Search PubMed⌕ Search

Biomedical subjects

T Ogata

Publications and source records attributed to T Ogata.

At least 379 records · Page 21Linked to original sources
PubMed1989

Effects of endolymphatic mastoid shunt operation for patients with Menière's disease.

During the past 10 years, the endolymphatic mastoid shunt operation was carried out on 108 patients with Meniere's disease: 54 men and 54 women between 22 and 72 years old. According to criteria AAOO proposed in 1972, 86 cases (79.6%) belonged to class A, 19 cases (17.7%) to class B and 3 cases (2.7%) to class C. Forty patients took the body sway test before and after the operation. Four of the 40 patients were found to have Meniere's disease on the contralateral side within 12 months after the operation and one patient was found to have a complicating psychogenic disease. The abnormal body sway had recovered 2 to 9 months after the operation, but the medical treatment could not be stopped during this period. The average hearing gain after the operation was 21.3 +/- 14.4 dB; that for the patients with a short period of illness (within 23 months of the first onset to the operation) was 25.2 +/- 14.5 dB and that for the patients with a longer period of illness (over 24 months) was only 13.8 +/- 10.6 dB.

Adult↗
PubMed1989

The testicular lesion and sexual differentiation in congenital lipoid adrenal hyperplasia.

Congenital lipoid adrenal hyperplasia results in deficient virilization of genetic male infants, indicating that gonadal testosterone biosynthesis is impaired in such patients. In order to better define the characteristics of the gonadal lesion, we studied a Japanese genetic male infant with congenital lipoid adrenal hyperplasia who underwent bilateral orchiectomy at 14 months of age. The basal serum testosterone was low before and after orchiectomy (6.6 +/- 1.1 vs. 9.5 +/- 1.3 ng/dl), though it was higher at 9 days of age (30 ng/dl). A stimulation test with human chorionic gonadotropin at 12 months of age yielded no testosterone response (7----less than 5 ng/dl). At the time of the surgical intervention, the external genitalia were completely female but Wolffian duct derivatives (epididymides and vasa deferentia) were well developed. The microscopic examination of the testes revealed an increased number of Leydig cells which were filled with abundant lipoid material.- The above data demonstrate that the fetus produced a sufficient amount of testicular testosterone for a male Wolffian duct development. This indicates a quantitative difference in androgen requirements for the male sexual development of the external genitalia and the Wolffian ducts.

Adrenal Hyperplasia, Congenital↗
PubMed1989

[Histopathological study of juvenile thyroid carcinoma].

We have examined 12 cases of juvenile thyroid carcinoma histopathologically. The characteristics uncovered of juvenile thyroid carcinoma have been summarized below. 1) The predominant histological type was a papillary carcinoma with abundant follicular components. Which was inclined to show trabecular and solid pattern. 2) The growth pattern was highly infiltrative, showing a frequent extrathyroidal extension, a wide intrathyroid spread, and a severe involvement of the lymph nodes. 3) Many psammoma bodies were observed frequently. 4) Remarkable lymphocytic infiltration was seen in the thyroid around the tumor, and in one case it resembled chronic thyroiditis. In addition, a case of a multicentric papillary carcinoma showed unusual histological features.

Adenocarcinoma↗
PubMed1988

Lymphocytic infiltration in juvenile thyroid carcinoma.

In this study, the significance of lymphocytic infiltration in juvenile thyroid carcinoma is clarified. We examined nine patients younger than 20 years of age. Histopathologically, there was good correlation between lymphocytic infiltration and the development and spread of carcinoma. It is believed that lymphocytic infiltration around the tumor is an immunologic reaction induced by antigens from the carcinoma itself, and also that the reaction may progress according to tumor development. Immunocytochemically, we determined what type of inflammatory cells infiltrated the thyroid and demonstrated HLA-DR expression in the cancer cells. These findings are similar to autoimmune thyroiditis in which antibody-dependent cellular cytotoxicity (ADCC) works as a main immunomechanism.

