Characterization of esterase activity from the bacteria, Francisella tularensis, the causative agent of tularemia

Francisella tularensis is the bacteria responsible for causing the disease tularemia and is listed as one of the top three-biowarfare agents. Among the proteins essential to the virulence and infectivity of F.tularensis are multiple esterases, which are enzymes that break down various ester, thioester, and amide bonds. In this project, the catalytic activity, substrate speci fi city, and structure of a putative esterase from F.tularensis was studied. Latent fluorophores based on the molecule, fluorescein, were unmasked by the enzymatic activity of the esterase and the increase in fluorescence was measured over time to determine how well the e tcrase recognized different substrates. The esterase FlT258 from F. IIJlarensis activated a variety of simple latent fluorophore substrates with catalytic efficiencies ranging from 5075 M s for a simple propyl ester to 294.8 M\u27 \u27s for a teniary e ter. These simple substrates were recognized by the esterase with KM va lues ranging from 0.54 to 2 1.4 f,M , and sterically occluded substrates had significantly reduced kinetic turnover (kc ,) compared to the simplest substrates. In addition to the wild type esterase, the kinetic a tivity of five different variants of the esterase with single amino acid mutations were characterized against two latent fluorophore substrates to determine more information about the binding pocket of the esterase. The kinetic activity of each of the variants decreased significantly from the wild-type enzyme activity and indicated that the binding pocket is fairly invariant to substitution. Activity, 3D structure, and primary structure comparisons suggest that this esterase belongs to the carboxylesterasc family. Although lillie is known about the specific biological role of FTI 0258C and other carboxylesterases from its fanlily, the promiscuity of its enzymatic eclJ\ll) ould Ix uoollO dc\ I P f\u27OlmlJ:tl Jru m,\u3edcl thaI ulIlll 1M Un

An investigation of techniques that aim to improve the quality of labels provided by the crowd

The 2013 MediaEval Crowdsourcing task looked at the problem of working with noisy crowdsourced annotations of image data. The aim of the task was to investigate possible techniques for estimating the true labels of an image by using the set of noisy crowdsourced labels, and possibly any content and metadata from the image itself. For the runs in this paper, we’ve applied a shotgun approach and tried a number of existing techniques, which include generative probabilistic models and further crowdsourcing

Changes and good intentions

Programma di indirizzo della rivista AIB Studi, della quale gli autori hanno assunto la direzione scientific

Stabilising urea nitrogen enhances flowering, nitrogen use efficiency, and growth habit for stress tolerance in ornamental plants

Purpose: Supplying plants with nitrogen in ammonium nitrate- or urea-based fertiliser is wasteful: much is degraded before acquisition, releasing environmental pollutants. Preventing urea degradation can reduce pollution and improve crop nitrogen use efficiency. We investigate benefits to ureic stabilisation, on flowering and stress tolerance, as organic nitrogen sources favourably alter biomass partitioning in this regard. Research Method: We test effects of adding chemically stabilised urea to soil, on the physical form and flowering of containerised, greenhouse-grown pelargonium, petunia, pansy and marigold, when transplanting seedlings to larger pots. Efficacies of stabilised urea, non-stabilised urea and industry standard fertiliser are compared under identical total nitrogen supply. The significance of treatment differences is calculated using a one-tailed t-test. Findings: Development is favourably altered by ureic stabilisation. Earliest changes measured are increased root lengths, leaf growth rates and chlorophyll concentrations. Plants then develop more shoots and 25-130% more flowers. Improvements arise partially through increased nitrogen longevity in soil, and partially through positive effects of urea itself on biomass partitioning between organs, and on plant physiology; giving rise to improved commercial attributes (more branches and flowers) and tolerance to stress (more root, less apical dominance, more chlorophyll). Research Limitations: Further research could measure leachate nitrogen content, and compare different methods of ureic stabilisation in more crops. Originality/Value: Urea stabilisation can increase fruit and flower yields, whilst reducing vulnerability to erratic climates, and fertiliser-derived pollution. We propose that urea’s effectiveness arises because plants have evolved strategies to proliferate whilst competing with micro-organisms for organic nitrogen

Treatment for epilepsy in pregnancy: neurodevelopmental outcomes in the child (Review).

