Involvement of Plasmodium falciparum protein kinase CK2 in the chromatin assembly pathway

<p>Abstract</p> <p>Background</p> <p>Protein kinase CK2 is a pleiotropic serine/threonine protein kinase with hundreds of reported substrates, and plays an important role in a number of cellular processes. The cellular functions of <it>Plasmodium falciparum </it>CK2 (PfCK2) are unknown. The parasite's genome encodes one catalytic subunit, PfCK2α, which we have previously shown to be essential for completion of the asexual erythrocytic cycle, and two putative regulatory subunits, PfCK2β1 and PfCK2β2.</p> <p>Results</p> <p>We now show that the genes encoding both regulatory PfCK2 subunits (PfCK2β1 and PfCK2β2) cannot be disrupted. Using immunofluorescence and electron microscopy, we examined the intra-erythrocytic stages of transgenic parasite lines expressing hemagglutinin (HA)-tagged catalytic and regulatory subunits (HA-CK2α, HA-PfCK2β1 or HA-PfCK2β2), and localized all three subunits to both cytoplasmic and nuclear compartments of the parasite. The same transgenic parasite lines were used to purify PfCK2β1- and PfCK2β2-containing complexes, which were analyzed by mass spectrometry. The recovered proteins were unevenly distributed between various pathways, with a large proportion of components of the chromatin assembly pathway being present in both PfCK2β1 and PfCK2β2 precipitates, implicating PfCK2 in chromatin dynamics. We also found that chromatin-related substrates such as nucleosome assembly proteins (Naps), histones, and two members of the Alba family are phosphorylated by PfCK2α <it>in vitro</it>.</p> <p>Conclusions</p> <p>Our reverse-genetics data show that each of the two regulatory PfCK2 subunits is required for completion of the asexual erythrocytic cycle. Our interactome study points to an implication of PfCK2 in many cellular pathways, with chromatin dynamics being identified as a major process regulated by PfCK2. This study paves the way for a kinome-wide interactomics-based approach to elucidate protein kinase function in malaria parasites.</p

On the extraction of cellulose nanowhiskers from food by-products and their comparative reinforcing effect on a polyhydroxybutyrate-co-valerate polymer

The present work reports on the characterization of cellulose nanowhiskers (CNW) extracted from three different food by-products, i.e., wheat straw (WSCNW), Brewers spent grains (BGCNW) and olive pomace (OPCNW), by using an optimized hydrolysis method similar to that developed to extract bacterial cellulose nanowhiskers (BCNW). WSCNW and BGCNW were seen to present optimal properties, with aspect ratio, crystallinity and thermal stability values comparable to those of BCNW. Additionally, the optimized hydrolysis treatment led to extraction yields higher than those previously reported for food by-products. The CNW were subsequently incorporated into a commercial polyhydroxybutyrate-co-valerate polymer (PHBV) by solution casting, and the produced nanocomposites were characterized. Although the addition of BGCNW and WSCNW was advantageous in terms of mechanical performance in comparison with OPCNW, no significant enhancement of the pure PHBV mechanical properties was reported because of the low nanofiller loadings used and the inherent difficulty of achieving a high degree of dispersion by the casting method. Interestingly, BGCNW and WSCNW presented reduced moisture sensitivity as compared with BCNW, leading to greater barrier performance and resulting in oxygen permeability reductions up to 26 % with WSCNW and 44 % with BGCNW.Noelle Peutat, on leave from the University of Grenoble in France, is acknowledged for her great dedication and support in the experimental work. M. Martinez-Sanz would like to thank the Spanish Ministry of Education for FPU Grant 1484. The authors acknowledge financial support from the EU FP7 ECOBIOCAP Project. The Electronic Microscopy Department in the SCIE from the University of Valencia is acknowledged for the support with SEM and TEM analyses. The Portuguese authors also acknowledge support from the FCT (Portuguese Foundation for Science and Technology) through strategic project PEst-OE/EQB/LA0023/2013

Analysis of construction accidents in Spain, 2003-2008

The research objective for this paper is to obtain a new extended and updated insight to the likely causes of construction accidents in Spain, in order to identify suitable mitigating actions. Method: The paper analyzes all construction sector accidents in Spain between 2003 and 2008. Ten variables were chosen and the influence of each variable is evaluated with respect to the severity of the accident. The descriptive analysis is based on a total of 1,163,178 accidents. Results: Results showed that the severity of accidents was related to variables including age, CNAE (National Classification of Economic Activities) code, size of company, length of service, location of accident, day of the week, days of absence, deviation, injury, and climatic zones. Conclusions: According to data analyzed, a large company is not always necessarily safer than a small company in the aspect of fatal accidents, experienced workers do not have the best accident fatality rates, and accidents occurring away from the usual workplace had more severe consequences. Impact on the industry: Results obtained in this paper can be used by companies in their occupational safety strategies, and in their safety training programs

Testing Categorical Moderators in Mixed-Effects Meta-analysis in the Presence of Heteroscedasticity

Mixed-effects models can be used to examine the association between a categorical moderator and the magnitude of the effect size. Two approaches are available to estimate the residual between-studies variance, τ2res—namely, separate estimation within each category of the moderator versus pooled estimation across all categories. We examine, by means of a Monte Carlo simulation study, both approaches for τ2res estimation in combination with two methods, the Wald-type χ2 and F tests, to test the statistical significance of the moderator. Results suggest that the F test using a pooled estimate of τ2res across categories is the best option in most conditions, although the F test using separate estimates of τ2res is preferable if the residual heterogeneity variances are heteroscedastic

Molecular rearrangement of starch during enzyme digestion as inferred by scattering techniques.

