Sequence requirements in the catalytic core of the "10-23" DNA enzyme

A systematic mutagenesis study of the "10-23" DNA enzyme was performed to analyze the sequence requirements of its catalytic domain. Therefore, each of the 15 core nucleotides was substituted separately by the remaining three naturally occurring nucleotides. Changes at the borders of the catalytic domain led to a dramatic loss of enzymatic activity, whereas several nucleotides in between could be exchanged without severe effects. Thymidine at position 8 had the lowest degree of conservation and its substitution by any of the other three nucleotides caused only a minor loss of activity. In addition to the standard nucleotides (adenosine, guanosine, thymidine, or cytidine) modified nucleotides were used to gain further information about the role of individual functional groups. Again, thymidine at position 8 as well as some other nucleotides could be substituted by inosine without severe effects on the catalytic activity. For two positions, additional experiments with 2-aminopurine and deoxypurine, respectively, were performed to obtain information about the specific role of functional groups. In addition to sequence-function relationships of the DNA enzyme, this study provides information about suitable sites to introduce modified nucleotides for further functional studies or for internal stabilization of the DNA enzyme against endonucleolytic attack.     

Deletion analysis in the catalytic region of the 10-23 DNA enzyme

In this study, the functional relevance of the core nucleotides of the RNA cleaving 10-23 DNA enzyme (DNAzyme) was investigated. Systematic deletion studies revealed that DNAzymes lacking thymine at position 8 (T8) retain catalytic activity comparable to that of the wild-type enzyme. Deletion of the adjacent cytosine at position 7 (C7) also resulted in a highly active enzyme and even the double deletion mutant C7/T8 displayed cleavage activity, although the catalytic rate under multiple turnover conditions was found to be reduced by one order of magnitude. The identification of non-essential nucleotides in the catalytic core might help to stabilize the DNAzyme against nucleolytic degradation and to overcome problems in elucidating its three-dimensional structure.     

Increased percentage of CD8+CD28- T cells correlates with clinical activity in primary Sjögren's syndrome

The role of CD28- T cell subpopulations in primary Sj?gren's syndrome (pSS) has become controversial. Changes in the number of CD28- T cells have been demonstrated in autoimmune diseases in co-existence with Sj?gren's syndrome. The study aimed to indicate differences in the number of CD4+CD28- and CD8+CD28- T cells in patients with sicca syndrome and suspected pSS. Thirty patients with sicca syndrome at baseline were studied and followed up for 5months. After final diagnosis, comparison was made of the previously recorded lymphocyte subpopulations in patients with pSS and those in other defined subgroups. Notably high percentages of CD8+CD28- T cells were indicated in pSS patients, which correlated with the severity of the sicca symptoms and cutaneous and muscular systemic disease activity. Changes in CD8+CD28- T cell percentages may thus assist in the early differential diagnosis of pSS patients from those with similar clinical symptoms.     

Plant Aurora kinases play a role in maintenance of primary meristems and control of endoreduplication

? The conserved family of Aurora kinases has multiple functions during mitosis. The roles of plant Aurora kinases have been characterized using inhibitor treatments. ? We down-regulated Aurora kinases in Arabidopsis thaliana using RNA interference (RNAi). We carried out a detailed phenotypic analysis of Aurora RNAi plants, biochemical and microscopic studies of AtAurora1 kinase together with AtTPX2 (targeting protein for Xklp2) and γ-tubulin. ? Cell division defects were observed in plants with reduced expression of Aurora kinases. Furthermore, the maintenance of primary meristems was compromised and RNAi seedlings entered endoreduplication prematurely. AtAurora1, its activator AtTPX2, and γ-tubulin were associated with microtubules in vitro; they were attached to regrowing kinetochore microtubules and colocalized on spindle microtubules and with a subset of early phragmoplast microtubules. Only the AtAurora1 kinase was translocated to the area of the cell plate. ? RNAi silencing of Aurora kinases showed that, in addition to their function in regulating mitosis, the kinases are required for maintaining meristematic activity and controlling the switch from meristematic cell proliferation to differentiation and endoreduplication. The colocalization and co-fractionation of AtAurora1 with AtTPX2, and γ-tubulin on microtubules in a cell cycle-specific manner suggests that AtAurora1 kinase may function to phosphorylate substrates that are critical to the spatiotemporal regulation of acentrosomal microtubule formation and organization.     

Plasma concentrations of amino acid and nicotinamide metabolites in rheumatoid arthritis – potential biomarkers of disease activity and drug treatment

This study aimed to evaluate changes in plasma amino acid and nicotinamide metabolites concentrations in rheumatoid arthritis (RA) in a search for potential biomarkers of the disease activity and the effect treatment. Analysis of plasma metabolite patterns with liquid chromatography/mass spectrometry revealed specific changes in RA as well as correlations with clinical parameters. Combined concentration parameter calculated as [aspartic acid]?+?[threonine]?+?[tryptophan]???[histidine]???[phenylalanine] offered the strongest correlation (p?<?0.001) with pain joint count, swollen joint count and DAS 28. Such analysis of amino acid and related metabolite pattern offers potential for diagnosis as well as for monitoring disease progression and therapy in RA.     

