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Y Okamura

Publications and source records attributed to Y Okamura.

At least 163 records · Page 9Linked to original sources
PubMed1988

Effects of alpha-galactosidase digestion on lectin staining in human pancreas.

Effects of alpha-galactosidase (from green coffee beans) digestion on lectin staining were examined in formalin-fixed, paraffin-embedded human pancreatic tissues from individuals of blood-group B and AB. Digestion with the enzyme resulted in almost complete loss of Griffonia simplicifolia agglutinin I-B4 (GSAI-B4) staining in the acinar cells with concomitant appearance of Ulex europaeus agglutinin-I(UEA-I) staining in the corresponding cells. In addition, reactivity with soybean agglutinin(SBA) was also imparted by the enzyme digestion in GSAI-B4 positive acinar cells. beta-Galactosidase digestion following alpha-galactosidase digestion neither reduced the reactivity with SBA nor induced the reactivity with Griffonia simplicifolia agglutinin-II(GSA-II) in GSAI-B4 positive cells, while in UEA-I positive cells, both reduction of SBA reactivity and appearance of GSA-II reactivity occurred after simple beta-galactosidase digestion as well as sequential digestion with alpha- and beta-galactosidase. However, when alpha-L-fucosidase digestion procedure was inserted between alpha- and beta-galactosidase digestion, UEA-I staining imparted by alpha-galactosidase digestion was markedly decreased in intensity and GSA-II reactivity was appeared in GSAI-B4 positive acinar cells. Furthermore, after sequential digestion with alpha-galactosidase and fucosidase, reactivity with peanut agglutinin(PNA) was revealed in GSAI-B4 positive acinar cells as well as UEA-I positive cells in secretors. In non-secretors, strong PNA staining was usually observed in the acinar cells throughout the glands without enzyme digestion.(ABSTRACT TRUNCATED AT 250 WORDS)

ABO Blood-Group System↗
PubMed1988

Development of hypothalamic neurons in intraventricular grafts: expression of specific transmitter phenotypes.

The anlages of the medial-basal hypothalamus (MBH), septopreoptic area (POA), Rathke's pouch, and the parietal cortex (CC) of rats (at 12.5, 14.5 and 16.5 days of gestation) were transplanted singly or in combination into the third ventricle of adult female rats, and the development of neurons in the grafts was investigated immunohistochemically with the use of antisera to tyrosine hydroxylase (TH), somatostatin (SRIH), ACTH, methionine enkephalin-Arg6-Gly7-Leu8 (Enk-8), rat corticotropin-releasing factor (rCRF), rat hypothalamic growth hormone-releasing factor (rhGRF), and luteinizing hormone-releasing hormone (LHRH). TH and all the peptides examined except LHRH were detected in distinct neurons in MBH grafts and in cografts of MBH plus Rathke's pouch from 12.5-day-old embryos. SRIH, rCRF, Enk-8, and TH were found in POA grafts from embryos of the same age. Although immunoreactive LHRH was first detected in neurons in POA grafts from 16.5-day-old embryos, it appeared in cografts of POA and MBH from 12.5-day-old embryos. The immunoreactive fibers developed in the grafts expressed the same characteristic behaviors as in intact brain; the fibers containing hormonal substances formed complexes with the vasculature like in the organum vasculosum laminae terminalis (OVLT) or in the median eminence, while the fibers containing neurotropic signals formed fiber networks surrounding other nerve cell bodies as if they synaptically associate. In CC grafts, the neurons contained TH, SRIH, rCRF, or Enk-8, and their axonal processes formed fiber networks. These findings suggest that all the hypothalamic neurons examined are committed by 12.5 days of gestation to develop maintaining transmitter phenotype and target recognition capacity.

Adrenocorticotropic Hormone↗
PubMed1988

The effect of cyclosporin A on the course of Paragonimus miyazakii infection in rats.

The effect of the immunomodulatory fungal metabolite cyclosporin A (CyA) on the course of Paragonimus miyazakii infection in rats was studied. Administration of CyA 15 to 19 days post-infection resulted in a significantly lower recovery rate of worms and cyst formation in the host's lungs than in controls. Administration of CyA -1 to +3 days post-infection enhanced the growth and maturation of P. miyazakii, expressed as weight of worms and the number of worms with eggs in uteri with respect to control values. This study shows that administration of CyA to rats affects the host-parasite relationship, depending on the time of administration of the drug.

