BACKGROUND During the COVID-19 pandemic many people experienced psycho-social stress which affected their sleep. This study was conducted during the third and fourth epidemic wave when international borders of Serbia and Bosnia-Herzegovina were entirely open, no curfew or wearing face masks were imposed, but the highest rates of COVID-19-related fatalities were reported. The aim of this study was to examine sleep patterns with COVID-related stress during the pandemic. METHODS Anonymous paper questionnaires were distributed from September 2020 to October 2021 across 8 cities in Serbia and Republic of Srpska (Bosnia and Herzegovina). Socio-epidemiologic characteristics, the COVID Stress Scales-CSS and the Perceived Stress Scale were administered. Sleeping patterns before and during the COVID-19 pandemic (bedtime, time spent sleeping and sleep quality) were recorded. RESULTS Responses of 2,301 participants suggested that bedtime after midnight before and during the pandemic did not differ (13.4% vs. 14.8%, respectively). Most participants reported similar length of sleep before and during the pandemic (around 7 h), although 11% of them reported that during the pandemic they slept more often compared to pre-pandemic sleeping schedule. There was an increase in prevalence of poor sleep quality during the pandemic (4.5% vs. 9.4%, respectively). Sleeping more often compared to pre-pandemic sleeping schedule and poor sleep quality during the pandemic were independently associated with a higher CSS. CONCLUSION Proportion of people who reported poor sleep quality doubled in the pandemic. Optimizing sleep quality in crises among people who experience poor sleep quality should be prioritized when managing public health emergencies.

Background: The clinical course of COVID-19 is highly variable, ranging from asymptomatic infection to critical illness with hyperinflammation and multiorgan failure. Oxidative stress plays a central role in COVID-19 pathogenesis, and genetic polymorphisms in glutathione S-transferase (GST) enzymes, particularly GSTM1 and GSTT1 null genotypes, may impair antioxidant defense and exacerbate inflammatory responses. This study aimed to investigate the association of GSTM1 and GSTT1 null genotypes with both disease severity and serum cytokine levels in hospitalized COVID-19 patients. Methods: This cross-sectional study enrolled 137 COVID-19 patients hospitalized during the second pandemic wave (July–September 2020). Patients were stratified into mild (n = 67) and severe (n = 70) groups based on clinical criteria. GSTM1 and GSTT1 polymorphisms were determined by multiplex polymerase chain reaction. Serum levels of 13 cytokines were measured using flow cytometry. Logistic regression analyzed genotype associations with disease severity, and multivariate linear regression assessed relationships between null genotypes and pro-inflammatory cytokine levels (IL-6, TNF-α, IL-17A, IFN-γ), adjusted for age, sex, hypertension, and diabetes. Results: The GSTT1 null genotype was significantly associated with severe COVID-19 (adjusted OR = 2.56, 95% CI: 1.08–6.07, p = 0.032). Severe patients exhibited significantly elevated levels of IL-6 (75.6% increase, p = 0.008), TNF-α (69.4% increase, p = 0.005), IL-17A (54.4% increase, p = 0.016), and IFN-γ (10.1% increase, p = 0.021). Both GSTM1 and GSTT1 null genotypes were associated with higher levels of these cytokines, with stronger effects observed for GSTT1 null. In multivariate analysis, GSTT1 null independently predicted elevated IL-6 (β = 52.6, p = 0.003), TNF-α (β = 13.8, p = 0.002), IL-17A (β = 2.4, p = 0.001), and IFN-γ (β = 56.4, p = 0.012). The combined both null genotype showed the strongest associations but was limited by small sample size (n = 10) and should be interpreted with caution. Conclusions: The GSTT1 null genotype is associated with severe COVID-19 and appears to be associated with heightened pro-inflammatory cytokine responses, particularly IL-6, TNF-α, IL-17A, and IFN-γ. These findings suggest a potential role for genetic impairment of antioxidant defense may contribute to hyperinflammation in COVID-19 hyperinflammation, although validation in larger cohorts is needed.

