Single contaminant and combined exposures of polyethylene microplastics and fluoranthene: accumulation and oxidative stress response in the blue mussel,Mytilus edulis

The microplastic “vector effect” has received increasing attention. The aim of this study was to investigate the influence of polyethylene microplastic beads (PE MP) on accumulation and associated oxidative stress responses attributed to fluoranthene (Flu) in blue mussels, Mytilus edulis. Blue mussels were exposed for 96 h to four treatment groups: Flu-only, MP-only, Flu and MP coexposure, and Flu-incubated MP. Treatments were conducted at a low and high concentration (50 μg/L and 100 Flu μg/L and 100, and 1000 MP/mL). Results demonstrated that in both the gill and digestive gland, coexposure did not markedly affect Flu uptake, but this treatment significantly decreased tissue Flu concentrations. Antioxidant responses including activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx), and levels of total glutathione (GSH) in both gills and digestive glands were significantly altered suggesting a perturbation of redox state induced by the exposure conditions. Although individual biomarkers varied, the biomarker profile enabled certain generalizations to be made. Antioxidant responses occurred more likely in gill tissue than in digestive gland. Individual contaminant exposures to Flu or MP led to varying responses, but coexposures and incubated exposures did not result in additive or synergistic effects. Exposure concentrations (i.e., low or high treatments) were not a consistent a predictor of response; and the internal Flu dose did not consistently predict outcome of various biomarkers. Importantly, MP-only exposure appeared to be capable of eliciting direct effects on the oxidative stress system as demonstrated by the activities of CAT and GPx. These findings warrant further investigation.     

Microplastic potentiates triclosan toxicity to the marine copepod Acartia tonsa (Dana)

Microplastics (MP) are contaminants of environmental concern partly due to plastics ability to sorb and transport hydrophobic organic contaminants (HOC). The importance of this “vector effect” is currently being debated in the scientific community. This debate largely ignores that the co-exposures of MP and HOC are mixtures of hazardous agents, which can be addressed from a mixture toxicity perspective. In this study, mixture effects of polyethylene microbeads (MP) and triclosan (TCS) (a commonly used antibacterial agent in cosmetics) were assessed on the marine copepod Acartia tonsa. Data indicated that MP potentiate the toxicity of TCS, illustrating the importance of understanding the mixture interaction between plastics and HOC when addressing the environmental importance of the vector effect.     

Gene–environment interactions in panic disorder and CO2 sensitivity: Effects of events occurring early in life

Heterogeneous life events (LE) precede the onset of—and potentially increase the susceptibility to—panic disorder (PD). It remains unknown whether LE can act as moderators in the context of gene‐by‐environment interactions (G×E) that alter the susceptibility to PD and the related trait of CO₂ sensitivity, nor it is known whether such moderation may depend on occurrence of events at different epochs in life. In 712 general population twins we analyzed by Maximum Likelihood analyses of ordinal data whether life (major‐ and stressful) events moderate the genetic risk for PD and CO₂ sensitivity, as indexed by the 35% CO₂/65% O₂ challenge. For CO₂ sensitivity, best‐fitting models encompassed both additive and interactional effects that increased linearly with the cumulative number and severity (SEV) of events in lifetime. By analyzing the moderation effect of cumulative SEV separately for events that had occurred in adulthood (between age 18 and 37) or during childhood–adolescence (before the 18th birthday), we found evidence of G×E only within the childhood–adolescence window of risk, although twins had rated the childhood–adolescence events as significantly (P = 0.001) less severe than those having occurred during adulthood. For PD, all interactional terms could be dropped without significant worsening of the models' fit. Consistently with a diathesis‐stress model, LE appear to act as moderators of the genetic variance for CO₂ sensitivity. Childhood–adolescence appears to constitute a sensitive period to the action of events that concur to alter the susceptibility to this panic‐related trait. © 2010 Wiley‐Liss, Inc.     

Rasch validation of the Danish version of the shoulder pain and disability index (SPADI) in patients with rotator cuff-related disorders

Quality of Life Research - The psychometric properties of the shoulder pain and disability index (SPADI) have been extensively evaluated using classical test theory, but very few studies have...     

