This article deals with the issue of overtraining among elite adolescent athletes. The aim of our study was to examine the relationship between certain personality traits, as perfectionism, extraversion, neuroticism and other Big 5 traits and subjective perception of training load (which is one of the best indicator of overtraining syndrome). We also focused on the relationship between a perceived training difficulty and perceived training load too find out, if there is some kind of integral relationship. To collect data we used a questionnaire, which were given to adolescent elite athletes playing team sports in a mid-season period. The results show significant relationship between perceived training load and overall perfectionism (r=0.189, p<0.001), extraversion (r=-0.241, p<0.001), neuroticism (r=0.343, p<0.001) and consciousness (r=-0.287, p<0.001). After the closer examination we found an interesting relation between single dimension of perfectionism and perceived training load, suggesting the contribution of maladaptive perfectionism on development of overtraining syndrome. Besides that, we differentiated athletes into two groups, according to the level of perceived training difficulty. Those, who perceived training as difficult to exhausting (M=2,19, SD=0.50) were significantly higher than low to medium group (M=1.99, SD=0.47) in the perceived training load t(178)=-0.894, p=0.007. Those results extend our knowledge of overtraining topic and can be used in coaching practice to help identify athletes with higher risk of overtraining, or even prevent these states among young athletes before they occur. Hereby results suggest the importance of psychological aspects in sport preparation.
The article deals with structure and performance-related changes occurring in the beginning of puberty in relation to ice-hockey players of the older pupil category. 20 male players born in 2005 and in 2006 of corresponding biological age underwent measuring of their somatic parameters, balance and specific performance on ice. To evaluate the maturity age, the Roche-Wainer-Thissen method was used; moreover, the Star excursion balance test (SEBT) was used to assess the balance and the Illinois agility test (IAT) without a puck was used to assess the performance on ice. The results show that players born in 2005 show bigger structural changes in comparison with those born in 2006; nevertheless, no differences in somatotypology were found. As far as performance is concerned, the players born in 2005 were faster in the IAT while those born in 2006 displayed bigger reaches in SEBT – specifically in the anteromedial (AM), medial (M), posteromedial (PM), posterior (P), posterolateral (PL), anterolateral (AL) direction and the composite score (COMP). These findings strongly indicate that IAT depends on the production of strength which was bigger due to the structural changes. The SEBT results of the players born in 2005 may have been influenced by the puberty spurt during which adolescents’ coordination stagnates due to a worsened postural control. The growth of body proportionality may have led to lever changes and to ineffective motor control while dealing with a new motor task as well. Another reason for the above-mentioned may also be muscle shortening.
Based on the research review, fascia-oriented training may positively influence sports performance. Its component focused on the “catapult” mechanism can increase the capability of the connective tissue to store and release kinetic energy, which is involved in various movement actions, activities and skills including the jumping skills in volleyball. The study was conducted to assess the effect of the 6-month fascia-oriented training on the height of the vertical jump in well-trained junior female volleyball players. 16 players (age 17.31 ± 0.98; height 173 ± 5.26; weight 65.25 ± 6.75), members of one team competing in the national league, were randomly assigned for the training group (TG) and control group (CG). TG participated in a supervised 25-minute fascia-oriented training twice a week for six months. To measure the height of the jump, the force plate Bertec FP6012-15-4000 was used. Three testing measures were executed: pre-test, mid-test and post-test with three trials of the standing vertical countermovement jump with all arm movement. The study presupposed that after three months, the height of jump may rise slightly more in TG than in CG. After six months, a statistically significant increase was expected in TG compared to CG. Based on the results of the study, we conclude that the 6-month fascia-oriented training focused on the development of the height of vertical jump in well-trained junior volleyball players neither complied with the assumed dynamics in changes nor was statistically significantly beneficial. However, the dynamics of the changes indicate that fascia-oriented training may positively influence the stability and efficiency of the jumping performance during the game season.
