Paxillin facilitates timely neurite initiation on soft-substrate environments by interacting with the endocytic machinery.

Neurite initiation is the first step in neuronal development and occurs spontaneously in soft tissue environments. Although the mechanisms regulating the morphology of migratory cells on rigid substrates in cell culture are widely known, how soft environments modulate neurite initiation remains elusive. Using hydrogel cultures, pharmacologic inhibition, and genetic approaches, we reveal that paxillin-linked endocytosis and adhesion are components of a bistable switch controlling neurite initiation in a substrate modulus-dependent manner. On soft substrates, most paxillin binds to endocytic factors and facilitates vesicle invagination, elevating neuritogenic Rac1 activity and expression of genes encoding the endocytic machinery. By contrast, on rigid substrates, cells develop extensive adhesions, increase RhoA activity and sequester paxillin from the endocytic machinery, thereby delaying neurite initiation. Our results highlight paxillin as a core molecule in substrate modulus-controlled morphogenesis and define a mechanism whereby neuronal cells respond to environments exhibiting varying mechanical properties

Political and social determinants of life expectancy in less developed countries: A longitudinal study

EstE livro corrEspondE à primeira experiência didática do Grupo de trabalho desenvolvimento Urbano do conselho latinoamericano de ciências sociais (clAcso), que reúne cerca de quarenta pesquisadores de diferentes instituições da região. Esta experiência tornou-se possível, graças ao fato da proposta deste curso ter sido aprovada no âmbito da cátedra Florestan Fernandes do conselho. completamente desenvolvida através do campus virtual do clAcso, teve, por principal objetivo, estimular a reflexão sobre alguns dos principais eixos teórico-conceituais e empíricos orientadores da análise da urbanização latino-americana

The Relationship between Coenzyme Q10, Oxidative Stress, and Antioxidant Enzymes Activities and Coronary Artery Disease

A higher oxidative stress may contribute to the pathogenesis of coronary artery disease (CAD). The purpose of this study was to investigate the relationship between coenzyme Q10 concentration and lipid peroxidation, antioxidant enzymes activities and the risk of CAD. Patients who were identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery were assigned to the case group (n = 51). The control group (n = 102) comprised healthy individuals with normal blood biochemical values. The plasma coenzyme Q10, malondialdehyde (MDA) and antioxidant enzymes activities (catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx)) were measured. Subjects with CAD had significant lower plasma coenzyme Q10, CAT and GPx activities and higher MDA and SOD levels compared to those of the control group. The plasma coenzyme Q10 was positively correlated with CAT and GPx activities and negatively correlated with MDA and SOD. However, the correlations were not significant after adjusting for the potential confounders of CAD with the exception of SOD. A higher level of plasma coenzyme Q10 (≥0.52 μmol/L) was significantly associated with reducing the risk of CAD. Our results support the potential cardioprotective impact of coenzyme Q10

Syndecan-2 induces filopodia and dendritic spine formation via the neurofibromin–PKA–Ena/VASP pathway

Syndecan-2 induced filopodia before spinogenesis; therefore, filopodia formation was used here as a model to study the early downstream signaling of syndecan-2 that leads to spinogenesis. Screening using kinase inhibitors indicated that protein kinase A (PKA) is required for syndecan-2–induced filopodia formation in both human embryonic kidney cells and hippocampal neurons. Because neurofibromin, a syndecan-2–binding partner, activates the cyclic adenosine monophosphate pathway, the role of neurofibromin in syndecan-2–induced filopodia formation was investigated by deletion mutant analysis, RNA interference, and dominant-negative mutant. The results showed that neurofibromin mediates the syndecan-2 signal to PKA. Among actin-associated proteins, Enabled (Ena)/vasodilator-stimulated phosphoprotein (VASP) were predicted as PKA effectors downstream of syndecan-2, as Ena/VASP, which is activated by PKA, induces actin polymerization. Indeed, when the activities of Ena/VASP were blocked, syndecan-2 no longer induced filopodia formation. Finally, in addition to filopodia formation, neurofibromin and Ena/VASP contributed to spinogenesis. This study reveals a novel signaling pathway in which syndecan-2 activates PKA via neurofibromin and PKA consequently phosphorylates Ena/VASP, promoting filopodia and spine formation

