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Biomedical subjects

T Miyake

Publications and source records attributed to T Miyake.

At least 253 records · Page 14Linked to original sources
PubMed1989

The blood vascular architecture of the rat thyroid gland: a scanning electron microscope study of corrosion casts.

The blood vascular bed of the rat thyroid gland was reproduced by injection of a methacrylate casting medium and observed with a scanning electron microscope. The rat thyroid gland received the superior and inferior thyroid arteries and emitted the superior and inferior thyroid veins. Anastomosis between the interlobular arteries or between the interlobular veins was frequently observed in the thyroid gland. The arteriovenous anastomosis was rarely observed between the terminal branches of the lobular arteries and veins. The thyroid blood vascular bed was divided into lobular units which consisted of basket-like capillary networks surrounding the thyroid follicles; a small lobular unit consisted of a few networks, whereas a large one of fifty or more networks. Sizes and forms of the networks varied widely in each case. However, the networks in the superficial layers of the lateral parts of the thyroid gland were typically most developed. Regardless of its size and form, each network always received a proper efferent vessel continuous with the lobular vein, though it was sometimes provided with an accessory afferent or efferent vessel. Only occasionally were the adjacent networks fused with each other or connected by transfollicular capillaries. Thus, the present data suggest that each follicular capillary network is a fairly independent functional-unit in the thyroid microcirculation. The capillaries of the network were sinusoidal in nature and sometimes protruded fine projections which indicated the neogenesis of capillaries. The blood vascular bed of the newborn rat thyroid gland was not always differentiated into basket-like capillary networks.

Animals↗
PubMed1989

Effect of diethyldithiocarbamate on gastric and duodenal mucosal blood flow and vascular permeability in rats.

Diethyldithiocarbamate (DDC), an inhibitor of superoxide dismutase, produced ulceration in the proximal duodenum of rats, and erosions or ulcers in the stomach. DDC given s. c. at 1.5 g/kg increased duodenal and gastric vascular permeability, and reduced blood flow. The decrease in gastric blood flow caused by DDC was attenuated by pretreatment with superoxide dismutase, and significantly inhibited by a xanthine oxidase inhibitor, allopurinol. It is suggested that the superoxide and other radicals damage the mucosal vasculature, and play a role in the pathogenesis of gastric and duodenal mucosal lesions.

Animals↗
PubMed1989

Effect of plasmin inhibitors on gastric mucosal permeability in rats.

We examined the protective effect of plasmin inhibitors on gastric mucosal vascular permeability in rats. Tranexamic acid and aminocaproic acid significantly inhibited the increase in vascular permeability and macroscopic gastric mucosal lesions induced by 50% ethanol and 1% ammonia. The protective effect afforded by plasmin inhibitors was not affected by pretreatment with indomethacin. Our results show that plasmin inhibitors inhibit the increase in gastric vascular permeability and suggest that plasmin may play an important role in the pathogenesis of gastric mucosal damage.

Aminocaproates↗
PubMed1989

[Study on the finishing line of the metal framework in terms of modal analysis].

The finishing line on a metal framework strengthens the mechanized coupling between the metal and the resin. However, due to extreme variations in metal thickness on the finishing line section, stress tends to concentrate in certain areas during function, making the finishing line an area with frequent denture breakage in a clinical setting. The author used modal analysis to clarify the manner in which stress concentrates on the finishing line. The activity observed was them used to determine the influence on the activity of the finishing line from factors such as differences in the finishing line angle, differences in the major connector and differences in the skeleton configuration. The following results were obtained. 1. Regarding the resonance frequency of the test materials, modes 6-7 were detected. 2. Displacement in the periphery of the finishing line and for the major connector in each mode was extremely small compared to the amount of downward pressure on the mucose and the labio-lingual displacement of natural teeth. 3. The activity of the test materials between 200Hz and 300Hz was the rigid body mode for the entire test material using as a fulcrum the rest on the side where vibration was applied. There was resonance detected in the test materials between 1 kHz and 6 kHz. 4. It is believed that there is less concentration of stress on a palatal bar when the angle of the finishing line is an obtuse angle. 5. It was difficult to determine any effect on activity due to the difference in the angle of the finishing line on a palatal bar, lingual bar and lingual plate. 6. The skeleton configuration was more bended the lattice type than the ladder type.

Dental Stress Analysis↗
PubMed1989

[Evaluation of the laser-Doppler velocimetry method in the measurement of gastric blood flow in rats--spatial resolution].

