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1.
Crit Care Med ; 52(3): e121-e131, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38156913

RESUMO

OBJECTIVES: The association between protein intake and the need for mechanical ventilation (MV) is controversial. We aimed to investigate the associations between protein intake and outcomes in ventilated critically ill patients. DESIGN: Analysis of a subset of a large international point prevalence survey of nutritional practice in ICUs. SETTING: A total of 785 international ICUs. PATIENTS: A total of 12,930 patients had been in the ICU for at least 96 hours and required MV by the fourth day after ICU admission at the latest. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We modeled associations between the adjusted hazard rate (aHR) of death in patients requiring MV and successful weaning (competing risks), and three categories of protein intake (low: < 0.8 g/kg/d, standard: 0.8-1.2 g/kg/d, high: > 1.2 g/kg/d). We compared five different hypothetical protein diets (an exclusively low protein intake, a standard protein intake given early (days 1-4) or late (days 5-11) after ICU admission, and an early or late high protein intake). There was no evidence that the level of protein intake was associated with time to weaning. However, compared with an exclusively low protein intake, a standard protein intake was associated with a lower hazard of death in MV: minimum aHR 0.60 (95% CI, 0.45-0.80). With an early high intake, there was a trend to a higher risk of death in patients requiring MV: maximum aHR 1.35 (95% CI, 0.99-1.85) compared with a standard diet. CONCLUSIONS: The duration of MV does not appear to depend on protein intake, whereas mortality in patients requiring MV may be improved by a standard protein intake. Adverse effects of a high protein intake cannot be excluded.


Assuntos
Respiração Artificial , Desmame do Respirador , Humanos , Estado Terminal/terapia , Unidades de Terapia Intensiva , Hospitalização
2.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36151740

RESUMO

Drug discovery and development is a complex and costly process. Machine learning approaches are being investigated to help improve the effectiveness and speed of multiple stages of the drug discovery pipeline. Of these, those that use Knowledge Graphs (KG) have promise in many tasks, including drug repurposing, drug toxicity prediction and target gene-disease prioritization. In a drug discovery KG, crucial elements including genes, diseases and drugs are represented as entities, while relationships between them indicate an interaction. However, to construct high-quality KGs, suitable data are required. In this review, we detail publicly available sources suitable for use in constructing drug discovery focused KGs. We aim to help guide machine learning and KG practitioners who are interested in applying new techniques to the drug discovery field, but who may be unfamiliar with the relevant data sources. The datasets are selected via strict criteria, categorized according to the primary type of information contained within and are considered based upon what information could be extracted to build a KG. We then present a comparative analysis of existing public drug discovery KGs and an evaluation of selected motivating case studies from the literature. Additionally, we raise numerous and unique challenges and issues associated with the domain and its datasets, while also highlighting key future research directions. We hope this review will motivate KGs use in solving key and emerging questions in the drug discovery domain.


Assuntos
Aprendizado de Máquina , Reconhecimento Automatizado de Padrão , Descoberta de Drogas , Conhecimento , Armazenamento e Recuperação da Informação
3.
PLoS Comput Biol ; 19(9): e1011301, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37669273

RESUMO

Many therapies in clinical trials are based on single drug-single target relationships. To further extend this concept to multi-target approaches using multi-targeted drugs, we developed a machine learning pipeline to unravel the target landscape of kinase inhibitors. This pipeline, which we call 3D-KINEssence, uses a new type of protein fingerprints (3D FP) based on the structure of kinases generated through a 3D convolutional neural network (3D-CNN). These 3D-CNN kinase fingerprints were matched to molecular Morgan fingerprints to predict the targets of each respective kinase inhibitor based on available bioactivity data. The performance of the pipeline was evaluated on two test sets: a sparse drug-target set where each drug is matched in most cases to a single target and also on a densely-covered drug-target set where each drug is matched to most if not all targets. This latter set is more challenging to train, given its non-exclusive character. Our model's root-mean-square error (RMSE) based on the two datasets was 0.68 and 0.8, respectively. These results indicate that 3D FP can predict the target landscape of kinase inhibitors at around 0.8 log units of bioactivity. Our strategy can be utilized in proteochemometric or chemogenomic workflows by consolidating the target landscape of kinase inhibitors.


