Cost-effectiveness of dapagliflozin for patients with heart failure across the spectrum of ejection fraction: A pooled analysis of DAPA-HF and DELIVER data

AIM

To assess the cost-effectiveness of dapagliflozin in addition to usual care, compared with usual care alone, in a large population of patients with heart failure (HF), spanning the full range of left ventricular ejection fraction (LVEF).

METHODS AND RESULTS

Patient-level data were pooled from HF trials (DAPA-HF, DELIVER) to generate a population including HF with reduced, mildly reduced and preserved LVEF, to increase statistical power and enable exploration of interactions among LVEF, renal function and N-terminal pro-B-type natriuretic peptide levels, as they are relevant determinants of health status in this population. Survival and HF recurrent event risk equations were derived and applied to a lifetime horizon Markov model with health states defined by Kansas City Cardiomyopathy Questionnaire total symptom score quartiles; costs and utilities were in the UK setting. The base case incremental cost-effectiveness ratio (ICER) was £6470 per quality-adjusted life year (QALY) gained, well below the UK willingness-to-pay (WTP) threshold of £20 000/QALY gained. In interaction sensitivity analyses, the highest ICER was observed for elderly patients with preserved LVEF (£16 624/QALY gained), and ranged to a region of dominance (increased QALYs, decreased costs) for patients with poorer renal function and reduced/mildly reduced LVEF. Results across the patient characteristic interaction plane were mostly between £5000 and £10 000/QALY gained.

CONCLUSIONS

Dapagliflozin plus usual care, versus usual care alone, yielded results well below the WTP threshold for the UK across a heterogeneous population of patients with HF including the full spectrum of LVEF, and is likely a cost-effective intervention.

Dapagliflozin in chronic kidney disease: cost-effectiveness beyond the DAPA-CKD trial

Background

The Dapagliflozin and Prevention of Adverse Outcomes in CKD (DAPA-CKD) trial enrolled patients with estimated glomerular filtration rate 25-75 mL/min/1.73 m2 and urine albumin-to-creatinine ratio >200 mg/g. The Dapagliflozin Effect on CardiovascuLAR Events-Thrombolysis in Myocardial Infarction 58 (DECLARE-TIMI 58) trial enrolled patients with type 2 diabetes, a higher range of kidney function and no albuminuria criterion. The study objective was to estimate the cost-effectiveness of dapagliflozin in a broad chronic kidney disease population based on these two trials in the UK, Spain, Italy and Japan.

Methods

We adapted a published Markov model based on the DAPA-CKD trial but to a broader population, irrespective of urine albumin-to-creatinine ratio, using patient-level data from the DAPA-CKD and DECLARE-TIMI 58 trials. We sourced cost and utility inputs from literature and the DAPA-CKD trial. The analysis considered healthcare system perspectives over a lifetime horizon.

Results

Treatment with dapagliflozin was predicted to attenuate disease progression and extend projected life expectancy by 0.64 years (12.5 versus 11.9 years, undiscounted) in the UK, with similar estimates in other settings. Clinical benefits translated to mean quality-adjusted life year (QALY; discounted) gains between 0.45 and 0.68 years across countries. Incremental cost-effectiveness ratios in the UK, Spain, Italy and Japan ($10 676/QALY, $14 479/QALY, $7771/QALY and $13 723/QALY, respectively) were cost-effective at country-specific willingness-to-pay thresholds. Subgroup analyses suggest dapagliflozin is cost-effective irrespective of urinary albumin-to-creatine ratio and type 2 diabetes status.

Conclusion

Treatment with dapagliflozin may be cost-effective for patients across a wider spectrum of estimated glomerular filtration rates and albuminuria than previously demonstrated, with or without type 2 diabetes, in the UK, Spanish, Italian and Japanese healthcare systems.

The cost-effectiveness of dapagliflozin in heart failure with preserved or mildly reduced ejection fraction: A European health-economic analysis of the DELIVER trial

AIMS

To determine the cost-effectiveness of dapagliflozin, added to usual care, in patients with heart failure (HF) with mildly reduced or preserved ejection fraction for the UK, German and Spanish payers using detailed patient-level data from the Dapagliflozin Evaluation to Improve the LIVEs of Patients with Preserved Ejection Fraction Heart Failure (DELIVER) trial.

METHODS AND RESULTS

A lifetime Markov state-transition cohort model was developed. Quartiles of the Kansas City Cardiomyopathy Questionnaire total symptom score (KCCQ-TSS) defined health states and monthly transition count data informed transition probabilities. Multivariable generalized estimating equations captured the incidence of HF hospitalizations and urgent HF visits, while cardiovascular deaths and all-cause mortality were estimated using adjusted parametric survival models. Health state costs were assigned to KCCQ-TSS quartiles (2021 British pound [GBP]/Euro) and patient-reported outcomes were sourced from DELIVER. Future values of costs and effects were discounted according to country-specific rates. In the UK, dapagliflozin treatment was predicted to increase quality-adjusted life years (QALYs) and life-years by 0.231 and 0.354, respectively, and extend the time spent in the best quartile of KCCQ-TSS by 4.2 months. Comparable outcomes were projected for Germany and Spain. The incremental cost-effectiveness ratios were £7761, €9540 and €5343/QALY in the UK, Germany and Spain, respectively. According to regional willingness-to-pay thresholds, 91%, 89% and 92% of simulations in the UK, Germany and Spain, respectively, were cost-effective following probabilistic sensitivity analyses.

CONCLUSION

Dapagliflozin, added to usual care, is very likely cost-effective for HF with mildly reduced or preserved ejection fraction in several European countries.

Field applications of zein as a precise nanoscale delivery system for methoxyfenozide

When insecticides are applied in the environment, much of the product does not reach the target pest. Biopolymeric nanoparticles as nanocarriers have the potential to improve insecticide efficacy by improving absorption, coverage, and permeability while protecting the insecticide active ingredient from abiotic conditions and extending efficacy through controlled release. We conducted a series of experiments using a biopolymeric nanoparticle synthesized from zein, a biodegradable maize protein, to compare efficacy of a nanodelivered hydrophobic insect growth regulator (methoxyfenozide) against a commercial formulation. Positively charged zein nanoparticles (empty and loaded with methoxyfenozide) were compared to the formulated product, Intrepid 2F, as a foliar spray in-field on soybean. Chrysodeixis includens (Walker) was used as a model and was fed sprayed soybean leaves to evaluate efficacy of the tested foliar products over time. A separate set of leaves was sampled to measure residue levels of methoxyfenozide (MFZ) over time following foliar application using QuEChERS extraction and high-resolution liquid chromatography-mass spectrometry. Regression analysis found no differences in mortality slopes between positively charged zein nanoparticles loaded with methoxyfenozide [(+)ZNP(MFZ)] and Intrepid 2F, suggesting comparable efficacy of the synthesized nanoparticles to a commercial product. Higher concentrations of MFZ were present in (+)ZNP(MFZ)-treated in leaf tissue at 3 d following spray when compared to Intrepid 2F. The multiyear study results demonstrate that nanoparticles loaded with MFZ are comparable to Intrepid 2F under field conditions, with potential short-term benefits.

Use of the Hybrid Operating Room for Pelvic and Acetabular Fracture Surgery

The hybrid operating room (HOR) utilizes advanced imaging technology to improve intra-operative visualization and facilitate efficient care in procedures that are relatively image dependent. The robotic C-arm provides improved 2D image quality and is capable of large volume three-dimensional fluoroscopy (3DF) that can rapidly create multiplanar CT like images. Here we discuss on the technique, utility, potential benefits, pitfalls, and complications of using the hybrid suite with and without intra-arterial balloon occlusion for pelvic and acetabular fracture surgery. We also present a case series of patient who underwent pelvic fixation using the HOR. While not advocated for routine use in all pelvic and acetabular fractures; the hybrid suite can be an effective tool in the treatment of complex cases and may facilitate efficient care of the hemodynamically unstable patient. It should be considered when resuscitative stabilization, angioembolization, intra-arterial balloon occlusion, or life-threatening bleeding is anticipated. Additionally, use of the hybrid room allows access to 3D fluoroscopy, and the associated benefits, if a mobile 3D unit is otherwise unavailable. These benefits must be weighed against the cumbersome table, the potential pitfalls with patient size and positioning, and the increased cost to the hospital.

