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Both cell-mediated and cytokine-mediated antitumor activities were induced in peripheral blood mononuclear cells (PBMC) in short-term culture with streptococcal preparation, OK-432. Kinetic analysis of OK-432-activated killer activity (OKAK) showed that it reached a plateau level much faster (by 48 h of culture) than that detected in PBMC stimulated with recombinant interleukin 2 (rIL-2) (lymphokine-activated killer: LAK). We also found that the tumor growth inhibitory factor (TGIF) activity was produced in the culture supernatant (CSN) of the OK-432-activated PBMC (OK-MC) and the activity synchronously increased with augmentation of OKAK activity. The TGIF activity was rarely found in the CSN of rIL-2-stimulated PBMC. The TGIF activity detected in CSN of OK-MC was further characterized as derived from a cytokine different from interferon gamma (IFN gamma), tumor necrosis factor (TNF), or lymphotoxin (LT) by a neutralization test using monoclonal antibodies to these cytokines. These 48-h-cultured-OK-MC were adoptively transferred (adoptive immunotherapy: AIT) into 19 head and neck cancer patients either alone or in combination with chemotherapy and/or radiation therapy, and their therapeutic effects were examined. AIT was performed by intra-arterial or intratumoral administration of OK-MC. There were no significant side effects observed in this treatment. In these patients, approximately 1-10 x 10(7) cells were transferred into the tumor burden. Of the 19 patients, 17 had primary cancer, and in 6 (6/17;35%) of them complete remission (CR) of the tumor was obtained. Partial remission (PR) was attained in 9 of the 17 patients (9/17; 53%), giving the overall response rate of 88%.(ABSTRACT TRUNCATED AT 250 WORDS)

Frozen-stored human spleen cells (SC) cultured with streptococcus preparation OK-432 acquired direct cytotoxicity to autologous as well as allogeneic tumor cells. The activated cells started to produce cytocidal cytokine TGIF, which is distinct from previously known cytokines. We examined the possibility of allogeneic adoptive immunotherapy (AIT) using these OK-432-stimulated spleen cells (OK-SC) in two cancer patients. Rapid necrosis of cancer tissue and remarkable decreases of tumor markers in tumor effusion were observed. There were no severe side effects.

The serum level of immunosuppressive substance (IS) was studied in 40 patients with primary oral cancer and in 79 patients without cancer. Its usefulness was evaluated as a parameter for monitoring therapy as well as recurrence of the tumors. Mean values for serum IS in patients with cancer and patients without were 687 +/- 284 micrograms/mL and 464 +/- 153 micrograms/mL, respectively. Normal healthy controls had a mean value of 431 +/- 105 micrograms/mL, with the cutoff value set at 641 micrograms/mL (mean +2 SD). Patients without cancer who had a severe infectious disease showed conspicuously high serum IS levels, and these values were closely correlated with their C-reactive protein values. The positive rate of IS increased in all patients with oral cancer was 58%. The mean level of serum IS in cancer patients was significantly higher than that of the controls (P less than .01), and the level was found to be more elevated as the stage of the disease advanced (stage I to III, 48%; stage IV, 68%). Histologic analysis of the tumor cells in patients with squamous cell carcinoma (SCC) showed that the mean serum IS level of those who had poorly differentiated SCC was much higher (937 +/- 181 micrograms/mL) than that of patients with well-differentiated SCC (616 +/- 159 micrograms/mL). Patients who had recurrent or metastatic cancer, or those who died from the cancer exhibited marked elevation of the serum IS levels, whereas patients who remained free of cancer in the follow-up period showed significantly lower serum IS levels. The rise and fall of the serum IS level was closely correlated with the disease progression and/or remission. These data strongly suggest that serum IS is a useful parameter for monitoring the disease stage as well as the effect of therapy on patients with oral cancer.

Scanning tunneling microscopy (STM) images of Pt ultrafine particles dispersed on silicon oxide and on aluminum oxide surfaces were obtained. The silicon oxide sample employed consists of a thin (ca. 0.6 nm thick) native silica film present on a Si(100) surface. The aluminum oxide sample was prepared by vacuum‐depositing aluminum metal on a native‐oxide‐covered single crystal silicon surface, followed by its air oxidation. Model Pt/SiO2 and Pt/Al2O3 catalysts were prepared by vacuum‐depositing Pt metal on those oxide surfaces. The STM observations of these sample surfaces were critically dependent on the tunneling conditions, and the optimum STM observation conditions for those supported metal catalyst systems were identified.

Scanning tunneling microscopy (STM) observations for “nonconductive” silicon oxide (silica) surfaces under ambient conditions were attempted. Thin (approximately 0.6 nm thick) silica films spontaneously formed on p- and n-type Si(100) surfaces were employed as silica samples. X-ray photoelectron spectra from these native-oxide-covered Si surfaces indicate that the valence band edges of the silica thin films are located at the binding energies of 3.0-3.3 eV. In the STM bias voltage dependence of the tip-sample distance on these surfaces under constant current, features attributable to conduction band edges of the silica films are observed at 2.5-3.5 eV above the Fermi edge. From these data it is conjectured that at the bias voltages beyond the range of approximately ±3.5 V, it may be possible to obtain the surface images of these thin silica films by means of STM. Silica surface images thus obtained was presented and discussed.

For the purpose to use bismuth films as strain gauges or strain transducers, about one hundred bismuth films were evaporated onto glass substrates in an ultra-high vacuum under various conditions, and their characteristics were measured. In carrying out measurements of the change in resistance with mechanical stress or strain (piezo- or elasto-resistance effect), the glass substrate was supported in the form of a cantilever and uniaxial stress was applied parallel to the film. The following characteristics were observed: The transverse elastoresistance is greater than the longitudinal effect; the gauge factor increases when the temperature is lowered; although relaxation phenomena exist in the elastoresistance in bismuth, they can be cancelled by means of the combination of both the transverse and longitudinal effects; inversion of the signs exists in such coefficients as the longitudinal gauge factor, Hall coefficient, and temperature coefficient of resistance at film thicknesses around 0.5∼1µ. Some further experimental investigations were carried out on films deposited on thin epoxy-resin substrates. They were used as surface strain gauges and showed a gauge factor of approximately 15 at room temperature, and no significant changes were observed under a long-run test of continuous vibrations of 106 repetitions with a strain of ±3.3×10-4. Response to an ultrasonic vibration of the frequency 20 kc/s was also found to be good. There is still a problem in determining the proper conditions for the production of the films as strain gauges.