Biomedical subjects

Y Hamaguchi

Publications and source records attributed to Y Hamaguchi.

At least 91 records · Page 5Linked to original sources

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↗

PubMed1991

Quantitative histochemical study of secretory cells after short term tubal obstruction in the cat.

Quantitative histochemistry of goblet cells producing different types of glycoproteins was examined in cat middle ears with and without Euatachian tube obstruction (ETO). The goblet cell population significantly increased at 1 week after ETO and showed a tendency to decrease down to the normal level at 4 weeks after ETO. In the normal ears, approximately 85% of glycoprotein in the secretory cells were sulphated and 15% were neutral. ETO significantly increased goblet cell population containing sulphated glycoprotein at the expense of neutral glycoprotein. The results indicate that goblet cells can easily and within a short period be modified both in number and in intracellular glycoproteins by a tubal obstruction.

Animals↗

PubMed1991

ELISA for determination of immunoreactive free elastase and elastase in complex with alpha 1-antitrypsin in nasal secretions with sinusitis.

Sensitive double antibody sandwich ELISA methods was developed in order to quantify immunoreactive neutrophil elastase (NE) levels in nasal secretions with chronic sinusitis (CS). Microwell plate as a solid phase was coated with anti-NE antibody. Two different horseradish peroxidase (HRP) labelled antibodies used as the second antibody were anti-NE-HRP for measuring total (free + complexed) NE level and anti-alpha 1-antitrypsin (AT)-HRP for complexed NE level. Mean value of total NE was 31.0 +/- 20.7 micrograms/ml in nasal secretions from adult patients with CS, and the percentage of complexed NE in total NE was 33.7 +/- 21.4%. This sandwich ELISA is a useful method for measuring both total and complexed NE levels in nasal secretions.

Chronic Disease↗

PubMed1991

Neutrophil elastase and its complex with alpha 1-antitrypsin in soluble and insoluble fractions of nasal secretions of chronic sinusitis.

Immunoreactive neutrophil elastase (NE) and its complex with alpha 1-antitrypsin (AT) was measured by double antibody enzyme linked immunosorbent assay (ELISA) in nasal secretions of chronic sinusitis (CS). Nasal secretions were separated into two fractions: PBS-soluble and insoluble fractions. Elastolytic activity was also examined. Mean value of total NE level was 31.0 micrograms/ml in the soluble fraction, which was significantly lower than that in the insoluble fraction (71.9 micrograms/ml, p less than 0.01). On the other hand, the percentage of complexed NE in total NE in the soluble fraction (33.7%) was significantly higher than that in the insoluble fraction (12.1%, p less than 0.01). Elastolytic activity in the soluble fraction (23.4 RFU) was significantly lower than that in the insoluble fraction (170.5 RFU, p less than 0.01). NE with elastolytic activity exists in nasal secretions of CS, and active-free NE in the insoluble fraction could be a major source of enhancement and continuation of mucosal inflammation.

Amino Acid Sequence↗

PubMed1991

[Effect of recognition of head and neck malignancies on patients' psychosomatic condition and personality].

In order to elucidate the effect of recognition of head and neck malignancies on patients' psychosomatic condition and personality, we applied the Cornell Medical Index Health Questionnaire (CMI) and the Maudsley Personality Inventory (MPI) and collected medical and psychological data from 35 male (42-78 years of age; average 62.5) and 15 female (20-76 years of age; average 54.7) patients with malignant head and neck tumors (10 nose and paranasal, 8 oral, 8 pharyngeal, 14 laryngeal, 6 thyroid gland and 4 others). The two tests were done twice for each patients; at first immediately before hospitalization for treatment of the tumors at Mie University Hospital and secondly just before discharge from the hospital. The period of hospitalization ranged 1 to 13 months, average 3.3 months. At the end of hospitalization doctors and nurses who had mainly taken care of the patients estimated the patients' recognition of their malignancy by analyzing behavior and information mainly from their family and classified patients into three groups; Group R (Patients who recognized that they were patients with head and neck malignancies) comprised 22 patients, Group N (who did not recognize the condition) comprised 15 and Group U (who could not be classified into Groups R or N) comprised 13. Comparison among the three groups revealed the followings. 1) Patients in Group R were relatively young (average 56.3 years) and extrovert (estimated by MPI) and their somatic and psychological complaints registered on the CMI were less than those in other 2 groups. Psychosomatic condition after recognition that they had been patients with malignant tumors was better than before.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

[A case of lobar cerebral hemorrhage with low concentration of CSF cystatin C].

A 49-year-old male was admitted to our hospital because of severe headache and dizziness which had occurred suddenly one day before admission. There was no past history contributory to cerebral hemorrhage but was family history of cerebrovascular accidents in his father and brother. Neurological examination revealed left homonymous hemianopsia, mild left hemiparesis, and left side hemi-neglect in simultaneous stimuli on bilateral extremities. Laboratory data including peripheral blood cells, coagulation tests, and serum chemistry were unremarkable. Brain CT and MRI demonstrated large lobar hematoma in the right parieto-occipito-temporal region. Cystatin C level in the CSF samples taken on the 39th and 59 th days (38 and 27 ng/ml respectively) were low, compared with the normal value (greater than 100 ng/ml). These findings suggest that the lobar cerebral hemorrhage of the present case might have been caused by cerebral amyloid angiopathy with cystatin C deposits.