Atrial fibrillation (AF) is the most common persistent cardiac arrhythmia in clinical practice and a significant, often underdiagnosed risk factor for stroke. The electrocardiogram (ECG) is the primary method for its detection, typically manifesting as irregular $\mathbf{R R}$ intervals and the absence of P-waves. Numerical ECG parameters enable quantitative analysis of these changes and provide a foundation for the development of automated detection systems. This study examines the association between atrial fibrillation and numerical ECG parameters using the ECG-ViEW II database. From 12-lead ECG recordings, key temporal and morphological parameters were extracted, and descriptive statistics were calculated to form the final dataset. Descriptive statistical analysis, inferential tests, and graphical visualizations were applied to compare AF and non-AF groups. The results indicate that parameters describing RR-interval variability show a strong association with atrial fibrillation, confirming their potential for application in automated systems for early AF detection.

<p><strong>Introduction.</strong> Point-of-care ultrasound (POCUS) is increasingly recognized as an extension of the physical examination, enhancing bedside diagnostic accuracy and real-time clinical decision-making. Although widely integrated into medical education and practice internationally, its routine implementation in Bosnia and Herzegovina remains inconsistent and structurally constrained. This study aimed to identify key motivators for POCUS utilization and to examine systemic and organizational barriers limiting its broader adoption in primary and secondary healthcare settings.<br /><strong>Methods. </strong>A cross-sectional study was conducted using two structured anonymous questionnaires administered to physicians attending an ultrasound training course during the &ldquo;Dom zdravlja&rdquo; Doboj symposium in September 2025. After data cleaning, 41 fully completed questionnaires were included in the motivation analysis (general practitioners n = 11; specialists n = 30), and 43 were included in the barriers analysis. The instruments assessed professional characteristics, self-reported ultrasound familiarity, motivators, perceived barriers, and institutional support. Descriptive statistics were applied, with &chi;&sup2; and Fisher&rsquo;s exact tests used for subgroup comparisons (p &lt; 0.05).<br /><strong>Results.</strong> Respondents demonstrated strong motivation for POCUS use, particularly for rapid diagnostic clarification and disease monitoring. Most participants supported formal curricular integration and recognized the professional value of ultrasound practice. Major barriers included insufficient structured training, lack of mentorship, limited access to ultrasound devices, time constraints, absence of clear institutional guidelines, and the need for financial recognition. No significant differences were observed between general practitioners and specialists.<br /><strong>Conclusion.</strong> Physicians in Bosnia and Herzegovina show high motivation toward POCUS adoption. However, implementation is predominantly hindered by systemic and institutional barriers. Coordinated educational, infrastructural, and policy-level interventions are necessary to enable sustainable integration into routine clinical practice.</p>

Background: Undernutrition disorder is a prevalent comorbidity (up to 25%) in type 2 diabetes (T2D) patients which significantly compromises their health. We aimed to assess the association between single nucleotide polymorphysms (SNPs) adiponectin (ADIPOQ) +276 (G/T) and resistin (RETN) −420 (C/G) with the risk of developing T2D and undernutrition in patients with T2D. Methods: The research was conducted as prospective case-control study among 106 patients with T2D and 106 healthy control individuals in the territory of the Bosnia and Herzegovina from Sep 1st 2022 to May 1st 2023. For assessing the nutritional status, the mini nutritional assessment (MNA) was used. DNA analysis was carried out by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) method. The data were analyzed using chi-square test, t-test for independent samples and binary multivariate logistic regression. Results: The research included 212 subjects of which 124 (58.5%) were male. The mean age of the subjects was 68.48±4,67 yr. Almost 20% of subjects were undernourished, significantly more T2D patients when compared to controls (33% vs. 6.6%; P<0.001). ADIPOQ +276 GT genotype was identified as significant predictor of T2D (OR: 3.454; 95% CI: 1.400–8.521; P=0.007) and undernutrition disorder (OR: 3.453; 95% CI: 1.331–8.961; P=0.011) in T2D population, while the presence of RETN −420 CG genotype had protective effect against occurrence of T2D (OR: 0.353; 95% CI: 0.144–0.867; P=0.023). However, RETN genotypes were not associated with undernutrition disorder. Conclusion: ADIPOQ +276 gene polymorphism represent a significant predictor for development of T2D and undernutrition disorder in T2D population, while RETN −420 gene polymorphism was identified as a significant factor associated with a reduced risk for T2D, but was not associated with undernutrition.