Prevalence and spatiotemporal distribution of African swine fever in Lithuania, 2014–2017

Background

The emergence in 2014 and persistence of African Swine Fever (ASF) in Lithuania has been linked to infected wild boar movement and close contact with the carcasses of other infected wild boars. Over time the number of reported cases of ASF in wild boars gradually increased, but no detailed epidemiological data has been available. Therefore, the objective of the present study was to determine ASF virus prevalence in wild boars and domestic pigs during the 2014–2017 period and further explore the current geographical distribution of the virus.

Results

Our study results show that ASF virus prevalence in hunted wild boars using PCR analysis increased from 0.83% (95% CI 0.69–0.98) to 2.27% (95% CI 2.05–2.48) from 2014 to 2016 respectively. However, there was a dramatic jump in the number of ASF positive wild boars cases in 2017 resulting in prevalence of 12.39% (95% CI 11.91–12.86) (p <?0.05).The average prevalence of ASF-specific antibodies in wild boar population during years 2014–2017 was 0.45% (95% CI 0.39–0.51) based on ELISA test results.Prevalence of ASF virus in domestic pigs ranged from 0.24% (95% CI 0.17% - 0.32) in 2015 to 2.74% (95% CI 2.33% - 3.15) in 2017. The average seasonal prevalence of ASF virus in pigs was statistically significant (p?<?0.05) and ranged from 0% in spring to 3.68% (95% CI 3.32–4.05) in summer. Correlation between the pig density and number of recorded pig ASF cases in affected regions was only found in 2017 (R =?0.78, p?<?0.05). No correlation was detected between the wild boar density and number of recorded pig or wild boar ASF - positive cases.

Conclusions

This study provides the first results of ASF virus prevalence changes in Lithuania during the 2014–2017. The overall results confirm the relatively high prevalence of ASF virus in wild boar that was gradually increasing from 2014 to 2017. In the last year of study, the number of ASF positive cases in both domestic pigs and wild boars had unexpectedly increased several times. A better understanding of current status of the disease will enable better control and prevent further spread of ASF virus in Western Europe.

     

Sexual dimorphism in chin shape: implications for adaptive hypotheses

The chin, or mentum osseum, is one of the most distinctive anatomical traits of modern humans. A variety of hypotheses for the adaptive value of the chin have been proposed, ranging from mechanical stress resistance to sexual selection via mate choice. While the sexual selection hypothesis predicts dimorphism in chin shape, most biomechanical hypotheses preclude it. Therefore determining the presence or absence of significant sexual dimorphism in chin shape provides a useful method for differentiating between various adaptive hypotheses; however, this has yet to be done due to a lack of quantitative data on chin shape. The goals of this study are therefore: (1) to introduce a new method for quantifying chin shape and (2) to determine the presence or absence of sexual dimorphism in chin shape in a diverse sample of modern humans. Samples were drawn from recent human skeletal collections representing nine geographic regions. Outlines of mentum osseum contours were quantified using elliptical Fourier function analysis (EFFA). Fourier coefficients were analyzed using principal components analysis (PCA). Sexual dimorphism in chin shape was assessed using PC loadings in the pooled geographic sample, and statistically significant differences were found. These findings provide the first quantitative, morphologically based evidence in support of adaptive hypotheses that predict dimorphism in chin shape, including the sexual selection hypothesis.     

Assessing the Sustainability of the Lithuanian Hazardous Waste Management System

Human activities generate waste, whose amounts tend to increase as the demand for quality of life becomes greater and greater. Hazardous waste (HW) generally makes up only about 1% of all waste in Europe; nevertheless, it presents a serious risk to the ecosystem and human health unless managed and treated safely. Several countries of the European Union (EU) report treatment rates of HW in excess of 40%; the others export a large portion of it. Notwithstanding that lots of efforts have been made to properly identify, treat, recycle, store, transport, and dispose of HW, this is still a hot topic faced by the governments of many EU countries. The objective of this article is to present a sustainable indicators system to assist in the implementation of a modern and sustainable hazardous waste management (HWM) system in Lithuania. The specific goals are (1) to promote the development of a comprehensive monitoring and enforcement system for timely implementation of HWM rules and other related pieces of legislation and (2) to assist in the implementation of training and awareness of the programs of HWM in support of the development of background data for policy making, including improvement of a hazardous waste identification scheme. The emphasis is put on preventing future discharges of HW by promoting the actions that will result in avoidance, recycling, or recovery of the otherwise hazardous waste.