1. |
|
|
2. |
|
|
3. |
|
|
4. |
|
|
5. |
|
|
6. |
- Clarke, Robert, et al.
(författare)
-
Lowering blood homocysteine with folic acid based supplements : Meta-analysis of randomised trials
- 1998
-
Ingår i: British Medical Journal. - : BMJ. - 0959-8146. ; 316:7135, s. 894-898
-
Forskningsöversikt (refereegranskat)abstract
- Objective: To determine the size of reduction in homocysteine concentrations produced by dietary supplementation with folic acid and with vitamins B-12 or B-6. Design: Meta-analysis of randomised controlled trials that assessed the effects of folic acid based supplements on blood homocysteine concentration. Multivariate regression analysis was used to determine the effects on homocysteine concentrations of different doses of folic acid and of the addition of vitamin B-12 or B-6. Subjects: Individual data on 1114 people included in 12 trials. Findings: The proportional and absolute reductions in blood homocysteine produced by folic acid supplements were greater at higher pretreatment blood homocysteine concentrations (P < 0.001) and at lower pretreatment blood folate concentrations (P < 0.001). After standardisation to pretreatment blood concentrations of homocysteine of 12 μmol/l and of folate of 12 nmol/l (approximate average concentrations for Western populations), dietary folic acid reduced blood homocysteine concentrations by 25% (95% confidence interval 23% to 28%; P < 0.001), with similar effects in the range of 0.5-5 mg folic acid daily. Vitamin B-12 (mean 0.5 mg daily) produced an additional 7% (3% to 10%) reduction in blood homocysteine. Vitamin B-6 (mean 16.5 mg daily) did not have a significant additional effect. Conclusions: Typically in Western populations, daily supplementation with both 0.5-5 mg folic acid and about 0.5 mg vitamin B-12 would be expected to reduce blood homocysteine concentrations by about a quarter to a third (for example, from about 12 μmol/l to 8-9 μmol/l). Large scale randomised trials of such regimens in high risk populations are now needed to determine whether lowering blood homocysteine concentrations reduces the risk of vascular disease.
|
|
7. |
- Elimam, A, et al.
(författare)
-
Growth hormone treatment downregulates serum leptin levels in children independent of changes in body mass index
- 1999
-
Ingår i: Hormone research. - : S. Karger AG. - 0301-0163. ; 52:2, s. 66-72
-
Tidskriftsartikel (refereegranskat)abstract
- The changes in serum leptin levels during growth hormone (GH) treatment were studied in 27 children, 17 with GH deficiency (GHD), 10 with idiopathic short stature (ISS), and 9 with Prader-Willi syndrome (PWS). Within 1 month of GH treatment, serum leptin levels decreased by 40% in the GHD children (p < 0.01). There was no significant change in serum leptin level in the children with ISS. In children with PWS, the mean serum leptin level decreased by almost 60% after 3 months of treatment (p < 0.001). Thereafter, no further decline was observed in any of the 3 groups. Changes in body composition became evident first after the 3 months of treatment. In the GHD children, the BMI was unchanged while the mean body fat percentage was 2.7% lower after 1 year of GH treatment (p < 0.05). In the ISS children, neither BMI nor body fat percentage were significantly changed during treatment. The PWS children exhibited a significant decrease in BMI after 6 months of GH treatment without any further change during the remaining period of treatment. In this group, the mean body fat percentage decreased from 42 ± 2.4 to 28 ± 2.2% after treatment (p < 0.001). The finding that the fall in leptin occurs before changes in body composition become detectable suggests a direct effect of GH on leptin production, metabolism, or clearance.
|
|
8. |
|
|
9. |
|
|
10. |
- Lindgren, M., et al.
(författare)
-
Restitution of neurophysiological functions, performance, and subjective symptoms after moderate insulin-induced hypoglycaemia in non-diabetic men
- 1996
-
Ingår i: Diabetic Medicine. - : Wiley-Blackwell. - 0742-3071 .- 1464-5491. ; 13:3, s. 218-25
-
Tidskriftsartikel (refereegranskat)abstract
- The restoration of cognitive function was studied in 10 healthy men aged 26 years (25.5 +/- 1.2 years; mean +/- SD) after insulin-induced hypoglycaemia (arterialized blood glucose 2.5 +/- 0.4 mmol l-1) for 62 +/- 8 min. Another group of six men participated in a single blind sham study for comparison. The hypoglycaemic event caused a significant increase (p = 0.006) in serum adrenaline levels. Ratings of adrenergically mediated symptoms increased during hypoglycaemia (p = 0.006), as did neuroglycopenic symptoms (p = 0.002), although neuroglycopenia ratings increased in both studies. During hypoglycaemia, P300 amplitudes in a relatively demanding visual search task decreased (p = 0.02), whereas easier tasks were unaffected. The amplitudes were restored after 40 min of normoglycaemia. Reaction time deteriorated after restoration of normoglycaemia, suggesting an effect of hypoglycaemia on learning. Thus, hypoglycaemia at a blood glucose level that is common among patients treated with insulin causes clear cognitive dysfunction, although restoration of the cognitive dysfunction to normal was fast.
|
|