Polycystic kidney disease 2-like 1 channel contributes to the bitter aftertaste perception of quinine.

Bitterness is an important physiological function in the defense responses to avoid toxic foods. The taste receptor 2 family is well known to mediate bitter taste perception in Type II taste cells. Here, we report that the polycystic kidney disease 2-like 1 (PKD2L1) channel is a novel sensor for the bitter aftertaste in Type III taste cells. The PKD2L1 channel showed rebound activation after the washout of quinine, a bitter tastant, in electrophysiological whole-cell recordings of the PKD2L1-expressing HEK293T cells and Ca2+-imaging analysis of Type III taste cells isolated from wild-type PKD2L1 mice. In the short-term two-bottle preference and lick tests in vivo, the wild-type mice avoided normal water while the PKD2L1-knockout mice preferred normal water after they ingested the quinine-containing water. These results may explain the new mechanism of the quinine-triggered bitter aftertaste perception in Type III taste cells.

Simultaneous monitoring of activity and heart rate variability in depressed patients: A pilot study using a wearable monitor for 3 consecutive days.

INTRODUCTION: Reduced activity and sleep-wake rhythm disturbances are essential features of depressive episodes. In addition, alterations in heart rate variability (HRV) have been implicated in depression. By using a wearable sensor that monitors 3-dimensional acceleration and HRV simultaneously, we examined the activity and HRV indices in depressive episode of mood disorders. METHODS: Participants were 19 patients (13 major depressive disorder [MDD] and 6 bipolar depression; 11 females) and 18 controls (9 females) matched for age and ethnicity (all Japanese) who completed 3 consecutive days of all-day monitoring by a small and light device attached to the chest. RESULTS: Activity magnitude was significantly reduced while lying/resting time was increased in depressed patients, compared with controls. When males and females were examined separately, male, but not female, patients showed significant reduction in activity. HRV indices such as R-R interval and high-frequency power (a parameter for the parasympathetic system) were significantly decreased in patients than in controls. Significant differences in activity and HRV indices were seen only in males. Sympathetic load during sleep significantly correlated with damped rest-activity rhythm in depressed patients. LIMITATIONS: The number of participants was small, and the majority of the participants were taking psychotropic medications. CONCLUSIONS: We obtained evidence for reduced activity, increased lying/resting time, and reduced HRV indices in male depressed patients. The simultaneous monitoring for activity and HRV suggested greater sympathetic load during sleep is associated with damped rest-activity rhythm (increased activity during sleep and decreased daytime activity), which might be a characteristic pathology of depression.

Clinical Usefulness of New R-R Interval Analysis Using the Wearable Heart Rate Sensor WHS-1 to Identify Obstructive Sleep Apnea: OSA and RRI Analysis Using a Wearable Heartbeat Sensor.

Obstructive sleep apnea (OSA) is highly associated with cardiovascular diseases, but most patients remain undiagnosed. Cyclic variation of heart rate (CVHR) occurs during the night, and R-R interval (RRI) analysis using a Holter electrocardiogram has been reported to be useful in screening for OSA. We investigated the usefulness of RRI analysis to identify OSA using the wearable heart rate sensor WHS-1 and newly developed algorithm. WHS-1 and polysomnography simultaneously applied to 30 cases of OSA. By using the RRI averages calculated for each time series, tachycardia with CVHR was identified. The ratio of integrated RRIs determined by integrated RRIs during CVHR and over all sleep time were calculated by our newly developed method. The patient was diagnosed as OSA according to the predetermined criteria. It correlated with the apnea hypopnea index and 3% oxygen desaturation index. In the multivariate analysis, it was extracted as a factor defining the apnea hypopnea index (r = 0.663, p = 0.003) and 3% oxygen saturation index (r = 0.637, p = 0.008). Twenty-five patients could be identified as OSA. We developed the RRI analysis using the wearable heart rate sensor WHS-1 and a new algorithm, which may become an expeditious and cost-effective screening tool for identifying OSA.

Nanoscale chiral surface relief of azo-polymers with nearfield OAM light.

An optical vortex with orbital angular momentum (OAM) can be used to induce microscale chiral structures in various materials. Such chiral structures enable the generation of a nearfield vortex, i.e. nearfield OAM light on a sub-wavelength scale, thereby leading to further nanoscale mass-transport. We report on the formation of a nanoscale chiral surface relief in azo-polymers due to nearfield OAM light. The resulting nanoscale chiral relief exhibits a diameter of ca. 400 nm, which corresponds to less than 1/5-1/6th of the original chiral structure (ca. 2.1 µm). Such a nanoscale chiral surface relief is established by the simple irradiation of uniform visible plane-wave light with an intensity of <500 mW/cm2.

Analysis of variability of R-R intervals for the diagnosis of atrial fibrillation: A new algorithm.

Differences in successive R-R intervals (RRIs) were normalized by RRIs before and after the indexing beats (normalized DRs) in individuals with normal sinus rhythm (NSR) and 98.89% of normalized DRs were found to distribute within mean±0.100 (≒mean±3SD), whereas 73.47% were out of this range in atrial fibrillation (AF). When 7 out 20 normalized DRs fell outside of 0.000±0.100, NSR (n=129) and AF (n=108) could be discriminated with high sensitivity, specificity, and predictive values (>99.0% for all). This method will be used in detecting AF candidates from a small number of heart beats or arterial pulses.

Fast scanning method for one-dimensional surface profile measurement by detecting angular deflection of a laser beam.

A fast scanning method for one-dimensional surface profile measurement is proposed. The profile is measured by integration of a slope distribution of the surface obtained from angular deflection of a scanning laser beam. A scanning optical system that consists principally of a spherical concave mirror and a rotating scanner mirror has reasonably low cost and is insensitive to mechanical vibration because of its high-speed scanning, of the order of milliseconds. A surface profile of a polygonal mirror along a 5-mm width was measured with the scanning method and with an interferometer. The root-mean-square difference between the two measured results is 0.98 nm.