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Reactive oxygen species (ROS) production is known to increase as a result of muscular contractile activity and this phenomenon may perturb the fine-controlled cellular redox homeostasis within cells and tissues. We studied the possible correlations between individual aerobic performance-related factors and the oxidative stress markers profile in the serum of thirty-five endurance male runners that experienced a modified Bruce-based maximal graded exercise test. Our investigation assessed the systemic levels of malondialdehyde (MDA), protein carbonyl content (PCC) and total antioxidant status (TAS). We found that redox-related parameters and aerobic performance indicators were correlated. Indeed, significant negative associations between TAS and PCC (r-value -0.7, p<0.001) and between TAS and total protein content (r-value -0.4, p=0.005) were observed. A significant positive association between total protein and PCC (r-value 0.4, p=0.012) was also revealed. Only a trend of negative correlation between serum total protein and anaerobic threshold (r-value -0.3, p=0.07) was found. Interestingly, different responses in MDA levels were elicited by the ergometric test as a function of the individual anaerobic threshold. High aerobic capacities may be promising anthropometric factors indicative of adapted biochemical environments featuring enhanced protection against the oxidative challenge elicited by both regular endurance training and single intense exercise bouts.

ABSTRACT. An ultrastructural and functional study was performed during methotrexate (MTX) induced apoptosis on HL-60leukemia cells. The fine preservation of plasma membranearchitecture and organellar components was present untill latest apoptotic stages, despite strong nuclear changes. This observation suggests the presence of a residual cell metabolic activity, which is here investigated. DNAagarose gel electrophoresis demonstrated its fragmentation, which was also confirmed in situ by nick translation con focal analysis. Nuclear purification was subsequently performed to investigate DNApolymerase activities. DNApolymerase a activity appeared strongly reduced from the early phases of methotrexate treatment, while the rate of DNApolymerase fi synthesis was found to increase progressively along with the time of drug treatment. Low levels of DNApolymerase y activity were revealed both in control and in treated cells, suggesting the irrelevant involvement of this enzyme in the DNAmetabolism of this model. DNApolymerase fi appears thus to be the enzyme preminently correlated to cell attempts to repair the methotrexate-induced DNAdamage.Programmed cell death is an active process of genetically controlled cell deletion, which plays an essential role in a number of biological events (10, 15, 26,37,39). It represents, a powerful mean for modulating tissue growth during embryonic development and tissue turnover in adult life (7, 19, 21, 24). It is also the most frequent mechanismwhich reduces tumor mass after chemotherapy (3, 22, 23, 28, 31).Cells undergoing programmed cell death present somepeculiar morphological features , generally defined "apoptosis, " which have been widely described and appear comparable in different cells, even in presence of strongly different triggering conditions (12).With the cell nucleus as the first target, chromatin undergoes a progressive margination and clustering with the successive formation of cup-shaped compact zones at a nuclear pole, sharply separated from the diffuse chromatin domains (13). In addition, nuclear pores cluster in particular areas of the nuclear envelope, adjacent to the diffuse chromatin (12). Dense micronuclei finally appear in the perinuclear cysternae, or, more frequently, scattered throughout the cytoplasm (35).Despite this strong nuclear rearrangement, the apoptotic cells surprisingly present a good preservation of the plasma membraneand organellar component. These observations suggest the persistence of a residual cell metabolic activity. A correlation between chromatin structure and its activity is now in progress by means of a morphometrical study on apoptotic freeze-fractured cells (33-34), but little is known about the enzymatic activities.

