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Biomedical subjects

T Umemoto

Publications and source records attributed to T Umemoto.

At least 109 records · Page 6Linked to original sources
PubMed1989

Subgingival administration of tetracycline on a collagen film.

The purpose of this study was to evaluate the duration of therapeutic effect after administration of the collagen film immobilized tetracycline (TC film). TC film or tetracycline non-immobilized placebo film was applied one time to the periodontal pocket (greater than or equal to 4 mm) of five periodontitis patients (20 teeth). The clinical and microbiological effects are summarized as follows: The group that received TC film continued to show significantly low values for bleeding upon probing the pocket depth for 3 and 4 weeks, respectively, after administration, but there was no significant difference in the plaque index or gingival index when compared with the group that received a placebo film. In the TC film group, the density of microorganisms and the proportion of motile rods and spirochetes were also significantly decreased 3 weeks after administration. These findings suggest that topically administered TC film remains both clinically and bacteriologically effective for 2 to 3 weeks.

Administration, Topical↗
PubMed1989

Application of a local drug delivery system to periodontal therapy: I. Development of collagen preparations with immobilized tetracycline.

For the purpose of applying a local drug delivery system to periodontal therapy, atelocollagen preparations with immobilized tetracycline (TC) were prepared by modifying the form of the collagen, the concentration of the immobilized TC, and the time of the cross-link process with glutaraldehyde. The course of the TC release from the collagen preparations into an aqueous solution was determined in relation to time. The preparations were also inserted into periodontal pockets, and the amount of TC remaining in the pocket was determined daily. The results obtained were as follows: 1) The degree of drug release could be controlled to some extent by adjusting the TC concentration and the time of the cross-link process; and 2) an amount of TC exceeding the effective dose in the gingival crevicular fluid was present in the periodontal pocket even 10 days after the insertion of TC fixed in the cross-linked processed collagen film in the periodontal pockets.

Bacteria↗
PubMed1989

[Application of local drug delivery system to periodontal therapy. 4. Comparison of the therapeutic effects of administration of a TC film or root debridement on human periodontal disease].

In 8 patients with periodontal diseases under good supragingival plaque control, 22 test teeth each having a pocket not more than 4 mm deep were treated respectively with 3 consecutive administrations of tetracycline immobilized cross-linked collagen film (TC film) at intervals of 1 week, with onceroot planing and with both of these. The therapeutic effects were compared both clinically and micro biologically. The results revealed improvements in clinical symptoms such as reduction in the depth of the pocket, bleeding on pocket probing and the like for each treatment group in 6-12 weeks. The second and third groups also showed remarked gingival recession. Further more, the density of intrapocket microorganisms showed a remarked decrease up to the 8th week for each treatment group and the population of spirochetes showed a decrease up to the 6th week for the first treatment group and up to the 8th-12th week for the second and third treatment group. The results show that both local application of the TC film and root planing are effective in periodontal treatment, but not the combined treatment.

Collagen↗
PubMed1989

[Application of local drug delivery system to periodontal therapy. 5. Clinical and microbiological effects of TC film application in furcation involvements].

Two molars having furcation grade II involvements were selected from each of six patients with periodontal diseases. One molar received a local application of tetracycline immobilized cross-liked collagen film four times at one-week intervals (TC film-treated group) and the other received no treatment (non-treated group). The clinical and microbiological effects were, as follows, 1. Throughout the experimental period, no significant differences in pocket depth, attachment level, bleeding on pocket probing, periotron unit, gingival index and plaque index were noted between the TC film-treated group and the non-treated group. 2. One week after TC-film application, the treated group showed significant decreases in the density of microorganisms and the proportion of spirochetes compared with the non-treated group. The results revealed the insufficient effectiveness of the local application of TC film by itself for the treatment of teeth having furcation grade II involvements.

Collagen↗
PubMed1989

[Serological classification of Bacteroides gingivalis and purification of group specific antigens].

Bacteroides gingivalis were serologically investigated by the immunodiffusion technique using autoclave-extracted antigens and antisera against whole cells. Fifteen strains of B. gingivalis used in this study, were classified in two distinct serological groups. Eleven strains include strain 381, ATCC 33277 were classified Group A and four strains include strain Su63 were classified in Group B. The group specific antigens from B. gingivalis strain 381 (Group A) and Su63 (Group B) were partially purified from autoclave extracts by 75% ethanol precipitation and anion exchange chromatography, and were identified as polysaccharides composed of glucose (82.3%, 23.7%), rhamnose (7.1%, 12.7%), galactose (4.9%, 18.2%), mannose (2.3%, 1.7%), glucosamine (0.4%, 28.0%) and galactosamine (3.0%, 15.3%).

