Search Results (7)

Background/Objectives: Endodontically treated molars are structurally weakened due to internal tissue loss, increasing their risk of fracture. Endocrowns, developed as a conservative alternative to post–core systems, have gained popularity with the rise of digital dentistry, CAD/CAM workflows, and 3D-printed restorations. In this context, the aim of the present pilot study was to investigate the influence of cement layer thickness, intracoronal depth, and dentine wall thickness on the fracture resistance of molars restored with 3D-printed endocrowns. Methods: Twelve extracted human molars were endodontically treated and restored with endocrowns fabricated from a 3D-printed resin material, SprintRay Crown^TM (SprintRay Inc. Los Angeles, CA, USA), via masked stereolithography (MSLA) on a Prusa SL1 printer. Cementation was performed using RelyX Universal Resin Cement (3M, Maplewood, MN USA). Cone beam computed tomography (CBCT) was used to measure the dentine thickness and intracoronal depth before cementation and cement thickness after cementation. The fracture resistance was evaluated using a universal testing machine. For each variable (Td, Dp, Tc), the 12 specimens were divided into two groups (n = 6). Statistical analysis included Pearson correlation, a one-way ANOVA, and the non-parametric Mann–Whitney U test. Results: Within the limitations of this pilot in vitro study, cement thickness demonstrated a strong positive correlation with fracture resistance (r = 0.577) and was the only variable showing statistical significance in the ANOVA (F = 7.847, p = 0.019). In contrast, intracoronal depth and dentine wall thickness exhibited weaker and nonsignificant correlations. No significant mechanical advantage was observed from increasing the pulp chamber depth or peripheral dentine wall thickness. This result was further supported by nonparametric Mann–Whitney U testing (p = 0.015). Conclusions: Cement layer thickness is a key biomechanical factor influencing the fracture resistance of endocrown restorations. Preparation depth and dentine wall geometry appear to have a less direct impact. Full article

Salmonella Dublin (S. Dublin) and Salmonella Typhimurium (S. Typhimurium) are commonly linked to bovine salmonellosis. S. Dublin is, however, considered a bovine-adapted serovar for primarily infecting and thriving in cattle. Using S. Typhimurium (a generalist serovar) as a benchmark, this study investigates genomic factors contributing to S. Dublin’s adaptation to cattle hosts in the U.S. A total of 1337 S. Dublin and 787 S. Typhimurium whole-genome sequences from bovine sources were analyzed with CARD (version 4.0.0), ARG-NOTT (version 6), and AMRfinderPlus (version 4.0.3) for antimicrobial resistance (AMR) genes; VFDB and AMRfinderPlus for virulence genes; AMRFinderPlus for stress genes; and Plasmidfinder for plasmids. Existing clonal groups among isolates of the two serovars were also investigated using the Hierarchical Clustering of Core Genome Multi-Locus Sequence Typing (HierCC-cgMLST) model. The results revealed minimal genomic variation among S. Dublin isolates. Comparatively, the IncX1 plasmid was somewhat exclusively identified in S. Dublin isolates and each carried an average of four plasmids (p-value < 0.05). Furthermore, S. Dublin isolates exhibited a higher prevalence of AMR genes against key antimicrobials, including aminoglycosides, beta-lactams, tetracyclines, and sulfonamides, commonly used in U.S. cattle production. Additionally, Type VI secretion system genes tssJKLM and hcp2/tssD2, essential for colonization, were found exclusively in S. Dublin isolates with over 50% of these isolates possessing genes that confer resistance to heavy metal stressors, like mercury. These findings suggest that S. Dublin’s adaptation to bovine hosts in the U.S. is supported by a conserved genetic makeup enriched with AMR genes, virulence factors, and stress-related genes, enabling it to colonize and persist in the bovine gut. Full article

