18 research outputs found
Mining Condensed Spatial Co-Location Patterns
The discovery of co-location patterns among spatial events is an important task in spatial data mining. We introduce a new kind of spatial co-location patterns, named condensed spatial co-location patterns, that can be considered as a lossy compressed representation of all the co-location patterns. Each condensed pattern is the representative, and a superset, of a group of spatial co-location patterns in the full set of patterns such that the difference between the interestingness measure of the representative and the measures of the patterns belonging to the associated group are negligible. Our preliminary experiments show that condensed spatial co-location patterns are less sensitive to parameter changes and more robust in presence of missing data than closed spatial co-location patterns
Chelation of Lysosomal Iron Protects Dopaminergic SH-SY5Y Neuroblastoma Cells from Hydrogen Peroxide Toxicity by Precluding Autophagy and Akt Dephosphorylation
In human neuroblastoma SH-SY5Y cells, hydrogen peroxide (H(2)O(2), 200\u3bcM) rapidly
(< 5 min) induced autophagy, as shown by processing and vacuolar relocation of
light chain 3(LC3). Accumulation of autophagosome peaked at 30 min of H(2)O(2)
exposure. The continuous presence of H(2)O(2) eventually (at > 60 min) caused
autophagy-dependent annexin V-positive cell death. However, the cells exposed to
H(2)O(2) for 30 min and then cultivated in fresh medium could recover and grow,
despite ongoing autophagy. H(2)O(2) rapidly (5 min) triggered the formation of
dichlorofluorescein-sensitive HO(\ub7)-free radicals within mitochondria, whereas
the mitochondria-associated oxidoradicals revealed by MitoSox (O(2)(\ub7-)) became
apparent after 30 min of exposure to H(2)O(2). 3-Methyladenine inhibited
autophagy and cell death, but not the generation of HO(\ub7). Genetic silencing of
beclin-1 prevented bax- and annexin V-positive cell death induced by H(2)O(2),
confirming the involvement of canonical autophagy in peroxide toxicity. The
lysosomotropic iron chelator deferoxamine (DFO) prevented the mitochondrial
generation of both HO(.) and O(2)(\ub7-) and suppressed the induction of autophagy
and of cell death by H(2)O(2). Upon exposure to H(2)O(2), Akt was intensely
phosphorylated in the first 30 min, concurrently with mammalian target of
rapamycin inactivation and autophagy, and it was dephosphorylated at 2 h, when >
50% of the cells were dead. DFO did not impede Akt phosphorylation, which
therefore was independent of reactive oxygen species (ROS) generation but
inhibited Akt dephosphorylation. In conclusion, exogenous H(2)O(2) triggers two
parallel independent pathways, one leading to autophagy and autophagy-dependent
apoptosis, the other to transient Akt phosphorylation, and both are inhibited by
DFO. The present work establishes HO(\ub7) as the autophagy-inducing ROS and
highlights the need for free lysosomal iron for its production within
mitochondria in response to hydrogen peroxide
timeClip: pathway analysis for time course data without replicates
none6noneMartini P.; Sales G.; Calura E.; Cagnin S.; Chiogna M.; Romualdi C.Martini, Paolo; Sales, Gabriele; Calura, Enrica; Cagnin, Stefano; Chiogna, Monica; Romualdi, Chiar
SOYBEAN YIELD COMPONENTS IN DIFFERENT SOWING PERIODS IN THE WESTERN OF STATE OF BAHIA
Yield is closely linked to the plant yield components and depend directly of the genotype interaction with the environment. Essays were installed in the experimental field of the Bahia Foundation in the Maria Gabriela farm in the county of Sao Desiderio - BA in the year 2006-2007. The aim of this work was to evaluate yield components of five soybean cultivars with different maturation cycles indicated for the Western Region of Bahia in different sowing periods. The experimental design was in random blocks in 4 x 5 factorial scheme (four sowing periods: Ep1 first - 11/29/2006, Ep2 second - 12/14/2006, Ep3 third - 12/28/2007, Ep4 fourth - 01/12/2007 and five cultivars: M-SOY 8411, BRS Corisco, BRS 263 [Diferente], BRS Barreiras e M-SOY 9350) with four repetitions. The following characteristics were evaluated: total number of pods per plant, total number of beans per plant, mass of 1000 beans and yield. Plant yield components, total number of pods per plant, total number of beans per plant, mass of 1000 beans, reduced with sowing delay and showed compensation effect between cultivars and sowing periods. Late sowing Ep3 (28/12/2006) and Ep4 (12/01/2007) were not favourable to raise yield of soybean in the Western Region of Bahia
The fine tuning of metabolism, autophagy and differentiation during in vitro myogenesis
Although the mechanisms controlling skeletal muscle homeostasis have been identified, there is a lack of knowledge of the integrated dynamic processes occurring during myogenesis and their regulation. Here, metabolism, autophagy and differentiation were concomitantly analyzed in mouse muscle satellite cell (MSC)-derived myoblasts and their cross-talk addressed by drug and genetic manipulation. We show that increased mitochondrial biogenesis and activation of mammalian target of rapamycin complex 1 inactivation-independent basal autophagy characterize the conversion of myoblasts into myotubes. Notably, inhibition of autophagic flux halts cell fusion in the latest stages of differentiation and, conversely, when the fusion step of myocytes is impaired the biogenesis of autophagosomes is also impaired. By using myoblasts derived from p53 null mice, we show that in the absence of p53 glycolysis prevails and mitochondrial biogenesis is strongly impaired. P53 null myoblasts show defective terminal differentiation and attenuated basal autophagy when switched into differentiating culture conditions. In conclusion, we demonstrate that basal autophagy contributes to a correct execution of myogenesis and that physiological p53 activity is required for muscle homeostasis by regulating metabolism and by affecting autophagy and differentiation