RESUMO
The human Ether-à-go-go-Related Gene (hERG) is a transmembrane protein that regulates cardiac action potential, and its inhibition can induce a potentially deadly cardiac syndrome. In vitro tests help identify hERG blockers at early stages; however, the high cost motivates searching for alternative, cost-effective methods. The primary goal of this study was to enhance the Pred-hERG tool for predicting hERG blockage. To achieve this, we developed new QSAR models that incorporated additional data, updated existing classificatory and multiclassificatory models, and introduced new regression models. Notably, we integrated SHAP (SHapley Additive exPlanations) values to offer a visual interpretation of these models. Utilizing the latest data from ChEMBL v30, encompassing over 14,364 compounds with hERG data, our binary and multiclassification models outperformed both the previous iteration of Pred-hERG and all publicly available models. Notably, the new version of our tool introduces a regression model for predicting hERG activity (pIC50). The optimal model demonstrated an R2 of 0.61 and an RMSE of 0.48, surpassing the only available regression model in the literature. Pred-hERG 5.0 now offers users a swift, reliable, and user-friendly platform for the early assessment of chemically induced cardiotoxicity through hERG blockage. The tool provides versatile outcomes, including (i) classificatory predictions of hERG blockage with prediction reliability, (ii) multiclassificatory predictions of hERG blockage with reliability, (iii) regression predictions with estimated pIC50 values, and (iv) probability maps illustrating the contribution of chemical fragments for each prediction. Furthermore, we implemented explainable AI analysis (XAI) to visualize SHAP values, providing insights into the contribution of each feature to binary classification predictions. A consensus prediction calculated based on the predictions of the three developed models is also present to assist the user's decision-making process. Pred-hERG 5.0 has been designed to be user-friendly, making it accessible to users without computational or programming expertise. The tool is freely available at http://predherg.labmol.com.br.
Assuntos
Canais de Potássio Éter-A-Go-Go , Relação Quantitativa Estrutura-Atividade , Humanos , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Canais de Potássio Éter-A-Go-Go/metabolismo , Medição de Risco , Análise de Regressão , Bloqueadores dos Canais de Potássio/farmacologia , Bloqueadores dos Canais de Potássio/químicaRESUMO
Exogenous metal particles and ions from implant devices are known to cause severe toxic events with symptoms ranging from adverse local tissue reactions to systemic toxicities, potentially leading to the development of cancers, heart conditions, and neurological disorders. Toxicity mechanisms, also known as Adverse Outcome Pathways (AOPs), that explain these metal-induced toxicities are severely understudied. Therefore, we deployed in silico structure- and knowledge-based approaches to identify proteome-level perturbations caused by metals and pathways that link these events to human diseases. We captured 177 structure-based, 347 knowledge-based, and 402 imputed metal-gene/protein relationships for chromium, cobalt, molybdenum, nickel, and titanium. We prioritized 72 proteins hypothesized to directly contact implant surfaces and contribute to adverse outcomes. Results of this exploratory analysis were formalized as structured AOPs. We considered three case studies reflecting the following possible situations: (i) the metal-protein-disease relationship was previously known; (ii) the metal-protein, protein-disease, and metal-disease relationships were individually known but were not linked (as a unified AOP); and (iii) one of three relationships was unknown and was imputed by our methods. These situations were illustrated by case studies on nickel-induced allergy/hypersensitivity, cobalt-induced heart failure, and titanium-induced periprosthetic osteolysis, respectively. All workflows, data, and results are freely available in https://github.com/DnlRKorn/Knowledge_Based_Metallomics/. An interactive view of select data is available at the ROBOKOP Neo4j Browser at http://robokopkg.renci.org/browser/.
