Aerobic exercise showed beneficial influence on cardiovascular systems in aging, and mechanisms underlying vascular adaption remain unclear. Large-conductance Ca2+ -activated K+(BKCa) channels play critical role s in regulating cellular excitability and vascular tone. This study determin ed the effects of aerobic exercise on aging -associated functional changes in BK Ca channels in cerebrovascular myocytes, Male Wistar rats aged 20- 22 mo nths were randomly assigned to sedentary (O -SED), low training frequency (O-EXL), and high training frequency group (O -EXH). Young rats were used as control. Compared to young rats, w hole -cell BK Ca current was decreased, and amplitude of spontaneous transient outward currents were reduced. The open probability and Ca2+/voltage sensitivity of single BK Ca channel were declined in O -SED, accompanied with a reduction of tamoxifen-induced BK Ca activation; the mean open time of BK Ca channels was shortened whereas close time was prolonged. Aerobic exercise training markedly alleviated the aging-associated decline independent of training frequency. Exercise three times rather than five times weekly may be a time and cost-saving training volume required to offer bene ficial effects to offset the functional declines of BK Ca during aging., Na Li, Bailin Liu, Sharon Xiang, Lijun Shi., and Obsahuje bibliografii
Atraktivita, včetně obličeje, je pod vlivem evolučních teorií spojována s mládím, reprodukcí a výběrem potenciálního partnera. Za fyzicky atraktivní je v tomto smyslu považována tvář ženy, která vykazuje jasné pohlavně dimorfní (femininní) znaky, je souměrná (symetrická), s průměrnými proporcemi a eventuelně se ostatním jeví jako povědomá. Valná většina prací zabývající se obličejovou atraktivitou využívá k jejímu zhodnocení statických fotografií tváří mladých žen, jejichž věkový průměr nepřesahuje 25 let. Smyslem předkládané studie není upřít mládí jeho atraktivitu, ale pokouší se najít odpověď na otázku, zdali i tvář ženy nesoucí již známky stárnutí, je ostatními jako fyzicky atraktivní vnímatelná. S tímto cílem bylo k hodnocení v předkládané studii využito obličejových fotografií žen ve věku 50 – 65 let, které z hlediska atraktivity hodnotilo 120 respondentů stratifikovaných dle věku a pohlaví do 4 podskupin – mladší ženy (RZM), mladší muži (RMM), starší ženy (RZS) a starší muži (RMS). Ukázalo se, že spojovat stárnutí s fyzickou atraktivitou je pro hodnotitele nepřirozené a tváře, které podle svých slov označili jako „sympatické“, v nich na první pohled vzbuzovaly dojem dobrého charakteru. Zdá se tedy, že u stárnoucích žen je ostatními ceněna spíše jejich „vnitřní krása“ a tím atraktivita osobní v podobě vlastností, postojů, názorů, hodnot či zájmů, které si respondenti do tváří pro ně atraktivních žen promítají. and Attractiveness, including the face, is under the influence of evolutionary theory associated with youth, reproduction and a mate selection. The physically attractive face in this sense is a woman's face with clear sexually dimorphic (feminine) characters, symmetrical with average proportions and that, which possibly seems familiar to them. The vast majority of work dealing with a facial attractiveness uses for its assessment the static photographs of young women faces, whose average age does not exceed 25 years. The purpose of this study is not to deny the attractiveness of youth, but it is trying to find an answer to the question of whether even woman’s face bearing the signs of aging could be perceived as attractive by others. It was therefore used facial photographs of women aged between 50-65 years for evaluation, which were rated by 120 respondents, stratified by age and sex into four sub-groups - younger women, younger men, older women and older men. It turned out that to associate aging with a physical attractiveness is for evaluators unnatural and faces, which, by their own words, have been marked as „sympathetic“ gave to them the impression of a good character at first glance. It seems therefore, that in aging women is valued by others rather their "inner beauty" and a personal attractiveness in the form of traits, attitudes, beliefs, values or interests that respondents can project to, for them attractive, older women face.
Toxoplasma gondii, a parasite infecting 20-60% of humans in various countries, influences the behaviour of infected animal and human hosts. Infected human subjects have changes in several of Cattell's and Cloninger's personality factors. Recently, three independent studies have shown that Rh-positive subjects are protected against the T. gondii-induced changes of reaction times and increased risk of traffic accidents. Here we searched for evidence of similar effects of RhD phenotype on toxoplasmosis- or aging-associated changes in the personality profile of about 302 blood donors. We found that Rh-positive and Rh-negative subjects responded differently to toxoplasmosis. In addition to the already known effects of toxoplasmosis on novelty seeking, self transcendence, superego strength and protension, we also found effects of RhD phenotype on ego strength, protension, and praxernia, as well as opposite effects of toxoplasmosis on ego strength, praxernia, ergic tension and cooperativeness in Rh-positive and Rh-negative subjects. Moreover, our results indicate that RhD phenotype might influence not only the effect of toxoplasmosis but also the effect of aging on specific personality traits.
Aging is a process drawing attention of many researchers, and at present many theories exists, which try to explain this chain of inevitable events leading to death of organism. In this article we focused our attention on a theory explaining the degenerative changes occurring during aging by the effect of oxygen free radicals. These highly reactive radicals are produced during oxidative phosphorylation in mitochondria. All cellular components appear to be sensitive to oxygen-radical damage. Lipids, proteins and nucleic acids are probably the most susceptible to this injury. Lipoperoxidation of lipids together with cross-linking of proteins with phospholipids and nucleic acids caused changes in membrane fluidity. Mitochondrial DNA coding several subunits of respiratory chain enzymes can be also damaged by these radicals. All these changes together have negative impact on mitochondrial metabolism resulting progressive decrease of the efficiency of oxidative phosphorylation and thus of the whole organism.