Electron microscopic demonstration of calcitonin in human medullary carcinoma of thyroid by the immuno gold staining method

In a human medullary carcinoma of thyroid gland containing calcitonin in light microscopic demonstration by the avidin biotin complex (ABC) method characteristic secretory granules were found electron microscopically in the cytoplasm of the tumour cells. They consisted in so-called type I granules (270 +/- 25 nm) and type II granules (135 +/- 17 nm). By the immuno gold staining (IGS) method the content of many secretory granules measuring 85-270 nm (152 +/- 18 nm) in diameter could be identified as calcitonin. These granules seemed to be predominantly of type II because of their nearly corresponding size and feature. The type I granules were less frequent in number and they showed no or little immunoreactivity. The results indicate that the IGS-method is practicable to demonstrate the ultrastructural localization of calcitonin and to identify clearly the nature of intracytoplasmic granules in electron microscopy.     

Studies on the (pro) insulin biosynthesis of islets of Langerhans of sand rats (Psammomys obesus).

By feeding a regular laboratory chow, sand rats (Psammomys obesus) from our breeding colony gained different body weights, though they received approximately the same quantity of calories. Sand rats, reaching a body weight above 160 g (group B) showed significantly increased blood glucose values in contrast to the animals with a body weight under 160 g (group A). Isolated pancreatic islets of these two groups of sand rats were incubated with [3H]-leucine to study the incorporation of this amino acid into proinsulin and insulin. The incorporation into proteins of pancreatic islets of sand rats of group B was stimulated by 0.45 mg and 3.0 mg/ml glucose. In group A there was no further stimulation from 0.45 mg to 3.0 mg/ml glucose. Insulin secretion could be stimulated by glucose in both groups, but the stimulation was stronger in group B than in group A.     

Species differences in biotransformation of 17α-cyanomethylestradiol 3-methyl ether

Following oral administration of 9,11- ³H-17α-cyano-methylestra-1,3,5(10)-triene-3,17-diol 3-methyl ether, urinary metabolites were studied in man, baboon, beagle dog, minipig and rat. The metabolite pattern revealed remarkable species differences, especially in quantitative respects. 17α-Cyanomethylestra-1,3,5(10)-triene-3,17-diol, 17α-cyanomethylestra-1,3,5(10)-triene-2,3,17-triol 2-methyl ether, 17α-hydroxymethylestra-1,3,5(10)-triene-3,17-diol and 17α-cyanomethylestra-1,3,5(10)-triene-3,16$\text{6}\text{5}$,17-triol were isolated as principal metabolites. In rat bile, a metabolite was tentatively identified as aγ-lactone of a 17α-carbozymethyl-16α-hydroxy compound.     

Substrate effects in tower loop reactors

Summary Hansenula polymorpha was cultivated in a bubble column loop bioreactor employing ethanol and/or glucose as substrates. By varying the substrate concentration, the cultivations were carried out in non-limited, substrate limited and oxygen transfer limited growth ranges. The influence of the transitions from one range to another on reactor performance (OTR,k _L a, a) and cell productivity () were investigated. When employing ethanol as a substrate, the concentration considerably influences the fluid dynamics, mass transfer phenomena and cell productivity. When employing glucose as a substrate, glucose repression occurs. At high glucose concentrations no transition into the oxygen transfer limited growth is possible. The ethanol produced during the glucose repression influences the fluid dynamics, mass transfer phenomena and productivity. With decreasing glucose concentration the glucose repression can be gradually eliminated.     

Foam behaviour of biological media

Summary A simple method was developed for evaluating foam stability. The influence of KCl and MgSO₄ on foam stability of bovine serum albumin foams was investigated. These salts increase foaminess, but diminish foam stability by the same degree. Thus there is little overall.     

Effect of sensory stimulation on the lamina V pyramidal neurons of the gyrus cinguli in the rat

Three groups of Wistar-rats were exposed to permanent noise (80 db) during different periods in their postnatal life: the first group was exposed starting from birth for a period of four weeks, the second one from birth up to nine weeks of age and the third group from the fifth up to the ninth week postnatal. A fourth group (control animals) was reared under normal laboratory conditions. After the experiments the brains were exposed to a modified GOLGI-method. In lamina-V-pyramids of the gyrus cinguli lightmicroscopical results: length, number and distribution of spines on the main apical dendrites and on the apical dendritic branches where evaluated. Main results: 1. Permanent noise during the early postnatal development phase of the brain of rats (from birth up to the fourth week of age) causes a statistically significant increase of apical spines. The spines-values are 20% above those of the control animals. 2. Permanent noise from birth up to the ninth week of age or applied only during the later postnatal period (from the fifth week up to the ninth week of age) does not significantly alterate the spines-value. 3. The results are estimated as a consequence of extreme environmental factors causing effects, comparable with an universal stress reaction. Conclusions were discussed in comparison to the results of other authors.