Amyloidosis↗

PubMed1990

Endotoxin and lysosomal protease activity in acute and chronic otitis media with effusion.

Endotoxin levels and lysosomal protease (collagenase, cathepsin B, and lysozyme) activity were measured in 104 middle ear effusions (MEEs) from patients with otitis media with effusion (OME). The MEE samples were classified into four groups: pediatric serous, mucoid, and acute, and adult serous. Endotoxin levels and lysosomal protease activity in MEEs were significantly different in the following order: adult less than serous less than mucoid less than acute groups, indicating that both endotoxin and lysosomal proteases are more closely related to the pathogenesis of pediatric chronic OME than to adult OME. In pediatric serous and mucoid effusions, endotoxin level had a significant correlation with activity of the lysosomal proteases. In conclusion, endotoxin enhances leukocyte infiltration into the middle ear, and lysosomal proteases released from leukocytes damage the middle ear mucosa and thereby prolong mucosal inflammation, which may be responsible for delayed recovery from acute OME.

Acute Disease↗

PubMed1990

Simultaneous investigation of intracellular Ca2+ increase and morphological events upon fertilization in the sand dollar egg.

An increase in intracellular Ca2+ concentration ([Ca2+]) and morphological were simultaneously observed by epifluorescence and differential interference contrast (DIC) microscopy during fertilization of the sand dollar, Clypeaster japonicus. [Ca2+], which was detected by a Ca2+ indicator, Fluo-3, initially increased just beneath the sperm-attached site on the egg surface 8.6 sec after attachment. The increase spread into the egg as a concentric sphere to the egg center and, thereafter, propagated in the egg cytoplasm as a planar wave rather than a spherical wave. It reached the site opposite the initiation site across the egg 24.2 sec after initiation. The fertilization envelope (FE) began to elevate 10.3 sec after the initiation of the increase in [Ca2+] and 21.2 sec after sperm attachment.

Aniline Compounds↗

PubMed1990

Quantitative analysis of the process and propagation of cortical granule breakdown in sea urchin eggs.

Cortical granule breakdown in sea urchin eggs has been investigated with a video microscope system using Nomarski differential interference contrast optics, when induced by fertilization, microinjecting inositol 1,4,5-trisphosphate (IP3) or Ca-EGTA buffer solution into the egg, or perfusing a medium containing 1 mM Ca2+ to isolated cortices. The cortical granule increased up to 1.2 times in diameter and broke down within 40 msec. These values were almost constant among the three methods used to induce cortical granule breakdown. Upon fertilization, the cortical granule breakdown propagated over the egg surface at a speed of 3.3 microns/sec in Clypeaster japonicus eggs, which indicates that cortical granule breakdown propagated through the 3.3-microns-wide egg surface within 1 sec. In such a small area of the egg surface, however, it took much more than 1 sec for all cortical granules to break down because the maximal rate of breakdown was 7.6%/sec; that is, it took 9 sec and 18 sec for 50% and 90% respectively, of cortical granules to break down. Moreover, the rate did not simply decrease with time, and a shoulder was found during the reducing phase, which suggests that cortical granules are divided into fast and slow breakdown groups according to the responsiveness to the breakdown stimulus. The cortical granule breakdown induced by microinjecting the Ca-EGTA buffer and IP3 solutions propagated at 68 microns/sec and 35 microns/sec, respectively. The stimulus for cortical granule breakdown is discussed concerning the transient intracellular Ca2+ increase.

Animals↗

PubMed1990

Microinjection of the monoclonal anti-tubulin antibody YL1/2 inhibits cleavage of sand dollar eggs.

Two monoclonal antibodies against alpha-tubulin (YL1/2 and D2D6) were microinjected into the egg of the sand dollar Clypeaster japonicus, and their effects on cleavage of the egg were investigated. They had already been shown by immunoblotting to react specifically with egg tubulin and by immunofluorescence to stain the mitotic apparatus [OKA et al., (1990). Cell Motil. Cytoskel. 16:239-250]. Injection of YL1/2 prevented chromosome movement and cleavage, although the cleavage furrow developed in some cases. In all eggs injected at prometaphase, metaphase, or anaphase, the birefringence of the mitotic apparatus disappeared immediately after injection. Injection of D2D6 had no significant effect on mitosis or cleavage of whole eggs injected after nuclear disappearance, although it prevented the disappearance of the nuclear envelope in 54% of the eggs injected before the disappearance. FITC-conjugated D2D6 did not accumulate in the spindle when injected into the dividing sand dollar egg. These results indicate that YL1/2 disassembled microtubules, whereas D2D6 did not bind to microtubules in the living cell.

