Sodium butyrate is a four-carbon fatty acid and natural component of the colonic milieu. Butyrate has been shown to induce apoptosis in numerous types of cancer cells, and received much attention as a potential chemopreventive agent for colorectal cancer. However, during initial clinical trials, its efficacy was limited. X-irradiation or hyperthermia as an adjuvant significantly enhanced the cell growth arrest, alteration of the cell cycle, and cell death caused by butyrate. The balance between anti-apoptotic and pro-apoptotic Bcl-2 family proteins was lost and a mitochondrial pathway was activated. In this review, the interactions of butyrate with X-irradiation and hyperthermia are discussed.

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To improve the efficacy of hyperthermia treatment, a novel method of noninvasive measurement of body temperature change is proposed. The proposed technology, thermometry, is based on changes in the electromagnetic field distribution inside the heating applicator with temperature changes and the temperature dependence of the dielectric constant. In addition, an image of the temperature change distribution inside a body is reconstructed by applying a computed tomography (CT) algorithm. The proposed thermometry method can serve as a possible noninvasive method to monitor the temperature change distribution inside the body without the use of enormous thermometers such as in the case of magnetic resonance imaging (MRI). Furthermore, this temperature monitoring method can be easily combined with a heating applicator based on a cavity resonator, and the novel integrated treatment system can possibly be used to treat cancer effectively while noninvasively monitoring the heating effect. In this paper, the phase change distributions of the electromagnetic field with temperature changes are simulated by numerical analysis using the finite difference time domain (FDTD) method. Moreover, to estimate the phase change distributions inside a target body, the phase change distributions with temperature changes are reconstructed by a filtered back-projection. In addition, the reconstruction accuracy of the converted temperature change distribution from the phase change is evaluated

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This paper describes a new system to match the impedance automatically for a re-entrant resonant cavity applicator during brain tumor hyperthermia treatments non-invasively. We have already discussed the effectiveness of the heating method using a manual impedance matching controller with heating experiments of an agar phantom and computer simulations. With this heating method, to generate heating power in the cavity, it is necessary to match the impedance and to tune the resonant frequency. In the initial prototype heating system, both were manually adjusted. However, it was difficult to match the impedance and to tune the frequency especially using a high resonant frequency.
To overcome this problem, we developed the automatic impedance matching system (AIMS). It is known that reflected power is generated when the impedance matching is not complete. In this system, to reduce the reflected power which is fed back to the computer, the stepping motor to turn the dial of the variable capacitors is controlled by developed software. To evaluate the developed AIMS, the heating experiments of the agar phantom, using several electromagnetic modes, were performed. The VSWRs are 1.05 and 1.01 using manual matching and AIMS, respectively. From these results, we found that the temperature rise in the agar phantom using AIMS was about 180% (with TM₀₁₂-like mode) and about 110% (with TM₀₁₀-like mode) more than using the manual type controller under the same heating condition. It was found that the proposed system was very effective for hyperthermia treatment using the resonant cavity applicator even when the resonant frequency was high.

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