604 research outputs found
La globalización alternativa y los 'novísimos' movimientos sociales
Las dos últimas décadas han sido testigos del surgimiento de un nuevo ciclo global de acción colectiva, organizada a través del internet y que se ha hecho visible durante protestas masivas, pero también ha sido configurado localmente por diversas organizaciones, redes, plataformas, y grupos. Con base en dos casos específicos en dos ciudades ibéricas –Barcelona y Lisboa–, argumentamos que este ciclo de protestas ha dado lugar a nuevos tipos de movimientos a los que aquí nos referimos como los ‘novísimos movimientos sociales’. Analizamos aspectos específicos de cada caso, pero también discutimos sus dimensiones europeas y globales. El artículo enfatiza el papel de la juventud, discute las características asociadas con la participación de los jóvenes en los ‘novísimos’ movimientos. Después de una breve introducción a la investigación sobre este tema, centrándonos en el surgimiento del ‘movimiento de la 'globalización alternativa' o ‘en contra de la globalización corporativa’ y sus implicaciones teóricas asociadas, ofrecemos una descripción de cuatro acontecimientos de protesta en Barcelona y Lisboa. A continuación, analizamos los contextos locales en los que se fundamentan estos acontecimientos. Finalmente, discutimos las principales características de los ‘novísimos movimientos sociales’, analizando los vínculos entre Barcelona y Lisboa y el contexto internacional más amplio que les da forma, prestando especial atención en las dinámicas contemporáneas de formación de redes
Cooperation between COA6 and SCO2 in COX2 maturation during cytochrome c oxidase assembly links two mitochondrial cardiomyopathies.
Three mitochondria-encoded subunits form the catalytic core of cytochrome c oxidase, the terminal enzyme of the respiratory chain. COX1 and COX2 contain heme and copper redox centers, which are integrated during assembly of the enzyme. Defects in this process lead to an enzyme deficiency and manifest as mitochondrial disorders in humans. Here we demonstrate that COA6 is specifically required for COX2 biogenesis. Absence of COA6 leads to fast turnover of newly synthesized COX2 and a concomitant reduction in cytochrome c oxidase levels. COA6 interacts transiently with the copper-containing catalytic domain of newly synthesized COX2. Interestingly, similar to the copper metallochaperone SCO2, loss of COA6 causes cardiomyopathy in humans. We show that COA6 and SCO2 interact and that corresponding pathogenic mutations in each protein affect complex formation. Our analyses define COA6 as a constituent of the mitochondrial copper relay system, linking defects in COX2 metallation to cardiac cytochrome c oxidase deficiency
Situated solidarities and the practice of scholar-activism
Drawing on an analysis of an ongoing collaboration with rural peasant movements in Bangladesh, we explore the possibility of forging solidarity through practices of scholar-activism. In so doing, we consider the practice of reflexivity, reconsider forms of solidarity, and draw on the concept of convergence spaces as a way to envision sites of possibility. We mobilize the notion of situated solidarities to propose an alternative form of reflexive practice in scholarship. We then posit that there are six ‘practices’ that provide a useful schematic for thinking through the opportunities for the construction of these solidaritie
SEDLIN Forms Homodimers: Characterisation of SEDLIN Mutations and Their Interactions with Transcription Factors MBP1, PITX1 and SF1
BACKGROUND: SEDLIN, a 140 amino acid subunit of the Transport Protein Particle (TRAPP) complex, is ubiquitously expressed and interacts with the transcription factors c-myc promoter-binding protein 1 (MBP1), pituitary homeobox 1 (PITX1) and steroidogenic factor 1 (SF1). SEDLIN mutations cause X-linked spondyloepiphyseal dysplasia tarda (SEDT). METHODOLOGY/PRINCIPAL FINDINGS: We investigated the effects of 4 missense (Asp47Tyr, Ser73Leu, Phe83Ser and Val130Asp) and the most C-terminal nonsense (Gln131Stop) SEDT-associated mutations on interactions with MBP1, PITX1 and SF1 by expression in COS7 cells. Wild-type SEDLIN was present in the cytoplasm and nucleus and interacted with MBP1, PITX1 and SF1; the SEDLIN mutations did not alter these subcellular localizations or the interactions. However, SEDLIN was found to homodimerize, and the formation of dimers between wild-type and mutant SEDLIN would