Biomedical subjects

T Koskinen

Publications and source records attributed to T Koskinen.

At least 37 records · Page 2Linked to original sources

PubMed1988

25-Hydroxyvitamin D and vitamin D in human milk: effects of supplementation and season.

Breast-milk 25-hydroxyvitamin D (25-[OH]D) and vitamin D were measured in mothers supplemented with 2000 or 1000 IU (50 or 25 micrograms) of vitamin D/d or with no supplementation. Fore- and hindmilk samples were collected at two stages of lactation (8 and 15 or 20 wk after delivery) and at different seasons. Season affected the levels of 25-(OH)D and vitamin D. The 25-(OH)D levels were higher in hind- than in foremilk. Supplementation had no effect on vitamin D levels. Milk 25-(OH)D levels of mothers receiving either 1000 or 2000 IU (25 or 50 micrograms) vitamin D/d were significantly higher than those of unsupplemented mothers in February and April. In theory, supplementation with 2000 IU (50 micrograms) vitamin D should have increased the calculated antirachitic activity of the milk in winter to the levels of unsupplemented mothers in September; however, responses varied widely among individuals.

Breast Feeding↗

PubMed1988

Double blind study on the need for vitamin D supplementation in prepubertal children.

Fifty-one healthy prepubertal schoolchildren were followed for 13 months in a double blind study. Twenty-four of them were supplemented with 400 IU of vitamin D2 5-7 times weekly, while 27 received a placebo. The children were examined in winter both at the beginning and at the end of the study, and in the middle of the study in autumn. Mean 25-hydroxyvitamin D levels in the supplemented group were significantly higher than those in the placebo group both in autumn and in winter, when the study ended. The vitamin D supplementation did not, however, affect other vitamin D metabolites, serum calcium, albumin, inorganic phosphorus, parathyroid hormone concentrations or alkaline phosphatase activity. Moreover, the supplementation caused no alterations in the weight or height gain or bone mineral content of the distal radius of the children, and thus subclinical rickets could not be shown.

Bone and Bones↗

PubMed1988

Serum vitamin A levels in mothers and their breast-fed term infants with or without supplemental vitamin A.

Serum concentrations of vitamin A were measured in term infants (n = 72) and their mothers at delivery and after 20 weeks of breast-feeding (n = 48). During the 20 weeks the infants received either no supplemental vitamin A (but the mothers were given 3,000 IU vitamin A daily) (n = 16) or a daily vitamin A supplementation of 600 (n = 17) or 1,500 IU (n = 15). After 20 weeks of breast-feeding the vitamin A levels in the unsupplemented infants were similar to those at birth. The infants supplemented either with 600 or 1,500 IU had higher vitamin A serum levels than at birth (p less than 0.01), however, there was no difference between the two supplemented groups. During lactation, the serum vitamin A concentrations of the mothers increased significantly in all groups with or without vitamin A supplementation.

Breast Feeding↗

PubMed1988

Serum levels of vitamin A, E, and selenium in women with lichen sclerosus of the vulva treated with etretinate.

Forty-six patients with Lichen sclerosus (Ls) of the vulva were treated with peroral etretinate for 3 months. The pretreatment serum levels of vitamins A and E, and selenium were measured. Etretinate therapy proved to be effective in the treatment of Ls; however, it did not affect the vitamin A status of the Ls patients. Vitamin E and selenium levels did not differ from the control values, nor did they have any prognostic value.

Etretinate↗

PubMed1988

Serum profiles of vitamins A, E and D in mares and foals during different seasons.