Because of the COVID-19 pandemic, people were recommended to implement new health behaviors into their daily routines to prevent the viral spread. The aim of this study was to investigate whether specific health behaviors, such as wearing face masks, taking immunity boosters and visiting risky places were associated with a higher level of stress due to COVID-19 in the general adult population. This cross-sectional study was conducted from September 1, 2020 to October 1, 2021 in eight randomly chosen cities of two Serbian speaking countries (Republic of Serbia and Republic of Srpska - Bosnia and Herzegovina). Participants filled a socio-epidemiologic questionnaire, COVID Stress Scales (CSS) and the Perceived Stress Scale (PSS). The study included 2,301 participants with an average age of 36.72 ± 13.82 years of whom 54.9% were female (p = 0.001). Most participants were healthy, highly educated, employed, married, non-smokers and consumed alcohol. The mean total CSS score was 32.7 ± 23.8 out of 144, suggesting a relatively low stress due to COVID-19. The mean PSS was 19.43 ± 5.05 out of 40 indicating slightly increased level of general stress. Participants who reported higher CSS scores were more likely to wear face masks, use immunity boosters, go to cafes and clubs, have chronic illnesses, have suspicious, but not proven contact with COVID-19 positive people, and use multiple sources of information about COVID-19. Few participants experienced high levels of stress due to COVID-19. People who used face masks, immunity boosters and visited risky places reported a higher level of stress during the pandemic.

<p style="text-align: justify;">The growing trend of securing private industry funding for biomedical research, particularly from pharmaceutical and medical device companies, has raised significant ethical concerns. Since the 1980s, private industry has become the primary funder of biomedical research, surpassing government funding in the U.S. and other developed countries. This shift introduces potential ethical violations, including hidden conflicts of interest, data manipulation, disregard for ethical guidelines, non-disclosure of negative results, and compromised research independence. These issues can undermine research integrity, compromise patient safety, and erode public trust in scientific findings. Effective measures to prevent ethical violations include strengthening transparency, enhancing research independence, promoting ethical education, and reinforcing regulatory frameworks. By fostering open dialogue, implementing stringent disclosure requirements, and ensuring independent oversight, participants can uphold ethical standards in sponsored research. Addressing these challenges is essential to maintaining the credibility of biomedical research, protecting participant rights, and ensuring that research outcomes reliably contribute to evidence-based medicine and public health.</p>

In contrast to electromagnetic fields, static magnetic fields (SMFs) have not been extensively studied in terms of their potential health consequences. Although upward- and downward-oriented magnetic poles may cause various biological effects, only the pole with the upward orientation has been mainly investigated. Considering that the interaction of antigen-presenting cells (APCs) and T lymphocytes is crucial to trigger an immune response, we assessed the effect of long-term exposure of human T lymphocytes and dendritic cells (DCs) to moderate strength SMFs of different orientations focusing on the cytokine profile of activated T cells. Cultures of allogenic T lymphocytes and DCs (immature and matured by TLR3 and TLR7 agonists) were continuously exposed to four SMFs. The intensity of the applied field was 1 militesla (mT) or 56 mT of the upward- and downward-oriented pole of the SMF. Cell culture supernatants were assayed for IFN-γ, IL-4, IL-17, TNF-α, TNF-β, IL-1 β, IL-6, IL-8, and IL-10 by ELISA or flow cytometry. The upward-oriented 56 mT SMF significantly increased the release of IFN-γ and TNF-β (both p < 0.05) in the cell culture supernatants of T cells and immature DCs. In contrast, the same cultures exposed to the upward-oriented 1 mT SMF showed significantly elevated levels of IL-17 (p < 0.05). The levels of IL-4, TNF-α, IL-1 β, IL-6, IL-8, and IL-10 were not affected by the upward-oriented SMF. The downward-oriented 56 mT SMF increased TNF-α release when T cells were stimulated with mature DCs. The production of other cytokines was unchanged by the downward-oriented SMF. These findings demonstrate for the first time different in vitro biological effects of upward- and downward-oriented static magnetic fields on the cytokine production of T cells activated by DCs, helping to better understand SMF effects on the immune system and suggesting that the selective SMF effect on the immune response could have potential therapeutic effects in different immune-mediated disorders.

