Biomedical subjects

Y Sakakura

Publications and source records attributed to Y Sakakura.

At least 163 records · Page 9Linked to original sources

PubMed1989

Hemophilus influenzae adherence to and absorption from the nasal mucosa of guinea pigs.

The adherence to and the absorption from nasal mucosal epithelium of type b and non-typeable strains of Hemophilus influenzae were studied in guinea pigs. H. influenzae bacteria were administered to the nose as 4 x 10(7) organisms in 1.0 ml saline. The outer membrane vesicles (OMV) of H. influenzae were used in the absorption study. Scanning electron microscopic studies showed that H. influenzae cells attached to both ciliated and non-ciliated cells of the nasal mucosa. Histological studies showed that OMV were absorbed through the nasal mucosa, mainly from ciliated cells. Further, penetration of OMV through the nasal mucosa of immunized animals was reduced when compared with that of non-immunized ones.

Animals↗

PubMed1989

Secondary syphilis of the tonsil.

An 18-year-old man with an ulceration of his right tonsil and cervical lymphadenopathy was examined. The patient also had a papular eruption in his face, chest, abdomen, and upper extremities. There were no signs of genital involvement. Routine serological tests for syphilis were reactive and histological findings of a cervical lymph node biopsy were characteristic for syphilitic lymphadenitis. Spirochetes were also identified in the tissue sections. A diagnosis of secondary syphilis of the tonsil with cervical syphilitic lymphadenitis was made. In recent years, the number of new cases of syphilis has increased in Japan. Since the oral cavity is the most common extragenital site of syphilis, clinicians should bear in mind that oral lesions from an unknown cause might possibly be syphilitic.

Adult↗

PubMed1989

A simple, disposable, and improved organ culture system for maintaining three-dimensional development of mouse embryonic molars.

Mandibular first molars from 17-d-old mouse embryos were cultured in vitro for 2 to 4 d by a simple, disposable, improved floatation method. This method consisted of using a 24-well multidish and a plastic culture chamber with a membrane filter. The improved floatation method, as well as our previous method, was capable of the three-dimensional development of tooth germs. Cytodifferentiation of odontoblasts and ameloblasts and formation of extracellular matrices were accelerated by the present culture system, in comparison with our previous method. All the molars cultivated by this method were very similar in morphology to in vivo. On Day 2 of culture the terminal cytodifferentiation of odontoblasts and the formation of predentin were ascertained in the bucco-lingual sections of the cultured molars. A thick layer of predentin was formed at the tip of the cusp and gradually decreased toward the cervical loop and the fissure between the buccal and lingual cusps. On Day 4 in vitro, secretory ameloblasts produced enamel matrix, and the mineralized enamel showed showed prismatic structure very similar to that in vivo. Dentin and predentin also were normal in ultrastructure. The extracellular matrices (enamel, dentine, and predentin) were formed in line with the pattern of the cusp and the formation of matrices normally started at the tip of the cusp. We conclude that the three-dimensional development of whole tooth germs in vitro may be very important for normal expression of the developmental program intrinsic to mouse embryonic molars.

Animals↗

PubMed1989

Immunohistochemical and cytochemical evidences for a possible localization of leucine aminopeptidase in the Merkel cell granule.

Localization of leucine aminopeptidase (LAP) in the Merkel cell-axon complex was studied immunohistochemically and cytochemically in the labial tissues of the mouse, rat, dog, and monkey. Anti-LAP was obtained in rabbits by the injection of commercially supplied swine LAP which was confirmed as electrophoretically pure. The Merkel cells of the mouse, rat, and monkey were positively stained by treatment with anti-LAP but the Merkel cells of the dog were negative. When ultrathin sections of the hair follicle from the rat whisker pad, which contain an abundance of Merkel cells, were processed by immuno-peroxidase or by the immuno-gold method, the reaction products were predominantly deposited on the Merkel cells granules. Furthermore, an immuno-blot assay revealed that an extract of the hair follicles from murine whisker pads contained a molecule of relative molecular mass Mr = 60,000 which is similar in size to a subunit of swine LAP. Thus, it appears that Merkel cell granules of rodents and the monkey contain a protein which resembles lucine aminopeptidase.

Animals↗

PubMed1989

Anaplastic small cell carcinoma of the larynx.

Anaplastic small cell carcinoma of the larynx is an uncommon neuroendocrine tumor. We report a case of this neoplasm of a 53-year-old male. The patient showed persistent hyponatremia accompanied with continuous loss of sodium in the urine, which resulted from inappropriate secretion of antidiuretic hormone (ADH). It is postulated that hyponatremia in this case was due to production of ADH by the tumor cells.

