Iron Oxide/Polymer Core-Shell Nanomaterials with Star-like Behavior.

Embedding nanoparticles (NPs) with organic shells is a way to control their aggregation behavior. Using polymers allows reaching relatively high shell thicknesses but suffers from the difficulty of obtaining regular hybrid objects at gram scale. Here, we describe a three-step synthesis in which multi-gram NP batches are first obtained by thermal decomposition, prior to their covalent grafting by an atom transfer radical polymerization (ATRP) initiator and to the controlled growing of the polymer shell. Specifically, non-aggregated iron oxide NPs with a core principally composed of γ-Fe2O3 (maghemite) and either polystyrene (PS) or polymethyl methacrylate (PMMA) shell were elaborated. The oxide cores of about 13 nm diameter were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). After the polymerization, the overall diameter reached 60 nm, as shown by small-angle neutron scattering (SANS). The behavior in solution as well as rheological properties in the molten state of the polymeric shell resemble those of star polymers. Strategies to further improve the screening of NP cores with the polymer shells are discussed.

Preparation and Deep Characterization of Composite/Hybrid Multi-Scale and Multi-Domain Polymeric Microparticles.

Polymeric microparticles were produced following a three-step procedure involving (i) the production of an aqueous nanoemulsion of tri and monofunctional acrylate-based monomers droplets by an elongational-flow microemulsifier, (ii) the production of a nanosuspension upon the continuous-flow UV-initiated miniemulsion polymerization of the above nanoemulsion and (iii) the production of core-shell polymeric microparticles by means of a microfluidic capillaries-based double droplets generator; the core phase was composed of the above nanosuspension admixed with a water-soluble monomer and gold salt, the shell phase comprised a trifunctional monomer, diethylene glycol and a silver salt; both phases were photopolymerized on-the-fly upon droplet formation. Resulting microparticles were extensively analyzed by energy dispersive X-rays spectrometry and scanning electron microscopy to reveal the core-shell morphology, the presence of silver nanoparticles in the shell, organic nanoparticles in the core but failed to reveal the presence of the gold nanoparticles in the core presumably due to their too small size (c.a. 2.5 nm). Nevertheless, the reddish appearance of the as such prepared polymer microparticles emphasized that this three-step procedure allowed the easy elaboration of composite/hybrid multi-scale and multi-domain polymeric microparticles.

A Significant Upper Arm Injury Sustained While Learning Simon Preston's Alleluyas: A Proposal for Avoiding this Malady.

Simon Preston's Alleluyas is an organ solo of moderate difficulty written partly in the tonal language of Olivier Messiaen. While learning this piece, I experienced a slight discomfort in my right upper arm. A more severe pain developed later, over several weeks, and my right hand became partially paralyzed. Full recovery took almost 2 months. … My reversible injury was caused by playing just six bars, and it may owe something to the way I "handled" this brief section, or more likely, "footed" it.

Process evaluation of the implementation of dementia-specific case conferences in nursing homes (FallDem): study protocol for a randomized controlled trial.

BACKGROUND: Challenging behaviors exhibited by individuals with dementia might result from an unmet need that they cannot communicate directly due to cognitive restrictions. A dementia-specific case conference represents a promising means of analyzing and exploring these unmet needs. The ongoing FallDem study is a stepped-wedged, cluster-randomized trial evaluating the effects of two different types of dementia-specific case conferences on the challenging behaviors of nursing home residents. This study protocol describes the process evaluation that is conducted, along with the FallDem study.The goal of the process evaluation is to explain potential discrepancies between expected and observed outcomes, and to provide insights into implementation processes and recruitment strategies, as well as the contexts and contextual factors that promote or inhibit the implementation of dementia-specific case conferences. METHODS/DESIGN: The process evaluation will use a mixed-method design comprising longitudinal elements, in which quantitative and qualitative data will be gathered. Qualitative data will be analyzed using content analysis, documentary analysis and a documentary method. Quantitative data (standardized questionnaires) will be analyzed using descriptive statistics. Both types of data will complement one another and provide a more comprehensive picture of the different objects under investigation. DISCUSSION: The process evaluation will allow for a comprehensive understanding of the changing processes and mechanisms underlying the 'black box' of the complex intervention of the FallDem study. These findings will provide practical knowledge regarding issues related to the implementation of dementia-specific case conferences in nursing homes. TRIAL REGISTRATION: Current Controlled Trials identifier: ISRCTN20203855, registered on 10th July 2013.

