Occurrence of Cladocera (Crustacea) in subterranean waters in Yugoslavia

Contrary to some localities in France and Spain, Cladocera occur in hypogean waters in Yugoslavia very sporadically. Beside the stygobitic species, Alona hercegovinae from caves and Alona smirnovi from interstitial waters, particularly some other Chydoridae seem to be suited for hypogean life. Chydorus sphaericus, reputed as one of the most euryoecious cladocerans, occurs also the deepest in interstitial waters as well as in caves. Other species, found in hypogean waters are Simocephalus vetulus, Ilyocryptus sordidus, Eurycercus lamellatus, Chydorus ovalis, Leydigia leydigi, Acroperus harpae and Biapertura affnis.     

Porewater chemistry of inorganic nitrogen compounds in the eastern Skagerrak (NE North Sea)

Porosity, Eh and interstitital nitrogen compounds profiles are given for four locations in the eastern Skagerrak. Sediments down to 30 cm depth, i.e. postindustrial in age, were analysed. The results together with a detailed age determination (²¹⁰Pb) suggest a high degree of both lateral and vertical variability as a result of local bottom topography and currents as well as event-controlled sedimentation processes.     

Citric acid production in chemically defined media by Aspergillus niger

Summary The effect of changing the composition of a chemically defined medium on citric acid production by Aspergillus niger was investigated. High and reproducible amounts of citric acid were obtained with deionized commercial sugar solutions, proper phosphate concentrations, low initial pH values and suitable amounts of copper as growth inhibiting agent.Comparison of high and low yielding process parameters showed that under high yielding conditions, (deionized sugar, Cu⁺⁺ addition) besides more citric acid, less mycelium and less mycelial lipids were formed; the consumption of sugar, nitrogen and phosphorus was related to the amount of biomass.Partly presented at the XII. International Congress of Microbiology; München, September 3–8, 1978     

Substance P-like immunoreactivity in the parietal eye visual system of the lizard Uta stansburiana

Summary We examined the parietal eye visual system of the iguanid lizard Uta stansburiana for the presence of substance P-like immunoreactivity by use of both immunofluorescence and peroxidase-antiperoxidase techniques. In the parietal eye no substance P-containing somata were found; however, its plexiform layer contained small (ca. 1 m diam) immunoreactive fibers. These fibers apparently originate outside the parietal eye. Immunoreactive fibers also were found in the parietal nerve, the dorsal sac, and the leptomeninx of the pineal gland. No labeled somata were observed in any of these regions in either normal or colchicine treated animals. Previously we demonstrated that a system of centrifugal fibers to the parietal eye originates from neurons in the dorsal sac (Engbretson et al. 1981). The apparent absence of substance P-containing neurons in the dorsal sac suggests that the substance P-containing fibers in the parietal eye are not the previously observed centrifugal fibers. The source of the substance P-containing fibers in the parietal eye is unknown. The pars dorsolateralis of the left medial habenular nucleus receives a dense substance P-positive projection. No such projection was seen in the right habenula. Simultaneous visualization of the terminals of ganglion cells of the parietal eye (labeled with orthograde intraaxonally transported horseradish peroxidase) and substance P-like immunofluorescence showed that the locus of habenular immunoreactivity is distinct from the projection field of the parietal eye. Thus the substance P-positive terminals in the habenula do not originate in the parietal eye. Transection of the parietal nerve confirmed this conclusion.     

Hapten-specific B cell repertoire probed by hybridoma technology: selection and characterization of representative clonotypes from the antibody-forming cell pool

