Kristina Časni

Mrs. Kristina Časni

Know Center, Graz, Steiermark, Austria
orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 April 2021 in Environmental Pollution
Verified
Journal Article
Closed access
Mario LovrićMario Lovrić
Mario Lovrić
KČKristina Časni
Kristina Časni
Matej VukovicMatej Vukovic
Matej Vukovic
SGStuart K. Grange
Stuart K. Grange
MHMichael Haberl
Michael Haberl
Roman KernRoman Kern
Roman Kern

7 May 2021 in Journal of Chemometrics
Verified
Journal Article
Open access
PDF file
Mario LovrićMario Lovrić
Mario Lovrić
KČKristina Časni
Kristina Časni
PZPetar Zuvela
Petar Zuvela
ASAdrian Spataru
Adrian Spataru
Bono LucicBono Lucic
Bono Lucic
Ming Wah WongMing Wah Wong
Ming Wah Wong
We present a collection of publicly available intrinsic aqueous solubility data of 829 drug‐like compounds. Four different machine learning algorithms (random forests [RF], LightGBM, partial least squares, and least absolute shrinkage and selection operator [LASSO]) coupled with multistage permutation importance for feature selection and Bayesian hyperparameter optimization were used for the prediction of solubility based on chemical structural information. Our results show that LASSO yielded the best predictive ability on an external test set with a root mean square error (RMSE) (test) of 0.70 log points, anR2(test) of 0.80, and 105 features. Taking into account the number of descriptors as well, an RF model achieves the best balance between complexity and predictive ability with an RMSE(test) of 0.72 log points, anR2(test) of 0.78, and with only 17 features. On a more aggressive test set (principal component analysis [PCA]‐based split), better generalization was observed for the RF model. We propose a ranking score for choosing the best model, as test set performance is only one of the factors in creating an applicable model. The ranking score is a weighted combination of generalization, number of features, and test performance. Out of the two best learners, a consensus model was built exhibiting the best predictive ability and generalization with RMSE(test) of 0.67 log points and aR2(test) of 0.81.

10 May 2021 in Children
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Journal Article
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Mario LovrićMario Lovrić
Mario Lovrić
IBIvana Banic
Ivana Banic
ELEmanuel Lacic
Emanuel Lacic
KČKristina Časni
Kristina Časni
Roman KernRoman Kern
Roman Kern
MTMirjana Turkalj
Mirjana Turkalj
Asthma in children is a heterogeneous disease manifested by various phenotypes and endotypes. The level of disease control, as well as the effectiveness of anti-inflammatory treatment, is variable and inadequate in a significant portion of patients. By applying machine learning algorithms, we aimed to predict the treatment success in a pediatric asthma cohort and to identify the key variables for understanding the underlying mechanisms. We predicted the treatment outcomes in children with mild to severe asthma (N = 365), according to changes in asthma control, lung function (FEV1 and MEF50) and FENO values after 6 months of controller medication use, using Random Forest and AdaBoost classifiers. The highest prediction power is achieved for control- and, to a lower extent, for FENO-related treatment outcomes, especially in younger children. The most predictive variables for asthma control are related to asthma severity and the total IgE, which were also predictive for FENO-based outcomes. MEF50-related treatment outcomes were better predicted than the FEV1-based response, and one of the best predictive variables for this response was hsCRP, emphasizing the involvement of the distal airways in childhood asthma. Our results suggest that asthma control- and FENO-based outcomes can be more accurately predicted using machine learning than the outcomes according to FEV1 and MEF50. This supports the symptom control-based asthma management approach and its complementary FENO-guided tool in children. T2-high asthma seemed to respond best to the anti-inflammatory treatment. The results of this study in predicting the treatment success will help to enable treatment optimization and to implement the concept of precision medicine in pediatric asthma treatment.

