PubMed Health⌕ Search

Biomedical subjects

R Katoh

Publications and source records attributed to R Katoh.

At least 55 records · Page 3Linked to original sources
PubMed1994

Cell function during chondrogenesis and osteogenesis induced by bone morphogenetic protein enclosed in diffusion chamber. Biochemical studies on native products derived from outside differentiating cells.

A diffusion chamber containing rabbit bone morphogenetic protein (BMP) was implanted in the abdominal muscle of a Sprague-Dawley rat. Outside of the chamber, cartilage differentiated one to two weeks after implantation, and bone replaced the cartilage three to four weeks after implantation. The interstitial fluid inside the chamber contained only biologic substances produced by cells proliferating and differentiating outside of the chamber. To investigate the cell function during chondrogenesis and osteogenesis, alkaline phosphatase activity and the amounts of S-100 alpha protein, S-100 beta protein, creatine kinase subunits M (CK-M), creatine kinase subunits B (CK-B), hyaluronic acid (HA), and chondroitin sulfate (CS) were measured in the supernatant of interstitial fluid inside the chamber. Alkaline phosphatase activity increased two to four weeks after implantation. The amount of S-100 beta protein acutely increased during the fourth week. The amount of CK-B also increased during the fourth week. The increased levels of HA and CS were also observed after two to four weeks. The examination of such native products may help not only to clarify the mechanisms of cartilage and bone development, but also to develop a sensitive bioassay for BMP.

Alkaline Phosphatase↗
PubMed1994

[A case of traumatic diaphragmatic hernia repaired 40 years after the injury].

A 65-year-old male complaining dyspnea on exertion and epigastric discomfort was diagnosed to have left traumatic diaphragmatic hernia elsewhere and referred to Keio university Hospital for treatment. He had thoracicio-abdominal trauma which was conservatively treated, 40 years ago. Because he was symptomatic and the possibility of future strangulation could not be denied, surgical repair of the hernia was performed. The defect in the diaphragm was too large to be directly sutured and it was repaired with GORE-TEX patch. The gastric fundus partially prolapsed in the paraesophageal region, but the diaphragm was repaired quite satisfactorily otherwise. Pulmonary function and dyspnea on exertion improved.

Aged↗
PubMed1993

Alteration of the basement membrane in human thyroid diseases: an immunohistochemical study of type IV collagen, laminin and heparan sulphate proteoglycan.

Basement membrane (BM) alteration in thyroid diseases was examined by immunohistochemistry using antibodies for the three major BM proteins: type IV collagen, laminin and heparan sulphate proteoglycan. Linear epithelial BMs surrounding follicles accompanied by vascular BMs forming loops, similar to those seen in the normal thyroid, were observed in Graves' disease and adenomatous goitre. Hashimoto's thyroiditis showed scant epithelial BMs as a result of follicle destruction. In follicular adenomas, development of epithelial BMs seemed to be related to follicle formation; well-developed epithelial BMs were frequently seen in normo- or large-follicular type, whereas trabecular or solid types revealed scant or poorly developed epithelial BMs. Lumpy accumulation of BM proteins was detected in hyalinizing trabecular adenomas. Papillary carcinomas revealed two different types of papillae; one type contained both epithelial and vascular BMs, and the other had only vascular BMs. Epithelial BMs in invasive areas of papillary carcinoma were distributed in an irregular, interrupted manner, and were completely absent in many foci. Anaplastic carcinomas showed scant or a total loss of epithelial BMs. These results suggest that alterations of BM in thyroid diseases clearly reflect their architectural variations, presumably in connection with their function and/or biological behaviour.

Basement Membrane↗
PubMed1993

Nature and significance of calcium oxalate crystals in normal human thyroid gland. A clinicopathological and immunohistochemical study.

To elucidate the significance and nature of calcium oxalate crystals in the thyroid, we studied these crystals clinicopathologically and immunohistochemically in 182 normal thyroids from patients autopsied within 5 h of death. Under polarized light, calcium oxalate crystals showed brilliant birefringence and were invariably found within the colloid. The crystals were found in 73.1% of all cases but were more prevalent and denser in older individuals, with the highest prevalence (85.2%) being observed in those over 70 years of age. No crystals were seen in those under 10 years of age. Although underlying diseases seemed to have little influence, post-mortem delay apparently affected the prevalence and density of occurrence since the crystals tended to disappear with hours after death. An immunohistochemical study using anti-thyroid hormone antibodies revealed that the crystals were within negatively or weakly stained colloid and were not common in strongly stained colloid. These findings support the hypothesis that the occurrence of calcium oxalate crystals in normal human thyroid is associated with a low functional state of the thyroid follicles.

