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Biomedical subjects

S Shimada

Publications and source records attributed to S Shimada.

At least 325 records · Page 18Linked to original sources
PubMed1989

Metabolism of drugs in the eye. Menadione-dependent reduction of tertiary amine N-oxide by preparations from bovine ocular tissues.

As described previously, the microsomes and cytosol from bovine ciliary body exhibited a significant reductase activity toward tertiary amine N-oxide such as imipramine N-oxide when supplemented with menadione. In the present study, the menadione-dependent N-oxide reduction was further examined with preparations of bovine ocular tissues. The reduction of imipramine N-oxide occurred much more significantly when the microsomes and cytosols from bovine ciliary body were supplemented with both menadione and NAD(P)H, compared with menadione alone. The cytosolic menadione-dependent reduction, but not the microsomal one, was markedly inhibited by dicumarol, suggesting the involvement of DT-diaphorase in the reaction. Localization of the menadione-dependent N-oxide reductase activity in bovine ocular tissues indicated that the highest activity resided in the ciliary body, followed by retinal pigment epithelium-choroid, iris, retina and cornea. When the cytosol from bovine ciliary body was fractionated with ammonium sulfate, the distribution of the menadione-dependent N-oxide reductase activity in the resultant fractions was parallel, but roughly, to that of DT-diaphorase activity, supporting the assumption that the flavoenzyme was involved in the cytosolic menadione-dependent N-oxide reduction. We proposed a new mechanism for the metabolic reduction of tertiary amine N-oxide in the eye: Menadione is reduced to the corresponding diol by quinone-reducing enzymes and then tertiary amine N-oxide is reduced by the diol to the corresponding amine nonenzymatically.

Animals↗
PubMed1989

Purification of aldehyde oxidase from bovine ciliary body.

Ocular aldehyde oxidase was purified for the first time from bovine ciliary body cytosol by ammonium sulfate fractionation and successive HPLC using DEAE anion-exchange and hydroxyapatite columns. The purified enzyme was homogeneous by the criterion of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular weight of the enzyme was estimated to be about 150,000 by electrophoresis and to be about 300,000 by gel filtration HPLC on a TSK gel G3000SWXL column, indicating that the enzyme consists of two subunits with the same molecular weight. On the other hand, nicotinamide N-oxide reductase activity was associated with aldehyde oxidase activity throughout the purification steps of the latter enzyme. This fact indicated that nicotinamide N-oxide reductase activity of the ciliary body cytosol is due to aldehyde oxidase present in the tissue preparation.

Aldehyde Oxidase↗
PubMed1989

[Clinical study of the effect to myocardial protection with crystalloid cardioplegic solution during open heart surgery in infants under age 3 months].

We investigated the effect to myocardial protection with crystalloid cardioplegic solution (Kurume solution I (S-I)) during open heart surgery in 21 infants less than 3 months old. The mortality was 28.6% (6 cases) including 2 patients having peroperative severe acidosis or shock. It was suggested that about half of them died of inadequate myocardial preservation. Comparing factors in the deaths with the survivors, there were significant differences between them in extracorporeal circulation time (ECCT) (196.7 +/- 50.1 min versus 133.2 +/- 45.8 min, p less than 0.01) and aortic-cross clamping time (ACCT) (120.0 +/- 45.8 min versus 78.3 +/- 30.5 min, p less than 0.05). In survivors, 86.7% of them required the effective dose (more than 6 micrograms/kg/min) of catecholamine and 33.3% presented low cardiac output syndrome (with the dose of more than 10 micrograms/kg/min and more than for 48 hours). The incidence of LOS was related to ECCT and ACCT. Thus it seemed that infant was more susceptible than older patient to the effects of ECC and the operation was carried out safely with ECCT less than 150 minutes and ACCT under age 3 months, it is necessary to use the cardioplegic solution fitting immature myocardium and to design operative technique and assist device for open heart surgery to shorten ECCT and ACCT.

