Suppressive effects of violet light transmission on myopia progression in a mouse model of lens-induced myopia.

The prevalence of myopia has been steadily increasing for several decades, and this condition can cause extensive medical and economic issues in society. Exposure to violet light (VL), a short wavelength (360-400 nm) of visible light from sunlight, has been suggested as an effective preventive and suppressive treatments for the development and progression of myopia. However, the clinical application of VL remains unclear. In this study, we aimed to investigate the preventive and suppressive effects of VL on myopia progression. Various transmittances of VL (40%, 70%, and 100%) were tested in C57BL/6J mice with lens-induced myopia (LIM). Changes in the refractive error, axial length, and choroid thickness during the 3-week LIM were measured. The myopic shift in refractive error and difference in axial length between the 0 and -30 diopter lens was lessened in a transmission-dependent manner. Choroidal thinning, which was observed in myopic conditions, was suppressed by VL exposure and affected by its transmission. The results suggest that myopia progression can be managed using VL transmittance. Therefore, these factors should be considered for the prevention and treatment of myopia.

Human Flow Dataset Reveals Changes in Citizens' Outing Behaviors including Greenspace Visits before and during the First Wave of the COVID-19 Pandemic in Kanazawa, Japan.

Greenspaces, including parks, provide various socio-ecological benefits such as for aesthetics, temperature remediation, biodiversity conservation, and outdoor recreation. The health benefits of urban greenspaces have received particular attention since the onset of the COVID-19 pandemic, which has triggered various movement restrictions and lifestyle changes, including regarding the frequency of people's visits to greenspaces. Using mobile-tracking GPS data of Kanazawa citizens, we explored how citizens' behaviors with respect to outings changed before and during Japan's declaration of a COVID-19 state of emergency (April-May 2020). We also examined citizens' greenspace visits in relation to their travel distance from home. We found that Kanazawa citizens avoided going out during the pandemic, with a decrease in the number, time, and distance of outings. As for the means of transportation, the percentage of outings by foot increased on both weekdays and holidays. While citizens refrained from going out, the percentage change of the percentage in large greenspace visits increased very slightly in 2020. As for greenspace visitation in 2020 compared to 2019, we found that citizens generally visited greenspaces closer to their homes, actually increasing visitation of nearby (within 1000 m) greenspaces. This study of how outing behaviors and greenspace use by Kanazawa citizens have changed underscores the value of nearby greenspaces for physical and mental health during movement restrictions under the pandemic.

Intensified East Asian winter monsoon during the last geomagnetic reversal transition.

The strength of Earth's magnetic dipole field controls galactic cosmic ray (GCR) flux, and GCR-induced cloud formation can affect climate. Here, we provide the first evidence of the GCR-induced cloud effect on the East-Asian monsoon during the last geomagnetic reversal transition. Bicentennial-resolution monsoon records from the Chinese Loess Plateau revealed that the summer monsoon (SM) was affected by millennial-scale climate events that occurred before and after the reversal, and that the winter monsoon (WM) intensified independently of SM variations; dust accumulation rates increased, coinciding with a cooling event in Osaka Bay. The WM intensification event lasted about 5000 years across an SM peak, during which the Earth's magnetic dipole field weakened to <25% of its present strength and the GCR flux increased by more than 50%. Thus, the WM intensification likely resulted from the increased land-ocean temperature gradient originating with the strong Siberian High that resulted from the umbrella effect of increased low-cloud cover through an increase in GCR flux.

Quantitative prediction of ionization effect on human skin permeability.

Although skin permeability of an active ingredient can be severely affected by its ionization in a dose solution, most of the existing prediction models cannot predict such impacts. To provide reliable predictors, we curated a novel large dataset of in vitro human skin permeability coefficients for 322 entries comprising chemically diverse permeants whose ionization fractions can be calculated. Subsequently, we generated thousands of computational descriptors, including LogD (octanol-water distribution coefficient at a specific pH), and analyzed the dataset using nonlinear support vector regression (SVR) and Gaussian process regression (GPR) combined with greedy descriptor selection. The SVR model was slightly superior to the GPR model, with externally validated squared correlation coefficient, root mean square error, and mean absolute error values of 0.94, 0.29, and 0.21, respectively. These models indicate that Log D is effective for a comprehensive prediction of ionization effects on skin permeability. In addition, the proposed models satisfied the statistical criteria endorsed in recent model validation studies. These models can evaluate virtually generated compounds at any pH; therefore, they can be used for high-throughput evaluations of numerous active ingredients and optimization of their skin permeability with respect to permeant ionization.

Evaluation of the suppressive effect on bitter taste of gluconate.

Gluconate is used as an additive in a wide range of processed foods. In this study, we investigated its utility as a taste-improving substance. To determine whether it has a suppressive effect on bitter taste, sensory evaluations were performed by human subjects. When gluconate was added to a quinine-HCl (QHCl) solution, the taste intensity decreased, but this effect was not observed when it was added to caffeine and to naringin solutions. Then we investigated the mechanism of suppression by performing behavioral and electrophysiological assays on mice. In mice, the addition of gluconate improved the taste preference for and reduced the gustatory nerve response to QHCl. In sum, gluconate had a suppressive effect on the bitter taste of QHCl, which might have been caused by depression of gustatory nerve activity.

Involvement of specific transport system on uptake of lactone form of SN-38 in human intestinal epithelial cell line Caco-2.

The aim of this study was to elucidate the characteristics of the transport of lactone and carboxylate forms of SN-38 (SN-38L and SN-38C, respectively), a metabolite of irinotecan hydrochloride (CPT-11), with the human intestinal epithelial cell line, Caco-2. We examined SN-38L and SN-38C uptake from the apical side into Caco-2, and the effects of various compounds on the uptake of SN-38L. SN-38L and SN-38C in the cells were determined by HPLC with a fluorescence detector. When either SN-38L (0.5 µM) or SN-38C (0.5 µM) was added extracellularly at 37°C, the accumulation of SN-38L into the cells was about 10-fold higher than that of SN-38C, suggesting a dominant role of the lactone form in the uptake of SN-38 into Caco-2. The accumulation of SN-38L in Caco-2 increased time-dependently up to 10 min at 37°C, whereas the accumulation markedly decreased at 4°C. The initial uptake rate of SN-38L approached saturation at high concentrations with Michaelis-Menten constant and 'Hill coefficient,' 2.84±1.00 µM and 2.13±1.14, respectively (mean±S.E.). The accumulation of SN-38L was markedly inhibited by baicalin, an active ingredient of a Chinese herbal medicine, Hange-Shashin-To, as well as CPT-11. The type of inhibition by baicalin was competitive. In contrast, concomitant sulfobromophthalein, taurocholate and estrone 3-sulfate significantly increased SN-38L uptake. These results suggest that apical uptake of SN-38 by Caco-2 is dominantly performed as a lactone form through a specific transporter, which is competitively inhibited by baicalin.