Assuntos
Sistemas de Liberação de Medicamentos , Aprendizado de Máquina , Redes Neurais de Computação , Inibidores de Proteínas Quinases/farmacologia , Fluxo de Trabalho
4.
J Chem Inf Model ; 64(4): 1172-1186, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38300851

RESUMO

Drug-induced cardiotoxicity (DICT) is a major concern in drug development, accounting for 10-14% of postmarket withdrawals. In this study, we explored the capabilities of chemical and biological data to predict cardiotoxicity, using the recently released DICTrank data set from the United States FDA. We found that such data, including protein targets, especially those related to ion channels (e.g., hERG), physicochemical properties (e.g., electrotopological state), and peak concentration in plasma offer strong predictive ability for DICT. Compounds annotated with mechanisms of action such as cyclooxygenase inhibition could distinguish between most-concern and no-concern DICT. Cell Painting features for ER stress discerned most-concern cardiotoxic from nontoxic compounds. Models based on physicochemical properties provided substantial predictive accuracy (AUCPR = 0.93). With the availability of omics data in the future, using biological data promises enhanced predictability and deeper mechanistic insights, paving the way for safer drug development. All models from this study are available at https://broad.io/DICTrank_Predictor.


Assuntos
Cardiotoxicidade , Desenvolvimento de Medicamentos , Humanos , Cardiotoxicidade/etiologia , Cardiotoxicidade/metabolismo
5.
BMC Bioinformatics ; 24(1): 344, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715141

RESUMO

BACKGROUND: Understanding the Mechanism of Action (MoA) of a compound is an often challenging but equally crucial aspect of drug discovery that can help improve both its efficacy and safety. Computational methods to aid MoA elucidation usually either aim to predict direct drug targets, or attempt to understand modulated downstream pathways or signalling proteins. Such methods usually require extensive coding experience and results are often optimised for further computational processing, making them difficult for wet-lab scientists to perform, interpret and draw hypotheses from. RESULTS: To address this issue, we in this work present MAVEN (Mechanism of Action Visualisation and Enrichment), an R/Shiny app which allows for GUI-based prediction of drug targets based on chemical structure, combined with causal reasoning based on causal protein-protein interactions and transcriptomic perturbation signatures. The app computes a systems-level view of the mechanism of action of the input compound. This is visualised as a sub-network linking predicted or known targets to modulated transcription factors via inferred signalling proteins. The tool includes a selection of MSigDB gene set collections to perform pathway enrichment on the resulting network, and also allows for custom gene sets to be uploaded by the researcher. MAVEN is hence a user-friendly, flexible tool for researchers without extensive bioinformatics or cheminformatics knowledge to generate interpretable hypotheses of compound Mechanism of Action. CONCLUSIONS: MAVEN is available as a fully open-source tool at https://github.com/laylagerami/MAVEN with options to install in a Docker or Singularity container. Full documentation, including a tutorial on example data, is available at https://laylagerami.github.io/MAVEN .


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Biologia Computacional , Documentação , Sistemas de Liberação de Medicamentos
6.
BMC Bioinformatics ; 24(1): 154, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072707