Carcinoma, Small Cell↗

PubMed1989

Morphological evidence of the formation of intracellular collagen fibrils in the embryonic mouse molar odontoblasts induced by colchicine administration.

The effects of colchicine on collagen formation were examined ultrastructurally using secretory odontoblasts in mouse molar tooth germs isografted to the spleen for 1 week. Colchicine in concentrations of 0.025 or 0.05 mg/0.1 ml was injected intravenously 12-24 h prior to harvesting. Colchicine induced the disruption of the Golgi apparatus and caused the accumulation of various types of Golgi-associated vacuoles containing collagenous fibrillar structures. Many vacuoles containing fine particles, nonstriated parallel filaments, banding patterns with a periodicity of approximately 63-nm intervals, and occasionally segment-long-spacing-like assemblies were aggregated in the cytoplasm during the experimental period. These morphological changes in vacuole contents may reflect the initial steps for polymerization of the intracellular collagen fibrils. The majority of the aggregated vacuoles were degraded by fusion with lysosomes but banded filamentous material in some vacuoles appeared to polymerize into the collagen fibrils with native structures. These results suggested that in unsecreted vacuoles accumulated in the odontoblasts as a result of colchicine administration the polymerization of collagen fibrils with native structures can occur.

Animals↗

PubMed1989

Protease inhibitors in middle ear effusions from experimental otitis media with effusion: kinetics of alpha 1-antitrypsin and alpha 2-macroglobulin levels.

Alpha 1-antitrypsin (alpha 1-AT) and alpha 2-macroglobulin (alpha 2-M) were measured by both immunochemical and functional assays in paired plasma and middle ear effusions (MEEs) from experimental otitis media models (serous otitis media [SOM], purulent otitis media [POM], and SOM + POM). The MEE/plasma ratio of alpha 1-AT in SOM was significantly higher than that in POM (p less than .01) because of the high alpha 1-AT level in POM plasma. The ratio of both antitryptic activity and trypsin-binding activity in POM was significantly higher than that in SOM + POM (p less than .01, less than .05), and significantly lower than that in SOM (p less than .01). The majority of both inhibitors in SOM exists as the free state, and the reaction between proteases and inhibitors in POM and SOM + POM is more active than that in SOM. It is concluded that both alpha 1-AT and alpha 2-M appear to play an important role in the protection of middle ear mucosa by forming protease-inhibitor complexes to reduce proteolytic damage in POM and SOM + POM models.

Animals↗

PubMed1989

Prognosis of secretory otitis media in relation to viscoelasticity of effusions in children.

Both elasticity (G') and viscosity (eta') of middle ear effusions (MEEs) were measured with an oscillating sphere magnetic rheometer and compared with continuance of fluid retention in 93 ears of 69 children with otitis media with effusion (OME). The ears were divided into four groups according to the viscoelastic properties of MEEs at the first myringotomy. Eight-four percent of the ears in group 2 were free from effusion within 4 months; the difference from the other groups was statistically significant. These results indicate that the mucociliary clearance function plays an important role in the process of recovery from OME.

Child↗

PubMed1989

Biochemical study of protease inhibitors in normal chinchilla middle ear.

Protein concentration and inhibitory capacity of both alpha 1-antitrypsin (alpha 1-AT) and alpha 2-macroglobulin (alpha 2-M) were measured in plasma and middle ear bulla (MEB) washings of chinchillas by use of specific antisera against chinchilla alpha 1-AT and alpha 2-M. Low molecular weight (LMW) trypsin inhibitor also was analyzed in MEB washings. Chinchilla alpha 2-M showed a common antigenicity with human alpha 2-M. The mean value of alpha 1-AT in chinchilla plasma was 412.0 +/- 87.8 and that of alpha 2-M was 435.0 +/- 117.1 mg/dL. There was a significant relationship between alpha 1-AT level and antitryptic activity, and between alpha 2-M level and trypsin binding activity in plasma. The majority of alpha 1-AT and alpha 2-M in plasma is present as free inhibitors unsaturated with proteases. The MEB washings had significant antitryptic activity, which is attributed to both alpha 1-AT and LMW trypsin inhibitors. Inhibitory functions of alpha 1-AT and LMW trypsin inhibitors appear to play an important role in the defense of the normal middle ear mucosa.

Animals↗

PubMed1989

Proteases and protease inhibitors in immune complex otitis media in chinchillas.