Animals↗
PubMed1988

Cytochemical localization of blood group substances in human salivary glands using lectin-gold complexes.

We investigated localization of blood group antigens and their related substances in human labial salivary and submandibular glands by application of a post-embedding cytochemical staining procedure using lectin- or glycoprotein-gold complexes. Surgical tissue was obtained from 10 patients. Blood group-specific lectins, such as Dolichos biflorus agglutinin or Helix pomatia agglutinin (group A-specific), Griffonia simplicifolia agglutinin-I B4 (group B-specific), and Ulex europaeus agglutinin I (group H-specific) could recognize A, B, and H antigens, respectively, only in mature secretory granules (mature SG), which were found preferentially in cells in the late phase of the maturation cycle. In immature secretory granules (immature SG), which were found in cells in the early or middle phase of the maturation cycle, no binding with these lectins was observed. The Golgi complexes and endoplasmic reticula also were not labeled with these lectins. In blood group O and B secretors, blood group antigens were uniformly distributed throughout all the mature SG examined. However, in blood group A secretors, the distribution was heterogeneous, i.e., in some granules only H antigen was demonstrated, whereas in others both A antigens and a small amount of H antigens were detected. Among the blood group-nonspecific lectins, wheat germ agglutinin (WGA) was found to bind more preferentially to immature SG than to mature SG. This was demonstrated irrespective of the blood group and secretor status of the tissue donor, except that in blood group A secretors WGA bound strongly to some mature SG which possessed A antigen. We discuss the significance of cellular and subcellular mosaic distribution of blood group antigens in connection with morphological differences of secretory granules and the maturation cycle of mucous cells.

ABO Blood-Group System↗
PubMed1988

Effects of alpha-L-fucosidase digestion on lectin staining in human pancreas.

We examined the effects of alpha-L-fucosidase digestion on lectin staining in formalin-fixed, paraffin-embedded human pancreatic tissue from individuals of different blood groups. Digestion with the enzyme resulted in apparent diminished intensity of Ulex europaeus agglutinin-I (UEA-I) staining in the acinar cells. In addition to the decreased intensity of UEA-I staining, reactivity with soybean agglutinin (SBA) was increased in the enzyme-susceptible, UEA-I-reactive cells. The intensity of Griffonia simplicifolia agglutinin-II (GSA-II) staining performed after beta-galactosidase digestion in UEA-I-reactive acinar cells was markedly increased by prior treatment with fucosidase. GSA-II staining following sequential digestion with fucosidase and galactosidase was completely abolished by subsequent digestion with beta-N-acetylhexosaminidase. These results therefore substantiate the previous assumption that SBA-reactive D-galactose-(beta 1-3,4)-N-acetyl-D-glucosamine and GSA-II reactive beta-N-acetyl-D-glucosamine imparted following galactosidase digestion represent precursors of H antigen. The present study further demonstrated that intense peanut agglutinin (PNA) staining was imparted after digestion with fucosidase in UEA-I-reactive sites in secretors. In contrast, nonsecretors showed vivid PNA staining that was usually detected throughout the pancreas without prior enzyme digestion. Here, fucosidase digestion had if any little effect on PNA staining. These results suggest that in secretors a terminal trisaccharide, fucosylated D-galactose-(beta 1-3)-N-acetyl-D-galactosamine exhibiting positive PNA reaction after fucosidase digestion, exists in UEA-I-reactive acinar cells. It is assumed that the secretor gene could control the step of final fucosylation of D-galactose-(beta 1-3)-N-acetyl-D-galactosamine in human pancreas.

Adolescent↗
PubMed1988

[A comparison of radioreceptor assay and immunocytochemical staining for estrogen receptor in leiomyoma and myometrium].

Estrogen receptor (ER) content in myoma and myometrium was determined by radioreceptor assay (RRA), and ER staining was performed by immunocytochemical staining, i.e., the peroxidase-antiperoxidase (PAP) method, in uterine samples from eight patients with uterine leiomyoma. ER content in myoma tended to be higher than that in myometrium, but the difference was not significant. The distribution pattern of ER staining was thought to be an important criterion. When the data were compared on the basis of the number of cells in the site where the largest number of positive cells aggregated, the number for myoma was significantly higher than that for myometrium (p less than 0.05). These results suggest that myoma contains more ER positive cells and more efficiently absorbs estrogen than myometrium.

