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E Hoshino

Publications and source records attributed to E Hoshino.

At least 19 recordsLinked to original sources
PubMed2003

Amended biochemical characteristics and phylogenetic position of Treponema medium.

Umemoto et al. (1997, Int J Syst Bacteriol 47, pp. 67-72) proposed spirochete strain G7201, isolated from the periodontal pocket of an adult patient, as a new species, Treponema medium. They deposited this strain in the American Type Culture Collection (ATCC) as type strain ATCC 700293T. Recently, ATCC suggested that there is a discrepancy between the previous report and the results obtained by ATCC in biochemical tests on T. medium ATCC 700293T. In this study, we re-examined and verified the biochemical characteristics of T. medium. The fermentation pattern of carbohydrates of T. medium resembled that of Treponema vincentii and Treponema denticola, but T. medium was clearly differentiated from T. vincentii in the production of indole, and from T. denticola in the hydrolysis of esculin. Also, sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) protein profile analysis and phylogenetic comparison of 16S rDNA sequences revealed that T. medium is clearly differentiated from any established treponemal species, which supports the validity of the proposal of Treponema medium as a new species.

Bacterial Proteins↗
PubMed2002

Penetration of propylene glycol into dentine.

AIM: This study aimed to evaluate penetration of propylene glycol into root dentine. METHODOLOGY: Safranin O in propylene glycol and in distilled water were introduced into root canals with and without artificial smear layer. Dye diffusion through dentinal tubules was determined spectrophotometrically. The time required for dye to exit through the apical foramen using propylene glycol and distilled water as vehicles was also determined. The extent and areas of dye penetration on the split surfaces of roots were assessed using Adobe Photoshop and NIH Image Software. RESULTS: Propylene glycol allowed dye to exit faster through the apical foramen. The area and depth of dye penetration with propylene glycol was significantly greater than with distilled water (P < 0.0001). Smear layer significantly delayed the penetration of dye. CONCLUSION: Propylene glycol delivered dye through the root canal system rapidly and more effectively indicating its potential use in delivering intracanal medicaments.

Coloring Agents↗
PubMed2001

Artificial Pseudomonas aeruginosa biofilms and confocal laser scanning microscopic analysis.

Bacterial biofilms may be formed at various sites, including mucous membranes, teeth, and infectious lesions. To elucidate the structure and the function of biofilms, artificial biofilms of mucoid-type Pseudomonas aeruginosa organisms (strain PT1252) were made by centrifuging the organisms onto the surface of a coverglass and culturing further in broth media supplied continuously (45 ml/h). The biofilm structure at 4, 8, 12, and 24 h was visualized with fluorescent staining (SYTO9, propidium iodide [PI], and/or fluorescein isothiocyanate-concanavalin A [FITC-ConA]) by confocal laser scanning microscopy (CLSM). It was clearly demonstrated that the number of bacteria (10(4)--10(6)/ml) could be estimated by their fluorescence intensity. Sectional analysis of each biofilm layer (1-microm thickness) made it possible to demonstrate the three-dimensional development of biofilms, and revealed that the biofilms were 9 microm in height after 12 h. The live and dead organisms were differentiated by SYTO9 and PI, respectively, in situ in biofilms, and about 13% of the organisms were dead in 12-h-old biofilms. When 12-h-old biofilms were exposed to ciprofloxacin at minimum bactericidal concentration (6.26 microg/ml) for 90 min, all the organisms were killed, but some organisms (11 +/- 1.3%; n = 3) in 24-h-old biofilms with thicker and denser structure were still alive after exposure for 120 min. These results indicate that the CLSM analysis of artificial biofilms was useful for elucidating bacterial functions in biofilms, and may lead to a new quantitative system for estimating the bactericidal efficacy of antibacterial drugs in biofilms.

Anti-Infective Agents↗
PubMed2001

Influence of starvation and biofilm formation on acid resistance of Streptococcus mutans.

