The g5R (D250) gene of African swine fever virus encodes a Nudix hydrolase that preferentially degrades diphosphoinositol polyphosphates.

The African swine fever virus (ASFV) g5R gene encodes a protein containing a Nudix hydrolase motif which in terms of sequence appears most closely related to the mammalian diadenosine tetraphosphate (Ap4A) hydrolases. However, purified recombinant g5R protein (g5Rp) showed a much wider range of nucleotide substrate specificity compared to eukaryotic Ap4A hydrolases, having highest activity with GTP, followed by adenosine 5'-pentaphosphate (p5A) and dGTP. Diadenosine and diguanosine nucleotides were substrates, but the enzyme showed no activity with cap analogues such as 7mGp3A. In common with eukaryotic diadenosine hexaphosphate (Ap6A) hydrolases, which prefer higher-order polyphosphates as substrates, g5Rp also hydrolyzes the diphosphoinositol polyphosphates PP-InsP5 and [PP]2-InsP4. A comparison of the kinetics of substrate utilization showed that the k(cat)/K(m) ratio for PP-InsP5 is 60-fold higher than that for GTP, which allows classification of g5R as a novel diphosphoinositol polyphosphate phosphohydrolase (DIPP). Unlike mammalian DIPP, g5Rp appeared to preferentially remove the 5-beta-phosphate from both PP-InsP5 and [PP]2-InsP4. ASFV infection led to a reduction in the levels of PP-InsP5, ATP and GTP by ca. 50% at late times postinfection. The measured intracellular concentrations of these compounds were comparable to the respective K(m) values of g5Rp, suggesting that one or all of these may be substrates for g5Rp during ASFV infection. Transfection of ASFV-infected Vero cells with a plasmid encoding epitope-tagged g5Rp suggested localization of this protein in the rough endoplasmic reticulum. These results suggest a possible role for g5Rp in regulating a stage of viral morphogenesis involving diphosphoinositol polyphosphate-mediated membrane trafficking.     

The role of functional single nucleotide polymorphisms of the human glucocorticoid receptor gene NR3C1 in Polish patients with bronchial asthma

N363S and ER22/23EK polymorphisms observed within glucocorticoid receptor gene (NR3C1) may play an important role in the development of bronchial asthma. NR3C1 gene is associated with an altered sensitivity to GCs. The aim of the research project was to study the correlation between this NR3C1 gene polymorphisms and occurrence of asthma in the population of Polish asthmatics. Peripheral blood was obtained from 207 healthy volunteers and 221 asthma patients. Genotyping was carried out with PCR-RFLP method. In the groups of patients with uncontrolled moderate asthma and uncontrolled severe disease, the genotype distribution for the investigated polymorphisms was as follows: N363S-AA, AG, GG occurring with 0.881/0.073/0.046 frequency and ER22/23EK-GG, GA, AA occurring with 0.963/0.037/0.000 frequency. Chi-square analysis revealed a significantly different (P < 0.05) distribution between cases and controls for the N363S polymorphisms. The N363S polymorphism of NR3C1 gene is significantly associated with bronchial asthma, susceptibility to the development of moderate to severe form of uncontrolled bronchial asthma.     

The effects of acute corticosterone administration on anxiety, endogenous corticosterone, and c-Fos expression in the rat brain

The effects of acute pretreatment of rats with corticosterone (5 and 20 mg/kg, s.c.) on emotional behavior, expression of c-Fos protein in brain structures, and serum concentration of corticosterone were studied to model the short-term glucocorticoid-dependent changes in brain functions. Corticosterone was administered 90 min before training of a conditioned fear reaction (a freezing response), and behavioral, hormonal and immunocytochemical effects were examined 1 day later, on the test day. Pretreatment of rats with corticosterone significantly attenuated the freezing reaction in the conditioned fear test. The effect of the corticosterone was accompanied by a selective enhancement of the aversive context-induced c-Fos expression in some brain structures: the parvocellular and magnocellular neurons of the paraventricular hypothalamic nucleus (pPVN and mPVN), the medial amygdala nucleus (MeA), and the cingulate cortex, area 1 (Cg1), as well as an increase in the concentration of aversive context-induced endogenous serum glucocorticoid, 1.5 h and 10 min after the test session, respectively. It is suggested that the behavioral effects of acute pretreatment of rats with corticosterone could be due to changes in the mnemonic processes in the brain, inhibition of brain corticotropin releasing factor (CRF) synthesis, or stimulation of GABA-A receptor modulating neurosteroids synthesis. It is hypothesized that the enhanced activity of Cg1, MeA, pPVN, and mPVN, and the hypothalamic-pituitary-adrenal axis with concomitant increased serum glucocorticoid concentration, might serve to facilitate active coping behavior in a threatening situation.     

