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Effect of Knee Compression on Kinetic Variables During Vertical Jumps

Abstract

The purpose of this study was to determine how knee compression affected kinetic variables during vertical jumps. Ten healthy males, age 20s, performed a single maximum vertical jump and a ten-consecutive vertical jump trial without knee compression (control condition) and with knee compression. The collected data of ground reaction force were used to analyse the vertical jump height (VJH), peak active force (PAF), decay rate (DR), peak passive force (PPF), loading rate (LR), and the coefficient of variation (CV). During a maximum vertical jump, knee compression increased the magnitudes of DR, PAF, and VJH by 19.8%, 3.41%, and 4.87%, respectively, compared to those under a control condition. During ten consecutive vertical jumps, PAF and VJH showed statistically significant difference according to the repetition count. Also, the mean and CV of PAF, DR, LR, and VJH over consecutive jumps were higher in magnitude under knee compression condition than under the control condition.

Open access
Genetic Diversity of Liparis loeselii in Latvia

Abstract

According to the Global Strategy for Plant Conservation, 75% of endangered species should be preserved in ex situ collections till 2020. The genus Liparis has a lot of recognised taxons, but only one species, Liparis loeselii (L.) Rich., grows in Europe. L. loeselii is a rare and endangered orchid species occurring in Europe. In Latvia L. loeselii is classified as the third category of endangered and protected species. To develop the best conservation strategy, the knowledge concerning the genetic differences of protected plants in a particular area is crucial. For this purpose, the genetic diversity of L. loeselii populations from different Latvian habitats was tested. The inter-retrotransposon amplified polymorphism method (iPBS) was used for population genetic diversity evolution. In total, 54 accessions from nine habitats were collected and analysed. L. loeselii leaves have a high content of phenols that reduce the quality of extracted DNA. It was found that the percentage of polymorph loci varied among the populations of L. loeselii growing in different habitats; some of the populations were genetically homogeneous. The genetic diversity levels of L. loeselii populations are related with the population age and the growing conditions.

Open access
Identification of Glu-A1 and Glu-D1 High Molecular Weight Glutenin Subunits of Common Wheat (Triticum aestivum L.) Using Genetic Markers

Abstract

High molecular weight glutenin subunits (HMW-GS) of wheat are important factors in the determination of bread-making quality. They are responsible for elasticity and polymer formation of wheat dough. In the present study, 43 winter and 40 spring common wheat (Triticum aestivum L.) cultivars originated from Estonia, Belarus, Finland, Denmark, France, Germany, the Great Britain, Latvia, Lithuania, the Netherlands, Norway, Poland, Russia, Sweden, and New Zealand were characterised for Glu-A1 and Glu-D1 allelic composition using PCR method. Analyses were conducted with one DNA marker for identification of Glu-D1 allele encoding subunit Dx5, three DNA markers for Glu-A1 Ax1, Ax2* and AxNull subunits. It was determined that 32 (74.4%) winter and 35 (83.3%) spring cultivars had allele Glu-D1d, and 23 (53.5%) winter and 33 (78.6%) spring — Glu-A1a or Glu-A1b alleles, which have positive effect on dough properties. Polymorphism at Glu-A1 locus was detected in 15 cultivars, and 9 cultivars were polymorphic for locus Glu-D1. The obtained results were compared with published SDS-PAGE data. Complete or partial agreements were found for 78.1% of Glu-A1 and 70.6% of Glu-D1 alleles. Rapid and accurate identification of wheat Glu-1 alleles by molecular markers can be used for selection of wheat genotypes with good bread-making potential.

Open access
Lack of Association Between Rs2067474 Polymorphism in the Histamine Receptor H2 Gene and Gastric Cancer In Latvian Population

Abstract

Histamine has an important role in the process of the gastric mucosa inflammation acting via histamine receptor H2 (encoded by the gene HRH2). Single nucleotide polymorphism of the enhancer element of HRH2 gene promoter rs2067474 (1018G>A)may be associated with changes of expression of the receptor. We attempted to clarify the association of this polymorphism with gastric cancer and/or atrophic gastritis in the Latvian (Caucasian) population. The study group consisted of 121 gastric cancer patients and 650 patients with no evidence of gastric neoplasia on upper gastrointestinal endoscopy. Genotyping for rs2067474 was performed with the TaqMan probe-based system using a commercially available probe for RT-PCR. The frequency of the A allele in the gastric cancer group was 0.41% and in the control group — 1.54% (p = 0.231). No significant differences were found comparing genotypes between gastric cancer versus control patients (OR = 0.236, CI95% = 0.030–1.896), patients with (n = 165) versus without (n = 485) gastric metaplastic lesions (OR = 0.854, CI95% = 0.288–2.540) and patients with (n = 297) and without (n = 353) gastric atrophic lesions (OR = 1.145, CI95% = 0.451–2.906). Our findings suggest that the HRH2 -1018G>A polymorphism (rs2067474) is neither associated with gastric cancer nor the grade of atrophic gastritis in the Latvian (Caucasian) population.

Open access
Targeted Protection of Mitochondria of Mesophyll Cells in Transgenic CYP11A1 CDNA Expressing Tobacco Plant Leaves After NaCl-Induced Stress Damage

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.