Cílem studie bylo popsat souvislosti psychické adaptace dvanáctiletých až osmnáctiletých španělských adolescentů (N = 456, M = 14.61; SD = 0.53; 56 % dívek) pomocí modelu rodinných procesů. Byly administrovány sebeposuzovací škály měřící vnímání rodičovského konfliktu (zkrácená verze metody Children's Perception of Interparental Conflict Scale), internalizované a externalizované chování (Youth Self Report) a rodičovské chování (Child's Reports of Parental Behavior Inventory). Model vycházející z teorie rodinného systému byl ověřován prostřednictvím strukturního modelu (SEM). Bylo zjištěno, že v jednoduchém strukturním modelu je adolescenty vnímaná hostilita a tvrdé trestání u obou rodičů částečným mediátorem vztahu mezi rodičovským konfliktem a internalizovaným, ale i externalizovaným chováním adolescentů. Dále bylo v rámci jednoduchého modelu zjištěno, že vnímaná rodičovská opora a otevřená komunikace částečně zmírňuje dopad rodičovského konfliktu na internalizované a externalizované chování. Při ověřování komplexního strukturního modelu však již nebyla nalezena podpora pro mediaci vztahu mezi rodičovským konfliktem a adaptací adolescentů prostřednictvím rodičovského chování. Výsledky tak nejsou v souladu s tzv. hypotézou přelévání, ale spíše ukazují spíše na vzájemnou souvislost rodičovského chování a konfliktu mezi rodiči, které pak hrají významnou roli v míře adaptace adolescentů.
The aim of this study was to examine the family process model of adolescent psychological adjustment in a sample of 12 to 18 year-old 456 Spanish adolescents (M = 14.61; SD = 0.53; 56 % of females). The self-report scales administered to the adolescents included a short version of Children's Perception of Interparental Conflict Scale, six subscales of Youth Self Report, and two subscales of Child's Reports of Parental Behavior Inventory. Structural equation modeling (SEM) was used to examine the family-system-theory based model. This model suggested that 1) adolescent perception of marital conflict affects adolescent psychological adjustment; 2) this association can be explained by adolescent perception of parental hostility and harsh punishment by both parents, and 3) the negative association can be buffered by adolescent perception of parental support and open communication. The results show that parental hostility and harsh punishment by both parents partially mediated the association between marital conflict and adolescent internalizing and externalizing behaviors in a simple mediation model. Next, parental support and open communication partially buffered the relation between marital conflict and adolescent internalizing and externalizing behaviors in a simple mediation model. However, using a complex model of structural equation modeling we did not find support for the model where parenting mediates the relationship between marital conflict and adolescent adjustment. Our findings do not support the usual direction of the spillover hypothesis but indicate that parenting is linked to marital conflict and both of them play an important role in adolescent adjustment.
- MeSH
- adaptace psychologická MeSH
- chování mladistvých * psychologie MeSH
- konflikt (psychologie) MeSH
- konflikt v rodině * psychologie MeSH
- lidé MeSH
- manželství psychologie MeSH
- matky MeSH
- mladiství MeSH
- otcové MeSH
- psychologie adolescentů MeSH
- psychometrie MeSH
- rodičovství MeSH
- sociální přizpůsobení MeSH
- vztahy mezi rodiči a dětmi * MeSH
- zpráva o sobě MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- práce podpořená grantem MeSH
- MeSH
- fosforylace MeSH
- lidé MeSH
- replikační protein C * MeSH
- Saccharomyces cerevisiae - proteiny metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- komentáře MeSH
- zprávy MeSH
The incorporation of histone H3 with an acetylated lysine 56 (H3K56ac) into the nucleosome is important for chromatin remodeling and serves as a marker of new nucleosomes during DNA replication and repair in yeast. However, in human cells, the level of H3K56ac is greatly reduced, and its role during the cell cycle is controversial. Our aim was to determine the potential of H3K56ac to regulate cell cycle progression in different human cell lines. A significant increase in the number of H3K56ac foci, but not in H3K56ac protein levels, was observed during the S and G2 phases in cancer cell lines, but was not observed in embryonic stem cell lines. Despite this increase, the H3K56ac signal was not present in late replication chromatin, and H3K56ac protein levels did not decrease after the inhibition of DNA replication. H3K56ac was not tightly associated with the chromatin and was primarily localized to active chromatin regions. Our results support the role of H3K56ac in transcriptionally active chromatin areas but do not confirm H3K56ac as a marker of newly synthetized nucleosomes in DNA replication.
