194 research outputs found

    Geochemical speciation of mercury in bauxite

    Get PDF
    The presence of trace concentrations of mercury in bauxite is a potential environmental concern in the Bayer alumina refining process. An understanding of the geochemical speciation of mercury in bauxite provides insight into the behaviour of mercury in the Bayer process. The speciation of mercury was evaluated using a novel continuous thermal desorption methodology, sequential extractions, alkaline digestion, aqua regia digestion and hydrofluoric acid total dissolution assay. Thermal desorption demonstrated two distinct mercury forms. Labile mercury was found to be present as metacinnabar or organic-associated mercury, while refractory mercury was associated with quartz or other refractory silicates

    Home parenteral nutrition with an omega-3-fatty-acid-enriched MCT/LCT lipid emulsion in patients with chronic intestinal failure (the HOME study):study protocol for a randomized, controlled, multicenter, international clinical trial

    Get PDF
    BACKGROUND: Home parenteral nutrition (HPN) is a life-preserving therapy for patients with chronic intestinal failure (CIF) indicated for patients who cannot achieve their nutritional requirements by enteral intake. Intravenously administered lipid emulsions (ILEs) are an essential component of HPN, providing energy and essential fatty acids, but can become a risk factor for intestinal-failure-associated liver disease (IFALD). In HPN patients, major effort is taken in the prevention of IFALD. Novel ILEs containing a proportion of omega-3 polyunsaturated fatty acids (n-3 PUFA) could be of benefit, but the data on the use of n-3 PUFA in HPN patients are still limited. METHODS/DESIGN: The HOME study is a prospective, randomized, controlled, double-blind, multicenter, international clinical trial conducted in European hospitals that treat HPN patients. A total of 160 patients (80 per group) will be randomly assigned to receive the n-3 PUFA-enriched medium/long-chain triglyceride (MCT/LCT) ILE (Lipidem/Lipoplus¼ 200 mg/ml, B. Braun Melsungen AG) or the MCT/LCT ILE (Lipofundin¼ MCT/LCT/Medialipide¼ 20%, B. Braun Melsungen AG) for a projected period of 8 weeks. The primary endpoint is the combined change of liver function parameters (total bilirubin, aspartate transaminase and alanine transaminase) from baseline to final visit. Secondary objectives are the further evaluation of the safety and tolerability as well as the efficacy of the ILEs. DISCUSSION: Currently, there are only very few randomized controlled trials (RCTs) investigating the use of ILEs in HPN, and there are very few data at all on the use of n-3 PUFAs. The working hypothesis is that n-3 PUFA-enriched ILE is safe and well-tolerated especially with regard to liver function in patients requiring HPN. The expected outcome is to provide reliable data to support this thesis thanks to a considerable number of CIF patients, consequently to broaden the present evidence on the use of ILEs in HPN. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT03282955. Registered on 14 September 2017

    High-pressure phases of uranium monophosphide studied by synchrotron x-ray diffraction

    Get PDF
    X-ray diffraction studies have been performed on UP powder for pressures up to 51 GPa using synchrotron radiation and a diamond-anvil cell. At ambient pressure UP has the rocksalt structure. The bulk modulus has been determined to B0_0=102(4) GPa and its pressure derivative to B'0_0 =4.0(8). The cubic phase has been found to transform to a new phase, UP II, at about 10 GPa. UP II can be characterized by a rhombohedral Bravais lattice. UP II transforms to an orthorhombic phase, UP III, at 28 GPa. No volume change has been observed at the two transitions. The influence of the 5f electrons on the transformations is discussed

    An international study of the quality of life of adult patients treated with home parenteral nutrition

    Get PDF
    Background & aims: Home parenteral nutrition-quality of life (HPN-QOL©) is a self-assessment tool for the measurement of QOL in patients on HPN. The aims of this study were: to re-assess the basic psychometric properties of the HPN-QOL© in a multinational sample of adult patients; to provide a description of QOL dimensions by short and long HPN treatment duration; to explore clinical factors potentially associated to QOL scores. Methods: Patients (n = 699) from 14 countries completed the HPN-QOL©. The questionnaires were analysed to evaluate data completeness, convergent/discriminant validity and internal-consistency reliability. The association of overall QOL and HPN treatment duration as well as other clinical factors were investigated using multivariable linear regression models. Results: The analysis of the multitrait-scaling and internal consistency indicates a good fit with the questionnaire structure for most items. Item discriminant validity correlation was satisfactory and psychometric evaluation of the HPN-QOL© in the different English, French and Italian language patient sub-groups confirmed psychometric equivalence of the three questionnaire versions. The results of the multivariable linear regression showed that QOL scores were significantly associated with HPN duration (better in long-term), underlying disease (better in Crohn's disease and mesenteric ischaemia) and living status (worse in living alone) and, after adjusting for the other factors, with the number of days of HPN infusion per week. Conclusions: The HPN-QOL©, is a valid tool for measurement of QOL in patients on HPN, to be used in the clinical practice as well as in research

    Bone pain and extremely low bone mineral density due to severe vitamin D deficiency in celiac disease

    Get PDF
    Case report A 29-year-old wheelchair-bound woman was presented to us by the gastroenterologist with suspected osteomalacia. She had lived in the Netherlands all her life and was born of Moroccan parents. Her medical history revealed iron deficiency, growth retardation, and celiac disease, for which she was put on a gluten-free diet. She had progressive bone pain since 2 years, difficulty with walking, and about 15 kg weight loss. She had a short stature, scoliosis, and pronounced kyphosis of the spine and poor condition of her teeth. Laboratory results showed hypocalcemia, an immeasurable serum25-hydroxyvitamin D level, and elevated parathyroid hormone and alkaline phosphatase levels. Spinal radiographs showed unsharp, low contrast vertebrae. Bone mineral density measurement at the lumbar spine and hip showed a T-score of -6.0 and -6.5, respectively. A bone scintigraphy showed multiple hotspots in ribs, sternum, mandible, and long bones. A duodenal biopsy revealed villous atrophy (Marsh 3C) and positive antibodies against endomysium, transglutaminase, and gliadin, compatible with active celiac disease. A bone biopsy showed severe osteomalacia but normal bone volume. She was treated with calcium intravenously and later orally. Furthermore, she was treated with high oral doses of vitamin D and a gluten-free diet. After a few weeks of treatment, her bone pain decreased, and her muscle strength improved. Discussion In this article, the pathophysiology and occurrence of osteomalacia as a complication of celiac disease are discussed. Low bone mineral density can point to osteomalacia as well as osteoporosis. © International Osteoporosis Foundation and National Osteoporosis Foundation 2011
    • 

    corecore