[Development of a One-minute Educational Video for Eye-drop Instillation and Changes in Instillation Behavior after Watching the Video].

We created a one-minute video titled "a simple method of eye-drop instillation" (video) for online instillation guidance, to compare the instillation method before and after study participants watch the video and verify the usefulness of watching the video. Moreover, we prepared a document questionnaire to investigate instillation habits and clarify instillation behavior. Study participants were randomly recruited from among students and faculty members via a poster posted at Tokushima Bunri University. The instillation behavior of the study participants was videotaped before and after they watched the video created by the authors. The images were played in a super slow motion, to confirm success or failure in instillation, drop sites, and eye-opening method. Of the 109 participants in the study, the successful instillation rate before and after watching the video was 55.0% and 69.7%, respectively. The use rate of wet wipes for finger disinfection before instillation increased from 0.0% before watching the video to 74.3% after watching the video. After watching the video, the blinking rate after instillation decreased from 95.4 to 45.0%, the rate of pressing the nasolacrimal duct increased from 2.8 to 77.1%, and the rate of wiping the drug solution spilled around the eyes increased from 89.9 to 98.2%. According to the questionnaire, 72.5% of the participants instilled one drop, 22.0% instilled two drops, and 5.5% instilled three drops or more. Watching the video significantly increased the successful instillation rate and improved instillation behavior. Thus, the video created by the authors can be used for online instillation guidance.

Difference in Ca2+ oscillation-inducing activity and nuclear translocation ability of PLCZ1, an egg-activating sperm factor candidate, between mouse, rat, human, and medaka fish.

Mouse phospholipase C, zeta 1 (PLCZ1), a strong candidate of egg-activating sperm factor, induces Ca(2+) oscillations and accumulates into formed pronucleus (PN) when expressed by cRNA injection. These activities were compared among mouse and human PLCZ1, newly cloned rat Plcz1, and medaka fish plcz1. The PLCZ1 proteins of the four species have an approximately homologous sequence of nuclear localization signal. However, the nuclear translocation ability was defective in rat, human, and medaka PLCZ1 expressed in mouse eggs. Rat PLCZ1 could not enter rat PN, whereas mouse PLCZ1 could. Mouse and human PLCZ1 translocated into the nucleus of COS-7 cells transfected with cDNA. There was little medaka PLCZ1 accumulated in the nucleus, and rat PLCZ1 was never located in the nucleus. All PLCZ1 proteins including fish could induce Ca(2+) oscillations in mouse eggs, but the activity was variable in the order of human >> mouse > medaka >> rat, estimated from minimal RNA concentration to induce Ca(2+) spikes. Ca(2+) oscillations by human PLCZ1 continued far beyond the time of PN formation (T(PN)), whereas those by mouse PLCZ1 ceased slightly before T(PN). High-frequency Ca(2+) spikes by overexpressed rat PLCZ1 stopped far before T(PN), possibly by feedback inhibition. Ca(2+) oscillations by fertilization of rat eggs stopped at T(PN), despite defective nuclear translocation of rat PLCZ1. Thus, PLCZ1 sequestration into PN participates in termination of Ca(2+) oscillations at the interphase of mouse embryos but does not always operate in other mammals, notably in rat embryos.

Roles for Potassium and Calcium Channels in the Initiation of Sperm Motility in Rainbow Trout.: (K+ /Ca2+ /channel/sperm motility/rainbow trout).

It is well known that the motility of spermatozoa in rainbow trout is suppressed by K+ . We showed here that although trout sperm are completely immotile in medium containing 5 mM K+ , motility was initiated by the subsequent addition of several mM Ca2+ , suggesting that both K+ and Ca2+ are related to the process of the initiation of sperm motility. It was further found that K+ channel blockers tetraethylammonium, nonyltriethylammonium, Ba2+ and Cs+ , as well as the Ca2+ channel blocker verapamil, inhibited the initiation of sperm motility at doses at which these reagents inhibit chnnel-related functions in other cells. However, Na+ channel blocker, tetrodotoxin and anion channel blocker 4, 4-diisothiocyatatostilbene-2, 2'-disulfonic acid inhibited the motility only at extremely high doses. These results suggest that transport of K+ and Ca2+ through ion channels at the plasma membrane of spermatozoa is the first event that triggers the initiation of sperm motility in rainbow trout.

Changes in Osmotic Pressure and Swelling in Horseshoe Crab Embryos During Development: (horseshoe crab embryo/swelling/water influx/perivitelline fluid/osmotic pressure).

Water influx accompanying the swelling of embryos during normal development of horseshoe crabs, Limulus polyphemus and Tachypleus tridentatus, following a rupture of the chorion, was analyzed. The increase in volume of perivitelline fluid during deveopment was about 90 percent of the increase in total embryo weight. Considerable water discharge was observed on drying the embryos in air and a reversible water influx occurred with a second immersion in sea water, even though the embryos died as a result of this treatment. Since the osmotic pressure of the perivitelline fluids decreased markedly during development until the end of swelling, a close correlation between swelling and osmotic pressure was recognized. These results indicate that certain osmoactive substances may be produced in the perivitelline fluid at the initial stage of swelling.