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Mining is very important economic activity. However, mining and related industries presents the main threat for environment. Pollution with heavy metals is a significant problem in Eastern Republic of Macedonia. In year 2003 great environmental disaster happened near small town Makedonska Kamenica, when the Sasa tailings dam collapsed and caused an intensive flow of mining waste material through Kamenica River valley and was discharged into Lake Klaimanci. Water from lake is used for irrigation, thus, the pollution assessment of the Lake Kalimanci sediments was made. The major, trace and rare earth element contamination in surficial lake sediments was studied to assess the effects of metalliferous mining activities. The mean concentrations of major elements [wt %] Si 23.5, Al 7.9, Fe 6.6, Mg 1.3, Ca 3.8, Na 1.1, K 2.3, Ti 0.4, P 0.2, Mn 0.6 and trace elements ranged within: Mo 1.0-4.6 mg kg-1, Cu 144.4-1162 mg kg-1, Pb 1874-16300 mg kg-1, Zn 2944-20900 mg kg-1, Ni 21.7-79.3 mg kg-1, Cd 16.5-136 mg kg-1, Sb 0.6-3.6 mg kg-1, Bi 3.0-24,3 mg kg-1 and Ag 1.4-17.3 mg kg-1. Results of rare earth elements (REE) in surficial lake sediments indicated that are tightly related to the catchment geology. The results of the sequential extraction procedure revealed the majority (Cd, Zn, Pb, Ni, Cu and Cd) of investigated toxic metals and all REEs to be strongly bonded to the exchangeable fraction and the rest (As and Mo) to the oxidizable fraction. Regarding to results is evident that heavy metals and REEs are highly bioavailable for living organisms and can seriously affect human health.

The aim of this study was to determine the levels of potentially toxic elements in cultured and wild fish tissues and to assess their risk for human health. For this purpose, sea bass specimens (Dicentrarchus labrax) were sampled in selected fish farm and three other locations along the eastern Adriatic coast. Ranges of element concentrations in sea bass muscles were 1.60-4.46 ppm for As, 0.001-0.079 ppm for Cd, 0.14-49.10 ppm for Cr, 1.38-4.85 ppm for Cu, 0.11-1.31 ppm for Hg, 0.01-0.65 ppm for Pb and 21.9-136.0 ppm for Zn. Mean Cd, Cr, Cu, Hg, Pb, and Zn concentrations in commercially interesting cultured fish samples were below the permissible levels, while mean As values slightly exceed those limits. In wild fishes mean Cd, Cu, Pb and Zn concentrations were below the recommended limits, for As, Cr and Hg the mean values were higher. The smallest cultured sea bass samples showed As, Cr, Pb, and Zn concentrations exceeding the recommended limits but values decreased with fish size. Therefore, the metal concentrations in commercial fishes showed no threat for human consumption.

The aim of the present study was to determine the concentrations of several potentially toxic elements (PTE) in the recent marine sediment of Makirina bay (central Adriatic), which could according to its organoleptic properties be used as a virgin material for medical treatment, wellness and relax purposes. Sediment samples were collected in June and July 2010 from six different sites in the central part of the bay. The range of measured elemental concentrations in analysed surficial sediment were: As (11-15,8 ppm), Cr (61,6 -109,5 ppm), Cu (19,4-54,2 ppm), Pb (16,8-29,6 ppm) and Zn (37-52 ppm). Sediment PTE pollution assessment was performed using contamination factor (CF), contamination degree (Cdeg) and pollution load index (PLI). The calculated environmental index values show a low to moderate contamination status of sediment. Future geochemical investigation on these sediments are necessary prior actual use in various therapeutic treatment.

Natural polymer-based scaffolds are generally considered as favourable matrices for the adhesion and growth of cells in tissue repair. One of the most popular materials in this respect is silk fibroin, known for its wide usage in biomedical applications. This work focuses on the development of electrospun scaffolds based on poly(e-caprolactone) (PCL) and silk fibroin (SF) evaluated regarding the SF effect on their morphology, surface wetting ability, thermal properties, and HaCaT model cell line biocompatibility. The study revealed that the lowest PCL/SF concentration resulted in highest bead-like morphology formation, relatively thick fibers with the presence of random beads in the case of PCL, while uniform and thinner fibers in the case of increasing PCL/SF content scaffolds. The addition of SF reduced the degree of crystallinity in the PCL due to the less organized crystal structure, and decreased its thermal stability. Both SEM and MTT analyses showed cell presence on all scaffolds three days after cell seeding. Although SF improved PCL hydrophilicity, as shown quantitatively by the MTT assay for improved cytocompatibility properties, more structured electrospun PCL/SF scaffold strategies are required. [ABSTRACT FROM AUTHOR]

