Biomedical subjects

S Miyauchi

Publications and source records attributed to S Miyauchi.

At least 127 records · Page 7Linked to original sources

PubMed1990

Effect of various organic anions on the plasma disappearance of 1-anilino-8-naphthalene sulfonate.

The effects of various organic anions on the hepatic transport of an anionic fluorescent dye, 1-anilino-8-naphthalene sulfonate (ANS) were investigated by measuring the plasma disappearance-time profiles in rats. Ten min after the i.v. administration of ANS (3 mumol/kg), various organic anions (60 mumol/kg) were injected in a bolus. Sulfobromophthalein (BSP), bromophenol blue (BPB) and rose bengal (RB) induced a transient increase in the plasma concentration of ANS (the so-called 'counter-transport' phenomena). The effect of rose bengal was somewhat different. After the administration of rose bengal, the plasma concentration of ANS decreased rapidly followed by a gradual increase. On the other hand, after the administration of bilirubin and taurocholate, the transient increases in plasma ANS concentrations were minimal. No effect was observed after the administration of phenolsulfophthalein (PSP) or oleate. The effects of these organic anions on the binding of ANS to rat liver cytosols were examined by equilibrium dialysis. Sulfobromophthalein, bromophenol blue and rose bengal, which yielded an in vivo 'counter-transport' phenomena, markedly inhibited ANS binding to cytosolic proteins. On the other hand, the other organic anions examined had very small, if any, inhibitory effect. The ANS binders in the cytosol were then identified by gel filtration. ANS bound mainly to X and Y (ligandin) fractions in the cytosol. Sulfobromophthalein, which is one of the organic anions exhibiting the in vivo 'counter-transport' phenomenon, remarkably inhibited ANS binding to ligandin fraction. It was thus suggested that the in vivo 'counter-transport' phenomena may be also explained by the enhancement of back diffusion due to the displacement of intracellular binding. In conclusion, one should be more cautious in interpreting data obtained from so-called in vivo 'counter-transport' experiments.

Anilino Naphthalenesulfonates↗

PubMed1990

The effect of sodium hyaluronate on the migration of rabbit corneal epithelium. I. An in vitro study.

The effect of sodium hyaluronate (Na-HA) on the migration of corneal epithelium was investigated in vitro using corneo-scleral sections of rabbits. The effect on migration was evaluated by the length of migrating epithelium on the cut surface of corneal stroma after incubation in media containing Na-HA of various molecular weights or concentrations. The medium concentration of Na-HA was 400 micrograms/ml, and the molecular weights were 0.4 x 10(4), 2 x 10(4), 10 x 10(4), 68 x 10(4), 102 x 10(4) and 216 x 10(4). Regarding Na-HA with a molecular weight of 102 x 10(4); media containing Na-HA at concentrations of 50, 100, 200, 400, 800, 2000 and 4000 micrograms/ml were also investigated. When the concentration of Na-HA was 400 micrograms/ml, Na-HA with molecular weights of over 68 x 10(4) accelerated significantly the epithelial migration. Regarding Na-HA with a molecular weight of 102 x 10(4), acceleration was observed at concentrations of 200, 400 and 800 micrograms/ml. Furthermore, the concentration of fibronectin (FN) in medium containing the effective Na-HA was significantly lower than that in the control medium after the incubation. These results suggest a possibility that the accelerative effect of Na-HA depends on the reduction of FN release from the cornea or the facilitation of FN deposition on the cornea.

Animals↗

PubMed1990

The innermost cell layer of the outer root sheath is positive with Ki-67.

The expression of a cell proliferation-associated human nuclear antigen was immunohistochemically studied in human anagen hair and hair follicles using the monoclonal antibody Ki-67. The reaction of Ki-67 in mature anagen hair follicles was observed in the hair matrix cells and outer root sheath (ORS) cells. Nuclear staining was seen in a small number of matrix cells and in some ORS cells; this finding corresponded to the thymidine or bromodeoxyuridine labeling studies previously reported. In addition, there were two different patterns of cytoplasmic staining in the ORS: strong staining of the innermost cells (IMC) and weaker staining of the other ORS cells in the isthmus. Ki-67 reactivity of the IMC layer was observed at each stage of anagen and was regularly seen from the upper bulb to the isthmus. Ki-67 is a commercially available antibody that detects cycling cells. However, the IMCs in anagen hair follicles showed cytoplasmic labeling by Ki-67 from the matrix cells in the upper bulb to the distal portion of the isthmus.

