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Polyelectrolyte multilayer (PEM) capsules engineered with active elements for targeting, labeling, sensing and delivery hold great promise for the controlled delivery of drugs and the development of new sensing platforms. PEM capsules composed of biodegradable polyelectrolytes are fabricated for intracellular delivery of encapsulated cargo (for example peptides, enzymes, DNA, and drugs) through gradual biodegradation of the shell components. PEM capsules with shells responsive to environmental or physical stimuli are exploited to control drug release. In the presence of appropriate triggers (e.g., pH variation or light irradiation) the pores of the multilayer shell are unlocked, leading to the controlled release of encapsulated cargos. By loading sensing elements in the capsules interior, PEM capsules sensitive to biological analytes, such as ions and metabolites, are assembled and used to detect analyte concentration changes in the surrounding environment. This Review aims to evaluate the current state of PEM capsules for drug delivery and sensing applications. © 2014 Elsevier B.V.

Congenital muscular dystrophies due to defects in genes encoding proteins involved in α-dystroglycan (α-DG) glycosylation are a heterogeneous group of muscle disorders variably associated with central nervous system and eye abnormalities. One of the more severe is muscle-eye-brain disease (MEB). Mutations in genes coding for proven or putative glycosyltransferases (POMT1, POMT2, POMGnT1, fukutin, FKRP, and LARGE), the DPM3 gene encoding a DOL-P-Man synthase subunit, and the DAG1 gene encoding α-dystroglycan, have been associated with altered α-DG glycosylation. We report new POMGnT1 mutations and evaluate protein expression in 3 patients and 2 foetuses with variably severe MEB features. We identify two new point mutations (c.643 C > T, c.1863delC), one new intragenic rearrangement (deletion of exons 2–8), and a new intron retention (between exons 21 and 22) resulting from a known point mutation c.1895 + 1 G > T. Our study provides further evidence that rearrangements of the POMGnT1 gene are relatively common. Importantly, if heterozygous, they can be missed on standard genomic DNA sequencing. POMGNT1 protein analysis in 3 patients showed that the severity of the phenotype does not correlate with protein expression. Cerebral MRI is important for identifying MEB and α-dystroglycanopathy phenotypes in children and foetuses, and hence for directing the genetic analysis.

The role of the substrate in influencing the structure and morphology of α,ω-dihexyl-quaterthiophene (DH4T) thin films grown by organic molecular beam deposition was investigated by means of atomic force microscopy (AFM) imaging and optical absorption measurements. Silica and potassium acid phthalate (KAP) substrates were selected as representative of inorganic amorphous and organic crystalline substrates, respectively. The film growth mechanism was found to depend on the flatness, cleanliness, and structure of the substrate, which influence the overgrown film.

The principle of ligand exchange has been applied to the enantioseparation of underivatized aromatic and aliphatic amino acids as well as dipeptides. Two non commercially available N-alkyl- l -4-hydroxyproline derivatives were compared to underivatized l -4-hydroxyproline for their ability to resolve α-amino acids and dipeptides. N-(2-hydroxyoctyl)- l -4-hydroxyproline and N-(2-hydroxypropyl)- l -4-hydroxyproline were used as their copper(II) complexes as chiral selectors. With these selectors, several aliphatic amino acids and dipeptides, in addition to aromatic amino acids, were resolved. The pH optimum was found to be 4.3 for amino acids and 6.0 for dipeptides.

Olivine single crystals from a pallasitic meteorite have been found to undergo a peculiar ordering process with increasing temperature consisting of a noticeable Fe segregation into site M1 up to around 900°C, followed by a sudden ordering reversal with Fe progressively and strongly segregating into site M2 as the temperature is increased up to our experimental limit of 1300°C. The speed of the exchange reactions has baffled all previous quenching studies from temperatures above about 800°C. The details of the ordering process at temperatures close to the transition temperature were determined in situ from single frames of data collected using the time-of-flight Laue method. The constrained refinements obtained from these data yield lower precision than full data sets but allow the ordering to be characterised rapidly and reliably. The power of this method in monitoring such phase transitions is discussed. The far reaching geological implications of our findings are considered.

