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Rate of Torque Development Scaling Factor Decreased following a 6-Week Unilateral Isometric Training Using Electrostimulation or Voluntary Contractions
No full textThis study explored the changes in the rate of torque development scaling factor (RTD-SF) and maximum voluntary isometric contraction (MVC) variables following six weeks of unilateral isometric electromyostimulation (EMS) and voluntary (VOL) exercises. Twenty-six physically active participants were randomly assigned to EMS (n = 13) or a VOL group. MVC and RTD-SF of the quadriceps femoris of both legs were assessed before and after training. EMS and VOL exercises had identical frequency (three sessions/week), intensity (60% MVC), volume (40 contractions), and work-to-rest ratio (18 min: 6.25 s of work/20 s of rest). There were no between-group differences for the trained leg with overall increases in maximal torque (Tmax) of ~29% (d = 2.11–2.12), ~13% for RTDmax (d = 0.92–1.10); ~23% for Intercept (d = 0.72–0.78), and reduction in RTD-SF by ~15% (d = 1.01–1.10). In the non-trained leg, significant moderate change was only observed after EMS for RTD-SF which decreased by 12.5% (d = 0.76). Both EMS and VOL training applied at equivalent workloads positively impact on Tmax, RTDmax, and Intercept, but they negatively affect the quickness with which muscle contracts across a wide range of submaximal forces. Using a moderate training intensity in regularly physically active participants could explain the absence of cross-education in the VOL group
Ispitivanje citotoksičnog potencijala gljiva za medicinsku upotrebu in vitro u ljudskih staničnih linija raka dojke
No full textMedicinal mushroom extracts, i.e. their dried biomass, have long been known as sources of bioactive compounds with positive effects on
the human health. The antioxidant, antigenotoxic, antiviral, and immunomodulatory properties of the commercially available extracts
Agaricus blazei auct. non Murrill (AB), Cordyceps sinensis (Berk.) Sacc. (CS), and Immune Assist (IA) have already been documented. This
study, studied the influence of these three mushrooms on the viability of cell lines MCF-7, MDA-MB-231, and HS-5. The cytotoxicity
of AB, CS, and IA at different concentrations (25, 50, 100, 200, 400 and 800 μg/mL) was evaluated using the MTT assay. The results
showed that AB was the most effective and induced cytotoxicity in both cancer cell lines, with IC50 values of 96.7 μg/mL for MCF-7 and
368.4 μg/mL for MDA-MB-231. After treatment with CS and IA, the half-maximal inhibitory concentration was reached only in MDAMB-231 cells (IC50=613 μg/mL for CS and 343.3 μg/mL for IA). We have shown here that AB, CS and IA can suppress the growth of
MCF-7 and MDA-MB-231 cell lines, while affecting the survival of healthy HS-5 cells to a much lesser extent. Our in vitro results suggested
that AB, CS and IA are promising natural sources with potential anticancer activity.Ekstrakti gljiva za medicinsku upotrebu, odnosno njihova osušena biomasa, odavno su poznati kao izvori bioaktivnih spojeva s pozitivnim učinkom na ljudsko zdravlje. Antioksidacijska, antigenotoksična, antivirusna i imunomodulirajuća svojstva komercijalno dostupnih ekstrakata Agaricus blazei auct. non Murrill (AB), Cordyceps sinensis (Berk.) Sacc. (CS) i Immune Assist (IA) već su dugo poznata. Ovim istraživanjem ispitan je učinak tih triju gljiva na održivost staničnih linija MCF-7, MDA-MB-231 i HS-5. Citotoksičnost AB, CS i IA u različitim koncentracijama (25, 50, 100, 200, 400 i 800 μg/mL) procijenjena je MTT testom. Rezultati su pokazali da je AB izazvao najučinkovitiju citotoksičnost u objema staničnim linijama raka, s IC50 vrijednostima od 96,7 μg/mL za MCF-7 i 368,4 μg/mL za MDA-MB-231. Nakon tretmana s CS i IA polumaksimalna inhibitorna koncentracija postignuta je samo u stanicama MDA-MB-231 (IC50=613 μg/mL za CS i 343,3 μg/mL za IA). Ovo je istraživanje pokazalo da AB, CS i IA mogu donekle suzbiti rast staničnih linija raka bez utjecaja na preživljavanje normalnih HS-5 stanica. Naši rezultati sugeriraju da su AB, CS i IA obećavajući prirodni izvori s potencijalnim djelovanjem protiv raka
Gamma-Band Auditory Steady-State Response and Attention: A Systemic Review
