RESUMO
In view of its heterogeneity, schizophrenia needs new diagnostic tools based on mechanistic biomarkers that would allow early detection. Complex interaction between genetic and environmental risk factors may lead to NMDAR hypofunction, inflammation and redox dysregulation, all converging on oxidative stress. Using computational analysis, the expression of 76 genes linked to these systems, known to be abnormally regulated in schizophrenia, was studied in skin-fibroblasts from early psychosis patients and age-matched controls (N = 30), under additional pro-oxidant challenge to mimic environmental stress. To evaluate the contribution of a genetic risk related to redox dysregulation, we investigated the GAG trinucleotide polymorphism in the key glutathione (GSH) synthesizing enzyme, glutamate-cysteine-ligase-catalytic-subunit (gclc) gene, known to be associated with the disease. Patients and controls showed different gene expression profiles that were modulated by GAG-gclc genotypes in combination with oxidative challenge. In GAG-gclc low-risk genotype patients, a global gene expression dysregulation was observed, especially in the antioxidant system, potentially induced by other risks. Both controls and patients with GAG-gclc high-risk genotype (gclcGAG-HR) showed similar gene expression profiles. However, under oxidative challenge, a boosting of other antioxidant defense, including the master regulator Nrf2 and TRX systems was observed only in gclcGAG-HR controls, suggesting a protective compensation against the genetic GSH dysregulation. Moreover, RAGE (redox/inflammation interaction) and AGMAT (arginine pathway) were increased in the gclcGAG-HR patients, suggesting some additional risk factors interacting with this genotype. Finally, the use of a machine-learning approach allowed discriminating patients and controls with an accuracy up to 100%, paving the way towards early detection of schizophrenia.
Assuntos
Antioxidantes , Transtornos Psicóticos , Humanos , Transcriptoma , Transtornos Psicóticos/genética , Transtornos Psicóticos/metabolismo , Oxirredução , Glutationa/metabolismo , Estresse Oxidativo/genética , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Fibroblastos , Inflamação/metabolismoRESUMO
BACKGROUND: In contrast to modern rational metabolic engineering, classical strain development strongly relies on random mutagenesis and screening for the desired production phenotype. Nowadays, with the availability of biosensor-based FACS screening strategies, these random approaches are coming back into fashion. In this study, we employ this technology in combination with comparative genome analyses to identify novel mutations contributing to product formation in the genome of a Corynebacterium glutamicum L-histidine producer. Since all known genetic targets contributing to L-histidine production have been already rationally engineered in this strain, identification of novel beneficial mutations can be regarded as challenging, as they might not be intuitively linkable to L-histidine biosynthesis. RESULTS: In order to identify 100 improved strain variants that had each arisen independently, we performed > 600 chemical mutagenesis experiments, > 200 biosensor-based FACS screenings, isolated > 50,000 variants with increased fluorescence, and characterized > 4500 variants with regard to biomass formation and L-histidine production. Based on comparative genome analyses of these 100 variants accumulating 10-80% more L-histidine, we discovered several beneficial mutations. Combination of selected genetic modifications allowed for the construction of a strain variant characterized by a doubled L-histidine titer (29 mM) and product yield (0.13 C-mol C-mol-1) in comparison to the starting variant. CONCLUSIONS: This study may serve as a blueprint for the identification of novel beneficial mutations in microbial producers in a more systematic manner. This way, also previously unexplored genes or genes with previously unknown contribution to the respective production phenotype can be identified. We believe that this technology has a great potential to push industrial production strains towards maximum performance.
Assuntos
Bactérias , Histidina , Edição de Genes , Mutagênese , MutaçãoRESUMO
The period of study and/or vocational training coincides with the phase of life where a large proportion of psychiatric disorders emerge. It is therefore common to be asked by a young person in training to make adjustments to his or her training for psychological reasons. Some disorders that were thought to occur in childhood also exist in adults: this is the case of attention deficit disorder with or without hyperactivity, which must be detected and treated appropriately. The tools available for the treatment of psychiatric disorders are not limited to medication and the usefulness of psychotherapy or physical approaches, for example, is well known. We are less aware of the beneficial effects of exposure to nature and green spaces, which are however solidly supported by scientific studies - and which we should not underestimate.
