Search results for "programme"

Neuronal cell cycle: the neuron itself and its circumstances.

2015

Neurons are usually regarded as postmitotic cells that undergo apoptosis in response to cell cycle reactivation. Nevertheless, recent evidence indicates the existence of a defined developmental program that induces DNA replication in specific populations of neurons, which remain in a tetraploid state for the rest of their adult life. Similarly, de novo neuronal tetraploidization has also been described in the adult brain as an early hallmark of neurodegeneration. The aim of this review is to integrate these recent developments in the context of cell cycle regulation and apoptotic cell death in neurons. We conclude that a variety of mechanisms exists in neuronal cells for G1/S and G2/M check…

Bax-derived membrane-active peptides act as potent and direct inducers of apoptosis in cancer cells.

2011

SUMMARYAlthough many cancer cells are primed for apoptosis, they usually develop resistance to cell death at multiple levels. Permeabilization of the outer mitochondrial membrane, which is mediated by proapoptotic Bcl-2 family members like Bax, is considered as a point-of-no-return for initiating apoptotic cell death. This crucial role has placed Bcl-2 family proteins as recurrent targets for anticancer drug development. Here, we propose and demonstrate a new concept based on using minimal active version of Bax to induce cell death independently of endogenous Bcl-2 proteins. We show that membrane-active segments of Bax can directly induce the release of mitochondria-residing apoptogenic fac…

Étude sur les réformes curriculaires par l'approche par compétences en Afrique

2009

Cette étude vise trois objectifs : réaliser un état des lieux des processus de réformes curriculaires en éducation de base en Afrique pour identifier les problèmes rencontrés, les résultats positifs et les "bonnes pratiques", aider les responsables des systèmes éducatifs à prendre des mesures pertinentes et accompagner les réformes et enfin aider les bailleurs de fonds à mieux comprendre les effets de leur aide et à mieux cibler les projets de réforme en termes de coût et d'efficacité à tous les niveaux des systèmes éducatifs impliqués.

Ietvarprogramma Apvārsnis 2020 un jaunākās Open Access nostādnes Eiropā

2012

Ziņojumā, kas sagatavots Open Access nedēļas semināram " Brīvpieejas e-resursu puiblicēšana: iespējas un attīstība" (2012.g. 26.oktobris), sniegta informācija par Eiropas Komisijas 2011. gadā publicētajos ieteikumos un paziņojumos ietvertajām Open Access nostādnēm saistībā ar jauno ES pētniecības un inovāciju finansēšanas programmu 2014.-2020. gadam Apvārsnis 2020. Prezentācijā iekļauts arī programmas Apvārsnis 2020 raksturojums un tajā paredzētās prasības zinātnisko rakstu publicēšanai brīvpieejā.

Current and emerging developments in subseasonal to decadal prediction

2020

Weather and climate variations on subseasonal to decadal time scales can have enormous social, economic, and environmental impacts, making skillful predictions on these time scales a valuable tool for decision-makers. As such, there is a growing interest in the scientific, operational, and applications communities in developing forecasts to improve our foreknowledge of extreme events. On subseasonal to seasonal (S2S) time scales, these include high-impact meteorological events such as tropical cyclones, extratropical storms, floods, droughts, and heat and cold waves. On seasonal to decadal (S2D) time scales, while the focus broadly remains similar (e.g., on precipitation, surface and upper-…

Artesunate Activates Mitochondrial Apoptosis in Breast Cancer Cells via Iron-catalyzed Lysosomal Reactive Oxygen Species Production

2011

The antimalarial agent artesunate (ART) activates programmed cell death (PCD) in cancer cells in a manner dependent on the presence of iron and the generation of reactive oxygen species. In malaria parasites, ART cytotoxicity originates from interactions with heme-derived iron within the food vacuole. The analogous digestive compartment of mammalian cells, the lysosome, similarly contains high levels of redox-active iron and in response to specific stimuli can initiate mitochondrial apoptosis. We thus investigated the role of lysosomes in ART-induced PCD and determined that in MCF-7 breast cancer cells ART activates lysosome-dependent mitochondrial outer membrane permeabilization. ART impac…

p62: Friend or Foe? Evidences for OncoJanus and NeuroJanus Roles

2020

p62 is a versatile protein involved in the delicate balance between cell death and survival, which is fundamental for cell fate decision in the context of both cancer and neurodegenerative diseases. As an autophagy adaptor, p62 recognizes polyubiquitin chains and interacts with LC3, thereby targeting the selected cargo to the autophagosome with consequent autophagic degradation. Beside this function, p62 behaves as an interactive hub in multiple signalling including those mediated by Nrf2, NF-κB, caspase-8, and mTORC1. The protein is thus crucial for the control of oxidative stress, inflammation and cell survival, apoptosis, and metabolic reprogramming, respectively. As a multifunctional pr…

Autophagy in development and stress responses of plants.

2006

The uptake and degradation of cytoplasmic material by vacuolar autophagy in plants has been studied extensively by electron microscopy and shown to be involved in developmental processes such as vacuole formation, deposition of seed storage proteins and senescence, and in the response of plants to nutrient starvation and to pathogens. The isolation of genes required for autophagy in yeast has allowed the identification of many of the corresponding Arabidopsis genes based on sequence similarity. Knockout mutations in some of these Arabidopsis genes have revealed physiological roles for autophagy in nutrient recycling during nitrogen deficiency and in senescence. Recently, markers for monitor…

Involvement of PAR-4 in Cannabinoid-Dependent Sensitization of Osteosarcoma Cells to TRAIL-Induced Apoptosis

2014

The synthetic cannabinoid WIN 55,212-2 is a potent cannabinoid receptor agonist with anticancer potential. Experiments were performed to determine the effects of WIN on proliferation, cell cycle distribution, and programmed cell death in human osteosarcoma MG63 and Saos-2 cells. Results show that WIN induced G2/M cell cycle arrest, which was associated with the induction of the main markers of ER stress (GRP78, CHOP and TRB3). In treated cells we also observed the conversion of the cytosolic form of the autophagosome marker LC3-I into LC3-II (the lipidated form located on the autophagosome membrane) and the enhanced incorporation of monodansylcadaverine and acridine orange, two markers of t…

2020

BAG3, a multifunctional HSP70 co-chaperone and anti-apoptotic protein that interacts with the ATPase domain of HSP70 through its C-terminal BAG domain plays a key physiological role in cellular proteostasis. The HSP70/BAG3 complex determines the levels of a large number of selective client proteins by regulating their turnover via the two major protein degradation pathways, i.e. proteasomal degradation and macroautophagy. On the one hand, BAG3 competes with BAG1 for binding to HSP70, thereby preventing the proteasomal degradation of its client proteins. By functionally interacting with HSP70 and LC3, BAG3 also delivers polyubiquitinated proteins to the autophagy pathway. BAG3 exerts a numbe…