Schizonellin A and B,new glycolipids from Schizonella melanogramma

Two new glycolipids, schizonellin A and B, were isolated from cultures of the smut fungus Schizonella melanogramma. Their structures were elucidated by chemical degradation and spectroscopic methods. The schizonellins are active against Gram-positive bacteria, as well as against some Gram-negative bacteria and some fungi. DNA-, RNA- and protein-syntheses in Ehrlich carcinoma ascitic cells are inhibited simultaneously after addition of the schizonellins. Strong haemolytic action on bovine erythrocytes was observed.     

Die normalen Schwermetalle der Niere

Zusammenfassung 1. Anteile der in den Nieren vorhandenen Schwermetallspurenelemente Eisen, Zink, Kupfer, Cadmium, Blei lassen sich durch Schwefelwasserstoff in Sulfide umwandeln und durch physikalische Entwicklung sichtbar machen.2. Das Schwermetallaschenbild veranschaulicht besonders die Verteilung von Zink im Gewebe.3. Die nachweisbaren Anteile der Spurenelemente sind vorwiegend mobile Bestandteile des Gewebes. Sie liegen in den Deckzellen der Glomerula, an den Basalmembranen, in den Tubuluszellen und in den Kanälchenlichtungen. Ein schmaler Wall unter dem Bürstensaum der Hauptstückzellen bindet schwefelaffine Metalle: Zink, Kupfer, Blei, Quecksilber.4. Auf den Zink- und Kupfergehalt der Muskelzellen wird hingewiesen.5. Die Befunde werden diskutiert.Mit 15 TextabbildungenDurchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.Herrn Professor Dr.K. Thomas zum 75. Geburtstag.     

Inactivation of adenovirus and simian virus 40 tumorigenicity in hamsters by vaccine processing methods

The effectiveness of the adenovirus vaccine inactivation process in destroying the tumorigenic potential for hamsters of adenoviruses, simian virus 40 (SV-40), and adenovirus-SV-40 hybrids was studied. Baby hamsters injected with untreated virus and with samples subjected to the complete inactivation process and to portions of the process were observed for tumor development for periods in excess of 300 days. Over 20,000 hamsters were injected. From 1 to 7 hr of exposure to formaldehyde at a concentration of 0.031 m at 37 C was sufficient to destroy the tumorigenicity observed in the nontreated preparations. Since the inactivation process included 48 hr of exposure at 37 C to 0.031 m formaldehyde plus treatment with ultraviolet (UV) and with beta-propiolactone (BPL), it was concluded that the process has a large margin of safety. Adenovirus isolates free from tumorigenic potential are difficult, if not impossible, to obtain. Therefore, a proven inactivation process appears to provide the best assurance for obtaining adenovirus vaccines free from such potential. Data presented suggest that the tumorigenic property of the viruses studied might be independent of the infectivity of the preparation. The tumorigenic property was found to be highly susceptible to formaldehyde, but less sensitive to BPL or UV treatment. In contrast, treatment with UV or BPL decreased viral infectivity more readily than tumorigenicity. The three-stage inactivation process (formaldehyde, UV, and BPL) inactivated both tumorigenicity and infectivity.     