Female↗
PubMed1988

[Pharmacokinetics of N4-behenoyl-1-beta-D-arabinofuranosylcytosine after intraperitoneal administration].

The patients with cartinomatous peritonitis were treated with the intraperitoneal administration (ip) of N4-behenoyl-1-beta-D-arabinofuranosylcytosineine (BH-AC: analogue of Ara-C), and the pharmacokinetics of BH-AC ip was studied. The following results were obtained (1) Immediately after ip administration, the concentration of BH-AC in ascites became as high as 10(6) ng/ml. At 24 hours following BH-AC ip, 10(4) ng/ml of BH-AC was detected in ascites. (2) Immediately after ip administration the concentration of Ara-C derived from BH-AC in ascites became as high as 10(3) ng/ml. At 24 hours, more than 10 ng/ml of Ara-C was detected in the ascites. (3) Ara-U in ascites was detected also soon after BH-AC ip was performed. Accordingly, it is expected that deaminase may be present in ascites. (4) As compared with in ascites, Ara-C in plasma showed very low level (less than 1 ng/ml). These findings indicate that BH-AC is suitable drug for intraperitoneal administration, because BH-AC revealed low peritoneal and high plasma clearances.

Aged↗
PubMed1988

The efficacy of every-other-day administration of gonadotropin-releasing hormone in women with hypothalamic amenorrhea: gonadotropin-releasing hormone treatment can induce clomiphene responsiveness.

The efficacy of every-other-day gonadotropin-releasing hormone administration was investigated in clomiphene-human chorionic gonadotropin (hCG) resistant, anovulatory women with hypogonadotropism or normogonadotropism. One hundred micrograms of gonadotropin-releasing hormone was injected intramuscularly three times a week for four weeks (one course). Ten of 11 hypogonadotropic patients responded to clomiphene or clomiphene-hCG after one to three courses of gonadotropin-releasing hormone treatment. Once the patients were converted to clomiphene responsiveness, ovulatory response continued without additional treatment, and all four patients who desired pregnancy conceived. Among eight normogonadotropic women, four with amenorrhea of one year or less became clomiphene-hCG responders after one or two courses of gonadotropin-releasing hormone treatment. They were subsequently treated with gonadotropin-releasing hormone after every one or two ovulatory cycles. One of the four women who desired to be pregnant conceived. We conclude that intramuscular gonadotropin-releasing hormone treatment is effective in inducing responsiveness to clomiphene, especially in hypogonadotropic anovulatory women. In normogonadotropic women, gonadotropin-releasing hormone treatment may be useful in those who have been amenorrheic for less than a year.

Amenorrhea↗
PubMed1988

[A case report of advanced ovarian cancer with chronic renal dysfunction treated by CDDP i.p].

Reported in this paper is a case of a 56-year-old female patient who was diagnosed as having an ovarian cancer (stage T 4) with a renal dysfunction (CCr 30.5 ml/min). We instilled CDDP intra-peritoneally (CDDP-ip), taking into consideration the peritoneal clearance (CLp.). The administration of sodium thiosulphate also was combined. The low CLp. of this case (299.2 ml/h) made it possible to instill a high dose in the peritoneal cavity and a low dose in the plasma. This method provided enough of anti-tumor effect and kept the renal function safe. We believe that the CLp. is the most important factor in determining the effect and side effects of CDDp-ip.

Cisplatin↗
PubMed1988

[A comparative study of preoperative intra-arterial infusion chemotherapy and transcatheter arterial chemo-embolization in patients with locally advanced breast cancer].

A Comparative study of preoperative intra-arterial infusion chemotherapy (I.A.) and transcatheter arterial chemo-embolization (TAC-E) was carried out on thirty-eight patients with locally advanced breast cancer. The results were as follows. (1) In the primary lesions, there was no difference in response rate between these two treatment modalities. (2) As for side effects, moderate myelosuppression and gastrointestinal disorders were frequently observed in I.A. group. (3) Considerably lower recurrence rate of visceral metastasis was noted in I.A. group, in comparison with the TAC-E group. After TAC-E, however, there was no local recurrence. (4) Five-year cumulative survival rate of I.A. and TAC-E group were 52.3% and 60.7% respectively, without any significant difference between the two groups. These results indicated that both I.A. and TAC-E were effective preoperative treatment for locally advanced breast cancer. Therefore, we should select each treatment modality considering the patient's characteristics.

