Untersuchungen über die Wirkung des Cyanamids im Kalkstickstoff auf pathogene und nichtpathogene Mikroorganismen des Bodens

Ohne Zusammenfassung     

Zum Feinbau der koshewnikowschen drüse bei der honigbiene Apis mellifica (Insecta,Hymenoptera)

An electron microscopic examination of the KOSHEWNIKOW gland of the honeybee showed that the origin of the draining ductule extended into the gland cell through an invagination without actual cytoplasmic connection being made. The structure of the wall of the dendritic apical ramifications of the duct cell is very loose where it is in juxtaposition to the microvilli of the wall of the gland cell. In contrast, the rest of the duct wall is very dense.

---

---

Gekürzte Dissertation der Fakultät für Chemie, Biologic, Geologic und Mineralogio der Technischen Hochschule Darmstadt; D I7. Danken möchte ich meinem verstorbenen Lehrer, Herrn Prof. Dr. W. Luther, Herrn Prof. Dr. D. B. E. Magnus and ganz besonders Herrn Prof. Dr. K. E. Wohlfarth-Bottermann für seine hilfsbereite Beratung in Fragen der Elektronenmikroskopie.     

The HYP2 gene of Saccharomyces cerevisiae is essential for aerobic growth: characterization of different isoforms of the hypusine-containing protein Hyp2p and analysis of gene disruption mutants

In Saccharomyces cerevisiae, hypusine-containing proteins are encoded by two closely related genes, HYP1 and HYP2, which are regulated reciprocally by oxygen and heme. We have purified the aerobically expressed hypusine-containing proteins from yeast. The three proteins detected (two isoforms, which differ in their pI values, and a degradation product thereof, lacking the N-terminal 10 amino acid residues) are all encoded by HYP2. The N-terminus of both isoforms is formed by acetylation of a serine residue after cleavage of the first methionine. Cells mutant for hyp2 are unable to grow aerobically. However, under anaerobic conditions these mutants display no obvious phenotype, presumably because the strictly anaerobically expressed HYPI gene product (Hyp1p) is present. This implies that Hyp1p and Hyp2p fulfill very similar functions. In fact, Hyp1p can substitute for Hyp2p under aerobic conditions, when expressed under the control of the GAL1 promoter in hyp2 mutant cells.Abbreviations HYP1 and HYP2 S. cerevisiae genes encoding hypusine-containing protein Hyplp and Hyp2p, respectively     

How long was the Younger Dryas? Preliminary evidence from annually laminated sediments of Soppensee (Switzerland)

Despite extensive AMS-¹⁴C dating series on Late-glacial terrestrial plant remains, a precise estimate of the duration of the Younger Dryas biozone (sensu Ammann & Lotter, 1989) is hampered by the occurrence of a period of constant ¹⁴C-age at 10 000 yr B.P. However, varve counts at Soppensee suggest that the Younger Dryas biozone comprises approx. 680–720 varves, and that the phase of constant radiocarbon age includes between 270–310 varves.     

Minimal water activity for enterotoxin A production and growth of Staphylococcus aureus.

The minimal water activity (alphaw) for growth was correlated with enterotoxin A formation by two strains of Staphylococcus aureus in a salt mixture broth. Within 7 days at 30 degrees C both strains grew and formed enterotoxin A minimally between alphaw 0.864 and 0.867, but at 25 degrees C, the minimal alphaw for both activities was increased to between 0.870 and 0.887 after a 2-week incubation.     

A simple and inexpensive method for investigating microbiological,enzymatic, or inorganic catalysis using standard histology and microbiology laboratory equipment: assembly,mass transfer properties,hydrodynamic conditions and evaluation

We introduce a generic, simple, and inexpensive method for performing microbiological, enzymatic, or inorganic catalysis with solids using standard histology and microbiology laboratory equipment. Histology cassettes were used to standardize hydrodynamic conditions and to protect the catalysts and their solid supports. Histology cassettes have the following advantages: they are readily available, inexpensive, solvent and acid resistant, automatable, and the slots in the cassette walls allow liquid to circulate freely. Standard Erlenmeyer flasks were used as reaction vessels. We developed a new camera to observe the movement and position of the histology cassettes as well as the liquid in the Erlenmeyer flasks. The camera produces a stable image of the rotating liquid in the Erlenmeyer flask. This visualization method revealed that in a 250?ml Erlenmeyer flask, stable operating conditions are achieved at a shaking frequency of 300?rpm and a fill volume of 30?ml. In vessels with vertical walls, such as beakers or laboratory bottles, the movement of the histology cassette is not reproducible. Mass transfer characterization using a biological model system and the chemical sulfite-oxidation method revealed that the histology cassette does not influence gas-liquid mass transfer.     

