MATERIALS AND METHODS: Eighty patients for laparoscopic surgery with at least one of the determined risks (nonsmoker, female, previous PONV/motion sickness, or postoperative opioid use) were randomized into either an active or sham group. At the end of surgery, Reletex electrical acustimulation was placed at the P6 acupoint. The active group had grade 3 strength and the sham group had inactivated electrodes covered by silicone. It was worn for 24 h following surgery. PONV scores were recorded.
RESULTS: The active group had significantly shorter durations of surgery and lower PONV incidence over 24 h (35.1% versus 64.9%, P = 0.024) and this was attributed to the lower incidence of nausea (31.4% versus 68.6%, P = 0.006). The overall incidence of vomiting was not significantly different between the groups, but it was higher in the sham group of patients with PONV risk score 3 (23.9%, P = 0.049).
CONCLUSION: In patients at high risk for PONV, P6 acupoint electrical stimulation lowers the PONV incidence by reducing the nausea component. However, this reduction in nausea is not related to increasing PONV risk scores.
METHODS: Fourteen datasets extracted from three published papers were used in a meta-analysis to examine the cyclic behaviour of the Arabidopsis thaliana photosynthesis-related gene CAB2 and the clock oscillator genes TOC1 and LHY in T cycles and N-H cycles.
KEY RESULTS: Changes in the rhythms of CAB2, TOC1 and LHY in plants subjected to non-24-h light:dark cycles matched the hypothesized changes in their behaviour as predicted by the solar clock model, thus validating it. The analysis further showed that TOC1 expression peaked ∼5·5 h after mid-day, CAB2 peaked close to noon, while LHY peaked ∼7·5 h after midnight, regardless of the cycle period, the photoperiod or the light:dark period ratio. The solar clock model correctly predicted the zeitgeber timing of these genes under 11 different lighting regimes comprising combinations of seven light periods, nine dark periods, four cycle periods and four light:dark period ratios. In short cycles that terminated before LHY could be expressed, the solar clock correctly predicted zeitgeber timing of its expression in the following cycle.
CONCLUSIONS: Regulation of gene phases by the solar clock enables the plant to tell the time, by which means a large number of genes are regulated. This facilitates the initiation of gene expression even before the arrival of sunrise, sunset or noon, thus allowing the plant to 'anticipate' dawn, dusk or mid-day respectively, independently of the photoperiod.