There is a high density of the cicada Cryptotympana facialis (Walker) (Hemiptera: Cicadidae) in urban parks in central Japan during summer. This cicada uses its stylet to pierce holes in the trunks of keyaki trees, Zelkova serrata and then feeds on the exuding xylem sap. Three ant species, Formica japonica Motschulsky, Lasius japonicus Santschi and Crematogaster matsumurai Forel (Hymenoptera: Formicidae) were observed aggregatively feeding on these exudates. In addition, two wasp species, Polistes jokohamae Radoszkowski (Hymenoptera: Vespidae), and Ampulex dissector (Thunberg) (Hymenoptera: Sphecidae) fed on the sap. These ants and wasps can therefore be classified as commensals. Two flower chafers, Protaetia brevitarsis (Lewis) and P. orientalis submarumorea (Burmeister) (Coleoptera: Scarabaeidae) were also observed displacing cicadas from their feeding sites and feeding on the exuding sap. Thus, these chafers can be classified as both commensals and kleptoparasites.
Summer and autumnal activity patterns of juvenile and adult Dryomys nitedula were investigated in the wild using infrared motion sensor cameras. The study revealed that the forest dormouse is mainly crepuscular and nocturnal during the summer and autumn. Foraging activity started on average 8 min before sunset in June and shifted towards 26 min after sunset in September. The activity usually ended 40 min before sunrise independently of the season. The investigative activity around the nestboxes had three main periods: one between 20:00 and 22:00, one around midnight between 00:00 and 01:00, and a third one before sunrise between 4:00 and 6:00. Diurnal activity was also recorded but it occurred mainly in autumn and was restricted to the nestbox entrance; animals never switched nestboxes during the day if not disturbed. During the night activity, dormice used to investigate almost all nestboxes within their territory. However they showed preferences for only a few nestboxes which were used more frequently as daytime resting sites.
Circadian and circaannual oscillations of tissue lipid peroxides (LPO) were studied in young male Wistar rats. The concentration of malondialdehyde, one of LPO degradation products, was measured at 3-h intervals during 24 hours in rats, adapted to lightrdark 12:12 h regimen in the course of the year. LPO in the liver, thymus and bone marrow oscillated rhythmically in the course of the day and year. Circadian oscillations in all tissues were two-peaked, with zeniths at various times of the light and dark parts of the day. In the liver and thymus, the highest mesors were found during the winter, in the bone marrow during the spring. The same holds for amplitude values, with the exception of the bone marrow which exhibited the highest values during the summer. The reason for the LPO oscillations is probably resulting from the changing ratio of pro- and anti-oxidative capacities in various tissues during the day and the year.
Physiologically, leptin concentration is controlled by circadian rhythm. However, in critically ill patients, circadian rhythm is disrupted. Thus we hypothesized that circadian leptin concentration changes are not preserved in critically ill patients. Ten consecutive critically ill heart failure patients with the clinical indication for mechanical ventilation and sedation were included into our study. Plasma leptin concentration was measured every 4 h during the first day (0-24 h) and during the third day (48-72 h) after admission. During the first day, there were significant leptin concentration changes (ANOVA, p<0.05), characterized by an increase in concentration by 44 % (16-58 %); p=0.02 around noon (10 am-2 pm) and then a decrease in concentration by 7 % (1-27 %); p=0.04 in the morning (2 am-6 am). In contrast, there was no significant change in leptin concentration during the third day after admission (ANOVA, p=0.79). Based on our preliminary results, we concluded that in critically ill heart failure patients, the circadian rhythm of plasma leptin concentration seems to be preserved during the first but not during the third day after admission., I. Cundrle Jr., P. Suk, V. Sramek, Z. Lacinova, M. Haluzik., and Obsahuje bibliografii