Biomedical subjects

Y Okuno

Publications and source records attributed to Y Okuno.

At least 19 recordsLinked to original sources

PubMed1992

Thrombocytosis in patients with tumors producing colony-stimulating factor.

We investigated the cause of thrombocytosis in 14 patients with tumors producing colony-stimulating factor (CSF). Of the 14 patients, 10 had tumors producing granulocyte-CSF (G-CSF) and 4 had tumors producing granulocyte-macrophage--CSF (GM-CSF). Thrombocytosis of greater than 400 x 10(9)/L was noted in 8 of 10 patients with G-CSF-producing tumors and all 4 patients with GM-CSF-producing tumors. Median peak platelet counts were, respectively, 511 x 10(9)/L (range, 384 to 694 x 10(9)/L) and 579 x 10(9)/L (range, 526 to 910 x 10(9)/L) in patients with tumors producing G-CSF and GM-CSF. In most patients, thrombocytosis declined towards the terminal stage. High interleukin-1 (IL-1) and IL-6 levels were found in addition to CSFs in the plasma or culture supernatants of tumor cells obtained from most patients. In patients with GM-CSF-producing tumors, these specimens had megakaryocyte-CSF (Meg-CSF) activity, which was abolished by anti-GM-CSF antibody. These specimens also had megakaryocyte potentiating (Meg-Pot) activity attributable to both GM-CSF and IL-6. In patients with G-CSF-producing tumors, only Meg-Pot activity due to IL-6 was detected. These results indicate that the thrombocytosis in GM-CSF-producing tumors was caused by both the Meg-CSF activity of GM-CSF and the Meg-Pot activity of IL-6 plus GM-CSF, while that in G-CSF-producing tumors was due to the Meg-Pot activity of IL-6.

Adult↗

PubMed1992

Isolation and characterization of conglutinin as an influenza A virus inhibitor.

Normal horse and guinea pig sera contain alpha 2-macroglobulin which inhibits the infectivity and hemagglutinating activity of influenza A viruses of the H2 and H3 subtypes. On the other hand, normal bovine serum contains a component termed beta inhibitor that inhibits the infectivity and hemagglutinating activity of influenza A viruses of the H1 and H3 subtypes. To investigate the nature of the beta inhibitor of influenza A virus, we purified the conglutinin and examined its characteristics. First, we found a high correlation between the hemagglutination inhibition(HI) titer and conglutinin titer in several bovine sera (r = 0.906, p less than 0.005). The HI of bovine serum was mainly dependent on conglutinin because the HI activity was abrogated by N-acetylglucosamine but not by D-mannose. The conglutinin, purified from bovine serum, had neutralizing-activity as well as HI activity on influenza A viruses of the H1 and H3 subtypes. The HI activity of conglutinin was heat stable (56 degrees C, 30 min), Ca(++)-dependent, and resistant to both neuraminidase and periodate treatments. The HI activity of purified conglutinin was blocked by N-acetylglucosamine but not by D-mannose. The conglutinin was bound to hemagglutinin which had high mannose and complex sugar chains and its binding was inhibited by N-acetylglucosamine and dependent on divalent cations. These data indicate that the beta-like inhibitor activity of bovine serum is mainly dependent on conglutinin which inhibits hemagglutination and neutralizes the virus infectivity by its binding to a carbohydrate site at the HA.

Animals↗

PubMed1992

[Alteration of the ionized calcium level in coronary sinus blood during coronary arteriography].

Injection of contrast medium into the coronary circulation produces a decrease in the concentration of ionized calcium in blood and thus causes a deterioration of myocardial contractility. In this study, changes in the ionized calcium level in the coronary sinus during coronary arteriography were compared for four different contrast media in human subjects. The contrast media used were meglumine sodium diatrizoate, iohexol, iopamidol and meglumine sodium ioxaglate. Blood samples were collected from the coronary sinus before and 5, 15 and 30 seconds after the first injection of contrast medium into the left coronary artery. The ionized calcium level of each specimen was measured using an ion specific electrode, and hematocrit was measured using the centrifuge method. Diatrizoate produced the greatest changes in both hematocrit and ionized calcium. The time concentration curve of hematocrit was similar for all four contrast media, but diatrizoate and ioxaglate produced a prolonged decrease in ionized calcium. The cause of this phenomenon is not clear, but it may be related to differences in the ionic status of the contrast media. Nonionic low-osmolality contrast media with added calcium may be preferable for coronary arteriography with respect to maintenance of the ionized calcium level.

