Comparing the Invasibility of Experimental “Reefs” with Field Observations of Natural Reefs and Artificial Structures

Natural systems are increasingly being modified by the addition of artificial habitats which may facilitate invasion. Where invaders are able to disperse from artificial habitats, their impact may spread to surrounding natural communities and therefore it is important to investigate potential factors that reduce or enhance invasibility. We surveyed the distribution of non-indigenous and native invertebrates and algae between artificial habitats and natural reefs in a marine subtidal system. We also deployed sandstone plates as experimental ‘reefs’ and manipulated the orientation, starting assemblage and degree of shading. Invertebrates (non-indigenous and native) appeared to be responding to similar environmental factors (e.g. orientation) and occupied most space on artificial structures and to a lesser extent reef walls. Non-indigenous invertebrates are less successful than native invertebrates on horizontal reefs despite functional similarities. Manipulative experiments revealed that even when non-indigenous invertebrates invade vertical “reefs”, they are unlikely to gain a foothold and never exceed covers of native invertebrates (regardless of space availability). Community ecology suggests that invertebrates will dominate reef walls and algae horizontal reefs due to functional differences, however our surveys revealed that native algae dominate both vertical and horizontal reefs in shallow estuarine systems. Few non-indigenous algae were sampled in the study, however where invasive algal species are present in a system, they may present a threat to reef communities. Our findings suggest that non-indigenous species are less successful at occupying space on reef compared to artificial structures, and manipulations of biotic and abiotic conditions (primarily orientation and to a lesser extent biotic resistance) on experimental “reefs” explained a large portion of this variation, however they could not fully explain the magnitude of differences

How Do They Do It? – Understanding the Success of Marine Invasive Species

From the depths of the oceans to the shallow estuaries and wetlands of our coasts, organisms of the marine environment are teeming with unique adaptations to cope with a multitude of varying environmental conditions. With millions of years and a vast volume of water to call their home, they have become quite adept at developing specialized and unique techniques for survival and – given increasing human mediated transport – biological invasions. A growing world human population and a global economy drives the transportation of goods across the oceans and with them invasive species via ballast water and attached to ship hulls. In any given 24-hour period, there are about 10,000 species being transported across different biogeographic regions. If any of them manage to take hold and establish a range in an exotic habitat, the implications for local ecosystems can be costly. This review on marine invasions highlights trends among successful non-indigenous species (NIS), from vectors of transport to ecological and physiological plasticity. Apart from summarizing patterns of successful invasions, it discusses the implications of how successfully established NIS impact the local environment, economy and human health. Finally, it looks to the future and discusses what questions need to be addressed and what models can tell us about what the outlook on future marine invasions is

‘Minimal symptom expression’ in patients with acetylcholine receptor antibody-positive refractory generalized myasthenia gravis treated with eculizumab

Background: The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension. Methods: Attainment of ‘minimal symptom expression’ was evaluated using patient-reported outcome measures of gMG symptoms [MG activities of daily living scale (MG-ADL), 15-item MG quality of life questionnaire (MG-QOL15)] at the completion of REGAIN and during the open-label extension. ‘Minimal symptom expression’ was defined as MG-ADL total score of 0–1 or MG-QOL15 total score of 0–3. Results: At REGAIN week 26, more eculizumab-treated patients achieved ‘minimal symptom expression’ versus placebo [MG-ADL: 21.4% vs 1.7%; difference 19.8%; 95% confidence interval (CI) 8.5, 31.0; p = 0.0007; MG-QOL15: 16.1% vs 1.7%; difference 14.4%; 95% CI 4.3, 24.6; p = 0.0069]. During the open-label extension, the proportion of patients in the placebo/eculizumab group who achieved ‘minimal symptom expression’ increased after initiating eculizumab treatment and was sustained through 130 weeks of open-label eculizumab (MG-ADL: 1.7 to 27.8%; MG-QOL15: 1.7 to 19.4%). At extension study week 130, similar proportions of patients in the eculizumab/eculizumab and placebo/eculizumab groups achieved ‘minimal symptom expression’ (MG-ADL: 22.9% and 27.8%, respectively, p = 0.7861; MG-QOL15: 14.3% and 19.4%, respectively, p = 0.7531). The long-term tolerability of eculizumab was consistent with previous reports. Conclusions: Patients with AChR+ refractory gMG who receive eculizumab can achieve sustained ‘minimal symptom expression’ based on patient-reported outcomes. ‘Minimal symptom expression’ may be a useful tool in measuring therapy effectiveness in gMG. Trial registration: ClinicalTrials.gov NCT01997229, NCT02301624

Correction to: Eculizumab improves fatigue in refractory generalized myasthenia gravis (Quality of Life Research, (2019), 28, 8, (2247-2254), 10.1007/s11136-019-02148-2)

The article “Eculizumab improves fatigue in refractory generalized myasthenia gravis”, written by “Henning Andersen, Renato Mantegazza, Jing Jing Wang, Fanny O’Brien, Kaushik Patra, James F. Howard Jr. and The REGAIN Study Group” was originally published electronically on the publisher’s internet portal (currently SpringerLink) on 23 March 2019 without open access

Eculizumab improves fatigue in refractory generalized myasthenia gravis

To evaluate the effect of eculizumab on perceived fatigue in patients with anti-acetylcholine receptor antibody-positive, refractory, generalized myasthenia gravis (MG) using the Quality of Life in Neurological Disorders (Neuro-QOL) Fatigue subscale, and to evaluate correlations between improvements in Neuro-QOL Fatigue and other clinical endpoints.Purpose: To evaluate the effect of eculizumab on perceived fatigue in patients with anti-acetylcholine receptor antibody-positive, refractory, generalized myasthenia gravis (MG) using the Quality of Life in Neurological Disorders (Neuro-QOL) Fatigue subscale, and to evaluate correlations between improvements in Neuro-QOL Fatigue and other clinical endpoints. Methods: Neuro-QOL Fatigue, MG Activities of Daily Living (MG-ADL), Quantitative MG (QMG), and the 15-item MG Quality of Life (MG-QOL15) scales were administered during the phase 3, randomized, placebo-controlled REGAIN study (eculizumab, n = 62; placebo, n = 63) and subsequent open-label extension (OLE). Data were analyzed using repeated-measures models. Correlations between changes in Neuro-QOL Fatigue and in MG-ADL, QMG, and MG-QOL15 scores were determined at REGAIN week 26. Results: At REGAIN week 26, eculizumab-treated patients showed significantly greater improvements in Neuro-QOL Fatigue scores than placebo-treated patients (consistent with improvements in MG-ADL, QMG, and MG-QOL15 scores previously reported in REGAIN). Improvements with eculizumab were sustained through OLE week 52. Correlations between Neuro-QOL Fatigue and MG-QOL15, MG-ADL, and QMG scores were strong for eculizumab-treated patients at REGAIN week 26, and strong, moderate, and weak, respectively, for placebo-treated patients. Conclusions: Compared with placebo, eculizumab was associated with improvements in perceived fatigue that strongly correlated with improvements in MG-specific outcome measures. Trial ID Registration: NCT01997229, NCT02301624