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Biomedical subjects

T Harada

Publications and source records attributed to T Harada.

At least 721 records · Page 40Linked to original sources
PubMed1990

Observations of the anterior epitympanic recess in the human temporal bone.

The structure of the anterior epitympanic recess was examined in 50 human temporal bones. The recess was found in 48 temporal bones (96%) and showed three different structural types. In type A, the least developed type (38%), a main cavity is seen above the tensor tympanic fold. The recess is divided into two cavities by the tensor tympanic fold, which stretches to the anterosuperior tympanic tegmen in type B, the intermediate type (40%). The tensor tympanic fold is fused with the superior mallear fold in type C, the best-developed type (18%), with the recess being contiguous with the eustachian tube. The shape of the anterior epitympanic recess is influenced by the ratio between the cavities above and below the tensor tympanic fold, ie, by the embryologic development of the saccus anticus and the anterior saccule of the saccus medius. The structural variations in this recess must be kept in mind during the surgical management of middle ear diseases.

Ear, Middle↗
PubMed1990

Osteoma of the middle ear. Report of a case.

Osteomas of the middle ear are rare. We report a case of a 7-year-old boy with osteoma originating from the pyramidal eminence, combined with congenital cholesteatoma. The osteoma and cholesteatoma were successfully removed by tympanomastoidectomy. The long process of the incus and the superstructure of the stapes disappeared. The body of the incus was sculpted and used as a columella. Histopathologically, the osteoma was much the same as an external auditory canal osteoma. The possibility of a primary congenital origin of this neoplasm is suggested.

Child↗
PubMed1990

Computer-aided three-dimensional reconstruction of the osseous and membranous labyrinths.

In order to obtain an adequate knowledge of the stereoscopic anatomy of the temporal bone, it is very useful to make three-dimensional reconstructions of the bone. By using the histological sections of a human temporal bone processed for routine evaluation, we have undertaken computer-aided reconstruction of the osseous and the membranous labyrinths, as well as the inner ear sensory organs. Reconstructions were done either separately or simultaneously. Owing to the "semitransparent display" function of the computer system, it was possible to observe the reconstructed membranous labyrinth through the simultaneously reconstructed osseous labyrinth, and the sensory organs through the membranous labyrinth. The results were satisfactory for understanding the spatial relationships among these structures. We also attempted computer-aided measurements of the reconstructed sensory organs and calculated the length of the organ of Corti and the angle between the saccular and the utricular maculae.

Computer Simulation↗
PubMed1990

Adherence of Haemophilus influenzae to nasal, nasopharyngeal and buccal epithelial cells from patients with otitis media.

Since mucosal colonization may be an important determinant in the pathogenesis of otitis media with effusion (OME), we studied the adherence of Haemophilus influenzae (HI) to human nasal, nasopharyngeal, and buccal mucosal cells obtained from patients with OME. Non-typeable HI adhered in significantly greater numbers than type b HI. HI bacteria adhered to both nasal and nasopharyngeal mucosal cells in significantly greater numbers than to buccal ones. Non-typeable HI adhered to the epithelial cells from children with chronic sinusitis in more significant numbers than did those from children without chronic sinusitis. These results indicate that non-typeable HI adhere more readily to epithelial cells and that the nasal and nasopharyngeal mucosa may be an important route for HI infection in OME.

Adolescent↗
PubMed1990

Uptake of horseradish peroxidase by the middle ear mucosa in experimentally induced otitis media.

Electron microscopy was used to study the characteristics of uptake of the protein tracer, horseradish peroxidase (HRP), by the middle ear mucosa of chinchillas. Two types of experimental otitis media were used: serous otitis media (SOM) produced by eustachian tube obstruction and purulent otitis media (POM) produced by inoculation of Streptococcus pneumoniae type 7F. HRP was placed in each tympanic bulla for either 1 min or 10 min. In the 1-min installation of HRP, the degree of HRP uptake was higher in SOM and POM animals than in control animals. Following the 10-min installation of HRP, the degree of HRP uptake was higher in SOM and POM animals than in control animals. Following the 10-min installation of HRP, the degree of tracer uptake was almost the same as among the control, SOM and POM animals. The mechanism of uptake was pinocytosis. In another experiment, 5-hydroxydopamine (mol. wt. 256) was used as a small tracer placed into the bulla to examine the permeability of epithelial tight junctions. No labelling of reaction product was observed in the tight junctions of the control, SOM or POM animals. These findings suggest that otitis media increases the uptake of HRP by pinocytosis and that epithelial tight junctions remain intact in inflammation of the middle ear cavity.

