Egg Yolk as a New Source of Peptides with Antioxidant and Antimicrobial Properties.

A significant increase in interest in food-derived peptides obtained mostly through enzymatic reactions has been observed in the past few years. One of the best sources of bioactive peptides are defatted egg yolk proteins, which can potentially find application as high-quality nutritional supplements for infants with cow's milk protein intolerance and as natural preservatives. The aim of this study was to obtain peptides from defatted egg yolk protein, to study their antioxidant and antimicrobial properties, and to identify peptides with bioactive properties To control the course of the process, MALDI-TOF/MS (matrix-assisted laser desorption/ionization time-of flight/mass spectrometry) spectra were also examined. The peptide mixture obtained through enzyme digestion was tested for its antioxidant properties by measuring the scavenging activity in 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cation decolorization (ABTS•+), and ferric reducing activity (FRAP) assays. Antimicrobial activity was also studied. The peptide mixture exhibited significant antioxidant activity: DPPH-1776.66 ± 32.99, ABTS-390.43 ± 8.92, and FRAP-16.45 ± 0.19. The inhibition of bacterial growth by two concentrations of the peptide mixture was examined. The best result was obtained in Bacillus cereus, with an inhibition zone of 20.0 ± 1.0 and 10.7 ± 0.6 mm at the concentrations of 50 and 25 mg/mL, respectively. The results of the study suggest that the mixture of egg yolk peptides may exhibit a number of health-promoting properties.

Utilizing an Amino Acid Scaffold to Construct Heteroditopic Receptors Capable of Interacting with Salts under Interfacial Conditions.

A 4-nitro-L-phenylalanine scaffold was used to construct effective ion pair receptors capable of binding anions in an enhanced manner with the assistance of alkali metal cations. A benzocrown ether was linked to a receptor platform via the amide function so as to support the squaramide function in anion binding and to allow all three NHs to act simultaneously. The binding properties of the receptors were determined using UV-vis, 1H NMR, 2D NMR, and DOSY spectroscopy in MeCN and in the solid state by X-ray measurements. Ion pair receptor 2 was found to interact with the most strongly with salts, and the removal of its key structural elements was shown to hinder the receptor action. The amide proton was recognized to switch from having involvement in an intramolecular hydrogen bond to interacting with anions upon complexation. Apart from carboxylates, which promote deprotonation, and other monovalent salts creating 1:1 complexes with the receptor, more complex equilibria were established upon the complexation of 2 with sulfates. Receptor 2 was shown to be capable of the extraction of ion pairs from the aqueous to organic phase and of the cation-enhanced transport chloride and sulfate anions across a bulk chloroform membrane. These features may open the door for its use in regulating ion concertation under interfacial conditions and acting as a potential drug to treat channelopathies.

Evaluation of the positive predictive value (PPV3) of ACR BI-RADS category 4 and 5 based on the outcomes of Invasive Diagnostic Office in an outpatient clinic.

PURPOSE: The American College of Radiology (ACR) BI-RADS classification is the applicable for breast lesion assessment. BI-RADS categories 4 and 5 need to be followed by biopsy. The aim of our study was to evaluate the tissue biopsy-proven positive predictive value (PPV3) for BI-RADS 4 (and its subcategories) and for BI-RADS 5, and BI-RADS distribution, in comparison to ACR assumptions and literature. MATERIAL AND METHODS: We retrospectively analysed biopsies performed in our outpatient clinic in 2017. Our target group of patients consisted of 797 patients at the average age of 52 years. RESULTS: BI-RADS 5 constituted 12% of cases (95 cases), and BI-RADS 4 88% (698 cases). Within BI-RADS 4 subdivisions there were 359 cases in 4a (45.3%), 215 in 4b (27%), and 124 in 4c (15.6%). Overall PPV3 was 34.8%. BI-RADS 5 category PPV3 number was 97.89%. In category BI-RADS 4 the values of PPV3 equalled 26.22% without subdivision and 3.6%, 27.9%, and 88.7% for subcategories BI-RADS 4a, 4b, and 4c, respectively. CONCLUSIONS: BI-RADS categorisation by radiologists in the studied group matches the literature data according to achieved PPV and BI-RADS percentage distribution. The stratification of cancer risk among categories was proven with Mann-Whitney U test p value < 0.005. There was a statistically important unaccepted difference of PPV3 between core biopsy and vacuum-assisted biopsy, which needs further investigation.

Helicobacter pylori outer membrane vesicles involvement in the infection development and Helicobacter pylori-related diseases.

Helicobacter pylori - (H. pylori) play a role in the pathogenesis of gastritis, gastric and duodenal ulcers as well as gastric cancer. A possible involvement of outer membrane vesicles (OMVs) produced by H. pylori in the distribution of bacterial antigens through the gastric epithelial barrier and their role in the development of local and systemic host inflammatory and immune responses has been suggested. OMVs contain various biologically active compounds, which internalize into host cells affecting signaling pathways and promoting apoptosis of gastric epithelial and immunocompetent cells. OMVs-associated H. pylori virulence factors may strengthen or downregulate the immune responses leading to disease development. This review describes the biological importance of H. pylori OMVs and their role in the course of H. pylori infections, as well as H. pylori related local and systemic effects.

Bacterial Flora Associated with Diseased Freshwater Ornamental Fish.

INTRODUCTION: Ornamental fish can suffer from different bacterial diseases. Among them the most prevalent are infections caused by Aeromonas, Shewanella, Citrobacter, Plesiomonas, Edwardsiella, and Pseudomonas. But there is a broad spectrum of rarely identified bacteria which may be causative agents of diseases. The aim of the study was to determine the species of bacteria pathogenic for fish which are prevalent in aquariums. MATERIAL AND METHODS: Bacteria were isolated from infected ornamental fish from pet shops and private aquariums in the Lublin region in 2015 and classified to species using MALDI-TOF MS. RESULTS: A total of 182 isolates from ornamental fish were identified. The most frequent bacteria found in diseased fish were Aeromonas veronii (30.8% of total number of strains), A. hydrophila (18.7%), Shewanella putrefaciens (7.1%), Citrobacter freundii (7.1%), Pseudomonas spp. (7.1%), Shewanella baltica (4.9%), and Plesiomonas shigelloides (3.3%). CONCLUSION: Isolated bacterial species are facultative pathogens for fish and humans and may be isolated from fish without apparent symptoms of the disease.