Biomedical subjects

Y Sakakura

Publications and source records attributed to Y Sakakura.

At least 19 recordsLinked to original sources

PubMed1992

Nasal mucociliary transport of chronic sinusitis in children.

Nasal mucociliary function is one of the most important and indispensable mechanisms of the respiratory tract, providing protection against the atmospheric environment. We previously found mucociliary dysfunction in the noses of adult patients suffering from chronic sinusitis. In this study, using the saccharin method, we determined nasal mucociliary function in normal children and in children with chronic sinusitis. The mean (+/- SD) value of saccharin transit time in the nose was 28.2 +/- 19.9 minutes in patients with chronic sinusitis, this being significantly slower than that in the control group of children. The incidence of abnormally slow nasal mucociliary transport time (> 30 minutes) in patients was significantly higher than in controls of the same age. Mucociliary dysfunction may initiate a vicious cycle of self-mediated inflammation and may be important in recovery from chronic respiratory inflammation.

Adolescent↗

PubMed1992

Neutrophil elastase and its complex with alpha 1-antitrypsin in the pathogenesis of chronic suppurative otitis media.

Neutrophil elastase (NE) and its complex with alpha 1-antitrypsin were quantified in ear discharges from 15 patients with chronic suppurative otitis media (CSOM), and their levels were compared to those in middle ear effusions from 10 pediatric patients with chronic otitis media with effusion (OME). The localization of immunoreactive NE was also examined by immunocytologic study. The mean value of total NE was 161.8 +/- 29.5 micrograms/mL in CSOM, which was significantly higher than that in OME (16.5 +/- 6.7 micrograms/mL). The mean value of NE-alpha 1-antitrypsin complex was 13.7 +/- 8.8 micrograms/mL in CSOM and 7.8 +/- 4.0 micrograms/mL in OME. There was no significant difference between culture-positive and culture-negative samples in CSOM. Immunoreactive NE could be observed in the neutrophils of ear discharges, and extracellular release of NE was also observed. Ear discharges in CSOM contain a considerable amount of uncomplexed NE, of which the level does not depend on active bacterial infections. Uncomplexed NE seems to play a role in the chronicity of CSOM.

Adolescent↗

PubMed1992

Newcastle disease viral infection in chicken nasal turbinate and maxillary sinus.

Newcastle disease virus (NDV) B strain was inoculated intranasally and intrasinusly into unanesthetized chicken which were maintained on a standard commercial mash chicken diet until the age of 21 days after hatch. The lesions induced by NDV following intranasal inoculation usually produced a selective destruction of significant portions of the inner surface of the turbinate scroll, but sinus lesions, though sometimes present in NDV infection, were not common. The chicken sinus was infected by intrasinus inoculation. These results were supported by the amount of virus and mucociliary transport time in the turbinate and sinus. It is suggested that mucus hypersecretion of ostial gland and/or mucociliary activity in the sinus be one of the most important factors in protecting against chicken sinus infection.

Animals↗

PubMed1992

[Surgical treatments of adult chronic sinusitis--a study by questionnaire from 434 hospitals in Japan].

Information concerning surgical treatment of adult patients with chronic sinusitis was obtained through questionnaires from 434 hospitals in Japan. The hospitals were authorized for an in-service otorhinolaryngological training institute by the Oto-Rhino-Laryngological Society of Japan. The questionnaires were sent to the hospitals in December, 1989, and answers were obtained from 370 hospitals within 2 months, an 85.3% response rate. The following results were obtained. In 96.2% of the hospitals, permaxillary sinus surgery was performed on patients whose maxillary and ethmoid lesions were severe. With moderate lesions of both the maxillary and ethmoid sinuses, permaxillary sinus surgery and endonasal sinus surgery were performed in 76.0% and 24.9%, respectively. Application of an endoscope for sinus surgery was reported by 89 hospitals. In January, 1990, a further survey was sent to the 89 hospitals where endoscopic sinus surgery was performed. Questionnaire responses were obtained from 75 hospitals. Rigid endoscope was used most frequently and operative microscope was also used. Endoscopy was applied to all of the sinus surgery procedures in 21.6%, and to a portion of the procedures in 74.3% of the hospitals. About 50% of the hospitals performed endoscopic surgery in fewer than 30% of sinus surgery cases. When questioned as whether endoscopic surgery had been successful, 42.6% said yes, 10.7% said no, and 42.6% were unsure.