La période des études et/ou de la formation professionnelle est une phase de vie au cours de laquelle émergent une grande partie des troubles psychiques. Il n'est donc pas rare d'être sollicité par un jeune en formation au sujet d'un aménagement de la formation pour des raisons psychiques. Certains des troubles qu'on pensait survenir dans l'enfance existent aussi chez l'adulte. C'est le cas du trouble de déficit de l'attention avec ou sans hyperactivité. Les outils à disposition pour le traitement des troubles psychiques ne se restreignent pas aux médicaments : on connaît l'utilité des psychothérapies ou des approches corporelles par exemple. On connaît moins les effets bénéfiques de l'exposition à la nature et aux espaces verts, qui sont pourtant solidement étayés par des études scientifiques et que l'on aurait tort de sous-estimer.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Psiquiatria , Humanos , Masculino , Adulto , Feminino , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , PsicoterapiaRESUMO
BACKGROUND: Cardiovascular impairment contributes to increased mortality in preterm infants with chronic lung disease. Macitentan, an endothelin-1 receptor antagonist, has the potential to attenuate pulmonary and cardiovascular remodelling. METHODS: In a prospective randomized placebo-controlled intervention trial, Sprague-Dawley rats were exposed to 0.21 or 1.0 fraction of inspired oxygen (FiO2) for 19 postnatal days. Rats were treated via gavage with placebo or macitentan from days of life 5 to 19. Alveoli, pulmonary vessels, α-smooth muscle actin content in pulmonary arterioles, size of cardiomyocytes, right to left ventricular wall diameter ratio, and endothelin-1 plasma concentrations were assessed. RESULTS: FiO2 1.0 induced typical features of chronic lung disease with significant alveolar enlargement (p = 0.012), alveolar (p = 0.048) and pulmonary vessel rarefaction (p = 0.024), higher α-smooth muscle actin content in pulmonary arterioles (p = 0.009), higher right to left ventricular wall diameter ratio (p = 0.02), and larger cardiomyocyte cross-sectional area (p < 0.001). Macitentan treatment significantly increased pulmonary vessel count (p = 0.004) and decreased right to left ventricular wall diameter ratios (p = 0.002). Endothelin-1 plasma concentrations were higher compared to placebo (p = 0.015). Alveolar number and size, α-smooth muscle actin, and the cardiomyocyte cross-sectional area remained unchanged (all p > 0.05). CONCLUSION: The endothelin-1 receptor antagonist macitentan attenuated cardiovascular remodelling in an infant rat model for preterm chronic lung disease. This study underscores the potential of macitentan to reduce cardiovascular morbidity in preterm infants with chronic lung disease.
Assuntos
Hipertensão Pulmonar , Animais , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Miócitos Cardíacos , Estudos Prospectivos , Pirimidinas , Ratos , Ratos Sprague-Dawley , SulfonamidasRESUMO
Early intervention in psychosis is crucial to improving patient response to treatment and the functional deficits that critically affect their long-term quality of life. Stratification tools are needed to personalize functional deficit prevention strategies at an early stage. In the present study, we applied topological tools to analyze symptoms of early psychosis patients, and detected a clear stratification of the cohort into three groups. One of the groups had a significantly better psychosocial outcome than the others after a 3-year clinical follow-up. This group was characterized by a metabolic profile indicative of an activated antioxidant response, while that of the groups with poorer outcome was indicative of oxidative stress. We replicated in a second cohort the finding that the three distinct clinical profiles at baseline were associated with distinct outcomes at follow-up, thus validating the predictive value of this new stratification. This approach could assist in personalizing treatment strategies.
Assuntos
Transtornos Psicóticos , Qualidade de Vida , HumanosRESUMO
Rats are often used in ventilator-induced lung injury (VILI) models. However, strain-specific susceptibility for VILI has not been elucidated yet. The aim of this study was to demonstrate strain-specific differences in VILI in infant Sprague-Dawley and Wistar rats. VILI was compared in 2-wk-old pups after 8 h of protective or injurious ventilation. Pups were ventilated with tidal volumes (VT) of â¼7 mL/kg and positive end-expiratory pressures (PEEP) of 6 cmH2O (VT7 PEEP6) or with VT of â¼21 mL/kg and PEEP 2 cmH2O (VT21 PEEP2). Interleukin-6, macrophage inflammatory protein-2 (MIP-2), inflammatory cells, and albumin in bronchoalveolar lavage fluid (BALF); histology; and low-frequency forced oscillation technique (LFOT) and pressure-volume (PV) maneuvers were assessed. Alveolar macrophages, neutrophils, and MIP-2 derived from BALF revealed more pronounced VILI after VT21 PEEP2 in both strains. LFOT and PV analyses demonstrated rat strain-specific differences both at baseline and particularly in response to VT21 PEEP2 ventilation. Sprague-Dawley rats showed higher airway and tissue resistance and elastance values with no difference in hysteresivity between ventilation strategies. Wister rats challenged by VT21 PEEP2 experienced significantly more energy dissipation when compared with VT7 PEEP6 ventilation. In conclusion, both rat strains are useful for VILI models. The degree of VILI severity depends on ventilation strategy and selected strain. However, fundamental and time-dependent differences in respiratory system mechanics exist and reflect different lung tissue viscoelasticity. Hence, strain-specific characteristics of the respiratory system need to be considered when planning and interpreting VILI studies with infant rats.
