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1.
Bioinformatics ; 38(4): 1075-1086, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34788368

RESUMO

MOTIVATION: Accurate disease diagnosis and prognosis based on omics data rely on the effective identification of robust prognostic and diagnostic markers that reflect the states of the biological processes underlying the disease pathogenesis and progression. In this article, we present GCNCC, a Graph Convolutional Network-based approach for Clustering and Classification, that can identify highly effective and robust network-based disease markers. Based on a geometric deep learning framework, GCNCC learns deep network representations by integrating gene expression data with protein interaction data to identify highly reproducible markers with consistently accurate prediction performance across independent datasets possibly from different platforms. GCNCC identifies these markers by clustering the nodes in the protein interaction network based on latent similarity measures learned by the deep architecture of a graph convolutional network, followed by a supervised feature selection procedure that extracts clusters that are highly predictive of the disease state. RESULTS: By benchmarking GCNCC based on independent datasets from different diseases (psychiatric disorder and cancer) and different platforms (microarray and RNA-seq), we show that GCNCC outperforms other state-of-the-art methods in terms of accuracy and reproducibility. AVAILABILITY AND IMPLEMENTATION: https://github.com/omarmaddouri/GCNCC. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Redes Neurais de Computação , Mapas de Interação de Proteínas , Humanos , Reprodutibilidade dos Testes
2.
Bioinformatics ; 37(10): 1401-1410, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-33165517

RESUMO

MOTIVATION: Alignment of protein-protein interaction networks can be used for the unsupervised prediction of functional modules, such as protein complexes and signaling pathways, that are conserved across different species. To date, various algorithms have been proposed for biological network alignment, many of which attempt to incorporate topological similarity between the networks into the alignment process with the goal of constructing accurate and biologically meaningful alignments. Especially, random walk models have been shown to be effective for quantifying the global topological relatedness between nodes that belong to different networks by diffusing node-level similarity along the interaction edges. However, these schemes are not ideal for capturing the local topological similarity between nodes. RESULTS: In this article, we propose MONACO, a novel and versatile network alignment algorithm that finds highly accurate pairwise and multiple network alignments through the iterative optimal matching of 'local' neighborhoods around focal nodes. Extensive performance assessment based on real networks as well as synthetic networks, for which the ground truth is known, demonstrates that MONACO clearly and consistently outperforms all other state-of-the-art network alignment algorithms that we have tested, in terms of accuracy, coherence and topological quality of the aligned network regions. Furthermore, despite the sharply enhanced alignment accuracy, MONACO remains computationally efficient and it scales well with increasing size and number of networks. AVAILABILITY AND IMPLEMENTATION: Matlab implementation is freely available at https://github.com/bjyoontamu/MONACO. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Algoritmos , Biologia Computacional , Difusão
3.
Colorectal Dis ; 23(4): 901-910, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33247529

RESUMO

AIM: The aim was to determine the efficacy of probiotics in restoring bowel function following ileostomy reversal in patients with rectal cancer. METHOD: This was a pilot, randomized, double-blind, placebo-controlled trial. The probiotic used in this study, Lactobacillus plantarum CJLP243, was derived from kimchi. Patients were randomly allocated to a probiotic or placebo group and medication was taken once daily from preoperative day 1 to day 21. Primary outcomes were the Memorial Sloan Kettering Cancer Centre Bowel Function Index (MSKCC BFI) instrument and the low anterior resection syndrome score. The secondary outcomes were the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 and CR29 questionnaire responses. RESULTS: Forty patients were enrolled, and 36 patients (probiotics, n = 17; placebo, n = 19) completed the primary outcomes. Total scores for the MSKCC questionnaire (56.2 ± 12.0 vs. 55.0 ± 10.7, P = 0.356) and low anterior resection syndrome scores (33.3 ± 7.6 vs. 36.0 ± 5.3, P = 0.257) were not significantly different between the probiotic and placebo groups, respectively. In the MSKCC BFI, the postoperative dietary scale score at week 1 was significantly higher in the probiotic group (13.1 ± 3.8 vs. 9.0 ± 3.0, P < 0.001). There were no other significant differences between the two groups for any other questionnaire scores. CONCLUSION: There were no significant effects supporting the use of a probiotic for improved bowel function in patients following ileostomy reversal. Nevertheless, the administration of probiotics showed trends toward improvements in some subscale bowel function measures, suggesting further studies may be warranted.


