Preparation of chondroitin sulfate nanocapsules for use as carries by the interfacial polymerization method

In this paper, the method of interfacial polymerization in emulsion was employed to fabricate chondroitin sulfate-methacrylate (ChSMA) nanocapsules, in which poor water-soluble drug of indomethacin (IND) could be effectively encapsulated. The morphology and the size distribution of synthesized nanocapsules were characterized by field emission scanning electron microscopy (FESEM) and dynamic light scattering (DLS) techniques. The quantitative drug loading was investigated. The IND/ChSMA noodle-like self-assemblies were observed with the increase of IND feed concentration, and the interactions between IND and ChSMA were illuminated by FT-IR and XRD measurements. The in vitro drug release of IND-loaded nanocapsules and IND/ChSMA self-assemblies were also carried out in simulated body fluid pH 7.4 at 37 °C.     

Aureolic acids from a marine-derived Streptomyces sp. WBF16

A marine-derived actinomycete (Streptomyces sp. WBF16) exhibiting antitumor activities was investigated. The strain was identified using morphological, biochemical and genetic techniques. 16S rDNA sequence of the isolate indicated that it was most closely related to Streptomyces coelicolor A3 (2). Furthermore, a new aureolic acid (Chromomycin B, 1), along with Chromomycin A₂ (2) and Chromomycin A₃ (3) were isolated from its secondary metabolites. Their structures were determined by chemical and spectroscopic methods including 1D, 2D NMR and HRMS. Compounds 1–3 showed strong cytotoxicity against SGC7901, HepG2, A549, HCT116 and COC1 and HUVEC.     

Alizarin red S/copper ion-based ensemble for fluorescence turn on detection of glutathione with tunable dynamic range

In this study, a new type of rapid, high sensitive and selective fluorescence turn-on assay for detection of glutathione using an Alizarin Red S/copper ion ensemble is developed. This assay is based on the highly specific interaction between the glutathione and the copper ions and the strong fluorescence Alizarin Red S probe in a competition assay format. The system is simple in design, fast in operation and is more convenient and promising than other methods. The novel strategy eliminated the separation process, chemical modifications, and sophisticated instrumentations. The detection and discrimination process can be seen with the naked eye and can be easily adapted to automated high-throughput screening. The assay has high sensitivity and selectivity for glutathione. The detection limit is 2.3nM, it is lower than or at least comparable to previous methods. The dynamic range of the sensor can be tuned simply by adjusting the concentration of copper ions. Importantly, the protocol offers high selectivity for the determination of glutathione among amino acids found in proteins, as well as in serum samples. The assay shows great potential for practical application as a disease-associated biomarker and it will be needed to satisfy the great demand of amino acid determination in the fields such as biochemistry, pharmaceuticals, and clinical analysis.     

Early development of bacterial community diversity in emergently placed urinary catheters

ABSTRACT: BACKGROUND: Approximately 25% of hospitalized patients have a urinary catheter, and catheter associated urinary tract infection is the most common nosocomial infection in the US, causing >1 million cases/year. However, the natural history of the biofilms that rapidly form on urinary catheters and lead to infection is not well described. FINDINGS: We characterized the dynamics of catheter colonization among catheters collected from 3 women and 5 men in a trauma burn unit with different indwelling times using TRFLP and culture. All patients received antibiotic therapy. Results: Colony-forming units increased along the extraluminal catheter surface from the catheter balloon to the urethra, but no trend was apparent for the intraluminal surface. This suggests extraluminal bacteria come from periurethral communities while intraluminal bacteria are introduced via the catheter or already inhabit the urine/bladder. Richness of operational taxonomic units (OTUs) increased over time on the intraluminal surface, but was constant extraluminally. CONCLUSIONS: OTU community composition was explained best by time rather than axial location or surface. Our results suggest that catheter colonization can be very dynamic, and possibly have a predictable succession.     

Saliency processing and obesity: a preliminary imaging study of the stop signal task

Obesity has been associated with altered cerebral functions including cognitive control. The stop signal task (SST) has been widely used to study cognitive control by producing high conflict stop trials among many low conflict go trials. Contrasting these stop trials with go trials provides a measure of saliency processing and response inhibition. By comparing functional magnetic resonance images of obese (BMI >30) and lean (BMI <22) females performing the SST, we observed differences in regional brain activations despite similar behavioral performance between groups. Specifically, lean females had greater activations in the insula, inferior parietal cortex, cuneus, and supplementary motor area than obese females during stop as compared to go trials. This difference was caused by diminished brain activations in obese females in stop as compared to go trials. Furthermore, the brain activations in these regions inversely correlated to BMI across subjects. These preliminary findings suggest altered neural processes of cognitive control in obesity.     

Dynamic regulation of the cerebral cavernous malformation pathway controls vascular stability and growth

Cardiovascular growth must balance stabilizing signals required to maintain endothelial connections and network integrity with destabilizing signals that?enable individual endothelial cells to migrate and proliferate. The cerebral cavernous malformation (CCM) signaling pathway utilizes the adaptor protein CCM2 to strengthen endothelial cell junctions and stabilize vessels. Here we identify a CCM2 paralog, CCM2L, that is expressed selectively in endothelial cells during periods of active cardiovascular growth. CCM2L competitively blocks CCM2-mediated stabilizing signals biochemically, in cultured endothelial cells, and in developing mice. Loss of CCM2L reduces endocardial growth factor expression and impairs tumor growth and wound healing. Our studies identify CCM2L as a molecular mechanism by which endothelial cells coordinately regulate vessel stability and growth during cardiovascular development, as well as postnatal vessel growth.