Accumulating evidence suggests an association between prenatal exposure to antiepileptic drugs (AEDs) and increased risk of both physical anomalies and neurodevelopmental impairment. Neurodevelopmental impairment is characterised by either a specific deficit or a constellation of deficits across cognitive, motor and social skills and can be transient or continuous into adulthood. It is of paramount importance that these potential risks are identified, minimised and communicated clearly to women with epilepsy. Objectives To assess the effects of prenatal exposure to commonly prescribed AEDs on neurodevelopmental outcomes in the child and to assess the methodological quality of the evidence. Search methods We searched the Cochrane Epilepsy Group Specialized Register (May 2014), Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2014, Issue 4), MEDLINE (via Ovid) (1946 to May 2014), EMBASE (May 2014), Pharmline (May 2014) and Reprotox (May 2014). No language restrictions were imposed. Conference abstracts from the last five years were reviewed along with reference lists from the included studies. Selection criteria Prospective cohort controlled studies, cohort studies set within pregnancy registers and randomised controlled trials were selected for inclusion. Participants were women with epilepsy taking AED treatment; the two control groups were women without epilepsy and women with epilepsy who were not taking AEDs during pregnancy. Data collection and analysis Three authors (RB, JW and JG) independently selected studies for inclusion. Data extraction and risk of bias assessments were completed by five authors (RB, JW, AS, NA, AJM). The primary outcome was global cognitive functioning. Secondary outcomes included deficits in specific cognitive domains or prevalence of neurodevelopmental disorders. Due to substantial variation in study design and outcome reporting only limited data synthesis was possible. Main results Twenty‐two prospective cohort studies were included and six registry based studies. Study quality varied. More recent studies tended to be larger and to report individual AED outcomes from blinded assessments, which indicate improved methodological quality.The developmental quotient (DQ) was lower in children exposed to carbamazepine (CBZ) (n = 50) than in children born to women without epilepsy (n = 79); mean difference (MD) of ‐5.58 (95% confidence interval (CI) ‐10.83 to ‐0.34, P = 0.04). The DQ of children exposed to CBZ (n = 163) was also lower compared to children of women with untreated epilepsy (n = 58) (MD ‐7.22, 95% CI ‐12.76 to ‐ 1.67, P = 0.01). Further analysis using a random‐effects model indicated that these results were due to variability within the studies and that there was no significant association with CBZ. The intelligence quotient (IQ) of older children exposed to CBZ (n = 150) was not lower than that of children born to women without epilepsy (n = 552) (MD ‐0.03, 95% CI ‐3.08 to 3.01, P = 0.98). Similarly, children exposed to CBZ (n = 163) were not poorer in terms of IQ in comparison to the children of women with untreated epilepsy (n = 87) (MD 1.84, 95% CI ‐2.13 to 5.80, P = 0.36). The DQ in children exposed to sodium valproate (VPA) (n = 123) was lower than the DQ in children of women with untreated epilepsy (n = 58) (MD ‐8.72, 95% ‐14.31 to ‐3.14, P = 0.002). The IQ of children exposed to VPA (n = 76) was lower than for children born to women without epilepsy (n = 552) (MD ‐8.94, 95% CI ‐11.96 to ‐5.92, P < 0.00001). Children exposed to VPA (n = 89) also had lower IQ than children born to women with untreated epilepsy (n = 87) (MD ‐8.17, 95% CI ‐12.80 to ‐3.55, P = 0.0005). In terms of drug comparisons, in younger children there was no significant difference in the DQ of children exposed to CBZ (n = 210) versus VPA (n=160) (MD 4.16, 95% CI ‐0.21 to 8.54, P = 0.06). However, the IQ of children exposed to VPA (n = 112) was significantly lower than for those exposed to CBZ (n = 191) (MD 8.69, 95% CI 5.51 to 11.87, P < 0.00001). The IQ of children exposed to CBZ (n = 78) versus lamotrigine (LTG) (n = 84) was not significantly different (MD ‐1.62, 95% CI ‐5.44 to 2.21, P = 0.41). There was no significant difference in the DQ of children exposed to CBZ (n = 172) versus phenytoin (PHT) (n = 87) (MD 3.02, 95% CI ‐2.41 to 8.46, P = 0.28). The IQ abilities of children exposed to CBZ (n = 75) were not different from the abilities of children exposed to PHT (n = 45) (MD ‐3.30, 95% CI ‐7.91 to 1.30, P = 0.16). IQ was significantly lower for children exposed to VPA (n = 74) versus LTG (n = 84) (MD ‐10.80, 95% CI ‐14.42 to ‐7.17, P < 0.00001). DQ was higher in children exposed to PHT (n = 80) versus VPA (n = 108) (MD 7.04, 95% CI 0.44 to 13.65, P = 0.04). Similarly IQ was higher in children exposed to PHT (n = 45) versus VPA (n = 61) (MD 9.25, 95% CI 4.78 to 13.72, P < 0.0001). A dose effect for VPA was reported in six studies, with higher doses (800 to 1000 mg daily or above) associated with a poorer cognitive outcome in the child. We identified no convincing evidence of a dose effect for CBZ, PHT or LTG. Studies not included in the meta‐analysis were reported narratively, the majority of which supported the findings of the meta‐analyses. Authors' conclusions The most important finding is the reduction in IQ in the VPA exposed group, which are sufficient to affect education and occupational outcomes in later life. However, for some women VPA is the most effective drug at controlling seizures. Informed treatment decisions require detailed counselling about these risks at treatment initiation and at pre‐conceptual counselling. We have insufficient data about newer AEDs, some of which are commonly prescribed, and further research is required. Most women with epilepsy should continue their medication during pregnancy as uncontrolled seizures also carries a maternal risk

