First record of Giardia assemblage D infection in farmed raccoon dogs (Nyctereutes procyonoides)

The presence of Giardia genotypes was investigated in 18 raccoon dogs ( Nyctereutes procyonoides ) and 80 red foxes ( Vulpes vulpes ) on one farm. To demonstrate Giardia cysts, fresh and trichrome stained smears were microscopically screened. Two molecular markers were used for Giardia genotyping: a fragment of the beta-giardin gene and a fragment of the glutamate dehydrogenase gene. All faecal samples obtained from red foxes were negative. Giardia cysts were identified only in 2 of the 18 raccoon dogs. The result of genotyping and phylogenetic analysis showed that the G. duodenalis from both raccoon dogs belonged to the D assemblage. This finding of a new animal reservoir of G. duodenalis canids-specific genotypes is important in order to eliminate the risk of infecting other animals bred for fur. Further molecular analyses of Giardia isolates in raccoon dogs are required. The present study represents the first contribution to knowledge of G. duodenalis genotypes in raccoon dogs

Biochemical properties of Paracoccus denitrificans FnrP:Reactions with molecular oxygen and nitric oxide

In Paracoccus denitrificans, three CRP/FNR family regulatory proteins, NarR, NnrR and FnrP, control the switch between aerobic and anaerobic (denitrification) respiration. FnrP is a [4Fe-4S] cluster containing homologue of the archetypal O2 sensor FNR from E. coli and accordingly regulates genes encoding aerobic and anaerobic respiratory enzymes in response to O2, and also NO, availability. Here we show that FnrP undergoes O2-driven [4Fe-4S] to [2Fe-2S] cluster conversion that involves up to 2 O2 per cluster, with significant oxidation of released cluster sulfide to sulfane observed at higher O2 concentrations. The rate of the cluster reaction was found to be ~6-fold lower than that of E. coli FNR, suggesting that FnrP can remain transcriptionally active under microaerobic conditions. This is consistent with a role for FnrP in activating expression of the high O2 affinity cytochrome c oxidase under microaerobic conditions. Cluster conversion resulted in dissociation of the transcriptionally active FnrP dimer into monomers. Therefore, along with E. coli FNR, FnrP belongs to the subset of FNR proteins in which cluster type is correlated with association state. Interestingly, two key charged residues, Arg140 and Asp154, that have been shown to play key roles in the monomer-dimer equilibrium in E. coli FNR are not conserved in FnrP, indicating that different protomer interactions are important for this equilibrium. Finally, the FnrP [4Fe-4S] cluster is shown to undergo reaction with multiple NO molecules, resulting in iron nitrosyl species and dissociation into monomers

P. falciparum and P. vivax Epitope-Focused VLPs Elicit Sterile Immunity to Blood Stage Infections

In order to design P. falciparum preerythrocytic vaccine candidates, a library of circumsporozoite (CS) T and B cell epitopes displayed on the woodchuck hepatitis virus core antigen (WHcAg) VLP platform was produced. To test the protective efficacy of the WHcAg-CS VLPs, hybrid CS P. berghei/P. falciparum (Pb/Pf) sporozoites were used to challenge immunized mice. VLPs carrying 1 or 2 different CS repeat B cell epitopes and 3 VLPs carrying different CS non-repeat B cell epitopes elicited high levels of anti-insert antibodies (Abs). Whereas, VLPs carrying CS repeat B cell epitopes conferred 98% protection of the liver against a 10,000 Pb/Pf sporozoite challenge, VLPs carrying the CS non-repeat B cell eptiopes were minimally-to-non-protective. One-to-three CS-specific CD4/CD8 T cell sites were also fused to VLPs, which primed CS-specific as well as WHcAg-specific T cells. However, a VLP carrying only the 3 T cell domains failed to protect against a sporozoite challenge, indicating a requirement for anti-CS repeat Abs. A VLP carrying 2 CS repeat B cell epitopes and 3 CS T cell sites in alum adjuvant elicited high titer anti-CS Abs (endpoint dilution titer \u3e1x106) and provided 80–100% protection against blood stage malaria. Using a similar strategy, VLPs were constructed carrying P. vivax CS repeat B cell epitopes (WHc-Pv-78), which elicited high levels of anti-CS Abs and conferred 99% protection of the liver against a 10,000 Pb/Pv sporozoite challenge and elicited sterile immunity to blood stage infection. These results indicate that immunization with epitope-focused VLPs carrying selected B and T cell epitopes from the P.falciparum and P. vivax CS proteins can elicit sterile immunity against blood stage malaria. Hybrid WHcAg-CS VLPs could provide the basis for a bivalent P. falciparum/P. vivax malaria vaccine

Dietary lipids fuel GPX4-restricted enteritis resembling Crohn’s disease

Abstract: The increased incidence of inflammatory bowel disease (IBD) has become a global phenomenon that could be related to adoption of a Western life-style. Westernization of dietary habits is partly characterized by enrichment with the ω-6 polyunsaturated fatty acid (PUFA) arachidonic acid (AA), which entails risk for developing IBD. Glutathione peroxidase 4 (GPX4) protects against lipid peroxidation (LPO) and cell death termed ferroptosis. We report that small intestinal epithelial cells (IECs) in Crohn’s disease (CD) exhibit impaired GPX4 activity and signs of LPO. PUFAs and specifically AA trigger a cytokine response of IECs which is restricted by GPX4. While GPX4 does not control AA metabolism, cytokine production is governed by similar mechanisms as ferroptosis. A PUFA-enriched Western diet triggers focal granuloma-like neutrophilic enteritis in mice that lack one allele of Gpx4 in IECs. Our study identifies dietary PUFAs as a trigger of GPX4-restricted mucosal inflammation phenocopying aspects of human CD

STRUCTURAL AND OXIDATION-REDUCTION PROPERTIES OF (4-IRON - 4-SULFUR)³⁺ʼ²⁺ FERREDOXINS.