RESUMO

BACKGROUND: Elucidating compound mechanism of action (MoA) is beneficial to drug discovery, but in practice often represents a significant challenge. Causal Reasoning approaches aim to address this situation by inferring dysregulated signalling proteins using transcriptomics data and biological networks; however, a comprehensive benchmarking of such approaches has not yet been reported. Here we benchmarked four causal reasoning algorithms (SigNet, CausalR, CausalR ScanR and CARNIVAL) with four networks (the smaller Omnipath network vs. 3 larger MetaBase™ networks), using LINCS L1000 and CMap microarray data, and assessed to what extent each factor dictated the successful recovery of direct targets and compound-associated signalling pathways in a benchmark dataset comprising 269 compounds. We additionally examined impact on performance in terms of the functions and roles of protein targets and their connectivity bias in the prior knowledge networks. RESULTS: According to statistical analysis (negative binomial model), the combination of algorithm and network most significantly dictated the performance of causal reasoning algorithms, with the SigNet recovering the greatest number of direct targets. With respect to the recovery of signalling pathways, CARNIVAL with the Omnipath network was able to recover the most informative pathways containing compound targets, based on the Reactome pathway hierarchy. Additionally, CARNIVAL, SigNet and CausalR ScanR all outperformed baseline gene expression pathway enrichment results. We found no significant difference in performance between L1000 data or microarray data, even when limited to just 978 'landmark' genes. Notably, all causal reasoning algorithms also outperformed pathway recovery based on input DEGs, despite these often being used for pathway enrichment. Causal reasoning methods performance was somewhat correlated with connectivity and biological role of the targets. CONCLUSIONS: Overall, we conclude that causal reasoning performs well at recovering signalling proteins related to compound MoA upstream from gene expression changes by leveraging prior knowledge networks, and that the choice of network and algorithm has a profound impact on the performance of causal reasoning algorithms. Based on the analyses presented here this is true for both microarray-based gene expression data as well as those based on the L1000 platform.


Assuntos
Benchmarking , Perfilação da Expressão Gênica , Perfilação da Expressão Gênica/métodos , Algoritmos , Análise em Microsséries , Expressão Gênica , Redes Reguladoras de Genes
7.
Bioinformatics ; 38(17): 4178-4184, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-35818973

RESUMO

MOTIVATION: In this article, we consider how to evaluate survival distribution predictions with measures of discrimination. This is non-trivial as discrimination measures are the most commonly used in survival analysis and yet there is no clear method to derive a risk prediction from a distribution prediction. We survey methods proposed in literature and software and consider their respective advantages and disadvantages. RESULTS: Whilst distributions are frequently evaluated by discrimination measures, we find that the method for doing so is rarely described in the literature and often leads to unfair comparisons or 'C-hacking'. We demonstrate by example how simple it can be to manipulate results and use this to argue for better reporting guidelines and transparency in the literature. We recommend that machine learning survival analysis software implements clear transformations between distribution and risk predictions in order to allow more transparent and accessible model evaluation. AVAILABILITY AND IMPLEMENTATION: The code used in the final experiment is available at https://github.com/RaphaelS1/distribution_discrimination.


Assuntos
Aprendizado de Máquina , Software , Publicações
8.
Toxicol Appl Pharmacol ; 459: 116342, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36502871

RESUMO

Functional changes to cardiomyocytes are undesirable during drug discovery and identifying the inotropic effects of compounds is hence necessary to decrease the risk of cardiovascular adverse effects in the clinic. Recently, approaches leveraging calcium transients in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have been developed to detect contractility changes, induced by a variety of mechanisms early during drug discovery projects. Although these approaches have been able to provide some predictive ability, we hypothesised that using additional waveform parameters could offer improved insights, as well as predictivity. In this study, we derived 25 parameters from each calcium transient waveform and developed a modified Random Forest method to predict the inotropic effects of the compounds. In total annotated data for 48 compounds were available for modelling, out of which 31 were inotropes. The results show that the Random Forest model with a modified purity criterion performed slightly better than an unmodified algorithm in terms of the Area Under the Curve, giving values of 0.84 vs 0.81 in a cross-validation, and outperformed the ToxCast Pipeline model, for which the highest value was 0.76 when using the best-performing parameter, PW10. Our study hence demonstrates that more advanced parameters derived from waveforms, in combination with additional machine learning methods, provide improved predictivity of cardiovascular risk associated with inotropic effects.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Células-Tronco Pluripotentes Induzidas , Humanos , Miócitos Cardíacos , Cálcio , Aprendizado de Máquina
9.
Mol Pharm ; 20(6): 3060-3072, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37096989