Effect evaluation of two types of dementia-specific case conferences in German nursing homes (FallDem) using a stepped-wedge design: study protocol for a randomized controlled trial.

BACKGROUND: Case conferences for people with dementia and challenging behaviors (e.g., apathy) are recommended as useful tools that enable staff in nursing homes to understand the behavior of people with this type of disease. Understanding peoples' behaviors is the basis for the initiation of targeted interventions to improve the quality of care for people with dementia. Furthermore, case conferences demonstrate positive effects on burnout, dementia-specific burden, and vocational action competence of the staff. The two likely approaches for conducting case conferences include the following: A) using a structured assessment instrument, which guides the staff in understanding the residents' behaviors and B) using a narrative approach in which the staff must identify the reasons for the residents' behaviors in an unstructured manner. Case conferences are a complex intervention, and evaluating their multiple effects is challenging. The aim of this study protocol was to describe a likely solution for evaluating this type of complex intervention using a special cluster randomized trial. METHODS: In this stepped-wedged cluster randomized trial, the two interventions will be sequentially implemented every three months in a group of 12 nursing homes (clusters) with a minimum of 360 residents over 19 months (7 months of intervention for each cluster and follow-up). The primary outcome is the reduction of challenging behavior (measured with the neuropsychiatric inventory-nursing home version [NPI-NH]). Secondary outcomes are residents' quality of life, prescription of psychotropic medications, staff burnout, dementia-related stress, and vocational action competence. The effectiveness of the study will be accompanied by a process evaluation. The primary data will be analyzed using a Bayesian mixed effect model; the secondary data will be analyzed using descriptive statistics and mixed effects models. DISCUSSION: The implementation and effect measurement of complex interventions such as case conferences within a cluster randomized trial are challenging (e.g., complex and intensive training, delayed treatment effect). In this study protocol, the methodological advantages and disadvantages of using the stepped wedge design to answer the research questions are discussed. TRIAL REGISTRATION: http://www.controlled-trials.com/ISRCTN20203855; registered 10 July 2013.

Spectral tuning of the phosphorescence from metalloporphyrins attached to gold nanorods.

The spectral shape of the phosphorescence emission of organometallic porphyrin molecules is shown to be altered when these chromophores are incorporated into hybrid nanostructures with gold nanorods. This result shows that triplet-singlet transitions, which are (at least partially) dipolar forbidden, can be modified by the dipolar resonances of gold nanoparticles. By choosing nanorods of increasing aspect ratios, it is possible to match the long axis plasmon resonance of the nanorods to a specific phosphorescence transition. Consequently, the emission colour of the hybrids can be tuned.

On the role of surface charges for homogeneous freezing of supercooled water microdroplets.

Charge induced changes in homogeneous freezing rates of water have been proposed to constitute a possible link between the global atmospheric electric circuit and cloud microphysics and thus climate. We report here on high precision measurements of the homogeneous nucleation rate of charged, electro-dynamically levitated single water droplets as a function of their surface charge. No evidence has been found that the homogeneous volume specific ice nucleation rate of supercooled microdroplets is influenced by surface charges in the range between +/-200 elementary charges per µm(2). It has also been suggested that filamentation in highly electrified liquids can induce freezing at temperatures well above the homogeneous freezing limit. We report here the observation of Coulomb instabilities of highly charged droplets that are accompanied with the formation and ejection of fine filaments from the liquid supercooled droplets. Down to temperatures of 240 K, which is close to the homogeneous freezing limit of uncharged water, no filamentation induced freezing has been detected. At even lower temperatures, the droplets froze before the instability was reached. These findings rule out that filamentation exerts an important influence on ice formation in supercooled water. Combining these findings, we conclude that the surface charges (even at their maximum possible density) have no significant effect on the homogeneous ice nucleation rate of supercooled cloud droplets.

Differential effects of indole and aliphatic glucosinolates on lepidopteran herbivores.

Glucosinolates are a diverse group of defensive secondary metabolites that is characteristic of the Brassicales. Arabidopsis thaliana (L.) Heynh. (Brassicaceae) lines with mutations that greatly reduce abundance of indole glucosinolates (cyp79B2 cyp79B3), aliphatic glucosinolates (myb28 myb29), or both (cyp79B2 cyp79B3 myb28 myb29) make it possible to test the in vivo defensive function of these two major glucosinolate classes. In experiments with Lepidoptera that are not crucifer-feeding specialists, aliphatic and indole glucosinolates had an additive effect on Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) larval growth, whereas Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) and Manduca sexta (L.) (Lepidoptera: Sphingidae) were affected only by the absence of aliphatic glucosinolates. In the case of two crucifer-feeding specialists, Pieris rapae (L.) (Lepidoptera: Pieridae) and Plutella xylostella (L.) (Lepidoptera: Plutellidae), there were no major changes in larval performance due to decreased aliphatic and/or indole glucosinolate content. Nevertheless, choice tests show that aliphatic and indole glucosinolates act in an additive manner to promote larval feeding of both species and P. rapae oviposition. Together, these results support the hypothesis that a diversity of glucosinolates is required to limit the growth of multiple insect herbivores.