Background: Severe coagulation abnormalities are common in patients with COVID-19 infection. We aimed to investigate the relationship between pro-inflammatory cytokines and coagulation parameters concerning socio-demographic, clinical, and laboratory characteristics. Methods: Our study included patients hospitalized during the second wave of COVID-19 in the Republic of Serbia. We collected socio-demographic, clinical, and blood-sample data for all patients. Cytokine levels were measured using flow cytometry. Results: We analyzed data from 113 COVID-19 patients with an average age of 58.15 years, of whom 79 (69.9%) were male. Longer duration of COVID-19 symptoms before hospitalization (B = 69.672; p = 0.002) and use of meropenem (B = 1237.220; p = 0.014) were predictive of higher D-dimer values. Among cytokines, higher IL-5 values significantly predicted higher INR values (B = 0.152; p = 0.040) and longer prothrombin times (B = 0.412; p = 0.043), and higher IL-6 (B = 0.137; p = 0.003) predicted longer prothrombin times. Lower IL-17F concentrations at admission (B = 0.024; p = 0.050) were predictive of higher INR values, and lower IFN-γ values (B = −0.306; p = 0.017) were predictive of higher aPTT values. Conclusions: Our findings indicate a significant correlation between pro-inflammatory cytokines and coagulation-related parameters. Factors such as the patient’s level of education, gender, oxygen-therapy use, symptom duration before hospitalization, meropenem use, and serum concentrations of IL-5, IL-6, IL-17F, and IFN-γ were associated with worse coagulation-related parameters.

Background: Frequent episodes of nasal symptoms are the usual clinical manifestations (CM) of allergic rhinitis (AR) and have a significant negative impact on health-related quality of life (HRQoL) in adolescents. The purpose of this cross-sectional study was to test the hypothesis that cytokines in nasal mucus may be associated with HRQoL in adolescents with AR. Methods: European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L), “The Adolescent Rhinoconjunctivitis Quality of Life Questionnaire” (AdolRQLQ) and the Total 4 Symptom Score (T4SS) scoring system were administered to 113 adolescents with AR, nonallergic rhinitis (NAR) and to healthy control subjects. Nasal secretions were sampled and tested for 13 cytokines using a multiplex flow cytometric bead assay. Results: The AR group had significantly lower EQ-5D-3L (0.661 ± 0.267 vs. 0.943 ± 0.088; p < 0.001) and higher AdolRQLQ total scores (2.76 ± 1.01 vs. 1.02 ± 0.10; p < 0.001) compared to the control group. The AR group had higher concentrations of IL-1β (p = 0.002), IL-6 (p = 0.031), IL-8 (p < 0.001), IL17-A (p = 0.013) and IL-18 (p = 0.014) compared to the control group, and IL-1β, IL-6, IL17-A and IL-18 were significantly (p < 0.050) increased with disease progression. Cytokines IL-1β, IL-6, as well as severe CM, were identified as significant predictors of lower HRQoL in adolescents with AR. Conclusions: This study identified IL-1β, IL-6, as well as severe CM, as predictors of lower HRQoL in adolescents with AR. However, these results should only serve as a starting point for additional confirmation research.