12 research outputs found

    Treatment Outcomes of Multidrug-Resistant Tuberculosis: A Systematic Review and Meta-Analysis

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    BACKGROUND:Treatment outcomes for multidrug-resistant Mycobacterium Tuberculosis (MDRTB) are generally poor compared to drug sensitive disease. We sought to estimate treatment outcomes and identify risk factors associated with poor outcomes in patients with MDRTB. METHODOLOGY/PRINCIPAL FINDINGS:We performed a systematic search (to December 2008) to identify trials describing outcomes of patients treated for MDRTB. We pooled appropriate data to estimate WHO-defined outcomes at the end of treatment and follow-up. Where appropriate, pooled covariates were analyzed to identify factors associated with worse outcomes. Among articles identified, 36 met our inclusion criteria, representing 31 treatment programmes from 21 countries. In a pooled analysis, 62% [95% CI 57-67] of patients had successful outcomes, while 13% [9]-[17] defaulted, 11% [9]-[13] died, and 2% [1]-[4] were transferred out. Factors associated with worse outcome included male gender 0.61 (OR for successful outcome) [0.46-0.82], alcohol abuse 0.49 [0.39-0.63], low BMI 0.41[0.23-0.72], smear positivity at diagnosis 0.53 [0.31-0.91], fluoroquinolone resistance 0.45 [0.22-0.91] and the presence of an XDR resistance pattern 0.57 [0.41-0.80]. Factors associated with successful outcome were surgical intervention 1.91 [1.44-2.53], no previous treatment 1.42 [1.05-1.94], and fluoroquinolone use 2.20 [1.19-4.09]. CONCLUSIONS/SIGNIFICANCE:We have identified several factors associated with poor outcomes where interventions may be targeted. In addition, we have identified high rates of default, which likely contributes to the development and spread of MDRTB

    A fractal nature for polymerized laminin

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    Polylaminin (polyLM) is a non-covalent acid-induced nano- and micro-structured polymer of the protein laminin displaying distinguished biological properties. Polylaminin stimulates neuritogenesis beyond the levels achieved by ordinary laminin and has been shown to promote axonal regeneration in animal models of spinal cord injury. Here we used confocal fluorescence microscopy (CFM), scanning electron microscopy (SEM) and atomic force microscopy (AFM) to characterize its three-dimensional structure. Renderization of confocal optical slices of immunostained polyLM revealed the aspect of a loose flocculated meshwork, which was homogeneously stained by the antibody. On the other hand, an ordinary matrix obtained upon adsorption of laminin in neutral pH (LM) was constituted of bulky protein aggregates whose interior was not accessible to the same anti-laminin antibody. SEM and AFM analyses revealed that the seed unit of polyLM was a flat polygon formed in solution whereas the seed structure of LM was highly heterogeneous, intercalating rod-like, spherical and thin spread lamellar deposits. As polyLM was visualized at progressively increasing magnifications, we observed that the morphology of the polymer was alike independently of the magnification used for the observation. A search for the Hausdorff dimension in images of the two matrices showed that polyLM, but not LM, presented fractal dimensions of 1.55, 1.62 and 1.70 after 1, 8 and 12 hours of adsorption, respectively. Data in the present work suggest that the intrinsic fractal nature of polymerized laminin can be the structural basis for the fractal-like organization of basement membranes in the neurogenic niches of the central nervous system.This work was supported by a grant from the Brazilian National Research Council (CNPq; 476772/2008-7) to TCS. MSS acknowledges support from the European Research Council through ERC - 306990. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Hochman Méndez, C.; Cantini ., M.; Moratal Pérez, D.; Salmerón Sánchez, M.; Coelho-Sampaio, T. (2014). A fractal nature for polymerized laminin. PLoS ONE. 9(10):109388-1-109388-11. https://doi.org/10.1371/journal.pone.0109388S109388-1109388-11910Durbeej, M. (2009). Laminins. Cell and Tissue Research, 339(1), 259-268. doi:10.1007/s00441-009-0838-2Miner, J. H., & Yurchenco, P. D. (2004). LAMININ FUNCTIONS IN TISSUE MORPHOGENESIS. Annual Review of Cell and Developmental Biology, 20(1), 255-284. doi:10.1146/annurev.cellbio.20.010403.094555Yurchenco, P. D. (2010). Basement Membranes: Cell Scaffoldings and Signaling Platforms. Cold Spring Harbor Perspectives in Biology, 3(2), a004911-a004911. doi:10.1101/cshperspect.a004911Hohenester, E., & Yurchenco, P. D. (2013). 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    The KLF4 tumour suppressor is a transcriptional repressor of p53 that acts as a context-dependent oncogene

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    KLF4 (GKLF/EZF) encodes a transcription factor that is associated with both tumour suppression and oncogenesis. We describe the identification of KLF4 in a functional genomic screen for genes that bypass RASV12-induced senescence. However, in untransformed cells, KLF4 acts as a potent inhibitor of proliferation. KLF4-induced arrest is bypassed by oncogenic RASV12 or by the RAS target cyclin-D1. Remarkably, inactivation of the cyclin-D1 target and the cell-cycle inhibitor p21CIP1 not only neutralizes the cytostatic action of KLF4, but also collaborates with KLF4 in oncogenic transformation. Conversely, KLF4 suppresses the expression of p53 by directly acting on its promoter, thereby allowing for RASV12-mediated transformation and causing resistance to DNA-damage-induced apoptosis. Consistently, KLF4 depletion from breast cancer cells restores p53 levels and causes p53-dependent apoptosis. These results unmask KLF4 as a regulator of p53 that oncogenically transforms cells as a function of p21CIP1 status. Furthermore, they provide a mechanistic explanation for the context-dependent oncogenic or tumour-suppressor functions of KLF4
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