Assuntos
Líquido da Lavagem Broncoalveolar/química , Macrófagos Alveolares/patologia , Mecânica Respiratória , Lesão Pulmonar Induzida por Ventilação Mecânica/fisiopatologia , Animais , Animais Recém-Nascidos , Elasticidade , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Lesão Pulmonar Induzida por Ventilação Mecânica/classificação , ViscosidadeRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
Various mechanisms involved in schizophrenia pathophysiology, such as dopamine dysregulation, glutamate/NMDA receptor dysfunction, neuroinflammation or redox imbalance, all appear to converge towards an oxidative stress "hub" affecting parvalbumine interneurones (PVI) and their perineuronal nets (PNN) (Lancet Psychiatry. 2015;2:258-70); (Nat Rev Neurosci. 2016;17:125-34). We aim to investigate underlying mechanisms linking oxidative stress with neuroinflammatory and their long-lasting harmful consequences. In a transgenic mouse of redox dysregulation carrying a permanent deficit of glutathione synthesis (gclm-/-), the anterior cingulate cortex presented early in the development increased oxidative stress which was prevented by the antioxidant N-acetylcysteine (Eur J Neurosci. 2000;12:3721-8). This oxidative stress induced microglia activation and redox-sensitive matrix metalloproteinase 9 (MMP9) stimulation, leading to the receptor for advanced glycation end-products (RAGE) shedding into soluble and nuclear forms, and subsequently to nuclear factor-kB (NF-kB) activation and secretion of various cytokines. Blocking MMP9 activation prevented this sequence of alterations and rescued the normal maturation of PVI/PNN, even if performed after an additional insult that exacerbated the long term PVI/PNN impairments. MMP9 inhibition thus appears to be able to interrupt the vicious circle that maintains the long-lasting deleterious effects of the reciprocal interaction between oxidative stress and neuroinflammation, impacting on PVI/PNN integrity. Translation of these experimental findings to first episode patients revealed an increase in plasma soluble RAGE relative to healthy controls. This increase was associated with low prefrontal GABA levels, potentially predicting a central inhibitory/excitatory imbalance linked to RAGE shedding. This study paves the way for mechanistically related biomarkers needed for early intervention and MMP9/RAGE pathway modulation may lead to promising drug targets.
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Inflamação/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neuroimunomodulação , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Esquizofrenia/metabolismo , Adulto , Animais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Oxirredução , Estresse OxidativoRESUMO
Exposure to childhood trauma (CT) increases the risk for psychosis and affects the development of brain structures, possibly through oxidative stress. As oxidative stress is also linked to psychosis, it may interact with CT, leading to a more severe clinical phenotype. In 133 patients with early psychosis (EPP), we explored the relationships between CT and hippocampal, amygdala, and intracranial volume (ICV); blood antioxidant defenses [glutathione peroxidase (GPx) and thioredoxin/peroxiredoxin (Trx/Prx)]; psychopathological results; and neuropsychological results. Nonadjusted hippocampal volume correlated negatively with GPx activity in patients with CT, but not in patients without CT. In patients with CT with high GPx activity (high-GPx+CT), hippocampal volume was decreased compared with that in patients with low-GPx+CT and patients without CT, who had similar hippocampal volumes. Patients with high-GPx+CT had more severe positive and disorganized symptoms than other patients. Interestingly, Trx and oxidized Prx levels correlated negatively with GPx only in patients with low-GPx+CT. Moreover, patients with low-GPx+CT performed better than other patients on cognitive tasks. Discriminant analysis combining redox markers, hippocampal volume, clinical scores, and cognitive scores allowed for stratification of the patients into subgroups. In conclusion, traumatized EPP with high peripheral oxidation status (high-GPx activity) had smaller hippocampal volumes and more severe symptoms, while those with lower oxidation status (low-GPx activity) showed better cognition and regulation of GPx and Trx/Prx systems. These results suggest that maintained regulation of various antioxidant systems allowed for compensatory mechanisms preventing long-term neuroanatomical and clinical impacts. The redox marker profile may thus represent important biomarkers for defining treatment strategies in patients with psychosis.
