RESUMEN
We know that entrainment, a stable phase relationship with an environmental cycle, must be established for a biological clock to function properly. Phase response curves (PRCs), which are plots of phase shifts that result as a function of the phase of a stimulus, have been created to examine the mode of entrainment. In circadian rhythms, single-light pulse PRCs have been obtained by giving a light pulse to various phases of a free-running rhythm under continuous darkness. This successfully explains the entrainment to light-dark cycles. Some organisms show circannual rhythms. In some of these, changes in photoperiod entrain the circannual rhythms. However, no single-pulse PRCs have been created. Here we show the PRC to a long-day pulse superimposed for 4 weeks over constant short days in the circannual pupation rhythm in the varied carpet beetle Anthrenus verbasci. Because the shape of that PRC closely resembles that of the Type 0 PRC with large phase shifts in circadian rhythms, we suggest that an oscillator having a common feature in the phase response with the circadian clock, produces a circannual rhythm.
Asunto(s)
Escarabajos/fisiología , Periodicidad , Animales , Escarabajos/crecimiento & desarrollo , Oscuridad , Larva/crecimiento & desarrollo , Luz , Metamorfosis Biológica/fisiología , Estimulación Luminosa , Pupa/crecimiento & desarrollo , Estaciones del AñoRESUMEN
This paper describes the detailed characteristics of the circannual pupation rhythm in Anthrenus verbasci determined by laboratory experiments under various photoperiods and temperatures. The frequency distribution of larval duration showed a periodic pattern over 2-3 years and the period was 37-40 weeks under a constant short-day photoperiod (light:dark 12:12) at 20 degrees C. This rhythm showed temperature compensation to some extent under a short-day photoperiod between 17.5 degrees C and 27.5 degrees C. Under alternations of a long-day (light:dark 16:8) and a short-day photoperiod, pupation occurred 21-24.5 weeks after transfer from a long-day to a short-day photoperiod. Therefore, we concluded that the timing of pupation in A. verbasci is controlled by a circannual rhythm and its zeitgeber is a change in photoperiod. Furthermore, when larvae were transferred from a long-day to a short-day photoperiod at various ages, the larval duration after the photoperiodic transfer depended on the time of the transfer. This difference can be explained by phase-dependent phase shifts in the circannual rhythm.
Asunto(s)
Escarabajos/fisiología , Metamorfosis Biológica/fisiología , Adaptación Fisiológica , Animales , Larva/crecimiento & desarrollo , Fotoperiodo , Pupa/crecimiento & desarrollo , TemperaturaRESUMEN
An elderly woman with a history of cholecystectomy and a re-operation for postoperative peritonitis underwent extracorporeal shock wave lithotripsy (ESWL) for right and left renal pelvic calculi, 11 x 6 and 12 x 5 mm in size, to which 2400 and 1400 shots at 20 kV were given, respectively, on the same day. During the evening after the operation, the patient started to complain of upper abdominal pain. Laboratory examination on the next day revealed elevations in blood and urine amylase levels and a diagnosis of pancreatitis was made. Conservative treatment, including administration of protease inhibitor, did not improve her symptoms; abdominal distension became marked and she underwent laparotomy. Necrosection and indwelling of several drain tubes in abdomen were performed with an operative diagnosis of acute necrotic pancreatitis. With daily irrigation of drain tubes and treatment for methicillin-resistant Staphyloococcus aureus infection of the lungs and abdominal cavity, septicemia and duodenal fistula, the patient gradually recovered and was discharged on postoperative day 151. It was suggested that ESWL was responsible for the acute pancreatitis. Either an obstruction of the pancreatic duct by fragments of common duct stone, or mechanical injury of the pancreas due to adhesion between the pancreas and surrounding tissue caused by the lapalotomy, was considered as a possible cause of pancreatitis. To our knowledge, there has been no previous report of severe acute pancreatitis and the present case suggests that ESWL may cause severe pancreatic even in cases without stone shadow in the bile, common duct or pancreatic duct.