Robust color texture features under varying illumination conditions

Under varying illumination, both the statistical and structural contents of color texture are modified, leading to changes in the observed texture surface. We model the effect of illumination as a perturbation on an ideal color texture and show that the spectra of the ambient light have a significant impact on the observed texture patterns in the individual color channels. Motivated by studies in human color constancy, we propose a correlation-based transformation that minimizes the effect of illumination variation in color texture analysis. Experimental results are included, which validate the performance of the proposed minvariance model in the analysis of color texture.     

Tissue Programmed Hydrogels Functionalized with GDNF Improve Human Neural Grafts in Parkinson's Disease

The survival and synaptic integration of transplanted dopaminergic (DA) progenitors are essential for ameliorating motor symptoms in Parkinson's disease (PD). Human pluripotent stem cell (hPSC)-derived DA progenitors are, however, exposed to numerous stressors prior to, and during, implantation that result in poor survival. Additionally, hPSC-derived grafts show inferior plasticity compared to fetal tissue grafts. These observations suggest that a more conducive host environment may improve graft outcomes. Here, tissue-specific support to DA progenitor grafts is provided with a fully characterized self-assembling peptide hydrogel. This biomimetic hydrogel matrix is programmed to support DA progenitors by i) including a laminin epitope within the matrix; and ii) shear encapsulating glial cell line-derived neurotrophic factor (GDNF) to ensure its sustained delivery. The biocompatible hydrogel biased a 51% increase in A9 neuron specification—a subpopulation of DA neurons critical for motor function. The sustained delivery of GDNF induced a 2.7-fold increase in DA neurons and enhanced graft plasticity, resulting in significant improvements in motor deficits at 6 months. These findings highlight the therapeutic benefit of stepwise customization of tissue-specific hydrogels to improve the physical and trophic support of human PSC-derived neural transplants, resulting in improved standardization, predictability and functional efficacy of grafts for PD.     

Improving the usability of intravenous medication labels to support safe medication delivery

Medication label design is frequently a contributing factor to medication errors. Design regulations and recommendations have been predominantly aimed at manufacturers’ product labels. Pharmacy-generated labels have received less scrutiny despite being an integral artifact throughout the medication use process. This article is an account of our efforts to improve the design of a hospital’s intravenous (IV) medication labels. Our analysis revealed a set of interrelated processes and stakeholders that restrict the range of feasible label designs. The technological and system constraints likely vary among hospitals and represent significant barriers to developing and implementing specific design standards. We propose both an ideal IV label design and one that adheres to the current constraints of the hospital under study.

Relevance to industry

Hospitals are tasked with creating customized medication labels with minimal guidance. Our process, findings, and proposed labels provide insight for similar investigations at other institutions.     

Dopamine D1 and D2 Receptor Antagonism in the Preoptic Area Produces Different Effects on Maternal Behavior in Lactating Rats.

The preoptic area (POA) is critical for maternal behavior in rats but little is known about what neurotransmitters released here influence maternal responding. POA infusion of 10 μg (but not 2 μg) of the dopamine D1 receptor antagonist SCH-23390 greatly impaired retrieval and licking of pups but not other maternal or nonmaternal behaviors in lactating rats. In contrast, POA infusion of 10 μg (but not 2 μg) of the D2 receptor antagonist raclopride facilitated nursing but did not affect oral maternal behaviors. SCH-23390 in the medial hypothalamus tended to impair licking but not retrieval. Raclopride in the medial hypothalamus had no effects. Therefore, D1 and D2 receptor activity, particularly in the POA, is important for regulating different maternal behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

“Ruffled border” formation on a CaP-free substrate: A first step towards osteoclast-recruiting bone-grafts materials able to re-establish bone turn-over

Osteoclasts are large multinucleated giant cells that actively resorb bone during the physiological bone turnover (BTO), which is the continuous cycle of bone resorption (by osteoclasts) followed by new bone formation (by osteoblasts). Osteoclasts secrete chemotactic signals to recruit cells for regeneration of vasculature and bone. We hypothesize that a biomaterial that attracts osteoclasts and re-establishes BTO will induce a better healing response than currently used bone graft materials. While the majority of bone regeneration efforts have focused on maximizing bone deposition, the novelty in this approach is the focus on stimulating osteoclastic resorption as the starter for BTO and its concurrent new vascularized bone formation. A biodegradable tyrosine-derived polycarbonate, E1001(1k), was chosen as the polymer base due to its ability to support bone regeneration in vivo. The polymer was functionalized with a RGD peptide or collagen I, or blended with β-tricalcium phosphate. Osteoclast attachment and early stages of active resorption were observed on all substrates. The transparency of E1001(1k) in combination with high resolution confocal imaging enabled visualization of morphological features of osteoclast activation such as the formation of the “actin ring” and the “ruffled border”, which previously required destructive forms of imaging such as transmission electron microscopy. The significance of these results is twofold: (1) E1001(1k) is suitable for osteoclast attachment and supports osteoclast maturation, making it a base polymer that can be further modified to optimize stimulation of BTO and (2) the transparency of this polymer makes it a suitable analytical tool for studying osteoclast behavior.

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New peptolides from the cyanobacterium Nostoc insulare as selective and potent inhibitors of human leukocyte elastase

Eight new cyanopeptolins (insulapeptolides A-H) were obtained from the cyanobacterium Nostoc insulare. Their isolation was guided by their bioactivity toward the target enzyme human leukocyte elastase, molecular biological investigations, and MALDI-TOF analysis. These peptides are selective inhibitors of human leukocyte elastase with activities in the nanomolar range. Insulapeptolide D was the most potent compound with an IC(50) value of 85 nM (K(i) value of 36 nM).