The aim of this study was to investigate acid resistance induced by starvation or biofilm formation in Streptococcus mutans ATCC 25175. The artificial biofilms were made on cover glasses, starved for 24 h and immersed in 0.1 M lactate buffer at pH 3.8 for 10 min. The biofilms were also exposed to 5% sucrose solution for 20 min to simulate acid shock produced by sucrose metabolism. Confocal laser scanning microscopy with fluorescein isothiocyanate staining measured the resultant minimum pH in biofilms. Live and dead organisms in biofilms were differentiated by confocal laser scanning microscopy with proidium iodide and SYTO9 staining. The same processes were used to treat planktonic organisms. The results showed that starved biofilms or planktonic cells showed significantly more viable bacteria after acid shock induced either by lactic acid or during sucrose consumption than non-starved biofilms or planktonic cells. In addition, biofilms showed greater resistance to acid shock induced by lactic acid than planktonic cells, whereas similar results were obtained where sucrose was used as a carbon source to reduce pH in biofilms and planktonic cells. Thus, it is suggested that starvation protects both biofilm and planktonic S. mutans from acid shock induced either by lactic acid or during sucrose consumption, while biofilm formation seemed to protect bacteria only from acid shock induced by pH 3.8 lactate buffer but not the acid shock of a slightly higher pH produced during sucrose consumption.

Biofilms↗
PubMed2001

Extracellular polysaccharides do not inhibit the reaction between Streptococcus mutans and its specific immunoglobulin G (IgG) or penetration of the IgG through S. mutans biofilm.

The present study investigated whether extracellular polysaccharides inhibit reaction between Streptococcus mutans and its specific immunoglobulin G (IgG) and penetration of the IgG through S. mutans biofilm. The planktonic organisms with or without extracellular polysaccharides were prepared, incubated with rabbit IgG against whole cell of S. mutans and fluorescein isothiocyanate (FITC)-conjugated goat affinity purified antibody to rabbit IgG. Biofilms with or without extracellular polysaccharides were formed on cover glasses and incubated with rabbit IgG against S. mutans and FITC-conjugated goat antibody to rabbit IgG. Then, biofilms were stained with propidium iodide. The amount of specific IgG binding on S. mutans was determined by FITC intensity with a fluorescence microplate reader. The penetration of IgG through biofilms was determined by confocal laser scanning microscopy. The results showed that the fluorescence intensity of FITC in planktonic organisms with extracellular polysaccharides was similar to that in planktonic organisms without extracellular polysaccharides, indicating that extracellular polysaccharides did not inhibit the reaction between S. mutans and its specific IgG. Although biofilms of S. mutans with extracellular polysaccharides were much thicker and denser than those without extracellular polysaccharides, the speed with which IgG penetrated through both of the biofilms did not differ significantly, suggesting that penetration of IgG through S. mutans biofilm was not affected by extracellular polysaccharides.

Animals↗
PubMed2001

Detection of Slackia exigua, Mogibacterium timidum and Eubacterium saphenum from pulpal and periradicular samples using the Polymerase Chain Reaction (PCR) method.

AIM: The purpose of this study was to detect Slackia exigua from root canal samples using a sensitive PCR amplification method. Mogibacterium timidum and Eubacterium saphenum were also included because of their culture-difficult properties. METHODOLOGY: The species-specific PCR primers were prepared according to 16S rDNA sequence analysis data, and confirmed to be effective for PCR amplification as species-specific, respectively. A total of 36 clinical samples were obtained during the first visit of root canal treatment. RESULTS: The sensitivity of detection was a minimum of 10 organisms for S. exigua and five organisms for M. timidum and E. saphenum, respectively. In seven cases of pulpitis, Sexigua was detected in two cases (29%), and M. timidum in two cases (29%), but E. saphenum was not detected. In 17 cases of root canal treatment, S. exigua was detected in seven cases (41%), M. timidum in 12 cases (71%) and E. saphenum in four cases (24%). In 12 cases of root canal retreatment, S. exigua was detected in three cases (25%), M. timidum in three cases (25%) and E. saphenum in two cases (17%). CONCLUSIONS: S. exigua, M. timidum and E. saphenum were present in root canal systems, and may be associated with pulpal and periradicular pathosis.

