Antimicrobial lubricant formulations containing poly(hydroxybenzene)-trimethoprim conjugates synthesized by tyrosinase

Poly(hydroxybenzene)-trimethoprim conjugates were prepared using methylparaben as substrate of the oxida- tive enzyme tyrosinase. MALDI-TOF MS analysis showed that the enzymatic oxidation of methylparaben alone leads to the poly(hydroxybenzene) formation. In the presence of tri- methoprim, the methylparaben tyrosinase oxidation leads poly(hydroxybenzene)-trimethoprim conjugates. All of these compounds were incorporated into lubricant hydroxyethyl cellulose/glycerol mixtures. Poly(hydroxybenzene)-trimetho- prim conjugates were the most effective phenolic structures against the bacterial growth reducing by 96 and 97 % of Escherichia coli and Staphylococcus epidermidis suspen- sions, respectively (after 24 h). A novel enzymatic strategy to produce antimicrobial poly(hydroxybenzene)-antibiotic conjugates is proposed here for a wide range of applications on the biomedical field.The authors Idalina Gonçalves and Cláudia Botelho would like to acknowledge the NOVO project (FP7-HEALTH- 2011.2.3.1- 5) for funding. Loïc Hilliou acknowledges the financial support by FCT – Foundation for Science and Technology, Portugal (501100001871), through Grant PEst-C/CTM/LA0025/2013 - Strategic Project - LA 25 - 2013–2014, and by Programa Operacional Regional do Norte (ON.2) through the project BMatepro – Optimizing Materials and Processes^, with reference NORTE-07-0124-FEDER-000037 FEDER COMPETE

Therapeutic Effects of Liposome-Enveloped Ligusticum chuanxiong Essential Oil on Hypertrophic Scars in the Rabbit Ear Model

Hypertrophic scarring, a common proliferative disorder of dermal fibroblasts, results from an overproduction of fibroblasts and excessive deposition of collagen. Although treatment with surgical excision or steroid hormones can modify the symptoms, numerous treatment-related complications have been described. In view of this, we investigated the therapeutic effects of essential oil (EO) from rhizomes of Ligusticum chuanxiong Hort. (Umbelliferae) on formed hypertrophic scars in a rabbit ear model. EO was prepared as a liposomal formulation (liposome-enveloped essential oil, LEO) and a rabbit ear model with hypertrophic scars was established. LEO (2.5, 5, and 10%) was applied once daily to the scars for 28 days. On postoperative day 56, the scar tissue was excised for masson's trichrome staining, detection of fibroblast apoptosis, assays of the levels of collagens I and III, and analysis of the mRNA expression of matrix metalloproteinase-1 (MMP-1), caspase-3 and -9, and transforming growth factor beta 1 (TGF-β1). In addition, the scar elevation index (SEI) was also determined. As a result, LEO treatment significantly alleviated formed hypertrophic scars on rabbit ears. The levels of TGF-β1, MMP-1, collagen I, and collagen III were evidently decreased, and caspase -3 and -9 levels and apoptosis cells were markedly increased in the scar tissue. SEI was also significantly reduced. Histological findings exhibited significant amelioration of the collagen tissue. These results suggest that LEO possesses the favorable therapeutic effects on formed hypertrophic scars in the rabbit ear model and may be an effective cure for human hypertrophic scars

Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

Contains fulltext : 172380.pdf (publisher's version ) (Open Access

Cetirizine from topical phosphatidylcholine-hydrogenated liposomes: Evaluation of peripheral antihistaminic activity and systemic absorption in a rabbit model

Cetirizine, an effective, minimally sedating, second-generation H1-antihistamine is widely used orally to treat allergic skin disorders. This study was performed to assess the peripheral H1-antihistaminic activity and extent of systemic absorption of cetirizine from liposomes applied to the skin. Cetirizine was incorporated into small unilamellar vesicles (SUV) and multilamellar vesicles (MLV) prepared using L-α-phosphatidylcholine hydrogenated (HPC), and into Glaxal Base (GB) as the control. In a randomized, crossover study, each formulation, containing 10 mg of cetirizine, was applied to the depilated backs of 6 rabbits (3.08±0.05 kg). Histamine-induced wheal tests and blood sampling were performed before cetirizine application and at designated times for up to 24 hours afterwards. Compared with baseline, histamine-induced wheal formation was suppressed by cetirizine in SUV only at 24 hours, in MLV from 0.5 to 24 hours, and in GB from 0.5 to 8 hours (P<.05). Wheal suppression by cetirizine in SUV at 24 hours (91.7%±5.2%) and in MLV from 1 to 24 hours (93.8%±2.2% to 76.2%±6.5%) was greater than in GB (36.5%±7.4% to 60.6%±14.2%) from 1 to 24 hours (P<.05). Faster onset, as well as greater and more persistent suppression was obtained from cetirizine in MLV. Plasma cetirizine concentrations from MLV (area under the curve [AUC] of 221.2±42.3 ng.hr/mL) were lower than from GB (AUC of 248.3±34.6 ng.hr/mL). In this model, cetirizine from MLV had excellent topical H1-antihistamine activity, while systemic exposure was reduced, compared with cetirizine from GB