RESUMO

Pharmacokinetic (PK) parameters such as clearance (CL) and volume of distribution (Vd) have been the subject of previous in silico predictive models. However, having information of the concentration over time profile explicitly can provide additional value like time above MIC or AUC, etc., to understand both the efficacy and safety-related aspects of a compound. In this work, we developed machine learning models for plasma concentration-time profiles after both i.v. and p.o. dosing for a series of 17 in-house projects. For explanatory variables, MACCS Keys chemical descriptors as well as in silico and experimental in vitro PK parameters were used. The predictive accuracy of random forest (RF), message passing neural network, 2-compartment models using estimated CL and Vdss, and an average model (as a control experiment) was investigated using 5-fold cross-validation (5-fold CV) and leave-one-project-out validation (LOPO-V). The predictive accuracy of RF in 5-fold CV for i.v. and p.o. plasma concentration-time profiles was the best among the models studied, with an RMSE for i.v. dosing at 0.08, 1, and 8 h of 0.245, 0.474, and 0.462, respectively, and an RMSE for p.o. dosing at 0.25, 1, and 8 h of 0.500, 0.612, and 0.509, respectively. Furthermore, by investigating the importance of the in vitro PK parameters using the Gini index, we observed that the general prior knowledge in ADME research was reflected well in the respective feature importance of in vitro parameters such as predicted human Vd (hVd) for the initial distribution, mouse intrinsic CL and unbound fraction of mouse plasma for the elimination process, and Caco2 permeability for the absorption process. Also, this model is the first model that can predict twin peaks in the concentration-time profile much better than a baseline compartment model. Because of its combination of sufficient accuracy and speed of prediction, we found the model to be fit-for-purpose for practical lead optimization.


Assuntos
Modelos Biológicos , Algoritmo Florestas Aleatórias , Camundongos , Humanos , Animais , Células CACO-2 , Simulação por Computador , Administração Oral
10.
PLoS Comput Biol ; 18(6): e1010148, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35687583

RESUMO

Adverse event pathogenesis is often a complex process which compromises multiple events ranging from the molecular to the phenotypic level. In toxicology, Adverse Outcome Pathways (AOPs) aim to formalize this as temporal sequences of events, in which event relationships should be supported by causal evidence according to the tailored Bradford-Hill criteria. One of the criteria is whether events are consistently observed in a certain temporal order and, in this work, we study this time concordance using the concept of "first activation" as data-driven means to generate hypotheses on potentially causal mechanisms. As a case study, we analysed liver data from repeat-dose studies in rats from the TG-GATEs database which comprises measurements across eight timepoints, ranging from 3 hours to 4 weeks post-treatment. We identified time-concordant gene expression-derived events preceding adverse histopathology, which serves as surrogate readout for Drug-Induced Liver Injury (DILI). We find known mechanisms in DILI to be time-concordant, and show further that significance, frequency and log fold change (logFC) of differential expression are metrics which can additionally prioritize events although not necessary to be mechanistically relevant. Moreover, we used the temporal order of transcription factor (TF) expression and regulon activity to identify transcriptionally regulated TFs and subsequently combined this with prior knowledge on functional interactions to derive detailed gene-regulatory mechanisms, such as reduced Hnf4a activity leading to decreased expression and activity of Cebpa. At the same time, also potentially novel events are identified such as Sox13 which is highly significantly time-concordant and shows sustained activation over time. Overall, we demonstrate how time-resolved transcriptomics can derive and support mechanistic hypotheses by quantifying time concordance and how this can be combined with prior causal knowledge, with the aim of both understanding mechanisms of toxicity, as well as potential applications to the AOP framework. We make our results available in the form of a Shiny app (https://anikaliu.shinyapps.io/dili_cascades), which allows users to query events of interest in more detail.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Expressão Gênica , Regulação da Expressão Gênica , Ratos , Fatores de Transcrição
11.
Eur J Neurol ; 30(10): 3016-3031, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37515394

