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Open access

Ekaterina N. Baranova, Inna A. Chaban, Neonila V. Kononenko, Alexander A. Gulevich, Ludmila V. Kurenina and Elena A. Smirnova

Abstract

We investigated how an abiotic factor, i.e. salinity, affects specific intracellular organelles of cells of the root cap. We focused on: 1) amyloplasts, which are specific plastids of the cap that perform important metabolic and sensory functions; and 2) mitochondria, which protect cells from ROS damage by changing their ultrastructure. In our work we studied the ultrastructural changes of these organelles in different areas of the root cap under NaCl and Na2SO4 impact. We showed that the amyloplasts (statoliths) and mitochondria of the columella and the peripheral zone of the cap change their structural organisation in the presence of NaCl. Under action of Na2SO4, in plastids of columella the number of starch grains decreases dramatically, the cells of the peripheral part of the cap do not contain the amyloplasts, and the proplastids that do not store or store a little starch grains, which is attributed to leucoplasts with typical lamellae characteristic for root cortex cells. Thus, Na2SO4 influence has the most significant effect on the plastids of the root cap, and plastids of the cells of the peripheral zone of the cap are subjected to the most significant changes under salinity stress.

Open access

Baiba Zandersone, Elita Medvedja, Arnolds Jezupovs, Iveta Līduma, Solvita Selderiņa, Sandra Leja, Sintija Sausa and Tatjana Tračevska

Abstract

Colonisation of gastrointestinal tract by extended spectrum beta lactamase (ESBL)-producing Gram-negative bacteria is a source for infections. The present work is a prospective study in Latvia aimed to determine the role of two surgical profile wards in transmission of ESBL-producing bacteria. Differences between hospital wards were not analysed due to low number of patients. We have also determined a correlation between the duration of hospitalisation and risk of ESBL colonisation. Tests for ESBL-producing bacteria were made twice for 136 patients — upon admission and upon discharge from the hospital. Of them, 21 (15.4%) patients already were ESBL-positive at the time of admission and 115 (84.6%) patients were ESBL-negative. Upon discharge from hospital, 45 (33.1%) patients were ESBL-positive, one patient was ESBL-negative, and 25 (18.4%) of ESBL-positive cases had emerged during hospitalisation. In total, 46 (33.8%) from 136 patients were ESBL-positive and ESBL was positive in 51 bacterial isolates. On discharge from hospital, the newly acquired ESBL-positive bacterial isolates were K. pneumoniae (n = 18), E. coli (n = 7) and P. mirabilis (n = 3). The prevalence of ESBL-positive E. coli from all detected E. coli was 7.0% and from all Klebsiella spp. — 88.9% in gut flora. Analysis of patientassociated wound infections did not show correlation between the ESBL-producing gut microbiota and the bacterial species involved in wound infection.

Open access

Nataliya I. Nenko, Irina A. Ilyina, Galina K. Kiseleva and Elena K. Yablonskaya

Abstract

The cold-tolerance of ‘Kristall’ (Euro-Amur-American origin), ‘Dostoyniy’ and ‘Krasnostop AZOS’ (interspecific hybrids of Euro-American origin) grapevine varieties in the winter conditions of South Russia is characterised by the second (true dormancy) and third (induced dormancy) winter-resistance components. Here we used a complex approach to estimate plant adaptation to abiotic stress factors. We used the gravimetric method for humidity assessment and water content, spectral analysis for detection of the protein level and pigments and capillary electrophoresis to determine the level of carbohydrates, Krebs cycle organic acids, phenolcarbonic, ascorbic acids, and amino acids. The obtained results allow to suggest various mechanisms of adaptation of the studied varieties to the winter period stressors. The water content of shoots, levels of protein, amino acids, proline, sugars and the sum of phenolcarbonic acid and ascorbic acid are the most informative indicators of grape plants frost-resistance in the climate conditions of the Anapa–Taman region.