Adolescent↗

PubMed1990

[Evaluation of mica crystal glass ceramic crown marginal fitness].

The purpose of this study is to investigate the influence of three marginal shape of abutment teeth (Flat, Moderate and Steep) on the fitness of castable glass ceramics (DICOR) crown clinically. The following results were obtained: 1. The change of width of three marginal shapes showed the same tendency on each firing procedure. 2. The vertical change of three marginal shapes showed the most constant on Flat and decreased on Steep. 3. On the marginal edge, the Labiopalatal gaps were larger than Mesiodistal gaps. 4. On Labiopalatal section, the gaps of Steep were larger than those of Flat and Moderate especially as cast. 5. The gaps Flat were almost same on Labial, Palatal, Mesial and Distal parts.

Aluminum Silicates↗

PubMed1990

The influence of materials difference on stress distribution and bone remodeling around alumina and titanium dental implants.

The long-term complications of dental implants are associated with loosening of the implant-bone interface, due to bone resorption and subsequent connective tissue interposing at the implant-bone interface. Mechanical stresses, which are induced in the surrounding bone, play a key role in the interface bone remodeling. In the present study, it is investigated how local stress patterns are associated with local bone structure. For identical geometry alumina, and titanium implants, the stress patterns, determined in the finite element models with boundary conditions, are compared with the local bone structure found in animal experiments. The results indicate that there appears to be relationship between the stress patterns and the bone remodeling at the implant-bone interface independently on the materials properties in alumina and titanium.

Aluminum Oxide↗

PubMed1990

Treatment of anterior disk displacement without reduction by "disk recapturing bite plane".

Eight subjects with a diagnosis of anterior disk displacement without reduction were used for the evaluation of the efficacy of conservative treatment using Disk Recapturing Bite Plane. Examinations were performed before and after treatment. The post-treatment examination revealed that this bite plane improved the structural bone changes and condylar dislocations. In addition, the characteristic chewing patterns of anterior disk displacement without reduction were normalized. These results indicate that the disk recapturing bite plane is one of the effective treatments of anterior disk displacement without reduction.

Cartilage, Articular↗

PubMed1989

A measurement of regional portal blood flow with Xe-133 and balloon catheter in man.

This investigation was undertaken to measure regional portal blood flow of the liver. The measurement was performed by injecting 133Xe into the proper hepatic artery through a balloon catheter and then occluding the proper hepatic artery with an inflated balloon. Data were collected using a gamma camera, and washout curves were generated. They were analyzed by the initial slope method and Kety Schmidt equation. The average regional portal blood flows were: 59.31 +/- 13.04 ml/100 g per min, 58.71 +/- 14.14 ml/100 g per min and 37.12 +/- 10.11 ml/100 g per min in hospital controls (11), patients with chronic hepatitis (10) and those with liver cirrhosis (56), respectively. In the patients with cirrhosis, the regional portal blood flow was significantly reduced (P less than 0.01). The reproducibility of this method was satisfactory. The measurement of regional portal blood flow will be useful to evaluate underlying liver injuries and determine indications of a transcatheter arterial embolization of the liver.

Catheterization↗

PubMed1989

Alleviation of gallbladder complications by treatment of hepatic arterial embolization with caerulein.

