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Biomedical subjects

S Mikami

Publications and source records attributed to S Mikami.

At least 91 records · Page 5Linked to original sources

Heterogeneity of sugar composition of factor VIII/von Willebrand factor in von Willebrand's disease: analysis by crossed affinoimmunoelectrophoresis using lectin (ricinus communis agglutinin-120).

The nature of sugar chain of factor VIII/von Willebrand factor in plasma of normal subjects and patients with von Willebrand's disease (vWd) was examined by crossed affinoimmunoelectrophoresis using anti-human factor VIII rabbit serum, with inserted Ricinus communis agglutinin-120 (RCA-120) agarose layer (RCA - CIE). Molecular weights of factor VIII-related antigen (VIIIR:Ag) were estimated by SDS polyacrylamide gel electrophoresis - crossed affinoimmunoelectrophoresis (SDS PAGE - RCA - CIE). VIIIR:Ag, in normal plasma and in classical form of vWd, showed two precipitin peaks on RCA - CIE. The slower moving component of VIIIR:Ag with molecular weights over 3 x 10(6) daltons from normal subjects and patients with classical form of vWd showed a high affinity for RCA-120. The faster moving component of VIIIR:Ag below 3 x 10(6) daltons from the above-mentioned subjects and patients with a variant form (Type IIA) showed a very weak affinity for RCA-120. These results suggested that all of VIIIR:Ag in these variant cases may have a deficiency of galactose residues reactive with RCA, in addition to an incomplete polymerization of VIIIR:Ag, similar to that of the faster moving component of normal subjects.

Blood Coagulation Factors↗

Effects of caffeine on pancreatic tumorigenesis by 4-hydroxyaminoquinoline 1-oxide in partially pancreatectomized rats.

The effects of caffeine on pancreatic tumorigenesis by 4-hydroxyaminoquinoline 1-oxide (4-HAQO) and on pancreatic DNA synthesis were studied in partially pancreatectomized male Wistar rats. 4-HAQO was injected i.v. as a single dose of 7 mg/kg body weight 3 days after partial pancreatectomy. Caffeine was injected s.c. every 12 h at the maximum tolerated dose (m.t.d.) of 120 mg/kg body weight, half the m.t.d., and one quarter the m.t.d. from 12 to 72 h before and 0 to 72, 72 to 132, and 0 to 132 h after 4-HAQO treatment. Post-treatment with caffeine from 0 to 132 h had a dose-dependent biphasic effect on pancreatic tumorigenesis: post-treatment with the m.t.d. of caffeine decreased the total number of nodules, whereas treatment with one quarter the m.t.d. of caffeine increased their number. Decrease in the number of nodules was also observed on post-treatment with the m.t.d. of caffeine from 0 to 72 or from 72 to 132 h. Pretreatment with the m.t.d. of caffeine had no significant effect on the number of nodules. Recovery of pancreatic DNA synthesis was slower after simultaneous treatment with the m.t.d. of caffeine and 4-HAQO than after treatment with 4-HAQO alone. The possible mechanism of the effect of caffeine on pancreatic tumorigenesis induced by 4-HAQO in rats is discussed.

4-Hydroxyaminoquinoline-1-oxide↗

Possible role of poly(ADP-ribose) polymerase on the early stage of liver carcinogenesis by diethylnitrosamine in rats.

In the present experiments, we studied the effect of poly(ADP-ribose) polymerase inhibitors on the early stage of liver carcinogenesis by diethylnitrosamine (DEN) in rat liver in order to clarify the biological role of this enzyme in cancer induction. We used 3-aminobenzamide(ABA), 5-methylnicotinamide(MNam), and thymidine as the inhibitors and measured the numbers and sizes of gamma-glutamyltranspeptidase (gamma-GTP) positive foci as a marker of initiated cell populations. When ABA was given within 4 hr after DEN treatment, it had almost the same effect as a partial hepatectomy and caused dose-dependent enhancement of the induction of gamma-GTP positive foci. The administration of ABA at a dose of 600 mg/kg was effective to enhance the induction of the foci 1 day before to 1 day after 20 mg/kg DEN initiation. The enhancing effect of MNam and thymidine at a dose of 600 mg/kg was observed to the same extent as that of ABA. Based on these results the experiments were extended to the mechanisms of the enhancing effect of ABA. Liver cell necrosis was not detected by measuring serum GOT and GPT levels and histology after DEN and ABA administration. Further, the initiating and promoting activities of ABA in liver carcinogenesis were studied and ABA per se was not found to take part in either activity. These results indicate that poly(ADP-ribose) polymerase plays an important role in the early stage of liver carcinogenesis by DEN and provides a new avenue for studying the mechanisms of the initiation process in chemical carcinogenesis.