Background and objectives: Regular moderate exercise is considered a protector against chronic inflammatory diseases. Intense exercise causes a significant release of pro-inflammatory cytokines and free radicals depending on exercise intensity and duration. The aim of this study was to investigate the effects of antioxidant supplementation on parameters of immunity and inflammation in athletes. Methods: The study included 14 elite rowers (group 1) and 10 recreational athletes (group 2). All participants were supplemented with 500 mg/day (500 IU SOD) plant-origin superoxide dismutase (GliSODin®) during a 6-week pre-competition microcycle preparation period (rowers, 120 min training/6 days weekly; recreational athletes, 60 minutes training/3 days weekly). Venous blood samples were taken in the morning after a 24-hour resting period. White blood cell (WBC) and its subpopulation count were determined using an AcT Diff Hematology Analyzer (Beckman Coulter, Inc., Brea, CA, USA) and CRP concentration using the biochemistry analyzer Olympus AU400 (Beckman Coulter, Inc., Brea, CA, USA) at the Faculty of Pharmacy, University of Belgrade. Selected cytokines IL-4, IL-6, IL-8, and IL-10 were measured by hs ELISA kits (R&D Systems). All data were analyzed using nonparametric tests (Mann–Whitney U test, Kruskal–Wallis test). Results: WBCs and their subpopulation were all in the reference range in both groups before and after supplementation, without significant differences within and between groups according to tests considering supplementation. In rowers, IL-6 was significantly higher before and after supplementation (p ˂ 0.001, p ˂ 0.001 respectively), CRP was higher before supplementation (p = 0.025), and IL-10 was higher at initial and final testing (p = 0.030, p = 0.040 respectively). In the recreational group, IL-8 and IL-4 were higher at both measuring points (p ˂ 0.001 and p ˂ 0.01 respectively). Observing changes in variables within the groups, there was a significantly decreased level of IL-6 (p = 0.019) and increased level of IL-4 (p = 0.001) in rowers and a higher IL-4 level in the recreational group (p = 0.059) after supplementation. Discussion: The results of this investigation indicate that there are positive effects of Glisodin supplementation on parameters of inflammation (decreased IL-6, increased IL-4), especially in highly trained rowers, who are more prone to exercise-related oxidative stress. More studies including a greater number of participants are necessary to confirm the influence of antioxidant supplementation on immunity and inflammation in athletes. Full article

The use of chlorhexidine-based mouthwashes on resin composites with rough surfaces can cause discoloration which compromises the esthetic of patients. The present study aimed to evaluate the in vitro color stability of Forma (Ultradent Products, Inc., South Jordan), Tetric N-Ceram (Ivoclar Vivadent, Schaan, Liechtenstein) and Filtek Z350XT (3M, ESPE, St. Paul, MN, USA) resin composites, with and without polishing, after being immersed in a 0.12% chlorhexidine (CHX)-based mouthwash at different times. The present in vitro experimental and longitudinal study used 96 nanohybrid resin composite blocks (Forma, Tetric N-Ceram and Filtek Z350XT) 8 mm in diameter and 2 mm thick, evenly distributed. Each resin composite group was divided into two subgroups (n = 16) with and without polishing and then immersed in a 0.12% CHX-based mouthwash for 7, 14, 21 and 28 days. Color measurements were performed with a calibrated digital spectrophotometer. Nonparametric tests were used to compare independent (Mann–Whitney U and Kruskal–Wallis) and related (Friedman) measures. In addition, the Bonferroni post hoc correction was used considering a significance level of p < 0.05. All polished and unpolished resin composites presented color variation < 3.3 when immersed for up to 14 days in 0.12% CHX-based mouthwash. The polished resin composite with the lowest color variation (ΔE) values over time was Forma, and the one with the highest values was Tetric N-Ceram. When comparing the color variation (ΔE) over time, it was observed that the three resin composites, with and without polishing, presented a significant change (p < 0.001), although these changes in color variation (ΔE) were evident from 14 days between each color acquisition (p < 0.05). The unpolished Forma and Filtek Z350XT resin composites showed significantly more color variation than the same polished ones at all times when immersed in a 0.12% CHX-based mouthwash for 30 s daily. In addition, every 14 days, all three resin composites with and without polishing showed a significant color change, while, every 7 days, color stability was maintained. All the resin composites showed clinically acceptable color stability when exposed for up to 14 days to the above-mentioned mouthwash. Full article

