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Biomedical subjects

Y Sakakura

Publications and source records attributed to Y Sakakura.

At least 271 records · Page 15Linked to original sources

Effects of middle ear effusion on neutrophil function.

The neutrophil chemotactic activity of middle ear effusions (MEE) was measured in patients with pediatric chronic, adult chronic, and acute otitis media with effusion (OME). Chemotactic activity differed significantly among the three groups of otitis media in the following order: adult chronic less than pediatric chronic less than acute. Culture-positive effusions had higher chemotactic activity than did those that tested culture negative, suggesting that bacterial infection is related to neutrophil chemotactic activity. The chemotactic function of normal peripheral neutrophils was not enhanced by preincubation with MEE, but their bactericidal function was enhanced. In conclusion, bacterial infection in the middle ear is one of the major determining factors of neutrophil infiltration during OME, and MEE enhances the bactericidal function of neutrophils.

Acute Disease↗

Superselective intraarterial chemotherapy in combination with irradiation: preliminary report.

Since 1984, a new method for the intraarterial administration of antineoplastic drugs, termed "superselective intraarterial chemotherapy," has been used in combination with simultaneous irradiation in the treatment of 49 patients with squamous cell carcinoma of the head and neck. Under the fluoroscope, a retrograde catheter is inserted into the superficial temporal artery and the tip is led selectively into the main feeding artery of the tumor. In our series of 49 patients, catheter-related complications occurred in only 12.5%. Forty-five patients (91.8%) completed more than 80% of the planned irradiation dosage. The therapeutic effect was excellent. The initial response rate was 100%. Systemic toxicity was uncommon, but local mucositis was frequent in the infused area. These results demonstrate that this new combined therapy is easy, safe, effective, and confers the highest possible initial response rate.

Adult↗

Lysosomal proteases and protease inhibitors in nasal allergy and non-atopic sinusitis.

Patterns of protease activity and levels of protease inhibitors were analyzed in both nasal secretions and tissue extracts from patients with nasal allergy and non-atopic sinusitis to investigate the role of proteases in the inflammatory reaction. Protease activity was measured using specific methyl-coumaryl-7-amide substrates. The pattern of protease activity in the nasal secretions of chronic sinusitis patients was similar to that in neutrophil lysate and quite different from that in plasma. Both gluthatione activation testing and inhibition testing using synthetic inhibitors revealed that the majority of proteases in both secretions and tissues are lysosomal thiol proteases such as cathepsins B and L. Neutrophilic elastase is also a major protease in nasal secretions. In acute sinusitis, both protease activity and inhibitor levels were very high, suggesting an interaction between proteases and inhibitors. Cathepsin B and B-like thiol proteases appear to play a key role in prolonging chronic inflammation against the healing process, due to their resistance to plasma inhibitors and the shortage of thiol protease inhibitors. Protease activity in the secretions of nasal allergy patients was very weak, and the reaction between proteases and inhibitors appeared to be weak.

Adult↗

A simple measurement of parotid salivary flow using material quick absorber.

We applied Material Quick Absorber (Inami Co Ltd, Tokyo, Japan), a small triangular paper strip made mainly from viscose and used for fluid absorption during surgery, to collect right resting parotid saliva directly from Stensen's orifice and estimated nonstimulated parotid salivary flow by weighing the saliva absorbed in a given period of time. We assayed this method in 53 patients with dry mouth and/or throat and in 115 healthy young and elderly control subjects. The median salivary flow rates in male and female patients were 18 mg/min (almost equal to 0.018 mL/min) and 11 mg/min, respectively, significantly lower (P less than .05 for men, P less than .01 for women) than those obtained from young male (36 mg/min) and female (34 mg/min) controls and consistent with previously reported physiologic flow rates obtained by means of the "cup method." Although the median flow rate for elderly male controls (35 mg/min) was rather close to that of young male or female controls, there was no significant difference in flow rates between elderly male controls and male patients. On the other hand, in female control subjects, a significant decrease (P less than .05) in salivary flow was shown with aging. Repeated 3-minute measurements (eight times at 5- to 6-minute intervals) with this method in 10 healthy younger male volunteers showed that the coefficient of variance in the same subject ranged from 14.1% to 57.2% and that the larger the mean flow rate the smaller the coefficient of variance (P less than .05 by simple regression analysis).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Interleukin-8 gene expression in chronic sinusitis.

