In today's world, many companies have employees from different countries, and they work together as virtual teams using technology. The leaders of these teams need to know how to manage their teams well, understand their unique skills and overcome challenges. Accordingly, we want to study the specific leadership style and its effects on virtual teams' success. Data for the study was collected from various companies that have online activities. Team members participated in surveys, providing information on how their leaders effectively motivated them to be productive and satisfied in their jobs. Additionally, the surveys examined team members' knowledge-sharing levels in their leaders and organizations. Based on the analyses, we found that transformational leadership positively affects virtual team performance but not knowledge sharing; however, knowledge sharing positively improves team performance.

SUMMARY Inflammation, axonal loss and demyelinating plaques in the brain, which are the background of multiple sclerosis, very often cause changes in speech or dysarthria, in a range from mild to so severe that they impair comprehension of speech by the interlocutor. As a consequence of multiple sclerosis, dysphagia can also occur. The aim of this paper is to present the speech and swallowing difficulties that result from multiple sclerosis, and the importance of assessing the speech and swallowing in people with multiple sclerosis. This article is descriptive and provides a comprehensive overview of the literature dealing with this topic. Speech difficulties impede daily functioning and are often the first sign that other people notice. Swallowing difficulties not only complicate daily life but, if not given sufficient attention, are a possible life-threatening consequence of multiple sclerosis. Assessment of speech and swallowing difficulties should be part of the clinical assessment in each person with multiple sclerosis. As multiple sclerosis progresses, so do speech and swallowing difficulties, and it is of utmost importance to provide appropriate treatment that can alleviate these difficulties. Speech-language pathologists should be part of a team making the diagnosis and providing treatment for a person with multiple sclerosis.

SUMMARY The municipality of Bogatić, part of Mačva District, belongs to the Pannonian Basin, where high concentrations of arsenic in artesian wells were detected. Numerous epidemiological studies have confirmed the association of exposure to arsenic in drinking water and bladder cancer (C67). This retrospective ten-year analysis included age-standardized incidence rates (ASRs) and age-specific incidence rates of C67 in the municipality of Bogatić and rural municipalities of Mačva District. The concentration of arsenic in drinking water was determined at Šabac Public Health Institute (PHI) laboratories in 2015. ASRs were estimated using data from regional cancer registries at Šabac PHI and compared by use of the Mann-Whitney U test. Control population was recruited from an area where there were no artesian wells or hydrogeological conditions that would indicate elevated concentrations of arsenic in drinking water. Arsenic levels in all artesian wells in Bogatić municipality were 1.4 to 41 times higher than the maximum permissible concentration (mean 120 µg/L±165). Female subjects from Bogatić municipality had higher ASRs of C67 compared with the populations in rural municipalities of Mačva District (p<0.01), while the incidence of bladder cancer was by 13% greater than that in central Serbia (standardized incidence ratio, 113; 95% CI 96.97-131.35). Male subjects from Bogatić municipality had higher ASRs of C67 but the difference was not statistically significant (p>0.05). Our analyses suggested that exposure to arsenic in drinking water could triple the risk of bladder cancer. These results support the conclusions of previous studies that there may be an association between higher concentrations of arsenic in drinking water and higher ASRs of bladder cancer in both male and female subjects.

SUMMARY Here we report a case of a 5-year-old boy with Ebstein anomaly and supraventricular tachycardia. He was diagnosed with Ebstein anomaly at the age of 3 months during the workup for afebrile convulsions, and has been followed by a pediatric cardiologist since. Electrocardiography recorded a small Rr` pattern in V1 on a few occasions, without other abnormalities. At the age of 2.5 years, the first episode of supraventricular tachycardia was recorded and stopped with adenosine. He was started on atenolol and was asymptomatic until a year later when he presented with the second recorded supraventricular tachycardia. He was referred to our institution for an electrophysiology study with ablation. Tachycardia was entrained and all the maneuvers were in accordance with atrioventricular reentry tachycardia. Tricuspid annulus was mapped during tachycardia. The earliest atrial signals appeared in the posteroseptal region of the valve, mechanical blocking of the tachycardia was recorded in that region, and early fractionated signal was present during ventricular retrograde pacing. The pathway was successfully ablated. Basal electrocardiogram was without change after ablation and the patient did not experience recurrence of tachycardia during follow-up. This case shows the efficacy and importance of ablation in Ebstein anomaly, without x-ray or intracardiac echocardiography.

