Feature Selection Approaches In Antibody Display

Molecular diagnostics tools provide specific data that have high dimensionality due to many factors analyzed in one experiment and few records due to high costs of the experiments. This study addresses the problem of dimensionality in melanoma patient antibody display data by applying data mining feature selection techniques. The article describes feature selection ranking and subset selection approaches and analyzes the performance of various methods evaluating selected feature subsets using classification algorithms C4.5, Random Forest, SVM and Naïve Bayes, which have to differentiate between cancer patient data and healthy donor data. The feature selection methods include correlation-based, consistency based and wrapper subset selection algorithms as well as statistical, information evaluation, prediction potential of rules and SVM feature selection evaluation of single features for ranking purposes

ONTOLOGY-BASED SYSTEM DEVELOPMENT FOR MEDICAL DATABASE ACCESS

Medical research is a complex multi-disciplinary task involving specialists from different fields and professions, not only medical professionals. Medical databases are structured by information technology experts, but the contents must be tailored to the medical field. When the medical staff defines the information they use, terminology from their particular field of expertise is employed. This leads to misunderstandings between the maintainers and developers of information technology solutions, and the users of those solutions. When the time comes that a user, who is a medical professional, requires very specific data from the database, the chance of obtaining the data incorrectly is very high. By defining specific concepts and relationships between the data, in an explicit shared specification, some of the above problems can be avoided. The developed ontology-based data access system, described in this paper, provides a tool to store, manage and use definitions of common terminology and their mappings to the database. It is also capable of reasoning about the relationships between terms and indicates inconsistencies of term definitions, if any are present. By defining these interconnected terms in the ontology and by working through the system, all experts and software tools, who use the data, are able to use and reuse these terms to obtain data in a reliable and predefined way. This paper discusses the development and implementation of the ontology-based data access system, the ontology describing the medical data and the data mapping system, linking data from the database to concepts and virtual ontology individuals

The Riga East University Hospital Stroke Registry-An Analysis of 4915 Consecutive Patients with Acute Stroke

Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Background and Objectives: A hospital-based stroke registry is a useful tool for systematic analyses of the epidemiology, clinical characteristics, and natural course of stroke. Analyses of stroke registry data can provide information that can be used by health services to improve the quality of care for patients with this disease. Materials and Methods: Data were collected from the Riga East University Hospital (REUH) Stroke Registry in order to evaluate the etiology, risk factors, clinical manifestations, treatment, functional outcomes, and other relevant data for acute stroke during the period 2016-2020. Results: During a five-year period, 4915 patients (3039 females and 1876 males) with acute stroke were registered in the REUH Stroke Registry. The causative factors of stroke were cardioembolism (45.7%), atherosclerosis (29.9%), lacunar stroke (5.3%), stroke of undetermined etiology (1.2%), and stroke of other determined causes (1.2%). The most frequent localizations of intracerebral hemorrhage were subcortical (40.0%), lobar (18.9%), and brainstem (9.3%). The most prevalent risk factors for stroke were hypertension (88.8%), congestive heart failure (71.2%), dyslipidemia (46.7%), and atrial fibrillation (44.2%). In addition, 1018 (20.7%) patients were receiving antiplatelet drugs, 574 (11.7%) were taking statins, and 382 (7.7%) were taking anticoagulants. At discharge, 35.5% of the patients were completely independent (mRS (modified Rankin Scale) score: 0-2), while 49.5% required some form of assistance (mRS score: 3-5). The intrahospital mortality rate was 13.7%, although it was higher in the hemorrhage group (30.9%). Conclusions: Our stroke registry data are comparable to those of other major registries. Analysis of stroke registry data is important for improving stroke care and obtaining additional information for stroke studies.publishersversionPeer reviewe

The Role of an Artificial Intelligence Method of Improving the Diagnosis of Neoplasms by Colonoscopy

