Inflação, Crescimento e Desenvolvimento: como a macroeconomia neoclássica impede o desenvolvimento

O uso de políticas ortodoxas anti-inflacionárias tem impedido a adoção tanto de estratégias de crescimento como de desenvolvimento. Constitui a base teórica neoclássica com objetivo de afastar o Estado da administração do movimento do capital não permitindo a realização de políticas fiscal ou monetária expansionistas, bem como de políticas cambiais estratégicas. Está envolta em uma ideologia pré-keynesiana baseada no comportamento hipotético do agente racional maximizador, na teoria quantitativa da moeda, num mundo em equilíbrio walrasiano, conceitos modernizados para que “expectativas racionais” transformem o medo inflacionário em ideologia contra a intervenção públic

Crise: um problema conjuntural ou da lógica da acumulação mundial?

The idea of this text is to explore that the current financial crises is the manifestation of the exhaustion of the global capital accumulation process (globalization) established by determined standard (mundialização) created in the postwar period. The first signals of this exhaustion had appeared in the 70s. The liberalization policies imposed by the proper capital from that period in order to maintain its profits, if of one hand had allowed certain global capital-productive reorganization, of another one had opened a wide space for the fictitious valuation of the capital that now bursts in crisis.Neste texto, explora-se a ideia de que a crise financeira atual é a manifestação do esgotamento do processo de acumulação mundial de capital fundado em um determinado padrão (mundialização) no pós-guerra. Os primeiros sinais desse esgotamento apareceram nos anos 1970. As soluções liberalizantes impostas pelo próprio capital a partir de então para buscar manter sua rentabilidade, se, de um lado, permitiram certa reestruturação produtiva mundial, de outro, abriram um amplo espaço para a valorização fictícia do capital que ora irrompe em crise

Structures of fibrils formed by α-synuclein hereditary disease mutant H50Q reveal new polymorphs.

Deposits of amyloid fibrils of α-synuclein are the histological hallmarks of Parkinson's disease, dementia with Lewy bodies and multiple system atrophy, with hereditary mutations in α-synuclein linked to the first two of these conditions. Seeing the changes to the structures of amyloid fibrils bearing these mutations may help to understand these diseases. To this end, we determined the cryo-EM structures of α-synuclein fibrils containing the H50Q hereditary mutation. We find that the H50Q mutation results in two previously unobserved polymorphs of α-synuclein: narrow and wide fibrils, formed from either one or two protofilaments, respectively. These structures recapitulate conserved features of the wild-type fold but reveal new structural elements, including a previously unobserved hydrogen-bond network and surprising new protofilament arrangements. The structures of the H50Q polymorphs help to rationalize the faster aggregation kinetics, higher seeding capacity in biosensor cells and greater cytotoxicity that we observe for H50Q compared to wild-type α-synuclein

Catastrophic disassembly of actin filaments via Mical-mediated oxidation.

Actin filament assembly and disassembly are vital for cell functions. MICAL Redox enzymes are important post-translational effectors of actin that stereo-specifically oxidize actin's M44 and M47 residues to induce cellular F-actin disassembly. Here we show that Mical-oxidized (Mox) actin can undergo extremely fast (84 subunits/s) disassembly, which depends on F-actin's nucleotide-bound state. Using near-atomic resolution cryoEM reconstruction and single filament TIRF microscopy we identify two dynamic and structural states of Mox-actin. Modeling actin's D-loop region based on our 3.9 Å cryoEM reconstruction suggests that oxidation by Mical reorients the side chain of M44 and induces a new intermolecular interaction of actin residue M47 (M47-O-T351). Site-directed mutagenesis reveals that this interaction promotes Mox-actin instability. Moreover, we find that Mical oxidation of actin allows for cofilin-mediated severing even in the presence of inorganic phosphate. Thus, in conjunction with cofilin, Mical oxidation of actin promotes F-actin disassembly independent of the nucleotide-bound state

Inhibition by small-molecule ligands of formation of amyloid fibrils of an immunoglobulin light chain variable domain.

Overproduction of immunoglobulin light chains leads to systemic amyloidosis, a lethal disease characterized by the formation of amyloid fibrils in patients' tissues. Excess light chains are in equilibrium between dimers and less stable monomers which can undergo irreversible aggregation to the amyloid state. The dimers therefore must disassociate into monomers prior to forming amyloid fibrils. Here we identify ligands that inhibit amyloid formation by stabilizing the Mcg light chain variable domain dimer and shifting the equilibrium away from the amyloid-prone monomer

Crystal Structure of T7 Gene 4 Ring Helicase Indicates a Mechanism for Sequential Hydrolysis of Nucleotides

AbstractWe have determined the crystal structure of an active, hexameric fragment of the gene 4 helicase from bacteriophage T7. The structure reveals how subunit contacts stabilize the hexamer. Deviation from expected six-fold symmetry of the hexamer indicates that the structure is of an intermediate on the catalytic pathway. The structural consequences of the asymmetry suggest a “binding change” mechanism to explain how cooperative binding and hydrolysis of nucleotides are coupled to conformational changes in the ring that most likely accompany duplex unwinding. The structure of a complex with a nonhydrolyzable ATP analog provides additional evidence for this hypothesis, with only four of the six possible nucleotide binding sites being occupied in this conformation of the hexamer. This model suggests a mechanism for DNA translocation