Improving ED Emergency Severity Index Acuity Assignment Using Machine Learning and Clinical Natural Language Processing.

INTRODUCTION: Triage is critical to mitigating the effect of increased volume by determining patient acuity, need for resources, and establishing acuity-based patient prioritization. The purpose of this retrospective study was to determine whether historical EHR data can be used with clinical natural language processing and machine learning algorithms (KATE) to produce accurate ESI predictive models. METHODS: The KATE triage model was developed using 166,175 patient encounters from two participating hospitals. The model was tested against a random sample of encounters that were correctly assigned an acuity by study clinicians using the Emergency Severity Index (ESI) standard as a guide. RESULTS: At the study sites, KATE predicted accurate ESI acuity assignments 75.7% of the time compared with nurses (59.8%) and the average of individual study clinicians (75.3%). KATE's accuracy was 26.9% higher than the average nurse accuracy (P <.001). On the boundary between ESI 2 and ESI 3 acuity assignments, which relates to the risk of decompensation, KATE's accuracy was 93.2% higher, with 80% accuracy compared with triage nurses 41.4% accuracy (P <.001). DISCUSSION: KATE provides a triage acuity assignment more accurate than the triage nurses in this study sample. KATE operates independently of contextual factors, unaffected by the external pressures that can cause under triage and may mitigate biases that can negatively affect triage accuracy. Future research should focus on the impact of KATE providing feedback to triage nurses in real time, on mortality and morbidity, ED throughput, resource optimization, and nursing outcomes.

Microbiological aspects of conservative treatment of periodontal disease using gel-based preparations.

The results of epidemiological studies as well as statistical data show that in recent years the dental morbidity rate in the world has remained stable at a high level. Inflammatory diseases of periodontal tissues, in particular generalized forms of periodontitis, reach 80% in the world. The tendency of increasing the prevalence rate of these diseases in Ukraine, 60-99%, is being observed nowadays. AIM: The aim of this study was to examine the antimicrobial activity of three gel-based medicinal products, being widely used in periodontology: Abigel, an herbal remedy, containing fir oil and oak bark extract; Fitoron, which contains oak bark extract, and President gel with chlorhexidine. MATERIALS AND METHODS: Gram-positive and gram-negative bacteria, belonging to different taxonomic groups: Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Bacillus subtilis ATCC 6633 and Proteus vulgaris ATCC 4636, Candida albicans ATCC 885-653, were as a substrate for further examinations. Preparing the suspensions of microorganisms with a defined optical density of microbial cells was executed using the turbidity standard (0.5 McFarland standard). The Densi-La-Meter device (made by "PLIVA-Lachema", Czech Republic; wavelength = 540 nm) was used. The suspension was prepared in accordance with the device guidance and the information sheet on innovations in the health care system No. 163-2006 "Standardization of preparation of microbial suspensions". RESULTS: The highest activity against Staphylococcus aureus is being observed in President gel with chlorhexidine (24 mm and 25 mm), followed by Abigel gel (20, 21, 22 mm) and Fitoron has the minimum activity (17 and 18 mm). The growth zone of Bacillus subtilis is maximally inhibited by President gel with chlorhexidine (25 and 26 mm), Fitoron's inhibition zone is of 23 and 24 mm, and in the last place is Abigel gel - 20 and 21 mm. President gel with chlorhexidine has a pronounced antifungal effect with the inhibition zone of 20, 21 and 22 mm, Fitoron's inhibition zone is of 19 and 20 mm, and one of Abigel gel - of 16 and 17 mm. Concerning Enterococcus faecalis, the highest activity was established in President gel with chlorhexidine (the inhibition zone of 22 and 23 mm), Abigel gel had inhibition zone of 20 and 21 mm, whereas one of Fitoron was of 18 and 19 mm. Haemophilus influenzae was maximally influenced by President gel with chlorhexidine with the inhibition zone of 19 and 20 mm, Abigel gel caused the growth inhibition by 17 and 18 mm, and the lowest growth inhibition was of Fitoron - 16 mm. President gel with chlorhexidine (19, 20, 21 mm) and Abigel gel (19 mm) had almost the same influence on the growth of Streptococcus pyogenes, whereas these figures of Fitoron were 16 and 17 mm. Abigel gel had a pronounced activity against Streptococcus mutans with the inhibition zone of 20 mm, one of President gel with chlorhexidine was of 19 and 20 mm, and of Fitoron - 17 and 18 mm. The growth of Neisseria sp was maximally inhibited by President gel with chlorhexidine (18, 19, 20 mm), in the second place was Abigel gel (18, 19 mm) and the lowest results were of Fitoron (16, 17 mm). CONCLUSIONS: President gel with chlorhexidine, Fitoron and Abigel gel have pronounced antimicrobial properties as to the testing cultures of microorganisms under study. Abigel is an effective method of choice in the conservative treatment of inflammatory periodontal diseases.

