Processo de produção de endostatina dimerizada ou oligomerizada, endostatina dimerizada ou oligomerizada e composição farmacêutica

Anuidade de pedido de patente de invenção no prazo ordinárioDepositadaA presente invenção está relacionada à preparação de endostatina para o tratamento de câncer pela sua capacidade de regredir formação de vasos sanguíneos de um tumor pré-estabelecido. Mais especificamente, a presente invenção está relacionada à preparação de endostatina naturalmente dimerizada ou oligomérica, formada pela associação não covalente entre subunidades da proteína, apresentada na forma solúvel e sendo de fácil aplicação clinica

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. 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Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Antiangiogenic Factor Endostatin Studied by Molecular Dynamics

Tumor growth depends on its capacity to induce formation of new blood vessels [1]. Endostatin, a 20-kDa C-terminal fragment of collagen XVIII, is a potent antiangiogenic agent, fully inhibiting tumor growth in mouse models [2]. Since 2000, endostatin has been tested in patients as an experimental therapeutic agent. Results of clinical trials show that tumor size is not reduced under endostatin administration in the majority of patients. Only in one patient, who received a 20-fold higher dose, there was some response

Polymerized Laminin-521: A Feasible Substrate for Expanding Induced Pluripotent Stem Cells at a Low Protein Concentration

Laminins (LNs) play a central role in the self-assembly and maintenance of basement membranes and are involved in critical interactions between cells and other extracellular matrix (ECM) proteins. Among the defined, xeno-free ECM culture matrices, LNs&mdash;namely LN521&mdash;have emerged as promising coating systems for the large-scale expansion of induced pluripotent stem cells (iPSCs). The biologic activity of LNs is enhanced by their acidification-induced self-polymerization into a cell-associated network called polylaminin (polyLN), which can recapitulate the native-like polymeric array in a cell-free system. Here, we show for the first time to our knowledge that polyLN521 displays a native-like hexagonal-like structure and that, at basal and low concentrations, it permits the large-scale expansion of human iPSCs. Human iPSCs expanded with polyLN521 maintained the pluripotent state and showed no impairment of karyotype stability or telomere length. These results suggest that low-concentration polyLN521 is a stable and cost-effective coating for large-scale iPSC expansion