Assuntos
Probióticos , Neoplasias Retais , Método Duplo-Cego , Humanos , Ileostomia , Complicações Pós-Operatórias/prevenção & controle , Probióticos/uso terapêutico , Qualidade de Vida , Neoplasias Retais/cirurgia , Resultado do Tratamento
4.
BMC Genomics ; 21(Suppl 10): 615, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33208103

RESUMO

BACKGROUND: The current computational methods on identifying conserved protein complexes across multiple Protein-Protein Interaction (PPI) networks suffer from the lack of explicit modeling of the desired topological properties within conserved protein complexes as well as their scalability. RESULTS: To overcome those issues, we propose a scalable algorithm-ClusterM-for identifying conserved protein complexes across multiple PPI networks through the integration of network topology and protein sequence similarity information. ClusterM overcomes the computational barrier that existed in previous methods, where the complexity escalates exponentially when handling an increasing number of PPI networks; and it is able to detect conserved protein complexes with both topological separability and cohesive protein sequence conservation. On two independent compendiums of PPI networks from Saccharomyces cerevisiae (Sce, yeast), Drosophila melanogaster (Dme, fruit fly), Caenorhabditis elegans (Cel, worm), and Homo sapiens (Hsa, human), we demonstrate that ClusterM outperforms other state-of-the-art algorithms by a significant margin and is able to identify de novo conserved protein complexes across four species that are missed by existing algorithms. CONCLUSIONS: ClusterM can better capture the desired topological property of a typical conserved protein complex, which is densely connected within the complex while being well-separated from the rest of the networks. Furthermore, our experiments have shown that ClusterM is highly scalable and efficient when analyzing multiple PPI networks.


Assuntos
Biologia Computacional , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Algoritmos , Animais , Caenorhabditis elegans/genética , Drosophila melanogaster/genética , Humanos , Complexo Repressor Polycomb 1 , Saccharomyces cerevisiae/genética
5.
Bioinformatics ; 35(7): 1133-1141, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30169792

RESUMO

MOTIVATION: Non-coding RNAs (ncRNAs) are known to play crucial roles in various biological processes, and there is a pressing need for accurate computational detection methods that could be used to efficiently scan genomes to detect novel ncRNAs. However, unlike coding genes, ncRNAs often lack distinctive sequence features that could be used for recognizing them. Although many ncRNAs are known to have a well conserved secondary structure, which provides useful cues for computational prediction, it has been also shown that a structure-based approach alone may not be sufficient for detecting ncRNAs in a single sequence. Currently, the most effective ncRNA detection methods combine structure-based techniques with a comparative genome analysis approach to improve the prediction performance. RESULTS: In this paper, we propose RNAdetect, a computational method incorporating novel features for accurate detection of ncRNAs in combination with comparative genome analysis. Given a sequence alignment, RNAdetect can accurately detect the presence of functional ncRNAs by incorporating novel predictive features based on the concept of generalized ensemble defect (GED), which assesses the degree of structure conservation across multiple related sequences and the conformation of the individual folding structures to a common consensus structure. Furthermore, n-gram models (NGMs) are used to extract features that can effectively capture sequence homology to known ncRNA families. Utilization of NGMs can enhance the detection of ncRNAs that have sparse folding structures with many unpaired bases. Extensive performance evaluation based on the Rfam database and bacterial genomes demonstrate that RNAdetect can accurately and reliably detect novel ncRNAs, outperforming the current state-of-the-art methods. AVAILABILITY AND IMPLEMENTATION: The source code for RNAdetect and the benchmark data used in this paper can be downloaded at https://github.com/bjyoontamu/RNAdetect.


