156 research outputs found
Explainable machine learning-based prediction model for diabetic nephropathy
The aim of this study is to analyze the effect of serum metabolites on
diabetic nephropathy (DN) and predict the prevalence of DN through a machine
learning approach. The dataset consists of 548 patients from April 2018 to
April 2019 in Second Affiliated Hospital of Dalian Medical University (SAHDMU).
We select the optimal 38 features through a Least absolute shrinkage and
selection operator (LASSO) regression model and a 10-fold cross-validation. We
compare four machine learning algorithms, including eXtreme Gradient Boosting
(XGB), random forest, decision tree and logistic regression, by AUC-ROC curves,
decision curves, calibration curves. We quantify feature importance and
interaction effects in the optimal predictive model by Shapley Additive
exPlanations (SHAP) method. The XGB model has the best performance to screen
for DN with the highest AUC value of 0.966. The XGB model also gains more
clinical net benefits than others and the fitting degree is better. In
addition, there are significant interactions between serum metabolites and
duration of diabetes. We develop a predictive model by XGB algorithm to screen
for DN. C2, C5DC, Tyr, Ser, Met, C24, C4DC, and Cys have great contribution in
the model, and can possibly be biomarkers for DN
Reversible and time-dependent inhibition of CYP3A4-mediated nifedipine oxidation by noscapine
Substrate-dependent inhibition of CYP3A4 might influence the extrapolation of drug interactions from the in vitro to in vivo situation. The aim of the present study is to investigate reversible and time-dependent inhibition of CYP3A4-mediated nifedipine oxidation by noscapine. Furthermore, in vitroin vivo extrapolation (IVIVE) was performed using in vitro parameters. The results showed that CYP3A4- mediated nifedipine oxidation activity was strongly inhibited with an IC50 of 25.7 ± 5.4 μM. Kinetic analysis showed that inhibition of CYP3A4-mediated nifedipine oxidation by noscapine was best fit to a noncompetitive manner with Ki value of 10.9 μM. IC50 shift experiment showed that IC50 was significantly decreased from 25.7 ± 5.4 μM to 0.34 ± 0.07 μM after pre-incubation with noscapine for 30 min, which indicated that time-dependent inhibition existed for inhibition of CYP3A4 by noscapine. The AUC of (R)- warfarin was predicted to increase by 0.5 % using Cmax or 0.2 % using unbound Cmax with reversible inhibition prediction equation, while the AUC of (R)-warfarin was estimated to increase by 23.1 % using Cmax or 10.4 % using unbound Cmax with TDI prediction equation. Inhibition of CYP3A4 by noscapine showed substrate-dependent inhibition behaviour. However, the results obtained from IVIVE are very similar using testosterone or nifedipine as probe substrates.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Decision Forest Analysis of 61 Single Nucleotide Polymorphisms in a Case-Control Study of Esophageal Cancer; a novel method
BACKGROUND: Systematic evaluation and study of single nucleotide polymorphisms (SNPs) made possible by high throughput genotyping technologies and bioinformatics promises to provide breakthroughs in the understanding of complex diseases. Understanding how the millions of SNPs in the human genome are involved in conferring susceptibility or resistance to disease, or in rendering a drug efficacious or toxic in the individual is a major goal of the relatively new fields of pharmacogenomics. Esophageal squamous cell carcinoma is a high-mortality cancer with complex etiology and progression involving both genetic and environmental factors. We examined the association between esophageal cancer risk and patterns of 61 SNPs in a case-control study for a population from Shanxi Province in North Central China that has among the highest rates of esophageal squamous cell carcinoma in the world. METHODS: High-throughput Masscode mass spectrometry genotyping was done on genomic DNA from 574 individuals (394 cases and 180 age-frequency matched controls). SNPs were chosen from among genes involving DNA repair enzymes, and Phase I and Phase II enzymes. We developed a novel adaptation of the Decision Forest pattern recognition method named Decision Forest for SNPs (DF-SNPs). The method was designated to analyze the SNP data. RESULTS: The classifier in separating the cases from the controls developed with DF-SNPs gave concordance, sensitivity and specificity, of 94.7%, 99.0% and 85.1%, respectively; suggesting its usefulness for hypothesizing what SNPs or combinations of SNPs could be involved in susceptibility to esophageal cancer. Importantly, the DF-SNPs algorithm incorporated a randomization test for assessing the relevance (or importance) of individual SNPs, SNP types (Homozygous common, heterozygous and homozygous variant) and patterns of SNP types (SNP patterns) that differentiate cases from controls. For example, we found that the different genotypes of SNP GADD45B E1122 are all associated with cancer risk. CONCLUSION: The DF-SNPs method can be used to differentiate esophageal squamous cell carcinoma cases from controls based on individual SNPs, SNP types and SNP patterns. The method could be useful to identify potential biomarkers from the SNP data and complement existing methods for genotype analyses