RESUMO

BACKGROUND AND PURPOSE: Transcranial direct current stimulation (tDCS) has been shown to improve signs of consciousness in a subset of patients with disorders of consciousness (DoC). However, no multicentre study confirmed its efficacy when applied during rehabilitation. In this randomized controlled double-blind study, the effects of tDCS whilst patients were in rehabilitation were tested at the group level and according to their diagnosis and aetiology to better target DoC patients who might repond to tDCS. METHODS: Patients received 2 mA tDCS or sham applied over the left prefrontal cortex for 4 weeks. Behavioural assessments were performed weekly and up to 3 months' follow-up. Analyses were conducted at the group and subgroup levels based on the diagnosis (minimally conscious state [MCS] and unresponsive wakefulness syndrome) and the aetiology (traumatic or non-traumatic). Interim analyses were planned to continue or stop the trial. RESULTS: The trial was stopped for futility when 62 patients from 10 centres were enrolled (44 ± 14 years, 37 ± 24.5 weeks post-injury, 18 women, 32 MCS, 39 non-traumatic). Whilst, at the group level, no treatment effect was found, the subgroup analyses at 3 months' follow-up revealed a significant improvement for patients in MCS and with traumatic aetiology. CONCLUSIONS: Transcranial direct current stimulation during rehabilitation does not seem to enhance patients' recovery. However, diagnosis and aetiology appear to be important factors leading to a response to the treatment. These findings bring novel insights into possible cortical plasticity changes in DoC patients given these differential results according to the subgroups of patients.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Humanos , Feminino , Estimulação Transcraniana por Corrente Contínua/métodos , Resultado do Tratamento , Transtornos da Consciência/terapia , Transtornos da Consciência/diagnóstico , Córtex Pré-Frontal , Estado Vegetativo Persistente/terapia , Estado Vegetativo Persistente/diagnóstico
12.
Environ Res ; 232: 116335, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37290620

RESUMO

Environmental factors such as exposure to ionizing radiations, certain environmental pollutants, and toxic chemicals are considered as risk factors in the development of breast cancer. Triple-negative breast cancer (TNBC) is a molecular variant of breast cancer that lacks therapeutic targets such as progesterone receptor, estrogen receptor, and human epidermal growth factor receptor-2 which makes the targeted therapy ineffective in TNBC patients. Therefore, identification of new therapeutic targets for the treatment of TNBC and the discovery of new therapeutic agents is the need of the hour. In this study, CXCR4 was found to be highly expressed in majority of breast cancer tissues and metastatic lymph nodes derived from TNBC patients. CXCR4 expression is positively correlated with breast cancer metastasis and poor prognosis of TNBC patients suggesting that suppression of CXCR4 expression could be a good strategy in the treatment of TNBC patients. Therefore, the effect of Z-guggulsterone (ZGA) on the expression of CXCR4 in TNBC cells was examined. ZGA downregulated protein and mRNA expression of CXCR4 in TNBC cells and proteasome inhibition or lysosomal stabilization had no effect on the ZGA-induced CXCR4 reduction. CXCR4 is under the transcriptional control of NF-κB, whereas ZGA was found to downregulate transcriptional activity of NF-κB. Functionally, ZGA downmodulated the CXCL12-driven migration/invasion in TNBC cells. Additionally, the effect of ZGA on growth of tumor was investigated in the orthotopic TNBC mice model. ZGA presented good inhibition of tumor growth and liver/lung metastasis in this model. Western blotting and immunohistochemical analysis indicated a reduction of CXCR4, NF-κB, and Ki67 in tumor tissues. Computational analysis suggested PXR agonism and FXR antagonism as targets of ZGA. In conclusion, CXCR4 was found to be overexpressed in majority of patient-derived TNBC tissues and ZGA abrogated the growth of TNBC tumors by partly targeting the CXCL12/CXCR4 signaling axis.