Open access

Margit Olle and Ina Alsiņa

Abstract

All previous reviews of research on light-emitting diodes (LEDs) have been focused on how different light spectra generally influence plant yield and quality. There are no or almost no reviews on the effect of spectra on sugars or pigment concentration, or yield and growth etc. The role of visible light in food production, as in agriculture and horticulture, is obvious, as light drives photosynthesis, which is crucial for plant growth and development. Solid state lighting using LEDs represents a fundamentally different technology from gaseous discharge-type lamps currently in use. LEDs are important lamp types because the concentration of the light spectrum they emit can be changed to provide plants at various developmental stages with the light spectrum needed. A great deal of studies have been done on the effect of wavelengths of light on growth, yield and nutritional quality of greenhouse vegetables. However, little is known about the mechanisms by which the spectra affect sugar and pigment concentration, and yield, and growth. This article provides a list of how spectra influence the yield, growth, and nutritional quality of greenhouse-grown vegetables. Based on the given information we can conclude that blue, green, and red light are the main light colours that influence positively plant yield, growth and nutrient quality. Sometimes in specific situations, some other light colours are also beneficial, like far red light, orange light and UVA light. Future work on light colour manipulation has potential for producing lamps and greenhouse covers that better support plant yield, growth, and nutrition.

Open access

Linda Bāra, Jeļena Eglīte, Pēteris Ošs, Vinita Cauce, Vilnis Lietuvietis, Ludmila Vīksna, Elvīra Hagina and Angelika Krūmiņa

Abstract

Undeniably, sepsis is still a profoundly damaging and life-threatening condition for many individuals. With multiple changes in sepsis patients it is difficult to precisely classify an individual’s response in sepsis as proinflammatory or immunosuppressed. The aim of this study was to investigate genetically determined predisposition to developed sepsis by analysis of distribution of human leukocyte antigen (HLA) class II genes. Samples from patients with sepsis were collected at Pauls Stradiņš Clinical University Hospital, Latvia, in an intensive care unit between October 2016 and May 2017. The study group included 62 patients with sepsis, who were genotyped for HLA-DR; DQ using real time polymerase chain reaction – sequence specific primer (RT PCR-SSP). As a control group, data of 100 individuals were taken from the genetic bank of RSU Joint Laboratory of Clinical Immunology and Immunogenetics. The summarised results showed that the frequency of alleles DRB1*04:01 (OR = 5.54; 95% CI = 1.88–16.29); DRB1*07:01 (OR = 19.03; 95% CI = 2/37–152.82); DQA1*05:01 (OR = 14.17; 95% CI = 5.67–35.4); and DQB1*02:01 (OR = 50.00; 95% CI = 2.90–861.81) were significantly increased in patients with sepsis compared to the control group patients. The frequency of DRB1*16:01 (OR = 0.17, 95% CI = 0.04–0.59); DRB1*17:01 (OR = 0.04; 95% CI = 0.00–0.69); DQA1*01:01 (OR = 0.04; 95% CI = 0.00–0.31); DQA1*01:02 (OR = 0.03; 95% CI = 0.00–0.23); DQB1*02:02 (OR = 0.12; 95% CI = 0.03–0.42) alleles was lower in sepsis patients than in control subjects. The most frequent HLA-DRB1/DQA1/DQB1 haplotypes that was significantly increased in patients with sepsis were: DRB1*01:01/DQA1*05:01/DQB1*03:01 (OR = 12.6; 95% CI = 1.51–105.0; p < 0.003). Sepsis patients with pneumonia and alleles and DRB1 04:01; 07:01, DQB1 02:01 had the highest mortality rate. Undoubtedly, our preliminary data showed that development of sepsis can be associated with alleles and haplotypes of HLA class II genes. For more precise conclusion the research should be continued to include a larger patient group.