Belowground Herbivory to Sweetpotato by Sweetpotato Weevil (Coleoptera: Brentidae) Alters Population Dynamics and Probing Behavior of Aboveground Herbivores

Aboveground and belowground herbivory can alter host quality and trophic interactions. However, little research has explored the impacts of belowground herbivory on plant virus epidemiology. To understand this interaction in sweetpotato, Ipomoea batatas L. (Lam), we studied the impact of herbivory by sweetpotato weevil, Cylas formicarius elegantulus (Summers), to storage roots on vector herbivore, Myzus persicae (Sulzer), the green peach aphid, and Aphis gossypii Glover, the cotton aphid, feeding behavior (M. persicae and A. gossypii) and population dynamics (M. persicae only as A. gossypii does not colonize sweetpotato). In addition, a nonvector herbivore, Chrysodeixis includens (Walker), the soybean looper, weight gain was included for comparison. Infestations of sweetpotato weevil in storage roots reduced C. includens weight gain and M. persicae intrinsic rate of increase (rm), net reproductive rate (Ro), and finite rate of increase (λ) on aboveground portions of the plant. In probing behaviors related to nonpersistent virus spread (30 min trials), M. persicae probed less often, took longer to reach the first pd (potential drop), had shorter II-3 (intracellular subphase sap ingestion) durations, and had fewer archlets on plants infested with C. formicarius elegantulus. Total phloem duration did not differ between treatments, indicating that the lowered performance of M. persicae on infested plants was not due to discrepancies in probing duration. Results were less clear for A. gossypii. Thus, in sweetpotato, belowground herbivory can alter plant virus vector abundance and behavior. Understanding the mechanisms underlying these changes in behavior could improve plant virus vector integrated pest management.

Proportional-assist ventilation with load-adjustable gain factors for mechanical ventilation: a cost-utility analysis

BACKGROUND

Mechanical ventilation is an important component of patient critical care, but it adds expense to an already high-cost setting. This study evaluates the cost-utility of 2 modes of ventilation: proportional-assist ventilation with load-adjustable gain factors (PAV+ mode) versus pressure-support ventilation (PSV).

METHODS

We adapted a published Markov model to the Canadian hospital-payer perspective with a 1-year time horizon. The patient population modelled includes all patients receiving invasive mechanical ventilation who have completed the acute phase of ventilatory support and have entered the recovery phase. Clinical and cost inputs were informed by a structured literature review, with the comparative effectiveness of PAV+ mode estimated via pragmatic meta-analysis. Primary outcomes of interest were costs, quality-adjusted life years (QALYs) and the (incremental) cost per QALY for patients receiving mechanical ventilation. Results were reported in 2017 Canadian dollars. We conducted probabilistic and scenario analyses to assess model uncertainty.

RESULTS

Over 1 year, PSV had costs of $50 951 and accrued 0.25 QALYs. Use of PAV+ mode was associated with care costs of $43 309 and 0.29 QALYs. Compared to PSV, PAV+ mode was considered likely to be cost-effective, having lower costs (-$7642) and increased QALYs (+0.04) after 1 year. In cost-effectiveness acceptability analysis, 100% of simulations would be cost-effective at a willingness-to-pay threshold of $50 000 per QALY gained.

INTERPRETATION

Use of PAV+ mode is expected to benefit patient care in the intensive care unit (ICU) and be a cost-effective alternative to PSV in the Canadian setting. Canadian hospital payers may therefore consider how best to optimally deliver mechanical ventilation in the ICU as they expand ICU capacity.

The role of diet quality and dietary patterns in predicting muscle mass and function in men over a 15-year period

A growing body of evidence suggests that diet quality may predict muscle health. This study found that a "Traditional" dietary pattern predicted greater muscle mass, and an anti-inflammatory diet predicted greater muscle mass and better muscle function over 15 years. These findings reinforce the importance of optimising dietary behaviours for healthy ageing.

INTRODUCTION

Research investigating the roles of individual nutrients in muscle health fails to account for the synergistic relationships between foods and nutrients. This study aimed to investigate the predictive value of diet quality and dietary patterns for muscle mass and function in men over a 15-year period.

METHODS

This longitudinal study was conducted in 522 men from the Geelong Osteoporosis Study with complete dietary and muscle mass or muscle function data at both baseline and 15-year follow-up assessments. Dietary exposures were extracted from food frequency questionnaires and included the Australian Recommended Food Score, the Dietary Inflammatory Index (DII®), and three a posteriori dietary patterns: Plant-focused, Western, and Traditional (Anglo-Australian). Outcome variables included dual-energy X-ray absorptiometry-derived skeletal muscle index (SMI) and muscle function measured with the timed up-and-go (TUG) test.

RESULTS

An anti-inflammatory diet and higher scores on a Traditional dietary pattern both predicted greater SMI ((B: -0.04 (95%CI -0.08, -0.00) kg/m²) and (B: 0.12 (95%CI 0.04, 0.20) kg/m²), respectively), while a pro-inflammatory diet predicted slower TUG (B: 0.11 (95%CI 0.001, 0.21) sec) over the 15-year follow-up period. These associations remained significant following adjustment for confounding variables. There were no associations observed for other dietary exposures.

CONCLUSION

A Traditional dietary pattern higher in vegetables, wholegrain cereals, and animal protein was associated with greater skeletal muscle mass, and an anti-inflammatory diet, also rich in vegetables, fruit, and wholegrain cereals, was associated with greater skeletal muscle mass and better muscle function over 15 years.

Delayed debridement of open tibia fractures beyond 24 and 48 h does not appear to increase infection and reoperation risk

PURPOSE

Surgical debridement is critical to the treatment of open tibia fractures, although the effects of delayed debridement have not been well-established. Other factors such as Gustilo-Anderson type, prompt initiation of antibiotics, and time to definitive closure may be more predictive of infection than time to surgery. We sought to determine the effect of a prolonged delay to surgical debridement with respect to infection and reoperation rates for open tibia fractures.

METHODS

All open diaphyseal tibia fractures with > 12-week follow-up were evaluated. Patient demographics, Gustilo-Anderson type, and rates of deep infection and all-cause reoperation were recorded. Patients were divided into 3 groups based on time to surgery: early (< 24 h), delayed (24-48 h), and late (> 48 h). Univariate and multivariate analyses were performed to evaluate the relationship between time to surgery, fracture type, infection, and reoperation.

RESULTS

In total, 96 open tibia fractures with average follow-up of 59.3 weeks and infection rate of 13.5% were included. Infection rates for the early, delayed, and late groups were 13.3%, 17.2%, and 9.1%, respectively (p = 0.70). Reoperation rates for the early, delayed, and late groups were 29.8%, 31.0%, and 22.7%, respectively (p = 0.80). The groups did not vary in proportion of Gustilo-Anderson fracture types; infection rates between Gustilo-Anderson types were similar (p = 0.57). Type IIIA-C fractures required more reoperations than other fracture types (p = 0.01).

CONCLUSION

Delayed surgical debridement of open tibia fractures did not result in greater rates of infection or reoperation. Gustilo-Anderson classification was more predictive of reoperation, with Type IIIA-C injuries having a significantly higher reoperation rate.

Ferric carboxymaltose for the treatment of iron deficiency in heart failure: a multinational cost-effectiveness analysis utilising AFFIRM-AHF

Aims

Iron deficiency is common in patients with heart failure (HF). In AFFIRM‐AHF, ferric carboxymaltose (FCM) reduced the risk of hospitalisations for HF (HHF) and improved quality of life vs. placebo in iron‐deficient patients with a recent episode of acute HF. The objective of this study was to estimate the cost‐effectiveness of FCM compared with placebo in iron‐deficient patients with left ventricular ejection fraction <50%, stabilised after an episode of acute HF, using data from the AFFIRM‐AHF trial from Italian, UK, US and Swiss payer perspectives.

Methods and results

A lifetime Markov model was built to characterise outcomes in patients according to the AFFIRM‐AHF trial. Health states were defined using the 12‐item Kansas City Cardiomyopathy Questionnaire (KCCQ‐12). Subsequent HHF were incorporated using a negative binomial regression model with cardiovascular and all‐cause mortality incorporated via parametric survival analysis. Direct healthcare costs (2020 GBP/USD/EUR/CHF) and utility values were sourced from published literature and AFFIRM‐AHF. Modelled outcomes indicated that treatment with FCM was dominant (cost saving with additional health gains) in the UK, USA and Switzerland, and highly cost‐effective in Italy [incremental cost‐effectiveness ratio (ICER) EUR 1269 per quality‐adjusted life‐year (QALY)]. Results were driven by reduced costs for HHF events combined with QALY gains of 0.43–0.44, attributable to increased time in higher KCCQ states (representing better functional outcomes). Sensitivity and subgroup analyses demonstrated data robustness, with the ICER remaining dominant or highly cost‐effective under a wide range of scenarios, including increasing treatment costs and various patient subgroups, despite a moderate increase in costs for de novo HF and smaller QALY gains for ischaemic aetiology.

