Effect of the antioxidant dibunol on the function of the adrenal cortex, the thyroid and the adenohypophysis in adult and old rats

The effect of a single antioxidant (dibunol-D) injection (100 mg/kg body weight) on the functional activity of adrenal cortex (AC), thyroid gland (TG) and tropic hormone production by adenohypophysis (AH) has been studied in old and adult rats. For 48 hours following D administration two-phase changes in adrenocorticotropic function of AH and steroidogenesis were detected in the AC: activation during the first hours was followed by suppression 24 hours later, and recovery 48 hours later. Thyrotropic AH function and thyroidogenesis were found to be decreased during the first hours of D effect. Thyroidogenesis recovery by the end of the first day was delayed as compared to the recovery of AH thyrotropic function. It is suggested that the mechanisms of D action are based on its effects mediated by changes in the functional activity of endocrine glands and associated with resetting of endocrine regulation of body functions.     

The spectral sensitivity of eye movements in response to light flashes inDaphnia magna

Summary The crustaceanDaphnia magna responds to a flash of light with a ventral rotation of its compound eye; this behavior is termed eye flick. We determined the spectral sensitivity for the threshold of eye flick in response to light flashes having three different spatial characteristics: (1) full-field, extending 180° from dorsal to ventral in the animal's field of view; (2) dorsal, 30° wide and located in the dorsal region of the visual field; (3) ventral, same as dorsal but located ventrally. All three stimuli extended 30° to the right and to the left of the animal's midplane. We found that spectral sensitivity varies with the spatial characteristics of the stimulus. For full-field illumination, the relative sensitivity was maximal at 527 nm and between 365 nm and 400 nm, with a significant local minimum at 420 nm. For the dorsal stimulus, the relative sensitivity was greatest at 400 nm, but also showed local maxima at 440 nm and 517 nm. For the ventral stimulus, the relative sensitivity maxima occurred at the same wavelengths as those for the full-field stimulus. At wavelengths of 570 nm and longer, the responses to both dorsal and ventral stimuli showed lower relative sensitivity than the full-field stimulus. No circadian or other periodic changes in threshold spectral sensitivity were observed under our experimental conditions. Animals which had their nauplius eyes removed by means of laser microsurgery had the same spectral sensitivity to full-field illumination as normal animals. Our results are discussed in terms of our current knowledge of the spectral classes of photoreceptors found in theDaphnia compound eye.     

The spread of somatosensory-evoked potentials within the nervous system

Four thalamic and cortical recordings were carried out in 5 patients. The thalamic-evoked potentials were typical and revealed a triphasic complex, but their latencies showed a relatively high standard deviation. They could be divided into two groups according to their latencies, both of which had low SD. These data suggested that there could be two types of latency of thalamic SEP, because the 4 patients' body sizes were very similar. More detailed surface, cortical and depth recordings are needed to resolve these questions.     

Measures of Dispersion with Weights Based on Ranks

The measures of dispersion for ungrouped data proposed by Gini and Lienert, which are defined as the mean of the ranges of pairs and triplets of n values, are generalised. A family of measures of dispersion emerges with weights based on ranks instead of the measurements themselves.     

Characterization of messenger RNA from epimastigotes and metacyclic trypomastigotes of Trypanosoma cruzi

The cell-free translation products of polyribosomal and post-polyribosomal mRNAs from the non-infective epimastigotes and the infective metacyclic trypomastigotes of the parasitic protozoan Trypanosoma cruzi were compared by two-dimensional polyacrylamide gel electrophoresis. The result show that although many polypeptides are conserved, quantitative and qualitative differences are observed between both differentiation stages. The results also indicate the existence of post-polyribosomal mRNAs in equilibrium with polyribosomal counterparts. The immunoprecipitation of the in vitro synthesized polypeptides with chagasic human serum and the serum raised against an 85-kDa glycoprotein (P2-WGA), potentially involved in the process of T. cruzi penetration into mammalian cells, shows that while the chagasic serum recognizes the same 72-kDa, 68-kDa and 46-kDa polypeptides in both differentiation stages, the anti-P2-WGA serum immunoprecipitates a single 48-kDa polypeptide from in vitro translation products of metacyclic trypomastigotes.     

Changes in glycosylated haemoglobin after poor control in insulin-dependent diabetics.

Glycosylated haemoglobin (HbA1) was measured in seven insulin-dependent diabetic patients before, during, and after a seven-day period of monitored poor control. There was considerable individual variation in the pattern and degree of change in HbA1 concentration induced by poor control and the time when it occurred. Greater increases in HbA1 were seen during the period of metabolic derangement than in the subsequent two months. More information is required before HbA1 estimations are widely used clinically to monitor control in individual diabetics.     

Comparison of optimization methods for fed-batch cultures of hybridoma cells

Two methods for the calculation of optimal trajectories for the input variables of a fed-batch culture of hybridoma cells are compared. It pointed out that a gradient method based on Pontryagins' minimum principle based yields a significant better performance with respect to computational effort and the calculated minimum than a dynamic programming approach which has been presented in a previous paper [1] as the most suitable method.