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Biomedical subjects

M Miyata

Publications and source records attributed to M Miyata.

At least 451 records · Page 25Linked to original sources
PubMed1990

[A pupillographical study on the presence of organochlorine pesticides in autonomic nerve disturbance].

It is well known that the effect of organophosphate pesticides on the autonomic nervous system is a cholinergic reaction. However no study has been done assessing the effect of organochlorine pesticides on the autonomic nervous system. We evaluated the autonomic nerve function using open-loop pupillography in 20 patients who had exposure to the organochlorine pesticides. Significant differences were seen in pupil area (p less than .006), velocity of both constriction and dilatation (p less than .001), and dilatation time (p less than .02), when compared with 18 normal subjects. Autonomic nerve disturbances were detected in eighteen of 20 patients (90%) by evaluating the pupillary light reflex in each patient. Sympathetic nerve inhibition i.e. sympatholytic pattern, was recognized in ten of 18 patients (55%). Four patients with sympatholytic pattern had a disturbance not only in the sympathetic nerve, but also parasympathetic nerve involvement suggesting pandysautonomia. The residue blood level of the organochlorine pesticides was examined in each patient. A high frequency of the DDE was recognized (85%). It was concluded that the toxicity of the organochlorine pesticide on the autonomic nerve appear as an inhibitory effect on pupil light reflex.

Adult↗
PubMed1990

[Thyroid cancer metastasis to the lumbar spine successfully treated by embolization and radioiodine. A case report].

A 82-year-old woman suffered from a metastatic lesion of follicular carcinoma of the thyroid to the fourth lumbar spine, which compressed the spinal nerves and caused lumbar pain and paresthesis of the lower limb. External irradiation, 5200 RAD, was carried out. Total thyroidectomy was done for the preparation of radioiodine(131I) therapy. Two weeks later, embolization of lumbar arteries was performed to prevent the progression of the spinal cord damage during a period waiting for 131I administration. The size of the lumbar lesion decreased, and lumbal pain and spinal cord symptoms disappeared. After administration of 131I, the metastatic lesion became further smaller.

Adenocarcinoma↗
PubMed1989

Different patterns of leakage of cytosolic and mitochondrial enzymes.

The mechanisms of leakage of intracellular enzymes, and especially the cytosolic and mitochondrial isozymes of aspartate aminotransferase (AST), in ischemic rat liver were studied. On recirculation of ischemic liver, cytosolic AST (cAST) promptly appeared in the blood. Release of cytosolic enzymes, including cAST and lactic dehydrogenase, resulted from disruption of blebs that protruded from parenchymal cells into the sinusoidal space. When these blebs were formed in ischemic liver, mitochondria still remained in core regions of the injured cells and were not found in the blebs. Consistent with this fact, mitochondrial AST (mAST) did not leak into the circulation from ischemic liver until most of the cAST had leaked out. This delayed leakage of mitochondrial enzymes was also consistent with the fact that the mitochondrial membranes maintained a diffusion barrier against matrix enzymes even after anoxia for 2 h, when their oxidative phosphorylation capacity had been lost. These results indicate that mitochondrial enzymes are liberated into the blood only after appreciable disintegration of the cells, probably necrosis, and that the cumulative activity of mAST in the blood should reflect the extent of necrosis in ischemic organs better than that of cAST.

Animals↗
PubMed1989

Cancer cell emboli in the pectoral lymphatics of patients with breast cancer.

In order to investigate the possibility of local recurrence in the pectoral muscles of patients who undergo modified radical mastectomies, the cancer cell involvement of the lymphatics associated with the pectoralis major muscle was studied in 39 patients who underwent a standard radical mastectomy for Stage I-III breast cancer. Cancer cell emboli were found in the transpectoral lymphatics of 2 patients (2/39 = 5.1 per cent) and in the pectoral fascial lymphatics of 6 patients (6/39 = 15.4 per cent). Two patients with fascial lymphatic cancer cell emboli were from a group of 14 patients with intramammary lymphatic tumor emboli of a low degree (ly 1). The other 6 patients with cancer cell emboli in either the pectoral fascia or the transpectoral lymphatics were from a group of 11 patients with intramammary lymphatic tumor emboli of a moderate degree (ly 2). There was a significant relationship between the intramammary and the pectoral lymphatic cancer cell emboli (Chi square test: (p less than 0.05). The results of this study therefore indicate that lymphatic cancer cell emboli in the pectoral fascia and muscle are an important risk factor for patients who undergo a modified radical mastectomy.