Conclusion

Ferric carboxymaltose is estimated to be a highly cost‐effective treatment across countries (Italy, UK, USA and Switzerland) representing different healthcare systems.

Characterizing Host Plant Resistance to Melanaphis sacchari (Hemiptera: Aphididae) in Selected Sorghum Plant Introductions

Since 2013 Melanaphis sacchari (Zehnter) (Hemiptera: Aphididae), the sugarcane aphid, has been a threat to sorghum production in the United States. The development of resistant sorghum hybrids has been one of the main management strategies. However, plant resistance can be overcome over time and new resistance genes need to be identified and introduced into adapted sorghum hybrids to secure sorghum production. Sorghum plant introduction (PI) genotypes were screened for resistance to M. sacchari through laboratory, greenhouse, and field assays. In addition, the feeding parameters of M. saccahri were analyzed and detailed in seven sorghum genotypes through EPG assays. Results showed sorghum genotypes PI 524770, PI 564163, and PI 643515 expressed resistance to M. sacchari consistently in laboratory, greenhouse, and field tests. EPG analysis suggested sorghum genotypes PI 524770 and PI 564163 express antibiosis to M. sacchari while PI 643515 expresses both antibiosis and antixenosis. Increasing the number of sorghum hybrids resistant to M. sacchari is key to improving integrated pest management of M. sacchari. By utilizing host plant resistance, sorghum producers can decrease insecticide applications while enhancing biological control.

Study of the X-ray radiation interaction with a multislit collimator for the creation of microbeams in radiation therapy

Microbeam radiation therapy (MRT) is a developing radiotherapy, based on the use of beams only a few tens of micrometres wide, generated by synchrotron X-ray sources. The spatial fractionation of the homogeneous beam into an array of microbeams is possible using a multislit collimator (MSC), i.e. a machined metal block with regular apertures. Dosimetry in MRT is challenging and previous works still show differences between calculated and experimental dose profiles of 10-30%, which are not acceptable for a clinical implementation of treatment. The interaction of the X-rays with the MSC may contribute to the observed discrepancies; the present study therefore investigates the dose contribution due to radiation interaction with the MSC inner walls and radiation leakage of the MSC. Dose distributions inside a water-equivalent phantom were evaluated for different field sizes and three typical spectra used for MRT studies at the European Synchrotron Biomedical beamline ID17. Film dosimetry was utilized to determine the contribution of radiation interaction with the MSC inner walls; Monte Carlo simulations were implemented to calculate the radiation leakage contribution. Both factors turned out to be relevant for the dose deposition, especially for small fields. Photons interacting with the MSC walls may bring up to 16% more dose in the valley regions, between the microbeams. Depending on the chosen spectrum, the radiation leakage close to the phantom surface can contribute up to 50% of the valley dose for a 5 mm × 5 mm field. The current study underlines that a detailed characterization of the MSC must be performed systematically and accurate MRT dosimetry protocols must include the contribution of radiation leakage and radiation interaction with the MSC in order to avoid significant errors in the dose evaluation at the micrometric scale.

Earlier Provision of Gastric Bypass Surgery in Canada Enhances Surgical Benefit and Leads to Cost and Comorbidity Reduction

Background: Effective provision of bariatric surgery for patients with obesity may be impeded by concerns of payers regarding costs or perceptions of patients who drop out of surgical programs after referral. Estimates of the cost and comorbidity impact of these inefficiencies in gastric bypass surgery in Canada are lacking but would aid in informing healthcare investment and resource allocation.

Objectives: To estimate total and relative public payer costs for surgery and comorbidities (diabetes, hypertension, and dyslipidemia) in a bariatric surgery population.

Methods: A decision analytic model for a 100-patient cohort in Canada (91% female, mean body mass index 49.2 kg/m², 50% diabetes, 66% hypertension, 59% dyslipidemia). Costs include surgery, surgical complications, and comorbidities over the 10-year post-referral period. Results are calculated as medians and 95% credibility intervals (CrIs) for a pathway with surgery at 1 year (“improved”) compared with surgery at 3.5 years (“standard”). Sensitivity analyses were performed to test independent contributions to results of shorter wait time, better post-surgical weight loss, and randomly sampled cohort demographics.

Results: Compared to standard care, the improved path was associated with reduction in patient-years of treatment for each of the three comorbidities, corresponding to a reduction of $1.1 (0.68–1.6) million, or 34% (26-41%) of total costs. Comorbidity treatment costs were 9.0- and 4.7-fold greater than surgical costs for the standard and improved pathways, respectively. Relative to non-surgical bariatric care, earlier surgery was associated with earlier return on surgical investment and 2-fold reduction in risk of prevalence of each comorbidity compared to delayed surgery.

Conclusions: Comorbidity costs represent a greater burden to payers than the costs of gastric bypass surgery. Investments may be worthwhile to reduce wait times and dropout rates and improve post-surgical weight loss outcomes to save overall costs and reduce patient comorbidity prevalence.

Influence of Sorghum Cultivar, Nitrogen Fertilization, and Insecticides on Infestations of the Sugarcane Aphid (Hemiptera: Aphididae) in the Southern United States

The sugarcane aphid, Melanaphis sacchari Zehntner, is an economically damaging pest of sorghum, Sorghum bicolor (L.), across the southern United States. Field experiments investigated impacts of sorghum cultivar, nitrogen fertilization, and insecticides on M. sacchari infestations and sorghum yields in Louisiana and South Carolina in 2017 and 2018. In South Carolina, M. sacchari densities in unprotected plots peaked on 30-31 July of both years before declining by early- to mid-August. In Louisiana, infestations peaked on 26 and 12 July for 2017 and 2018, respectively, and declined by mid-August. Nitrogen fertilization influenced M. sacchari densities in Louisiana in 2018 with the highest-level infestations recorded from plots that received high N rates. Densities of M. sacchari on susceptible sorghum cultivar, DKS 38-88, were 1.5- to 2.3-fold greater than on DKS 37-07 in both years in Louisiana and in 2018 in South Carolina. Nitrogen fertilization was associated with improved sorghum yields in Louisiana experiments. Sorghum yields across experiments were 2- to 4-fold greater in plots protected with multiple insecticide applications than in unprotected plots. Yield from plots with insecticides sprayed once at currently used action thresholds differed from unprotected plots only in the 2018 Louisiana experiment. Results from these experiments indicate insecticidal protection of susceptible sorghum cultivars remains critical throughout much of the southern United States. Further research is needed to develop integrated management programs that incorporate fertilization manipulation, cultivar resistance, and insecticidal control.

Detailed Characterization of Melanaphis sacchari (Hemiptera: Aphididae) Feeding Behavior on Different Host Plants

Worldwide, Melanaphis sacchari Zehntner is reported on several plants in the family Poaceae, including important crops. In the United States, M. sacchari has been present primarily on sugarcane (Saccharum officinarum L.), but recently sorghum (Sorghum bicolor (L.) Moench) has become a main host. It is not clear how M. sacchari exploits sorghum or other plant species present in the Louisiana agro-ecoscape, but there is potential for these plants to be bridging hosts. Thus, this study determined the feeding behavior of M. sacchari on sorghum, rice, Oryza sativa (L.), sweetpotato, Ipomea batatas (L.), maize, Zea mays (L.), Johnsongrass, S. halepense (L.), and wheat Triticum aestivum (L.) using electrical penetration graphs. Melanaphis sacchari established sustained feeding on sorghum, Johnsongrass, wheat, and rice, only a negligent percentage on maize and no aphid fed on sweetpotato. Differences in Electrical Penetration Graph parameters among the plants in nonpenetrating total time and the lower number of probes, time to penetration initiation, proportion of individuals probing, number of probes shorter than 30 s, number of probes longer than 30 s but shorter than 3 min, pathway phase duration, and number of cell punctures during pathway phase, suggest epidermis and mesophyll factors affecting aphid feeding behavior. While the lack of differences in number of feeding occurrences, total time feeding, and number of sustained feeding occurrences shows that M. sacchari is able to feed on those plants, sieve element factors such as resistance or low nutritional quality prevent the growth of this population in field.

Impact of weight trajectory after bariatric surgery on co-morbidity evolution and burden

Background

Bariatric surgery, such as Roux-en-Y gastric bypass [RYGB] has been shown to be an effective intervention for weight management in select patients. After surgery, different patients respond differently even to the same surgery and have differing weight-change trajectories. The present analysis explores how improving a patient’s post-surgical weight change could impact co-morbidity prevalence, treatment and associated costs in the Canadian setting.