Resistant starch (RS) is defined as the fraction of starch that escapes digestion in the small intestine, serving as a fermentation substrate for the beneficial colonic bacteria. Understanding the structure that makes these fractions resistant to digestion is of outstanding importance as it assists in the design of food products with increasing RS content. Several studies have been focussed on the description of the RS fractions from several starch varieties, but little attention has been paid to the digestion process itself, which from the present work, seems to play a key role in the understanding of what is RS.RACI Cereal Chemistry Divisio

Safety risk assessment for vertical concrete formwork activities in civil engineering construction

BACKGROUND: The construction sector has one of the worst occupational health and safety records in Europe. Of all construction tasks, formwork activities are associated with a high frequency of accidents and injuries. OBJECTIVE: This paper presents an investigation of the activities and related safety risks present in vertical formwork for in-situ concrete construction in the civil engineering sector. METHODS: Using the methodology of staticized groups, twelve activities and ten safety risks were identified and validated by experts. Every safety risk identified in this manner was quantified for each activity using binary methodology according to the frequency and severity scales developed in prior research. A panel of experts was selected according to the relevant literature on staticized groups. RESULTS: The results obtained show that the activities with the highest risk in vertical formwork tasks are: Plumbing and leveling of forms, cutting of material, handling materials with cranes, and climbing or descending ladders. The most dangerous health and safety risks detected were falls from height, cutting and overexertion. CONCLUSIONS: The research findings provide construction practitioners with further evidence of the hazardous activities associated with concrete formwork construction and a starting point for targeting worker health and safety programmes

Dust emission at 8-mic and 24-mic as Diagnostics of HII Region Radiative Transfer

We use the Spitzer SAGE survey of the Magellanic Clouds to evaluate the relationship between the 8-mic PAH emission, 24-mic hot dust emission, and HII region radiative transfer. We confirm that in the higher-metallicity Large Magellanic Cloud, PAH destruction is sensitive to optically thin conditions in the nebular Lyman continuum: objects identified as optically thin candidates based on nebular ionization structure show 6 times lower median 8-mic surface brightness (0.18 mJy arcsec^-2) than their optically thick counterparts (1.2 mJy arcsec^-2). The 24-mic surface brightness also shows a factor of 3 offset between the two classes of objects (0.13 vs 0.44 mJy arcsec^-2, respectively), which is driven by the association between the very small dust grains and higher density gas found at higher nebular optical depths. In contrast, PAH and dust formation in the low-metallicity Small Magellanic Cloud is strongly inhibited such that we find no variation in either 8-mic or 24-mic emission between our optically thick and thin samples. This is attributable to extremely low PAH and dust production together with high, corrosive UV photon fluxes in this low-metallicity environment. The dust mass surface densities and gas-to-dust ratios determined from dust maps using Herschel HERITAGE survey data support this interpretation.Comment: Accepted to ApJ, May 15, 2017. 10 pages, 9 figure

Guidelines for Reporting Systematic Reviews and Meta-analyses

Meta-analysis is an essential methodology that allows researchers to synthesize the scientific evidence available on a given research question. Due to its wide applicability in most applied research fields, it is really important that meta-analyses be written and reported appropriately. In this paper we propose some guidelines to report the results of a meta-analysis in a scientific journal as Annals of Psychology. Concretely, the structure for reporting a meta-analysis following its different stages is detailed. In addition, some recommendations related to the usual tasks when conducting a meta-analysis are provided. A recent meta-analysis focused on the psychological field is used to illustrate the guidelines proposed. Finally, some concluding remarks are presented. El meta-análisis es una metodología esencial que permite a los investigadores sintetizar la evidencia científica disponible sobre una determinada cuestión de investigación. Debido a su amplia aplicabilidad en la mayoría de los campos de investigación aplicados, es realmente importante que los meta-análisis se escriban y se reporten de manera apropiada. En este artículo proponemos pautas para reportar los resultados de un meta-análisis en una revista científica como Anales de Psicología. Concretamente, se detalla la estructura para reportar un meta-análisis siguiendo sus fases. Además, proporcionamos recomendaciones relacionadas con las tareas usuales en meta-análisis. Un meta-análisis reciente centrado en el campo de la psicología es usado para ilustrar las guías propuestas. Finalmente, presentamos algunas observaciones finales