Animals↗

PubMed1990

[An autopsy case of Alzheimer's disease associated with Parkinson's disease, compared to 2 autopsy cases of diffuse Lewy body disease].

A 68 year old male, diagnosed as Alzheimer's disease clinically, pathologically showed both findings of Alzheimer's disease and Parkinson's disease. The brain weight was 940 g. Macroscopically, severe cortical brain atrophy and depigmentation of the substantia nigra was noted. Microscopic examination showed marked appearance of senile plaque and a large number of neurofibrillary tangle with sever neuronal loss of the cerebral cortex. Additionally, the loss of neuron with many Lewy bodies was found in the substantia nigra. Lewy bodies were also found in the locus ceruleus and the dorsal vagal nucleus, but few in the cerebral cortical neurons. We compared this case neuropathologically with two autopsy cases of diffuse Lewy body disease (DLBD). There was no distinction concerning the lesions of the brain stem between this case and the cases of DLBD. In all three cases, the nucleus of basalis of Meynert showed marked neuronal loss. However, the brain was lighter than those of the cases of DLBD. Senile changes such as senile plaque and neurofibrillary tangles were more marked in this cases than in the cases of DLBD. Furthermore a large number of cortical Lewy bodies were found in the cases of DLBD, but few in this case. The distribution and number of Lewy bodies did not correspond with those of senile changes in the cases of DLBD. Also the cerebral cortical structure was better preserved in the cases of DLBD than in this case. In conclusion, from the clinicopathological findings, we considered that this case is Alzheimer's disease associated with Parkinson's disease. According to Kosaka's study, this case seemed to correspond with a transitional type of the Lewy body disease.

Aged↗

PubMed1989

Purification and characterization of a protein that binds to the recombination signal sequence of the immunoglobulin J kappa segment.

A protein that binds to the recombination signal sequence (RS) of the immunoglobulin J kappa segment was purified almost to homogeneity from the nuclear extract of a murine pre-B cell line 38B9. A similar binding protein was found in lymphoid cell lines but not in non-lymphoid cell lines. The binding activity was associated with a polypeptide with a molecular weight of 60,000. DNase I footprinting analysis demonstrated that this binding protein interacted with the heptamer and several 3' bases close to the heptamer. The Kd value of the J kappa RS binding protein to the J kappa RS was 1 nM. One base substitution in the heptamer of the J kappa RS greatly reduced the affinity of the J kappa RS binding protein. The high specificity of the binding site of the J kappa RS binding protein suggests that this protein may be involved in V-J recombination.

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

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

A comparative study of the distribution of fluorescently labeled calmodulin and tubulin in the meiotic apparatus of the mouse oocyte.

The localizations of tubulin and calmodulin were investigated in the mouse oocyte during the second meiosis by fluorescently labeling and microinjecting these proteins prepared from porcine brain tissue. When injected, both tubulin and calmodulin were quickly incorporated into the preformed meiotic apparatus of the oocyte at metaphase. The localization of labeled tubulin was coincident with that of birefringence. However, the localization of labeled calmodulin was somewhat different: the fluorescence of calmodulin was intense in the polar regions of the spindle. After the chromosomes began to move, followed by parthenogenetic activation upon microinjection of a calcium buffer, these two fluorescent proteins, localized in the meiotic apparatus, moved to the interzonal region of the spindle during anaphase. At late anaphase and throughout telophase, calmodulin was excluded from the mid-bodylike structures in the interzonal region, whereas tubulin did accumulate in these structures.

Animals↗

PubMed1989

Review of round window membrane permeability.

The round window membrane (RWM) is permeable to certain biological substances. Those substances that can pass through the RWM have the potential to cause inner ear damage, leading to functional disturbances. The RWM is permeable to water, and the existence of osmotically active substances in the middle ear cavity can induce an alteration of inner ear fluid osmolality, leading to membrane displacement. However, several limiting factors exist that prevent free passage of substances from the middle ear to the inner ear. These include the morphological barrier of the three-layered RWM, the molecular weight of the substances, and the nature and concentration of substances in the middle ear cavity. The degree and duration of the inflammation in the middle ear cavity, as well as the morphological integrity of the RWM, also play an important role in controlling the passage of noxious substances into the inner ear. Further characterization of the factors involved in RWM permeability, and clarification of the mechanisms of the inner ear damages caused by substances passing into the inner ear through the RWM, are necessary for an understanding of the inner ear dysfunction caused by middle ear inflammation.

Animals↗

PubMed1989

Sensorineural hearing loss in antigen-induced otitis media.

Chinchillas were sensitized with human serum albumin (HSA). When circulating antibody-titers were sufficiently elevated as to induce local inflammation, 1 ml of HSA (50, 5, 0.5 mg/ml) was instilled into the left middle ear cavity from the superior bulla. HSA containing a steroid agent was instilled into the right ear. Non-sensitized animals were used as control. In the sensitized animals, a significant hearing loss occurred at higher frequencies. The loss was dose-related. Less severe hearing loss was found following steroid treatment. We conclude that sensorineural hearing loss can occur in antigen-induced otitis media.

Animals↗