Animals↗
PubMed1990

Metabolic changes following gastroplasty in Prader-Willi syndrome--a case report.

A vertical banded gastroplasty was performed in an adult female patient with Prader-Willi syndrome in an attempt to prevent the metabolic deterioration caused by polyphagia. After her operation, the patient felt satiated with the scheduled amount of food and one month later, her fasting blood sugar concentration (FBS) decreased from 521 to 125 mg/dl, and her urinary sugar excretion (US) from 257 to 9 g/day. Both glucose tolerance and insulin secretion were also improved. However, these parameters subsequently became worse after dietary control was lost since the surgical procedure alone was unable to continue to suppress the insatiable desire to eat food. Both her glucose tolerance and insulin secretion by the 31st postoperative month were better than before the surgery, but worse than at one month after the surgery. At the end of the surgery, but worse than at one month after the surgery. At the end of the 34th postoperative month, even under the temporary administration of 0.625 mg/day of glibenclamide, her FBS was 158 mg/dl and US, 38.1 g/day. Her body weight had also increased to over her preoperative value. Based on these results, we conclude that the effect of gastroplasty to prevent metabolic deterioration in our patient with Prader-Willi syndrome gradually diminishes.

Adult↗
PubMed1990

A case of idiopathic portal hypertension after renal transplantation.

A case of idiopathic portal hypertension (IPH) developing after renal transplantation is reported. A 33-year-old Japanese male who had undergone renal transplantation 8 years previously was transferred to our hospital because of hematemesis from ruptured esophageal varices. He had no history of any liver disease before the renal transplantation, but had a history of receiving blood transfusion. Abdominal computed tomography (CT) and ultrasonography revealed marked splenomegaly and collateral channels, but no obliteration which might cause portal hypertension in the hepatic or portal vein. No findings suggestive of hepatitis or liver cirrhosis were found either macroscopically on laparoscopy or by liver biopsy. Light microscopic study of the liver biopsy specimen showed mild periportal fibrosis, inconspicuous portal branches in the most peripheral tracts, but no pseudolobule formation or piecemeal necrosis. However collagen deposition was found in the perisinusoidal space and partly in intercellular space on electron microscopy. We consider that the development of portal hypertension in this case is responsible for the collagen deposition, which may be related to the administration of azathioprine after renal transplantation. There are few reports on IPH after renal transplantation, and it is stressed that a lower amount of azathioprine than previously reported may induce IPH under such conditions.

Adult↗
PubMed1990

Intraoperative real-time ultrasonic scanning for microwave coagulation of the prostate.

Nine patients with severe dysuria caused by prostatic cancer received prostatic microwave coagulation under intraoperative real-time ultrasonic scanning. During the procedure, the microwave applicator was clearly observed, and the coagulation region appeared as an hyperechoic area compared to the noncoagulated region. Intraoperative real-time ultrasonic scanning allowed safer and more efficacious application of prostatic microwave coagulation.

Adult↗
PubMed1990

Squamous cell carcinoma-antigen for detection of squamous cell and mucoepidermoid carcinoma after primary treatment: a preliminary report.

This study evaluated the efficacy of using the periodic measurement of the serum level of squamous cell carcinoma antigen (SCC-antigen) for determining the local recurrence and/or metastasis of squamous cell and mucoepidermoid carcinomas after primary treatment. It was found that at the time of clinical recognition of recurrence, the SCC-antigen level was normal, but metastasis to regional lymph nodes or to remote organs generally was accompanied by an increase of SCC-antigen. Changes in the SCC-antigen level with mucoepidermoid carcinoma seemed to be less sensitive than with squamous cell carcinoma.

Aged↗
PubMed1990

A case of recurrent aural cholesteatoma extending into the middle cranial fossa.

