Contact allergy in chronic leg ulcers: results of a multicentre study carried out in 423 patients and proposal for an updated series of patch tests

Background:  There is a lack of prospective studies investigating contact sensitization in patients with chronic leg ulcers.
Objectives:  To determine the frequency of contact sensitization in patients with chronic leg ulcers using a special series of patch tests and to determine whether the number of sensitizations was correlated with the duration of the chronic leg ulcers.
Patients/methods:  Multicentre study carried out in patients with chronic leg ulcers; patch tests with the European baseline series and with an additional 34 individual allergens or mixes and 3 commercial products.
Results:  Of the 423 patients (301 women, 122 men, mean age 68.5 years) with chronic leg ulcers, 308 (73%) had at least one positive patch test with 3.65 positive patch tests per patient. The main allergens were Myroxylon pereirae (41%), fragrance mix I (26.5%), antiseptics (20%), and corticosteroids (8%). The number of positive tests per patient was not correlated with the cause of ulcer but was increased with the duration of the ulcer with a statistical difference between the group of the <1 year compared with the group >10 years duration.
Conclusions:  From this large prospective multicentre study, polysensitization is frequent in patients with chronic leg ulcers, increasing with the duration of the ulcer. We propose avoidance of topical antiseptics and ointments containing perfumes in patients with chronic leg ulcers and an updated patch test series for investigating these patients.     

Artificial metalloenzymes based on biotin-avidin technology for the enantioselective reduction of ketones by transfer hydrogenation

Most physiological and biotechnological processes rely on molecular recognition between chiral (handed) molecules. Manmade homogeneous catalysts and enzymes offer complementary means for producing enantiopure (single-handed) compounds. As the subtle details that govern chiral discrimination are difficult to predict, improving the performance of such catalysts often relies on trial-and-error procedures. Homogeneous catalysts are optimized by chemical modification of the chiral environment around the metal center. Enzymes can be improved by modification of gene encoding the protein. Incorporation of a biotinylated organometallic catalyst into a host protein (avidin or streptavidin) affords versatile artificial metalloenzymes for the reduction of ketones by transfer hydrogenation. The boric acid.formate mixture was identified as a hydrogen source compatible with these artificial metalloenzymes. A combined chemo-genetic procedure allows us to optimize the activity and selectivity of these hybrid catalysts: up to 94% (R) enantiomeric excess for the reduction of p-methylacetophenone. These artificial metalloenzymes display features reminiscent of both homogeneous catalysts and enzymes.     

Emergency Department influenza vaccination campaign allows increasing influenza vaccination coverage without disrupting time interval quality indicators

To evaluate the impact of an influenza vaccination (IV) coverage (IVC) in a vaccination campaign of an Emergency Department (EDVC) and its impact on ED time interval quality indicators. We conducted a 4 year observational study, with an intervention during the 4th year. IVC was calculated during pre-and early-epidemic periods. During the final period, a 12 weeks EDVC was implemented. Physicians and nurses were trained and sensitized in the importance of vaccination, and their role in the prevention of severe forms of influenza was reinforced. The vaccine was proposed by physicians and nurses, and delivered by them. Repeated measures ANOVA is a validated method for related not independent groups (https://statistics.laerd.com/statistical-guides/repeated-measures-anova-statistical-guide.php). Overall, IVC was 987/3191 (30.9%) with an increasing trend from 28.8 to 33.2%. In the fourth period, out of 868 patients identified with IV indication, 288 had already been vaccinated (IVC?33.2%). After excluding patients presenting criteria of exclusion, IV was proposed to 475 patients: 317 (66.7%) accepted. The vaccination rate after patient’s acceptance was 89.6% (288/317). At the end of the EDVC, influenza vaccination coverage was 572 (284?+?288)/868 (65.9%). The delay between arrival at the ED and seeing the triage nurse and physician as well as the overall ED length of stay were not modified during the study period and before and during EDVC. EDVC effectively doubled the influenza vaccination coverage, without modifying ED time interval quality indicators.