Biomedical subjects

K Matsuyama

Publications and source records attributed to K Matsuyama.

At least 19 recordsLinked to original sources

PubMed2003

Slowly developing perigraft seroma after a modified Blalock-Taussig shunt.

We report a 26-year-old patient with slowly developing perigraft seroma 15 years after a modified Blalock-Taussig shunt with an expanded polytetrafluorethylene graft. The mediastinal mass was first observed on a chest x-ray film 8 years after the shunt operation. The mass contained massive gelatinous or organic tissues with a severely calcified pseudocapsule, and it was adjacent to the calcified but functioning graft. No fluid collections were noted. The histological findings were compatible with a seroma. No recurrence was noted on last follow-up 1 year postoperatively.

Adult↗

PubMed2001

Environmentally benign formation of polymeric microspheres by rapid expansion of supercritical carbon dioxide solution with a nonsolvent.

A novel method is reported for forming polymer microparticles, which reduce atmospheric emissions of environmentally harmful volatile organic compounds such as toluene and xylene used as paint solvent in paint industry. The polymer microparticles have formed through rapid expansion from supercritical solution with a nonsolvent (RESS-N). Solubilization of poly(styrene)-b-(poly(methyl methacrylate)-co-poly (glycidyl methacrylate)) copolymer(PS-b-(PMMA-co-PGMA), MW = 5000, PS/PMMA/PGMA = 2/5/3), poly(ethylene glycol) (PEG, M. W = 4000), bisphenol A type epoxy resin (EP, MW = 3000), poly(methyl methacrylate) (PMMA; MW = 15000, 75000, 120000), and poly(oxyalkylene) alkylphenyl ether (MW = 4000) in carbon dioxide (CO2) was achieved with the use of small alcohols as cosolvents. The solubility of the PS-b-(PMMA-co-PGMA) is extremely low in either CO2 or ethanol but becomes 20 wt % in a mixture of the two. Because ethanol is a nonsolvent for the polymer, it can be used as a cosolvent in rapid expansion from supercritical solution to produce 1-3 microm particles that do not agglomerate. Obtained polymer particles by RESS-N were applied as powder coatings. The resulting coatings have a smooth and coherent film. The particle size distribution of microspheres was controlled by changing the polymer concentration, preexpansion pressure, temperature, and injection distance. The feed compositions were more effective than the other factors in controlling the particle size. The polymeric microparticles formed by RESS-N method can be utilized to make the thin coating film without anytoxic organic solvents and/or surfactants.

Absorption↗

PubMed2001

High-fidelity transmission acquired via a developmental decrease in NMDA receptor expression at an auditory synapse.

Central auditory relay synapses in mature animals follow high-frequency inputs for computation of sound localization. In immature mice, however, transmission at the calyx of Held synapse in auditory brainstem was inaccurate for high-frequency inputs because the summed slow synaptic potential components caused aberrant firings or blocked action potentials. As the mice matured, synaptic potentials became shorter, with smaller and faster NMDA receptor components, thereby establishing the precise one-to-one transmission for high-frequency inputs. Developmental acquisition of this high-fidelity transmission could be mimicked experimentally in immature mice by blocking NMDA receptors with d(-)2-amino-5-phosphonovaleric acid (d-APV). Furthermore, bilateral cochlear ablations at postnatal day 7 (P7) attenuated the developmental decrease of NMDA receptor expression and prevented the acquisition of high-fidelity transmission. We suggest that auditory activity, which begins at P10-P12 in mice, downregulates the expression of postsynaptic NMDA receptors, thereby contributing to the establishment of high-fidelity synaptic transmission.

2-Amino-5-phosphonovalerate↗

PubMed2001

The inducible nitric oxide synthase inhibitor ONO-1714 blunts dextran sulfate sodium colitis in mice.