A case of aural cholesteatoma extending into the middle cranial fossa is presented. The cholesteatoma appears to have recurred in an ear in which a radical mastoidectomy had been performed more than 40 years earlier. The patient complained only of a vague sensation of heat in the head and did not manifest distinct neurologic signs or symptoms. The cholesteatoma was removed through an extended endaural approach. Extension of aural cholesteatoma beyond the confines of the temporal bone appears to be quite unusual.

Adult↗
PubMed1990

Recombinant human bone morphogenetic protein induces bone formation.

We have purified and characterized active recombinant human bone morphogenetic protein (BMP) 2A. Implantation of the recombinant protein in rats showed that a single BMP can induce bone formation in vivo. A dose-response and time-course study using the rat ectopic bone formation assay revealed that implantation of 0.5-115 micrograms of partially purified recombinant human BMP-2A resulted in cartilage by day 7 and bone formation by day 14. The time at which bone formation occurred was dependent on the amount of BMP-2A implanted; at high doses bone formation could be observed at 5 days. The cartilage- and bone-inductive activity of the recombinant BMP-2A is histologically indistinguishable from that of bone extracts. Thus, recombinant BMP-2A has therapeutic potential to promote de novo bone formation in humans.

Animals↗
PubMed1990

IgA affinity to ssDNA or endothelial cells and its deposition in glomerular capillary walls in IgA nephropathy.

Autoantibodies to glomerular components may be pathogenetic in IgA nephropathy. We studied sera from 32 IgA nephropathy patients, 35 normal controls and 102 patients controls with other forms of glomerulonephritis for IgA isotype affinity to endothelial cells, denatured DNA (ssDNA), murine laminin, and cardiolipin measured by ELISA. Compared to the normal controls, patients with IgA nephropathy had significantly elevated IgA with affinity to endothelial cells (P = 0.01) and ssDNA (P = 0.04), but not to murine laminin or cardiolipin. Furthermore, serum IgA with affinity to ssDNA, but not to endothelial cells, was associated with the presence of IgA deposited in the glomerular capillary walls (P = 0.011), an indicator of poor prognosis in patients with IgA nephropathy. Therefore, IgA with affinity to ssDNA may represent an autoantibody with pathogenetic significance in IgA nephropathy.

Adult↗
PubMed1990

Iodine-131 uptake in a patient with thyroid cancer and rheumatoid arthritis during acupuncture treatment.

A patient with thyroid carcinoma had abnormal accumulation of I-131 in the areas of both feet and hands on whole body scan. The sites of abnormal accumulation of I-131 were similar to those on bone scintigraphy. The radiographic examination of the lesions showed characteristic findings of rheumatoid arthritis, and the presence of small gold needles for acupuncture treatment was demonstrated. There were no findings of bone metastases. Although the mechanism of accumulation of I-131 in this patient is unknown, interpreters of I-131 whole body scintigraphs should keep this case in mind when acupuncture treatment has been done. The authors can only speculate on a common blood flow mechanism for enhanced HMDP and I-131 uptake in this arthritic patient who had been treated by acupuncture.

Acupuncture Therapy↗
PubMed1990

Blood component induction of cerebral vasospasm.

The role of blood components in cerebral vasospasm was evaluated using an in vivo canine model. An intracisternal injection of 5 ml of washed red blood cells (RBCs) and platelet-rich plasma (PRP) resulted in acute vasospasm of the basilar artery as seen by angiography. This was comparable with the degree of vasospasm induced by an injection of the same amount of whole blood. Repeated injections of blood components or whole blood on Days 1 and 3 induced chronic vasospasm, as shown by angiography on Day 7. Results clearly indicate that chronic vasospasm was produced by RBCs and PRP, and it was in a dose-dependent manner with increasing concentrations of RBCs (hematocrit: 30, 50, and 70%). The vasospasm induced by both components closely reproduced that seen with whole blood. Neither acute nor chronic vasospasm induced by blood component injection was associated with clot formation in the subarachnoid space, as confirmed by an autopsy. These results suggest that the extravasation of RBCs and PRP into the subarachnoid space produces cerebral vasospasm by mechanisms independent of blood clot formation.

