Medical Relief Trips...What’s Missing? Exploring Ethical Issues and the Physician-Patient Relationship

"The welcome ceremony alone will leave you breathless as you become inspired by their overwhelming joy at you arrival. Here you will participate with the community and provide much needed medical care. The team will also provide care for the Talibe boys in Theis who go without medical care and are left to face disease on their own (Senegal, 2009).

Speciation in Digital Organisms

Current estimates of the number of species on Earth range from four to forty million total species. Why are there so many species? The answer must include both ecology and evolution. Ecology looks at the interactions between coexisting species, while evolution tracks them through time. Both are required to understand aspects of environments which promote speciation, and which promote species persistence in time. The explanation for this biodiversity is still not well understood. I argue that resource limitations are a major factor in the evolutionary origin of complex ecosystems with interacting and persistent species. Through experiments with digital organisms in environment with multiple limited resources, I show that these conditions alone can be sufficient to induce differentiation in a population. Moreover, the observed pattern of species number distributions match patterns observed in nature. I develop a simple metric for phenotypic distance for digital organisms, which permits quantitative analysis of similarities within, and differences between species. This enables a clear species concept for digital organisms that may also be applied to biological organisms, thus helping to clarify the biological species concept. Finally, I will use this measurement methodology to predict species and ecosystem stability.</p

Drosophila Bruce Can Potently Suppress Rpr- and Grim-Dependent but Not Hid-Dependent Cell Death

Bruce is a large protein (530 kDa) that contains an N-terminal baculovirus IAP repeat (BIR) and a C-terminal ubiquitin conjugation domain (E2) 1, 2. BRUCE upregulation occurs in some cancers and contributes to the resistance of these cells to DNA-damaging chemotherapeutic drugs [2]. However, it is still unknown whether Bruce inhibits apoptosis directly or instead plays some other more indirect role in mediating chemoresistance, perhaps by promoting drug export, decreasing the efficacy of DNA damage-dependent cell death signaling, or by promoting DNA repair. Here, we demonstrate, using gain-of-function and deletion alleles, that Drosophila Bruce (dBruce) can potently inhibit cell death induced by the essential Drosophila cell death activators Reaper (Rpr) and Grim but not Head involution defective (Hid). The dBruce BIR domain is not sufficient for this activity, and the E2 domain is likely required. dBruce does not promote Rpr or Grim degradation directly, but its antiapoptotic actions do require that their N termini, required for interaction with DIAP1 BIR2, be intact. dBruce does not block the activity of the apical cell death caspase Dronc or the proapoptotic Bcl-2 family member Debcl/Drob-1/dBorg-1/Dbok. Together, these results argue that dBruce can regulate cell death at a novel point

A Review of Transcatheter Ablation for the Treatment of AVNRT in Children

Background: Atrioventricular nodal reentrant tachycardia (AVNRT) is an arrhythmia due to re-entrant rhythm within the region of the atrioventricular (AV) node, which accounts for most supraventricular tachycardia (SVT) cases in children. There are two main pathways involved for the re-entrant rhythm, slow and fast pathways, with different anatomic locations and involvement in the circuit associated with AVNRT. AVNRT is rare in newborns, but an increase of prevalence throughout childhood was previously reported.Study Objective/Purpose: Currently, Radiofrequency (RF) ablation is the primary method for the treatment of AVNRT in pediatrics. However, multiple modalities with varying efficacies can also be utilized. In this study, we attempt to review indications and complications of the gold-standard use of RF compared to newer modalities for the ablation treatment of AVNRT in the pediatric population. Results/Discussion: Currently there are two transcatheter ablations methods widely applied as AVNRT treatment: RF ablation and Cryoablation (Cryo). Indications for these methods vary with blood flow in the target area, duration of procedure, and risk of recurrence of AVNRT. Both methods have success rates \u3e90% in AVNRT children, with a 3% complication rate. AV block is the most common complication of RF ablation cases, while Cryo, being a newer technology, requires further investigation. Factors that complicate ablation in AVNRT include anatomical and electrophysiological variations between individuals. Fluoroscopic visualization and 3D-voltage mapping of pathways can provide markers for catheter ablation in AVNRT cases to expedite ablation success and enhance safety. Other predictors of success include: reduced fluoroscopy time, lower patient weight, the ability to induce junctional rhythm in the patient during the procedure, and the utilization of image-based guidance and ice-mapping during the ablation. Conclusion: Radiofrequency catheter ablation remains the highly successful gold standard for the treatment of AVNRT in children, with low complication rates. Cryoablation and other advanced techniques are emerging as new methods tailored to the accessory pathways and more sophisticated structural variations underlying AVNRT in children

Adaptive Radiation from Resource Competition in Digital Organisms

Species richness often peaks at intermediate productivity and decreases as resources become more or less abundant. The mechanisms that produce this pattern are not completely known, but several previous studies have suggested environmental heterogeneity as a cause. In experiments with evolving digital organisms and populations of fixed size, maximum species richness emerges at intermediate productivity, even in a spatially homogeneous environment, owing to frequency-dependent selection to exploit an influx of mixed resources. A diverse pool of limiting resources is sufficient to cause adaptive radiation, which is manifest by the origin and maintenance of phenotypically and phylogenetically distinct groups of organisms