Cardiac Surgical Procedures↗
PubMed1989

[Four successfully operated cases of ball thrombus in the left atrium].

The authors report four cases of the left atrial ball thrombus associated with mitral stenosis. Three of four which had floating ball thrombus in the left atrium presented with syncopal attacks and systemic embolism. Echocardiography was the most effective method for preoperative diagnosis of ball thrombus in the left atrium and mitralstenosis. After having accurate diagnosis of ball thrombus in the left atrium by echocardiogram, all of cases were treated urgently with removal of the thrombus and mitral valve replacement or mitral commissurotomy. During operation, the head down position and slight right lateral position had been maintained to prevent the impaction of the ball thrombus into mitral valve orifice and the immediate cardiopulmonary bypass by ascending aortic, superior and inferior venous cannulation were placed through midsternal splitting incision. Because of high frequency of peripheral embolism and sudden death, left atrial ball thrombus should be recommended to be removed urgently.

Aged↗
PubMed1989

[Clinical study on alcoholic pancreatitis in alcoholics (especially in ERP findings)].

The pancreatic functions (PFD test and 75g GTT), pancreatic enzymes (serum-amylase, urine-amylase, serum-elastase I and serum-lipase), alcohol consumption histories, clinical symptoms, histological findings in the liver and ERP findings have been examined in 66 alcoholic patients. Fourty two out of 66 cases (64%) showed abnormal ERP findings which were compatible with chronic pancreatitis. But among these 42 cases, only 9 cases (21%) showed clinical symptoms such as epigastralgia, back pain, diarrhea and emaciation which suggest the existence of chronic pancreatitis. The degree of liver damage, alcohol consumption have no significant correlation with ERP findings. Furthermore, the severe alcoholic pancreatitis occurred in patients having mild liver injury more than those having severe liver injury such as cirrhosis. And the data of pancreatic functions and enzymes could not confirm ERP findings especially in patients with mild and moderate pancreatic injury when compared to normal ERP findings. We concluded that asymptomatic alcoholic pancreatitis occurred more frequently in painless alcoholic. It may be not suitable for only using the normal pancreatic functions test to diagnose the alcohol induced chronic pancreatitis.

Adult↗
PubMed1989

[A case report of aortitis syndrome with massive aortic regurgitation (AR), and ostial stenosis of the right coronary artery].

A 55-year-old female with massive aortic regurgitation and ostial stenosis of the right coronary artery due to aortitis syndrome was reported. The patient was admitted to the hospital with anterior chest pain and dyspnea on exertion. Retrograde aortogram showed massive aortic regurgitation and selective coronary angiogram revealed ostial stenosis of the right coronary artery. She was treated with aorto-coronary bypass (A-C bypass) and aortic valve replacement (AVR) with St. Jude Medical prosthetic valve. At operation, ostial stenosis of the right coronary artery due to aortitis syndrome was confirmed. Aortic valve replacement with a prosthetic valve and saphenous vein grafting to the distal right coronary artery were performed. Steroid therapy was started immediately after the operation. She recovered well and no complications was recognized after the operation.

Aortic Arch Syndromes↗
PubMed1989

[Studies of pathogenicity of GVHD induced by blood transfusion after open heart surgery].

We compared the case like acute GVHD (graft versus host disease) induced by blood transfusion with the cases after open heart surgery which received blood transfusion by the measurement of cell-mediated immunity. Furthermore, we investigated the etiology of GVHD in comparison with cases according to age. Seventy-three cases (under 60 years old: 55 cases, over 60 years old: 18 cases) underwent open heart surgery and the mean blood transfusion volume was 2368cc and the mean age was 52.8 years old. After open heart surgery the rate of peripheral OKT3+ and OKT4+ cells, lymphocyte transformation and IL-2 (interleukin 2 product) were significantly decreased at postoperative day (POD) 1 and recovered to preoperative value until POD 14. However, in the cases like GVHD the rate of OKT4+ cell was decreased in contrast with the change of OKT8+ cell, and lymphocyte transformation and IL-2 production did not recover to normal range postoperatively. In conclusion, in the cases like GVHD the postoperative charge of cell-immunity is similar to the acute GVHD induced after bone marrow transplantation and we must take care about the blood transfusion to the older patients after open heart surgery because there is a possibility that cell-mediated immunity may be more depressed in the elder patient pre and postoperatively.