Methods

Published data were used to derive statistical models to predict weight loss and co-morbidity evolution after RYGB. Burden in the form of patient-years of co-morbidity treatment and associated costs was estimated for a 100-patient cohort on one of 6 weight trajectories, and for real-world simulations of mixed patient cohorts where patients experience multiple weight loss outcomes over a 10-year time horizon after RYGB surgery. Costs (2018 Canadian dollars) were considered from the Canadian public payer perspective for diabetes, hypertension and dyslipidaemia. Robustness of results was assessed using probabilistic sensitivity analyses using the R language.

Results

Models fitted to patient data for total weight loss and co-morbidity evolution (resolution and new onset) demonstrated good fitting. Improvement of 100 patients from the worst to the best weight loss trajectory was associated with a 50% reduction in 10-year co-morbidity treatment costs, decreasing to a 27% reduction for an intermediate improvement. Results applied to mixed trajectory cohorts revealed that broad improvements by one trajectory group for all patients were associated with 602, 1710 and 966 patient-years of treatment of type 2 diabetes, hypertension and dyslipidaemia respectively in Ontario, the province of highest RYGB volume, corresponding to a cost difference of $3.9 million.

Conclusions

Post-surgical weight trajectory, even for patients receiving the same surgery, can have a considerable impact on subsequent co-morbidity burden. Given the potential for alleviated burden associated with improving patient trajectory after RYGB, health care systems may wish to consider investments based on local needs and available resources to ensure that more patients achieve a good long-term weight trajectory.

Comparison of Comorbidity Treatment and Costs Associated With Bariatric Surgery Among Adults With Obesity in Canada

IMPORTANCE

Information on the associations between barriers to delivery of bariatric surgery and poor weight trajectory afterward is lacking. Estimates are needed to inform decisions by administrators and clinicians to improve care.

OBJECTIVE

To estimate the difference in patient-years of treatment for diabetes, hypertension, and dyslipidemia and public-payer cost between the Canadian standard and an improved bariatric surgery care pathway.

DESIGN, SETTING, AND PARTICIPANTS

Economic evaluation of a decision analytic model comparing the outcomes of the standard care in Canada with an improved bariatric care pathway with earlier sleeve gastrectomy delivery and better postsurgical weight trajectory. The model was informed by published clinical data (101 studies) and meta-analyses (11 studies) between January and May 2019. Participants were a hypothetical 100-patient cohort with demographic characteristics derived from a Canadian study.

INTERVENTIONS

Reduction of Canadian mean bariatric surgery wait time by 2.5 years following referral and improvement of patient postsurgery weight trajectory to levels observed in other countries.

MAIN OUTCOMES AND MEASURES

Modeling weight trajectory after sleeve gastrectomy and resolution rates for comorbidities in Canada in comparison with an improved care pathway to estimate differences in patient-years of comorbidity treatment over 10 years following referral and the associated costs.

RESULTS

For the 100-patient cohort (mean [SD] 88.2% [1.4%] female; mean [SD] age, 43.6 [9.2] years; mean [SD] body mass index, 49.4 [8.2]; and mean [SD] comorbidity prevalence of 50.0% [4.1%], 66.0% [3.9%], and 59.3% [4.0%] for diabetes, hypertension, and dyslipidemia, respectively) over 10 years following referral, the improved vs standard care pathway was associated with median reduction in patient-years of treatment of 324 (95% credibility interval [CrI], 249-396) for diabetes, 245 (95% CrI, 163-356) for hypertension, and 255 (95% CrI, 169-352) for dyslipidemia, corresponding to total savings of $900 000 (95% CrI, $630 000 to $1.2 million) for public payers in the base case. Relative to standard of care, the associated reduction in costs was approximately 29% (95% CrI, 20%-42%) in the improved pathway. Sensitivity analyses demonstrated independent associations of earlier surgical delivery and various levels of postsurgical weight trajectory improvements with overall savings.

CONCLUSIONS AND RELEVANCE

This study suggests that health care burden may be decreased through improvements to delivery and management of patients undergoing sleeve gastrectomy. More data are needed on long-term patient experience with bariatric surgery in Canada to inform better estimates.

Critical Review of European Health-Economic Guidelines for the Health Technology Assessment of Medical Devices

Background: Health-technology assessment (HTA) is a recognized mechanism to determine the relative benefits of innovative medical technologies. One aspect is their health-economic impact. While the process and methodology for pharmaceuticals is well-established, guidance for medical devices is sparse.

Aim: To provide an overview of the health-economic aspect in current European HTA guidelines concerning medical devices and identifying issues raised and potential improvements proposed in recent literature.

Methodology: Available guidelines by European agencies were each reviewed and summarized. To complement this, a full systematic review of current literature concerning potential improvements to existing HTA practices for medical devices, from PubMed and EMBASE, was conducted; the focus was on health economics. Authors could only review documents in English, French, or German. The systematic review yielded 518 unique articles concerning HTA for medical devices, 32 of which were considered for full-text review after screening of all abstracts.

Results: There is very limited consensus in—and mostly a complete lack of—guidance specific to medical devices in official HTA guidelines, for both clinical and economic analyses. Twenty two of 41 European countries had published official HTA guidance in English, French, or German. Among these only 4 (England, France, the Netherlands, and Sweden) dedicated a chapter or separate document to medical devices. In the literature, there is sufficient evidence to suggest medical devices need to be addressed separately from pharmaceuticals. However, mostly challenges are discussed rather than implementable solutions offered. We present the following set of frequently discussed issues and summarize any solutions that pertain to them: a weak evidence base, learning-curve effects, organizational impact, incremental innovation, diversity of devices, dynamic pricing, and transferability. We further combine reviewed information to suggest a set of possible best practices for health-economic assessment of medical devices.

Conclusion: For greater efficiency in medical-device innovation, European agencies should look to (re-)address the specific requirements of medical devices in their HTA guidelines. When both the health-economic and data requirements for the HTA of medical devices are defined, the development of practical solutions will likely follow.

Brake response time after modern total knee arthroplasty: How soon can patients drive?

BACKGROUND

Recent advances in the performance of total knee arthroplasty may allow for return to driving sooner than the current recommendation of six to eight weeks. The purpose of this study was to evaluate at what time point patients may safely return to driving after modern total knee arthroplasty.

METHODS

Thirty-two consecutive patients underwent pre-operative and weekly post-operative assessments of brake reaction time before and for eight weeks after undergoing total knee arthroplasty.

RESULTS

Overall, patients returned to their preoperative baseline brake reaction times by the second postoperative week. There was a significant difference in regard to gender but not laterality or age. Specifically, men achieved preoperative brake reaction times by the first postoperative week and women by the second.

CONCLUSIONS

Patients undergoing total knee arthroplasty with a modern perioperative pathway appear to achieve preoperative brake reaction times by the second postoperative week when not taking narcotic pain medication. However, the safe return to driving in each patient must be approached individually. Surgeon discretion to release a patient to drive is always prudent and the decision should be considered on an individual basis.

Freiburg RNA tools: a central online resource for RNA-focused research and teaching

The Freiburg RNA tools webserver is a well established online resource for RNA-focused research. It provides a unified user interface and comprehensive result visualization for efficient command line tools. The webserver includes RNA-RNA interaction prediction (IntaRNA, CopraRNA, metaMIR), sRNA homology search (GLASSgo), sequence-structure alignments (LocARNA, MARNA, CARNA, ExpaRNA), CRISPR repeat classification (CRISPRmap), sequence design (antaRNA, INFO-RNA, SECISDesign), structure aberration evaluation of point mutations (RaSE), and RNA/protein-family models visualization (CMV), and other methods. Open education resources offer interactive visualizations of RNA structure and RNA-RNA interaction prediction as well as basic and advanced sequence alignment algorithms. The services are freely available at http://rna.informatik.uni-freiburg.de.

Clinical and economic burden of procedural sedation-related adverse events and their outcomes: analysis from five countries

Background

Studies have reported on the incidence of sedation-related adverse events (AEs), but little is known about their impact on health care costs and resource use.

Methods

Health care providers and payers in five countries were recruited for an online survey by independent administrators to ensure that investigators and respondents were blinded to each other. Surveys were conducted in the local language and began with a “screener” to ensure that respondents had relevant expertise and experience. Responses were analyzed using Excel and R, with the Dixon’s Q statistic used to identify and remove outliers. Global and country-specific average treatment patterns were calculated via bootstrapping; costs were mean values. The sum product of costs and intervention probability gave a cost per AE.