Assuntos
Rotas de Resultados Adversos , Níquel , Humanos , Níquel/efeitos adversos , Titânio/toxicidade , Metais/toxicidade , Cobalto , CromoRESUMO
Safety assessment is an essential component of the regulatory acceptance of industrial chemicals. Previously, we have developed a model to predict the skin sensitization potential of chemicals for two assays, the human patch test and murine local lymph node assay, and implemented this model in a web portal. Here, we report on the substantially revised and expanded freely available web tool, Pred-Skin version 3.0. This up-to-date version of Pred-Skin incorporates multiple quantitative structure-activity relationship (QSAR) models developed with in vitro, in chemico, and mice and human in vivo data, integrated into a consensus naïve Bayes model that predicts human effects. Individual QSAR models were generated using skin sensitization data derived from human repeat insult patch tests, human maximization tests, and mouse local lymph node assays. In addition, data for three validated alternative methods, the direct peptide reactivity assay, KeratinoSens, and the human cell line activation test, were employed as well. Models were developed using open-source tools and rigorously validated according to the best practices of QSAR modeling. Predictions obtained from these models were then used to build a naïve Bayes model for predicting human skin sensitization with the following external prediction accuracy: correct classification rate (89%), sensitivity (94%), positive predicted value (91%), specificity (84%), and negative predicted value (89%). As an additional assessment of model performance, we identified 11 cosmetic ingredients known to cause skin sensitization but were not included in our training set, and nine of them were accurately predicted as sensitizers by our models. Pred-Skin can be used as a reliable alternative to animal tests for predicting human skin sensitization.
Assuntos
Cosméticos/efeitos adversos , Testes Cutâneos , Pele/efeitos dos fármacos , Animais , Teorema de Bayes , Cosméticos/química , Humanos , Camundongos , Relação Quantitativa Estrutura-AtividadeRESUMO
Malaria is an infectious disease that affects over 216 million people worldwide, killing over 445,000 patients annually. Due to the constant emergence of parasitic resistance to the current antimalarial drugs, the discovery of new drug candidates is a major global health priority. Aiming to make the drug discovery processes faster and less expensive, we developed binary and continuous Quantitative Structure-Activity Relationships (QSAR) models implementing deep learning for predicting antiplasmodial activity and cytotoxicity of untested compounds. Then, we applied the best models for a virtual screening of a large database of chemical compounds. The top computational predictions were evaluated experimentally against asexual blood stages of both sensitive and multi-drug-resistant Plasmodium falciparum strains. Among them, two compounds, LabMol-149 and LabMol-152, showed potent antiplasmodial activity at low nanomolar concentrations (EC50 <500 nM) and low cytotoxicity in mammalian cells. Therefore, the computational approach employing deep learning developed here allowed us to discover two new families of potential next generation antimalarial agents, which are in compliance with the guidelines and criteria for antimalarial target candidates.
Assuntos
Antimaláricos/química , Antimaláricos/uso terapêutico , Aprendizado Profundo , Descoberta de Drogas/métodos , Malária/tratamento farmacológico , Humanos , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes , Relação Estrutura-AtividadeRESUMO
The COVID-19 pandemic has catalyzed a widespread effort to identify drug candidates and biological targets of relevance to SARS-COV-2 infection, which resulted in large numbers of publications on this subject. We have built the COVID-19 Knowledge Extractor (COKE), a web application to extract, curate, and annotate essential drug-target relationships from the research literature on COVID-19. SciBiteAI ontological tagging of the COVID Open Research Data set (CORD-19), a repository of COVID-19 scientific publications, was employed to identify drug-target relationships. Entity identifiers were resolved through lookup routines using UniProt and DrugBank. A custom algorithm was used to identify co-occurrences of the target protein and drug terms, and confidence scores were calculated for each entity pair. COKE processing of the current CORD-19 database identified about 3000 drug-protein pairs, including 29 unique proteins and 500 investigational, experimental, and approved drugs. Some of these drugs are presently undergoing clinical trials for COVID-19. The COKE repository and web application can serve as a useful resource for drug repurposing against SARS-CoV-2. COKE is freely available at https://coke.mml.unc.edu/, and the code is available at https://github.com/DnlRKorn/CoKE.
