Search PubMed⌕ Search

Biomedical subjects

A Shibata

Publications and source records attributed to A Shibata.

At least 469 records · Page 26Linked to original sources

A case of heterozygous Fabry's disease with a short PR interval and giant negative T waves.

A 55 year old woman with heterozygous Fabry's disease presented with cardiac symptoms. The electrocardiogram showed a PR interval of 0.12 s and giant negative T waves, suggesting apical hypertrophic cardiomyopathy. Endomyocardial biopsy, however, revealed myelin like substances characteristic of Fabry's disease. Increasing thickness of the left ventricular wall was seen by echocardiography over a period of five years. A deficiency of alpha galactosidase activity in the leucocytes confirmed the diagnosis of Fabry's disease, although this patient had neither angiokeratoma or proteinuria. The possibility of Fabry's disease should be considered in patients with cardiomegaly of unknown cause and the following electrocardiographic abnormalities: a PR interval less than or equal to 0.12 s, high voltage QRS complexes in the left precordial leads, and giant negative T waves.

Electrocardiography↗

Squamous cell cancer of the maxillary sinus in Hokkaido, Japan: a case-control study.

A case-control study of squamous cell cancer of the maxillary sinus was performed in Hokkaido with 106 cases and 212 controls matched for sex, age (within five years), and residence (same health centre region). Univariate analyses showed that a history of chronic sinusitis (relative risk, RR = 3.2), nasal polyps (RR = 5.0), an occupational history of being a carpenter, joiner, furniture worker, or other woodworker (RR = 2.9), and current or past smoking habits (RR = 3.0) were statistically significant risk factors for men. No single item was a significant risk factor for women.

Carcinoma, Squamous Cell↗

Von Willebrand factor fragment in type IIA von Willebrand's disease: demonstration of two different forms of fragments.

A fast-migrating precipitin peak which showed a reaction of partial immunochemical identity with the major von Willebrand factor (vWf) component was detected by crossed immunoelectrophoresis in agarose gel in plasma but not in platelets from a patient with type IIA von Willebrand's disease (vWD). Another patient undergoing urokinase therapy had a vWf fragment in plasma which was antigenically cross-reactive with the major vWf component. When plasma from both patients was mixed and electrophoresed together in the first dimension, two fast-moving precipitin arcs were demonstrated in the second dimension. These data indicate that two different kinds of vWf fragments can be generated in vivo.

Electrophoresis, Agar Gel↗

Heat-treated factor VIII/von Willebrand factor concentrate in platelet-type von Willebrand's disease.

Cryoprecipitate has proved to correct the hemostatic defects in von Willebrand's disease (vWD) and platelet-type vWD. However, recent studies have revealed that transmission of the AIDS retrovirus (HIV) occurs through exposure to blood products including cryoprecipitate. Treatment with heat-treated factor VIII/von Willebrand factor (vWf) concentrates may have certain advantages over treatment with nonheated products, if these preparations are efficacious in these disorders. We found that a commercially available factor VIII/vWf concentrate, Haemate P, contained the high-molecular-weight multimers of vWf and had a ratio of ristocetin cofactor (RCof) to vWf antigen (vWf:Ag) close to unity. In addition, its capacity to directly induce aggregation of platelet-type vWD platelets in vitro was similar to that for cryoprecipitate. When infused into a patient with platelet-type vWD, Haemate P shortened the prolonged bleeding time and caused spontaneous platelet aggregation in vitro with a mild diminution of platelet count. These results indicate that some of the heat-treated factor VIII/vWf concentrates may provide a safer, yet still effective, treatment for platelet-type vWD.

Factor VIII↗

Early experiences of endocardial catheter mapping of the left ventricle in patients with sustained ventricular tachycardia--efficacy, safety and complications.

In 23 patients with recurrent sustained ventricular tachycardia (VT) which originated from the left ventricle, endocardial catheter mapping has performed. In an additional 14 patients we also stimulated their left ventricle for non-sustained VT. Multiple sites could be mapped for the recording of local electrical activity, for pacing and for the induction of VT. These procedures could be done without complication. A careful, reasonable, and safe method of endocardial mapping will facilitate clinical electrophysiologic study.

Adult↗

Potency and receptors involved in coronary vasoconstriction caused by neuropeptide Y(NPY).

Using anesthetized dogs, the coronary vascular effects of neuropeptide Y (NPY) were studied and the action of alpha- or serotonergic receptor blockade on the action of NPY was evaluated. To demonstrate the biological significance of the action of NPY, the vasoconstrictor potencies of NPY and norepinephrine were compared. One to 5 nmol of intracoronary NPY reduced coronary flow in a dose-dependent manner. The action started rather gradually and lasted for 10 min or more. Since perfusion pressure and central venous pressure were unchanged, the decrease in coronary flow should be a result of coronary vasoconstriction. Intracoronary norepinephrine infusion caused vasodilatation but when dogs were pretreated with 0.5 to 1.0 mg/kg of systemic propranolol, a vasoconstrictor effect was observed at a 5 times higher dose than with NPY. Furthermore, the action of NE was only transient, lasting for 30 sec or less. The vasoconstrictor action of NPY was not antagonized by phentolamine or by ketanserin. Since NPY is an endogenous polypeptide found in the sympathetic nerve terminals around coronary arteries, it may participate in the regulation of coronary flow.

