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21.
OBJECTIVE: This article describes results from a study investigating the effects of using long assessment instruments on attrition rates in mailed-out surveys. METHOD: Participants were randomly assigned to receive one of two versions of a mailed-out survey; one version incorporated a detailed assessment of drinking using the Timeline Follow back method (TLFB; n = 46) and the other employed a brief graduated frequency measure of alcohol consumption (n = 49). RESULTS: 29% fewer respondents who received the TLFB returned any of their survey materials as compared to those respondents who received just the graduated frequency measure (22% vs 51%). CONCLUSIONS: In some situations, e.g., mailed-out surveys, employing detailed survey instruments may not be justified as the increased respondent burden may result in increased attrition rates.  相似文献   
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A major aflatoxin G1 (AFG1)-albumin adduct has been identifiedand characterized in rats following exposure to AFG1. The productisolated from a Pronase digest of in vivomodified albumin wasidentical by chromatographic retention time to the syntheticproduct obtained by the acylase-catalysed deacetylation productof N-acetyl-L-lysine with 8,9-dihydro- 8,9-dibromo-AFG1. Thein vitro product, AFG1-lysine, was characterized by UV, fluorescence,1H- and 13C-NMR spectroscopy and fast atom bombardment MS. Acompetitive enzyme-linked immunoassay for this adduct was establishedusing polyclonal antibodies to AFB, and this was used togetherwith an HPLC-fluorescence technique to quantitate the in vivoformation of AFG1–albumin adducts in comparison to AFB1.A linear dose–response relationship was observed in ratsfollowing single exposures to 0.1– 3 mg AFG1/kg body wt.The levels of AFG1-albumin adducts were determined to be 5.7-and 2.8-fold lower than with equivalent doses of AFB1 as determinedby immunoassay and HPLC fluorescence respectively. The lowerbinding of AFG1 and the lower levels in the human food supplycompared to AFB, suggest that the newly identified adduct couldbe added as an internal standard for methods using the measurementof aflatoxin-albumin adducts to quantitate human exposure toaflatoxin.  相似文献   
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High rates of hepatocellular carcinoma (HCC) in The Gambia, West Africa, are primarily due to a high prevalence of chronic hepatitis B virus infection and heavy aflatoxin exposure via groundnut consumption. We investigated genetic polymorphisms in carcinogen-metabolizing (GSTM1, GSTT1, HYL1*2) and DNA repair (XRCC1) enzymes in a hospital-based case-control study. Incident HCC cases (n = 216) were compared with frequency-matched controls (n = 408) with no clinically apparent liver disease. Although the prevalence of variant genotypes was generally low, in multivariable analysis (adjusting for demographic factors, hepatitis B virus, hepatitis C virus, and TP53 status), the GSTM1-null genotype [odds ratio (OR), 2.45; 95% confidence interval (95% CI), 1.21-4.95] and the heterozygote XRCC1-399 AG genotype (OR, 3.18; 95% CI, 1.35-7.51) were significantly associated with HCC. A weak association of the HYL1*2 polymorphism with HCC was observed but did not reach statistical significance. GSTT1 was not associated with HCC. The risk for HCC with null GSTM1 was most prominent among those with the highest groundnut consumption (OR, 4.67; 95% CI, 1.45-15.1) and was not evident among those with less than the mean groundnut intake (OR, 0.64; 95% CI, 0.20-2.02). Among participants who had all three suspected aflatoxin-related high-risk genotypes [GSTM1 null, HLY1*2 (HY/HH), and XRCC1 (AG/GG)], a significant 15-fold increased risk of HCC was observed albeit with imprecise estimates (OR, 14.7; 95% CI, 1.27-169). Our findings suggest that genetic modulation of carcinogen metabolism and DNA repair can alter susceptibility to HCC and that these effects may be modified by environmental factors.  相似文献   
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ObjectivesDesign and build a portable xenon-129 (129Xe) hyperpolariser for clinically accessible 129Xe lung MRI.MethodsThe polariser system consists of six main functional components: (i) a laser diode array and optics; (ii) a B0 coil assembly; (iii) an oven containing an optical cell; (iv) NMR and optical spectrometers; (v) a gas-handling manifold; and (vi) a cryostat within a permanent magnet. All components run without external utilities such as compressed air or three-phase electricity, and require just three mains sockets for operation. The system can be manually transported in a lightweight van and rapidly installed on a small estates footprint in a hospital setting.ResultsThe polariser routinely provides polarised 129Xe for routine clinical lung MRI. To test the concept of portability and rapid deployment, it was transported 200 km, installed at a hospital with no previous experience with the technology and 129Xe MR images of a diagnostic quality were acquired the day after system transport and installation.ConclusionThis portable 129Xe hyperpolariser system could form the basis of a cost-effective platform for wider clinical dissemination and multicentre evaluation of 129Xe lung MR imaging.Advances in knowledgeOur work successfully demonstrates the feasibility of multicentre clinical 129Xe MRI with a portable hyperpolariser system.  相似文献   
26.
