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M Kawata

Publications and source records attributed to M Kawata.

At least 217 records · Page 12Linked to original sources
PubMed1988

Immunohistochemical demonstration of serotonin-containing nerve fibers in the mammalian hippocampal formation.

The distributional pattern of serotonin-immunoreactive nerve fibers in the hippocampal formation of six different mammalian species (rat, chipmunk, hamster, cat, dog and monkey) was studied in detail by means of a modified peroxidase-antiperoxidase immunohistochemical method, using a specific serotonin antiserum. Furthermore, the density of varicosities distributed in each layer of the hippocampus was semiquantitatively analyzed. In all species investigated, the routes of serotonin fibers entering the hippocampal formation were found to be almost the same. These fibers were extensively distributed throughout the hippocampal formation, and had a characteristic arrangement corresponding to the laminar structure of this region. A dense innervation by varicose serotonin fibers was found in the stratum lacunosum-moleculare, but a few serotonin fibers were also distributed in the stratum lucidum of the CA2 and CA3 fields. The stratum pyramidale and the granule cell layer of the dentate gyrus contained a small number of serotonin fibers. The concentration and the direction of serotonin fibers were different in each area of each animal. Two peculiar observations should be stressed: (1) in the rat, the strata oriens and radiatum of CA2 and CA3 as well as the stratum lacunosum-moleculare displayed abundant serotonin fibers; (2) in the dog, abundant serotonin fibers were diffusely distributed in the CA1 field except for the stratum pyramidale and the most dense concentration of serotonin fibers was seen in the stratum oriens of CA3. The present study provides a morphological basis for further study of the functional significance of serotonin in the limbic system.

Animals↗
PubMed1988

[Placental-site trophoblastic tumor of the uterus--a case report].

A case of placental-site trophoblastic tumor arising in the uterus is reported. The patient, a 34-year-old female, complained of irregular menstruation. Under the diagnosis of a tumor in the uterus or the ovary, a simple total hysterectomy and right adnexectomy were performed. Histologically, the tumor cells, which were large, polygonal or rounded in shape, had infiltrated into the myometrium in clusters or singly. Immunohistochemically, most of the tumor cells were positive to hPL. Further, hCG also was present in some tumor cells, though only weakly. Because of these findings, this case was diagnosed as a placental-site trophoblastic tumor (PSTT).

Adult↗
PubMed1987

Molecular properties of F9 embryoglycan recognized by a unique antibody in sera from patients with germ cell tumors.

Human antibody against an embryoglycan present on a mouse teratocarcinoma cell line F9 was found in sera from 16 of 29 patients with embryonal carcinoma, yolk sac tumor, immature teratoma, and choriocarcinoma of gonadal and extragonadal origins by Farr assay. In contrast, none of the sera from patients (77 cases) with dysgerminoma, seminoma, germinoma, and mature teratoma or from patients (118 cases) with nongerm cell types of ovarian tumors contained this antibody. The antigenic embryoglycan was of high molecular weight (Mr greater than 70,000) on Sephacryl S300 column chromatography and carried binding sites for Grifonia simplicifolia agglutinin-1. The antigenic embryoglycan was also found in F9 cell-cultured medium. Absorption of patients' sera with synthetic Blood Group B trisaccharides failed to remove the antibody against F9 embryoglycan. None of these patients' sera showed higher hemagglutination titer to rabbit erythrocytes than the normal range. In contrast, alpha-galactosyl carbohydrates obtained from Ehrlich ascites tumor cells effectively inhibited the binding of patients' sera with F9 embryoglycan. These results indicate that the human antibody against F9 embryoglycan recognizes alpha-galactosyl structures that are distinct from B blood group antigen, but are cross-reactive with alpha-galactosyl structures on Ehrlich ascites cells.

Animals↗
PubMed1987

Immunohistochemical study of the cells infiltrating human renal allografts by the ABC and the IGSS method using monoclonal antibodies.

Sixty renal allograft tissues obtained from 29 patients were stained with hematoxylin and eosin. These tissues were histologically classified into 4 patterns according to the distribution pattern of the infiltrating cells: normal, focal, focal-diffuse, and diffuse types. Clinical signs of acute rejection were observed in 88% of the patients with the diffuse type infiltration, and 83% of those with the focal-diffuse type infiltration but in only 13% of those with the focal type infiltration. Twenty-four renal allografts were analyzed by the ABC and the IGSS methods using monoclonal antibodies. The number of T cells (Leu 1) accounted for about 80% of the total number of infiltrating cells; 2-8% of the cells were B cells (Leu 12); about 10% were NK/K cells (Leu 7); and 4-6% were monocytes/macrophages (Leu M3). As to helper/inducer T cell (Leu3a) and killer/suppressor T cell (Leu2a), which are T lymphocyte subsets, there were more Leu3a- than Leu2a-positive cells in focal type tissue, but there were more Leu2a- than Leu3a-positive cells in focal-diffuse and diffuse type tissue. In most cases that developed clinical signs of acute rejection, there were more Leu2a- than Leu3a-positive cells. The Leu3a/Leu2a ratio in most of the AZA-administered cases dropped immediately after the transplantation and maintained a low value, but in the CSA-administered cases it decreased gradually post-transplant.

