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S Tatezaki

Publications and source records attributed to S Tatezaki.

26 records · Page 2Linked to original sources

Isolation and characterization of low- and high-metastatic clones from murine RCT (Radiological, Chiba, and Toyama) sarcoma.

We have established low- and high-metastatic clones, named RCT(-) and RCT(+) cells, respectively, from the RCT (Radiological, Chiba, and Toyama) sarcoma spontaneously developed in a C3H/He male mouse by the limiting-dilution method in vitro or by the combination of the lung passages and limiting-dilution methods. After 20 serial passages in vitro, the metastatic potential of each clone did not alter. Morphologically, both cells were spindle-shaped, but RCT(+) cells were slightly thicker and larger than RCT(-) cells. The organization of actin-containing filaments was slightly poorer in RCT(+) cells than that in RCT(-) cells. Marked differences were observed in their growth characteristics and adhesiveness to plastic or collagen-coated surfaces, that is, RCT(+) cells grew more slowly but could adhere more rapidly and firmly to the surfaces than RCT(-) cells. RCT(+) cells were agglutinated by all lectins used but several lectins could not agglutinate RCT(-) cells. These results could be a reflection of the difference in oligosaccharide residues on the surface of each cell and, in part, might reflect the difference in organization of the actin-containing filaments that regulate the mobility of lectin receptors. No significant difference between these cell clones was noted in their sensitivity to natural-killer-cell-mediated cytotoxicity in vitro. RCT(-) and RCT(+) cells are considered to be the most useful experimental model for the study of the certain sarcomas.

Animals↗

[Characteristics of high- and low-metastatic clones isolated from murine undifferentiated sarcoma (RCT sarcoma)].

We have established low- and high-metastatic clones from the undifferentiated RCT (Radiological Science-Chiba Cancer Center-Toyama Medical and Pharmaceutical University) sarcoma spontaneously developed in a C3H/He male mouse. Metastatic lesions of RCT sarcoma at the lung were inoculated into the subcutaneous tissue which was then cultured and cloned. Clones potential of low- and high-metastatic were named RCT(-) and RCT(+), respectively. RCT(-) cells were cloned by the limiting dilution method in vitro and RCT(+) cells were cloned by the combination of lung passages and limiting dilution methods. After 20 serial passages in vitro, the metastatic potential of each clone remained unchanged. Significant differences were noted in their growing property and adhesiveness to plastic or collagen-coated surfaces; RCT(+) cells grew more slowly, adhered more rapidly and firmly to the surfaces than those of RCT(-) cells. RCT(+) cells were agglutinated by all types of lectins used in this study, while several types of lectins could not agglutinate RCT(-) cells. These results would indicate that there was the difference in oligosaccharide residues on the surface of each cell. No significant difference between these cell clones in their sensitivity to natural killer cell-mediated cytotoxicity in vitro. We believe that RCT(-) and RCT(+) cells are very useful experimental model to study the mechanism of sarcoma metastasis.

Animals↗

[Diagnosis of malignant bone and soft part tumors].

In most bone tumors, the patient's local symptoms, which are usually pain and/or swelling, are nonspecific. Laboratory studies are of little significance in the diagnosis of the bone tumors, except myeloma and metastatic prostatic carcinoma. Though a definitive diagnosis must be made histologically, roentgenograms afford practically conclusive evidence of the malignant or benign nature of bony lesions and often indicate the histologic type. Differential diagnosis of malignant bone tumors which were misled as benign conditions were mainly described, and advantages and disadvantages of radiologic imaging methods such as RI, CT, and MRI, were also discussed. In the diagnosis of malignant soft part tumors, aspiration biopsy was strongly recommended but this necessitates experts' hand to avoid dissemination of the tumor cells to the normal tissue.

Adolescent↗

Systematic multi-modal treatment of osteosarcoma, with special reference to the role of fast neutron radiotherapy.

Sixty-one patients with osteosarcoma were treated. Twenty-four of these patients were managed with our systematic multi-modal treatment. Overall survival rate was markedly improved chiefly by intensive systemic chemotherapy with multiple drugs, especially adriamycin and high dose methotrexate. Preoperative regional intra-arterial infusion of anti-tumor drugs and fast neutron radiotherapy were employed and it was suggested that fast neutron had a higher relative biological effectiveness and a greater therapeutic gain factor as compared with X-rays. Fast neutron radiotherapy can play a significant role in the very systematic treatment of osteosarcoma and is specifically useful for preservation of the affected limbs.

Adolescent↗

Redundant nerve roots in patients with degenerative lumbar spinal stenosis.

Extensive fundamental and clinical investigations have been performed concerning redundant nerve roots (RNR) and the pathogenesis of cauda equina claudication (CEC) in degenerative lumbar canal stenosis (DLCS). These investigations consisted of (1) anatomic observations on RNR in 117 fixed cadaveric specimens, (2) myelographic study in 117 patients with or without DLCS, (3) operative observation on neural elements with special reference to the cauda equina in 56 DLCS patients (including a postoperative follow-up), and (4) electrophysiologic tests using spinal cord action potential recording under walking load preoperatively and intraoperative measurement of nerve conduction velocity of RNR. The RNR have neuronal losses resulting from a longer duration stenosis that suggests a sort of friction neuritis. Complicated factors contribute to the pathogenesis of CEC and the development of root gripping, such as the magnitude of RNR, the extent of the stenosis, a narrowed sac, age-dependent axial shortening of the spinal canal, and dynamic or postural factors. In cases with severe RNR, satisfactory operative results can be obtained only after thorough decompression with dural incision.

Action Potentials↗

Two cases of osteosarcoma occurring as second malignancy of childhood cancer.

We report on two patients in whom osteosarcoma occurred as second malignancy of childhood cancer. One patient had a malignant teratoma and the other adrenocortical carcinoma as the primary cancer. The emergence of cancer in cured cases and long-term survival cases of childhood cancer may result in an increase in the number of osteosarcomas seen in adolescence occurring as second malignancy. Anti-cancer drugs in large does were used for the treatment of a malignant teratoma in the former. These anti-cancer drugs may be involved in the occurrence of the second malignancy. In the latter, the patient has the germ-line mutation of p53 tumor suppressor gene, so genetic factors are presumably related to the occurrence of the second malignancy.

Adolescent↗

Knee rotation-plasty for malignant musculoskeletal tumors occurring around the knee joint.

BACKGROUND: In addition to the wide excision of malignant musculoskeletal tumor around the knee joint, surgical methods, such as total knee arthroplasty and knee rotation-plasty are available. Therefore, this study was undertaken to clarify the usefulness of knee rotation-plasty. MATERIALS AND METHODS: At the Chiba Cancer Center, knee rotation-plasty was performed in 27 patients with malignant musculoskeletal tumor around the knee joint. Patients were divided into two groups: Group S, in which operations were performed as salvage surgery (8 patients), and Group I, in which operations were performed as initial surgery (19 patients). The lower limb function was investigated in 17 patients (7 patients in Group S and 10 patients in Group I). The lower limb function was assessed by the Knee Evaluation System of International Symposium on Limb Salvage and the Knahr's assessment. RESULTS: Lower limb function in Group S measured an average of 25.7 points (85.6%), while the lower limb function in Group I measured an average of 23.6 points (78.7%). The majority of patients in both groups were capable of walking without a cane or doing light exercise with below-the-knee prosthesis, revealing good lower limb function. CONCLUSION: Whether it is performed as salvage or initial surgery, knee rotation-plasty can be useful method for reconstruction of the knee after wide excision of malignant musculoskeletal tumor around the knee joint.

Adolescent↗