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Biomedical subjects

S Kato

Publications and source records attributed to S Kato.

At least 1,261 records · Page 70Linked to original sources
PubMed1989

Targeting chemotherapy for intrahepatic periductal lymphatic invasion by mitomycin C adsorbed to activated charcoal in hepatic hilar bile duct cancer.

A new dosage form of anticancer agent, mitomycin C adsorbed to activated charcoal (MMC-AC), was evaluated in the rabbit model of hepatic hilar bile duct cancer. The model was produced by inoculation of VX2 cells into the wall of the hepatic hilar bile duct. Histologic examination revealed that the mode of spreading of VX2 cells in the model closely resembles that of human bile duct cancer. On the other hand, selective accumulation of MMC-AC into the lymphatic vessels around the intrahepatic bile duct was observed after its injection into the hepatic hilum in rabbits. To assess the anticancer effect, 1 ml of MMC-AC was injected into the bile duct wall near the VX2 tumor. The numbers of lymphatic vessels where necrosis of VX2 cells was observed in one-third or more were 34 of 103 vessels 0.5 cm away from the tumor, 23 of 80 vessels 1.5 cm away, and 9 of 67 vessels 2.5 cm away. We believe that the injection of MMC-AC into the hepatic hilum can be effective adjuvant therapy for hepatic hilar bile duct cancer.

Animals↗
PubMed1989

Total manifestations of amyotrophic lateral sclerosis. ALS in the totally locked-in state.

We report 4 cases of amyotrophic lateral sclerosis (ALS) in the totally locked-in state (TLS); 2 of the cases were autopsied. The clinical and pathological findings of ALS reported previously were essentially included in those studied here. In all cases reported in this paper, the voluntary muscles, including the oculomotor muscles, deteriorated rapidly, resulting in respiratory failure within 1.5 years. Successive observation of the 4 cases confirmed that ontogenetically old motor functions, including oculomotor functions, were preserved in the advanced stage, and that the main lesions in the oculomotor system were supranuclear. The 2 autopsied cases showed widespread pathological lesions other than those of the pyramidal tract and motoneurons commonly seen in ALS. We review these findings, and discuss them from an ontogenetical aspect in terms of the development of motor functions and anatomical myelination, and compare them with clinico-pathological findings of progressive supranuclear palsy (PSP) and anatomical structures of the supranuclear oculomotor system in monkeys.

Adult↗
PubMed1989

Expression of human immunodeficiency virus type 1 (HIV-1) gag antigens on the surface of a cell line persistently infected with HIV-1 that highly expresses HIV-1 antigens.

MT-4 cells persistently infected with human immunodeficiency virus type 1 (HIV-1) (MT-4/HIV-1) were recently isolated (K. Ikuta, C. Morita, M. Nakai, N. Yamamoto, and S. Kato, Japan. J. Cancer Res. (Gann), 79, 418-423, 1988). Mouse hybridoma cell clones producing monoclonal antibodies (MoAbs) to HIV-1 gag p24 and p18, and pol reverse transcriptase (RT) were isolated by using this MT-4/HIV-1 cell line for the screening of MoAb production by the immunofluorescence (IF) test. By indirect IF tests of acetone-fixed cells with these MoAbs, the IF intensities in MT-4/HIV-1 cells were found to be higher than those in the other HIV-1 infected cells, such as MOLT-4/HIV-1, HL-60/HIV-1, and U937/HIV-1 cells. Cell surface expression of the HIV-1 gag p24 and p18 antigens examined by IF and radioimmune techniques with these MoAbs revealed the p24 and p18 antigens to be expressed strongly on the cell surface of MT-4/HIV-1 cells and faintly on the cell surface of MOLT-4/HIV-1 cells, respectively. However, monoclonal antibody isolated in the present study failed to detect pol RT antigen on the surface of MT-4/HIV-1 cells. These results indicate that the gag p24 and p18 antigens are expressed, at least in part, on the surface of HIV-1-infected cells.

Antibodies, Monoclonal↗
PubMed1989

Blockade of ACh receptors by PrBCM causes deficits in shuttle avoidance performance.

