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Biomedical subjects

S Kotani

Publications and source records attributed to S Kotani.

At least 181 records · Page 10Linked to original sources
PubMed1981

Susceptibility of rats, hamsters, and mice to carious infection by Streptococcus mutans serotype c and d organisms.

Susceptibility of rats, hamsters, and mice to carious infection by S. mutans serotypes c and d was compared. S. mutans serotype c induced a similar level of carious lesions at experimental periods of 68, 82, and 98 d in rats, hamsters, and mice, respectively. On the other hand, S. mutans serotype d developed a high level of caries at those experimental periods in rats and hamsters, whereas in mice it showed weak caries activity.

Animals↗
PubMed1980

Efficient induction of collagen arthritis by the use of a synthetic muramyl dipeptide.

We developed an efficient method for production of experimental polyarthritis. Native collagen (type II) from human costal cartilage was emulsified with incomplete Freund's adjuvant (IFA) containing the synthetic adjuvant N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP), and injected into one hind footpad of the PVG/c rat. This method reproducibly induced severe arthritis with high incidence, whereas the collagen alone in IFA produced mild arthritis with low incidence. MDP alone in IFA was shown to be minimally arthritogenic under identical conditions.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1980

Polyclonal B cell activation by cell wall preparations of gram-positive bacteria. In vitro responses of spleen cells obtained from Balb/c, nu/nu, nu/+, C3H/He, C3H/HeJ and hybrid (DBA/N x Balb/c)F1 mice.

The effects of polyclonal B cell activation (PBA) of cell walls and their cell wall fractions obtained from several kinds of gram-positive bacteria were studied using the anti-sheep red blood cell (SRBC) or anti-trinitrophenylated (TNP) SRBC plaque forming cell (PFC) responses of cultured spleen cells from Balb/c, athymic nu/nu, their littermates (nu/+), C3H/He (LPS-responder), C3H/HeJ (LPS-nonresponder), (CBA/N x Balb/c) F1 male with an X-linked defect in B cell function and the F1 female mice. The cell walls of Staphylococcus epidermidis (ATCC 155), Lactobacillus plantarum (ATCC 8014), Micrococcus lysodeikticus (NCTC 2665), Mycobacterium rhodochrous (ATCC 184), Streptomyces gardneri (ATCC 23911) and Nocardia corynebacteriodes (ATCC 14898) had the ability to induce polyclonal B cell responses in the spleen cells of Balb/c, nu/nu, nu/+, C3H/He and C3H/HeJ mice. The cell wall fractions prepared by enzymatic digestion from the cell walls of S. epidermidis, S. gardneri or N. corynebacteriodes were also capable of inducing polyclonal B cell responses. The responses of spleen cells from (CBA/N x Balb/c) F1 male mice to these active preparations, except the cell walls of M. rhodochrous which possess this ability. The PBA-ability of synthetic peptidoglycan, muramyl dipeptide (N-acetylmuramyl-L-alanyl-D-isoglutamine, MDP), was also examined, and a similar activity was observed in MDP.

Animals↗
PubMed1980

Induction of delayed type hypersensitivity-like skin reaction by peptidoglycans of bacterial cell walls.

Water-soluble glycopeptides isolated from Lactobacillus plantarum and Staphylococcus epidermidis cell walls elicited a delayed type hypersensitivity (DTH)-like skin reaction in rats previously immunized with Mycobacterium tuberculosis cell walls, but not in unimmunized rats. Histological examination of the skin reaction sites in immunized animals revealed a close similarity of this skin reaction to a typical DTH reacton with respect to the time course of development and the types of cells that infiltrated into the skin reaction sites, which were characterized by a predominant infiltration of mononuclear cells at 48 hr. This DTH-like reaction was also demonstrated by immunizing the rats with the cell wall peptidoglycans of L. plantarum or S. epidermidis and skin testing them with homologous as well as heterologous peptidoglycans. The DTH-like reaction appeared to be caused by peptidoglycans that exist in common in the cell walls of phylogenetically distant bacterial species. Furthermore, it was also suggested that the putative antigenic determinants(s) might include both the glycan chain and part of the peptide moieties of the cell wall peptidoglycan rather than either of the single moieties.

Animals↗
PubMed1980

Mitogenic activity of cytoplasmic membranes isolated from L-forms of Staphylococcus aureus.