Results

Responses were received from 101 providers and 26 payers, the majority having >5 years of experience. At a minimum, the respondents performed a total of 3,430 procedural sedations per month. All AEs detailed occurred in clinical practice in the last year and were reported to cause procedural delays and cancellations in some patients. Standard procedural sedation costs ranged from €74 (Germany) to $2,300 (US). Respondents estimated that AEs would increase costs by between 16% (Italy) and 179% (US). Hypotension was reported as the most commonly observed AE with an associated global mean cost (interquartile range) of $43 ($27–$68). Other frequent AEs, including mild hypotension, bradycardia, tachycardia, mild oxygen desaturation, hypertension, and brief apnea, were estimated to increase health care spending on procedural sedation by $2.2 billion annually in the US.

Conclusion

All sedation-related AEs can increase health care costs and result in substantial delays or cancellations of subsequent procedures. The prevention of even minor AEs during procedural sedation may be crucial to ensuring its value as a health care service.

Combinatorial ensemble miRNA target prediction of co-regulation networks with non-prediction data

MicroRNAs (miRNAs) are key regulators of cell-fate decisions in development and disease with a vast array of target interactions that can be investigated using computational approaches. For this study, we developed metaMIR, a combinatorial approach to identify miRNAs that co-regulate identified subsets of genes from a user-supplied list. We based metaMIR predictions on an improved dataset of human miRNA–target interactions, compiled using a machine-learning-based meta-analysis of established algorithms. Simultaneously, the inverse dataset of negative interactions not likely to occur was extracted to increase classifier performance, as measured using an expansive set of experimentally validated interactions from a variety of sources. In a second differential mode, candidate miRNAs are predicted by indicating genes to be targeted and others to be avoided to potentially increase specificity of results. As an example, we investigate the neural crest, a transient structure in vertebrate development where miRNAs play a pivotal role. Patterns of metaMIR-predicted miRNA regulation alone partially recapitulated functional relationships among genes, and separate differential analysis revealed miRNA candidates that would downregulate components implicated in cancer progression while not targeting tumour suppressors. Such an approach could aid in therapeutic application of miRNAs to reduce unintended effects. The utility is available at http://rna.informatik.uni-freiburg.de/metaMIR/.

Influence of Host Quality and Temperature on the Biology of Diaeretiella rapae (Hymenoptera: Braconidae, Aphidiinae)

Biological features of Diaeretiella rapae (McIntosh), an aphid parasitoid, are conditioned by temperature and host. However, studies of host quality changes due to temperature adaptability have not been performed previously. Therefore, this study evaluated the adaptability of Lipaphis pseudobrassicae (Davis) and Myzus persicae (Sulzer) to high temperature, high temperature effect on their quality as hosts for D. rapae, and on parasitoid's thermal threshold. Aphid development, survivorship, fecundity, and longevity were compared at 19 °C and 28 °C. Host quality in different temperatures was determined through evaluation of parasitoid biology. Thermal threshold of D. rapae was determined using development time data. At 28 °C, development time, rate of immature survival, and total fecundity rates were greater in L. pseudobrassicae than in M. persicae. Development time of D. rapae in L. pseudobrassicae was shorter than that in M. persicae at 28 °C and 31 °C for females and at 31 °C for males. The thermal threshold of D. rapae was 6.38 °C and 3.33 °C for females and 4.45 °C and 3.63 °C for males developed on L. pseudobrassicae and M. persicae, respectively. Diaeretiella rapae size gain was greater in L. pseudobrassicae than that in M. persicae at 25 °C and 28 °C. Lipaphis pseudobrassicae showed better adaptation than M. persicae to elevated temperatures, which resulted in a better quality host for D. rapae at temperatures of 28 °C and 31 °C and a higher lower thermal threshold when the parasitoid developed within L. pseudobrassicae. The host's adaptation to high temperatures is a determinant of host quality for the parasitoid at that same climatic condition.

Hg concentrations in fish from coastal waters of California and Western North America

The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3μg/gwet weight (ww), and 10 locations an average above 1.0μg/gww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on Hg and other contaminants in coastal fish. An assessment of the raw data from these databases suggested the presence of relatively high concentrations along the California coast and in Puget Sound, and relatively low concentrations along the coasts of Alaska and Oregon, and the outer coast of Washington. The dataset suggests that Hg concentrations of public health concern can be observed at any location on the coast of Western North America where long-lived predator species are sampled. Output from a linear mixed-effects model resembled the spatial pattern observed for the raw data and suggested, based on the limited dataset, a lack of trend in fish Hg over the nearly 30-year period covered by the dataset. Expanded and continued monitoring, accompanied by rigorous data management procedures, would be of great value in characterizing methylHg exposure, and tracking changes in contamination of coastal fish in response to possible increases in atmospheric Hg emissions in Asia, climate change, and terrestrial Hg control efforts in coastal watersheds.

Treatment of Infected Forearm Nonunions With Large Complete Segmental Defects Using Bulk Allograft and Intramedullary Fixation

PURPOSE

The purpose of this study is to report the results of a series of infected forearm nonunions treated from 1998 to 2012 using a staged reconstruction technique.

METHODS

At a median of 42 months follow-up, 7 patients who had an average segmental defect of 4.9 cm (range, 2.3-10.4 cm) were available for clinical and radiographic evaluation. Treatment consisted of serial debridement, implantation of an antibiotic cement spacer, and staged reconstruction using a bulk radius or ulna allograft with intramedullary fixation.

RESULTS

All 7 patients ultimately achieved solid bone union, although 4 patients (57%) required additional surgery, consisting of autologous bone grafting and plating, to achieve healing at 1 of the allograft-host junction sites. No patient had recurrence of infection, and all reported substantial improvement with increased function and decreased pain.

CONCLUSIONS

Our approach ultimately resulted in a 100% union rate without recurrence of infection, although many patients may require additional surgery to attain healing at both allograft-junction sites. Using bulk allograft provides the ability to span a large defect while reconstituting the forearm anatomy.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Partial Life History of Chrysodeixis includens (Lepidoptera: Noctuidae) on Summer Hosts

The soybean looper, Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae), is a major defoliating pest of soybeans, Glycine max (L.) Merrill, in Louisiana. However, other alternate host crops in the agroecosystem have the potential to impact C. includens populations. Life table statistics of C. includens on four host plants were evaluated. C. includens larvae were fed leaves of three cotton Gossypium hirsutum L. cultivars 'DP 143 B2RF,' 'DP 174 RF,' and 'PHY 485 WRF'; cowpea Vigna unguiculata (L.) Walpers 'California Blackeye'; three soybean cultivars 'Lyon,' 'PI 227687,' and 'RC 4955'; and sweetpotato Ipomoea batatas (L.) Lamarck 'Evangeline.' All C. includens larvae reared on cotton cultivars DP 143 B2RF and PHY 485 WRF experienced 100% mortality during the first instar. Total developmental period of preadult C. includens was significantly shorter on cotton DP 174 RF and cowpea California Blackeye but longer on sweetpotato Evangeline. Sweetpotato Evangeline had the highest amount of leaf tissue consumed and soybean Lyon had the least. Pupal weight was highest when insects fed on cotton DP 174 RF and lowest on soybean PI 227687. Life table statistics showed that the highest intrinsic rate of increase and net reproductive rate were attained when insects were reared on cotton DP 174 RF and cowpea California Blackeye whilst the lowest were recorded on soybean PI 227687. This study provides valuable information on the role of alternative host crops on the partial life history of C. includens in Louisiana agroecosystems.

Does Postoperative Radiation Decrease Heterotopic Ossification After the Kocher-Langenbeck Approach for Acetabular Fracture?

BACKGROUND

Controversy regarding heterotopic ossification (HO) prophylaxis exists after Kocher-Langenbeck for treatment of acetabular fracture. Prophylaxis options include antiinflammatory oral medications, single-dose radiation therapy, and débridement of gluteus minimus muscle. Prior literature has suggested single-dose radiation therapy as the best prophylaxis to prevent HO formation. However, recent reports have emerged of radiation-induced sarcoma after radiotherapy for HO prophylaxis, which has led many surgeons to reconsider the risks and benefits of single-dose radiation therapy. We set out to determine if radiotherapy, in addition to standard débridement of gluteus minimus muscle, affected postoperative HO formation after a Kocher-Langenbeck approach for acetabular fracture.

QUESTIONS/PURPOSES

(1) After the Kocher-Langenbeck approach and gluteus minimus débridement, is single-dose radiotherapy associated with a decreased risk of HO? (2) Does addition of single-dose radiotherapy prolong length of stay after a Kocher-Langenbeck approach and gluteus minimus débridement as compared with patients without radiotherapy?