Acute Disease↗
PubMed1989

[A brief respite from hospital: home mechanical ventilation for children in Japan].

Children who require prolonged respiratory support often have to spend their whole lives in the hospital. It is important, however, for these children to have time with their families in their own homes. Home mechanical ventilation can make it possible. In Japan, the concept of home mechanical ventilation has just begun to open up. We reported five cases of home mechanical ventilation for children by using a portable respirator (Bennett, Companion 2800). Two cases of these were patients with hypoxic ischemic encephalopathy. The others were cases with neuro-muscular diseases (Werdnig-Hoffmann disease, mitochondrial myopathy, myotubular myopathy). Before taking the patients out, parents received a training in nursing procedures and in skillful use of the ventilator and equipment. The patients went out on excursions 17 times, and were released for home stay a total of 25 times. Initially, 12 excursions were undertaken with doctors or nurses in attendance; later, however, all of the home stays and 5 of the excursions were carried out successfully by the family only. They went to places such as their own home, a park, a zoo, an aquarium and a museum. The average time was 4.6 hours (3-8 hours) for excursions, and 1.8 days (1-7 days) for home stays. Questioning of family revealed that home mechanical ventilation accelerated the social and emotional development of these children whose condition necessitated respiratory support, especially patients with neuro-muscular diseases. It also revealed that family could accept the patient as a member with more familiarity and with more ease.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1989

[Cineradiographical significance for diagnosis and treatment of thrombosed Björk-Shiley prosthesis in the aortic position].

In the periods between February 1973 and December 1987, 377 Björk-Shiley valve prostheses have been implanted in the aortic position in our institute. The maximum opening angle of the prosthesis have been cineradiographically measured in 30 cases. The maximum opening angle of the convexo-concave valve having an opening angle of 60 degree (CC 60) was measured as 58.8 +/- 1.9 degree and that of the monostrut valve having an opening angle of 70 degree was 69.4 +/- 2.1 degree. During this period we have experienced 6 cases of thrombosed Björk-Shiley prosthesis. They have shown restriction of the opening from 26 to 58.9 degree and restriction of the closing from 9.2 to 41.8 degree. Thrombolytic treatment was successful in case with thrombosed Björk-Shiley prosthesis which showed restriction of the opening angle on cineradiogram. 4 cases with restriction of the closing angle on cineradiogram were treated operative thrombectomy. Three of them have had uneventful reoperative course in the follow up period of 8 years. We believe that cineradiography is very useful for not only diagnosis but also decision of management for thrombosed Björk-Shiley prosthesis in the aortic position.

Adolescent↗
PubMed1988

Ontogeny of calcitonin gene-related peptide-immunoreactive structures in the rat forebrain and diencephalon.

