Search results for "Senescence"
showing 9 items of 339 documents
Autologu mezenhimālo cilmes šūnu drošuma pārbaude
2018
Šis darbs parādīja, ka no cilvēka un suņa taukaudiem iegūtas cilmes šūnas (ASC) ir līdzīgas pēc morfoloģijas, virsmas marķieru ekspresijas, diferenciācijas potenciāla adipocītos, osteocītos, hondrocītos un imunomodulatīvajām spējām. Tās atbilst minimālajiem mezenhimālo cilmes šūnu definēšanas kritērijiem. Ilgstoša cilvēka ASC in vitro pavairošana izraisīja šūnu novecošanos, ko pierādīja izmaiņas šūnu izskatā, populācijas dubultošanās laika un ar senescenci asociētās β-galaktozidāzes ekspresijas pieaugums, kā arī klonogenitātes un diferenciācijas spējas samazināšanās. Cilvēka ASC kultūrās tika atklātas divas šūnu subpopulācijas ar atšķirīgu relatīvo telomēru garumu un šūnu lielumu. Drošuma p…
Data from: Sex-specific effects of natural and sexual selection on the evolution of life span and ageing in Drosophila simulans
2015
1. Variation in the strength of age-dependent natural selection shapes differences in ageing rates across species and populations. Likewise, sexual selection can promote divergent patterns of senescence across the sexes. However, the effects of these processes on the evolution of ageing have largely been considered independently, and interactions between them are poorly understood. 2. We use experimental evolution to investigate how natural and sexual selection affect life span and ageing in Drosophila simulans. 3. Replicate populations were evolved under lifetime monogamy (relaxed sexual selection) or lifetime polyandry (elevated sexual selection) and at one of two temperatures, 25 °C (rel…
Bcl-xL as a Modulator of Senescence and Aging
2021
Many features of aging result from the incapacity of cells to adapt to stress conditions. When cells are overwhelmed by stress, they can undergo senescence to avoid unrestricted growth of damaged cells. Recent findings have proven that cellular senescence is more than that. A specific grade of senescence promotes embryo development, tissue remodeling and wound healing. However, constant stresses and a weakening immune system can lead to senescence chronicity with aging. The accumulation of senescent cells is directly related to tissue dysfunction and age-related pathologies. Centenarians, the most aged individuals, should accumulate senescent cells and suffer from their deleterious effects,…
Consensus nomenclature for CD8(+) T cell phenotypes in cancer
2015
International audience; Whereas preclinical investigations and clinical studies have established that CD8+ T cells can profoundly affect cancer progression, the underlying mechanisms are still elusive. Challenging the prevalent view that the beneficial effect of CD8+ T cells in cancer is solely attributable to their cytotoxic activity, several reports have indicated that the ability of CD8+ T cells to promote tumor regression is dependent on their cytokine secretion profile and their ability to self-renew. Evidence has also shown that the tumor microenvironment can disarm CD8+ T cell immunity, leading to the emergence of dysfunctional CD8+ T cells. The existence of different types of CD8+ T…
Role of p16ink4a and bmi-1 in oxidative stress-induced premature senescence in human dental pulp stem cells
2017
Las células madre son aquellas células que se dividen asimétricamente para producir una copia de sí mismas y una segunda célula que seguirá su camino hasta convertirse en una célula diferenciada y especializada. Así pues, las células madre que podemos encontrar en el organismo adulto comparten al menos dos características. En primer lugar, se pueden hacer copias idénticas de sí mismas durante largos períodos de tiempo; esta capacidad de proliferar se refiere como auto-renovación a largo plazo. Segundo, pueden dar lugar a tipos celulares maduros que tienen morfologías características y funciones especializadas. Las células madre mesenquimales humanas (CMM) tienen pues un potencial terapéutic…
Fitness in male black grouse (Tetrao tetrix) : effects of life histories and sexual selection on male lifetime mating success
2013
The hypothetical ancestral animal the Urmetazoa: Telomerase activity in sponges [Porifera]
2003
Sponges (Porifera) represent the lowest metazoan phylum, characterized by a pronounced plasticity in the determination of cell lineages, and they are the closest related taxon to the hypothetical ancestral animal, the Urmetazoa, from which the metazoan lineages diverged. In a first approach to elucidate the molecular mechanisms controlling the switch from the cell lineage with a putative indefinite growth capacity to senescent, somatic cells, the activity of the telomerase as an indicator for immortality has been determined. The studies were performed with the marine demosponges Suberites domuncula and Geodia cydonium, in vivo with tissue but also in vitro using the primmorph system. Primmo…
Ar novecošanos saistītu biomarķieru un mtDNS mutāciju izpēte multirezistentās tuberkulozes pacientiem
2020
Darba mērķis: izmantojot biomarķierus, noteikt iespējamo multirezistentās tuberkulozes (MDR-TB) infekcijas saistību ar imūnsistēmas novecošanos un noskaidrot mtDNS variāciju lomu slimības gaitā un farmakoterapijā. Darbā ir analizētas mtDNS daudzuma un telomēru garuma izmaiņas, un apskatīta MDR-TB pacientu ieradumu un citu saistīto faktoru ietekme. MDR-TB pacientiem konstatēts paaugstināts mtDNS kopiju skaits un samazināts telomēru garums salīdzinājumā ar kontroles grupu. Būtiskās izmaiņas vērojamas tikai vīriešu grupā. Biomarķieru izmaiņas iespaidoja arī smēķēšana, terapijas ilgums un saņemto zāļu devu skaits. Identificētas vairākas mtDNS variācijas ar iespējamo ietekmi uz slimības procesie…
Atmospheric brightening counteracts warming‐induced delays in autumn phenology of temperate trees in Europe
2021
Aim: Ongoing climate warming has been widely reported to delay autumn phenology, which in turn impacts carbon, water, energy and nutrient balances at regional and global scales. However, the underlying mechanisms of autumn phenology responses to climate change have not been fully elucidated. The aims of this study were to determine whether brightening that was defined as the increase of surface solar radiation and warming during recent decades affect autumn phenology in opposite directions and explore the underlying mechanisms. Location: Central Europe. Time period: 1950–2016. Major taxa studied: Four dominant European tree species in central Europe: Aesculus hippocastanum, Betula pendula, …