Funding Information: The project is funded by the European Regional Development Fund (ERDF) 1.1.1.1. project “Practical Studies”, 4th phase, project ID Nr. 1.1.1.1/20/A/035. Publisher Copyright: © 2023 by the authors.BACKGROUND: Colorectal cancer (CRC) is the third most common cancer worldwide. Colonoscopy is the gold standard examination that reduces the morbidity and mortality of CRC. Artificial intelligence (AI) could be useful in reducing the errors of the specialist and in drawing attention to the suspicious area. METHODS: A prospective single-center randomized controlled study was conducted in an outpatient endoscopy unit with the aim of evaluating the usefulness of AI-assisted colonoscopy in PDR and ADR during the day time. It is important to understand how already available CADe systems improve the detection of polyps and adenomas in order to make a decision about their routine use in practice. In the period from October 2021 to February 2022, 400 examinations (patients) were included in the study. One hundred and ninety-four patients were examined using the ENDO-AID CADe artificial intelligence device (study group), and 206 patients were examined without the artificial intelligence (control group). RESULTS: None of the analyzed indicators (PDR and ADR during morning and afternoon colonoscopies) showed differences between the study and control groups. There was an increase in PDR during afternoon colonoscopies, as well as ADR during morning and afternoon colonoscopies. CONCLUSIONS: Based on our results, the use of AI systems in colonoscopies is recommended, especially in circumstances of an increase of examinations. Additional studies with larger groups of patients at night are needed to confirm the already available data.publishersversionPeer reviewe

Sociodemographic, lifestyle and medical factors associated with Helicobacter Pylori infection

Q4Q2Paciente adultoBackground & Aims: The prevalence of Helicobacter pylori (H. pylori) infection is higher in developing countries and is often linked to lower socioeconomic status. Few studies have investigated the association between H. pylori and individual level characteristics in Europe, where several countries have a high prevalence of H. pylori infection. The study aimed to identify risk factors for H. pylori infection among adults in a large clinical trial in Latvia. Methods: 1,855 participants (40-64 years) of the “Multicenter randomized study of H. pylori eradication and pepsinogen testing for prevention of gastric cancer mortality” (GISTAR study) in Latvia tested for H. pylori IgG antibodies were included in a cross-sectional analysis. Sociodemographic, lifestyle and medical factors were compared for participants seropositive (H. pylori+) and seronegative. Mutually adjusted odds ratios (OR) were calculated for H. pylori+ and factors significant in univariate analysis (education, smoking, binge drinking, several dietary habits, history of H. pylori eradication and disease), adjusting for age, gender and income. Results: Of the participants 1,044 (55.4%) were H. pylori seropositive. The infection was associated with current (OR: 1.34, 95%CI: 1.01-1.78) and former (OR: 1.38; 95%CI: 1.03-1.85) smoking, binge drinking (OR: 1.35; 95%CI: 1.03-1.78), having ≥200g dairy daily (OR: 1.37; 95%CI: 1.11-1.69), and very hot food/drinks (OR: 1.32; 95%CI: 1.03-1.69) and inversely with ≥400g vegetables/fruit daily (OR: 0.76; 95%CI: 0.60-0.96), history of H. pylori eradication (OR: 0.57; 95%CI: 0.39-0.84), peptic ulcer (OR: 0.55; 95%CI: 0.38-0.80) and cardiovascular disease (OR: 0.78; 95%CI: 0.61-0.99). Conclusions: After mutual adjustment, H. pylori seropositivity was associated with lifestyle and in particular dietary factors rather than socioeconomic indicators in contrast to the majority of other studies.https://scholar.google.com/citations?user=xFiKCkMAAAAJ&hl=eshttp://scienti.colciencias.gov.co:8081/cvlac/visualizador/generarCurriculoCv.do?cod_rh=0000264474Revista Nacional - Indexad

Does family history of cancer influence undergoing screening and gastrointestinal investigations?