Using an immune complex-induced (IC) otitis media model in chinchillas sensitized with human serum albumin (HSA), we measured the levels of protease activity, protease inhibitors, and HSA in the middle ear fluid (MEF). The effect of a corticosteroid agent (triamcinolone) on the degree of IC otitis media also was studied. The levels of protease inhibitors alpha 1-antitrypsin and alpha 2-macroglobulin in the MEF were significantly higher than in nonsensitized animals. Fibrinolytic (plasminogen activator [PA]) activity was detected in the MEF; however, only a small level of activity of nonspecific proteases was detected because of the significant level of antitryptic activity in the MEF. The levels of protease inhibitors and PA activity were significantly reduced by the steroid treatment. It is concluded that protease inhibitors play an important role in the protection of the middle ear mucosa and that corticosteroid treatment can reduce the severity of IC otitis media.

Animals↗

PubMed1989

In vitro effects of calcitonin and/or parathyroid hormone on odontogenesis of mouse embryonic molars.

Mandibular first molars of mouse embryos were cultivated for examination of the effects of calcitonin (CT) and/or parathyroid hormone (PTH) on the odontogenesis of the molars, and for determination of whether and how CT, which is a PTH antagonist, has an influence on the effect of PTH on odontogenesis. On the second day, the inner enamel epithelium in the control group had already differentiated into pre-ameloblasts. Typical odontoblasts had secreted a layer of predentin. On the fourth day of culture, the pre-ameloblasts achieved terminal differentiation into secretory ameloblasts, and enamel and dentin had already been deposited. PTH (1 unit/mL) inhibited the odontogenesis of the cultured molars during the designated culture periods (two and four days), while CT (0.5 unit/mL) stimulated odontogenesis. On the second day, the development of the molars in the CT + PTH group showed an intermediate stage between the control and PTH-treated explants, but on day 4 it corresponded to that of the controls. Moreover, when the molars exposed to PTH for two days were untreated and treated with CT for an additional two days, the former produced a small quantity of enamel matrix, while the latter formed a large amount of the matrix. These histological findings were also supported by a morphometric analysis of the enamel matrix in the cultured molars. The present results suggest that CT stimulates, but PTH suppresses, the odontogenesis of the mouse embryonic molars, and that CT is an antagonist to the inhibitory effect of PTH on odontogenesis.

Amelogenesis↗

PubMed1989

[Psychosomatic aspect of a choking lump sensation in the throat].

In order to elucidate the relationship between a choking lump sensation in the throat and psychosomatic status, the authors subjected 339 in-patients above 17 years of age with various kinds of otorhinolaryngologic diseases and evaluated their psychosomatic conditions by means of two questionnaires: Cornell Medical Index Questionnaire (CMI) and Maudsley Personality Inventory (MPI). According to the answer to one of the CMI questions "Do you often feel a choking lump in your throat?", the patients were divided into two groups: "Yes" group and "No" one. "Yes" group comprised 51 males (56.1 +/- 15.6 years old of mean +/- SD age) and 34 females (57.9 +/- 13.9 years old) and "No" group 170 males (57.7 +/- 14.3 years old) and 84 females (47.8 +/- 15.8 years old). The data were analysed for comparison between the two groups and the following results were obtained. Patients with benign and malignant oral, pharyngeal and laryngeal diseases were included in the "Yes" group with a significantly higher rate when compared to the patients with benign and malignant ear or nasal diseases. Patients in "Yes" group made significantly more complaints and judged to be significantly more neurotic and autonomic nerve dysfunctioning than those in "No" group. Therefore, diseases in the pharyngolaryngeal region more likely produces abnormal sensation in the throat as well as many other symptoms relating to the autonomic nerve function.

Adolescent↗

PubMed1989

[Effect of Impletol injection into paratonsillar tissue on abnormal sensation in the throat].

If the abnormal sensation, such as a lump or choking, in the throat was mainly caused by inflammatory changes in the palatine tonsils or their surrounding tissues and conveyed via vagal nerve branches distributing there, the sensation might be reduced by topically injected Impletol (Procaine and caffeine in saline solution), i.e. Impletol test for focal tonsillitis. One hundred patients with abnormal sensation in the throat were injected Impletol (Impletol group), 50 patients were injected saline solution alone (Saline group) and 50 patients had injection needle simply inserted into the peritonsillar tissues (Needle group). The Impletol group showed the best result and was followed by Saline group and then Needle group. Namely, the degree of sensation reduced by 80% or more in 38% of the Impletol group and by 50% or more in 62% of them. Those rates were 26% and 60% for Saline group and 28% and 52% for Needle group, respectively. Though the results were indicative of the effectiveness of the Impletol injection for the abnormal sensation in the throat, the difference among these three groups was not statistically significant.

Adult↗

PubMed1989

[Electron microscopic study of glycoconjugate in nasal mucosa of nasal allergy by lectin histochemistry].

