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Biomedical subjects

Y Sakakura

Publications and source records attributed to Y Sakakura.

At least 91 records · Page 5Linked to original sources
PubMed1996

Hypertrophic and metaplastic changes of goblet cells in rat nasal epithelium induced by endotoxin.

To elucidate the mechanisms of epithelial mucus hypersecretion in upper respiratory airway inflammation, we produced hypertrophic and metaplastic changes of goblet cells in rat nasal respiratory epithelium by intranasal instillation of endotoxin. Significant increase of hypertrophic goblet cells was induced in the septal epithelium transversely sectioned at the level of incisive papilla at 24 h after the intranasal instillation of 0.1 mg of endotoxin. This change was completed after 3 d of endotoxin instillations and recovered by normal epithelium 7 d after the last instillation. Total cell number and the number of basal and ciliated cells counted over 2 mm of basal lamina did not change; however, the number of goblet cells increased and that of nongranulated secretory cells decreased time-dependently after endotoxin instillations. Mitotic rates examined after a 6-h colchicine metaphase blockade were very low at any time point studied, and cell division did not play a major role in this process. These results indicate that endotoxin induces hypertrophic and metaplastic changes of goblet cells in rat nasal epithelium rather than a hyperplastic change, and this metaplasia is produced by direct conversion of nongranulated secretory cells into the goblet cells. Histochemical examination of this epithelium revealed that most of the mucus produced by these goblet cells was sulfomucin. Intraperitoneal injection of antirat neutrophil antiserum or cyclophosphamide depleted circulating blood neutrophils. Endotoxin-induced changes of goblet cells were significantly inhibited in these neutrophil-depleted rats, and intranasal instillation of elastase also induced hypertrophic and metaplastic changes of goblet cells.

Animals↗
PubMed1996

Analysis of T cell receptor beta chain repertoire in middle ear effusions.

In order to elucidate the immune response in otitis media with effusion (OME), the polymerase chain reaction was employed to examine T cells in middle ear effusions in patients with OME for utilization of T cell receptor (TCR) variable region genes. Specimens of RNA were extracted from 13 ears of 12 patients (9 children and 3 adults). Oligonucleotide primers specific for individual TCR Vbeta gene families were used to amplify TCR gene products in each sample. Although the number of Vbeta families utilized by each sample varied from 1 family to 21, a few significant trends emerged. Eleven ears out of 13 expressed Vbeta7, which was the most frequently utilized (84.6%) Vbeta family among the 24 Vbeta families. In 5 of the 13 samples, the number of Vbeta families utilized was restricted to 1, which was Vbeta7 in all 5 samples. This result indicates the possibility that Vbeta7-bearing T cells in the middle ear are responding to a certain common antigen in some cases of OME.

Adolescent↗
PubMed1996

Increased expression of histamine H1 receptor mRNA in allergic rhinitis.

BACKGROUND: Histamine plays an important role in producing nasal symptoms via histamine H1 receptor (H1R) in allergic rhinitis. It is reported that the minimum histamine concentration that induces sneezing is lower in allergic patients than in normal control subjects. Previous studies by binding assay on H1R gave divided results on whether the number of H1Rs is increased in allergic rhinitis or not. OBJECTIVE: The objective of this study was to examine if H1R mRNA expression is increased in patients with allergic rhinitis compared with normal healthy volunteers. METHODS: We extracted RNA from scrapings of inferior turbinate mucosa of 10 patients suffering from allergic rhinitis and 10 control subjects. As the H1R gene lacks introns, we treated RNA pellets by DNase to distinguish RNA from contaminating genomic DNA. Since amplification of H1R and beta-actin mRNA remained in an exponential phase at 35 cycles, H1R and beta-actin mRNAs were amplified for 35 cycles by reverse transcription-polymerase chain reaction (RT-PCR). The PCR products were hybridized with internal probes and band intensities were quantitated by a densitometer. RESULTS: The mean +/- SD of H1R/beta-actin ratio was 0.88 +/- 0.62 for the patients with allergic rhinitis and 0.29 +/- 0.17 for the normal subjects; the difference was statistically significant (P < 0.01). CONCLUSIONS: These data suggest that expression of H1R mRNA is increased in the nasal mucosa of the patients with allergic rhinitis.

