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Nanotechnology has brought a variety of new possibilities into biological discovery and clinical practice. In particular, nano-scaled carriers have revolutionalized drug delivery, allowing for therapeutic agents to be selectively targeted on an organ, tissue and cell specific level, also minimizing exposure of healthy tissue to drugs. In this review we discuss and analyze three issues, which are considered to be at the core of nano-scaled drug delivery systems, namely functionalization of nanocarriers, delivery to target organs and in vivo imaging. The latest developments on highly specific conjugation strategies that are used to attach biomolecules to the surface of nanoparticles (NP) are first reviewed. Besides drug carrying capabilities, the functionalization of nanocarriers also facilitate their transport to primary target organs. We highlight the leading advantage of nanocarriers, i.e. their ability to cross the blood-brain barrier (BBB), a tightly packed layer of endothelial cells surrounding the brain that prevents high-molecular weight molecules from entering the brain. The BBB has several transport molecules such as growth factors, insulin and transferrin that can potentially increase the efficiency and kinetics of brain-targeting nanocarriers. Potential treatments for common neurological disorders, such as stroke, tumours and Alzheimer's, are therefore a much sought-after application of nanomedicine. Likewise any other drug delivery system, a number of parameters need to be registered once functionalized NPs are administered, for instance their efficiency in organ-selective targeting, bioaccumulation and excretion. Finally, direct in vivo imaging of nanomaterials is an exciting recent field that can provide real-time tracking of those nanocarriers. We review a range of systems suitable for in vivo imaging and monitoring of drug delivery, with an emphasis on most recently introduced molecular imaging modalities based on optical and hybrid contrast, such as fluorescent protein tomography and multispectral optoacoustic tomography. Overall, great potential is foreseen for nanocarriers in medical diagnostics, therapeutics and molecular targeting. A proposed roadmap for ongoing and future research directions is therefore discussed in detail with emphasis on the development of novel approaches for functionalization, targeting and imaging of nano-based drug delivery systems, a cutting-edge technology poised to change the ways medicine is administered.

The research community has considered in the past the application of Artificial Intelligence (AI) techniques to control and operate networks. A notable example is the Knowledge Plane proposed by D.Clark et al. However, such techniques have not been extensively prototyped or deployed in the field yet. In this paper, we explore the reasons for the lack of adoption and posit that the rise of two recent paradigms: Software-Defined Networking (SDN) and Network Analytics (NA), will facilitate the adoption of AI techniques in the context of network operation and control. We describe a new paradigm that accommodates and exploits SDN, NA and AI, and provide use cases that illustrate its applicability and benefits. We also present simple experimental results that support its feasibility. We refer to this new paradigm as Knowledge-Defined Networking (KDN).Comment: 8 pages, 22 references, 6 figures and 1 tabl

In this study, we quantitatively analyzed the affinity of cell adhesion to aligned nanofibers composed of composites of poly(glycolic acid) (PGA) and collagen. Electrospun composite fibers were fabricated at various PGA/collagen weight mixing ratio (7, 18, 40, 67, and 86%) to generate fibers that ranged in diameter from 10 mum to 500 nm. Scanning electron microscopy (SEM) observation revealed that the PGA/collagen fibers were long and uniformly aligned, irrespective of the PGA/collagen weight mixing ratio. In addition, it was observed that a significantly higher number of NIH3T3 fibroblasts adhered to nanofibers with smaller diameters in comparison to fibers with larger diameters. The highest affinity of cell adhesion was observed in the PGA/collagen fibers with diameter of 500 nm and PGA/collagen weight mixing ratio of 40%. Furthermore, the adherent cells were more elongated on fibers with smaller diameters. Thus, based on the results here, PGA/collagen composite fibers are suitable for tissue culture studies and provide an attractive material for tissue engineering applications.

Early detection of cancer greatly increases the chances of a simpler and more effective treatment. Traditional imaging techniques are often limited by shallow penetration, low sensitivity, low specificity, poor spatial resolution or the use of ionizing radiation. Hybrid modalities, like optoacoustic imaging, an emerging molecular imaging modality, contribute to improving most of these limitations. However, this imaging method is hindered by relatively low signal contrast. Here, gold nanoprisms (AuNPrs) are used as signal amplifiers in multispectral optoacoustic tomography (MSOT) to visualize gastrointestinal cancer. PEGylated AuNPrs are successfully internalized by HT-29 gastrointestinal cancer cells in vitro. Moreover, the particles show good biocompatibility and exhibit a surface plasmon band centered at 830 nm, a suitable wavelength for optoacoustic imaging purposes. These findings extend well to an in vivo setting, in which mice are injected with PEGylated AuNPrs in order to visualize tumor angiogenesis in gastrointestinal cancer cells. Overall, both our in vitro and in vivo results show that PEGylated AuNPrs have the capacity to penetrate tumors and provide a high-resolution signal amplifier for optoacoustic imaging. The combination of PEGylated AuNPrs and MSOT represents a significant advance for the in vivo imaging of cancers.