Transcatheter arterial embolization (TAE) with the concurrent use of caerulein was assessed for the purpose of preventing gallbladder complications often seen after TAE of hepatic carcinoma. Ninety-six cases with primary hepatic carcinoma, who had undergone TAE in the right hepatic arterial region over the past 4 years, were divided into three groups: 22 cases for which embolization was possible on a selective basis by passing the catheter to the peripheral side beyond the bifurcated region of the cystic artery; 40 cases who had undergone TAE in which caerulein was not administered, from the central side of the bifurcated region of the cystic artery; and 34 cases given 20 micrograms caerulein 15-30 min before TAE. A comparison was made using the abdominal pain, pyrexia, rate of leukocytosis and the US findings of the gallbladder as the indices of the gallbladder complications. As a result, it became evident that it was possible to prevent or alleviate gallbladder complications if caerulein were administered before TAE in cases where the embolizing substances were infused in the right hepatic artery from the central side of the bifurcated region of the cystic artery. It was conclusively shown that the gallbladder blood flow decreases if the organ is contracted by caerulein, which in turn causes a decrease in the inflow of the embolizing substances whereby complications are alleviated.

Adult↗

PubMed1989

Analysis of unsaturated disaccharides from glycosaminoglycuronan by high-performance liquid chromatography.

A rapid and simple analytical method for unsaturated disaccharide isomers formed by enzymatic digestion from hyaluronic acid, chondroitin sulfate, dermatan sulfate, heparan sulfate, and heparin by high-performance liquid chromatography using an amine-bound silica column with a linear gradient of sodium dihydrogen phosphate was developed. The analyses were performed on isomers of two groups belonging to the chondroitin sulfate family and the heparin sulfate family. In both families, disaccharide isomers eluted in the order non-, mono-, di-, and trisulfated disaccharides by elevating salt concentrations. The method was applied to the analysis of constituent disaccharides of representative sulfated glycosaminoglycans, which proved that most constituents could be quantified separately. This method is advantageous in that enzymatic digests can be applied directly on a column without any pretreatment and good resolution of several disaccharides can be obtained by one chromatography.

Chondroitin↗

PubMed1989

Evaluations on the usefulness of viscous agents in anterior segment surgery. II. Effect on intraocular pressure and clearance from the anterior chamber.

Various viscous agents in anterior segment surgery were replaced with the aqueous humor of rabbit eyes. The effects of these agents on intraocular pressure (IOP) and their clearance from the anterior chamber were studied. Furthermore, the degradation of these agents in ocular and hepatic tissues was investigated. The IOP after the injection of a 1% solution of sodium hyaluronate with a molecular weight of 790 x 10(3) (Na-HA (790 x 10(3), 1%], fell to the normal level after 12 hours; however, after a 1% solution of sodium hyaluronate with a molecular weight of 2160 x 10(3) (Na-HA (2160 x 10(3), 1%], a 2% solution of methylcellulose with a molecular weight of 86 x 10(3) (MC (86 x 10(3), 2%] or a 30% solution of sodium chondroitin sulfate with a molecular weight of 30 x 10(3) (Na-Chs (30 x 10(3), 30%], the return of IOP to normal level required 24 hours. Six hours after the injection of MC (86 x 10(3), 2%), the IOP was significantly higher than those of other agents. Na-Chs (30 x 10(3), 30%) and Na-HA (790 x 10(3), 1%) were eliminated from the anterior chamber within 12 and 24 hours, respectively. Na-HA (2160 x 10(3), 1%) and MC (86 x 10(3), 2%) required 72 hours to be eliminated from the anterior chamber. The degradation of Na-HA was detected in extracts of the iris, corneo-scleral junction, and liver. The degradation of Na-Chs was also detected in the liver extract, but the degradation of MC was not detected. On the basis of these findings, and the results in our previous report with respect to the efficacy of the viscous agents, it is concluded that Na-HA is the best viscous agent to be used in anterior segment surgery.

Animals↗

PubMed1989

Mitotic activities of normal epidermal Langerhans cells.

We have previously reported a sequence of events which occurs during the recovery phase of the murine epidermal Langerhans cells (ELCs) after ultraviolet-B irradiation. We found that an ATPase-positive round cell divides, dendrites are gradually formed, and paired dendritic cells are eventually separated as the post-irradiation time elapses. We wondered if a series of events similar to this might occur in the normal murine epidermis without irradiation. In this study, we could identify exactly the same phases of the ELC mitotic cycle in normal mouse ear skin.