Actinomycetales Infections↗
PubMed2001

Intraperitoneal immune cell responses to Eubacterium saphenum in mice.

Oral asaccharolytic Eubacterium saphenum, which are newly isolated gram-positive rods and one of the predominant microorganisms in human periodontal pockets, were injected intraperitoneally in mice to elucidate their pathogenicity in periodontal diseases. Infiltrating immune cells in the peritoneal exudate were quantitated and intracellular T cell (CD4+/CD8+/gammadelta+) production of cytokines IL-4 and IFN-gamma which are related to cellular and humoral immunity, respectively, was determined. Neutrophils appeared first in peritoneal exudates, followed by macrophages and lymphocytes, after the injection of either E. saphenum or Porphyromonas gingivalis. Intracellular IL-4+ and IFN-gamma+ gammadelta T cells were detected in the exudates after the injection of E. saphenum (4.6 +/- 0.8% and 10.1 +/- 1.4%, respectively) and P. gingivalis (5.3 +/- 1.6% and 10.1 +/- 2.1%, respectively). The intracellular production of IL-4/IFN-gamma in CD4+/CD8+ T cells was rather low indicating that the main response was from gammadelta T cells which initiated the immune reactions in mouse peritoneal cavities after injection of E. saphenum or P. gingivalis. Serum IgG and IgM levels were elevated in animals injected with E. saphenum and similarly with P. gingivalis. The present study showed that with slight differences, similar modes of cell response and cytokine and Ig production were observed after intraperitoneal injection of both E. saphenum and P. gingivalis, indicating that E. saphenum may play just as important a role in periodontal diseases as P. gingivalis.

Animals↗
PubMed2001

[Suppressive effect of lansoprazole on anti-Candida activity of murine macrophages].

This study investigated the influences of lansoprazole (AG1749), a proton pump inhibitor (PPI), and its active derivative (AG2000) on Candida albicans growth and the anti-Candida activity of macrophages. Under concentration of 100 microM, AG1749 and AG2000 had no effect on Candida growth. Murine peritoneal macrophages inhibited the growth of C. albicans in vitro. AG2000 suppressed the anti-Candida activity of macrophages dose-dependently, but AG1749 didn't. The suppressing activity of AG2000 for macrophages was neutralized by adding a SH-compound (L-cysteine) in the medium. This suggests that AG2000 may suppress macrophage function in a similar manner with inhibition of proton pump through binding to SH-molecules. When macrophages were preincubated with AG2000 for 1 hr and washed, their anti-Candida activity remained to be partially inhibited for 14 hrs. These results were discussed in relation to the pathogenesis of esophageal candidiasis.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2000

Neutrophil chemoattractant 2 beta regulates expression of the Reg gene in injured gastric mucosa in rats.

BACKGROUND & AIMS: Regenerating (Reg) protein has a trophic effect on gastric mucosal cells. We have shown that Reg gene expression is increased in enterochromaffin-like (ECL) cells during the healing of damaged gastric mucosa around mucosal erosion. This study was designed to explore the stimulants of Reg expression during the healing of gastric mucosal damage. METHODS: Time course changes of the expression of genes for various proinflammatory cytokines and Reg were investigated after induction of gastric mucosal lesions in rats. The direct effect of proinflammatory cytokines on Reg gene expression and Reg protein production were investigated in vitro using counterflow elutriation-enriched rat ECL cells. CXC receptor 2 (CXCR-2) expression was investigated in ECL cells by reverse-transcription polymerase chain reaction. Reg gene expression was also investigated in rats treated by the neutralizing antibody of cytokine-induced neutrophil chemoattractant (CINC-2 beta). RESULTS: During healing, the gene expression of several proinflammatory cytokines and Reg was markedly augmented. Among the proinflammatory cytokines, CINC-2 beta is the only cytokine in which augmented expression preceded the increase of Reg gene expression. In rats treated with CINC-2 beta neutralizing antibody, the augmentation of Reg gene expression was significantly inhibited. When ECL cells were incubated with these proinflammatory cytokines, CINC-2 beta dose-dependently increased Reg messenger RNA and Reg protein in ECL cells. CXCR-2 was identified in isolated ECL cells. CONCLUSIONS: CINC-2 beta, expressed in damaged gastric mucosa, stimulates the production of Reg protein in ECL cells via CXCR-2 and may be involved in the accelerated healing of injured gastric mucosa.

