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We investigated the various conditions necessary for potentiating the immunogenicity of viable Friend virus (FV)-infected rat fibrosarcoma KMT-17 cells. The immunogenicity was most potent among cells passaged through three generations of FV-tolerant rats; a single subcutaneous immunization induced an increase in the transplantation resistance (LTD50) of 10,000 or more. It was also found that intradermal immunization of the tumor cells induced stable and potent resistance to the transplantation of non-xenogenized tumor cells soon after immunization, and that irradiated non-xenogenized tumor cells were effective in supplying booster immunization. Active immunotherapy against KMT-17 cells pre-transplanted subcutaneously was carried out on the basis of the above findings with the results that the active anti-tumor immunization alone caused a complete regression in 30% of the tumor-burdened rats. These findings indicate the possibility of achieving active immunotherapy with xenogenized tumor cells.

Magnetic resonance (MR) images were obtained from 171 patients with benign and malignant neoplasms in the uterus and ovary, by using a low magnetic-field machine with 0.22 T, and its usefulness is discussed. Small uterine neoplasms (a few mm of its diameter) can be detected as an abnormal intensity. Therefore, the detectability is helpful for determination of their staging. In addition, some adenomyosis can also detected as distinctive findings, although it is difficult to point out those diseases by other imaging modalities. From MR images of ovarian cystic tumor, the biochemical information of its fluid content can be obtained. However, it is difficult to get distinctive features from MR images of solid neoplasms. Even though the magnetic field is low such as 0.22 T, MR images are useful for diagnosis of gynecological neoplasms because of the high contrast image quality and the capability of providing tomograms with arbitrary planes.

Chloroquine increased the binding of 125I-labeled insulin to rat hepatoma cells (R-Y121B) at 4 degrees C. The effect of chloroquine on insulin binding was amplified at 23 degrees C, and a large increase in cell-associated radioactivity was observed. Scatchard analysis showed that chloroquine increased the affinity of insulin for cells at both 4 degrees C and 23 degrees C, and that this increase eventually caused the accumulation of insulin internalized by cells at 23 degrees C.

The effects of dietary vitamin B-2 and vitamin E on delta9-desaturation of stearoyl-CoA, catalase, glutathione peroxidase, superoxide dismutase and electron transport components in rat liver microsomes have been investigated. delta9-desaturase activities were decreased on diets deficient of vitamin B-2, E and supplemented with E. Among the peroxide-scavenging enzymes, only the catalase activity in microsomes correlates significantly with delta9-desaturase activity. In vitro addition of bovine catalase had no effect on microsomal delta9-desaturase activity on control diet. However, it enhanced the delta9-desaturation in microsomes on vitamin B-2-deficient diet which contained low catalase and high superoxide dismutase activities, compared to those in microsomes of control diet. It is suggested that the hydrogen peroxide-generating and -decomposing systems may play an important role on the delta9-desaturase activity in microsomes.

It is already known that immunization with viable tumor cells which had been artificially infected with Friend virus (xenogenized tumor cells), one of murine leukemia viruses, produced a strong anti-tumor immunity against the identical non-infected tumor in comparison with that with mitomycin C-treated or irradiated non-infected tumor cells. Lethal tumor dose which could kill 50% of rats (LTD50) was increased up to 1,000 times by the immunization with the viable xenogenized tumor cells. In this presentation, procedure how to augment immunogenicity of the xenogenized tumor cells was examined. Intradermal single immunization with the xenogenized tumor cells (third passage generation through Friend virus-tolerant rats) inhibited most strongly the subcutaneous growth of non-xenogenized tumor; LTD50 was markedly increased more than 10,000 times. In addition, the intradermal active immunization with the viable xenogenized tumor cells followed by the irradiated non-xenogenized tumor cells resulted in 30.8% of complete regression of the tumor subcutaneously transplanted.