Open access

Anatolijs Požarskis and Aivars Lejnieks

Abstract

Late-onset hypogonadism (LOH) is a clinical and biochemical syndrome associated with age and featured by typical symptoms and reduced blood testosterone level. Among males aged over 30 years, the incidence of androgen deficiency is 7 to 30%. The aim of this study was to investigate the incidence of hypogonadism in patients aged over 40 years with an underlying condition and/or a comorbidity, such as arterial hypertension, Chronic obstructive pulmonary disease (COPD), metabolic syndrome, Type 2 of diabetes mellitus, dyslipidaemia, adiposity in various General practice (GP) and physician-sexologists’ offices in Latvia, and to determine the influence of chronic diseases on the development of hypogonadism. Males aged 39 years who turned to family doctors at nine GP were offered to fill in Aging Male Study (AMS) questionnaires used for the diagnostics of late-onset hypogonadism. Males aged 40 years who visited the office of the physician sexologist Anatolijs Požarskis were offered to fill in the same questionnaires. After compiling the data from AMS questionnaires, a group of males exhibiting signs of LOH were isolated (in total 1222 persons). In these patients, we determined blood testosterone and sex-hormone binding globulin (SHBG) levels. Chronic diseases were found in these men in data evaluation of patient medical records, and after performing physical and laboratory examinations. Late-onset hypogonadism was laboratory-diagnosed in 79% of patients with signs of late-onset hypogonadism in accordance with the AMS questionnaires and with concomitant diseases and in 4.7% of patients with signs of late-onset hypogonadism in accordance with the AMS questionnaires and without the aforementioned concomitant diseases. Persons with arterial hypertension, dyslipidaemia, adiposity, metabolic syndrome, COPD and Type 2 of diabetes mellitus had higher chance of developing hypogonadism (p < 0.001). Arterial hypertension, dyslipidaemia, adiposity, metabolic syndrome, COPD statistically significantly (p < 0.001) decreased the level of total testosterone by 0.47, 1.18, 0.36, 0.67, and 0.18 ng/ml, respectively, and decreased the level of free testosterone by 2.52, 2.71, 1,69, 6.77, and 4.58 pg/ml, respectively. Type 2 diabetes mellitus had no statistically significant effect on the level of total and free testosterone (p = 0.95, p = 0.10). The most significant decrease in the level of testosterone was observed in cases of dyslipidemia, COPD and metabolic syndrome. General physicians should pay special attention to patients with this disease, as these patients belong to a group with a high risk of development of expressed LOH syndrome.

Open access

Aldis Strēlnieks, Alberts Bērziņš, Māra Karakone, Irina Pupkeviča, Kristīne Jubele, Maija Vikmane, Sandis Sakne, Oskars Kalējs and Aivars Lejnieks

Abstract

Patients with atrial fibrillation are faced with an increased risk of thromboembolic events, myocardial infarction, chronic heart failure and death. For some patients with atrial fibrillation, direct current cardioversion (DCCV) is a strategy that can be used to reacquire sinus rhythm. Our aim was to analyse the most commonly used medications after an electrical cardioversion, the reasons for not using them, the effects of pharmacotherapy on recurrence rates, and compare results with data from studies in 2014. The prospective study includes patients with electrocardiographically confirmed atrial fibrillation who underwent direct current cardioversion, hospitalised at Pauls Stradiņš Clinical University Hospital (Rīga, Latvia). The average age was 64.6 years. 50% of the patients were female. During the six-month study period, 14.3% patients were using amiodarone, 8.3% patients were on etacizine, 7.1% received propafenone, and 57.1% used beta blockers in monotherapy or in combination. Warfarin was used in 28.0% patients, direct oral anticoagulants (DOAC’s) in 29.9%, 21,4% of patients received aspirin and 16.7% did not use any antithrombotic therapy. Comparing the recurrence rate in patients using different antiarrhythmic drugs, amiodarone showed a statistically significant superiority compared to etacizine and propafenone (p = 0.02). The obtained data showed that over four years, the use of anticoagulants increased by 11.6%.