In mice with acute dextran sulfate sodium colitis, we examined the effect of inducible nitric oxide synthase inhibition by (1S,5S,6R,7R)-7chloro-3-amino-5methyl-2-azabicyclo[4.1.0]heptane hydrochloride (ONO-1714) on colonic biochemistry, injury, and inflammation. Colonic luminal nitrate and nitrite were measured by the Griess reaction; inducible nitric oxide synthase messenger RNA expression by reverse transcription-polymerase chain reaction; and nitrotyrosine by immunohistochemistry. Mice with colitis showed increases in nitrate and nitrite, inducible nitric oxide synthase messenger RNA, and numbers of cells staining for nitrotyrosine. Colonic inflammation was severe. ONO-1714 inhibited increases in nitrate and nitrite and numbers of nitrotyrosine-positive cells; injury and inflammation also were reduced. Dextran sulfate sodium-induced increases in thiobarbituric acid-reactive substances, a lipid peroxidation marker, were blunted by ONO-1714, which also inhibited increases in mucosal inflammatory cytokines. Nitric oxide produced by inducible nitric oxide synthase may contribute to colonic inflammation by nitrosation, oxidative damage, and enhanced inflammatory cytokines.

Amidines↗

PubMed2001

Surgery for acute type A aortic dissection using retrograde cerebral perfusion.

OBJECTIVE: We reviewed the surgical management of acute type A aortic dissection between 1989 and 1998. METHODS: Subjects were 28 consecutive patients (mean age: 61.8 +/- 10.7 years) with acute type A aortic dissection were studied. The mean duration between aortic dissection onset and surgery was 17.5 +/- 17.0 hours. In surgery, aortic pathology and flow patterns in dissected aortic channels were evaluated using transesophageal and epiaortic echo. Simple, safe combination of profound hypothermic circulatory arrest with retrograde cerebral perfusion and open aortic anastomosis was used for brain protection. Hypothermic circulatory arrest was 46.9 +/- 24.8 minutes. Aortic repair consisted in ascending aortic replacement in 5 patients, with hemiarch repair in 17, and total arch repair in 6. Intimal tears were resected in all but 2 patients. Concomitantly resuspension of the aortic valve was done in 9 and aortic root replacement in 2. RESULTS: No operative (30-day) deaths occurred, although 2 died from unrelated hepatic failure during hospitalization or late-stage pancreatic cancer in the late stage. In cerebral sequellae, 1 patient suffered a stroke and 2 patients developed temporary neurologic dysfunction. CONCLUSION: Our experience demonstrated that the simplified conjunction of hypothermic circulatory arrest with retrograde cerebral perfusion and open aortic anastomosis, associated with real-time assessment by transesophageal and epiaortic echo, is safe and useful during emergency aortic repair for acute type A aortic dissection.

Acute Disease↗

PubMed2001

Coronary artery bypass grafting for patients with an atherosclerotic ascending aorta.

OBJECTIVES: We review the outcome of coronary artery bypass grafting in patients with a severe atherosclerotic ascending aorta. METHODS: Subjects were 31 patients averaging 69.4 +/- 6.9 years old studied from 1990 through 1998. Ascending aortic lesions were assessed using epiaortic echo and 2 types of aortic nonclamping techniques applied. In 29 patients operated on in the early years, bypass grafting was conducted on the hypothermic fibrillated heart in 22 and on the beating heart in 7. The remaining 2 underwent off-pump coronary artery bypass grafting more recently. For cases with multivessel disease, we used composite grafting. RESULTS: Three patients developed mild stroke and 5 died within 30 days of surgery--4 from multiple emboli (1 accompanied by a stroke) and 1 from perioperative myocardial infarction. One hospital death occurred due to brain damage and multiorgan failure following unexpected rupture of a saphenous vein graft. No cardiac deaths occurred in the late stage of our series. Actuarial survival was 73.0% for 3 years and 68.0% for 5 years. Freedom from cardiac events was favorable in the remaining 25 survivors. CONCLUSIONS: Outcome was suboptimal for the risks involved. Recent technical advances, including coronary surgery on the beating heart with or without cardiopulmonary bypass using variable in-situ or free arterial grafts, associated with adequate evaluation of systemic atherosclerosis, should improve this outcome.

Aged↗

PubMed2001

Pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation.

Right atrial isomerism is well known to be associated with anomalous pulmonary venous drainage and a potentially dangerous sequel to pulmonary venous obstruction, and is associated with high mortality. We report a 16-month-old girl with pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation. Two years after surgery, she is doing well with 80% oxygen saturation and no further episodes of hemoptysis.

Cardiac Surgical Procedures↗

PubMed2001

Hyperamylasemia and subclinical pancreatitis after cardiac surgery.