Adolescent↗
PubMed1987

Sensitivity of human germ-cell-tumor cell lines to human interferons.

We examined the sensitivity of four human germ-cell-tumor cell lines exhibiting different stages of differentiation to human interferons (IFNs) in vitro. The cell lines were derived from two embryonal carcinomas (NEC 8 and NEC 14), a choriocarcinoma (IMa), and a yolk-sac tumor (HUOT). Treatment with poly I:C induced IFN production in IMa and HUOT cells, but not in NEC-8 and NEC-14 cells. In the two embryonal-carcinoma cell lines, the addition of IFN-alpha, IFN-beta, and IFN-gamma did not prevent infection by vesicular stomatitis virus and encephalomyocarditis virus. Also, in these two lines, 2-5A synthetase was not induced by the addition of IFN-alpha. In contrast, both IMa and HUOT showed sensitivity to the antiviral action of IFN-alpha and IFN-beta against the two viruses, and 2-5A synthetase was induced by IFN-alpha. IFNs added at doses of up to 1000 IU/ml had no antiproliferative effect on NEC 8, NEC 14, and HUOT, whereas colony formation by IMa cells was greatly suppressed by all three forms of IFN. These results indicate that the production of and sensitivity to IFN are developmentally regulated and are related to the level of differentiation of human germ-cell stem cells.

2',5'-Oligoadenylate Synthetase↗
PubMed1987

prtR enhances the mRNA level of the Bacillus subtilis extracellular proteases.

Studies were performed on the prtR gene which enhances the production of the Bacillus subtilis extracellular proteases and levansucrase, but not the alpha-amylase, RNase, and alkaline phosphatase. To investigate the mode of action of prtR, the Escherichia coli bla gene was placed under the control of two promoters. One was the promoter of the alkaline protease gene (aprE), and the other was the promoter of B. subtilis dihydrofolate reductase gene (dfrA). Expression of the bla gene was enhanced by prtR only when the apr promoter was used. From these results, it was concluded that the apr promoter or its vicinity was the target of prtR and that prtR does not affect the process after transcription. The mRNA levels of aprE and nprE (the neutral protease gene) were significantly increased by prtR, but the half-life of the aprE mRNA was not affected. These results show that the prtR gene product enhances protease production by increasing the rate of transcription initiation.

Bacillus subtilis↗
PubMed1987

Immunohistochemical studies on the distribution of neuropeptides and serotonin in the suprachiasmatic nucleus of the Brattleboro rat.

The distribution of vasoactive intestinal polypeptide (VIP), gastrin-releasing peptide (GRP)/bombesin, somatostatin, vasopressin, neuropeptide Y (NPY) and serotonin was examined immunohistochemically in the suprachiasmatic nucleus (SCN) of male rats genetically deficient for vasopressin (Brattleboro strain). VIP-containing neurons and their varicose fibers were preferentially distributed in large numbers in the ventromedial part of the SCN. GRP/bombesin-containing neurons and their fibers were also gathered in the ventral part of the SCN, particularly in the ventromedial region of the nucleus. Somatostatin-containing neurons and their fibers were prominent in the rostral and middle portions of the SCN, where the highest concentration of immunoreactivity was restricted in their ventromedial part. No vasopressin-immunoreactivity was found at all throughout the SCN. Profuse NPY-containing varicose fibers were observed in the ventrolateral part of the SCN, but no immunoreactive neurons were distributed in this nuclear region. Serotonergic fibers showed a topographic arrangement in the SCN: a serotonin-immunoreactive nerve plexus was predominantly distributed in the ventrolateral part. These findings indicate that the SCN of Brattleboro rats is composed of distinct subdivisions of immunoreactive cell bodies and fibers. The distribution of the five peptides and indoleamine within the SCN in the Brattleboro strain was compared with that in normal Long-Evans rats. Furthermore, both strains of rats were exogenously administered with arginine-vasopressin, but no conspicuous difference in the regional patterns of immunoreactivity was detected. The possible role of vasopressin in the SCN is discussed.

Animals↗
PubMed1987

[The clinical value of sialyl SSEA-1 antigen in patients with gynecologic tumors].

In order to estimate the clinical significance of sialyl SSEA-1 antigen, the antigen was measured with an "FH-6" Otsuka Kit in sera from patients with various gynecologic tumors. Among the patients with uterine malignancies and benign ovarian tumors, the incidence of elevated sialyl SSEA-1 antigen levels was very low. However, among the patients with ovarian malignancies, serum sialyl SSEA-1 antigen was significantly increased in the following order: clinical stage I (40%), stage II (67%) and stage III (75%). The serum antigen values were also correlated with the effect of treatment. In addition, high antigen values were also observed in all 14 malignant ovarian cyst fluids tested. The immunohistochemical localization of sialyl SSEA-1 antigen was determined by an immunoperoxidase method using FH-6 monoclonal antibody. A weak positive reaction was observed in normal glands of female genital tracts. However, the intense staining was shown on the mocus materials or on the luminal surface of some malignant glands as well as in the cytoplasm of some adenocarcinoma cells of gynecologic malignancies, although there were few positive cases or positive cells. Thus, sialyl SSEA-1 antigen appears to be a useful marker in the diagnosis of ovarian malignancies.

