Effect of Emblica officinalis (Gaertn) on lens regeneration in the frog, Rana cyanophlyctis (Schneider).

Emblica officinalis (Amla) accelerated cell proliferation and dedifferentiation of pigmented epithelial cells of dorsal iris and consequently induced lens regeneration in R. cyanophlyctis. Further it enhanced the percentage of lens regeneration not only in young tadpoles but also is adult frogs. Lens regeneration ability declined with the age of animals in both control as well as treated groups.

Age related modulation of circadian time structure of blood, plasma and tissue variables in male domestic fowls.

To study modulation of circadian time structure of 11 blood, plasma and tissue variables in male domestic fowls, as a function of age, three experiments were made in one-day-old fowls (72) standardized by 12L:12D. In the first experiment, at 6 week age, 24 birds were killed by decapitation, four each at six different circadian stages (2, 6, 10, 14, 18 and 22 hr after light onset, HALO). Equal number of birds were killed at similar circadian stages at the age of 12 and 18 week in the second and the third experiments, respectively. Age affected both, the circadian patterns and the mesors (24 hr mean values). The circadian pattern included amplitude (half of the total extent of variation) and acrophase (estimated time of peak) for each variable. The results clearly suggest that the pattern of circadian rhythm may vary as a function of age of the bird.

Circadian features of carbohydrate metabolism in domestic fowls exposed to weekly 120 degree-shifts of synchronizer schedule.

Effects of weekly 8 hr advance- or delay-shifts on the circadian rhythm of plasma glucose, liver glycogen and muscle glycogen in male domestic fowls, beginning at about 3 days of age, were examined. Circadian rhythm in the aforesaid indices of carbohydrate metabolism in control birds was also studied. Blood and tissue samples were collected from birds in all the three groups at 4 hr intervals over a single 24 hr time scale both at 6th and 12th week of age. Plasma glucose and glycogen content in the tissues were determined by employing standard techniques. Cosinor rhythmometry was used for analyzing time series data. In general, a statistically significant circadian rhythm was documented for all the three indices in control and advance-schedule birds, irrespective of age. In contrast, in delay-schedule birds, statistically significant circadian rhythm could not be detected, excluding in muscle glycogen at 12th week of age. The poor growth rate in the delay-schedule birds could be imputed to the disappearance of circadian rhythm in the indices of carbohydrate metabolism.

Desynchronization of oral temperature, pulse and performance circadian rhythms in shift working Indian nurses.

Circadian time structure in shift working Indian nurses was studied. In shift workers desynchronization between circadian rhythms in different physiological variables was observed. Circadian amplitudes of oral temperature, pulse and random add speed rhythms decreased significantly in shift workers as compared to control subjects. Circadian mesors of performance rhythms increased significantly in shift workers indicating that the time taken by them was more for performing the tasks. It can be concluded that the subjects studied herein are intolerant to shift work and amplitude decrement may be considered as a chronobiologic index to determine the tolerance of individual workers to shift work.

Effects of zeitgeber shifts on gonadal function in male domestic fowls.

Effects of shifting light dark (LD) schedule of 8 hr/week on comb height and gonadal development were investigated in male domestic fowls. Three-day-old birds were exposed to repeated delay (westward shift) or repeated advancement (eastward shift) of the LD schedule at weekly intervals till they attained the age of 20 weeks. Control birds were held in fixed LD 12:12 hr light/dark schedule. Comb height was monitored at weekly intervals beginning at the age of 7 weeks. At 12th, 16th and 20th week 5 birds from each schedule were sacrificed and gonadal volume was recorded. Results indicate that comb and gonadal growth were significantly higher in advance-schedule birds when compared with control and delay-schedule birds. Histologically, testes of advance-schedule birds were more active when compared with those of control and delay-schedule birds. It appears that the eastward shifts of the synchronizer schedule may exert stimulatory influence on gonads.

Effects of repeated eastward and westward synchronizer phase-shifts on growth, blood morphology and biochemical variables in male domestic fowls.

The effects of repeated synchronizer phase-shifts on growth (increment in body weight), blood morphology and growth related biochemical variables in 3-day-old juvenile male chicks were evaluated till they become 20 weeks old. The control birds were kept under a fixed LD 12:12 light schedule throughout, while the LD 12:12 regimen of experimental birds was shifted weekly either by delaying (westward shift) or by advancing (eastward shift) the time of light onset by 8 hr. The rate of growth was more in fowls which were exposed to repeated advancement of synchronizer schedule than the controls and those exposed to westward shifts of the synchronizer schedule. Hematological indices, viz., hemoglobin concentration, number of circulating erythrocytes, hematocrit and biochemical variables, such as concentration of glucose and protein in plasma; glycogen, protein and lipid in liver; and muscle tissues were significantly more in chicks exposed to repeated eastward shifts, when compared with the control birds (LD 12:12). It is suggested that the eastward shift of the synchronizer may be beneficial for the poultry birds.