Safety Concern between Autologous Fat Graft, Mesenchymal Stem Cell and Osteosarcoma Recurrence

Background: Osteosarcoma is the most common malignant primary bone tumour in young adult treated by neo adjuvant chemotherapy, surgical tumor removal and adjuvant multidrug chemotherapy. For correction of soft tissue defect consecutive to surgery and/or tumor treatment, autologous fat graft has been proposed in plastic and reconstructive surgery. Principal Findings: We report here a case of a late local recurrence of osteosarcoma which occurred 13 years after the initial pathology and 18 months after a lipofilling procedure. Because such recurrence was highly unexpected, we investigated the possible relationship of tumor growth with fat injections and with mesenchymal stem/stromal cell like cells which are largely found in fatty tissue. Results obtained in osteosarcoma pre-clinical models show that fat grafts or progenitor cells promoted tumor growth. Significance: These observations and results raise the question of whether autologous fat grafting is a safe reconstructive procedure in a known post neoplasic context

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Photograph used for a story in the Daily Oklahoman newspaper. Caption: "OU's Mike Gomez tightens his grip on OSU's Brian Stevens during their 126-pound bout Thursday night at Gallagher Hall.

Modeling the short-term unfairness of ieee 802.11 in presence of hidden terminals

IEEE 802.11 exhibits both short-term and long-term unfairness [15]. The short-term fairness automatically gives rise to long-term fairness, but not vice versa [11]. When we thoroughly investigated a simple scenario with hidden terminals, we found it to be unfair on the short-term basis, though it provides fair access on a long-term basis. It implies that the protocol cannot be used to provide fair access for delay sensitive traffic even in a simple scenario. In this paper, we analyze the short-term behavior using the embedded-Markov chain method to answer the following two questions: (i) once a node gets control of the medium, what is the average number of packets this node can transmit consecutively without experiencing any collision, (ii) once a node loses its control of the medium, what is the average time the node has to wait before it gets control of the medium again. The first question reflects on how long a node can capture the medium, whereas the second question reflects on how long a node may be starved. The analytical model is validated by the simulation results. Our work is distinct from most of the work published in the literature in two aspects: we focus on the short-term behavior rather than the long-term, and the analytical method is adopted for the study. Keywords: IEEE 802.11, Hidden-terminal, Short-term Fairness, Embedded Markov Chain,

WING/WORLD: An Open Experimental Toolkit for the Design and Deployment of IEEE 802.11-Based Wireless Mesh Networks Testbeds

Wireless Mesh Networks represent an interesting instance of light-infrastructure wireless networks. Due to their flexibility and resiliency to network failures, wireless mesh networks are particularly suitable for incremental and rapid deployments of wireless access networks in both metropolitan and rural areas. This paper illustrates the design and development of an open toolkit aimed at supporting the design of different solutions for wireless mesh networking by enabling real evaluation, validation, and demonstration. The resulting testbed is based on off-the-shelf hardware components and open-source software and is focused on IEEE 802.11 commodity devices. The software toolkit is based on an “open” philosophy and aims at providing the scientific community with a tool for effective and reproducible performance analysis of WMNs. The paper describes the architecture of the toolkit, and its core functionalities, as well as its potential evolutions