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Biomedical subjects

A Kojima

Publications and source records attributed to A Kojima.

At least 271 records · Page 15Linked to original sources

Experimental autoimmune prostatitis after neonatal thymectomy in the mouse.

Experimental autoimmune prostatitis (EAP) could be induced in (C3H/HeMs X 129/J)F1 mice by thymectomy (Tx) at 3 days (Tx-3) but not at 0 or 7 days after birth. Appearance of EAP was noticed in the three lobes of the prostate, most frequently and severely in the anterior lobe (coagulating gland). EAP thus induced was characterized by a loss of secretory products in the lumen, massive lymphocytic infiltration in the stroma, especially beneath the epithelial cells, and by the presence of circulating autoantibody(ies) against the epithelial cells of the prostate (APA). EAP started at puberty and its incidence was 68% in 50-150 day old mice. APA was completely absorbed with the homogenates of prostate but not of seminal vesicles, testes or livers of the mouse. High titres of APA, detectable in sera of more than 1,000-fold dilutions accompanized with the severe lesion, were assayed by indirect immunofluorescence (IFL) technique. No sign of EAP was seen in the immature prostate of 90 day old mice which were orchidectomized at 0 day (Orx-0) followed by Tx-3. Exogenous androgen treatment at an adult age induced EAP in these Orx-0 plus Tx-3 mice. The findings indicate that mice which received Tx at a critical neonatal age develop EAP by autosensitization to the antigen(s) normally expressing in the differentiated prostate.

Animals↗

Direct preparation of spherically agglomerated salicylic acid crystals during crystallization.

Needle-like salicylic acid crystals were transformed into a spherically shaped dense form during crystallization by the spherical crystallization technique. Agitation of a mixture of ethanol-water-chloroform containing salicylic acid yielded spherically agglomerated salicylic acid crystals. The crystallinity of the agglomerated salicylic acid the amount of ethanol in the solvent mixture was decreased. The wettability of the agglomerated crystals increased when the amount of ethanol in the solvent mixture was decreased, and this enhanced the dissolution rate of the crystals. The remarkable improvements in the flow and packing of the agglomerated crystals enabled the direct compression of the crystals.

Chemical Phenomena↗

Effects of pertussis toxin (PT) on T-cell populations sensitized for delayed-type hypersensitivity in mice.

Effects of pertussis toxin (PT) on sensitized T-cell populations for delayed-type hypersensitivity (DTH) were examined in mice. DTH was induced by sensitizing mice with ovalbumin (OA) and elicited by injecting OA into the footpad. DTH could be conferred on naive recipient mice by injecting sensitized spleen cells either intravenously into mice or locally into the footpad. When the sensitized mice were given PT at the time of DTH-elicitation, they did not express a high DTH reaction, with the maximum reaction 24 hr after elicitation. When the recipient mice were given PT just before intravenous injection of sensitized spleen cells, DTH was not conferred. In addition, when the sensitized spleen cells were treated with PT in vitro and then transferred intravenously, DTH was not conferred in recipient mice. However, DTH was conferred by local transfer of the sensitized spleen cells even after treatment with PT in vitro. Migration experiments using 51Cr-labeled, sensitized splenic T cells demonstrated that PT treatment of the T-cell population inhibited its accumulation in the DTH reaction site 24 hr after intravenous transfer. On the other hand, experiments on in vitro lymphokine production by the sensitized splenic T cells demonstrated that the PT treatment did not inhibit antigen-dependent production of a macrophage activating factor (MAF). These results suggest that PT suppresses the migration of the sensitized T-cell population from the circulation of the DTH reaction site but not their MAF production. Based on these findings, possible mechanisms by which PT affects DTH are discussed.

Adjuvants, Immunologic↗

Development of "granulosa" cell tumors from intrasplenic testicular transplants in castrated ACI rats.

