The aim of this study was to identify some of the secondary metabolites present in acetonic, methanolic, and hexanic extracts of lichen Xanthoparmelia stenophylla and to examine their antioxidant, ...antimicrobial, and cytotoxic activity. Compounds of the depsid structure of lecanoric acid, obtusic acid, and atranorin as well as usnic acid with a dibenzofuran structure were identified in the extracts by HPLC. The acetone extract was shown to have the highest total phenolic (167.03 ± 1.12 mg GAE/g) and total flavonoid content (178.84 ± 0.93 mg QE/g) as well as the best antioxidant activity (DPPH IC50 = 81.22 ± 0.54). However, the antimicrobial and antibiofilm tests showed the best activity of hexanic extract, especially against strains of B. cereus, B. subtilis, and S. aureus (MIC < 0.08, and 0.3125 mg/mL, respectively). Additionally, by using the MTT method, the acetonic extract was reported to exhibit a strong cytotoxic effect on the HeLa and HCT-116 cell lines, especially after 72 h (IC50 = 21.17 ± 1.85 and IC50 = 21.48 ± 3.55, respectively). The promising antioxidant, antimicrobial, and cytotoxic effects of Xanthoparmelia stenophylla extracts shown in the current study should be further investigated in vivo and under clinical conditions.
Serological testing is a powerful tool for analyzing the infectious disease burden landscape. Therefore, this study aimed to determine the seroprevalence against SARS-CoV-2 in the population of the ...municipality of Kragujevac, Serbia, with a particular reference to silent infections. A total of 4,804 participants over 19 years of age were randomly sampled for population-based seroprevalence research. Anti-N IgG antibodies were measured using rapid serological tests (UNscience
®
). The population was divided into four Cohorts, according to the history of SARS-CoV-2 infection and vaccination status with the whole inactivated virus vaccine BBIBP-CorV (Vero Cell
®
, Sinopharm), as follows: Cohort I—confirmed SARS-CoV-2 infection, not vaccinated with the BBIBP-CorV vaccine; Cohort II—without confirmed SARS- CoV-2 infection, vaccinated with the BBIBP-CorV vaccine; Cohort III—confirmed SARS-CoV-2 infection, vaccinated with the BBIBP-CorV vaccine; Cohort IV—without confirmed SARS-CoV-2 infection, not vaccinated with the BBIBP-CorV vaccine (silent immunization). Cohorts I and IV included patients vaccinated with vaccines other than the BBIBP-CorV vaccine. The results showed that the overall prevalence of anti-N IgG antibodies was 56.5%, with the highest seroprevalence in Cohort III at 85.8%. In Cohort IV, the prevalence of anti-N IgG antibodies was 40.7%, attributed to silent immunization. The results also suggest that the prevalence of anti-N IgG antibodies decreased over time but remained detectable for more than 12 months in Cohort I. Since currently, there is no data on silent infection frequency in our country, these findings may provide insight into the extent of silent infections in the Serbian population.
With the goal to discover a new antitumor drug with the better or similar effects to existing, a small series of β-diketonate was tested on a cisplatin-resistant MDA-MB-231 and HeLa tumor cell lines, ...and nontumor MRC-5 cell line. All compounds showed notable cytotoxicity against both tumor cell lines and good selectivity. Importantly, β-diketonates displayed greater selectivity than cisplatin, which is the crucial factor for a new antitumor drug candidate. Further, investigations with biomacromolecules such as DNA and serum albumin were performed. Investigations showed that tested compounds bind to DNA through intercalation and have appropriate affinity for binding to bovine serum albumin. In addition, the molecular docking study was performed to investigate more specifically the sites and binding mode of tested β-diketonate to DNA or bovine serum albumin. In conclusion, all results indicated the big potential of these compounds for application in clinical practice in future.
Teucrium polium has been used in traditional medicine around the world for centuries in treatment of various conditions and diseases. Many studies have confirmed pharmacological effects of its ...extracts, although the immunomodulatory effect has not been investigated. Therefore, the aim of our study was to examine the immunomodulatory effect of methanolic extract of T. polium (TPE) on peripheral blood mononuclear cells (PBMCs) derived from healthy donors and patients with hepatitis C virus HCV infection. We analyzed the effect of the extract on PBMCs viability using the MTT test. The cell death type was determined using Annexin V-FITC/7-AAD staining. Immunophenotyping using anti-CD8 FITC, anti-CD4 PE, anti-CD3 ECD, anti-CD20 PC5, anti-CD14 FITC and anti-CD25 PC7 was performed by flow cytometry. Results of the MTT test indicate that TPE stimulates proliferation of healthy PBMCs, while the HCV PBMCs viability was slightly reduced. The percentage of apoptotic HCV PBMCs was higher after TPE treatment compared to the control. The proportion of CD25-expressing cells was higher among the untreated HCV PBMCs than in the untreated healthy PBMCs. TPE treatment significantly and gradually increased CD25 expression in healthy PBMCs, whereas CD25 expression on HCV PBMCs increased only at the highest TPE concentration. The upregulation of double-positive CD3+CD25+, CD20+CD25+ and CD14+CD25+ cells was significant in TPE treated healthy PBMCs, while only the highest concentration was effective on HCV PBMCs. In summary, TPE exerts a strong immunomodulatory effect on healthy PBMCs and, only at the highest concentration, on HCV PBMNCs.
