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Association Between 4q25 Variants, Risk of Atrial Fibrillation and Echocardiographic Parameters

Abstract

Atrial fibrillation (AF), the most common type of arrhythmia, has a heritable component. Variants at locus 4q25 are best associated with the risk of AF development in genome-wide association studies. Left atrial volume is an independent predictor of recurrence of AF after successful sinus rhythm restoration. The aim of our study was to investigate potential association between genetic variants at 4q25 locus and the risk of AF and echocardiographic parameters. We included 241 AF patients and 119 control individuals into the study. Left ventricle ejection fraction (LVEF, %) and left atrial volume index (LAVI, ml/m2) were assessed by transthoracic echocardiography during outpatient visits. We selected five 4q25 genetic variants (rs6825911, rs1126483, rs10004516, rs6838973, rs2200733) for the analysis. Variant rs6838973 was found to be associated with reduced risk of AF in additive (CCTT) and dominant (CC vs. CT+TT) models of inheritance. On the other hand, additive (CC<CT<TT) and dominant (CC vs. CT+TT) models of rs2200733 were associated with greater risk of AF. The same variations were found to be associated with age of AF onset. Median LAVI was 39.0 ml/m2 (IQR = 10.0) and median LVEF was 56.0% (IQR = 13.0). Statistically significant association was observed only between LAVI and variant rs1126483 in the dominant model of inheritance (median LAVI in CC vs. CT+TT – 38 ml/m2 vs. 40 ml/m2, U = 1602.5, p = 0.032). No significant association was found for LVEF and the analysed genotypes.

Open access
Cultivation of 3D Dermal Tissue by Application of Autologous Matrix

Abstract

The most common reasons for major skin loss are thermal trauma — burns and scalds that can result in rapid, extensive, deep wounds as well as chronic non-healing wounds. Treatment using common techniques is poor and depending on the trauma level can result in death. There is a substantial need for skin integrity restoration. The main goal of this study was to develop an autologous 3D skin model that could eventually be translated into clinical applications. The study examined a variety of factors — extracellular matrix components, cell count, culture medium modification and role of structurally and functionally high-quality 3D skin dermis layer tissue culture production. The results of this study are an essential prerequisite to standardise the use of both clinical, as well as in vitro test systems. Dermal cell lines applied in the study were isolated form patient biopsies obtained at Pauls Stradiņš Clinical University Hospital. Blood plasma type AB was used for fibrin matrix formation. As catalysts, CaCl2 or calcium gluconate, and tranexamic acid were applied. 3D tissue functionality was assessed by evaluation of gene expression and changes in growth factor secretion. Fibrin matrix formulations with 1% and 1.5% CaCl2 and 5 mg, 7 mg and 10 mg tranexamic acid concentration were tested. Better matrix properties were observed with higher concentration of CaCl2 and tranexamic acid. Differences in levels of collagen gene expression and growth factor secretion were observed. Changes in levels of fibroblast growth factor and gene expression were observed in fibrin matrix samples and the surface-cultivated cell culture monolayer, but structural protein synthesis was not detected.

Open access
Diagnostics and Treatment Strategies of Early (T1) Lower Lip Cancer

Abstract

Data from 35 patients were analysed to identify the main factors that may have predisposed the unfavourable clinical course in early diagnosed lower lip cancer. Of 35 patients who were sent to the Oncology Centre of Latvia, Rīga East University Hospital, with the diagnosis of early lower lip cancer, histologically diagnosis was confirmed for 22 patients. Sizes of the primary tumours were less than 2 cm (T1 size tumour). Vermilionectomy was carried out for 17 patients, wedge- or V-shaped resection was performed for 13 patients, and in five cases patients refused to receive surgical treatment and received radiation therapy instead. Review of the reports of the histological criteria for patients with aggressive course of the illness with relapses, regional metastases and also in cases of death, showed that vermilionectomy can be considered an effective diagnostic and therapeutic operation.

Open access
Exercise, Chronotropic and Inotropic Capacity in Athletes with Different Training Programmes

Abstract

Amateur sport has significant influence on peoples’ physical activity and affects the prevalence of non-communicable diseases. The population of competing amateur athletes has not been sufficiently studied, and there is a huge gap between functional results of untrained individuals and professional athletes. The aim of the study was to evaluate the exercise capacity and chrono-tropic, inotropic capacity in amateur athletes with different training programmes, as assessed by cardiopulmonary exercise testing. In a longitudinal prospective study, 600 amateur athletes who performed high dynamic load sports, according to the Mitchell Classification of Sports, were assessed. The individuals underwent standard maximum cardiopulmonary exercise testing on the ISO certified Master screen CPX system. The exercise capacity was dependent on the training programme organisation, regularity and duration, but it was not dependent on age. During maximum work-rate, the functional parameters of the cardiorespiratory system and inotropic capacity were significantly dependent on duration of the training programme. Chronotropic and inotropic capacity, as well as cardiorespiratory adaptation were significantly higher for competing amateur athletes of both genders than for untrained individuals. The study showed that amateur athletes with a training programme 300 minutes per week had higher exercise capacity, which was based on the individually suitable training programme, and higher aerobic and anaerobic capacity. Regular pre-competition medical assessment of amateur athletes can be used to objectively evaluate their health condition, adaptation, cardiac risk and make changes in the athletes’ training programme.