Q2Background and Aims: Although a family history of cancer (FHC) can modify the lifestyle and attitudes towards participation in cancer screening programs, studies on this relationship show mixed results and vary across populations. The objectives of the study were to compare sociodemographic characteristics, history of gastrointestinal (GI) investigations and Helicobacter pylori eradication, and modifiable cancer risk factors between those with FHC and those with no FHC (NFHC), and to investigate the association between FHC and a history of GI investigations. Methods: A total of 3,455 questionnaires from the pilot study of the “Helicobacter pylori eradication and pepsinogen testing for prevention of gastric cancer mortality (GISTAR study)” in Latvia were analysed. We compared sociodemographic characteristics and history of GI investigations between participants with self- reported FHC and NFHC. Binary logistic regression models adjusted for socio-demographic characteristics and modifiable cancer risk factors were built for a FHC and each GI investigation. Results: Participants with a FHC were more likely to be women, have a higher education and less likely to have harmful habits (smoking, alcohol consumption) than those with NFHC. Participants with a FHC were approximately twice as likely to report recent colorectal investigations specifically for screening, than those with NFHC. In fully adjusted logistic regression models, FHC was significantly associated with a recent history of faecal occult blood tests (FOBTs), colonoscopies, and colorectal investigations (FOBT or colonoscopy) specifically for screening as part of the national organized screening programme. Conclusion. Our results indicate that those with a FHC have different patterns of health-related behaviour than those with NFHC.https://orcid.org/0000-0001-7187-9946Revista Internacional - Indexad

Modular Point-of-Care Breath Analyzer and Shape Taxonomy-Based Machine Learning for Gastric Cancer Detection

Funding Information: The development of the analysis approach and its evaluation and analysis were supported by a postdoctoral grant within the Activity 1.1.1.2 “Post-doctoral Research Aid” co-funded by the European Regional Development Fund (postdoctoral project numbers: 1.1.1.2/VIAA/2/18/270 and 1.1.1.2/VIAA/3/19/495). Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Background: Gastric cancer is one of the deadliest malignant diseases, and the non-invasive screening and diagnostics options for it are limited. In this article, we present a multi-modular device for breath analysis coupled with a machine learning approach for the detection of cancer-specific breath from the shapes of sensor response curves (taxonomies of clusters). Methods: We analyzed the breaths of 54 gastric cancer patients and 85 control group participants. The analysis was carried out using a breath analyzer with gold nanoparticle and metal oxide sensors. The response of the sensors was analyzed on the basis of the curve shapes and other features commonly used for comparison. These features were then used to train machine learning models using Naïve Bayes classifiers, Support Vector Machines and Random Forests. Results: The accuracy of the trained models reached 77.8% (sensitivity: up to 66.54%; specificity: up to 92.39%). The use of the proposed shape-based features improved the accuracy in most cases, especially the overall accuracy and sensitivity. Conclusions: The results show that this point-of-care breath analyzer and data analysis approach constitute a promising combination for the detection of gastric cancer-specific breath. The cluster taxonomy-based sensor reaction curve representation improved the results, and could be used in other similar applications.publishersversionPeer reviewe

The diagnostic value of anti-parietal cell and intrinsic factor antibodies, pepsinogens, and gastrin-17 in corpus-restricted atrophic gastritis

Raksta tekstā kļuda: afilācijai "Digestive Diseases Centre GASTRO Ltd", norādīta atrašanas vieta: Hong Kong, ChinapublishersversionPeer reviewe

Assessment of Serum Pepsinogens with and without Co-Testing with Gastrin-17 in Gastric Cancer Risk Assessment—Results from the GISTAR Pilot Study

Introduction-Serum pepsinogen tests for gastric cancer screening have been debated for decades. We assessed the performance of two pepsinogen assays with or without gastrin-17 for the detection of different precancerous lesions alone or as a composite endpoint in a Latvian cohort. Methods-Within the intervention arm of the GISTAR population-based study, participants with abnormal pepsinogen values by ELISA or latex-agglutination tests, or abnormal gastrin-17 by ELISA and a subset of subjects with all normal biomarker values were referred for upper endoscopy with biopsies. Performance of biomarkers, corrected by verification bias, to detect five composite outcomes based on atrophy, intestinal metaplasia, dysplasia or cancer was explored. Results-Data from 1045 subjects were analysed, of those 273 with normal biomarker results. Both pepsinogen assays showed high specificity (>93%) but poor sensitivity (range: 18.4-31.1%) that slightly improved when lesions were restricted to corpus location (40.5%) but decreased when dysplasia and prevalent cancer cases were included (23.8%). Adding gastrin-17 detection, sensitivity reached 33-45% while specificity decreased (range: 61.1-62%) and referral rate for upper endoscopy increased to 38.6%. Conclusions-Low sensitivity of pepsinogen assays is a limiting factor for their use in population-based primary gastric cancer screening, however their high specificity could be useful for triage