Silver nanoparticles represent a threat to biota and have been shown to cause harm through a number of mechanisms, using a wide range of bioassay endpoints. While nanoparticle concentration has been ...primarily considered, comparison of studies that have used differently sized nanoparticles indicate that nanoparticle diameter may be an important factor that impacts negative outcomes. In considering this, the aim of the present study was to determine if different sizes of silver nanoparticles (AgNPs; 10, 20, 40, 60 and 100 nm) give rise to similar effects during embryogenesis of Mediterranean sea urchins Arbacia lixula and Paracentrotus lividus, or if nanoparticle size is a parameter that can modulate embryotoxicity and spermiotoxicity in these species. Fertilised embryos were exposed to a range of AgNP concentrations (1−1000 µg L−1) and after 48 h larvae were scored. Embryos exposed to 1 and 10 µg L−1 AgNPs (for all tested sizes) showed no negative effect in both sea urchins. The smaller AgNPs (size 10 and 20 nm) caused a decrease in the percentage of normally developed A. lixula larvae at concentrations ≥50 µg L−1 (EC50: 49 and 75 μg L−1, respectively) and at ≥100 µg L−1 (EC50: 67 and 91 μg L−1, respectively) for P. lividus. AgNPs of 40 nm diameter was less harmful in both species ((EC50: 322 and 486 μg L−1, for P. lividus and A. lixula, respectively)). The largest AgNPs (60 and 100 nm) showed a dose-dependent response, with little effect at lower concentrations, while more than 50% of larvae were developmentally delayed at the highest tested concentrations of 500 and 1000 µg L−1 (EC50(100 nm); 662 and 529 μg L−1, for P. lividus and A. lixula, respectively. While AgNPs showed no effect on the fertilisation success of treated sperm, an increase in offspring developmental defects and arrested development was observed in A. lixula larvae for 10 nm AgNPs at concentrations ≥50 μg L−1, and for 20 and 40 nm AgNPs at concentrations >100 μg L−1. Overall, toxicity was mostly ascribed to more rapid oxidative dissolution of smaller nanoparticles, although, in cases, Ag+ ion concentrations alone could not explain high toxicity, indicating a nanoparticle-size effect.
ObjectivesLittle is known whether specialists in different dental fields assess orofacial esthetics differently due to various focus of their interest. The aim was to find out if there is a ...difference in judgement of orofacial esthetics among specialists in three different fields of Dental Medicine, i.e. specialists in Prosthodontics (S-Prosthod), Periodontology (S-Perio), and Orthodontics (S-Ortho). Material and methodsA total of 69 specialists (23 participants in each group) assessed the same 60 photographs of the lower third of the face of young healthy people with Angle Class I and natural teeth while smiling. Moreover, the assessed anterior teeth on the photographs of similes had to be without any restorations. The assessments were made using 7 out of 8 Items of Orofacial Esthetic Scale (OES). A face profile assessment was not performed. A Likert 1-5 scale was used for assessments (1-the worst score; 5-the best score). Mean values of summary scores as well as of each OES item were calculated for each specialist for further statistical analysis. One-sample Kolmogorov-Smirnov test, descriptive statistics, one-way ANOVA, and Sheffe post-hoc tests were performed. ResultsThe specialists in Periodontology gave significantly lowest scores to all 7 items related to orofacial esthetics, while the specialists in Prosthodontics gave the highest scores (p<0.05). ConclusionAssessments of orofacial esthetics differ significantly among specialists in Prosthodontics, Periodontology and Orthodontics. Further study is needed to clarify the factors which influence the judgement, and to find out if specific education in certain specialties can modify the assessment.
Rapid development and expanding deployment of additive manufacturing mark this technology as an acceptable alternative to traditional methods of production in terms of speed and quality. All types of ...additive manufacturing technologies build objects layer by layer, therefore anisotropy of mechanical properties is often encountered, making it difficult to accurately predict the mechanical behavior of additively manufactured parts. This paper examines the mechanical properties of additively manufactured parts and the creation of an anisotropic digital material model that can be used to accurately simulate the behavior of additively manufactured parts using FEA (Finite Element Analysis). A three-point bending test was performed on samples created using SLA (Stereolithography) technology. The identical bending scenario was computer modeled using FEA, while the modified manufacturer's data was used for digital material creation. Comparison and analysis of the experimentally obtained results and the results of the FEA were performed.