Thinking big and thinking small: A conceptual framework for best practices in community and stakeholder engagement in food, energy, and water systems

Community and stakeholder engagement is increasingly recognized as essential to science at the nexus of food, energy, and water systems (FEWS) to address complex issues surrounding food and energy production and water provision for society. Yet no comprehensive framework exists for supporting best practices in community and stakeholder engagement for FEWS. A review and meta‐synthesis were undertaken of a broad range of existing models, frameworks, and toolkits for community and stakeholder engagement. A framework is proposed that comprises situational awareness of the FEWS place or problem, creation of a suitable culture for engagement, focus on power‐sharing in the engagement process, co‐ownership, co‐generation of knowledge and outcomes, the technical process of integration, the monitoring processes of reflective and reflexive experiences, and formative evaluation. The framework is discussed as a scaffolding for supporting the development and application of best practices in community and stakeholder engagement in ways that are arguably essential for sound FEWS science and sustainable management

The impact of heart failure and chronic obstructive pulmonary disease on mortality in patients presenting with breathlessness

© 2018, The Author(s). Background: Differentiating heart failure from chronic obstructive pulmonary disease (COPD) in a patient presenting with breathlessness is difficult but may have implications for outcome. We investigated the prognostic impact of diagnoses of COPD and/or heart failure in consecutive patients presenting to a secondary care clinic with breathlessness. Methods: In patients with left ventricular systolic dysfunction (LVSD) by visual estimation, N-terminal pro B-type natriuretic peptide (NTproBNP) levels and spirometry were evaluated (N = 4986). Heart failure was defined as either LVSD worse than mild (heart failure with reduced ejection fraction) or LVSD mild or better and raised NTproBNP levels (> 400 ng/L) (heart failure with normal ejection fraction). COPD was defined as forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) ratio < 0.7. The primary outcome was all-cause mortality. Results: 1764 (35%) patients had heart failure alone, 585 (12%) had COPD alone, 1751 (35%) had heart failure and COPD, and 886 (18%) had neither. Compared to patients with neither diagnosis, those with COPD alone [hazard ratio (HR) = 1.84 95% confidence interval (CI) 1.40–2.43], heart failure alone [HR = 4.40 (95% CI 3.54–5.46)] or heart failure and COPD [HR = 5.44 (95% CI 4.39–6.75)] had a greater risk of death. COPD was not associated with increased risk of death in patients with heart failure on a multivariable analysis. Conclusion: While COPD is associated with increased risk of death compared to patients with neither heart failure nor COPD, it has a negligible impact on prognosis amongst patients with heart failure

Establishing haematological and biochemical reference intervals for free-ranging Scottish golden eagle nestlings (Aquila chrysaetos)

Health assessment of individuals is an important aspect of monitoring endangered wildlife populations. Haematological and biochemical values are a common health assessment tool, and whilst reference values are well established for domestic species, they are often not available for wild animal species. This study established 31 haematological and biochemical reference intervals for golden eagle (Aquila chrysaetos) nestlings in Scotland, in order to improve the understanding of the species’ health and support conservation efforts. Reference intervals were created from 47 nestlings (ages 2–7.5 weeks old) across 37 nests, to date, the largest sample of wild individuals of this species and age cohort sampled for these purposes. Upper reference intervals for concentrations of lymphocytes, total protein, cholesterol, triglycerides, uric acid, and monocytes, calculated in this study, are higher than those found for adult raptors and the interval span is higher than that observed in adult raptors for concentrations of AST, albumin, eosinophil, LDH, and monocyte count. Statistically significant positive correlations were found with age and concentrations of haemoglobin, lymphocytes, serum pH, and creatine kinase, and significant negative correlations with age for concentrations of thrombocytes, heterophils, total protein, globulin, and lactate dehydrogenase. Packed cell volume was significantly higher for females than males, and concentration of calcium and eosinophils were higher for individuals in good body condition than those in moderate body condition. The reference intervals produced by this study will be of important use to the veterinary and conservation management communities and will aid the long-term monitoring of the Scottish golden eagle population health