A day-old testis was transplanted into the spleen of one-month-old castrated ACI male rats. For the first six months, diffuse hyperplasia of the interstitial cells was conspicuous with progressive deletion of spermatogenic cells in the seminiferous tubules. Then multiple foci of hyperplastic nodules started to appear, mainly near the tunica albuginea, in all castrated rats, but never in noncastrated rats. These nodular tissues gradually fused together (so-called Leydig cell tumors) and at about 12 months, other distinct tumor foci, morphologically indistinguishable from ovarian granulosa cell tumors, developed in and replaced the nodular tissues. The specific binding of follicle stimulating hormone to the "granulosa" cell tumor tissues was demonstrated. The hypothesis is presented that Sertoli cells were involved in the hyperplastic nodules and ultimately gave rise to the "granulosa" cell tumors.

Animals↗

Effects of pertussis toxin on delayed-type hypersensitivity responses and on the activity of suppressor T cells on the responses.

Experiments were performed on mice to investigate the effects of pertussis toxin (PT) on delayed-type hypersensitivity (DTH) to ovalbumin (OA) and on the activity of suppressor T cells on the DTH (DTH-Ts). Mice immunized with alum-precipitated ovalbumin showed a transient DTH, which was determined as footpad swelling which disappeared 2 weeks after immunization. Maximal footpad swelling was observed 24 hr after DTH elicitation. On the other hand, when mice received PT (2 micrograms/mouse) at the time of immunization, the transient DTH became an enhanced and persistent DTH, which persisted for at least 4 weeks. In addition, the time of maximum footpad swelling was delayed from 24 to 48 hr after DTH elicitation. The immune spleen T cells from PT-treated mice showed a persistently high ability to transfer DTH into syngenic naive mice. DTH-Ts was induced in spleens of mice injected iv with OA-coupled syngeneic spleen cells. However, when these mice received PT at the time of suppressor induction, their spleen cells revealed considerably reduced suppressor activity. The activity of DTH-Ts was also reduced when DTH-Ts were either treated in vitro with PT or transferred into PT-injected recipient mice. From these results, interference with the suppressor function of DTH-Ts from PT was considered to be, at least in part, as an enhancing mechanism of DTH.

Animals↗

Properties of cloned T cells that mediate delayed-type hypersensitivity against ovalbumin in mice.

Cloned T-cell lines that mediate delayed-type hypersensitivity (DTH) against soluble protein antigen, ovalbumin (OA), were established in (C57BL/6 X DBA/2)F1 mice and their properties were examined. They induced antigen-specific delayed-type footpad reactions, characterized histologically by a predominant mononuclear cell infiltration, when transferred intravenously into syngeneic mice. Morphologically, they were medium or large lymphoblasts with granules in the cytoplasm and expressed Lyt 1 cell surface antigens. One of them proliferated antigen specifically under the presence of both C57BL/6 and F1 accessory cells, while others proliferated antigen specifically only under the presence of F1 accessory cells. They also produced macrophage-activating factor (MAF) and substances which mediate a DTH-like footpad inflammatory reaction with a maximum 6 hr after injection into the footpad of normal mice, when incubated in the presence of specific antigen and specific accessory cells in a serum-free medium for 24 hr. These results demonstrate that cloned DTH-effector T cells, established here against soluble protein antigen, are Lyt 1-positive, large lymphoblasts and that they produce MAF and footpad-reactive inflammatory substances antigen specifically under the presence of specific accessory cells.

Animals↗

Genetic susceptibility to testicular autoimmunity: comparison between postthymectomy and postvasectomy models in mice.

The genetic susceptibility was compared in six mouse strains to both postthymectomy (post-Tx) autoimmune orchitis, induced by thymectomy at Day 3, and postvasectomy (post-Vx) autoimmune testicular lesions, induced by bilateral vasectomy with ligation at 2 months of age. Results from mice examined at 4 months of age showed that the strain distribution of the post-Vx testicular lesion was similar to that of post-Tx orchitis. The SWR/J strain was susceptible, the DBA/1J, C57L/J, BALB/cJ and probably C57BL/10J strains were resistant, and the A/J strain was intermediate. Anti-sperm antibodies (IgG) were produced to varying degrees in all strains of vasectomized mice irrespective of the testicular lesion. Neither the development of the testicular lesion nor antibody formation was associated with the particular H-2 haplotypes of mice in either system. Neonatal thymectomy significantly enhanced anti-sperm antibody formation in the post-Vx system and resulted in a mild testicular atrophy in a resistant strain BALB/cBy. All these data suggest that a gene(s) outside the major histocompatibility complex may determine the genetic susceptibility to testicular autoimmunity, possibly at the testicular level.

