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S Niwayama

Publications and source records attributed to S Niwayama.

At least 37 records · Page 2Linked to original sources
PubMed1988

Relation of H-2 expression on murine RCT(+) sarcoma cells to lung colonization and sensitivity to NK cells.

Murine RCT(+) sarcoma cells were sorted using a fluorescence-activated cell sorter with regard to the expression of H-2 antigens and then an increased H-2-expressing subclone was established, and named RCT(+)H-2+. The experimental metastasis of RCT(+) cells was compared with that of RCT(+)H-2+ cells by counting pulmonary colonies on the 21st day after i.v. inoculation of tumor cells (5-10 x 10(4)/mouse). When mice were inoculated with RCT(+) cells, mean numbers of pulmonary colonies were 2.1(range 0-6), 2.8(range 0-7) using 5 x 10(4) and 1 x 10(5) cells, respectively. On the other hand, in the mice inoculated with RCT(+)H-2+ cells, figures obtained were 7.0(range 4-16), 31.9(range 13-79), using 5 x 10(4) and 1 x 10(5) cells, respectively. The survival rate of RCT(+)H-2+ cells was higher than that of RCT(+) cells, when this was assayed in the early stage after i.v. injection of 51Cr-labeled cells (1 x 10(5) cells/mouse). In addition, RCT(+)H-2+ cells were more resistant than RCT(+) cells to lysis mediated by natural killer cells. These data suggest that an increase in metastatic ability was paralleled by an increase in the H-2 antigen expression and a decrease in sensitivity to the natural killer cells.

Animals↗
PubMed1988

In vitro and in vivo antiviral activity of scopadulcic acid B from Scoparia dulcis, Scrophulariaceae, against herpes simplex virus type 1.

The antiviral activity of five diterpenoids isolated from Scoparia dulcis L., Scrophulariaceae, was examined in vitro against herpes simplex virus type 1. Among these compounds, only scopadulcic acid B was found to inhibit the viral replication with the in vitro therapeutic index of 16.7. The action of scopadulcic acid B was not due to a direct virucidal effect or inhibition of virus attachment to host cells. Single-cycle replication experiments indicated that the compound interfered with considerably early events of virus growth. The influence of scopadulcic acid B on the course of the primary corneal herpes simplex virus infection was investigated by means of a hamster test model. When the treatment was initiated immediately after virus inoculation, scopadulcic acid B, when applied orally or intraperitoneally, effectively prolonged both the appearance of herpetic lesions and the survival time at the dose of 100 and 200 mg/kg per day.

Animals↗
PubMed1988

Antibody-mediated growth of influenza A NWS virus in macrophagelike cell line P388D1.

We investigated the internalization and growth of influenza A NWS virus in macrophagelike P388D1 cells. Flow cytometric analysis using fluorescein isothiocyanate-labeled virus showed that the attachment of normal rabbit serum-exposed virus (NS-V) to neuraminidase (NA)-treated cells was noticeably limited compared with that to untreated cells. However, rabbit antiserum-exposed virus (AS-V) could attach equally well to both cells. Virus coated with Fab prepared from antiviral immunoglobulin G could not attach. These data suggest that the NWS virus can infect P388D1 cells in one of two ways, via viral or via Fc receptors, depending on the presence of antibodies. The NS-V could grow in the untreated cells, but not in the NA-treated cells. The highest growth of AS-V in the NA-treated cells was observed at an antibody concentration showing 50% plaque reduction titer. Growth was exponentially decreased toward the lower and higher dilutions of antibodies. By using three different immunoglobulin G subclasses of monoclonal antibodies against hemagglutinin, it was demonstrated that both Fc receptors I and II could take part in this phenomenon. The presence of 20 mM NH4Cl inhibited the growth of both AS-V and NS-V, suggesting that the intracellular pathways after internalization via Fc or viral receptors are similar. These data indicate that the concentration of antibodies has a critical role on the antibody-mediated growth of influenza virus in macrophages.

Ammonium Chloride↗
PubMed1988

[Inhibition of pulmonary metastases in mice by beta-cyclodextrin-benzaldehyde].