Animals↗
PubMed2000

Description of Mogibacterium pumilum gen. nov., sp. nov. and Mogibacterium vescum gen. nov., sp. nov., and reclassification of Eubacterium timidum (Holdeman et al. 1980) as Mogibacterium timidum gen. nov., comb. nov.

A new genus, Mogibacterium, is proposed for anaerobic, non-spore-forming, Gram-positive, rod-shaped bacteria which have been isolated from the periodontal pockets of adult human patients with periodontal disease and infected root canals. The novel isolates, strains D2-18T, BA11a-f and D5-2T, were inert in most of the conventional biochemical tests and phenotypically resemble asaccharolytic Eubacterium species. The protein profiles of whole cells on SDS-PAGE gels and Western immunoblotting reaction analysis distinguished these organisms from type strains belonging to the previously described Eubacterium species. The G + C content of the DNA is 45-46 mol% for Mogibacterium pumilum and 46 mol% for Mogibacterium vescum. The levels of DNA-DNA relatedness of these new species to other Eubacterium species, including Eubacterium limosum, Eubacterium brachy, Eubacterium lentum, Eubacterium nodatum, Eubacterium saphenum, and the more recently proposed Eubacterium minutum and Eubacterium exiguum (reclassified as Slackia exigua), are less than 2%. The DNA-DNA hybridization value between M. pumilum and M. vescum was 30%. Eubacterium timidum exhibited DNA homologies with Mogibacterium species which were low (17 and 18%) but clearly higher than with all the other Eubacterium species. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the closest phylogenetic neighbour of Mogibacterium species was E. timidum, and that these three species represent a novel lineage distinct from the previously described genera of Gram-positive, rod-shaped bacteria. On the basis of phenotypic characteristics and 16S rRNA gene sequence comparisons, it is also proposed that E. timidum is transferred to the genus Mogibacterium gen. nov. as Mogibacterium timidum gen. nov., comb. nov. (type strain ATCC 33093T).

Adult↗
PubMed1999

Acidic glycosaminoglycans of abdominal mucin in a case of pseudomyxoma peritonei caused by appendiceal cancer.

Although the use of intraperitoneal mucolytic agents is useful in the management of pseudomyxoma peritonei, effective removal of mucin is difficult even by repeated mucolysis in cases with massive ascites. To establish mucolytic therapy as a further effective procedure, biochemical analysis of mucin is required in greater detail. We reported here a case of pseudomyxoma peritonei caused by primary appendiceal cancer with biochemical analysis of mucin. The abdominal cavity in this case was filled with massive mucinous ascites. Although the mucolytic therapy was performed repeatedly, it was not effective in preventing mechanical ileus which was followed by surgical exclusion. Biochemical study of mucin showed that the mucin contained a small amount of hyaluronic acid, as characterized by electrophoretic study. These data led us to the hypothesis that the hyaluronic acid component plays a role in the pathogenesis of the replacement of mucin in the abdominal cavity.

Aged↗
PubMed1999

Cryptobacterium curtum gen. nov., sp. nov., a new genus of gram-positive anaerobic rod isolated from human oral cavities.

