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Biomedical subjects

S Fujiwara

Publications and source records attributed to S Fujiwara.

At least 469 records · Page 26Linked to original sources
PubMed1986

Cryopreservation of human lymphocytes for assessment of lymphocyte subsets and natural killer cytotoxicity.

Cryopreservation of lymphocytes has become increasingly important, especially when the cells are to be used in retrospective studies of selected and dwindling populations, such as A-bomb survivors. This report describes an efficient method for cryopreservation of human lymphocytes which does not significantly alter various immunological characteristics of these cells. The proportions of Leu-1+ cells (T cells), Leu-2a+ cells (suppressor-cytotoxic T cells), Leu-3a+ cells (helper-inducer T cells), HLA-DR+ cells, Mo2+ cells (monocytes), B1+ cells (B cells), and Leu-7+ cells (natural killer (NK) cells), as determined by monoclonal antibodies, were found to be stable following cryopreservation. NK cell activity against K-562 target cells showed a 40-60% decrease immediately after thawing, but recovered to approximate pre-freezing levels after preincubation for 18 h. Neither lymphocyte subsets nor cell viability significantly changed following preincubation after cryopreservation. However, the ratio of cells binding to K-562 cells increased after this preincubation and may account for the observed recovery of NK cell activity. NK cell activity remained relatively stable up to 14 months of storage which confirms that freezing damage depends on the freezing process rather than on the duration of cryopreservation.

Antibodies, Monoclonal↗
PubMed1986

Production of human monoclonal antibodies against Epstein-Barr virus-specific antigens by the virus-immortalized lymphoblastoid cell lines.

The possible production of human monoclonal antibodies against Epstein-Barr virus (EBV) was assessed through the EBV immortalization technique. When individual lymphocyte samples from 50 clinical patients and healthy donors were immortalized by EBV, 4 lymphoblastoid lines yielded antibodies to EBV antigens. These positive lines were cloned and each line yielded cultures that secreted monoclonal antibodies against either viral capsid antigen (VCA) or membrane antigen (MA) component. Above all, a clonal line TAKA-SP-8 produced 5 micrograms MA antibody/10(6) cells/ml for more than 12 months. The culture fluid specifically immunoprecipitated a single polypeptide with a size of 93K from both P3HR-1 and B95-8 cell extracts. FUKA-SP-3, on the other hand, secreted 5 micrograms VCA antibody/10(6) cells/ml for at least 8 months. This antibody recognized two polypeptides with sizes of 123K and 120K, from P3HR-1 and B95-8 cell extracts, respectively. When B95-8 and P3HR-1 EBV were treated with the human MA monoclonal, both nuclear antigen (EBNA) synthesis and early antigen (EA) induction were strongly inhibited. All EBV antibody-producing cultures were exclusively achieved from splenic lymphocytes of patients with autoimmune diseases, but not from other donors.

Antibodies, Monoclonal↗
PubMed1986

Evolution of allantoinase and allantoicase involved in urate degradation in liver peroxisomes. A rapid purification of amphibian allantoinase and allantoicase complex, its subunit locations of the two enzymes, and its comparison with fish allantoinase and allantoicase.

Allantoinase and allantoicase are located in the same protein molecule in amphibian liver, whereas the two enzymes are different proteins in marine fish and invertebrate liver (Takada, Y., and Noguchi, T. (1983) J. Biol. Chem. 258, 4762-4764). The amphibian enzyme was rapidly purified from frog liver by using its following characteristics. 1) The enzyme binds to the intracellular membranes in the hypotonic solution. 2) The membrane-bound enzyme is not solubilized by the detergent. 3) The membrane-bound enzyme is solubilized by oxaloacetate. The electrophoresis of the purified enzyme gave a single protein band in the absence of sodium dodecyl sulfate, and gave two protein bands with molecular weights of 48,000 and 54,000, respectively, in the presence of sodium dodecyl sulfate. With a specific antibody raised against each subunit, allantoinase activity was found to be from the large subunit, and allantoicase activity to be from the small subunit. This amphibian allantoinase and allantoicase complex was compared with allantoinase and allantoicase purified from fish liver. Fish allantoinase was a single peptide and fish allantoicase was composed of two identical subunits. Fish allantoinase had an identical molecular weight with amphibian large (allantoinase) subunit and the subunit of fish allantoicase with amphibian small (allantoicase) subunit. These results suggest that the evolution of fish to amphibian resulted in the dissociation of allantoicase into subunits and in the association of allantoinase with allantoicase. The two enzymes are lost by further evolution.

Amidohydrolases↗
PubMed1986

Structure and function of basement membrane proteoglycans.

