Purification and partial characterization of four proteins from human parotid saliva

Four proteins, which have been designated A, B, C and D, have been purified from human parotid saliva. These proteins are the major constituents of parotid saliva which migrate rapidly to the anode in polyacrylamide electrophoresis at pH9.5. Gel filtration and polyacrylamide electrophoresis were employed in the purification procedures. After purification all four preparations were tested for homogeneity by electrophoresis at pH2.8 and 9.5, by isoelectric focusing in the pH range 3-10, by immunodiffusion, and by sedimentation in the analytical ultracentrifuge. None of the proteins showed significant activity in assays for amylase, acid and alkaline phosphatase, protease, lysozyme, ribonuclease, peroxidase, beta-glucuronidase, beta-galactosidase, iron-binding activity and esterase. No cross-reactions were detected with antisera specific for lactoferrin and 15 serum proteins. All four proteins were rich in glutamic acid, proline and glycine and were lacking completely the sulphur-containing amino acids. Proteins A and C contained no threonine or tyrosine. Carbohydrate could be demonstrated only in protein A at a concentration of 4% of the total protein.     

Preparative thin-layer and column chromatography of prostaglandins

Chromatographic methods are used to identify various monounsaturated PGs (prostaglandins). TLC (thin-layer chromatography) and column chromatography are described in detail. These systems were developed specifically for separating epimers of PGE1 and PGF1, but they are useful in separating some of the known natural PGs as well. A table presents information on identification of the various PGs with neutral silica and acidic silica. The results of these laboratory experiments indicate that 1 ug-1g of PG can be purified by chromatographic methods with little or no loss due to irreversible adsorption or rearrangement if proper precautions and solvent systems are used. TLC seems to be useful in distinguishing diastereomers of PGs. Relative mobilities of the various hydroxy diastereomers are not changed by the solvent systems or by esterification.     

Electron microscopic observations on iron-labelled secondary lysosomes in renal tubules in mice

Summary Labelling of renal tubule cytosomes with electron dense iron granules can be attained by daily intramuscular injections to mice of an iron sorbitol citric-acid compound in a total of approximately 50 mg Fe⁺⁺⁺/100 g of body weight. The labelled cytosomes correspond to secondary lysosomes and represent heterolysosomes or ambilysosomes. The evidence suggests that tubule and lysosome function are undisturbed by the labelling procedure. The use of this method for fine structural studies of the interaction between secondary lysosomes and other cytoplasmic organelles and elements is indicated.Microbodies do not incorporate administered Fe⁺⁺⁺. The morphological observations support the opinion that these bodies are formed in specialized portions of the smooth surfaced endoplasmic reticulum of proximal tubule cells.Supported in part by grants from the Swedish Medical Research Council (Projects No. K 67-12x-1006-2, B 67-12x-1006-02K, K 68-12x-1006-03, and B 69-12x-1006-04A). The assistance of Miss Silwa Mengarelli and Miss Britt-Marie Pettersson is gratefully acknowledged.     

Application of a Theory for Circumnutations to Geotropic Movements

From a previously published theory (Israelsson and Johnsson 1967) for circumnutations in Helianthus annuus it is possible to predict the geotropical curvatures of the hypocotyls. This extension of the theory is given in the present paper and some geotropical experiments are performed and discussed. The agreement between the theory and the experiments has been verified in the case of gravitational stimulation during relatively short stimulation periods, in the case of continuous gravitational stimulation, etc. Restrictions in the proposed model are discussed.     

Ammoniten mit Kieferapparat und Radula aus Lias-Geschieben

Jaws and radula have been found in two adult microconch specimens of the Liassic ammonite speciesEleganticeras elegantulum (Young & Bird, 1828) from glacial drift boulders near Hamburg. They are more similar to those of recent dibranchiates than ofNautilus, the radula having seven longitudinal rows of teeth instead of thirteen in recentNautilus. Since bothOwens classification of the cephalopods into Dibranchiata and Tetrabranchiata according to the number of gills (which cannot be observed in fossil cephalopods) andSchwarz’ division into Ecto- and Endocochlia according to the (assumed) relative position of body and shell are rather unfortunate, the radula is suggested as a sound basis of classification. It is acceptable to paleo- as well as to neozoologists. As yet, the known evidence is sufficient for a twofold division only: Class Cephalopoda Subclass Lateradulata: Nautiloidea Subclass Angusteradulata: Ammonoidea Coleoidea