Assuntos
Estresse Oxidativo , Transtornos Psicóticos/etiologia , Ferimentos e Lesões/complicações , Adulto , Antioxidantes , Criança , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Masculino , Oxirredução , Peroxirredoxinas , Tiorredoxinas , Adulto JovemRESUMO
The poorly understood tolerance toward high tidal volume (VT) ventilation observed in critically ill children and age-equivalent animal models may be explained by surfactant homeostasis. The aim of our prospective animal study was to test whether high VT with adequate positive end-expiratory pressure (PEEP) is associated with surfactant de novo synthesis and secretion, leading to improved lung function, and whether extreme mechanical ventilation affects intracellular lamellar body formation and exocytosis. Rats (14 days old) were allocated to five groups: nonventilated controls, PEEP 5 cmH2O with VT of 8, 16, and 24 mL/kg, and PEEP 1 cmH2O with VT 24 mL/kg. Following 6 h of ventilation, lung function, surfactant proteins and phospholipids, and lamellar bodies were assessed by forced oscillation technique, quantitative real-time polymerase chain reaction, mass spectrometry, immunohistochemistry, and transmission electron microscopy. High VT (24 mL/kg) with PEEP of 5 cmH2O improved respiratory system mechanics and was not associated with lung injury, elevated surfactant protein expression, or surfactant phospholipid content. Extreme ventilation with VT 24 mL/kg and PEEP 1 cmH2O produced a mild inflammatory response and correlated with higher surfactant phospholipid concentrations in bronchoalveolar lavage fluid without affecting lamellar body count and morphology. Elevated phospholipid concentrations in the potentially most injurious strategy (VT 24 mL/kg, PEEP 1 cmH2O) need further evaluation and might reflect accumulation of biophysically inactive small aggregates. In conclusion, our data confirm the resilience of infant rats toward high VT-induced lung injury and challenge the relevance of surfactant synthesis, storage, and secretion as protective factors.
Assuntos
Lesão Pulmonar/metabolismo , Lesão Pulmonar/fisiopatologia , Surfactantes Pulmonares/metabolismo , Volume de Ventilação Pulmonar/fisiologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Pulmão/metabolismo , Pulmão/fisiopatologia , Ratos , Mecânica Respiratória/fisiologia , Tensoativos/metabolismoRESUMO
The structural complexity of the thalamus, due to its mixed composition of gray and white matter, make it challenging to disjoint and quantify each tissue contribution to the thalamic anatomy. This work promotes the use of partial-volume-based over probabilistic-based tissue segmentation approaches to better capture thalamic gray matter differences between patients at different stages of psychosis (early and chronic) and healthy controls. The study was performed on a cohort of 23 patients with schizophrenia, 41 with early psychosis and 69 age and sex-matched healthy subjects. Six tissue segmentation approaches were employed to obtain the gray matter concentration/probability images. The statistical tests were applied at three different anatomical scales: whole thalamus, thalamic subregions and voxel-wise. The results suggest that the partial volume model estimation of gray matter is more sensitive to detect atrophies within the thalamus of patients with psychosis. However all the methods detected gray matter deficit in the pulvinar, particularly in early stages of psychosis. This study demonstrates also that the gray matter decrease varies nonlinearly with age and between nuclei. While a gray matter loss was found in the pulvinar of patients in both stages of psychosis, reduced gray matter in the mediodorsal was only observed in early psychosis subjects. Finally, our analyses point to alterations in a sub-region comprising the lateral posterior and ventral posterior nuclei. The obtained results reinforce the hypothesis that thalamic gray matter assessment is more reliable when the tissues segmentation method takes into account the partial volume effect.
