Floral ontogeny in Dialiinae (Caesalpinioideae: Cassieae), a study in organ loss and instability

AbstractThe Caesalpinioideae are widely variable in their floral ontogeny, and among caesalpinioids, members of the polyphyletic tribe Cassieae are particularly diverse. Within the Cassieae, the monophyletic Dialiinae clade is also marked by a high degree of organ loss, particularly in the largest genus, Dialium. The purpose of this work is to explore the ontogeny of several previously undocumented species of the diverse Dialiinae clade, with the goal of building a more complete picture of floral development and evolution in this group and especially within Dialium. We have documented the floral ontogeny of six species of the Dialiinae; four from Dialium, as well as Poeppigia procera and Mendoravia dumaziana. Mode and timing of organ initiation were mostly consistent across the Dialium species studied. With the exception of Dialium dinklagei, which undergoes helical calyx initiation, all flowers initiated sepals bidirectionally. In the instances of both gains and losses of floral organs in Dialium, one trend is apparent — an absence of abaxial organs. Gains in both sepals and stamens occur in the adaxial median position, while stamens and petals which are lost are always the ventral-most organs. Organ initiation in Poeppigia and Mendoravia is unlike that seen in Dialium. Poeppigia shows a ventral to dorsal unidirectional sepal initiation, while both Poeppigia and Mendoravia display near-synchronous initiation of the corolla and staminal whorls. The taxa examined here exemplify the apparent lack of developmental canalisation seen in caesalpinioid legumes. This ontogenetic plasticity is reflective of the morphological diversity shown by flowers across the subfamily, representing what has been described as an “experimental” phase in legume floral evolution

Peripheral Determinants of Oxygen Utilization in Heart Failure With Preserved Ejection Fraction

The aim of this study was to determine the arteriovenous oxygen content difference (ΔAVO2) in adult subjects with and without heart failure with preserved ejection fraction (HFpEF) during systemic and forearm exercise. Subjects with HFpEF had reduced ΔAVO2. Forearm diffusional conductance for oxygen, a lumped conductance parameter that incorporates all impediments to the movement of oxygen from red blood cells in skeletal muscle capillaries into the mitochondria within myocytes, was estimated. Forearm diffusional conductance for oxygen was not different among adults with HFpEF, those with hypertension, and healthy control subjects; therefore, diffusional conductance cannot explain the reduced forearm ΔAVO2. Instead, adiposity was strongly associated with ΔAVO2, suggesting an active role for adipose tissue in reducing exercise capacity in patients with HFpEF

Phospholipid dependent mechanism of smp24, an α-helical antimicrobial peptide from scorpion venom

Determining the mechanism of action of antimicrobial peptides (AMPs) is critical if they are to be developed into the clinical setting. In recent years high resolution techniques such as atomic force microscopy (AFM) have increasingly been utilised to determine AMP mechanism of action on planar lipid bilayers and live bacteria. Here we present the biophysical characterisation of a prototypical AMP from the venom of the North African scorpion Scorpio maurus palmatus termed Smp24. Smp24 is an amphipathic helical peptide containing 24 residues with a charge of + 3 and exhibits both antimicrobial and cytotoxic activity and we aim to elucidate the mechanism of action of this peptide on both membrane systems. Using AFM, quartz crystal microbalance-dissipation (QCM-D) and liposomal leakage assays the effect of Smp24 on prototypical synthetic prokaryotic (DOPG:DOPC) and eukaryotic (DOPE:DOPC) membranes has been determined. Our data points to a toroidal pore mechanism against the prokaryotic like membrane whilst the formation of hexagonal phase non-lamellar phase structures is seen in eukaryotic like membrane. Also, phase segregation is observed against the eukaryotic membrane and this study provides direct evidence of the same peptide having multiple mechanisms of action depending on the membrane lipid composition

A limited and customized follow-up seems justified after endovascular abdominal aneurysm repair in octogenarians

