12 research outputs found
Treatment Outcomes of Multidrug-Resistant Tuberculosis: A Systematic Review and Meta-Analysis
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
Targeting PBK/TOPK decreases growth and survival of glioma initiating cells in vitro and attenuates tumor growth in vivo
A fractal nature for polymerized laminin
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). Laminins in basement membrane assembly. Cell Adhesion & Migration, 7(1), 56-63. doi:10.4161/cam.21831Freire, E., & Coelho-Sampaio, T. (2000). Self-assembly of Laminin Induced by Acidic pH. Journal of Biological Chemistry, 275(2), 817-822. doi:10.1074/jbc.275.2.817Freire, E., Sant’Ana Barroso, M. M., Klier, R. N., & Coelho-Sampaio, T. (2011). Biocompatibility and Structural Stability of a Laminin Biopolymer. Macromolecular Bioscience, 12(1), 67-74. doi:10.1002/mabi.201100125Freire, E. (2002). Structure of laminin substrate modulates cellular signaling for neuritogenesis. Journal of Cell Science, 115(24), 4867-4876. doi:10.1242/jcs.00173Hochman-Mendez, C., Lacerda de Menezes, J. R., Sholl-Franco, A., & Coelho-Sampaio, T. (2013). Polylaminin recognition by retinal cells. Journal of Neuroscience Research, 92(1), 24-34. doi:10.1002/jnr.23298Menezes, K., Ricardo Lacerda de Menezes, J., Assis Nascimento, M., de Siqueira Santos, R., & Coelho-Sampaio, T. (2010). Polylaminin, a polymeric form of laminin, promotes regeneration after spinal cord injury. The FASEB Journal, 24(11), 4513-4522. doi:10.1096/fj.10-157628Barroso, M. M. S., Freire, E., Limaverde, G. S. C. S., Rocha, G. M., Batista, E. J. O., Weissmüller, G., … Coelho-Sampaio, T. (2008). Artificial Laminin Polymers Assembled in Acidic pH Mimic Basement Membrane Organization. Journal of Biological Chemistry, 283(17), 11714-11720. doi:10.1074/jbc.m709301200Freire, E. (2004). Sialic acid residues on astrocytes regulate neuritogenesis by controlling the assembly of laminin matrices. Journal of Cell Science, 117(18), 4067-4076. doi:10.1242/jcs.01276Hausdorff, F. (1918). Dimension und �u�eres Ma�. Mathematische Annalen, 79(1-2), 157-179. doi:10.1007/bf01457179Soille, P., & Rivest, J.-F. (1996). On the Validity of Fractal Dimension Measurements in Image Analysis. Journal of Visual Communication and Image Representation, 7(3), 217-229. doi:10.1006/jvci.1996.0020Theiler, J. (1990). Estimating fractal dimension. Journal of the Optical Society of America A, 7(6), 1055. doi:10.1364/josaa.7.001055Otsu, N. (1979). A Threshold Selection Method from Gray-Level Histograms. IEEE Transactions on Systems, Man, and Cybernetics, 9(1), 62-66. doi:10.1109/tsmc.1979.4310076Iranfar, H., Rajabi, O., Salari, R., & Chamani, J. (2012). Probing the Interaction of Human Serum Albumin with Ciprofloxacin in the Presence of Silver Nanoparticles of Three Sizes: Multispectroscopic and ζ Potential Investigation. The Journal of Physical Chemistry B, 116(6), 1951-1964. doi:10.1021/jp210685qPalmero, C. Y., Miranda-Alves, L., Sant’Ana Barroso, M. M., Souza, E. C. L., Machado, D. E., Palumbo-Junior, A., … Nasciutti, L. E. (2013). The follicular thyroid cell line PCCL3 responds differently to laminin and to polylaminin, a polymer of laminin assembled in acidic pH. Molecular and Cellular Endocrinology, 376(1-2), 12-22. doi:10.1016/j.mce.2013.05.020Behrens, D. T., Villone, D., Koch, M., Brunner, G., Sorokin, L., Robenek, H., … Hansen, U. (2012). The Epidermal Basement Membrane Is a Composite of Separate Laminin- or Collagen IV-containing Networks Connected by Aggregated Perlecan, but Not by Nidogens. Journal of Biological Chemistry, 287(22), 18700-18709. doi:10.1074/jbc.m111.336073Colognato, H., Winkelmann, D. A., & Yurchenco, P. D. (1999). Laminin Polymerization Induces a Receptor–Cytoskeleton Network. The Journal of Cell Biology, 145(3), 