Assuntos
Substância Cinzenta/patologia , Interpretação de Imagem Assistida por Computador/métodos , Neuroimagem/métodos , Transtornos Psicóticos/patologia , Esquizofrenia/patologia , Núcleos Talâmicos/patologia , Adulto , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Transtornos Psicóticos/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Núcleos Talâmicos/diagnóstico por imagem , Fatores de Tempo , Adulto JovemRESUMO
PURPOSE: Urban living is a major risk factor for psychosis. Considering worldwide increasing rates of urbanization, new approaches are needed to enhance patients' wellbeing in cities. Recent data suggest that once psychosis has emerged, patients struggle to adapt to urban milieu and that they lose access to city centers, which contributes to isolation and reduced social contacts. While it is acknowledged that there are promising initiatives to improve mental health in cities, concrete therapeutic strategies to help patients with psychosis to better handle urban stress are lacking. We believe that we should no longer wait to develop and test new therapeutic approaches. METHOD: In this review, we first focus on the role of urban planning, policies, and design, and second on possible novel therapeutic strategies at the individual level. We review how patients with psychosis may experience stress in the urban environment. We then review and describe a set of possible strategies, which could be proposed to patients with the first-episode psychosis. RESULTS: We propose to group these strategies under the umbrella term of 'urban remediation' and discuss how this novel approach could help patients to recover from their first psychotic episode. CONCLUSION: The concepts developed in this paper are speculative and a lot of work remains to be done before it can be usefully proposed to patients. However, considering the high prevalence of social withdrawal and its detrimental impact on the recovery process, we strongly believe that researchers should invest this new domain to help patients regain access to city centers.
Assuntos
Saúde Mental , Transtornos Psicóticos , Estresse Psicológico , Urbanização , Adulto , Cidades , Feminino , Humanos , Masculino , Transtornos Psicóticos/psicologia , Fatores de RiscoRESUMO
Living in an urban environment increases the risk to develop psychosis. An interdisciplinary research project has allowed a better definition of urban stress components and the adaptation strategies applied by patients to face it. On this basis, the concept of « urban remediation ¼ has emerged as a strategy to help patients regain access to the city. Among the other new treatment approaches, we also discuss therapy through games, which, due to their flexibility and variety, can suit many different needs. These approaches allow the reinforcement of coping capacities through diverse strategies, ranging from the promotion of social interactions to cognitive restructuration or behavioral activation. In addition, the engaging nature of these games may facilitate access and adherence to treatment.
Vivre en milieu urbain augmente le risque de développer un trouble psychotique. Une recherche interdisciplinaire a permis d'identifier plus précisément les éléments qui composent le stress urbain et les stratégies des patients pour s'y adapter, et de développer la remédiation urbaine, stratégie thérapeutique visant à faciliter la reconquête de l'espace urbain. Les thérapies par le jeu, qui, du fait de leur flexibilité, peuvent quant à elles s'adapter à toutes sortes de besoins, et permettent de renforcer les stratégies d'adaptation des patients, en s'appuyant sur des stratégies de changements variées, allant du renforcement des interactions sociales à la restructuration cognitive ou à l'activation comportementale. De plus, l'attractivité des jeux pourrait faciliter l'entrée ou le maintien dans les soins.
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Psiquiatria , Transtornos Psicóticos , Adaptação Psicológica , Humanos , Relações Interpessoais , Psiquiatria/tendênciasRESUMO
BACKGROUND: Hyperoxia-induced bronchopulmonary dysplasia (BPD) models are essential for better understanding and impacting on long-term pulmonary, cardiovascular, and neurological sequelae of this chronic disease. Only few experimental studies have systematically compared structural alterations with lung function measurements. METHODS: In three separate and consecutive series, Sprague-Dawley infant rats were exposed from day of life (DOL) 1 to 19 to either room air (0.21; controls) or to fractions of inspired oxygen (FiO2) of 0.6, 0.8, and 1.0. Our primary outcome parameters were histopathologic analyses of heart, lungs, and respiratory system mechanics, assessed via image analysis tools and the forced oscillation technique, respectively. RESULTS: Exposure to FiO2 of 0.8 and 1.0 resulted in significantly lower body weights and elevated coefficients of lung tissue damping (G) and elastance (H) when compared with controls. Hysteresivity (η) was lower due to a more pronounced increase of H when compared with G. A positive structure-function relation was demonstrated between H and the lung parenchymal content of α-smooth muscle actin (α-SMA) under hyperoxic conditions. Moreover, histology and morphometric analyses revealed alveolar simplification, fewer pulmonary arterioles, increased α-SMA content in pulmonary vessels, and right heart hypertrophy following hyperoxia. Also, in comparison to controls, hyperoxia resulted in significantly lower plasma levels of vascular endothelial growth factor (VEGF). Lastly, rats in hyperoxia showed hyperactive and a more explorative behaviour. CONCLUSIONS: Our in vivo infant rat model mimics clinical key features of BPD. To the best of our knowledge, this is the first BPD rat model demonstrating an association between lung structure and function. Moreover, we provide additional evidence that infant rats subjected to hyperoxia develop rarefaction of pulmonary vessels, augmented vascular α-SMA, and adaptive cardiac hypertrophy. Thus, our model provides a clinically relevant tool to further investigate diseases related to O2 toxicity and to evaluate novel pharmacological treatment strategies.