Adult↗
PubMed1989

Interaction of two heads of myosin with F-actin: binding of H-meromyosin with F-actin in the absence of nucleotide.

The bindings of S-1 and the two heads of HMM with pyrene-labeled F-actin were studied using the change in light-scattering intensity or that in the fluorescence intensity of the pyrenyl group. At low ionic strength (50 mM KCl), both S-1 and HMM became bound tightly with F-actin (Kd less than 0.1 microM) and both heads of HMM became bound to F-actin. The affinities of S-1 and HMM for F-actin decreased with increasing KCl concentration. In 1 M KCl, the Kd values of S-1 and HMM for F-actin were 11 and 0.58 microM, respectively. Thus, HMM was bound to F-actin 19 times more tightly than S-1. We compared the extent of binding of HMM to F-actin measured by a centrifugation method with that measured by the fluorescence change of pyrenyl-group, and found that even in 1 M KCl, HMM became bound to F-actin with a two-headed attachment. We measured the kinetics of binding and dissociation of acto-S-1 and acto-HMM from the time course of the change in light-scattering intensity after mixing S-1 or HMM with F-actin at 1 M KCl and that after mixing 1 M KCl with acto-S-1 or acto-HMM formed at low ionic strength.(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗
PubMed1989

Reaction intermediates formed by myofibrils during the ATPase reaction under relaxed conditions.

The species and amounts of intermediates formed by myosin in myofibrils during the ATPase reaction under relaxed conditions were examined. The amount of total nucleotides (ADP + ATP) bound to myofibrils, determined by a centrifugation method or a rapid filtration method, was 0.86 mol/mol myosin head. The amount of bound ADP, determined as the ADP remaining in the mixture after free ADP had been rapidly converted into ATP by an ATP-regenerating system, was found to be 0.67 mol/mol myosin head. We examined the time courses of free-Pi and total-Pi (TCA-Pi) formation after adding ATP to the myofibrils. The amount of Pi bound to myofibrils, calculated by subtracting the burst size of free Pi (0.23 mol/mol myosin head) from that of TCA-Pi (0.60 mol/mol myosin head), was found to be 0.37 mol/mol myosin head. The amount of tightly bound ATP determined by an ATP-quenching method was very low (0.03 mol/mol myosin head). If there is no myosin-phosphate complex, then the amounts of the myosin-phosphate-ADP complex, MADPP, and the tightly bound myosin-ATP complex, M*ATP, are 0.37 and 0.03 mol/mol myosin head, respectively, whereas the amounts of myosin-ADP and loosely bound myosin-ATP complexes are 0.30 and 0.16 mol/mol myosin head, respectively. Thus, half of the myosin heads forms MADPP or M*ATP, and the equilibrium between MADPP and M*ATP shifts to the MADPP side. These results agree with those obtained for myosin in solution (Inoue, A., Takenaka, H., Arata, T., & Tonomura, Y. (1979) Adv. Biophys. 13, 1-194). Therefore, in relaxed myofibrils the active site of myosin does not interact with actin.

Adenosine Diphosphate↗
PubMed1989

Elevated serum secretory IgA in patients with IgA nephropathy.

Serum secretory IgA was measured to elucidate the significance of secretory IgA in patients with IgA nephropathy. The levels of serum secretory IgA and IgA were, respectively, 6.8 +/- 3.5 micrograms/ml and 231.0 +/- 69.2 mg/dl in the controls and 11.8 +/- 3.2 micrograms/ml and 385.3 +/- 78.7 mg/dl in the patients. The levels of serum secretory IgA and IgA in the patients were significantly higher than those in controls (p less than 0.01). Elevated serum secretory IgA may reflect the excessive state of the IgA-secreting system in IgA nephropathy patients.

