A novel radiographic scoring system for growth abnormalities and structural change in children with juvenile idiopathic arthritis of the hip

Background: Approximately 20\u201350% of children with juvenile idiopathic arthritis (JIA) have hip involvement within 6 years of diagnosis. Scoring systems for hip-related radiographic changes are lacking. Objective: To examine precision of potential radiographic variables and to suggest a scoring system. Materials and methods: We reviewed a set of 75 pelvic radiographs from 75 children with JIA hip involvement across two European centres. We assessed findings of (1) destructive change and (2) growth abnormality, according to a pre-defined scoring system. All radiographs were scored independently by two sets of radiologists. One set scored the radiographs a second time. We used kappa statistics to rate inter- and intra-observer variability. Results: Assessment of erosions of the femoral head, femoral neck and the acetabulum showed moderate to good agreement for the same reader (kappa of 0.5\u20130.8). The inter-reader agreement was, however, low (kappa of 0.1\u20130.3). There was moderate to high agreement for the assessment of femoral head flattening (kappa of 0.6\u20130.7 for the same reader, 0.3\u20130.7 between readers). Joint space narrowing showed moderate to high agreement both within and between observers (kappa of 0.4\u20130.8). Femoral neck length and width measurements, the centrum\u2013collum\u2013diaphysis angle, and trochanteric\u2013femoral head lengths were relatively precise, with 95% limits of agreement within 10\u201315% of the observer average. Conclusion: Several radiographic variables of destructive and growth abnormalities in children with hip JIA have reasonable reproducibility. We suggest that future studies on clinical validity focus on assessing only reproducible radiographic variables

Modular Synthesis of Functional Nanoscale Coordination Polymers

The coordination-directed assembly of metal ions and organic bridging ligands has afforded a variety of bulk-scale hybrid materials with promising characteristics for a number of practical applications, such as gas storage and heterogeneous catalysis. Recently, so-called coordination polymers have emerged as a new class of hybrid nanomaterials. Herein, we highlight advances in the syntheses of both amorphous and crystalline nanoscale coordination polymers. We also illustrate how scaling down these materials to the nano-regime has enabled their use in a broad range of applications including catalysis, spin-crossover, templating, biosensing, biomedical imaging, and anticancer drug delivery. These results underscore the exciting opportunities of developing next-generation functional nanomaterials based on molecular components

Surface Modification and Functionalization of Nanoscale Metal-Organic Frameworks for Controlled Release and Luminescence Sensing

We describe in this paper a general method for synthesizing a new class of nanocomposites with a nanoscale metal-organic framework (NMOF) core and a silica shell. Silica shells of variable thickness were deposited on the NMOFs that had been surface-modified with polyvinylpyrrolidone (PVP) using a sol-gel procedure. The NMOF core of the nanocomposite could be completely removed (via dissolution) at low pH to afford hollow silica shells with varied thickness and aspect ratios. We also showed that the silica shell of such nanocomposites significantly stabilized the NMOF core against dissolution, thus demonstrating the ability to control the release of metal constituents from such silica-coated NMOFs. The silica shell was further functionalized with a silylated Tb-EDTA monoamide derivative for the luminescence sensing of dipicolinic acid (DPA), which is a major constituent of many pathogenic spore-forming bacteria. Owing to the tunability of NMOF composition and morphology, the present approach should allow for the synthesis of not only interesting nanoshells that are not accessible with presently available templates but also novel core-shell hybrid nanostructures for future imaging, sensing, and drug delivery applications

Nanoscale Metal−Organic Frameworks as Potential Multimodal Contrast Enhancing Agents

Nanoscale metal-organic frameworks (NMOFs) based on Gd3+ centers and benzenedicarboxylate and benzenetricarboxylate bridging ligands were synthesized using reverse microemulsions and characterized using SEM, PXRD, and TGA. These NMOFs exhibit extraordinarily large R1 and R2 relaxivities because of the presence of up to tens of millions of Gd3+ centers in each nanoparticle and are thus efficient T1 and T2 contrast agents for MRI. The NMOFs can also be made highly luminescent by doping with Eu3+ or Tb3+ centers. The results from this work suggest that NMOFs can be used as potential contrast agents for multimodal imaging

Self-Assembled Hybrid Nanoparticles for Cancer-Specific Multimodal Imaging

A layer-by-layer (LbL) polyelectrolyte deposition strategy is used to prepare multifunctional nanoparticles (MFNPs) with multimodal imaging capabilities. Alternating treatment of hybrid silica nanoparticles (NP0) containing a luminescent [Ru(bpy)3]Cl2 core and anionic monolayer coating of the Gd−(siloxylpropyl)diethylenetriamine tetraacetate (Gd−DTTA) complex with cationic Gd(III)−DOTA oligomer 1 and anionic poly(styrene sulfonate) (PSS) led to the deposition of multilayers of 1 and PSS via electrostatic interactions. This LbL deposition technique offers a superb strategy for the assembly of hybrid nanoparticles with imbedded luminophores and very high MR relaxivities. The PSS-terminated multilayered nanoparticles can be noncovalently functionalized with targeting peptides that carry positive charges under physiological conditions via electrostatic interactions to lead to cancer-specific MFNPs for optical and MR imaging of HT-29 human colon cancer cells. The generality of this approach should allow the de..

A new method to position and functionalize metal-organic framework crystals

With controlled nanometre-sized pores and surface areas of thousands of square metres per gram, metal-organic frameworks (MOFs) may have an integral role in future catalysis, filtration and sensing applications. In general, for MOF-based device fabrication, well-organized or patterned MOF growth is required, and thus conventional synthetic routes are not suitable. Moreover, to expand their applicability, the introduction of additional functionality into MOFs is desirable. Here, we explore the use of nanostructured poly-hydrate zinc phosphate (α-hopeite) microparticles as nucleation seeds for MOFs that simultaneously address all these issues. Affording spatial control of nucleation and significantly accelerating MOF growth, these α-hopeite microparticles are found to act as nucleation agents both in solution and on solid surfaces. In addition, the introduction of functional nanoparticles (metallic, semiconducting, polymeric) into these nucleating seeds translates directly to the fabrication of functional MOFs suitable for molecular size-selective applications

Multifunctional Magnetic-fluorescent Nanocomposites for Biomedical Applications

Nanotechnology is a fast-growing area, involving the fabrication and use of nano-sized materials and devices. Various nanocomposite materials play a number of important roles in modern science and technology. Magnetic and fluorescent inorganic nanoparticles are of particular importance due to their broad range of potential applications. It is expected that the combination of magnetic and fluorescent properties in one nanocomposite would enable the engineering of unique multifunctional nanoscale devices, which could be manipulated using external magnetic fields. The aim of this review is to present an overview of bimodal “two-in-one” magnetic-fluorescent nanocomposite materials which combine both magnetic and fluorescent properties in one entity, in particular those with potential applications in biotechnology and nanomedicine. There is a great necessity for the development of these multifunctional nanocomposites, but there are some difficulties and challenges to overcome in their fabrication such as quenching of the fluorescent entity by the magnetic core. Fluorescent-magnetic nanocomposites include a variety of materials including silica-based, dye-functionalised magnetic nanoparticles and quantum dots-magnetic nanoparticle composites. The classification and main synthesis strategies, along with approaches for the fabrication of fluorescent-magnetic nanocomposites, are considered. The current and potential biomedical uses, including biological imaging, cell tracking, magnetic bioseparation, nanomedicine and bio- and chemo-sensoring, of magnetic-fluorescent nanocomposites are also discussed