Malonate, Malonyl-Coenzyme A, and Acetyl-Coenzyme A in Developing Rat Brain

Abstract: Free malonate, malonyl-coenzyme A (malonyl-CoA), and acetyl-CoA were assayed in rat brain at developmental ages from the 20th day of gestation to 60 days of postnatal life. The determination of malonate was based on its conversion to malonyl-CoA and decarboxylation to acetyl-CoA by enzyme extracts from Pseudo-monas fluorescens. The resulting acetyl-CoA reacted with [4-¹⁴C]oxaloacetate to form [5-¹⁴C]citrate, which was isolated by TLC. Malonyl-CoA in perchloric acid extracts from brain was converted to acetyl-CoA by rat liver mitochondrial malonyl-CoA decarboxylase (EC 4.1.1.9). Acetyl-CoA derived from this step was assayed by a modified CoA-cycling procedure. Brain acetyl-CoA was also assayed by CoA cycling. Prenatal brain contained no free malonate but malonyl-CoA was present. The acetyl-CoA level was relatively high just prior to birth and declined slightly with growth. Malonate concentrations after birth rose rapidly to reach 192 nmol/g wet weight at 60 days. Adult levels for malonyl-CoA and acetyl-CoA were 1.83 and 1.90 nmol/g wet weight, respectively. The origin and natural role of free malonate in brain are not known but deacylation of malonyl-CoA by reversal of the malonyl-CoA synthetase reaction is postulated. Rat liver and kidney also contain substantial concentrations of free malonate.     

Induction of mammalian cell death by simple shear and extensional flows

In this work we investigated whether the type of shear flow, to which cells are exposed, influences the initiation of cell death. It is shown that mammalian cells, indeed, distinguish between discrete types of flow and respond differently. Two flow devices were employed to impose accurate hydrodynamic flow fields: uniform steady simple shear flow and oscillating extensional flow. To distinguish between necrotic and apoptotic cell death, fluorescence activated cell sorting and the release of DNA in the culture supernatant was used. Results show that Chinese Hamster Ovaries and Human Embryonic Kidney cells will enter the apoptotic pathway when subjected to low levels of hydrodynamic stress (around 2.0 Pa) in oscillating, extensional flow. In contrast, necrotic death prevails when the cells are exposed to hydrodynamic stresses around 1.0 Pa in simple shear flow or around 500 Pa in extensional flow. These threshold values at which cells enter the respective death pathway should be avoided when culturing cells for recombinant protein production to enhance culture longevity and productivity. Biotechnol. Bioeng. 2009; 104: 360–370 © 2009 Wiley Periodicals, Inc.     

Population genetic structure of Cydia pomonella: a review and case study comparing spatiotemporal variation

Analysis of population genetic structure is a key aspect to understand insect pest population dynamics in agricultural scenarios. Here the role of geography, hosts and time on the population genetic structure of codling moth Cydia pomonella (Linnaeus) (Lep., Tortricidae) populations is described. Temporal variation was examined in two French orchards among each of three adult flights during two successive years. Analyses were conducted using two insecticide resistance markers (variation at the sodium channel gene and enzymatic activity of cytochrome P450 oxidases) and three microsatellite loci. Levels of genetic variation among temporal populations were not significant based on variation in the sodium channel gene and microsatellite loci. However, P450 oxidase activity differed significantly during both flights and years, decreasing during the three flights of the first year and increasing during the second. These results suggest that phytosanitary measures are among the factors shaping the genetic structure of C. pomonella populations over temporal and geographical scales. We discuss the relative importance of natural and passive dispersal related to anthropogenic activities affecting C. pomonella population genetics and highlight population genetic research needs in order to design more efficient pest management practices.     

Real-time dialogue between experimenters and dreamers during REM sleep

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Potential of Biowaste from the Food Industry as a Biomass Resource

The importance of biomass as a resource for energy production or as a chemical feedstock will increase significantly in the next decades. The amounts of biomass that can be used for non‐food purposes however will be limited and its use will compete with other claims like food and feed production. In order to minimize such food‐feed‐fuel conflicts it is necessary to integrate all kinds of biowaste into a biomass economy. The food industry in particular might be a good candidate for assessment, since it produces inevitably large amounts of biogenic residues each year. The possibilities to use food processing residues for non‐food purposes like bioenergy, biomaterial production, chemical feedstock or as animal feed are therefore discussed in more detail in this paper. It is shown that food processing residues represent a small but valuable biomass fraction that can be exploited in numerous ways. The most promising approach appears to be to design new microbial bioconversion processes as part of more complex biorefinery concepts.