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Oxygen (O(2)) is a prerequisite for cellular respiration in aerobic organisms but also elicits toxicity. To understand how animals cope with the ambivalent physiological nature of O(2), it is critical to elucidate the molecular mechanisms responsible for O(2) sensing. Here our systematic evaluation of transient receptor potential (TRP) cation channels using reactive disulfides with different redox potentials reveals the capability of TRPA1 to sense O(2). O(2) sensing is based upon disparate processes: whereas prolyl hydroxylases (PHDs) exert O(2)-dependent inhibition on TRPA1 activity in normoxia, direct O(2) action overrides the inhibition via the prominent sensitivity of TRPA1 to cysteine-mediated oxidation in hyperoxia. Unexpectedly, TRPA1 is activated through relief from the same PHD-mediated inhibition in hypoxia. In mice, disruption of the Trpa1 gene abolishes hyperoxia- and hypoxia-induced cationic currents in vagal and sensory neurons and thereby impedes enhancement of in vivo vagal discharges induced by hyperoxia and hypoxia. The results suggest a new O(2)-sensing mechanism mediated by TRPA1., 新たな生体内酸素センサー機構の発見. 京都大学プレスリリース. 2011-08-29.

AIM: The aim of this study was to investigate the role for vascular endothelial growth factor (VEGF) and its receptors, VEGFR-1 and -2, in the hyperplastic polyp (HP)- serrated adenoma (SA)-adenocarcinoma (AC) sequence of the colorectum.Methods: Thirty-six HPs, 33 SAs and 7 ACs (which contained HP and/or SA) were immunohistochemically examined for the expression of VEGF, VEGFR-1, and VEGFR-2.Results: VEGF protein was expressed in the cytoplasm of SA and AC tumor cells, and VEGFR-1 and VEGFR-2 were expressed both in the cytoplasm and on the membrane of these tumors, while there was faint or no expression of VEGF, VEGFR-1 and VEGFR-2 in HPs. Immunohistochemical staining revealed that 8.3% (3 of 36) HPs, 87.9% (29 of 33) SAs and 100% (7 of 7) ACs were positive for VEGF; 2.8% (1 of 36) HPs, 97.0% (32 of 33) SAs and 100% (7 of 7) ACs were positive for VEGFR-1; 16.7% (6 of 36) HPs, 100% (33 of 33) SAs and 100% (7 of 7) ACs were positive for VEGFR-2. The expression of VEGF, VEGFR-1 or VEGFR-2 was statistically correlated with the sequence of HP, SA and AC (P < 0.0001, respectively) Conclusion: Our results suggest that the VEGF pathway may play an important role in the HP-SA-AC sequence., Acta medica Nagasakiensia, 53(4), pp.85-88 ; 2009

There have been no studies of the expression of superoxide dismutase(SOD) at the mRNA and protein level in skin cancers. Northern blot analysis and enzyme-linked immunosorbent assay (ELISA) were performed in order to analyze the expression of Cu, Zn-SOD and Mn-SOD in basal cell carcinomas (BCC) and normal skin (NS). The expression of Mn-SOD mRNA and protein was significantly higher in BCC than in NS. The expression of Cu,Zn-SOD, however, was high in BCC at the mRNA level, but not at the protein level. These results suggest that an increase in the expression of Mn-SOD relates to the development of BCCs., Acta medica Nagasakiensia. 2000, 45(3-4), p.9-13

The prevalence of brown adipose tissue (BAT) in the periadrenal adipose tissue was studied in 20 autopsy cases of amyotrophic lateral sclerosis (ALS). In 19 of 20 cases, the periadrenal BAT in focal or diffuse distribution was observed. Histometry of BAT revealed average occupancy rates of 21.6% and 4.2% in ALS and age-matched control cases, respectively (p, 熱帯医学 Tropical medicine 36(2). p43-49, 1994

Hitokura Dam is the multi-purpose dam whose functions are flood control, domestic water supply and maintenance of river environment etc., is constructed in the Ina River in the Yodo River System. Hitokura Dam’s location is very close to the urban area and downstream of Hitokura Dam, there are Kawanishi City, Ikeda City, Amagasaki City and other cities. Due to the location, around 300,000 of people visit Hitokura Dam area every year to enjoy the rich environment around there. Under the circumstances, we have been implementing various measures to keep and improve the environment in the reservoir and downstream of the dam. We have been returning sedimentation in the reservoir to downstream of the dam by conducting flashing discharge (artificial small-scale floods) since April 2003 in order to improve the habitat in the downstream of the river. We also have been monitoring creatures in the river periodically to check the effectiveness of the flashing discharge. We have the meetings to exchange opinions with people in the neighborhood, environment NPOs, fishery cooperatives and residents’ associations about how to keep and improve the river environment on regular basis. We also release fry of Ayu fish into the Ina River together with local residents experimentally. During the spawning season (from early June to mid July), there were not enough river water for fish downstream of the dam. To solve this problem, we operate the water level higher than the flood season control level on trial basis to increase the discharge to downstream and improve the river environment during this season. 4. The results of the survey about fish showed that almost of the half of fish in the reservoir is alien fish, bluegill and they endanger indigenous fish. To get rid of bluegill, we catch fish during the water level declining operation to the flood season control level from the normal water level. We use the fixed nets to catch fish. This way was newly developed for this purpose and it gives less damage to fish so that we can release indigenous fish into the river alive. We produce fertilizer from those alien fish and use it to grow vegetables in the garden at our office, then we use them for our lunch. We are also experimenting and researching the effective use of the fertilizer with local farmers. By operating the water level in the reservoir higher than the flood season control level, we can expand and create spawning grounds in shallow areas of the reservoir. On top of this, we put some artificial floating islands in the reservoir to secure spawning grounds that can catch up with the water level fluctuation.

Journal of radiation research. 2001, 42(4), p.526

Journal of radiation research. 1998, 39(4), p.401

Journal of radiation research. 1998, 39(4), p.305

Journal of radiation research. 1997, 38(4), p.363

A case of hyperfunctioning parathyroid carcinoma was found in a 78-year-old female who had suffered from hypercalcemia for 5 years. She died of renal failure and pulmonary edema. Autopsy revealed an encapsulated tumor arising from the left upper parathyroid gland. Histologically, fibrous trabeculae, capsular invasion and blood vessel invasion were occasionally present in this tumor, suggesting that this tumor was malignant. However, mitotic figures were rarely observed. We reviewed reported cases of parathyroid carcinoma and discussed about the significance of mitosis for diagnosis., Acta medica Nagasakiensia. 1989, 34(2-4), p.113-116

磁石片付きクローラで壁面に吸着して走行する, 壁面移動機構の開発を進めている.従来の磁石付きクローラは, クローラ両端の磁石片に負荷荷重が集中するため, クローラ長さと無関係に磁石片2個分の吸着力しか持たなかった.そこで本研究では, 磁石片の個数に比例した吸着力をもつ負荷分散クローラを提案した.このクローラの特徴は, 移動機構を壁面から引き離す方向に作用する負荷荷重を, 壁面に吸着している全ての磁石片に分散して直接伝達する点である.実験によって負荷分散の機能が有効に働き, 吸着力が磁石片の個数すなわちクローラ長さにほぼ比例することを確認した.次にこの負荷分散クローラを用いて移動機構を製作した.その結果, 模擬壁面の傾斜にかかわらず安定に走行した.