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Biomedical subjects

M Kawata

Publications and source records attributed to M Kawata.

At least 271 records · Page 15Linked to original sources
PubMed1983

Immunohistochemical identification of the corticotropin releasing factor (CRF)-containing nerve fibers in the pig hypophysis, with special reference to the relationship between CRF and posterior lobe hormones.

Immunoperoxidase histochemical investigations on pig hypophysis show that CRF immunoreactive nerve terminals are distributed around the blood vessels in the posterior lobe, particularly in its proximal part adjacent to the intermediate lobe. CRF immunoreactive nerve fibers are also seen in the intermediate lobe. The distribution of the CRF-containing nerve in the posterior lobe was found to be similar to that of the vasopressin-containing nerve terminals. The functional significance of the presence of CRF-containing nerve fibers representing a new component of the hypothalamo-hypophyseal neurosecretory system is discussed.

Animals↗
PubMed1983

Immunohistochemical studies on the peptidergic nerve fibers in the pineal organ of the dog.

The distribution of vasopressin-, oxytocin- and LHRH-containing nerve fibers in the pineal organ of the dog was demonstrated by use of the peroxidase-antiperoxidase immunohistochemical technique. These neuropeptide-containing fibers penetrated through the pineal stalk from the brain, mainly from the posterior commissural region, into the pineal organ. The vasopressin fibers were the most prominent in number, oxytocin fibers and LHRH fibers were the least. Most of these fibers were found in the proximal part of the pineal organ, but some of them were also observed in the distal part. These peptidergic fibers were distributed not only in the perivascular spaces but among the parenchymal cells.

Animals↗
PubMed1983

Antibodies to large glycopeptides in sera from patients with ovarian germ cell tumours.

Antibodies reactive with a murine teratocarcinoma cell line (F9) were detected by immunofluorescence staining in sera from patients bearing ovarian germ cell tumour. Immunochemical studies revealed that antibodies binding to the cell surface of F9 cells react with large glycopeptides which are known to be components of F9 antigens defined by murine anti-F9 antibodies. In addition, treatment of F9 cells with retinoic acid, which induces differentiation of embryonal carcinoma cells, distinctly reduced both the ability of these antibodies to stain F9 cells and the biosynthesis of large glycopeptides by the cells. These findings indicate that the large glycopeptides precipitable by the patients' antibodies are differentiation associated antigens on characteristic embryonic cells.

Antibodies, Neoplasm↗
PubMed1983

[A new serological diagnostic method for malignant ovarian tumors of germ cell origin. Detection of antibodies to large glycopeptides isolated from F9 cells].

Whether the presence of antibodies in patients sera to large glycopeptides (LGP) isolated from a murine teratocarcinoma cell line (F9) can be useful in diagnosing malignant ovarian tumors of germ cell origin was examined by Farr's assay. We measured the binding ability to LGP by Farr's assay of human sera from 188 patients with various ovarian tumors and 110 normal volunteers. All of the 9 patients with dysgerminoma showed negative results (less than 200 cpm). Except the cases with dysgerminoma, 9 (64%) of the 14 patients with malignant ovarian tumors of germ cell origin were found positive (more than 200 cpm). Of these 9 positive cases, 4 cases with endodermal sinus tumor (EST), 2 cases with immature teratoma, one each with immature teratoma plus EST, choriocarcinoma, and mature solid teratoma were included. In contrast, all of the sera from benign ovarian tumors (111 cases), other malignant ovarian tumors (54 cases) and normal nonpregnant women (110 cases) were found negative. These result indicated that Farr's assay of anti-LGP antibodies in sera is useful in diagnosing ovarian germ cell tumors.

Adolescent↗
PubMed1982

Immunohistochemical identification of the oxytocin and vasopressin neurons in the hypothalamus of the monkey (Macaca fuscata).