Adult↗

PubMed1992

[The quantitation of Pseudomonas aeruginosa elastase in suppurative chronic otitis media using a sensitive ELISA method].

A sensitive sandwich ELISA method has been developed in order to quantitate the Pseudomonas aeruginosa elastase (PE) of ear discharge from chronic suppurative otitis media (CSOM) patients. Samples were incubated with EDTA-2Na before ELISA in order to inhibit the PE activity which hydrolyzes anti-PE IgG antibody into smaller molecular fragments. Quantitation of PE in middle ear effusions (MEE) from 10 patients with chronic otitis media with effusion (OME) were also performed. In CSOM, 12 of 14 samples revealed a significant amount of PE from 0.6 microliter/ml to 62.1 microliters/ml, which was significantly higher than those in MEE (p less than 0.05). In MEE, 8 of 10 samples were under the detection limit. Two samples in CSOM with Pseudomonas aeruginosa infection had high levels of PE. The quantitation was linear, with a concentration from 5 ng PE/sample to 500 ng PE/sample. This ELISA system is a sensitive method for quantitation of PE requiring only very small samples.

Adolescent↗

PubMed1992

Endogenous epidermal growth factor regulates the timing and pattern of embryonic mouse molar tooth morphogenesis.

The tooth organ provides a model for discrete patterns of morphogenesis over short periods of developmental time. Studies were designed to test the hypothesis that endogenous epidermal growth factor (EGF) functions to regulate multiple cusp molar tooth morphogenesis during embryonic mouse development. The relative levels of endogenous EGF and EGF receptor (EGFR) transcripts were determined in both enamel organ epithelia and dental ectomesenchyme by reverse transcription-polymerase chain reaction (RT-PCR) assays. EGF and EGFR were localized by immunohistochemistry; both antigenic determinants were demonstrated on the same odontogenic cells in cultured tooth explants. To examine EGF-mediated signal transduction, cap stage mouse molar tooth organs (E16) were cultured in serumless, chemically-defined medium as either (i) controls, or supplemented with (ii) tryphostin (an EGF receptor kinase inhibitor), (iii) tyrphostin plus exogenous EGF, and (iv) exogenous EGF. Antisense oligodeoxynucleotide (ODN) strategy was used to investigate the functions of endogenous EGF employing (i) non-treated control, (ii) sense ODN control, (iii) antisense ODN, (iv) exogenous EGF, (v) sense ODN with exogenous EGF, and (vi) antisense ODN with exogenous EGF. Tyrphostin inhibited DNA synthesis and produced a significant decrease in the volume of the explants. These effects were recovered by addition of exogenous EGF. Antisense ODN inhibition resulted in abnormal cusp formations, decreased DNA synthesis, total DNA, RNA and protein content, and decreased stellate reticulum and tooth explant volumes. The decreased tooth size was not uniform, the most pronounced effect was in the stellate reticulum. This pattern of changes was not seen when antisense ODN treatment was supplemented with exogenous EGF. These results suggest that during cap stage of odontogenesis endogenous EGF acts to stimulate DNA synthesis, which increases the cell number of specific phenotypes within the enamel organ epithelia, and thereby regulates molar tooth morphogenesis.

Animals↗

PubMed1992

Gene expression, signal transduction and tissue-specific biomineralization during mammalian tooth development.