Twenty mares and 15 foals of the Finnhorse breed were used to determine serum levels of vitamins A, E and D during different seasons. Monthly serum samples were analyzed from mares for 22 mo and from foals for 13 mo after birth. The horses were kept on pasture from early June until early October and in stables during the winter months. Seasonal differences (P less than .001) were found in serum retinol, retinol to protein ratio, alpha-tocopherol and alpha-tocopherol to cholesterol ratio. Values were lowest from February through May and highest from June through August. Serum levels of retinol and alpha-tocopherol of the foals were much lower (P less than .001) than in mares during the first 4 mo of life. As in the mares, serum levels of retinol and alpha-tocopherol decreased (P less than .001) in winter. At 1 yr of age, serum levels of these vitamins increased rapidly on pasture to values that were close to those found in adult horses. Serum 25-hydroxyvitamin D levels were very low throughout the year. However, a small seasonal variation also was found in 25-hydroxyvitamin D concentrations in the mares. Serum 1,25-dihydroxyvitamin D levels in pregnant mares in winter were similar to those found in lactating mares in summer. These levels also were low compared with those in animals of other species.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1988

Serum 25-OHD, vitamin A and vitamin E concentrations in healthy Finnish and Floridian women.

The concentrations of 25-hydroxyvitamin D (25-OHD), vitamin A and vitamin E were measured in serum samples of Finnish and Floridian women; the samples were collected in spring. The Floridians had twice as much 25-OHD in serum as the Finns, but the levels of the two other fat-soluble vitamins were equal. Thus, in Florida there is very little risk for vitamin D deficiency, and vitamin A and E status seems to be unaffected by differences in dietary habits.

Calcifediol↗

PubMed1987

Serum vitamins A and E and carotene in patients with gynecologic cancer.

Serum concentrations of vitamin A (retinol), vitamin E (alpha-tocopherol) and total carotene were measured in 88 women with gynecologic cancer (9 vulvar, 15 cervical, 36 endometrial and 28 ovarian carcinomas) and 31 healthy controls. No significant differences were found in the serum levels of the vitamins and carotene in patients with vulvar, cervical or endometrial cancer compared to the controls. The patients with ovarian cancer had a significantly (P less than 0.01) lower mean serum level of vitamin A than the controls, while carotene and vitamin E level were similar in both groups. The results indicate that vitamin A may have a role in the metabolism of patients with advanced ovarian cancer.

Aged↗

PubMed1987

Bone density, histomorphometry and biochemistry in patients with fractures of the hip or spine.

Bone density in the lumbar spine and distal radius, histomorphometric values of iliac crest biopsies and biochemical parameters, including vitamin D metabolites, were determined in 30 women with recent hip fractures and in 19 women with spinal fragility fractures. In both groups, as compared with age- and sex-matched controls, bone density in the spine and peripheral skeleton was reduced. In the peripheral skeleton the degree of osteopenia in the two groups was equal, but loss of trabecular bone in the spine was disproportionate and more extensive in the group with spinal fragility fractures. In the patients with hip fractures the percentage of trabecular bone occupied by osteoid in the iliac crest biopsies was increased in 11 of the 25 patients. Osteomalacia was further suggested by the lower mean levels of serum calcium and phosphate and lower mean urinary excretion of calcium in this group. In the patients with spinal fractures histomorphometry showed that the osteoid and trabecular resorption surfaces were increased and the relative thickness of the osteoid seams was decreased, indicating increased bone turnover. This evidence was further reinforced by the increased mean serum concentration of 1,25(OH)2D and increased urinary excretion of calcium. The results support the view that these two groups of patients suffer from different forms of osteoporosis.

Adult↗

PubMed1987

Serum selenium, vitamin A, vitamin E and cholesterol concentrations in Finnish and Japanese postmenopausal women.

Serum concentrations of vitamins A and E, selenium, and cholesterol were measured in 30 Finnish and 30 Japanese postmenopausal women. While both groups had identical serum vitamin A levels, the other serum factors differed significantly between the groups, the Finns having higher serum vitamin E and cholesterol and lower serum selenium levels. Adjusted to serum cholesterol, which correlated significantly with vitamin E in both groups, the vitamin E levels were, however, similar in the groups. The differences in the serum levels of these nutritional factors may be associated with the differences in the risk of coronary heart disease and cancer between Finnish and Japanese populations.

Cholesterol↗

PubMed1986

Amniotic fluid 25-hydroxyvitamin D concentrations in normal and complicated pregnancy.