Assuntos
COVID-19 , Preparações Farmacêuticas , Antivirais , Reposicionamento de Medicamentos , Humanos , Pandemias , SARS-CoV-2RESUMO
Computational methods to predict molecular properties regarding safety and toxicology represent alternative approaches to expedite drug development, screen environmental chemicals, and thus significantly reduce associated time and costs. There is a strong need and interest in the development of computational methods that yield reliable predictions of toxicity, and many approaches, including the recently introduced deep neural networks, have been leveraged towards this goal. Herein, we report on the collection, curation, and integration of data from the public data sets that were the source of the ChemIDplus database for systemic acute toxicity. These efforts generated the largest publicly available such data set comprising > 80,000 compounds measured against a total of 59 acute systemic toxicity end points. This data was used for developing multiple single- and multitask models utilizing random forest, deep neural networks, convolutional, and graph convolutional neural network approaches. For the first time, we also reported the consensus models based on different multitask approaches. To the best of our knowledge, prediction models for 36 of the 59 end points have never been published before. Furthermore, our results demonstrated a significantly better performance of the consensus model obtained from three multitask learning approaches that particularly predicted the 29 smaller tasks (less than 300 compounds) better than other models developed in the study. The curated data set and the developed models have been made publicly available at https://github.com/ncats/ld50-multitask, https://predictor.ncats.io/, and https://cactus.nci.nih.gov/download/acute-toxicity-db (data set only) to support regulatory and research applications.
Assuntos
Aprendizado Profundo , Consenso , Bases de Dados Factuais , Redes Neurais de ComputaçãoRESUMO
New Approach Methodologies (NAMs) that employ artificial intelligence (AI) for predicting adverse effects of chemicals have generated optimistic expectations as alternatives to animal testing. However, the major underappreciated challenge in developing robust and predictive AI models is the impact of the quality of the input data on the model accuracy. Indeed, poor data reproducibility and quality have been frequently cited as factors contributing to the crisis in biomedical research, as well as similar shortcomings in the fields of toxicology and chemistry. In this article, we review the most recent efforts to improve confidence in the robustness of toxicological data and investigate the impact that data curation has on the confidence in model predictions. We also present two case studies demonstrating the effect of data curation on the performance of AI models for predicting skin sensitisation and skin irritation. We show that, whereas models generated with uncurated data had a 7-24% higher correct classification rate (CCR), the perceived performance was, in fact, inflated owing to the high number of duplicates in the training set. We assert that data curation is a critical step in building computational models, to help ensure that reliable predictions of chemical toxicity are achieved through use of the models.
Assuntos
Alternativas aos Testes com Animais , Inteligência Artificial , Animais , Simulação por Computador , Confiabilidade dos Dados , Reprodutibilidade dos TestesRESUMO
Small, colloidally aggregating molecules (SCAMs) are the most common source of false positives in high-throughput screening (HTS) campaigns. Although SCAMs can be experimentally detected and suppressed by the addition of detergent in the assay buffer, detergent sensitivity is not routinely monitored in HTS. Computational methods are thus needed to flag potential SCAMs during HTS triage. In this study, we have developed and rigorously validated quantitative structure-interference relationship (QSIR) models of detergent-sensitive aggregation in several HTS campaigns under various assay conditions and screening concentrations. In particular, we have modeled detergent-sensitive aggregation in an AmpC ß-lactamase assay, the preferred HTS counter-screen for aggregation, as well as in another assay that measures cruzain inhibition. Our models increase the accuracy of aggregation prediction by â¼53% in the ß-lactamase assay and by â¼46% in the cruzain assay compared to previously published methods. We also discuss the importance of both assay conditions and screening concentrations in the development of QSIR models for various interference mechanisms besides aggregation. The models developed in this study are publicly available for fast prediction within the SCAM detective web application (https://scamdetective.mml.unc.edu/).