The objective of this research was to isolate and identify lactic acid bacteria living in the digestive tract of the queen scallop Aequipecten opercularis and further test it as a probiotic culture ...on the growth of the bivalve during one month in captivity. Classic microbiological techniques (API and MALDI TOF) were used and four different strains of Lactiplantibacillus and one Lactococcus were identified and further analyzed, namely: Lactiplantibacillus plantarum I, Lactiplantibacillus plantarum 1, Lactiplantibacillus plantarum 2, Lactococcus lactis, and Lactiplantibacillus brevis. The isolated cultures were further tested for the highest antimicrobial activity towards the most common marine pathogens and survival at different temperatures and pH levels. The strain Lactiplantibacillus plantarum I had the best results, with the highest antimicrobial activity (77–85% pathogen growth inhibition) and the best safety standards showing no antibiotic resistance, and no ability to synthesize biogenic amine and degrade red blood cells. Considering all the abovementioned characteristics, the strain Lpb. plantarum I was further tested on the growth and health status of the bivalve Aequipecten opercularis during a month of cultivation in captivity. The results showed that the incorporation of Lpb. plantarum I led to a decrease in the quantity of test microorganisms in the bivalve and an increase in both the growth rate weight and growth rate length of the queen scallop A. opercularis. Furthermore, the scallops fed with the algae culture + Lpb. plantarum I gained significantly higher meat yield (33.15 ± 2.63%) compared with the control scallops fed only with the algae culture (29.66 ± 2.87%). To conclude, the results from this research indicate that including Lpb. plantarum I as a dietary supplement could enhance growth performance and serve as a feasible approach to reduce pathogen levels while cultivating A. opercularis in captivity.
The use of probiotics in the diet of bivalves poses a great potential in aquaculture as an alternative to antibiotics. The aim of this study was to assess the effect of Lactiplantibacillus plantarum ...I on the phenolic content and antioxidant capacity (AC) of queen scallop extracts after one month of feeding. Total phenols (TP) ranged from 28.17 ± 3.11 to 58.58 ± 8.57 mg GAE/100 g, total non-flavonoids (TNF) from 23.33 ± 3.66 to 36.56 ± 9.91 mg GAE/100 g, and total flavonoids (TF) from 10.56 ± 5.57 to 30.16 ± 1.69 mg CE/100 g. AC was assessed via three different methods: the ferric-reducing ability of plasma assay (FRAP), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic) acid assay (ABTS), and 2,2-diphenyl-1-picryhydrazyl assay (DPPH). FRAP values ranged from 0.13 ± 0.03 to 0.17 ± 0.02 µM AA/g, ABTS from 0.68 ± 0.11 to 2.79 ± 0.34 µM AA/g, and DPPH from 1.75 ± 0.17 to 2.98 ± 0.53 µM AA/g. Among all extracts, the best phenolic content and AC were observed in water extracts from queen scallops. The bivalves treated with the Lactiplantibacillus plantarum I-enriched diet showed higher AC according to the FRAP assay in all extracts. A significant correlation was observed between AC and TP and TNF in control and Lactiplantibacillus plantarum I-treated scallops.
This study examined the effects of dietary supplementation of queen scallop
with an indigenous strain of lactic acid bacteria (LAB),
I, previously isolated from its digestive tract, on gut microbial ...populations and growth rates during cultivation under simulated climate change conditions (pH 7.8, T = 16 ± 2 °C). After one month of feeding, the results showed a noticeable reduction in aquaculture diseases causing pathogens while maintaining sufficient viable
I cells. A higher pH and temperature resulted in higher growth rates, measured by the weight and length of scallops, compared to the control group. The results obtained shed light on the influence of the addition of lactic acid bacteria on the growth of bivalve mollusks under normal and climate change conditions, and provide control of pathogenic microorganisms. In the context of climate change, host-pathogen interactions need to be recognized and put under control by applying natural solutions to minimize the environmental footprint.
