Masaki Sakai

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We have found that the cricket Gryllus bimaculatus shows an immobile posture, so-called thanatosis. Thanatosis was reflexly elicited by gently holding the forelegs and pronotum of the cricket. During thanatosis, the respiration rate decreased markedly while the heart rate doubled compared with the resting state. Animals in the state of extreme rigidity were(More)
When exposed to light, planarians display a distinctive light avoidance behavior known as negative phototaxis. Such behavior is temporarily suppressed when animals are decapitated, and it is restored once the animals regenerate their heads. Head regeneration and the simple but reproducible phototactic response of planarians provides an opportunity to study(More)
The suitability of ejaculated and epididymal stallion spermatozoa for cooled storage (5 degrees C) and cryopreservation was examined in 5 ejaculates from each of 6 stallions and in spermatozoa recovered from the cauda epididymidis after castration of these stallions. The percentage of progressively motile spermatozoa, examined by subjective estimation(More)
We have investigated the morphology and physiology of the genitalia of the male cricket to establish a basis for neuroethological study of its reproductive behaviour. First, the structure of the phallic complex, including the dorsal pouch, guiding rod, epiphallus, ventral lobes and median pouch, are described, as are the muscles, cuticle, membranes and(More)
1. Responses evoked by stimulation of the cerebellar and thalamic nuclei were recorded by microelectrodes introduced at various depths in the cerebral cortex of monkeys (Macaca mulatta) under light Nembutal anaesthesia. 2. Stimulation of the medial (fastigial) cerebellar nucleus produced, at a latency of 4–5 msec, deep thalamo-cortical (T-C) responses(More)
The cricket Gryllus bimaculatus displayed freezing (thanatosis) after struggling while the femoro-tibial joints of the walking legs were forcibly restrained. Myographic recording indicated that strong contraction of the flexor tibia muscle “leg flexion response” occurred under this restrained condition. During thanatosis, when the femoro-tibial joint was(More)
BACKGROUND AND OBJECTIVES This study examined the effects of moderate renal impairment on the pharmacokinetics and pharmacodynamics of canagliflozin in Japanese patients with type 2 diabetes mellitus. METHODS Japanese patients with stable type 2 diabetes (12 with moderate renal impairment and 12 with normal renal function or mild renal impairment) were(More)
The percentages of morphologically transferable embryos obtained from frozen-thawed demi-embryos which were embedded with or without agar, and from those with or without zonae pellucidae were 26.3% (5/19), 36.4% (8/22), 39.5% (15/38) and 40.0% (22/55), respectively. No significant differences were observed between these groups. Development to calves of(More)
Neurons of the prefrontal-premotor cortex, which had been studied electorophysiologically during a modified reaction time task, were identified by intracellular pressure micro-injection of horseradish peroxidase (HRP). The cells were classified into those showing a sustained vs. transient change in activity during performance of the task. Cells showing a(More)