PURPOSE: Interleukin-8 (IL-8), a monocyte-derived and macrophage-derived cytokine, displays potent chemotactic activating properties toward neutrophils and thus may contribute to the pathogenesis of chronic sinusitis. The object of this investigation was to show the expression of the IL-8 gene in chronic sinusitis by Northern blot analysis and a reverse transcription-polymerase chain reaction (RT-PCR). MATERIALS AND METHODS: For Northern blot analysis, RNAs were extracted from maxillary mucosa and nasal polyps from two patients with chronic sinusitis, respectively, and from the inferior turbinate of a nasal allergy patient. For RT-PCR, RNAs were extracted from 11 patients with chronic sinusitis, 8 patients with allergic rhinitis, and 4 patients with hypertrophic rhinitis. RESULTS: Whereas IL-8 mRNA was expressed in the maxillary mucosa, IL-8 transcript was not detected in the inferior turbinate by Northern blot analysis. IL-8 transcripts were detected in 45% of chronic sinusitis RNAs (5/11) and in 50% of allergic rhinitis RNAs (5/10) by RT-PCR. CONCLUSION: These data suggest IL-8 may contribute to neutrophil involvement in chronic sinusitis.

Adolescent↗

MUC2 mucin gene expression in the nose and maxillary sinus.

PURPOSE: The MUC2 gene encodes the core protein of a mucin expressed in the intestine and lower airway. The purpose of this study is to examine if the MUC2 gene is expressed in the nose and maxillary sinus. MATERIALS AND METHODS: A Northern blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) were performed. For the Northern blot analysis, RNAs were extracted from maxillary mucosae and nasal polyps of patients with chronic sinusitis and from the inferior turbinates of a nasal allergy patient. For RT-PCR, RNAs were extracted from 10 patients with chronic sinusitis, 4 patients with allergic rhinitis, 2 patients with hypertrophic rhinitis, and 6 volunteers with normal nasal mucosa. RESULTS: Hybridization of the Northern blot with SMUC41 (a part of MUC2) cDNA probe showed clear bands in 2 of the 3 samples. In RT-PCR, the first round of amplification (35 cycles) failed to give any bands, but the additional 30 cycles with internal primers gave bands in 6 of 22 samples. CONCLUSIONS: These results indicate that MUC2 mucin gene is expressed in the nose and paranasal sinus. This two-round RT-PCR method will be useful for analysis of MUC2 mucin gene expression using relatively small amount of RNA.

Adolescent↗

Kinetics of lysosomal protease activity in human otitis media with effusion.

Hydrolytic activity of various lysosomal proteases--elastase, collagenase, and cathepsins B and H--were measured in 125 middle ear effusions from patients with chronic (serous and mucoid) and acute otitis media with effusion (OME). The levels of cathepsin B activity and alpha-2-macroglobulin during the course of clinical therapies (myringotomy and tympanostomy tubing) were analyzed in 10 chronic OME cases where follow-up evaluation was possible. It is found that the level of lysosomal protease activity (elastase, collagenase and cathepsin B) was higher in acute OME than that in chronic OME; the hydrolytic activity of cathepsin B in middle ear effusions could be used as an indicator to reflect the level of lysosomal proteases activity in the middle ear; in chronic OME, inflammatory reaction including lysosomal protease activity of the middle ear mucosa at the time of the first myringotomy appeared to be more active than that at the time of the final myringotomy, but less than that in acute OME; and the proteolytic damage of lysosomal thiol proteases to the middle ear mucosa, which may be related to the chronicity of OME, could be reduced by both therapeutic myringotomy and tympanostomy.

