Protease-Activated Quantum Dot Probes

Protease activity has been demonstrated to be an important prognostic and predictive marker in diseases such as cancer and stroke. As such, much attention has been given to the development of diagnostic tools that would allow one to assay their activity in living tissues. Protease activity is regulated at many levels including transcription, translation, activation, and inhibition and in order to derive the maximum prognostic benefit, it is essential to study their activity within this complex environment. Initial attempts to accomplish this goal involved the use of organic fluorophores pairs that utilize Fluorescence Resonance Energy Transfer (FRET) but suffered many drawbacks. Quantum Dots (QD) have addressed many of the drawbacks of organic fluorophores in various optical imaging applications. These include a decreased sensitivity to photobleaching and chemical degradation, size-tunable narrow emission peaks, and broad absorbance allowing excitation of multiple peak emission QD by one excitation source. In this work, we propose to utilize Quantum Dots (QD) linked to gold nanoparticles (AuNPs) by protease cleavable peptide sequences to serve as probes for assaying protease activity both in vivo and in vitro. This work involved the synthesis and characterization of the various components necessary for the probe design as well as the optimization of probe characteristics to achieve highly biocompatible probes that exhibit both a high level of quenching and maximum fluorescence recovery in the presence of protease. Probe functionality was optimized and it was determined that probes with AuNP:QD ratio of 10.1 and peptide linker length of 6.5 nm resulted in highest and most linear fluorescent signal gain. The ability to multiplex probes was also validated by developing spectrally orthogonal probes sensitive to collagenase and cathepsin K. Our design is expected to have many applications in the research and understanding of the role of proteases in disease and as a predictive tool for the prognosis of diseases such as cancer

URBAN DESIGN ANALYSIS OF NEW YORK CITY’S VIRTUAL MODEL - THE CASE OF TOM CLANCY’S THE DIVISION

People have started spending time with digital tools and virtual worlds to escape reality\u27s horrors. However, designed spaces are more than the players\u27 needs, especially those digital games that their stories involve urban environments. This inefficiency causes spending futile efforts both in time and cost for the digital games\u27 productions; The urban environments in these digital games are replicas of real-world cities. Some companies use some techniques for downgrading replicas. Therefore, this study aims to uncover the used techniques for designing Tom Clancy\u27s The Division (2016). By using reverse engineering methodology and qualitative comparative analysis, the in-game map compared with the real-world map. Based on the results, the used techniques allowed the designers to scale down the game environment to be 2.5 times smaller than the actual city. Rather, verisimilitude is achieved by combining sufficiently accurate elements to give the impression of complete accuracy. By implementing the results of this research, designers can develop smaller replicas to be perceived as more extensive

An in-vitro evaluation of mechanical and esthetic properties of orthodontic sealants.

OBJECTIVE: To evaluate mechanical and esthetic Properties of two commercially available orthodontic sealants: Opal(®)Seal (OS) and L.E.D. Pro Seal (PS). MATERIALS AND METHODS: Discs of each sealant were prepared to test the following properties: Micro hardness, wear resistance and color stability. Samples were randomly selected after the wear test for SEM imaging to analyze surface morphology. RESULTS: OS was significantly harder than PS (P \u3c 0.001). PS was significantly more wear resistant than OS (P \u3c 0.05). PS showed a greater ∆E*ab (increased staining) when placed in wine or coffee showing a significant difference (P \u3c 0.05). SEM showed particle size, shape and distribution were different for PS and OS reflecting the pattern seen on wear surfaces. CONCLUSION: Both orthodontic sealants are beneficial for protecting enamel. However with better wear properties PS was superior in resisting mechanical stresses. OS was more color stable

Effects of Minoxidil Gel on Burn Wound Healing in Rats

Minoxidil has been reported to inhibit in-vitro fibroblast proliferation and lysyl hydroxylase activity, a key enzyme in collagen biosynthesis. These in-vitro effects proposed minoxidil to be a potential antifibrotic agent. The present study aimed to investigate the effects of minoxidil gel on wound healing procedure in a second-degree burn model in rats. Wistar rats were anesthetized and a second-degree burn was induced on the back of Wistar rats using a heated 2 cm diameter metal plate. Experimental groups received 2% or 5% topical minoxidil gel, dexpanthenol or sliver sulfadiazine. Histological parameters including collagen content, angiogenesis, number of preserved follicles and necrosis along with tensile strength of burn wound area were assessed on days 3, 7, 14 and 21 post-injury. Microscopic evaluation of specimens collected from sample animals were consistent and showed a second-degree burn. Main histological findings regarding minoxidil topical usage showed that collagen content and tensile strength of burned area did not differ between groups. However, minoxidil increased the number and diameter of blood vessels significantly compared with other groups. Although minoxidil improved the process of wound-healing, our results did not support the proposed idea of its usage as an antifibrotic agent. However, to reject its possible effects as an antifibrotic agent, more objective animal models should be developed and studied

Human germline heterozygous gain-of-function STAT6 variants cause severe allergic disease

STAT6 (signal transducer and activator of transcription 6) is a transcription factor that plays a central role in the pathophysiology of allergic inflammation. We have identified 16 patients from 10 families spanning three continents with a profound phenotype of early-life onset allergic immune dysregulation, widespread treatment-resistant atopic dermatitis, hypereosinophilia with esosinophilic gastrointestinal disease, asthma, elevated serum IgE, IgE-mediated food allergies, and anaphylaxis. The cases were either sporadic (seven kindreds) or followed an autosomal dominant inheritance pattern (three kindreds). All patients carried monoallelic rare variants in STAT6 and functional studies established their gain-of-function (GOF) phenotype with sustained STAT6 phosphorylation, increased STAT6 target gene expression, and TH2 skewing. Precision treatment with the anti-IL-4Rα antibody, dupilumab, was highly effective improving both clinical manifestations and immunological biomarkers. This study identifies heterozygous GOF variants in STAT6 as a novel autosomal dominant allergic disorder. We anticipate that our discovery of multiple kindreds with germline STAT6 GOF variants will facilitate the recognition of more affected individuals and the full definition of this new primary atopic disorder

Human germline heterozygous gain-of-function STAT6 variants cause severe allergic disease

STAT6 (signal transducer and activator of transcription 6) is a transcription factor that plays a central role in the pathophysiology of allergic inflammation. We have identified 16 patients from 10 families spanning three continents with a profound phenotype of early-life onset allergic immune dysregulation, widespread treatment-resistant atopic dermatitis, hypereosinophilia with esosinophilic gastrointestinal disease, asthma, elevated serum IgE, IgE-mediated food allergies, and anaphylaxis. The cases were either sporadic (seven kindreds) or followed an autosomal dominant inheritance pattern (three kindreds). All patients carried monoallelic rare variants in STAT6 and functional studies established their gain-of-function (GOF) phenotype with sustained STAT6 phosphorylation, increased STAT6 target gene expression, and TH2 skewing. Precision treatment with the anti-IL-4Rα antibody, dupilumab, was highly effective improving both clinical manifestations and immunological biomarkers. This study identifies heterozygous GOF variants in STAT6 as a novel autosomal dominant allergic disorder. We anticipate that our discovery of multiple kindreds with germline STAT6 GOF variants will facilitate the recognition of more affected individuals and the full definition of this new primary atopic disorder