mask a loss in these interactions. A mammalian SEDLIN null cell-line is not available, and the interactions between SEDLIN and the transcription factors were therefore investigated in yeast, which does not endogenously express SEDLIN. This revealed that all the SEDT mutations, except Asp47Tyr, lead to a loss of interaction with MBP1, PITX1 and SF1. Three-dimensional modelling studies of SEDLIN revealed that Asp47 resides on the surface whereas all the other mutant residues lie within the hydrophobic core of the protein, and hence are likely to affect the correct folding of SEDLIN and thereby disrupt protein-protein interactions. CONCLUSIONS/SIGNIFICANCE: Our studies demonstrate that SEDLIN is present in the nucleus, forms homodimers and that SEDT-associated mutations cause a loss of interaction with the transcription factors MBP1, PITX1 and SF1
Incidence rates of progressive childhood encephalopathy in Oslo, Norway: a population based study
<p>Abstract</p> <p>Background</p> <p>Progressive encephalopathy (PE) in children is a heterogeneous group of diseases mainly composed of metabolic diseases, but it consists also of neurodegenerative disorders where neither metabolic nor other causes are found. We wanted to estimate the incidence rate and aetiology of PE, as well as the age of onset of the disease.</p> <p>Methods</p> <p>We included PE cases born between 1985 and 2003, living in Oslo, and registered the number presenting annually between 1985 and 2004. Person-years at risk between 0 and 15 years were based on the number of live births during the observation period which was divided into four 5-year intervals. We calculated incidence rates according to age at onset which was classified as neonatal (0–4 weeks), infantile (1–12 months), late infantile (1–5 years), and juvenile (6–12 years).</p> <p>Results</p> <p>We found 84 PE cases representing 28 diagnoses among 1,305,997 person years, giving an incidence rate of 6.43 per 100,000 person years. The age-specific incidence rates per 100,000 were: 79.89 (<1 year), 8.64 (1–2 years), 1.90 (2–5 years), and 0.65 (>5 years). 66% (55/84) of the cases were metabolic, 32% (27/54) were neurodegenerative, and 2% (2/84) had HIV encephalopathy. 71% (60/84) of the cases presented at < 1 year, 24% (20/84) were late infantile presentations, and 5% (4/84) were juvenile presentations. Neonatal onset was more common in the metabolic (46%) (25/55) compared to the neurodegenerative group (7%) (2/27). 20% (17/84) of all cases were classified as unspecified neurodegenerative disease.</p> <p>Conclusion</p> <p>The overall incidence rate of PE was 6.43 per 100,000 person years. There was a strong reduction in incidence rates with increasing age. Two-thirds of the cases were metabolic, of which almost half presented in the neonatal period.</p
A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition
Ruthenium(II) polypyridyl complexes can intercalate DNA with high affinity and prevent cell
proliferation; however, the direct impact of ruthenium-based intercalation on cellular DNA replication
remains unknown. Here we show the multi-intercalator [Ru(dppz)2(PIP)]2+ (dppz =
dipyridophenazine, PIP = 2-(phenyl)imidazo[4,5-f][1,10]phenanthroline) immediately stalls
replication fork progression in HeLa human cervical cancer cells. In response to this replication
blockade, the DNA damage response (DDR) cell signalling network is activated, with checkpoint
kinase 1 (Chk1) activation indicating prolonged replication-associated DNA damage, and cell
proliferation is inhibited by G1-S cell-cycle arrest. Co-incubation with a Chk1 inhibitor achieves
synergistic apoptosis in cancer cells, with a significant increase in phospho(Ser139) histone H2AX (γ-
H2AX) levels and foci indicating increased conversion of stalled replication forks to double-strand
breaks (DSBs). Normal human epithelial cells remain unaffected by this concurrent treatment.
Furthermore, pre-treatment of HeLa cells with [Ru(dppz)2(PIP)]2+ before external beam ionising
radiation results in a supra-additive decrease in cell survival accompanied by increased γ-H2AX
expression, indicating the compound functions as a radiosensitizer. Together, these results indicate ruthenium-based intercalation can block replication fork progression and demonstrate how these
DNA-binding agents may be combined with DDR inhibitors or ionising radiation to achieve more
efficient cancer cell killing
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