Assuntos
Ensaios de Triagem em Larga EscalaRESUMO
Quantitative structure-activity relationships (QSAR) models are often seen as a "black box" because they are considered difficult to interpret. Meanwhile, qualitative approaches, e.g., structural alerts (SA) or read-across, provide mechanistic insight, which is preferred for regulatory purposes, but predictive accuracy of such approaches is often low. Herein, we introduce the chemistry-wide association study (CWAS) approach, a novel framework that both addresses such deficiencies and combines advantages of statistical QSAR and alert-based approaches. The CWAS framework consists of the following steps: (i) QSAR model building for an end point of interest, (ii) identification of key chemical features, (iii) determination of communities of such features disproportionately co-occurring more frequently in the active than in the inactive class, and (iv) assembling these communities to form larger (and not necessarily chemically connected) novel structural alerts with high specificity. As a proof-of-concept, we have applied CWAS to model Ames mutagenicity and Stevens-Johnson Syndrome (SJS). For the well-studied Ames mutagenicity data set, we identified 76 important individual fragments and assembled co-occurring fragments into SA both replicative of known as well as representing novel mutagenicity alerts. For the SJS data set, we identified 29 important fragments and assembled co-occurring communities into SA including both known and novel alerts. In summary, we demonstrate that CWAS provides a new framework to interpret predictive QSAR models and derive refined structural alerts for more effective design and safety assessment of drugs and drug candidates.
Assuntos
Descoberta de Drogas/métodos , Testes de Mutagenicidade/métodos , Preparações Farmacêuticas/química , Relação Quantitativa Estrutura-Atividade , Síndrome de Stevens-Johnson/etiologia , Bases de Dados Factuais , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Humanos , Modelos BiológicosRESUMO
Multiple approaches to quantitative structure-activity relationship (QSAR) modeling using various statistical or machine learning techniques and different types of chemical descriptors have been developed over the years. Oftentimes models are used in consensus to make more accurate predictions at the expense of model interpretation. We propose a simple, fast, and reliable method termed Multi-Descriptor Read Across (MuDRA) for developing both accurate and interpretable models. The method is conceptually related to the well-known kNN approach but uses different types of chemical descriptors simultaneously for similarity assessment. To benchmark the new method, we have built MuDRA models for six different end points (Ames mutagenicity, aquatic toxicity, hepatotoxicity, hERG liability, skin sensitization, and endocrine disruption) and compared the results with those generated with conventional consensus QSAR modeling. We find that models built with MuDRA show consistently high external accuracy similar to that of conventional QSAR models. However, MuDRA models excel in terms of transparency, interpretability, and computational efficiency. We posit that due to its methodological simplicity and reliable predictive accuracy, MuDRA provides a powerful alternative to a much more complex consensus QSAR modeling. MuDRA is implemented and freely available at the Chembench web portal ( https://chembench.mml.unc.edu/mudra ).
Assuntos
Relação Quantitativa Estrutura-Atividade , Algoritmos , Bases de Dados Factuais , Humanos , Internet , Modelos Biológicos , Mutagênicos/toxicidade , Software , Testes de ToxicidadeRESUMO
Chemically induced skin sensitization is a complex immunological disease with a profound impact on quality of life and working ability. Despite some progress in developing alternative methods for assessing the skin sensitization potential of chemical substances, there is no in vitro test that correlates well with human data. Computational QSAR models provide a rapid screening approach and contribute valuable information for the assessment of chemical toxicity. We describe the development of a freely accessible web-based and mobile application for the identification of potential skin sensitizers. The application is based on previously developed binary QSAR models of skin sensitization potential from human (109 compounds) and murine local lymph node assay (LLNA, 515 compounds) data with good external correct classification rate (0.70-0.81 and 0.72-0.84, respectively). We also included a multiclass skin sensitization potency model based on LLNA data (accuracy ranging between 0.73 and 0.76). When a user evaluates a compound in the web app, the outputs are (i) binary predictions of human and murine skin sensitization potential; (ii) multiclass prediction of murine skin sensitization; and (iii) probability maps illustrating the predicted contribution of chemical fragments. The app is the first tool available that incorporates quantitative structure-activity relationship (QSAR) models based on human data as well as multiclass models for LLNA. The Pred-Skin web app version 1.0 is freely available for the web, iOS, and Android (in development) at the LabMol web portal ( http://labmol.com.br/predskin/ ), in the Apple Store, and on Google Play, respectively. We will continuously update the app as new skin sensitization data and respective models become available.