Actins↗
PubMed1996

[The pollen count of Cryptomeria japonica and nasal symptom of Cryptomeria japonica pollinosis patients in recent three years in Mie Prefecture].

Airborne scattering of Cryptomeria japonica pollen depends on climate. Total pollen count and scattering pattern varies from one year to another. We counted Cryptomeria japonica pollen in February and March from 1993 to 1995 at several points in Mie Prefecture. One-third to two-thirds of all the patients who visited our clinic for the first time in the pollen period were occupied by allergic patients. The pollen count in 1995 amounted to 17943/cm2 at Tsu and 99512/cm2 in the whole prefecture, which is the largest in the past 12 years. The number of days in which patients severely suffered was correlated to the pollen count for the past three years. It was shown that nasal symptoms developed after certain amount of pollen had scattered, but the severity of symptoms thereafter largely depended on the total pollen count. At Tsu in 1995, we scarcely had pollen scattering in February but had tremendous amount of pollen count in March. Percentage of development of nasal symptoms among thirty patients was well correlated to the logarithm of accumulated pollen count. When accumulated pollen count reached to 100/cm2, half the patients developed symptoms. Most of the patients developed symptoms when it reached to 1000/cm2. Since there is a great interindivisual difference in when and how much patients have nasal symptoms, the choice of therapy should be based not only on the pollen count but also on the symptom and condition of each patient.

Adult↗
PubMed1995

Changes in expression of two endogenous beta-galactoside-binding isolectins in the dermis of chick embryonic skin during development in ovo and in vitro.

In order to elucidate the roles of metal-independent animal lectins, we systematically investigated changes in expression of 2 kinds of beta-galactoside-binding isolectins (MW 14 and 16 kDa) in the dermis of chick embryonic tarsometatarsal skin during the course of development. These lectins were immunohistochemically located at different stages of development both in ovo and in vitro by light and electron microscopy. Light-microscopic observation showed that while positive staining for the 14-kDa lectin was weak at days 8 and 10 it became intense after day 13. In contrast, staining for the 16-kDa lectin was intense at days 8, 10, and 13, but it became weak after day 17 when keratinization of the epidermis was completed. Immuno-electron-microscopic observation revealed that both the 14 and 16-kDa lectins were located on the basement membrane, in the extracellular matrix, and in both the cytoplasm and the nucleus of dermal fibroblasts. Distribution of the 2 isolectins was also examined in cultured skin explants in vitro. The results were almost the same as those obtained in ovo when the skin explant was keratinized in the presence of hydrocortisone. However, in the skin explant where keratinization was prevented and mucous metaplasia was induced by the addition of vitamin A, the distribution of the 14-kDa lectin in the epidermis was significantly affected. These results indicate that (1) the expression of the 2 isolectins is differently regulated in both the dermis and epidermis, (2) the 16-kDa lectin is involved in the early stage of the formation of the dermis and the basement membrane and is replaced by the 14-kDa lectin as keratinization of the epidermis occurs, and (3) the expression of the 2 isolectins in the dermis is not significantly affected by the induction of mucous metaplasia, in contrast to their drastic changes in the epidermis.

Animals↗
PubMed1995

Effect of oxatomide nasal spray on experimental allergic rhinitis in guinea pigs and rats.

We investigated the effect of topically applied oxatomide, an antiallergic agent, on the assault of allergic rhinitis in actively sensitized guinea pigs. Topical application of oxatomide nasal spray (0.025%) reduced the severity of allergic rhinitis which was assessed by determining dye leakage and histamine released to the nasal cavity of guinea pigs. Furthermore, oxatomide nasal spray treatment significantly prevented the increase in dye leakage induced by histamine administration in guinea pigs and rats. These results indicate that the topical application of oxatomide inhibits both the release and the action of histamine. Therefore, oxatomide nasal spray may be beneficial for treatment of allergic rhinitis.

