404 research outputs found

    Monitoring Response to Radiotherapy in Human Squamous Cell Cancer Bearing Nude Mice: Comparison of 2′-deoxy-2′-[18F]fluoro-d-glucose (FDG) and 3′-[18F]fluoro-3′-deoxythymidine (FLT)

    Get PDF
    Objective: The uptake of 3′-[18F]fluoro-3′- deoxythymidine (FLT), a proliferation marker, was measured before and during fractionated radiotherapy to evaluate the potential of FLT-positron emission tomography (PET) imaging as an indicator of tumor response compared to 2′-deoxy-2′-[18F]fluoro-d-glucose (FDG). Materials and Methods: Nude mice bearing established human head and neck xenografts (HNX-OE; nu/nu mice) were locally irradiated (three fractions/week; 22 Gy) using a 150-kVp unit. Multiple FDG- and FLT-PET scans were acquired during treatment. Tumor volume was determined regularly, and tissue was analyzed for biomarkers involved in tracer uptake. Results: Both groups revealed a significant decline in tumor volume (P∈<∈0.01) compared to untreated tumors. For FDG as well as for FLT, a significant decline in retention was observed at day 4. For FLT, most significant decline in retention was observed at day 12; whereas, for FDG, this was already noted at day 4. Maximum decline in tumor-to-nontumor ratios (T/NT) for FDG and FLT was 42∈±∈18% and 49∈±∈16% (mean∈± ∈SD), respectively. FLT uptake was higher then that of FDG. For FLT, statistical significant correlations were found for both tumor volume at baseline and at day 29 with T/NT and ΔT/NT. All tumors demonstrated expression of glucose transporter-1, thymidine kinase-1, and hexokinase II. No differences were found for amount of tumor cells and necrosis at the end of treatment. Conclusion: This new experimental in vivo model supports the promise of using FLT-PET, as with FDG-PET, to monitor response to external radiotherapy. This warrants further clinical studies to compare these two tracers especially in cancers treated with radiotherapy

    The validity and precision of the leicester cough questionnaire in COPD patients with chronic cough

    Get PDF
    Background: A validated instrument to assess the effects of chronic cough on health status in patients with chronic obstructive pulmonary disease (COPD) is currently not available. The Leicester Cough Questionnaire (LCQ) is a cough-specific health status questionnaire which is originally validated for a population of general patients presenting with chronic cough. We examined the psychometric performance of the LCQ in patients with COPD and chronic productive cough. Methods: Concurrent validity, internal consistency, reproducibility and responsiveness were determined. The St. George's Respiratory Questionnaire (SGRQ) and the Short Form-36 (SF-36) were used as external criteria. Questionnaires were completed at the start of the study. After 2 and 12 weeks the LCQ was repeated, together with a global rating of change. Results: In total 54 patients were included. Concurrent validity analysis showed significant correlations between corresponding domains of the LCQ and the SGRQ (r(s) - 0.31 to - 0.60). Corresponding domains of the LCQ and the SF-36 showed weaker correlations (r(s) 0.04 to 0.41). Internal consistency was adequate for two of the three domains (Cronbach's alpha 0.74 - 0.86). Test-retest reliability in stable patients was high (intraclass correlation coefficients 0.79 - 0.93). The mean difference after two weeks was 0.73 (+/- 1.75). Responsiveness analysis indicated that the LCQ was able to detect changes after 12 weeks. Conclusion: The LCQ is a valid, reliable, responsive instrument to measure health status in COPD patients with chronic productive cough

    HPV testing on self collected cervicovaginal lavage specimens as screening method for women who do not attend cervical screening: cohort study

    Get PDF
    Objective To determine whether offering self sampling of cervicovaginal material for high risk human papillomavirus (HPV) testing is an effective screening method for women who do not attend regular cervical screening programmes

    Parotid salivary sodium levels of Sjögren's syndrome patients suggest B-cell mediated epithelial sodium channel disruption

    Get PDF
    Patients with primary Sjögren's syndrome (SS) suffer widely from lack of saliva production. Here we investigate potential mechanisms underpinning changes in SS patient saliva composition. Sodium concentration was significantly higher in all saliva samples collected: unstimulated submandibular/sublingual (SmSl) saliva (p<0.0001), stimulated SmSl saliva (p=0.002) and stimulated parotid (PG) (p<0.0001) saliva, compared to non-SS sicca controls. Chloride, phosphate and potassium ion concentrations, α-amylase activity and total protein content correlations were less consistently changed between SS and non-SS saliva types. Stimulated PG salivary sodium levels correlated with the degree of CD45+ lymphocytic cell infiltrate in the parotid glands (r=0.69, p<0.001), and even more strongly so with infiltrating CD20+ B cells (r=0.73, p<0.0001). CD3+ T cells were only moderately correlated with salivary sodium (r=0.23, p=0.015). In non-SS control or focus score (FS) negative SS PG tissue, the epithelial sodium channel (ENaC), responsible for sodium transport out of saliva, was localised to the apical membrane of luminal striated duct cells. In PG tissue from FS+ SS patients, apical ENaC expression appeared absent. We hypothesise that B cell-related proinflammatory cytokines in SS salivary glands may dysregulate sodium transport channels in SS
    • …
    corecore