Assuntos
Neoplasias Hepáticas , Pregnenodionas , Neoplasias de Mama Triplo Negativas , Camundongos , Animais , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Quimiocina CXCL12/genética , Receptores CXCR4/genética
13.
Regul Toxicol Pharmacol ; 138: 105309, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36481280

RESUMO

Virtual Control Groups (VCGs) based on Historical Control Data (HCD) in preclinical toxicity testing have the potential to reduce animal usage. As a case study we retrospectively analyzed the impact of replacing Concurrent Control Groups (CCGs) with VCGs on the treatment-relatedness of 28 selected histopathological findings reported in either rat or dog in the eTOX database. We developed a novel methodology whereby statistical predictions of treatment-relatedness using either CCGs or VCGs of varying covariate similarity to CCGs were compared to designations from original toxicologist reports; and changes in agreement were used to quantify changes in study outcomes. Generally, the best agreement was achieved when CCGs were replaced with VCGs with the highest level of similarity; the same species, strain, sex, administration route, and vehicle. For example, balanced accuracies for rat findings were 0.704 (predictions based on CCGs) vs. 0.702 (predictions based on VCGs). Moreover, we identified covariates which resulted in poorer identification of treatment-relatedness. This was related to an increasing incidence rate divergence in HCD relative to CCGs. Future databases which collect data at the individual animal level including study details such as animal age and testing facility are required to build adequate VCGs to accurately identify treatment-related effects.


Assuntos
Testes de Toxicidade , Ratos , Animais , Cães , Estudos Retrospectivos , Grupos Controle , Bases de Dados Factuais
14.
Regul Toxicol Pharmacol ; 138: 105308, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36481279

RESUMO

Preclinical inter-species concordance can increase the predictivity of observations to the clinic, potentially reducing drug attrition caused by unforeseen adverse events. We quantified inter-species concordance of histopathological findings and target organ toxicities across four preclinical species in the eTOX database using likelihood ratios (LRs). This was done whilst only comparing findings between studies with similar compound exposure (Δ|Cmax| ≤ 1 log-unit), repeat-dosing duration, and animals of the same sex. We discovered 24 previously unreported significant inter-species associations between histopathological findings encoded by the HPATH ontology. More associations with strong positive concordance (33% LR+ > 10) relative to strong negative concordance (12.5% LR- < 0.1) were identified. Of the top 10 most positively concordant associations, 60% were computed between different histopathological findings indicating potential differences in inter-species pathogenesis. We also observed low inter-species target organ toxicity concordance. For example, liver toxicity concordance in short-term studies between female rats and dogs observed an average LR+ of 1.84, and an average LR- of 0.73. This was corroborated by similarly low concordance between rodents and non-rodents for 75 candidate drugs in AstraZeneca. This work provides new statistically significant associations between preclinical species, but finds that concordance is rare, particularly between the absence of findings.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Animais , Feminino , Ratos , Cães , Bases de Dados Factuais , Projetos de Pesquisa
15.
Bioinformatics ; 37(17): 2789-2791, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-33523131

RESUMO

SUMMARY: As machine learning has become increasingly popular over the last few decades, so too has the number of machine-learning interfaces for implementing these models. Whilst many R libraries exist for machine learning, very few offer extended support for survival analysis. This is problematic considering its importance in fields like medicine, bioinformatics, economics, engineering and more. mlr3proba provides a comprehensive machine-learning interface for survival analysis and connects with mlr3's general model tuning and benchmarking facilities to provide a systematic infrastructure for survival modelling and evaluation. AVAILABILITY AND IMPLEMENTATION: mlr3proba is available under an LGPL-3 licence on CRAN and at https://github.com/mlr-org/mlr3proba, with further documentation at https://mlr3book.mlr-org.com/survival.html.