The hypothalamic oxytocin and vasopressin neurons of the monkey, Macaca fuscata, were demonstrated in Golgi-like images by a modified immunoperoxidase method. The magnocellular oxytocin and vasopressin neurons were distributed mainly in the supraoptic and paraventricular nuclei. In addition to these main nuclei, both types of magnocellular neurons were found in the accessory supraoptic nucleus, the periventricular and perifornical areas, the nucleus of the stria terminalis, the lateral hypothalamic area, and the pars interna of the globus pallidus. Magnocellular oxytocin neurons were seen immediately ventral to the anterior commissure, and parvocellular vasopressin neurons were localized in the medial portion of the suprachiasmatic nucleus. The preferential distribution of the oxytocin and vasopressin neurons was recognized not only in the supraoptic and paraventricular nuclei, but also in other areas. In all areas observed, the cytological difference between the oxytocin and vasopressin neurons could be identified. The area of the perikarya of the vasopressin neurons was determined to be larger than that of the oxytocin neurons. Most of the axons of the oxytocin neurons issued from the perikarya, while the axons of the vasopressin neurons originated in most cases from the thick proximal dendrites. These results show that the oxytocin and vasopressin neurons are distributed in areas much broader than has hitherto been assumed, and that these two peptidergic neurons can be definitely differentiated morphologically as well as functionally.

Animals↗
PubMed1982

Immunohistochemical demonstration of the localization of corticotropin releasing factor-containing neurons in the hypothalamus of mammals including primates.

The presence of the CRF-containing neurons in the hypothalamus was investigated in four different species (cats, dogs, pigs, and monkeys) by the peroxidase-antiperoxidase technique using specific antiserum to CRF. In all animals examined, CRF-containing perikarya were found mainly in the paraventricular and supraoptic nuclei, and a small number of the immunoreactive cells were observed in the accessory supraoptic nucleus and the lateral hypothalamic area. The size of the CRF-containing perikarya ranged from 20-35 micron in diameter. These findings suggest that the magnocellular paraventricular and supraoptic nuclei are the center not only of the classical neurosecretory system for the production of the posterior lobe hormones, but also that of the CRF neuronal system.

Animals↗
PubMed1982

Immunohistochemical demonstration of corticotropin releasing factor containing nerve fibers in the median eminence of the rat and monkey.

By means of the peroxidase-antiperoxidase technique, in conjunction with a specific anti-CRF serum, it was shown that a large number of immunoreactive nerve fibers were demonstrable on the capillary loops of the hypophysial portal vessels in the external layer of the median eminence of the rat and monkey, particularly in its medial part. This result confirms the radioimmunological determination of CRF immunoreactivity in the median eminence.

Animals↗
PubMed1982

Immunohistochemical demonstration of serotonin nerve fibers in the cat neurohypophysis.

Distribution of the serotonin nerve fibers in the neurohypophysis of adult cats was demonstrated using the peroxidase-antiperoxidase method. The serotonin nerve fibers were distributed in the internal and external layers of the infundibulum, terminating on the wall of the capillary loops and the outer surface of the external layer. A small number of the fibers scattered about in the posterior lobe penetrated the intercellular spaces in the intermediate lobe.

Animals↗
PubMed1982

Immunohistochemical studies on the processes of serotonin neurons and their ramification in the central nervous system--with regard to the possibility of the existence of Golgi's rete nervosa diffusa.

Using various vertebrates from teleost to macacus, we studied, by the modified PAP method, the serotonin neurons that are distributed mainly in the raphe nuclei area, focussing on their process ramifications, and obtained the following results. 1. The shapes of serotonin neurons were varied. They were multipolar with many long, thick dendrites. In most of the neurons, more than two axons originated either from the stem of a dendrite or from its tip. 2. The axons contained spherical or spindle-shaped varicosities of varied sizes (diameter 0.5-6 micron). On a few occasions, they became large, Herring body-like droplets. 3. The axons were classified into four groups according to the shape and size of the varicosities they contained: stem fibers, A-fibers (tract fibers), B-fibers (branching fibers) and C-fibers (ground fibers). 4. The axon not only branched frequently, but formed a true network by way of frequent anastomosis at the level of B- and C-fibers. Serotonin fibers do not have endings that correspond to telodendrons, but conduct impulses through "en passant" type synapses. 5. A supraependymal plexus is formed over large areas of the ventricular system. This vast network is considered to be formed by the syncytial continuity of axonal reticulum of many serotonin neurons. 6. Serotonin neurons, and probably noradrenaline neurons as well, should be classified as a third type of neuron, which belong to neither the Deiters type nor the Golgi type neuron. Their characteristic feature is the long, reticular axons, and it is highly probable that this neuron system forms the "rete nervosa diffusa" proposed by GOLGI.

Animals↗
PubMed1982

[Studies on marker substances in cell lines derived from various human gynecologic tumors (author's transl)].

