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Rhodococcus erythropolis bacterium is known for its remarkable resistance characteristics that can be useful in several biotechnological processes, such as bioremediation. However, there is scarce knowledge concerning the behavior of this strain against different metals. This study sought to investigate the behavior of R. erythropolis ATCC 4277 against the residue of chalcopyrite and e-waste to verify both resistive capacities to the metals present in these residues and their potential use for biomining processes. These tests were carried out in a stirred tank bioreactor for 48 h, at 24ºC, pH 7.0, using a total volume of 2.0 L containing 2.5% (v/v) of a bacterial pre-culture. The pulp density of chalcopyrite was 5% (w/w), and agitation and oxygen flow rates were set to 250 rpm and 1.5 LO2 min−1, respectively. On the other hand, we utilized a waste of computer printed circuit board (WPCB) with a pulp density of 10% (w/w), agitation at 400 rpm, and an oxygen flow rate of 3.0 LO2 min−1. Metal concentration analyses post-fermentation showed that R. erythropolis ATCC 4277 was able to leach about 38% of the Cu present in the chalcopyrite residue (in ~ 24 h), and 49.5% of Fe, 42.3% of Ni, 27.4% of Al, and 15% Cu present in WPCB (in ~ 24 h). In addition, the strain survived well in the environment containing such metals, demonstrating the potential of using this bacterium for waste biomining processes as well as in other processes with these metals. [ABSTRACT FROM AUTHOR]

Pyridoxal 5'-phosphate (PLP)-dependent enzymes utilize a vitamin B6-derived cofactor to perform a myriad of chemical transformations on amino acids and other small molecules. Some PLP-dependent enzymes, such as serine hydroxymethyltransferase (SHMT), are promising drug targets for the design of small-molecule antimicrobials and anticancer therapeutics, while others have been used to synthesize pharmaceutical building blocks. Understanding PLP-dependent catalysis and the reaction specificity is crucial to advance structure-assisted drug design and enzyme engineering. Here we report the direct determination of the protonation states in the active site of Thermus thermophilus SHMT (TthSHMT) in the internal aldimine state using room-temperature joint X-ray/neutron crystallography. Conserved active site architecture of the model enzyme TthSHMT and of human mitochondrial SHMT (hSHMT2) were compared by obtaining a room-temperature X-ray structure of hSHMT2, suggesting identical protonation states in the human enzyme. The amino acid substrate serine pathway through the TthSHMT active site cavity was tracked, revealing the peripheral and cationic binding sites that correspond to the pre-Michaelis and pseudo-Michaelis complexes, respectively. At the peripheral binding site, the substrate is bound in the zwitterionic form. By analyzing the observed protonation states, Glu53, but not His residues, is proposed as the general base catalyst, orchestrating the retro-aldol transformation of L-serine into glycine. Serine hydroxymethyltransferase (SHMT) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme and a promising drug target, however, PLP-dependent catalysis remains underexplored. Here, the authors report joint X-ray/neutron structures of Thermus thermophilus SHMT in the internal aldimine state and in complex with L-serine substrate trapped at the peripheral binding site, revealing positions of hydrogen atoms, assigning the protonation states and electrical charges of residues, and proposing a catalytic mechanism. [ABSTRACT FROM AUTHOR]

Due to its relationship with oxidative stress and inflammation responses, obesity and its cardiometabolic implications have been related with serum copper (Cu). Hence, we analyzed the association of overweight (OW) and obesity (OB) status and cardiometabolic traits with serum Cu level in Mexican schoolchildren. Anthropometrical data and cardiometabolic traits were analyzed in this cross-sectional study. Serum Cu level was measured by inductively coupled plasma mass spectrometry. The study involved 191 schoolchildren (93 girls and 98 boys) with a mean age of 8.054 ± 1.170 years. Children with OW and OB had higher serum Cu levels than children with normal weight (NW) (mean difference: OW vs NW = 51.85 µg dL−1, OB vs NW = 47.22 µg dL−1, p < 0.001). In a multiple linear regression model, OW and OB status were positively associated with serum Cu levels (βOW = 49.85, 95% confidence interval (95% CI) 35.84–63.87, p < 0.001; βOB = 44.38, 95% CI 27.70–61.05, p < 0.001). We did not identify any significant association between cardiometabolic traits and serum Cu level. In conclusion, our results show an association of the presence of OW and OB with higher serum Cu levels, for the first time in Mexican schoolchildren. However, further functional studies are needed to better understand the role of Cu in the pathophysiology of obesity. [ABSTRACT FROM AUTHOR]