Glycoconjugates in glandular and goblet cells of nasal mucosa were compared between normal and nasal allergy by using various horseradish peroxidase (HRP)-conjugated lectins; WGA, PNA, UEA-I and RCA-I. Specific sugar residues of glycoconjugates could be identified under electron microscope. Golgi's complex of the serous secretory cells in nasal allergic mucosa had positive staining in UEA-I. Goblet cells of nasal allergic mucosa were stained strongly in PNA, compared to normal mucosa, however, they were stained weakly in WGA. In conclusion, glycoconjugates in glandular and goblet cells seem to be changed in nasal allergy.

Glycoconjugates↗

PubMed1989

[Electron microscopic study of intercellular junction in nasal mucosa of nasal allergy by lectin histochemistry].

To explain of the mechanism of the enhanced nasal epithelial permeability to HRP in patients with nasal allergy, the inferior turbinate mucosa was removed from 6 normal adults and 7 adults with nasal allergy. Difference of the fine structure of the intercellular junction was compared between normal mucosa and mucosa of nasal allergy by electron microscope. Staining pattern of four kinds of HRP-conjugated lectin (HRP-WGA, PNA, UEA-I and RCA-I) was also studied by electron microscope. There was no significant difference in the intercellular space of the mucosa between the normal mucosa and mucosa of nasal allergy. In the epithelial cell membrane, pattern of HRP-lectin staining was almost similar in both groups. In normal nasal epithelium, the intercellular junction consisted of junctional complex; adherent junction, desmosome and gap junction. The intercellular space was approximately 150-250 A in width. The tight junction was located beneath the luminal surface of the epithelium, and belt-like continuation connecting the adjacent cells. It was concluded that enhanced permeability to HRP in nasal allergy was not morphologic changes of the intercellular junction and component and distribution of the glycoconjugates in epithelial cellular membrane, but this may be based on functional changes.

Glycoconjugates↗

PubMed1988

The relationship between antigen levels and middle ear inflammation in antigen-induced otitis media in the chinchilla.

The relationship between antigen levels in middle ear effusions (MEE) and the degree of middle ear inflammation was studied in an antigen-induced otitis media model, using chinchillas sensitized with human serum albumin (HSA). The degree of middle ear inflammation was evaluated by both tympanometric analysis, and cytological and biochemical analyses of the MEE. Middle ear inflammation develops after HSA challenge with a remarkable decrease in HSA levels in the MEE. This inflammation persists even when HSA levels are no longer detectable in the MEE. These findings show that local challenges with an antigen induce a certain degree of middle ear inflammation, which continues even after complete elimination of the antigen from the middle ear through an immunological defense mechanism.

Acoustic Impedance Tests↗

PubMed1988

Biochemical and cytological studies of immune-complex-induced otitis media in the chinchilla.

The pathogenesis of immune complex (IC)-induced otitis media in the chinchilla was studied through cytological and biochemical analyses of middle ear fluid (MEF) recovered after instillation of premade IC. The number to total leukocytes was 3.03 +/- 2.13 X 10(6)/cm3, and mainly involved neutrophils (72.3%) and macrophages (22.7%). The mean value of total protein, alpha 1-antitrypsin (alpha 1-AT) and alpha 2-macroglobulin (alpha 2-M) was 27.1 mg/ml, 189.5 and 75.2 mg/dl. The number of leukocytes had a significant correlation with the levels of total protein, alpha 1-AT and alpha 2-M (P less than 0.01). The inflammatory reaction induced by premade IC is characterized by an increased vascular leakage and an infiltration of leukocytes into the locus. The percentage of macrophages in the total leukocytes was larger in IC-induced otitis media than that in antigen-induced otitis media. These findings suggest that cellular events in the early stage of IC-induced otitis media may be different from antigen-induced otitis media.

Animals↗

PubMed1988

The effect of an orally administered proteolytic enzyme on the elasticity and viscosity of nasal mucus.

We have evaluated the effect of serratiopeptidase (SER), a proteolytic enzyme, on the elasticity and viscosity of the nasal mucus in adult patients with chronic sinusitis. SER was administered in a dose of 30 mg/day orally for 4 weeks. Nasal mucus was collected from the nasal cavities of each patient before (week 0) and 4 weeks after the start of the medication (week 4). The storage modulus (G') and the dynamic viscosity (eta') of each specimen of nasal mucus were determined by an oscillating sphere magnetic rheometer at frequencies of 0.5, 1, 5, 10 and 20 Hz at a constant temperature of 25 degrees C. The dynamic viscosity (eta') of the mucus at week 4 was significantly lower than that at week 0 (at frequencies of 5, 10 and 20 Hz). No significant differences were observed in the storage modulus (G') between the mucus at week 0 and week 4. SER reduced the viscosity but not the elasticity of the nasal mucus. These findings are discussed in relation to mucociliary clearance.

Administration, Oral↗