Microencapsulation of benzalkonium chloride enhanced its antibacterial and antibiofilm activities against Listeria monocytogenes and Escherichia coli.

AIMS: In this study, benzalkonium chloride (BAC) microcapsules were developed for surface disinfection purpose and were evaluated against Listeria monocytogenes and Escherichia coli biofilms. METHODS AND RESULTS: Microcapsules were prepared with two different strategies: uncomplexed BAC-microcapsules (UBM) containing BAC and maltodextrins, and complexed BAC-microcapsules (CBM) containing BAC complexed by pectin and maltodextrins. The minimum inhibitory concentrations (MICs) of free and microencapsulated BAC were investigated against two food pathogens: L. monocytogenes and E. coli. The antibiofilm activities of UBM and CBM against L. monocytogenes and E. coli biofilms formed on stainless steel at 37°C were evaluated and compared to BAC used under its free form. MICs of encapsulated BAC were up to fourfold lower than those of free BAC. The UBM and CBM showed higher antibiofilm effect when compared to the free BAC. CONCLUSIONS: Overall, results demonstrated that microencapsulation enhanced the antibacterial activity of BAC against L. monocytogenes and E. coli biofilms. SIGNIFICANCE AND IMPACT OF THE STUDY: The application of such BAC microcapsule-based delivery systems can improve surface disinfection procedures and reduce the required BAC concentrations and the related cytotoxicity of this antimicrobial compound.

Encapsulation of a TRPM8 Agonist, WS12, in Lipid Nanocapsules Potentiates PC3 Prostate Cancer Cell Migration Inhibition through Channel Activation.

In prostate carcinogenesis, expression and/or activation of the Transient Receptor Potential Melastatin 8 channel (TRPM8) was shown to block in vitro Prostate Cancer (PCa) cell migration. Because of their localization at the plasma membrane, ion channels, such as TRPM8 and other membrane receptors, are promising pharmacological targets. The aim of this study was thus to use nanocarriers encapsulating a TRPM8 agonist to efficiently activate the channel and therefore arrest PCa cell migration. To achieve this goal, the most efficient TRPM8 agonist, WS12, was encapsulated into Lipid NanoCapsules (LNC). The effect of the nanocarriers on channel activity and cellular physiological processes, such as cell viability and migration, were evaluated in vitro and in vivo. These results provide a proof-of-concept support for using TRPM8 channel-targeting nanotechnologies based on LNC to develop more effective methods inhibiting PCa cell migration in zebrafish xenograft.

Carbon nanowalls: a new versatile graphene based interface for the laser desorption/ionization-mass spectrometry detection of small compounds in real samples.

Carbon nanowalls, vertically aligned graphene nanosheets, attract attention owing to their tunable band gap, high conductivity, high mechanical robustness, high optical absorbance and other remarkable properties. In this paper, we report for the first time the use of hydrophobic boron-doped carbon nanowalls (CNWs) for laser desorption/ionization of small compounds and their subsequent detection by mass spectrometry (LDI-MS). The proposed method offers sensitive detection of various small molecules in the absence of an organic matrix. The CNWs were grown by microwave plasma enhanced chemical vapor deposition (MW-PECVD), using a boron-carbon gas flow ratio of 1200 in H2/CH4 plasma, on silicon <100> wafer. The hydrophobicity of the surface offers a straightforward MS sample deposition, consisting of drop casting solutions of analytes and drying in air. Limits of detection in the picomolar and femtomolar ranges (25 fmol µL-1 for neurotensin) were achieved for different types of compounds (fatty acids, lipids, metabolites, saccharides and peptides) having clinical or food industry applications. This rapid and sensitive procedure can also be used for quantitative measurements without internal standards with RSDs <19%, as in the case of glucose in aqueous solutions (LOD = 0.32 ± 0.02 pmol), blood serum or soft drinks. Moreover, melamine (63 ± 8.19 ng µL-1), a toxic compound, together with creatinine and paracetamol, was detected in urine samples, while lecithin was detected in food supplements.

Early specialized care after a first unprovoked epileptic seizure.

A first seizure is a life-changing event with physical and psychological consequences. We aimed to assess the role of early comprehensive patient care after a first unprovoked seizure to improve diagnostic accuracy and follow-up adherence. From April 2011 to March 2012, patients presenting a first unprovoked epileptic seizure received standard patient care (SPC), i.e., a consultation in the ED, an EEG and a CT scan. The patients were notified of the follow-ups. We compared this protocol to subsequently acquired "early comprehensive patient care" (ECPC), which included a consultation by an epileptologist in the emergency department (ED), a routine or long-term monitoring electroencephalogram (LTM-EEG), magnetic resonance imaging and three follow-up consultations (3 weeks, 3 months, 12 months). 183 patients were included (113 ECPC, 70 SPC). LTM-EEG and MRI were performed in 51 and 85 %, respectively, of the patients in the ECPC group vs in 7 and 52 % of the patients in the SPC group (p < 0.001). A final diagnosis was obtained in 64 vs 43 % of the patients in the ECPC vs SPC group (p < 0.01). Patient attendance at 3-month was 84 % in the ECPC group vs 44 % in the SPC group (p < 0.001). At 12-month follow-up, the delay until the first recurrence was longer in the ECPC group (p = 0.008). An early epileptologist-driven protocol is associated with clinical benefit in terms of diagnostic accuracy, follow-up adherence and recurrence. This study highlights the need for epilepsy experts in the early assessment of a first epileptic seizure, starting already in the ED.

Formulation and characterization of polyphenol-loaded lipid nanocapsules.

The purpose of this study was to design and characterize two flavonoid-loaded lipid nanocapsules (LNC) by applying the phase inversion process, and to enhance their apparent solubility and/or the stability. The flavonoid-loaded LNC were characterized by particle size, encapsulation efficiency, drug leakage rates, stability and spectroscopic studies. It was observed that quercetin-loaded LNC30 (3%) and LNC60 (2%) carried a particle size of 30.3 and 55.1 nm, respectively and significant higher entrapment efficiency. Encapsulation of quercetin (QC) in LNC enabled us to increase its apparent aqueous solubility by a factor of 100. And in view of calculations and results, it seems most probable that QC is arranged at this LNC interface between the oil phase and the hydrophilic polyethylene glycol moieties of the surfactant. In addition, colloidal suspensions proved to be stable in term of encapsulation for at least 10 weeks and QC was not oxidised. With simple chemical modification of (-)-epigallocatechin-3-gallate or (-)-EGCG, it was possible to reach very high encapsulation rates (95%). Thus we obtained stable colloidal suspensions of (-)-EGCG in water over 4 weeks while free (-)-EGCG solubilised in water exhibited 100% degradation within 4h. The initial problems (solubility and stability) of these flavonoids were resolved thanks to drug-loaded LNC.