Cost-Effectiveness Analysis of Introducing RDTs for Malaria Diagnosis as Compared to Microscopy and Presumptive Diagnosis in Central and Peripheral Public Health Facilities in Ghana

Cost-effectiveness information on where malaria rapid diagnostic tests (RDTs) should be introduced is limited. We developed incremental cost-effectiveness analyses with data from rural health facilities in Ghana with and without microscopy. In the latter, where diagnosis had been presumptive, the introduction of RDTs increased the proportion of patients who were correctly treated in relation to treatment with antimalarials, from 42% to 65% at an incremental societal cost of Ghana cedis (GHS)12.2 (US$8.3) per additional correctly treated patients. In the “microscopy setting” there was no advantage to replacing microscopy by RDT as the cost and proportion of correctly treated patients were similar. Results were sensitive to a decrease in the cost of RDTs, which cost GHS1.72 (US$1.17) per test at the time of the study and to improvements in adherence to negative tests that was just above 50% for both RDTs and microscopy.     

Treatments for Shoulder Impingement Syndrome: A PRISMA Systematic Review and Network Meta-Analysis

Many treatments for shoulder impingement syndrome (SIS) are available in clinical practice; some of which have already been compared with other treatments by various investigators. However, a comprehensive treatment comparison is lacking.Several widely used electronic databases were searched for eligible studies. The outcome measurements were the pain score and the Constant–Murley score (CMS). Direct comparisons were performed using the conventional pair-wise meta-analysis method, while a network meta-analysis based on the Bayesian model was used to calculate the results of all potentially possible comparisons and rank probabilities.Included in the meta-analysis procedure were 33 randomized controlled trials involving 2300 patients. Good agreement was demonstrated between the results of the pair-wise meta-analyses and the network meta-analyses. Regarding nonoperative treatments, with respect to the pain score, combined treatments composed of exercise and other therapies tended to yield better effects than single-intervention therapies. Localized drug injections that were combined with exercise showed better treatment effects than any other treatments, whereas worse effects were observed when such injections were used alone. Regarding the CMS, most combined treatments based on exercise also demonstrated better effects than exercise alone. Regarding surgical treatments, according to the pain score and the CMS, arthroscopic subacromial decompression (ASD) together with treatments derived from it, such as ASD combined with radiofrequency and arthroscopic bursectomy, showed better effects than open subacromial decompression (OSD) and OSD combined with the injection of platelet-leukocyte gel. Exercise therapy also demonstrated good performance. Results for inconsistency, sensitivity analysis, and meta-regression all supported the robustness and reliability of these network meta-analyses.Exercise and other exercise-based therapies, such as kinesio taping, specific exercises, and acupuncture, are ideal treatments for patients at an early stage of SIS. However, low-level laser therapy and the localized injection of nonsteroidal anti-inflammatory drugs are not recommended. For patients who have a long-term disease course, operative treatments may be considered, with standard ASD surgery preferred over arthroscopic bursectomy and the open surgical technique for subacromial decompression. Notwithstanding, the choice of surgery should be made cautiously because similar outcomes may also be achieved by the implementation of exercise therapy.     

Survival and Morbidity Following Congenital Heart Surgery in a Population‐based Cohort of Children—up to 12 Years of Follow‐up

Objectives. The Risk Adjusted Classification for Congenital Heart Surgery can predict early mortality. However, the relation to long‐term outcome in terms of mortality and morbidity is unknown. Design. We did a population‐based follow‐up study of 801 children undergoing congenital heart surgery between 1996 and 2002. All patients were followed from surgery until death or January 1, 2008. Operations were classified according to the Risk Adjusted Classification for Congenital Heart Surgery. Each patient was matched by age and sex with 10 population controls. Cox regression analysis, area under the receiver operator curve and competing risk analysis were used for the analyses. Results. Overall follow‐up was 99.6%. The distribution of the Risk Adjusted Classification for Congenital Heart Surgery was: Category one 20%, category two 37%, category three 27%, category four 8%, category five 0% and category six 2%. Overall survival after a median follow‐up of 8.2 years was 86% (95% confidence interval: 83–88%), with 54 early deaths occurring within 30 days after surgery and 57 late deaths. Long‐term survival in those who were alive 30 days after surgery was 92% (90–94%); ranging from 98% (93–100%) in risk category one to 33% (5–68%) in category six. Survival overall and beyond 30 days was lower in each risk category than in controls (P < .001). During follow‐up, 124 (15%) patients had new operations and 106 (13%) catheter‐based interventions. These events were more frequent in category three, four, and six compared with category one, with no difference between category one and two. The area under the receiver operator curve for long‐term mortality was 0.81 (95% confidence interval 0.75–0.87). Conclusions. Children operated for congenital heart disease have impaired survival and often undergo new operations or catheter‐based interventions. The risk of these events is related to the surgical complexity according to the Risk Adjusted Classification for Congenital Heart Surgery.