Hyperamylasemia after cardiac surgery is common but typically causes no clinical concern because it consists mainly of the salivary isoenzyme. In this study we evaluated the incidence, source, and time course of postoperative hyperamylasemia with special attention to the possibility of subclinical pancreatitis. In 88 patients prospectively tested for serum amylase and lipase concentrations, elastase 1 activity, and amylase isoenzyme characteristics, 57 (64%) showed hyperamylasemia during the early postoperative period. In most cases early hyperamylasemia was not of pancreatic origin, but two patients were diagnosed with subclinical pancreatitis. Among the last 23 patients, 5 of 10 patients with early hyperamylasemia exceeding 1000 IU/L showed late hyperamylasemia on the seventh postoperative day, when it represented mainly the pancreatic isoenzyme. Lipase concentrations and elastase 1 activities were elevated in these cases. Late hyperamylasemia following cardiac surgery may be of pancreatic origin and indicative of subclinical pancreatitis, even if early hyperamylasemia was of salivary origin.

Adult↗

PubMed2001

Postoperative evaluation of pylorus-preserving procedures compared with conventional distal gastrectomy for early gastric cancer.

We evaluated postoperative function in 98 patients who underwent surgery for early gastric cancer between 1995 and 1998 to compare the results of pylorus-preserving procedures to those of conventional distal gastrectomy with Billroth I (B-I). The pylorus-preserving procedures included endoscopic mucosal resection (EMR), performed in 12 patients; local resection (Local), performed in 14 patients; segmental resection (Seg), performed in 8 patients; and pylorus-preserving gastrectomy (PPG), performed in 19 patients. B-I was performed in 45 patients. The nutritional status and serum albumin (Alb) levels after PPG, the hemoglobin (Hb) levels after EMR, Local, and PPG, and the present/preoperative body weight ratios after EMR, Local, Seg, and PPG were superior to those after B-I. The time before oral intake was recommenced after EMR and Local, the volume of oral intake tolerated after EMR, Local, Seg, and PPG, and the postoperative hospital stay after EMR were all superior to those after B-I. Moreover, significantly fewer patients suffered reflux symptoms after EMR, Local, and PPG, abdominal fullness after EMR, and early dumping syndrome after EMR, Local, and PPG than after B-I. There was also less evidence of gastritis after EMR, Local, and PPG, and of bile reflux after EMR, Local, and PPG, than after B-I. These findings indicate that pylorus-preserving procedures may result in a better postoperative quality of life for selected patients with early gastric cancer.

Adult↗

PubMed2001

Medullary reticulospinal tract mediating the generalized motor inhibition in cats: parallel inhibitory mechanisms acting on motoneurons and on interneuronal transmission in reflex pathways.

The present study was designed to elucidate the spinal interneuronal mechanisms of motor inhibition evoked by stimulating the medullary reticular formation. Two questions were addressed. First, whether there is a parallel motor inhibition to motoneurons and to interneurons in reflex pathways. Second, whether the inhibition is mediated by interneurons interposed in known reflex pathways. We recorded the intracellular activity of hindlimb motoneurons in decerebrate cats and examined the effects of medullary stimulation on these neurons and on interneuronal transmission in reflex pathways to them. Stimuli (three pulses at 10-60microA and 1-10ms intervals) delivered to the nucleus reticularis gigantocellularis evoked inhibitory postsynaptic potentials in alpha-motoneurons (n=147) and gamma-motoneurons (n=5) with both early and late latencies. The early inhibitory postsynaptic potentials were observed in 66.4% of the motoneurons and had a latency of 4.0-5.5ms with a segmental delay of more than 1.4ms. The late inhibitory postsynaptic potentials were observed in 98.0% of the motoneurons and had a latency of 30-35ms, with a peak latency of 50-60ms. Both types of inhibitory postsynaptic potentials were evoked through fibers descending in the ventrolateral quadrant. The inhibitory postsynaptic potentials were not influenced by recurrent inhibitory pathways, but both types were greatly attenuated by volleys in flexor reflex afferents. Conditioning medullary stimulation, which was subthreshold to evoke inhibitory postsynaptic potentials in the motoneurons, neither evoked primary afferent depolarization of dorsal roots nor reduced the input resistance of the motoneurons. However, the conditioning stimulation often facilitated non-reciprocal group I inhibitory pathways (Ib inhibitory pathways) to the motoneurons in early (<20ms) and late (30-80ms) periods. In contrast, it attenuated test postsynaptic potentials evoked through reciprocal Ia inhibitory pathways, and excitatory and inhibitory pathways from flexor reflex afferent and recurrent inhibitory pathways. The inhibitory effects were observed in both early and late periods. The present results provide new information about a parallel inhibitory process from the medullary reticular formation that produces a generalized motor inhibition by acting on alpha- and gamma-motoneurons, and on interneurons in reflex pathways. Interneurons receiving inhibition from flexor reflex afferents and a group of Ib interneurons may mediate the inhibitory effects upon motoneurons.

Animals↗

PubMed2001

Aortic arch repairs through three different approaches.

OBJECTIVES: The outcome of aortic arch repairs by means of three different approaches between 1990 and January 2000 was reviewed. METHODS: In total 39 patients aged 71.5+/-6.2 years were operated on. The three different surgical approaches depended on the anatomical positions of the aneurysms and on their proximal or distal extension; a median approach was employed in 23 patients, whereas a left postero-lateral approach was used in eight patients. More recently, in eight cases a left antero-lateral approach was applied. All patients underwent open aortic anastomosis without any clamp on or around the aortic arch. During the procedure, the brain was protected by a combination of profound hypothermic circulatory arrest and several techniques of retrograde cerebral perfusion. RESULTS: Permanent cerebral dysfunction occurred in four patients: two in the median approach and two in the left postero-lateral approach. There were two hospital deaths (5.3%) and six late deaths, all of which belonged either to the median group or to the postero-lateral group. The antero-lateral approach did not produce any cerebral dysfunction, early death, or late death. CONCLUSIONS: The outcome of aortic arch repairs using profound hypothermic circulatory arrest and variable techniques of retrograde cerebral perfusion, by means of three different approaches, was satisfactory. Of the three approaches, the antero-lateral approach can be employed easily, whether aneurysms extend proximally or distally.

Aged↗

PubMed2001

Effects of polaprezinc on lipid peroxidation, neutrophil accumulation, and TNF-alpha expression in rats with aspirin-induced gastric mucosal injury.

We examined the roles of lipid peroxidation, neutrophil accumulation, and inflammatory cytokines in the protective effect of polaprezinc against aspirin-induced gastric mucosal injury in rats. The intragastric administration of acidified aspirin induced hyperemia and hemorrhagic erosions in rat stomachs. The increase in the total gastric erosive area after aspirin administration was significantly inhibited in a dose-dependent manner by treatment with polaprezinc. The increases in thiobarbituric acid-reactive substances and tissue-associated myeloperoxidase activity 3 hr after aspirin administration were significantly inhibited by pretreatment with polaprezinc. The gastric concentration of TNF-alpha increased after aspirin administration, and the increase was also inhibited in a dose-dependent manner by treatment with polaprezinc. The peak expression of TNF-alpha mRNA 1 hr after aspirin administration was inhibited by 30 mg/kg of polaprezinc. Based on these data, the beneficial effects of polaprezinc on aspirin-induced gastric mucosal injury may be attributed to its antioxidative and antiinflammatory properties.

Animals↗

PubMed2001

Pioglitazone, a specific PPAR-gamma ligand, inhibits aspirin-induced gastric mucosal injury in rats.

BACKGROUND: Neutrophils activation and tumour necrosis factor-alpha (TNF-alpha) induction play a critical role in aspirin-induced gastric mucosal injury. Peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, has recently been implicated as a regulator of inflammatory responses. The aim of the present study was to determine whether pioglitazone, a specific PPAR-gamma ligand, can ameliorate aspirin-induced gastric mucosal injury in rats, and whether the agent can inhibit the increase in neutrophil accumulation associated with TNF-alpha expression. METHODS: Aspirin-induced injury was produced by the intragastric administration of aspirin (200 mg/kg) and HCl (0.15 N, 8.0 mL/kg). Pioglitazone was given to the rats by gastric intubation 1 h before the aspirin administration. Thiobarbituric acid-reactive substances and tissue-associated myeloperoxidase activity were measured in gastric mucosa as indices of lipid peroxidation and neutrophil infiltration. The gastric concentration of TNF-alpha and the expression of TNF-alpha mRNA was determined by ELISA and reverse transcriptase-polymerase chain reaction. RESULTS: The intragastric administration of acidified aspirin induced hyperemia and haemorrhagic erosions in rat stomachs. The increase in the total gastric erosive area after aspirin administration was significantly inhibited by treatment with pioglitazone in a dose-dependent manner. The increases in thiobarbituric acid-reactive substances and myeloperoxidase activity after aspirin administration were both significantly inhibited by pre-treatment with pioglitazone (10 mg/kg). The gastric content of TNF-alpha increased and the expression of TNF-alpha mRNA was up-regulated after aspirin treatment. However, the peak TNF-alpha mRNA expression 1 h after aspirin administration was inhibited by pioglitazone. CONCLUSION: Based on these data, the beneficial effects of pioglitazone on aspirin-induced gastric mucosal injury may be attributed to its anti-inflammatory properties.

