A comparative anatomical study of the parasolitary nucleus (Kohnstamm & Wolfstein, 1907) using Weigert-Pal-Carmine or Nissle sections of mammalian brain-stem was made to discover its precise topography and cytoarchitecture. In transverse planes, the nucleus is usually found on the ventral side of the solitary tract. The parasolitary cells can be found not only among the solitary cells, but in the solitary tract, and in the parvocellular reticular formation (Fig. 1 a-f & 4). The oval or drop shaped parasolitary cells can be easily identified because they are nearly as large as the hypoglossal cells (Table 1). The cells of the solitary nucleus and parvocellular reticular formation are only one half to two thirds as large as the parasolitary cells. In sagittal planes, the mammalian parasolitary nucleus is one to four fifths as long as the hypoglossal nucleus. Its most developed part can be found somewhat oral to the obex (Fig. 1 h & 5). A Golgi study of the cat parasolitary nucleus was also made, using Golgi-Rapid and Golgi-Cox serial sections. Three-dimensional reconstruction with serial sections was attempted as far as possible. The dendrites of the cat parasolitary cells are thick and straight with blunted tips. They show only a few ramifications. The longest dendrite extends as far as 700 micrometers. The directions of the dendrites are variable. Each cell has eight to ten dendrites. Few spines can be observed (Fig. 2 a, b). The dendritic field of the parasolitary nucleus, as a whole, extends dorsally into the middle layer of th solitary nucleus, ventrally into the parvocellular reticular formation, medially into the intercalate nucleus, and laterally into the inferior nucleus of the vestibular nerve.

The experimental and clinical effects of bestatin were examined and the results obtained were as follows. Bestatin which is an immunomodulator discovered by Umezawa did not increase the bone marrow stem cells examined by the method of the spleen colony assay in the 60Co irradiated mouse. However, it prolonged the survival time slightly when it was administered 10-25mg/kg intraperitoneally. Clinically, bestatin was administered to the patients with gastrointestinal cancer. It did not influence on the PHA-induced lymphocyte blastformation rate, but it increased the peripheral lymphocyte count and PPD skin reaction in the cases of curative resection and increased the peripheral lymphocyte counts in the cases of nonresection after 1 month of the operation.

A histopathological study on an autopsy case of 38-year-old female who had suffered from huge glioma and received radiation therapy as well as operation and chemotherapy was reported. The tumor mainly involved the right frontal lobe and partially invaded to the left cerebral hemisphere. Subarachnoidal dissemination of tumor cells was noticed in cerebellum, brain stem and spinal cord. Under the microscope the tumor was mainly consisted of astrocytic tumor cells, while oligodendrocytic ones and those with anaplastic or bizarre nuclei were observed among them. Though ependymomatous appearance was partially seen, no true rosette was found. From these findings the tumor was histologically diagnosed as anaplastic glioma. Simultaneously, there was massive coagulative necrosis which was limited to the irradiated area in the tumor tissue and surely attributable to irradiation. In addition, proliferation of gemistocytic astrocytes which was independent of glioma itself was widely observed in the field of irradiation. Another remarkable finding was spongiform degeneration which was located in the subpial area of brain stem including degenerative products of myelin sheaths and axons with neither inflammatory changes not gliosis. In some papers it is suggested that such a lesion has something to do with irradiation or chemotherapy. But in our case this lesion was found in non-irradiated area and no intramedullary injection of chemical agents was performed. Further, the distribution of this lesion was for the most part restricted to the domain of the pontine cistern which had been huge owing to stagnant hemorrhagic fluid. Therefore, it is highly probable that this lesion was caused by the abnormal pia-glial barrier.

Human tumor stem cell assay is an in vitro colony-forming technique. Double soft agar layers are used for culture tumor cells and cell lethality is judged by the numbers of colony formation in this assay. Single-cell suspension made from various malignant materials in cancer patients is placed in culture after exposing to various anticancer agents for one hour and incubated for two weeks. Antitumor effects of various anticancer agents against individual patients are evaluated by % inhibition of colony formation. Of 57 tumor specimens 42 (74%) formed at least five colonies per plate (per 0.5 x 10(6) cells). The colony-forming rates of various malignancies are as follows: breast cancer 14/15 (93%), ovarian cancer 8/10 (80%), stomach cancer 5/13 (38%), sarcoma 4/5 (80%), lung cancer 1/4 (25%), colon cancer 3/3, each of pancreas cancer, leukemia and primary unknown adenocarcinoma 2/2, malignant lymphoma 1/1. The median plating efficiency (number of colonies/number of nucleated cells plated) is 0.02% (range: 0.001-0.3%). High correlation between human tumor stem cell assay results and response of an individual patient's tumor to chemotherapy is reported by Salmon and Von Hoff. Human tumor stem cell assay is useful tool for the high prediction of chemosensitivity response.