SUMMARY Regular physical activity and maintaining fitness reduce the risk of chronic cardiovascular and metabolic diseases, reduce the risk of exacerbation of existing diseases, maintain physical and mental health, and contribute to healthy and successful aging in the elderly. It is of particular importance during the prolonged COVID-19 pandemic. The aim of this review is to present relevant knowledge about the effects of restrictions and social distancing established with the aim of suppressing the COVID-19 pandemic, on physical activity and mental health of elderly people. During the pandemic, numerous authors have reported a decrease in the share of physically active population and those that used to exercise regularly. The time spent in activity decreases, energy expenditure decreases, and the time spent sedentary increases although the results in all segments related to physical activity are not consistent. Lockdown measures significantly worsen insomnia, sleep quality, feelings of loneliness, anxiety and depression in older people, especially in women. During the restrictive measures caused by the COVID-19 pandemic, physical activity and exercise significantly contribute to the maintenance and improvement of physical and mental health.

Background and Objectives: Differentiating between a high-grade glioma (HGG) and solitary cerebral metastasis presents a challenge when using standard magnetic resonance imaging (MRI) alone. Magnetic resonance spectroscopy (MRS), an advanced MRI technique, may assist in resolving this diagnostic dilemma. N-acetylaspartate (NAA), an amino acid found uniquely in the central nervous system and in high concentrations in neurons, typically suggests HGG over metastatic lesions in spectra from ring-enhancing lesions. This study investigates exceptions to this norm. Materials and Methods: We conducted an MRS study on 49 histologically confirmed and previously untreated patients with brain metastases, employing single-voxel (SVS) techniques with short and long echo times, as well as magnetic resonance spectroscopic imaging (MRSI). Results: In our cohort, 44 out of 49 (90%) patients demonstrated a typical MR spectroscopic profile consistent with secondary deposits: a Cho peak, very low or absent Cr, absence of NAA, and the presence of lipids. A peak at approximately 2 ppm, termed the “NAA-like peak”, was present in spectra obtained with both short and long echo times. Among the MRS data from 49 individuals, we observed a peak at 2.0 ppm in five brain metastases from mucinous carcinoma of the breast, mucinous non-small-cell lung adenocarcinoma, two metastatic melanomas, and one metastatic non-small-cell lung cancer. Pathohistological verification of mucin in two of these five cases suggested this peak likely represents N-acetyl glycoproteins, indicative of mucin expression in cancer cells. Conclusions: The identification of a prominent peak at 2.0 ppm could be a valuable diagnostic marker for distinguishing single ring-enhancing lesions, potentially associated with mucin-expressing metastases, offering a new avenue for diagnostic specificity in challenging cases.

Beakground: The prevalence of cardiovascular diseases in COVID-19 patients, such as hypertension, diabetes mellitus, and chronic obstructive pulmonary disease, which are the most common comorbid conditions in COVID-19 patients, is considered a risk factor for premature mortality in the population. The aim of the study is to compare the standard biochemical and hematological markers of COVID-19 patients on mechanical ventilation and those who have recovered, and to identify differences by gender and comorbidities, as well as the dominant marker in comorbidities that frequently shows statistical significance, in order to investigate its prognostic value in further research. METHODS The study is a retrospective study of patients with RT-PCR confirmed presence of the Sars-CoV-2 virus who were hospitalized at the Zenica Cantonal Hospital. The study lasted from February to April 2021. RESULTS The results of the study, which included a sample of 302 participants, indicate that men were more represented in both the mechanical ventilation group and the recovered group, with 59.6% compared to women with 40.4%. Among the investigated biochemical and hematological parameters, there was a significantly higher number of leukocytes, urea, creatinine, LDH, and troponin in patients on mechanical ventilation, while the number of platelets was significantly higher in recovered patients. The most common comorbidity was hypertension in both groups of patients, with 24.5%. In patients on mechanical ventilation with cardiovascular disease, there was a significantly higher number of leukocytes, urea, creatinine, LDH, and troponin. In the same patients with three comorbidities, there was a significantly higher number of leukocytes, troponin, and LDH, while recovered patients without comorbidities had a significantly higher number of platelets. CONCLUSIONS The male gender and comorbidities remain a vicious circle in COVID-19 infection, while biochemical and hematological markers can help in forecasting and improve the clinical treatment of these high-risk patients.