The aim of this study was to find the source of
in the intensive care unit (ICU) after an outbreak during the coronavirus disease 2019 (COVID-19) pandemic, as there was no
detected on usually ...screened susceptible surfaces. The screening of the ICU environment was done in April 2021 when eleven different samples were taken. One
isolate was recovered from the air conditioner and was compared with four clinical
isolates obtained from patients hospitalized in January 2021. Isolates were confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), minimum inhibitory concentrations (MICs) were determined, and the multilocus sequence typing (MLST) was performed. The molecular identification of
isolates as ST208, the presence of the same
carbapenemase gene, and the same antibiotic susceptibility profile suggest that the isolate recovered from the air conditioner is the same as the isolates recovered from hospitalized patients. The environmental isolate was recovered three months later than the clinical isolates, emphasizing the ability of
to survive on dry abiotic surfaces. The air conditioner in the clinical environment is an important but undoubtedly neglected source of
outbreaks, hence, frequent disinfection of hospital air conditioners with appropriate disinfectants is mandatory to mitigate the circulation of
between patients and the hospital environment.
The aim was to adapt the Croatian and the Serbian versions of the Oral Health Impact Profile for the edentulous population (OHIP-EDENT-CRO and OHIP-EDENT-SRB).
The translation and cross-cultural ...adaptation were carried out in accordance with accepted international standards. A total of 95 and 177 removable denture wearers were recruited in Croatia and Serbia respectively. The reliability was evaluated by calculating Cronbach's alpha coefficient and by test-retest (30 participants in each country). The concurrent validity was determined by calculating the Spearman's rank coefficient between the OHIP-EDENT summary scores and one question related to removable denture satisfaction. Construct validity was determined by exploratory factor analysis (EFA). Responsiveness was determined by comparison of the OHIP-EDENT summary scores before and after dental implant placement to support mandibular overdentures (23 patients in Croatia, 21 in Serbia).
Cronbach's alpha coefficient was 0.92 in Croatia and 0.87 in Serbia. The intraclass correlation coefficient was 0.98 in Croatia and 0.94 in Serbia. In Croatia the Spearman's correlation coefficient was -0.71 (p<0.001) and in Serbia -0.74 (p<0.001). Both confirmed concurrent validity. Construct validity was tested by EFA, which extracted four factors in each country, accounting for 66.59% of the variance in Croatia and 59.33% in Serbia. Responsiveness was confirmed in both countries by a significant OHIP-EDENT summary score reduction and a high standardised effect size (3.9 in Croatia, 1.53 in Serbia).
The results prove that both instruments, the OHIP-EDENT-CRO and the OHIP-EDENT-SRB, have very good psychometric properties for assessing OHRQoL in the edentulous population.
As a proxy for pollutants that may be simultaneously present in urban wastewater streams, the effects of two microplastics-polystyrene (PS; 10, 80 and 230 μm diameter) and polymethylmethacrylate ...(PMMA; 10 and 50 μm diameter)-on fertilisation and embryogenesis in the sea urchin
with co-exposure to the pyrethroid insecticide cypermethrin were investigated. Synergistic or additive effects were not seen for plastic microparticles (50 mg L
) in combination with cypermethrin (10 and 1000 μg L
) based on evaluation of skeletal abnormalities or arrested development and death of significant numbers of larvae during the embryotoxicity assay. This behaviour was also apparent for male gametes pretreated with PS and PMMA microplastics and cypermethrin, where a reduction in sperm fertilisation ability was not evidenced. However, a modest reduction in the quality of the offspring was noted, suggesting that there may be some transmissible damage to the zygotes. PMMA microparticles were more readily taken up than PS microparticles, which could suggest surface chemical identity as potentially modulating the affinity of larvae for specific plastics. In contrast, significantly reduced toxicity was noted for the combination of PMMA microparticles and cypermethrin (100 μg L
), and may be related to less ready desorption of the pyrethroid than PS, as well as cypermethrin activating mechanisms that result in reduced feeding and hence decreased ingestion of microparticles.
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