Adult↗

PubMed1992

Interleukin-5 in eosinophilic gastroenteritis.

During a 4-year period a 28-year-old female had 4 episodes of eosinophilia of over 10,000/mu 1; these episodes were associated with nausea, vomiting, diarrhea, and abdominal pain. On one occasion, she had ascites and pleural effusion which contained numerous mature eosinophils. On each occasion, these attacks disappeared within several weeks without any specific treatment. A diagnosis of eosinophilic gastroenteritis was made. A plasma sample obtained during the eosinophilia generated in vitro eosinophilic colonies when added to granulocyte/macrophage-progenitor (CFU-GM) cultures without exogenous growth factors. Colony formation was inhibited by anti-interleukin-5 (IL-5) antibody but not by antibodies toward IL-3, granulocyte colony-stimulating factor (G-CSF) or GM-CSF. A high plasma interleukin-5 (IL-5) level was noted when measured by enzyme-linked immunosorbent assay, while IL-3, G-CSF, and GM-CSF were undetectable. During remission the plasma gave negative results both for colony formation and IL-5 level. These results indicate that the eosinophilia of this disease is mediated by IL-5.

Adult↗

PubMed1992

Segmental gut transit in diabetes mellitus: effect of cisapride.

Gut transit using radiopaque markers was assessed in 5 healthy subjects and 24 diabetic patients. In the diabetics, various parameters including duration of the disease and diabetic complications, such as neuropathy, retinopathy and nephropathy, were determined, and the relationships between gut transit times and these complications were evaluated. The effect of cisapride on gut transit was studied in 10 diabetic patients. Large intestinal, descending colon, distal colon, and whole gut transit times were delayed in diabetics with autonomic neuropathy compared to controls and to diabetics without autonomic neuropathy (P less than 0.01). There was no difference in proximal colon transit times among them. An inverse correlation was observed between CVRR and the transit times for descending colon, distal colon, large intestine and whole gut. Large intestinal and whole-gut transit times were delayed in diabetics with retinopathy or with nephropathy compared to diabetics without those complications (P less than 0.01). In the diabetics, oral administration of 7.5 mg/day of cisapride for 2 weeks significantly accelerated descending colon transit (P less than 0.05) and partially accelerated distal colon, large intestinal and whole-gut transit. It is concluded that diabetics with autonomic neuropathy have delayed transits for the whole gut and that this finding is apparent to some extent in the distal colon but not in the proximal colon. Chronic oral administration of cisapride, a gastrointestinal prokinetic drug, was effective to improve these gastrointestinal motility disorders in diabetics with autonomic neuropathy.

Administration, Oral↗

PubMed1992

Nasal antibody response to mumps virus after vaccination and natural infection.

Nasopharyngeal secretions and sera were collected during an epidemic of mumps in a semi-closed institution. None of the children who received live attenuated mumps vaccine 5 months previously developed any symptoms of mumps. Neutralizing and IgA antibodies against mumps virus were measured by the peroxidase-antiperoxidase method and the fluorescent antibody to membrane antigen method, respectively. The immune responses in nasopharyngeal secretions and serum were studied in four groups (apparently infected, non-apparently infected, non-infected and vaccinated). We found that IgA, which has neutralizing activity, was produced after vaccination as well as after natural infection. It is suggested that local antibody induced by vaccination may contribute to protection against the mumps virus.

Antibodies, Viral↗

PubMed1992

IL-1 production as a regulator of G-CSF and IL-6 production in CSF-producing cell lines.

