Coronary Artery Calcification,Epicardial Fat Burden,and Cardiovascular Events in Chronic Obstructive Pulmonary Disease

RationalePatients with chronic obstructive pulmonary disease (COPD) suffer from significantly more cardiovascular comorbidity and mortality than would be anticipated from conventional risk factors. The aim of this study was to determine whether COPD patients have a higher coronary artery calcium score (CACS) and epicardial fat burden, compared to control subjects, and their association with cardiovascular events.MethodsFrom a registry of 1906 patients 81 patients with clinically diagnosed COPD were one-to-one matched to 81 non-COPD control subjects with a smoking history, according to their age, sex, and the number of classic cardiovascular risk factors (arterial hypertension, diabetes mellitus, dyslipidemia, family history of premature coronary artery disease). CACS, epicardial fat, and subsequent major adverse cardiovascular events (MACE) during follow-up were compared between groups.ResultsPatients with COPD (Global Initiative for Chronic Obstructive Lung Disease-classification I: 5%, II: 23%, III: 16% and IV: 56%) showed no difference in CACS (median difference 68 Agatston Units [95% confidence interval -176.5 to 192.5], p=0.899) or epicardial fat volume (mean difference -0.5 cm³ [95% confidence interval -20.9 to 21.9], p=0.961) compared with controls. After a median follow-up of 42.6 months a higher incidence of MACE was observed in COPD patients (RR=2.80, p=0.016) compared with controls. Cox proportional hazard regression identified cardiac ischemias and CACS as independent predictors for MACE.ConclusionCOPD patients experienced a higher MACE incidence compared to controls despite no baseline differences in coronary calcification and epicardial fat burden. Other mechanisms such as undersupply of medication seem to account for an excess cardiovascular comorbidity in COPD patients.     

Computational and mutational analysis of TatD DNase of Bacillus anthracis

The role of TatD DNases as DNA repair enzymes or cell death (apoptotic) nucleases is well established in prokaryotes as well as eukaryotes. The current study aims to characterize the TatD nuclease from Bacillus anthracis (Ba TatD) and to explore its key histidine catalytic residues. Ba TatD was found to be a metal-dependent, nonspecific endonuclease which could efficiently cleave double-stranded DNA substrates. Moreover, Ba TatD nuclease was observed to be thermostable up to 55°C and act in a wide pH range indicating its industrial applicability. Diethyl pyrocarbonate-based histidine-selective alkylation of the Ba TatD resulted in a loss of its nuclease activity suggesting a crucial role of the histidine residues in its activity. The key residues of Ba TatD were predicted using sequence analysis and structure-based approaches, and then the predicted residues were further tested by mutational analysis. Upon mutational analysis, H128 and H153 have been found to be crucial for Ba TatD activity, though H153 seems to bear an important but a dispensable role for the Ba TatD nuclease. Ba TatD had a uniform expression in the cytosol of B. anthracis, which indicates a significant role of the protein in the pathogen's life cycle. This is the first study to identify and characterize the TatD DNase from B. anthracis and will be helpful in gaining more insights on the role of TatD proteins in Gram-positive bacteria where it remains unexplored.     

Does Iris Change Over Time?

Iris as a biometric identifier is assumed to be stable over a period of time. However, some researchers have observed that for long time lapse, the genuine match score distribution shifts towards the impostor score distribution and the performance of iris recognition reduces. The main purpose of this study is to determine if the shift in genuine scores can be attributed to aging or not. The experiments are performed on the two publicly available iris aging databases namely, ND-Iris-Template-Aging-2008–2010 and ND-TimeLapseIris-2012 using a commercial matcher, VeriEye. While existing results are correct about increase in false rejection over time, we observe that it is primarily due to the presence of other covariates such as blur, noise, occlusion, and pupil dilation. This claim is substantiated with quality score comparison of the gallery and probe pairs.     

Barriers to folding of the transmembrane domain of the Escherichia coli autotransporter adhesin involved in diffuse adherence

Adhesin involved in diffuse adherence (AIDA) is an autotransporter protein that confers the diffuse adherence phenotype to certain diarrheagenic Escherichia coli strains. It consists of a 49 amino acid signal peptide, a 797 amino acid passenger domain, and a 440 amino acid beta-domain integrated in the outer membrane. The beta-domain consists of two parts: the beta(1)-domain, which is predicted to form two beta-strands on the bacterial cell surface, and the beta(2)-domain, which constitutes the transmembrane domain. We here present a detailed biophysical analysis of the AIDA beta-domain addressing its refolding properties and its different conformational states and their stability. We find that the beta(2)-domain in solution can fold only when the beta(1)-domain is present and only with 50% efficiency. However, 100% refolding of the beta(2)-domain, with or without the beta(1)-domain, can be achieved in the presence of a solid support. Folding can only take place above the cmc of the detergent used, but the refolded state is retained if diluted below the cmc, revealing a kinetic barrier to dissociation of the detergent molecules from the folded protein. Refolding attempts of the beta(2)-domain in the absence of a solid support result in the formation of an oligomeric misfolded state both in the absence and in the presence of detergent. Despite being misfolded, these states unfold cooperatively with a T(m) approximately 70 degrees C. The refolded protein in the nonionic detergent octylpolyoxyethylene (oPOE) can only be thermally unfolded in the presence of SDS. The linear relationship between SDS mole fraction and unfolding temperature, T(m), predicts a T(m) of 112.9 +/- 1.2 degrees C for the beta(2)-domain and 132.7 +/- 12.2 degrees C for the entire beta-domain in pure oPOE. Thus, the beta(1)-domain also stabilizes the beta(2)-domain. In conclusion, our data show that the in vitro refolding of the AIDA beta-domain is critically dependent on a solid support, suggesting that in vivo specific biological factors may assist in folding the protein correctly into the outer membrane to avoid the formation of stably misfolded conformations.     