The presence of potentially toxic elements (PTE) was determined in different tissues of five selected marine organisms. The As, Cd, Cu, Mn, Mo, Ni, Pb and Zn concentrations were measured in the seagrass Cymodocea nodosa , the green alga Cladophora echinus , the red alga Gelidiella lubrica , the marine topshell Phorcus turbinatus and the littoral crab Carcinus aestuarii , as well as in seawater from Makirina Bay. The levels of As, Cd, Cu, Mn and Zn in the biota were found to exceed those in previously analysed sediments, indicating the bioaccumulation of these PTE. The biota-sediment accumulation factor (BSAF) and concentration factor (CF) varied among different organisms. As regards the five selected species, C. nodosa , C. echinus and G. lubrica proved to be the strongest accumulators of Mn, while P. turbinatus and C. aestuarii showed a high capacity to accumulate As, Cd, Cu and Zn. These species can be considered as good ecological indicators in the assessment of PTE pollution in marine littoral environments. [ABSTRACT FROM AUTHOR]

Stable isotope composition of carbon and nitrogen in the sediment and pore water of a eutrophic freshwater lake was studied. Based on changes in the delta 13C and delta 15N values of dissolved components and sediment fraction, possible processes involved in the decompositionof sedimentary organic matter are outlined. The relative importance of acetate fermentation and CO2 reduction was estimated using known mathematical models, and ammonia assimilation by methanogenic bacteria is hypothesised to be the main process governing the isotope fractionation of dissolved nitrogen in pore water. [ABSTRACT FROM AUTHOR]

Background: Limbal stem cells (LSCs) are crucial for the regeneration of the corneal epithelium in patients with limbal stem cell deficiency (LSCD). Thus, LSCs during cultivation in vitro should be in highly homogeneous amounts, while potency and expression of stemness without tumorigenesis would be desirable. Therefore, further characterization and safety evaluation of engineered limbal grafts is required to provide safe and high-quality therapeutic applications., Methods: After in vitro expansion, LSCs undergo laboratory characterization in a single-cell suspension, cell culture, and in limbal grafts before transplantation. Using a clinically applicable protocol, the data collected on LSCs at passage 1 were summarized, including: identity (cell size, morphology); potency (yield, viability, population doubling time, colony-forming efficiency); expression of putative stem cell markers through flow cytometry, immunofluorescence, and immunohistochemistry. Then, mitotic chromosome stability and normal mitotic outcomes were explored by using live-cell imaging. Finally, impurities, bacterial endotoxins and sterility were determined., Results: Expression of the stemness marker p63 in single-cell suspension and in cell culture showed high values by different methods. Limbal grafts showed p63-positive cells (78.7 ± 9.4%), Ki67 proliferation (41.7 ± 15.9%), while CK3 was negative. Impurity with 3T3 feeder cells and endotoxins was minimized. We presented mitotic spindles with a length of 11.40 ± 0.54 m and a spindle width of 8.05 ± 0.55 m as new characterization in LSC culture. Additionally, live-cell imaging of LSCs (n = 873) was performed, and only a small fraction < 2.5% of aberrant interphase cells was observed; 2.12 ± 2.10% of mitotic spindles exhibited a multipolar phenotype during metaphase, and 3.84 ± 3.77% of anaphase cells had a DNA signal present within the spindle midzone, indicating a chromosome bridge or lagging chromosome phenotype., Conclusion: This manuscript provides, for the first time, detailed characterization of the parameters of fidelity of the mitotic process and mitotic spindle morphologies of LSCs used in a direct clinical application. Our data show that p63-positive CK3-negative LSCs grown in vitro for clinical purposes undergo mitotic processes with extremely high fidelity, suggesting high karyotype stability. This finding confirms LSCs as a high-quality and safe therapy for eye regeneration in humans., (© 2023. The Author(s).)

Since only few reported studies propose anti-vascular endothelial growth factor (anti-VEGF) delivery through electrospun scaffolds, this study greatly contributes to the potential prevention of patient's vision loss, as it explores electrospun polycaprolactone (PCL) coated with anti-VEGF for the blockage of abnormal cornea vascularization. In terms of physicochemical properties, the biological component increased the PCL scaffold fiber diameter (by ~24%) and pore area (by ~82%), while ut slightly reduced its total porosity as the anti-VEGF solution filled the voids of the microfibrous structure. The addition of the anti-VEGF increased the scaffold stiffness almost three-fold at both strains of 5 and 10%, as well as its biodegradation rate (~36% after 60 days) with a sustained release profile after Day 4 of phosphate buffered saline incubation. In terms of scaffold application function, the PCL/Anti-VEGF scaffold proved to be more favorable for the adhesion of cultured limbal stem cells (LSCs); this was confirmed by the SEM images, where the cells showed flat and elongated conformations. Further support of the LSC growth and proliferation was confirmed by the identified p63 and CK3 markers after cell staining. These results demonstrate the advantageous effect of the surface-adsorbed anti-VEGF to stop vision loss and help damaged corneal tissue repair.