Assuntos
Cardiomegalia/etiologia , Cardiomegalia/fisiopatologia , Hiperóxia/complicações , Hiperóxia/fisiopatologia , Pulmão/patologia , Pulmão/fisiopatologia , Rarefação Microvascular/etiologia , Rarefação Microvascular/fisiopatologia , Animais , Animais Recém-Nascidos , Comportamento Animal , Biomarcadores/metabolismo , Cardiomegalia/sangue , Endotelina-1/sangue , Feminino , Humanos , Hiperóxia/sangue , Pulmão/irrigação sanguínea , Rarefação Microvascular/sangue , Miocárdio/patologia , Ratos Sprague-Dawley , Mecânica Respiratória , Comportamento Social , Análise de Sobrevida , Fator A de Crescimento do Endotélio Vascular/sangue , Aumento de PesoRESUMO
Gasification is a suitable technology to generate energy-rich synthesis gas (syngas) from biomass or waste streams, which can be utilized in bacterial fermentation processes for the production of chemicals and fuels. Established microbial processes currently rely on acetogenic bacteria which perform an energetically inefficient anaerobic CO oxidation and acetogenesis potentially hampering the biosynthesis of complex and ATP-intensive products. Since aerobic oxidation of CO is energetically more favorable, we exploit in this study the Gram-negative ß-proteobacterium Hydrogenophaga pseudoflava DSM1084 as novel host for the production of chemicals from syngas. We sequenced and annotated the genome of H. pseudoflava and established a genetic engineering toolbox, which allows markerless chromosomal modification via the pk19mobsacB system and heterologous gene expression on pBBRMCS2-based plasmids. The toolbox was extended by identifying strong endogenous promotors such as PgapA2 which proved to yield high expression under heterotrophic and autotrophic conditions. H. pseudoflava showed relatively fast heterotrophic growth in complex and minimal medium with sugars and organic acids which allows convenient handling in lab routines. In autotrophic bioreactor cultivations with syngas, H. pseudoflava exhibited a growth rate of 0.06 h-1 and biomass specific uptakes rates of 14.2⯱â¯0.3â¯mmol H2 gCDW-1 h-1, 73.9⯱â¯1.8â¯mmol CO gCDW-1 h-1, and 31.4⯱â¯0.3â¯mmol O2 gCDW-1 h-1. As proof of concept, we engineered the carboxydotrophic bacterium for the aerobic production of the C15 sesquiterpene (E)-α-bisabolene from the C1 carbon source syngas by heterologous expression of the (E)-α-bisabolene synthase gene agBIS. The resulting strain H. pseudoflava (pOCEx1:agBIS) produced 59⯱â¯8⯵g (E)-α-bisabolene L-1 with a volumetric productivity Qp of 1.2⯱â¯0.2⯵gâ¯L-1 h-1 and a biomass-specific productivity qp of 13.1⯱â¯0.6⯵g gCDW-1 h-1. The intrinsic properties and the genetic repertoire of H. pseudoflava make this carboxydotrophic bacterium a promising candidate for future aerobic production processes to synthesize more complex or ATP-intensive chemicals from syngas.
