Gefangene in deutschem und sowjetischem Gewahrsam 1941 - 1956: Dimensionen und Definitionen

Aus der Einleitung S. 7: „Anders als in den Kriegen vergangener Epochen hat der Zweite Weltkrieg im Zeichen der totalen Kriegsführung des 20. Jahrhunderts die Grenzen zwischen dem Militär und der Zivilbevölkerung endgültig verwischt. Das gilt für die unmittelbare Kriegsführung wie für die Kriegsfolgen, zu denen neben Deportation, Flucht und Vertreibung nicht zuletzt die Gefangenschaft zählt. Gefangenschaft war ein millionenfaches Schicksal, das in den Jahren nach 1939 Soldaten wie Zivilisten traf – insbesondere in dem 1941 von Hitler begonnenen, rassenideologisch motivierten Angriffs- und Vernichtungskrieges des Deutschen Reiches gegen die Sowjetunion...

Synergy of the antibiotic colistin with echinocandin antifungals in Candida species.

International audienceOBJECTIVES: Candida albicans is the most prevalent fungal pathogen of humans, causing a wide range of infections from harmless superficial to severe systemic infections. Improvement of the antifungal arsenal is needed since existing antifungals can be associated with limited efficacy, toxicity and antifungal resistance. Here we aimed to identify compounds that act synergistically with echinocandin antifungals and that could contribute to a faster reduction of the fungal burden. METHODS: A total of 38 758 compounds were tested for their ability to act synergistically with aminocandin, a β-1,3-glucan synthase inhibitor of the echinocandin family of antifungals. The synergy between echinocandins and an identified hit was studied with chemogenomic screens and testing of individual Saccharomyces cerevisiae and C. albicans mutant strains. RESULTS: We found that colistin, an antibiotic that targets membranes in Gram-negative bacteria, is synergistic with drugs of the echinocandin family against all Candida species tested. The combination of colistin and aminocandin led to faster and increased permeabilization of C. albicans cells than either colistin or aminocandin alone. Echinocandin susceptibility was a prerequisite to be able to observe the synergy. A large-scale screen for genes involved in natural resistance of yeast cells to low doses of the drugs, alone or in combination, identified efficient sphingolipid and chitin biosynthesis as necessary to protect S. cerevisiae and C. albicans cells against the antifungal combination. CONCLUSIONS: These results suggest that echinocandin-mediated weakening of the cell wall facilitates colistin targeting of fungal membranes, which in turn reinforces the antifungal activity of echinocandins

The NDR/LATS Kinase Cbk1 Controls the Activity of the Transcriptional Regulator Bcr1 during Biofilm Formation in Candida albicans

In nature, many microorganisms form specialized complex, multicellular, surface-attached communities called biofilms. These communities play critical roles in microbial pathogenesis. The fungal pathogen Candida albicans is associated with catheter-based infections due to its ability to establish biofilms. The transcription factor Bcr1 is a master regulator of C. albicans biofilm development, although the full extent of its regulation remains unknown. Here, we report that Bcr1 is a phosphoprotein that physically interacts with the NDR kinase Cbk1 and undergoes Cbk1-dependent phosphorylation. Mutating the two putative Cbk1 phosphoacceptor residues in Bcr1 to alanine markedly impaired Bcr1 function during biofilm formation and virulence in a mouse model of disseminated candidiasis. Cells lacking Cbk1, or any of its upstream activators, also had reduced biofilm development. Notably, mutating the two putative Cbk1 phosphoacceptor residues in Bcr1 to glutamate in cbk1Δ cells upregulated the transcription of Bcr1-dependent genes and partially rescued the biofilm defects of a cbk1Δ strain. Therefore, our data uncovered a novel role of the NDR/LATS kinase Cbk1 in the regulation of biofilm development through the control of Bcr1

Interfering with Glycolysis Causes Sir2-Dependent Hyper-Recombination of Saccharomyces cerevisiae Plasmids

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key metabolic regulator implicated in a variety of cellular processes. It functions as a glycolytic enzyme, a protein kinase, and a metabolic switch under oxidative stress. Its enzymatic inactivation causes a major shift in the primary carbohydrate flux. Furthermore, the protein is implicated in regulating transcription, ER-to-Golgi transport, and apoptosis. We found that Saccharomyces cerevisiae cells null for all GAPDH paralogues (Tdh1, Tdh2, and Tdh3) survived the counter-selection of a GAPDH–encoding plasmid when the NAD+ metabolizing deacetylase Sir2 was overexpressed. This phenotype required a fully functional copy of SIR2 and resulted from hyper-recombination between S. cerevisiae plasmids. In the wild-type background, GAPDH overexpression increased the plasmid recombination rate in a growth-condition dependent manner. We conclude that GAPDH influences yeast episome stability via Sir2 and propose a model for the interplay of Sir2, GAPDH, and the glycolytic flux

Candida albicans AGE3, the Ortholog of the S. cerevisiae ARF-GAP-Encoding Gene GCS1, Is Required for Hyphal Growth and Drug Resistance