Assuntos
Genoma Bacteriano , RNA não Traduzido/genética , Hibridização Genômica Comparativa , Biologia Computacional , Conformação de Ácido Nucleico , Alinhamento de Sequência , Software
6.
Bioinformatics ; 35(17): 2941-2948, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30629122

RESUMO

MOTIVATION: For many RNA families, the secondary structure is known to be better conserved among the member RNAs compared to the primary sequence. For this reason, it is important to consider the underlying folding structures when aligning RNA sequences, especially for those with relatively low sequence identity. Given a set of RNAs with unknown structures, simultaneous RNA alignment and folding algorithms aim to accurately align the RNAs by jointly predicting their consensus secondary structure and the optimal sequence alignment. Despite the improved accuracy of the resulting alignment, the computational complexity of simultaneous alignment and folding for a pair of RNAs is O(N6), which is too costly to be used for large-scale analysis. RESULTS: In order to address this shortcoming, in this work, we propose a novel network-based scheme for pairwise structural alignment of RNAs. The proposed algorithm, TOPAS, builds on the concept of topological networks that provide structural maps of the RNAs to be aligned. For each RNA sequence, TOPAS first constructs a topological network based on the predicted folding structure, which consists of sequential edges and structural edges weighted by the base-pairing probabilities. The obtained networks can then be efficiently aligned by using probabilistic network alignment techniques, thereby yielding the structural alignment of the RNAs. The computational complexity of our proposed method is significantly lower than that of the Sankoff-style dynamic programming approach, while yielding favorable alignment results. Furthermore, another important advantage of the proposed algorithm is its capability of handling RNAs with pseudoknots while predicting the RNA structural alignment. We demonstrate that TOPAS generally outperforms previous RNA structural alignment methods on RNA benchmarks in terms of both speed and accuracy. AVAILABILITY AND IMPLEMENTATION: Source code of TOPAS and the benchmark data used in this paper are available at https://github.com/bjyoontamu/TOPAS.


Assuntos
Algoritmos , RNA , Alinhamento de Sequência , Pareamento de Bases , Conformação de Ácido Nucleico , Análise de Sequência de RNA
7.
BMC Bioinformatics ; 18(Suppl 14): 500, 2017 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-29297279

RESUMO

BACKGROUND: Functional modules in biological networks consist of numerous biomolecules and their complicated interactions. Recent studies have shown that biomolecules in a functional module tend to have similar interaction patterns and that such modules are often conserved across biological networks of different species. As a result, such conserved functional modules can be identified through comparative analysis of biological networks. RESULTS: In this work, we propose a novel network querying algorithm based on the CUFID (Comparative network analysis Using the steady-state network Flow to IDentify orthologous proteins) framework combined with an efficient seed-and-extension approach. The proposed algorithm, CUFID-query, can accurately detect conserved functional modules as small subnetworks in the target network that are expected to perform similar functions to the given query functional module. The CUFID framework was recently developed for probabilistic pairwise global comparison of biological networks, and it has been applied to pairwise global network alignment, where the framework was shown to yield accurate network alignment results. In the proposed CUFID-query algorithm, we adopt the CUFID framework and extend it for local network alignment, specifically to solve network querying problems. First, in the seed selection phase, the proposed method utilizes the CUFID framework to compare the query and the target networks and to predict the probabilistic node-to-node correspondence between the networks. Next, the algorithm selects and greedily extends the seed in the target network by iteratively adding nodes that have frequent interactions with other nodes in the seed network, in a way that the conductance of the extended network is maximally reduced. Finally, CUFID-query removes irrelevant nodes from the querying results based on the personalized PageRank vector for the induced network that includes the fully extended network and its neighboring nodes. CONCLUSIONS: Through extensive performance evaluation based on biological networks with known functional modules, we show that CUFID-query outperforms the existing state-of-the-art algorithms in terms of prediction accuracy and biological significance of the predictions.


Assuntos
Algoritmos , Mapeamento de Interação de Proteínas/métodos , Ferramenta de Busca , Animais , Drosophila melanogaster/genética , Humanos , Saccharomyces cerevisiae/genética , Fatores de Tempo
8.
BMC Bioinformatics ; 18(Suppl 14): 517, 2017 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-29297285