The effect of beta-cyclodextrin-benzaldehyde (CDBA) on the pulmonary metastasis in C3H/He mice was examined. When mice were treated daily with CDBA, 3 weeks later the number of lung nodules developed after i.v. inoculation of 1 X 10(6) RCT (+) cells was significantly decreased. The mean numbers of the lung nodules were 69.9 and 73.4 in the water-and cyclodextrin (CD)-treated mice, respectively. However, these were 17.8, 9.8 and 2.9 in 0.5, 5 and 25 mg/mouse per day CDBA-treated mice, respectively. And also, daily treatment of CDBA prolonged the survival time of the tumor bearing mice in both experimental and spontaneous metastasis studies. Two or three weeks after subcutaneous inoculation of RCT (+) cells (1 X 10(6) cells) to the foot pad, left hindlimbs were amputated and then mice were daily treated or untreated with CDBA. Five weeks after tumor inoculation, the number of lung nodules was counted. Twenty eight point six and 100% of untreated mice had lung metastases when amputation was carried out 2 (earlier operation group) and 3 (latero peration group) weeks after tumor inoculation. However, in CDBA-treated mice, these values were noticeably decreased, that is, 6.7% and 60% in earlier and later operation groups, respectively. Furthermore, in the later operation group, mean number of the lung nodules in CDBA-treated mice was only 2.7 while this was 12.9 in untreated mice. These data suggest that CDBA improve the survival time of tumor bearing mice through the inhibition of the lung metastasis.

Administration, Oral↗
PubMed1987

Single radial complement fixation test using NP-containing plates: a simple and sensitive method for the detection of influenza infection.

The single radial complement fixation (SRCF) test using nucleoprotein (NP) was compared with the haemagglutination inhibition (HAI) test in the course of the evaluation of the protective efficacy of influenza vaccine. In the case of persons who were not vaccinated, the percent incidence of infection was almost the same (which confirmed by HAI test or by SRCF test), whereas in the case of vaccinees, there was a significant difference between the incidence confirmed by HAI (7.9%) and SRCF (19.4%) tests. The SRCF test was shown to be a simple and sensitive method for detection of a significant rise in antibody titre against influenza virus.

Antibodies, Viral↗
PubMed1987

Inhibition of experimental and spontaneous pulmonary metastasis of murine RCT (+) sarcoma by beta-cyclodextrin-benzaldehyde.

The effect of beta-cyclodextrin-benzaldehyde (CDBA) on pulmonary metastasis in C3H/He mice was examined. In experimental metastasis that was induced by iv injection of 1 X 10(6) RCT (+) cells, the highest inhibition was observed in the mice that were treated daily with CDBA (5 mg/day) for 1 week before tumor cell inoculation and further treated for 3 weeks after inoculation, when compared with those in other experimental groups that were given only pretreatment or posttreatment. The inhibitory effect was dose-dependent. In spontaneous metastasis that was induced by sc injection of 3 X 10(6) RCT (+) cells, the inhibition of metastasis was also observed in the mice treated with CDBA (5 mg/day) in the same manner as described above. However, the development of the primary tumor was not inhibited. CDBA-treated tumor-bearing mice showed almost as much NK activity as normal mice. Furthermore, although injection of 5-fluorouracil suppressed this activity to about 50% of that in normal mice, the combined treatment with CDBA could maintain the NK cell activity at the normal level. The results suggested that the inhibition of pulmonary metastasis might be induced by a combined effect of CDBA; that is, the direct inhibition of tumors and the maintenance of NK cell activity.

Animals↗
PubMed1986

Inhibition of experimental pulmonary metastasis in mice by beta-cyclodextrin-benzaldehyde.

The effect of beta-cyclodextrin-benzaldehyde (CDBA) on experimental pulmonary metastasis in C3H/He mice was examined. In an in vitro assay, the growth of RCT(+) cells was inhibited by 1200 micrograms/ml CDBA using unrenewed media, and by 600 micrograms/ml CDBA in that using daily renewed media. When mice were treated daily with CDBA, 3 weeks later the number of lung nodules developing after i.v. injection of 1 X 10(6) RCT(+) cells was significantly decreased in a dose-dependent manner, i.e., 73.8%, 85.6%, and 95.7% inhibition was observed following 0.5, 5, and 25 mg CDBA/mouse per day p.o. administration, respectively. The same mice showed almost as much natural killer (NK) activity as normal mice. Therefore, experiments were designed to evaluate the effect of CDBA on the NK activity of tumor-free mice whose immunity had been suppressed by 5-fluorouracil (5FU). Injections of 5FU only suppressed this activity to about 50% of normal mice, but the combined treatment with CDBA negated the suppressive effect of 5FU on NK activity. The results suggested that the inhibition of experimental pulmonary metastasis might be induced by the possible combined effects of CDBA; that is, the direct inhibition of tumors and the augmentation of NK cell activity.