Adenosine Triphosphatases↗

PubMed1989

The conjugative metabolism of 4-methylumbelliferone and deconjugation to the parent drug examined by isolated perfused liver and in vitro liver homogenate of rats.

We examined the disposition of 4-methylumbelliferone (4-MU) and its conjugative metabolites, glucuronide (4-MUG) and sulfate (4-MUS), using a single-pass rat liver perfusion system. When 4-MU was delivered, the steady-state hepatic extraction ratio for 4-MU was very high (approximately 1.0) and its conjugative metabolites, 4-MUG and 4-MUS, appeared to a large extent in the effluent perfusate. The biliary excretion rate of the 4-MUG conjugated from 4-MU was 44% of the infusion rate at the steady-state, whereas those of 4-MU and 4-MUS were less than 1% of the infusion rate. When 4-MUG was delivered, the steady-state hepatic extraction ratio for 4-MUG was very low (less than 0.05) and the removal rate of 4-MUG from the perfusate was almost identical to the excretion rate of 4-MUG into the bile, while 4-MU and 4-MUS were slightly excreted into the bile (1% of the total biliary excretion rate), suggesting that a little deconjugation of 4-MUG to 4-MU occurred in the liver. Similarly, 4-MU and 4-MUS were not detectable in the effluent perfusate. The apparent extraction ratio (Eapp) for the intracellularly conjugated 4-MUG was approximately twenty times higher than that for the pre-conjugated 4-MUG. This discrepancy between the values of Eapp for the intracellularly conjugated and pre-conjugated 4-MUG might be attributed mainly to the diffusional barrier for the metabolite between the blood and hepatocytes, as suggested in the previous simulation (J. Pharmacokin, Biopharm., 15, 399 (1987].(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

[Relationship between condylar atrophy and tooth loss in stomatognathic dysfunction].

In our previous study, we concluded normal subjects did not present an abnormal morphology of condyle, while 30% of stomatognathic dysfunction patients revealed abnormality, and especially about 20% presented atrophy. In this study, we selected 146 patients with stomatognathic dysfunction and analysed patients with atrophy in condyle comparing patients without atrophy. We obtained following results. 1. 37 patients (25%) with dysfunction showed atrophy in condyle. Among them, 15 patients showed bilateral atrophy, and 22 showed unilaterally. 2. Among 22 patients with unilateral atrophy in condyle, 15 patients (68%) showed correspondence between symptomatic side and atrophy side. 3. Among 37 patients with atrophy in condyles, 30 patients (81%) showed organic changes in TMJ components. 4. Mean age of atrophy (+) group was significantly younger than that of atrophy (-) group. 5. No significant relationship was observed between the distinction of sex and atrophy existence in condyle. 6. Significant relationship was observed between loss of lower first molar and atrophy existence in condyle. Most of the patients of atrophy (+) group lost their lower first molars in growth period of TMJ components from mixed dentition through puberty and left them without restoration.

Atrophy↗

PubMed1989

[Chewing pattern in posterior crossbite. Classification of chewing pattern in the frontal plane].

Occlusion is one of the most important factors to affect chewing movement. In this study, chewing movements of subjects who have posterior crossbite were recorded to analyze the relationship between chewing pattern and crossbite occlusion. Chewing movements of 22 subjects of posterior crossbite and 5 normals were recorded with Sirognathograph Analysing System II. Subjects were to chew soft gum; on each specified side, both at the posterior crossbite region and at another resion of the side. On the other hand, normal subjects were to chew only on each side. Chewing patterns were classified into several specific ones examined with chisquare test concerning the relationship between chewing pattern and occlusion. From the results we obtained following conclusion. 1. Frequency of normal chewing pattern, posterior crossbite group is lower than normal group. 2. Among the posterior crossbite group, specific patterns are found with highly frequency such as 'Concave Type', 'Crossover I Type', 'Crossover II Type' and 'Reverse Type'. 3. By segmental chewing at the posterior crossbite region, 'Normal Type' and 'Concave Type' are lower and 'Crossover I Type', 'Crossover II Type' and 'Reverse Type' are higher in frequency in comparison with posterior crossbite side voluntary chewing. 4. By segmental chewing at the posterior crossbite resion, 'Normal Type' and 'Concave Type' are lower and 'Crossover I Type', 'Crossover II Type' and 'Reverse Type' are higher in frequency in comparison with segmental chewing at non-crossbite resion.

