Ectosomes as immunomodulators

Considerable progress has been made in recognizing microvesicles as important mediators of intercellular communication rather than irrelevant cell debris. Microvesicles released by budding directly from the cell membrane surface (i.e., ectocytosis) either spontaneously or in response to various stimuli are called shed vesicles or ectosomes. Ectosomes are rightside-out vesicles with cytosolic content, and they expose phosphatidylserine in the outer leaflet of their membrane. Depending on their cellular origin, ectosomes have been associated with a broad spectrum of biological activities. In the light of recent findings, we now know that ectosomes derived from polymorphonuclear leukocytes, erythrocytes, platelets, and tumor cells have profound effects on the innate immune system, as well as on the induction of the adaptive immunity, globally reprogramming cells such as macrophages or dendritic cells toward an immunosuppressive and possibly tolerogenic phenotype. Although the effects observed in the circulation are mainly procoagulant and pro-inflammatory, ectosomes might be anti-inflammatory/immunosuppressive in local inflammatio

The effect of time of day on Special Judo Fitness Test in active judokas: Evaluation in terms of chronotype

© 2023 The Author(s). Published with license by Taylor & Francis Group, LLC. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/The present cross-sectional study aims to examine the effect of time of day on the judo-specific performance in judokas, considering their chronotypes. Twenty-four male judokas participated in the study where the Morningness-Eveningness Questionnaire was administered, and on it, they were divided into morning-type (MT:12-judokas) and evening-type groups (ET:12-judokas). Afterwards, the Special Judo Fitness Test (SJFT) was applied to both groups at three different times (morning: 09:00 h, afternoon: 13:00 h and evening: 17:00 h) with body temperature measured before and after every SJFT performance. As a result, the Group*Test Time interaction significantly affected overall throwing performance during SJFT [F(2,44) = 29.437, p = 0.001, η2p: .572]. Furthermore, a significant time effect was found for the SJFT index [F(2,44) = 5.118, p = 0.010, η2p: .189] and for the Group*Test Time interaction with the mean value of the index [F(2,44) = 24.424, p < 0.001, η2p: .526]. Furthermore, body temperature had a significant time effect [F(2,44) = 301.454, p < 0.001, η2p: .932] and the Group*Test Time interaction [F(2,44) = 5.802, p = 0.006, η2p: .209]. In conclusion, coaches and exercise experts should consider judo athletes’ chronotype when planning special training programs to improve judo-specific anaerobic capacity. Furthermore, to minimize the impact of time of day and chronotype on athletes’ performance in competitions, it is recommended that MT athletes develop their judo-specific anaerobic capacity in the evening hours, when their performance is lower, while ET athletes should do so in the morning hours when their performance is lower via randori training.Peer reviewe

The Risk Factors Associated with Grip Lock Injuries in Artistic Gymnasts: A Systematic Review

Artistic gymnastics (AG) is a sport that demands grace, strength, and flexibility, leading to a broad spectrum of injuries. The dowel grip (DG) is widely used by gymnasts to securely hold onto the high bar or uneven bars. However, incorrect usage of the DG can result in grip lock (GL) injuries. This systematic review aims to (1) identify studies that have investigated the risk factors related to GL injuries among gymnasts and (2) synthesize the key evidence. A comprehensive electronic search was conducted in the following databases: PubMed, ScienceDirect, Elsevier, SportDiscus, and Google Scholar, covering the period from their inception until November 2022. The data extraction and analysis were independently completed by two investigators. A total of 90 relevant studies were initially identified, out of which seven clinical trials met the eligibility criteria. For the quantitative synthesis, five studies were included. The details extracted from each article include: the sample characteristics (number, gender, age, and health status), the study design, the instrumentation or intervention used, and the final results. Our results revealed that the underlying causes of the risk factors of GL injuries were the irregular checking of the dowel grip and the mating surface of the bar, the tearing of the dowel of the leather strap, and the use of the dowel grip in different competition apparatuses. In addition, GL injuries may occur either as severe forearm fractures or mild injuries. Excessive flexion of the forearm and overpronation of the wrist during rotational movements, such as the swing or backward/forward giant circle, may increase the possibility of GL injury on the high bar. Future studies should focus on GL injury prevention strategy and rehabilitation protocol for GL injuries. Further high-quality research is required to establish the validity of these findings. © 2023 by the authors.European Commission, EC: .02.2.69/0.0/0.0/18_054/0014627Published with the financial support of the European Union, as part of the project entitled Development of capacities and environment for boosting the international, intersectoral, and interdisciplinary cooperation At UWB, project reg. no.CZ.02.2.69/0.0/0.0/18_054/0014627