The concentration of 25-hydroxyvitamin D (25(OH)D) was measured in 85 samples of amniotic fluid (AF) obtained near term from mothers with normal pregnancy, diabetes, pre-eclampsia or intrahepatic cholestasis of pregnancy. Significantly lower AF 25(OH)D levels were found in diabetic mothers than in the three other groups. Our results suggest that the vitamin D status of the fetoplacental unit may be somewhat impaired in diabetic pregnancy.

Amniotic Fluid↗

PubMed1986

Vitamin D and mineral metabolism in intrahepatic cholestasis of pregnancy.

Serum concentrations of 25(OH)D, 24,25(OH)2D, 1,25(OH)2D, total protein, calcium, phosphorus, magnesium and alkaline phosphatase were measured in patients with intrahepatic cholestasis of pregnancy and in control subjects at the third trimester of pregnancy and at delivery. 25(OH)D levels of 40.5 +/- 21.5 nmol/l in the patient group were initially significantly (P less than 0.01) higher than the value of 26.3 +/- 9.5 nmol/l in the control group and decreased significantly (P less than 0.01) to 26.0 +/- 16.3 nmol/l at delivery. The levels of active 1,25(OH)2D and inactive 24,25(OH)2D did not alter in either group. Also the concentrations of calcium, phosphorus and magnesium remained unchanged in both groups. No significant differences in fetal vitamin D metabolites were observed between patients and controls, and the other analysed fetal parameters were similar in both groups. Cholestyramine and/or phenobarbital treatment had no influence on vitamin D metabolites. Since levels of 1,25(OH)2D and mineral parameters remained normal and a change in 25(OH)D concentrations was only transient, the clinical role of 25(OH)D variations cannot be substantial.

Bile Acids and Salts↗

PubMed1986

Long-term anticonvulsant therapy and vitamin D metabolism in ambulatory pubertal children.

Parameters of calcium metabolism were thoroughly examined in 28 adolescents with long-term (over 6 years) anticonvulsant therapy (phenytoin, carbamazepine or combination) and in 10 normal controls in September and in March. The adolescents did not receive any vitamin D supplementation during the study. Serum calcium, inorganic phosphorus, parathyroid hormone and alkaline phosphatase levels in the anticonvulsant group did not differ from those of the control group. Serum 25(OH)D and 24,25(OH)2D levels were in all groups consistently higher in September than in March, but no seasonal variation was found in the 1,25(OH)2D levels in any group. The serum 25(OH)D levels in the phenytoin group in March were the lowest among the three groups treated with anticonvulsants, but the levels in the anticonvulsant groups did not differ significantly from each other or from the control group in the same season. The 24,25(OH)2D and 1,25(OH)2D levels in the anticonvulsant groups did not differ significantly from those of control group in September or in March. There was no correlation between anticonvulsant serum free fraction levels and vitamin D metabolites. The bone mineral content in the distal radius was not significantly decreased in the epileptic patients. In conclusion, the long-term anticonvulsant therapy did not induce the so-called "anticonvulsant rickets" in this ambulatory adolescent material. Our data do not indicate that anticonvulsant drugs alter significantly the vitamin D metabolism. Thus, routine vitamin D supplementation does not appear to be indicated in children on anticonvulsant therapy.

Adolescent↗

PubMed1986

Maternal compared with infant vitamin D supplementation.

Vitamin D metabolites were studied in mother-infant pairs at delivery and eight and 15 weeks after that to evaluate the possibility of vitamin D supplementation of infant through the mother. Healthy mothers (n = 49) delivering in January received daily either 2000 IU (group 1), 1000 IU (group 2), or no (group 3) vitamin D. Their infants were exclusively breast fed, and those in group 3 received 400 IU of vitamin D a day. After eight weeks of lactation the infantile vitamin D concentrations were similar in groups 1 and 3 but significantly lower in group 2. The serum 24,25-dihydroxyvitamin D and 1,25-dihydroxyvitamin D concentrations were also lower in group 2. The mean mineral, parathyroid hormone, and alkaline phosphatase values showed no intergroup differences at any point. No infants showed any clinical or biochemical signs of rickets, and their growth was equal. In conclusion, a daily postpartum maternal supplementation with 2000 IU of vitamin D, but not with 1000 IU, seems to normalise the vitamin D metabolites of breast fed infants in winter. Maternal safety with such supplementation over prolonged periods, however, should be examined.

