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Biomedical subjects

Y Esaki

Publications and source records attributed to Y Esaki.

102 records · Page 6Linked to original sources

Immunohistochemical study on the liver in autopsy cases with disseminated intravascular coagulation (DIC) with reference to clinicopathological analysis.

Immunohistochemical and clinicopathological studies were performed in 27 autopsy cases with indisputable DIC, which had been selected from 1,800 autopsy cases of elderly people based on the following two criteria; 1. presence of fibrin thrombi in glomeruli, and 2. presence of fresh patchy necrotic foci in myocardium and/or fibrin thrombi in splenic sinuses. A high incidence of liver lesions (22/27) was revealed in autopsy cases with indisputable DIC. The liver lesions could be classified into four groups. Group-I (Central degeneration) was characterized by massive precipitation of fibrin irregularly around the central vein, causing parenchymal damage. Group-II (Central necrosis), showed coagulation necrosis in the central zone due to circulatory disturbance caused by either shock as a cause of DIC or abrupt cessation of blood flow into the lobules following fibrin thrombus formation in vessels of Glisson's sheath. Both group-I and -II showed a short clinical duration of DIC. Group-III (Sinusoidal thrombosis), showed the presence of fibrin thrombi in sinusoids with mild parenchymal damage and long clinical duration of DIC. Group-IV (No thrombosis), showed neither parenchymal damage nor fibrin thrombi in sinusoids, but a long clinical duration of DIC.

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Amyloid deposits in the aged tongue: a postmortem study of 107 individuals over 60 years of age.

The incidence and distribution of amyloid deposits in aged tongues obtained from 107 necropsies over 60 years of age were examined. Thirty-nine tongues were affected with amyloid deposits and the overall incidence was 36.4%. The incidence increased with each advancing decade, and the group over 90 years old showed the highest incidence of 59.6%. Although the amount of amyloid deposits differed in each case, severely affected cases were most frequently found in the advanced decades. Amyloid deposits were almost always confined to blood vessels, especially arterioles and arteries. They occasionally occupied the entire wall and occluded the lumen. Blood vessels affected with amyloid were usually located in the muscle layers of the tongue. Vessels in the subepithelial layer and lingual glands were, however, sometimes affected. Amyloid deposits were resistant to Congo red staining with the potassium permangante method, and stained positively with DMAB. The present study suggested that the tongue is an important organ as to the appearance of amyloid deposits in elderly persons.

Age Factors↗

Mucosal pathology of an experimental otitis media with effusion after X-ray irradiation.

Ten guinea pigs were irradiated with 30 Gy of x-radiation. Five were killed on the eighth day after irradiation, and the remainder were killed at the sixteenth day after irradiation. At the time of death, examination was made of the ciliary activity and the fine structure of the middle ear mucosa. Serous effusion was found in each tympanic cavity of all animals. It was shown also that the guinea pig, when irradiated with 30 Gy of x-radiation, exhibits pathologic abnormalities similar to those in humans with otitis media with effusion: degeneration of cilia or ciliated cells and changes in the vascular system (capillary injury and increased capillary permeability). Functional examinations showed that x-ray irradiation has delayed effects on ciliary activity, and the effects are much greater at the sixteenth day than at the eighth day. We speculate that the accumulation of effusion can be, at least partially, a consequence of ciliary dysfunction. The induction of sterile effusion by the use of x-ray irradiation provides a unique animal model for chronic otitis media with effusion of the serous type.

Animals↗

Experimental otitis media with effusion induced by lipopolysaccharide from Klebsiella pneumoniae: mucociliary pathology of the middle ear.

We inoculated 100 micrograms/ml of lipopolysaccharide (LPS) from Klebsiella pneumoniae into the tympanic cavity of guinea pigs and examined the mucociliary pathology in the middle ear. Serous effusion was observed in the tympanic cavity of every animal on the first, third, and seventh day following the procedure, but the volume of the effusion had decreased to 0.2 ml on day 7. By that time, the ciliary activity in the opening to the eustachian tube within the middle ear had recovered to some extent, but in the middle ear distal to the opening no recovery was apparent. Our results show that cilia close to the eustachian tube play a more significant role in middle ear clearance than those in the middle ear distal to the tube. Compared with our previous study using 10 micron/ml of LPS, this study also demonstrates that inoculations with a higher concentration of LPS induces longer-term middle ear effusions.

Animals↗

Ciliary activity on adenoids of patients with otitis media with effusion.

Ciliary activity of the adenoidal surface in patients with otitis media with effusion (OME) was evaluated by a photoelectric method. Three groups of patients were compared: a non-OME group whose members had experienced no episode of OME; a middle ear effusion (MEE)-negative OME group whose members had an episode of recurrent OME but no MEE during the month preceding the operation; and an MEE-positive OME group whose members were experiencing an episode of recurrent OME with MEEs when tissue was taken for examination. To serve as a comparison, the ciliary activity in the central pharynx of normal guinea pigs was evaluated using the same technique. The ciliary activity in all patients was significantly lower than that in normal guinea pigs. No significant difference in ciliary activity was apparent between the non-OME group and the MEE-negative OME group. However, both were significantly higher than the ciliary activity of the MEE-positive OME patients. The following findings are drawn from our data: ciliary activity on the surface of hypertrophic adenoids is depressed, and patients with OME have reduced ciliary activity compared with those who have no otitis media or those who have otitis media without effusion.