BACKGROUND: Hyphal growth and multidrug resistance of C. albicans are important features for virulence and antifungal therapy of this pathogenic fungus. METHODOLOGY/PRINCIPAL FINDINGS: Here we show by phenotypic complementation analysis that the C. albicans gene AGE3 is the functional ortholog of the yeast ARF-GAP-encoding gene GCS1. The finding that the gene is required for efficient endocytosis points to an important functional role of Age3p in endosomal compartments. Most C. albicans age3Delta mutant cells which grew as cell clusters under yeast growth conditions showed defects in filamentation under different hyphal growth conditions and were almost completely disabled for invasive filamentous growth. Under hyphal growth conditions only a fraction of age3Delta cells shows a wild-type-like polarization pattern of the actin cytoskeleton and lipid rafts. Moreover, age3Delta cells were highly susceptible to several unrelated toxic compounds including antifungal azole drugs. Irrespective of the AGE3 genotype, C-terminal fusions of GFP to the drug efflux pumps Cdr1p and Mdr1p were predominantly localized in the plasma membrane. Moreover, the plasma membranes of wild-type and age3Delta mutant cells contained similar amounts of Cdr1p, Cdr2p and Mdr1p. CONCLUSIONS/SIGNIFICANCE: The results indicate that the defect in sustaining filament elongation is probably caused by the failure of age3Delta cells to polarize the actin cytoskeleton and possibly of inefficient endocytosis. The high susceptibility of age3Delta cells to azoles is not caused by inefficient transport of efflux pumps to the cell membrane. A possible role of a vacuolar defect of age3Delta cells in drug susceptibility is proposed and discussed. In conclusion, our study shows that the ARF-GAP Age3p is required for hyphal growth which is an important virulence factor of C. albicans and essential for detoxification of azole drugs which are routinely used for antifungal therapy. Thus, it represents a promising antifungal drug target

Peanut‐induced anaphylaxis in children and adolescents: Data from the European Anaphylaxis Registry

Background Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%-1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents. Methods Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre. Results 3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004). Conclusions The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition

Gefangene in deutschem und sowjetischem Gewahrsam 1941 - 1956: Dimensionen und Definitionen

Aus der Einleitung S. 7: „Anders als in den Kriegen vergangener Epochen hat der Zweite Weltkrieg im Zeichen der totalen Kriegsführung des 20. Jahrhunderts die Grenzen zwischen dem Militär und der Zivilbevölkerung endgültig verwischt. Das gilt für die unmittelbare Kriegsführung wie für die Kriegsfolgen, zu denen neben Deportation, Flucht und Vertreibung nicht zuletzt die Gefangenschaft zählt. Gefangenschaft war ein millionenfaches Schicksal, das in den Jahren nach 1939 Soldaten wie Zivilisten traf – insbesondere in dem 1941 von Hitler begonnenen, rassenideologisch motivierten Angriffs- und Vernichtungskrieges des Deutschen Reiches gegen die Sowjetunion...

Gefangene in deutschem und sowjetischem Gewahrsam 1941 - 1956: Dimensionen und Definitionen

Aus der Einleitung S. 7: „Anders als in den Kriegen vergangener Epochen hat der Zweite Weltkrieg im Zeichen der totalen Kriegsführung des 20. Jahrhunderts die Grenzen zwischen dem Militär und der Zivilbevölkerung endgültig verwischt. Das gilt für die unmittelbare Kriegsführung wie für die Kriegsfolgen, zu denen neben Deportation, Flucht und Vertreibung nicht zuletzt die Gefangenschaft zählt. Gefangenschaft war ein millionenfaches Schicksal, das in den Jahren nach 1939 Soldaten wie Zivilisten traf – insbesondere in dem 1941 von Hitler begonnenen, rassenideologisch motivierten Angriffs- und Vernichtungskrieges des Deutschen Reiches gegen die Sowjetunion...

Metabolic interplay of GAPDH and Sir2.

<p>GAPDH catalyzes the oxidation of NADH: it generates NAD⁺ in close proximity to Sir2. Under conditions with high glycolytic flux, higher amounts of glyceraldehyde-3-phosphate (gly-3-P) are produced, driving the backward reaction. In this case, GAPDH reduces more NAD⁺ to NADH and inhibits the deacetylation reaction by depleting NAD⁺; NAD⁺ is a limiting factor for the Sirtuins to catalyze the formation of O-acetyl-ADP-ribose (AADPR) via the transfer of acetyl groups.</p

Δ<i>tdh1</i>Δ<i>tdh2</i>Δ<i>tdh3</i> yeast survives counter-selection of a GAPDH-encoding plasmid when Sir2 is overexpressed.

<p>(A) The Δ<i>tdh1</i>Δ<i>tdh2</i>Δ<i>tdh3</i> strain MR173 containing the plasmid p(<i>URA3</i>)-<i>Eco</i>GAP was transformed with the indicated <i>HIS3</i> plasmids. Transformants were selected, grown overnight, and spotted in a five-fold serial dilution on SC media containing 5′FOA for counter-selection of the <i>URA3</i> plasmid or on SC media as control. Plates were then incubated for 3 days at 30°C. (B) Similar experiment as described in (A), but using Δ<i>rki1</i> yeast expressing the human <i>RKI1</i> orthologue (Rpi1) from the <i>URA3</i> plasmid. (C) Δ<i>tdh1</i>Δ<i>tdh2</i>Δ<i>tdh3</i> yeast overexpressing Sir2 or its mammalian homologues, human SirT1, human SirT2, and mouse SirT2, were processed as in (A). (D) Similar to (C), but overexpressing the mutant proteins Sir2^H364Y and Sir2^P394L. (E) The yeast strain MR110, in which chromosomal <i>TPI1</i> is deleted and yeast <i>TPI1</i> is expressed from an <i>URA3</i> episome, was transformed with the indicated <i>HIS3</i> plasmids and processed as described above. (F) Similar experiment using the quadruple deletion strain Δ<i>tdh1</i>Δ<i>tdh2</i>Δ<i>tdh3</i>Δ<i>zwf1</i>. (G) Similar to (E), but using yeast strain MR101, which is isogenic to MR110, but expresses human instead of yeast Tpi1 from the <i>URA3</i> episome.</p