Assuntos
Alérgenos , Dermatite de Contato , Internet , Pele , Software , Alérgenos/toxicidade , Animais , Simulação por Computador , Bases de Dados de Compostos Químicos , Humanos , Ensaio Local de Linfonodo , Camundongos , Relação Quantitativa Estrutura-Atividade , Pele/efeitos dos fármacos , Pele/patologia , Fatores de TempoRESUMO
Eosinophilic meningoencephalitis is an endemic zoonosis in Southeast Asia and the Pacific Islands, but in recent years, new cases have been reported in various countries outside these regions, including Brazil, where it is considered an emerging disease. In this study, the effect of infection by the nematode Angiostrongylus cantonensis, one of the main etiologic agent of this disease, on the reproductive biology of the planorbid snails Biomphalaria straminea and B. tenagophila was investigated during the pre-patent period. Alterations in the reproductive biology of B. straminea and B. tenagophila were analyzed in laboratory-reared specimens infected by A. cantonensis during 21days; the number of eggs, number of egg masses, number of eggs/mass, number of eggs/snail, viable eggs/snail, survival and galactogen content in the albumen gland were measured. The results indicated the occurrence of initial compensation in reproductive effort in both snail species, but at different moments in the pre-patent period. More specifically, a reduction of 46.53% in the eggs/egg mass ratio in infected B. straminea was observed, a reflection of a 50% decline in the concentration of galactogen contained in the albumen gland. Changes in this parameter were also noted in B. tenagophila, but only at the end of the study period, with a reduction of 15.49%. Histological analyses indicate that changes observed can be explained by the tissue damages caused by the migration and development of the larvae. These results shed more light on the host-parasite relationship and indicate the importance of studying reproductive aspects for efforts to control infected snails. Considering that terrestrial snails can also transmit eosinophilic meningitis (in addition to aquatic mollusks), the data obtained expand knowledge of this host-parasite relationship and provide support for programs to control this zoonosis.
Assuntos
Angiostrongylus cantonensis , Biomphalaria/microbiologia , Reprodução/fisiologia , Infecções por Strongylida/fisiopatologia , Animais , Biomphalaria/fisiologia , Interações Hospedeiro-ParasitaRESUMO
The objective of this study was to identify thyroid hormones and to examine their putative site of synthesis in Achatina fulica snails. For this purpose, radioimmunoassays were performed for T3 and T4 before and after long starvation with or without hemolymph deproteinization. Sodium/iodide symporter activity in vivo was analyzed through 125I administration with and without KClO4 pretreatment. Only T4 was detected, and its concentration decreased due to starvation or deproteinization. However, high-performance liquid chromatography analysis also showed the presence of T2 and T3 apart from T4, but rT3 was not detected in the A. fulica hemolymph. The sodium/iodide symporter activity was greater in cerebral ganglia than digestive gland, but KClO4 treatment did not inhibit iodide uptake in any of the tissues analyzed. Altogether, our data confirm for the first time the presence of thyroid hormones in A. fulica snails and suggest their participation in the metabolism control in this species, although the putative site of hormone biosynthesis remains to be elucidated.
Assuntos
Caramujos/química , Tiroxina/análise , Animais , Transporte Biológico , Cromatografia Líquida de Alta Pressão , Hemolinfa , Simportadores de Cloreto de Sódio , Tiroxina/metabolismoRESUMO
Angiostrongylus cantonensis is considered the main agent responsible for human eosinophilic meningoencephalitis. This parasite has low specificity for mollusk hosts and it can also use aquatic snails as auxiliary hosts. Studies based on the metabolic profile of Biomphalaria spp. infected by A. cantonensis have been conducted to observe parasite-host interactions. In the present study, the glucose content in the hemolymph and glycogen content in the digestive gland and cephalopedal mass of Biomphalaria tenagophila and Biomphalaria straminea experimentally infected by A. cantonensis were evaluated, along with the activity of LDH. The snails were dissected from 6 to 21days after infection to collect the hemolymph and separate the tissues. Decreases of 96% and 6.4% in the glucose content triggered a transition from aerobic to anaerobic metabolism in the two infected snail species, B. straminea and B. tenagophila, respectively. That finding was confirmed by high-performance liquid chromatography. These results indicate that when infected, these snails are able to change their metabolic profile, suggesting a strategy to maintain their homeostatic balance.
