Heterogeneity of tubulin epitopes in mouse fetal tissues

Summary A panel of six monoclonal antibodies against alpha (TU-01, TU-03, TU-04, TU-05, TU-09) or beta (TU-13) subunits of tubulin was used to study expression of tubulin epitopes in 14-day-old mouse embryos. Specificity of antibodies was confirmed by immunoblotting experiments. Monoclonal antibodies TU-01, TU-09 and TU-13, like the polyclonal antibody reacted essentially with all tissues, whereas other antibodies displayed differential reactivity. Most notably, TU-03 reacted very strongly with simple epithelia and basal layer of stratified epithelial layers. TU-04 recognized maturation related changes in spinal cord. Reactivity of TU-05 was restricted to central nervous system and peripheral nerves.Present results document immunohistochemical heterogeneity of tubulin in fetal tissues and suggest the existence of maturation and tissue specific epitopes of tubulin in developing organs.     

An indirect method for quantitation of cellular zinc content of timm-stained cerebellar samples by energy dispersive X-ray microanalysis

Summary The absolute concentration of zinc in the Purkinje cells of the rat cerebellum was determined by means of energy dispersive X-ray microanalysis (EDAX). Gelatine blocks with known zinc concentrations were stained by Timm's sulphide-silver method, and their silver concentrations were measured by EDAX. A linear correlation was found between the zinc and silver concentrations and this linear function was used as a quantitative calibration for evaluation of sulphide-silver staining, after perfusion with sodium-sulphide solution, fixation with glutaraldehyde, cryostat sectioning and staining of cerebellar samples in Timm's reagent.     

Histochemistry of proteases in ependyma,choroid plexus and leptomeninges

Summary Aminopeptidase M (APM), aminopeptidase A (APA), dipeptidyl peptidase IV (DPP IV) and -glutamyl transferase (GGT) were demonstrated histochemically in cryostat sections of the rat brain to show the reaction pattern of ependyma, choroid plexus and leptomeninges. GGT was only demonstrable in the cell membranes of ependymal cells and in the leptomeninges; however, APA, APM and DAP IV showed a variable degree of activity in the capillary endothelium of the choroid plexus as well as in the leptomeninges. On the basis of these results, it is postulated that peptides in the cerebrospinal fluid can be cleaved extraventricularly by the enzymes demonstrated in the leptomeninges.Dedicated to Professor Dr. T.H. Schiebler on the occasion of his 65th birthday     

A comparison of the drying of chymotrypsin bound to bead cellulose by lyophilisation and in air at 25 to 70°C

Summary The effect was studied of the method of drying chymotrypsin attached to bead cellulose on its chemical and physical characteristics. These characteristics are not deteriorated when replacing the commonly used lyophilisation by fluid drying in the air stream. The preparations saved essentially the same proteolytic activity as well as stability even when increasing the drying air temperature to 70°C.     

Microfungus-yeast mixed cultures in the degradation of amylaceous wastes. II: An experimental design for optimization of yeast production

Summary By means of an experimental factorial design the role of several culture conditions is described and its values determined for the maximum yeast production in mixed cultures ofAspergillus oryzae andRhodotorula glutinis.     

A Comparative Study of the Storage Carbohydrate Granules from Euglena (Euglenida) and Pavlova (Prymnesiida)1,2

ABSTRACT The storage carbohydrate granules from Euglena and Pavlova were compared by light and electron microscopy. Freezeetch studies demonstrated that while both types of granules are crystalline, they have different structures. The elemental microfibril of the euglenoid granule measures 4 nm, and the elemental striation of the granule from Pavlova is 22 nm. The granules each have a unique X-ray diffraction pattern. The storage carbohydrate granules from Pavlova are not the same as paramyton, and the term “paramylon” should be reserved for the euglenoid storage carbohydrate.     

Das Überdauern von Pollenkörnern an reifen Getreidesamen: Beitrag zur Präzisierung einer Interpretation der pollenanalytischen Ergebnisse

In order to improve the interpretation of the results of pollen analyses concerning mediaeval anthropogenous sediments a set of recent seeds of the principal cereals was pollenanalytically elaborated. The aim was to find out whether pollen grains can be preserved on mature seeds. The pollen spectra obtained from the material of mediaeval anthropogenous sediments include, in most cases, a large amount of pollen of certain plants including cereals. It is suggested that part of the pollen spectra from anthropogenous sediments need not come from air transport, i.e. from the surrounding vegetation; it could get into waste pits in another way. Above all, some foodstuffs were considered to be the sources of pollen grains. The origin of some grains coming from honey and from plant infusions has, at least partly, been demonstrated (Jankovská 1987). As the next step, attention was paid to other products, mainly those of cereals. An experimental pollen analysis of recent seeds of selected cereals showed that pollen grains are preserved on their surface, often in high concentrations. This is due, above all, to the cleistogamy of most cereals. The highest values of pollen grains have so far been found inAvena sativa andPanicum milliaceum. Triticum aestivum andHordeum vulgare showed lower values of pollen grains. The lowest amounts were found in heterogamousSecale cereale. Simultaneously, the pollen of plants growing in a neighbourhood, above all the pollen of field weeds, was found sticking to the seeds.     

Selected chromosome counts of the Czechoslovak flora I

Chromosome numbers of the following nine taxa of the Czechoslovak flora are given:Atriplex rosea L.,Cardamine resedifolia L.,Groenlandia densa (L.)Fourr.,Isoëtes lacustris L.,Lysimachia nemorum L.,Parnassia palustris L.,Phelipanche caesia (Rchb.) Soják,Rumex patientia L. subsp.patientia andSymphytum officinale L. s. str. A new chromosome number of 2n=80 is reported forRumex patientia L. subsp.patientia. Chromosome numbers of another five taxa are first reported from Czechoslovakia. Each of the ascertained chromosome counts is discussed with respect to hitherto known reports.