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Biomedical subjects

S Komiya

Publications and source records attributed to S Komiya.

81 records · Page 5Linked to original sources
PubMed1984

An ultrastructural study of extraskeletal Ewing's sarcoma.

A case of extraskeletal Ewing's sarcoma was studied ultrastructurally, cytologically, and cytochemically. This tumor was, as in that of osseous origin, composed of densely packed highly undifferentiated blastemic cells and so-called "darker cells." The principal tumor cells were undifferentiated cells, which were characterized by the scant cytoplasm containing a variable amount of glycogen granules, large round or oval nuclei with dispersed chromatin, and rudimentary cytoplasmic junctional complexes. Some of the darker cells seemed to show somewhat histiocytic differentiation from principal blastemic cells, but the others were degenerating. Cytochemically, no tumor cells revealed the presence of peroxidase, lysozymes, and Factor VIII-related antigen. It is likely that both Ewing's sarcomas of osseous and extraosseous origin are defined as undifferentiated sarcoma merely characterized by the presence of glycogen.

Adolescent↗
PubMed1982

Asplenia and polysplenia syndrome.

This report described the morphological characteristics of seven cases of asplenia syndrome and three of polysplenia syndrome. Each syndrome has been characterized by a tendency for symmetric development of normally asymmetric organs, with varying degrees of cardiovascular anomalies. These latter anomalies are usually present in asplenia syndrome to a greater extent than in polysplenia syndrome. While, as observed in our material, the conotruncal anomalies were present more commonly in cases with asplenia, and absence of inferior vena cava with azygos continuation was seen specifically in all the cases with polysplenia. This evidence implied the presence of some pathogenetic distinction between the two syndromes.

Abnormalities, Multiple↗
PubMed1982

Electron microscopy of bone tumors--osteosarcoma, chondrosarcoma, giant cell tumor of bone.

Six cases of osteosarcoma, 5 cases of chondrosarcoma, and 6 cases of giant cell tumor of bone were studied by electron microscopy. The cells comprising osteosarcoma were basically osteoblasts and in addition to them, malignant chondrocytes, myofibroblasts and undifferentiated cells. The ratio of number of these cells were variable according to the portions designated microscopically as osteoblastic, chondroblastic and fibroblastic. Previous ultrastructural studies on osteosarcoma have scarcely revealed the presence of myofibroblasts. It is likely that osteosarcoma arises from undifferentiated mesenchymal cells capable of differentiating into various cells such as osteoblasts, chondroblasts, and fibroblasts; especially capable of differentiating into osteoblasts. On the other hand, chondrosarcoma was composed of the cells in the series of maturation from undifferentiated cells to chondrocytes. In high-grade malignant cases, glycogen particles and rough endoplasmic reticulum became less conspicuous, and occasionally malignant multinucleated cells were seen. In one case, endoplasmic reticular inclusions which were thought to be viral nucleocapsid by some authors were found. They, however, seemed to be formed by condensation of intracisternal granular material secreted by the rough endoplasmic reticulum. The cells comprising giant cell tumor of bone were multinucleated giant cells and stromal cells classified into four types. In a malignant case, giant cells showed no remarkable morphological change while stromal cells underwent an atypical change. This finding suggests that the mononuclear stromal cells are the principal tumor cells and the establishment of histological grading should mainly depend on the atypism of stromal cells. The tumor is likely to originate from undifferentiated mesenchymal cells which have the tendency of histiocytic and fibroblastic differentiation. The morphogenesis of multinucleated giant cells is not clarified in this study. Although the possibility that stromal cells are the origin of giant cells is still remained, it could also be speculated that giant cells are somehow related to immune response to the tumor having macrophage-related origin.

Adolescent↗
PubMedDate not supplied

LY309887, antifolate via the folate receptor suppresses murine type II collagen-induced arthritis.

OBJECTIVE: To examine the effect of LY309887, an inhibitor of glycinamide ribonucleotide formyltransferase in de novo purine biosynthesis on murine type collagen-induced arthritis (CIA). METHODS: CIA was induced by immunization with bovine type II collagen in adjuvant. The expression of folate receptors was examined in dissected synovial tissues and bone marrow cells from arthritic and non-arthritic mice by the semi-quantitative reverse transcription-polymerase chain reaction. LY309887 was administered to CIA mice after the onset of arthritis. Mice were monitored for arthritis index for 21 days. Levels of IgG1 and IgG2a antibodies against bovine type II collagen were measured in sera from CIA mice with or without LY309887 treatment by the enzyme-linked immunosorbent assay. Histologic analyse were also performed in synovial tissues from arthritic joints with or without LY309887 treatment. RESULTS: Levels of mRNA of folate receptor beta (FR-beta) were elevated in arthritic joints from CIA mice, compared with those in nonarthritic joints. The expression of mRNA of FR-beta was dominant in bone marrow cells of CIA mice. The administration of LY309887 suppressed the disease progression of CIA mice as defined by the lower arthritis index, and decreased production of serum IgG1 and IgG2a anti-type II collagen antibody, and the damage to cartilage or bone. CONCLUSION: The administration of LY309887 was effective on CIA mice. It was suggested that LY309887 might be useful in the treatment of rheumatoid arthritis.

Animals↗
PubMedDate not supplied

Aggressive bone tumorous lesion in infancy: osteofibrous dysplasia of the tibia and fibula.

The clinical experiences of 10 patients with osteofibrous dysplasia were reviewed. Mean age of the patients was 7.3 years; all had an intracortical, eccentric lesion in the anterior aspect of the shaft of the tibia. Seven of the patients underwent either an excision or an en bloc resection; the lesion recurred in four of the seven, and one showed pseudarthrosis. Surgical outcomes were unsatisfactory, especially in the younger patients. In contrast, the remaining three patients who did not undergo surgery showed satisfactory results. Nonsurgical treatment is generally recommended except in cases in which impending deformities seem certain. Osteofibrous dysplasia was characterized histologically by osteoid rimmed by osteoblasts, sinusoid surrounding osteoid, many osteoclasts in the sinusoid, and fibrous stroma. Ultrastructurally, stroma cells revealed the characteristics of preosteoblasts. Osteogenic potentiality was well-documented. This tumorous condition is likely attributed to dysremodelling, in which osteoclastosis is dominant to osteogenesis. Abnormal blood circulation in the periosteum is the likely pathogenesis of osteofibrous dysplasia.

Adolescent↗