Cytoplasmic membranes of L-forms of Staphylococcus aureus exerted a strong mitogenic effect on splenocytes of athymic nude mice as well as normal mice, while a cytoplasmic fraction of the same bacteria did not show definite mitogenicity. The mitogenic principle(s) of the membrane fraction was resistant to treatment with trypsin and was heat stable (at 100 C for 10 min). The active principle(s) in the insoluble residue of the membrane fraction digested with trypsin was not extracted with cold acetone, but could be solubilized by extraction with a cold chloroform-methanol mixture (2:1, v/v). The mitogenic principle(s) in the extract was fractionated by silicic acid column chromatography. Among five fractions separated by chromatography, fractions eluted with chloroform-methanol mixtures (1:1 and 1:20, v/v) were found to be strongly mitogenic. The cytoplasmic membranes of the L-forms also exerted a definite mitogenic effect on guinea pig splenocytes, but not on the thymocytes.

Animals↗
PubMed1980

Arthritis-inducing ability of a synthetic adjuvant, N-acetylmuramyl peptides, and bacterial disaccharide peptides related to different oil vehicles and their composition.

A synthetic adjuvant, N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP), failed to produce polyarthritis with a wide dose range in a water-in-oil emulsion of mineral oil such as liquid paraffin, Drakeol, or heavy mineral oil. MDP, however, produced moderate to severe arthritis with almost 100% incidence in a water-in-oil emulsion made up of Difco incomplete adjuvant, which consists of Bavol F as an oil vehicle and Arlacel A as an emulsifier. N-acetylmuramyl-L-alanyl-L-isoglutamine did not produce arthritis, whereas 4,6-diacetyl-MDP produced the disease. Bacterial peptidoglycans, such as disaccharide peptides which were N-acetylglucosaminyl-N-acetylmuramyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelyl-D-alanine and N-acetylglucosaminyl-6,o-acetyl-N-acetylmuramyl-L-alanyl-D-isoglutaminyl-meso-diaminopimelyl-D-alanine, also produced polyarthritis with low incidence in Difco oil but not in the other mineral oils described above. MDP and bacterial disaccharide peptides were able to produce the disease even in the latter mineral oil only when the concentration of Arlacel A was increased from 15% to 20 to 30% in the oil. We concluded that one of the minimal essential structures responsible for development of this disease is MDP, although the role of the oil vehicle remained uncertain, and there is no direct correlation between granulona formation and arthritogenicity of MDP.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1980

Lipophilic derivative of muramyl dipeptide is more active than muramyl dipeptide in priming macrophages to release superoxide anion.

Mouse peritoneal macrophages, when treated with a lipophilic derivative of muramyl dipeptide either in vitro or in vivo by intraperitoneal injection, showed a more than fivefold increase in their ability to generate superoxide anion after stimulation of the macrophages with phorbol myristate acetate. This response was more than twice that observed with the parent molecule, muramyl dipeptide (MDP). Unlike MDP, which has a systemic effect, the lipophilic derivative, [B30]-MDP, did not alter the response of peritoneal macrophages when given subcutaneously in the flank, suggesting that [B30]-MDP remains localized at the site of injection. The enhanced effect of [B30]-MDP over MDP appeared to be due to the inherent lipophilicity of the molecule, and was probably not due to either stimulation of T lymphocytes or activation of the alternative pathway of complement.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1980

Isolation and serotyping of Streptococcus mutans from teeth and feces of children.

Streptococcus mutans were detected in the feces from 10 of 29 caries-active patients, aged 4 to 9 years. The percentage of S. mutans to the total counts of facultatively anaerobic streptococci on mitis salivarius agar (Difco Laboratories) varied from 0 to 72.5%. S. mutans were then isolated from dental plaque of sound teeth and carious dentin of the 10 subjects known to harbor S. mutans in the feces. The frequency distribution of various serotypes of these dental and fecal isolates of S. mutans was compared by the immunodiffusion technique. Of the total 1,047 isolates (290 isolates from feces, 289 from dental plaque, and 468 from carious dentin), type c isolates were most prevalent (ca. 66%). Serotype d, e, f, and g isolates were also found but in far lower frequencies. Plural serotypes of S. mutans were occasionally found in dental and fecal samples of a single subject. For two subjects, relatively rare serotypes of S. mutans in the population examined, serotype e, f, or g, were predominantly found in their fecal and dental samples and those of their siblings and mother, suggesting an intrafamilial transmission of S. mutans.

Child↗
PubMed1980

Isolation and immunobiological classification of Streptococcus sanguis from human tooth surfaces.