Disappearance of differences in antibiotic resistance of Staphylococcus aureus strains isolated in hospitals and in general practice

There is general opinion that Staphylococcus aureus strains isolated in hospitals are more frequently resistant to antibiotics than community strains, however, the increasing resemblance between hospital and community strains has been recently reported. The aim of the study was to compare the antibiotic resistance and phage-type pattern of S. aureus strains isolated from patients treated either in hospitals or in general practice in northern part of Poland. The study was conducted on 771 S. aureus strains isolated from different specimens. Phage typing was performed according to the method of Blair and Williams. The drug susceptibility was determined by the disc-diffusion method. There were no significant differences in antibiotic resistance or phage-type pattern when hospital and community methicillin-sensitive S. aureus (MSSA) strains were compared. The most MSSA were resistant to penicillin (84.6% and 82.1% respectively) and doxycycline (49.3% and 50.4% respectively) whereas they were rarely resistant to other antibiotics. The predominance of phage group II was found in both hospitals (28.0%) and general practice (29.9%). Phage group III, usually associated with hospitals, occurred in small percentage (12.9% and 9.4% respectively) while to this group predominantly (76.6%) multiresistant methicillin resistant S. aureus (MRSA) isolated in hospitals belonged. These results suggest, that there is only slight difference in antibiotic resistance between hospital and community S. aureus strains. Antibiotic resistance pattern mainly results from frequency of appearance of MRSA, mostly occurring in hospitals.     

Binary mixtures of (N-phosphonomethyl)-glycine with new aminophosphonates

The potential biological activity of binary mixtures of some new organophosphorous compounds, aminoalkane- and aminofluorenephosphonates, with (N-phosphonomethyl)-glycine (glyphosate, PMG) was studied. The inhibition of growth of wheat (Triticum aestivum) induced by individual compounds and their equimolar mixtures with PMG was a measure of that activity. The experiments were expected to show if the new compounds exhibited good biological activity to be used for agrochemical applications and if this activity can be improved when they are used in mixtures with glyphosate which is the active component of the well-known herbicide Roundup. The results obtained show that aminofluorenephosphonates inhibited wheat growth when used in micromolar concentrations. Thus, their efficiency can be compared to that of PMG. The efficiency of aminoalkanephosphonates was one order of magnitude weaker. The measure of the efficiency was the effective concentration inhibiting wheat growth by 50% (EC50). The most demanded interaction, i.e., a synergistic was observed for only one of binary mixtures of the compounds studied with PMG. Mostly they showed antagonistic or strong antagonistic interactions. Some of them were of the additive type. Such results exclude the possibility of potential use of all the compounds studied in binary mixtures with phosphonomethylglycine, especially as the mentioned synergistic interaction found was rather weak. The influence of structural features of anminophosphonates on the results obtained is discussed.     

IGFs and IGF-Binding Proteins in the Synovial Fluid of Patients with Rheumatoid Arthritis and Osteoarthritis

International Journal of Peptide Research and Therapeutics - The progressive damage of human articular cartilage is associated with loss of integrity of its extracellular matrix components. Their...     

Estimation of hurdle clearance parameters using a monocular human motion tracking method

This paper presents a method of monocular human motion tracking for estimation of hurdle clearance kinematic parameters. The analysis involved 10 image sequences of five hurdlers at various training levels. Recording of the sequences was carried out under simulated starting conditions of a 110 m hurdle race. The parameters were estimated using the particle swarm optimization algorithm and they are based on analysis of the images recorded with a 100 Hz camera. The proposed method does not involve using any special clothes, markers, inertial sensors, etc. As the quality criteria, the mean absolute error and mean relative error were used. The level of computed errors justifies the use of this method to estimate hurdle clearance parameters.