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Making science enjoyable inspires students to learn more. Out-of-class activities such as science fairs and Olympiads, serve as reasonable informal learning environments that demand attention. The association of students’ involvement in these activities with increased student interest in science followed by the selection of science-related careers, should motivate all in-charge stakeholders. In this work, we analysed the outcomes of the Bosnia Science Olympiad (BSO) as the first national Science Olympiad in Bosnia and Herzegovina (BiH), aiming the improvement of science education and bringing different ethnic groups under the umbrella of science, in a post-conflict area. The two-day endeavour held in Sarajevo includes competition in four science-related categories (Environment, Engineering, Have an Idea, Web Design) and social activities. In this work, the comprehensive data, including participants’ gender, their ethnic background, cities, schools, and supervisors, over five years, was analysed. The number of participating high-school students increased from 78 to 143, of supervisors from 21 to 95, and of schools from 7 to 15, reaching a wide demographic acceptance to cover all ethnic regions in BiH. The relationship between gender and the selection of a category, shows bias of male participants towards Web Design (21%) and Engineering (40%), and of female students towards “Have an Idea” (40%) and Environment (44%) categories. The contribution of BSO choosing a science career, getting socialized without prejudices, and the improvement of students’ self-confidence, were as well addressed. Our work demonstrates a model work to successfully promote science in post-conflict settings.

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ATR-FTIR Spectroscopy of aqueous cell culture samples is explained step-by-step. Infrared spectra acquisition, processing and analysis is included briefly.

The myosin II motors are ATP-powered, force-generating machines driving cardiac and muscle contraction. Myosin II heavy chain isoform- beta (beta-MyHC) is primarily expressed in the ventricular myocardium and slow-twitch muscle fibers, such as in M. soleus. M. soleus-derived myosin II (SolM-II) is often used as an alternative to the ventricular beta-cardiac myosin (beta M-II); however, the direct assessment of detailed biochemical and mechanical features of the native myosins is limited. By employing the optical trapping method, we examined the mechanochemical properties of the native myosins isolated from rabbit heart ventricle and M. soleus muscles at the single-molecule level. Contrary to previous reports, the purified motors from the two tissue sources, despite the same MyHC isoform, displayed distinct motile and ATPase kinetic properties. Beta M-II was nearly threefold faster in the actin filament-gliding assay than SolM-II. The maximum acto-myosin (AM) detachment rate derived in single-molecule assays was threefold higher in beta M-II. The stroke size for both myosins was comparable. The stiffness of the AM rigor cross-bridge was also similar for both the motor forms. The stiffness of beta M-II was found to be determined by the nucleotide state of the actin-bound myosin. Our analysis revealed distinct kinetic differences, i.e., a higher AM detachment rate for the beta M-II, corresponding to the ADP release rates from the cross-bridge, thus elucidating the observed differences in the motility driven by beta M-II and SolM-II. These studies have important implications for the future choice of tissue sources to gain insights into cardiomyopathies

The innate immune response triggered by CpG DNA can improve host survival following pathogen challenge. Whether CpG ODN-mediated immune activation leads to global molecular changes in cells that are detectable by FTIR spectroscopy is currently unknown. Here, we used Attenuated Total Reflectance (ATR) Fourier Transform Infrared (FTIR) spectroscopy to monitor the molecular changes in murine macrophage RAW 264.7 cells upon activation with CpG DNA and lipopolysaccharide (LPS). By PCA analysis, we identified the sources of variation to follow with detailed spectral analysis. CpG DNA and LPS treatment increase the total nucleic acid concentration from the early periods post-activation, and DNA synthesis follows RNA synthesis. RNA-specific peak shows the activation state of macrophages in early periods post-treatment. CpG DNA and LPS result in an initial rapid increase in the total protein concentration, leveling off two hours post-activation. Both activated groups increase the concentration of fatty acids, triglycerides, and cholesterol, pointing out to a shared synthesis pathway and de novo lipogenesis. This study, for the first time, demonstrates the use of FTIR spectroscopy as an independent modality to monitor the activation dynamics of murine macrophages upon activation with CpG DNA and LPS.

No abstract

Glucosylceramidase (GCase) is a lysosomal enzyme that catalyzes the cleavage of β-glucosidic linkage of glucocerebroside (GC) into glucose and ceramide; thereby, plays an essential function in the degradation of complex lipids and the turnover of cellular membranes.The growing list of 460 mutations in the gene coding for it—glucosylceramidase beta acid 1 (GBA1)—is reported to abolish its catalytic activity and decrease its enzyme stability, associating it with severe health conditions such as Gaucher disease (GD), Parkinson Disease and Dementia with Lewy bodies.Although the three-dimensional structure of wild type glucosylceramidase is elucidated, little is known about its features in human cells. Moreover, alternative sources of GCase that prove to be effective in the treatment of diseases with enzyme treatment therapies, impose the need for simple and cost-effective procedures to study the enzyme behaviour. This work, for the first time, shows a well established, yet simple, cost- and time-efficient protocol for the study of GCase enzyme in human leukocytes by the artificial substrate PNPG. Characterization of the enzyme in human leukocytes for activation parameters (optimal pH, Km, and Vmax) and enzyme inhibition, was done. The results indicate that the optimum pH of GCase enzyme with PNPG is 5.1. The Km and Vmax values were 12.6mM and 333 U/mg, respectively. Gluconolactone successfully inhibits GCase in a competitive manner, with a Ki value of 0.023 mM and IC 50 of 0.047 mM. Glucose inhibition was uncompetitive with a Ki of 1.94 mM and IC50 of 55.3 mM. This is the first report for the inhibitory effect of glucose, δ-gluconolactone on leukocyte GCase activity.