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Three-dimensionally-printed aortic templates are increasingly being used to aid in the modification of stent grafts in the treatment of urgent, complex aortic disorders, often of an emergency nature. The direct contact between the aortic template and the stent graft implies the necessity of complete sterility. Currently, the efficacy of sterilizing aortic templates and the effect of sterilization on the geometry of tubular aortic models are unknown. A complex case of aortic arch dissection was selected to prepare a 3D-printed aortic arch template, which was then manufactured in six popular printing materials: polylactic acid (PLA), nylon, polypropylene (PP), polyethylene terephthalate glycol (PETG), and a rigid and flexible photopolymer resin using fused deposition modeling (FDM) and stereolithography (SLA). The 3D models were contaminated with Geobacillus stearothermophilus broth and Bacillus atrophaeus. The sterilization was performed using three different methods: heat (105 °C and 121 °C), hydrogen peroxide plasma, and ethylene oxide gas. Before and after sterilization, the aortic templates were scanned using computed tomography to detect any changes in their morphology by comparing the dimensions. All sterilization methods were effective in the elimination of microorganisms. Steam sterilization in an autoclave at 121 °C caused significant deformation of the aortic templates made of PLA, PETG, and PP. The other materials had stable geometries, and changes during mesh comparisons were found to be submillimeter. Similarly, plasma, gas, and heat at 105 °C did not change the shapes of aortic templates observed macroscopically and using mesh analysis. All mean geometry differences were smaller than 0.5 mm. All sterilization protocols tested in our study were equally effective in destroying microorganisms; however, differences occurred in the ability to induce 3D object deformation. Sterilization at high temperatures deformed aortic templates composed of PLA, PETG, and PP. This method was suitable for nylon, flexible, and rigid resin-based models. Importantly, plasma and gas sterilization were appropriate for all tested printing materials, including PLA, PETG, PP, nylon, flexible and rigid resins. Moreover, sterilization of all the printed models using our novel protocol for steam autoclaving at 105 °C was also 100% effective, which could represent a significant advantage for health centers, which can therefore use one of the most popular and cheap methods of medical equipment disinfection for the sterilization of 3D models as well.

The growing interest in bacteriophages and antibiotics' combined use poses new challenges regarding this phenomenon's accurate description. This study aimed to apply the PhageScore methodology to assess the phage-antibiotic combination activity in liquid bacterial culture. For this purpose, previously described Acinetobacter infecting phages vB_AbaP_AGC01, Aba-1, and Aba-4 and antibiotics (gentamicin, ciprofloxacin, meropenem, norfloxacin, and fosfomycin) were used to obtain a lysis curve of bacteriophages under antibiotic pressure. The experimental data were analyzed using the Fractional Inhibitory Concentration Index (FICI) and PhageScore methodology. The results obtained by this method clearly show differences between phage lytic activity after antibiotic addition. Thus, we present the potential use of the PhageScore method as a tool for characterizing the phage antibiotic synergy in liquid culture. Further, the optimization of the PhageScore for this purpose can help compare antibiotics and their outcome on bacteriophage lytic activity.

An intraluminal thrombus (ILT), which accumulates large numbers of neutrophils, plays a key role in abdominal aortic aneurysm (AAA) pathogenesis. This study aimed to compare levels of selected neutrophil inflammatory mediators in thick and thin ILT, plus adjacent AAA walls, to determine whether levels depend on ILT thickness. Neutrophil mediator levels were analysed by enzyme-linked immunosorbent assays in thick and thin segments of ILT, plus adjacent aneurysm wall sections, taken from one aneurysm sac each from 36 AAA patients. In aneurysmal walls covered by thick ILT, neutrophil elastase and TNF-a levels were significantly higher, as were concentrations of IL-6, in thick ILT compared to thin layers. Positive correlations of NGAL, MPO, and neutrophil elastase were observed between thick ILT and the adjacent wall and thin ILT and the adjacent wall, suggesting that these mediators probably infiltrate thick AAA compartments as well as thin. These observations might support the idea that neutrophil mediators and inflammatory cytokines differentially accumulate in AAA tissues according to ILT thickness. The increased levels of neutrophil mediators within thicker AAA segments might suggest the existence of an intensified proinflammatory state that in turn presumably might preferentially weaken the AAA wall at that region.