Steady states and stability in metabolic networks without regulation.

Metabolic networks are often extremely complex. Despite intensive efforts many details of these networks, e.g., exact kinetic rates and parameters of metabolic reactions, are not known, making it difficult to derive their properties. Considerable effort has been made to develop theory about properties of steady states in metabolic networks that are valid for any values of parameters. General results on uniqueness of steady states and their stability have been derived with specific assumptions on reaction kinetics, stoichiometry and network topology. For example, deep results have been obtained under the assumptions of mass-action reaction kinetics, continuous flow stirred tank reactors (CFSTR), concordant reaction networks and others. Nevertheless, a general theory about properties of steady states in metabolic networks is still missing. Here we make a step further in the quest for such a theory. Specifically, we study properties of steady states in metabolic networks with monotonic kinetics in relation to their stoichiometry (simple and general) and the number of metabolites participating in every reaction (single or many). Our approach is based on the investigation of properties of the Jacobian matrix. We show that stoichiometry, network topology, and the number of metabolites that participate in every reaction have a large influence on the number of steady states and their stability in metabolic networks. Specifically, metabolic networks with single-substrate-single-product reactions have disconnected steady states, whereas in metabolic networks with multiple-substrates-multiple-product reactions manifolds of steady states arise. Metabolic networks with simple stoichiometry have either a unique globally asymptotically stable steady state or asymptotically stable manifolds of steady states. In metabolic networks with general stoichiometry the steady states are not always stable and we provide conditions for their stability. In order to demonstrate the biological relevance we illustrate the results on the examples of the TCA cycle, the mevalonate pathway and the Calvin cycle.

Clb3-centered regulations are recurrent across distinct parameter regions in minimal autonomous cell cycle oscillator designs.

Some biological networks exhibit oscillations in their components to convert stimuli to time-dependent responses. The eukaryotic cell cycle is such a case, being governed by waves of cyclin-dependent kinase (cyclin/Cdk) activities that rise and fall with specific timing and guarantee its timely occurrence. Disruption of cyclin/Cdk oscillations could result in dysfunction through reduced cell division. Therefore, it is of interest to capture properties of network designs that exhibit robust oscillations. Here we show that a minimal yeast cell cycle network is able to oscillate autonomously, and that cyclin/Cdk-mediated positive feedback loops (PFLs) and Clb3-centered regulations sustain cyclin/Cdk oscillations, in known and hypothetical network designs. We propose that Clb3-mediated coordination of cyclin/Cdk waves reconciles checkpoint and oscillatory cell cycle models. Considering the evolutionary conservation of the cyclin/Cdk network across eukaryotes, we hypothesize that functional ("healthy") phenotypes require the capacity to oscillate autonomously whereas dysfunctional (potentially "diseased") phenotypes may lack this capacity.

Youth smoking and anti-smoking policies in North Dakota: a system dynamics simulation study.

BACKGROUND: The current study utilizes system dynamics to model the determinants of youth smoking and simulate effects of anti-smoking policies in the context of North Dakota, a state with one of the lowest cigarette tax rates in the USA. METHODS: An explanatory model was built to replicate historical trends in the youth smoking rate. Three different policies were simulated: 1) an increase in cigarette excise taxes; 2) increased funding for CDC-recommended comprehensive tobacco control programs; and 3) enforcement of increased retailer compliance with age restrictions on cigarette sales. RESULTS: The explanatory model successfully replicated historical trends in adolescent smoking behavior in North Dakota from 1992 to 2014. The policy model showed that increasing taxes to $2.20 per pack starting in 2015 was the most effective of the three policies, producing a 32.6% reduction in youth smoking rate by 2032. Other policies reduced smoking by a much lesser degree (7.0 and 3.2% for comprehensive tobacco control program funding and retailer compliance, respectively). The effects of each policy were additive. CONCLUSIONS: System dynamics modeling suggests that increasing cigarette excise taxes are particularly effective at reducing adolescent smoking rates. More generally, system dynamics offers an important complement to conventional analysis of observational data.