Background: this study aimed to determine the expression of RNA-binding oncofetal proteins IMP3 and LIN28A in extravillous (EVT) and villous trophoblast (VT) cells of placentas from pre-eclamptic (PE) pregnancies to better understand the pathogenesis of PE. Methods: placental tissue of 10 patients with PE with severe features, 10 patients with PE without severe features and 20 age-matched healthy pregnancy controls were analyzed by immunohistochemistry, double immunofluorescence and qPCR. Results: We found a decreased percentage of IMP3-positive EVT cells in PE with and without severe features compared to that of the healthy control (p < 0.001). IMP3 expression was significantly low in VT of PE placentas compared to that of the healthy control (p = 0.002). There was no significant difference in LIN28A expression between groups of PE and the control group. Additionally, we noticed the trend toward downregulation of IMP3 mRNA and LIN28A mRNA in severe PE compared to that of healthy controls. Conclusions: We demonstrated that IMP3 expression is decreased in EVT and VT cells of placentas from pregnancies complicated with both PE with and without severe features. However, additional functional investigations are needed to clarify the role of IMP3 as a potential therapeutic target in the management of PE.

The gradual deterioration of articular cartilage was thought to be the central event in osteoarthritis (OA), but recent studies demonstrated the importance of low-grade synovitis in the progression of OA. The Syndecan (SDC) family of membrane proteoglycans is known to be involved in the regulation of inflammation, but there is limited evidence considering the role of syndecans in OA synovitis. Our study aimed to investigate the hip OA synovial membrane expression patterns of SDC1, SDC2 and SDC4, as well as exostosins and sulfotransferases (enzymes involved in the polymerisation and modification of syndecans’ heparan sulphate chains). Synovial membrane samples of patients with OA (24) were divided into two groups according to their Krenn synovitis score severity. The immunohistochemical expressions of SDC1, SDC2, SDC4, EXT1, EXT2, NDST1 and NDST2 in synovial intima and subintima were then analysed and compared with the control group (patients with femoral neck fracture). According to our study, the immunoexpression of SDC1, NDST1 and EXT2 is significantly increased in the intimal cells of OA synovial membrane in patients with lower histological synovitis scores and SDC4 in patients with higher synovitis scores, in comparison with non-OA controls. The difference in the expression of SDC2 among the OA and non-OA groups was insignificant. SDC1, SDC4, NDST1 and EXT2 seem to be involved as inflammation moderators in low-grade OA synovitis and, therefore, should be further investigated as potential markers of disease progression and therapeutic goals.

The subject of this research wasto verify the feasibility of implementing green chemistry principles within the business company „Omorika Reciklaža“ Ltd. situated in Johovac near Doboj, Bosnia and Herzegovina. The objective of this study wasto conduct a detailed assessment of the company's facilities and operations, using environmental audits, to identify technological processes (production lines), energy and waste flows, capacities, product range, and other pertinent factors crucial for theapplication of green chemistry principles. Special emphasis was placed on analyzing each substance that constitutes a raw material, whether used individually or as part of mixtures.The assessment of safety data sheets involvedutilizing the CAS registration numbers of substances from the Chemical Abstracts Service, cross-referenced with the ECHA database (European Chemicals Agency). The outcomes, attained through an exhaustive analysis of each substance, were presented as a "chemical inspection" of the company. Through the analysis of all substances and mixtures in the technological process (chemical inspection), as well as the capacity of production flows, energy and resource flows, wastewater, and waste, the potential for enhancing the technological process wasidentified. This involvedreducing dust levels in the workspace, decreasing electricity consumption (utilizing renewable sources), and substituting particularly hazardous chemicals used in the technological process. KEYWORDS:green chemistry; chemical safety; SVHC;environmentalaudit