RESUMO

BACKGROUND: Piwi-interacting RNAs (piRNAs) are a new class of small non-coding RNAs that are known to be associated with RNA silencing. The piRNAs play an important role in protecting the genome from invasive transposons in the germline. Recent studies have shown that piRNAs are linked to the genome stability and a variety of human cancers. Due to their clinical importance, there is a pressing need for effective computational methods that can be used for computational identification of piRNAs. However, piRNAs lack conserved structural motifs and show relatively low sequence similarity across different species, which makes accurate computational prediction of piRNAs challenging. RESULTS: In this paper, we propose a novel method, piRNAdetect, for reliable computational prediction of piRNAs in genome sequences. In the proposed method, we first classify piRNA sequences in the training dataset that share similar sequence motifs and extract effective predictive features through the use of n-gram models (NGMs). The extracted NGM-based features are then used to construct a support vector machine that can be used for accurate prediction of novel piRNAs. CONCLUSIONS: We demonstrate the effectiveness of the proposed piRNAdetect algorithm through extensive performance evaluation based on piRNAs in three different species - H. sapiens, R. norvegicus, and M. musculus - obtained from the piRBase and show that piRNAdetect outperforms the current state-of-the-art methods in terms of efficiency and accuracy.


Assuntos
Biologia Computacional/métodos , RNA Interferente Pequeno/genética , Máquina de Vetores de Suporte , Animais , Área Sob a Curva , Bases de Dados Genéticas , Humanos , Curva ROC
9.
BMC Bioinformatics ; 17(Suppl 13): 395, 2016 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-27766938

RESUMO

BACKGROUND: Comparative analysis of protein-protein interaction (PPI) networks provides an effective means of detecting conserved functional network modules across different species. Such modules typically consist of orthologous proteins with conserved interactions, which can be exploited to computationally predict the modules through network comparison. RESULTS: In this work, we propose a novel probabilistic framework for comparing PPI networks and effectively predicting the correspondence between proteins, represented as network nodes, that belong to conserved functional modules across the given PPI networks. The basic idea is to estimate the steady-state network flow between nodes that belong to different PPI networks based on a Markov random walk model. The random walker is designed to make random moves to adjacent nodes within a PPI network as well as cross-network moves between potential orthologous nodes with high sequence similarity. Based on this Markov random walk model, we estimate the steady-state network flow - or the long-term relative frequency of the transitions that the random walker makes - between nodes in different PPI networks, which can be used as a probabilistic score measuring their potential correspondence. Subsequently, the estimated scores can be used for detecting orthologous proteins in conserved functional modules through network alignment. CONCLUSIONS: Through evaluations based on multiple real PPI networks, we demonstrate that the proposed scheme leads to improved alignment results that are biologically more meaningful at reduced computational cost, outperforming the current state-of-the-art algorithms. The source code and datasets can be downloaded from http://www.ece.tamu.edu/~bjyoon/CUFID .


Assuntos
Algoritmos , Biologia Computacional/métodos , Modelos Estatísticos , Mapas de Interação de Proteínas , Animais , Humanos , Saccharomyces cerevisiae/metabolismo
10.
BMC Bioinformatics ; 17(Suppl 13): 351, 2016 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-27766944

RESUMO

BACKGROUND: Discovering robust markers for cancer prognosis based on gene expression data is an important yet challenging problem in translational bioinformatics. By integrating additional information in biological pathways or a protein-protein interaction (PPI) network, we can find better biomarkers that lead to more accurate and reproducible prognostic predictions. In fact, recent studies have shown that, "modular markers," that integrate multiple genes with potential interactions can improve disease classification and also provide better understanding of the disease mechanisms. RESULTS: In this work, we propose a novel algorithm for finding robust and effective subnetwork markers that can accurately predict cancer prognosis. To simultaneously discover multiple synergistic subnetwork markers in a human PPI network, we build on our previous work that uses affinity propagation, an efficient clustering algorithm based on a message-passing scheme. Using affinity propagation, we identify potential subnetwork markers that consist of discriminative genes that display coherent expression patterns and whose protein products are closely located on the PPI network. Furthermore, we incorporate the topological information from the PPI network to evaluate the potential of a given set of proteins to be involved in a functional module. Primarily, we adopt widely made assumptions that densely connected subnetworks may likely be potential functional modules and that proteins that are not directly connected but interact with similar sets of other proteins may share similar functionalities. CONCLUSIONS: Incorporating topological attributes based on these assumptions can enhance the prediction of potential subnetwork markers. We evaluate the performance of the proposed subnetwork marker identification method by performing classification experiments using multiple independent breast cancer gene expression datasets and PPI networks. We show that our method leads to the discovery of robust subnetwork markers that can improve cancer classification.


