Genes encoding Shiga toxin and the intimin receptor detected in faecal samples collected from wild canids

Background: Enteropathogenic Escherichia coli (EPEC) and Shiga toxin-producing E. coli (STEC) are diarrheagenic E. coli that can cause disease in humans. The pathotype EPEC leads to the attaching and effacing lesion, causing damage to the microvilli following to diarrhea. STEC pathotypes produces cytotoxins, which in humans are responsible for hemorrhagic colitis or hemolytic uremic syndrome. Animals are the reservoirs of these pathotypes, especially ruminants. However, other animal’s species can be associated as carriers of EPEC and STEC strains. The aim of this study was to analyze wild canid crab-eating fox (Cerdocyon thous) as potential natural carriers of STEC and EPEC E. coli. Materials, Methods & Results: Seven fecal samples were analyzed from the crab-eating fox of free-living, captured in a peri-urban area. Samples were collected from the rectal ampulla, and the animals were clinic evaluated, being considered healthy at the captured moment. The feces were inoculated on medium MacConkey agar, and then the plates were incubated at 37°C for 24 h. All colony forming units (CFU) were collected by plate washing with ultrapure water (2 mL) and posterior freezing at -20°C. The total bacterial DNA from the CFU collected was extracted, followed by PCR assay to search for three genes: stx1, stx2 (responsible for the synthesis of the Shiga toxin) and tir, which encodes the translocated intimin receptor, related to the A/E lesion formation. Three samples were detected as positive, being one animal detected as carrier of the stx2 gene (STEC strain), while two animals were identified as carrier of the tir gene (EPEC strains).The stx1 gene was not identified on the samples. Also, in the samples, only the presence of one gene studied at a time was observed. Therefore, we have found out that the crab-eating fox can act as reservoirs of STEC and EPEC strains. Discussion: The carrier’s animals of STEC and EPEC strains do not have receptors for the Shiga toxin, serving as asymptomatic vehicle. The wild canids collected and positives to STEC and EPEC E. coli strains analyzed here, did not shown any clinical signs, wherefore they have the potential of being a source of pathogens to other animals and even humans. The observation of this additional wild species, the crab-eating fox, as carriers of STEC and EPEC reinforces the importance of monitoring wild species and the need for caution because of the potential zoonosis. Nevertheless, there are other species of wild animals that were described as rarely-carriers of these pathogens, like deer, wild ruminants and birds. These E. coli pathotypes, potentially foodborne zoonotic pathogens, are acquired by humans from food and water contaminated, by oral-fecal route, or by direct contact with carries animals and their feces. The human contact with wild animals is getting ordinary; because of that, wild animals, like wild canids, may constitute a considerable risk to animal and humans health, mostly by the transmission of these bacteria strains to the environment. In conclusion, the identification of genes encoding Shiga toxin and the intimin receptor in wild canids feces highlight that STEC and EPEC pathogens could be spread by these wild animals. We reinforce that STEC and EPEC pathogens could be naturally carried by wild animals, such as the crab-eating fox, and therefore, is needed further research for better understanding their potential effect, and also the interaction between the pathogen and the host

Smoking fewer than 20 cigarettes per day and remaining abstinent for more than 12 hours reduces carboxyhemoglobin levels in packed red blood cells for transfusion

The prevalence of smokers among blood donors and the effect of smoking on the quality of donated blood have not been extensively explored. In the present study, we determined the prevalence of smoker donors in a large blood bank in Southern Brazil and evaluated the quality of packed red blood cells (RBCs) from these donors through recommended quality control tests and measurement of carboxyhemoglobin (COHb) levels. We then assessed the influence of smoking habits and abstinence before donation on these parameters. Material and methods An observational study was conducted to determine the prevalence of smoking donors, while a prospective cohort study compared conventional hematological and serological parameters and COHb levels at 0, 15, and 30 days after donation in RBCs donated by smokers (N = 31) and nonsmokers (N = 31) and their association with smoking habits and abstinence before donation. Results Of 14,428 blood donations received in 1 year, 5.9% were provided by smokers. Storage over time slightly altered some quality parameters, such as hematocrit, hemoglobin, hemolysis, and COHb levels, in RBC packs. COHb levels were higher in RBC packs from smokers (8%) than from non-smokers (2%), and increased as a function of the number of cigarettes smoked daily and time elapsed since the last cigarette smoked before donation. Lower levels were found in RBC packs from donors who smoked fewer than 20 cigarettes per day or remained abstinent for more than 12h before giving blood. Conclusion Although cigarette smoke had no significant effect on blood quality parameters such as hematocrit, hemoglobin, or hemolysis, it quadrupled COHb levels in packed RBCs. Abstinence from smoking for more than 12h or smoking fewer than 20 cigarettes daily helped decrease COHb levels. Implications Given the increasing prevalence of tobacco use worldwide, we suggest blood banks recommend 12h of tobacco abstinence before donation and analyze COHb levels in donated blood as an approach to reduce risk for high-risk recipients