Open access
Phylogenetic Relationships Between Zokors Myospalax (Mammalia, Rodentia) Determined on the Basis of Morphometric and Molecular Analyses

Abstract

Phylogenetic relationships between zokors living in different territories of Russia: Altai zokors Myospalax myospalax from “Altai” (Altai Republic and Altaiskii Krai) and “Priobie” from the River Ob zone (Tomsk oblast and Novosibirsk oblast) and subspecies M. m. tarbagataicus from Kazakhstan (ridge Tarbagatai) and M. aspalax and M. psilurus from Zabaikalskii Krai were determined on the basis of craniometrical and molecular analysis of the mitochondrial 12S rRNA gene. The comparison of the craniometrical and molecular data revealed significant differences between the Altai zokors of the “Priobie” (the River Ob zone) and “Altai” populations. The importance of geographic isolation to the formation of morphometric and genetic differentiation of distinct geographic forms of the investigated zokors is shown. Specific ecological and morphological adaptations and distinct genetic features of two forms of zokors indicate the existence of separate subspecies of the species M. myospalax.

Open access
Physiological Responses of Wetland Species Rumex Hydrolapathum to Increased Concentration of Biogenous Heavy Metals Zn and Mn in Substrate

Abstract

The aim of the present study was to determine if individuals of Rumex hydrolapathum Huds native to saline wetlands are able to tolerate high concentration of biogenous heavy metals Zn and Mn in substrate and to accumulate high concentration of these metals in aboveground parts. Plant physiological status was monitored by using non-destructive analysis of chlorophyll and chlorophyll a fluorescence. R. hydrolapathum plants accumulated up to 1840 mg·kg−1 Zn and 6400 mg·kg−1 Mn in older leaves. The usefulness of monitoring changes in chlorophyll concentration and chlorophyll a fluorescence parameters to predict physiological response of R. hydrolapathum plants to excess Zn and Mn was not supported, as the lack of significant changes indicated that the model species showed adaptation to increased amount of metals in actively photosynthesizing tissues. It appears that Zn and Mn tolerance of R. hydrolapathum is based primarily at the physiological level where metal accumulation in younger leaves and roots is restricted, and development of new leaves is promoted together with induction of senescence in older leaves that have accumulated the majority of Zn and Mn. R. hydrolapathum can be characterised as a very promising model species for further studies for practical phytoremediation needs.

Open access
Risk Factor Analysis for Gout in the Latvian Population

Abstract

Gout (Gr. podagra) is a multifactorial pathology, which means that both genetic and environmental factors play a role in the aetiology of the disease. For these reasons, revealing risk factors could be of very high importance in prevention and treatment of gout. In the present study, we found that a major role in gout predisposition is played by specific alleles in the ABCG2 gene. The study used survey data for 43 gout patients and 99 healthy control individuals who were geno-typed for rs2231142. It was found that allelic variant rs2231142 in the ABCG2 gene had the strongest association with gout. Among other co-factors studied, sex, and increased body mass index were associated with gout.

Open access
Application of Metabolomic Analysis in Exploration of Plant Genetic Resources

Abstract

The article addresses the issues of using metabolomic analysis to study genetic resources of cereal crops in order to (1) determine phylogenetic linkages between species (the degree of domestication); (2) within species to describe genetic diversity according to its responses to biotic and abiotic stressors and biochemical characteristics (chemical compounds) determining food, feed and technological quality indicators; and (3) select the most resistant and highest-quality geno-types for complex breeding use.

Open access
Content of Phenolic Compounds and Antioxidant Activity in Fresh Apple, Pomace and Pomace Water Extract — Effect of Cultivar

Abstract

The study aimed to evaluate the chemical composition (total phenol, flavonoid, and tannin content and the antioxidant activity) of 11 apple (Malus domestica) cultivars in fresh apples and their processing by-products — apple pomace and its water extract. In addition, the proportion of chemical compounds and antioxidant activity in fresh apples and pomace transferred to the resulting water extract was calculated. Three different season’s cultivars (autumn–winter, winter and late winter) were selected in the research, and significant differences between chemical parameters within groups were found. Cultivars ‘Zarja Alatau’, ‘Belorusskoje Malinovoje’, ‘Sinap Orlovskij’ and ‘Antej’ are characterised by a higher content of determined compounds in fresh apples, pomace and po-mace water extract. The results showed that the water extract in relation to fresh apples and apple pomace still contains an appropriate amount of total phenols, flavonoids and tannins in the range 2.5–9.6%. These results indicated that apple pomace water extracts could be recommended for use in food as well as in the pharmaceutical industry.

Open access
Effect of Soil Properties on the Spread of Heterobasidion Root Rot

Abstract

The literature review focuses on the effect of forest soil properties on infection of coniferous trees and stumps by Heterobasidion spores and further growth of mycelium from tree to tree. Spread of the fungus is greater in alkaline soil. Forest plantations on former agricultural lands have an increased risk of infection, due to lack of antagonistic soil microorganisms. In Latvia, severe infection of spruce stands by Heterobasidion root rot has been observed on peat soils.

Open access