Calcium uptake by chorioallantoic membrane: effects of vitamins D and K

1994 ◽  
Vol 267 (6) ◽  
pp. E837-E841 ◽  
Author(s):  
M. A. Elaroussi ◽  
H. F. DeLuca
Keyword(s):  
Vitamin D ◽  
Vitamin K ◽  
Chorioallantoic Membrane ◽  
Binding Activity ◽  
Epithelial Tissue ◽  
Vitamin K Deficiency ◽  
Dihydroxyvitamin D3 ◽  
Ca Uptake ◽  
Membrane Effects ◽  
K Deficiency

The chorioallantoic membrane (CAM) of birds is an epithelial tissue that actively transports large amounts of Ca during embryonic development. In this study the effect of vitamins D and K on Ca uptake by the CAM was studied. Four dietary treatments were used to produce eggs that are the following: deficient in vitamins D and K (-D/-K), sufficient in both (+D/+K), or deficient in one and sufficient in the other (-D/+K or +D/-K). Vitamin D-deficient (-D) Japanese quail embryos (from hens fed 1,25-dihydroxyvitamin D3) do not hatch because of severe Ca deficiency resulting from their inability to obtain Ca from shell, whereas vitamin K deficiency results in only 14% reduction in hatchability. The results demonstrate that Ca uptake by CAM is vitamin D dependent and only slightly vitamin K dependent. Ca-binding activity of CAM extracts was unchanged by vitamin K deficiency, and only a small increase was provided by vitamin D treatment. Vitamin D stimulated both Ca entry and exist from the chorion cells as indicated by the increased accumulated 45Ca in +D embryos. We conclude that vitamin D is essential for the utilization of eggshell Ca by the developing embryo and hence its survival, suggesting that Ca transport across the CAM is largely a vitamin D-dependent process.

Occurrence of vitamin D and vitamin K deficiency in children with low-energy fractures

2017 ◽  
Author(s):  
Michal Karpinski ◽  
Sylwia Chojnowska ◽  
Katarzyna Maresz ◽  
Robert Milewski ◽  
Janusz Popko ◽  
...  
Keyword(s):  
Vitamin D ◽  
Vitamin K ◽  
Low Energy ◽  
Vitamin K Deficiency ◽  
K Deficiency

scholarly journals Vitamin D – contrary to vitamin K – does not associate with clinical outcome in hospitalized COVID-19 patients

2020 ◽  
Author(s):  
Jona Walk ◽  
Anton S.M. Dofferhoff ◽  
Jody M.W. van den Ouweland ◽  
Henny van Daal ◽  
Rob Janssen
Keyword(s):  
Vitamin D ◽  
Clinical Outcome ◽  
Vitamin K ◽  
Elastic Fiber ◽  
Vitamin D Status ◽  
Vitamin K Deficiency ◽  
Fiber Degradation ◽  
K Deficiency ◽  
Mild Deficiency ◽  
Asymptomatic Individuals

AbstractSARS-CoV-2 causes remarkably variable disease from asymptomatic individuals to respiratory insufficiency and coagulopathy. Vitamin K deficiency was recently found to associate with clinical outcome in a cohort of COVID-19 patients. Vitamin D has been hypothesized to reduce disease susceptibility by modulating inflammation, yet little is known about its role in disease severity. Considering the critical interaction between vitamin K and vitamin D in calcium and elastic fiber metabolism, we determined vitamin D status in the same cohort of 135 hospitalized COVID-19 patients by measuring blood 25(OH)D levels. We found no difference in vitamin D status between those with good and poor outcome (defined as intubation and/or death). Instead, we found vitamin D sufficient persons (25(OH)D >50 nmol/L) had accelerated elastic fiber degradation compared to those with mild deficiency (25(OH)D 25-50 nmol/L). Based on these findings, we hypothesize that vitamin D might have both favorable anti-inflammatory and unfavorable pro-calcification effects during COVID-19 and that vitamin K might compensate for the latter.

