2,258 research outputs found
Transmission of viruses via our microbiomes.
BackgroundBacteria inhabiting the human body have important roles in a number of physiological processes and are known to be shared amongst genetically-related individuals. Far less is known about viruses inhabiting the human body, but their ecology suggests they may be shared between close contacts.ResultsHere, we report the ecology of viruses in the guts and mouths of a cohort and demonstrate that substantial numbers of gut and oral viruses were shared amongst genetically unrelated, cohabitating individuals. Most of these viruses were bacteriophages, and each individual had distinct oral and gut viral ecology from their housemates despite the fact that some of their bacteriophages were shared. The distribution of bacteriophages over time within households indicated that they were frequently transmitted between the microbiomes of household contacts.ConclusionsBecause bacteriophages may shape human oral and gut bacterial ecology, their transmission to household contacts suggests they could have substantial roles in shaping the microbiota within a household
Image-guided fluorescence tomography in head & neck surgical models
Clinical indications for fluorescence-guided surgery continue to expand, and are being spurred by the rapid development of new agents that improve biological targeting.1 There is a corresponding need to develop imaging systems that quantify fluorescence - not only at the tissue surface, but at depth. We have recently described an image-guided fluorescence tomography system that leverages geometric data from intraoperative cone-beam CT and surgical navigation,2 and builds on finite-element method software (NIRFAST) for diffuse optical tomography (DOT).3 DOT systems have most commonly been used for sub-surface inclusions buried within tissue (e.g., breast and neurological tumors). Here, we focus on inclusion models relevant to tumors infiltrating from the mucosal surface (an âicebergâ model), as is most often the case in head and neck cancer, where over 85% of tumors are squamous cell carcinoma.4 This work presents results from simulations, tissue-simulating anatomical phantoms, and animal studies involving infiltrative tumor models. The objective is to characterize system performance across a range of inclusion diameters, depths, and optical properties. For example, Fig. 1 shows a fluorescence reconstruction of a simulated tonsil tumor in an oral cavity phantom. Future clinical studies are necessary to assess in vivo performance and intraoperative workflow.
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Performance of case-control rare copy number variation annotation in classification of autism
Enhanced uptake of nanoparticle drug carriers via a thermoresponsive shell enhances cytotoxicity in a cancer cell line
Polymer particles consisting of a biodegradable poly[lactide-co-glycolide] (PLGA) core and a thermoresponsive shell have been formulated to encapsulate the dye rhodamine 6G and the potent cytotoxic drug paclitaxel. Cellular uptake of these particles is significantly enhanced above the thermal transition temperature (TTT) of the polymer shells in the human breast carcinoma cell line MCF-7 as determined by flow cytometry and fluorescence microscopy. Paclitaxel-loaded particles display reduced and enhanced cytotoxicity below and above the TTT respectively compared to unencapsulated drug. The data suggests a potential route to enhanced anti-cancer efficacy through temperature-mediated cell targeting.© The Royal Society of Chemistry 2013
Laser surface treatment of polyamide and NiTi alloy and the effects on mesenchymal stem cell response
Mesenchymal stem cells (MSCs) are known to play important roles in development, post-natal growth, repair, and regeneration of mesenchymal tissues. What is more, surface treatments are widely reported to affect the biomimetic nature of materials. This paper will detail, discuss and compare laser surface treatment of polyamide (Polyamide 6,6), using a 60 W CO2 laser, and NiTi alloy, using a 100 W fiber laser, and the effects of these treatments on mesenchymal stem cell response. The surface morphology and composition of the polyamide and NiTi alloy were studied by scanning electron microscopy (SEM) and X-ray photoemission spectroscopy (XPS), respectively. MSC cell morphology cell counting and viability measurements were done by employing a haemocytometer and MTT colorimetric assay. The success of enhanced adhesion and spreading of the MSCs on each of the laser surface treated samples, when compared to as-received samples, is evidenced in this work
Suitability versus fidelity for rating single-photon guns
The creation of specified quantum states is important for most, if not all,
applications in quantum computation and communication. The quality of the state
preparation is therefore an essential ingredient in any assessment of a
quantum-state gun. We show that the fidelity, under the standard definitions is
not sufficient to assess quantum sources, and we propose a new measure of
suitability that necessarily depends on the application for the source. We
consider the performance of single-photon guns in the context of quantum key
distribution (QKD) and linear optical quantum computation. Single-photon
sources for QKD need radically different properties than sources for quantum
computing. Furthermore, the suitability for single-photon guns is discussed
explicitly in terms of experimentally accessible criteria.Comment: 4 pages, 2 figures Revised per referee suggestion
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