Open access

Jurijs Markovs, Agate Galuza, Ivars Melderis, Džanna Krūmiņa and Gundega Knipše

Abstract

Histogenesis and organogenesis in mammals normally transpires in a hypoxic environment. Oxygen diffusing capacity is dependent on diffusion distance, which may vary with the thickness of placental barrier and with the level of tissue vascularity. Since the epidermis is avascular, its development fully depends on dermal blood vessels. Despite the large number of studies focusing on uteroplacental circulation and embryogenesis, it is clear that the current knowledge of how placental changes in pregnancy contribute to skin development is incomplete. The aim of this study was to evaluate the association between structural changes in the placental barrier and development of the integumentary system, with special reference to dermal angiogenesis. The study included specimens of six embryos and ten foetuses from 5 to 24 developmental weeks, and 21 specimens of placental tissue 6–40 weeks gestational age. The panel of antibodies used was S- 100, SMA, CD31, CD34, AE1/AE3 (PCKT), CKRT7, CD 56 and hCG. During the first trimester, maternal blood flow to the placenta appears to be initially restricted by trophoblast plugs. Natural killer cells appear in great abundance in subendothelium of decidual blood vessels, potentially stimulating extensive angiogenesis. By the end of the first trimester, new capillary beds organise to supply the developing epidermal derivatives. During the second trimester, the placental barrier becomes progressively thinner, and uteroplacental circulation is established due to dissolution of endovascular trophoblast plugs. Progression of the formation of skin appendages, hypodermal adipose tissue, demarcation of papillary and reticular dermis, and keratinisation of interfollicular epidermis in the second trimester strongly accompanies the dermal angiogenesis and placental maturation.

Open access

Gurakuç Kuçi

Abstract

The end of the Cold War changed the world order. This change created opportunities for a short time to have an international hegemony to switch to international polycentrism. Huntington had anticipated and explained a confrontation and remake of the international order. This author explains that Islam as a civilization does not have a core state like other civilizations. Turkey today is one of these countries which is trying to take this role of the core state for Islamic civilization. The creation of the core state for Islamic civilization, and the making of all world civilizations with core states, pushed the world into the “civil-centrism” international detachment. However, Turkey as a core for Islam civilization, to the nuclearisation of Turkey can be done with the blessing and assistance of the “West”. Creating these civil-centrist centres also makes it possible to achieve peace and agreements in the global interest more easily.

Open access

Ekaterina N. Baranova, Marat R. Khaliluev, Svetlana G. Spivak, Lilia R. Bogoutdinova, Valery N. Klykov, Olga G. Babak, Dmitry G. Shpakovski, Alexander V. Kilchevsky, Elena K. Shematorova and George V. Shpakovski

Abstract

Recently we have showed that the expression of the mammalian CYP11A1 cDNA in plants confers their resistance to abiotic and biotic stresses. To determine the role of heterologous expression of cytochrome P450scc cDNA in resistance to ROS (radical oxygen species) dependent abiotic stresses, the structural changes of mitochondria and peroxisomes were studied under 150 mM NaCl-induced 14-day salinity treatment on juvenile tobacco plants in in vitro culture. Ultrastructural analysis of mesophyll cells of transgenic tobacco leaves constitutively expressing CYP11A1 cDNA was performed. Under NaCl stress, a change in shape from rounded to elon-gated, reduced section area, formation of branched mitochondria, as well as the emergence of triangular and rhomboid cristae, densification of a mitochondrial matrix, increase in density of contrasting membranes and their thickness were observed in non-transgenic plants. Transgenic plants without stress applied had mitochondria with rounded and elongated shape, twice as small as in non-transgenic plants, with a dense matrix and sinuous cristae. Surprisingly, the effect of NaCl led to increase in size of mitochondria by 1.5 times, decomposition of matrix and the emergence in organelles of light zones presumably containing mitochondrial DNA strands. Thus, the structural organisation of transgenic plant mitochondria under salinity treatment was comparable to that of non-transgenic plants under native conditions. It was also noted that the transgenic plant peroxisomes differed in non-transgenic tobacco both in normal condition and under the action of NaCl. The observed differences in ultrastructural organisation of mitochondria not only support our earlier notion about successful incorporation of the mature P450scc into this organelle, but for the first time demonstrate that the mammalian CYP11A1 signal peptide sequence could be efficiently used in the formation of targeted mitochondria protection of plants from salinity-induced damage.