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Biomedical subjects

K Akimoto

Publications and source records attributed to K Akimoto.

At least 163 records · Page 9Linked to original sources
PubMed1990

Aortic regurgitation: ventricular response after aortic valve replacement.

This study was designed to evaluate the usefulness of the ratio of the preoperative regurgitant stroke volume to left ventricular end-diastolic volume (RSV/LVEDV) for assessing the left ventricular function preoperatively. In 26 patients with aortic regurgitation (AR), the percent decrease in LVEDV was compared with the preoperative RSV/LVEDV, ejection fraction (EF), LVEDV, left ventricular end-systolic volume (LVESV) or left ventricular end-diastolic pressure (LVEDP). There was a significant correlation between the percent decrease in LVEDV and RSV/LVEDV. Patients with RSV/LVEDV of more than 0.26 had a significantly smaller postoperative left ventricular end-diastolic volume index (LVEDVI) and left ventricular end-systolic volume index (LVESVI), and a greater postoperative EF than patients with smaller RSV/LVEDV. All but one patient with RSI/LVEDVI larger than 0.0016 LVEDVI had normal postoperative LVEDVI. Based on these findings, it is concluded that the RSV/LVEDV is an useful indicator for preoperative evaluation of left ventricular functions in patients with AR. Surgical intervention for patients with AR should be recommended before the RSI/LVEDVI drops to less than 0.0016 LVEDVI, to expect good postoperative ventricular responses.

Adult↗
PubMed1990

Effects of chelated sera and alteration in calcium concentration on the growth of oral epithelial cells in primary culture.

The purpose of this study were to examine the distribution of growth-promoting activity of some chelated sera and to investigate the relationship between calcium concentration in culture medium and the growth-promoting activity of the chelated sera in comparison with that of the original serum. Results showed that the chelated serum obtained by acidic resin treatment promoted colony formation, while the number of colonies decreased in cultures containing either dialyzed serum or chelated one obtained by treatment with alkaline resin. The acid-chelated serum and its lyophilized materials maintained the growth-promoting activity for 6 months or more in a deep freezer. This activity depended on the calcium concentration of culture medium in the range from 0.06 to approximately 1.5 mM. The optimal concentration of this material for growth promotion was 4 mg/ml as the protein density, which was about a quarter of that for the original serum protein. Sera from different sources treated with the acidic resin also showed similar effect on the growth. This finding strongly suggests that the acid-chelated serum and its lyophilized protein contain a keratinocyte growth factor(s).

Animals↗
PubMed1990

[Optimal calcium concentration for the proliferation of oral mucosal epithelial cells from adult rabbit in vitro].

We studied a primary culture of oral epithelial cells from adult rabbit and reported about dose-dependent growth by Ca increase. Therefore, in the present study we examined the relationship between total Ca, or Ca ion concentration and the proliferation of oral epithelial cells. The results were as followings. 1. The optimal Ca concentration for the growth in primary culture of oral epithelial cells was affected by the serum concentration in the medium. But Ca ion concentration for the best growth was in 10-30 micrograms/ml (0.25-0.74 mM) regardless of the serum concentration. 2. The optimal Ca ion concentration was shifted to 3-20 micrograms/ml (0.075-0.5 mM) in the medium containing chelated serum. This fact, suggests that the chelated serum may play different action from whole serum. 3. The optimal Ca ion concentration in the present study was higher density region than Hennings's view (0.04-0.1 mM) and it was lower than that of Tong (1.4-2.8 mM). Our data coincided with that of Wille (0.18-0.36 mM) who used MCDB 153 medium.

Animals↗
PubMed1990

Exercise-induced anaphylaxis: improvement after removal of amalgam in dental caries.

We present a case of exercise-induced anaphylaxis with improvement following the removal of dental amalgam. Although her symptoms were unresponsive to various kinds of therapy until removal of the amalgam, her symptoms related to exercise improved remarkably after the removal. The increase in plasma histamine levels for exercise provocation test also improved. This suggests that sensitivity to metals might cause exercise-induced asthma in some patients.

Anaphylaxis↗
PubMed1989

Subchronic cocaine treatment enhances cocaine-induced dopamine efflux, studied by in vivo intracerebral dialysis.