Alanine Transaminase↗

Immunohistochemical localization of vasoactive intestinal polypeptide (VIP)-containing neurons in the hypothalamus of the Japanese quail, Coturnix coturnix.

The localization of vasoactive intestinal polypeptide (VIP) in the hypothalamus of the quail has been studied by means of light- and electron-microscopic immunohistochemistry. Numerous VIP-immunoreactive perikarya are distributed in the caudal portion of the nucleus infundibularis (n. tuberis) and nucleus mamillaris lateralis, and sparse in the preoptic area, nucleus supraopticus and nucleus paraventricularis. Dense localization of immunoreactive-VIP fibers is observed in the external layer of the median eminence, in close contact with the primary portal capillaries. The main origins of these fiber terminals are VIP-immunoreactive perikarya of the nucleus infundibularis. These neurons are spindle or bipolar and extend one process to the ventricular surface and another to the external layer of median eminence. They are CSF-contacting neurons and apparently constitute the tuberohypophysial tract that links the third ventricle and the hypophysial portal circulation. VIP-reactive neurons in the nucleus mamillaris lateralis also project axons to the external layer of the median eminence, constituting the posterior bundle of the tuberohypophysial tract. Numerous VIP-immunoreactive perikarya occur also in the nucleus accumbens/pars posterior close to the lateral ventricle. They are also CSF-contacting neurons extending a process to the lateral ventricle. There are moderate distributions of VIP-reactive fibers in the area ventralis and in the area septalis. Ultrastructurally, the immunoreactive products against VIP are found in the elementary granules, 75-115 nm in diameter, within the nerve fibers in the median eminence.

Animals↗

Haemophilia B in a girl.

Haemophilia B is extremely rare in females and so far 20 cases have been reported. A 9-year-old girl with severe haemophilia symptoms is described, who shows a very low level of factor IX activity (1.5%) and antigen (less than 10%), normal XX female karyotype and negative family history of bleeding tendency or consanguinity. This case is probably the fourth report of sporadic female haemophilia B without chromosomal aberration and the first one with quantitative analysis by immunoradiometric assay and enzyme-linked immunosorbent assay of factor IX antigen. This very low factor IX level and severe bleeding tendency of the patient would be consistent with the homozygous state, but since a double mutation is extremely rare the patient's laboratory findings can be more easily explained by extreme lyonization of the normal X-chromosome of a heterozygous carrier.

Child↗

Congenital deficiency of alpha 2-plasmin inhibitor in three sisters.

3 young Japanese sisters with congenital alpha 2-plasmin inhibitor (alpha 2-PI) deficiency are reported. They have mild umbilical bleeding and/or repeated prolonged bleeding after minor trauma, but rarely spontaneous bleedings. The most characteristic hemostatic findings were shortened whole blood clot lysis time and euglobulin lysis time. Activities of all hemostatic factors except alpha 2-PI were within normal range. Both functional and immunological absence of alpha 2-PI were found in the plasma, and this failure to detect alpha 2-PI was not corrected by the addition of the patient's plasma of the first described case of alpha 2-PI deficiency. Clinical and laboratory data revealed that these patients were probably homozygous for alpha 2-PI deficiency and born of heterozygous parents, but not of consanguineous ones. Bleeding episodes due to deficiency of alpha 2-PI in these patients were well controlled by an antifibrinolytic agent, tranexamic acid.

Blood Coagulation Tests↗

Surgery for a chronic cystic hematoma on the right thigh in a hemophiliac A with a potent factor VIII inhibitor.

A surgical case is described of a 40-year-old hemophilia A patient with a potent factor VIII inhibitor (40 Bethesda units) suffering from a chronic cystic haematoma in the right thigh. Surgery was performed after extensive plasmapheresis and administration of a large amount of factor VIII concentrate (42,500 U on the day of operation). During the five post-operative days, the factor VIII level was maintained above 25%, which allowed control of hemorrhage. However, two serious problems, i.e., hemolytic anemia and anamnestic response of factor VIII inhibitor titer, occurred on the 6th post-operative day. The hemolytic anemia was circumvented by administering prothrombin complex concentrate every 8 hours for 12 days until the sutures were removed. There was no bleeding although the inhibitor titer rose to 460 Bethesda units.

Adult↗

Heterogeneity of molecular size of factor VIII/von Willebrand factor in von Willbrand's disease.