METHODS

After institutional review board approval, all adult patients treated for acetabular fracture by a single surgeon with a Kocher-Langenbeck approach between August 2011 and October 2014 were identified (n = 60). Débridement of gluteus minimus muscle caudal to the superior gluteal bundle was standard in all patients. Radiotherapy was given with a single dose of 700 cGy within 72 hours of surgery from August 2011 until April 2013. Patients treated subsequently did not receive radiotherapy. Patients treated with indomethacin (n = 1) and with fewer than 10 weeks followup were excluded (n = 12) because several studies suggest that most HO that develops is visible by that point in time. Our study group totaled 46 patients with 24 in the radiotherapy and débridement group and 22 in the débridement group. Charts were reviewed to determine length of stay. Attending orthopaedic trauma surgeons who were blinded to the patient's treatment group graded all followup radiographs according to the Brooker system, and Classes III and IV HO were considered clinically important Fisher's exact test was used to analyze clinically significant differences HO between the two groups. Length of stay was compared using a t-test.

RESULTS

Single-dose radiotherapy is associated with a decreased risk of clinically important (Brooker III-IV) HO after a Kocher-Langenbeck approach and gluteus minimus débridement (radiotherapy: one of 24 [4%], no radiotherapy: seven of 22 [32%], relative risk: 0.131 [95% confidence interval {CI}, 0.018-0.981], p = 0.020). Addition of single-dose radiotherapy did not result in increased length of stay (radiotherapy: 12 ± 7.0 days; no radiotherapy: 11 ± 7.2 days; mean difference: 1.0 [95% CI, -3.2 to 5.2] days, p = 0.635).

CONCLUSIONS

Single-dose radiation in combination with gluteus minimus débridement decreases the risk of clinically important HO compared with gluteus minimus débridement alone after a Kocher-Langenbeck approach for acetabular fracture. No differences in length of stay were seen. Surgeons who chose not to use radiotherapy as a result of concern for future sarcoma may see higher rates of clinically significant HO after a Kocher-Langenbeck approach for acetabular fracture fixation.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The Hippo pathway member YAP enhances human neural crest cell fate and migration

The Hippo/YAP pathway serves as a major integrator of cell surface-mediated signals and regulates key processes during development and tumorigenesis. The neural crest is an embryonic tissue known to respond to multiple environmental cues in order to acquire appropriate cell fate and migration properties. Using multiple in vitro models of human neural development (pluripotent stem cell-derived neural stem cells; LUHMES, NTERA2 and SH-SY5Y cell lines), we investigated the role of Hippo/YAP signaling in neural differentiation and neural crest development. We report that the activity of YAP promotes an early neural crest phenotype and migration, and provide the first evidence for an interaction between Hippo/YAP and retinoic acid signaling in this system.

Trends and Patterns in Reporting of Patient Safety Situations in Transplantation

Analysis and dissemination of transplant patient safety data are essential to understanding key issues facing the transplant community and fostering a "culture of safety." The Organ Procurement and Transplantation Network's (OPTN) Operations and Safety Committee de-identified safety situations reported through several mechanisms, including the OPTN's online patient safety portal, through which the number of reported cases has risen sharply. From 2012 to 2013, 438 events were received through either the online portal or other reporting pathways, and about half were self-reports. Communication breakdowns (22.8%) and testing issues (16.0%) were the most common types. Events included preventable errors that led to organ discard as well as near misses. Among events reported by Organ Procurement Organization (OPOs), half came from just 10 of the 58 institutions, while half of events reported by transplant centers came from just 21 of 250 institutions. Thirteen (23%) OPOs and 155 (62%) transplant centers reported no events, suggesting substantial underreporting of safety-related errors to the national database. This is the first comprehensive, published report of the OPTN's safety efforts. Our goals are to raise awareness of safety data recently reported to the OPTN, encourage additional reporting, and spur systems improvements to mitigate future risk.

Inhibitor recurrence after immune tolerance induction: a multicenter retrospective cohort study

BACKGROUND

Immune tolerance induction (ITI) in patients with congenital hemophilia A is successful in up to 70%. Although there is growing understanding of predictors of response to ITI, the probability and predictors of inhibitor recurrence after successful ITI are not well understood.

OBJECTIVES

To determine the association of clinical characteristics, particularly adherence to factor VIII (FVIII) prophylaxis after ITI, with inhibitor recurrence in patients with hemophilia A who were considered tolerant after ITI.

METHODS

In this multicenter retrospective cohort study, 64 subjects with FVIII level < 2% who were considered successfully tolerant after ITI were analyzed to estimate the cumulative probability of inhibitor recurrence using the Kaplan-Meier method. The association of clinical characteristics with inhibitor recurrence was assessed using logistic regression.

RESULTS

A recurrent inhibitor titer ≥ 0.6 BU mL(-1) occurred at least once in 19 (29.7%) and more than once in 12 (18.8%). The probability of any recurrent inhibitor at 1 and 5 years was 12.8% and 32.5%, respectively. Having a recurrent inhibitor was associated with having received immune modulation during ITI (odds ratio [OR] 3.8, 95% confidence interval [CI] 1.2-22.4) and FVIII recovery of < 85% at the end of ITI (OR 2.6, 95% CI 1.3-5.9) but was not associated with adherence to post-ITI prophylactic FVIII infusion (OR 0.5, 95% CI 0.06-4.3).

CONCLUSIONS

The use of immune modulation therapy during ITI and lower FVIII recovery at the end of ITI appear to be associated with an increased risk of inhibitor recurrence after successful ITI. Adherence to post-ITI prophylactic FVIII infusions is not a major determinant of recurrence.

Postoperative Coronal Alignment After Total Knee Arthroplasty: Does Tailoring the Femoral Valgus Cut Angle Really Matter?

Postoperative alignment was measured in 80 TKA divided into 2 groups. Knees in the tailored group (n=40) were performed with a personalized valgus cut angle (VCA) based on preoperative hip-to-ankle (HTA) radiographs. The fixed group knees (n=40) were performed utilizing a 4° VCA in valgus knees and obese patients, and 5° in neutral and varus knees. There was no significant difference between groups in average preoperative mechanical alignment or average severity of preoperative deformity. There was no statistically significant difference between groups in postoperative mechanical alignment (tailored: 2.6°; fixed: 1.3°; P=0.08) or severity of residual deformity (tailored: 3.5°; fixed: 2.6°; P=0.10). Accuracy of the tibial cut angle (TCA) and severity of the preoperative deformity were strong independent predictors of postoperative alignment (R(2)=58% and R(2)=33%, respectively).

Diversity of Plasmids and Antimicrobial Resistance Genes in Multidrug-Resistant Escherichia coli Isolated from Healthy Companion Animals

The presence and transfer of antimicrobial resistance genes from commensal bacteria in companion animals to more pathogenic bacteria may contribute to dissemination of antimicrobial resistance. The purpose of this study was to determine antimicrobial resistance gene content and the presence of genetic elements in antimicrobial resistant Escherichia coli from healthy companion animals. In our previous study, from May to August, 2007, healthy companion animals (155 dogs and 121 cats) from three veterinary clinics in the Athens, GA, USA area were sampled and multidrug-resistant E. coli (n = 36; MDR, resistance to ≥ 2 antimicrobial classes) were obtained. Of the 25 different plasmid replicon types tested by PCR, at least one plasmid replicon type was detected in 94% (34/36) of the MDR E. coli; four isolates contained as many as five different plasmid replicons. Nine replicon types (FIA, FIB, FII, I2, A/C, U, P, I1 and HI2) were identified with FIB, FII, I2 as the most common pattern. The presence of class I integrons (intI) was detected in 61% (22/36) of the isolates with eight isolates containing aminoglycoside- and/or trimethoprim-resistance genes in the variable cassette region of intI. Microarray analysis of a subset of the MDR E. coli (n = 9) identified the presence of genes conferring resistance to aminoglycosides (aac, aad, aph and strA/B), β-lactams (ampC, cmy, tem and vim), chloramphenicol (cat), sulfonamides (sulI and sulII), tetracycline [tet(A), tet(B), tet(C), tet(D) and regulator, tetR] and trimethoprim (dfrA). Antimicrobial resistance to eight antimicrobials (ampicillin, cefoxitin, ceftiofur, amoxicillin/clavulanic acid, streptomycin, gentamicin, sulfisoxazole and trimethoprim-sulfamethoxazole) and five plasmid replicons (FIA, FIB, FII, I1 and I2) were transferred via conjugation. The presence of antimicrobial resistance genes, intI and transferable plasmid replicons indicate that E. coli from companion animals may play an important role in the dissemination of antimicrobial resistance, particularly to human hosts during contact.