Adolescent↗
PubMed1993

Birefringent (calcium oxalate) crystals in thyroid diseases. A clinicopathological study with possible implications for differential diagnosis.

To elucidate the nature and significance of calcium oxalate crystals in the pathologic thyroid, we used polarized light microscopy to review 357 thyroid lesions. Under polarized light, calcium oxalate crystals had brilliant birefringence, and they were invariably identified within the colloid of follicles. The highest prevalence of crystals (87.9%) was in nodular goiters; they were also found in 60.0% of follicular adenomas and 33.3% of follicular carcinomas. The prevalence of crystals in papillary carcinomas was very low (5.4%). Therefore, the overall prevalence was 69.4% in benign nodules and 7.6% in malignant nodules. A heavy deposit of crystals was seen only in benign nodules except for one case of follicular carcinoma. Graves' disease, focal thyroiditis, and subacute thyroiditis showed low prevalence: 25.0, 46.9, and 40.0%, respectively. In cases of toxic nodules, the crystals were sparsely identified within nodules, but abundantly observed in surrounding inactive tissues. Immunohistochemistry for thyroid hormones confirmed that the crystals tended to appear in inactive follicles. On tissue x-ray film, the crystals appeared as microcalcifications. As a result of these findings, we suggest that examinations of crystals are likely to be useful in the differential diagnosis of thyroid diseases and in possible estimations of the functional state of lesions.

Adenoma↗
PubMed1993

Serum collagenase-like peptidase activity correlated with bone mineral density. A study of 102 elderly women.

To clarify the relationship between collagenase-like peptidase (CL-peptidase) and bone metabolism, serum CL-peptidase activity and bone mineral density (BMD) in the lumbar spine, measured by dual energy X-ray absorptiometry (DEXA), were determined in 102 women with a mean age of 70 (41-94) years. The serum activity of CL-peptidase increased slightly with age up to the 8th decade, and then decreased. Next, we classified the subjects into the following 2 groups by age: a postmenopausal group 50-69 years, and an elderly group over 70 years. In the younger group serum CL-peptidase activity did not correlate with BMD, while in the elderly it did. Our result suggests that serum CL-peptidase activity may reflect bone resorption in elderly women.

Adult↗
PubMed1993

An investigation of the accuracy in measuring the body center of pressure in a standing posture with a force plate.

It has been reported that accuracy in the measured point of force application depends on the position and magnitude of load. The aim of this study is to investigate the error in measuring the body center of pressure in a standing posture with a force plate and to improve the accuracy by proposing a correction algorithm. The measurement of the point of force application with a calibrated load demonstrated its co-ordinates, which were scaled down towards the zero co-ordinate and moved parallel relative to the true co-ordinates. This trend was exaggerated with any decrease in magnitude of the load. The root mean square (r.m.s.) and maximum of errors at light load of 10 kg were 10 and 18 mm in the X axis, and 6 and 12 mm in the Y axis, respectively. The error seems to result from such causes as (i) non-linearity of the load cell, (ii) deformation of the top plate due to load application and (iii) differences in characteristics among individual load cells, including amplifiers. A mathematical representation of the measured point of force application accounting for these causes of error has been made and an algorithm for estimating the true point at any magnitude of load with only one correction equation is proposed. Actual correction of the measured point demonstrated an expected improvement in the r.m.s. error to less than 1 mm at any magnitude of load greater than 10 kg and the validity of this algorithm was confirmed.

Algorithms↗
PubMed1993

Surface adhesion and attachment factors in bone morphogenetic protein-induced chondrogenesis in vitro.

