21 research outputs found

    A Bayesian Logistic Regression approach in Asthma Persistence Prediction

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    Background: A number of models based on clinical parameters have been used for the prediction of asthma persistence in children. The number and significance of factors that are used in a proposed model play a cardinal role in prediction accuracy. Different models may lead to different significant variables. In addition, the accuracy of a model in medicine is really important since an accurate prediction of illness persistence may improve prevention and treatment intervention for the children at risk. Methods: Data from 147 asthmatic children were analyzed by a new method for predicting asthma outcome using Principal Component Analysis (PCA) in combination with a Bayesian logistic regression approach implemented by the Markov Chain Monte Carlo (MCMC). The use of PCA is required due to multicollinearity among the explanatory variables. Results: This method using the most appropriate models seems to predict asthma with an accuracy of 84.076% and 86.3673%, a Sensitivity of 84.96% and 87.25% and a Specificity of 83.22% and 85.52%, respectively. Conclusion: Our approach predicts asthma with high accuracy, gives steadier results in terms of positive and negative patients and provides better information about the influence of each factor (demographic, symptoms etc.) in asthma prediction

    CT Characteristics of Pheochromocytoma: Relevance for the Evaluation of Adrenal Incidentaloma.

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    BACKGROUND: Up to 7% of all adrenal incidentalomas (AIs) are pheochromocytomas (PCCs). In the evaluation of AI, it is generally recommended that PCC be excluded by measurement of plasma-free or 24-hour urinary fractionated metanephrines. However, recent studies suggest that biochemical exclusion of PCC not be performed for lesions with CT characteristics of an adrenocortical adenoma (ACA). AIM: To determine the proportion of PCCs with ACA-like attenuation or contrast washout on CT. METHODS: For this multicenter retrospective study, two central investigators independently analyzed the CT reports of 533 patients with 548 histologically confirmed PCCs. Data on tumor size, unenhanced Hounsfield units (HU), absolute percentage washout (APW), and relative percentage washout (RPW) were collected in addition to clinical parameters. RESULTS: Among the 376 PCCs for which unenhanced attenuation data were available, 374 had an attenuation of >10 HU (99.5%). In the two exceptions (0.5%), unenhanced attenuation was exactly 10 HU, which lies just within the range of ≤10 HU that would suggest a diagnosis of ACA. Of 76 PCCs with unenhanced HU > 10 and available washout data, 22 (28.9%) had a high APW and/or RPW, suggestive of ACA. CONCLUSION: Based on the lack of PCCs with an unenhanced attenuation of <10 HU and the low proportion (0.5%) of PCCs with an attenuation of 10 HU, it seems reasonable to abstain from biochemical testing for PCC in AIs with an unenhanced attenuation of ≤10 HU. The assessment of contrast washout, however, is unreliable for ruling out PCC

    Age-dependent and sex-dependent disparity in mortality in patients with adrenal incidentalomas and autonomous cortisol secretion: an international, retrospective, cohort study

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    Background: The association between cortisol secretion and mortality in patients with adrenal incidentalomas is controversial. We aimed to assess all-cause mortality, prevalence of comorbidities, and occurrence of cardiovascular events in uniformly stratified patients with adrenal incidentalomas and cortisol autonomy (defined as non-suppressible serum cortisol on dexamethasone suppression testing). Methods: We conducted an international, retrospective, cohort study (NAPACA Outcome) at 30 centres in 16 countries. Eligible patients were aged 18 years or older with an adrenal incidentaloma (diameter ≥1 cm) detected between Jan 1, 1996, and Dec 31, 2015, and availability of a 1 mg dexamethasone suppression test result from the time of the initial diagnosis. Patients with clinically apparent hormone excess, active malignancy, or follow-up of less than 36 months were excluded. Patients were stratified according to the 0800–0900 h serum cortisol values after an overnight 1 mg dexamethasone suppression test; less than 50 nmol/L was classed as non-functioning adenoma, 50–138 nmol/L as possible autonomous cortisol secretion, and greater than 138 nmol/L as autonomous cortisol secretion. The primary endpoint was all-cause mortality. Secondary endpoints were the prevalence of cardiometabolic comorbidities, cardiovascular events, and cause-specific mortality. The primary and secondary endpoints were assessed in all study participants. Findings: Of 4374 potentially eligible patients, 3656 (2089 [57·1%] with non-functioning adenoma, 1320 [36·1%] with possible autonomous cortisol secretion, and 247 [6·8%] with autonomous cortisol secretion) were included in the study cohort for mortality analysis (2350 [64·3%] women and 1306 [35·7%] men; median age 61 years [IQR 53–68]; median follow-up 7·0 years [IQR 4·7–10·2]). During follow-up, 352 (9·6%) patients died. All-cause mortality (adjusted for age, sex, comorbidities, and previous cardiovascular events) was significantly increased in patients with possible autonomous cortisol secretion (HR 1·52, 95% CI 1·19–1·94) and autonomous cortisol secretion (1·77, 1·20–2·62) compared with patients with non-functioning adenoma. In women younger than 65 years, autonomous cortisol secretion was associated with higher all-cause mortality than non-functioning adenoma (HR 4·39, 95% CI 1·93–9·96), although this was not observed in men. Cardiometabolic comorbidities were significantly less frequent with non-functioning adenoma than with possible autonomous cortisol secretion and autonomous cortisol secretion (hypertension occurred in 1186 [58·6%] of 2024 patients with non-functioning adenoma, 944 [74·0%] of 1275 with possible autonomous cortisol secretion, and 179 [75·2%] of 238 with autonomous cortisol secretion; dyslipidaemia occurred in 724 [36·2%] of 1999 patients, 547 [43·8%] of 1250, and 123 [51·9%] of 237; and any diabetes occurred in 365 [18·2%] of 2002, 288 [23·0%] of 1250, and 62 [26·7%] of 232; all p values &lt;0·001). Interpretation: Cortisol autonomy is associated with increased all-cause mortality, particularly in women younger than 65 years. However, until results from randomised interventional trials are available, a conservative therapeutic approach seems to be justified in most patients with adrenal incidentaloma. Funding: Deutsche Forschungsgemeinschaft, Associazione Italiana per la Ricerca sul Cancro, Università di Torino

