Hokkaido University

Shionogi’s once-daily 3CL protease inhibitor hit on a primary endpoint in a late-stage trial as a post-exposure prophylaxis treatment for Covid-19 after failing a Phase 3 study in May. The oral antiviral, ensitrelvir, showed a statistically significant decrease in the proportion of patients with a symptomatic infection through 10 days after being exposed to household members with Covid-19 when compared to placebo. The company described the drug as well-tolerated with no new safety signals. Shionogi’s senior VP and head of clinical development Simon Portsmouth said in a statement that “there are currently no oral antiviral medications approved for post-exposure prophylactic use,” adding that “there is a need for convenient, preventive approaches to protect ourselves and those close to us from contracting SARS-CoV-2.” Ensitrelvir, marketed as Xocova and developed in a joint research collaboration with Hokkaido University, scored an emergency regulatory approval in Japan in 2022 before garnering a full approval in March for the treatment of Covid-19. But the drug failed in the NIH-partnered SCORPIO-HR study when it didn’t show a statistically significant reduction in patients being completely clear of symptoms for at least two days when the drug was given within three days of symptoms starting. However, a separate analysis showed that patients had no sign of six different symptoms for at least one day, earning a p-value of 0.05 compared to placebo. The trial showed other positives, according to the company, including a reduction from baseline in viral RNA levels and no symptomatic viral rebounds in patients.

A team of researchers has developed a gel electret capable of stably retaining a large electrostatic charge. The team then combined this gel with highly flexible electrodes to create a sensor capable of perceiving low-frequency vibrations (e.g., vibrations generated by human motion) and converting them into output voltage signals. This device may potentially be used as a wearable healthcare sensor. A team of researchers from NIMS, Hokkaido University and Meiji Pharmaceutical University has developed a gel electret capable of stably retaining a large electrostatic charge. The team then combined this gel with highly flexible electrodes to create a sensor capable of perceiving low-frequency vibrations (e.g., vibrations generated by human motion) and converting them into output voltage signals. This device may potentially be used as a wearable healthcare sensor. Interest in the development of soft, lightweight, power-generating materials has been growing in recent years for use in soft electronics designed for various purposes, such as healthcare and robotics. Electret materials capable of stably retaining electrostatic charge may be used to develop vibration-powered devices without external power sources. NIMS has been leading efforts to develop a low-volatility, room-temperature alkyl-π liquid composed of a π-conjugated dye moiety and flexible yet branched alkyl chains (a type of hydrocarbon compound). The alkyl-π liquids exhibit excellent charge retention properties, can be applied to other materials (e.g., through painting and impregnation) and are easily formable. However, when these liquids have been combined with electrodes to create flexible devices, they have proven difficult to immobilize and seal, resulting in leakage issues. Moreover, the electrostatic charge retention capacities of alkyl-π liquids needed to be increased in order to improve their power generation capabilities. The research team recently succeeded in creating an alkyl-π gel by adding a trace amount of a low-molecular-weight gelator to an alkyl-π liquid. The elastic storage modulus of this gel was found to be 40 million times that of its liquid counterpart, and it could be simplified fixation and sealed. Moreover, the gel-electret obtained by charging this gel achieved a 24% increase in charge retention compared to the base material (i.e., the alkyl-π liquid), thanks to the improved confinement of electrostatic charges within the gel. The team then combined flexible electrodes with the gel-electret to create a vibration sensor. This sensor was able to perceive vibrations with frequencies as low as 17 Hz and convert them into an output voltage of 600 mV -- 83% higher than the voltage generated by an alkyl-π liquid electret-based sensor. In future research, the team aims to develop wearable sensors capable of responding to subtle vibrations and various strain deformations by further improving the charging electret characteristics (i.e., charge capacity and charge life) and strength of the alkyl-π gel. Additionally, since this gel is recyclable and reusable as a vibration sensor material, its use is expected to help promote a circular economy.

Meandering ocean currents play an important role in the melting of Antarctic ice shelves, threatening a significant rise in sea levels. Meandering ocean currents play an important role in the melting of Antarctic ice shelves, threatening a significant rise in sea levels. A new study published in Nature Communications has revealed that the interplay between meandering ocean currents and the ocean floor induces upwelling velocity, transporting warm water to shallower depths. This mechanism contributes substantially to the melting of ice shelves in the Amundsen Sea of West Antarctica. These ice shelves are destabilizing rapidly and contributing to sea level rise. Led by Taewook Park and Yoshihiro Nakayama, an international team of researchers from the Korea Polar Research Institute, Hokkaido University, and Seoul National University employed advanced ocean modeling techniques to investigate the underlying forces behind the rapid melting ice shelves. In a departure from prior assumptions linking ice shelf melting primarily to winds over the Southern Ocean, this study underscores the significant role played by the interactions between meandering ocean currents and the ocean floor in driving the melting process. The Pine Island and Thwaites ice shelves are among the fastest-changing in Antarctica and are of particular interest due to their vulnerability to warming ocean waters. They act as massive barriers restraining the glaciers behind them from flowing into the ocean. However, their rapid melting and potential collapse pose a significant threat to coastal communities worldwide because of the resulting rise in global sea levels. The study focused on the role of a layer of warm water beneath the frigid surface waters, known as the 'modified Circumpolar Deep Water,' in melting these ice shelves from below. "The intensity and trajectory of ocean currents encircling the ice shelves directly govern the influx of warm water, thereby intricately shaping their rate of melting" explains Taewook. This shows the importance of the ocean in understanding and addressing the impacts of climate change. The researchers paid attention to the 'thermocline depth', which is the depth of the interface between warmer deep waters and cooler surface waters. Variations in thermocline depth significantly affect the influx of warm water toward the ice shelves. Until now, it has been believed that intensified westerly winds north of the Amundsen Sea propelled ocean currents along the shelf break, carrying warmer water toward ice shelf cavities. This phenomenon is particularly pronounced during El Niño events. "Our findings challenge conventional wisdom," Nakayama asserts. "Our study underscores that the interplay between meandering ocean currents and the ocean floor generates upwelling velocity, bringing warm water to shallower depths. Subsequently, this warm water reaches the ice-ocean interface, accelerating ice shelf melting." Nakayama concludes, "This internal oceanic process driving ice shelf melting introduces a novel concept. With this in mind, we have to reevaluate winds driving Antarctic ice loss, which can significantly impact future projections."