No full textAuditory steady-state response (ASSR) is the result of the brain’s ability to follow and entrain its oscillatory activity to the phase and frequency of periodic auditory stimulation. Gamma-band ASSR has been increasingly investigated with intentions to apply it in neuropsychiatric disorders diagnosis as well as in brain–computer interface technologies. However, it is still debatable whether attention can influence ASSR, as the results of the attention effects of ASSR are equivocal. In our study, we aimed to systemically review all known articles related to the attentional modulation of gamma-band ASSRs. The initial literature search resulted in 1283 papers. After the removal of duplicates and ineligible articles, 49 original studies were included in the final analysis. Most analyzed studies demonstrated ASSR modulation with differing attention levels; however, studies providing mixed or non-significant results were also identified. The high versatility of methodological approaches including the utilized stimulus type and ASSR recording modality, as well as tasks employed to modulate attention, were detected and emphasized as the main causality of result inconsistencies across studies. Also, the impact of training, inter-individual variability, and time of focus was addressed
Dietary Omega-3 PUFA Intake in Patients with Chronic Kidney Disease: The Association with Vitamin D Deficiency, Intima–Media Thickness and Blood Pressure
No full textBackground/Objectives: Numerous risk factors associated with development of cardiovascular disease (CVD) have been unfavorably altered in patients with chronic kidney disease (CKD). Low omega-3 polyunsaturated fatty acid (PUFA) intake and vitamin D deficiency are potential cardiometabolic risk factors in patients with CKD. The aim of this study was to evaluate dietary intake and status of omega-3 PUFA and vitamin D in pre-dialysis and hemodialysis patients and to examine the association of dietary α-linolenic acid (ALA) and fish consumption with blood pressure and carotid intima–media thickness (C-IMT), representing a non-invasive marker of atherosclerosis in CKD patients. Methods: All 77 selected patients (36 pre-dialysis, 41 on hemodialysis) underwent standardized clinical, nutritional, and laboratory assessments. Repeated 24 h recalls were performed to assess dietary intake. The fatty acid profile was determined by gas–liquid chromatography. Results: Inadequate vitamin D intake and vitamin D status were found in 95% of patients. PUFA profiles did not differ between hemodialysis and pre-dialysis participants. Dietary intake of ALA was negatively correlated with systolic blood pressure (SBP) (p = 0.013), C-IMT (p = 0.002), serum CRP (p = 0.044), iPTH (p = 0.01), and 25(OH)D3 (p = 0.006). ALA intake of more than 0.23 g daily was linked with lower SBP (p = 0.001), serum 25(OH)D3 (p = 0.004), and C-IMT (p = 0.002). Conclusions: This study contributes to a better understanding of the relationship between dietary ALA intake and C-IMT in CKD. The results of this study could emphasize the significant role of the high prevalence of vitamin D deficiency and inadequate omega-3 PUFA intake and status regarding CVD health in CKD patients
Comparative Analysis of Fatty Acid Profiles in Erythrocyte Membranes in Vegetarians Compared to Omnivores
No full textBackground: The fatty acid profiles in cellular membranes can be influenced by many endogenic and external factors, including diet. They are also associated with numerous metabolic and health conditions, including cardiovascular diseases and inflammation. Objective: This study provides a comparative analysis of the fatty acid profiles in subjects on vegetarian and omnivorous diets. Methods: The study enrolled 152 apparently healthy subjects, comprising 78 omnivores and 74 individuals who had followed a vegetarian diet for a minimum of 2 years, including 61 vegans and 13 lacto-ovo vegetarians. The subjects in the omnivore and vegetarian groups were matched by gender, age, and body mass index (BMI). The composition of the fatty acids in their erythrocyte membranes was determined using gas–liquid chromatography and presented as a percentage of total fatty acids. Results: The study revealed statistically significant differences in the fatty acid profiles: vegetarians had higher levels of oleic acid (OA, 18:1 n-9) (p < 0.001) and linoleic acid (LA, 18:2 n-6) (p < 0.001), while at the same time having lower levels of gamma-linolenic acid (GLA, 18:3 n-6) (p < 0.05), eicosapentaenoic acid (EPA, 22:5 n-3) (p < 0.001), docosapentaenoic acid (DPA, 22:5 n-3) (p < 0.001), docosahexaenoic acid (DHA, 22:6 n-3) (p < 0.001), and total omega-3 polyunsaturated fatty acid (PUFA) (p < 0.001) and a lower omega-3 index (p < 0.001). Additionally, they had lower omega-3 to omega-6 PUFA (p < 0.001); EPA/arachidonic acid (ARA, 20:4 n-6) (p < 0.001); and DHA/ARA ratios (p < 0.001). The activity of delta-6 desaturases (D6D), estimated as the GLA/LA ratio, was higher in the omnivores (p < 0.005), while the activity of elongase 2 (ELOV2), estimated as the DPA/EPA ratio, was higher in the vegetarians (p < 0.005). Most of the differences presented in both vegans and vegetarians, except for GLA and D6D, where differences were observed only in vegans compared to omnivores. Discussion: This study highlights the distinct fatty acid profiles associated with vegan, lacto-ovo vegetarian, and omnivorous diets, suggesting their differential impact on inflammation, disease protection, and overall health. Understanding the implications of the fatty acid profiles within these dietary patterns can be used for personalized nutritional recommendations and supplementation for individuals adhering to specific dietary lifestyles.Proceedings of the 14th European Nutrition Conference FENS 2023, Belgrade, Serbia, 14–17 November 2023
Effect of ferulic acid, hyperoside, and rutin on reactivity of human serum albumin Cys-34 thiol group
No full textHuman serum albumin (HSA) has seven fatty acid (FA) binding sites across its three domains, which
overlap with its main ligand binding sites.1,2 FA binding can affect the reactivity of HSA’s Cys-34
thiol group, influencing its antioxidant properties.2 This study investigated how selected polyphenols
affect the reactivity of HSA with bound stearic acid (S) in molar ratios S/HSA of 1:1 and 4:1. The
binding of S increased the Cys-34 thiol group reactivity from 14.11×10⁻³ s⁻¹ for defatted HSA to
17.49×10⁻³ s⁻¹ (23.95%) for S/HSA 1:1 and 29.27×10⁻³ s⁻¹ (107.41%) for S/HSA 4:1. Polyphenols
ferulic acid (F), hyperoside (H), and rutin (R) altered k’ values differently: increasing them in S/HSA
1:1 complexes (F for 6.3%; H for 16.18%; R for 8.82%) and decreasing them in 4:1 complexes (F
for 6.94%; H for 17.81%; R for 17.13%). According to the results obtained, selected polyphenols,
binding to subdomain IIA, influence Cys-34 thiol reactivity in HSA/S complexes, exhibiting both
cooperative and competitive effects depending on the S/HSA ratio
Impact of UV radiation and temperature on the spongy moth and the brown-tail moth in Serbia
Get PDFThe impact of climate change on insect pests is an emerging topic in forestry and forest science. This study investigates the relationships between two broadleaved forest pests – spongy moth (Lymantria dispar L.) and brown-tail moth (Euproctis chrysorrhoea L.) – and oaks (Quercus sp.) as their hosts. Oak forests cover almost one-third of the total forest area of Serbia and are ecologicallyvery valuable, but at the same time vulnerable, as being affected in adverse ways by several primary pests and pathogens. Since 1862, Serbia experienced several extremely large outbreaks of spongy moth with more than a hundred thousand hectares completely defoliated each time, while brown-tail moth occurred periodically with a much lower spatial extent. The aim of this research was to investigate the effect of UV radiation (UVR) and air temperature on spongy moth and brown-tail moth in Serbian forests. We used simulations of the coupled regional climate model EBU-POM (Eta Belgrade University-PrincetonOcean Model) for the A1B scenario for the period 2001-2030 as main input and different statistical methods to explore relationships between observations of pest spread and climate change impacts. Our results suggest: (i) increasing the areas affected by spongy moth due to its sensitivity on UVR in May, and (ii) altitudinal spreading of brown-tail moth population up to 800 – 1000 m. This research indicates that in situ forest observations in Serbia are not only affected by climate change, but also by the combined effect of climate on forest pests. For further research, we recommend exploring other forest stressors or dieback phenomena in European forests by applying the same or similar regional climate model dataset