BACKGROUND: The purpose of this study was to determine whether there was a relationship between disease activity and health functioning, as measured by a range of patient-reported outcome (PRO) measures in patients with follicular lymphoma (FL). PATIENTS AND METHODS: A total of 222 patients with FL were recruited from eight sites across the UK and they completed a number of PRO measures. The participants were analyzed across five disease states: 'active disease-newly diagnosed', 'active disease-relapsed', 'partial response', 'complete response' and 'disease free'. The relationship between these disease states and their level of health functioning was assessed as well as the relationship between being 'on' or 'off' chemotherapy and disease state. RESULTS: In terms of health-related quality of life (HRQoL), participants in the relapsed category had the lowest mean physical well-being, emotional well-being, functional well-being and social well-being score. In a regression analysis, the 'active disease-relapsed' group acted as a significant predictor for each PRO variable. In addition, the remission group acted as a significant predictor of high anxiety scores as measured by the Hospital Anxiety and Depression Scale. CONCLUSION: The results of this study demonstrate that various aspects of patient-reported health outcomes differ according to disease state in patients with FL. For those patients who have relapsed, they are more likely to experience worse HRQoL and other patient-reported health outcomes than patients newly diagnosed, in partial or complete remission or when completely disease free.  相似文献   
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There is no consensus concerning the treatment of radial nerve palsy after humeral shaft fractures. The prevalence varies between 2 and 17%. Therefore, it is considered to be the most common nervous lesion in trauma. There are different strategies of treatment. On the one hand, there is the possibility of early exploration to exclude an interposition or a loss of continuity. On the other hand, a wait-and-see procedure is often warranted due to the high rate of spontaneous recoveries (75% and more). If there is damage to the radial nerve regarding loss of continuity or an interposition in the fracture, then clinical results obtained after delayed surgical revision are poorer than in the case of early revision. Thus, close clinical follow-up of the patient is important. However, based on the high rate of spontaneous remissions, early nerve exploration should take place only in exceptional cases.  相似文献   
29.
Leukocyte adhesion deficiency II (LAD II) is a rare congenital disease caused by defective fucosylation leading to immuno-deficiency and psychomotor retardation. We have previously identified the genetic defect of LAD II in a patient whose Golgi GDP-fucose transporter (GFTP) bears a single amino acid exchange that renders this protein nonfunctional but correctly localized to the Golgi. We now report a novel dual defect by which a truncated GFTP causes the disease in a new LAD II patient. We show that the truncation renders this GFTP unable to localize to the Golgi, the compartment where it is required. Furthermore, the missing part of the GFTP can be dissected into 2 regions, one that is needed for Golgi localization and one that is additionally required for the function of the GFTP. We investigated the subcellular localization of all known defective GFTPs allowing us to divide all genetically analyzed LAD II patients into 2 groups, one in which single amino acid exchanges in the GFTP impair its function but not its subcellular localization, and another group with a dual defect in function and Golgi expression of the GFTP due to the absence of 2 important molecular regions.  相似文献   
30.
Background: Aflatoxin and fumonisin are toxic food contaminants. Knowledge about effects of their exposure and coexposure on child growth is inadequate.Objective: We investigated the association between child growth and aflatoxin and fumonisin exposure in Tanzania.Methods: A total of 166 children were recruited at 6–14 months of age and studied at recruitment, and at the 6th and 12th month following recruitment. Blood and urine samples were collected and analyzed for plasma aflatoxin–albumin adducts (AF-alb) using ELISA, and urinary fumonisin B1 (UFB1) using liquid chromatography–mass spectrometry, respectively. Anthropometric measurements were taken, and growth index z-scores were computed.Results: AF-alb geometric mean concentrations (95% CIs) were 4.7 (3.9, 5.6), 12.9 (9.9, 16.7), and 23.5 (19.9, 27.7) pg/mg albumin at recruitment, 6 months, and 12 months from recruitment, respectively. At these respective sampling times, geometric mean UFB1 concentrations (95% CI) were 313.9 (257.4, 382.9), 167.3 (135.4, 206.7), and 569.5 (464.5, 698.2) pg/mL urine, and the prevalence of stunted children was 44%, 55%, and 56%, respectively. UFB1 concentrations at recruitment were negatively associated with length-for-age z-scores (LAZ) at 6 months (p = 0.016) and at 12 months from recruitment (p = 0.014). The mean UFB1 of the three sampling times (at recruitment and at 6 and 12 months from recruitment) in each child was negatively associated with LAZ (p < 0.001) and length velocity (p = 0.004) at 12 months from recruitment. The negative association between AF-alb and child growth did not reach statistical significance.Conclusions: Exposure to fumonisin alone or coexposure with aflatoxins may contribute to child growth impairment.Citation: Shirima CP, Kimanya ME, Routledge MN, Srey C, Kinabo JL, Humpf HU, Wild CP, Tu YK, Gong YY. 2015. A prospective study of growth and biomarkers of exposure to aflatoxin and fumonisin during early childhood in Tanzania. Environ Health Perspect 123:173–178; http://dx.doi.org/10.1289/ehp.1408097  相似文献   
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