383 research outputs found

    Proton binding by groundwater fulvic acids of different age, origins, and structure modeled with the model V and NICA-Donnan model

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    The proton binding properties of four fulvic acids from pristine groundwater and leachate-polluted groundwater were measured at four different ionic strengths (0.005−0.12 M) and modeled by the Model V and the NICA−Donnan model in order to evaluate the necessity of detailed proton binding parameters for groundwater fulvic acids. The proton binding parameters derived from the various fulvic acids were very similar, and on the basis of these parameters, it was not possible to distinguish between pristine and polluted groundwater. Normalization of the proton charge density by the proton charge density at pH 7 for each fulvic acid made all four fulvic acids regress to the same curve. The effects of varying the proton binding parameters were evaluated by simulating cadmium complexation using sets of proton binding parameters for the four fulvic acids and default sets of proton binding parameters available in the models WHAM (based on Model V) and Ecosat (based on NICA−Donnan). The Model V was rather indifferent with respect to specific characteristics of fulvic acids proton binding, and for most practical uses, the default values available in the model can be used. The NICA−Donnan model resulted in larger deviations between simulations based on default values and specific parameters. However, the NICA−Donnan database is still rather limited, and specific proton binding parameters should be used until the database providing default values has been extended

    Vitamin D vitamers affect vitamin D status differently in young healthy males

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    Dietary intake of vitamin D includes vitamin D3 (vitD3), 25-hydroxyvitamin D3 (25OH-D3), and vitamin D2 (vitD2). However, the bioactivity of the different species has not been scientifically established. The hypothesis in this study was that vitD3, 25OH-D3, and vitD2 have an equal effect on 25-hydroxyvitamin D in serum (vitamin D status). To test our hypothesis, we performed a randomized, crossover study. Twelve young males consumed 10 µg/day vitD3 during a four-week run-in period, followed by 3 × 6 weeks of 10 µg/day vitD3, 10 µg/day 25OH-D3, and 10 µg/day vitD2. The content of vitD3, vitD2, 25OH-D3, and 25-hydroxyvitamin D2 (25OH-D2) in serum was quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The hypothesis that the three sources of vitamin D affect vitamin D status equally was rejected. Based on the assumption that 1 µg vitD3/day will show an increase in vitamin D status of 1.96 nmol/L, the results showed that 23 µg vitD2 and 6.8 µg 25OH-D3 was similar to 10 µg vitD3. These results demonstrate that further investigations are necessary to determine how to quantify the total vitamin D activity based on chemical quantification of the individual vitamin D metabolites to replace the total vitamin D activity assessed in biological rat models

    A walk-in clinic as an alternative approach to reaching non-attenders of the cervical cancer screening program in the North Denmark region-a pilot study

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    INTRODUCTION: Up to 39% of women in Denmark do not participate regularly in the cervical cancer screening program and initiatives to increase participation are called upon. The primary aim of this study was to describe previous screening history and characteristics of women attending screening in a walk‐in clinic. Furthermore, we wanted to investigate barriers to cervical cancer screening. MATERIAL AND METHODS: We designed a walk‐in clinic that was open 2 days a week from 16.00 to 19.00 h, located in the Departments of Gynecology in the two main hospitals of the North Denmark Region. The main purpose of the clinic was cervical cancer screening and the study period was 5 months. Women who were not eligible for screening or had other health complaints were referred to their general practitioner. The women included in the study, filled out a questionnaire regarding educational and occupational status; their screening history was registered using data from the Danish Pathology Register. RESULTS: During the study period, 255 women visited the walk‐in clinic. The final study population consisted of 249 women who met the inclusion criteria. Age range of participants was 23–77 years, with a median age of 45 years. The majority of the participants were currently employed (81%) or students (10%), the remaining being retired (5%) or unemployed (4%). Screening history showed that 138 (55.4%) of the women were on time for the screening or delayed less than 6 months compared to their recommended screening interval. Sixty‐one women (24.5%) were delayed >6 months but <2 years. Fifty women (20.1%) were classified as non‐attenders, with more than a 2‐year delay in their screening. In the group of non‐attenders, eight women had never been screened. Of the remaining 42 women, the median time since last screening was 8.2 years (range 5.0–25.3 years). CONCLUSIONS: Women attending the walk‐in clinic tended to be primarily actively working or students (91%). All age groups in the screening population were represented. Screening history showed that 44.6% had not followed the recommended screening program

