Biomedical subjects

Y Majima

Publications and source records attributed to Y Majima.

216 records · Page 12Linked to original sources

PubMedDate not supplied

Current trends in cataract and refractive surgery in Japan: 1998 survey.

PURPOSE: A seventh annual survey was carried out by mail in February 1999 to investigate the current trends in cataract and refractive surgery in Japan. METHODS: Questionnaires were sent to 925 ophthalmologist members of the Japanese Society of Cataract and Refractive Surgery. Data received from 411 (44.4%) of the recipients were cross-analyzed and compared with those from the previous surveys. RESULTS: In cataract surgery, 93% of respondents preferred phacoemulsification, 58% employed the self-sealing wound closure technique, and 23% used topical anesthesia for phacoemulsification. CONCLUSIONS: There have been trends toward more surgical procedures performed by a surgeon, shorter period of hospitalization, and increased number of outpatient procedures. In refractive surgery, surgeons remained rather conservative; with 26% and 5% of surgeons doing astigmatic keratotomy and refractive keratotomy, respectively. Photorefractive keratectotomy, laser in situ keratomileusis, phakic intraocular lens, and intrastromal corneal ring were judged to be useful refractive surgical procedures by 58.2%, 69.5%, 25.4%, and 8. 8% of the respondents, respectively.

Adult↗

PubMedDate not supplied

Use of bifemelane hydrochloride in improving and maintaining the visual field of patients with glaucoma.

We investigated the change of visual fields in 40 patients with primary or secondary glaucoma. No limitations were placed on the type of angular glaucoma (ie, open or closed). The intraocular pressure of the patients had been controlled at < 20 mm Hg for 2 years before the study, and patients with normal-tension glaucoma also were included. We evaluated the effect of 48 months of treatment with bifemelane hydrochloride, 150 mg/d in three divided doses, on 20 patients with glaucoma. The control group included 20 glaucoma patients whose intraocular pressure had been controlled at < 20 mm Hg for 2 years before the study by the instillation or oral administration of an intraocular hypotensive agent. They had not received any oral agent, such as a cerebral circulation metabolism activator. Results showed that the visual field was improved in 14 (70%) of 20 patients who received bifemelane hydrochloride, whereas the visual field was improved in 4 (20%) of 20 patients in the control group. More patients in the bifemelane hydrochloride group had improved visual fields than in the control group; differences between groups were significant. In addition, an evaluation of the visual field with the use of the Kosaki and Inoue classification showed improvement in all patients in stages IIa to V. We conclude that this drug is useful for maintaining and improving the disturbed visual field of patients in whom the intraocular pressure can be maintained at < 20 mm Hg and in patients who can tolerate 150 mg/d in three separate doses.

Adult↗

PubMedDate not supplied

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↗

PubMedDate not supplied

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↗

PubMedDate not supplied

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↗

PubMedDate not supplied

Lysosomal thiol proteases in middle ear effusions.

Hydrolytic activity of lysosomal cathepsins B and H, and trypsin-like proteases in 115 middle ear effusions (MEEs, 40 serous and 75 mucoid) from chronic otitis media with effusion (OME) patients was measured and compared to that in plasma. The activity of both cathepsins in MEEs was significantly higher than that in plasma (p less than 0.01), and cathepsin B activity in mucoid MEEs was also significantly higher than that in serous MEEs (p less than 0.01). The activity of trypsin-like proteases was very weak in both MEEs and plasma. Profiles of various inhibitors indicated the qualitative difference of proteolytic enzymes between MEEs and plasma. Mucoid MEEs had significantly higher activity of thiol proteases than serous ones (p less than 0.01). Cathepsin B-like lysosomal thiol proteases, derived mainly from macrophages, could become a major proteolytic factor to perpetuate and amplify the inflammatory reaction of chronic OME.

Adult↗

PubMedDate not supplied

Hearing impairment in relation to viscoelasticity of middle ear effusions in children.

