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S Okada

Publications and source records attributed to S Okada.

At least 1,243 records · Page 69Linked to original sources
PubMed1984

Natural suppressor (NS) cells found in the spleen of neonatal mice and adult mice given total lymphoid irradiation (TLI) express the null surface phenotype.

We studied the surface markers of suppressor cells of the mixed leukocyte reaction (MLR) that are transiently present in the spleens of neonatal mice after birth and of adult mice after total lymphoid irradiation (TLI). Approximately 80% of the mononuclear cells in the spleen, within the first few days after birth or after TLI, express neither the Thy-1 antigen nor surface immunoglobulin (Ig). After 30 days, less than 20% of mononuclear cells bear this null phenotype. With the use of the panning technique, we showed that the suppressors of the MLR are confined to the null cell population. The null suppressor cells are not macrophages because they did not carry macrophage markers identified by the monoclonal antibodies anti-MAC-1 and F4/80. In addition, the suppressor cells did not stain for nonspecific esterase and did not adhere firmly to plastic or glass. Spleen cells from TLI-treated mice maintained their suppressive capacity after culture in vitro for 6 to 8 wk. The cultured suppressor cells did not develop mature T cell, B cell, or macrophage markers during this time interval. Thus, the suppressor cells did not appear to be precursors of the latter cells. There was no clear relationship between the suppressor activity of the spleens and natural killer (NK) activity; the kinetics of these activities in newborn spleen appear to be inversely related. The suppressor cells, however, are similar to NK cells in that both are found in the absence of antigenic challenge, lack antigen specificity, and bear the null surface phenotype. Thus, we have termed the former cells natural suppressor (NS) cells.

Aging↗
PubMed1984

In vitro propagation and cloning of murine natural suppressor (NS) cells.

During a short period of time after birth or after radiotherapy, the spleens of neonatal and adult TLI-treated mice contain suppressor cells of the mixed leukocyte reaction (MLR) and of graft-vs-host disease. The present report shows that the MLR suppressive activity of spleen cells from TLI-treated adult BALB/c mice can be maintained in long-term tissue culture by using conditioned medium. The suppressor cells can be cloned by limiting dilution, and reproducibly inhibit the [3H]TdR incorporation in the MLR at responder-to-suppressor cell ratios of 50:1. There is no antigen specificity or H-2 haplo-type restriction of the MLR suppression. The suppressor cells do not inhibit [3H]TdR per se, because no inhibition was observed in co-culture experiments with the EL4 tumor line or the IL 2-dependent HT-2 cell line. By using immunofluorescent staining techniques, the surface phenotype of the suppressor cells was found to be similar to that reported previously for cloned NK cells (Thy-1+, Lyt-1-, Lyt-2-, Ig-, Ia-, MAC-1-, asialo-GM1+). However, the suppressor lines showed no natural killer activity when YAC-1 target cells were used. Thus, the suppressor lines have been termed "natural suppressor" cells to indicate surface marker similarities to NK cells, both in vivo and in vitro, but different effector functions.

Animals↗
PubMed1984

Ultrastructural features of macrophages of armadillos infected with actively multiplying Mycobacterium leprae.

Experimental leprosy lesions in the armadillo (Dasypus novemcinctus) were studied by freeze etching and ultrathin sectioning. Infected macrophages have distinct intracytoplasmic foamy structures in the form of spherical droplets accumulated around multiplying bacilli. This finding is the same as those observed in human lepra cells and nude mice macrophages infected with M. leprae.

Animals↗
PubMed1984

[Ultrastructural and pathological studies of chondromyxoid fibroma of bone].

Histological and electron microscopic studies were carried out on a chondromyxoid fibroma in the right femur of a 8 years old boy. Although chondromyxoid fibroma contained chondroid, fibrovascular and myxoid components, the chondroid zone was transformed into myxoid zone through degeneration of chondroblastic tumor cells. Fibroblastic tumor cells gave no findings specific for fibroblast and fibrocyte on electron microscopy. Most primitive tumor cells were found in the fibromatoid zone. These cells have probably differenciated to fibroblastic and chondroblastic tumor cells. Histiocytes were gathered around the blood vessel. Despite the native of chondromyxoid fibroma as one of the bone tumor of cartilagenous deviation, it showed the characteristics of histiocytic tumors in part.

Cell Transformation, Neoplastic↗
PubMed1984

[Tuberculosis of the penis: report of a case].

Tuberculosis of the penis has become a rare disease since antituberculosis drugs have come to be widely used. It may be primary or secondary to coexisting tuberculosis elsewhere in the body. In the case of gross destruction of the glans penis and urethra, it is not always easy to differentiate tuberculosis from carcinoma of the penis. A 87-year-old man was admitted with painful ulceration on the glans penis and dysuria. Physical examination strongly suggested carcinoma of the penis other than infectious diseases. In addition, there was no evidence of a tuberculous lesion in other urogenital organs or lungs. Therefore, partial amputation of the penis was performed after admission to the hospital. Histopathological findings, however, revealed typical tuberculosis with Langhans' type of giant cells and no malignancy.

Aged↗
PubMed1984

[Clinical value of testicular lymphangiography in diagnosis of retroperitoneal metastases].

Testicular lymphangiography was performed before retroperitoneal lymph node dissection in 20 patients with testicular tumor. The clinical value of testicular lymphangiography in the diagnosis of retroperitoneal metastases was evaluated retrospectively in comparison with the findings obtained by retroperitoneal lymph node dissection. In 12 patients who had no metastasis in the primary lymph nodes of the testis, testicular lymphangiography showed the lymph vessels to be diverged into 2 to 6 vessels (mean: 3.5) at the level between L2 and L4, and 4 to 10 lymph nodes (mean: 6.2) at the level between L1 and L4 were filled with contrast medium. On the other hand, in 8 patients who had metastases in the primary lymph nodes, several abnormal findings were observed in both lymph vessels and nodes, i.e., discontinuity, extravasation of contrast medium, dilatation, displacement and reflux to the distal side in the lymph vessels, and decrease in number (less than 2), non-visualization, filling defect, displacement and contrastfilling in the contralateral side in lymph nodes. Three to 5 of these abnormal findings were usually found in each case. The extravasation of contrast medium was not a finding specific to cases with lymph node metastases, because it was also found in a few cases without metastases. Testicular lymphangiography is a valuable method to detect primary lymph node metastases from testicular tumor. However, the combination of testicular and foot lymphangiography is imperative to demonstrate wide spread lymph node involvement in the retroperitoneum.

Humans↗
PubMed1984

Dental survey in Nigeria. Part I. Prevalence of dental caries in Nigeria.

A joint dental epidemiological survey was carried out in 1981 in the ancient city of Ile-Ife and its environs in the Federal Republic of Nigeria. The survey was made with the University of Ife, Ile-Ife, Oyo State, Nigeria, as the base. The occurrence of caries in 898 Nigerian school children of 509 urban and 389 rural children was compared with the occurrence of caries in the Japanese children. The results showed that the incidence of caries in the Nigerian school children was much lower than that of their Japanese counterpart. However, it is projected that with the increase in the consumption of sweet drinks and food in Nigeria, if superimposed on the existing poor oral hygiene, the incidence of caries will increase greatly.

Adolescent↗