We previously demonstrated that colony stimulating factor (CSF)-producing cell lines co-produce interleukin-1 (IL-1) and IL-6 in addition to CSFs. In the present study, we examined the role of IL-1 production in three human tumour cell lines producing granulocyte (G)-CSF, IL-1 and IL-6. Addition of anti-human IL-1 alpha antiserum to the culture caused a 90-62% reduction of G-CSF and a 85-44% reduction of IL-6 production, respectively, as evaluated by enzyme immunoassay in all three cell lines. The decrease of G-CSF and IL-6 production by the anti-IL-1 alpha antiserum was also confirmed at the level of mRNA expression. The anti-IL-1 alpha antiserum did not affect the growth of these cell lines. Excess recombinant IL-1 alpha exogenously added to the culture enhanced G-CSF and IL-6 production in all three cell lines. However, IL-1 alpha had little effect on the growth of these three cell lines. Neither anti-IL-6 nor anti-G-CSF antibodies affected the production of the other cytokines. These results indicate that IL-1 alpha regulates G-CSF and IL-6 production in these tumour cell lines, and suggest that the IL-1 production plays an important role in CSF-producing tumours.

Cell Division↗

PubMed1992

Transport of 1,5-anhydro-D-glucitol into human polymorphonuclear leukocytes.

1,5-Anhydro-D-glucitol (AG) is one of the main polyols and its structure resembles glucose. It has been proposed that decreased serum AG concentrations in diabetic patients are a novel indicator of diabetic metabolic derangement. However, the pathway of AG metabolism still remains to be clarified. In this study we investigated the transport of AG into human polymorphonuclear leukocytes (PMNLs) isolated from healthy volunteers and found that 0.1 mM 3-O-methy-D-glucose (3OMG) was equilibrated with a half saturation time of 10 s, while the uptake rate of AG was much slower. The concentration dependence of AG uptake revealed that the AG transport velocity reached a plateau, with a Km of about 50 mM and Vmax of about 25 nmol/min/10(7) cells. Transport of 14C-labeled 3OMG was inhibited by unlabeled D-glucose or AG in a dose-dependent manner. The mean inhibition constant (Ki) for D-glucose and for AG were 1.06 and 4.93 mM, respectively. Cytochalasin B (20 microM) inhibited 3OMG transport by 90% but AG transport by only 50%. S/V for 14C-labeled AG transport plotted against the concentration of unlabeled 3OMG showed a non-linear and biphasic pattern. These results suggest that AG influx into PMNLs is mediated not only by the cytochalasin B-sensitive glucose transport system but also via another facilitated transport system.

3-O-Methylglucose↗

PubMed1992

Ionized calcium levels in coronary sinus blood during coronary angiography: effects of four contrast media.

The changes in ionized calcium level in the coronary sinus during coronary angiography were compared for four contrast media (meglumine sodium diatrizoate, iohexol, iopamidol, and meglumine sodium ioxaglate) in 44 subjects. Blood samples were collected before and 5, 15, and 30 seconds after injection of contrast medium into the left coronary artery. The hematocrit and ionized calcium level of each specimen were measured. Meglumine sodium diatrizoate produced the largest changes in hematocrit and ionized calcium level. The time-concentration curve of the hematocrit was similar for all four contrast media, but diatrizoate and ioxaglate produced a prolonged decrease of ionized calcium. The cause of this is not clear, but the phenomenon may be related to differences of ionic status among the contrast media. With respect to maintenance of the ionized calcium level, nonionic low-osmolality contrast medium with added calcium may be preferable for coronary angiography.

Adult↗

PubMed1992

High-resolution CT of the temporal bone: a modified baseline.

High-resolution computed tomography (CT) of the temporal bone, particularly axial scanning on a baseline parallel to the orbitomeatal line, produces radiation exposure to the patient's lenses. The authors evaluated the radiation dose to the lens and the visualization of temporal bone structures with use of scanning along the orbitomeatal line and on a line parallel to the hard palate. Evaluation of visualization was performed by five radiologists, with high-resolution CT scans of 45 healthy patients, and the chi 2 test was performed for comparison. The change of the baseline from the orbitomeatal line to a line parallel to the hard palate decreased the radiation dose to the lens from 12.7 cGy to 0.274 cGy and improved visualization of the stapes superstructure and the tympanic portion of the facial nerve canal, although visualization of the incus body, incudostapedial joint, lateral semicircular canal, and oval window was of equal quality. Therefore, the authors recommend a new baseline parallel to the hard palate for use at high-resolution CT of the temporal bone.

Health Personnel↗

PubMed1992

Thunberginols C, D, and E, new antiallergic and antimicrobial dihydroisocoumarins, and thunberginol G 3'-O-glucoside and (-)-hydrangenol 4'-O-glucoside, new dihydroisocoumarin glycosides, from Hydrangeae Dulcis Folium.

