29 research outputs found

    Analysis of radiation-induced cell death in head and neck squamous cell carcinoma and rat liver maintained in microfluidic devices

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    Objective The aim of this study was to investigate how head and neck squamous cell carcinoma (HNSCC) tissue biopsies maintained in a pseudo in vivo environment within a bespoke microfluidic device respond to radiation treatment. Study Design Feasibility study. Setting Tertiary referral center. Subjects and Methods Thirty-five patients with HNSCC were recruited, and liver tissue from 5 Wistar rats was obtained. A microfluidic device was used to maintain the tissue biopsy samples in a viable state. Rat liver was used to optimize the methodology. HNSCC was obtained from patients with T1-T3 laryngeal or oropharyngeal SCC; N1-N2 metastatic cervical lymph nodes were also obtained. Irradiation consisted of single doses of between 2 Gy and 40 Gy and a fractionated course of 5×2 Gy. Cell death was assessed in the tissue effluent using the soluble markers lactate dehydrogenase (LDH) and cytochrome c and in the tissue by immunohistochemical detection of cleaved cytokeratin18 (M30 antibody). Results A significant surge in LDH release was demonstrated in the rat liver after a single dose of 20 Gy; in HNSCC, it was seen after 40 Gy compared with the control. There was no significant difference in cytochrome c release after 5 Gy or 10 Gy. M30 demonstrated a dose-dependent increase in apoptotic index for a given increase in single-dose radiotherapy. There was a significant increase in apoptotic index between 1×2 Gy and 5×2 Gy. Conclusion M30 is a superior method compared with soluble markers in detecting low-dose radiation-induced cell death. This microfluidic technique can be used to assess radiation-induced cell death in HNSCC and therefore has the potential to be used to predict radiation response

    Single-Dose Intravenous Toxicity Study of IRDye 800CW in Sprague-Dawley Rats

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    Objective: Fluorophore-labeled contrast imaging agents are moving toward clinical use for a number of applications. The near-infrared dye IRDye 800CW is frequently used in its N-hydroxysuccinamide (NHS) ester form for labeling these agents. Following conjugation or breakdown of a labeled ligand, excess NHS ester is converted to the carboxylate form. To prepare for clinical use as a near-infrared fluorophore, a toxicity study was conducted on IRDye 800CW carboxylate. Methods: Male and female Sprague–Dawley rats were given a single intravenous or intradermal administration of IRDye 800CW carboxylate; Indocyanine Green was used as a comparative control. Animals were injected with varying doses of the test and control articles and observed for up to 14 days. Clinical chemistry, hematological, and pharmacokinetic analyses were performed on subgroups of animals. Organs were analyzed for content of the test article. Tissues were analyzed microscopically for pathological changes. Results: Based on hematologic, clinical chemistry, and histopathologic evaluation, single administration of IRDye 800CW carboxylate intravenously at dose levels of 1, 5, and 20 mg/kg or 20 mg/kg intradermally produced no pathological evidence of toxicity. Conclusion: A dose of 20 mg/kg was identified as the no observed adverse effect level following IV or ID routes of administration of IRDye 800CW

    Comparative review of human and canine osteosarcoma: morphology, epidemiology, prognosis, treatment and genetics

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    Osteosarcoma (OSA) is a rare cancer in people. However OSA incidence rates in dogs are 27 times higher than in people. Prognosis in both species is poor, with five year osteosarcoma survival rates in people not having improved in decades. For dogs, one year survival rates are only around ~45%. Improved and novel treatment regimens are urgently required to improve survival in both humans and dogs with OSA. Utilising information from genetic studies could assist in this in both species, with the higher incidence rates in dogs contributing to the dog population being a good model of human disease. This review compares the clinical characteristics, gross morphology and histopathology, aetiology, epidemiology, and genetics of canine and human osteosarcoma. Finally, the current position of canine osteosarcoma genetic research is discussed and areas for additional work within the canine population are identified

    Assessment of peri- and postoperative complications and Karnofsky-performance status in head and neck cancer patients after radiation or chemoradiation that underwent surgery with regional or free-flap reconstruction for salvage, palliation, or to improve function

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    <p>Abstract</p> <p>Background</p> <p>Surgery after (chemo)radiation (RCTX/RTX) is felt to be plagued with a high incidence of wound healing complications reported to be as high as 70%. The additional use of vascularized flaps may help to decrease this high rate of complications. Therefore, we examined within a retrospective single-institutional study the peri--and postoperative complications in patients who underwent surgery for salvage, palliation or functional rehabilitation after (chemo)radiation with regional and free flaps. As a second study end point the Karnofsky performance status (KPS) was determined preoperatively and 3 months postoperatively to assess the impact of such extensive procedures on the overall performance status of this heavily pretreated patient population.</p> <p>Findings</p> <p>21 patients were treated between 2005 and 2010 in a single institution (17 male, 4 female) for salvage (10/21), palliation (4/21), or functional rehabilitation (7/21). Overall 23 flaps were performed of which 8 were free flaps. Major recipient site complications were observed in only 4 pts. (19%) (1 postoperative haemorrhage, 1 partial flap loss, 2 fistulas) and major donor site complications in 1 pt (wound dehiscence). Also 2 minor donor site complications were observed. The overall complication rate was 33%. There was no free flap loss. Assessment of pre- and postoperative KPS revealed improvement in 13 out of 21 patients (62%). A decline of KPS was noted in only one patient.</p> <p>Conclusions</p> <p>We conclude that within this (chemo)radiated patient population surgical interventions for salvage, palliation or improve function can be safely performed once vascularised grafts are used.</p
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