Animals↗
PubMed1990

A rat femoral artery model for vasospasm.

A new animal model for vasospasm using rat femoral artery has been developed. Whole blood, washed erythrocytes, or leukocytes in platelet-rich plasma were selectively applied to the adventitial surface of the femoral artery for 7 days in 15 rats, after which the vessels were perfusion-fixed and examined by light and transmission electron microscopy and immunohistochemistry. As compared with matched control arteries, there was a prominent reduction in luminal cross-sectional area after 7 days in vessels exposed to whole blood or washed erythrocytes, but not in those exposed to leukocytes in platelet-rich plasma. In arteries with luminal narrowing, light and transmission electron microscopy demonstrated marked morphological changes throughout the vessel wall similar to those seen in cerebral vasospasm after subarachnoid hemorrhage. Immunohistochemistry disclosed a prominent loss of immunoreactive actin in smooth muscle cells of arteries exposed to whole blood or erythrocytes. To assess the time course of arterial narrowing in this model, whole blood was selectively applied to the adventitial surface of femoral arteries in 23 rats for periods from 2 to 20 days. As compared with control arteries, arterial narrowing was variably present at 2 days, progressively increased by 5 days, was maximal at 7 to 10 days, and returned to near control levels by 20 days. The presence and severity of ultrastructural changes in vessel wall corresponded to the degree of arterial narrowing over time. These results suggest that chronic narrowing in rat femoral artery exposed to periadventitial blood is analogous to that observed in cerebral arterial vasospasm after subarachnoid hemorrhage. This new model represents a simple and reliable means to investigate pathogenic mechanisms and potential therapies for vasospasm.

Animals↗
PubMed1990

Motion analysis of the cervical spine in athetoid cerebral palsy. Extension-flexion motion.

Frequently instability and premature onset of spondylosis of the cervical spine are found in athetoid cerebral palsy (CP) patients. These structural abnormalities appear to be related to athetoid motion of the neck in CP. Through motion analysis, the authors aimed to clarify the abnormalities of cervical motion that could precipitate structural abnormalities. The gross characteristic feature of cervical motion in athetoid CP is "whip movement." Both velocity and acceleration during extension-flexion motion were greater than in normal subjects, especially at the upper cervical levels. Also, a sudden increase in velocity and acceleration occurred during rapid motions at certain levels, followed by a larger range of motion of the cervical spine. Such kinematic abnormalities were thought to generate a greater shearing force and bending moment exerted on the corresponding cervical articulations-discs and facets. Olisthetic instability often accompanied disc degeneration at the upper cervical levels. A large range of extension--flexion motion of the cervical spine, analogous to a cantilever, caused a repeated bending moment of extraordinary magnitude and was regarded as a precipitative factor for disc degeneration and osteophytosis common at the middle and lower levels of the disc.

Adult↗
PubMed1990

Expression of leukocyte common antigen (CD45) on various human leukemia/lymphoma cell lines.

CD45 antigen (leukocyte common antigen), a unique and ubiquitous membrane glycoprotein with a molecular mass of about 200 kDa, is expressed on almost all hematopoietic cells except for mature erythrocytes. However, the biological function of this glycoprotein still remains to be resolved. In order to clarify the role of CD45 antigen in hematopoietic cell differentiation and function, its expression on human leukemia/lymphoma cell lines was studied by membrane immunofluorescence. Thirty-eight established cell lines were analyzed using T29/33, a monoclonal antibody (MoAb) that recognizes the common epitopes of this glycoprotein molecule. Conventional cell marker studies were also carried out on these cell lines to compare their CD45 expression. It was shown that CD45 expression varies among B-lineage cells depending on cell differentiation, in contrast to its stable expression on leukemic T cell (6/6, positive) and myeloid (5/5, positive) lineage cell lines. On the other hand, only two out of six histiomonocytoid lineage cell lines were positive. Human T cell leukemia/lymphoma virus type I (HTLV-I)-associated T cell lines derived from peripheral blood leukocytes of patients with adult T cell leukemia/lymphoma (ALT/L) in Japan did not express CD45 on their cell surface. Taken together, these observations suggest that CD45 has a functional role in hematopoietic cell activation and differentiation.

Adult↗