Adolescent↗
PubMed1988

Immunoaffinity purification of human erythrocyte prolidase.

A procedure including immunoaffinity gel chromatography of an immobilized monoclonal antibody was used to isolate human erythrocyte prolidase (EC 3.4.13.9). The monoclonal antibody was developed against liver prolidase and the antibody recognized the erythrocyte enzyme. The purification procedure included three steps of DEAE cellulose (batcher), immunoaffinity gel chromatography and gel filtration column chromatography. The overall recovery was approximately 20% and the specific activity of the purified preparation was approximately 260 U/mg of protein, a value exceeding that obtained using conventional procedures.

Chromatography, Affinity↗
PubMed1988

Radiolabeled monoclonal antibody 15 and its fragments for localization and imaging of xenografts of human lung cancer.

Monoclonal antibody (MAb) 15 and its F(ab')2 and Fab fragments were radioiodinated, and their biodistribution and imaging were compared in BALB/c nude mice bearing a xenograft of a human lung cancer (TKB-2). Association constants for 125I-labeled MAb 15 IgG, F(ab')2, and Fab were 1.9 X 10(9), 1.8 X 10(9), and 3.7 X 10(8) M-1, respectively. Immunoreactive fractions ranged from 0.59 to 0.50. Cultured TKB-2 cells expressed 1.1 X 10(4) binding sites/cell for MAb 15 IgG in vitro. The binding of a control antibody and the binding of its fragments to TKB-2 cells were less than 3% of the input doses. The mice with the TKB-2 tumors were given simultaneous injections of 10 microCi of 131I-labeled MAb 15 or its fragments and 10 microCi of 125I-labeled control IgG or its fragments. With MAb 15 IgG, the percentage of the injected dose bound per gram of tissue (ID/g) of the tumor was 3.68% at day 7, when the localization index (LI) was 4.38. At day 2 after MAb 15 F(ab')2 injection, 1.12% of the ID/g was localized in the tumor and the LI was 3.04. After MAb 15 Fab injection, the percentage of the ID/g of the tumor was 0.31% and the LI was 2.58 at day 1. MAb 15 IgG, F(ab')2, and Fab cleared from the blood early, with a half-life of 33, 16, and 9 hours, respectively. The distributions of MAb 15 and its fragments in the normal organs did not differ from those of the control. Radioimaging with 100 microCi of 131I-labeled MAb 15 and its fragments showed that 42%, 44%, and 32% of the total-body count were localized in the tumor with IgG at day 7, F(ab')2 at day 2, or Fab at day 1, respectively. Because the radioactivity remaining in the tumor with Fab was low, the image was insufficient. Throughout the period, less than 10% of the control IgG and its fragments remained in the tumor. Microautoradiography confirmed the binding of MAb 15 and its fragments to the tumor cells. In this study the F(ab')2 was the best compromise between the slowly cleared IgG and the poorly localized Fab in tumor imaging.

Animals↗
PubMed1988

Seroepidemiological study of infection with West Nile virus in Karachi, Pakistan, in 1983 and 1985.

The prevalence of West Nile (WN) virus infection in Karachi, Pakistan, was unknown until 1982. It had been noticed that there were more than a few patients with encephalitides in Karachi, and it was supposed that Japanese encephalitis (JE) cases would be found among them. Therefore, a seroepidemiological study was conducted to define the prevalence of WN virus infection and the possible occurrence of JE virus infection in the Karachi area. Prevalences of haemagglutination inhibition (HI) and neutralization (NT) antibodies against WN virus were studied among 81 serum samples (in July, 33 samples; in September, 48) during 1983, and among 156 paired serum samples that were collected twice, in July and October of 1985. Nearly the same antibody-positive rates were obtained in July of both years (1983: HI 55%; 1985: HI 53%; NT 50%); the rates increased slightly during September/October (1983: HI 65%; 1985: HI 59%, NT 54%). Among 156 paired samples in 1985, 20 (13%) and 12 (8%) showed positive- or negative-antibody conversion between July and October. Two serum samples from each of 156 residents obtained in July had a significantly higher NT antibody titre against JE virus than against WN virus (in case 1, JE 1:80, WN less than 1:10; in case 2, JE 1:40, WN less than 1:10). This is the first report to show the prevalence of WN virus infection in Karachi, Pakistan.