Breast Feeding↗

PubMed1986

Amniotic fluid retinol concentrations in late pregnancy.

The concentrations of retinol (vitamin A) were measured in 36 samples of human amniotic fluid obtained near term. Mothers with normal pregnancy had higher amniotic fluid retinol levels than patients with diabetes or toxemia. The results indicate that some maternal complications during pregnancy affect the transport of retinol into amniotic fluid, possibly due to reductions in the uteroplacental blood flow.

Amniotic Fluid↗

PubMed1986

Serum levels of vitamin D metabolites, calcium, phosphorus, magnesium and alkaline phosphatase in Finnish women throughout pregnancy and in cord serum at delivery.

Serum concentrations of 25(OH)D, 24,25(OH)2D, 1,25(OH)2D, total calcium, protein, phosphorus, magnesium and alkaline phosphatase were measured in two groups of Finnish women throughout pregnancy and in cord serum at delivery. The autumn group delivered in August-September and the spring group in February-March. There was strong seasonal variation in the 25(OH)D concentrations in both groups. Maternal values (mean +/- s.d.) at delivery were 44.3 +/- 20.8 nmol/l in autumn and 26.0 +/- 13.0 nmol/l in spring. Fetal concentrations were 28.8 +/- 14.3 and 18.3 +/- 11.3 nmol/l, respectively. In both mothers and infants low 25(OH)D values were measured in winter. In the autumn group 7 out of 21 mothers (33 per cent) and in the spring group 17 out of 36 mothers (47 per cent) had values below 17 nmol/l, which is the lowest winter reference value recorded in our laboratory. No significant seasonal variation was observed in dihydroxylated vitamin D metabolites, although 24,25(OH)2D values were a little higher in summer than in winter. Concentrations of 1,25(OH)2D tended to rise towards delivery. Corrected calcium, magnesium and phosphorus concentrations did not change during pregnancy. Fetal calcium and phosphorus concentrations were significantly (P less than 0.001) higher than maternal ones. The data indicate that many mothers and infants have poor vitamin D status in the latitude of Finland. Our results support the concept that vitamin D supplementation should be considered in Finland for pregnant women at least in winter.

24,25-Dihydroxyvitamin D 3↗

PubMed1985

Serum levels of vitamins A and E in women with ovarian cancer.

Serum concentrations of the vitamins A and E were measured in 38 postmenopausal women with either malignant, borderline, or benign epithelial ovarian tumors or with a normal ovary. No statistically significant differences were found in the levels of the vitamins between the various groups. The levels of both vitamins in the ovarian vein were also measured in malignant and benign ovarian tumors. The concentration of vitamin A in the ovarian vein of a patient with a malignant tumor was lower than in the peripheral vein, although the difference was not significant. The findings indicate that the vitamin A and E are not of great importance to the metabolism of epithelial ovarian cancer.

Adenocarcinoma, Mucinous↗

PubMed1985

Treatment of Alzheimer's disease with a synthetic ACTH 4-9 analog.

The synthetic ACTH 4-9 analog, Org 2766, was administered to 77 Alzheimer's patients for 6 months in a double-blind, placebo-controlled study. Although Org 2766 was tolerated well, no significant effect of Org 2766 could be demonstrated in terms of rating scales or cognitive functions.

Adrenocorticotropic Hormone↗

PubMed1985

Serum vitamin A and E levels in patients with lichen sclerosus and carcinoma of the vulva--effect of oral etretinate treatment.

Serum vitamin A and E concentrations were determined in six patients with vulvar epithelial carcinoma and in 25 patients with lichen sclerosus and atrophicus (LSA) of the vulva. No difference could be found in these levels between the two groups. LSA patients received oral etretinate for two months at least; improvement was observed in 93% of the patients. Etretinate therapy had no effect on the serum levels of vitamins A or E.

Adult↗