Interfacial Properties of Polyethylene Glycol/Vinyltriethoxysilane (PEG/VTES) Copolymers and their Application to Stain Resistance

In this study, polyethylene glycol (PEG) and vinyltriethoxysilane (VTES) were used in different proportions to produce a series of PEG–VTES copolymers. The copolymer molecular structures were confirmed by FTIR spectroscopy. In addition, their surface activities were evaluated by evaluating the surface tension, contact angle, and foaming properties. The results showed that these surfactants exhibited excellent surface activities and wetting power, as well as low foaming. Consequently, the application of a series of PEG/VTES copolymers can make cotton fabrics stain resistant

Construction and prokaryotic expression of the fusion gene PRRSV GP5 and Mycobacterium bovis Hsp70

Porcine reproductive and respiratory syndrome (PRRS) is an economically important swine disease that has devastated the swine industry worldwide. Vaccination with live attenuated vaccine or inactivated vaccine is the main treatment to control PRRS. However, the disadvantages such as virulence resumption of the attenuated vaccine and low immunogenicity of the inactivated vaccine call for a more efficient and safer genetically engineered vaccine. In this study, the structural protein GP5 of the PRRS virus (PRRSV), one of the major protective antigens which stimulates a protective immune response was selected to develop a genetically engineered subunit vaccine. In order to promote the immune reaction of the host to GP5, heat shock protein 70 (Hsp70) was selected as immuno-adjuvant to enhance PRRSV GP5 immunogenicity. The Hsp70 gene was amplified by PCR from attenuated Mycobacterium bovis, and the PRRSV GP5 gene was amplified by RT-PCR from the total RNA of PRRSV SCQ strain which was isolated, identified and maintained by the Animal Biotechnological Center, Sichuan Agricultural University, China. The fusion expressing plasmid pET32-GP5-Hsp70 was constructed and expressed in Escherichia coli BL21. Ni2+-chelating resin was used to purify the His-tagged fusion protein expressed under optimized expressing conditions. The rabbit anti-GP5-Hsp70 fusion protein antibody was made, and Western blot assay verified the successful expression of the fusion protein, making it possible for further investigation whether Hsp70 could improve the immunogenicity of the PRRSV GP5 subunit vaccine, or evaluating the immunogenicity of the GP5-Hsp70 subunit vaccine.Keywords: Porcine reproductive and respiratory syndrome virus (PRRSV) GP5 gene, Mycobacterium bovis Hsp70 gene, cloning, prokaryotic expression, identification.African Journal of Biotechnology Vol. 12(30), pp. 4754-476

Effects of NaCl treatment on the antioxidant enzymes of oilseed rape (Brassica napus L.) seedlings

The effects of NaCl treatment on the activity of antioxidant enzymes in leaves of oilseed rape seedlings (Brassica napus L.) were studied. The results showed that the relative water content from leaves of oilseed rape seedlings was gradually decreased and the electronic conductivity was increased during 0 - 24 h under 200 mmol.l-1 NaCl treatments. The activity of peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) was gradually increased during 0 - 24 h under 200 mmol.l-1 NaCl stress. After 24 h, the activities of these antioxidases were maximum and subsequently decreased. Quantitative realtime PCR analysis revealed that they were salt-inducible genes and their transcript levels were gradually increased during 0 - 24 h and most abundant after 24 h treatment with 200 mmol.l-1 sodium chloride. Therefore, these results from above indicated that the expressions of POD, SOD and CAT genes were induced by NaCl; the activities of POD, SOD and CAT were increased, which enhanced the tolerance of oilseed oilseed rape plants against NaCl stress