New antiallergic and antimicrobial dihydroisocoumarins, thunberginols C, D, and E, were isolated from Hydrangeae Dulcis Folium, the fermented and dried leaves of Hydrangea macrophylla SERINGE var. thunbergii MAKINO, together with new dihydroisocoumarin glycosides, thunberginol G 3'-O-glucoside and (-)-hydrangenol 4'-O-glucoside. Their chemical structures have been determined on the basis of chemical and physicochemical evidence. Thunberginols C, D, E, G, and (-)-hydrangenol 4'-O-glucoside showed antiallergic activity in the in vitro bioassay using the Schults-Dale reaction in sensitized guinea pig bronchial muscle, and they also exhibited antimicrobial activity against oral bacteria.

Animals↗

PubMed1992

[Effect of AS-4370 on gastric motility in patients with diabetic autonomic neuropathy].

Delayed gastric emptying in diabetic patients occurs with progress of automatic neuropathy as one late complication. Delayed emptying is deeply correlated with poor glycemic control, due to imbalance between nutrients absorption and effect of exogenous insulin. AS-4370 is a newly developed prokinetic agent which has been reported to selectively activate motility of the upper gastrointestinal tract through enhancing acetylcholine release from nerve terminals within the enteric mural plexus. In this study, we evaluated the effect of AS-4370 on gastric motility in diabetic patients with autonomic neuropathy. Eight diabetic patients with autonomic neuropathy (3 males and 5 females) with mean age of 56 years old (range 29-66) participated to this study after giving written informed consent. Gastric motility was evaluated by gastric emptying and electrogastrography. Gastric emptying study was done using 99mTc-Tin colloid labeled omelet meal served with 2 slices of toast and 200 ml of milk. Electrogastrography was recorded from epigastric skin surface, for 30 minutes before and after meal each. AS-4370, 7.5 mg tid, was given for four weeks after basal recording of gastric motility studies. Following the 4-week treatment with AS-4370, gastric motility studies were repeated. For the motility studies after medication, drug was given 30 minutes before test meal. Gastric retention rate at 150 minutes in all patients were over 45% of upper limit of normal range in basal study with mean value of 69 +/- 5%, which decreased significantly to 52 +/- 5%, with AS-4370 treatment (p < 0.01). Gastric emptying speed, another parameter for gastric emptying also improved with medication.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Effects of diethofencarb on thyroid function and hepatic UDP-glucuronyltransferase activity in rats.

To examine the mechanism and toxicological significance of thyroidal tumor observed slightly in a long-term rat study with diethofencarb (isopropyl 3,4-diethoxycarbanilate), male Sprague-Dawley rats were fed diethofencarb in diets at concentrations of 0, 5,000 or 20,000 ppm for 3 months. Examinations mainly for thyroid functions including thyroid uptake of 125I, serum thyroid hormone and thyroid stimulating hormone (TSH) level, hepatic UDP-glucuronyltransferase (UDP-GT) activity and histopathological examination in thyroid were performed at week 13. Decreases of body weights and food consumptions were observed at and above 5,000 ppm. Under these conditions, decrease of serum free T4 and increase of serum TSH level were observed only at 20,000 ppm, concurrently with liver weight increase at and above 5,000 ppm and increase of hepatic UDP-GT activity at 20,000 ppm. However, no compound related effects were noted in thyroid weight, thyroid uptake of 125I and gross or histopathological examination in thyroid. These results indicate that the administration of diethofencarb leads to an increase in UDP-GT activity and acceleration of thyroid hormone excretion from the liver. The acceleration causes a decrease in serum free T4 level, triggering the feedback mechanism of the pituitary gland, promotion of TSH release and consequently an increase in serum TSH level. Thus, the slightly higher incidence of thyroid follicular cell tumors observed in the chronic and oncogenicity study with non-genotoxic diethofencarb is considered to be caused by these weak pituitary-thyroid hormonal imbalances. The toxicological significance in humans is extremely low according to the well established facts that the chronic TSH stimulating would not induce thyroid tumors in humans and humans may be less sensitive than rats in regard to the response to goitrogenic stimuli.

Animals↗

PubMed1992

Clinical application of a newly developed surveying system for designing and fabricating removable partial dentures.