Ontogeny of the calcitonin gene-related peptide (CGRP)-containing structures was investigated in the forebrain and diencephalon of the rat by means of indirect immunofluorescence. CGRP-like immunoreactive (CGRP-IR) fibers first appeared at gestational day 18 (E18) in the primordia of the bed nucleus of the stria terminalis, central amygdaloid nucleus and posterolateral portion of the lateral hypothalamic nucleus. CGRP-IR fibers gradually increased in immunoreactivity and in number in these nuclei toward birth. A pronounced increase of CGRP-like immunoreactive fibers was found after birth in these nuclei and made very dense plexuses of fibers in adult animals. A few CGRP-IR fibers first appeared at the perinatal stage in the lateral septum, the most caudal portion of the caudate-putamen, and ventromedial and ventroposterior thalamic nuclei. Then the immunoreactive fibers increased and dense plexuses were present in these brain areas of the adult. A small number of immunoreactive fibers appeared at postnatal day 4-7 (P4-7) in the caudal insular cortex and ventromedial hypothalamic nucleus. A significant number of fibers was present in these areas of the adult. On the other hand, CGRP-like immunoreactivity in cell bodies was first detected with faint immunofluorescence at P4 in the anteromedial parts of the lateral hypothalamic area and ventromedial and ventroposterior thalamic nuclei. Thereafter CGRP-IR cells increased in immunoreactivity, and a significant number of cells was noted in these nuclei of the adult. In addition, CGRP-IR cells are identified in the medial amygdaloid nucleus, and medial preoptic area at P14. In conclusion, in the forebrain and diencephalon (1) CGRP-like immunoreactivity appears in fibers earlier than in cell bodies, suggesting that at least some of immunoreactive fibers originate from the lower brainstem, and (2) high density of CGRP-IR structures present in the brain at embryonic and early postnatal stages may indicate that CGRP could be an important factor involved in the developmental organization of the central nervous system.

Aging↗
PubMed1988

Neuropeptide Y-immunoreactive neurons receive synaptic inputs from dopaminergic axon terminals in the rat neostriatum.

Double immunocytochemistry using peroxidase-antiperoxidase and protein A-gold was performed to determine whether neuropeptide Y (NPY) immunoreactive neurons receive synaptic inputs from catecholaminergic axon terminals in the rat neostriatum. Tyrosine hydroxylase-immunoreactive axons were found to be in synaptic contact with the somas and proximal dendrites of NPY-immunoreactive neostriatal neurons. These latter neurons were medium-sized and had indented nuclei, and thus were thought to be medium aspiny interneurons. Thus nigrostriatal dopaminergic neurons may monosynaptically influence striatal NPY neurons.

Animals↗
PubMed1988

A human macrophage hybridoma producing a cytotoxic factor distinct from TNF, LT, and IL-1.

A stable human macrophage hybridoma was established by somatic cell fusion between human peripheral blood monocyte-derived macrophages and an 8-azaguanine resistant clone of a human histiocytic lymphoma cell line U-937 (clone U-937-F9). The hybrid cell line (F9P) exhibited typical macrophage-like morphology and had 30 more chromosomes than U-937-F9 cells. Its macrophage characteristics were confirmed by the manifestation of intracellular nonspecific esterase, the detection of Mo-2 and LEU-M3 antigens on the cell surface, and the demonstration of phagocytic activity. Furthermore, when stimulated with lipopolysaccharide (LPS), this cell line could secrete a considerable amount of a cytotoxic factor (CTF). Distinct from the hybrid cell line, the parental U-937-F9 cells expressed neither Mo-2 nor LEU-M3 antigens on the cell surface, did not show phagocytic activity, and their culture supernatants did not show cytotoxic activity even after LPS stimulation. The activity of CTF in the culture supernatant of the LPS-stimulated hybrid cells could not be neutralized with anti-tumor necrosis factor, anti-interleukin-1, or anti-lymphotoxin antibodies. The CTF had a relative molecular mass of 45-60 x 10(3) daltons as determined by gel filtration on a column of Superose 12, and an isoelectric point of 5.1. The cytotoxic activity was also induced when the hybrid cells were stimulated with the concentrated supernatants of a human T-cell hybridoma containing macrophage activating factor for cytotoxicity or with LP3 tumor cells which were used as target cells.

Antibodies↗
PubMed1988

Ontogeny of the calcitonin gene-related peptide in the nervous system of rat brain stem: an immunohistochemical analysis.