Administration, Intranasal↗
PubMed1995

Effect of histamine on nasal epithelial permeability to horseradish peroxidase in allergic guinea pigs.

The effect of histamine and antigen on the permeability of nasal mucosa to macromolecules in allergic guinea pigs was investigated with a histochemical technique using horseradish peroxidase (HRP). We found that the ratio of intercellular spaces penetrated by HRP to the total number of intercellular spaces of the nasal epithelium in nonallergic groups was increased by histamine challenge dose-dependently. The HRP reaction products in the intercellular spaces in allergic groups were significantly increased by challenge with histamine at 5.4 x 10(-4) mol/L and 5.4 x 10(-2) mol/L, in contrast to nonallergic groups. We conclude that histamine increases nasal mucosal permeability, and this effect is most likely mediated by a functional change in the epithelial tight junctions.

Animals↗
PubMed1995

Ability of histamine to increase nasal mucosal permeability to macromolecules in guinea pigs.

The effect of histamine on nasal mucosal permeability against an antigen was investigated by using modified passive cutaneous anaphylaxis (PCA) reactions in normal and actively sensitized guinea pigs. The administration of a dinitrophenyl-coupled Ascaris (DNP-Ascaris) solution as an antigen into the nasal cavity caused PCA reactions in the dorsal skin of normal guinea pigs. The administration of histamine into the nasal cavity before the antigen treatment significantly enhanced the anaphylactic responses. The PCA reactions did not occur when ovalbumin (OA) was administered intranasally in normal guinea pigs. In guinea pigs sensitized against DNP-Ascaris, however, PCA reactions to anti-OA antiserum were elicited by the intranasal administration of OA. The intranasal administration of histamine before the antigen treatment also enhanced anaphylactic responses in sensitized guinea pigs. These results indicate that histamine increases nasal mucosal permeability and that this may be one of the causes of nasal hypersensitivity in nasal allergy.

Allergens↗
PubMed1995

The effect of KW-4679, an antiallergic drug, on experimental allergic rhinitis in guinea pigs: effects on nasal blockage.

We investigated the effect of KW-4679 (Z-11-(dimethylaminopropyliden)-6,11-dihydrodibenzoxepin-2-a cetic acid hydrochloride), an antiallergic agent, on the nasal blockage induced by antigen challenge into the nostrils of actively sensitized guinea pigs. The change of the nasal cavity volume caused by nasal mucosal swelling after antigen challenge was measured by acoustic rhinometry. Oral administration of KW-4679 (0.01-10 mg/kg) significantly inhibited the decrease in the nasal cavity volume at 10 min, 30 min and 6 hr after antigen challenge. Ketotifen (1-10 mg/kg, p.o.) also inhibited the decrease in the nasal cavity volume after antigen challenge. These results indicate that KW-4679 may be useful for the treatment of allergic rhinitis.

Animals↗
PubMed1994

Nasal mast cells in experimentally induced allergic rhinitis in guinea-pigs.

The kinetics of mast cell accumulation in the nasal mucosa during allergen exposure were investigated in the animal model of experimentally induced allergic rhinitis. Guinea-pigs were divided into an unsensitized control group and five sensitized groups each containing five animals. Five sensitized groups were immunized intraperitoneally with ovalbumin, followed by intranasal administration of ovalbumin in each of four groups for 1, 2, 3 and 4 weeks, respectively. There were significant increases in the number of mast cells in the epithelium after 2 and 3 weeks in the groups receiving intranasal ovalbumin. No significant changes were detected in the lamina propria and the total number of mast cells. In the lamina propria, the distance between a mast cell and the basement membrane was significantly decreased in the groups after 2, 3 and 4 weeks of intranasal administration. These findings suggest that an infiltration of mast cells from the lamina propria to the epithelium occurred after 2 weeks of intranasal administration of allergen. An electron microscopic study showed no mast cells at the luminal surface of the epithelium and the majority of mast cells lying around the basal cells. This finding suggests that the allergen must penetrate into the epithelium in order to interact with mast cells in guinea-pig nose.

