Recurrent Modification of a Conserved Cis-Regulatory Element Underlies Fruit Fly Pigmentation Diversity

The development of morphological traits occurs through the collective action of networks of genes connected at the level of gene expression. As any node in a network may be a target of evolutionary change, the recurrent targeting of the same node would indicate that the path of evolution is biased for the relevant trait and network. Although examples of parallel evolution have implicated recurrent modification of the same gene and cis-regulatory element (CRE), little is known about the mutational and molecular paths of parallel CRE evolution. In Drosophila melanogaster fruit flies, the Bric-à-brac (Bab) transcription factors control the development of a suite of sexually dimorphic traits on the posterior abdomen. Female-specific Bab expression is regulated by the dimorphic element, a CRE that possesses direct inputs from body plan (ABD-B) and sex-determination (DSX) transcription factors. Here, we find that the recurrent evolutionary modification of this CRE underlies both intraspecific and interspecific variation in female pigmentation in the melanogaster species group. By reconstructing the sequence and regulatory activity of the ancestral Drosophila melanogaster dimorphic element, we demonstrate that a handful of mutations were sufficient to create independent CRE alleles with differing activities. Moreover, intraspecific and interspecific dimorphic element evolution proceeded with little to no alterations to the known body plan and sex-determination regulatory linkages. Collectively, our findings represent an example where the paths of evolution appear biased to a specific CRE, and drastic changes in function were accompanied by deep conservation of key regulatory linkages. © 2013 Rogers et al

Optimization viewpoint on Kalman smoothing, with applications to robust and sparse estimation

In this paper, we present the optimization formulation of the Kalman filtering and smoothing problems, and use this perspective to develop a variety of extensions and applications. We first formulate classic Kalman smoothing as a least squares problem, highlight special structure, and show that the classic filtering and smoothing algorithms are equivalent to a particular algorithm for solving this problem. Once this equivalence is established, we present extensions of Kalman smoothing to systems with nonlinear process and measurement models, systems with linear and nonlinear inequality constraints, systems with outliers in the measurements or sudden changes in the state, and systems where the sparsity of the state sequence must be accounted for. All extensions preserve the computational efficiency of the classic algorithms, and most of the extensions are illustrated with numerical examples, which are part of an open source Kalman smoothing Matlab/Octave package.Comment: 46 pages, 11 figure

Combined sedation with midazolam/propofol for gastrointestinal endoscopy in elderly patients

<p>Abstract</p> <p>Background</p> <p>Although gastrointestinal endoscopy with sedation is increasingly performed in elderly patients, data on combined sedation with midazolam/propofol are very limited for this age group.</p> <p>Methods</p> <p>We retrospectively analyzed 454 endoscopic procedures in 347 hospitalized patients ≥ 70 years who had received combined sedation with midazolam/propofol. 513 endoscopic procedures in 397 hospitalized patients < 70 years during the observation period served as controls. Characteristics of endoscopic procedures, co-morbidity, complications and mortality were compared.</p> <p>Results</p> <p>Elderly patients had a higher level of co-morbidity and needed lower mean propofol doses for sedation. We observed no major complication and no difference in the number of minor complications. The procedure-associated mortality was 0%; the 28-day mortality was significantly higher in the elderly (2.9% vs. 1.0%).</p> <p>Conclusions</p> <p>In this study on elderly patients with high level co-morbidity, a favourable safety profile was observed for a combined sedation with midazolam/propofol with a higher sensitivity to propofol in the elderly.</p

Pralidoxime in Acute Organophosphorus Insecticide Poisoning-A Randomised Controlled Trial

