The mere exposure effect () is the phenomenon that repeated exposure to a stimulus promotes preference for that stimulus. Conventionally, the has been observed as a result of successive presentation of a single object. This study instead examined whether the simultaneous exposure to multiple stimuli could modulate the . The participants observed the stimulus display consisting of 1-25 stimulus elements and evaluated their preference for them. The results showed that the multiple element display produced a significant when the stimulus elements were presented within the central visual field. More importantly, the exposure to the multiple element stimulus produced a stronger when the number of elements was moderate. The present results suggest that the simultaneous exposure to multiple stimulus elements could facilitate the but only when the number of stimulus elements does not exceed the capacity of processing resources.

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Triamcinolone acetonide (TAC), a synthetic glucocorticoid, induces cleft palate resulting from poor development of palatal shelves in mice. However, TAC has no effect on medial edge epithelial cells ( cells) in secondary palatal shelves. In the present study, we examined the relationship between the pathogenesis of cleft palate and the effects on cells and palatal mesenchymal cells in rat embryos/fetuses exposed to TAC. Pregnant Wistar Hannover rats were given TAC intramuscularly at 0.5 mg/kg at gestation days (Day) 12, 13, and 14, then embryos/fetuses were harvested on Days 14.5, 15, 16 and 20. The effects of TAC were as follows; an inhibition of palatal mesenchymal cell proliferation on Day 14.5, a decrease in the density of palatal mesenchymal cells and cells, and expression of epidermal growth factor (EGF) receptors in cells on Day 15, and stratified squamous differentiation of cells with expression of cytokeratin and EGF receptors on Day 16. These findings indicated that TAC inhibited the proliferation of mesenchymal cells and affected the differentiation of cells into stratified squamous epithelia in the palatal shelves of rat embryos. However, these stratified squamous cells partially fused with each other. Thus, we suspected that a major contributing factor to the formation of TAC-induced cleft palate might not be the altered differentiation of cells, but the inhibition of mesenchymal cell proliferation.

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In this paper, we presented a new procedure to determine daily minimum energy expenditure () in free-moving rats and mice kept in a chamber. Energy expenditure was measured for 23h period and averaged every 10min. Data were sorted in ascending order. was estimated from the regression line with the smallest slope and the biggest intercept among the regression lines calculated between the sorted energy expenditure and the data ranking. Among three duplicate measurements in individual animals, gave the smallest coefficient of variation (2.2%) as compared with actual measured-values: either the single lowest value (4.0%) or the average of the 6 lowest values (2.5%). Judging from diurnal patterns of energy expenditure and locomotor activity and from video tape observation of the rat's performance, it was confirmed that represented an energy expenditure at rest. decreased with fasting from days 1 to 5. per body weight also declined with age, but stayed around 71-72kcal/day/kg^3/4 at 18 and 34 weeks of age in male Wistar rats. in mice increased at lower ambient temperatures between 16 and 32°C, but stayed fairly constant at the same temperature in repeated experiments. Thus, estimated by the present regression procedure was highly reproducible and valid to determine the fundamen-tal value of daily energy expenditure under free-moving conditions.

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Bactericidal activities of benzalkonium chloride [also known as alkyldimethylbenzylammonium chloride (ADBAC)] containing nonionic surfactants such as methyl ester ethoxylates () with the alkyl group C8–C14 and oxyethylene (EO) group of average adduct number 3–15 were measured against Escherichia coli and Staphylococcus aureus. Sample solutions containing in the vicinity of the critical micelle concentration exhibited a dramatic decrease in viable bacterial counts. with an alkyl group of C12 and an oxyethylene group of lower adduct number exhibited little viable bacterial counts than those having higher EO adduct numbers. with reduced EO adduct numbers increased fluorescence intensity in E. coli using the viability stain SYTO 9. Our results show that molecules with low EO adduct numbers exhibited bactericidal activity by increasing the permeability of the E. coli cell membrane. Sample solution containing ADBAC and molecules with lower EO adduct numbers also displayed higher zeta potentials. Moreover, ADBAC molecules incorporated into micelles of with lower EO adduct numbers were adsorbed onto the surface of E. coli, which augmented bactericidal activity.