Animals↗
PubMed1994

Quantitation and immunocytological identification of interleukin-1 in nasal polyps from patients with chronic sinusitis.

Immunoreactive interleukin-1 (IL-1) alpha and beta levels in nasal polyp (NP) extracts were measured from 22 adult patients with chronic sinusitis (CS) in order to determine their significance in the pathogenesis of NP. The NP sample was separated into mononuclear and polymorphonuclear fractions. In the mononuclear fraction, the mean value of IL-1 beta was 21.5 pg/ml/g, which was significantly higher than that of IL-1 alpha (8.4 pg/ml/g, p < 0.01). In younger adults, the IL-1 alpha and IL-1 beta levels were 21.2 and 59.4 pg/ml/g, which were significantly higher than those in older CS patients (p < 0.01). There was a significant reverse correlation between patient's age and IL-1 beta levels in the mononuclear fraction (r = -0.509, p < 0.01). Immunoreactive IL-1, mainly IL-1 beta, was identified in the cytoplasmic area of monocytes. A certain amount of immunoreactive IL-1 is produced in mononuclear leukocytes, particularly activated monocytes, and IL-1 beta production is greater than IL-1 alpha. In younger adult CS patients, NPs contain larger amounts of IL-1 beta in monocytes, compared to those of older patients.

Adolescent↗
PubMed1994

Expression of phenotypic markers during regeneration of rat tracheal epithelium following mechanical injury.

We examined epithelial regeneration in mechanically injured rat trachea using phenotypic markers that identify unique differentiated stages of epithelial cells. Following a focal denuding wound, the cells from the adjacent nonwounded epithelium flattened and migrated into the wounded site during the first 12 h. At 24 h, these cells dedifferentiated into poorly differentiated (PD) cells that did not precisely resemble any of the mature tracheal cells. Proliferation of PD cells produced a multilayered epithelium by 48 h. Mitotic activity, measured as mitotic rate (MR) following a 6-h colchicine metaphase blockade, was high at 24 h (MR 23.4%) and 48 h (MR 24.0%). These PD cells expressed keratin 14 and Griffonia simplicifolia I-isolectin B4 (GSI-B4) lectin binding sites, which are specific for basal cells in normal epithelium but did not react with secretory or ciliated cell markers. At 72 h, MR fell to 1.8% (control MR 0.38%). The wound was covered with a pseudostratified epithelium; secretory cell markers were present at the apex of differentiating columnar cells, and a few preciliated cells expressing ciliated cell markers appeared. Basal cells also became distinctly recognizable and expressed keratin 14 and GSI-B4 binding sites. Newly appearing secretory or ciliated cells also expressed these markers but lost them gradually as they acquired new sets of specific markers. During epithelial regeneration after mechanical injury, "dedifferentiation," "proliferation," and "redifferentiation" of epithelial cells occurred, and the PD cell was pivotal in this process.

Animals↗
PubMed1994

Distribution of substance P immunoreactive nerve fibers in the tracheal submucosal gland of cats.

Immunohistochemistry combined with electron microscopy was employed to investigate the distribution of substance P-immunoreactive (SP-IR) nerve fibers in the tracheal submucosal gland of cats. The SP-IR nerve fibers were found to form a network around the glands. Numerous varicosities were also detected within the basement membrane of the acini and secretory tubules. All the intraglandular varicosities showed close spatial contact with serous cells, mucous cells, and myoepithelial cells. Our findings suggest that substance P-induced mucus secretion from tracheal submucosal glands in cats may be caused not only by a glandular contractile response of myoepithelial cells, but also by direct stimulation to both serous and mucous cells.