In the course of this study, more than 3000 phthalate-specific antibody-forming cell hybrids were identified using the hybridoma technology. With the aid of a rapid screening assay and an extensive library of phthalate analogs, it was possible to assign selected hapten-specific clones to one of 11 distinct fine-specificity sets. This compartmentalization of the phthalate-specific hybridomas has made it possible to focus attention upon a single manageable portion of the phthalate-specific repertoire. Fourteen clones from a single fine-specificity set were selected for further immunochemical characterization. Five of these clones were found to secrete an antibody that was indistinguishable in isoelectric focusing. Affinity-purified, high-resolution anti-idiotype antibodies were prepared with specificity for the antibodies produced by one of these clones (i.e., 4C7). A major portion of the serologically defined private idiotype (4C7 IdI) was shown to be associated with the ligand-combining site. Our results indicate that the five clones that share a common spectrotype also express the 4C7 IdI. Two other independently derived clones from two distinct fusions also share this idiotype. The 4C7 IdI was also identified in affinity-purified anti-phthalate antibodies derived from a pool of phthalate-immune serum (conventional antibody) and from affinity-purified antibodies derived from a pool of serum from unimmunized BALB/c mice (natural antibody). The 4C7 IdI is thus considered to represent a repeating clonotype in the phthalate-specific repertoire of BALB/c mice, and will serve as one of several useful clonal markers that are being developed for studies of the mechanism regulating idiotype expression.     

Die Homologie des Perigons der Zingiberaceen Ein Beitrag zur Morphologie und Phylogenie des Monokotylen-Perigons

Nicolaia elatior is used as an example to demonstrate that the mucronate tepals ofZingiberaceae correspond to hypsophylls (bracts) consisting of a leaf sheath and a rudimentary Oberblatt (= leaf petiole + lamina) represented by the mucro. Evidence for this interpretation is furnished by all available criteria: leaf sequence (exhibiting a complete continuum of forms from foliage leaves over cata- and hypsophylls to the tepals), nervature, and ontogeny.The present conception is compared with the well-founded thesis ofLeinfellner that the perigone ofLiliaceae is derived from the androecium. The different morphological status of the perigone in both families is not regarded as the result of different phylogenetic origin, but as a manifestation of morphogenetic transgressions from one phyllome category to an adjacent one: In theLiliaceae the perigone is under a strong morphogenetic influence of the androecium, and therefore displays staminal characters, in theZingiberaceae it is under the dominating influence of the extrafloral region, and thus appears as a hypsophyllous structure. If this assumption of a morphologically oscillating perigone is correct, it will be fundamentally impossible to demonstrate unequivocally the phylogenetic origin of the monocotyledonous perigone.

Im wissenschaftlichen Werk Prof. Dr.Walter Leinfellners steht an erster Stelle die Morphologie der Blütenorgane. Als sein dankbarer Schüler möchte ich ihm aus Anlaß seines 70. Geburtstages die folgende Studie zu einem Thema zueignen, das ihn wie mich gleichermaßen angesprochen hat und schon Gegenstand der Forschungsarbeit des Jubilars war: die Homologie des Monokotylen-Perigons.     

Stimulation of differentiation of several murine embryonal carcinoma cell lines by retinoic acid

Retinoic acid stimulates several murine embryonal carcinoma (EC) cell lines, even those previously considered to be incapable of differentiating, to give rise to cell types distinguishable from the parental phenotype in morphology, production of plasminogen activator and surface protein properties. Retinoic acid promotes these changes over a range of low concentrations (10⁻⁹–10⁻⁵ M) which are generally non-toxic to the cells. The effects are clearly demonstrated when EC cells are aggregated prior to exposure to retinoic acid. It is concluded that the observed phenotypic alterations induced by retinoic acid reflect differentiation of the EC cells since non-EC cell characteristics are maintained by cloned cells several generations after retinoic acid is removed from the cultures. Our studies suggest that although retinoic acid stimulates the conversion of EC cells to differentiated derivatives, it does not influence the direction of differentiation. Furthermore, the effectiveness of retinoic acid in stimulating differentiation of EC cells from lines such as Nulli-SCC1 raises the question of whether true ‘nullipotent’ EC lines really exist.     

Lichenes novi quorum isotypi in fasciculo sexagesimo septimo collectionis “Lichenes selecti exsiccati” distribuentur

Diagnoses of the following 6 new lichen species are presented:Bacidia colchica Vězda sp. n.Buellia multispora Kalb etVězda sp.n.,Huilia circumnigrata Vězda sp.n.,Pyrenopsis sojakii Vězda sp.n.,Ramalina euxini Vězda sp.n. andStrangospora senecionis Lambinon etVězda sp.n. The isotypes will be distributed in fasc. 67 of the “Lichenes selecti exsiccati” (issued by the Botanical Institute, Czechoslovak Academy of Sciences, Pr?honice near Praha).