Both dynamic viscosity (eta') and elasticity (G') of middle ear effusion were measured with an oscillating sphere magnetic rheometer and compared with the degree of conductive hearing loss in 65 ears of 40 children. There was a significant correlation between eta' and the magnitude of the air-bone gap at 500 and 1,000 Hz, but there was no significant correlation between eta' and the magnitude of the air-bone gap at 2,000 or 4,000 Hz. No significant correlation was noted between G' and the magnitude of the air-bone gap at 500, 1,000, 2,000, or 4,000 Hz. These results indicate that the eta' of middle ear effusion has an effect on the amount of hearing impairment at frequencies below 1,000 Hz.

Child↗

PubMedDate not supplied

Ultrastructure of mucous blanket in otitis media with effusion.

We used transmission electron microscopy to study the mucous blanket of the promontory from children with otitis media with effusion. The vast majority of the epithelial cells were secretory, and the rest were ciliated. The mucous blanket consisted of the electron-lucent periciliary fluid and the mucous layer. In the mucous layer, two layers were identified: an inner layer with migrating cells, and an outer layer with specks. Moreover, there was a lucent zone over the nonciliated surface that was as high as the microvilli. The thickness of the periciliary layer was predominantly as great as that of the ciliary tips, which just make contact with the mucous layer; however, the mucous layer occasionally penetrated into the periciliary space. These findings indicated that there is a mucociliary dysfunction in the middle ear caused by a decrease in the number of ciliated cells, and an abnormal interaction between cilia and mucus that would interfere with ciliary movement. Thus, such a system would fail to transport the mucous blanket.

Biopsy↗

PubMedDate not supplied

Monoclonal antibody-detectable carbohydrate epitopes of human nasal secretions are differentially expressed in tissue and diseases.

To study the differential carbohydrate expression of airway secretions, we have produced a series of monoclonal antibodies that recognize human nasal secretory cell products. Mice were immunized with purified nasal secretion from patients with chronic sinusitis (CS) and hybridomas were selected by ELISA and immunohistochemical staining of the maxillary sinus mucosa from patients with CS. Eighteen antibodies were obtained. Antibody HCS 18 reacted with epithelial goblet cells, antibody HCS 4, 5, 6, and 16 stained submucosal gland cells, and antibody HCS 13 and 15 reacted with epithelial goblet cells, submucosal gland cells, and endothelial cells of vessels. The other eleven antibodies recognized epithelial goblet cells and submucosal gland cells. Cross-reactivity of these antibodies with secretory cells in other organs and in other species was determined and the different staining pattern was observed between upper and lower airway tissue, suggesting that secretory products from upper and lower airways may be different. Reactivity of the antibodies with nasal secretory cells was also examined in patients with perennial allergic rhinitis (AR) and normal subjects. Antibody HCS 18 weakly reacted with nasal glands in the tissue from CS and AR patients, but minimally reacted with gland cells in normal tissue. Antibody HCS 1 and 7 partially lost their reactivity with nasal epithelium of inferior turbinate from normal subjects and AR patients. These antibodies may be useful to study nasal secretions.

Adolescent↗

PubMedDate not supplied

Nasal mucociliary clearance under various conditions.

We applied the tagged-particle method or the saccharin method or both to the nasal mucociliary clearance. There was no effect of ageing on the transport time of saccharin in control subjects of ages under 60, and 70% of control subjects of ages more than 60 had the same transport time as that obtained in younger control subjects. The significant inverse correlation between the mucociliary transport rates with the particle method and the transport time with the saccharin method were established in control subjects, but not, however, in patients with chronic sinusitis. The mucociliary transport rates were measured under non-physiologic conditions of the nose: laryngectomy, chronic sinusitis, Sjögren's syndrome, and Kartagener's syndrome.

Adolescent↗

PubMedDate not supplied

Effect of SO2 on nasal secretory cells.

Quantitative histochemical analysis of the secretory cells producing the different types of glycoproteins were examined in the chicken nasal cavity with and without moderate levels of SO2 exposure for 14 days. On the nasal maxillary concha of chickens, the number of acinar gland cells containing glycoproteins was significantly reduced on the 1st, 7th and 14th days of exposure to 11.8 ppm of SO2, but not on the 5th day of exposure. There was no histochemical modification in the intracellular glycoproteins of the acinar cells. The number of goblet cells in the same region increased greatly and showed a change of intracellular glycoproteins from neutral to acid between the 5th and 7th day of exposure.