The ontogeny of the calcitonin gene-related peptide in the neuron system of the rat brain stem was investigated by means of the indirect immunofluorescence technique. Calcitonin gene-related peptide-like immunoreactivity was first detected in the fibers of the nucleus of spinal tract trigeminal nerve on gestational day 18, and thereafter appeared gradually in various brain stem areas such as in the fibers of the solitary tract, gracile nucleus, cuneate nucleus, inferior colliculus, superior colliculus, medial geniculate nucleus and in the neurons of the hypoglossal nucleus, facial nucleus, superior olive, parabrachial area, superior colliculus and peripeduncular nucleus. In colchicine-untreated animals, the immunoreactive fibers increased in number and reached adult level by postnatal day 14, whereas the number of cells reached a maximum between postnatal days 2 and 6 and then decreased in number and immunoreactivity or disappeared, except in some areas such as the superior olive and peripeduncular nucleus, which showed the same immunoreactivity as for adult animals. With colchicine treatment, calcitonin gene-related peptide-like immunoreactive cells were found in more areas of the brain stem such as the abducens nucleus, parabigeminal nucleus, principal oculomotor nucleus, trochlear nucleus and central gray, along with the nuclei which had shown calcitonin gene-related peptide immunoreactivity in the untreated animals. However, the neurons in the inferior olive showed a different ontogenetical pattern of calcitonin gene-related peptide of immunoreactivity. Immunoreactivity disappeared completely by postnatal day 21 in both colchicine-untreated and -treated animals.

Aging↗
PubMed1988

The surgical treatment of aortic regurgitation secondary to aortitis.

We describe the operative and perioperative management of 11 patients with aortic regurgitation due to aortitis. All patients required aortic valve replacement because of severely uncoapted cusps secondary to dilatation of the ascending aorta. The right coronary ostium was narrowed in 5 patients and consequently necessitated a smaller coronary tip for the administration of cardioplegic solution. To implant the prosthetic valve, pledgeted 2-0 Tevdek sutures were placed through the aortic valve annulus either from the ventricular side or from outside the aortic wall. Steroids were administered to 4 patients preoperatively and 8 patients postoperatively. Postoperative dehiscence of the prosthesis was seen in 1 of the 3 patients not given any steriods. We conclude that it is important to arrest the inflammatory reaction before operation and if the aortic valve must be replaced, to reinforce the implanted prosthesis with pledgeted sutures. Also, we suggest the possible importance of steroid therapy.

Adult↗
PubMed1988

The moment of intraventricular hemorrhage.

A continuous monitoring of the germinal layer by linear scanning ultrasound has been proposed for the purpose of ascertaining the moment of intraventricular hemorrhage (IVH). Using a VHS videotape, we performed the 48 hours monitoring in 7 immature infants weighing less than 1,000 g who required respiratory support. Four cases of these developed IVH. In one case, which was 755 g in birth weight and 24 weeks in gestational age, the moment of IVH was successfully demonstrated on the ultrasonic monitor. At that moment, there were no significant changes in heart rate and systemic blood pressure. No direct manipulation or treatment, such as an endotracheal suctioning or a heel puncture which might induce a blood pressure fluctuation, was being given at the moment of IVH. About 15 minutes after the episode, abnormal seizure-like movement periodically developed.

Blood Pressure↗
PubMed1988

In vitro augmentation of natural killer cell activity and production of interferon-alpha/beta and -gamma with deoxyribonucleic acid fraction from Mycobacterium bovis BCG.

A nucleic acid-rich fraction extracted and purified from BCG (MY-1) augmented natural killer (NK) cell activity of mouse spleen cells in vitro, and produced factor(s) which showed anti-viral activity and rendered normal macrophages cytotoxic towards tumor cells. These cellular responses were induced by the MY-1 digested preliminarily with RNase, but not by the MY-1 digested with DNase, indicating that DNA contained in MY-1 was essential for the responses. The function of the factor to activate macrophages was destroyed by treatment with a small amount of anti-interferon (IFN)-gamma antiserum or under acidic conditions (pH 2), but not by treatment with anti-IFN-alpha/beta antiserum, while the anti-viral activity was destroyed almost completely by treatment with anti-IFN-alpha/beta antiserum. It appears that DNA from BCG stimulated mouse spleen cells in vitro, resulting in augmentation of NK activity and production of IFN-alpha/beta and -gamma.

Animals↗