In this paper, gastric blood flow in rats was measured with the laser-Doppler velocimetry method (the LDV method) to study about the tissue locus where its flow signal arises (spatial resolution). In the measurement throughout some 1 mm thickness of another nonperfused gastric wall interposed between the laser probe and gastric mucosal surface, its laser flow signal was 17% of the flow signal in the usual measurement. In the blood flow measurement with the LDV prove on the mucosal and the serosal surface of gastric wall, the laser flow signal on the mucosal surface was higher (p less than 0.05) than that on the serosal surface. These results suggested that the laser flow signal mainly arose from the tissue right under the laser probe, reflecting the total gastric blood flow of the gastric wall. In the regional blood flow measurement at corpus and antrum, the ratio between antral and corpus flow signals by the LDV method was similar to that between gastric mucosal blood flows at both sites by the hydrogen gas clearance technique. In the blood flow measurement after the intravenous infusion of each pentagastrin, isoproterenol, and vasopressin, flow signal of the LDV method could detect the each effect of these drugs on gastric mucosal blood flow as well as well as the hydrogen gas clearance technique. These results showed that the laser flow signal and gastric mucosal blood flow were mutually correlated.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[A successful arterial switch operation for the transportation of the great arteries with posterior aorta--with special reference to its anatomical features and possibility of the indication of the Jatene procedure].

A five months old infant with the transposition of the great arteries with posterior aorta undergoing arterial switch operation is reported. A pre-operative diagnosis of the transposition of the great arteries with posterior aorta, subarterial ventricular septal defect, anterior pulmonary artery, bilateral conus and fibrous continuity between aortic and mitral valve was made. This diagnosis was confirmed by the open heart surgery. The ventricular septal defect was subaortic from the transected aortic aspect, and the infundibular and trabecular septum was aligned. For these reasons, this subarterial ventricular septal defect was easily closed transaortically. The right coronary artery arose from the left sinus and the left coronary artery from the posterior sinus, so the coronary arterial pattern of this patient was a Shaher type 9. And in addition, another small ostium located in the left sinus gave rise to an additional small branch. Translocation of the coronary arteries was performed. The new pulmonary trunk was reconstructed to the right pulmonary artery so as not to compress the coronary artery and distort the great arteries. This patient was restudied three months after the repair. The right to left ventricular systolic pressure ratio was 0.42 and no pressure gradient was present between the right ventricle and the right pulmonary artery. But a moderate aortic regurgitation was detected. This was caused by deformity of the aortic sinus of valsalva. Only 28 patients with the transposition of the great arteries with posterior aorta were reported in the literature, but there were no reports on the successful surgical treatment for its rare anomaly, to our knowledge.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta↗
PubMed1989

[Effect of body position on gastric emptying of solid food--a study using a sulfamethizole capsule food method].

We studied the effect of body position on gastric emptying of solid food using a sulfamethizole capsule food method developed by us. Gastric emptying was significantly delayed in a supine position than in a sitting position kept for 120 minutes after ingestion of test food. These findings were observed in all of the young, middle and old aged groups. A longer sitting position after ingestion was associated with faster gastric emptying. Gastric emptying was significantly delayed in the old aged group than in the young aged group in both sitting and supine positions. Our results indicate that a postprandial sitting position is desirable for gastric digestion and emptying of solid food, especially in the old aged subjects.

Adult↗
PubMed1989

[Influence of theophylline and corticosteroid preparations on serum PAF acetylhydrolase activity in asthmatic children].

In our previous papers, we reported that serum PAF acetylhydrolase (PAF AH) activity in severely asthmatic children was lower than that in healthy or mildly asthmatic children, and that this enzymatic activity might be one of the factors that induce more severe respiratory symptoms in asthmatic children. In this study, we investigated the influence on PAF AH activity of theophylline and corticosteroid preparations, which are frequently used for the treatment of patients with bronchial asthma. Serum PAF AH activity and theophylline concentration were measured before and 3,4,6, 12 h after administration of a sustained-release theophylline preparation to 8 asthmatic children. Although the theophylline concentration was increased significantly at 3, 4 and 6 h after administration, PAF AH activity was unchanged, and there was no correlation between the two parameters. We then measured PAF AH activity in 6 asthmatic children before and 5 and 48 h after intravenous injection of 100 mg hydrocortisone succinate, and found no change in enzymatic activity. Furthermore, PAF AH activity in two severely asthmatic patients, who were being given low-dose corticosteroid on alternate days, was measured at regular intervals for 10 months in one case and 5 months in the other. The PAF AH activity showed no significant change in this period. These results show that PAF AH in asthmatic children is very stable, and is not affected by either theophylline or corticosteroid preparations.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed1989

[Effect of press stimulation applied to back skin on gastric emptying and serum gastrin response to solid food].