Background Demodex mites are obligate ectoparasites found in the pilosebaceous follicle and sebaceous gland of many mammals. The aim of the study was to examine prevalence of bacterial infection in Demodex folliculorum infected patients with blepharitis. Methods The study included patients with a diagnosis of blepharitis with D. folliculorum (n=128) and healthy volunteers (n=103). Patients were questioned about their age, sex, social habits, and literacy status and per capita income. The examination consisted of examining the vision of the patient with and without ocular correction, tonus in both eyes and a careful examination of the anterior segment of both eyes. The bacterial culture of the conjunctival sac was obtained by inoculating the samples on Columbia agar with 5% sheep blood and identified based on morphological characteristics and stained by the Gram method. Species identification was performed by coagulase test or VITEK Compact. ResultsPhysiological flora was found in 8.7% participants from uninfected and all infected with D. folliculorum patients. We isolated Staphylococcus aureus, Acinetobacter baumannii, Streptococcus pneumoniae, Klebsiella oxytoca, and Bacillus spp. in the conjunctival sac only in patients infected with D. folliculorum. In patients with D. folliculorum infection mean intraocular pressure and visual acuity were lower than in uninfected participants. ConclusionsPatients infected with D. folliculorum should also undergo microbiological examination of conjunctival swabs. The treatment of each patient should be individualized, adapted to the clinical condition, and in cases of bacterial co-infection.

Background: Pseudomonas aeruginosa is a Gram-negative bacteria responsible for infections in immunocompromised patients and is one of the most common causes of nosocomial infections particularly in intensive care and burn units. We aimed to investigate the population structure of P. aeruginosa strains isolated from patients at different hospital wards. Methods: We analysed the possible presence of P. aeruginosa epidemic or endemic strains in hospitals of the selected region. A genotyping analysis was performed for 202 P. aeruginosa isolates collected from patients of eleven hospitals in north-western Poland. Collections of P. aeruginosa were genotyped using pulsed-field gel electrophoresis (PFGE). Phenotypic screening for antibiotic susceptibility was performed for the common antimicrobial agents.Results: P. aeruginosa isolates were distributed among 116 different pulsotype groups. We identified 30 groups of clonally related strains, each containing from 2 to 17 isolates and typed the obtained 13 unique patterns, designated as A, D, E, J, K, M, N, Ó, P, T, X, AC, AD, and AH. The two largest clusters, D and E, contained 17 and 13 isolates, respectively. Strains of these groups were continuously isolated from patients at intensive care units and burn units, indicating transmission of these strains. Conclusions: In this study, we demonstrate the clonal relatedness of P. aeruginosa strains and their constant exchange in hospitals over a period of 15 months. The obtained results indicate a predominantly non-clonal structure of P. aeruginosa.

Background Pseudomonas aeruginosa is a Gram-negative bacteria responsible for infections in immunocompromised patients and is one of the most common causes of nosocomial infections particularly in intensive care and burn units. We aimed to investigate the population structure of P. aeruginosa strains isolated from patients at different hospital wards. Methods: We analysed the possible presence of P. aeruginosa epidemic or endemic strains in hospitals of the selected region. A genotyping analysis was performed for P. aeruginosa isolates (n = 202) collected from patients of eleven hospitals in north-western Poland. Collections of P. aeruginosa were genotyped using pulsed-field gel electrophoresis (PFGE). Phenotypic screening for antibiotic susceptibility was performed for the common antimicrobial agents. Results Pseudomonas aeruginosa isolates were distributed among 116 different pulsotype groups. We identified 30 groups of clonally related strains, each containing from 2 to 17 isolates and typed the obtained 13 unique patterns, designated as A, D, E, J, K, M, N, Ó, P, T, X, AC, AD, and AH. The two largest clusters, D and E, contained 17 and 13 isolates, respectively. Strains of these groups were continuously isolated from patients at intensive care units and burn units, indicating transmission of these strains. Conclusions In this study, we demonstrate the clonal relatedness of P. aeruginosa strains and their constant exchange in hospitals over a period of 15 months. The obtained results indicate a predominantly non-clonal structure of P. aeruginosa.

