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H Okuno

Publications and source records attributed to H Okuno.

139 records · Page 8Linked to original sources

How to remove, process, and study the temporal bone with the entire eustachian tube and its accessory structures: a method for histopathological study.

A very important contribution to the study of otitis media, one of the diseases most often seen in pediatric patients, is the collection and study of temporal bone specimens which include the entire Eustachian tube. During the last few years, we have collected, processed, and studied more than 100 such specimens. Through these experiences, our technique has become so refined that we have some important suggestions to make to otologists who are interested in the histological study of otitis media as well as in the pathology of the Eustachian tube and its relation to middle ear abnormalities. This report describes the method we have found to be most successful for the study of Eustachian tube abnormalities and their relationship to middle ear effusion.

Eustachian Tube↗

Purification and properties of glucose-6-phosphate dehydrogenase from Bacillus stearothermophilus.

Glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP+ 1-oxidoreductase, EC 1.1.1.49) from the thermophilic bacteria, Bacillus stearothermophilus, was purified and its properties were examined. The enzyme was shown to consist of four identical subunits, each of about Mr 50,000. This enzyme utilized both NADP+ and NAD+ as cofactors, and the maximum velocity for both cofactors was similar. However, the Km values were quite different from each other, being 0.016 and 1.64 mM for NADP+ and NAD+, respectively. From the analysis of sulfhydryl groups it was shown that there is one sulfhydryl group and one disulfide bridge per subunit. This sulfhydryl group had no reactivity with 5,5'-dithiobis(2-nitrobenzoic acid) in the absence of guanidine hydrochloride. The enzyme showed a remarkable thermostability as well as storage stability.

Amino Acids↗

[Clinical experience with cefotetan in the treatment of infections of children].

Twenty-five patients in hospital mainly with lower respiratory tract infections and urinary tract infections were treated with cefotetan (CTT). The drug was given intravenously in a dose of 20 mg per kg body weight 1 to 3 times per day. The response to treatment was satisfactory in the 21 patients (84%). There was slight changes in liver function tests in 2 patients and exanthem in 1 patient. CTT appears to be an effective antibiotic for the treatment of children with bacterial infection.

Adolescent↗

Retroperitoneal haematoma due to ruptured microaneurysm of the pancreaticoduodenal artery.

A case of retroperitoneal haematoma due to a ruptured microaneurysm of the posterior superior pancreaticoduodenal artery in a 61 year old man is described. Ultrasonography and computed tomography revealed cystic masses near the gall-bladder. Selective coeliac angiography disclosed a microaneurysm of the posterior superior pancreaticoduodenal artery. Surgical extirpation of the cystic masses was performed, and the histological finding was an encapsulated old haematoma.

Aneurysm, Ruptured↗

Genotypes of hepatitis C virus in Guangxi province, southern China.

Hepatitis C virus (HCV) has been subdivided into at least four genotypes, and the prevalence of each genotype has been reported to differ widely in different countries. Of 304 patients with chronic liver diseases (68 with chronic hepatitis, 50 with liver cirrhosis and 186 with hepatocellular carcinoma) from Guangxi Province in southern China, only 9 (3.0%) had antibodies to HCV as determined by a second-generation enzyme immunoassay with a cut-off index of 2.0 or more. The HCV genotypes of these nine cases were examined using polymerase chain reaction with type-specific primers deduced from putative core gene. Seven of the nine cases had type II infection and the other two cases showed double infection with types II and IV. These findings indicate that the predominant HCV genotype in the Guangxi area is type II, as is the case in Japan, although the prevalence of HCV infection in patients with chronic liver diseases is much lower.

Adolescent↗

Electrically evoked auditory brainstem response by direct electrical stimulation to the cochlear nerve in acoustic neuroma patients.

The electrically evoked auditory brainstem response (EABR) was recorded by direct electrical stimulation of the cochlear nerve in 8 acoustic neuroma patients. The EABR by electrical stimulation of the cochlear nerve at the fundus of the internal auditory canal was almost similar to those previously reported from cochlear implant patients in waveform morphology and wave latencies. However, the wave corresponding to wave II in human auditory ABR was not recorded in the EABRs by stimulation of the distal part of the intracranial cochlear nerve. These results suggest that the cochlear nucleus does not contribute to the generation of wave II in ABR.

Adult↗

A method for the histopathological analysis of the temporal bone and the eustachian tube and its accessory structures.

A very important contribution to the study of otitis media, one of the diseases most often seen in pediatric patients, is the collection, processing, and study of the specimens of the temporal bone and the entire eustachian tube. During the last few years, we have collected, processed, and studied 100 such specimens, and through these experiences our technique has become refined. We now have some important suggestions for otologists interested in the histological study of otitis media as well as in the pathology of the eustachian tube and its relation to middle ear abnormalities. This report details the most successful method for the study of eustachian tube abnormalities and their relationship to middle ear effusion.

Dissection↗

Different expression of esterase variants in rat hepatic and hepatoma-derived cell lines detected by electrophoresis.

Esterases in nine rat hepatic and hepatoma-derived cell lines and normal rat liver homogenate were detected by polyacrylamide gel electrophoresis coupled with active staining with alpha-naphthyl acetate or butyrate as a substrate. The esterase band patterns of the non-cancerous and oncogene-transformed cell lines were alike, but different from those of hepatoma cell lines and normal rat liver homogenate. The former groups of cells might have completely lost the characteristics of rat liver parenchymal cells, or else they might have their origin at cells other than liver parenchyma. The esterase patterns of the hepatoma cell lines (e.g., McA-RH7777) and the normal rat liver highly resembled with each other, exemplifying the slight biochemical deviation of cancer from normal cells. However, two-dimensional electrophoretogram for the McA-RH7777 cell line showed a prominent esterase spot (pI 6.0-M(r) 110 kDa) that was lacking in the normal liver. This result indicates that there is invariably some change in esterase expression between the cancer cells and the normal liver cells.

Animals↗

Anatomy of the round window. A histopathological study with a graphic reconstruction method.

The round window was studied in normal adult and infant temporal bones to provide a knowledge base for the study of congenital anomalies of the round window, and to determine whether the round window develops postnatally. Fifty-three temporal bones were studied. Specimens were processed histologically, sectioned horizontally, stained with hematoxylin and eosin, and studied under the light microscope and microprojector. A special method of graphically reconstructing the round window was developed for this study, and was used to define the contour, area, and angle of the round window. We found that the round window is fan shaped. The area of the superoposteriorly located horizontal part (three-sevenths of the round window) and of the inferoanteriorly located vertical part (four-sevenths of the round window) totals approximately 2.29 mm2. In addition the angle between the plane of the tympanic sulcus and the vertical part of the round window was measured, and found to average 73.3 degrees. Lastly, the round window was found not to develop postnatally.

Adult↗