Tooth development provides a paradigm for intrinsic molecular controls for cell- and extracellular matrix (ECM)-mediated biomineralization. The intent of this review is to evaluate the sequential timing and positional information prerequisite for tissue-specific biomineralization. Recent investigations suggest that 1,25-dihydroxyvitamin D3 functions to up-regulate VDR (vitamin D receptor) that in turn could induce structural gene products, including calcium-binding proteins and several ECM proteins (e.g., enamelins, amelogenins, dentine sialoglycoproteins (DSP) and dentine phosphoproteins (DPP)), resulting in dentine and enamel formation. Inhibition of regulatory gene products and/or their receptors likely results in hypoplastic and/or hypomineralized ECM as a direct consequence of down-regulated (1) transcription and/or translation of structural and regulatory genes, (2) posttranslational modifications, (3) and/or decreased calcium transport to the forming dentine and enamel matrices. Advances in serumless in vitro culture methodology; computer-assisted access to nucleic acid sequences for probes to define when, where, and how many specific regulatory and structural gene products are expressed; antisense oligodeoxynucleotides to inhibit specific translation; and microtechniques to analyze biomineralization all provide additional avenues to investigate tissue-specific biomineralization.

Animals↗

PubMed1992

[Maxillary prosthesis for better QOL--early setting and faster construction of maxillary prosthesis].

The maxillofacial prosthesis (MFP) is well accepted as one of the modalities to ameliolate the postsurgical crippling in the patients with maxillary malignancy. In this report, we analyzed 55 primary cases of MFP out of 100, from July, 1981 to July, 1987 in terms of the time of start after operation, and the duration and procedure of the MFP-making. MFP-making set about within 4 weeks in 35% of patients, 8 weeks in 25%, 12 weeks in 22%, and more than 12 weeks in 18%. The completion of MFP-making averaged 10 days. As a result of simplifying of MFP-making, we shortened a period requiring MFP-making within 3 days in recent 10 cases. There were no adverse effects of early wear of MFP after operation. We believe that early wear of MFP after operation improve the quality of life of patients with maxillary malignancy and considered that wear of MFP is not the completion of treatment, but is one of the procedures of treatment for the patients undergone maxillectomy.

Adolescent↗

PubMed1991

Human breast carcinoma cDNA encoding a galactoside-binding lectin homologous to mouse Mac-2 antigen.

A galactoside-binding lectin (Mr 29,000) has previously been identified in rat, mouse and human tissues. It is an abundant cell-surface component of inflammatory macrophages and their major non-integrin laminin-binding protein. It has also been found in the nucleus of other cell types. Here, we report the cloning and sequencing of a cDNA encoding the human galactoside-binding lectin from a breast carcinoma. The clone encodes a protein of 250 amino acids (aa) that is over 80% identical to its mouse and rat counterparts. The aa sequence has an N-terminal and a C-terminal, 'carbohydrate-binding', domain. The N-terminal domain consists of two parts. The first 41 aa are homologous to a transcription factor, i.e., the serum response factor. The adjacent part (aa 42-106) contains an unusual repeating element, that occurs seven times in human protein compared to nine times in rat and mouse. The C-terminal 'carbohydrate-binding' domain (aa 115-250) shows homology to L-14, another galactoside-binding lectin.

Amino Acid Sequence↗

PubMed1991

A technique for quantitative cytology of nasal secretions.

To quantitatively analyze cellular elements in mucopurulent nasal secretions from patients with chronic paranasal sinusitis, we studied five mucus-liquefying agents--dithiothreitol (DTT), ethylenediaminetetraacetic acid tetrasodium salt, propylene glycol, serratio peptidase and urea--with Hanks' balanced salt solution used as a control. Agents were compared for the number of cells, the mucus-liquefying effect and the staining characteristic of cells in cytocentrifuge-prepared smears. The results indicated that the treatment of nasal secretions with 10 mM DTT provides more clear and detailed cytological preparations for quantitative cytology of nasal secretions.

Cell Count↗

PubMed1991

ELISA to determine immunoreactive Pseudomonas aeruginosa elastase in chronic suppurative otitis media.