16.
Chem Res Toxicol ; 35(4): 670-683, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-35333521

RESUMO

Estimation of points of departure (PoDs) from high-throughput transcriptomic data (HTTr) represents a key step in the development of next-generation risk assessment (NGRA). Current approaches mainly rely on single key gene targets, which are constrained by the information currently available in the knowledge base and make interpretation challenging as scientists need to interpret PoDs for thousands of genes or hundreds of pathways. In this work, we aimed to address these issues by developing a computational workflow to investigate the pathway concentration-response relationships in a way that is not fully constrained by known biology and also facilitates interpretation. We employed the Pathway-Level Information ExtractoR (PLIER) to identify latent variables (LVs) describing biological activity and then investigated in vitro LVs' concentration-response relationships using the ToxCast pipeline. We applied this methodology to a published transcriptomic concentration-response data set for 44 chemicals in MCF-7 cells and showed that our workflow can capture known biological activity and discriminate between estrogenic and antiestrogenic compounds as well as activity not aligning with the existing knowledge base, which may be relevant in a risk assessment scenario. Moreover, we were able to identify the known estrogen activity in compounds that are not well-established ER agonists/antagonists supporting the use of the workflow in read-across. Next, we transferred its application to chemical compounds tested in HepG2, HepaRG, and MCF-7 cells and showed that PoD estimates are in strong agreement with those estimated using a recently developed Bayesian approach (cor = 0.89) and in weak agreement with those estimated using a well-established approach such as BMDExpress2 (cor = 0.57). These results demonstrate the effectiveness of using PLIER in a concentration-response scenario to investigate pathway activity in a way that is not fully constrained by the knowledge base and to ease the biological interpretation and support the development of an NGRA framework with the ability to improve current risk assessment strategies for chemicals using new approach methodologies.


Assuntos
Toxicogenética , Transcriptoma , Teorema de Bayes , Estrogênios , Medição de Risco/métodos
17.
Mol Pharm ; 19(5): 1488-1504, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35412314

RESUMO

Animal pharmacokinetic (PK) data as well as human and animal in vitro systems are utilized in drug discovery to define the rate and route of drug elimination. Accurate prediction and mechanistic understanding of drug clearance and disposition in animals provide a degree of confidence for extrapolation to humans. In addition, prediction of in vivo properties can be used to improve design during drug discovery, help select compounds with better properties, and reduce the number of in vivo experiments. In this study, we generated machine learning models able to predict rat in vivo PK parameters and concentration-time PK profiles based on the molecular chemical structure and either measured or predicted in vitro parameters. The models were trained on internal in vivo rat PK data for over 3000 diverse compounds from multiple projects and therapeutic areas, and the predicted endpoints include clearance and oral bioavailability. We compared the performance of various traditional machine learning algorithms and deep learning approaches, including graph convolutional neural networks. The best models for PK parameters achieved R2 = 0.63 [root mean squared error (RMSE) = 0.26] for clearance and R2 = 0.55 (RMSE = 0.46) for bioavailability. The models provide a fast and cost-efficient way to guide the design of molecules with optimal PK profiles, to enable the prediction of virtual compounds at the point of design, and to drive prioritization of compounds for in vivo assays.


Assuntos
Aprendizado de Máquina , Modelos Biológicos , Animais , Disponibilidade Biológica , Descoberta de Drogas , Taxa de Depuração Metabólica , Preparações Farmacêuticas , Farmacocinética , Ratos
18.
BMC Neurol ; 22(1): 290, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927616

RESUMO

BACKGROUND: Even with high standards of acute care and neurological early rehabilitation (NER) a substantial number of patients with neurological conditions still need mechanical ventilation and/or airway protection by tracheal cannulas when discharged and hence home-based specialised intensive care nursing (HSICN). It may be possible to improve the home care situation with structured specialized long-term neurorehabilitation support and following up patients with neurorehabilitation teams. Consequently, more people might recover over an extended period to a degree that they were no longer dependent on HSICN. METHODS: This healthcare project and clinical trial implements a new specialised neurorehabilitation outreach service for people being discharged from NER with the need for HSICN. The multicentre, open, parallel-group RCT compares the effects of one year post-discharge specialized outpatient follow-up to usual care in people receiving HSICN. Participants will randomly be assigned to receive the new form of healthcare (intervention) or the standard healthcare (control) on a 2:1 basis. Primary outcome is the rate of weaning from mechanical ventilation and/or decannulation (primary outcome) after one year, secondary outcomes include both clinical and economic measures. 173 participants are required to corroborate a difference of 30 vs. 10% weaning success rate statistically with 80% power at a 5% significance level allowing for 15% attrition. DISCUSSION: The OptiNIV-Study will implement a new specialised neurorehabilitation outreach service and will determine its weaning success rates, other clinical outcomes, and cost-effectiveness compared to usual care for people in need for mechanical ventilation and/or tracheal cannula and hence HSICN after discharge from NER. TRIAL REGISTRATION: The trial OptiNIV has been registered in the German Clinical Trials Register (DRKS) since 18.01.2022 with the ID DRKS00027326 .