Previous researchers have demonstrated that using stimuli identified via daily brief preference assessments may produce more responding under concurrent-schedule arrangements than using stimuli identified via lengthy, pre-treatment preference assessments (DeLeon et al., 2001). To date, this has not been evaluated within the context of skill acquisition. Thus, the extent to which conducting daily brief preference assessments impacts the rate of skill acquisition during discrete trial instruction (DTI) remains unknown. The purpose of this study was to evaluate how frequent, pre-session preference assessments, influence the rate of skill acquisition relative to an initial preference assessment during DTI sessions for three children with autism spectrum disorder (ASD). Two of the three children acquired the targeted skills faster in the frequent preference assessment condition. The third participant showed no difference in the rate of skill acquisition. [ABSTRACT FROM AUTHOR]

Background: The ecological indicators are useful tools to determine the effects of human disturbances on woodland biodiversity. Nevertheless, ecological indicators not always responded in the same way to disturbances, and the responses can differ among taxa. In arid and semiarid woodlands, the use of deadwood associated with cattle raising can affect biodiversity and Nature's contributions to people. Methods: Our study aimed to assess changes in taxonomic and functional diversity of two assemblages, plants and mammals, in Prosopis woodlands under different land management types: grazed woodlands and a protected area. For plants, changes in structural diversity were also analyzed. Prosopis trees under different land management types were selected and their deadwood characteristics were registered. Through live traps and camera traps, we obtained data on the presence-absence of mammals per tree to estimate diversity indices. For plants, we measured the abundance of vegetation by species and by cover type through the Line-Intercept Method to estimated diversity. Finally, we built generalized linear models to assess the responses of diversity of each assemblage to covariables concerning deadwood and different land management types. Results: We found that all diversity indeces for plants were either negatively affected by the presence of deadwood on the ground, or favored by its extraction. For mammals, removal of deadwood increased taxonomic diversity, while functional diversity increased with deadwood on the trees. Both structural diversity of plants and functional diversity of mammals were greater in grazed woodlands. Conclusions: The sustainable use of woodland resources is essential for the activities of rural communities. Our study results indicated that land management of grazed woodlands promoted the structural diversity of plant assemblages and the functional diversity of mammals. The presence of deadwood negatively affected plant diversity but it increased mammal functional diversity. It is advisable to maintain trees that preserve their wooden structure within the managed areas to promote the functional diversity of mammals, while trees with extraction from standing wood will favor the functional diversity of the plant assemblage. Understanding the effects of human disturbances can contribute to management for the conservation of woodlands diversity and Nature's contributions to people. [ABSTRACT FROM AUTHOR]

All cellular processes can be ultimately understood in terms of respective fundamental biochemical interactions between molecules, which can be modeled as networks. Very often, these molecules are shared by more than one process, therefore interconnecting them. Despite this effect, cellular processes are usually described by separate networks with heterogeneous levels of detail, such as metabolic, protein–protein interaction, and transcription regulation networks. Aiming at obtaining a unified representation of cellular processes, we describe in this work an integrative framework that draws concepts from rule-based modeling. In order to probe the capabilities of the framework, we used an organism-specific database and genomic information to model the whole-cell biochemical network of the Mycoplasma genitalium organism. This modeling accounted for 15 cellular processes and resulted in a single component network, indicating that all processes are somehow interconnected. The topological analysis of the network showed structural consistency with biological networks in the literature. In order to validate the network, we estimated gene essentiality by simulating gene deletions and compared the results with experimental data available in the literature. We could classify 212 genes as essential, being 95% of them consistent with experimental results. Although we adopted a relatively simple organism as a case study, we suggest that the presented framework has the potential for paving the way to more integrated studies of whole organisms leading to a systemic analysis of cells on a broader scale. The modeling of other organisms using this framework could provide useful large-scale models for different fields of research such as bioengineering, network biology, and synthetic biology, and also provide novel tools for medical and industrial applications. [ABSTRACT FROM AUTHOR]

