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Modern Techniques in Data Analysis, with Application to the Water Pollution

Abstract

This paper presents a comparison of most capable families of distributions for modelling asymmetry. Kum-normal, stable-symmetric normal family and two of the full families were chosen, where the quality of the fit, the flexibility and the amount of asymmetry parameters were factors used for comparison. The objective of this study was to generate data with increasing levels of asymmetry and to choose the best fit. The distributions were also compared in modelling two data sets of pollution of the drinking water in the El-Sharkia governorate in Egypt. Much of this paper is concerned with the distribution theory, exploring the properties of some new recent families of distributions and, where appropriate, extolling their virtues. Relatively, much of this paper is devoted to practical application.

Open access
Non-Invasive Diagnosis of Gastroesophageal Reflux Disease Using Gastrin- and Pepsinogen-Based Tests

Abstract

Gastrin-17 (G-17), pepsinogen-1 (Pg1) and pepsinogen-2 (Pg2) reflect the functional state of gastric mucosa and are used for non-invasive diagnosis and screening of atrophic gastritis. The aim of the study was to clarify if erosive reflux disease (ERD) or non-ERD (NERD) can be distinguished from other dyspeptic conditions in patients, in a non-invasive manner using specific biomarkers. Levels of G-17, Pg1, and Pg2 were measured in 141 ERD patients (median age 48 years, males — 68), 122 NERD patients (median age 45 years, males — 32) and 410 control patients (median age 50 years, males — 97). Levels of biomarkers in ERD and NERD groups were compared to controls. Median levels of G-17 (1.94 vs 2.92 pmol/L, p = 0.036) and Pg2 (6.70 vs 7.79 µg/l, p = 0.046) were lower in the ERD group compared to control patients; no difference with respect to the control was found for the NERD group. After exclusion of the patients having at least one potential condition that might modify the levels of the biomarkers (gastric mucosa atrophy, Helicobacter pylori colonisation), no difference in levels of biomarkers was observed with respect to the control for both the ERD and NERD groups. G-17, Pg1, and Pg2 based tests cannot be used to distinguish ERD or NERD from other dyspeptic conditions in patients.

Open access
Overlaps in the Pathogenesis of Rosacea and Atherosclerosis

Abstract

Rosacea is a chronic inflammatory skin disease characterised by transient or persistent erythema, telangiectasia, papules, and pustules that predominantly involve central regions of the face. Recent studies have shown a possible clinical association between rosacea and cardiovascular diseases (CVDs). Rosacea and atherosclerosis are both known to have alterations in the innate immune system, enhanced oxidative and endoplasmic reticulum stress. The aim of this review is to delve deep into the pathogenesis of rosacea and atherosclerosis to uncover possible pathogenic overlaps between these chronic inflammatory diseases.

Open access
Phenolics Content in Buckwheat Flour

Abstract

The objective of the current study was to analyse the total phenolic concentration (TPC), total flavonoid concentration (TFC), individual phenolic compound concentration and DPPH′ radical scavenging activity of four buckwheat (raw, roasted, white and dark) flour samples obtained from the Latvian market, in comparison to those of wheat flour, which is the most common ingredient in production of cereal products. TPC, TFC, and DPPH′ radical scavenging activity values were determined using spectrophotometric methods. Phenolic compounds were determined based on the high performance liquid chromatographic method (HPLC). All buckwheat flour samples had significantly higher TPC and TFC than wheat flour. The highest TPC (974.74 mg GAE·100 g−1 DW) and TFC (495.31 mg CE·100 g−1 DW) was found in raw buckwheat flour (p < 0.05). Buckwheat flour samples demonstrated similar DPPH′ radical scavenging activity, which ranged from 21.067 to 22.644 mM TE·100 g−1 dry matter, and was significantly higher (p < 0.05) than in wheat flour (0.731 mM TE·100 g−1 of dry matter). Dark buckwheat flour contained the highest level of rutin (4.613 mg·100 g−1), whereas raw buckwheat flour displayed the highest level of 3.5-dihydroxybenzoic acid (6.356 mg·100 g−1), sinapic acid (0.947 mg·100 g−1) and epicatechin (2.608 mg·100 g−1).

Open access
Population Genetics of Latvians in the Context of Admixture between North-Eastern European Ethnic Groups

Abstract

This article presents a review on population genetics of Latvians, which alongside Lithuanians are the two extant Baltic speaking populations. The article provides a description of genome-wide single nucleotide polymorphism (SNP) data and contains a comparative analysis of the results of studies performed on classical autosomal genetic markers, mitochondrial DNA (mtDNA) and the non-recombining part of the Y chromosome (NRY), with data on neighbouring populations. The study also covers data of recently performed ancient DNA (aDNA) studies carried out on samples from the territory of today’s Latvia. The results of population genetic studies have shown a mixture of eastern and western genetic traits in present-day Latvians with only small differences between Latvian subpopulations. Studies of the Baltic “tribal gene” LWb, as well as the gene’s SERPINA1 allele PIZ have indicated the presence of a considerable Baltic admixture in the neighbouring Finno-Ugric and Slavic populations. Although mtDNA analyses have shown that Latvians genetically in general belong to the same common gene pool as most of the Europeans, the Y-chromosomal lineage composition suggests that they are most similar to Northern and Eastern European populations of Lithuanians, Estonians, and Eastern-Slavic populations, which are ethnogenetically closest to them. The analysis of aDNA from the Early and Middle Neolithic did not present any genomic evidence of gene-flow from Central European farmers or any mitochondrial or Y-chromosomal haplogroups that are typical for them in the hunter-gatherers from the territory of today’s Latvia and Lithuania.