Antigens, Bacterial↗
PubMed1988

Immunobiological activities of a porin fraction isolated from Fusobacterium nucleatum ATCC 10953.

From Fusobacterium nucleatum ATCC 10953 cell envelope fraction whose inner membranes had been removed by treatment with sodium N-lauroyl sarcosinate, an outer membrane protein (37,000 Mr in a native state) was prepared by extraction with lithium dodecyl sulfate. The protein thus obtained showed distinct porin activity, namely, the ability to form hydrophilic diffusion pores by incorporation into the artificial liposome membrane. The porin fraction exhibited strong immunobiological activities in the in vitro assays: B-cell mitogenicity and polyclonal B-cell activation on murine splenocytes, stimulatory effects on guinea pig peritoneal macrophages, and enhancement of the migration of human blood monocytes. The porin fraction also exhibited immunoadjuvant activity to increase the antibody production against sheep erythrocytes in the spleen of mice that were immunized by sheep erythrocytes with porin. Although chemical analyses revealed that the test porin fraction contained a considerable amount of lipopolysaccharide (LPS) (around 12% of the fraction), the studies with LPS-nonresponding C3H/HeJ mice and on the inhibitory effects of polymyxin B strongly suggest that most of the above bioactivities are due to porin protein itself, not to coexistent LPS in the porin fraction.

Adjuvants, Immunologic↗
PubMed1987

Purification and characterization of extracellular glucosyltransferase from Streptococcus mutans serotype b (subspecies rattus).

An extracellular glucosyltransferase (GT-S) synthesizing water-soluble glucan was purified from the culture supernatant of Streptococcus mutans BHT (serotype b, subsp. rattus) by DEAE-Sepharose chromatography and preparative isoelectric focusing. The Mr of the enzyme was 155,000 and the pI was 4.5. The GT-S had a specific activity of 10.2 i.u. (mg protein)-1, an optimum pH of 6.0 and a Km value of 0.8 mM for sucrose, and was activated twofold by dextran T10. The GT-S was immunologically partially identical with the corresponding enzymes in crude preparations from serotypes c, e and f. The glucan synthesized de novo from sucrose by the GT-S was water-soluble and consisted of 29 mol% of non-reducing terminal, 49 mol% of 1,6-alpha-linked, 11 mol% of 1,3-alpha-linked and 11 mol% of 1,3,6-alpha-branched glucose residues.

Animals↗
PubMed1986

Enhanced instability of IncFII basic replicon by the polA mutation.

IncFII plasmids consisting of a basic replicon and of an additional fragment(s) unrelated to plasmid maintenance were all less stable in polA1 than in its wild type. Reversion to UV-resistance recovered stability and vice versa. UV irradiation promoted instability in polA1 cells. Larger plasmids showed a greater instability and a fewer number of copies in a same host. Surprisingly, polA1 cells with Tn3 on the plasmid showed a higher ampicillin resistance than the wild type, apparently suggesting that the polA1 mutation increases the copy number. The size-dependency of instability was less marked in polA1 than in its parent. Comparison of the generation times has suggested a detrimental effect exerted by a basic replicon in polA1 hosts.

Ampicillin↗
PubMed1986

[Computerized single probe system using a cadmium telluride detector].

Using cadmium telluride (CdTe) as a detector, we assembled a computerized single probe system. The size of the CdTe used is 16 mm in diameter and 2 mm in thickness. Two types of the straight bore collimators of 16 mm in diameter were prepared. One is 16 mm in length (long type) and the other is 5 mm in length (short type). The response curves of the long and short type collimators to 57Co in water showed that the points at 10% of maximum counts were 4 cm and 3 cm in depth along the center axis. The data were accumulated by using a commercialized single cardiac probe system (OMNISCOPE) and processed by itself or transferred to the microcomputer (LSI-11/23) for further analysis. Twenty percent count loss occurred at 100 000 cps with an integral discriminator setting. This system was applied for cerebrospinal fluid (CSF) shunt flow evaluation and measurement of left ventricular ejection fraction (LVEF). Measurement of CSF shunt flow has been able to do in any patient's positioning. In 21 patients with various heart diseases, LVEFs obtained by CdTe detector were compared with those obtained by scintillation detector. There was good correlation between the LVEFs obtained by these two detectors: correlation coefficient (r)=0.939.

Cadmium↗