Animals↗

PubMed2001

Variation of des-gamma-carboxyprothrombin (PIVKA-II) levels in cord blood throughout gestation.

The variation of des-gamma-carboxyprothrombin (PIVKA-II, protein induced by vitamin K absence) levels in umbilical cord blood throughout gestation was examined using a highly sensitive method, electrochemiluminescence immunoassay (ECLIA). PIVKA-II levels in infants without any complications were low, but modestly high, exceeding the normal range of healthy adults during the preterm period, followed by a remarkable increase after the 37th week of gestation. Among infants complicated with severe preeclampsia a marked increase of PIVKA-II levels was observed in preterm infants, showing a good correlation with the existence ofinfarctions on the placenta. On the other hand, among infants complicated with preterm premature rupture of the membranes (PROM) in which antibiotics were administered during the prenatal period, a moderate elevation of PIVKA-II levels was observed. These data suggest that the normal range of PIVKA-II in fetuses is modestly high compared with adults and any deficient status of vitamin K would not exist throughout the preterm period. Nevertheless, the vitamin K status might readily fall into a deficient condition in term infants. Furthermore, it is notable that vitamin K deficiency would be induced in complicated gestation with severe preeclampsia and medication with antibiotics.

Biomarkers↗

PubMed2001

Early and late results of partial plication annuloplasty for congenital mitral insufficiency.

BACKGROUND: Partial plication annuloplasty is the main technique for congenital mitral insufficiency because this technique allows the mitral anulus to grow, in contrast to ring annuloplasty. However, this technique is not satisfactory for mitral insufficiency with some anomalies of the mitral valve apparatus. METHODS: Forty-one patients underwent partial plication annuloplasty for mitral regurgitation from July 1979 to December 1998. Mitral regurgitation associated with an atrioventricular defect, an atrioventricular discordance, and a univentricular heart was excluded from this study. RESULTS: There were no early or late deaths. In early results, partial plication annuloplasty was more effective for mitral regurgitation with abnormality of the posterior leaflet (n = 14) or normal leaflet motion (n = 8) than with abnormality of the anterior leaflet and its apparatus (n = 14) or absence of chordae (n = 4). The mean follow-up period was 145.8 months. During the follow-up period, 2 patients underwent mitral valve replacement, and a third patient underwent mitral valve repair with partial plication annuloplasty after the first repair. The main cause of mitral regurgitation of 2 of the 3 patients was absence of chordae. The actuarial freedom from reoperation rate was 94.9% +/- 3.6%, 91.9% +/- 4.7%, and 91.9% +/- 4.7% at 5, 10, and 15 years after the operation, respectively. CONCLUSION: Early and long-term results of partial plication annuloplasty were acceptable for congenital mitral insufficiency with any type of malformation of the mitral valve, and results were excellent with abnormality of the posterior leaflet and its apparatus or normal leaflet motion. However, late results were suboptimal for mitral regurgitation with absence of chordae. Other techniques, such as artificial chorda replacement, should be adapted in these cases.

Actuarial Analysis↗

PubMed2001

Preparation and characterization of biodegradable or enteric-coated microspheres containing the protease inhibitor camostat.

