Development of a novel sample reuse approach to measure the impact of lean meat, bone and adipose tissue on the development of volatiles in vacuum-packed chilled lamb stored at 2 °C for 15 days.

The impact of different ratios of lean meat, adipose tissue (fat) and bone on the volatile organic compound (VOC) profile of vacuum-packed (VP) lamb stored at 2 °C for up to 15 days was investigated using two sampling approaches. VOC development in individual samples was followed over time using either a traditional sampling regime where replicate samples were sampled (single-use) at a given time or a novel approach where replicate samples were resampled (reuse) over time. VOCs present in the headspace of the packaged samples were detected using proton-transfer-reaction mass spectrometry (PTR-MS) with complementary solid phase micro-extraction gas chromatography-mass spectrometry (SPME-GC-MS) analysis on a subset of samples. Bacteria numbers were determined using standard microbiological methods. Meat packaged with 20% added adipose tissue contained slightly higher numbers of bacteria at the start of the trial with correspondingly higher VOC levels compared to lean meat alone. Storage time (as a proxy for microbial numbers) was the main driver for VOC production. Differences between the reuse and the single-use sample sets were minimal, suggesting that resampling of VP lamb samples may be a useful approach to study the development of low frequency spoilage patterns over time.

Effect of Opalescence(®) bleaching gels on the elution of bulk-fill composite components.

OBJECTIVES: Bleaching treatments can affect release of components from conventional composites. In this continuing study the influence of two different bleaching gels on the elution of bulk-fill composite components was investigated. METHODS: The composites Tetric EvoCeram(®) Bulk Fill, QuiXFil™ and X-tra fil were treated with the bleaching gels Opalescence PF 15% (PF 15%) for 5 h and PF 35% (PF 35%) for 30 min and then stored in methanol and water for 24 h and 7 d. The eluates were analyzed by gas chromatography/mass spectrometry (GC/MS). Unbleached specimens were used as control group. RESULTS: A total of 7 different elutable substances have been identified from the investigated composites after bleaching-treatment. Three of them were methacrylates: 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA) and trimethylolpropane trimethacrylate (TMPTMA). Compared to the unbleached controls an increase in elution after PF 15%-treatment of following compounds was found: HEMA (Tetric EvoCeram(®) Bulk Fill), TEGDMA (QuiXFil™, X-tra fil) and 4-N,N-dimethylaminobenzoic acid butyl ethoxy ester (DMABEE) (Tetric EvoCeram(®) Bulk Fill, QuiXFil™, X-tra fil). Following compounds showed a reduction in elution after PF 35%-treatment compared to controls: TEGDMA (QuiXFil™) and DMABEE (Tetric EvoCeram(®) Bulk Fill). The highest concentration of HEMA was 0.22 mmol/l (Tetric EvoCeram(®) Bulk Fill, methanol, 7 d, PF 15%), the highest concentration of TEGDMA was 0.3 mmol/l (X-tra fil, water, 7 d, PF 15%) and the highest concentration of DMABEE was 0.05 mmol/l (QuiXFil™, water, 7 d, PF 35%). SIGNIFICANCE: PF 15% and PF 35% can lead to reduced and/or increased elution of some bulk-fill components, compared to unbleached bulk-fill composites.

Effect of Opalescence® bleaching gels on the elution of dental composite components.

OBJECTIVES: Bleaching treatments can affect on the polymer network of dental composites. This study was performed to evaluate the influence of different bleaching treatments on the elution of composite components. METHODS: The composites Tetric EvoCeram(®), CLEARFIL™ AP-X, Tetric EvoFlow(®), Filtek™ Supreme XT, Ceram X(®) mono+, Admira and Filtek™ Silorane were treated with the bleaching gels Opalescence PF 15% (PF 15%) for 5h and PF 35% (PF 35%) for 30 min and then stored in methanol and water for 24h and 7 d. The eluates were analyzed by gas chromatography/mass spectrometry (GC/MS). Unbleached specimens were used as control group. RESULTS: A total of 16 different elutable substances have been identified from the investigated composites after bleaching-treatment. Six of them were methacrylates: 1,10-decandioldimethacrylate (DDDMA), 1,12-dodekandioldimethacrylate (DODDMA), ethylenglycoldimethacrylate (EGDMA), 2-hydroxyethylmethacrylate (HEMA), triethylenglycoldimethacrylate (TEGDMA) and urethandimethacrylate (UDMA). Compared with the unbleached controls the composites Tetric EvoCeram(®), CLEARFIL™ AP-X and Tetric EvoFlow(®) showed a reduced elution of UDMA, TEGDMA and HEMA after bleaching-treatment. Compared with the unbleached controls an increase elution of UDMA, DMABEE, BPA and TEGDMA for the composites Filtek™ Supreme XT, Ceram X(®) mono+, Admira and Filtek™ Silorane after bleaching-treatment has been detected. The highest concentration of UDMA was 0.01 mmol/l (Tetric EvoCeram(®), water, 24h, controls), the highest concentration of TEGDMA was 0.28 mmol/l (CLEARFIL™ AP-X, water, 7 d, controls), the highest concentration of HEMA was 0.74 mmol/l (Tetric EvoFlow(®), methanol, 7 d, PF 35%), the highest concentration of DMABEE was 0.10 mmol/l (Ceram X(®) mono+, water, 7 d, PF 35%) and the highest concentration of BPA was 0.01 mmol/l (Admira, methanol, 7 d, controls). SIGNIFICANCE: Bleaching treatments can lead to a reduced or an increased elution of substances from the dental composites.