A sensitive sandwich ELISA has been developed to measure the levels of Pseudomonas aeruginosa elastase (PE) in ear discharges from chronic suppurative otitis media (CSOM) patients. Preincubation of the sample with EDTA-2Na before ELISA was employed to inhibit PE activity which hydrolyzes the anti-PE IgG antibody into a smaller molecular form. The PE levels of 10 middle ear effusions (MEE) from chronic otitis media with effusion were also measured. In CSOM, 9 of 10 samples had significant PE levels, ranging from 6.8 to 62.1 micrograms/ml, which were significantly higher than those in MEE (p less than 0.01), the majority of which was below the detection limit. Two samples of CSOM with the P. aeruginosa infection showed high PE levels. This sandwich ELISA for the measurement of PE is a very sensitive method requiring only a small sample amount.

Enzyme-Linked Immunosorbent Assay↗

PubMed1991

Short-term mineralization of dentin and enamel in the mouse embryonic molars cultured in serum-free, chemically-defined medium.

The present study was designed to demonstrate the short term mineralization of dentin and enamel, and to investigate the effects of sodium beta-glycerophosphate (Na-beta-GPO4) on calcification in a serum-free, chemically-defined medium. The first mandibular molars at the bell stage dissected from 18-day-old mouse embryos were used as explants, which were cultured by an improved flotation method. Calcification of enamel in the 18-day-old embryonic molars occurred within the 6th day of culture. In another experiment, the molar germs were cultured in a serum-free, chemically-defined medium supplemented with 1, 5 and 10 mM Na-beta-GPO4. Promotion of tooth mineralization was recognizable at very low concentrations, such as 1 mM Na-beta-GPO4, in 18-day-old embryonic tooth germs. The culturing system reported here shortens the time required for dentin and enamel calcification to one half or one third of that reported previously and therefore should prove useful for examining regulations for cytodifferentiation and morphogenesis in tooth germs and the mineralization of dentin and enamel.

Ameloblasts↗

PubMed1991

Role of transepithelial ion transport as a determinant of mucus viscoelasticity in chronic inflammation of the maxillary sinus.

Chronic sinusitis is a chronic inflammatory disease with fluid retention, most frequently in maxillary sinus. We measured both viscoelasticity of maxillary sinus fluid and bioelectric properties of maxillary mucosa in an attempt to correlate the mucus viscoelasticity with bioelectric properties. During sinus surgery, maxillary sinus fluid and maxillary mucosa were obtained from 15 patients with chronic sinusitis. Viscoelasticity was measured with an oscillating sphere magnetic rheometer within 24 h after sampling. Potential difference and short circuit current of maxillary mucosa mounted in Ussing chambers were measured before and after exposure of mucosal surface to amiloride. Both elasticity and viscosity showed significant positive correlation with percent inhibition of short-circuit current by amiloride. Our results indicate that the ion transport process plays a role in the determination of viscoelasticity of maxillary sinus fluid in chronic sinusitis.

Adult↗

PubMed1991

A quantitative study of the ciliary area of experimental otitis media with effusion in cats.

A quantitative electron microscopic study was performed to determine the extent of the ciliary surface area of the middle ear epithelium in cats. In normal cats, 97.8% of the middle ear mucosa in the hypotympanum and 45.9% in the upper part of the bulla were covered by cilia. Eustachian tube obstruction (ETO) significantly reduced the ciliary area to 73.1% in the hypotympanum and to 16.2% in the upper part of bulla at 1 week after ETO. Instillation of Escherichia coli lipopolysaccharide (LPS) or cat polymorphonuclear leukocyte (PMN) lysate into the middle ear cavity followed by ETO did not reduce the ciliary area, compared with ETO induced alone. Our results indicate that ETO reduces the ciliary area of the middle ear mucosa and that LPS or neutrophils do not enhance reduction of the ciliary area compared to ETO induced alone in this experimental condition.