619-631. doi:10.1083/jcb.145.3.619Liesi, P., & Silver, J. (1988). Is astrocyte laminin involved in axon guidance in the mammalian CNS? Developmental Biology, 130(2), 774-785. doi:10.1016/0012-1606(88)90366-1Zhou, F. C. (1990). Four patterns of laminin-immunoreactive structure in developing rat brain. Developmental Brain Research, 55(2), 191-201. doi:10.1016/0165-3806(90)90200-iGarcia-Abreu, J., Cavalcante, L. A., & Neto, V. M. (1995). Differential patterns of laminin expression in lateral and medial midbrain glia. NeuroReport, 6(5), 761-764. doi:10.1097/00001756-199503270-00014Kazanis, I., & ffrench-Constant, C. (2011). Extracellular matrix and the neural stem cell niche. Developmental Neurobiology, 71(11), 1006-1017. doi:10.1002/dneu.20970Mercier F, Schnack J, Chaumet MSG (2011) Chapter 4 Fractones: home and conductors of the neural stem cell niche. In: Seki, T., Sawamoto, K., Parent, J. M., Alvarez-Buylla, A., (Eds.) Neurogenesis in the adult brain I: neurobiology. Springer. pp 109–133.CAVALCANTIADAM, E., MICOULET, A., BLUMMEL, J., AUERNHEIMER, J., KESSLER, H., & SPATZ, J. (2006). Lateral spacing of integrin ligands influences cell spreading and focal adhesion assembly. European Journal of Cell Biology, 85(3-4), 219-224. doi:10.1016/j.ejcb.2005.09.011Frith, J. E., Mills, R. J., & Cooper-White, J. J. (2012). Lateral spacing of adhesion peptides influences human mesenchymal stem cell behaviour. Journal of Cell Science, 125(2), 317-327. doi:10.1242/jcs.087916Hernández, J. C. R., Salmerón Sánchez, M., Soria, J. M., Gómez Ribelles, J. L., & Monleón Pradas, M. (2007). Substrate Chemistry-Dependent Conformations of Single Laminin Molecules on Polymer Surfaces are Revealed by the Phase Signal of Atomic Force Microscopy. Biophysical Journal, 93(1), 202-207. doi:10.1529/biophysj.106.102491Douet, V., Kerever, A., Arikawa-Hirasawa, E., & Mercier, F. (2013). Fractone-heparan sulphates mediate FGF-2 stimulation of cell proliferation in the adult subventricular zone. Cell Proliferation, 46(2), 137-145. doi:10.1111/cpr.12023Nikolova, G., Strilic, B., & Lammert, E. (2007). The vascular niche and its basement membrane. Trends in Cell Biology, 17(1), 19-25. doi:10.1016/j.tcb.2006.11.005Yurchenco, P. D., Amenta, P. S., & Patton, B. L. (2004). Basement membrane assembly, stability and activities observed through a developmental lens. Matrix Biology, 22(7), 521-538. doi:10.1016/j.matbio.2003.10.006Nikolova, G., Jabs, N., Konstantinova, I., Domogatskaya, A., Tryggvason, K., Sorokin, L., … Lammert, E. (2006). The Vascular Basement Membrane: A Niche for Insulin Gene Expression and β Cell Proliferation. Developmental Cell, 10(3), 397-405. doi:10.1016/j.devcel.2006.01.015Qu, H., Liu, X., Ni, Y., Jiang, Y., Feng, X., Xiao, J., … Zheng, C. (2014). Laminin 411 acts as a potent inducer of umbilical cord mesenchymal stem cell differentiation into insulin-producing cells. Journal of Translational Medicine, 12(1), 135. doi:10.1186/1479-5876-12-135Kanatsu-Shinohara, M., & Shinohara, T. (2013). Spermatogonial Stem Cell Self-Renewal and Development. Annual Review of Cell and Developmental Biology, 29(1), 163-187. doi:10.1146/annurev-cellbio-101512-122353Lander, A. D., Kimble, J., Clevers, H., Fuchs, E., Montarras, D., Buckingham, M., … Oskarsson, T. (2012). What does the concept of the stem cell niche really mean today? BMC Biology, 10(1). doi:10.1186/1741-7007-10-19Loulier, K., Lathia, J. D., Marthiens, V., Relucio, J., Mughal, M. R., Tang, S.-C., … ffrench-Constant, C. (2009). β1 Integrin Maintains Integrity of the Embryonic Neocortical Stem Cell Niche. PLoS Biology, 7(8), e1000176. doi:10.1371/journal.pbio.100017
The KLF4 tumour suppressor is a transcriptional repressor of p53 that acts as a context-dependent oncogene
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