Athletic performance, sports experience, and exercise addiction: an association study on ANKK1 gene polymorphism rs1800497

IntroductionExercise addiction is a phenomenon being able to affecting the athletic performance. The gene, ANKK1 and the polymorphism NM_178510.2:c.2137G &gt; A (rs1800497) has been linked to the exercise addiction. However, further studies on diverse populations and sport branches are needed to totally explore the possible association of this polymorphism with the athletic performance. Thus, the present study aims to decipher any possible relations of the rs1800497 polymorphism with the athletic performance/personal best (PB) and sport experience of elite athletes.MethodsSixty volunteer elite athletes (31 sprint/power and 29 endurance) and 20 control/sedentary participated in the study. The polymorphism was genotyped using whole exome sequencing approach and PB were determined according to the International Association of Athletics Federations (IAAF) score.ResultsOur results underlined that there were not any significance differences for both allele and genotype frequencies between the groups in terms of athletic performance, although the frequency of allele G was higher (p &gt; 0.05). Nevertheless, sport experience significantly associated with the rs1800496 polymorphism (p &lt; 0.05).DiscussionIn conclusion, genotype G/G could be inferred to be linked to the higher sport experience and athletic performance. Still, further studies with higher number of participants are needed to conclude the association of this polymorphism with athletic parameters

Association of Heart Rate Variability With Silent Brain Infarcts in Patients With Atrial Fibrillation

Purpose: Silent brain infarcts (SBI) are frequently detected in patients with atrial fibrillation (AF), but it is unknown whether SBI are linked to autonomic dysfunction. We aimed to explore the association of autonomic dysfunction with SBI in AF patients. Methods: 1,358 AF patients without prior stroke or TIA underwent brain MRI and 5-min resting ECG. We divided our cohort into AF patients who presented in sinus rhythm (SR-group, n = 816) or AF (AF-group, n = 542). HRV triangular index (HRVI), standard deviation of normal-to-normal intervals, mean heart rate, root mean square root of successive differences of normal-to-normal intervals, 5-min total power and power in the low frequency, high frequency and very low frequency range were calculated. Primary outcome was presence of SBI in the SR group, defined as large non-cortical or cortical infarcts. Secondary outcomes were SBI volumes and topography. Results: Mean age was 72 ± 9 years, 27% were female. SBI were detected in 10.5% of the SR group and in 19.9% of the AF group (p < 0.001). HRVI <15 was the only HRV parameter associated with the presence of SBI after adjustment for clinical covariates in the SR group [odds ratio (OR) 1.67; 95% confidence interval (CI): 1.03–2.70; p = 0.037]. HRVI <15 was associated with larger brain infarct volumes [β (95% CI) −0.47 (−0.84; −0.09), p = 0.016] in the SR group and was more frequently observed in patients with right- than left-hemispheric SBI (p = 0.017). Conclusion: Impaired HRVI is associated with SBI in AF patients. AF patients with autonomic dysfunction might undergo systematic brain MRI screening to initiate intensified medical treatment

Silent brain infarcts impact on cognitive function in atrial fibrillation

Aims: We aimed to investigate the association of clinically overt and silent brain lesions with cognitive function in atrial fibrillation (AF) patients. Methods and results: We enrolled 1227 AF patients in a prospective, multicentre cohort study (Swiss-AF). Patients underwent standardized brain magnetic resonance imaging (MRI) at baseline and after 2 years. We quantified new small non-cortical infarcts (SNCIs) and large non-cortical or cortical infarcts (LNCCIs), white matter lesions (WML), and microbleeds (Mb). Clinically, silent infarcts were defined as new SNCI/LNCCI on follow-up MRI in patients without a clinical stroke or transient ischaemic attack (TIA) during follow-up. Cognition was assessed using validated tests. The mean age was 71 years, 26.1% were females, and 89.9% were anticoagulated. Twenty-eight patients (2.3%) experienced a stroke/TIA during 2 years of follow-up. Of the 68 (5.5%) patients with ≥1 SNCI/LNCCI, 60 (88.2%) were anticoagulated at baseline and 58 (85.3%) had a silent infarct. Patients with brain infarcts had a larger decline in cognition [median (interquartile range)] changes in Cognitive Construct score [-0.12 (-0.22; -0.07)] than patients without new brain infarcts [0.07 (-0.09; 0.25)]. New WML or Mb were not associated with cognitive decline. Conclusion: In a contemporary cohort of AF patients, 5.5% had a new brain infarct on MRI after 2 years. The majority of these infarcts was clinically silent and occurred in anticoagulated patients. Clinically, overt and silent brain infarcts had a similar impact on cognitive decline. Clinical trial registration: ClinicalTrials.gov Identifier: NCT02105844, https://clinicaltrials.gov/ct2/show/NCT02105844. Keywords: Atrial fibrillation; Brain infarction; Cognitive function; Magnetic resonance imaging; Oral anticoagulation