4 August 2020 in ChemRxiv
Verified
Preprint
Open access
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Mario LovrićMario Lovrić
Mario Lovrić
KČKristina Časni
Kristina Časni
PZPetar Zuvela
Petar Zuvela
ASAdrian Spataru
Adrian Spataru
Bono LucicBono Lucic
Bono Lucic
Ming Wah WongMing Wah Wong
Ming Wah Wong
Here, we present a collection of publicly availableintrinsic aqueous solubility data of 829 drug-likecompounds. Four different machine learning algorithms(random forest, light GBM, partial least squares andLASSO) coupled with multi-stage permutationimportance for feature selection and Bayesian hyperparameter optimization were employed for theprediction of solubility based on chemical structuralinformation. Our results have shown that LASSOyielded the best predictive ability on an external test setwith and RMSE(test) of 0.70 log points and 105 featuresin the model. Taking into account the number ofdescriptors as well, an RF model achieved the bestbalance between complexity and predictive ability withan RMSE(test) of 0.72 with only 17 features. Wepropose a ranking score for choosing the best model, astest set performance is only one of the factors in creatingan applicable model. The ranking score is a weightedcombination of generalization, number of featuresinvolved and test set performance The data related to this paper can be downloaded from 10.5281/zenodo.3968754

10 May 2024 in Metabolites
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Journal Article
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Mario LovrićMario Lovrić
Mario Lovrić
TWTingting Wang
Tingting Wang
MSMads Staffe
Mads Staffe
IŠIva Šunić
Iva Šunić
KČKristina Časni
Kristina Časni
MRMorten Arendt Rasmussen
Morten Arendt Rasmussen
Metabolomics has gained much attention due to its potential to reveal molecular disease mechanisms and present viable biomarkers. This work uses a panel of untargeted serum metabolomes from 602 children from the COPSAC2010 mother–child cohort. The annotated part of the metabolome consists of 517 chemical compounds curated using automated procedures. We created a filtering method for the quantified metabolites using predicted quantitative structure–bioactivity relationships for the Tox21 database on nuclear receptors and stress response in cell lines. The metabolites measured in the children’s serums are predicted to affect specific targeted models, known for their significance in inflammation, immune function, and health outcomes. The targets from Tox21 have been used as targets with quantitative structure–activity relationships (QSARs). They were trained for ~7000 structures, saved as models, and then applied to the annotated metabolites to predict their potential bioactivities. The models were selected based on strict accuracy criteria surpassing random effects. After application, 52 metabolites showed potential bioactivity based on structural similarity with known active compounds from the Tox21 set. The filtered compounds were subsequently used and weighted by their bioactive potential to show an association with early childhood hs-CRP levels at six months in a linear model supporting a physiological adverse effect on systemic low-grade inflammation.

14 August 2020 in ChemRxiv
Verified
Preprint
Open access
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Mario LovrićMario Lovrić
Mario Lovrić
KČKristina Časni
Kristina Časni
Matej VukovicMatej Vukovic
Matej Vukovic
SGStuart K. Grange
Stuart K. Grange
MHMichael Haberl
Michael Haberl
Roman KernRoman Kern
Roman Kern
During March, 2020, most European countries implemented lockdowns to restrict the transmission of SARS-CoV-2, the virus which causes COVID-19 through their populations. These restrictions had positive impacts for air quality due to a dramatic reduction of economic activity and emissions. In this work, a machine learning approach was designed and implemented to analyze local air quality improvements during the COVID-19 lockdown in Graz, Austria. The machine learning approach was used as a robust alternative to simple, historical measurement comparisons for various individual pollutants. Concentrations of NO2 (nitrogen dioxide), PM10, O3 (ozone) and Ox (total oxidant) were selected from five measurement sites in Graz and were set as target variables for random forest regression models to predict their expected values during the city's lockdown period. The true vs. expected difference is presented here as an indicator of true pollution during the lockdown. The machine learning models showed a high level of generalization for predicting the concentrations. Therefore, the approach was suitable for analyzing reductions in pollution concentrations. Results on the validation set showed very good performance for Ox and NO2 when compared to PM10 and O3. The analysis indicated that the city’s average concentration reductions for the lockdown period were: -36.9 to -41.6%, and -6.6 to -14.2% for NO2 and PM10, respectively. However, an increase of 11.6 to 33.8% for O3 was estimated. The reduction in pollutant concentration, especially NO2 can be explained by significant drops in traffic-flows during the lockdown period (-51.6 to -43.9%). The results presented give a real-world example of what pollutant concentration reductions can be achieved by reducing traffic-flows and other economic activities.