Extension of the established period of diacetyl adaptation by oxygen intermediates in the nematode Caenorhabditis elegans.

After pre-exposure to the odorant diacetyl, the nematode Caenorhabditis elegans showed a decline in chemotactic responses to diacetyl, a phenomenon known as diacetyl adaptation. In the present study, we found that the established period of diacetyl adaptation in nematodes increased with the breeding temperature. When wild-type (N2) nematodes were bred at 15°C, adaptation was observed from the young adult (YA) to the 3-day-old adult that is reached 3 days after the YA stage. On breeding nematodes at 20°C and 25°C, adaptation was observed between the YA and 5-day-old adult and between the YA and the 7-day-old adult, respectively. Breeding temperature has been shown to correlate with the rate of aging in nematodes, which is related to the level of oxygen consumption. Accordingly, long-lived isp-1 and clk-1 mutants that demonstrate decreased levels of oxygen consumption showed a shorter established period of adaptation than N2 nematodes, whereas short-lived gas-1 and mev-1 mutants that have a hypersensitive response to oxygen showed a longer period of adaptation than the N2. Moreover, the established period of diacetyl adaptation in N2 nematodes was shortened by the antioxidant α-lipoic acid. These results suggest that oxygen intermediates, which are produced by oxygen consumption, play a significant role in diacetyl adaptation. Although this is only one of many factors that regulate diacetyl adaptation, such as the release of neurotransmitters and changes in intracellular conditions, the acquisition of this adaptation requires an increase in the intensity of moderate oxygen signals.

Preliminary clinical evaluation of a video transmission system for home visits.

A portable video transmission system based on a hand-held computer and cellular telephone was developed for use with patients undergoing rehabilitation at home. It was designed to be simple to operate, for use by nurses on home care visits. The whole system can be held in one hand, and video pictures can be recorded and transmitted with the touch of a few buttons. The quality of the transmitted pictures and the feasibility of the system were clinically evaluated by physical therapists and nurses. Three image transmission scenes were used to evaluate the system: turning over in bed; walking; and raising and lowering a shoulder. Nurses reported that the system was easy to carry and simple to use. Physiotherapists found the system to be useful in making a judgement about the patient's condition. The patients were all enthusiastic about the system. The increased interaction had the effect of improving the patients' desire to continue their in-home rehabilitation.

Interstitial magnetic resonance lymphography: comparative animal study of gadofluorine 8 and gadolinium diethylenetriamine-pentaacetic acid.

PURPOSE: We evaluated the usefulness of gadofluorine 8 (G8) and gadolinium diethylenetriamine-pentaacetic acid (Gd-DTPA) for interstitial magnetic resonance lymphography (MRL). METHOD: Phantom imaging studies were conducted with G8 and Gd-DTPA corresponding to 0.1-0.005 micromol Gd/mL, and signal intensity was measured. Popliteal lymph node (PLN) accumulation was investigated in rabbits. Imaging was performed before and after subcutaneous administration of G8 (50 micromol Gd/mL) and Gd-DTPA (50 micromol Gd/mL). Contrast enhancement ratio measurements of PLN were determined both prior to and following the administration. RESULTS: Signal intensity of phantom for G8 are higher than those for Gd-DTPA from 0.1 to 0.002 micromol Gd/mL (P < 0.0001). Imaging after 5 minutes can clearly detect PLN accumulation on two contrast agents. Nevertheless, PLN accumulation of Gd-DTPA disappeared after about 30 minutes. A statistically significant difference between G8 and Gd-DTPA can be seen from 5 to 90 minutes in CER (P < 0.0001). PLN became clearly visible at 5 minutes after the injection of G8 and Gd-DTPA. Nevertheless, PLN accumulation of Gd-DTPA disappeared at 30 minutes. Otherwise, PLN accumulation of G8 continued up to 90 minutes. CONCLUSION: These studies indicated that G8 was more suitable than Gd-DTPA as a contrast agent for interstitial MRL up to 90 minutes.