The genetic basis of constitutive and herbivore-induced ESP-independent nitrile formation in Arabidopsis.

Glucosinolates are a group of thioglucosides that are components of an activated chemical defense found in the Brassicales. Plant tissue damage results in hydrolysis of glucosinolates by endogenous thioglucosidases known as myrosinases. Spontaneous rearrangement of the aglucone yields reactive isothiocyanates that are toxic to many organisms. In the presence of specifier proteins, alternative products, namely epithionitriles, simple nitriles, and thiocyanates with different biological activities, are formed at the expense of isothiocyanates. Recently, simple nitriles were recognized to serve distinct functions in plant-insect interactions. Here, we show that simple nitrile formation in Arabidopsis (Arabidopsis thaliana) ecotype Columbia-0 rosette leaves increases in response to herbivory and that this increase is independent of the known epithiospecifier protein (ESP). We combined phylogenetic analysis, a screen of Arabidopsis mutants, recombinant protein characterization, and expression quantitative trait locus mapping to identify a gene encoding a nitrile-specifier protein (NSP) responsible for constitutive and herbivore-induced simple nitrile formation in Columbia-0 rosette leaves. AtNSP1 is one of five Arabidopsis ESP homologues that promote simple nitrile, but not epithionitrile or thiocyanate, formation. Four of these homologues possess one or two lectin-like jacalin domains, which share a common ancestry with the jacalin domains of the putative Arabidopsis myrosinase-binding proteins MBP1 and MBP2. A sixth ESP homologue lacked specifier activity and likely represents the ancestor of the gene family with a different biochemical function. By illuminating the genetic and biochemical bases of simple nitrile formation, our study provides new insights into the evolution of metabolic diversity in a complex plant defense system.

Detection of herpesvirus and adenovirus co-infections with diagnostic DNA-microarrays.

In immunocompromised patients, the diagnosis of infections with herpesviruses and adenoviruses relies mainly on PCR amplification of viral genomic DNA from clinical samples. In the case of co-infections with two or more viruses, single amplification of viral DNA from clinical samples has proven to be time-consuming and expensive, hampering the efficient diagnosis and therapy of viral co-infections. In this study, a diagnostic DNA-microarray allowing simultaneous detection of herpes simplex virus types 1 and 2 (HSV 1/2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpesvirus-6 types A and B (HHV-6 A/B), and adenovirus in clinical samples was developed and validated. The assay displays a high analytical sensitivity (10genomeequivalents(GE)/reaction) and specificity, being cost-effective and time-saving. Because the DNA-microarray uses the same analytical conditions as real-time quantitative PCR, it can be used as a screening device for multiple viral infections, followed by selective viral load measurement depending on the clinical context. Those features make the DNA-microarray an attractive device for the management of viral infections in immunocompromised patients.

[Ogilvie's syndrome (acute idiopathic colonic pseudo-obstruction) after Caesarean section]. / Ogilvie-Syndrom (akute idiopathische Kolondilatation) nach Sectio caesarea.

Due to incipient HELLP syndrome and no progression in labour, a caesarean was performed on a 33-year-old para I gravida I. During the operation she suffered a heavy blood loss as a result of uterine inertia. In the postoperative stage she developed an acute idiopathic colonic pseudo-obstruction, also known as Ogilvie's syndrome. Only 6 days after the operation did she slowly recover. Additional factors that could have led to Ogilvie's syndrome are the caesarean, the HELLP syndrome and the postpartal haemorrhage. Due to her reduced physical health, the mobilization of the patient was restricted, which further prolonged the recovery. However, an early initiation of supportive treatment, the timely diagnosis of Ogilvie's syndrome and two colonoscopic decompressions prevented a caecal rupture. After 3 weeks of hospitalization, the patient was discharged in good general health.

Altered glucosinolate hydrolysis in genetically engineered Arabidopsis thaliana and its influence on the larval development of Spodoptera littoralis.