Novel Eubacterium-like isolates, strains 12-3T and KV43-B, which were isolated from the periodontal pocket of an adult patient with periodontal disease and necrotic dental pulp, respectively, were studied taxonomically and phylogenetically. The morphological and differential biochemical characteristics of these organisms are also described in this paper. These organisms were Gram-positive, anaerobic, non-spore-forming, rod-shaped bacteria that were inert in most of the conventional biochemical tests and closely resembled members of asaccharolytic oral Eubacterium species. On the other hand, protein profiles of whole cells in SDS-PAGE and Western immunoblotting reaction analysis distinguished these isolates from strains of the previously described genus Eubacterium. The G+C content of the DNAs from the novel isolates was 50 and 51 mol%, respectively. The levels of DNA-DNA relatedness to other asaccharolytic oral Eubacterium species, including Eubacterium brachy, Eubacterium lentum, Eubacterium nodatum, Eubacterium timidum, Eubacterium saphenum, Eubacterium minutum and Eubacterium exiguum, was less than 11%. These organisms also exhibited a very low level of reassociation with the DNA of Eubacterium limosum, the type species of the genus Eubacterium. The results of 16S rDNA sequence comparisons revealed that these organisms represent a novel lineage distinct from all previously described genera of Gram-positive, rod-shaped bacteria. On the basis of our results, it is suggested that strains 12-3T and KV43-B should be classified in a new genus and species, for which the name Cryptobacterium curtum gen. nov., sp. nov. is proposed. The type strain of Cryptobacterium curtum is 12-3T (= ATCC 700683T).

Adult↗
PubMed1999

[Recent advance in evaluation of lung function of obstructive lung disease].

Chaos of the abdominal movement was examined in obstructive lung disease. Body inductive plethysmograph was used and the analog record was digitized at sampling interval of 100 ms. Correlation dimension was calculated according to the method of Grassberger-Procaccia. In chronic obstructive lung disease and chronic pulmonary emphysema (CPE), correlation dimension was positively correlated with respiratory frequency. The degrees of freedom were between 3-6. The subjects with CPE with periodic breathing showed a lower correlation dimension, which was comparable with Cheyne-Stokes respiration. One subject with dyspnea due to asthmatic attack showed a higher dimension than at the time of remission. Assessment of respiratory chaos may provide a new way of approach to elucidate breathing impairment in obstructive lung disease.

Abdomen↗
PubMed1998

Bactericidal efficacy of carbon dioxide laser against bacteria-contaminated titanium implant and subsequent cellular adhesion to irradiated area.

BACKGROUND AND OBJECTIVE: The aim of this study was to assess CO2 laser ability to eliminate bacteria from titanium implant surfaces. The changes of the surface structure, the rise in temperature, and the damage of connective tissue cells after laser irradiation were also considered. STUDY DESIGN/MATERIALS AND METHODS: Streptococcus sanguis and Porphyromonas gingivalis on titanium discs were irradiated by an expanded beam of CO2 laser. Surface alteration was observed by a light, and a scanning electron, microscope. Temperature was measured with a thermograph. Damage of fibroblastic (L-929) and osteoblastic (MC3T3-E1) cells outside the irradiation spot and adhesion of the cells to the irradiated area were also estimated. RESULTS: All the organisms (10(8)) of S. sanguis and P. gingivalis were killed by the irradiation at 286 J/cm2 and 245 J/cm2, respectively. Furthermore, laser irradiation did not cause surface alteration, rise of temperature, serious damage of connective tissue cells located outside the irradiation spot, or inhibition of cell adhesion to the irradiated area. CONCLUSION: CO2 laser irradiation with expanded beam may be useful in removing bacterial contaminants from implant surface.

Animals↗
PubMed1998

Differentiation of oral Actinomyces species by 16S ribosomal DNA polymerase chain reaction-restriction fragment length polymorphism.