Breast Neoplasms↗
PubMed1987

[The effect of prolactin on the early embryogenesis of mice in vitro].

It is said the prolactin (PRL) is correlated with fetal lung maturation during late pregnancy. However, there are few reports about PRL during early pregnancy and the period of peri-implantation. Recently, transient hyperprolactinemia at the preovulatory phase or after follicle aspiration for in vitro fertilization has been reported. Nonetheless, the effect of high PRL on the folliculogenesis and the early embryogenesis is still controversial. Moreover, some researchers reported that human fetal umbilical cord sera was good for the development of ova fertilized in vitro. Therefore, we studied the effect of graded concentrations of PRL (10, 30, 100 ng/ml) on the development of embryos fertilized in vivo or in vitro using ddY mice. We concluded that higher PRL levels caused a smaller number of developed embryos, in statistical significance, into blastocysts and hatched blastocysts. In general, embryos fertilized in vivo developed better than those fertilized in vitro.

Animals↗
PubMed1987

Immunogold labeling of blood-group antigens in human salivary glands using monoclonal antibodies and the streptavidin-biotin technique.

We investigated the localization of blood-group antigens A, B, and H in human labial salivary and submandibular glands by applying a postembedding immunogold method using monoclonal antibodies in combination with the streptavidin-biotin bridge technique. The H, A, and B antigens were only detected in mature secretory granules (SGs), which were mainly found in cells in the late phase of the maturation cycle. In immature SGs, which were present in cells in the early or middle phases of the maturation cycle, these antigens were not detected. All other cytoplasmic organelles were not labeled by the monoclonal antibodies used. In blood-group-O secretors, H antigen was present in almost all of the mature SGs. In blood-group-A secretors, the labeling for H antigen exhibited a mosaic-like pattern, i.e. only some of the mature SGs contained H antigen. With respect to the A and B antigens, a similar mosaic-like pattern of staining was observed in blood-group-A and -B secretors, respectively. To the best of our knowledge, this is the first time that the distribution of blood-group antigens A, B, and H in human tissues has been demonstrated at the electron-microscope-level using monoclonal antibodies.

Antibodies, Monoclonal↗
PubMed1987

Immunocytochemistry of human chorionic gonadotropin in human chorionic villi.

The immunocytochemical localization of human chorionic gonadotropin was investigated in chorionic villi from the seventh to twelfth week of gestation. By the light microscopic peroxidase-antiperoxidase technique, positive reactions of human chorionic gonadotropin were found exclusively in the syncytiotrophoblast. Immunoelectron microscopy by means of the protein A-gold technique reveals localization of the immunoreactive gold particles in two kinds of membrane-bound granular inclusions in this cell; one type is granules of 200 to 300 nm in diameter with moderate electron density and the other is large electron-dense bodies of 500 to 1000 nm. The former seems to be Golgi-derived secretory granules that play a role in the release of human chorionic gonadotropin from the syncytiotrophoblast. Although the origin of the latter is still uncertain, a certain amount of this hormone might be stored or treated by lysosomal digestion in the large bodies during these stages.

Antigen-Antibody Reactions↗
PubMed1987

Kinetic differences between Na channels in the egg and in the neurally differentiated blastomere in the tunicate.

In the tunicate embryo, the cleavage can be arrested at any stage by treatment with cytochalasin B, and yet treated blastomeres can express differentiated phenotypes after a certain period of incubation. We took advantage of these large differentiated blastomeres, which were amenable to electrophysiological recordings, to compare Na channels in the egg cell and those in the neurally differentiated blastomere. The macroscopic Na current in the differentiated blastomere showed a marked slow-decaying component in addition to a fast one, whereas in the egg the fast-decaying component was predominant. Both the I-V relationship and the steady-state inactivation curve shifted about 8 mV in the positive direction in the neurally differentiated blastomere compared with those in the egg cell. Furthermore, single-channel current recordings revealed that Na channels reopened more frequently in the differentiated blastomere than in the egg cell. This characteristic of the channel corresponded well to the marked slow-decaying component of the macroscopic current in the differentiated blastomere. The single-channel conductance was similar in both types of cells. We conclude that the neurally differentiated blastomere expresses a Na channel that has properties of inactivation kinetics distinct from those of the egg-type Na channel and that no detectable egg-type channel coexists in the neurally differentiated blastomeres.