Background: Social support has a vital role in preventing traumatic stress in nurses. Nurses are regularly exposed to contact with violence, suffering, and death. The situation worsened during the pandemic because they were also faced with the possibility of infection SARS-CoV-2 and death from COVID-19. Many nurses are faced with increased pressure, stress, and other adverse effects on their mental health. The study aimed to measure the relationship between compassion fatigue and perceived social support in polish nurses. Methods: The study was conducted on 862 professionally active nurses in Poland using the CAWI method (Computer-Assisted Web Interview). The professional Quality of Life scale (ProQOL) and the Multidimensional Scale of Perceived Social Support (MSPSS) were used for collecting the data. StatSoft, Inc. (2014) was used for data analysis. For comparisons between the groups: Mann–Whitney U test, ANOVA Kruskal–Wallis test, and multiple comparisons (post-hoc). The relationships between variables were tested using Spearman’s rho, Tau Kendall, and the chi-square test. Results: The research showed the presence of compassion satisfaction, compassion fatigue, and burnout in the group of Polish hospital nurses. A higher level of perceived social support was associated with lower compassion fatigue (r = −0.35; p < 0.001). A higher level of social support was associated with higher job satisfaction (r = 0.40; p < 0.001). The study also found that a higher level of social support was associated with a lower risk of burnout (r = −0.41; p < 0.001). Conclusions: Preventing compassion fatigue and burnout should be a priority for healthcare managers. Notably, an essential predictor of compassion fatigue is that Polish nurses often work overtime. It is necessary to pay more attention to the crucial role of social support in preventing compassion fatigue and burnout. Full article

KfrC proteins are encoded by the conjugative broad-host-range plasmids that also encode alpha-helical filament-forming KfrA proteins as exemplified by the RA3 plasmid from the IncU incompatibility group. The RA3 variants impaired in kfrA, kfrC, or both affected the host’s growth and demonstrated the altered stability in a species-specific manner. In a search for partners of the alpha-helical KfrC protein, the host’s membrane proteins and four RA3-encoded proteins were found, including the filamentous KfrA protein, segrosome protein KorB, and the T4SS proteins, the coupling protein VirD4 and ATPase VirB4. The C-terminal, 112-residue dimerization domain of KfrC was involved in the interactions with KorB, the master player of the active partition, and VirD4, a key component of the conjugative transfer process. In Pseudomonas putida, but not in Escherichia coli, the lack of KfrC decreased the stability but improved the transfer ability. We showed that KfrC and KfrA were involved in the plasmid maintenance and conjugative transfer and that KfrC may play a species-dependent role of a switch between vertical and horizontal modes of RA3 spreading. Full article

Background and Objectives: Chronic kidney disease (CKD) is an important public health problem associated with, e.g., progressive renal insufficiency, bone mineral disorders, and increased inflammatory marker levels. The objective of this study was to compare selected biochemical parameters and to evaluate potential correlations between selected anthropometric parameters and levels of sclerostin and interleukin 6 (IL-6) in blood plasma. Materials and Methods: The study group consisted of 34 patients aged 59.8 ± 9.8 years, receiving hemodialysis therapy. The control group consisted of 31 individuals aged 55.4 ± 9.37 years, presenting with GFR (glomerular filtration rate) of more than 60 mL/min/1.73 m². Selected anthropometric and biochemical parameters were assessed at baseline, as well as 3 and 6 months into the study. Statistical analyses were performed using the Statistica 2014 software package (StatSoft, Inc.Tulsa, OK, USA). Analyses included descriptive statistics, intergroup comparisons using the Mann-Whitney U-test or the Kruskal-Wallis test, and Spearman’s correlation analysis. The significance level was set at p ≤ 0.005. Results: At all measurement time points, i.e., at baseline, at month 3, and at month 6, the IL-6 levels in the study group were significantly higher than those in the control group. No correlations were observed in the study group between SCL or IL-6 levels and anthropometric parameters such as body weight, body mass index (BMI), or waist circumference. Conclusions: Patients receiving hemodialysis replacement therapy present with significantly higher levels of IL-6 in their blood. Anthropometric parameters (body weight, BMI, and waist circumference) have no impact on sclerostin and IL-6 levels in patients undergoing hemodialysis therapy. The results obtained are satisfactory, and the research will be continued. Full article