In the five kinds of human cultured cells derived from ovarian adenocarcinoma (HOC-21), ovarian malignant teratoma (HOTC 3), carcinoma of the uterine endometrium (HEC-1B), squamous cell carcinoma of the uterine cervix (SKG-1) and choriocarcinoma (BeWo), the intracellular presence of lactic dehydrogenase (LDH), alkaline phosphatase (AlP), human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP) and plasminogen activator were investigated. The results were as follows. 1) BeWo-, HOC-21-and HOTC 3-cells revealed high activity of intracellular presence of lactic dehydrogenase (LDH), alkaline phosphatase (AlP), human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP) and plasminogen activator were investigated. The results were as follows. 1) BeWo-, HOC-21-and HOTC 3-cells revealed high activity of intracellular LDH in this order, however none of HEC-1B-and SKG-1-cells did. 2) The activity of intracellular AlP was higher in BeWo-cells than in HOC-21-cells. The isozymes of AlP detected in these cells were found to be heat-stable. The others revealed no activity of AlP. 3) The presence of HCG-beta was confirmed in both BeWo- and HOTC 3-cells. The intracellular levels of HCG-beta were found to be higher in BeWo- cells than in HOTC 3-cells. HCG-beta was observed to leak into culture medium not from HOTC 3-cells but from BeWo-cells. It was not detected in the other cultured cells. 4) No AFP was detected in any of these five cultured cells. 5) Plasminogen activator was detected in HOC-21, HEC-1B-and SKG-1-cells in contrast to HOTC 3-and BeWo-cells which were negative for plasminogen activator. These results suggest that the various marker substances detected in the human cultured cells originated from various carcinomas of sexual organs may reflect biological functions of these tumor cells and, furthermore, can apply as tumor markers to the clinical diagnosis of the diseases.

Adenocarcinoma↗
PubMed1981

Methionyl-tRNA synthetase-induced conformational change of Escherichia coli tRNAfMet.

Ribonuclease T2, nuclease S1, and snake venom phosphodiesterase were used as a structural probe for investigation of the interaction between Escherichia coli tRNAfMet and methionyl-tRNA synthetase, and the cleavage sites were analyzed by a rapid sequencing gel electrophoresis of 5'-32P-labeled tRNA. Both endonucleases cleaved the D-loop of synthetase-bound tRNA much more extensively than that of the free tRNA. Positions of A14, G15, A22, and G23 in the D-loop and C35 in the anticodon of the synthetase-bound tRNA were more susceptible to RNase T2. The synthetase-bound tRNA was predominantly cleaved by nuclease S1 at position of G15, G19, G20, and G23 in the D-loop and G2 in the acceptor stem. In contrast, the synthetase-bound tRNA was more resistant to the 3'-exonuclease, snake venom phosphodiesterase, than was the free tRNA molecule. These results suggest conformational change of the tRNA by the synthetase binding which weakened tertiary interaction between the D-loop and T psi C-loop/extra-loop. Production of acid-soluble radioactivity was also examined in the limited digestion of 5'-32P-labeled tRNA or 3'-14C-labeled methionyl-tRNA. The synthetase enhanced the release of acid-soluble oligonucleotides from the 5'-end of the tRNA but suppressed that from the 3'-end of the molecule. These results are consistent with that obtained by gel electrophoresis.

Amino Acyl-tRNA Synthetases↗
PubMed1980

Isolation and some properties of two fragments with inhibitory activity obtained from adzuki bean proteinase inhibitor by peptic digestion.

Proteinase inhibitor II' from adzuki beans was subjected to peptic digestion. One of the resulting fragments, which inhibited chymotrypsin but not trypsin, was composed of 27 amino acid residues. The fragment was confirmed to be derived from the chymotrypsin-inhibitory domain of the original inhibitor. Another fragment, which inhibited trypsin only, contained 38 amino acid residues and consisted of two peptide chains. One of them, consisting of 25 amino acid residues, corresponded to the original reactive site region for trypsin. These fragments were also obtained from inhibitor II by peptic digestion. These findings, confirm that these inhibitors, which do not inhibit chymotrypsin and trypsin simultaneously, have separate and independent domains for the inhibition of each enzyme. The active fragments are homologous in chemical structures with the two fragments from soybean Bowman-Birk proteinase inhibitor. However, unlike the fragments from Bowman-Birk inhibitor, our chymotrypsin-inhibitory fragment was a potent inhibitor of the enzyme and was as resistant as the intact inhibitor to the attack of excess chymotrypsin. The trypsin-inhibitory fragment had a lower anti-tryptic action than the original inhibitor and was gradually inactivated by trypsin. These differences between our fragments and those of the Bowman-Birk inhibitor are probably a result of the replacement of a few amino acid residues in the reactive site regions.

