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Magnesium and sulfate are each known to affect calcite growth and dissolution, but little is known about their combined effects on calcite growth rates. We grew calcite using the constant composition approach at ambient conditions, monitoring inhibition in solutions of Mg2+ and SO42- individually and together. The growth rate for pure calcite averaged 4.35 × 10-6 mol m-2 s-1 but decreased to 0.34, 0.16, and 0.08 × 10-6 mol m-2 s-1 in solutions with 40 mM of SO42-, 13.3 mM of Mg2+, and 12.7 mM of MgSO4. We characterized the crystal form with scanning electron microscopy and atomic force microscopy. The {1010} crystal surface developed as the foreign ion concentration increased in the order SO42- < Mg2+ < MgSO4. Powder X-ray diffraction and X-ray photoelectron spectroscopy showed Mg incorporation of as much as 9.2 mol %. Mg2+ inhibits calcite growth more effectively when SO42- is also present, which we interpret to be the result of MgSO4 ion pair formation. Sulfate promotes Mg2+ dehydration, thereby allowing calcite uptake at lower temperatures. These results improve general understanding about the controls on biomineralisation and imply a need for re-examining the validity of the Mg/Ca thermometer, which uses the Mg composition in foraminifer for interpreting ancient seawater temperatures. [ABSTRACT FROM AUTHOR]

Aim In the renal collecting ducts, ATP stimulates a Ca2+-activated chloride current. The identity of the channel responsible for the current under physiological conditions is not known and it was hypothesized that TMEM16a is a relevant candidate in the renal collecting duct. Methods The cortical collecting duct cell line M-1 was used as a model of the collecting duct. The ATP induced Ca2+ signalling was imaged in cells loaded with Ca2+-sensitive fluorescent probes using confocal laser-scanning fluorescence microscopy. Chloride current was determined by mounting M-1 cell layers in Ussing chamber. The expression of TMEM16a in human kidney was tested by immunohistochemistry. Results M-1 cells displayed a transient increase in intracellular Ca2+ concentration in response to 100 n m ATP. This response was completely blocked by addition of 100 μ m suramin, indicating that ATP signals through purinergic P2 receptors. Apical addition of 100 n m ATP induced a Cl- current, which was blocked by suramin, DPC and the cysteine-modifying compound MTSET. M-1 cells were found to express TMEM16a at the mRNA and protein level. Functionally, it was found that knock-down of TMEM16a expression in M-1 cells inhibited the ATP induced Cl--current. In human and mouse kidney sections, TMEM16a protein expression was localized to the collecting duct, and TMEM16a was found to be excreted in human urinary exosomes. Conclusion TMEM16a is a Ca2+-activated Cl- channel expressed in the collecting ducts. [ABSTRACT FROM AUTHOR]

Two hundred and thirty migraineurs diagnosed by their general practitioners in accordance with their usual practice were included. The patients treated two migraine attacks at home by subcutaneous injection of sumatriptan or placebo and the alternative medication for the second attack (cross-over). When sumatriptan was compared to placebo, significantly more of the 209 evaluable patients reported headache relief at one hour (56% v 8%, p < 0.001) and two hours (62% v 15%, p < 0.001) after the first injection. Resolution of nausea, photophobia and phonophobia was significantly more common in patients on sumatriptan than on placebo (p < 0.001 for all comparisons). The adverse events were usually transient and of mild or moderate severity, although, three patients withdrew due to adverse events. Ninety-five percent of patients evaluated by a neurological research fellow met the International Headache Society's criteria for migraine. In general practice, sumatriptan taken subcutaneously using an autoinjector at home was an effective and well tolerated acute treatment for migraine.

We have evaluated a new immunoturbidimetric assay (DCA 2000 HbA1c system, Bayer, Denmark) for determination of HbA1c. The aim of the study was to evaluate accuracy, precision and feasibility for the DCA 2000 method when employed in a diabetes centre by a technical assistant and at a general practitioner's by non lab staff. The results were compared with a high performance liquid chromatographic method (HPLC, AUTO A1C, Kyoto Daiichi Kagaku Co., Kyoto, Japan) which is the current laboratory method, and therefore used as reference. Assay time for the DCA 2000 method was nine minutes, while the HbA1c result was displayed within four minutes by HPLC. Blood samples were drawn after informed consent from 118 patients during a period of two months at the out-patient clinic of the Dept. of Paediatrics, Glostrup Hospital (n = 67) and at a general practitioner's (n = 51). Each sample was analyzed twice by each method on two consecutive days. In the HbA1c range from four to 14% (n = 67) the average within-assay precision (SD) for the HPLC method was 0.13%, whilst it was 0.23% for the DCA 2000 method (p < 0.001). The within-assay precision was low and acceptable, and for both methods it was independent of the current HbA1c concentration. For the DCA method precision was almost similar (p > 0.07) when carried out by a technical assistant (SD: 0.20%) and by non lab staff (SD: 0.25%). Interbatch variations for HbA1c results investigated with two different batches of reagents within a month were SD 0.30% (HbA1c range: 4.9-5.9%, n = 30) and SD 0.44% (HbA1c range: 10.5-12.1%, n = 30) for these two preparations.(ABSTRACT TRUNCATED AT 250 WORDS)

One hundred and twenty (120) women, taking contraceptive pills, underwent a structured interview with a view elucidating their knowledge of the physiology of menstruation, the action and side effects of contraceptive pills and their compliance in the taking of contraceptive pills. The most important sources of information were the medical letters in magazines and the women's own doctors, while the teaching in the Folkeskole (primary and lower secondary school) had not had any major influence on the level of information. Well over one third of the interviewed women knew the most important action mechanism of the contraceptive pill, and half of the women could give a satisfactory explanation of the physiology of menstruation. Twenty-four percent (24%) thought that pregnancy could not occur until 1-2 months after the woman had ceased taking the pill. There was high compliance among the women i.e. that their behavior was correct when they had forgotten to take one or two contraceptive pills, when bleeding was irregular, and when beginning on a new package of pills. Eighty-three percent (83%) had experienced side effects that could be related to contraceptive pills. The investigation shows that there is a need for more efficient information about the effects of the Pill and about the physiology of menstruation.

The purpose of this study was to clarify whether there was any agreement between knowledge about coronary risk factors, attitudes to individual prevention of coronary heart disease and preventive health behaviour. In particular the differences between males and females were examined. A total of 749 persons ranging in age between 25 and 44 (that is 82% of a random group of 917 persons) were interviewed in this cross sectional study. Physical inactivity, smoking and fat consumption were used as behaviour related risk factors. Generally, young adult Danes had a poor knowledge and poor health behaviour related to coronary heart disease in spite of their positive attitudes towards prevention. The study indicated that neither attitudes nor knowledge were correlated to preventive health behaviour. Women had better health behaviour patterns than men despite the same amount of knowledge and attitudes. In the above mentioned connexions, men showed positive correlation while no correlation existed for women.