Utjecaj desflurana i sevoflurana na razine oksidativnog stresa u tkivima štakora

General anaesthetics are often used in patients who are under oxidative stress due to a critical illness or surgical trauma. Some anaesthetics may worsen oxidative stress and some may act as antioxidants. The aim of this study was to evaluate liver, brain, kidney, and lung tissue oxidative stress in rats exposed to desflurane and sevoflurane and in unexposed rats. The animals were divided in three groups: control (received only air); sevoflurane (8 %), and desflurane (4 %). After four hours of exposure, we evaluated the levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), Cu, and Zn. Exposure to either of the anaesthetics significantly increased lung MDA levels compared to control (Mann-Whitney U test; P<0.05), probably because it is the tissue directly exposed to anaesthetic gases. Oxidative stress and antioxidant activity in other tissues varied between the desflurane and sevoflurane groups. Our results suggest that anaesthesiologist should not only be aware of the oxidative or antioxidative potential of anaesthetics they use, but should also base their choices on organs which are the most affected by their oxidative actionkisikovih radikala tako i zbog smanjene aktivnosti obrambenih sustava koji se mogu oduprijeti njihovu djelovanju. Stoga su saznanja o antioksidativnom kapacitetu anestetika koji se primjenjuju prije nekoga kirurškog zahvata vrlo važna i od velikog su kliničkog značenja. Sevofl uran i desfl uran su inhalacijski anestetici koji se učestalo rabe u svrhu uvođenja bolesnika u anesteziju. Cilj ovog istraživanja bio je utvrditi razine oksidativnog stresa u različitim tkivima štakora i usporediti razlike u odgovoru tkiva na izlaganje navedenim anesteticima. U tu svrhu razine oksidativnog stresa izmjerili smo u jetri, mozgu, bubrezima i plućima štakora podijeljenih u tri eksperimentalne skupine. Kontrolna skupina udisala je samo zrak, dok su druge dvije skupine izložene 8 %-tnomu sevofl uranu te 4 %-tnomu desfl uranu tijekom 4 h. Nakon završetka obrade životinje su žrtvovane i uzimani su im uzorci tkiva za biokemijske analize. Mjerena je razina malondialdehida (MDA), aktivnst enzima superoksid dismutaze (SOD) i glutation peroksidaze (GSH-Px) te razine bakra i cinka. Izloženost anesteticima izazvala je oksidativni stres u plućima, na što upućuje značajno povišena razina MDA (Mann-Whitney U-test P<0.05) izmjerena u plućnom tkivu štakora obiju izloženih skupina u odnosu na kontrolu. Plućno je tkivo u odnosu na ostala tkiva podložnije štetnim utjecajima reaktivnih kisikovih radikala vjerojatno stoga što je ono prvo izloženo plinovitim anesteticima nakon njihova ulaska u organizam. Razine oksidativnog stresa i antioksidativne aktivnosti koje smo izmjerili u ostalim tkivima bile su različite te su ovisile o primijenjenom anestetiku. Na osnovi dobivenih rezultata možemo zaključiti da bi se zbog različitog odgovora tkiva izbor anestetika trebao provoditi na individualnoj osnovi