Studies were made examining the effect of blockade of muscarinic acetylcholine (mACh) receptors in the cerebral cortex of rats on their shuttle avoidance after training. Rats were given a session of shuttle avoidance tests once a day for 12 days. Then the irreversible antagonist of mACh receptors, propylbenzilylcholine mustard (PrBCM), was injected bilaterally into the cerebral cortex of rats showing avoidance rates of more than 75% in the last session, and avoidance rates were examined 24 hr later. The avoidance rates of the rats treated with 100 micrograms PrBCM were lower than those in the last session before treatment. The amount of mACh receptors in the cerebral cortex was decreased by PrBCM treatment, as shown by [3H]quinuclidinyl benzilate (QNB) binding studies performed just after measurement of the avoidance response. The present study indicates that cholinergic neurotransmission in rat cerebral cortex is involved in performing a learned shuttle avoidance.

Animals↗
PubMed1989

Spontaneous recovery from hypopituitarism due to postpartum hemorrhage.

A rare case is presented of a woman with spontaneous recovery from hypopituitarism following postpartum hemorrhage. One month after delivery, serum thyroid hormone, TSH, LH and FSH levels were low, and their secretion from the pituitary gland responded poorly to the TRH and LH-RH tests. Pituitary TSH response was normal 3 months after delivery. In the LH-RH test, pituitary LH and FSH response returned to normal at 2 months. Pituitary GH secretion and serum cortisol levels induced by ITT already responded normally one month postpartum. Excessive secretion of pituitary PRL was observed 3 months after delivery and improved gradually thereafter. These results indicate that the secretion of pituitary tropic hormones was sensitive to pituitary ischemia in the following order: TSH, gonadotropin, GH and ACTH. The disturbance of these hormones also persisted in the same order.

Adult↗
PubMed1989

Lymphotoxin cDNA clones from a HTLV-I-carrying T cell line HUT-102.

The conditioned medium of a HTLV-I-carrying T cell line HUT-102 showed cytotoxic activity against a mouse fibroblast cell line L-M. We prepared the cDNA library from HUT-102 poly(A)+ RNA and screened it using oligonucleotide probes that correspond to the amino acid sequences conserved in tumor necrosis factor (TNF) and lymphotoxin (LT). As a result we obtained two kinds of cDNA clones encoding LT in which amino acid residue 26t of mature LT is different; one is Asn and another is Thr. The sequence of the genomic clones obtained using a polymerase chain reaction method showed that the HUT-102 genome also contains two types of LT genes. Recombinant LTs expressed in Escherichia coli exhibited the same level of cytolytic activity against L-M cells. These results indicate that the cytotoxin constitutively produced by HUT-102 cells include two kinds of LT.

Amino Acid Sequence↗
PubMed1989

Identification of virus-specific polypeptides by monoclonal antibodies against serotype 2 Marek's disease virus.

A total of 41 antibody-secreting hybridoma cells against the HPRS24 strain of Marek's disease virus (MDV) type 2 (MDV2) have been isolated. Of these monoclonal antibodies (MAbs), 24 were found by immunofluorescence tests to react specifically with MDV2-infected cells, but not MDV type 1 (MDV1)- or herpesvirus of turkeys (HVT)-infected cells, while eight reacted with MDV1- or MDV2-infected cells and nine with MDV1-, MDV2- or HVT-infected cells. By using these MAbs, seven classes of MDV type-specific or cross-reactive polypeptides were characterized by immunoprecipitation followed by SDS-PAGE. Among them, a 28K/32K glycoprotein differed from the previously identified gA and gB. The 28K/32K glycoprotein was found on the surface of MDV2-infected cells and in the cytoplasm by an immunofluorescence test with MAbs. In addition, a cross-reactive polypeptide of 25K/29K was also detected in MDV1-infected cells with MAbs reactive with the 28K/32K glycoprotein of MDV2.

Antibodies, Monoclonal↗
PubMed1989

Tumor cells treated with vaccinia virus can activate the alternative pathway of mouse complement.