16S rDNA polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to generate restriction profiles of the reference strains, including the American Type Culture Collection type strains, of oral Actinomyces spp., i.e., A. israelii, A. gerencseriae, A. naeslundii genospecies 1 and 2, A. odontolyticus, A. meyeri and A. georgiae, and 23 Actinomyces strains isolated from human dental plaque. The 16S rRNA gene sequences from isolated genomic DNA samples were amplified by PCR. The PCR products were purified and characterized by single digestion with four restriction endonucleases, i.e., MnlI, HaeIII, CfoI, or HpaII. Among them, MnlI was found to discriminate the respective reference strains. The clinical isolates were assigned to one of the species, i.e., A. gerencseriae, A. naeslundii genospecies 1 and 2 and A. odontolyticus, on the basis of their restriction profiles by single digestion with MnlI. Thus, 16S rDNA PCR-RFLP, using MnlI, is a rapid and reliable method for the differentiation of oral Actinomyces spp.

Actinomyces↗
PubMed1998

Experimental chronic infection induced in mice by Actinomyces israelii entrapped in alginate gel.

Tissue responses to experimentally induced actinomycotic lesions were investigated in mice by both light and transmission electron microscopy. Micro-organisms of Actinomyces israelii were entrapped in alginate gel and injected into the subcutaneous tissue over the periosteum of the mouse cranium. One day after the injection (initial stage), a non-stained amorphous structure was located in the core of the lesion, corresponding to the injected gel with bacteria. Numerous neutrophils surrounded the core region and phagocytized the injected complex actively. At days 3-7 (intermediate stage), the lesion became well developed. The core structure became eosinophilic and separated to form island-like structures. No lesion was recognized in the control group (gel without bacteria) until day 14. After 30 days (late stage), the lesions displayed more static features, similar to the "sulphur granules" characteristic of actinomycotic lesions. At the late stage, foamy cells increased in number and took the place of neutrophils in the alginate islands. By transmission electron microscopy these foamy cells were seen to be filled with lysosomal vesicles containing electron-dense foreign material. Thus, these cells appeared to be macrophages that had phagocytized degenerated neutrophils containing bacteria. Along with the active phagocytosis by foamy cells that progressed in the late stage, a collagenous capsule became conspicuous and separated the lesion from the intact tissue. The bacteria remained in the gel islands until at least day 60, although they considerably decreased in number with time. Serum IgG antibody titres began to rise within 24 h of the injection, reached a peak concentration at day 14 and remained a significantly high (p < 0.01, vs 0 time) until day 120. These results suggest that this animal model is useful for inducing experimental chronic infectious lesions.

Actinomyces↗
PubMed1998

Bacterial eradication from root dentine by ultrasonic irrigation with sodium hypochlorite.

The study aimed to evaluate intracanal irrigation procedures in eradicating bacteria from surface, shallow and deep layers of root dentine using extracted human teeth. Artificial bacterial smear layer was successfully produced by rubbing a mixture of dental plaque and artificially decalcified dentine or carious dentine on root canal walls. The reservoir holes were 3.5 mm in depth, 1 mm in diameter prepared 1.5 mm apart and parallel to the root canals on the decrowned planes, in which five separate bacterial species were placed (Actinomyces israelii, Fusobacterium nucleatum, Propionibacterium acnes, Streptococcus mutans and Streptococcus sanguis). Bacterial eradication after irrigation of the prepared canals was determined by bacterial recovery (i) from the root canal surfaces and shallow layers where bacteria were smeared artificially and (ii) from deeper layers of root canal dentine reservoir holes. Ultrasonic irrigation with 5.5% and 12% NaOCl eradicated bacteria from artificial smear layer (P < 0.0001), whilst 12% NaOCl irrigation with a syringe was insufficient. Ultrasonic irrigation with water or 15% EDTA-failed to eradicate bacteria from smeared surfaces. Ultrasonic irrigation with 12% NaOCl killed A. israelii, F. nucleatum, P. acnes, S. mutans, and S. sanguis placed in reservoir channels, although for F. nucleatum, a very small number of bacteria remained in five samples out of 12. Ultrasonic irrigation with less concentrated NaOCl failed to eliminate bacteria completely from reservoir channels in most samples. Ultrasonic irrigation with 12% NaOCl appeared to eliminate bacteria efficiently from surface, shallow and deep layers of root dentine.

Actinomyces↗