Much attention has been focused on investigating the effects of climate change on hydrological processes on a regional scale. However, the landscape approach, especially the case of well-preserved upland watersheds needs to be further studied. The Representative Concentration Pathway (RCP) or emission scenarios RCP 4.5 and RCP 8.5 were used to project the impacts of the climate change on the hydrological components of a well-preserved upland landscape with temperate climate, using the Upper Canoas watershed as a case study. The future hydrological projection indicated an increase in the monthly rainfall as well as a shift in the rainiest months from winter to spring. This change resulted in an increase in water balance components. The maximum discharges, as well as the modal discharge (Q50), may increase in the future, and the minimums corresponding to Q95 and Q98 may reduce for both emission scenarios. The results showed that a well-preserved upland watershed in a sub-tropical region might be capable of maintaining water availability at level that is enough for human activities in the future, even with the reduction of minimum permit discharge, which is supported by the increase of maximum and medium monthly discharges and a stable flow-duration curve. [ABSTRACT FROM AUTHOR]

Disparities for genetic cancer risk assessment (GCRA) for hereditary breast and ovarian cancer (HBOC) persist between Latina and non-Hispanic Whites. There are few tested culturally targeted interventions. We developed a culturally targeted video to enhance GCRA uptake in at-risk Latinas. Interviews with healthcare providers (n = 20) and at-risk Latinas (n = 20) were conducted as formative research to inform the development of the video. Findings from the formative research, health behavior conceptual models, and evidence-based risk communication strategies informed the messages for the script. Then, we conducted a focus group with at-risk Latinas (n = 7) to obtain feedback for final refinement of the script. The final video was piloted for acceptability and potential dissemination in a sample of Latino community health workers (CHWs) (n = 31). Providers and at-risk Latinas suggested using simple language and visual aids to facilitate comprehension. Participants in the focus group identified areas for further clarification (e.g., cost). The result was an 18-min video that illustrates "Rosa's" story. Rosa learns about HBOC risk factors and overcomes barriers to attend genetic counseling. CHWs reported high overall satisfaction with the video (M = 9.61, SD =.88, range 1–10). A culturally targeted video has the potential to reach underserved populations with low literacy and English proficiency. [ABSTRACT FROM AUTHOR]

Background: Hypertensive urgency (HU), defined as acute severe uncontrolled hypertension without end-organ damage, is a common condition. Despite its association with long-term morbidity and mortality, guidance regarding immediate management is sparse. Our objective was to summarize the evidence examining the effects of antihypertensive medications to treat.Methods: We searched the PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Reviews of Effects (DARE), Cochrane Database of Systematic Reviews, Web of Science, Google Scholar, and Embase through May 2016.Study Selection: We evaluated prospective controlled clinical trials, case-control studies, and cohort studies of HU in emergency room (ER) or clinic settings. We initially identified 11,223 published articles. We reviewed 10,748 titles and abstracts and identified 538 eligible articles. We assessed the full text for eligibility and included 31 articles written in English that were clinical trials or cohort studies and provided blood pressure data within 48 h of treatment. Studies were appraised for risk of bias using components recommended by the Cochrane Collaboration. The main outcome measured was blood pressure change with antihypertensive medications. Since studies were too diverse both clinically and methodologically to combine in a meta-analysis, tabular data and a narrative synthesis of studies are presented.Results: We identified only 20 double-blind randomized controlled trials and 12 cohort studies, with 262 participants in prospective controlled trials. However, we could not pool the results of studies. In addition, comorbidities and their potential contribution to long-term treatment of these subjects were not adequately addressed in any of the reviewed studies.Conclusions: Longitudinal studies are still needed to determine how best to lower blood pressure in patients with HU. Longer-term management of individuals who have experienced HU continues to be an area requiring further study, especially as applicable to care from the generalist. [ABSTRACT FROM AUTHOR]

Asymmetric division of neural precursor cells contributes to the generation of a variety of neuronal types. Asymmetric division is mediated by the asymmetric inheritance of fate determinants by the two daughter cells. In vertebrates, asymmetric fate determinants, such as Par3 and Mib, are only now starting to be identified. Here we show that, during mitosis of neural precursors in zebrafish, directional trafficking of Sara endosomes to one of the daughters can function as such a determinant. In asymmetric lineages, where one daughter cell becomes a neuron (n cell) whereas the other divides again to give rise to two neurons (p cell), we found that the daughter that inherits most of the Sara endosomes acquires the p fate. Sara endosomes carry an endocytosed pool of the Notch ligand DeltaD, which is thereby itself distributed asymmetrically. Sara and Notch are both essential for cell fate assignation within asymmetric lineages. Therefore, the Sara endosome system determines the fate decision between neuronal differentiation and mitosis in asymmetric lineages and thereby contributes to controlling the number of neural precursors and differentiated neurons during neurogenesis in a vertebrate. [ABSTRACT FROM AUTHOR]