Basement membranes contain at least three different proteoglycans. These are a large, low buoyant density heparan sulphate proteoglycan and two smaller, high density proteoglycans with either heparan sulphate or chondroitin sulphate side-chains. The large (Mr 400K-600K and small (Mr 130K) heparan sulphate proteoglycans were purified from the mouse EHS tumour. These proteoglycans are immunologically related by sharing some protein core antigenic determinants (epitopes) but do not cross-react with cell-surface heparan sulphate proteoglycans or with proteoglycans from interstitial connective tissue. This indicates that they belong to a distinct family of proteoglycans. Structural models were developed, based on electron microscopy and analytical ultracentrifugation, demonstrating that the small proteoglycan contains on average four heparan sulphate chains of about 30 nm in length, while the large proteoglycan consists of three long (about 90 nm) heparan sulphate chains connected to one end of a large core protein. Single heparan sulphate chains were isolated from the EHS tumour proteoglycans and from the corresponding proteoglycans from Reichert's membrane of the mouse embryo. The heparan sulphate from Reichert's membrane bound to antithrombin with high affinity and was found to contain the unique 3-O-sulphated glucosamine residue previously identified in the antithrombin-binding region of heparin. The EHS tumour heparan sulphate showed a higher N-/O-sulphate ratio and a lower affinity for antithrombin.

Animals↗
PubMed1986

Evaluation of cerebral blood flow and metabolism in childhood moyamoya disease: an investigation into "re-build-up" on EEG by positron CT.

The cerebral blood flow and cerebral metabolic rate of oxygen (CBF and CMRO2) of three cases of childhood moyamoya disease were examined by positron-emission-computed tomography for the purpose of investigating the mechanism of the "re-build-up" phenomenon on EEG. Decrease in both CBF and CMRO2 were observed following hyperventilation. However, dissociation between the decrease in CBF and CMRO2 was also observed. Arterial blood-gas analysis disclosed hypocapnea during hyperventilation and hypoxia following hyperventilation. These results clearly indicate that the re-build-up seen on EEG is the manifestation not only of ischemic hypoxia but also of hypoxic hypoxia characteristically seen in moyamoya disease.

Adolescent↗
PubMed1986

Selective hemoglobin inhibition of endothelium-dependent vasodilation of rabbit basilar artery.

The effect of hemoglobin on endothelium-dependent vasodilation of the isolated rabbit basilar artery was examined using an isometric tension recording method. Acetylcholine (ACh) (10(-7) - (10(-4) M) evoked a dose-dependent vasodilation of isolated rabbit basilar artery previously contracted by 10(-6) M serotonin. This vasodilating action disappeared after removal of the endothelium. The ACh-induced vasodilation of rabbit basilar artery is thought to be strictly endothelium-dependent. Hemoglobin (10(-7) - 10(-5) M) inhibited this ACh-induced endothelium-dependent vasodilation conditional upon the dose. Adenosine triphosphate (ATP, 10(-7) - 10(-4) M) also relaxed isolated rabbit basilar artery already contracted by 10(-6) M serotonin. This vasodilating action was slightly inhibited by adenosine antagonist, 8-phenyltheophylline (8-PT), and markedly attenuated by removal of the endothelium. This ATP-induced vasodilation is thought to be composed of ATP itself (endothelium-dependent) and ATP degradation products (endothelium-independent) such as adenosine monophosphate or adenosine. Hemoglobin markedly inhibited ATP-induced vasodilation, but there still remained a small vasodilation, which was blocked by 8-PT. Papaverine-induced vasodilation was not affected by removal of the endothelium, and hemoglobin did not inhibit the papaverine-induced vasodilation. These results suggest that rabbit basilar artery has endothelium-dependent vasodilating mechanisms induced by ACh and ATP, and that hemoglobin selectively blocks the endothelium-dependent vasodilation. This finding may relate to the pathogenesis of cerebral vasospasm after subarachnoid hemorrhage: there is a possibility that the presence of hemoglobin released from lysed erythrocytes inhibits the endothelium-dependent vasodilation of cerebral arteries; furthermore, the endothelial degeneration following subarachnoid hemorrhage may impair the vasodilating mechanisms of cerebral artery smooth-muscle cells.

Acetylcholine↗
PubMed1986

[The pattern of left ventricular hypertrophy in hypertension and its relation to the hemodynamic and sympathetic responses to exercise].

