Neuronal transmission of hippocampal CA1 neurones is modulated by corticotropin-like intermediate lobe peptide [CLIP; ACTH(18–39)]

The study was conducted to test whether CLIP [ACTH(18–39)] influences the neuronal transmission and the induction of longterm potentiation (LTP) in the hippocampus. The population spike was recorded in the hippocampal CA1 region of freely moving rats before and after intracerebroventricular (ICV) administration of CLIP in comparison to ACTH and saline (controls). After infusion of CLIP, the population spike amplitude (PSA) rose to about 200% of baseline values. After reaching this level, it was impossible to induce a further increase of PSA by tetanization. However, if the stimulus intensity was reduced to a new baseline level, electrically induced LTP could be observed. There were no significant changes after infusion of ACTH. Our results indicate that the ICV administration of CLIP leads to an enhancement of excitability in the hippocampal CA1 region, which might be independent of LTP.     

Impact category ecotoxicity and valuation procedure

Within the methodology of LCA, the impact assessment of the impact category ecotoxicity and the valuation step for all categories still pose methodological challenges. A multi-tier approach is a pragmatic solution for the impact assessment of the impact category ecotoxicity. The screening tier only makes use of information concerning substance specific characteristics in order to derive both an identification of critical substances and a comparison of products. Within the detailed tier, critical substances are analyzed in more detail, but still without site-specific information on concentrations, time or region. Valuation combines scientific results with value judgements. Thus, it is not an objective process which can substitute decision making, but instead serves as a base for the interpretation of results. A pragmatic approach combines the results of the impact assessment with a normalization and weighting of the impact categories. Four approaches for deriving general weighting sets (population surveys, expert surveys using the delphi-technique, sustainable development, distance-to-target) are discussed and the first results obtained are presented.     

Development of granular sludge in the UASB-treatment model waste waters containing gelatine

Summary Protein containing model waste waters with 5 and 15 g/1 gelatine respectively were treated in UASB-process. The start-up was controlled pH-auxostatically and in both experiments the development of granular sludge with good sedimentation properties occured. The sludge flocks in the investigation with higher gelatine concentration and concomitantly higher NH ₄ ⁺ -concentration in the process were somewhat smaller and of lower density.     

A highly conserved sequence in H1 histone genes as an oligonucleotide hybridization probe: Isolation and sequence of a duck H1 gene

A 3.5-kb HindIII fragment of a histone gene cluster was isolated from a recombinant phage out of a duck genomic library. This DNA contains a duck H1 gene and its flanking sequences. The hybridization probe, which was used to screen for the H1 gene, had been designed on the basis of a comparative analysis of available H1 gene and protein data. Most H1 histones contain repeated motifs in their C-terminal domain, and these form part of an octapeptide (ser pro lys lys ala lys lys pro) that is highly conserved in many H1 histone proteins. A comparison of the duck H1 described here with two different published chicken H1 histone sequences reveals conservative amino acid exchanges at 22 (of 217 and 218, respectively) positions. The homology is maintained at the flanking sequences, and includes the putative H1 histone gene-specific signal structures and the established 3' stem and loop structures and the CAAGA box. The duck H1 gene and its flanking sequence have been found in identical arrangements in two recombinant bacteriophages, but minor sequence variations and genomic Southern blotting after HindIII digestion suggest that we have either isolated alleles of this genome segment or that the gene described may occur twice per haploid duck genome.     

Patterns of richness across forest beetle communities—A methodological comparison of observed and estimated species numbers

1. Species richness is a frequently used measure of biodiversity. The compilation of a complete species list is an often unattainable goal. Estimators of species richness have been developed to overcome this problem. While the use of these estimators is becoming increasingly popular, working with the observed number of species is still common practice.
2. To assess whether patterns of beetle communities based on observed numbers may be compared among each other, we compared patterns from observed and estimated numbers of species for beetle communities in the canopy of the Leipzig floodplain forest. These patterns were species richness and the number of shared species among three tree species and two canopy strata.
3. We tested the applicability of the asymptotic Chao1 estimator and the estimate provided by the nonasymptotic rarefaction–extrapolation method for all tree species and both upper canopy and lower canopy. In the majority of cases, the ranking patterns of species richness for host tree species and strata were the same for the observed and estimated number of species. The ranking patterns of the number of species shared among host tree species and strata, however, were significantly different between observed and estimated values.
4. Our results indicate that the observed number of species under‐represents species richness and the number of shared species. However, ranking comparisons of published patterns based on the number of observed species may be acceptable for species richness but likely not reliable for the number of shared species. Further studies are needed to corroborate this conclusion. We encourage to use estimators and to provide open access to data to allow comparative assessments.

     

Polarisationsoptisch-histochemische Untersuchungen zur Kongorotfärbung des Amyloid

Zusammenfassung Um den Färbemechanismus des Kongorot zu analysieren, wurden am Amyloid in Verbindung mit histochemischen Reaktionen polarisationsmikroskopisch das optische Vorzeichen der Doppelbrechung, der Farbstoffdichroismus und das Vorhandensein der anomalen grünen Polarisationsfarbe geprüft. Außer dem Dipolmoment der Amyloidfibrille ist ein orientiertes fibrillennahes Raumgitter zur Erzeugung des typischen polarisationsoptischen Farbeffektes notwendig. Zusätzlich hängt die Farbstoffakkumulation von der Fibrillendichte ab. Färbungen in wässerigen Kongorot-Lösungen unterscheiden sich von der Modifikation nach Puchtler durch eine initiale Bindung zwischen basischen Gruppen am Substrat und Sulfonsäureresten des Farbstoffes. Das Endergebnis, die parallel angelagerte Kongorotmizelle, ist in beiden Fällen gleich. Konsequenzen für die praktische Anwendung der Färbemethoden werden diskutiert.

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Polarization microscopic and histochemical investigations on the congo red-staining of amyloid

Summary For analysis of the staining mechanism of congo red the optical sign of birefringence, the stain dichroism and the occurrence of a green anomalous polarization colour were examined in amyloid utilizing a combination of histochemical reactions and polarization microscopy. In addition to the dipole moment of the statistically oriented amyloid fibrils there is necessary an oriented fibril-near spheric lattice to produce the specific polarization colour effect. Moreover the accumulation of dyes is depending on fibrillar density. Stainings in aqueous solutions of congo red are differing from the Puchtler-modification by an initial binding of basic groups of the substrate to sulphuric acid residues of the dye. In both cases unanimously the final result was found to be the parallel deposited congo red micelle at the amyloid fibril. The consequences for the use of staining techniques in practice are discussed.