Adolescent↗
PubMed1989

IgG rheumatoid factor in human and rabbit transplantation sera.

Sera of human recipients of kidney allografts and rabbit recipients of skin allografts were tested by means of enzyme immunoassays (EIA) for IgG rheumatoid factor (RF) combining with human IgG (RF-H) or rabbit IgG (RF-R). In humans, the mean OD value in EIA for RF-H was significantly higher in 185 sera of allograft recipients than in 46 pretransplantation sera and 100 sera of normal subjects. Furthermore, the mean OD in patients who rejected their grafts was higher than in patients with satisfactory graft function. Interestingly, there was no difference in OD values for RF-R between sera of graft recipients and sera of normal subjects. Of 52 rabbit recipients of skin allografts, 24 were positive for both RF-R and RF-H, 4 were positive only for RF-R, another 4 only for RF-H, and 20 were negative for both. Renal allografts originating from the previous donors of skin grafts resulted, in most instances, in a significant decrease in the strength of the reaction for both RF-R and RF-H. The possible role of graft rejection in stimulation of RF formation as well as the possible role of RF in graft rejection should be considered.

Animals↗
PubMed1989

Hepatic level of mRNA in relation to polymorphism and strain difference in expression of cytochrome P-450g.

Hepatic level of mRNA for P-450g was determined in male and female rats of Sprague-Dawley, ACI and Fischer strains using a specific oligonucleotide probe. The mRNA level in female Sprague-Dawley and Fischer rats was undetectable in accordance with a very low or undetectable level of P-450g protein. The mRNA was detected in all male ACI rats, in which high levels of P-450g protein were detected. In Fischer male rats, mRNA for P-450g was clearly detected in the liver, but P-450g protein was not detected. Moreover, the mRNA was detected in the liver of all male Sprague-Dawley rats, irrespective of the expressed level or absence of P-450g protein. As a most plausible explanation of the observed discordance in the levels of P-450g mRNA and protein, translation of unstable protein for microheterogeneous P-450g is discussed.

Animals↗
PubMed1989

[Central neurocytoma. Case report].

A 24-year-old female was hospitalized for progressive headache and nausea. Computed tomography showed a mass lesion in the left lateral ventricle near the foramen of Monro. On light microscopy, this tumor morphologically resembled an oligodendroglioma. However, ultrastructural examination disclosed synapses and neuronal differentiation. Review of the literature revealed 21 cases of intraventricular neuronal tumors in adults that were diagnosed as central neurocytoma or differentiated neuroblastoma. Fourteen of the 21 patients were males and seven were females. Their ages ranged from 16 to 52 years and averaged 30.7 years. All of the tumors were located near the foramen of Monro and the clinical symptoms were primarily headache and nausea. The outcome was generally good. Surgical removal was the most effective treatment, whereas the effect of radiation therapy was unclear. The diagnosis requires demonstration of neuronal differentiation. Generally, the diagnosis is neurocytoma if the neuronal tissue is mature, with complete synapses, and neuroblastoma if it is immature. However, the criteria for differentiation between these two tumors are still controversial.

Adult↗
PubMed1989

[A questionnaire about the dental treatment for visiting patients at welfare center for the aged people].

A questionnaire about the dental treatment for visiting patients at Welfare center for the aged people. Nowadays, 11 percent of the population is over 65 in Japan. According to the Minister of Health and Welfare's Population Projection for Japan, it will grow to 20% at the beginning of the 21st century. Problems concerning old people will become some of Japan's biggest challenges. In that situations, the dental treatments for visiting aged patients will become more important. Then, authors sent out a questionnaire about it on aged people who have no need of anyone's assistance in their home lives. And we examined concrete countermeasures and problems about the dental treatments for visiting patients. The findings were as follows: 1. Even the aged people who have no need of anyone's assistance in their home lives, they hope much carrying out the dental treatments for visiting them. 2. The dental treatments for visiting aged patients have some problems. But it will become one of the most important way to supply their demand for dental treatments, in spite of their latent requirements, a lot of old people give up to undergo dental treatments.