Background: Poisoning with organophosphorus (OP) insecticides is a major global public health problem, causing an estimated 200,000 deaths each year. Although the World Health Organization recommends use of pralidoxime, this antidote's effectiveness remains unclear. We aimed to determine whether the addition of pralidoxime chloride to atropine and supportive care offers benefit. Methods and Findings: We performed a double-blind randomised placebo-controlled trial of pralidoxime chloride (2 g loading dose over 20 min, followed by a constant infusion of 0.5 g/h for up to 7 d) versus saline in patients with organophosphorus insecticide self-poisoning. Mortality was the primary outcome; secondary outcomes included intubation, duration of intubation, and time to death. We measured baseline markers of exposure and pharmacodynamic markers of response to aid interpretation of clinical outcomes. Two hundred thirty-five patients were randomised to receive pralidoxime (121) or saline placebo (114). Pralidoxime produced substantial and moderate red cell acetylcholinesterase reactivation in patients poisoned by diethyl and dimethyl compounds, respectively. Mortality was nonsignificantly higher in patients receiving pralidoxime: 30/121 (24.8%) receiving pralidoxime died, compared with 18/114 (15.8%) receiving placebo (adjusted hazard ratio HR] 1.69, 95% confidence interval CI] 0.88-3.26, p = 0.12). Incorporating the baseline amount of acetylcholinesterase already aged and plasma OP concentration into the analysis increased the HR for patients receiving pralidoxime compared to placebo, further decreasing the likelihood that pralidoxime is beneficial. The need for intubation was similar in both groups (pralidoxime 26/121 21.5%], placebo 24/114 21.1%], adjusted HR 1.27 95% CI 0.71-2.29]). To reduce confounding due to ingestion of different insecticides, we further analysed patients with confirmed chlorpyrifos or dimethoate poisoning alone, finding no evidence of benefit. Conclusions: Despite clear reactivation of red cell acetylcholinesterase in diethyl organophosphorus pesticide poisoned patients, we found no evidence that this regimen improves survival or reduces need for intubation in patients with organophosphorus insecticide poisoning. The reason for this failure to benefit patients was not apparent. Further studies of different dose regimens or different oximes are required

Ca2+ monitoring in Plasmodium falciparum using the yellow cameleon-Nano biosensor

Calcium (Ca2+)-mediated signaling is a conserved mechanism in eukaryotes, including the human malaria parasite, Plasmodium falciparum. Due to its small size (300?nM). We determined that the mammalian SERCA inhibitor thapsigargin and antimalarial dihydroartemisinin did not perturb SERCA activity. The change of the cytosolic Ca2+ level in P. falciparum was additionally detectable by flow cytometry. Thus, we propose that the developed YC-Nano-based system is useful to study Ca2+ signaling in P. falciparum and is applicable for drug screening.We are grateful to Japanese Red Cross Blood Society for providing human RBC and plasma. We also thank Tanaka R, Ogoshi (Sakura) M and Matsumoto N for technical assistance and Templeton TJ for critical reading. This study was conducted at the Joint Usage / Research Center on Tropical Disease, Institute of Tropical Medicine, Nagasaki University, Japan. KP was a Tokyo Biochemical Research Foundation (TBRF, http://www.tokyobrf.or.jp) post-doctoral fellow and PEF was a Japanese Society of Promotion Sciences (JSPS) post-doctoral fellow. This work was supported in part by the TBRF (K.P.), JSPS (P.E.F.), Takeda Science Foundation (K.Y.), Grants-in-Aids for Scientific Research 24590509 (K.Y.), 22390079 (O.K.), and for Scientific Research on Innovative Areas 23117008 (O.K.), MEXT, Japan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Sepsid even-skipped enhancers are functionally conserved in Drosophila despite lack of sequence conservation

10.1371/journal.pgen.1000106PLoS Genetics46

Hypopituitarism is associated with lower oxytocin concentrations and reduced empathic ability

Purpose Central diabetes insipidus is characterised by arginine vasopressin deficiency. Oxytocin is structurally related to vasopressin and is synthesised in the same hypothalamic nuclei, thus we hypothesised that patients with acquired central diabetes insipidus and anterior hypopituitarism would display an oxytocin deficiency. Moreover, psychological research has demonstrated that oxytocin influences social and emotional behaviours, particularly empathic behaviour. We therefore further hypothesised that central diabetes insipidus patients would perform worse on empathy-related tasks, compared to age-matched and gender-matched clinical control (clinical control-isolated anterior hypopituitarism) and healthy control groups. Method Fifty-six participants (age 46.54 ± 16.30 yrs; central diabetes insipidus: n = 20, 8 males; clinical control: n = 15, 6 males; healthy control: n = 20, 7 males) provided two saliva samples which were analysed for oxytocin and completed two empathy tasks. Results Hypopituitary patients (both central diabetes insipidus and clinical control groups) had significantly lower oxytocin concentrations compared to healthy control participants. Hypopituitary patients also performed significantly worse on both the reading the mind in the eyes task and the facial expression recognition task compared to healthy control participants. Regression analyses further revealed that central diabetes insipidus patients’ oxytocin concentrations significantly predicted their performance on easy items of the reading the mind in the eyes task. Conclusions Hypopituitarism may therefore be associated with reduced oxytocin concentrations and impaired empathic ability. While further studies are needed to replicate these findings, our data suggest that oxytocin replacement may offer a therapeutic approach to improve psychological well-being in patients with hypopituitarism