Field evaluation of the response of Aedes albopictus (Stegomyia albopicta) to three oviposition attractants and different ovitrap placements using black and clear autocidal ovitraps in a rural area of Same, Timor-Leste

Known oviposition attractants or stimulants were compared, singly and in combination, using inexpensive autocidal ovitraps designed to trap emerging adults, in a rural area of Timor-Leste during the dry season. In this area, the dengue vector Aedes albopictus (Stegomyia albopicta) Skuse (Diptera: Culicidae) was abundant, but Aedes aegypti (Stegomyia aegypti) L. was not detected. The attractants were: (a) a compound found in Aedes eggs (dodecanoic acid); (b) components of nitrogen, phosphorous and potassium-based (NPK) fertilizer, and (c) infusions of discarded cigarette butts. A solution of ammonium phosphate and potassium nitrate was significantly more attractive to gravid Ae. albopictus than water only. Dodecanoic acid and cigarette butt infusions were not significantly more attractive than the control; however, they attracted various other Diptera and many non-culicid larvae developed in ovitraps in which these substances were used; thus, the presence of eggs or larvae of other species may have deterred Aedes oviposition. Significantly more Aedes eggs were found in ovitraps under vegetation than in ovitraps placed inside houses or against external walls. Clear-sided ovitraps in which black mesh was placed over a black ring floating on the water surface collected significantly fewer eggs than black ovitraps with identically placed mesh and rings.

Carriage of methicillin-resistant staphylococci by healthy companion animals in the US

Antimicrobial-resistant staphylococci have been associated with wounded or ill companion animals, but little is known about the prevalence of resistant staphylococci among healthy animals. In this study, 276 healthy dogs and cats from veterinary clinics were tested for the presence of antimicrobial-resistant Staphylococcus spp. Isolates were tested for antimicrobial susceptibility and the presence of select resistance genes, and typed using Pulsed-Field Gel Electrophoresis (PFGE). Staphylococcus aureus and Staphylococcus pseudintermedius were also characterized using multilocus sequence typing (MLST), spa typing and SCCmec typing. Approximately 5% (14/276) of the animals were positive by enrichment for five species of staphylococci [Staph. aureus (n = 11), Staph. pseudintermedius (n = 4), Staphylococcus sciuri (n = 6), Staphylococcus simulans (n = 1) and Staphylococcus warneri (n = 1)]. Seventy-eight per cent (18/23) of staphylococci were resistant to oxacillin and also multidrug resistant (resistance to ≥ 2 antimicrobials). All Staph. aureus isolates were mecA+ and blaZ+, SCCmec type II, spa type t002, ST5 and clonal using PFGE. Staphylococcus pseudintermedius were SCCmec type IV or V, spa type t06 and ST170; two of the isolates were pvl(+) . These results suggest that healthy companion animals may be a reservoir of multidrug-resistant staphylococci, which may be transferred to owners and others who handle companion animals.

SIGNIFICANCE AND IMPACT OF THE STUDY

In this study, antimicrobial-resistant coagulase-negative and coagulase-positive staphylococci were isolated from various body sites on healthy dogs and cats. Resistance to 14 antimicrobials was observed including resistance to oxacillin; the majority of staphylococci were also multidrug resistant. Results from this study suggest that healthy dogs and cats may act as reservoirs of antimicrobial-resistant bacteria that may be transferred to people by simple interaction with the animals. Such carriage poses an underlying risk of infection, which should be considered during handling of healthy dogs and cats by pet owners and veterinary personnel.

Stylet penetration behaviors of Myzus persicae (Hemiptera: Aphididae) on four Ipomoea spp. infected or noninfected with sweet potato potyviruses

Myzus persicae (Sulzer) is an efficient vector of potyviruses in sweet potato, Ipomoea batatas (L.). These potyviruses also infect members of the morning glory family Ipomoea cordatotriloba Dennstedt and Ipomoea hederacea Jacqin commonly found within or around sweet potato fields. Infection of sweet potato with potyviruses increases the intrinsic rate of increase of M. persicae. Thus, from the epidemiological stand point, virus infection can modify vector population dynamics, and therefore increase virus spread. To better understand this, stylet penetration behaviors of M. persicae on virus infected and noninfected sweet potato cvs. 'Beauregard' and 'Evangeline', as well as morning glory plants I. cordatotriloba and I. hederacea were monitored. Stylet penetration behaviors associated with nonpersistent virus transmission such as time to first intracellular puncture (potential drop), number of potential drops, duration of potential drop, duration of potential drop subphase II-3, and number of potential drops with subphase II-3 pulses were significantly increased on virus-infected compared with noninfected Beauregard, but greatly reduced on virus-infected compared with noninfected I. hederacea plants. Stylet penetration behaviors associated with host acceptance such as reduced nonprobing duration and nonprobing events were greater on virus-infected compared with noninfected Beauregard plants. In contrast, on Evangeline, I. cordatotriloba and I. hederacea stylet penetration behaviors by M. persicae indicate it had less preference for virus-infected compared with noninfected plants.

Disentangling Electronic and Vibrational Coherence in the Phycocyanin-645 Light-Harvesting Complex

Energy transfer between chromophores in photosynthesis proceeds with near-unity quantum efficiency. Understanding the precise mechanisms of these processes is made difficult by the complexity of the electronic structure and interactions with different vibrational modes. Two-dimensional spectroscopy has helped resolve some of the ambiguities and identified quantum effects that may be important for highly efficient energy transfer. Many questions remain, however, including whether the coherences observed are electronic and/or vibrational in nature and what role they play. We utilize a two-color, four-wave mixing experiment with control of the wavelength and polarization to selectively excite specific coherence pathways. For the light-harvesting complex PC645, from cryptophyte algae, we reveal and identify specific contributions from both electronic and vibrational coherences and determine an excited-state structure based on two strongly coupled electronic states and two vibrational modes. Separation of the coherence pathways also uncovers the complex evolution of these coherences and the states involved.

High-order harmonic generation from a dual-gas, multi-jet array with individual gas jet control

We present a gas jet array for use in high-order harmonic generation experiments. Precise control of the pressure in each individual gas jet has allowed a thorough investigation into mechanisms contributing to the selective enhancement observed in the harmonic spectra produced by dual-gas, multi-jet arrays. Our results reveal that in our case, the dominant enhancement mechanism is the result of a compression of the harmonic-producing gas jet due to the presence of other gas jets in the array. The individual control of the gas jets in the array also provides a promising method for enhancing the harmonic yield by precise tailoring of the length and pressure gradient of the interaction region.

Population dynamics of three aphid species (Hemiptera: Aphididae) on four Ipomoea spp. infected or noninfected with sweetpotato potyviruses

Three aphid species, Aphis gossypii Glover and Myzus persicae (Sulzer) (efficient sweetpotato potyvirus vectors) and Rhopalosiphum padi (L.) (an inefficient vector), are commonly found in sweet potato, Ipomoea batatas (L.), in Louisiana. Field-grown sweet potatoes are naturally infected with several potyviruses: Sweet potato feathery mottle virus, Sweet potato virus G, and Sweet potato virus 2. Thus, these aphids commonly encounter virus-infected hosts. What is not known is how each of these aphids responds to sweet potato, either infected or virus-free. The objectives of this study were to 1) determine if these aphid species can colonize mixed virus-infected sweet potato 'Beauregard', and if so, 2) determine the effects of virus infection on the population dynamics of each aphid. A. gossypii failed to larviposit and R. padi deposited a single nymph that died within a day on mixed virus-infected Beauregard. M. persicae larviposited and colonized Beauregard and further life-table analyses were warranted. M. persicae had a significantly greater reproduction on sweet potato cultivars Beauregard and 'Evangeline' with mixed virus infection compared with noninfected plants. On morning glory species, Ipomoea cordatotriloba (Dennestedt) and Ipomoea hederacea (Jacquin), M. persicae had a significantly lower reproduction on Sweet potato feathery mottle virus-infected compared with noninfected plants.

Species composition and seasonal abundance of stink bugs (Hemiptera: Pentatomidae) in Louisiana soybean

In Louisiana during the last decade, the redbanded stink bug, Piezodorus guildinii (Westwood), has become a significant and yield-limiting pest of soybean. The redbanded stink bug was previously reported in the United States in 1892, but was never considered an economically important pest until recently. Soybeans representing four maturity groups (MG) III, IV, V, and VI were sampled weekly from beginning bloom (R1) to physiological maturity (R8) during 2008-2010 at five locations across Louisiana to determine the Pentatomidae composition. In total, 13,146 stink bugs were captured and subsequently identified to species. The predominant species included the redbanded stink bug (54.2%); southern green stink bug (27.1%), Nezara viridula L.; brown stink bug (6.6%), Euschistus servus (Say); and green stink bug (5.5%), Acrosternum hilare (Say). Redbanded stink bug comprised the largest percentage of the complex collected at four of the five survey sites. Numbers exceeding action thresholds of this stink bug complex were only detected during R4 to R7 growth stages. Redbanded stink bug accounted for the largest percentage of the stink bug complex in early maturing soybean varieties (MG III [86%] and IV [60%]) and declined in later maturing soybeans (MG V [54%] and VI [50%]). The redbanded stink bug was initially identified in southern Louisiana during 2000 and had been reported in all soybean producing regions in Louisiana by 2006. This survey is the first to report the redbanded stink bug as a predominant pest of soybeans from locations within the United States.