Animals↗
PubMed1986

Evaluation of the efficacy of split-product trivalent A(H1N1), A(H3N2), and B influenza vaccines: reactogenicity, immunogenicity and persistence of antibodies following two doses of vaccines.

The reactogenicity and immunogenicity of Tween-ether split trivalent A(H1N1), A(H3N2), and B influenza vaccine in primary school children aged seven to 12 years, and the persistence of antibodies following two doses of vaccine were studied during 1980-1984. Adverse reactions were infrequent, and, even when reported, were chiefly local ones, mild in nature and of short duration. Most of the reactions were less frequent after the second dose than after the first dose. Most of the systemic reactions occurred during the intervaccination period with almost equal frequency, indicating that careful consideration is required to judge whether they were induced by vaccination or not. This vaccine had induced adequate hemagglutination inhibiting (HAI) antibody because the geometric mean titers (GMTs) of the vaccinees were two- to eightfold higher than those of the nonvaccinees to any of the vaccine antigens following two doses of vaccine. In general, the responses to A(H3N2) virus were the best among the vaccine antigens through the four vaccination seasons, but there was a tendency to show a poorer response to the same type (or subtype) of virus antigen as the causative one during a protracted epidemic. The antibodies induced by either vaccination or natural infection were shown to persist for less than a year, supporting the recommendation for annual vaccination.

Antibodies, Viral↗
PubMed1986

Evaluation of the efficacy of split-product trivalent A(H1N1), A(H3N2), and B influenza vaccines: protective efficacy.

A total of 1,995 primary school children (1,464 vaccinees and 531 non-vaccinees) were studied to evaluate the protective efficacy of Tween-ether split trivalent A(H1N1), A(H3N2), and B influenza vaccines by comparison of the incidence of confirmed infection in two groups during 1980 to 1984. During the study period, epidemics caused by antigenically different influenza viruses, that is A(H1N1) epidemics in 1981 and 1984, a B epidemic in 1982 and an A(H3N2) epidemic in 1983, were experienced, and at the same time strains changed by antigenic drift were frequently isolated. In these epidemics, 61% to 87% of the children reported respiratory illnesses and 18% to 48% of the illnesses were influenza confirmed by seroconversion. Throughout these four epidemics, the incidence of confirmed infection among the vaccinees (7.8% to 33.8%) was 6.5% to 34.8% lower than that among the nonvaccinees (35.4% to 51.6%), demonstrating that the vaccine was effective (X2 = 76.34, P less than 0.001). However, this effectiveness was not seen in an epidemic in one of the entrant schools in 1984, possibly caused by a strain with intense antigenic drift. On the basis of data on incidence of various symptoms, duration of fever and the number of days of absence from class, it was considered that clinical symptoms in the vaccinees were milder than those in the nonvaccinees. When the titers of hemagglutination-inhibiting (HAI) antibody against the vaccine strains were measured, the protective level of HAI antibody giving less than or equal to 50% incidence of infection was 1:64, but it increased to 1:256 in the 1984 epidemic, reflecting the high rate of isolates with intense antigenic drift.

Child↗
PubMed1981

Study on the single radial complement fixation (SRC-fix) test.

We examined whether the single radial complement fixation (SRC-fix) test is applicable to serological diagnosis of viruses. The viruses used for the examination were influenza A and herpes simplex viruses. SRC-fix test was shown to be a very simple method, that is, serum samples were added to agarose plate A containing complement and CF antigen, and agarose plate B, containing antibody-coated erythrocytes, was layered on top of the plate A to form zone areas of unlysed cells. CF titres of the samples were determined from the square of the zone diameter of unlysed cells. Thus SRC-fix test is suggested as a new method for diagnosis of viral diseases.

Antibodies, Viral↗
PubMed1976

[A case of psittacosis treated with rifampicin (author's transl)].

A 45-year-old male who had looked over pet-birds at a bird shop 11 days before, developed a high fever with chills. Without any response to cephalexin, he was admitted to the hospital, with the chief complaints of high fever and sever headache on the 8th day of illness. The chest X-ray films taken then revealed a fun-shaped ground glass-like shadow extending over S10 of the right lung. After the oral administration of 450 mg rifampicin on the 9th day of illness, he became a febrile within one day and was cured with the same daily doses for the following 10 days. Chlamydia was isolated from the peritoneal exudate of the mice inoculated with throat mucus of the patient taken prior to the administration of rifampicin. Complement fixation reaction for psittacosis was positive in a titer of 1 : 16 on the 11th day of illness and rose to 1 : 64 in a week.

Animals↗