- MeSH
- buněčný cyklus genetika fyziologie MeSH
- chromatin metabolismus MeSH
- G2 fáze genetika MeSH
- histony metabolismus MeSH
- HL-60 buňky MeSH
- hmotnostní spektrometrie MeSH
- lidé MeSH
- nukleozomy metabolismus MeSH
- replikace DNA genetika fyziologie MeSH
- S fáze genetika MeSH
- Saccharomyces cerevisiae - proteiny genetika metabolismus MeSH
- Saccharomyces cerevisiae genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The MAGE (Melanoma-associated antigen) protein family members are structurally related to each other by a MAGE-homology domain comprised of 2 winged helix motifs WH/A and WH/B. This family specifically evolved in placental mammals although single homologs designated NSE3 (non-SMC element) exist in most eukaryotes. NSE3, together with its partner proteins NSE1 and NSE4 form a tight subcomplex of the structural maintenance of chromosomes SMC5-6 complex. Previously, we showed that interactions of the WH/B motif of the MAGE proteins with their NSE4/EID partners are evolutionarily conserved (including the MAGEA1-NSE4 interaction). In contrast, the interaction of the WH/A motif of NSE3 with NSE1 diverged in the MAGE paralogs. We hypothesized that the MAGE paralogs acquired new RING-finger-containing partners through their evolution and form MAGE complexes reminiscent of NSE1-NSE3-NSE4 trimers. In this work, we employed the yeast 2-hybrid system to screen a human RING-finger protein library against several MAGE baits. We identified a number of potential MAGE-RING interactions and confirmed several of them (MDM4, PCGF6, RNF166, TRAF6, TRIM8, TRIM31, TRIM41) in co-immunoprecipitation experiments. Among these MAGE-RING pairs, we chose to examine MAGEA1-TRIM31 in detail and showed that both WH/A and WH/B motifs of MAGEA1 bind to the coiled-coil domain of TRIM31 and that MAGEA1 interaction stimulates TRIM31 ubiquitin-ligase activity. In addition, TRIM31 directly binds to NSE4, suggesting the existence of a TRIM31-MAGEA1-NSE4 complex reminiscent of the NSE1-NSE3-NSE4 trimer. These results suggest that MAGEA1 functions as a co-factor of TRIM31 ubiquitin-ligase and that the TRIM31-MAGEA1-NSE4 complex may have evolved from an ancestral NSE1-NSE3-NSE4 complex.