Supplement 1) Peer-reviewed paper

Abstract This study was conducted to investigate the effect of dietary fatty acids (FA) on the fertility and hatchability of laying hens at the end-of-lay period (69 -77 weeks of age). Five isoenergetic (12.4 MJ ME/kg DM) and isonitrogenous (170 g CP/kg DM) diets were formulated using different lipid sources (30 g/kg inclusion) to manipulate the dietary FA profile. The control diet was formulated using a 50 : 50 blend of linseed and fish oil, while fish oil was used in the polyunsaturated n-3 treatment. Sunflower oil was used in the polyunsaturated n-6 treatment, while in the mono-unsaturated n-9 diet high oleic acid (HO) sunflower oil was used. Lastly, tallow was used as a lipid source in the saturated FA diet. One hundred and twenty five hens (n = 25/treatment) and 50 cockerels (n = 10/treatment) of the Hy-Line Silver-Brown genotype were randomly allocated to the five dietary treatments at 20 weeks of age. From 69 weeks of age, hens were inseminated with 0.06 mL undiluted semen from cockerels within the same dietary treatment. Between 71 and 78 weeks of age (49 days) a total of 588 eggs-per-treatment were collected, individually marked (date and hen number) and incubated in a single-stage still-air incubator. Eggs were candled on D7 and D14 to determine embryonic mortalities and a 24 h window for hatching was allowed (D21 + 24 h). Although the fish oil treatment resulted in the lowest egg weights (59.3 g) and fertility (84.6%), it recorded the highest hatchability (76%). In contrast, the sunflower oil treatment recorded the lowest hatchability (58.2%) of all treatments, despite its high egg fertility (89.6%). Results of the study suggest that the dietary fatty acid content, in particular the n-3 and n-6 levels, need critical consideration in terms of concentration and ratio in the formulation of breeder diets to limit embryonic mortalities during incubation

Influence of dietary lipid sources on sensory characteristics of broiler meat

________________________________________________________________________________ Abstract A study was conducted to determine the influence of different dietary lipid sources and inclusion levels on sensory characteristics of chicken breast meat. Eight isoenergetic (15.1 MJ AME/kg DM) and isonitrogenous (223 g CP/kg DM) diets were formulated, using high oleic sunflower oil (HOSO), sunflower oil (SO), fish oil (FO) and tallow (T) at 30 g/kg and 60 g/kg inclusion levels. Eight hundred, day-old Ross 788 broiler males were randomly allocated to the eight treatments (n = 100) and further subdivided into four replicates/treatment (n = 25). All birds receive a commercial starter diet for the first 14 days, where-after the experimental diets were fed for 28 days. At 42 days of age, three birds/replicate (n = 12/treatment) were randomly selected, weighed and slaughtered at a commercial abattoir. Breast muscles were removed from the chilled carcasses (4 °C) and de-skinned. Meat samples were wrapped in aluminium foil and steamed (200 °C) before cutting into smaller pieces (2.5 cm 3 ) and served to the respondents (n = 75) of a consumer panel. Each respondent tasted eight meat samples while completing a nine-point hedonic scale questionnaire. Meat samples of the HOSO treatment were preferred, while FO samples were the least acceptable to the respondents. These results suggested that dietary lipid sources could be used to manipulate sensory characteristics of broiler breast meat according to consumer preferences. _______________________________________________________________________________

Electronic bandstructure of superconducting KTaO3 (111) interfaces

Two-dimensional electron gases(2DEGs)based on KTaO3 are emerging as a promising platform for spin-orbitronics due to their high Rashba spin-orbit coupling (SOC) and gate-voltage tunability. The recent discovery of a superconducting state in KTaO3 2DEGs now expands their potential towards topological superconductivity. Although the band structure of KTaO3 surfaces of various crystallographic orientations has already been mapped using angle-resolved photoemission spectroscopy(ARPES), this is not the case for superconducting KTaO3 2DEGs. Here, we reveal the electronic structure of superconducting 2DEGs based on KTaO3 (111) single crystals through ARPES measurements. We fit the data with a tight-binding model and compute the associated spin textures to bring insight into the SOC-driven physics of this fascinating system.Comment: 9 pages, 4 figure

Homoplastic microinversions and the avian tree of life

Background: Microinversions are cytologically undetectable inversions of DNA sequences that accumulate slowly in genomes. Like many other rare genomic changes (RGCs), microinversions are thought to be virtually homoplasyfree evolutionary characters, suggesting that they may be very useful for difficult phylogenetic problems such as the avian tree of life. However, few detailed surveys of these genomic rearrangements have been conducted, making it difficult to assess this hypothesis or understand the impact of microinversions upon genome evolution. Results: We surveyed non-coding sequence data from a recent avian phylogenetic study and found substantially more microinversions than expected based upon prior information about vertebrate inversion rates, although this is likely due to underestimation of these rates in previous studies. Most microinversions were lineage-specific or united well-accepted groups. However, some homoplastic microinversions were evident among the informative characters. Hemiplasy, which reflects differences between gene trees and the species tree, did not explain the observed homoplasy. Two specific loci were microinversion hotspots, with high numbers of inversions that included both the homoplastic as well as some overlapping microinversions. Neither stem-loop structures nor detectable sequence motifs were associated with microinversions in the hotspots. Conclusions: Microinversions can provide valuable phylogenetic information, although power analysis indicate

Diving into the vertical dimension of elasmobranch movement ecology

Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements