11 research outputs found

    Knee osteoarthritis and periarticular structure quantified by ultrasound. A case-control study

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    Background Assessment of pain and physical function is complex in patients with knee osteoarthritis (OA), as standard criteria are lacking.A previous study examining correlations between functional capacity and pain (WOMAC) and anthropometric characteristics and periarticular knee structure (quantified by ultrasound imaging) in females with knee OA found increased quadriceps muscle density was associated with higher functional disability and pain scores, suggesting that not only joint wear and symptom severity are involved and more objective measures are necessary..

    Potential of gas chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry for screening and quantification of hexabromocyclododecane

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    A fast method for the screening and quantification of hexabromocyclododecane (sum of all isomers) by gas chromatography using a triple quadrupole mass spectrometer with atmospheric pressure chemical ionization (GC-APCI-QqQ) is proposed. This novel procedure makes use of the soft atmospheric pressure chemical ionization source, which results in less fragmentation of the analyte than by conventional electron impact (EI) and chemical ionization (CI) sources, favoring the formation of the [M - Br] ion and, thus, enhancing sensitivity and selectivity. Detection was based on the consecutive loses of HBr from the [M - Br] ion to form the specific [M - HBr] and [M - HBr] ions, which were selected as quantitation (Q) and qualification (q) transitions, respectively. Parameters affecting ionization and MS/MS detection were studied. Method performance was also evaluated; calibration curves were found linear from 1 pg/μL to 100 pg/μL for the total HBCD concentration; instrumental detection limit was estimated to be 0.10 pg/μL; repeatability and reproducibility, expressed as relative standard deviation, were better than 7 % in both cases. The application to different real samples [polyurethane foam disks (PUFs), food, and marine samples] pointed out a rapid way to identify and allow quantification of this compound together with a number of polybrominated diphenyl ethers (BDE congeners 28, 47, 66, 85, 99, 100, 153, 154, 183, 184, 191, 196, 197, and 209) and two other novel brominated flame retardants [i.e., decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE)] because of their presence in the same fraction when performing the usual sample treatment.The authors acknowledge the financial support of Generalitat Valenciana, (research group of excellence PROMETEO/ 2009/054 and PROMETEO II 2014/023 and Collaborative Research on Environment and Food-Safety (ISIC/2012/016)). The authors also acknowledge the financial support given by the Spanish Ministry of Economy and Competitiveness and European funding from FEDER program(projectAGL2012-37201) and (UNEP). The authors are grateful to Dr. José Luis Acuña and Mrs. Sonia Romero for providing the marine samples.Peer Reviewe

    Analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans in stack gas emissions by gas chromatography-atmospheric pressure chemical ionization-triple-quadrupole mass spectrometry

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    A gas chromatography coupled to triple-quadrupole mass spectrometry (GC-(QqQ)MS/MS) including a soft-ionization through an atmospheric pressure chemical ionization (APCI) source based method was compared with the high resolution mass spectrometry (HRMS) standard reference method EN1948, for the analysis of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in stack gas emissions. The stack emission samples were collected, both, by manual method sampling (from 6 to 8 h) and by long-term sampling systems (sampling time of several weeks). This work presents the first comparison of GC-(QqQ)MS/MS with APCI source with the European Standard EN1948 technique for stack gas emissions. Sample concentrations ranged from 0.5 to 596 pg I-TEQ/Nm3. Comparative results in all investigated samples showed relative errors that were within ±15%. These results make GC-(QqQ)MS/MS with APCI suitable for the quantitative analysis of dioxins in the studied samples and create a real alternative tool to the reference sector GC-HRMS instruments

    Knee osteoarthritis and periarticular structure quantified by ultrasound. A case-control study

    No full text
    Background Assessment of pain and physical function is complex in patients with knee osteoarthritis (OA), as standard criteria are lacking.A previous study examining correlations between functional capacity and pain (WOMAC) and anthropometric characteristics and periarticular knee structure (quantified by ultrasound imaging) in females with knee OA found increased quadriceps muscle density was associated with higher functional disability and pain scores, suggesting that not only joint wear and symptom severity are involved and more objective measures are necessary..
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