We studied the effect of press stimulation applied to the back skin on gastric emptying and serum gastrin response to solid food in healthy subjects. Although gastric emptying and serum gastrin response were significantly suppressed by press stimulation of T6-9 dermatomes corresponding to the spinal levels which sympathetic outflow to the stomach arise, they were not affected by press stimulation of T10-L1 dermatomes. Plasma levels of ACTH, epinephrine and norepinephrine, which usually increase by stresses acting on the brain, did not change by press stimulation of T6-10 dermatomes. These results suggest that press stimulation applied to the back skin of T6-9 dermatomes suppress gastric emptying and gastrin response to solid food mainly through the spinal cord.

Adult↗
PubMed1989

Zeta potential of oral bacteria (Streptococci).

This study was carried out to examine whether oral bacteria can be treated electrochemically in the same manner as colloid particles. The zeta potentials for 13 Streptococcus strains incubated in trypticase soy broth (TSBY) and heart infusion broth (HIB) were determined in 1/30 M phosphate buffer solution of pH 7.0 by standard microelectrophoresis. The zeta potentials for the Streptococci showed a wide range of values from -28.7 mV to -2.1 mV in TSBY and from -28.5 mV +2.0 mV in HIB. The zeta potential was useful in determining the potential structure of the bacterial cell as living colloid, especially Streptococcus.

Analysis of Variance↗
PubMed1989

Increased remineralization of subsurface enamel lesions with molybdenum treatment.

The present study was conducted to determine the effect of high molybdenum (Mo) concentration on fluoride (F) uptake and remineralization of subsurface lesions utilizing acid cyclic methods in vitro. Bovine enamel with artificial subsurface lesions were treated with test solutions containing 1,000 ppm F (NaF) with and without 1,000 ppm Mo at pH 7.0. F uptake was analyzed using a microdrilling technique and remineralization was evaluated by polarized light microscopy. The results indicate that addition of 1,000 ppm Mo in a 1,000 ppm F solution modestly increases F uptake and promotes remineralization of subsurface lesions compared with 1,000 ppm F alone. These findings suggest that a high level of Mo may enhance the remineralizing activity of F in subsurface bovine enamel lesions in vitro.

Animals↗
PubMed1989

[Quantitative assessment of pulmonary regurgitation by two-dimensional Doppler color flow imaging: postoperative evaluation of patients with tetralogy of Fallot].

Pulmonary regurgitation (PR) is a serious event following surgical repair for tetralogy of Fallot. For quantitative assessments of PR using noninvasive methods, we performed Doppler color flow imaging in 38 children, whose ages ranged from three to 15 years. All images were obtained from one to 10 years after surgery. The right ventricle and pulmonary valve were demonstrated in the parasternal short-axis view. The images of PR flow were in red and were frozen when the area of a signal was maximum (early to mid diastole). The PR distance index (PRDI), which is the maximum PR flow distance divided by square root of the body surface area, was measured. The PR area index (the maximum PR flow area/body surface area) (PRAI) was also calculated using a track ball. Cardiac catheterization was performed for 12 patients without residual L-R shunts or any apparent tricuspid regurgitation. PR was graded (0 = absent, 1 = trivial, 2 = mild, 3 = moderate, 4 = severe) according to the projection of contrast medium in the right ventricle as seen on the main pulmonary arteriogram. The size of the right ventricle was expressed as the right ventricular end-diastolic volume (RVEDV; % of normal), as determined from the cineangiogram, and the tricuspid valve annulus diameter (TVD; % of normal) from a four-chamber view of the two-dimensional echocardiogram. There were significant differences between the PRDI and the PRAI of five patients with PR of grades 1-2 and those of seven patients with PR of grade 3-4 (p less than 0.01, p less than 0.01, respectively). There was significant correlation between the % RVEDV and the % TVD observed (r = 0.82, p less than 0.01). Significant negative correlations were observed between the PRDI and right ventricular ejection fraction (RVEF), and the PRAI and RVEF (r = -0.68, p less than 0.02; r = -0.82, p less than 0.01, respectively). RVEF was below normal in all seven patients (100%) with PR of grade 3 or more and in one of five patients (20%) with PR of grade 2 or less. The PRDI of 2.5 or more, or the PRAI of 4.0 or more was equivalent to a PR of grade 3 or more and was a reliable index of significant PR.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1989

Autoimmune abnormalities in a murine model of accelerated senescence.