Adenoids↗

Acute effects of irradiation on middle ear mucosa.

Single field, fixed irradiation of bilateral tympanic cavities using 200-kV x-rays was administered to five guinea pigs. The irradiation dose was 30 Gy. They were killed immediately after irradiation, and bilateral middle ear mucosa was examined for ciliary activity and epithelial structure. Significant deterioration of the ciliary activity in the middle ear mucosa was observed, proximal as well as distal to the eustachian tube. Electron microscopy showed various changes in the irradiated middle ear mucosa. The most conspicuous findings were hyperreactivity in secretion, vacuolation of ciliated cells, and stomal edema.

Animals↗

Effects of bacterial endotoxin on ciliary activity in the tubotympanum.

The discovery of endotoxin in effusion of otitis media with effusion (OME) has suggested the possibility that bacterial endotoxin may be involved in the pathogenesis and development of OME. In this study, we investigated the direct effects of lipopolysaccharide (LPS), possessing the major part of endotoxin activity, on the ciliary activity in the tubotympanum. The study shows that LPS deteriorates ciliary activity in a dose-response fashion and that even low levels can, with extended exposure, cause dysfunction of cilia. It can be postulated that endotoxin in middle ear effusions aggravates the condition of mucociliary dysfunction thus leading to chronic OME.

Animals↗

Functional disorder of eustachian tube in experimental otitis media with effusion following inoculation of bacterial endotoxin.

A 10-micrograms/mL solution of lipopolysaccharide derived from Klebsiella pneumoniae was inoculated into the middle ears of guinea pigs. The animals were killed painlessly on the first, third, or seventh day after inoculation, and the mucosal samples from the bony portion of the eustachian tube were examined for ciliary activity and epithelial morphology. On the first and third days, when middle ear effusions were present, deterioration of ciliary activity and morphologic changes in the mucociliary system were observed. On the seventh day, when middle ear effusions were absent, the ciliary activity had recovered to normal. Our data show that endotoxin extracted from K pneumoniae can produce otitis media with effusion and that dysfunction of cilia caused by endotoxin is a factor responsible for the manifestation of otitis media.

Animals↗

Effects of bacterial endotoxin on the ciliary activity in the in vitro middle ear mucosa.

In the present study, we have examined the hitherto unknown effects of long-term exposure to lipopolysaccharide (LPS), possessing the major parts of biological activity of endotoxin, on ciliary activity in the middle ear. Our results show that LPS can affect the ciliary activity in a dose-response fashion: 1) LPS does not impair the ciliary activity up to 168 h if the concentration is 1 ng/ml or less; 2) 10 ng/ml of LPS does not impair ciliary activity in the middle ear close to the tympanic orifice up to 168 h, but can cause reduced activity distal to the orifice after extended exposure (more than 96 h); 3) 100 ng/ml or more of LPS can cause dysfunction of cilia in the tympanic cavity, and in particular 1 microgram/ml or more of LPS can quickly disable the ciliary activity in the middle ear distal to the orifice.

Animals↗

[A clinicopathological study of ruptured infectious aneurysms].

We investigated 952 consecutive autopsy cases between January 1990 and May 1994 to identify ruptured infectious aneurysms (IAs) of the aorta or iliac artery. Twenty patients (2.1%) died of artrial rupture, including 9 men and 11 women. The cause of rupture was IA in four cases (0.42%), atherosclerotic aneurysm (AA) in nine (0.95%), dissection (D) in six (0.63%), and aortoenteric fistula due to irradiation in one (0.11%). Infection of pre-existing aneurysms was considered to be AA rather than IA and the patient with aorto-enteric fistula was excluded from the study. Patients with IA were significantly older than other patients (IA: 85.8 +/- 4.3, AA: 80.2 +/- 4.1, and D: 77.7 +/- 5.0 years old), and were less frequently accompanied by leukocytosis than patients with AA, although this difference was not significant (11,100 vs 13,000). The four patients with IA consisted of one man and three women, all of whom died suddenly. Two patients had perforation in the atherosclerotic descending aorta and the other two had perforation in the atherosclerotic common iliac artery. Histological examinations revealed marked neutrophilic infiltration in all four cases, and bacterial colonies in three cases. In conclusion, IAs were not rare. Since they often cause sudden death, special attention should be given to elderly patients who develop infection.

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Preclinical primary central nervous system lymphoma.

We report an autopsy case of preclinical primary central nervous system (CNS) lymphoma. The case was an 89-year-old female who died of rupture of a thoracic aortic aneurysm. No neurological abnormalities were found throughout our clinical observation. Serum anti-human T-cell leukemia virus type 1 and anti-human immunodeficiency virus were negative. Grossly, the brain was normal except for a small solid tumor, 6 by 6 by 2.5 mm, in the lateral ventricular wall at the left hippocampal fimbria, and multiple smaller disseminated nodules. Histological examination revealed multiple microscopic disseminated foci throughout the brain, including the cerebral subcortical white matter, basal nucleus, thalamus, brainstem and cerebellum. Histological classification is of lymphoblastic type non-Hodgkin's lymphoma of high-grade malignancy. Lymphoma cells are positive for leukocyte common antigen and L-26, indicating a B cell phenotype. In situ hybridization with Epstein-Barr viral probes is negative. It is concluded that this case may represent a relatively early preclinical stage of multifocal type of primary CNS lymphoma.

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