Aged↗
PubMed1989

[A combined treatment of carcinoma of the maxillary sinus--treatment method for T4 cases].

Between 1974 and 1986, 54 cases of squamous cell carcinoma of the maxillary sinus were treated combining surgery, radiotherapy and regional chemotherapy simultaneously. Using UICC (1987) system, these 54 cases were classified into one T1, four T2, thirty-three T3 and sixteen T4. The combined therapy consisted of 1) reduction operation followed by daily cleaning of the necrotic tumor mass; 2) external irradiation with less than 30Gy; 3) intra-arterial infusion of 5-fluorouracil (5-FU) and broxuridine (BUdR); and 4) final tumor resection under general anesthesia. As several modifications were made for the treatment procedure in 1979, the 54 cases were divided into two groups: Group A with 29 cases, which were treated before 1979 and Group B with 25 cases, which were treated after 1979. In this paper, the operative procedure, which we use for T4 cases is described. The first operation is performed after radiotherapy with about 10Gy and in this operation only the necrotic portion of the tumor mass is removed. The maxillary cavity is opened through the sublabial incision. This window is kept open and daily cleaning of the necrotic tumor mass is continued through the window. Three weeks after the simultaneous administration of radiation with 20Gy and 5 intra-arterial infusions of 5-FU and BUdR, the residual tumor is curetted thoroughly under general anesthesia. Surgery is performed through the sublabial window which has been kept open after the reduction surgery. Removal of the residual tumor mass which extends to the pterygomaxillary fossa, nasopharynx, anterior and medial skull base can be performed without difficulty, provided that the tumor mass is removed in pieces.(ABSTRACT TRUNCATED AT 250 WORDS)

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

[Histochemical study of external urethral sphincter in the rabbit. Analysis with construction of histograms].

Male rabbit's external urethral sphincter was examined by histochemical muscle fiber typing (myosin ATP-ase staining), and the analysis with construction of histograms regarding to muscle fiber types were performed. Rabbit's external urethral sphincter was predominantly composed of fast twitch (type 2) fibers (87.3%) as a whole. But the proportion of constituent fiber types varied according to the layers, i.e., the slow twitch (type 1) fibers constituted a relatively high percentage (33.4%) in the inner third layer, while few of the type 1 fibers were found in the outer third layer. The all histograms regarding to fiber type in different layers were normal bell-shaped distribution curves. The mena diameter of type 2 fibers (14.7 microns) was evidently larger than that of type 1 fibers (20.5 microns). All three kinds of muscle fibers equally tended to increase in size toward the outer direction, and in every three layers, the diameter of type 2 was larger than that of type 1 also. The definite differences in the proportion of fiber types and fiber sizes between layers may implicate that the inner and outer layers play different roles, i.e., continuous tonic constriction in the former and sporadic strong constriction of short duration in the latter, under different neural regulations. As far as rabbit's external urethral sphincter is concerned, sporadic strong constriction should be mainly dependent on the muscle fibers of large size composing the outer layer, especially the fast twitch fibers. It is possible that the rabbit is so adapted that it could interrupt urination promptly.

Animals↗
PubMed1989

[Report of a case of Herpes zoster].

Herpes Zoster is a viral disease of the skin and mucosa characterized by grouped vesicula eruptions and neuralgic pain along a peripheral nerve. A case of Herpes Zoster in the right region along the second and third trigeminal nerve branches of a 24-year-old male was reported. The first disorder appeared as a grouped vesicular eruption in the center of the lower lip. This was followed by a cutaneous lesion in the area of the right second trigeminal nerve branch. From the first day of hospitalization, the patient began receiving a daily dose of 2500mg of immunoglobulin. The administration of immunoglobulin, cured the oral and cutaneous lesion.

Adult↗