Vaccinia virus has been shown to render mouse tumor cells highly immunogenic. Since we have demonstrated that induction of complement activating capacity on guinea pig tumor cells by Sendai virus infection causes the tumor cells to become immunogenic, we assumed that vaccinia virus infection of mouse tumor cells might render them reactive with homologous mouse complement. Therefore, murine tumor cells, MH134 and X5563, infected with vaccinia virus (VV) were incubated with mouse plasma and C3 deposition was determined by staining with fluorescein isothiocyanate-labeled anti-C3. We found that VV-infected tumor cells possess the ability to activate the alternative complement pathway (ACP) of murine complement. For induction of complement activating ability, at least a 3 h incubation of the infected MH134 cells was required indicating that the generation of ACP-activating capacity on MH134 infected with VV is time-dependent. Furthermore, ultraviolet-irradiated vaccinia virus was able to induce ACP-activating capacity on tumor cells as well.

Animals↗
PubMed1989

Induction of peroxidase and thyroglobulin by TSH in cultured thyroid cells from patients with Basedow's disease and its inhibition by actinomycin D.

The effects of TSH on peroxidase activity (PO) and thyroglobulin (TG) production were investigated using primary cultures of thyroid cells obtained from patients with Basedow's disease (Basedow's cells). PO activity of cultured cells and TG concentration in the culture medium were measured by biochemical and sandwich enzyme immunoassays, respectively. The addition of TSH (10 mU/ml/day) to the medium did not increase the cell number but did increase the PO activity and TG concentration. It took more than 3 days for the PO activity of cells cultured with TSH (stimulated group) to reach a level twice that of cells cultured without TSH (control group), whereas 2 days of incubation with TSH was sufficient for increasing the TG concentration. When actinomycin D (AD) was added to the medium on the first day of 3-day incubation with TSH, the stimulatory effect of TSH on PO was completely blocked and the TG concentration was reduced to half that of the control group. AD given to the stimulated group on the last day of induction produced no inhibitory effect on the induction of PO activity by TSH, but reduced the TG concentration to almost half that in the stimulated group. An electron microscopic study of Basedow's cells cultured with AD and TSH failed to reveal any cytopathic change. The findings of the present study suggested that in cultured Basedow's cells TSH induces PO activity and TG production through the synthesis of new messenger RNA.

Cell Count↗
PubMed1989

Serological analysis of cell surface antigens in choriocarcinoma cell lines.

Major histocompatibility complex (MHC) antigens as well as blood group related antigens were investigated in four newly established gestational choriocarcinoma cell lines (NaUCC-1, -2, -3, and -4) using protein A and immune adherence assays. Antibodies to both monomorphic determinants of HLA class I antigens and beta 2 microglobulin reacted with all of the choriocarcinoma cell lines at levels equal to or much greater than SCH, which was teratoid choriocarcinoma cell line. Antibodies to polymorphic determinants not only of the patient's HLA type, but also of the husband's type, reacted to NaUCC-1 and -2. These results indicated that all four newly established choriocarcinoma cell lines express class I HLA antigens. However, we could not demonstrate expression of class II antigens. No expression of blood group A and B antigens could be established, and binding of antibody to Rho(D) antigens was only positive in the NaUCC-1 cell line. These results suggest that some choriocarcinoma cell lines actually express alloantigens and that choriocarcinomas have the character of transplanted tumors that have activities to induce transplantation immunity of the patients.

ABO Blood-Group System↗
PubMed1989

Specific inhibitory substance to the husband's HLA allotype in sera from patients with gestational trophoblastic disease detected by lymphocytotoxicity testing.

The sera of nine patients with gestational trophoblastic disease were investigated for the inhibitory substance specific to the HLA allotypes of the patients' husbands by microcytotoxicity inhibition testing using monoclonal antibodies (anti-A2, A9, A10) and HLA-typing serum to Bw52. The specific inhibitory substance was present in three of three choriocarcinoma patients, in three of four invasive mole patients, and in one of two hydatidiform mole patients and seemed to change in titer parallel with tumor growth. These facts suggest that the inhibitory substance could have some relation to the patient's immunological response against the tumor; that is, this inhibitory substance could be the reason why patients could not induce graft rejection response to trophoblastic tumor cells.

Antibodies, Monoclonal↗
PubMed1989

A plethysmographic technique for direct measurement of airway resistance in hamsters.