The antiherbivore potential of the glucosinolate-myrosinase defense system found in plants of the order Capparales is heavily influenced by the types of hydrolysis products (e.g. isothiocyanates, nitriles) formed from the parent glucosinolates upon plant damage. However, comparison of the effects of glucosinolate hydrolysis products on insect herbivores has been hampered by the lack of suitable experimental tools for rigorous bioassays, such as intact plants differing only in the types of hydrolysis products they produce, or artificial diets that can accurately simulate glucosinolate hydrolysis. The wide array of molecular resources for Arabidopsis thaliana has facilitated the identification of several genes that play a role in glucosinolate hydrolysis. One of these encodes the epithio-specifier protein (ESP) that promotes the formation of nitriles at the expense of isothiocyanates in certain ecotypes of A. thaliana. We overexpressed the ESP cDNA from the nitrile-producing ecotype Landsberg erecta in the isothiocyanate-producing ecotype Columbia-0 to generate transgenic lines of A. thaliana that differed from wild-type plants in the type of glucosinolate hydrolysis products formed upon tissue damage, whereas parent glucosinolate profile and myrosinase activity levels, as well as plant morphology and growth habit, remained unchanged. Bioassays with the model generalist herbivore Spodoptera littoralis (Lepidoptera: Noctuidae) demonstrated that larvae reared on the nitrile-producing lines on average gained weight faster in the first larval stages than larvae that fed on isothiocyanate-producing control plants. Furthermore, larvae with medial growth rates showed a tendency to pupate earlier on the ESP-overexpressing plant lines. Together with the results of previous studies, these findings suggest that isothiocyanates are more effective defenses against insect herbivores than nitriles, and raise questions about what conditions select for nitrile formation in plants.

GJB2 mutations in the Swiss hearing impaired.

OBJECTIVE: Mutations in the GJB2 gene encoding connexin 26 (Cx26) protein are a major cause for nonsyndromic autosomal recessive and sporadic deafness. However, its contribution to hearing impairment in Switzerland remains undefined. To determine the frequency and type of GJB2 mutations in the Swiss hearing-impaired population diagnosed under the age of 2 yr and at 2 yr and older and to assess the effectiveness of denaturing high-performance liquid chromatography (DHPLC) in screening for mutation in GJB2. METHODS: Thirty-four patients with hearing impairment underwent mutation screening of the single coding exon of GJB2 with DHPLC followed by bidirectional sequencing to identify sequence alterations. RESULTS: GJB2 mutations were more common in children diagnosed with hearing impairment under the age of 2 yr compared to the group 2 yr and older. In patients under age 2 yr, 9 of 20 (45%) harbored 13 GJB2 mutations including a common 313del14nt mutation; four of these patients were homozygous or compound heterozygous for GJB2 mutations. In contrast, 2 of 14 patients in the 2 yr and older group (14%) had a single mutation in GJB2. The 35delG mutation was exclusively found in 5 patients under the age of 2 yr. DHPLC for mutation screening was 100% sensitive and 83% specific for detecting sequence alterations in GJB2. CONCLUSIONS: In Switzerland, GJB2 mutations are a major cause of nonsyndromic hearing impairment in children under the age of 2. Similar to other populations, GJB2 mutations are uncommon in the affected Swiss patients identified after 2 yr. Although 35delG mutation is common in the hearing-impaired children under the age of 2, it was absent in patients diagnosed with hearing impairment after the age of 2. DHPLC is a highly sensitive tool for detection of GJB2 mutations.

Sindrome Nefrótico en PediatríA, Revisión de casos

Se realizó un estudio descriptivo de 28 pacientes comprendidos entre las edades de 1 a 5 años que presentaban síndromes nefróticos, el sexo más frecuente fue el masculino con 19 casos, el objetivo del estudio fue el de conocer el comportamiento clínico del sindrome nefrótico, en la edad infantil,las complicaciones, el manejo de estos en la sala de pediatría, sus controles enconsulta externa y el tipo de tratamiento aplicado. El principal síntoma encontrado fue el edema en un 100, siendo el edema generalizado con 20 casos, seguido de oliguria y decaimiento, otros síntomas fueron: hipertemia, tos, diarrea, dolor abdominal y vómitos. Las principales enfermedades asociadas al síndrome nefrótico fueron la neumonía, diarrea y la faringoamigdalitis; viéndose las dos primeras con mayor frecuencia tanto al ingreso como al reingreso. Las complicaciones encontradas fueron un caso con síndrome de Fanconi y un caso con insuficiencia cardíaca congestiva más insuficiencia renal aguda...