Animals↗
PubMed1994

Interleukin-8 gene expression in middle ear effusions.

Interleukin-8 (IL-8), a monocyte- and macrophage-derived cytokine, displays potent chemotactic-activating properties toward neutrophils, and thus may contribute to the pathogenesis of otitis media with effusion (OME). The objective of this investigation was to demonstrate the expression of the IL-8 gene in middle ear effusion (MEEs) of children and adults with OME. Ribonucleic acids (RNAs) were extracted from MEEs from 16 ears of 13 pediatric patients and 12 ears of 12 adult patients with OME. The RNAs were reverse-transcribed and amplified by the polymerase chain reaction. Interleukin-8 transcripts were detected in 75% of both pediatric (12/16) and adult MEEs (9/12). The levels of expression of IL-8 and beta-actin messenger RNAs were quantitated. No significant difference was observed in IL-8/beta-actin ratios between pediatric MEEs and adult MEEs. These data suggest that IL-8 may contribute to neutrophil involvement in both pediatric and adult OME.

Actinin↗
PubMed1994

[Evaluation of throat discomfort with visual analogue scale (VAS)].

We adopted a visual analogue scale (VAS) to evaluate discomfort like the sensation of a choking lump in the throats of 92 patients (24 male and 68 female, 17-80 years of age) who consulted us complaining of the sensation. The VAS consisted of a 100 mm long horizontal straight line defined by anchors with verbal labels: the left end point (0 mm) indicated no throat discomfort, the right end point (100 mm) overwhelming throat discomfort. We determined the VAS score (1 mm = 1) by measuring the distance from the left end point to the mark made by the patient. On the first day of the study, the patients evaluated the sensation with the VAS alone. One, two and three weeks later they evaluated the sensation with the scale, and at the same time, they were asked to compare the strength of the existing sensation with that on the first experimental day and to express the percent change in the sensation. The latter data were used for calculation of the predicted VAS score. It was neither difficult nor time-consuming for the patients, some of whom were fairly elderly, to display the strength of the sensation on the scale. The VAS score on the first day of the study for each patient ranged from 6-92, and the mean and the standard deviation were 44.6 and 21.0, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Antigen (DNP-As)-induced allergic rhinitis model in guinea pigs.

In guinea pigs, an IgE antibody was produced by intraperitoneal injection of antigen (DNP-As) containing Al(OH)3 and booster inhalation of the antigen into the nasal cavity. Experimental allergic rhinitis was induced by the perfusion of antigen solution into the nasal cavities of actively sensitized guinea pigs. Severity of allergic rhinitis was assessed by determining release of histamine and leakage of dye into the nasal cavity. The antigen-induced release of histamine was significantly increased at 0 to 15 minutes following antigen administration but then decreased with time. The antigen-induced leakage of dye was sustained for 60 minutes after administration of the antigen. These results suggest that the DNP-As-induced allergic rhinitis model in guinea pigs is instrumental in evaluating the effect of various factors on allergic rhinitis.

Animals↗
PubMed1994

Localized aerosol hyperthermia in patients with nasal allergy.

A double-blind study was performed to evaluate the efficacy, the safety and the usefulness of localized aerosol hyperthermia (LAH) in 57 patients with nasal allergy. We used two localized aerosol hyperthermia devices, the equipment (AH) with an insufflated aerosol of 43 degrees C and a placebo device (PH) with aerosol of 32 degrees C. In the evaluation of clinical efficacy, efficacy rates were 46.4% in AH and 3.7% in PH during 2 weeks, respectively, and 53.3% in AH and 7.7% in PH during 4 weeks, respectively. There was a significant difference (p < 0.01) between the two treatment groups. The usefulness rates were 63.3% in AH and 7.4% in PH for patients with nasal allergy, showing a statistically significant difference (p < 0.01). No patients dropped out of the study due to adverse effects. These results suggest that the LAH is a very useful instrument for the treatment of nasal allergy.

Aerosols↗