Humans↗

PubMed1989

Condylar movements during mastication.

To investigate the relationship between mastication and TMJ abnormalities, the incisal point and condylar movements during mastication were analysed in two normal subjects and six patients with stomatognathic dysfunction. The patients with stomatognathic dysfunction were two patients with unilateral anterior disk displacement with reduction, two with unilateral anterior disk displacement without reduction, and two with unilateral osteoarthritis. The incisal point movement was recorded using Sirognathograph Analysing System, and condylar movement was recorded with a pantograph. The movement path of the non-working condyle was shorter than that of the working condyle when patients with unilateral TMJ abnormalities used their non-abnormal side to chew, which resulted in deviation of the turning point (the point where the mouth changes from opening to closing) to the non-chewing side. Also, the convexity of the opening path was influenced by the condylar mobility of the abnormal side TMJ. Posterior dislocation of the condyle of the abnormal side TMJ resulted in a crossover chewing pattern of incisal point movement in the frontal or horizontal planes.

Adult↗

PubMed1989

Thy-1+ dendritic epidermal cells undergo mitosis in vivo.

Recently, morphologic evidence that epidermal Langerhans cells (ELC) undergo a mitotic cycle in normal mouse ear skin has been presented. In the present study, using immunohistochemical staining, we examined the mitotic activity of Thy-1-positive dendritic epidermal cells (Thy-1+DEC) in the normal murine epidermis. A small number of Thy-1+DEC showed round, cleaved, paired, and paired dendritic morphologies, which are identical to those occurring during ELC mitosis. We conclude that normal Thy-1+DEC undergo mitosis within the epidermis to maintain their population in the murine epidermis.

Animals↗

PubMed1988

Membrane-limited hepatic transport of the conjugative metabolites of 4-methylumbelliferone in rats.

The hepatic transports of 4-methylumbelliferone (4-MU) and its conjugative metabolites, the glucuronide (4-MUG) and sulfate (4-MUS), were investigated in rats with various methods. The extraction ratio (E) was estimated with the multiple indicator dilution (MID) method using isolated perfused rat liver. The values of E for 4-MUG and 4-MUS were much lower (less than 0.2) than that for the parent compound, 4-MU (0.89). In addition, we examined the simulation of the outflow curves of conjugates based on the "distributed" model in which we varied the permeability between the blood and hepatocytes. When the permeability was much smaller relative to the hepatic blood flow, the simulated curve was superimposed on the dilution curve. These results suggest that the influx permeabilities of these conjugates are so low that little extraction occurs during the passage through the liver. Measuring the unidirectional uptake of these conjugates into the liver with the in vitro centrifugal filtration method using isolated hepatocytes, we determined the influx permeabilities (PSinf(total] for the total ligands. The value of PSinf(total) determined with the in vitro method was extrapolated to that per gram of liver, assuming 1 g of liver has 1.3 X 10(8) cells. The values of PSinf(total) for 4-MU, 4-MUG, and 4-MUS were 4.8, 0.06, and 0.11 mL/min/g liver, respectively. Thus, the influx permeabilities for 4-MUG and 4-MUS were much smaller than the hepatic blood flow (1.6 mL/min/g liver), confirming the results of MID method.

Animals↗

PubMed1988

Malignant tumor cell lines produce interleukin-1-like factor.

Sixty-four malignant cell lines were examined for interleukin-1 (IL-1) activities in their conditioned medium using thymocyte and fibroblast proliferation assays. Sixteen cell lines showed high IL-1 activity. Comparison of these activities with human IL-1 showed similarity between some biological properties. However there was no correlation between cell origin and IL-1 activity. These results suggest the possibility that most malignant cells may produce an IL-1-like factor.

Epidermal Growth Factor↗