Assuntos
Algoritmos , Neoplasias da Mama/metabolismo , Biologia Computacional/métodos , Mapeamento de Interação de Proteínas/métodos , Mapas de Interação de Proteínas , Neoplasias da Mama/classificação , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico
11.
BMC Bioinformatics ; 16 Suppl 13: S2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26423515

RESUMO

BACKGROUND: An accurate understanding of interactions among genes plays a major role in developing therapeutic intervention methods. Gene regulatory networks often contain a significant amount of uncertainty. The process of prioritizing biological experiments to reduce the uncertainty of gene regulatory networks is called experimental design. Under such a strategy, the experiments with high priority are suggested to be conducted first. RESULTS: The authors have already proposed an optimal experimental design method based upon the objective for modeling gene regulatory networks, such as deriving therapeutic interventions. The experimental design method utilizes the concept of mean objective cost of uncertainty (MOCU). MOCU quantifies the expected increase of cost resulting from uncertainty. The optimal experiment to be conducted first is the one which leads to the minimum expected remaining MOCU subsequent to the experiment. In the process, one must find the optimal intervention for every gene regulatory network compatible with the prior knowledge, which can be prohibitively expensive when the size of the network is large. In this paper, we propose a computationally efficient experimental design method. This method incorporates a network reduction scheme by introducing a novel cost function that takes into account the disruption in the ranking of potential experiments. We then estimate the approximate expected remaining MOCU at a lower computational cost using the reduced networks. CONCLUSIONS: Simulation results based on synthetic and real gene regulatory networks show that the proposed approximate method has close performance to that of the optimal method but at lower computational cost. The proposed approximate method also outperforms the random selection policy significantly. A MATLAB software implementing the proposed experimental design method is available at http://gsp.tamu.edu/Publications/supplementary/roozbeh15a/.


Assuntos
Redes Reguladoras de Genes/fisiologia , Genômica/métodos , Humanos , Projetos de Pesquisa , Incerteza
12.
BMC Bioinformatics ; 16 Suppl 13: S12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26423221

RESUMO

BACKGROUND: Maize, a crop of global significance, is vulnerable to a variety of biotic stresses resulting in economic losses. Fusarium verticillioides (teleomorph Gibberella moniliformis) is one of the key fungal pathogens of maize, causing ear rots and stalk rots. To better understand the genetic mechanisms involved in maize defense as well as F. verticillioides virulence, a systematic investigation of the host-pathogen interaction is needed. The aim of this study was to computationally identify potential maize subnetwork modules associated with its defense response against F. verticillioides. RESULTS: We obtained time-course RNA-seq data from B73 maize inoculated with wild type F. verticillioides and a loss-of-virulence mutant, and subsequently established a computational pipeline for network-based comparative analysis. Specifically, we first analyzed the RNA-seq data by a cointegration-correlation-expression approach, where maize genes were jointly analyzed with known F. verticillioides virulence genes to find candidate maize genes likely associated with the defense mechanism. We predicted maize co-expression networks around the selected maize candidate genes based on partial correlation, and subsequently searched for subnetwork modules that were differentially activated when inoculated with two different fungal strains. Based on our analysis pipeline, we identified four potential maize defense subnetwork modules. Two were directly associated with maize defense response and were associated with significant GO terms such as GO:0009817 (defense response to fungus) and GO:0009620 (response to fungus). The other two predicted modules were indirectly involved in the defense response, where the most significant GO terms associated with these modules were GO:0046914 (transition metal ion binding) and GO:0046686 (response to cadmium ion). CONCLUSION: Through our RNA-seq data analysis, we have shown that a network-based approach can enhance our understanding of the complicated host-pathogen interactions between maize and F. verticillioides by interpreting the transcriptome data in a system-oriented manner. We expect that the proposed analytic pipeline can also be adapted for investigating potential functional modules associated with host defense response in diverse plant-pathogen interactions.


