combining First Principles with deep neural networks

JP acknowledges PhD grant SFRD/BD14610472019, This work has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no 101000733 (PROMICON).Numerous studies have reported the use of hybrid semiparametric systems that combine shallow neural networks with First Principles for bioprocess modeling. Here we revisit the general bioreactor hybrid model and introduce some deep learning techniques. Multi-layer networks with varying depths were combined with First Principles equations in the form of deep hybrid models. Deep learning techniques, namely the adaptive moment estimation method (ADAM), stochastic regularization and depth-dependent weights initialization were evaluated in a hybrid modeling context. Modified sensitivity equations are proposed for the computation of gradients in order to reduce CPU time for the training of deep hybrid models. The methods are illustrated with applications to a synthetic dataset and a pilot 50 L MUT+ Pichia pastoris process expressing a single chain antibody fragment. All in all, the results point to a systematic generalization improvement of deep hybrid models over its shallow counterpart. Moreover, the CPU cost to train the deep hybrid models is shown to be lower than for the shallow counterpart. In the pilot 50L MUT+ Pichia pastoris data set, the prediction accuracy was increased by 18.4% and the CPU decreased by 43.4%.publishersversionpublishe

PO104 placebo and nocebo responses in RLS : a meta-analysis

Objective: Our goals were to estimate the placebo and nocebo responses in restless legs syndrome (RLS). Methods: Databases were searched up to October 2015. Randomised, double-blind, placebo-controlled trials of RLS patient were included. ‘Placebo response’ was defined as the within-group change from baseline, using any scale measuring RLS severity or disability. ‘Nocebo response’ was defined as the proportion of patients experiencing adverse events in the placebo arm. Random-effects meta-analysis was used to pool data. Results: We included 5046 participants. Pooled placebo response effect size was −1.41 (95%CI:−1.56-−1.25), corresponding to −6.58 points in the International RLS Study Group Scale (IRLS). Pooled nocebo response was 45.36% (95%CI:40.47%–50.29%). The placebo and nocebo responses were greater in trials with longer duration, evaluating pharmacological interventions and idiopathic RLS, and in industry funded and unpublished studies. The placebo response was considerable smaller in objective as compared to subjective outcomes. In addition, the nocebo response increases proportionally with the placebo response, and has the same predictors. Conclusions: The magnitude of the placebo response in RLS is above the threshold of minimal clinical important difference, and the frequency of adverse events is also considerable. These results are relevant to inform the design and interpretation of future clinical trials.info:eu-repo/semantics/publishedVersio

Metal-ion zeolites obtained by chemical and mechanochemical methods as Fenton-like catalysts for health applications

One of the critical steps for the development and health applications of inorganic nanoparticles is to exhibit high efficiency without inducing toxicity. In this work, metal-ion zeolites were developed to be used as Fenton-like catalysts for health applications. ZSM-5 and BEA zeolites were modified through chemical and mechanochemical methods to obtain nanomaterials with tuned particle size and texture. Characterization data showed that the modified materials kept the crystal structure although some textural modifications occurred. Upon Mn2+loading, the catalytic behavior was evaluated by Fenton-like reaction using physiological and mild acidic conditions (37 ºC, pH=7.4 and 6.4 and 50 M H2O2), since these conditions are relevant to various pathological environments. MnBEA series showed the best results by Fenton-like reactions, revealing the great potential of metal-zeolite nanomaterials for health applications.V.I. and A.R.B. thank for the PhD grants, UI/BD/152219/2021 and SFRH/BD/141058/2018, respectively. ASM thanks FCT for the Assistant Researcher contract CEECIND/01371/2017 (Embrace Project). This work was supported by FCT (Foundation for Science and Technology, Portugal) by the projects: UIDB/00100/2020. UIDP/00100/2020 and LA/P/0056/2020, CQ/UM (UID/QUI/0686/2020), CEB (UIDB/04469/2020) and LABBELS (LA/P/0029/2020), and Instituto Politécnico de Lisboa (IPL) through Project IPL/2022/ZeoMed ISEL.info:eu-repo/semantics/publishedVersio

Pro-autophagic signal induction by bacterial pore-forming toxins

Pore-forming toxins (PFT) comprise a large, structurally heterogeneous group of bacterial protein toxins. Nucleated target cells mount complex responses which allow them to survive moderate membrane damage by PFT. Autophagy has recently been implicated in responses to various PFT, but how this process is triggered is not known, and the significance of the phenomenon is not understood. Here, we show that S. aureus α-toxin, Vibrio cholerae cytolysin, streptolysin O and E. coli haemolysin activate two pathways leading to autophagy. The first pathway is triggered via AMP-activated protein kinase (AMPK). AMPK is a major energy sensor which induces autophagy by inhibiting the target of rapamycin complex 1 (TORC1) in response to a drop of the cellular ATP/AMP-ratio, as is also observed in response to membrane perforation. The second pathway is activated by the conserved eIF2α-kinase GCN2, which causes global translational arrest and promotes autophagy in response to starvation. The latter could be accounted for by impaired amino acid transport into target cells. Notably, PKR, an eIF2α-kinase which has been implicated in autophagy induction during viral infection, was also activated upon membrane perforation, and evidence was obtained that phosphorylation of eIF2α is required for the accumulation of autophagosomes in α-toxin-treated cells. Treatment with 3-methyl-adenine inhibited autophagy and disrupted the ability of cells to recover from sublethal attack by S. aureus α-toxin. We propose that PFT induce pro-autophagic signals through membrane perforation–dependent nutrient and energy depletion, and that an important function of autophagy in this context is to maintain metabolic homoeostasis

Impact of COVID-19 Lockdown in Eating Disorders: A Multicentre Collaborative International Study

Background. The COVID-19 lockdown has had a significant impact on mental health. Patients with eating disorders (ED) have been particularly vulnerable. Aims. (1) To explore changes in eating-related symptoms and general psychopathology during lockdown in patients with an ED from various European and Asian countries; and (2) to assess differences related to diagnostic ED subtypes, age, and geography. Methods. The sample comprised 829 participants, diagnosed with an ED according to DSM-5 criteria from specialized ED units in Europe and Asia. Participants were assessed using the COVID-19 Isolation Scale (CIES). Results. Patients with binge eating disorder (BED) experienced the highest impact on weight and ED symptoms in comparison with other ED subtypes during lockdown, whereas individuals with other specified feeding and eating disorders (OFSED) had greater deterioration in general psychological functioning than subjects with other ED subtypes. Finally, Asian and younger individuals appeared to be more resilient. Conclusions. The psychopathological changes in ED patients during the COVID-19 lockdown varied by cultural context and individual variation in age and ED diagnosis. Clinical services may need to target preventive measures and adapt therapeutic approaches for the most vulnerable patients

Defining novel functions for cerebrospinal fluid in ALS pathophysiology

Despite the considerable progress made towards understanding ALS pathophysiology, several key features of ALS remain unexplained, from its aetiology to its epidemiological aspects. The glymphatic system, which has recently been recognised as a major clearance pathway for the brain, has received considerable attention in several neurological conditions, particularly Alzheimer's disease. Its significance in ALS has, however, been little addressed. This perspective article therefore aims to assess the possibility of CSF contribution in ALS by considering various lines of evidence, including the abnormal composition of ALS-CSF, its toxicity and the evidence for impaired CSF dynamics in ALS patients. We also describe a potential role for CSF circulation in determining disease spread as well as the importance of CSF dynamics in ALS neurotherapeutics. We propose that a CSF model could potentially offer additional avenues to explore currently unexplained features of ALS, ultimately leading to new treatment options for people with ALS.</p