Country-Level Modeling of Forest Fires in Austria and the Czech Republic: Insights from Open-Source Data
Get PDFForest fires are becoming a serious concern in Central European countries such as Austria (AT) and the Czech Republic (CZ). Mapping fire ignition probabilities across countries can be a useful tool for fire risk mitigation. This study was conducted to: (i) evaluate the contribution of the variables obtained from open-source datasets (i.e., MODIS, OpenStreetMap, and WorldClim) for modeling fire ignition probability at the country level; and (ii) investigate how well the Random Forest (RF) method performs from one country to another. The importance of the predictors was evaluated using the Gini impurity method, and RF was evaluated using the ROC-AUC and confusion matrix. The most important variables were the topographic wetness index in the AT model and slope in the CZ model. The AUC values in the validation sets were 0.848 (AT model) and 0.717 (CZ model). When the respective models were applied to the entire dataset, they achieved 82.5% (AT model) and 66.4% (CZ model) accuracy. Cross-comparison revealed that the CZ model may be successfully applied to the AT dataset (AUC = 0.808, Acc = 82.5%), while the AT model showed poor explanatory power when applied to the CZ dataset (AUC = 0.582, Acc = 13.6%). Our study provides insights into the effect of the accuracy and completeness of open-source data on the reliability of national-level forest fire probability assessment
Associations of fatty acids composition and estimated desaturase activities in erythrocyte phospholipids with biochemical and clinical indicators of cardiometabolic risk in non-diabetic Serbian women: the role of level of adiposity
Get PDFIntroduction: Fatty acids (FAs) composition and desaturase activities can be altered in different metabolic conditions, but the adiposity-independent associations with clinical and biochemical indicators of cardiometabolic risk are still unclear. This study aimed to analyze the associations of FAs composition and estimated desaturase activities with anthropometric, clinical, and biochemical cardiometabolic risk indicators in non-diabetic Serbian women, and to investigate if these associations were independent of the level of adiposity and other confounders.
Methods: In 76 non-diabetic, otherwise healthy Serbian women, aged 24-68 years, with or without metabolic syndrome or obesity (BMI=23.6±5.6 kg/m2), FA composition in erythrocyte phospholipids was measured by gas-liquid chromatography. Desaturase activities were estimated from product/precursor FAs ratios (D9D:16:1n-7/16:0; D6D:20:3n-6/18:2n-6; D5D:20:4n-6/20:3n-6). Correlations were made with anthropometric, biochemical (serum glucose, triacylglycerols, LDL-C, HDL-C, ALT, AST, and their ratios) and clinical (blood pressure) indicators of cardiometabolic risk. Linear regression models were performed to test the independence of these associations.
Results: Estimated desaturase activities and certain FAs were associated with anthropometric, clinical and biochemical indicators of cardiometabolic risk: D9D, D6D, 16:1n-7 and 20:3n-6 were directly associated, while D5D and 18:0 were inversely associated. However, the associations with clinical and biochemical indicators were not independent of the associations with the level of adiposity, since they were lost after controlling for anthropometric indices. After controlling for multiple confounders (age, postmenopausal status, education, smoking, physical activity, dietary macronutrient intakes, use of supplements, alcohol consumption), the level of adiposity was the most significant predictor of desaturase activities and aforementioned FAs levels, and mediated their association with biochemical/clinical indicators. Vice versa, desaturase activities predicted the level of adiposity, but not other components of cardiometabolic risk (if the level of adiposity was accounted). While the associations of anthropometric indices with 16:1n-7, 20:3n-6, 18:0 and D9D and D6D activities were linear, the associations with D5D activity were the inverse U-shaped. The only adiposity-independent association of FAs profiles with the indicators of cardiometabolic risk was a positive association of 20:5n-3 with ALT/AST ratio, which requires further exploration.
Discussion: Additional studies are needed to explore the mechanisms of the observed associations