Many biologically important electron transfer reactions involve iron-sulfur centers and flavosemiquinones. Laser flash photolysis and stopped-flow spectrophotometry has been utilized to investigate factors influencing transient kinetic oxidation of free and protein-bound flavosemiquinones by various types of oxidants, but primarily high potential iron-sulfur proteins (HiPIP) and rubredoxin classes of Fe-S proteins. Studies of free flavosemiquinone analog oxidation by Fe-containing redox proteins and inorganic oxidants have found the reactivity of the anionic flavosemiquinone to be greater than that for neutral flavosemiquinone. The second order rate constants of oxidation of various flavosemiquinone analogs by either redox proteins or non-biological oxidants correlate with the difference in redox potential of the reactants according to the Marcus exponential equation. For the protein-flavin analog reactions, deviations from the theoretical Marcus curve are interpreted in terms of the effects of the different exocyclic substitutions on intrinsic anion semiquinone reactivity. Electrostatic effects on FMN and C. pasteurianum flavodoxin semiquinone oxidation by HiPIP can be quantitated yielding the rate constant at infinite ionic strength (k∞) and the charge product for reaction. The magnitude of the electrostatic effects are larger for flavodoxin semiquinone oxidation than for FMN semiquinone oxidation which is consistent with the larger electrostatic charge for flavodoxin. The k∞ values obtained from the electrostatic analysis for FMN semiquinone and flavodoxin semiquinone oxidation indicate a dependence on the redox potential difference between the reactants (ΔE). The ΔE effect is larger in magnitude for the flavodoxin reaction than for the FMN reaction. Deviations from the theoretical curves for the FMN and flavodoxin reactions suggest that factors other than redox potential and electrostatics, such as sterics, could be having an important influence on reactivity. The results suggest that electrostatics, redox potential, and perhaps sterics could have an important role in determining the biological specificity of protein/protein redox reactions. C. pasteurianum rubredoxin forms a 1:1 complex with spinach ferredoxin:NADP+- reductase (FNR) at low ionic strengths. The reduction of Rdₒₓ by lumiflavin semiquinone is unaltered in the complex. Evidence is presented for a rapid (2 x 10³s⁻¹) intracomplex electron transfer from FNR semiquinone to oxidized rubredoxin

Preliminary studies on the inheritance of white coat colour in Arctic foxes [Alopex lagopus L.]

Main genes determining white coat colour in Arctic foxes are: recessive gene d and incompletely dominant, autosomal gene S with lethal effect in homozygous condition. The white coat colour of Arctic foxes bred on Polish farms had been determined solely by the recessive gene until the 1970s, when the Shadow variety was imported from Norway. The genetic code of the two varieties was different, but this fact was not taken into account. The results obtained in the present study do not confirm the theories on the heredity of white coat colour of Arctic foxes. The authors of these theories assumed that the coat colour depends on the presence of a recessive gene, the only factor responsible for the white furcoat. Apart from Polar and Shadow white foxes, there is a wide variety of darker white animals, and this fact suggests that there is a number of cumulative genes responsible for the intensity of coat pigmentation

Fonctionnement de la chambre de desintoxication des alcooliques a Poznan et la caracteristique des personnes arretees

L'appel, l'organisation, l'activité et les tâches de la chambre de désintoxication des alcooliques sont réglés en détail par les dispositions juridiques. Les tâches principales consistent à isoler des personnes ivres jusqu'à leur désintoxication ainsi qu'à leur assurer les services hygiéniques et sanitaires. A l'heure actuelle les chambres de désintoxication des alcooliques sont considérées comme les institutions repressives et d'isolement, non pas celles du caractère thérapeutique. Il nous semble qu'il faudrait traiter les personnes arrêtées de la même manière que l'on traite les malades dans les établissements hospitcliers. Les contacts avec les patients devraient rappeler la façon d'agir adoptée par le personnel des hôpitaux psychiatriques. Le fait de détenir les mineurs dans les chambres de désintoxication des alcooliques paraît bien inquiétant (mineur—personne n'ayant pas 18 ans au moment de l'arrêter). Pour des raisons pédagogiques ils devraient être dirigés plutôt dans les établissements de surveillance et d'éducation — prévus pour les enfants. La chambre de désintoxication des alcooliques de Poznań, organisée en 1957, a eu dans les années 1963 - 1977 plus de 105 mille de patients. Il est nécessaire de souligner que le nombre de patients augmente chaque année (plus de 11 mille en 1977). D'après l'analyse de la structure sociale et professionelle des arrêtés, plus de 60% sont les ouvriers dorait 7% exercent les métiers liés à la sécurité commune. La cinquième des personnes conduites à la chambre à Poznań n'ont pas d'emploi. Dans le période en question plus de 56% de tous les arrêtés ont demeuré à la chambre de désintoxication des alcooliques plus d'une fois. On a exécuté les examens de 200 adultes conduits à la chambre en 1977 ainsi que de tous les mineurs (486) arrêtés dans les années 1970 - 1975. Ces examens concernant leur punissabilité ont été accomplis dans le Registre Central des Condamnés. Dans les groupes en question 32% et 25,3% avaient été déjà condamnés. Le niveau élevé de ce pourcentage témoigne de l'existence des liaisons (au moins des liaisons formelles) entre l'abus des alcools et la criminalité.Digitalizacja i deponowanie archiwalnych zeszytów RPEiS sfinansowane przez MNiSW w ramach realizacji umowy nr 541/P-DUN/201