Antibodies, Viral↗
PubMed1988

Scanning electron-microscopic study on the three-dimensional structure of motor endplates of the slow (tonic) muscle fibers in the frog, Rana n. nigromaculata.

The three-dimensional organization of the motor endplates of the slow fibers of the rectus abdominis muscle in the Japanese meadow frog (Rana nigromaculata nigromaculata Hallowell) is visualized by use of a field-emission scanning electron microscope after removal of connective tissue components by HCl hydrolysis. Clusters of shallow oval depressions approximately 1-3 microns in diameter are seen in the postsynaptic membrane at intervals of about 150 microns. On the surface of these depressions, a few low bulges of postsynaptic membrane are irregularly arranged. Terminal boutons, approximately 1-3 microns in diameter, occur along the length of nerve branches and terminals and fit into the shallow oval depressions of the postsynaptic membrane. The Schwann cells covering the terminal branches exhibit a simpler organization than those in twitch fibers.

Animals↗
PubMed1988

Computed tomography in the early detection of congenital lipoid adrenal hyperplasia.

This paper describes the successful use of abdominal computed tomography (CT) scan in diagnosing congenital lipoid adrenal hyperplasia in a Japanese male with no virilization at 9 days of age. The CT unequivocally delineated massively enlarged adrenal glands of fat-tissue attenuation, enabling early replacement therapy.

Adrenal Hyperplasia, Congenital↗
PubMed1988

Protogonyaulax cohorticula, a toxic dinoflagellate found in the Gulf of Thailand.

Two clones of Protogonyaulax cohorticula were isolated from the Gulf of Thailand. The extracts of these clones killed mice with typical signs of paralytic shellfish poisoning. The toxicities corresponded to those of strongly toxic clones of P. tamarensis. In the HPLC and electrophoretic analyses, gonyautoxins and saxitoxin were detected. About 80% of the toxins consisted of gonyautoxin I. These results show that P. cohorticula is a toxic species of Protogonyaulax and that it is at least one of the causative organisms of paralytic shellfish poisoning in Thailand.

Animals↗
PubMed1988

Long-term results of jejunal replacement of the esophagus.

Since 1969, jejunal interpositions have been carried out in 19 patients for esophageal replacement. A segment of the upper jejunum was used to bridge the gap in the right thoracic cavity. The distal esophagus and its sphincteric mechanism was preserved in all but four patients, who had peptic strictures. Early postoperative complications such as total necrosis of the graft, perforation of the graft, and anastomotic leak developed in three patients (16%). There were no operative deaths but there were two later deaths (11%). We were able to follow 12 patients over a long term. Among these 12 patients there were two anastomotic strictures, one of which was dilated successfully by bouginage, and one marked redundancy of the jejunum which necessitated surgical correction. Both height and weight were lower than -2 SD on a Japanese standard growth curve in two patients who had anastomotic strictures. Transient stagnation of swallowed barium at the lower esophagus was the common finding; it was observed in seven cases (58%). Only three patients (25%) complained of occasional feelings of delay in swallowing. Stagnation with a mildly redundant jejunum was the common radiologic finding in these three patients. Reflux of the gastric content into the esophagus did not occur. All the patients, except one who still has dysphagia due to anastomotic stricture, can eat anything they wish at almost normal speed. These long-term results indicate that jejunal interposition with preservation of the lower esophagus is a recommendable procedure for esophageal replacement.