A total of 113 pure cultures of Streptococcus sanguis were obtained from dental plaque samples of 64 subjects. All isolates synthesized glucan from sucrose, elaborated peroxide, and were alpha-hemolytic. Two biotypes and four serotypes were differentiated within the species. Biotype A (95 isolates) fermented salicin and inulin and hydrolyzed arginine and esculin, whereas biotype B (18 isolates) did not possess these activities. The isolates were serotyped with autoclaved extracts against whole-cell antiserum to strains ATCC 10556 or ST3 (serotype I), ATCC 10557 (serotype II), ATCC 10558 (serotype III), and ST7 (serotype IV), by the capillary precipitin test. Serotypes I, II, III, and IV were found to consist of 24, 16, 37, and 15 isolates. Type IV was demonstrated anew in this study. The remaining 21 isolates were not typed because of either multiple reactions or nonreactivity against the standardized typing sera. All isolates of serotype II belonged to biotype B, which resembles Streptococcus mitior physiologically. Five isolates representing four serotypes and an untypable strain were examined for their cariogenicity against specific-pathogen-free Sprague-Dawley rats fed high sucrose diet no. 2000. Organisms of each isolate were established in the mouths of the rats, but only three isolates induced weak caries that were restricted to pits and fissures of occlusal surfaces of the teeth.

Adolescent↗
PubMed1980

Liposomes as vehicles for vaccines.

Lipid A from Shigella flexneri LPS, or acylated derivatives of muramyl dipeptide (MDP), were incorporated into the lipid bilayer of liposomes to enhance the adjuvanticity of the liposomes in rabbits. Liposomes containing lipid A induced antibodies against lipid A, phosphocholine, phosphatidylcholine, and sphingomyelin. Lipid A was resolved into eight fractions, some of which did, and others of which did not, induce antibodies against liposomes. Anti-liposome antibodies also were induced (in the absence of liposomes) by complete Freund's adjuvant, and by acid treated bacterial cells coated with lipid A, but were not induced either by lipid A or liposomes alone, or by liposomes containing acylated MDP. We tested the liposomes for the ability to enhance the immunogenicity of a protein antigen. The antigen consisted of liposomes having acylated MDP and ganglioside GM1 (the receptor for cholera toxin, or CT) in the lipid membrane, and CT bound to the outer surface of the liposomes. The liposomal antigen (having surface-bound CT) produced a much greater anti-CT titer than that obtained by injection of CT alone. We conclude that liposomes containing only phosphatidylcholine, cholesterol, and dicetyl phosphate are poorly immunogenic, but that antibodies against them can be induced by inclusion of lipid A. Liposomes that are appropriately formulated can strongly enhance the immunogenicity of a liposome-bound protein antigen.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1980

Further evidence of polyethylene glycol-induced cell fusion of Staphylococcus aureus L-forms.

Further evidence is presented that on treatment with polyethylene glycol the emergence of doubly drug-resistant recombinants of Staphylococcus aureus L-forms from substrains resistant to streptomycin or erythromycin only is really due to cell fusion, and not to other genetic transfer mechanisms. The reason for the necessity of enrichment culture is also discussed.

Drug Resistance, Microbial↗
PubMed1980

Mitogenic effects of bacterial cell walls and their components on murine splenocytes.

Stimulation of splenocytes from ICR mice by cell walls of 17 species of gram-positive bacteria, and peptidoglycans and water-soluble enzymatic digests prepared from some of them, and by synthetic N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) was studied in terms of mitogenic activity. All the cell walls tested except those of Micrococcus lysodeikticus, regardless of their mycolic acid content and immunopotentiating activity, had definite stimulatory activity on splenocytes. In general, the cell walls of mycobacteria, nocardia, and stretomyces had stronger mitogenic activity than other cell walls. The mitogenic activity of cell walls was mainly attributable to a peptidoglycan moiety, and the activity was retained even when the peptidoglycan had been degraded into a monomer or a dimer of its subunit, though a polymerized form of the subunits exhibited stronger activity than the monomer or dimer. Definite mitogenicity of synthetic MDP on splenocytes from ICR mice was also confirmed. The origin of the unknown principle(s) that is found in the cell walls of nocardia, mycobacteria and streptomyces and is responsible for their potent mitogenic activity on murine splenocytes was discussed.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1979

[Diagnostic evaluation on cerebral hemisphere scintigraphy using 99mTc-MAA (author's transl)].

Using 99mTc-labeled macroaggregated albumin (99mTc-MAA), we made an examination of the cerebral blood flow distribution with various kinds of cerebrovascular diseases in 151 cases. The particle size of MAA used in this study ranged from 10 to 100 micron. Scan was performed after injection of 3 mCi of 99mTc-MAA into common carotid artery. No side effects were observed except for one case with headache. Distribution of 99mTc-MAA was found to be homogeneous in normal cerebral hemisphere but not in the lesion. Most lesion was shown as nonradioactive area. Meningioma with hypervascularity was represented as hot area. By this method cerebral infarct could be easily represented not only in main artery but also in such a very small artery as hardly detected by CAG. This method is therefore useful for detecting cerebral infarct, sequela of cerebral apoplexy, head injury and others. The dose of 99mTc-MAA used in this method is much lower compared with those of common brain scan, its excretion is speedy, and therefore internal radiation exposure is diminished.

Adult↗