A universal programmable Gaussian Boson Sampler for drug discovery
Gaussian Boson Sampling (GBS) exhibits a unique ability to solve graph
problems, such as finding cliques in complex graphs. It is noteworthy that many
drug discovery tasks can be viewed as the clique-finding process, making them
potentially suitable for quantum computation. However, to perform these tasks
in their quantum-enhanced form, a large-scale quantum hardware with universal
programmability is essential, which is yet to be achieved even with the most
advanced GBS devices. Here, we construct a time-bin encoded GBS photonic
quantum processor that is universal, programmable, and software-scalable. Our
processor features freely adjustable squeezing parameters and can implement
arbitrary unitary operations with a programmable interferometer. Using our
processor, we have demonstrated the clique-finding task in a 32-node graph,
where we found the maximum weighted clique with approximately twice the
probability of success compared to classical sampling. Furthermore, a
multifunctional quantum pharmaceutical platform is developed. This GBS
processor is successfully used to execute two different drug discovery methods,
namely molecular docking and RNA folding prediction. Our work achieves the
state-of-the-art in GBS circuitry with its distinctive universal and
programmable architecture which advances GBS towards real-world applications.Comment: 10 pages, 5 figure
The Survey of H5N1 Flu Virus in Wild Birds in 14 Provinces of China from 2004 to 2007
The highly pathogenic H5N1 avian influenza emerged in the year 1996 in Asia, and has spread to Europe and Africa recently. At present, effective monitoring and data analysis of H5N1 are not sufficient in Chinese mainland.)) were obviously higher than those in other 13 provinces. The results of sequence analysis indicated that the 17 strains isolated from wild birds were distributed in five clades (2.3.1, 2.2, 2.5, 6, and 7), which suggested that genetic diversity existed among H5N1 viruses isolated from wild birds. The five isolates from Qinghai came from one clade (2.2) and had a short evolutionary distance with the isolates obtained from Qinghai in the year 2005.We have measured the prevalence of H5N1 virus in 56 species of wild birds in 14 provinces of China. Continuous monitoring in the field should be carried out to know whether H5N1 virus can be maintained by wild birds
Integrative genomics analysis of genes with biallelic loss and its relation to the expression of mRNA and micro-RNA in esophageal squamous cell carcinoma
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
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Joint analysis of three genome-wide association studies of esophageal squamous cell carcinoma in Chinese populations
We conducted a joint (pooled) analysis of three genome-wide association studies (GWAS) 1-3 of esophageal squamous cell carcinoma (ESCC) in ethnic Chinese (5,337 ESCC cases and 5,787 controls) with 9,654 ESCC cases and 10,058 controls for follow-up. In a logistic regression model adjusted for age, sex, study, and two eigenvectors, two new loci achieved genome-wide significance, marked by rs7447927 at 5q31.2 (per-allele odds ratio (OR) = 0.85, 95% CI 0.82-0.88; P=7.72x10−20) and rs1642764 at 17p13.1 (per-allele OR= 0.88, 95% CI 0.85-0.91; P=3.10x10−13). rs7447927 is a synonymous single nucleotide polymorphism (SNP) in TMEM173 and rs1642764 is an intronic SNP in ATP1B2, near TP53. Furthermore, a locus in the HLA class II region at 6p21.32 (rs35597309) achieved genome-wide significance in the two populations at highest risk for ESSC (OR=1.33, 95% CI 1.22-1.46; P=1.99x10−10). Our joint analysis identified new ESCC susceptibility loci overall as well as a new locus unique to the ESCC high risk Taihang Mountain region
Female chromosome X mosaicism is age-related and preferentially affects the inactivated X chromosome
To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events >2 Mb in 97 (0.25%) women. Here we show rates for X-chromosome mosaicism are four times higher than mean autosomal rates; X mosaic events more often include the entire chromosome and participants with X events more likely harbour autosomal mosaic events. X mosaicism frequency increases with age (0.11% in 50-year olds; 0.45% in 75-year olds), as reported for Y and autosomes. Methylation array analyses of 33 women with X mosaicism indicate events preferentially involve the inactive X chromosome. Our results provide further evidence that the sex chromosomes undergo mosaic events more frequently than autosomes, which could have implications for understanding the underlying mechanisms of mosaic events and their possible contribution to risk for chronic diseases
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