Amino Acid Sequence↗
PubMed1980

Analysis of cell surface antigen on neoplastic lymphocytes by the use of anti-human brain serum.

Cell surface antigens on neoplastic lymphoid cells of T cell lineage were analyzed with a fluorescence-activated cell sorter (FACS-II) by utilizing rabbit antisera raised against human brain tissue (anti-Br) and fetal thymocytes (anti-Ty). Both before and after extensive absorption with normal peripheral blood lymphocytes (PBL), the anti-Br antiserum was capable of staining neoplastic lymphoid cells from patients with Sézary syndrome, mycosis fungoides, thymoma, and chronic lymphocytic leukemia. The absorption of anti-Ty with normal PBL, however, resulted in loss of the ability to stain normal bone marrow cells and preabsorbed with normal PBL was found to stain normal bone marrow cells and neoplastic myeloid cells but not fetal thymocytes. It is suggested that the absorbed anti-Br is capable of detecting differentiation antigens present on immature hematopoietic cells in the bone marrow, which would be anomalously expressed on neoplastic lymphoid cells to T cell lineage.

Adolescent↗
PubMed1979

Immunological abnormalities of aging: an analysis of T lymphocyte subpopulations of Werner's syndrome.

Two T lymphocyte-specific antisera, i.e. naturally-occurring auto-antibody to T cells of systemic lupus erythematosus patients (natural T cell toxic autoantibody) and heterologous antiserum against human brain tissue (antibrain-associated T-cell antigen), were used to detect cell surface antigens of human peripheral T lymphocytes. Nylon column-purified T cells from normal aged individuals and patients with Werner's syndrome (a premature aging syndrome) were reacted with these auto- and heterologous antibodies followed by staining with appropriate fluorescence reagents. The cells were subjected to the automated analysis with fluorescence-activated cell sorter. Fluorescence profiles to T cells of both aged individuals of over 90 yr and Werner's syndrome showed a very similar pattern, with a drastic decrease in the population that had high fluorescence intensity stained with either antiserum accompanied by the relative increase in the cell population that had low fluorescence intensity. Natural T cell toxic autoantibody comparable to that detected in systemic lupus erythematosus patients was found in the serum of six out of seven patients with Werner's syndrome, whereas normal aged individuals produced no such an autoantibody. The results suggest that Werner's syndrome has a change in the lymphocyte population very similar to old individuals, and that such a change is caused by the production of autoantibodies reactive to T lymphocytes.

Adolescent↗
PubMed1979

Histological and cytological studies on the liquor contacting peptidergic neurons in the preoptic nucleus of the Japanese eel (Anguilla japonica).

Liquor contacting peptidergic neurons (LCPNs) in the preoptic nucleus of the Japanese eel (Anguilla japonica), are investigated submacroscopically, light microscopically, electron microscopically (transmission and scanning) and histochemically. LCPNs appear in 8--13 per cent of all neurons constituting the preoptic nucleus and their cytoplasm contains many secretory granules stained by aldehyde-thionin or chrome hematoxylin. LCPNs have an epithelial cell-like polarity and their cytoplasmic organella shift to the supranuclear region. LCPNs are classified into three types (A, B, C) according to the liquor contacting portion of the cell: Granular type A neuron (40--50 x 40--50 microns 2), the cell of which is in contact with the cerebrospinal fluid (CSF), is the most common type and distributed in the ventral portion of the preoptic nucleus; this neuron is not connected with the neighboring ependymal cells by tight junctions. Bipolar type B neuron (60 x 30 micron 2), contacts the CSF with the tip of it cell process and is scattered throughout the preoptic nucleus; the cell is connected with the surrounding ependymal cells by tight junction. Bipolar type C neuron (60 x 30 micron 2) possesses a cell process protruded into the third ventricle and is distributed in the dorsal portion of the preoptic nucleus; this also is connected with the adjacent ependymal cells by tight junction. Regardless of type, all LCPNs exhibit a positive acetylcholinesterase and a negative ATPase reaction. Numerous fluorescent varicosities of monoaminergic nerve terminals are closely associated with the cell bodies of the LCPN. LCPNs are likely regulated by monoaminergic fibers.

Acetylcholinesterase↗