Animals↗
PubMed1987

Parathyroid adenoma imaged by gallium-67 citrate. A case report.

A parathyroid adenoma imaged by Ga-67 citrate in a 17-year-old man with primary hyperparathyroidism and a palpable solid tumor in the neck is presented. Although preoperative examination and intraoperative findings suggested a parathyroid carcinoma, histologic studies showed a parathyroid adenoma with predominant chief cell type.

Adenoma↗
PubMed1987

Histochemical reactivity of soybean agglutinin with blood group antigens and their precursor substances in acinar cells of human pancreas.

In human pancreas, soybean agglutinin (SBA) conjugated to horseradish peroxidase reacted with the acinar cells secreting blood group A and/or H antigen, but not with those secreting only B antigen. For detailed histochemical characterization of SBA staining, the effects of treatment with unlabeled lectins and of digestion of certain enzymes on SBA staining were investigated in formalin-fixed, paraffin-embedded pancreatic tissue from individuals of different blood groups. Pre-incubation of sections with unlabeled Dolichos biflorus agglutinin to block A antigen eliminated subsequent SBA staining in the cells secreting A antigen, although failing to induce any effects in those secreting H antigen. In contrast, pre-incubation with unlabeled Ulex europaeus agglutinin-I (UEA-I) to block H antigen abolished SBA staining in cells secreting H antigen but not in those secreting A antigen. Treatment with galactose oxidase yielded the same results as those with unlabeled UEA-I, i.e., SBA reactivity was significantly diminished in cells secreting H antigen but not in those secreting A antigen. Digestion with beta-galactosidase resulted in a slight decrease of SBA staining in the cells secreting H antigen. Accompanying the decrease of SBA staining, reactivity with Griffonia simplicifolia agglutinin-II (GSA-II) appeared for the first time in the enzyme-susceptible, SBA-reactive cells secreting H antigen. Pre-treatment with galactose oxidase abolished this effect of beta-galactosidase. The GSA-II reactivity disclosed by treatment with galactosidase was completely eliminated by digestion with beta-N-acetylhexosaminidase, indicating that GSA-II staining after digestion with galactosidase is due to exposed penultimate beta-N-acetyl-D-glucosamine residues. These results demonstrate that at least two substances react with SBA in acinar cells of human pancreas, one being terminal beta-N-acetyl-D-galactosamine residues of A antigen, and the other being terminal beta-D-galactose-(1----3 or 1----4)-beta-N-acetyl-D-glucosamine dimers in the precursor of blood group H antigen. Such dimers may exist in close proximity to L-fucose residues of H antigen, since unlabeled UEA-I blocked SBA staining.

ABO Blood-Group System↗
PubMed1987

Examination of exchange assay for glucocorticoid receptor.

We examined a method for the measurement of total, activated and non-activated glucocorticoid receptors using sodium-p-hydroxymercuribenzoate (PHMB) and dithiothereitol (DTT) developed by Banerji and Kalimi (1981). Since the concentration of PHMB required for dissociation of the ligand from the receptors varied with the concentration of protein in the reaction mixture and the rate of reassociation of the ligand to the ligand-liberated receptors was sensitive to the concentration of PHMB used, it was necessary to find the minimum concentration of PHMB which was required for complete dissociation of the ligand. When the optimum concentration of PHMB was selected based on the concentration of protein in the cytosol, almost 100% exchange was attained in the non-heated dexamethasone (Dex)-receptor complexes by this method. However when Dex-receptor complexes were heated at 25 degrees C for 30 min, the amount of 3H-Dex reassociated with the glucocorticoid receptors dropped to 60% of that of the non-heated ones. DEAE-cellulose chromatography of the heated sample revealed that approx. 40% of the bound receptors were activated (eluted with 0.05 M KCl) during the heating period. After DEAE cellulose column chromatography of the exchanged 3H-Dex receptor, complexes reassociated with 3H-Dex were observed only in the fraction of unactivated receptor complexes (eluted with 0.2 M KCl). Furthermore, the fraction eluted with 0.05 M KCl in the DEAE cellulose chromatography of liver cytosol bound to unlabelled Dex did not exchange significantly with 3H-Dex with the method used in the present study.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