Toshikatsu Okumura

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The present study was to determine how afferents from the substantia nigra pars reticulata (SNr) of the basal ganglia to the pedunculopontine tegmental nucleus (PPN) in the brainstem could contribute to the control of behavioral states. We used anesthetized and acutely decerebrated cats (n=22). Repetitive electrical stimulation (10-100 Hz, 20-50 microA, for(More)
BACKGROUND AND AIMS Although branch duct intraductal papillary-mucinous neoplasms (IPMNs) of the pancreas without mural nodules are frequently observed in asymptomatic subjects, the natural history of these lesions has never been studied. The aim of this study was to elucidate the natural history of branch duct IPMNs without mural nodules. METHODS(More)
Orexins are novel neuropeptides that are localized in neurons within the lateral hypothalamus and regulate feeding behavior. The lateral hypothalamus also plays an important role in the central regulation of gut function. We therefore hypothesized that orexins might be involved in the central control of gastric acid secretion. To address this question, we(More)
We investigated the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) and the role of PPARgamma in cell growth in human gastric cancer cells. Reverse transcription-polymerase chain reaction, Northern blot and Western blot analyses showed that a human gastric cancer cell line, MKN45, expressed PPARgamma mRNA and protein. Luciferase(More)
To identify predictive molecular markers for gemcitabine resistance, we investigated changes in the expression of four genes associated with gemcitabine transport and metabolism during the development of acquired gemcitabine resistance of pancreatic cancer cell lines. The expression levels of human equilibrative nucleoside transporter-1 (hENT1),(More)
A respiratory gating technique was developed for radiotherapy of tumors unable to remain stable due to respiration. Irradiation was started and stopped with a microwave oscillator of a linear accelerator controlled by gating signals at specific points in the respiratory cycle. This technique was tested in a phantom specially designed to simulate a patient(More)
PURPOSE To determine the utility of dynamic magnetic resonance (MR) imaging in evaluation of head and neck lesions. MATERIALS AND METHODS Dynamic MR imaging was performed in 79 head and neck lesions. Five types of time versus signal intensity curves were obtained: type A, curve peaks 0-30 seconds after administration of contrast material; type B, curve(More)
BACKGROUND Nitric oxide (NO) has diverse activities under physiological and pathophysiological conditions in many types of cells. In cultured hepatocytes, NO is produced by inducible NO synthase (iNOS) in response to interleukin (IL)-1beta. Cis-controlling elements and transcription factors which were involved in iNOS gene expression in hepatocytes have(More)
Recent study has indicated that cocaine-amphetamine-regulated transcript (CART) is an anorectic chemical in the brain. In the present study, we examined the hypothesis that CART may act in the central nervous system to alter gastric function. Food consumption, gastric acid secretion, and gastric emptying were measured after injection of CART into the(More)