Combined flow cytometric analysis of surface and intracellular antigens reveals surface molecule markers of human neuropoiesis

Surface molecule profiles undergo dynamic changes in physiology and pathology, serve as markers of cellular state and phenotype and can be exploited for cell selection strategies and diagnostics. The isolation of well-defined cell subsets is needed for in vivo and in vitro applications in stem cell biology. In this technical report, we present an approach for defining a subset of interest in a mixed cell population by flow cytometric detection of intracellular antigens. We have developed a fully validated protocol that enables the co-detection of cluster of differentiation (CD) surface antigens on fixed, permeabilized neural cell populations defined by intracellular staining. Determining the degree of co-expression of surface marker candidates with intracellular target population markers (nestin, MAP2, doublecortin, TUJ1) on neuroblastoma cell lines (SH-SY5Y, BE(2)-M17) yielded a combinatorial CD49f^-/CD200^high surface marker panel. Its application in fluorescence-activated cell sorting (FACS) generated enriched neuronal cultures from differentiated cell suspensions derived from human induced pluripotent stem cells. Our data underlines the feasibility of using the described co-labeling protocol and co-expression analysis for quantitative assays in mammalian neurobiology and for screening approaches to identify much needed surface markers in stem cell biology.

The Role of Aphid Abundance, Species Diversity, and Virus Titer in the Spread of Sweetpotato Potyviruses in Louisiana and Mississippi

Sweet potato feathery mottle virus (SPFMV), Sweet potato virus G (SPVG), and Sweet potato virus 2 (SPV2) are sweetpotato (Ipomoea batatas) potyviruses nonpersistently transmitted by aphids. Our objective was to determine how aphid abundance, aphid species diversity, and virus titers relate to the spread of SPFMV, SPVG, and SPV2 in Louisiana and Mississippi sweetpotato fields. The most abundant aphid species were Aphis gossypii, Myzus persicae, Rhopalosiphum padi, and Therioaphis trifolii. Aphids were captured during the entire crop cycle but virus infection of sentinel plants occurred mainly during the months of June to August. SPFMV was more commonly detected than SPVG or SPV2 in sentinel plants. Virus titers for SPFMV were higher in samples beginning in late June. Because significant aphid populations were present during April to June when virus titers were low in sweetpotato and there was very little virus infection of sentinel plants, low virus titers may have limited aphid acquisition and transmission opportunities. This is the first study to comprehensively examine aphid transmission of potyviruses in sweetpotato crops in the United States and includes the first report of R. maidis and R. padi as vectors of SPFMV, though they were less efficient than A. gossypii or M. persicae.

Reducing methylmercury accumulation in the food webs of San Francisco Bay and its local watersheds

San Francisco Bay (California, USA) and its local watersheds present an interesting case study in estuarine mercury (Hg) contamination. This review focuses on the most promising avenues for attempting to reduce methylmercury (MeHg) contamination in Bay Area aquatic food webs and identifying the scientific information that is most urgently needed to support these efforts. Concern for human exposure to MeHg in the region has led to advisories for consumption of sport fish. Striped bass from the Bay have the highest average Hg concentration measured for this species in USA estuaries, and this degree of contamination has been constant for the past 40 years. Similarly, largemouth bass in some Bay Area reservoirs have some of the highest Hg concentrations observed in the entire US. Bay Area wildlife, particularly birds, face potential impacts to reproduction based on Hg concentrations in the tissues of several Bay species. Source control of Hg is one of the primary possible approaches for reducing MeHg accumulation in Bay Area aquatic food webs. Recent findings (particularly Hg isotope measurements) indicate that the decades-long residence time of particle-associated Hg in the Bay is sufficient to allow significant conversion of even the insoluble forms of Hg into MeHg. Past inputs have been thoroughly mixed throughout this shallow and dynamic estuary. The large pool of Hg already present in the ecosystem dominates the fraction converted to MeHg and accumulating in the food web. Consequently, decreasing external Hg inputs can be expected to reduce MeHg in the food web, but it will likely take many decades to centuries before those reductions are achieved. Extensive efforts to reduce loads from the largest Hg mining source (the historic New Almaden mining district) are underway. Hg is spread widely across the urban landscape, but there are a number of key sources, source areas, and pathways that provide opportunities to capture larger quantities of Hg and reduce loads from urban runoff. Atmospheric deposition is a lower priority for source control in the Bay Area due to a combination of a lack of major local sources. Internal net production of MeHg is the dominant source of MeHg that enters the food web. Controlling internal net production is the second primary management approach, and has the potential to reduce food web MeHg in some habitats more effectively and within a much shorter time-frame. Controlling net MeHg production and accumulation in the food web of upstream reservoirs and ponds is very promising due to the many features of these ecosystems that can be manipulated. The most feasible control options in tidal marshes relate to the design of flow patterns and subhabitats in restoration projects. Options for controlling MeHg production in open Bay habitat are limited due primarily to the highly dispersed distribution of Hg throughout the ecosystem. Other changes in these habitats may also have a large influence on food web MeHg, including temperature changes due to global warming, sea level rise, food web alterations due to introduced species and other causes, and changes in sediment supply. Other options for reducing or mitigating exposure and risk include controlling bioaccumulation, cleanup of contaminated sites, and reducing other factors (e.g., habitat availability) that limit at-risk wildlife populations.

Effect of Host Plant, Aphid Species, and Virus Infection Status on Transmission of Sweetpotato feathery mottle virus

Sweetpotato feathery mottle virus (SPFMV) is a nonpersistently transmitted virus known to infect sweetpotato (Ipomoea batatas) and wild morning glory plants. SPFMV is vectored by various aphid species, among them the green peach aphid, Myzus persicae, and the cotton aphid, Aphis gossypii. Our objective was to determine whether differences in acquisition hosts (sweetpotato and morning glory), aphid species (M. persicae and A. gossypii), and infection status (single versus mixed infection) influenced transmission of SPFMV. SPFMV transmission from I. hederacea with a natural mixed infection by A. gossypii (39%) was significantly greater than in other host-virus combinations. Successful transmissions by A. gossypii were significantly greater compared with M. persicae in all host-virus combinations. Virus titers in source leaves were significantly greater in single- and mixed-infected I. hederacea and single-infected I. cordatotriloba compared with other host-virus combinations. There was a significant positive correlation between virus titer and transmission by both aphid species. These results suggest that, under controlled conditions, SPFMV is more readily transmitted from infected morning glory plants than from sweetpotato. Additionally, mixed-infected plants are better virus sources for transmission than single-infected, and A. gossypii is a more efficient vector than M. persicae under laboratory conditions.

Serum IL-17F does not predict poor response to IM IFNβ-1a in relapsing-remitting MS

OBJECTIVE

There is a significant unmet need for serum biomarkers in relapsing-remitting multiple sclerosis (RRMS) that are predictive of therapeutic response to disease-modifying therapies. Following a recent Stanford study which reported that pretreatment levels of serum interleukin (IL)-17F could predict poor response to interferon-β (IFNβ) therapy, we sought to validate the finding using samples from a large clinical trial.

METHODS

The validation cohort included 54 good responders (GR) and 64 poor responders (PR) selected from 762 subjects with RRMS from the IM IFNβ-1a dose comparison study (Avonex study C94-805). Subjects were classified as GR and PR based on the number of relapses, Expanded Disability Status Scale score, and new and enlarging T2 lesions on MRI. Serum samples were assayed for IL-17F using a multiplexed Luminex assay and for IL-17F/F using an ELISA. Replicate aliquots from the Stanford study were also assayed to assure reproducibility of methods.

RESULTS

Median pretreatment and post-treatment serum IL-17F levels were not statistically significantly different between GR and PR, and serum IL-7/IL-17F ratios were also not predictive of response status. Replicate aliquots from the Stanford study showed good correlation to their original cohort (r = 0.77).

CONCLUSIONS

We were unable to validate the finding that serum IL-17F is a predictor of PR in a large independent cohort of subjects with RRMS. Differences in patient populations and methodology might explain the failure to validate the results from the Stanford study.