Effects of Erythropoietin in Murine-Induced Pluripotent Cell-Derived Panneural Progenitor Cells

Induced cell fate changes by reprogramming of somatic cells offers an efficient strategy to generate autologous pluripotent stem (iPS) cells from any adult cell type. The potential of iPS cells to differentiate into various cell types is well established, however the efficiency to produce functional neurons from iPS cells remains modest. Here, we generated panneural progenitor cells (pNPCs) from mouse iPS cells and investigated the effect of the neurotrophic growth factor erythropoietin (EPO) on their survival, proliferation and neurodifferentiation. Under neural differentiation conditions, iPS-derived pNPCs gave rise to microtubule-associated protein-2 positive neuronlike cells (34% to 43%) and platelet-derived growth factor receptor positive oligodendrocytelike cells (21% to 25%) while less than 1% of the cells expressed the astrocytic marker glial fibrillary acidic protein. Neuronlike cells generated action potentials and developed active presynaptic terminals. The pNPCs expressed EPO receptor (EPOR) mRNA and displayed functional EPOR signaling. In proliferating cultures, EPO (0.1–3 U/mL) slightly improved pNPC survival but reduced cell proliferation and neurosphere formation in a concentration-dependent manner. In differentiating cultures EPO facilitated neurodifferentiation as assessed by the increased number of β-III-tubulin positive neurons. Our results show that EPO inhibits iPS pNPC self-renewal and promotes neurogenesis.     

TNFα-Mediated Liver Destruction by Kupffer Cells and Ly6Chi Monocytes during Entamoeba histolytica Infection

Amebic liver abscess (ALA) is a focal destruction of liver tissue due to infection by the protozoan parasite Entamoeba histolytica (E. histolytica). Host tissue damage is attributed mainly to parasite pathogenicity factors, but massive early accumulation of mononuclear cells, including neutrophils, inflammatory monocytes and macrophages, at the site of infection raises the question of whether these cells also contribute to tissue damage. Using highly selective depletion strategies and cell-specific knockout mice, the relative contribution of innate immune cell populations to liver destruction during amebic infection was investigated. Neutrophils were not required for amebic infection nor did they appear to be substantially involved in tissue damage. In contrast, Kupffer cells and inflammatory monocytes contributed substantially to liver destruction during ALA, and tissue damage was mediated primarily by TNFα. These data indicate that besides direct antiparasitic drugs, modulating innate immune responses may potentially be beneficial in limiting ALA pathogenesis.     

Objectively Measured Physical Activity in European Adults: Cross-Sectional Findings from the Food4Me Study

Background

Comparisons of objectively measured physical activity (PA) between residents of European countries measured concurrently with the same protocol are lacking. We aimed to compare PA between the seven European countries involved in the Food4Me Study, using accelerometer data collected remotely via the Internet.

Methods

Of the 1607 participants recruited, 1287 (539 men and 748 women) provided at least 3 weekdays and 2 weekend days of valid accelerometer data (TracmorD) at baseline and were included in the present analyses.

Results

Men were significantly more active than women (physical activity level = 1.74 vs. 1.70, p < 0.001). Time spent in light PA and moderate PA differed significantly between countries but only for women. Adherence to the World Health Organization recommendation to accumulate at least 150 min of moderate-equivalent PA weekly was similar between countries for men (range: 54–65%) but differed significantly between countries for women (range: 26–49%). Prevalence estimates decreased substantially for men and women in all seven countries when PA guidelines were defined as achieving 30 min of moderate and vigorous PA per day.

Conclusions

We were able to obtain valid accelerometer data in real time via the Internet from 80% of participants. Although our estimates are higher compared with data from Sweden, Norway, Portugal and the US, there is room for improvement in PA for all countries involved in the Food4Me Study.