Open access
Type 2 Diabetes Mellitus, Impaired Glucose Tolerance and Associated Comorbidities in Children During 2002–2013 in Children’s Clinical University Hospital, Latvia

Abstract

The world has seen a rise of type 2 diabetes mellitus in children during the last 20 years. It is proposed that this increase is due to unhealthy eating habits, increasing obesity, especially among teenagers, and better diagnostics. The main risks associated with diabetes are microvascular and macrovascular complications, which can lead to early disability and premature death. The aim of our study was to identify children with type 2 diabetes mellitus or impaired glucose tolerance and investigate associated comorbidities at the time of diagnosis in the Children’s Clinical University Hospital in Latvia. A retrospective analysis was performed of all children with type 2 diabetes mellitus or glucose tolerance impairment from 2002 till 2013, who were treated in Children’s Endocrinology Centre. According to inclusion criteria, 57 patients were selected of whom 24 (42%) had type 2 diabetes mellitus and 33 (58%) had impaired glucose tolerance. Body mass index was analysed according to percentile and all patients were found to have excess weight. In children with type 2 diabetes mellitus, all patients had body mass index over the 99th percentile. Arterial hypertension was found in 66.7% and dyslipidemia in 54.2% type 2 diabetes mellitus patients. From all type 2 diabetes mellitus patients, 71% (n = 17) were girls and they had statistically significantly higher total cholesterol (p = 0.02) and low-density lipoprotein (p = 0.003) levels. Considering, that girls with type 2 diabetes mellitus have high cardiovascular risk in adulthood, it is very important not only to achieve normal glucose levels early, but also to treat comorbidities, to reduce further microvascular and macrovascular complication risk.

Open access
Higher Speed of Yeast Adherence in Comparison with Speed of Bacteria Adherence to Silica Microparticles

Abstract

The current study explored the possibility to attach bacteria and yeasts to micro-silica particles. The aim of the study was to determine possible differences in the speed of rates of turbidity (or speed of adherence) between suspensions of bacteria and yeasts with and without silica micro-particles. Some important findings were demonstrated, which might be promising for developing of a new diagnostic approach to distinguish bacteria from yeasts. Addition of SiO2 beads to bacterial suspensions resulted in a significantly faster decrease of turbidity rates in comparison with corresponding suspensions without SiO2 beads. However, yeasts adhered to silica micro particles quicker in comparison with the speed of adherence of bacteria to silica.

Open access
Ignoring Digital Templating Leads to Prosthetic Overhang in Total Knee Replacement

Abstract

Published studies on the accuracy of digital templating in total knee replacement (TKR) have employed standard knee, but not hip-to-ankle radiographs. A retrospective study was conducted in our hospital on patients undergoing TKR due to osteoarthritis in a period of six consecutive months. Templating was performed using a calibrating 25 mm metallic ball and Agfa Orthopaedic Tools software by a surgeon not involved with the operation. The surgeon performing the templating was blinded to the size of the implants inserted. Postoperative knee anteroposterior and lateral radiographs were then checked for the presence of prosthetic overhang of ≥ 3 mm. In total, 132 Caucasian adults were included in the study. Femoral overhang occurred in 33%, whereas tibial overhang in only 6% of cases. The exclusion of prosthetic overhang cases significantly improved the accuracy of size detection; exact match for femur increased from 55% to 69%, and for tibia from 70% to 73%. All implants were predicted to within one size in all cases. Digital templating using a calibrating 25 mm metallic ball, Agfa Orthopaedic Tools software and hip-to-ankle and knee lateral radiographs is an accurate method of predicting the knee implant to within one size. Ignoring this procedure leads to prosthetic overhang.

Open access
The Importance of Cyclin D1, P53, Cd56 Antigen Expression in Plasma Cells and its Correlation with Serological and Clinical Parameters in Patients with Multiple Myeloma

Abstract

CD56, p53, and Cyclin D1 detection in plasma cells (PC) can help to predict prognosis of multiple myeloma (MM). Clinical and biochemical prognostic parameters were analysed in a group of 122 patients with primary diagnosed MM in the period 2011–2015. Bone marrow biopsies were analysed with Cyclin D1, p53, CD56 antibodies. Statistical analysis was performed using Microsoft Excel 2010 and Graph Pad Prism 5. Lack of CD56 expression and p53-positivity were significantly correlated with a low glomerular filtration rate (GFR), low platelet count and haemoglobin level, as well as with high serum creatinine levels. Patients with Cyclin D1 expression in PC had a significantly higher serum calcium level and more common osteolytic lesion in bones. CD56-negative as well as p53, Cyclin D1-positive groups had advanced Salmon–Durie MM stages by and significantly higher ß2-microglobulin. Expression of p53, Cyclin D1 and lack of CD56 antigen in PC are negative predictive factors in cases of MM, as these patients were diagnosed as having late Salmon–Durie stage and higher ß2-microglobulin level. Expression of p53 and lack of CD56 antigen in PC is associated with an increased creatinine level in blood and decreased GFR; therefore, these are criteria for chronic renal failure progression and poorer prognosis of MM.

Open access