Expression, purification and structural analysis of the Pyrococcus abyssi RNA binding protein PAB1135

<p>Abstract</p> <p>Background</p> <p>The gene coding for the uncharacterized protein PAB1135 in the archaeon <it>Pyrococcus abyssi </it>is in the same operon as the ribonuclease P (RNase P) subunit Rpp30.</p> <p>Findings</p> <p>Here we report the expression, purification and structural analysis of PAB1135. We analyzed the interaction of PAB1135 with RNA and show that it binds efficiently double-stranded RNAs in a non-sequence specific manner. We also performed molecular modeling of the PAB1135 structure using the crystal structure of the protein Af2318 from <it>Archaeoglobus fulgidus </it>(<ext-link ext-link-id="2OGK" ext-link-type="pdb">2OGK</ext-link>) as the template.</p> <p>Conclusions</p> <p>Comparison of this model has lead to the identification of a region in PAB1135 that could be involved in recognizing double-stranded RNA.</p

Rice quality profiling to classify germplasm in breeding programs

The objective of this work was to define a quality space for assessing rice varieties. Eleven long grain varieties, seven commercial and four new advanced lines were assessed to obtain complete quality profile considering appearance, physicochemical parameters, water absorption behaviour, pasting profile and textural attributes. Commercial varieties were chosen to provide the widest variation in properties, applying the variability analysis concepts of the Taguchi method, including Japonicas, Indicas, hybrids and aromatics. Quality parameters were measured in five different dimensions of quality space (totalling 50). Variable reduction techniques were applied to chose 3 parameters in each dimension (totalling 15 quality indicators) that would describe the whole space with greatest orthogonality, accuracy and yet explaining a significant proportion of the whole variance of data. The analysis of the quality space thus defined and similarities between varieties is illustrated with the conclusion of how the 4 new advanced lines perform in terms of quality behaviour, where it is concluded that one of them is very promising as an improvement over European (Indica) towards the behaviour of a pure Guyana (Indica), whereas 3 others have significant shortcomings in various aspects of the quality space compared to all others, albeit their greater closeness to Japonicas

Blood flow in a bifurcation and confluence microchannel: effect of the cell-free layer in velocity profiles

A few detailed studies have been performed in complex in vitro microvascular networks composed by bifurcations and confluences. The main purpose of the present work is to numerically simulate the flow of two distinct fluids through bifurcation and confluence geometries, i. e red blood cells (RBCs)suspended in Dextran40 with about 14% of heamatocrit and pure water. The simulations of pure water and RBCs flows were performed resorting to the commercial finite volume software package FLUENT. A well known hemodynamic phenomenon, known as Fahraeus-Lindqvist effect, observed in both in vivo and in vitro studies, results in the formation of a marginal cell-free layer (CFL) at regions adjacent to the wall. Recently, studies have shown that the formation of the CFL is affected by the geometry of the microchannel and for the case of the confluences a CFL tend to appear in the middle of the microchannel after the apex of the confluence. By using the CFL experimental data, the main objective of this work is to implement a CFL in the numerical simulations in order to obtain a better understanding of the effect of this layer on the velocity profiles

Histologic and Histomorphometric Analysis of Posterior Region of the Human Temporomandibular Disc

Objective The aim of this study was to analyze histologic and histomorphometric features of the articular disc in groups with and without disc displacement. Study design A sample of 39 temporomandibular joints TMJs (31 case specimens, 8 control specimens) from 28 patients (mean age 31.2 years) were recruited for this study. The patients were considered to be affected and treated surgically with disc repositioning when presenting painful clinical signs of disc displacement after unsuccessful nonsurgical treatment for at least 6 months. Of the control patients, 4 presented condyle fracture which required opening to be reduced for treatment, and 4 displayed active condyle hyperplasia. The posterior region of the disc was removed and sent for histologic and histomorphometric analysis. Histologic (hematoxylin-eosin) and histomorphometric (picro-Sirius red) analyses were performed. Statistically significant differences between the analyzed groups were accessed through the chi-squared test (P ≤ .05). The Mann-Whitney U test was used to observe the differences between mean values when variables did not present normal distribution [Kolmogorov-Smirnov(a) test]. Results There were no significant differences between the groups in relation to the parameters studied by histologic and histomorphometric analysis (using or not using polarization). Conclusions To the limits of this study, there were no significant histologic and histomorphometric differences in the articular disc between groups with and without TMJ dysfunction

Enzymatic dyeing of wool

This study reports for the dyeing of wool using an enzymatic system comprising laccase (EC 1.10.3.2), dye precursor - 2,5-diaminobenzenesulfonic acid and dye modifiers – cathehol and resorcinol. The effect of the process variables - reaction time, enzyme and modifiers concentration on fabrics colour was studied, according to an appropriate experimental design. Different hues and depth of shades could be achieved varying the concentration of the modifiers and the time of laccase treatment. The duration of the enzymatic reaction appeared to be the most important factor in the dyeing process. Thus the dyeing process, performed at low temperature and mild pH, was advantageous in terms of reduced enzyme and chemicals dosage. The ability of the laccases to generate colour “in situ” from originally non-coloured, low-molecular substances, appears as an alternative to the conventional dyeing processes. The dye precursors can be used alone or in combination with suitable modifier (coupler) – another phenolic compound, which together with the dye precursor will enlarge the colour pallet achieved in the enzymatic dyeing