In accordance with consumer requirements, the water must be adequately purified, and the corresponding parameters within the defined values. Various methods are used for this purpose, of which the ion exchange method can be highlighted as the simplest, most efficient and economically profitable. Ion exchange is a reversible process of ion exchange between a solid phase and an electrolyte solution. The ion exchanger is a macromolecular insoluble material that has chemically bound electrified groups and mobile, oppositely charged ions that compensate for this electrification. Ion exchangers are usually used in the form of compact or granular beds that fill the column through which the solution with the ions to be exchanged flows.They usually contain phenolic, carboxylic, sulfonic amino and other groups, which is why the treatment also results in decarbonization, softening, demineralization and denitrification of water. As the assessment of water quality is based on the most significant physico-chemical parameters, the aim of the work is the analysis of drinking water before and after treatment with an ion exchanger.For this purpose, organoleptic parameters such as smell, taste and color were first analyzed. After that, physico-chemical parameters were analyzed: pH values, electrical conductivity, m-alkalinity, p-alkalinity, water hardness, organic matter content, chloride content, iron and manganese content. An ion exchanger based on resin was used, which after use was regenerated by washing with NaClsolution.The analysis of the water sample, before and after the ion exchange treatment, showed that the treatment process was effective and that the decarbonization and softening of the water was carried out, whereby the water was categorized as soft water (water <9⁰dH).The analyzed water is tasteless, odorless and colorless before and after treatment. The results of the analysis showed that all the values of the analyzedphysico-chemical parametersare in accordance with the Rulebook on the Healthiness of Drinking Water(Official Gazetteof Federation of Bosnia and Herzegovina No.40/10) arebelow the maximum allowed values. KEYWORDS:water, ion exchange, physical-chemical parameters; water treatment

Background: Post-acute sequelae of SARS-CoV-2 infection (PASC) is a complicated disease that affects millions of people all over the world. Previous studies have shown that PASC impacts 10% of SARS-CoV-2 infected patients of which 50–70% are hospitalised. It has also been shown that 10–12% of those vaccinated against COVID-19 were affected by PASC and its complications. The severity and the later development of PASC symptoms are positively associated with the early intensity of the infection. Results: The generated health complications caused by PASC involve a vast variety of organ systems. Patients affected by PASC have been diagnosed with neuropsychiatric and neurological symptoms. The cardiovascular system also has been involved and several diseases such as myocarditis, pericarditis, and coronary artery diseases were reported. Chronic hematological problems such as thrombotic endothelialitis and hypercoagulability were described as conditions that could increase the risk of clotting disorders and coagulopathy in PASC patients. Chest pain, breathlessness, and cough in PASC patients were associated with the respiratory system in long-COVID causing respiratory distress syndrome. The observed immune complications were notable, involving several diseases. The renal system also was impacted, which resulted in raising the risk of diseases such as thrombotic issues, fibrosis, and sepsis. Endocrine gland malfunction can lead to diabetes, thyroiditis, and male infertility. Symptoms such as diarrhea, nausea, loss of appetite, and taste were also among reported observations due to several gastrointestinal disorders. Skin abnormalities might be an indication of infection and long-term implications such as persistent cutaneous complaints linked to PASC. Conclusions: Long-COVID is a multidimensional syndrome with considerable public health implications, affecting several physiological systems and demanding thorough medical therapy, and more study to address its underlying causes and long-term effects is needed.