    Where are we now with European forest multi-taxon biodiversity and where can we head to?

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    The European biodiversity and forest strategies rely on forest sustainable management (SFM) to conserve forest biodiversity. However, current sustainability assessments hardly account for direct biodiversity indicators. We focused on forest multi-taxon biodiversity to: i) gather and map the existing information; ii) identify knowledge and research gaps; iii) discuss its research potential. We established a research network to fit data on species, standing trees, lying deadwood and sampling unit description from 34 local datasets across 3591 sampling units. A total of 8724 species were represented, with the share of common and rare species varying across taxonomic classes: some included many species with several rare ones (e.g., Insecta); others (e.g., Bryopsida) were represented by few common species. Tree-related structural attributes were sampled in a subset of sampling units (2889; 2356; 2309 and 1388 respectively for diameter, height, deadwood and microhabitats). Overall, multi-taxon studies are biased towards mature forests and may underrepresent the species related to other developmental phases. European forest compositional categories were all represented, but beech forests were over-represented as compared to thermophilous and boreal forests. Most sampling units (94%) were referred to a habitat type of conservation concern. Existing information may support European conservation and SFM strategies in: (i) methodological harmonization and coordinated monitoring; (ii) definition and testing of SFM indicators and thresholds; (iii) data-driven assessment of the effects of environmental and management drivers on multi-taxon forest biological and functional diversity, (iv) multi-scale forest monitoring integrating in-situ and remotely sensed information

    Urine steroid metabolomics for the differential diagnosis of adrenal incidentalomas in the EURINE-ACT study: a prospective test validation study

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    Transcriptomics, epigenetics, and metabolomics of primary aldosteronism

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    Introduction: Primary aldosteronism (PA) is the most common cause of endocrine hypertension, mainly caused by aldosterone‐producing adenomas or hyperplasia; understanding its pathophysiological background is important in order to provide ameliorative treatment strategies. Over the past several years, significant progress has been documented in this field, in particular in the clarification of the genetic and molecular mechanisms responsible for the pathogenesis of aldosterone‐producing adenomas (APAs). Methods: Systematic searches of the PubMed and Cochrane databases were performed for all human studies applying transcriptomic, epigenetic or metabolomic analyses to PA subjects. Studies involving serial analysis of gene expression and microarray, epigenetic studies with methylome analyses and micro‐RNA expression profiles, and metabolomic studies focused on improving understanding of the regulation of autonomous aldosterone production in PA were all included. Results: In this review we summarize the main findings in this area and analyze the interplay between primary aldosteronism and several signaling pathways with differential regulation of the RNA and protein expression of several factors involved in, among others, steroidogenesis, calcium signaling, and nuclear, membrane and G‐coupled protein receptors. Distinct transcriptomic and metabolomic patterns are also presented herein, depending on the mutational status of APAs. In particular, two partially opposite transcriptional and steroidogenic profiles appear to distinguish APAs carrying a KCNJ5 mutation from all other APAs, which carry different mutations. Conclusions: These findings can substantially contribute to the development of personalized treatment in patients with PA. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