The elution and breakdown behavior of constituents from various light-cured composites.

OBJECTIVES: Constituents of dental composites can be released from dental fillings after polymerization. The aim of this study was to examine the time-related elution and breakdown of separable constituents of polymerized composites using deuterated solvents. METHOD: Elution and breakdown of constituents were investigated with deuterated solvents methanol and water by gas chromatography/mass spectrometry of following composites for 180 days: Filtek™ Supreme XT, Filtek™ Supreme XT Flow, Tetric Ceram(®), Tetric Flow(®), Grandio(®), Grandio(®) Flow. RESULTS: Within 180 days no compounds were formed as the products of breakdown. 19 compounds were identified as elution products: Bis-EMA, TEGDMA, DDDMA, EGDMA, MAA, BPA, CQ, HQME, DMABEE, CSA, BL, TEG, BHT, TINP, TPP, TPSB, DEDHTP, DCHP, ß-PHEA. The highest concentration of Bis-EMA was measured for Tetric Flow(®) in deuterated methanol on day 90 at 36.993mmol/l and in deuterated water also on day 90 at 0.031mmol/l. The highest TEGDMA concentrations were measured for Grandio(®) Flow in deuterated methanol on day 60 at 1.322mmol/l and for Filtek™ Supreme XT Flow in deuterated water on day 3 at 0.689mmol/l. The highest BPA concentration was measured for Tetric Flow(®) in deuterated methanol on day 90 at 1.469mmol/l. The highest BPA concentration was measured for Grandio(®) in deuterated water on day 180 at 0.007mmol/l. Significance Examination of time-related elution indicates that various elution products (e.g. Bis-EMA, BPA) were only released in small quantities during the first 90 days, but in high quantities between day 90 and day 180.

Functional outcome in patients with advanced head and neck cancer: surgery and reconstruction with free flaps versus primary radiochemotherapy.

The objective was to compare functional outcome in patients with advanced head and neck cancer (HNC) treated with (a) surgical resection and reconstruction with microvascular free flaps (MVFF) followed by radiochemotherapy versus (b) primary radiochemotherapy (RCT) on the basis of the International Classification of Functioning, Disability and Health (ICF) from WHO. This was a cross-sectional, multi-institutional study. The outcome measures included ICF Core Sets for HNC, the EORTC-QLQ, modules c30 + hn35 and the University of Washington-Quality of life Questionnaire (UW-QOL). Analyses included descriptive statistics, ranking exercises, and regression analyses in a cumulative logit model; 27 patients were treated with MVFF and 22 with RCT. Global Quality of life scores suggested a slightly better functional outcome for the surgical approach. The majority of ICF categories (81/93, 87%) did not show a difference in functional outcome between the two treatment approaches. In the remaining 12 ICF categories, n = 3 body structures were more affected in the MVFF group, while n = 3 body functions, and n = 6 activities/participations were more problematic in the RCT group. This included oral swallowing and weight maintenance functions as well as social relationships, acquiring a job, and economic self-sufficiency. In addition, nine contextual environmental factors were more relevant to the RCT group. Both treatment approaches seemed appropriate to advanced HNC from the perspective of functional outcome. The influence of treatment modalities on the social and economic lives of cancer survivors needs to be explored further. In order to guide rehabilitation according to patients' needs, the ICF offers a multidimensional view comprising body structures, body functions, and activities and participation in life.