- MeSH
- biologické modely MeSH
- chromatografie kapalinová MeSH
- domény RING-prstů MeSH
- HEK293 buňky MeSH
- imunoprecipitace MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- multimerizace proteinu MeSH
- multiproteinové komplexy metabolismus MeSH
- nádorové proteiny chemie metabolismus MeSH
- peptidové fragmenty chemie metabolismus MeSH
- peptidy chemie metabolismus MeSH
- sekvence aminokyselin MeSH
- tandemová hmotnostní spektrometrie MeSH
- techniky dvojhybridového systému MeSH
- transportní proteiny metabolismus MeSH
- ubikvitinligasy chemie metabolismus MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cajal bodies are important nuclear structures containing proteins that preferentially regulate RNA-related metabolism. We investigated the cell-type specific nuclear distribution of Cajal bodies and the level of coilin, a protein of Cajal bodies, in non-irradiated and irradiated human tumor cell lines and embryonic stem (ES) cells. Cajal bodies were localized in different nuclear compartments, including DAPI-poor regions, in the proximity of chromocenters, and adjacent to nucleoli. The number of Cajal bodies per nucleus was cell cycle-dependent, with higher numbers occurring during G2 phase. Human ES cells contained a high coilin level in the nucleoplasm, but coilin-positive Cajal bodies were also identified in nuclei of mouse and human ES cells. Coilin, but not SMN, recognized UVA-induced DNA lesions, which was cell cycle-independent. Treatment with γ-radiation reduced the localized movement of Cajal bodies in many cell types and GFP-coilin fluorescence recovery after photobleaching was very fast in nucleoplasm in comparison with GFP-coilin recovery in DNA lesions. By contrast, nucleolus-localized coilin displayed very slow fluorescence recovery after photobleaching, which indicates very slow rates of protein diffusion, especially in nucleoli of mouse ES cells.
- MeSH
- buněčné jádro genetika metabolismus účinky záření MeSH
- buněčné linie MeSH
- buňky K562 MeSH
- Cajalova tělíska genetika metabolismus účinky záření MeSH
- DNA genetika účinky záření MeSH
- G2 fáze genetika MeSH
- HeLa buňky MeSH
- jaderné proteiny genetika metabolismus MeSH
- lidé MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- rekombinantní fúzní proteiny genetika metabolismus MeSH
- ultrafialové záření škodlivé účinky MeSH
- záření gama škodlivé účinky MeSH
- zelené fluorescenční proteiny genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
DLC-type layers offer a good potential for application in medicine, due to their excellent tribological properties, chemical resistance, and bio-inert character. The presented study has verified the possibility of alloying DLC layers with titanium, with coatings containing three levels of titanium concentration prepared. Titanium was present on the surface mainly in the form of oxides. Its increasing concentration led to increased presence of titanium carbide as well. The behavior of the studied systems was stable during exposure in a physiological saline solution. Electrochemical impedance spectra practically did not change with time. Alloying, however, changed the electrochemical behavior of coated systems in a significant way: from inert surface mediating only exchange reactions of the environment in the case of unalloyed DLC layers to a response corresponding rather to a passive surface in the case of alloyed specimens. The effect of DLC layers alloying with titanium was tested by the interaction with a simulated body fluid, during which precipitation of a compound containing calcium and phosphorus--basic components of the bone apatite--occurred on all doped specimens, in contrast to pure DLC. The results of the specimens' surface colonization with cells test proved the positive effect of titanium in the case of specimens with a medium and highest content of this element.
- MeSH
- biokompatibilní potahované materiály chemie MeSH
- biomedicínské technologie MeSH
- elektrická impedance MeSH
- fosfor chemie MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- povrchové vlastnosti MeSH
- slitiny chemie MeSH
- tělesné tekutiny chemie MeSH
- testování materiálů MeSH
- titan chemie MeSH
- uhlík chemie MeSH
- vápník chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Tumor growth and cancer development are considered clear examples of Darwinian selection, whereby random mutational events in heterogeneous cancer cell populations that best fit the selective microenvironment are preferred.(1) As a result, cancer cells evolve resistance to apoptosis, hide from immune surveillance and acquire the ability to invade other organs. Cancer cells, however, are not necessarily passive subjects of selection; they can actively subvert the host tissue to provide a favorable habitat for their growth. Recent findings by Calon et al. convincingly demonstrate that transforming growth factor-β-induced secretion of interleukin 11 by tumor stromal fibroblasts is a necessary prerequisite for the development of distant metastases in colorectal carcinoma. Thus, understanding the complex molecular feedback loops between cancer cells and the surrounding microenvironment (i.e., the tumor-associated stroma or invaded host tissue) should aid the identification of useful molecular targets for improving clinical management of advanced metastatic cancers.
- Publikační typ
- časopisecké články MeSH