Animals↗

A family case with autosomal-dominantly inherited pituitary dwarfism.

Isolated growth hormone (GH) deficiency (IGHD) is detected in 1/10 of pituitary dwarfism, but there are only a few reports on IGHD as an autosomal-dominant trait. We found one family with autosomal-dominantly inherited IGHD and examined their pituitary functions and GH genomes. Brothers (9.5 year and 11 year) and their mother (37 year) were diagnosed as having IGHD and their grandmother and uncle also seemed to have IGHD. All of their heights were under "mean-4.0 S.D.". Cerebral tomography of brothers and their mother all showed "empty sella", and GH-releasing hormone (GRH) tests showed no responses of GH not only to bolus intravenous injections but also after repeated intramuscular injections of GRH (100 micrograms/day) for 7 days. Although genetic analysis (Southern blotting method) could not detect any mutations in their GH genomes, the IGHD lesion of them seemed to be pituitary in origin.

Adult↗

Evaluation of fibrinolytic therapy by measuring cross-linked fibrin derivatives and plasmin-alpha 2-plasmin inhibitor complex in plasma.

Plasma levels of alpha 2-plasmin inhibitor (alpha 2PI), plasmin-alpha 2PI complex and cross-linked fibrin derivatives (XDP) were measured in 8 patients (12 episodes) with thromboembolic disorders on the initial administration of urokinase. In conjunction with a decrease in plasma alpha 2PI activity and antigen, plasmin-alpha 2PI complex increased following urokinase infusion in all cases except one who received a low dose (60,000 units) of urokinase. However, changes in XDP were variable among the patients. Plasma XDP level increased markedly in one, moderately in 4, slightly in one, and remained unchanged in 6 cases (episodes). The increment of plasma XDP correlated (r = 0.804, p = 0.003) with the dose of urokinase administered, but was independent of changes in plasmin-alpha 2PI complex. The plasma XDP elevation was associated with clinical improvement. These results suggest that simultaneous measurements of XDP and plasmin-alpha 2PI complex in plasma would be valuable for the pharmacological or hemostatic assessment of thrombolytic therapy.

Adult↗

Cell surface phenotyping of megakaryoblasts.

Surface phenotypic characterization of megakaryoblasts, identified by platelet peroxidase activity, was investigated in four patients who showed increased proliferation of megakaryoblasts: one patient with typical features of acute leukemia, one presenting with acute myelofibrosis, and two with Down's syndrome in whom blasts disappeared spontaneously (transient abnormal myelopoiesis, TAM). MY10 and/or MY9 antigens were expressed on the surface of some megakaryoblasts, but MY7, and MY4, antigens specific to granulocytic or monocytic cells, were not. Some megakaryoblasts were positive for only anti-HLA-DR antibodies. It was speculated that, during the differentiation of the megakaryocytic lineage, MY9 antigen appears transiently on the surface of megakaryoblasts that have lost HLA-DR antigens and have gained the glycoprotein IIb/IIIa antigen. This study also demonstrated that the proliferating blasts in some patients with TAM were mainly megakaryoblasts and suggested that the target cells in TAM are CFU-GEMM.

Adolescent↗

Bipotential cell differentiation of KU-812: evidence of a hybrid cell line that differentiates into basophils and macrophage-like cells.

KU-812-F is a subclone of KU-812, which has cytological features similar to the parent clone, and which carries the Philadelphia chromosome. We studied the effects of various chemical agents and serum-free culture (SF-C) condition on its differentiation. The KU-812-F subclone differentiated into macrophage-like cells with phorbol myristate acetate (PMA), but not with other agents. Unexpectedly, under SF-C, KU-812-F cells differentiated into mature basophil-like cells, and the histamine content of cell lysates increased in proportion to maturation. The addition of the condensed supernatant of SF-C promoted the cloning efficiency of KU-812-F cells in semisolid SF-C, whereas the cloning efficiency was reduced in SF-C alone. KU-812-F cells expressed myelomonocytic antigens. Additionally, My4 was induced with PMA and SF-C, but less often. HLA-DR was not expressed in any culture conditions, despite blastic morphology of KU-812-F cells or macrophage-like cells induced with PMA. The IgE receptor could not be demonstrated under any conditions. Correspondingly, immature and mature KU-812-F cells did not respond to anti-IgE or concanavalin A (con A), while histamine release was induced with PMA. In conclusion, KU-812-F belongs to the myeloid cell lineage and is at least a bipotential cell that can differentiate into basophils and macrophage-like cells. Although the functions appear to be dissimilar to those of normal basophils, the KU-812-F cell line may be a good model for basophil differentiation. Moreover, KU-812-F cells may provide new insights because they grow in semisolid culture by an autostimulating mechanism.

Basophils↗