Repeated administration of cocaine in animals results in behavioral sensitization. In order to investigate the neurochemical mechanism underlying such behavioral sensitization, we designed the following two experiments. In both experiments, rats were pretreated with cocaine (20 mg/kg i.p.) or saline, once daily for 14 consecutive days. Exp. 1: 7 days after withdrawal from the drug, the stereotyped behavioral response to a challenge of cocaine (20 mg/kg i.p.) was measured. Exp. 2: 7 days after withdrawal from the drug, we measured extracellular dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) after the challenge administration of cocaine using an in vivo intracerebral dialysis technique. The rats pretreated with cocaine (20 mg/kg i.p.) exhibited behavioral augmentation in response to a challenge of cocaine. The challenge administration of cocaine caused an increase in DA and a decrease in DOPAC. The DA level in the striatal perfusates of the cocaine-pretreated rats was significantly greater than that in the saline-pretreated rats. These results suggest that the increased extracellular DA concentration in the striatum plays an important role in the cocaine-induced behavioral sensitization.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1989

Subchronic methamphetamine treatment enhances methamphetamine- or cocaine-induced dopamine efflux in vivo.

Intracerebral dialysis was used to study the mechanism underlying behavioral sensitization. Rats were divided into two groups: a control group that received intraperitoneal injections of saline and an experimental group that was given methamphetamine (MAP) (4 mg/kg) once a day for 14 days. Seven days after the last injection, dopamine (DA) and its metabolites were measured in striatal dialysates obtained from awake freely moving rats. A challenge injection of MAP (4 mg/kg) caused a marked increase in the extracellular concentrations of DA, and the extent of the increase was significantly greater in MAP-pretreated rats than in the saline-pretreated controls. A challenge injection of cocaine (20 mg/kg) also caused a significantly greater increase in extracellular DA levels in MAP-pretreated rats than in saline-pretreated rats. These results suggest that an enhancement in striatal DA efflux may play an important role in MAP-induced behavioral sensitization and cross-sensitization to cocaine.

Animals↗
PubMed1989

Quantitative analysis of trazodone hydrochloride in tablets by an ion-selective electrode.

A simple assay procedure for the quantitation of trazodone hydrochloride in tablets, without prior separation, has been developed using a trazodone-selective electrode. The electrode was based on a trazodone:tetrakis(p-chlorophenyl)borate ion-pair complex, dioctyl phthalate, and polyvinyl chloride matrix that were mounted on a PTFE membrane. The electrode showed a near-Nernstian response in the range of 10(-2) to 5 x 10(-6) M trazodone over the pH range of 2.5 to 5.0, with a cationic slope of 58 mV/concentration decade. The durability of the electrode and the reproducibility of the performance among the electrodes were sufficient. The electrode was used for the determination of the pKa value of trazodone. The selectivity of the electrode to a number of interferences was investigated. Many inorganic cations (alkali and alkaline earth metals) and pharmaceutical excipients did not interfere, but some organic ammonium compounds interfered according to their extractability. Determination of 10 to 3000 micrograms/mL of trazodone hydrochloride in aqueous solution showed an average recovery of 100.6% (mean standard deviation 0.4%) by direct potentiometry. This assay was applied to determine trazodone hydrochloride in tablets and the results compared favorably with those obtained by high-performance liquid chromatography.

Chromatography, High Pressure Liquid↗
PubMed1989

Clinical features of aortic arch anomaly with malalignment ventricular septal defect.

The clinical features and outcome after various surgical procedures on 9 patients with coarctation or interruption of the aortic arch and malalignment ventricular septal defect (group 1) were compared with those of 9 patients with the arch anomaly without malalignment ventricular septal defect (group 2). Cardiomegaly and metabolic acidosis were prominent in group 1. Five of the 9 patients in group 1 died in the immediate postoperative period (56% mortality), but no operative deaths occurred among 8 patients in group 2 (p less than 0.01). The ratio of left ventricular outflow tract to ascending aortic diameter was 0.59 +/- 0.09 in group 1 and 1.03 +/- 0.11 in group 2 (p less than 0.01). Three of 4 patients with a ratio of less than 0.6 died, but no operative deaths occurred among the 6 patients who had a palliative operation and in whom the ratio was more than 0.6. These data suggest that left ventricular outflow tract obstruction is critical when the ratio of left ventricular outflow tract to ascending aortic diameter is 0.6 or less. The presence of severe left ventricular outflow tract obstruction necessitates modification of the present surgical strategy.