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The present study aimed to investigate the pathways and fates of medial edge epithelial () cells in organ culture of the mouse palatal shelve in combination with vital-dye labelings and in situ confocal observation of labeled cells. Embryos at E13.5-13.7 were used to collect palatal shelves for organ culture. Epithelia of the palatal shelves were labeled with two fluorochromes, CCFSE and DiI. The organ culture was validated histomorphologically to assimilate in vivo palatogenesis at least with respect to sequential events at the midline, i.e., the formation and discontinuity of the epithelial seam and the mesenchymal confluence. Immunohistochemistry showed that extensive cell death was evoked at the midline seam and triangles over the entire fusion processes. Alexa-tagged ssDNA immunostaining showed that, by 6 h after the cells were placed in contact, the first sign of cell death was observed within the intact epithelial seam, distributing along the whole length of the midline seam as well as the triangle. A majority of the labeled cells exhibited motility and followed pathways toward the oral and nasal ends, where the triangular morphology was generated. A relatively small number of cells crossed over the basal lamina and executed phenotypic changes in the mesenchyme. The combined localization of the fluorescence and cytokeratin markers confirmed a loss of epithelial phenotype in fractions of the cells after their migration into the mesenchyme. Their histological appearance indicated that they remained viable after leaving the epithelial population. These results support the theory that multiple cellular events, namely apoptosis, migration, and epithelial-mesenchymal transformation (EMT), most likely contribute to palatal shelf fusion and that apoptosis may be a major contributor for the removal of cells and activation of adjacent cells.

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Recent in vivo and in vitro studies have suggested that medial edge epithelial () cells covering the lateral palatine shelves do not undergo cell death, but migrate into the oral and nasal epithelium or transform into mesenchymal cells. We, therefore, reexamined the fate of cells during palatal fusion in rat embryos by in situ 3′ nick end labeling of dUTP (TUNEL), electron microscopy, and immunohisto/cytochemistry. TUNEL staining revealed positive nuclei in the medial edge epithelium immediately prior to contact, in epithelial triangles formed between the epithelial seam and nasal or oral epithelium, in epithelial pearls, and in mesenchymal tissue near the epithelium. However, these TUNEL-positive cells were rarely present in the epithelial seam. Electron microscopy revealed cells showing nuclear chromatin condensation and cell shrinkage, and apoptotic bodies in the fusing epithelium; these often contained apoptotic body-like structures as heterophagosomes. By double staining using a laser scanning microscope, TUNEL-positive nuclei were co-localized with lysosomal cysteine proteinases, cathepsin B or L in and mesenchymal cells adjacent to the epithelium. These results suggest that cells undergo apoptosis during the palatal formation, even though they migrate into epithelial triangles or transform into mesenchymal cells. Moreover, apoptotic bodies and cellular debris were phagocytosed by adjacent cells or mesenchymal cells and digested by lysosomal enzymes.

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Multielectron excitations () have been investigated using X-ray magneticcircular dichroism at the K-edge in 3d transition metal ferromagneticand ferrimagnetic compounds.The dichroic signal is located in the energy range 50 to 70, eV abovethe absorption edge.The intensity is of the order of 10^-3 of the photoabsorption, comparable to the dichroism observed around the edge.The energy position is dependent on the absorbing magnetic atoms ratherthan the material structures.The energy difference between the K-edge and the peak varies linearlywith the atomic number Z, and is related to the absorption energy of theM_{2, 3}-edge of the (Z+1) atom.These features suggest that the 3d-states have a significant contributionto the process.We propose that this phenomenon is due to the super Coster-Kronigtransitions described as the final state (1s)¹(3p)⁵(3d)ⁿ⁺², in which two electrons are simultaneously excited to the 3d-orbitals.