Assuntos
Angiostrongylus cantonensis/fisiologia , Biomphalaria/metabolismo , Biomphalaria/parasitologia , Aerobiose , Animais , Biomphalaria/química , Cromatografia Líquida de Alta Pressão , Glucose/análise , Glicogênio/análise , Hemolinfa/química , Hemolinfa/enzimologia , Homeostase , Interações Hospedeiro-Parasita , L-Lactato Desidrogenase/metabolismoRESUMO
Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R(2)=0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q(2)ext=0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential.
Assuntos
Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/metabolismo , Substâncias Perigosas/intoxicação , Absorção Cutânea/fisiologia , Pele/efeitos dos fármacos , Pele/metabolismo , Simulação por Computador , Bases de Dados Factuais , Dermatite Alérgica de Contato/imunologia , Humanos , Modelos Teóricos , Permeabilidade , Relação Quantitativa Estrutura-Atividade , Pele/imunologia , SoftwareRESUMO
Repetitive exposure to a chemical agent can induce an immune reaction in inherently susceptible individuals that leads to skin sensitization. Although many chemicals have been reported as skin sensitizers, there have been very few rigorously validated QSAR models with defined applicability domains (AD) that were developed using a large group of chemically diverse compounds. In this study, we have aimed to compile, curate, and integrate the largest publicly available dataset related to chemically-induced skin sensitization, use this data to generate rigorously validated and QSAR models for skin sensitization, and employ these models as a virtual screening tool for identifying putative sensitizers among environmental chemicals. We followed best practices for model building and validation implemented with our predictive QSAR workflow using Random Forest modeling technique in combination with SiRMS and Dragon descriptors. The Correct Classification Rate (CCR) for QSAR models discriminating sensitizers from non-sensitizers was 71-88% when evaluated on several external validation sets, within a broad AD, with positive (for sensitizers) and negative (for non-sensitizers) predicted rates of 85% and 79% respectively. When compared to the skin sensitization module included in the OECD QSAR Toolbox as well as to the skin sensitization model in publicly available VEGA software, our models showed a significantly higher prediction accuracy for the same sets of external compounds as evaluated by Positive Predicted Rate, Negative Predicted Rate, and CCR. These models were applied to identify putative chemical hazards in the Scorecard database of possible skin or sense organ toxicants as primary candidates for experimental validation.
Assuntos
Dermatite Alérgica de Contato/etiologia , Substâncias Perigosas/intoxicação , Pele/efeitos dos fármacos , Bases de Dados Factuais , Dermatite Alérgica de Contato/imunologia , Humanos , Modelos Químicos , Modelos Imunológicos , Relação Quantitativa Estrutura-Atividade , Pele/imunologia , SoftwareRESUMO
Carbohydrate metabolism plays an important role in the physiology and maintenance of energy stores within living organisms. However, when organisms are exposed to adverse physiological conditions, such as during pathogenic infection, these organisms begin to use alternative substrates (proteins and lipids) for energy production. This paper studied the carbohydrate metabolism of Rhipicephalus microplus after infection with Beauveria bassiana and Metarhizium anisopliae. The parameters evaluated were glucose concentration, enzymatic activities of lactate dehydrogenase (LDH), alanine aminostransferase (ALT) and aspartate aminostransferase (AST), amounts of uric acid and urea in the hemolymph, and amount of glycogen in the fat body. The results showed changes in nitrogenous products, including an increase in the amount of urea detected 48 h after infection with both fungi. The enzymatic activities of LDH, ALT, and AST were increased after infection. The amount of glucose was increased 24 h after infection with B. bassiana and was reduced 48 h after infection with both fungi. The amount of glycogen in the fat body was reduced at different times of infection with both fungi. These results demonstrate, for the first time, the changes in carbohydrate metabolism of R. microplus after infection with M. anisopliae and B. bassiana and contribute to a better understanding of this host-parasite relationship. Together with knowledge of diseases that affect these ticks and their susceptibility to entomopathogens, an understanding of tick physiology will be necessary for the effective implementation of current biological control methods and will assist in the discovery of new methods to control this ectoparasite.