Assuntos
Sequência de Bases/genética , Fusarium/genética , Redes Reguladoras de Genes/genética , Interações Hospedeiro-Patógeno/genética , Zea mays/genética
15.
BMC Genomics ; 15 Suppl 1: S14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24564436

RESUMO

BACKGROUND: Sequence alignment has become an indispensable tool in modern molecular biology research, and probabilistic sequence alignment models have been shown to provide an effective framework for building accurate sequence alignment tools. One such example is the pair hidden Markov model (pair-HMM), which has been especially popular in comparative sequence analysis for several reasons, including their effectiveness in modeling and detecting sequence homology, model simplicity, and the existence of efficient algorithms for applying the model to sequence alignment problems. However, despite these advantages, pair-HMMs also have a number of practical limitations that may degrade their alignment performance or render them unsuitable for certain alignment tasks. RESULTS: In this work, we propose a novel scheme for comparing and aligning biological sequences that can effectively address the shortcomings of the traditional pair-HMMs. The proposed scheme is based on a simple message-passing approach, where messages are exchanged between neighboring symbol pairs that may be potentially aligned in the optimal sequence alignment. The message-passing process yields probabilistic symbol alignment confidence scores, which may be used for predicting the optimal alignment that maximizes the expected number of correctly aligned symbol pairs. CONCLUSIONS: Extensive performance evaluation on protein alignment benchmark datasets shows that the proposed message-passing scheme clearly outperforms the traditional pair-HMM-based approach, in terms of both alignment accuracy and computational efficiency. Furthermore, the proposed scheme is numerically robust and amenable to massive parallelization.


Assuntos
Algoritmos , Alinhamento de Sequência/métodos , Benchmarking , Modelos Estatísticos , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos
16.
Biomed Eng Lett ; 14(3): 593-604, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38645588

RESUMO

Learning new motor skills is often challenged by sensory mismatches. For reliable sensory information, people have actively employed sensory intervention methods. Visual assistance is the most popular method to provide sensory information, which is equivalent to the knowledge of performance (KP) in motor tasks. However, its efficacy is questionable because of visual-proprioceptive mismatch as well as heavy intrinsic visual and cognitive engagement in motor tasks. Electrotactile intervention is a promising technique to address the current limitations, as it provides KP using tactile feedback that has a close neurophysiological association with proprioception. To test its efficacy, we compared the effects of visual and electrotactile assistance on hitting point localization of the table-tennis racket during virtual-reality table-tennis game. Experimental results suggest that location-based electrotactile feedback outperforms visual assistance in localizing the hitting point on a table-tennis racket during virtual-reality table-tennis game. Our study showed the potential of electrotactile intervention for improving the efficacy of new motor skill training.

17.
Sci Rep ; 14(1): 15237, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956095

RESUMO

Pharmacodynamic (PD) models are mathematical models of cellular reaction networks that include drug mechanisms of action. These models are useful for studying predictive therapeutic outcomes of novel drug therapies in silico. However, PD models are known to possess significant uncertainty with respect to constituent parameter data, leading to uncertainty in the model predictions. Furthermore, experimental data to calibrate these models is often limited or unavailable for novel pathways. In this study, we present a Bayesian optimal experimental design approach for improving PD model prediction accuracy. We then apply our method using simulated experimental data to account for uncertainty in hypothetical laboratory measurements. This leads to a probabilistic prediction of drug performance and a quantitative measure of which prospective laboratory experiment will optimally reduce prediction uncertainty in the PD model. The methods proposed here provide a way forward for uncertainty quantification and guided experimental design for models of novel biological pathways.


Assuntos
Teorema de Bayes , Incerteza , Modelos Biológicos , Simulação por Computador , Humanos , Transdução de Sinais
18.
Exp Clin Transplant ; 22(1): 9-16, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284370