ObjectiveThe objective of this study was to determine whether long-term follow-up after endovascular aneurysm repair (EVAR) is justified in octogenarians.MethodsBetween September 1996 and October 2011, all patients, including octogenarians, treated for an abdominal aortic aneurysm (AAA) by EVAR were included in a prospective database. Patients older than 80 years and with a nonruptured infrarenal aneurysm treated electively or urgently were included in the study (study group [SG]). Patients with ruptured aneurysms and patients who died during surgery or within the first postoperative month were excluded from further analysis. The control group (CG) consisted of patients younger than 80 years, matched for gender and AAA diameter. All patients were evaluated 4 to 8 weeks after EVAR and then annually thereafter. Follow-up data were complemented by review of the computerized hospital registry and charts and by contact of the patient's general practitioner or referring hospital. Primary outcomes were stent- or aneurysm-related complications and interventions. Secondary outcomes were additional surgical complications and patient survival.ResultsA total number of 193 patients (SG, n = 97; CG, n = 96) were included for analysis. Median age was 80 years, and 88.6% were male. Median follow-up time was 33.6 months (interquartile range [IQR], 12.9-68.3). Stent- and procedure-related postoperative complications were comparable between groups (SG, 41.2%; CG, 39.6%; P = .82). Median time to complication was 2.3 months (IQR, 0.2-19.4) in the SG compared with 18.1 months (IQR, 6.8-50.5) in the CG. The 2-year complication-free survival rates were 58% (SG) and 60% (CG). Interventions were performed significantly less frequently in octogenarians (SG, 8.2%; CG, 19.8%; P < .05). Median time to intervention was 11.1 months (IQR, 2.0-31.0) in the SG compared with 54.3 months (IQR, 15.0-93.2) in the CG. The 2-year intervention-free survival rates were 90% (SG) and 92% (CG). During follow-up, 98 patients died (SG, n = 54; CG, n = 44); median time to death was 31.8 months (IQR, 13.3-66.0) in the SG compared with 44.4 months (IQR, 15.0-77.7) in the CG. One aneurysm-related death occurred in the CG. The 2- and 5-year survival rates were 71% and 32% for the SG compared with 77% and 66% for the CG (P < .05).ConclusionsBecause of the low incidence of secondary procedures and AAA-related deaths in octogenarians, long-term and frequent follow-up after EVAR seems questionable. An adapted and shortened follow-up seems warranted in this patient group

Postinjection Endophthalmitis in the Comparison of Age-Related Macular Degeneration Treatments Trials (CATT)

To describe the incidence and outcomes of endophthalmitis after intravitreal injections of anti-VEGF agents in the Comparison of Age-related Macular Degeneration Treatments Trials (CATT) and to assess the effect of use of prophylactic topical antimicrobials on incidence

Extent of non-publication in cohorts of studies approved by research ethics committees or included in trial registries

BACKGROUND: The synthesis of published research in systematic reviews is essential when providing evidence to inform clinical and health policy decision-making. However, the validity of systematic reviews is threatened if journal publications represent a biased selection of all studies that have been conducted (dissemination bias). To investigate the extent of dissemination bias we conducted a systematic review that determined the proportion of studies published as peer-reviewed journal articles and investigated factors associated with full publication in cohorts of studies (i) approved by research ethics committees (RECs) or (ii) included in trial registries. METHODS AND FINDINGS: Four bibliographic databases were searched for methodological research projects (MRPs) without limitations for publication year, language or study location. The searches were supplemented by handsearching the references of included MRPs. We estimated the proportion of studies published using prediction intervals (PI) and a random effects meta-analysis. Pooled odds ratios (OR) were used to express associations between study characteristics and journal publication. Seventeen MRPs (23 publications) evaluated cohorts of studies approved by RECs; the proportion of published studies had a PI between 22% and 72% and the weighted pooled proportion when combining estimates would be 46.2% (95% CI 40.2%-52.4%, I2 = 94.4%). Twenty-two MRPs (22 publications) evaluated cohorts of studies included in trial registries; the PI of the proportion published ranged from 13% to 90% and the weighted pooled proportion would be 54.2% (95% CI 42.0%-65.9%, I2 = 98.9%). REC-approved studies with statistically significant results (compared with those without statistically significant results) were more likely to be published (pooled OR 2.8; 95% CI 2.2-3.5). Phase-III trials were also more likely to be published than phase II trials (pooled OR 2.0; 95% CI 1.6-2.5). The probability of publication within two years after study completion ranged from 7% to 30%. CONCLUSIONS: A substantial part of the studies approved by RECs or included in trial registries remains unpublished. Due to the large heterogeneity a prediction of the publication probability for a future study is very uncertain. Non-publication of research is not a random process, e.g., it is associated with the direction of study findings. Our findings suggest that the dissemination of research findings is biased

Parameters affecting water-hammer wave attenuation, shape and timing. Part 2: Case studies

This two-part paper investigates parameters that may significantly affect water-hammer wave attenuation, shape and timing. Possible sources that may affect the waveform predicted by classical water-hammer theory include unsteady friction, cavitation (including column separation and trapped air pockets), a number of fluid–structure interaction effects, viscoelastic behaviour of the pipe-wall material, leakages and blockages. Part 1 of this two-part paper presents the mathematical tools needed to model these sources. Part 2 of the paper presents a number of case studies showing how these modelled sources affect pressure traces in a simple reservoir-pipeline-valve system. Each case study compares the obtained results with the standard (classical) water-hammer model, from which conclusions are drawn concerning the transient behaviour of real systems.Anton Bergant, Arris S. Tijsseling, John P. Vítkovský, Dídia I. C. Covas, Angus R. Simpson and Martin F. Lamber