Assuntos
Beauveria/fisiologia , Metarhizium/fisiologia , Controle Biológico de Vetores/métodos , Rhipicephalus/fisiologia , Animais , Interações Hospedeiro-Patógeno , Rhipicephalus/microbiologiaRESUMO
Hits from high-throughput screening (HTS) of chemical libraries are often false positives due to their interference with assay detection technology. In response, we generated the largest publicly available library of chemical liabilities and developed "Liability Predictor," a free web tool to predict HTS artifacts. More specifically, we generated, curated, and integrated HTS data sets for thiol reactivity, redox activity, and luciferase (firefly and nano) activity and developed and validated quantitative structure-interference relationship (QSIR) models to predict these nuisance behaviors. The resulting models showed 58-78% external balanced accuracy for 256 external compounds per assay. QSIR models developed and validated herein identify nuisance compounds among experimental hits more reliably than do popular PAINS filters. Both the models and the curated data sets were implemented in "Liability Predictor," publicly available at https://liability.mml.unc.edu/. "Liability Predictor" may be used as part of chemical library design or for triaging HTS hits.
Assuntos
Artefatos , Ensaios de Triagem em Larga Escala , Ensaios de Triagem em Larga Escala/métodos , Bibliotecas de Moléculas Pequenas/químicaRESUMO
Aims: The development of safe and effective therapies for treating paracoccidioidomycosis using computational strategies were employed to discover anti-Paracoccidioides compounds. Materials & methods: We 1) collected, curated and integrated the largest library of compounds tested against Paracoccidioides spp.; 2) employed a similarity search to virtually screen the ChemBridge database and select nine compounds for experimental evaluation; 3) performed an experimental evaluation to determine the minimum inhibitory concentration and minimum fungicidal concentration as well as cytotoxicity; and 4) employed computational tools to identify potential targets for the most active compounds. Seven compounds presented activity against Paracoccidioides spp. Conclusion: These compounds are new hits with a predicted mechanisms of action, making them potentially attractive to develop new compounds.
Assuntos
Paracoccidioides , Paracoccidioidomicose , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Quimioinformática , Paracoccidioidomicose/tratamento farmacológico , Testes de Sensibilidade MicrobianaRESUMO
Understanding the origins of past and present viral epidemics is critical in preparing for future outbreaks. Many viruses, including SARS-CoV-2, have led to significant consequences not only due to their virulence, but also because we were unprepared for their emergence. We need to learn from large amounts of data accumulated from well-studied, past pandemics and employ modern informatics and therapeutic development technologies to forecast future pandemics and help minimize their potential impacts. While acknowledging the complexity and difficulties associated with establishing reliable outbreak predictions, herein we provide a perspective on the regions of the world that are most likely to be impacted by future outbreaks. We specifically focus on viruses with epidemic potential, namely SARS-CoV-2, MERS-CoV, DENV, ZIKV, MAYV, LASV, noroviruses, influenza, Nipah virus, hantaviruses, Oropouche virus, MARV, and Ebola virus, which all require attention from both the public and scientific community to avoid societal catastrophes like COVID-19. Based on our literature review, data analysis, and outbreak simulations, we posit that these future viral epidemics are unavoidable, but that their societal impacts can be minimized by strategic investment into basic virology research, epidemiological studies of neglected viral diseases, and antiviral drug discovery.