Assuntos
Reatores Biológicos , Monóxido de Carbono/metabolismo , Comamonadaceae , Genoma Bacteriano , Microrganismos Geneticamente Modificados , Sesquiterpenos Monocíclicos/metabolismo , Aerobiose , Biomassa , Comamonadaceae/genética , Comamonadaceae/crescimento & desenvolvimento , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/crescimento & desenvolvimento , OxirreduçãoRESUMO
BACKGROUND: There is increasing evidence that redox dysregulation, which can lead to oxidative stress and eventually to impairment of oligodendrocytes and parvalbumin interneurons, may underlie brain connectivity alterations in schizophrenia. Accordingly, we previously reported that levels of brain antioxidant glutathione in the medial prefrontal cortex were positively correlated with increased functional connectivity along the cingulum bundle in healthy controls but not in early psychosis patients. In a recent randomized controlled trial, we observed that 6-month supplementation with a glutathione precursor, N-acetyl-cysteine, increased brain glutathione levels and improved symptomatic expression and processing speed. METHODS: We investigated the effect of N-acetyl-cysteine supplementation on the functional connectivity between regions of the cingulate cortex, which have been linked to positive symptoms and processing speed decline. In this pilot study, we compared structural connectivity and resting-state functional connectivity between early psychosis patients treated with 6-month N-acetyl-cysteine (n = 9) or placebo (n = 11) supplementation with sex- and age-matched healthy control subjects (n = 74). RESULTS: We observed that 6-month N-acetyl-cysteine supplementation increases functional connectivity along the cingulum and more precisely between the caudal anterior part and the isthmus of the cingulate cortex. These functional changes can be partially explained by an increase of centrality of these regions in the functional brain network. CONCLUSIONS: N-acetyl-cysteine supplementation has a positive effect on functional connectivity within the cingulate cortex in early psychosis patients. To our knowledge, this is the first study suggesting that increased brain glutathione levels via N-acetyl-cysteine supplementation may improve brain functional connectivity.
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Acetilcisteína/uso terapêutico , Antioxidantes/uso terapêutico , Suplementos Nutricionais , Giro do Cíngulo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transtornos Psicóticos/tratamento farmacológico , Acetilcisteína/efeitos adversos , Adulto , Antioxidantes/efeitos adversos , Mapeamento Encefálico/métodos , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Europa (Continente) , Feminino , Glutationa/metabolismo , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/metabolismo , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Projetos Piloto , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/metabolismo , Transtornos Psicóticos/psicologia , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Schizophrenia is a complex psychiatric disorder characterized by disabling symptoms and cognitive deficit. Recent neuroimaging findings suggest that large parts of the brain are affected by the disease, and that the capacity of functional integration between brain areas is decreased. In this study we questioned (i) which brain areas underlie the loss of network integration properties observed in the pathology, (ii) what is the topological role of the affected regions within the overall brain network and how this topological status might be altered in patients, and (iii) how white matter properties of tracts connecting affected regions may be disrupted. We acquired diffusion spectrum imaging (a technique sensitive to fiber crossing and slow diffusion compartment) data from 16 schizophrenia patients and 15 healthy controls, and investigated their weighted brain networks. The global connectivity analysis confirmed that patients present disrupted integration and segregation properties. The nodal analysis allowed identifying a distributed set of brain nodes affected in the pathology, including hubs and peripheral areas. To characterize the topological role of this affected core, we investigated the brain network shortest paths layout, and quantified the network damage after targeted attack toward the affected core. The centrality of the affected core was compromised in patients. Moreover the connectivity strength within the affected core, quantified with generalized fractional anisotropy and apparent diffusion coefficient, was altered in patients. Taken together, these findings suggest that the structural alterations and topological decentralization of the affected core might be major mechanisms underlying the schizophrenia dysconnectivity disorder.
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Encéfalo/patologia , Conectoma , Esquizofrenia/patologia , Substância Branca/patologia , Adulto , Anisotropia , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/patologia , Vias Neurais/patologiaRESUMO
The mammalian target of rapamycin plays an important role in multiple myeloma. The allosteric mammalian target of rapamycin inhibitor everolimus has long been approved for immunosuppression and has shown activity in certain cancers. This investigator-initiated phase I trial explored the use of everolimus in relapsed and/or refractory multiple myeloma patients who had received two or more lines of prior treatment. Following a dose-escalation design, it called for a fixed dose of oral everolimus. Blood drug levels were monitored and the biological activity of everolimus was evaluated in bone marrow. Seventeen patients were enrolled (age range, 52 to 76 years). All had been previously treated with stem cell transplantation and proteasome inhibitors and almost all with immunomodulatory drugs. No dose-limiting toxicity was observed and the intended final daily dose of 10 mg was reached. Only one severe adverse event was assessed as possibly related to the study drug, namely atypical pneumonia. Remarkably few infections were observed. Although the trial was mainly designed to evaluate feasibility, anti-myeloma activity, defined as clinical benefit, was documented in ten of 15 evaluable patients at every dose level including eight patients with stable disease, one patient with minor remission and one with partial remission. However, the median time to progression was 90 days (range, 13 to 278 days). The biomarker study documented on-target activity of everolimus in malignant plasma cells as well as the microenvironment. The observed responses are promising and allow further studies to be considered, including those testing combination strategies addressing escape pathways. This trial is registered with EudraCT number 2006-002675-41.
