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M Tokashiki

Publications and source records attributed to M Tokashiki.

7 recordsLinked to original sources
PubMed1999

The validity and significance of substage IIIC by node involvement in epithelial ovarian cancer: impact of nodal metastasis on patient survival.

OBJECTIVE: The aim of this study was to examine whether there is a possible difference in patient survival (1) between node-positive and node-negative groups for Stage I, II, IIIA+B, and IIIC disease and (2) between node-positive Stage I through IIIB disease and Stage IIIC disease. METHODS: Medical records of 125 patients with Stage I, II, and III epithelial ovarian cancer were retrospectively analyzed for clinical and histological characteristics with special reference to node-positive or -negative status, and patient survival by lymph node status was compared for FIGO intraperitoneal stage. RESULTS: One hundred eleven of 125 patients were explored for retroperitoneal and inguinal nodes and divided into a node-positive group [n = 35 (31.5%)] and a node-negative group [n = 76 (68.5%)]. Stage III disease and histological grade 3 disease were significantly more frequent in the node-positive group in comparison with the corresponding figures in the node-negative group (P = 0.0007 and P = 0.0005). The 10-year survival was not significantly different between the node-positive and the node-negative group for each of Stage I, II, IIIA+B, and IIIC disease. However, survival was considerably worse in the node-positive group compared to that in the node-negative group for each of Stage I and II disease, and was significantly worse for Stage I+II disease (P = 0.0172). The survival was significantly worse in the node-positive group compared to that in the node-negative group also for Stage I through IIIB disease taken as a whole (P = 0.0212), although not for Stage IIIA+B disease alone. On the other hand, patient survival of node-positive Stage I through IIIB disease, taken as a whole, was significantly better than that in Stage IIIC disease (P < 0.0001). CONCLUSIONS: It might not be valid, on the basis of patient prognosis, to group node-positive Stage I, II, and IIIA+B disease into a criterion of Substage IIIC together with Stage III disease of abdominal implants greater than 2 cm in diameter outside the pelvis. For further evaluation of the prognostic significance of node involvement, survivals should be compared among patients with de novo node disease, with node disease removed, and otherwise similar patients without node disease, ideally in a prospective randomized trial with a large number of patients.

Adult↗
PubMed1996

Large-scale perfusion culture process for suspended mammalian cells that uses a centrifuge with multiple settling zones.

A high-cell-density perfusion culture process, using a novel centrifuge, was developed. The centrifuge has spiral multiple settling zones to separate cells from culture medium. Because of the multiple zones, the separation area can be efficiently increased without enlarging the diameter of the centrifuge. The centrifuge used in this study had a separation capacity of 2600 ml culture medium min -1 at 100 g of the centrifugal force. A new cell separation and withdrawal method was also developed. The cells separated in the centrifuge can be withdrawn easily from the centrifuge with no cell clogging by feeding a liquid carrier such as a perfluorocarbon into the centrifuge and pushing the cells out with the liquid carrier. By this culture process, monoclonal antibodies were produced with mouse-human hybridoma X87X at a cell density of about 8 x 10(6) cells ml -1 for 25 days. This centrifuge culture shows promise as a large-scale perfusion culture process. (Himmelfarb et al. 1969; Feder and Tolbert 1983) usually have the problem of filter clogging, and perfusion culture processes with gravitational cell settling (Tokashiki and Arai 1989) are limited in scale-up because of low separation efficiency. Recently centrifugal separation of cells from culture medium has been used for perfusion culture processes (Hamamoto et al. 1989; Tokashiki et al. 1990; Apelman 1992; Jäger 1992). This process essentially has a high separation efficiency and can avoid further operational problems, such as filter clogging, by the type of filtration. To investigate the scale-up feasibility of the centrifuge culture system, we have developed a new type of centrifuge with four layers of spiral cell-settling zones to increase the separation area, and a novel cell separation and withdrawal method using a perfluorocarbon.

Animals↗
PubMed1993

Perfusion culture apparatus for suspended mammalian cells.

A variety of processes have been proposed for mammalian cell culture in the commercial production of useful substances (e.g., monoclonal antibodies, therapeutic and diagnostic proteins). Among them, the perfusion culture of suspended non-immobilized cells is the most advantageous. Perfusion culture can be classified by the separation process of suspended cells from the culture mixture into three types, namely filtration, gravitational settling and centrifugation. From a commercial point of view, the present situation and technical problems of suspended cell perfusion culture will be reviewed based on the three types. The recent development of perfusion culture has been carried out mainly on the filtration separation process, but the centrifugation process seems to have a promising future because of operation stability and scale-up feasibility. The reasons will be explained in details.

Animals↗
PubMed1992

Transferrin recycling perfusion culture of hybridoma cells.

A perfusion culture of hybridoma cells in serum-free medium recycling transferrin was carried out, which greatly reduced the level of transferrin that was needed. The culture was maintained even without supplying transferrin for nine days. IgG concentration reached 1.1 mg ml-1 in a month of recycling and its ratio to the total protein was 45.8%. The affinity of the antibody did not decrease and no degradation was observed after long recycling period. The cell density under recycling condition was 2-3 times higher than that without recycling. It was indicated that there was autocrine growth promoting activity in the culture supernatant.

Animals↗
PubMed1991

Diagnostic hand anomalies in Smith-Magenis syndrome: four new patients with del (17)(p11.2p11.2)

We report clinical and cytogenetic findings of 4 children (2 boys and 2 girls) with the Smith-Magenis syndrome. All 4 patients had an interstitial deletion of 17p: del(17) (p11.2p11.2). Their clinical manifestations included brachycephaly, midface hypoplasia, prognathism, upper lip eversion, short and broad hands with short fingers, clinodactyly of the fifth fingers, fingertip pads, moderate mental retardation, and behavior problems. Analysis of the metacarpophalangeal pattern profiles in patient 2 showed progressive shortness from the metacarpals to the proximal, middle, and the distal phalanges. The fingerpads observed in all 4 patients have hitherto been noted in only one of 26 previously reported patients with the syndrome. These findings serve as a useful clue to the diagnosis of the syndrome.

Abnormalities, Multiple↗
PubMed1990

High density culture of hybridoma cells using a perfusion culture vessel with an external centrifuge.

The influence of centrifugal force on the growth of cells was examined by exposing the cells of the mouse-human hybridoma X87 line to centrifugal force (100-500 G) for ten minutes twice a day and comparing the static culture with that of unexposed cells. In this experiment, both cell proliferation and specific antibody productivity were independent of the centrifugal effect, and gave the same results as in the case of no exposure to centrifugal force. High density cultivation of the mouse-human hybridoma X87 line was obtained by a perfusion system where the cells were separated from the culture medium by continuous centrifugation. In the serum-free culture, the maximum viable cell density exceeded 10(7) cells/ml, and monoclonal antibody was stably produced for 37 days. The results in this culture were equivalent to those obtained by intermittent centrifugal cell separation from the culture medium, and separation by gravitational settlement.

Animals↗