ASL expression in ALDH1A1+ neurons in the substantia nigra metabolically contributes to neurodegenerative phenotype

Argininosuccinate lyase (ASL) is essential for the NO-dependent regulation of tyrosine hydroxylase (TH) and thus for catecholamine production. Using a conditional mouse model with loss of ASL in catecholamine neurons, we demonstrate that ASL is expressed in dopaminergic neurons in the substantia nigra pars compacta, including the ALDH1A1 + subpopulation that is pivotal for the pathogenesis of Parkinson disease (PD). Neuronal loss of ASL results in catecholamine deficiency, in accumulation and formation of tyrosine aggregates, in elevation of α-synuclein, and phenotypically in motor and cognitive deficits. NO supplementation rescues the formation of aggregates as well as the motor deficiencies. Our data point to a potential metabolic link between accumulations of tyrosine and seeding of pathological aggregates in neurons as initiators for the pathological processes involved in neurodegeneration. Hence, interventions in tyrosine metabolism via regulation of NO levels may be therapeutic beneficial for the treatment of catecholamine-related neurodegenerative disorders

Switched Complex System Analysis for Modeling, Control and diagnosis

International audienceThis paper introduces a methodology of modeling for a class of Non Linear Complex Switched Systems in interaction with their environment. The models have to be adequate either for identification or for diagnosis and control. The effectiveness of this modeling technique is illustrated by experimental results obtained on a greenhouse

Aplicabilidade das técnicas de determinação de tamanho de partículas em sistemas de tratamento de água e esgoto sanitário Applicability of particle size measurement techniques in water and wastewater treatment systems

O aprimoramento de sistemas de tratamento de água e de esgoto tem sido limitado pelo pouco conhecimento dos fenômenos ocorridos no interior das unidades e pela utilização de "parâmetros" não específicos (DBO, DQO etc.) no monitoramento e controle de processos e operações. Por outro lado, fenômenos como transferência de massa, adsorção, difusão e reações bioquímicas são todos influenciados pela distribuição de tamanho de partículas, de modo que o emprego da análise de tamanho de partículas pode auxiliar na escolha e no aprimoramento de tecnologias de tratamento e na adoção de procedimentos operacionais apropriados. Neste artigo, são apresentadas as principais técnicas de determinação de tamanho de partículas e os potenciais benefícios de sua utilização em pesquisas e no aperfeiçoamento de projetos e rotinas de operação de sistemas de tratamento de água e esgoto sanitário.<br>The improvement of water and wastewater treatment systems has been limited by the little knowledge of phenomena that take place inside the units and by the use of non-specific parameters (e.g. BOD, COD etc.) in monitoring and controlling of treatment processes and operations. On the other hand, phenomena such as mass transfer, adsorption, diffusion and biochemical reaction are all influenced by particle size distribution, in a way that the use of particle size measurement can aid in choosing and improving treatment technology and in adoption of appropriate operational procedures. In this article, the main particle size measurement techniques are presented, as well as the potential benefits of its use in research and in the improvement of design and operational routines for water and wastewater treatment systems