Immunopathological abnormalities in senescence-accelerated mice (SAM) were studied by comparison of senescence-prone (SAM-P/1) and senescence-resistant (SAM-R/1) mice. Sera from SAM-P/1 mice contained a number of autoantibodies, including natural thymocytotoxic autoantibody (NTA), anti-nuclear antibodies (ANA) and IgG anti-single-stranded and anti-double-stranded (ss and ds) DNA antibodies. Furthermore, an earlier increase in serum IgG2 levels and an earlier appearance of IgG circulating immune-complexes (CIC) associated with low C3 levels, were observed in SAM-P/1 mice. These serological findings were distinctive features in SAM-P/1 mice, which could almost discriminate these mice from SAM-R/1 mice. In addition, age-associated glomerular mesangial and capillary lesions with granular IgG and C3 deposition were frequently observed in SAM-P/1 mice, whereas SAM-R/1 mice even at 10 months of age showed only mild mesangial lesions. These findings suggest that autoimmune abnormalities may contribute to the accelerated senescence in these mice.

Aging↗
PubMed1989

[Measurement of antibodies to human T-lymphotropic virus type-1 (HTLV-1) in cerebro-spinal fluid in patients infected HTLV-1 by blood transfusion].

Although determination of the presence of antibodies to HTLV-1 in cerebro-spinal fluid (CSF) is very important for the diagnosis of HTLV-1-associated myelopathy (HAM), these antibodies in CSF have not yet been completely investigated so far in patients without overt HAM. We examined antibodies to HTLV-1 in CSF of leukemia patients who were infected with this virus via blood transfusion. All of 5 patients showed positive antibody titer, one of 5 patients was a patient with overt HAM. According to Western-blotting analysis in CSF, IgG p-19, 24 and 28 antibodies were positive in 4 patients without overt HAM, but IgM antibody was negative. In contrast, IgG antibodies as well as IgM p-24 antibody were positive in patients with overt HAM. These results suggest that further studies on antibodies to HTLV-1, especially on IgM antibody, in CSF of HTLV-1 infected patients with or without overt HAM may be helpful to better understanding of the mechanism on onset of HAM following blood transfusion.

Adult↗
PubMed1989

[Clinical studies of long-term administration of OK-432 in patients with gynecologic cancer].

The clinical value of OK-432 treatments, was evaluated in 215 patients with various types of gynecologic cancer. Five KE OK-432 was administrated by intramuscular injection every other day for up to 5 years, unless severe side-effects were observed. The 5-year survival rate was determined in 51 patients in the OK-432 group and 93 patients in the control group. The survival rate in the OK-432 group was significantly higher in the cervical cancer patients in stages III and IV than in the control group, at from 20 to 29 months and from 37 to 42 months. These results indicated that long period administration of OK-432 might improve the survival rate in patients with gynecologic cancer, especially in those with advanced cervical cancer.

Adult↗
PubMed1989

[A new device for the gastric emptying test--a sulfamethizole capsule food method].

We have developed a simple but reliable method for assessing gastric emptying, a sulfamethizole capsule food method. The capsule food contains egg albumin and sulfamethizole. In saline or hydrochloride solution only a small amount of sulfamethizole, in sodium bicarbonate solution, however, a large amount of the drug was released from the capsule food. In this method, sulfamethizole concentrations in blood were measured in subjects after ingestion of 15 pieces of capsule food containing 1.0 g of sulfamethizole, and area under the curve of the blood concentrations was calculated as an index of gastric emptying. Gastric emptying of capsule food had a lag phase of 15 minutes, which was already reported in gastric emptying of radioisotope labeled solid food. Bread combined with the capsule food caused a delay in gastric emptying and a larger volume of the bread was associated with a longer gastric emptying time. In conclusion, our sulfamethizole capsule food method is useful in clinical practice to assess gastric emptying of solid food.

Gastric Emptying↗
PubMed1989

Lectin histochemistry in ulcerative colitis and Crohn's disease.

The glycoconjugate composition of intestinal goblet cell mucin was characterized according to the anatomical distribution of lectin-binding sites in surgically resected intestinal tissues and mucosal biopsy specimens obtained from 38 control subjects, and from 32 patients with the active phase of ulcerative colitis, and 12 with Crohn's disease. Immunoperoxidase labeling studies found that in control tissues binding by Soybean Agglutinin (SBA), Dolichos Biflorus Agglutinin (DBA), Wheatgerm Agglutinin (WGA), and Ricinus Communis Agglutinin-120 (RCA-120) was consistently higher than that of Peanut Agglutinin (PNA), Ulex Europaeus Agglutinin-1 (UEA-1), Concanavalin A (ConA) and Helix Pomatia Agglutinin (HPA). Tissues from ulcerative colitis and Crohn's disease patients, showed increases in DBA and SBA binding, a reduction in HPA binding, and changes in the distribution of PNA, UEA-1, RCA-120, and HPA labeling sites. These results demonstrated that the expression of lectin-binding sites on human intestinal goblet mucin was specifically altered in ulcerative colitis and Crohn's disease, thus possibly providing another approach to the assessment of neoplastic risk on these diseases.

Adolescent↗