Single-Cell Growth Rates in Photoautotrophic Populations Measured by Stable Isotope Probing and Resonance Raman Microspectrometry

A newmethod tomeasure growth rates of individual photoautotrophic cells by combining stable isotope probing (SIP) and single-cell resonance Raman microspectrometry is introduced. This report explores optimal experimental design and the theoretical underpinnings for quantitative responses of Raman spectra to cellular isotopic composition. Resonance Raman spectra of isogenic cultures of the cyanobacterium, Synechococcus sp., grown in 13C-bicarbonate revealed linear covariance between wavenumber (cm−1) shifts in dominant carotenoid Raman peaks and a broad range of cellular 13C fractional isotopic abundance. Single-cell growth rates were calculated from spectra-derived isotopic content and empirical relationships. Growth rates among any 25 cells in a sample varied considerably;mean coefficient of variation, CV, was 29±3%(s/x), of which only ∼2% was propagated analytical error. Instantaneous population growth rates measured independently by in vivo fluorescence also varied daily (CV ≈ 53%) and were statistically indistinguishable from single-cell growth rates at all but the lowest levels of cell labeling. SCRR censuses of mixtures prepared from Synechococcus sp. and T. pseudonana (a diatom) populations with varying 13C-content and growth rates closely approximated predicted spectral responses and fractional labeling of cells added to the sample. This approach enables direct microspectrometric interrogation of isotopically- and phylogenetically-labeled cells and detects as little as 3% changes in cellular fractional labeling. This is the first description of a non-destructive technique to measure single-cell photoautotrophic growth rates based on Raman spectroscopy and well-constrained assumptions, while requiring few ancillary measurements

Use of Coronary Computed Tomographic Angiography to guide management of patients with coronary disease

Background In a prospective, multicenter, randomized controlled trial, 4,146 patients were randomized to receive standard care or standard care plus coronary computed tomography angiography (CCTA). Objectives The purpose of this study was to explore the consequences of CCTA-assisted diagnosis on invasive coronary angiography, preventive treatments, and clinical outcomes. Methods In post hoc analyses, we assessed changes in invasive coronary angiography, preventive treatments, and clinical outcomes using national electronic health records. Results Despite similar overall rates (409 vs. 401; p = 0.451), invasive angiography was less likely to demonstrate normal coronary arteries (20 vs. 56; hazard ratios [HRs]: 0.39 [95% confidence interval (CI): 0.23 to 0.68]; p < 0.001) but more likely to show obstructive coronary artery disease (283 vs. 230; HR: 1.29 [95% CI: 1.08 to 1.55]; p = 0.005) in those allocated to CCTA. More preventive therapies (283 vs. 74; HR: 4.03 [95% CI: 3.12 to 5.20]; p < 0.001) were initiated after CCTA, with each drug commencing at a median of 48 to 52 days after clinic attendance. From the median time for preventive therapy initiation (50 days), fatal and nonfatal myocardial infarction was halved in patients allocated to CCTA compared with those assigned to standard care (17 vs. 34; HR: 0.50 [95% CI: 0.28 to 0.88]; p = 0.020). Cumulative 6-month costs were slightly higher with CCTA: difference $462 (95$303 to $621). Conclusions In patients with suspected angina due to coronary heart disease, CCTA leads to more appropriate use of invasive angiography and alterations in preventive therapies that were associated with a halving of fatal and non-fatal myocardial infarction. (Scottish COmputed Tomography of the HEART Trial [SCOT-HEART]; NCT01149590

Authorship representation in global emergency medicine: a bibliometric analysis from 2016 to 2020

Introduction: High-income country (HIC) authors are disproportionately represented in authorship bylines compared with those affiliated with low and middle-income countries (LMICs) in global health research. An assessment of authorship representation in the global emergency medicine (GEM) literature is lacking but may inform equitable academic collaborations in this relatively new field. Methods: We conducted a bibliometric analysis of original research articles reporting studies conducted in LMICs from the annual GEM Literature Review from 2016 to 2020. Data extracted included study topic, journal, study country(s) and region, country income classification, author order, country(s) of authors\u27 affiliations and funding sources. We compared the proportion of authors affiliated with each income bracket using Χ2 analysis. We conducted logistic regression to identify factors associated with first or last authorship affiliated with the study country. Results: There were 14 113 authors in 1751 articles. Nearly half (45.5%) of the articles reported work conducted in lower middle-income countries (MICs), 23.6% in upper MICs, 22.5% in low-income countries (LICs). Authors affiliated with HICs were most represented (40.7%); 26.4% were affiliated with lower MICs, 17.4% with upper MICs, 10.3% with LICs and 5.1% with mixed affiliations. Among single-country studies, those without any local authors (8.7%) were most common among those conducted in LICs (14.4%). Only 31.0% of first authors and 21.3% of last authors were affiliated with LIC study countries. Studies in upper MICs (adjusted OR (aOR) 3.6, 95% CI 2.46 to 5.26) and those funded by the study country (aOR 2.94, 95% CI 2.05 to 4.20) had greater odds of having a local first author. Conclusions: There were significant disparities in authorship representation. Authors affiliated with HICs more commonly occupied the most prominent authorship positions. Recognising and addressing power imbalances in international, collaborative emergency medicine (EM) research is warranted. Innovative methods are needed to increase funding opportunities and other support for EM researchers in LMICs, particularly in LICs