Animals↗

Hapten-specific help mediated by an anti-ABA T cell line.

Long-term cultures of functional T cells were grown from mice injected with azobenzene arsonate (ABA) coupled spleen cells or mice painted with the diazonium salt of p-phenylarsonate. All cell lines produced delayed hypersensitivity to ABA. When tested for helper function in an antibody-forming cell assay only one line, AA3, helped plaque-forming cell formation. It was able to help anti-FLU response of FLU-HGG primed B cells to ABA-KLH-FLU. The help required linkage of the ABA and FLU determinants because cultures stimulated with a mixture of ABA-KLH and TNP-KLH-FLU did not show increased PFC. These experiments demonstrate hapten-specific help in a system which eliminates involvement of passively absorbed antibody in hapten recognition.

Animals↗

[A double blind clinical trial of cefamandole and cefmetazole in complicated urinary tract infections].

We conducted a randomized double blind comparison of cefamandole (CMD) and cefmetazole (CMZ) in the treatment of 193 patients with complicated urinary tract infections. The patients received 1 gram of CMD or CMZ twice a day intravenously by drip infusion over 1 hour for 5 days. Pretreatment urinary leukocyte counts and urinary bacterial counts were at least 5 cells/hpf and 10(4) bacteria/ml, respectively. Each patient was randomly allocated either to CMD or CMZ group. There were 93 patients in CMD group and 100 patients in CMZ group. Clinical efficacy was evaluated based on the effect of treatment on bacteriuria and pyuria according to the criteria set by the UTI Committee, Japan. The response to CMD treatment was excellent in 18 cases (19.4%), moderate in 38 cases (40.9%) and poor in 37 cases (39.8%) with an overall effectiveness of 60.2%, whereas the response to CMZ was excellent in 19 cases (19.0%), moderate in 40 cases (40.0%) and poor in 41 cases (41.0%) with an overall effectiveness of 59.0%. No statistical significant difference was found between 2 treatment groups. Comparison of the bacteriological response between 2 groups showed that the eradication rate for strains of Gram-positive cocci were significantly higher in those patients treated with CMD. Gram-negative rods were eradicated from 68.4% of cases treated with CMD, and 78.0% of those with CMZ, but the difference was not significant. Adverse reactions were observed in 3 patients receiving CMD 1 case each of diarrhea, eruption and epigastric pain. Abnormality in laboratory tests was found in 6 patients in each treatment group. The results indicate that CMD is effective, safe and useful in the treatment of patients with complicated urinary tract infections, and its efficacy, safety and usefulness are comparable with those of CMZ.

Adolescent↗

[Combination chemotherapy with adriamycin, carboquone and 5-Fu for bladder cancer].

We treated 25 bladder cancer patients with combined cytotoxic chemotherapy of adriamycin (10--20 mg/day administration on days 1, 2 and 3), carboquone (4 mg/day administration on day 1 of weeks 3, 4 and 5 and 5-Fu (200 mg/day for 5 weeks) or futraful suppositories (750 mg/day for 5 weeks) as one course. According to the Koyama - Saitoh criteria, CR + PR was observed in 4 (17.4%) of 23 patients excluding the 2 dropout patients. According to Karnofsky's criteria, an effect with chemotherapy was observed in 9 (39.1%) of the 23 patients. There was a relatively good response rate in a group of 12 patients with the superficial tumors as compared with a group of 11 patients with the deep tumors. There were no severe adverse reactions.