Assuntos
Assistência ao Convalescente , Reabilitação Neurológica , Cuidados Críticos , Humanos , Estudos Multicêntricos como Assunto , Alta do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto , Respiração Artificial
19.
J Chem Inf Model ; 62(15): 3486-3502, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35849793

RESUMO

The field of machine learning for drug discovery is witnessing an explosion of novel methods. These methods are often benchmarked on simple physicochemical properties such as solubility or general druglikeness, which can be readily computed. However, these properties are poor representatives of objective functions in drug design, mainly because they do not depend on the candidate compound's interaction with the target. By contrast, molecular docking is a widely applied method in drug discovery to estimate binding affinities. However, docking studies require a significant amount of domain knowledge to set up correctly, which hampers adoption. Here, we present dockstring, a bundle for meaningful and robust comparison of ML models using docking scores. dockstring consists of three components: (1) an open-source Python package for straightforward computation of docking scores, (2) an extensive dataset of docking scores and poses of more than 260,000 molecules for 58 medically relevant targets, and (3) a set of pharmaceutically relevant benchmark tasks such as virtual screening or de novo design of selective kinase inhibitors. The Python package implements a robust ligand and target preparation protocol that allows nonexperts to obtain meaningful docking scores. Our dataset is the first to include docking poses, as well as the first of its size that is a full matrix, thus facilitating experiments in multiobjective optimization and transfer learning. Overall, our results indicate that docking scores are a more realistic evaluation objective than simple physicochemical properties, yielding benchmark tasks that are more challenging and more closely related to real problems in drug discovery.


Assuntos
Benchmarking , Proteínas , Desenho de Fármacos , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Proteínas/química
20.
Crit Care ; 26(1): 7, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35012618

RESUMO

BACKGROUND: Proteins are an essential part of medical nutrition therapy in critically ill patients. Guidelines almost universally recommend a high protein intake without robust evidence supporting its use. METHODS: Using a large international database, we modelled associations between the hazard rate of in-hospital death and live hospital discharge (competing risks) and three categories of protein intake (low: < 0.8 g/kg per day, standard: 0.8-1.2 g/kg per day, high: > 1.2 g/kg per day) during the first 11 days after ICU admission (acute phase). Time-varying cause-specific hazard ratios (HR) were calculated from piece-wise exponential additive mixed models. We used the estimated model to compare five different hypothetical protein diets (an exclusively low protein diet, a standard protein diet administered early (day 1 to 4) or late (day 5 to 11) after ICU admission, and an early or late high protein diet). RESULTS: Of 21,100 critically ill patients in the database, 16,489 fulfilled inclusion criteria for the analysis. By day 60, 11,360 (68.9%) patients had been discharged from hospital, 4,192 patients (25.4%) had died in hospital, and 937 patients (5.7%) were still hospitalized. Median daily low protein intake was 0.49 g/kg [IQR 0.27-0.66], standard intake 0.99 g/kg [IQR 0.89- 1.09], and high intake 1.41 g/kg [IQR 1.29-1.60]. In comparison with an exclusively low protein diet, a late standard protein diet was associated with a lower hazard of in-hospital death: minimum 0.75 (95% CI 0.64, 0.87), and a higher hazard of live hospital discharge: maximum HR 1.98 (95% CI 1.72, 2.28). Results on hospital discharge, however, were qualitatively changed by a sensitivity analysis. There was no evidence that an early standard or a high protein intake during the acute phase was associated with a further improvement of outcome. CONCLUSIONS: Provision of a standard protein intake during the late acute phase may improve outcome compared to an exclusively low protein diet. In unselected critically ill patients, clinical outcome may not be improved by a high protein intake during the acute phase. Study registration ID number ISRCTN17829198.


Assuntos
Estado Terminal , Terapia Nutricional , Bases de Dados Factuais , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva
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