In this paper, a method of parameterisation of a proximal femur model is presented. The created model retains all the anatomical and morphological features of a realistic model. The parametric model ...of the femur, the so-called master model, is defined by establishing a relation between appropriate femoral regions which extend along the parametrically described axis of the femur. An initial 3D model of the femur is segmented from the CT image and further parameterized to a master model with the potential for customization, i.e. for adaptation to patient-specific values using X-ray images, still maintaining precise anatomical consistency. The first step towards the femur customization is the contour extraction of different types of tissues represented in X-ray images. As medical images can be blurry, image processing was carried out and a Canny edge detector operator was applied. The numerical values of the parameters were determined by manual measuring of defined regions on an X-ray image. The variability testing was performed on 12 femurs. The proposed model can greatly contribute to preoperative planning, implant selection, as well as to the overall shortening of intervention time.
Two different enzymes exhibiting 6-phosphofructo-1-kinase (PFK1) activity were isolated from the mycelium of Aspergillus niger: the native enzyme with a molecular mass of 85 kDa, which corresponded ...to the calculated molecular mass of the deduced amino acid sequence of the A. niger pfkA gene, and a shorter protein of approximately 49 kDa. A fragment of identical size also was obtained in vitro by the proteolytic digestion of the partially purified native PFK1 with proteinase K. When PFK1 activity was measured during the proteolytic degradation of the native protein, it was found to be lost after 1 h of incubation, but it was reestablished after induction of phosphorylation by adding the catalytic subunit of cyclic AMP-dependent protein kinase to the system. By determining kinetic parameters, different ratios of activities measured at ATP concentrations of 0.1 and 1 mM were detected with fragmented PFK1, as with the native enzyme. Fructose-2,6-biphosphate significantly increased the Vsubscript max of the fragmented protein, while it had virtually no effect on the native protein. The native enzyme could be purified only from the early stages of growth on a minimal medium, while the 49-kDa fragment appeared later and was activated at the time of a sudden change in the growth rate. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of sequential purifications of PFK1 enzymes by affinity chromatography during the early stages of the fungal development suggested spontaneous posttranslational modification of the native PFK1 in A. niger cells, while from the kinetic parameters determined for both isolated forms it could be concluded that the fragmented enzyme might be more efficient under physiological conditions.
This paper presents the results of simulations, carried out with the Fluent software, for a high speed train moving at 70 m/s for 4 cases: the train configuration without aerodynamic brakes, the ...train configuration with one aerodynamic brake, with two, and with three aerodynamic brakes deployed over the roof of the train. We have determined the braking force per unit area of aerodynamic brakes and compared our results to the results found in literature. Since it is known that the brake panel installed in the first position creates the greatest resistance, while for the brakes in the second and subsequent positions the intensity of resistance decreases, we analyzed the effect of serial interference and determined the contribution of each brake individually to the total braking force, depending on its position.
In this study we modeled a patient specific 3D knee after anterior cruicate
ligament (ACL) reconstruction. The purpose of the ACL reconstruction is to
achieve stability in the entire range of motion ...of the knee and the
establishment of the normal gait pattern. We present a new reconstruction
technique that generates patient-specific 3D knee models from patient?s
magnetic resonant images (MRIs). The motion of the ACL reconstruction
patients is measured by OptiTrack system with six infrared cameras. Finite
element model of bones, cartilage and meniscus is used for determination
stress and strain distribution at different body postures during gait
analysis. It was observed that the maximum effective von Mises stress
distribution up to 8 MPa occurred during 30% of the gait cycle on the
meniscus. The biomechanical model of the knee joint during gait analysis can
provide insight into the underlying mechanisms of knee function after ACL
reconstruction.
In this paper, the levels of twenty one elements (Ag, Al, As, B, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, S, Se, Sr and Zn) in PM10 are presented, as well as SO2 concentration, measured at ...the sampling site in an urban area of the town of Bor (40,000 inhabitants) in eastern Serbia. The sampling site was located in a densely populated city center about 0.65 km away from one of the largest copper mines and copper smelters in Europe. For the first time PM10 was collected using the European standard sampler, during a preliminary campaign in duration of 7 days in early spring 2009. PM10 were sampled on PTFE membrane filters and element concentrations were quantified by GF AAS and ICP AES. Concentration levels and correlations within trace elements, PM10 and SO2 indicated that industrial activities underpinned with meteorological conditions of low wind speed (calm) are the main factors that influence air pollution in a densely populated area. It was evident that both PM10 mass concentration and SO2 concentration once exceeded the daily limit values during a measuring period of seven days. Strong relationship was found between PM10 and Mn, Mg, Ca and B daily average concentrations. On the other hand, SO2 correlated strongly with As, Pb, Cd, Cu and S daily average concentrations. These results confirm the relationship between emissions of SO2 from the Copper Smelter Bor and calm meteorological conditions (wind speed less than 0.5 m/sec) with the concentration levels of carcinogenic substances of arsenic, lead and cadmium in ambient air.
PDF