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The response of T-cells to peptide antigen plus major histocompatibility complex (MHC) consists of a series of cellular events collectively called T-cell activation. An essential component of this pathway is phospholipase C (PLC)gamma1, whose hydrolytic activity increases rapidly after binding of ligands to the T-cell receptor (TCR) and consequent activation of tyrosine kinases. Recent studies also suggest a GTP binding protein-dependent activation of PLCbeta during the early steps of T-cell activation. On the basis of these findings, we first checked the expression of PLC isoforms by Western blotting and by confocal and electron microscopy techniques, and then we looked for the phosphoinositide breakdown induced by CD3 engagement in cord and adult T-lymphocytes. Our results indicated that PLCbeta1 was almost exclusively expressed in cord T-cells, whereas PLCbeta2 was more strongly represented in the adult. The amount of PLCgamma1 was found to be larger in the adult than in cord cells. No significant differences were found in PLCgamma2 and delta2 expression. PLCdelta1 was scarcely detectable. On CD3 stimulation, adult lymphocytes gave rise, as expected, to a dramatic increase in phosphoinositide breakdown, whereas in cord cells this response was scarcely detected. These results indicate that a shift in PLC expression occurs in the postnatal period and that this change is associated with induction of the capability to respond to CD3 engagement with phosphoinositide hydrolysis.

DNA replicative and repair machinery was investigated by means of different techniques, including in vitro nuclear enzymatic assays, immunoelectron microscopy and confocal microscopy, in apoptotic cell lines such as HL-60 treated with methotrexate, P815 and K562 exposed to low temperatures and Friend cells exposed to ionizing radiation. The results showed a shift of DNA polymerase alpha and beta activities. DNA polymerase alpha, which in controls was found to be the principal replicative enzyme driving DNA synthesis, underwent, upon apoptosis, a large decrease of its activity being replaced by DNA polymerase beta which is believed to be associated with DNA repair. Such a modulation was concomitant with a topographical redistribution of both DNA polymerase alpha and the incorporation of BrdUrd throughout the nucleus. Taken together, these results indicate the occurrence of a dramatic response of the DNA machinery, through a possible common or at least similar behaviour when different cell lines are triggered to apoptosis. Although this possibility requires further investigation, these findings suggest an extreme attempt of the cell undergoing apoptosis to preserve its nuclear environment by switching on a repair/defence mechanism during fragmentation and chromatin margination.

One of the European Union’s (EU) priorities in sports is the holistic development of athletes through combining high-performance sports with higher education. Within the ERASMUS+Sport Collaborative Partnership “More than Gold” (MTG, 603346-EPP-1-2018-1-LV-SPO-SCP), the aim of the empirical research was to clarify and analyse the opinions of high-performance athletes of five Member States on the opportunities for Dual Career (DC) implementation as well as support provision for high-performance athletes within their DC implementation. Survey as the research method was chosen applying questionnaire, interview and focus-group discussion as data collection methods. The research sample included in this work comprised 284 athletes. The data obtained revealed the challenges related to overlapping schedules, long distance from the university to the training venue, and the lack of understanding and flexibility from the academic staff, which was especially challenging in the first academic year. The respondents appreciated the support of DC tutors. Finally, the opinion of experts allowed to identify 9 aspects to be implemented within the DC perspective (e. g., access to educational facilities, tutorship, psychological support). Findings urge to implement DC programmes at higher education institutions (HEIs) comprising DC guidance, flexible study and training schedules, customized curricula, distance learning, proximity of training facilities and sports services, psychological and career support services tailored for elite-athletes. Therefore, the More Than Gold Guidelines for HEIs are crucial for the development of the European DC culture.

Background. We sought to determine the relationship between tricuspid right ventricular (RV) and tricuspid valve (TV) remodeling and late failure of tricuspid annuloplasty. Methods. From May 2009 to December 2015, 423 patients undergoing tricuspid annuloplasty (TA) for functional TR at a single were analyzed. Residual TR was defined TR moderate-or-more at discharge. Recurrent TR was defined TR-moderate-or-more at follow up. RV remodeling was defined RV dysfunction and/or dilatation. Results. Residual TR after TA was recorded in 54. Five-year freedom from TR recurrence was 86.3±2.3% for patients without residual TR vs 57.6±7.6% for patients with residual TR, p<0.001. Evaluating late results of 369 patients without residual TR, following risk factors were identified: preoperative pulmonary pressure, pre RV remodeling, pre TR and TV remodeling, functional mitral regurgitation. Conclusions. Prophylactic tricuspid annuloplasty should be encouraged among surgeons. TA at the time of left-sided valve surgery should take into consideration not only annular size, but also tethering severity and RV remodeling.