This study reports the cloning, expression analysis and localization of calreticulin (CRT) in the endoplasmic reticulum (ER) during late oogenesis and early embryogenesis of the insect Rhodnius prolixus. CRT was cloned and sequenced from cDNA extracted from unfertilized eggs. Real-time PCR showed that CRT expression remains at lower levels during late oogenesis when compared to vitellogenic oocytes or day 0 laid fertilized eggs. Immunofluorescence microscopy showed that this protein is located in the periphery of the egg, in a differential peripheral ooplasm surrounding the yolk-rich internal ooplasm, only identified by transmission electron microscopy (TEM) of thin sections. Using immunogold electron microscopy, the ER ultrastructure (CRT labeled) was identified in the peripheral ooplasm as dispersed lamellae, randomly distributed in the peripheral ooplasm. No massive alterations of ER ultrastructure were found before or right after (30 min) fertilization, but an increase in CRT expression levels and assembly of typical rough ER (parallel cisternae with associated ribosomes) were observed 18-24 h after oviposition. The lack of ER assembly at fertilization and the later formation of rough ER together with the increase in CRT expression levels, suggest that the major functions of ER might be of great importance during the early events of development. The possible involvement of ER in the early steps of embryogenesis will be discussed. [ABSTRACT FROM AUTHOR]

Great differences in crystallographic phases, magnetic properties, and catalytic activity were detected in lanthanum cobaltite and cobaltite modified with the insertion of 10 wt.% of Mn. Atomic absorption spectroscopy, BET area measurements, XRD analysis, TPR, and FT-IR suggest that the total insertion of manganese in the LaCoO3 structure is successful. Thermal stability is reached for LaCo0.90Mn0.10O3 up to 973 K without loss of the perovskite structure. The magnetic properties of the as-grown compounds are maintained after a first reduction process up to 723–773 K, while presence of segregated phases is observed after reduction at 973 K. The catalytic activity evaluated in the total combustion of acetyl acetate shows a decrease in the ignition temperature, i.e. an increase in the catalytic activity for the LaCo0.90Mn0.10O3 perovskite. A significant enhancement in the catalytic activity expressed as intrinsic activity, mol m−2 h−1, with the manganese substitution was found. [ABSTRACT FROM AUTHOR]

Fecal bacteria have been used for more than a century as indicators of fecal contamination in water. In recent years, the monitoring of somatic and F-specific coliphages has been gradually included in guidelines and regulations as an additional parameter to reinforce water safety. The Escherichia coli host strain CB390 was tailored to detect both somatic and F-specific coliphages in a single test. The efficacy of this strain for bacteriophage detection, previously evaluated in Western Europe and North America, was assessed here for the first time in South America. The detection of somatic and F-specific coliphages by the strain CB390, as well as by standardized methods, was performed in drinking and river water and municipal and abattoir wastewaters. No statistical difference was found in the numbers of total coliphages detected by strain CB390 and the sum of somatic and F-specific coliphages determined separately by the standardized ISO methods. The data presented here provide further validation of the effectiveness of the host strain E. coli CB390 for the detection of total coliphages in waters in a single test and demonstrate its suitability for application in upper-middle income countries of the Americas (World Bank category). [ABSTRACT FROM AUTHOR]

The original version of this Article contained an error in the Acknowledgements, which incorrectly omitted the following: 'C.C., C.A., and J.C.H. were supported by the Fundação Calouste Gulbenkian through a grant from the Instituto Gulbenkian de Ciência and by the research infrastructure Congento, project LISBOA-01-0145-FEDER-022170, co-financed by Lisboa Regional Operational Programme (Lisboa 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and Foundation for Science and Technology (Portugal).' This has been corrected in both the PDF and HTML versions of the Article. [ABSTRACT FROM AUTHOR]