Animals↗

PubMedDate not supplied

Lysosomal thiol proteases (cathepsin B-like proteases) in serous middle ear effusions from adult patients.

Hydrolytic activity of cathepsins B, H and trypsin-like proteases was measured in 38 serous middle ear effusion (MEE) samples. The concentrations of (alpha 1-AT) and alpha 2-macroglobulin (alpha 2-M) were also quantitated. The mean value of cathepsin B activity was 25.0 +/- 20.7 RFU and that of cathepsin H was 14.3 +/- 3.0--both significantly higher than those in plasma (1.8 +/- 0.4 RFU, 1.2 +/- 0.3 RFU, p less than 0.005). Very low trypsin-like protease activity could be observed. The mean concentrations of alpha 1-AT and alpha 2-M were 368 +/- 94.8 mg/dl and 57.5 +/- 57.3 mg/dl. The bulk of alpha 1-AT in MEEs was occupied by free alpha 1-AT, which can saturate exogenous trypsin. Due to the very low molar concentration of alpha 2-M in MEEs, thiol proteases (mainly cathepsin B) could be a possible major factor inflicting proteolytic injury on the middle ear mucosa and reflecting the severity of the inflammatory process.

Adult↗

PubMedDate not supplied

Cathepsin B-like thiol proteases and collagenolytic proteases in middle ear effusion from acute and chronic otitis media with effusion.

Hydrolytic activity of cathepsin B-like thiol proteases and collagenolytic proteases was measured in middle ear effusions (MEE) from pediatric patients with acute and chronic otitis media with effusion (OME). Both activities were significantly higher in MEEs from acute OME than those from chronic OME (p less than 0.01). The ratio of hydrolytic activity in the extracellular portion to the total activity in MEEs from chronic OME was also analysed in both proteases. The ratio ranged from 20 to 100% in individual cases, indicating that the degree of the release of lysosomal thiol proteases including collagenolytic proteases from leukocytes is variable in MEEs with chronic OME. The kinetics of lysosomal thiol proteases including collagenolytic proteases in acute OME seems to be much more active than that in chronic OME, and the presence of these thiol proteases appears to be an important factor leading to chronic OME.

Acute Disease↗

PubMedDate not supplied

Nasal mucociliary clearance in Sjögren's syndrome. Dissociation in flow between sol and gel layers.

Nasal mucociliary clearance was measured with two methods in 8 patients with Sjögren's syndrome and in 6 normal subjects. The movement of two different tracers placed 1.5 cm posterior to the inferior turbinate tip was measured respectively. The transport rate of a 500 microns anion resin particle tagged with 99mTc was measured. The clearance of 10 microliters saline labelled with 99mTc was monitored and the clearance rate was calculated. Whereas the measurement with the particle method revealed the lowered transport rate in Sjögren's syndrome, measurement with the saline method did not reveal any difference in clearance rate between the two groups. Since the former method measures the transport of particle in the gel phase (the outer mucous layer) and the latter measures the clearance of both gel and sol (periciliary fluid) layers, it is postulated that there is a dissociation of flow between sol and gel layers in Sjögren's syndrome.

Anion Exchange Resins↗

PubMedDate not supplied

Effect of atropine on nasal mucociliary clearance.

To investigate the effect of atropine on mucociliary function, nasal mucociliary clearance was measured with two methods in eight healthy men before and after subcutaneous injection of atropine sulphate. The movement of two different tracers placed 1.5 cm posterior to the inferior turbinate tip was measured. The transport rate of a resin particle tagged with 99mTc was measured. The clearance of 10 microliters saline labelled with 99mTc was monitored and the clearance rate calculated. Whereas atropine lowered the resin particle transport rate, the saline method did not reveal any difference in clearance rate after injection of atropine. Since the former method measures the transport of particles in the gel phase (the outer mucous layer) and the latter measures the clearance of both gel and sol (periciliary fluid) layers, it is postulated that the slowing of mucociliary transport by atropine is due to alterations in the gel layer.