Background: The ectoparasite Demodex spp. is the most common human parasite detected in skin lesions such as rosacea, lichen, and keratosis. It is also an etiological factor in blepharitis. As Demodex spp. is involved in the transmission of pathogens that can play a key role in the pathogenesis of demodecosis, the aim was to assess the concurrence of Demodex folliculorum and bacterial infections.Methods: The study involved 232 patients, including 128 patients infected with Demodex folliculorum and 104 non-infected patients. The ophthalmological examination consisted of examining the vision of the patient with and without ocular correction, tonus in both eyes) and a careful examination of the anterior segment of both eyes with special emphasis on the appearance of the eyelid edges and the structure and appearance of eyelashes from both eyelids of both eyes. The samples for microbiological examination were obtained from the conjunctival sac. The bacterial culture was obtained by inoculating the samples on chocolate agar and agar with 5% sheep blood. After 24-48 h of incubation at 37 °C, the growth of various colonies of bacteria was identified based on morphological evaluation of the colonies on the media and preparations stained by the Gram method. Species identification was performed biochemical examination ex. coagulase test or VITEK Compact (bioMerieux, Poland).Results: Physiological flora was found in all patients infected with D. folliculorum and 9 (8.7%) participants from the control group.Only in patients infected with D. folliculorum we isolated Staphylococcus aureus (9 patients, 7%), Acinetobacter baumannii (one patient, 0.8%), Streptococcus pneumoniae (one patient, 0.8%), Klebsiella oxytoca (one patient, 0.8%), and Bacillus spp. (one patient, 0.8%) in the conjunctival sac.Conclusions: The occurrence of symptoms: dryness and burning sensation in the eye, tearing, conjuctival redness, foreign body sensation, eyelash loss, blockage of the Meibomian glands, cylindrical dandruff, and chalazia may suggest infection with Demodex spp. Patients infected with Demodex spp. should also undergo microbiological examination of conjunctival swabs. The treatment of each patient should be individualized, adapted to the clinical condition, and in cases of bacterial co-infection. Furthermore, daily hygiene of the eyelid margins should be recommended.

The aim of this study was to investigate the impact of environmental factors on the concentrations of vanadium (V), chromium (Cr), and calcium (Ca) and to examine the synergistic or antagonistic relationships between these metals, in cartilage (C), cortical bone (CB), and spongy bone (SB) samples obtained following hip joint surgery on patients with osteoarthritis in NW Poland. We found significantly higher concentrations of V and Cr in spongy bone in patients who consumed game meat and also those with prosthetic implants. Chromium levels were significantly lower in patients with kidney diseases. The greatest positive correlations were found between spongy bone V and (i) the amount of consumed beer and (ii) seafood diet. Correlation analysis also showed a significant correlation between Cr levels and seafood diet. To a certain extent these results indicate that the concentrations of V, Cr, and Ca in the human hip joint tissues are connected with occupational exposure, kidney diseases, diet containing game meat, sea food, beer, and the presence of implants. Furthermore, we noted new types of interactions in specific parts of the femoral head. Vanadium may contribute to the lower bone Ca levels, especially in the external parts (cartilage and cortical bone).

OBJECTIVE The aim of the study was to determine the degree of colonization Streptococcus agalactiae (GBS--Group B Streptococcus) in women at 35.-37. weeks of pregnancy and to evaluate drug susceptibility of the isolated strains. MATERIAL AND METHODS We analyzed the results of 1111 tests for GBS colonization performed between 2010-2013 in pregnant women (aged 16-40) from the West Pomeranian region. Swabs were taken from the vagina and the anus of the study subjects at 35.-37. weeks of pregnancy Materials were cultured on Granada Agar and in selective Todd-Hewitt broth, which was next cultured on Granada Agar The degree of GBS colonization was determined by the semi-quantitative method on solid media. The strains were tested for susceptibility to penicillin, erythromycin and clindamycin by disc diffusion method according to the EUCAST standards. RESULTS Positive cultures for S. agalactiae were found in 22.5% of the pregnant women. The highest (25.4%) and the lowest (15.9%) rates of GBS colonization were observed in the age groups of 31-35 and 16-20 years, respectively Massive GBS colonization was detected in 68.4% of pregnant subjects, with the highest and the lowest rates in the age groups of 31-35 and 16-20 years, (75.3% and 50.0%, respectively). All isolated GBS strains were sensitive to penicillin. Macrolide, lincosamide and streptogramin B resistance (MLSB) was found in 28% of the isolates, resistance only to erythromycin (phenotype M) in 2% of the strains. There were no significant differences in the degree of GBS colonization and drug sensitivity of GBS strains versus the year of our examination. CONCLUSIONS Monitoring for GBS colonization in the last weeks of pregnancy seems to be necessary for effective prevention of S. agalactiae infections.