Abnormalities, Multiple↗
PubMed1989

Release of high molecular weight-neutrophil chemotactic activity from human tissues, cells and secretion.

Release of high molecular weight-neutrophil chemotactic activity from human tissues, cells and secretion was studied in vivo and in vitro. Lung, nasal turbinate, nasal polyps, skin of neurofibromatosis, basophils from chronic myeloid leukemia and cultured basophilic cells from cord blood released this mediator following calcium ionophore, antigen, anti-IgE or homogenization in vitro. Its release was also demonstrated in human nasal secretions from patients with allergic rhinitis following antigen challenge. Regarding mononuclear cells no release of this mediator was observed from normal donors or asthmatic patients having no active attack upon challenge with calcium ionophore, phytohemagglutinin or antigen. Homogenized duodenum released high molecular weight-neutrophil chemotactic activity but less activity in comparison with other tissues or cells mentioned above.

Asthma↗
PubMed1989

[Contents and molecular forms of human atrial natriuretic peptide in right and left auricle in patients with heart disease].

Contents and molecular forms of human atrial natriuretic peptide (hANP) in right and left auricle were analyzed by reverse phase high liquid chromatography (RP-HPLC), coupled with radioimmunoassay for hANP. Analyses were done with auricles taken from 4 autopsied cases without heart disease, and 13 patients with heart disease. Both right and left auricular hANP contents in patients with heart disease were higher than those obtained at autopsy. In patients with mitral stenosis (MS) or mitral regurgitation (MR) who have left atrial pressure and/or volume overload, hANP contents in left auricle were higher than those in right auricle. In addition, three types of molecular forms of hANP, (gamma) type, (alpha, beta, gamma) type, (beta, gamma) type, were observed in both right and left atrium. In patients with MS or MR, (beta, gamma) type or (alpha, beta, gamma) type which have beta-hANP immunoreactivity were observed in 8 out of 9 in patients in left auricle, however, in 4 out of 9 patients in right auricle. Our results suggested that the difference of contents and molecular forms of hANP may reflect the pathophysiological role in heart diseases.

Adult↗
PubMed1989

How to prevent allergic disease. I. Study of specific IgE, IgG, and IgG4 antibodies in serum of pregnant mothers, cord blood, and infants.

We have investigated methods for decreasing the number of allergic patients and have produced the following data. We compared mothers' total IgE levels and allergen-specific IgG and IgG4 levels in 72 paired cases. In mothers with high total IgE, the cord blood levels of IgG and IgG4 specific for egg, milk, and mite allergens were significantly higher than in mothers with low IgE levels. Mothers who took over 200 ml of milk per day showed a statistically higher level of milk-specific IgG antibody. From our studies of IgE, IgG, and IgG4 antibody levels in atopic dermatitis patients, we conclude that specific IgG and IgG4 levels should be considered when eliminating offending foods. Infants with high egg-specific IgG antibody levels in cord blood were statistically more prone to develop allergic disease.

Eggs↗
PubMed1989

[Studies of specific IgE and IgG antibodies in allergic children. Changes in specific IgE and IgG antibodies to egg white, milk, soybean and mite from children with atopic dermatitis].

Egg, milk, soybean, mite (DF)-specific IgG and IgE antibodies were measured in 276 atopic dermatitis children in whom dietary restrictions had never been done. We recommend cleaning house and bed clothes to decrease number of mites and elimination diet according to clinical symptoms and laboratory findings. After elimination periods (approximately 140 days) the same specific antibodies were examined again. In the patients who improved clinically by elimination of foods, the specific IgG antibodies to the foods decreased significantly. The other patients did not improved clinically suggesting that inadequate elimination diet were done and cleaning house and bed clothes was incomplete and/or other types of allergic reactions might exist.

Animals↗
PubMed1989

[Basic analysis of extracorporeal shock wave lithotripsy of gallstones].

Influence of extracorporeal shock wave lithotripsy (ESWL) on human gallstones placed in dog gallbladders was investigated. After irradiation of shock wave more than 600 times, maximal diameter of residual stones of 10 mm before irradiation was destroyed to 2 mm or less. Levels of serum transaminase (GOT.GPT) were elevated, in parallel with times of shock waves. These results suggested that 600 times of shock waves were enough to destroy one cholesterol stone, diameter of which was about 1 cm. Data of elevation of serum transaminase showed that more than 600 times of shock waves were possible to induce the damage of liver.

Alanine Transaminase↗