High performance liquid chromatography (HPLC) with electrochemical detection proves to be a reliable method for determination of plasma catecholamines (CA) to assess the possible role of the sympathetic nervous system (SNS) in essential hypertension (EH). The present investigation in a group of 15 normotensive (N) and 13 stable EH patients, homogeneous for age and duration of hypertension, was carried out without treatment in the supine position, up-right position and during a personalized bicycle exercise. Mean blood pressure, mean heart rate, plasma renin activity and plasma aldosterone were also evaluated at the various exertion phases. Norepinephrine (NE) and epinephrine (E) showed a progressive increase in N and in EH patients, reaching the highest values at maximum effort. However, EH patients showed higher E plasma levels than N before maximum effort. Dopamine (DA) reached the highest values in N at maximum effort and in EH patients at recovery time. These findings allow us to foresee the possibility of a better characterization of the SNS role in EH.

Summary Cryptococcosis and aspergillosis in immunocompromised patients are extremely difficult clinical conditions to manage and treatment with available antifungal drugs often fails. Itraconazole, R-51211, Janssen Pharmaceutica, a new orally absorbed triazole, is a possible alternative drug which is potentially effective and nontoxic. Preliminary experience with 28 patients, eight with cryptococcosis and 20 with aspergillosis, is reported. Of these patients, 16 were immunocompromised (seven with the acquired immune-deficiency syndrome (AIDS), five heart transplant recipients and four with leukaemia or lymphoma). Overall, results of treatment were good (18 in remission, four markedly improved, four moderately improved and two failed). Prevention of relapses of cryptococcosis was obtained in all patients with AIDS on long-term itraconazole monotherapy (3 mg/kg). Treatment of invasive aspergillosis required a higher dosage (about 5 mg/kg) and prolonged administration. Besides its efficacy this antifungal agent allowed outpatient management.

A representative series of levyne samples shows a remarkably homogeneous chemical composition revealed by electron microprobe and thermogravimetric analyses (t.g.a.). The lattice parameters, accurately determined by X-ray powder diffractometry and refined by least squares treatment, have weak correlations with selected chemical parameters in accord with their very limited range of variation (average values with e.s.d., a = 1.335(3) nm, c = 2.289(12) nm). The fairly constant chemical and physical parameters of levyne are a distinguishing feature of this zeolite family and may testify to its narrow range of crystallization conditions. Levyne is often intimately associated with erionite and/or offretite, possibly in response to the changes of equilibrium conditions.

Two piezoelectric constants (polarization per unit stress, d=d'-id'', and polarization per unit strain, e=e'-ie''), the elastic constant, and dielectric constant are determined for oriented collagen at different hydration levels at 10 Hz from -150 to 50 degrees C. With no hydration (approximately 0% H2O), d' increases slightly with higher temperatures, while e' decreases slightly. Near 11 wt% H2O, both d' and e' increase then decrease around 0 degrees C, and is probably caused by an increase of the dielectric constant and the ionic conductivity in the nonpiezoelectric phase. Hydration greater than 25 wt%, d' and e' decrease above -50 degrees C which is considered to be due to a greater ionic conductivity surrounding the piezoelectric phase.

Resume La poussiere domestique est une mosaique antigenique, dans laquelle les acariens representent vraisemblablement les antigenes dominants. Les auteurs ont etudie 150 allergiques a la poussiere (asthmes, rhinites, tracheites), en comparant les taux d'IgE de deux groupes de malades definis par les tests cutanes : le premier groupe comprend 56 allergiques a la poussiere seule ; le deuxieme groupe, 94 allergiques a la poussiere et aux acariens. La comparaison des taux moyens d'IgE est statistiquement tres significative : la moyenne du second groupe (94) est tres superieure a la moyenne du premier (56) ; ceci permet de completer, par un argument immunologique, la silhouette de l'allergique sensible, simultanement, a la poussiere et aux acariens. Ces acariens se comportent incontestablement comme des antigenes puissants dont il faut tenir compte dans les desensibilisations specifiques.