Aged↗

Regulatory mechanism of delayed-type hypersensitivity in mice. IV. Effect of suppressor T cells on the development of memory T cells involved in accelerated generation of DTH-effector cells in vitro.

The effect of suppressor T cells (Ts) on the induction and the subsequent development of memory T cells for delayed-type hypersensitivity (DTH) was examined. The memory cells were induced in the spleens of mice primed previously with a low dose of reduced and alkylated ovalbumin (Ra-OA), and they generated DTH-effector T cells (DTH-Te) in a significantly accelerated fashion when cultured with OA in vitro. Ts were obtained from the spleens of mice which received OA-coupled spleen cells i.v. 4 days previously, and they inhibited antigen-specifically the induction of DTH responses in the recipient mice sensitized with alum-absorbed OA only when transferred with 5 weeks before sensitization. The spleen cells from mice given Ts together with the priming antigen 7 weeks before culture failed to generate DTH-Te in an accelerated manner on restimulation with OA in vitro. The memory cells from primed mice also did not cause accelerated generation of DTH-Te, when cultured with Ts in the presence of OA in vitro. These results indicate that both the induction of the memory cells by priming with antigen in vivo and the subsequent development of memory cells to DTH-Te by restimulation in vitro are inhibited independently by Ts. This corresponded well with the effect of Ts on the development of DTH-memory in vivo.

Animals↗

Regulatory mechanism of delayed-type hypersensitivity in mice. V. Augmentor cells for DTH responses.

Mice primed with 1 microgram of reduced and alkylated ovalbumin (RA-OA) developed not only long-lived memory cells for delayed-type hypersensitivity (DTH), capable of differentiating into DTH-effector T cells (DTH-Te) against ovalbumin (OA) when restimulated in vitro with OA, but also spleen cells capable of augmenting recipients' DTH responses to OA when transferred into cyclophosphamide (CY)-pretreated mice. The augmenting activity in spleen cells, upon transfer, was found 7 days, but not 21 or 91 days, after priming with RA-OA, although memory DTH-Te were present throughout the period of observation. The loss of augmenting activity after day 7 of priming was not due to the presence of suppressor cells; spleen cells taken 21 days after priming failed to suppress, upon transfer, the augmenting activity in 7-day-primed spleen cells as well as induction and expression of DTH responses to OA. When 7-day-primed spleen cells were fractionated on a discontinuous bovine serum albumin density gradient, the augmenting activity was found only in the medium-density-cell layer, although memory DTH-Te were separated in the high-density layer. Augmentation of DTH-Te generation could also be demonstrated in vitro when 7-day-primed spleen cells, but not 21-day-primed spleen cells, were added to cultures of spleen cells from CY-pretreated mice. These results indicate that, in the 7-day-primed spleen, there is an augmentor cell population which is different from memory DTH-Te and interacts with CY-resistant unprimed cells to facilitate DTH-Te generation.

Animals↗

Production by cultured spleen cells of inflammatory substances and other lymphokines that mediate delayed-type hypersensitivity in mice.

In vitro cultivation of normal mouse spleen cells with human serum albumin generated effector cells that mediate the delayed-type hypersensitivity (DTH) reaction. The cultured cells, when incubated in a serum-free medium for a further 24 hr, released substances (FPRF) which caused a footpad inflammatory reaction at a maximum of 6 hr after injection into normal syngeneic or allogeneic strains of mice, as well as macrophage migration inhibition factor (MIF) and macrophage activating factor (MAF). The DTH-effector cells in the culture were fractionated in the low density layers by discontinuous bovine serum albumin density gradient centrifugation. The effector cells in the low density layers were further enriched in the Lyt 1 subpopulation of T cells when fractionated on a fluorescence activated cell sorter. Cells capable of producing the inflammatory substances (FPRF), MIF and MAF were also enriched in the same fraction containing DTH-effector cells. These results suggest that low density, Lyt 1-positive T cells mediating the DTH reaction produce FPRF as well as MIF and MAF.

Animals↗