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In order to prepare a composite material having dimensional stability and hygroscopicity similar to wood itself, the liquid phase reaction of ethylene glycol (EG) and 4, 4'-diphenylmethane diisocyanate (MDI) with heartwood of Hinoki (Chamaecyparis obtusa SIEB. et ZUCC.) was investigated. The hygroscopicity and dimensional stability were evaluated by the amounts of hydroxyl group and combined urethane which were introduced into wood.
In the reaction of EG and MDI in wood, the nitrogen content and the reactant combined with wood components increased with an increase in mole fraction of MDI in MDI-EG system, but the degree of crystallinity decreased. This shows that the reaction took place somewhat in the crystalline region. The formation of urethane in the treated wood was also identified.
The anti-swelling efficiency (ASE) and moisture-excluding efficiency () showed the maximum values at about 0.5 of MDI mole fraction in any concentration of solutions. ASE and were 69.3% and 59.4% at 15% concentration, respectively. ASE was directly proportional to the and bulking. When the free EG was removed from the treated wood, ASE and decreased remarkably, and tended to decrease with an increase in ASE. It suggests that free EG considerably affects ASE, and bulking.

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We have reported the biochemical analysis of acidic glycosaminoglycans (AGAG) in middle ear effusions (), by use of two-dimentional electrophoresis using cellulose acetatic strips in order to know the nature of . In the present study, radioautography on Dowex 1 × 2 column chromatography was carried out to analyze the composition of AGAG.
Results of the present study found, 1) that contain dermatan sulfate besides hyalulonic acid, low sulfated chondroitin sulfate and heparan sulfate. And 2) that total AGAG content is not difference between mucoid and serous . By the radioautography, an unidentified slow component was found, which may concern the viscoelasticity of .

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To clarify the biochemical properties, particularly causative components of the viscoelasticity of middle ear effusions (), glycosaminoglycans (AGAG) were analyzed in 41 mucoid and 21 serous aspirated from 44 patients, aged between 2 and 15, with otitis media with effusion; and in nasal secretions (NS) and sera from corresponding patients. The concentration of total AGAG was calculated by the amount of uronic acid. Two-dimentional electrophoresis using cellulose acetate strips was carried out to analyze the composition of AGAG.
Results of the present study found, 1) that total AGAG content is significantly greater in mucoid than in serous , 2) that contain hyaluronic acid, lowsulfated chondroitin sulfate, heparan sulfate, and sialoglycoprotein. These components were also found in many samples of NS, but components of AGAG in sera differed from those of and NS.
At present, we could not settle what components of mucopolysaccharides mostly concern the viscoelasticity of . Further investigative effort should be done.

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To investigate the nature of middle ear effusion (), secretory IgA, serum type IgA, and albumin were measured respectively by electrommunodiffusion method in 87 mucoid effusions and 54 serous effusions. Antibody activities of secretory IgA against the M antigen of streptococcus pyogenes were also investigated by ELISA in order to clarify the mucosal immume activity of middle ears affected by otitis media with effusion (). The mean value of secretory IgA was 2712.6±1267.4μg/ml in mucoid , and 854.6±1060.8μg/ml in serous : while the mean value of serum type IgA was 2919±2308.9μg/ml in the mucoid group, and 4862.4±3387.4μg/ml in the serous group. These differences were statistically significant. The mean level of albumin concentrations in was twice of that in sera. An appreciable antibody of secretory IgA to the M protein, which was between 11 to 68 ng/ml, was found in 17 of 77 (22%) mucoid , and in 5 of 41 (12%) serous . Findings of this study suggest that is a muxture of secretions and transdate, that the accumulation of fluid, and water absorption, may occur in the tympanic cavity, and that middle ears affected by OME provide mucosal immunity preventing bacterial infection.

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The purpose of this work is to evaluate etiologic factors in otitis media. By using Boyden Chamber method, we investigated the functions of neutrophils in middle ear effusions () to clarify their role in the chronicity and progression of middle ear inflammation.
In addition, chemotactic activity of was also investigated by measuring the chemotaxis of normal neutrophils incubated with .
The results were as follows;
Chemotactic index (C. I) of middle ear neutrophils (MEN) was higher in 40% of cases with otitis media than that of peripheral blood neutrophils.
C. I in the group in which neutrophils were incubated with was higher than that in the group studied without .