Animals↗

PubMed1991

Rheological properties of middle ear mucus in relation to goblet cell population in cat.

Seventeen mucoid middle ear effusions were collected from the tympanic cavity of 15 cats 1 or 2 weeks after tubal obstruction. Middle ear mucosa was also taken both from the tympanic cavity and bulla, and the number of goblet cells was counted. Both elasticity (G') viscosity (eta') of the mucoid effusion were determined with an oscillating sphere magnetic rheometer and compared with goblet cell count. There was a significant correlation between G' and goblet cell population in the tympanic cavity. A similar significant correlation was observed between eta' and goblet cells. The G' and eta' values of the mucoid mucus were much higher than the optimal viscoelasticity for mucociliary transport. Results indicate that the mucus obtained in this study mainly originated from the goblet cells, and that its viscoelasticity was beyond ideal values for mucociliary transport.

Animals↗

PubMed1991

Rheological and biochemical properties of middle ear effusions from experimental otitis media in cats.

Both rheological and biochemical analyses were performed on middle ear effusions (MEEs) from cats with experimental otitis media with effusions (OME) induced by obstruction of the Eustachian tube. This study was undertaken in order to clarify the factors determining rheological properties (elasticity and viscosity) of MEEs. The viscoelasticity of the effusions had a positive significant correlation to fucose/total protein concentration (TPC), and a negative correlation to cathepsin B level/TPC. No correlation was observed between albumin level/TPC and viscoelasticity. These results indicate that in cats the rheological properties of MEEs depend on the level of secretory glycoproteins in MEEs and on the severity of inflammation in the early stage after tubal obstruction.

Albumins↗

PubMed1991

The relationship between proteases activity and glycoprotein levels in middle ear effusions from experimental otitis media in cats.

The relationship between lysosomal proteases activity (elastase and cathepsin B) and levels of mucous glycoproteins in middle ear effusions (MEEs) was studied using a cat model of otitis media with effusion (OME) induced by Eustachian tube obstruction (ETO). The ratio of cathepsin B activity to total protein concentration (TPC) in MEE was 25.6 +/- 19.4 RFU/g x dl-1 at 1 week after ETO, and increased with the duration of OME. The ratio of elastase activity to TPC had a significant correlation to total leukocyte count. The ratio of fucose levels to TPC, which is one of the parameters reflecting levels of mucous glycoprotein, at 1 week after ETO was significantly higher than that at both 2 and 4 weeks after ETO. The percentage of glycoprotein levels absorbed to wheat germ lectin was highest at 1 week after ETO, and decreased with the duration of OME. In conclusion, mucous glycoproteins in cat occupy a larger portion of glycoproteins in MEE at the early stage of OME, and elastase and other lysosomal proteases may play a role in both stimulation of mucin release from goblet cells and mucin degradation. The balance of these processes seems to be a key factor determining mucin levels in MEEs.

Albumins↗

PubMed1991

Effects of endotoxin and neutrophil lysate on experimental otitis media with effusion in cats.

Middle ear effusion (MEE) from otitis media with effusion (OME) contains large amounts of chemical mediators and substances from bacteria, which may act on the mucosa itself and cause further changes in the inflamed mucosa and MEE. To clarify the effects of such substances in MEE, we instilled endotoxin (LPS) or allogeneic neutrophil lysate (NL) into the middle ear cavity of OME induced by Eustachian tube obstruction (ETO). ETO + LPS and ETO + NL groups showed retention of a large amount of MEE as a characteristic difference between ETO alone group and these groups. The instillation of LPS into the middle ear cavity of the ETO model significantly increased the number of total cells and the ratio of the concentrations of albumin to total protein in MEEs. The instillation of NL significantly increased the number of goblet cells in the middle ear. These facts indicate that the pathology of OME may change in response to various factors added to MEE. Hence, we propose that a vicious circle of self-mediated inflammation is a possible causative factor for chronic OME.

Animals↗