    Evaluation of Bayesian classifiers in asthma exacerbation prediction after medication discontinuation

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    Abstract Objective The achievement of the optimal control of the disease is of cardinal importance in asthma treatment. As the control of the disease is sustained the medication should be gradually reduced and then stopped. Nevertheless, the discontinuation of asthma medication may lead to loss of disease control and eventually to an exacerbation of the disease. The goal of this paper is to examine the performance of Bayesian network classifiers in predicting asthma exacerbation based on several patient’s parameters such as objective measurements and medical history data. Results In this study several Bayesian network classifiers are presented and evaluated. It is shown that the proposed semi-naive network classifier with the use of Backward Sequential Elimination and Joining algorithm is able to predict if a patient will have an exacerbation of the disease after his last assessment with 93.84% accuracy and 90.9% sensitivity. In addition, the resulting structure and the conditional probability tables give a clear view of the probabilistic relationships between the used factors. This network may help the clinicians to identify the patients who are at high risk of having an exacerbation after stopping the medication and to confirm which factors are the most important

    The sun as a significant agent provoking earthquakes

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    In this paper we provide significant evidence that the sun is a principal agent provoking seismic activity. In particular the aim of the studies presented is to examine the possible relation of the coronal hole (CH) driven high speed solar wind streams (HSSs) with seismicity We performed several statistical studies of solar space and seismological data between 1980 and 2017 as well as a study for a long time interval from the year 1900 until the year 2017. (A1) Concerning the period 1980–2017 among other results we found that the earthquakes (EQs) with M ≥ 83 between 2010–2017 (including the catastrophic earthquakes of Japan 2011 (M91) Sumatra 2012 (M86) and Chile 2015 (M83)) occurred during times of large coronal holes as seen by the Solar Dynamics Observatory (SDO) satellite and were related with CH-driven HSSs observed by the ACE spacecraft several weeks or a few months before the EQ occurrences. (A2) Further research on the hypothesis of the possible HSS-EQ relationship revealed a surprising novel finding: a power spectrum analysis suggests that during the decay phase of the SCC22 and SC23 and at the maximum of SC23 the values of the global seismic (M ≥ 6) energy output shows a periodic variation of ~27 days, which is the mean rotational period of the Sun. (A3) Moderate (not strong) storms in general precede the great EQs. (B) The study of the data for the time interval 1900–2017 revealed that: (1) all of the giant (M ≥ 85) EQs occurred during the decay minimum and the rising phase of the solar cycle or in the maximum phase but at times of a strong reduction of the monthly averaged sunspot number: Chile M95 1960 EQ – Alaska M92 1964 EQ – Sumatra M91 2004 EQ (decay phase) Japan M91 2011 EQ (rising phase of the &quot;strange&quot; SC24) (2) the global energy release of all EQs with magnitudes M ≥ 55 show the highest values during the decay phase of the solar cycle and in particular three years after the solar maximum and (3) a very significant negative correlation (rS = −042p &amp;lt; 10−4) was found between the SSN and the number of earthquakes with M ≥ 7 during the period 1930–2010 during times of moderate and high amplitude solar cycles. (C) Another result of our study is that the comparison of the yearly numbers of great (M ≥ 7) EQs with the SSN fails to provide correct statistical results whereas this is possible for the global seismic energy or the giant EQs. (D) Finally we infer that the case and statistical studies presented in this paper strongly suggest a close relation between CH-associated HSSs and seismic activity. We present some observational evidence that most probably Alfvèn waves mediate the interaction of CH-driven HSSs with seismicity. © 2021, The Author(s)

    Mixed Models as a Tool for Comparing Groups of Time Series in Plant Sciences

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    Plants adapt to continual changes in environmental conditions throughout their life spans. High-throughput phenotyping methods have been developed to noninvasively monitor the physiological responses to abiotic/biotic stresses on a scale spanning a long time, covering most of the vegetative and reproductive stages. However, some of the physiological events comprise almost immediate and very fast responses towards the changing environment which might be overlooked in long-term observations. Additionally, there are certain technical difficulties and restrictions in analyzing phenotyping data, especially when dealing with repeated measurements. In this study, a method for comparing means at different time points using generalized linear mixed models combined with classical time series models is presented. As an example, we use multiple chlorophyll time series measurements from different genotypes. The use of additional time series models as random effects is essential as the residuals of the initial mixed model may contain autocorrelations that bias the result. The nature of mixed models offers a viable solution as these can incorporate time series models for residuals as random effects. The results from analyzing chlorophyll content time series show that the autocorrelation is successfully eliminated from the residuals and incorporated into the final model. This allows the use of statistical inference
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