Assuntos
Antineoplásicos/uso terapêutico , Imunossupressores/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Sirolimo/análogos & derivados , Idoso , Antineoplásicos/farmacologia , Biomarcadores , Biópsia , Medula Óssea/patologia , Everolimo , Feminino , Humanos , Imunomodulação/efeitos dos fármacos , Imunossupressores/farmacologia , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Mieloma Múltiplo/imunologia , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Resultado do TratamentoRESUMO
INTRODUCTION: Sepsis is still a leading cause of morbidity and mortality, even in modern times, and thrombocytopenia has been closely associated with unfavorable disease outcome. Decreases in mitochondrial membrane potential (depolarization) were found in different tissues during sepsis. Previous work suggests that mitochondrial dysfunction of platelets correlates with clinical disease activity in sepsis. However, platelet mitochondrial membrane potential (Mmp) has not been investigated in a clinical follow-up design and not with regard to disease outcome. METHODS: In this study, platelet mitochondrial membrane depolarization was assessed by means of a fluorescent Mmp-Index with flow cytometry in 26 patients with sepsis compared with control patients. Platelet Mmp-Index on admission was correlated with the clinical disease scores Acute Physiology and Chronic Health Evaluation Score II (APACHE II), Sequential Organ Failure Score (SOFA), and Simplified Acute Physiology Score II (SAPS II). Finally, platelet Mmp-Index on admission and follow-up were compared in the group of sepsis survivors and nonsurvivors. Expression of the prosurvival protein Bcl-xL in platelets was quantified by immunoblotting. RESULTS: Platelet mitochondrial membrane depolarization correlated significantly with the simultaneously assessed clinical disease severity by APACHE II (r = -0.867; P < 0.0001), SOFA (r = -0.857; P <0.0001), and SAPS II score (r = -0.839; P < 0.0001). Patients with severe sepsis showed a significant reduction in platelet Mmp-Index compared with sepsis without organ failure (0.18 (0.12 to 0.25) versus 0.79 (0.49 to 0.85), P < 0.0006) or with the control group (0.18 (0.12 to 0.25) versus 0.89 (0.68 to 1.00), P < 0.0001). Platelet Mmp-Index remained persistently low in sepsis nonsurvivors (0.269 (0.230 to 0.305)), whereas we observed recovery of platelet Mmp-Index in the survivor group (0.9 (0.713 to 1.017)). Furthermore, the level of prosurvival protein Bcl-xL decreased in platelets during severe sepsis. CONCLUSION: In this study, we demonstrated that mitochondrial membrane depolarization in platelets correlates with clinical disease severity in patients with sepsis during the disease course and may be a valuable adjunct parameter to aid in the assessment of disease severity, risk stratification, and clinical outcome.
Assuntos
Plaquetas/fisiologia , Potencial da Membrana Mitocondrial/fisiologia , Sepse/classificação , APACHE , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Citometria de Fluxo/métodos , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/mortalidade , Prognóstico , Sepse/mortalidade , Índice de Gravidade de DoençaRESUMO
The widespread presence of micro(nano)plastics (MNPs) in the environment threatens ecosystem integrity, and thus, it is necessary to determine and assess the occurrence, characteristics, and transport of MNPs between ecological components. However, most analytical approaches are cost- and time-inefficient in providing quantitative information with sufficient detail, and interpreting results can be difficult. Alternative analyses integrating novel measurements by imaging or proximal sensing with signal processing and machine learning may supplement these approaches. In this review, we examined published research on methods used for the automated data interpretation of MNPs found in the environment or those artificially prepared by fragmenting bulk plastics. We critically reviewed the primary areas of the integrated analytical process, which include sampling, data acquisition, processing, and modeling, applied in identifying, classifying, and quantifying MNPs in soil, sediment, water, and biological samples. We also provide a comprehensive discussion regarding model uncertainties related to estimating MNPs in the environment. In the future, the development of routinely applicable and efficient methods is expected to significantly contribute to the successful establishment of automated MNP monitoring systems.