Adenocarcinoma↗
PubMed1986

Identification of neuropeptide Y immunoreactivity in the suprachiasmatic nucleus and the lateral geniculate nucleus of some mammals.

The distribution of neuropeptide Y (NPY) immunoreactivity in the suprachiasmatic nucleus (SCN) and the lateral geniculate nucleus (LGN) of 5 kinds of mammals was studied using the peroxidase-anti-peroxidase method. In the SCN of the rat, hamster, chipmunk and cat, NPY-immunoreactive fibers were detected, particularly in the ventral part. In the 3 rodents and the cat, the somata and fibers of NPY-immunoreactive neurons were observed in the LGN. However, immunoreactive structures were not found in the SCN or LGN of the monkey. These results indicate that NPY immunoreactivity in the monkey LGN-SCN tract is absent.

Animals↗
PubMed1986

Cytological features of serotonin-containing neurons and their processes in the retina of the carp (Cyprinus carpio). An immunohistochemical study using flat-mount preparations.

The morphological features of serotonin-containing neurons (SCNs) and their processes in the retina of the carp (Cyprinus carpio) were immunohistochemically studied by applying a modified peroxidase-antiperoxidase technique using flat-mount preparations. The somata of immunoreactive SCNs were mostly located in the innermost part of the inner nuclear layer (INL). These cells were distributed at a density of 64.8 cells/mm2, this being similar to the density of dopamine-containing interplexiform cells. The processes of the SCNs ramified successively into two finer branches, eventually forming a broad, extensive network in the thin layer just subjacent to the plane of the somata of the SCNs. Processes originating from neighboring SCNs exhibited cytoplasmatic continuity with each other at the lightmicroscope level. Due to their location and cytological features, these SCNs appeared to correspond to amacrine cells.

Animals↗
PubMed1986

Simultaneous detection of B-cells and T-cells by a double immunohistochemical technique using immunogold-silver staining and the avidin-biotin-peroxidase complex method.

A new double immunohistochemical technique for the simultaneous detection of B-cells and T-cells was investigated, using tissue preparations obtained from human axillary lymph nodes and rejected renal allografts. The specimens were immunostained first for the demonstration of B-cells, by the immunogold-silver staining (IGSS) method using Leu-12 monoclonal antibody, and then for T-cells by the avidin-biotin-peroxidase complex (ABC) method using Leu-1 monoclonal antibody. With the present methods, both B-cells and T-cells were clearly detected and distinctively identified without cross-linking of antibodies or double reaction of enzymes.

Antibodies, Monoclonal↗
PubMed1986

Pharmacokinetic and pharmacodynamic evaluation of gelatin microcapsule containing piretanide in beagle dogs.

A sustained-release property of gelatin microcapsules of piretanide was evaluated by pharmacodynamic parameters. The gelatin microcapsules of piretanide showed long-lasting, slow-release properties, when compared with its ordinary tablet form in the plasma piretanide level, piretanide excretion rate, urine excretion rate and urinary electrolyte (Na+, K+, Cl-) excretion rate without any loss in diuretic and saluretic activities, which fully satisfied the criteria for a sustained-release preparation.

Administration, Oral↗
PubMed1986

In vivo evaluation of ethyl cellulose microcapsules containing ampicillin using rabbits, beagle dogs and humans.

Ampicillin, an orally administered antibiotic, was microencapsulated with different viscosity grades of ethyl cellulose (10, 50 and 100 cps EC) and was orally administered to rabbits, beagle dogs and humans. A significant sustained release pattern was observed in rabbits. While a significant decrease in the area under the plasma concentration curve occurred, and the sustained release pattern was not obtained in beagle dogs. In humans, the extent of the sustained release was intermediate between the pattern observed in beagle dogs and rabbits. The treatment of data by log-log plots yielded a linear relation between half lives of dissolution of ampicillin from microcapsules in vitro (T50) and the ratios of pharmacokinetic parameters of microcapsules to those of powder. In order to explain the difference in the sustained release pattern of rabbits, beagle dogs and humans, a pharmacokinetic model, considering gastric-emptying and intestinal-transit rates of drug formulations, was established and the pharmacokinetic consideration was done on the basis of the model. It seems that success in sustained release of a drug depended on the magnitude of the gastric-emptying and intestinal-transit rate constant (kgi) of microcapsules, in the case of a drug with a small absorption rate constant (ka) as observed with ampicillin. The magnitude of kgi was thought to be in the order of beagle dogs, humans and finally rabbits.

Administration, Oral↗