Suppressive effect of azithromycin on Plasmodium berghei mosquito stage development and apicoplast replication

<p>Abstract</p> <p>Background</p> <p>Azithromycin (AZM) is a macrolide antibiotic that displays an excellent safety profile even in children and pregnant women and has been shown to have anti-malarial activity against blood stage <it>Plasmodium falciparum</it>. This study evaluated the transmission-blocking effect of AZM using a rodent malaria model.</p> <p>Methods</p> <p>AZM-treated mice infected with <it>Plasmodium berghei </it>were exposed to <it>Anopheles stephensi </it>mosquitoes, followed by the observation of parasite development at different phases in the mosquito, i.e., ookinetes in the midgut, oocysts on the midgut, and sporozoites in the midgut and salivary glands. Furthermore, to evaluate the effect on organelle replication of each stage, quantitative real-time PCR analysis was performed.</p> <p>Results</p> <p>The inhibitory effect of AZM was noticeable in both gametocyte-ookinete transformation in the midgut and sporozoite production in the oocyst, while the latter was most remarkable among all the developmental phases examined. Real-time PCR analysis revealed that AZM suppressed apicoplast replication at the period of sporozoite production in oocysts.</p> <p>Conclusions</p> <p>AZM inhibits parasite development in the mosquito stage, probably through the same mechanism as in the liver and blood stages. Such a multi-targeting anti-malarial, along with its safety, would be ideal for mass drug administration in malaria control programmes.</p

A Study on Teaching Program to Acquirement of Water Familiarization in Elementary School

早大学位記番号:新9211博士(スポーツ科学)早稲田大

Probability Occurrence of Estimated Lightning Surge Current at Lightning Rod before and after Installing Dissipation Array System (DAS)

Lightning surges in a telecommunication building were observed before and after installing a dissipation array system (DAS) for lightning in winter. A portable digitizing oscilloscope and a multichannel digitizing oscilloscope with an optical fiber system were used for the observation. The observed results from winter 1991 to winter 1996 show that the peak value occurrence probability at an antenna tower leg was not changed before and after installing the DAS and the occurrence at a pillar of the building was decreased a bit by installing the DAS. The peak value of the lightning current at the lightning rod of the building was estimated from the surges observed at the lightning rods, at a leg of each telecommunication tower, and at a building pillar. The occurrence calculated from this value was almost the same before and after installing the DAS.1998 International Symposium on Electromagnetic Compatibility, 24-28 August, 1998, Denver, CO, US

The Modulation of Corticospinal Excitability during Motor Imagery of Actions with Objects

We investigated whether corticospinal excitability during motor imagery of actions (the power or the pincer grip) with objects was influenced by actually touching objects (tactile input) and by the congruency of posture with the imagined action (proprioceptive input). Corticospinal excitability was assessed by monitoring motor evoked potentials (MEPs) in the first dorsal interosseous following transcranial magnetic stimulation over the motor cortex. MEPs were recorded during imagery of the power grip of a larger-sized ball (7 cm) or the pincer grip of a smaller-sized ball (3 cm)—with or without passively holding the larger-sized ball with the holding posture or the smaller-sized ball with the pinching posture. During imagery of the power grip, MEPs amplitude was increased only while the actual posture was the same as the imagined action (the holding posture). On the other hand, during imagery of the pincer grip while touching the ball, MEPs amplitude was enhanced in both postures. To examine the pure effect of touching (tactile input), we recorded MEPs during imagery of the power and pincer grip while touching various areas of an open palm with a flat foam pad. The MEPs amplitude was not affected by the palmer touching. These findings suggest that corticospinal excitability during imagery with an object is modulated by actually touching an object through the combination of tactile and proprioceptive inputs

大学体育における水泳授業によってクロールと平泳ぎを「続けて長く泳ぐこと」ができるようになるプロセス ─ 当事者の語りの分析から ─

　　The purpose of this study is to elucidate through an interview-based survey the process by which someone unable to swim becomes able to swim for long periods doing front crawl and breaststroke. The survey participant was a woman who could not swim a meter before taking university swimming classes. Owing to the swimming classes, she learnt to swim for long periods doing front crawl and breaststroke. Data was collected via a semi-structured interview. Trajectory Equifinality Modeling (TEM) was used for the analysis. 　　The following three conclusions were made: 　　1) Students who could not swim at all became able to swim front crawl by first learning to breathe underwater. 　　2) For breaststroke, the students timed their breathing by watching others swim, thereby learning to time their breathing with their swimming strokes. 　　3) Those who could not swim became able to swim for long periods doing front crawl and breaststroke, by going through the following three stages: a stage at which they could not think of anything, a stage at which they swam while thinking, and a stage at which they could swim without thinking

集中講義で開講される水泳授業が大学生の泳力に与える効果

　　This study clarifies the effects of intensive swimming classes on university students’ swimming ability. The results of our analysis are： 　　In front crawl swimming activity, swimming velocity (V) and stroke rate (SR) decreased significantly, and stroke length (SL) improved significantly. In movement evaluation, glide, stroke movement, and total score improved significantly, but breathing movement, kick movement, and body position showed no significant difference. In breaststroke, there was no significant difference in V, but SL improved significantly, and SR decreased significantly. In motion evaluation, pull movement, and total score improved significantly, but kick movement and body position showed no significant difference. 　　These results suggest that the classes did not affect the improvement of students’ V, but they did have a certain effect on improving swimming form