Adult↗

PubMedDate not supplied

Bright loop appearance; a characteristic ultrasonography sign of early hepatocellular carcinoma.

Ultrasonography (US) and computed tomography (CT) are the most effective screening methodologies for hepatocellular carcinoma (HCC). In our US screening, 20% of small HCC nodules less than 20 mm in diameter were detected as hyperechoic tumors. Among these hyperechoic HCC nodules, we have often observed (BL) which is defined as hypoechoic nodules in the hyperechoic tumor. In this study, we report that the BL is a sign of dedifferentiation of early stage of HCC with fatty change by US. From 1994 to 1998, we performed tumor targeting needle biopsy in 938 hepatic nodular lesions. Among them, 284 nodules <20 mm in diameter, histologically diagnosed as HCC, were studied. BL is defined as a hyperechoic tumor containing a hypoechoic nodule >4 mm in diameter by US. Among 284 nodules, well, moderately and poorly differentiated HCC were 183 (64.4%), 100 (35.2%) and 1 (0.4%), respectively. On US, hypoechoic, isoechoic, and hyperechoic nodules were 188 (66.2%), 32 (11.3%) and 64 (22.5%), respectively. Forty-seven nodules of 64 hyperechoic HCC nodules <20 mm in diameter, 47 nodules (73.4%) showed fatty changes. Of 64 hyperechoic HCC nodules, we recognized 22 nodules (34.4%) as BL. The proportion of BL type hyperechoic nodules increased with the tumor size. Two hyperechoic nodules followed by US changed to BL with tumor enlargement. Histologic examination of a resected HCC with BL showed that hyperechoic HCC nodule represented well-differentiated HCC with fatty change and inner hypoechoic lesion represented moderately differentiated HCC without fatty change. In US screening for HCC, BL was often observed in HCC nodules from 11 to 20 mm in diameter. Histologic examination revealed that BL of HCC on US was associated with tumor progression and indicated dedifferentiation showing moderately differentiated HCC in well-differentiated HCC with fatty change.

Adult↗

PubMedDate not supplied

Brachytherapy of a choroidal melanoma using radioactive gold grains: a long-term follow-up study.

PURPOSE: We used radioactive gold grains to treat a patient with choroidal malignant melanoma. Radioactive sources were placed into surgically constructed scleral pockets. The patient was followed up for six years after therapy to assess changes in the tumor, recurrence, and side effects. METHODS AND MATERIALS: A male patient presented with malignant melanoma arising from the choroidal membrane of the posterior pole of the left eyeball. We placed radioactive gold grains into surgically constructed scleral pockets adjacent to the tumor, arranged in a plane based on the Manchester's method. The patient was followed up for six years after treatment. RESULTS: The radiation dose was 120 Gy at the apex of the tumor, which slowly became smaller and completely disappeared at one year and 10 months after treatment. Tumor recurrence was not observed. Radiation dose at the ipsilateral lens was 280 cGy. Side effects associated with therapy were a decrease in visual acuity secondary to retinal degeneration and atrophy, but his vision was correctable with suitable glasses. In addition, the visual field of the left eye was also restricted. Mild cataracts also developed in the ipsilateral eye after treatment. CONCLUSION: Although this therapeutic method is technically difficult compared with other methods, it permits the tumor to be treated without loss of the eye. This may significantly improve the patient's quality of life.

Adult↗

PubMedDate not supplied

Effect of lipopolysaccharide of Haemophilus influenzae on ciliary activity of the human nasal mucosa and bullfrog palate clearance.

The influence of lipopolysaccharide (LPS) of Haemophilus influenzae on the ciliary activity of human nasal mucosa was first studied using both a photo-oscillographic apparatus and by bullfrog palate clearance. Neither modification of ciliary activity nor change in bullfrog palate clearance was observed in the early phase after the administration of LPS.

Animals↗