In this paper, some problems in commercially available surveying systems were discussed, and a clinical technique for designing and fabricating clasps by using an improved 'Digital Surveyor' and a computer system were presented. This system has the advantages as follows: (1) morphological factors on abutment teeth could be measured and evaluated using the improved 'Digital Surveyor' and its accessories set, (2) clasps providing with proper mechanical properties according to various conditions in the mouth could be designed and fabricated precisely and easily. It became clear that conventional surveying methods involved empirical rules should be re-examined and replaced by the more rational surveying method like this system.

Computer-Aided Design↗

PubMed1992

Development of a mandibular tracking device with six degrees of freedom using optoelectronic system.

The purpose of this study was to develop a prototype handy mandibular tracking device with six degrees of freedom using the optoelectronic kinematic data acquisition system and to evaluate its accuracy. The system consisted of the light-weight sensor part mounted on the mandibular incisor portion and two 2-D PSD cameras positioned in front of the patient. On the sensor part, three light emitting diodes (LEDs) were attached in triangular form. Displacements of the sensor part were detected by two cameras, transformed into electric signals, and sampled by A/D converter in a desktop computer. Since the overall accuracy of this system was about 0.03 mm in the displacement and 0.06 degrees in the rotation angles, this system was proven to be capable for the wide range of clinical application.

Humans↗

PubMed1992

Three dimensional shape measurement system for residual ridges.

It is very important for design and construction of complete dentures to evaluate the condition of residual ridges of edentulous patients objectively and precisely. The authors have been developing a shape measurement system for residual ridges. In this study, the outline of the system is described and the accuracy of the system is evaluated. The system consists of a high precision laser displacement meter, a working table and its controller, and a personal computer. The working table, on which a plaster model is placed, can move until the end of the moving range at a speed of 0.7 mm/sec. The height of the plaster model was measured intermittently with a frequency of 7 points/sec. To determine the accuracy of this system, experimental plaster models, which simulated the simplified shape of residual ridge, were measured and analyzed. The measurement error was 2.5%, which seemed to be highly accurate. The accuracy of the measurement decreased with the darkness of the color of the plaster model.

Alveolar Bone Loss↗

PubMed1992

Effects of heat treatment on mechanical properties of base metal wrought wire clasps.

The purpose of this study is to determine the effects of heat treatment and soldering on the change of shape and mechanical properties of cobalt-chromium-nickel alloy wrought wire clasps. The change of distance between the tips of the clasp arm was measured and mechanical properties were examined using the bending test. The following results were obtained. 1) By heat treatment at 500-700 degrees C for 10 minutes, bending rigidity and deflection at the proportional limit of the clasp arm increased significantly (p < 0.01), while permanent deformation after the bending test decreased considerably (p < 0.01). Concerning the deformation of clasp arms by heating, the distance between clasp tips increased remarkably above 500 degrees C (p < 0.01). 2) These mechanical properties of clasp arms were improved both by electric resistance soldering with silver solder and by heat treatment at 500 degrees C for 10 minutes after soldering. From these results, it was concluded that electric resistance soldering and adequate heat treatment were very effective to improve the mechanical properties of the clasp arm, especially to increase the deflection at the proportional limit and reduce the permanent deformation.

Chemical Phenomena↗

PubMed1992

Influence of dimensional factors and heat treatment on permanent deformation of wrought wire clasps.

The purpose of this study is to examine the fatigue profiles of wrought wire clasps during the clinical use. Cobalt-chromium-nickel alloy wires were bent into circular beams, which dimensions and fabrication methods were similar to the clinical cases. Deflections of 0.5 mm in a normal direction were applied 10,000 times to the tips of clasp arm and permanent deformations were measured. The following results were obtained. 1) The clasp arms with larger cross sectional diameter, shorter length and smaller radius of curvature showed larger amounts of permanent deformation. 2) The amounts of permanent deformation of the clasp arm remarkably decreased by electric resistance soldering and decreased further more by heat treatment at 500 degrees C for 10 minutes after soldering regardless of the number of deflection. From the results of this study, it was concluded that dimensional factors and heat treatment influenced the permanent deformation of the wrought wire clasps remarkably. Therefore, considering these factors, wrought wire clasps could be designed to reduce permanent deformation.

Chemical Phenomena↗