Suppression of crosstalk in multielectrode arrays with local shielding

Electrical crosstalk can constrain the performance of multielectrode arrays in electro- and neurophysiology, in terms of both stimulation and recording. This is especially so at high electrode density, desirable for spatiotemporal mapping of bioelectrical signals from multiple cells. Channel interference due to crosstalk is currently only partially addressed, via continuous interleaved sampling or post-data acquisition spike sorting. Here, we show that a locally-shielded electrode architecture significantly suppresses crosstalk, and enables multi-site recording at high electrode density without the need for spike sorting. Arrays of shielded electrodes, prepared by micro- and nanofabrication techniques in a vertically-oriented coaxial geometry, demonstrate at least a 400 times improvement in spatial density over the unshielded case.

Downmodulation of key inflammatory cell markers with a topical Janus kinase 1/2 inhibitor

BACKGROUND

INCB018424 is a novel, potent Janus kinase (JAK)1/JAK2 inhibitor that blocks signal transduction of multiple proinflammatory cytokines.

OBJECTIVES

To evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics and preliminary efficacy of topical INCB018424 phosphate cream in patients with plaque psoriasis.

METHODS

Topical INCB018424 phosphate 1·0% or 1·5% cream was applied once daily (QD) or twice daily (BID) for 4 weeks to 2-20% body surface area in five sequential cohorts of five patients aged 18-65 years. Target lesions were scored on a scale of 0-4 for erythema, scaling and thickness. Additionally, the overall disease activity in each patient was measured using Physician's Global Assessment. INCB018424 concentrations were measured in plasma, and cytokine stimulated phosphorylated signal transducer and activator of transcription 3 phosphorylation (pSTAT3) levels in peripheral blood cells were evaluated. Pretreatment and post-treatment skin biopsies were compared with healthy skin, including evaluation of histopathology, immunohistochemistry and mRNA expression.

RESULTS

Treatment with INCB018424 phosphate cream either 1·0% QD or 1·5% BID resulted in improvements in lesion scores. No significant inhibition of pSTAT3 in peripheral blood cells was observed following topical application, consistent with the generally low steady-state plasma concentrations of INCB018424 measured. Transcriptional markers of immune cell lineage/activation in lesional skin were reduced by topical INCB018424, with correlations observed between clinical improvement and decreases in markers of T helper 17 lymphocyte activation, dendritic-cell activation and epidermal hyperplasia. INCB018424 treatment reduced epidermal hyperplasia and dermal inflammation in most patient samples, with reductions in CD3, CD11c, Ki67 and keratin 16 observed by immunohistochemical analysis.

CONCLUSIONS

Topical INCB018424 dosed for 28 days QD or BID is pharmacologically active in patients with active psoriasis and modulates proinflammatory cytokines in the pathogenesis of psoriatic lesions.

Prediction of elementary school children's externalizing problem behaviors from attentional and behavioral regulation and negative emotionality

The purpose of this study was to examine the moderating role of individual differences in negative emotionality in the relations of behavioral and attentional (emotional) regulation to externalizing problem behaviors. Teachers' and one parent's reports of children's regulation (attentional and behavioral), emotionality, and problem behavior were obtained when children were in kindergarten to grade 3 and two years later (N = 169; 146 in major analyses); children's behavioral regulation also was assessed with a measure of persistence. According to the best fitting structural equation model, at two ages behavioral dysregulation predicted externalizing behavior problems for children both high and low in negative emotionality, whereas prediction of problem behavior from attentional control was significant only for children prone to negative emotionality. There were unique, additive effects of behavioral and attentional regulation for predicting problem behavior as well as moderating effects of negative emotionality for attentional regulation.

Regulation, emotionality, and preschoolers' socially competent peer interactions

In this study, the relations of regulatory control to the qualities of children's everyday peer interactions were examined. Effortful control (EC) and observations of peer interactions were obtained from 135 preschoolers (77 boys and 58 girls, mean ages = 50.88 and 50.52, respectively). The results generally confirmed the prediction that children who are high in EC were relatively unlikely to experience high levels of negative emotional arousal in response to peer interactions, but this relation held only for moderate to high intense interactions. Socially competent responding was less likely to be observed when the interaction was intense or when negative emotions were elicited. Moreover, when the interactions were of high intensity, highly regulated children were likely to evidence socially competent responses. The relation of EC and intensity to social competence was partially mediated by negative emotional arousal. The results support the conclusion that individual differences in regulation interact with situational factors in influencing young children's socially competent responding.

Using hyaluronic acid to create a fetal-like environment in vitro

The fetal wound healing matrix is exceptionally rich in hyaluronic acid (HA). Fetal wounds heal without scarring or contraction. Noting these observations, we cultured adult dermal explants in the presence of various concentrations of medical-grade HA in vitro. In the presence of HA, fibroblasts migrated from the dermal explant and multiplied more rapidly than control explants. Subsequently, sterile toothpicks were used to disrupt (wound) fibroblast monolayers mechanically and the rate of closure was monitored. Cells cultivated in the presence of 5 mg/ml of exogenous HA changed in morphology and closed the wound more quickly than control cultures. Cells surrounding the wound extended numerous podalic processes and showed increased interdigitation. The effect of HA on cell proliferation is usually discussed in terms of the mechanical effects HA exerts on cells and the extracellular matrix. The physiological effect of HA may lie in its ability to act as an accessory receptor in cooperative ligand-binding pathways. For example, HA may bind growth and/or other factors, and thereby increase the effective concentration of these factors at the cell surface.

Identification of Drosophila cytoskeletal proteins by induction of abnormal cell shape in fission yeast

To clone metazoan genes encoding regulators of cell shape, we have developed a functional assay for proteins that affect the morphology of a simple organism, the fission yeast Schizosaccharomyces pombe. A Drosophila melanogaster cDNA library was constructed in an inducible expression vector and transformed into S. pombe. When expression of the Drosophila sequences was induced, aberrant cell shapes were found in 0.2% of the transformed colonies. Four severe phenotypes representing defects in cytokinesis and/or cell shape maintenance were examined further. Each displayed drastic and specific reorganizations of the actin cytoskeleton. Three of the cDNAs responsible for these defects appear to encode cytoskeletal components: the actin binding proteins profilin and cofilin/actin depolymerizing factor and a membrane-cytoskeleton linker of the ezrin/merlin family. These results demonstrate that a yeast phenotypic screen efficiently identifies conserved genes from more complex organisms and sheds light on their potential in vivo functions.

Mental rotation: effects of dimensionality of objects and type of task

The original studies of mental rotation estimated rates of imagining rotations that were much slower when two simultaneously portrayed three-dimensional shapes were to be compared (R. Shepard & J. Metzler) than when one two-dimensional shape was to be compared with a previously learned two-dimensional shape (Cooper and her associates). In a 2 X 2 design, we orthogonally varied dimensionality of objects and type of task. Both factors affected reaction times. Type of task was the primary determiner of estimated rate of mental rotation, which was about three times higher for the single-stimulus task. Dimensionality primarily affected an additive component of all reaction times, suggesting that more initial encoding is required for three-dimensional shapes. In the absence of a satisfactory way of controlling stimulus complexity, the results are at least consistent with the proposal that once three-dimensional objects have been encoded, their rotation can be imagined as rapidly as the rotation of two-dimensional shapes.