus dynamics was significantly higher than that in patients with type 1 or 3 bolus dynamics (median 9.4 vs. 4.4 mmHg, respectively, p<0.01). Conclusions: Both EGJ relaxation and esophageal peristalsis are important for esophageal


Photodiagnosis and Photodynamic Therapy | 2014

Photodynamic therapy for local recurrence of esophageal cancer in the esophagus after resection and free jejunal loop interposition for pharyngeal cancer

Yasuyuki Shimoyama; Motoyasu Kusano; Shiko Kuribayashi; Akiyo Kawada; Hiroko Hosaka; Osamu Kawamura; Taku Tomizawa; Toshihiko Sagawa; Hidetoshi Yasuoka; Masafumi Mizuide; Masanobu Yamada

a Department of Gastroenterology, Gunma University Hospital, Address: 3-39-15 Showamachi, Maebashi, Gunma 371-8511, Japan b Department of Endoscopy and Endoscopic Surgery, Gunma University Hospital, Address: 3-39-15 Showamachi, Maebashi, Gunma 371-8511, Japan c Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Address: 3-39-22 Showamachi, Maebashi, Gunma 371-8511, Japan Available online 2 June 2014


Gastroenterology | 2014

Tu1994 Increased Frequency of Transient Lower Esophageal Sphincter (LES) Relaxation in Cascade Stomach

Akiyo Kawada; Hiroko Hosaka; Shiko Kuribayashi; Shingo Ishihara; Yasuyuki Shimoyama; Osamu Kawamura; Motoyasu Kusano; Masanobu Yamada

Background: In the Chicago Classification (CC) peristaltic integrity is determined by the size of the largest break in the isobaric contour. However, bolus clearance might be affected by the occurrence of non-continuous breaks. The aim of the study was to assess the effect of peristaltic integrity on bolus clearance by using pressure-flow analysis. Methods: 22 solidstate high-resolution impedance manometry (HRIM) tracings of 10 liquid swallows of healthy asymptomatic adults (6M; mean age 36.1 SD 11.7 years) were retrospectively analysed using MMS analysis software (version 9.1). Measures of peristaltic integrity (largest break and total break size in cm of the 20mmHg isobar) were derived. Pressure-flow analysis was performed using purpose designed MATLAB-based software (AIMplot, T. Omari) which derived peak pressure (PeakP), intra-bolus pressure (IBP), bolus flow relative to peak pressure (PNadImp) and its timing to peak pressure (TNadImp-PeakP). In addition the pressure-flow index (PFI), a composite measure of bolus pressurisation relative to flow and the impedance ratio (IR) a measure of the extent of bolus clearance failure were calculated. Results: Out of 220 swallows, 214 were suitable for analysis. A strong correlation between total break size and the largest break in the isobaric contour was found (r=0.846,p=0.000). There was a trend towards larger break size and higher IR, with a stronger correlation for the largest break (table 1). Both largest break and total break size correlated with lower PeakP, lower PNadImp, lower IBP and longer TNadImp-PeakP. However, no correlation was found between larger break size and PFI. Conclusion: Largest break and total break size seem to characterize peristaltic integrity equally. Larger break size is associated with lower peristaltic pressurization and impaired bolus movement. There seems to be little quantifiable difference between the largest break and total breaksize in relation to bolus pressurization. Esophageal break size and AIM-derived pressure-flow metrics

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Shiko Kuribayashi

Medical College of Wisconsin

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Shiko Kuribayashi

Medical College of Wisconsin

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