Evaluation of two fibrous wound dressings for the management of leg ulcers: results of a European randomised controlled trial (EARTH RCT).

OBJECTIVE: To evaluate the performance (efficacy, safety and acceptability) of a new micro-adherent absorbent dressing (UrgoClean®) compared with a hydrofiber dressing (Aquacel®) in the local management of venous leg ulcers, in the debridement stage. METHOD: A non-inferiority European randomised controlled clinical trial (RCT) was conducted in 37 centres, on patients presenting with venous or predominantly venous, mixed aetiology leg ulcers at their sloughy stage (with more than 70% of the wound bed covered with slough at baseline). Patients were followed over a 6-week period and assessed weekly. The primary judgement criteria was the relative regression of the wound surface area after the 6-week treatment period. Secondary endpoints were the relative reduction of sloughy tissue and the percentage of patients presenting with a debrided wound. RESULTS: Altogether, 159 patients were randomised to either UrgoClean (test group; n=83) or Aquacel (control group; n=76) dressings. Regarding the wound healing process predictive factors (wound area, duration, ABPI value, recurrence), at baseline, the two groups were well balanced, for both wound and patient characteristics. Compression therapy was administered to both groups and after a median 42-day treatment period, the percentage of relative reduction of the wound surface area was very similar (-36.9% vs -35.4% in the UrgoClean and control groups, respectively). When considering the secondary criteria at week 6, the relative reduction of sloughy tissue was significantly higher in the UrgoClean group than in the control group (-65.3% vs -42,6%; p=0.013). The percentage of debrided wounds was also significantly higher in the test group (52.5% vs 35.1%; p=0.033). CONCLUSION: This 'EARTH' RCT confirmed that the UrgoClean dressing has similar efficacy and safety compared to Aquacel. However, UrgoClean also showed better autolytic properties than the control group in the management of venous leg ulcers at the sloughy stage. The new UrgoClean dressing therefore represents a promising therapeutic option within the current range of autolytic dressings available. DECLARATION OF INTEREST: This study was sponsored by a grant from the pharmaceutical company Laboratoires Urgo. S. Bohbot and O. Tacca are employees of Laboratoires Urgo. S. Meaume, J. Dissemond and G. Perceau have received monetary compensation as presenters for Laboratoires Urgo. Data management and statistical analyses were conducted independently by Vertical (Paris, France).

Efficacy of two compression systems in the management of VLUs: results of a European RCT.

OBJECTIVE: To evaluate the efficacy, tolerance and acceptability an innovative two-layer system (KTwo; Laboratoires URGO) versus an established four-layer bandage system (Profore; Smith & Nephew) in the local management of venous leg ulcers. METHOD: A non-inferiority European randomised controlled trial, conducted in 37 centres, in three countries (France, U.K. and Germany), on patients presenting with venous leg ulcers (VLUs). Participants were adult, non-immunosuppressed patients who presented with non-infected, non-malignant leg ulcers, predominantly of venous origin (ABPI > 0.8), with a surface area of 2-50 cm2 and duration 1-24 months. Patients were followed-up every 2 weeks for a period of 12 weeks, or until full closure. Visits included a clinical examination, wound area tracings and photographic evidence. The primary endpoint was the percentage of leg ulcers healed after the 12 weeks, with secondary endpoints of relative wound area reduction (RWAR), absolute wound area reduction (AWAR) and the percentage of wounds with RWAR > or = 40%. RESULTS: In total, 187 patients were randomised to either the two-layer bandage (2LB, n=94) or four-layer bandage (4LB; n=93) system. The two groups were comparable,with regard to wound and patient characteristics, at baseline. By week 12, 44% of VLUs in the 2LB group and 39% in the 4LB group had healed (intention-to-treat [ITT] analysis). The per-protocol (PP) analysis showed that complete wound closure was obtained in 48% and 38% of the 2LB and 4LB groups, respectively. A non-inferiority margin within -10% is considered as demonstrating a 95% and 97.5% confidence interval (p = 0.001). The AWAR was 6.6 cm2 in the test and 4.9 cm2 in the control group. The percentage of wounds with a RWAR > OR =40% was 47% and 44% for the 2LB and 4LB systems, respectively. Pain between dressing changes was reported in 27% of the test and 40% of the control group, and the incidence of adverse events was 17% and 25%, respectively. The 2LB compression system was considered to be significantly easier to apply than the 4LB (p = 0.038). CONCLUSION: The 2LB system (KTwo) was not seen to be any less effective than a well-known 4LB system (Profore) in the management of VLUs. Furthermore, the 2LB system was considered to be easier to apply, representing an alternative to the conventional treatment with 4LB currently available. DECLARATION OF INTEREST: This study was sponsored by a grant from Laboratoires URGO, manufacturers of KTwo. S. Bohbot and A. Sauvadet are employees of Laboratoires Urgo. S. Meaume has received monetary compensation as a speaker for Laboratoires Urgo. Data management and statistical analyses were conducted by Vertical (J. C. Kerihuel; Paris, France).

Long- and Short-Range Electrostatic Fields in GFP Mutants: Implications for Spectral Tuning.

The majority of protein functions are governed by their internal local electrostatics. Quantitative information about these interactions can shed light on how proteins work and allow for improving/altering their performance. Green fluorescent protein (GFP) and its mutation variants provide unique optical windows for interrogation of internal electric fields, thanks to the intrinsic fluorophore group formed inside them. Here we use an all-optical method, based on the independent measurements of transition frequency and one- and two-photon absorption cross sections in a number of GFP mutants to evaluate these internal electric fields. Two physical models based on the quadratic Stark effect, either with or without taking into account structural (bond-length) changes of the chromophore in varying field, allow us to separately evaluate the long-range and the total effective (short- and long-range) fields. Both types of the field quantitatively agree with the results of independent molecular dynamic simulations, justifying our method of measurement.

Colliding-pulse passive harmonic mode-locking in a femtosecond Yb-doped fiber laser with a semiconductor saturable absorber.

We demonstrate a passive harmonic mode-locked femtosecond Yb-doped fiber laser employing a semiconductor saturable absorber in a colliding-pulse configuration. 380-fs pulses at 605 MHz repetition rate with >60 dB supermode suppression is achieved.

Enhanced linear and nonlinear optical phase response of AlGaAs microring resonators.

We have constructed and characterized several optical microring resonators with scale sizes of the order of 10 microm. These devices are intended to serve as building blocks for engineerable linear and nonlinear photonic media. Light is guided vertically by an epitaxially grown structure and transversely by deeply etched air-clad sidewalls. We report on the spectral phase transfer characteristics of such resonators. We also report the observation of a pi-rad Kerr nonlinear phase shift accumulated in a single compact ring resonator evidenced by all-optical switching between output ports of a resonator-enhanced Mach-Zehnder interferometer.