    »Så de lod mig bare være …« – eksempler på veje fra psykiatrisk til retspsykiatrisk patient

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    AbstractThe aim of this study is to provide various perspectives on two examples in which long term psychiatric patients committed serious crimes and consequently became mentally disordered offenders. The two patients involved were found guilty, but were not punishable under Danish law and were instead sentenced to placement in a psychiatric facility. When looking at these cases from the perspective of various stakeholders, e.g., relatives, health care professionals, the patients themselves, a number of potential risk and protective factors come to light. The analysis is followed by a discussion of whether similar situations can be prevented and, if so, how. We recommend an intensified focus on risk and protective factors, as well as preventive measures, and an increased cooperation and knowledge sharing between patients, relatives, networks, hospital psychiatry and psychosocial rehabilitation units provided within municipalities

    QT Measurement and Heart Rate Correction during Hypoglycemia: Is There a Bias?

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    Introduction. Several studies show that hypoglycemia causes QT interval prolongation. The aim of this study was to investigate the effect of QT measurement methodology, heart rate correction, and insulin types during hypoglycemia. Methods. Ten adult subjects with type 1 diabetes had hypoglycemia induced by intravenous injection of two insulin types in a cross-over design. QT measurements were done using the slope-intersect (SI) and manual annotation (MA) methods. Heart rate correction was done using Bazett's (QTcB) and Fridericia's (QTcF) formulas. Results. The SI method showed significant prolongation at hypoglycemia for QTcB (42(6) ms; P < .001) and QTcF (35(6) ms; P < .001). The MA method showed prolongation at hypoglycemia for QTcB (7(2) ms, P < .05) but not QTcF. No difference in ECG variables between the types of insulin was observed. Discussion. The method for measuring the QT interval has a significant impact on the prolongation of QT during hypoglycemia. Heart rate correction may also influence the QT during hypoglycemia while the type of insulin is insignificant. Prolongation of QTc in this study did not reach pathologic values suggesting that QTc prolongation cannot fully explain the dead-in-bed syndrome

    Phenothiazines as a solution for multidrug resistant tuberculosis: From the origin to present

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    Historically, multiplicity of actions in synthetic compounds is a rule rather than exception. The science of non-antibiotics evolved in this background. From the antimalarial and antitrypanosomial dye methylene blue, chemically similar compounds, the phenothiazines, were developed. The phenothiazines were first recognised for their antipsychotic properties, but soon after their antimicrobial functions came to be known and then such compounds were designated as non-antibiotics. The emergence of highly drug-resistant bacteria had initiated an urgent need to search for novel affordable compounds. Several phenothiazines awakened the interest among scientists to determine their antimycobacterial activity. Chlorpromazine, trifluoperazine, methdilazine and thioridazine were found to have distinct antitubercular action. Thioridazine took the lead as researchers repeatedly claimed its potentiality. Although thioridazine is known for its central nervous system and cardiotoxic side-effects, extensive and repeated in vitro and in vivo studies by several research groups revealed that a very small dose of thioridazine is required to kill tubercle bacilli inside macrophages in the lungs, where the bacteria try to remain and multiply silently. Such a small dose is devoid of its adverse side-effects. Recent studies have shown that the (&ndash;) thioridazine is a more active antimicrobial agent and devoid of the toxic side effects normally encountered. This review describes the possibilities of bringing down thioridazine and its (&ndash;) form to be combined with other antitubercular drugs to treat infections by drug-resistant strains of Mycobacterium tuberculosis and try to eradicate this deadly disease. [Int Microbiol 2015; 18(1):1-12]Keywords: Mycobacterium tuberculosis &middot; phenotiazines &middot; thioridazine &middot; tuberculosi
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