A wide spectrum of cardiac hypertrophy has been observed in hypertensive patients. In this study, the responses of hemodynamics and sympathetic drives to exercise among hypertensive patients with various types of left ventricular hypertrophy were investigated. Twenty-five patients with untreated essential hypertension (WHO I and II) were classified as those with and without asymmetric hypertrophy (with AH, n = 7; without AH, n = 18) by their echocardiographic patterns. Ten normotensives served as controls. Exercise was performed on a braked bicycle ergometer; the initial work load was 50 watt. The work load increased progressively by 25 watt at three minute-intervals to the target heart rate, exhaustion, or positive ST.T changes. Blood pressure, heart rate, plasma norepinephrine and hemodynamic parameters by echocardiography were estimated at rest and during exercise. Systolic blood pressure and increased heart rate by exercise in all groups. In patients with AH, a rapid increase was observed, and the increase in systolic blood pressure at submaximum exercise was significantly greater than those in normotensives or patients without AH (p less than 0.05). During exercise, endsystolic dimension decreased in normotensives and in patients without AH (p less than 0.01), but the change was not significant in patients with AH. Percent fractional shortening and percent systolic wall thickening of the interventricular septum and left ventricular posterior wall increased significantly in normotensives and in patients without AH (p less than 0.05), but they were unaltered in patients with AH. Although plasma norepinephrine significantly increased in all groups by exercise, the increase in patients with ASH was greater than those in the other groups (p less than 0.05). These results suggest that hyperresponsiveness of systolic blood pressure and heart rate to exercise may play a role in the pathogenesis of AH, and that this type of hypertrophy could be associated with abnormalities of the sympathetic nervous system.

Adult↗
PubMed1986

Epstein-Barr virus infection and oncogenesis in primary immunodeficiency.

Lymphomas occurred in 3 of 16 Japanese patients with ataxia telangiectasia (AT) and Wiskott-Aldrich syndrome (WAS). The patients had a persistently reactivated Epstein-Barr virus (EBV) infection with a remarkable decrease in virus-specific cellular immunity. In these patients, the B lymphocytes were more sensitive to EBV-induced events and to cellular proto-oncogene activation than seen in the healthy counterparts. This immunologic and genetic background was considered to explain the massive lymphoproliferation in these primary immunodeficiency disorders.

Adolescent↗
PubMed1986

[A case of granulocytic sarcoma (chloroma) preceding acute leukemia].

A 2-year-old boy developed proptosis of the right eye in May 1982. He was admitted to Isawa Hospital on June 9. Physical examination revealed a well developed child with slight proptosis of the right eye and swelling of the right temple. Routine serologic and blood examination revealed no abnormality except LDH, ALP and LAP. CT scan showed high density area in the anterior part of the right temporal lobe and lateral wall of the right orbit. He underwent open-biopsy of this tumor on July 15. Eosinophilic granuloma was suspected, but definite diagnosis was not made. Second biopsy was performed at right upper gingiva on August 2. Follow-up CT scan revealed tumor invaded sphenoidal and maxillary sinus. The patient was transferred to Tohoku University Hospital on August 13. On admission myeloblasts appeared in peripheral blood, and bone marrow examination revealed acute myelo-monocytic leukemia. We discussed its difficulty of differential diagnosis in literature.

Antineoplastic Agents↗
PubMed1986

[A case showing angiographically moyamoya vessels combined with intracranial calcification].

This case was 36-year-old female with the past history of pulmonary tuberculosis on her 10 years old. During the treatment for pulmonary tuberculosis, transient tetraparesis appeared, and improved completely. She was admitted to our hospital, complaining sensory disturbance of left face and arm on July 25, 1983. Plain skull roentogenogram showed calcification at the base of brain. Computerized tomography (CT scan) showed dilatation of lateral and third ventricles. Cerebral angiograms revealed an occlusion of the right internal carotid artery and the left middle cerebral artery, the stenosis of the basilar artery and bilateral posterior cerebral arteries, transdural anastomosis (so-called vault moyamoya), leptomeningeal anastomosis and moyamoya vessels at the base of brain. Four days after the admission, left hemiplegia appeared suddenly. Because the findings of CT scan and angiogram showed no change, conservative treatment was performed and motor disturbance improved. Biopsy of the calcified mass was carried out and histological findings suggested an old inflammation. Based on the clinical course and examination, it was considered that moyamoya vessels of this case had been formed as a result of tuberculous meningitis. Up to now, only 6 cases with moyamoya vessels at the base of brain coursed by tuberculous meningitis Up to now, only 6 cases with moyamoya vessels at the base of brain coursed by tuberculous meningitis have been reported. In our case, neurological symptoms appeared 26 years after tuberculous meningitis and occlusive changes were seen in bilateral carotid system and vertebrobasilar system.

Adult↗