Problems with Human Milk and Infant Formulas

PEDIATRICS ◽  
1984 ◽  
Vol 74 (4) ◽  
pp. 639-647
Author(s):  
Sanford A. Miller ◽  
Joginder G. Chopra
Keyword(s):  
Vitamin D ◽  
Human Milk ◽  
Vitamin K ◽  
Full Term ◽  
Water Soluble ◽  
Vitamin K Deficiency ◽  
Term Infants ◽  
Water Soluble Vitamin ◽  
K Deficiency ◽  
Breast Fed

EXAMPLES OF PROBLEMS WITH HUMAN MILK Nutritional Problems The adequacy of breast milk as the sole food for the baby is related to the mother's diet during pregnancy and lactation, to maternal calorie reserves in the form of subcutaneous fat, to fetal stores (mainly hepatic), and to birth weight. Although human milk is commonly believed to be a complete, perfect food for infants, deficiencies of vitamin K, vitamin D, and iron may develop in normal, full-term infants breast-fed by apparently healthy women consuming conventional diets. Other nutrient deficiencies may occur in breast-fed infants as a consequence of special conditions existing in the infant, the mother, or both. Normal infants consuming human milk or commercially prepared formulas will receive adequate vitamin K, except in the immediate neonatal period. Because this initial vitamin K deficiency does not become manifest until two or three days after birth, all full-term infants should receive 0.5 to 1 mg of water-soluble vitamin K preparation at delivery.31 Because human milk provides less vitamin K than fortified formulas do, and because breast-fed infants consume relatively small amounts of milk during the first few days of life, vitamin K deficiency in the newborn period is more common is breast-fed than in formula-fed infants.43,69 Thus, parenteral administration of a water-soluble vitamin K preparation to the newborn soon after birth is particularly desirable for breast-fed infants. A report42 that human milk contains appreciable but variable amounts of a water-soluble vitamin D sulfate suggests that the vitamin D content of human milk may be greater than was previously recognized.

Placental Transfer of Vitamin K1 and Its Implications in Fetal Hemostasis

1988 ◽  
Vol 60 (01) ◽  
pp. 039-043 ◽  
Author(s):  
L Mandelbrot ◽  
M Guillaumont ◽  
M Leclercq ◽  
J J Lefrère ◽  
D Gozin ◽  
...  
Keyword(s):  
Vitamin K ◽  
High Performance ◽  
Ultrasound Guidance ◽  
Placental Transfer ◽  
Vitamin K1 ◽  
Vitamin K Deficiency ◽  
Prothrombin Activity ◽  
Oral Supplementation ◽  
K Deficiency ◽  
The Mean

SummaryVitamin K status was evaluated using coagulation studies and/ or vitamin IQ assays in a total of 53 normal fetuses and 47 neonates. Second trimester fetal blood samples were obtained for prenatal diagnosis under ultrasound guidance. Endogenous vitamin K1 concentrations (determined by high performance liquid chromatography) were substantially lower than maternal levels. The mean maternal-fetal gradient was 14-fold at mid trimester and 18-fold at birth. Despite low vitamin K levels, descarboxy prothrombin, detected by a staphylocoagulase assay, was elevated in only a single fetus and a single neonate.After maternal oral supplementation with vitamin K1, cord vitamin K1 levels were boosted 30-fold at mid trimester and 60 fold at term, demonstrating placental transfer. However, these levels were substantially lower than corresponding supplemented maternal levels. Despite elevated vitamin K1 concentrations, supplemented fetuses and neonates showed no increase in total or coagulant prothrombin activity. These results suggest that the low prothrombin levels found during intrauterine life are not due to vitamin K deficiency.

Kinetic Aspects of the Interaction of Blood-Clotting Enzymes

1968 ◽  
Vol 20 (01/02) ◽  
pp. 078-087 ◽  
Author(s):  
H. C Hemker ◽  
A. D Muller
Keyword(s):  
Vitamin K ◽  
Blood Clotting ◽  
Experimental Results ◽  
Factor X ◽  
Clotting Factors ◽  
Vitamin K Deficiency ◽  
K Deficiency

SummaryPIVKA, the circulating anticoagulant protein found in vitamin K deficiency can, on kinetical grounds, be recognized as an analogue of factor X. The existence of analogues of other vitamin K-dependent clotting factors cannot be ruled out, but need not be assumed to explain the experimental results.

Sign in / Sign up

Export Citation Format

Share Document