Bone morphogenetic protein (BMP) induces cartilage and bone development in embryonic and post-fetal life. Bone morphogenetic protein-induced chondrogenesis in outgrowths of muscle connective tissues on various furrowed and unfurrowed fibronectin-coated substrata was observed by biochemical and histologic methods. The substrata consisted of cellulose acetate membranes, atelocollagen, denatured autoclaved demineralized bone matrix, bone matrix deactivated by extraction of BMP with guanidine hydrochloride (GuHCl), and aggregates of insoluble BMP and associated noncollagenous proteins (BMP/NCP) prepared from bovine bone. The furrows, which were mechanically cut into the substrata, were intended to increase surface area and provide extra spaces for cell proliferation under compression. The extent to which extracellular attachments were required for induced cartilage development was reflected in the quantity of cartilage formed when BMP/NCP, either in insoluble or in water-soluble form, was introduced was greatest on GuHCl-extracted bone matrix. On cellulose acetate and atelocollagen, BMP-induced cartilage development was relatively scanty. A substratum of bone matrix, denatured by autoclaving at a minimum of 125 degrees, permitted cell-to-cell adhesion but not cell-to-substratum attachments; the end product was loose fibrous connective tissue only. In contrast, cartilage development occurred on surfaces of undissolved particles of BMP/NCP. Water-soluble human BMP induced development of masses of amorphous cartilage. Even after it was extracted with GuHCl, rat bone matrix may have retained trace amounts of endogenous BMP. Thus, when the requirements of cells for cell-to-cell adhesion and cell-to-substratum attachment, including mechanical factors such as furrows to enlarge surface area, were met, cartilage development was a manifestation of temporal, spatial, and BMP distribution patterns. In situ hybridization and immunofluorescent microscopy with the aid of antirecombinant BMP antibiotics may provide new information about morphogenesis.

Animals↗
PubMed1993

Microvascular and cellular defects of the periosteum of osteogenesis imperfecta.

Periosteum stripped from fragments of diaphyseal long bones from osteogenesis imperfecta (OI) patients was examined both in vivo and in vitro. The OI periosteum was thickened and characteristic finding was a defective microvascular system. The vascular walls of arterioles and capillaries were thick and the lumina of many of these vessels were narrowed or occluded by hypertrophic endothelial cells and multiplication of smooth muscle cell layers. Circulatory deficiency in the OI periosteum might be regarded as one of the causes of the slender, osteopenic diaphyseal bone characteristic of the disorder. A higher proliferative activity was observed in cultured OI periosteal cells, but the cytoplasmic structure showed increased myelinoid bodies and smooth endoplasmic reticulum and decreased lysosomes and rough endoplasmic reticulum. These findings may be related to the abnormal metabolic activity of OI periosteal cells.

Adolescent↗
PubMed1992

Multiple thyroid involvement (intraglandular metastasis) in papillary thyroid carcinoma. A clinicopathologic study of 105 consecutive patients.

Multiple thyroid involvement (MTI) in papillary thyroid carcinoma was clinicopathologically studied in 105 non-selected, consecutive patients. Whole thyroids resected by total thyroidectomy were sectioned at intervals of 2-3 mm (mean number of slices per gland, 19.2) and histologically reviewed. The intraglandular cancer foci, other than the tumor regarded as the primary focus, were demonstrated in 82 (78.1%) of 105 patients. The foci were usually small (less than 4 mm) and were not accompanied by sclerotic fibrous stroma or by a fibrous capsule. These small foci were distributed around the primary lesion and also were found frequently (61.0%) in the opposite lobe as bilateral disease. In the opposite lobe, a similar incidence (approximately 30%) of disease was obtained in each of the three parts (upper, middle, and lower). The mean number of foci in patients with MTI was statistically correlated to age, the presence of lymph node metastases, and the presence of solid areas or psammoma bodies in the primary tumor. It was concluded that MTI could be regarded as one of the most striking and important biologic characteristics of papillary thyroid carcinoma.

Adolescent↗
PubMed1991

Serum levels and thyroid tissue expression of CA50 and CA 19-9 in patients with thyroid tumor.

A 77-year-old man was admitted to the hospital with a thyroid nodule. The levels of serum tumor-associated carbohydrate antigens (CA 50, CA 19-9) and thyroglobulin (HTG) were markedly increased. We performed total thyroidectomy and right neck lymph node dissection. After treatment, the serum CA 50, CA 19-9 and HTG levels were markedly decreased. Histological examination of the thyroid tumor showed papillary adenocarcinoma and the dissected neck lymph nodes contained metastatic adenocarcinoma. The expression of CA 50 and CA 19-9 (defined by the monoclonal antibodies) was studied by immunoperoxidase staining from the normal and carcinomatous thyroid tissues and the dissected neck lymph node. CA 50 was expressed more strongly by the carcinoma cells than CA 19-9. The positive rates for serum CA 50 and CA 19-9 levels in other patients with papillary adenocarcinoma were not significantly higher compared with patients with benign nodules and normal subjects. But a significant positive correlation was found between the diameter of the carcinoma and the serum levels of CA 50 and CA 19-9. These results suggest that the serum levels of CA 50 and CA 19-9 might not become useful markers for diagnosing carcinoma of the thyroid, but might be useful markers for monitoring the growth or recurrence of papillary adenocarcinoma of the thyroid in patients with high serum levels of CA 50 and CA 19-9.