Cathepsin B↗

Recurrence of antigen-induced otitis media by thiol compound.

Reduced glutathione (GSH), a potential factor in the chronicity of human otitis media, was tested to determine its potency in the recurrence of antigen-induced otitis media in chinchillas sensitized with human serum albumin (HSA). GSH instillation into the healing middle ear bulla reproduced a level of otitis media similar to the original antigen-induced otitis media with cellular involvement occurring earlier, according to cytologic analyses. This study indicates that GSH is probably a factor in recurrent antigen-induced otitis media, controlling the balance between thiol proteases and thiol protease inhibitors during middle ear inflammation.

Animals↗

Antiinflammatory effects of a corticosteroid and protease inhibitor agents on antigen-induced otitis media in chinchillas.

Using an antigen-induced otitis media (OM) model in chinchillas sensitized with human serum albumin (HSA), we studied the antiinflammatory effect of a corticosteroid (triamcinolone) and a protease (kallikrein) inhibitor (aprotinin) by conducting both biochemical and cytologic analyses of middle ear fluid (MEF). The levels of HSA, alpha 1-antitrypsin, alpha 2-macroglobulin, and total protein concentration were measured in the MEF to evaluate the degree of OM. Both vascular leakage and leukocyte infiltration were significantly reduced by corticosteroid and inhibitor treatments. HSA levels in the MEF were markedly reduced after HSA challenge, and both treatments reduced the drop in HSA levels. In conclusion, the kallikrein-kinin system is related to the early stage of antigen-induced OM. Both corticosteroid and inhibitor treatments effectively reduce the degree of antigen-induced OM in chinchillas, suggesting that both may be useful local therapeutic agents in the treatment of human OM.

Animals↗

Rheological properties of middle ear effusions from children with otitis media with effusion.

Freshly harvested middle ear effusions (MEE) were collected from children with otitis media with effusion. Both elasticity (G') and viscosity (eta') of the MEE were determined by an oscillating sphere magnetic rheometer and compared with transportability of the MEE on mucus-depleted frog palates. A maximum value of transport was obtained at G' of about 20 dyne/cm2 (at 1 Hz), and below this value there was a significant positive correlation between the transport rate and log G'. Above 20 dyne/cm2, the negative correlation between the transport rate and log G' was significant. This shows there is a sharp increase in transport with increase in G' up to 20 dyne/cm2, and at the higher value of G' there is a slow decrease in transport with increasing G'. A similar significant correlation between the transport rate and log eta' was observed.

Adolescent↗

Significance of kallikrein-kinin system in otitis media with effusion.

Significance of the kallikrein-kinin system in the pathogenesis of otitis media with effusion (OME) was evaluated by prekallikrein level, kallikrein activity, and concentration of high molecular weight (HMW) kininogen in 45 middle ear effusions (MEEs, 38 serous and seven mucoid). All MEEs had varying prekallikrein levels (73.1 +/- 127.5 relative fluoro units [RFU]), and the mean value in serous effusions (82.2 RFU) was much higher than that in mucoid effusions (23.0 RFU). Hydrolytic activity of kallikrein in serous effusions was 18.0 +/- 27.9 RFU, and was significantly higher than that in mucoid effusions (8.0 +/- 4.2 RFU, p less than 0.05). Concentration of HMW kininogen in serous effusions was 51.2 +/- 72.77% of plasma value, but it could not be detected in any mucoid effusions. Analysis of protein composition by polyacrylamide gel electrophoresis indicates that plasma protein that has leaked into the middle ear is a major component of MEEs. The kallikrein-kinin system would be active in serous effusions, and liberated bradykinin enhances vascular permeability in the middle ear mucosa, leading to profuse plasma leakage, which characterizes the component of serous effusions. On the other hand, this system would almost be consumed in mucoid effusions.

Adult↗