Open access
Variation in β-Glucan, Protein and Fat Concentration of Oats Created in Latvia

Abstract

Consumption of dietary fibre has potential in improving nutrition and health. For further breeding of oats, it is necessary to increase knowledge on variation in the content of fibre and bioactive components in oats. Therefore, the aim of the present investigation was to study the extent of variation in β-glucan concentration of oats grown in Latvia and to evaluate association of β-glucan concentration with protein and fat concentration in newly created oat breeding lines. In 2015 and 2016, concentration of protein, fat, and β-glucan in grain of hulled oat varieties ‘Laima’, ‘Peppi’, and ten breeding lines was determined. The obtained results showed a wide range of fat concentration among varieties, with a range from 5.9 to 8.3%. The concentration of β-glucan ranged from 1.8 to 3.6% depending on the year. The β-glucan concentration had medium close positive correlation with lipid and weak significant positive correlation with protein concentration, which significantly differed among genotypes.

Open access
Chronic Total Coronary Artery Occlusion Recanalisation with Percutaneous Coronary Intervention — Single Centre 10-Year Experience

Abstract

Coronary artery chronic total occlusions (CTO) are common — approximately one-third of patients with significant coronary artery disease on angiography have at least 1 CTO. Invasive treatment of these lesions still remain a major challenge for interventional cardiology due to their complexity. Historically, success rates have improved to about 60–70% by using only the traditional antegrade approach. The results have dramatically improved during the last decade after more widespread application of new retrograde techniques. The aim of our study was to review and analyse single hospital experience in CTO invasive treatment and to evaluate the long-term results. A total of 519 patients undergoing percutaneous coronary interventions (PCI) for CTO at a single tertiary PCI centre (Rīga East University Hospital), were included in the study. The median age was 64 years (38–88), and 80% were male. The retrograde approach (RA) was used for 167 (32.2%) of the CTO PCI patients. The overall patient success rate was 81.3% and it increased from 73.9% in 2007 to 95.2% in 2015 (p < 0.001). Mean patient observation time was five years. Overall survival was found significantly better in patients group after successful CTO PCI procedures (Long-rank test, p = 0.013).

Open access
The Impact of Body Mass Index on Disease Progression in Ankylosing Spondylitis

Abstract

Obesity can be a factor that affects the course of chronic systemic inflammatory arthritis. The objective of this study was to characterise patients with ankylosing spondylitis (AS) according to an evaluation of their body mass index (BMI) and by exploring the link between the overweightness and obesity with routinely measured disease-specific variables, including disease activity (Bath Ankylosing Spondylitis Disease Activity Index BASDAI; Ankylosing Spondylitis Disease Activity Score, using CRP, ASDAScrp), spinal mobility (Bath Ankylosing Spondylitis Metrology Index, BASMI), functional capacity (BASFI), extraspinal manifestations like fatigue, uveitis, and peripheral arthritis present during the course of the disease. A total of 107 patients were included in the cross-sectional study fulfilling the modified New York criteria for AS. Patients were divided into three groups: with the evaluation of BMI ≤ 24.9, 25.0–29.9 (overweight) and ≥ 30.0 (obesity). The mean BMI was 25.13 (SD 4.07). 33% of patients were overweight and 15% were obese. The mean values of age, duration of AS, ASDAScrp, BASDAI, Bath Ankylosing Spondylitis Functional Index (BASFI), BASMI, pain in spine, and fatigue in the group with BMI ≤ 24.9 were lower than in the other groups (p < 0.05). There was no difference between groups in age of AS onset, uveitis and peripheral arthritis. AS patients who were overweight or obese had a higher level of the disease activity, pain, fatigue, functional disability and spinal mobility impairment with worse values in the case of obesity.

Open access
Impact of Intense Pulsed Light Therapy on the Quality of Life of Rosacea Patients

Abstract

Rosacea is a chronic inflammatory skin disorder affecting predominantly adult patients. The aim of the current investigation was to evaluate clinical response by using quality of life assessment before and after an IPL (intensive pulsed light) therapy course for patients sufferring from rosacea treated in the outpatient clinic “Health and Aesthetics” in Rīga during a one-year period (in 2016). All patients presented with typical clinical symptoms of rosacea on the face — acneiform papules, pustules, telangiectasia, centrofacial erythema, and complaints about flushing and burning. In the current study, 100 rosacea patients treated with IPL therapy were selected. Each patient filled in the quality of life questionnaire before and after two courses of IPL therapy. The interval between IPL therapy sessions was one month. The results reflected comprehensive benefit from IPL therapy for all rosacea patients. No serious side effects from IPL therapy were detected. Side effects like mild eythema after procedure (75%), mild oedema (10%), vesiculation (3%), and hyperpigmentation (8%) were completely resolved within four weeks after completion of treatment. In all patients, quality of life assessment showed a statistically significant increase after two courses of IPL therapy.

Open access
Influence of a Modified Plant Extract on Activity of Antioxidant Enzymes and Concentration of Pigments in Gamma-Irradiated Plants of Maize and Wheat

Abstract

The influence of a medicinal plant extract, immobilised by ligands, on the activity of antioxidant enzymes and photosynthetic pigment concentration of wheat and maize was studied. The object of study was seed of drought-resistant firm durum wheat (Triticum durum Desf.) and maize (Zea mays L.). Seeds were subjected to general uniform γ-radiation from a 60Co source on a Rkhund installation at average dose power of MD = 0.306 Gy/sec. Before radiation seeds were treated in modified extract from medicinal plants. The treatment of seeds with 0.1 and 0.01% solution of modified extract from Hypericum, Dandelion, and Calendula caused significant reduction in processes initiated by radiation and in formation of free radicals. On the basis of the obtained results it was concluded that the used modified plant extract collection had a protective effect, reducing the amount of free radicals produced by γ-irradiation.

Open access