Adolescent↗
PubMed1988

Atypical Prader-Willi syndrome with severe developmental delay and emaciation.

A young boy showed features of Prader-Willi syndrome including hypotonia, cryptorchidism, a mildly dysmorphic facial appearance, a high-arched palate and an open triangular-shaped mouth, but had additional symptoms such as simian creases and multiple joint ankylosis in early infancy. Deletion of the long arm of chromosome 15(q11.2 to q13) was recognized. A muscle biopsy specimen showed variation in fiber size with hypertrophic type 1 fibers, type 2 fiber smallness, type 2B fiber paucity and an increased number of type 2C fibers. At the age of 4 1/2 years, he still showed severe developmental delay with severe muscle hypotonia, weakness and emaciation.

Child, Preschool↗
PubMed1988

An unusual case of solid hamartoma in the liver.

An unusual case of solid hepatic hamartoma, which could not be correctly categorized under the WHO classification, is reported. The well defined, solid nodular lesion, arising in the anterior edge of the left hepatic lobe, was found in a 15-month-old female infant. The lesion was composed of irregularly shaped yellow islands of parenchyma and white-gray nodules of fibrous stroma of various sizes, which were intermingled revealing a mosaic pattern. Prominent bile ductal proliferation was observed histologically in the fibrous stroma, associated in parts with dense or loose periductal bundles and vascular proliferation. The stromal proliferation seemed to result in erosion of the islands of differentiated parenchymal cells with no regeneration. Alpha-fetoprotein was demonstrated immunohistologically in the parenchymal cells of the lesion. From these findings, the essential component of this solid hamartoma was thought to be markedly proliferating bile ducts associated with periductal fibrosis, resulting in a fibroadenomatous pattern.

Bile Ducts↗
PubMed1988

Blood vascular organization of the human appendix: a scanning electron microscopic study of corrosion casts.

Blood vascular beds of the human appendix were reproduced with a methacrylate casting medium and observed with a scanning electron microscope. The appendix received some small afferent arterial branches of the appendicular artery. These small arterial branches pierced the muscular layer and reached the submucosal plexus. Small arterioles arising from this plexus, climbed the mucosa and formed honeycomb-like capillary meshes at the luminal surface level. These capillaries were drained by the collecting veins, which descended the mucosa and joined the submucosal plexus. The large efferent veins arising from the submucosal plexus passed through the muscular layer and continued with the appendicular vein. In the mucosal and submucosal layers, several spherical basket-like casts of the germinal center (lymphoid follicle) were seen. In the parafollicular region (primary follicle), casts of postcapillary venules with prominent surface undulations were relatively frequently observed.

Adult↗
PubMed1988

Structure of motor endplates in the different fiber types of vertebrate skeletal muscles.

The number and localization of vertebrate motor endplates on the muscle fiber, and their structure, vary according to phylum and species, and among the different fiber types in a given species. Vertebrate skeletal muscle fibers are classified into two major groups: the twitch (fast) and the slow (tonic) fibers. The twitch fiber has straight Z-lines and a well developed T-SR system, and is singly innervated with en plaque (plate-like) type motor endplate. The twitch fibers are further subdivided into three types: the red (mitochondria-rich), intermediate (mitochondria-moderate) and white (mitochondria-poor) fibers. The motor endplate of the white fiber is large and has a complicated structure, that of the red fiber is small and less complicated, and that of the intermediate fiber possesses intermediate characteristics. The slow fiber has zigzag Z-lines and poorly developed sarcoplasmic reticulum (SR), and is multiply innervated with en grappe (grape-like) type motor endplates. The morphological features of the motor endplate in each of these fiber types of the mammalian, avian, reptilian, amphibian, and fish skeletal muscles are reviewed. Special emphasis has been placed on the three-dimensional structure of the motor endplates of the different fiber types as observed by high-resolution scanning electron microscopy.

Amphibians↗