Patterns of VIIIR:AG in the plasma and its fractions, cryoprecipitate and cryosupernatant, from various types of von Willebrand's disease (vWd) were observed by SDS 1.5% polyacrylamide gel electrophoresis - cross immunoelectrophoresis (SDS PAGE - CIE). VIIIR:AG in normal cryoprecipitate showed several precipitin peaks which correspond to molecular weights ranging from 8 X 10(5) to 1 X 10(7) daltons and are similar to those in normal plasma. Normal cryosupernatant VIIIR:AG gave smaller molecular weights from 8 X 10(5) to 2 X 10(6) daltons. VIIIR:AG in the plasma and cryoprecipitate from 2 patients with classical vWd gave low precipitin peaks with molecular weights in normal range. VIIIR:AG from 2 patients with subgroup A variant which showed fast anodal migration on the conventional CIE, presented 3 peaks with molecular weight of 8 X 10(5) to 3 X 10(6) which are similar to those in normal cryosupernatant. VIIIR:AG from 2 patients with subgroup B variant which showed normal migration on the CIE, gave normal patterns through all fractions.

Antigens↗

Immunocytochemical localization of neurotensin-containing neurons in the hypothalamus of the Japanese quail, Coturnix coturnix japonica.

The hypothalamus of Japanese quail, Coturnix coturnix japonica, has been studied by means of the peroxidase-antiperoxidase immunocytochemical method, with the use of antibodies to synthetic neurotensin (NT). A number of immunoreactive neuronal perikarya occur in the medial preoptic nucleus of the rostral hypothalamus and a few in the accessory part of paraventricular nucleus and dorsal portion of the infundibular nucleus. Some of them correspond to the parvocellular neurons previously identified tentatively as neurosecretory (Mikami et al. 1975, 1976). Large numbers of immunoreactive neuronal fibers are found in the preoptic area, which extend as a remarkable fiber tract from this area to the ventral septal area and to the subfornical organ. A few immunoreactive fibers also extend ventrocaudally to the infundibular nucleus and to the neural lobe.

Animals↗

Cytological differentiation of the interrenal tissue of the Japanese quail, Coturnix coturnix.

As reported for several other avian species there are clearly distinguishable subcapsular (SCZ) and inner (IZ) zones of interrenal tissue in the Japanese quail. The SCZ contains large columnar cells (type I) with rounded nuclei, polymorphic mitochondria with shelf-like cristae, and relatively small numbers of lipid droplets. The IZ contains two and possibly three types of cells. Type II consists of large columnar cells with moderately dense cytoplasm containing large numbers of lipid droplets and many rounded mitochondria with tubular cristae. Smooth endoplasmic reticulum (SER) and Golgi apparatus are well developed; coated vesicles occur in Golgi area and at the cell surface. Type-III cells occur in IZ and especially in its more peripheral areas. They are columnar cells with strikingly clear cytoplasm (in comparison with type II) containing mitochondria with plate-like cristae and tubular SER. Type-IV cells are sparsely distributed in IZ and occur rarely in SCZ. Type IV may be a degenerating phase of type III. After adenohypophysectomy or section of portal vessels type-I cells atrophy somewhat with a decrease in lipid droplets; type-II cells, also atrophy with conspicuous increase in size and number of lipid droplets, enlargement of mitochondria, and gradual disappearance of Ser; type-III cells decrease in number whereas type-IV cells increase. After injection of ACTH, type-I cells enlarge and their mitochondria, SER and Golgi apparatus become more conspicuous; there is a decrease in lipid droplets in type-II cells and a development of SER, polysomes and Golgi apparatus; there is also a decrease in lipid droplets and a development of SER in type-III cells after injection of 2 IU ACTH and an almost complete disappearance of lipid droplets after 4 IU ACTH; type-IV cells increase in number.

Adrenal Glands↗

Patterns of factor-VIII related antigen on crossed immunoelectrophoresis and large pore polyacrylamide gel-crossed immunoelectrophoresis in von Willebrand's disease.

Plasma samples from patients with various types of von Willebrand's disease were subdivided into six patterns according to the electrophoretic mobility and shape of VIIIR: Ag on crossed immunoelectrophoresis (CIE): pattern 1 no precipitation are, pattern 2 normal mobility with low arc, arc, pattern 3 intermediate mobility with low arc, pattern 4 faster anodal mobility with low arc, pattern 5 normal mobility with normal are height, pattern 6 faster anodal mobility with normal are height. Of 62 patients, 14 had pattern 1, 6 pattern 2, 16 pattern 3, 12 pattern 4, 9 pattern 5, and 5 pattern 6. Large pore polyacrylamide-agarose gel-crossed immunoelectrophoresis (PAAG-CIE) of crude factor VIII fraction from cryoprecipitate revealed no arcs in patients with pattern 1, three arcs of reduced height in the patients with patterns 2 and 3, four arcs very similar to normal control in patients with pattern 5, and two arcs with fast anodal migration in the patients with patterns 4 and 6. Crude factor VIII fractions from normal cryosupernatant showed one low fast anodally migrating arc corresponding to the fourth arc of normal cryoprecipitate. No peak was seen in patients with pattern 1, and one low fast anodal arc similar to normal control was present in the patients with patterns 2, 3, 4, 5 and 6.

Antigens↗