Adenocarcinoma, Papillary↗
PubMed1991

Zonal and age-related difference in the amounts of creatine kinase subunits in cartilage.

Energy metabolism in cartilage may affect the morphogenetic events of skeletal growth. Investigating enzymes responsible for energy metabolism in cartilage, such as creatine kinase (CK), can provide clues to an understanding of pathogenesis and treatment of osteochondrodysplasias. In this study levels of CK subunits M (muscle type) and B (brain type) were measured by a highly sensitive enzyme immunoassay system in growth and resting cartilages of the rat rib at various ages. CK-M was predominant, but there was no statistically significant difference in its quantity of CK among cartilages of various ages or between resting and growth cartilage. In contrast, although CK-B levels were low, they showed a significant decrease with advancing age and a significant increase in growth cartilage as compared with resting cartilage. The results of this study suggest that CK in cartilage, especially CK-B, may play an important role in skeletal growth.

Aging↗
PubMed1990

Mucoepidermoid carcinoma of the thyroid gland.

An extremely rare case of mucoepidermoid carcinoma of the thyroid in a 56-year-old woman is presented. The patient clinically having Hashimoto's thyroiditis was noted a nodule in her neck. The tumor was sited in the midportion of the left lobe of the thyroid, and histologically it showed both squamous features and mucin production. The squamous cells were arranged in solid sheets with horny pearls and the mucous cells tended to line dilated duct-like elements. Ultrastructurally, the epidermoid cells had aggregates of tonofilaments and well-developed desmosomal attachments, and the mucous cells contained numerous mucin granules in their cytoplasm. Immunohistochemical studies revealed that cytokeratin antibodies showed positivity for both the lining cells and squamous cells, whereas carcinoembryonic antigen positivity was found in the lining cells and intraluminal material. The tumor cells were negative for thyroglobulin, calcitonin, vimentin, chromogranin, and neuron-specific enolase. These unusual histologic and immunohistochemical features are suggestive of a tumor related to the so-called "solid cell nest" of the thyroid.

Carcinoembryonic Antigen↗
PubMed1990

[Immunohistochemical studies of collagen types I, III and IV distribution and the expression of procollagen III peptide in papillary carcinomas of the thyroid].

Collagen types I, III and IV and procollagen III peptide (P III P) were examined immunohistochemically in 38 papillary carcinomas of the thyroid. The immunoreactivity to both type I and type III collagen was diffuse and abundantly observed in the fibrous stroma, where it displayed a fibrillar and/or granular pattern with little difference in the intensity of the staining. The immunoreactivity to collagen type IV was localized in the basement membrane of the vessels and partly in the tumor cell nests. A distinctive cytoplasmic immunoreactivity to P III P was observed in the cancer cells and the fibroblasts in all of the 38 papillary carcinomas, specifically an intense and extensive immunoreactivity by the cancer cells present in tumors having fibrosclerosing stroma and/or showing an extensive local invasion. Thus, it is conceivable that stromal collagen in a papillary carcinoma can be produced by not only the fibroblasts but also by tumor cells and its productivity could be affected by the degree of the tumoral invasion.

Carcinoma, Papillary↗
PubMed1989

Malacoplakia of the thyroid gland.

A case of malacoplakia of the thyroid gland is described in a 50-year-old Japanese woman. This lesion clinically mimicked a malignant neoplasm, and the true diagnosis of malacoplakia was made only after histologic examination; light microscopy revealed a granulomatous nodule with an accumulation of von Hansemann's histiocytes containing PAS-positive and von Kossa's-positive intracytoplasmic and extracytoplasmic inclusions known as Michaelis-Gutmann bodies. There were some foci consisting of neoplasm-like or hyperplastic residual follicles within the lesion. Electron microscopically, a small number of bacilliform organisms were demonstrated within the lesion. X-ray microanalysis of Michaelis-Gutmann bodies was performed and revealed the presence of phosphorus, calcium, iron, and chloride. It is suggested that the malacoplakic lesion may be associated with the hyperplastic or neoplastic follicular lesion, and bacterial infection could be important in the causation of malacoplakia of the thyroid gland.

Female↗