RESUMO

OBJECTIVES: The effect of routine ureteral stenting on postoperative hydronephrosis and percutaneous ureteral intervention in kidney transplant remains unknown. This study aimed to evaluate the effects of routine ureteral stenting on hydronephrosis and percutaneous ureteral intervention and the cost benefit of ureteral stenting in kidney transplant. MATERIALS AND METHODS: We retrospectively analyzed patients who underwent kidney transplant at a tertiary institution between 2005 and 2021. We adopted a ureteral stentingprotocol in2017, anda comparisonwas performed with previous patients without stents. RESULTS: In total, 539 patients underwent kidney transplant(271 with stents [51.3%], 268 without stents [49.7%]). Hydronephrosis was detected in 16 cases (5.9%) and 30 cases (11.2%) of groups with and without stents,respectively (P = .041). Among patients with hydronephrosis, the number of patients who underwent percutaneous ureteral intervention was significantly lower in the stent group than in the nostent group (1 [6.25%] vs 10 [33.33%]; P= .014).Twenty patients (3.71%) experienced major urologic complications (19 [7.1%] in the no-stent group, and 1 [0.4%] in the stent group; P = .001). No significant differences between the groups were shown in the incidence of urinary tract infections within 3 months of transplant (24 [8.9%] vs 22 [8.2%]; P = .846). No differences were shown between the groups in ureterovesical anastomosis time (24.4 vs 24.03 min; P = .699) or 1-year graft survival (97% vs 97.8%; P = .803). The healthcare cost was significantly lower in the stent group than in the no-stent group by $1702.05 ($15000.89 vs $16702.95; P < .001). CONCLUSIONS: Routine ureteral stenting in kidney transplant significantly decreased the incidence of postoperative hydronephrosis and percutaneous ureteral intervention. Stenting did notlead to increased urinary tract infections and was cost-effective.


Assuntos
Hidronefrose , Transplante de Rim , Ureter , Obstrução Ureteral , Infecções Urinárias , Humanos , Transplante de Rim/efeitos adversos , Transplante de Rim/métodos , Estudos Retrospectivos , Ureter/cirurgia , Hidronefrose/diagnóstico , Hidronefrose/etiologia , Hidronefrose/cirurgia , Infecções Urinárias/diagnóstico , Infecções Urinárias/etiologia , Infecções Urinárias/prevenção & controle , Stents/efeitos adversos , Obstrução Ureteral/etiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia
19.
Sci Rep ; 14(1): 1181, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216607

RESUMO

Shannon entropy is a core concept in machine learning and information theory, particularly in decision tree modeling. To date, no studies have extensively and quantitatively applied Shannon entropy in a systematic way to quantify the entropy of clinical situations using diagnostic variables (true and false positives and negatives, respectively). Decision tree representations of medical decision-making tools can be generated using diagnostic variables found in literature and entropy removal can be calculated for these tools. This concept of clinical entropy removal has significant potential for further use to bring forth healthcare innovation, such as quantifying the impact of clinical guidelines and value of care and applications to Emergency Medicine scenarios where diagnostic accuracy in a limited time window is paramount. This analysis was done for 623 diagnostic tools and provided unique insights into their utility. For studies that provided detailed data on medical decision-making algorithms, bootstrapped datasets were generated from source data to perform comprehensive machine learning analysis on these algorithms and their constituent steps, which revealed a novel and thorough evaluation of medical diagnostic algorithms.


Assuntos
Algoritmos , Tomada de Decisão Clínica , Entropia , Aprendizado de Máquina , Teoria da Informação
20.
Front Bioinform ; 4: 1280971, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812660

RESUMO

Radiation exposure poses a significant threat to human health. Emerging research indicates that even low-dose radiation once believed to be safe, may have harmful effects. This perception has spurred a growing interest in investigating the potential risks associated with low-dose radiation exposure across various scenarios. To comprehensively explore the health consequences of low-dose radiation, our study employs a robust statistical framework that examines whether specific groups of genes, belonging to known pathways, exhibit coordinated expression patterns that align with the radiation levels. Notably, our findings reveal the existence of intricate yet consistent signatures that reflect the molecular response to radiation exposure, distinguishing between low-dose and high-dose radiation. Moreover, we leverage a pathway-constrained variational autoencoder to capture the nonlinear interactions within gene expression data. By comparing these two analytical approaches, our study aims to gain valuable insights into the impact of low-dose radiation on gene expression patterns, identify pathways that are differentially affected, and harness the potential of machine learning to uncover hidden activity within biological networks. This comparative analysis contributes to a deeper understanding of the molecular consequences of low-dose radiation exposure.

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