We have developed a new technique to directly measure airway resistance (Raw) in small animals with a pressure-type body plethysmograph equipped with a hot-wire microflow sensor. Seventeen male golden hamsters weighing 70-84 g were studied. Change in alveolar pressure (delta PA) was calculated from total gas volume and the respired volume difference through the flow sensor between the midpoints of the tidal excursion curve, reflecting the thorax movement. The ratio of delta PA to the flow difference between those two midpoints gave Raw. Raw was compared with pulmonary resistance, and inspiratory and expiratory resistances were also compared. Raw was 0.44 +/- 0.06 (SE) cmH2O.ml-1.s. Mean of the coefficients of variation of Raw was 19.6 +/- 3.2% (SE). Raw was well correlated with pulmonary resistance (r = 0.93). We demonstrated that Raw could be directly measured in small animals with a hot-wire flow sensor and a plethysmographic technique, and the values were well correlated with previously reported pulmonary resistance.

Airway Resistance↗
PubMed1989

Microvasculature of normal and involuted mouse thymus. Light- and electron-microscopic study.

The spatial arrangement of blood vessels in the thymus of normal and hydrocortisone-injected mice was studied by light and electron microscopy. The thymus is supplied by one thymic artery which branches into arterioles as it enters the parenchyma. These, in turn, feed capillary networks in the cortex and in the medulla. Cortical networks at the periphery of the lobule form loops which return blood to postcapillary venules at the corticomedullary junction and in the medulla. There is no subcapsular venous drainage. The overall distribution of blood vessels in the involuted thymus is essentially the same as in the normal thymus but the pattern becomes irregular and the vessels are tortuous. The endothelium of the postcapillary venules is flat and surrounded by a wide perivascular space containing many lymphocytes. This space is delimited by basal laminae, on the one side by that of the abluminal surface of the venular endothelium, on the other side by that of a thin, sheet-like epithelial layer formed by cytoplasmic processes of reticular cells. The perivascular space is in continuity with the surrounding interstitial space via gaps in its epithelial sheet. It does not form continuous longitudinal channels along the venules, but is interrupted by epithelial trabeculae. There is no obvious difference in structure between the postcapillary venules and their perivascular space of normal and those of involuted thymuses. Lymphocytes are intercalated in the venular endothelium particularly in involuted glands. They are present in the perivascular space and in gaps of the outer epithelial sheet. These findings suggest that the postcapillary venules and the perivascular spaces may function as pathways for the migration of thymic lymphocytes into or out of the blood circulation.

Animals↗
PubMed1989

Increased ciliary beating frequency of nasal mucosa following immunotherapy for allergy.

The present study was designed to elucidate the effect of immunotherapy on the beating frequency of nasal cilia in patients with nasal allergy. Of 40 patients with nasal allergy due to Dermatophagoides farinae, 20 were treated with immunotherapy by the use of D farinae extracts, and 20 control patients were treated with antihistamine tablets. Mucosal pieces were taken from the right inferior turbinate before and 1 year after the initiation of treatment, and the ciliary beating frequency (CBF) was examined by a photoelectric method. The use of antihistamine tablets did not increase CBF even when it relieved the nasal symptoms. Immunotherapy, on the other hand, increased CBF in 66.7% of patients when it alleviated their nasal symptoms. The CBF before immunotherapy of patients who showed an increase CBF after treatment was statistically higher than that of patients who did not.

Adolescent↗
PubMed1989

Mucociliary disease of the middle ear during experimental otitis media with effusion induced by bacterial endotoxin.

Lipopolysaccharide (10 micrograms/mL) derived from Klebsiella pneumoniae was injected into the middle ear of guinea pigs. The animals were killed painlessly on days 1, 3, and 7 after inoculation, and the mucosal samples from two sites within the tympanic cavity, close to the tympanic orifice and distal to the orifice, were examined for ciliary activity and epithelial morphology. At day 1 and day 3 serous effusion was observed and deterioration of ciliary activity and morphologic changes were observed. No effusion was recognized at day 7, when the ciliary activity in the distal mucosa was still diminished and that in the proximal mucosa had recovered to a normal level. Our data have shown that lipopolysaccharide extracted from K pneumoniae can produce otitis media with effusion in laboratory animals, and dysfunction of cilia due to lipopolysaccharide probably is responsible for the accumulation of middle ear effusion. The mucociliary system is indeed an important defense system and failure of such a system, especially in the mucosa close to the tympanic orifice, can cause the buildup of effusions.

Animals↗