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KATAYAMA, M. and KAN, M. Heparin-Binding (Fibroblast) Growth Factors are Potential Autocrine Regulators of Esophageal Epithelial Cell Proliferation. Tohoku J. Exp. Med., 1992, 168 (2), 287-290-A serum-free culture system supplemented with neural tissue extract for normal human esophagus was applied to the culture of mouse esophageal epithelium. Similar to mouse mesenchyme and skin epithelium, esophageal epithelial lines () emerged after serial culture. The cells had an apparent unlimited life-span, but retained morphology and other characteristics of normal epithelial cells. A screen for growth factors that stimulated growth of cells in the absence of neural extract revealed that epidermal growth factor (EGF) and heparin-binding (fibroblast) growth factors (HBGF) were most effective. An HBGF-like activity was apparent in extracts of rapidly proliferating, but not quiescent cells at low or confluent densities. A cloned cell line (/C8) was selected from cell cultures in the absence of neural extract. /C8 cells proliferated independent of either EGF or HBGF at rates equal to cells, cell extracts exhibited HBGF-like activity at all stages of proliferation, and the cells formed invasive tumors in syngenic hosts. The HBGF-like activity present in extracts of tumorigenic /C8 cells had properties similar to HBGF-1 (acidic fibroblast growth factor).-esophagus; epithelial cells; heparin-binding growth factors; FGF; autocrine mechanisms

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The etiology of otitis media with effusion (OME) has not been conclusively established. The biochemical characteristics of middle ear effusion () indicate inflammatory state. Although prostaglandins (PGs) have been detected in , the exact measurement of PGs has not been made. In this study, concentrations of PGs were measured by radioimmunoassay (RIA) in human . Each sample of from OME was devided into two groups, which were serous effusions and mucoid ones. The main PG in both serous and mucoid effusions was TXB₂, followed by PGE₂. PGD₂, PGF_2α, and 6ketoPGF_1α were also found in with a smaller quantity. The amounts of each PGs in mucoid effusions were two or three times higher than those in serous effusions. But protein concentration is almost the same between mucoid and serous group. These results suggest that PGs may play important roles as a mediator of the inflammatory response in the pathogenesis of .

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To elucidate the pathogenesis of otitis media with effusion (OME), the role of cytokines was investigated by analyzing the middle ear effusion () obtained from patients with this disease and from experimental animal models. Enzyme-linked immunosorbent assay (ELISA) of the revealed that levels of IL-1β and IL-8 were higher in the mucoid type than in the serous type and were significantly increased in neutrophil-rich groups. Gene targets of those cytokines were also detected in pellets of the by RT-PCR. However, the incidence of IL-6 and IL-8 detected by RT-PCR was lower than that detected by ELISA, suggesting that those cytokines were produced by the middle ear mucosa as well as inflammatory cells infiltrating the .
In the animal experiment, OME was induced in mice by intra-tympanic inoculation with an endotoxin, and the levels of IL-1β in the were significantly increased. Intra-tympanic inoculation with rIL-1β also produced the and the cytological findings of the as well as the histological findings of the middle ear mucosa were similar to those found in endotoxin-induced OME. Furthermore, an intra-tympanic injection with anti-IL-1 receptor antibodies reduced the incidence of OME induced by an endotoxin or rIL-1β, suggesting that IL-1β may play an important role in the pathogenesis of OME.
This clinical study demonstrated that macrolide was effective for OME and decreased the levels of inflammatory cytokines in the including IL-1β and IL-8. Animal experiments also showed that co-administration of macrolide reduced the incidence of endotoxin-induced OME and the concentration of IL-1β in the .
These findings suggest that cytokines play an important role in the pathogenesis of OME and that a cycle of the cytokine network might be associated with the persistence of this disease.

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The role of allergy, particularly allergic rhinitis (AR), in otitis media with effusion (OME) is discussed. Because both OME and AR are common in young children, these disorders are occasionally seen in the same patient. Many clinical and experimental reports have discounted the allergies as a cause of middle ear effusion () because type I allergic reactions in the nose cause eustachian tube dysfunction but do not induce , because the associated tubal dysfunction has a short duration. It has been shown that allergy-induced tubal dysfunction significantly disturbs the clearance of . Since clinical and experimental studies have demonstrated the efficacy of allergy treatment in patients or animals having both diseases, combination treatment for allergy and OME in patients with both diseases should be initiated.

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This study was undertaken to establish whether or not DSPC (disaturated phosphatidylcholine) was present in the middle ear effusion (). Our results showed that DSPC/PC ratio of was much higher than that of serum. These results suggested that the source of supply of phospholipid in the might be not only blood but also middle ear mucosa.

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