Immunomodulation by ectosomes

Considerable progress has been made in recognizing microvesicles as important mediators of intercellular communication rather than irrelevant cell debris. Microvesicles released by budding directly from the cell membrane surface either spontaneously or in response to various stimuli are called ectosomes. Of particular interest is that ectosomes released by polymorphonuclear neutrophils (PMN-Ect) down regulate the inflammatory potential of macrophages. This finding was a real surprise since PMNs are known to be proinflammatory cells par excellence. Thus the very same cells known for their destruction capacity have the property of releasing ectosomes, which inhibit further macrophage activation, although various cytokines released by PMNs are chemotactic for macrophages. This might be a powerful regulatory mechanism responsible for the control of excess inflammation. In my thesis I wanted to (1) see whether the same ectosomes have also the property to down regulate dendritic cells (DCs), so as to prevent the activation of the acquired immune system (T cells), when it is not required (section 1). (2) see whether ectosomes from other cells would have similar properties. For this we investigated ectosomes released by erythrocytes (section 2). (3) define the signaling pathways induced by ectosomes (section 3). (1) PMN-Ect were recently shown to induce an anti-inflammatory response on human monocyte-derived macrophages (HMDMs). I found that PMN�Ect also inhibited the LPS-induced maturation of human monocyte-derived DCs (MoDCs). This effect was evidenced by reduced expression of cell surface markers (CD40, CD80, CD83, CD86 and HLA�DP DQ DR), inhibition of cytokine release (IL�8, IL�10, IL�12, and TNFα), and new morphological and functional characteristics (reduced phagocytic activity, and increased TGF-β1 release). Importantly, the skewed MoDC differentiation resulted in a reduced capacity to activate T-cells, suggesting an active role for PMN-Ect in adaptive immunity as well. (2) Microvesicles derived from erythrocytes during storage had all the properties of ectosomes. E-ecto revealed an inhibitory potential on zymosan A and LPS activated HMDMs as shown by down-regulation of IL-8 and TNFα release. However, different from PMN-Ect, E-ecto did not enhance the release of TGF�β1. In addition, the effect of E�ecto was found to be long lasting. Thus, E-ecto transfused with erythrocytes may account for some of the immunosuppressive effects seen after blood transfusions (3) The receptors and signaling pathways involved in ectosome-induced down-modulation are unknown. I showed that the encounter of PMN-Ect with HMDMs induced an immediate calcium flux. Mer receptor as well as the phosphatidylinositol 3�kinase (PI3K)/Akt pathway were activated, and NFκB translocation and phosphorylation were blocked. Consequently, the transcription of many proinflammatory genes in zymosan A activated HMDMs were reduced. Finally, my data revealed that TGF-β1 release induced by PMN-Ect was not related to a modification in its transcription. Taken together these results suggest that ectosomes have a profound effect on the innate immune system, here macrophages, as well as on the induction of the adaptive immune system, here DCs, globally reprogramming these cells toward an immunosuppressive and possibly tolerogenic phenotype

Ectosomes as immunomodulators

Considerable progress has been made in recognizing microvesicles as important mediators of intercellular communication rather than irrelevant cell debris. Microvesicles released by budding directly from the cell membrane surface (i.e., ectocytosis) either spontaneously or in response to various stimuli are called shed vesicles or ectosomes. Ectosomes are rightside-out vesicles with cytosolic content, and they expose phosphatidylserine in the outer leaflet of their membrane. Depending on their cellular origin, ectosomes have been associated with a broad spectrum of biological activities. In the light of recent findings, we now know that ectosomes derived from polymorphonuclear leukocytes, erythrocytes, platelets, and tumor cells have profound effects on the innate immune system, as well as on the induction of the adaptive immunity, globally reprogramming cells such as macrophages or dendritic cells toward an immunosuppressive and possibly tolerogenic phenotype. Although the effects observed in the circulation are mainly procoagulant and pro-inflammatory, ectosomes might be anti-inflammatory/immunosuppressive in local inflammation

Examining the Influence of Self-Esteem and Digital Literacy on Professional Competence Factors in Dental Education: A Cross-Sectional Study

This study aims to investigate the effects of digital literacy and self-esteem on dental students’ perceptions of professional competence and to provide recommendations for improving educational programs in dental schools. A mixed-methods, descriptive, and relational scanning design was employed, using a questionnaire comprising demographic information, the Rosenberg Self-Esteem Scale (RSES), the Digital Literacy Scale (DLS), and the Professional Competence Scale (PCS). The sample included 427 dental students in Istanbul, Turkey. Statistical analyses included Cronbach Alpha, Confirmatory Factor Analysis, Mann–Whitney U, Kruskal–Wallis, Spearman’s rho correlation, and the Generalized Linear Model (Logit Model). The majority of participants were female (65.6%), aged 21 or older (85.2%), and in their 4th grade of study (35.2%). There were no significant differences in PCS scores concerning gender, age, grade, type of residence, and residence location (p > 0.05). However, PCS scores were significantly higher among those who listed dentistry among their top five preferences, expressed high satisfaction with education, and demonstrated high professional interest (p p p p p p p p p p < 0.01) significantly influenced PCS. The findings underscore self-esteem and digital literacy’s integral role in shaping dental students’ perceptions of their professional abilities. Digital literacy is a substantial pillar supporting students’ professional competency. Coupled with a genuine interest in the field and bolstered self-confidence, digital literacy proves instrumental in enhancing students’ academic success in dentistry. By emphasizing and expanding upon digital literacy content within the curriculum, universities can further propel advancements in the dental domain. As such, it is pivotal for dental institutions to weave strategies into their educational fabric to elevate students’ self-esteem and digital proficiency