We have produced biodegradable or enteric-coated microspheres containing camostat mesylate, a protease inhibitor, using a water-oil-water emulsion solvent evaporation method. The characteristics of the microspheres were determined. When polylactic acid, a biodegradable polymer, was used as a wall material, the optimized microsphere obtained showed a loading efficiency of almost 95% and had a mean diameter of 30 microm. This microsphere showed a sustained-release profile, with nearly 25% of drug being released at seven days in a dissolution test. When hypromellose acetate succinate (AS-HG type, with a high content of succinyl group) was used as an enteric wall material, optimized microspheres showed a loading efficiency of almost 80%. In this case, pH 3.0 citrate buffer was used as an internal aqueous phase, and citrate buffer containing 0.5% polyvinylalcohol was used as the external aqueous phase. These microspheres showed a rapid release profile in pH 6.8 buffer, whereas the release was extremely slow in pH 1.2 buffer. Hypromellose acetate succinate microspheres were also prepared containing 10% (w/w) N-benzoyl-dl-arg-4-nitroanilide as a model substrate for trypsin, with or without 5% (w/w) camostat. These microspheres were incubated in pH 6 or 7 buffer containing trypsin at 37 degrees C. When camostat was included in the microspheres, the substrate was protected from attack by trypsin, while in the absence of camostat, the released substrate was immediately attacked by trypsin to produce the degradation product N-benzoyl-dl-arginine.

Buffers↗

PubMed2001

Preparation and characterization of insulin-loaded acrylic hydrogels containing absorption enhancers.

The objectives of this study were to prepare insulin-loaded acrylic hydrogel formulations containing various absorption enhancers, to perform in vitro and in vivo characterization of these formulations, and to evaluate the factors which affecting insulin availability on rectal delivery of insulin using this hydrogel system. The acrylic block copolymer of methacrylic acid and methacrylate, Eudispert, was used to make the hydrogel formulations. As absorption enhancers, 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-CyD), lauric acid (C12), or the sodium salt of C12 (C12Na), were incorporated into the hydrogels. In an in vitro release test, the release rate of insulin from the hydrogels decreased as the polymer concentration of the hydrogel increased. The addition of C12Na to the hydrogel further increased the insulin release rate, which was greater at higher concentrations of the enhancer. A portion of the C12Na was found to remain bound to the acrylic polymer in dissolution medium. Serum insulin levels were determined at various time points after the administration of insulin solution or insulin-loaded (50 units/kg body weight) Eudispert hydrogels containing 5% (w/w) of C12, C12Na, or DM-beta-CyD to in situ loops in various regions of the rat intestine. The most effective enhancement of insulin release was observed with formulations containing C12Na. The bioavailability of insulin from the hydrogels was lower than that from the insulin solutions. Hydrogel formulations containing 7% or 10% Eudispert remained in the rectum for 5 h after rectal administration. However, the 5% (w/w) C12Na solution stained with Evan's-blue had diffused out and the dye had reached the upper intestinal tract within 2 h. Finally, the rectal administration of insulin-loaded hydrogels, containing 4%, 7%, or 10% (w/w) Eudispert and 5% (w/w) of enhancer (C12, C12Na, or DM-beta-CyD) to normal rats was shown to decrease serum glucose concentrations. The greatest effect was found with insulin-loaded 7% (Eudispert) hydrogel containing C12Na which having cosiderable large insulin release rate and bioadhesive characteristics.

Acrylates↗

PubMed2001

A new method for evaluating the bitterness of medicines by semi-continuous measurement of adsorption using a taste sensor.

We describe a new method for the evaluation of the bitterness of medicines by semi-continuous measurement of adsorption using a multichannel taste sensor or 'electric tongue'. The bitterness of 10 basic medicines was evaluated by both the taste sensor and in human gustatory sensation tests with 11 volunteers. The sensor part of the taste sensor consists of eight electrodes made of lipid/polymer membranes. Three variables were obtained from the taste sensor data: sensor output (S), the change of membrane potential caused by adsorption, corresponding to aftertaste (C), and the ratio C/S. These variables were used to predict an estimated bitterness score in multiple regression analysis. Semi-continuous measurement of C (every 30 s up to 150 s) was adopted as an additional explanatory variable, and the attenuation rate of C was defined as C'. These data were also subjected to multiple regression analysis. The correlation coefficient (r) estimated for the bitterness score predicted by the taste sensor, using C' for channel 2 and C/S for channel 4, and the score obtained by human gustatory sensation, was 0.824. This value was greater than that obtained using C/S for both channels 2 and 4 (0.734). The method described in the present study seems to offer good predictability for the evaluation of bitterness.

Adsorption↗