Differential distribution of pigment-protein complexes in the Thylakoid membranes of Synechocystis 6803

Thylakoids in Synechocystis 6803, though apparently uniform in appearance in ultrastructure, were found to consist of segments which were functionally dissimilar and had distinct proteomes. These thylakoid segments can be isolated from Synechocystis 6803 by successive ultracentrifugation of cell free extracts at 40,000×g (40?k segments), 90,000×g (90?k segments) and 150,000×g (150?k segments). Electron microscopy showed differences in their appearance. 40?k segments looked feathery and fluffy, whereas the 90?k and 150?k thylakoid membrane segments appeared tiny and less fluffy. The absorption spectra showed heterogeneous distribution of pigment-protein complexes in the three types of segments. The photochemical activities of Photosystem I (PSI) and Photosystem II (PSII) showed unequal distributions in 40?k, 90?k and 150?k segments which were substantiated with low temperature fluorescence measurements. The ratio of PSII/PSI fluorescence emission at 77?K (λ(ex)?=?435?nm) was highest in 150?k segments indicating higher PSII per unit PSI in these segments. The chlorophyll fluorescence lifetimes in the membranes, determined with a time-correlated single-photon counting technique, could be resolved in three components: τ(1) (=)?<40?ps, τ(2) (=)?425-900?ps and τ(3) (=)?2.4-3.2?ns. The percentage contribution of the fastest component (τ(1)) decreased in the order 40?k?>?90?k?>?150?k segments whereas that of the other two components showed a reversed trend. These studies indicated differential distribution of pigment-protein complexes in the three membrane segments suggesting heterogeneity in the thylakoids of Synechocystis 6803.     

Fungicide impacts on photosynthesis in crop plants

Fungicides are widely used to control pests in crop plants. However, it has been reported that these pesticides may have negative effects on crop physiology, especially on photosynthesis. An alteration in photosynthesis might lead to a reduction in photoassimilate production, resulting in a decrease in both growth and yield of crop plants. For example, a contact fungicide such as copper inhibits photosynthesis by destroying chloroplasts, affecting photosystem II activity and chlorophyll biosynthesis. Systemic fungicides such as benzimidazoles, anilides, and pyrimidine are also phytotoxic, whereas azoles stimulate photosynthesis. This article focuses on the available information about toxic effects of fungicides on photosynthesis in crop plants, highlighting the mechanisms of perturbation, interaction, and the target sites of different classes of fungicides.     

Probiotic Potential of the Farmed Olive Flounder,Paralichthys olivaceus,Autochthonous Gut Microbiota

In recent years, considerable and growing attention has been given to the application of host-associated microorganisms as a more suitable source of probiotics in aquaculture sector. Herein, we isolated and screened the olive flounder gut microbiota for beneficial bacterial strains that might serve as potential probiotics in a low fishmeal extruded aquafeed. Among the ten identified isolates, Bacillus amyloliquefaciens SK4079 and B. subtilis SK4082 were screened out based on their heat-resistant ability as well as enzymatic and non-hemolytic activities. Although both strains were well able to utilize carboxymethyl cellulose (CMC), xylan, and soybean meal (SBM) as a single carbon source in the minimal nutrient M9 medium, B. subtilis exhibited significantly higher cellulase, xylanase, and protease activities than B. amyloliquefaciens. The two selected strains were well able to degrade the undesirable anti-nutritional component of the SBM, which would limit its utilization as protein source in aquafeed industry. Significantly higher biofilm formation capacity and notably stronger adhesive interactions with the flounder’s skin mucus were detected in B. subtilis than B. amyloliquefaciens. Immobilization of the spores from the selected strains, in a SBM complex carrier, remarkably enhances their thermal resistance at 120 °C for 5 min and different drying conditions. It was also interesting to learn that the B. subtilis spores could survive and remain viable after being sprayed onto extruded low-fish meal feed pellets for as long as 6 months. Overall, the findings of the present study could help the food/feed industries achieve their goal of developing cost-effective yet efficient products.

     

Novel nuclear translocation of inositol polyphosphate 4-phosphatase is associated with cell cycle,proliferation and survival

Inositol polyphosphate 4 phosphatase type I enzyme (INPP4A) has a well-documented function in the cytoplasm where it terminates the phosphatidylinositol 3-kinase (PI 3-K) pathway by acting as a negative regulator. In this study, we demonstrate for the first time that INPP4A shuttles between the cytoplasm and the nucleus. Nuclear INPP4A is enzymatically active and in dynamic equilibrium between the nucleus and cytoplasm depending on the cell cycle stage, with highest amounts detected in the nucleus during the G₀/G₁ phase. Moreover, nuclear INPP4A is found to have direct proliferation suppressive activity. Cells constitutively overexpressing nuclear INPP4A exhibit massive apoptosis. In human tissues as well as cell lines, lower nuclear localization of INPP4A correlate with cancerous growth. Together, our findings suggest that nuclear compartmentalization of INPP4A may be a mechanism to regulate cell cycle progression, proliferation and apoptosis. Our results imply a role for nuclear-localized INPP4A in tumor suppression in humans.