Gene/Protein Disease Symptom Drug Enzyme Compound
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 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Vitamin K deficiency has been reported in patients who were treated with antibiotics and placed on poor diets after surgery. High-performance liquid chromatography (HPLC) was used to study the influence of dietary intake on vitamin K concentrations in surgical patients (n = 22). Plasma phylloquinone decreased rapidly from 1.19 +/- 0.16 to 0.47 +/- 0.12 nmol/L (means +/- SEM, n = 11) on a low-phylloquinone diet and from 1.16 +/- 0.12 to 0.36 +/- 0.07 nmol/L (n = 11) by postoperative fasting. A small amount of phylloquinone and a large amount of menaquinone were found in liver tissue. Phylloquinone concentration was 28.0 +/- 4.3 pmol/g liver (wet weight) on the standard diet (n = 7) whereas it was 6.8 +/- 1.1 pmol/g on the low-phylloquinone diet after 3 d (n = 8). Because phylloquinone is rapidly depleted by fasting, it may be difficult to prevent vitamin K deficiency by dietary phylloquinone alone during long-term fasting after surgery.
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PMID:Vitamin K concentrations in the plasma and liver of surgical patients. 233 43

Hypoprothrombinemia occurs in newborn infants, but it is unclear whether this is the result of reduced production of Factor II precursor or a vitamin K deficient state. In this study, 76 cord blood specimens were analyzed for functional factor coagulant activity and levels of Factor II antigen as determined by electroimmunoassay. In 40 normal term infants, CA = 30% +/- 1.6 (mean +/- SEM) and Ag = 44% +/- 2.3; in 17 normal preterm infants CA = 30% +/- 1.0 and Ag = 31% +/- 4.2; and in 50 normal adults CA = 83 +/- 3 and Ag = 91 +/- 4. In the term infants the average ratio of CA:Ag was 0.90 and in the preterm infants 0.96, both values being similar to those in adults and suggesting underproduction of the precursor form. In 19 term infants who experienced complications of pregnancy and/or delivery, the ratio was 0.76; seven of these ratios were less than 0.70 (range 0.40 to 0.69). These data show that hypoprothrombinemia is common in infant cord blood and is most marked in preterm infants. In the normal infants the CA:Ag ratios were normal, suggesting that the hypoprothrombinemia is the result of reduced production of the protein and not of vitamin K deficiency. However, term infants with complications of labor and delivery had reduced CA:Ag ratios that were suggestive of vitamin K deficiency.
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PMID:Factor II (prothrombin) levels in cord blood: correlation of coagulant activity with immunoreactive protein. 744 31

It is unclear whether menaquinones produced by the intestinal microflora play any role in human nutrition. Reports of coagulopathy due to vitamin K deficiency occurring in patients receiving broad spectrum antibiotics indirectly suggest that vitamin K2 produced by the gut microflora may be utilized by the host. We analyzed the vitamin K1 (phylloquinone) and vitamin K2 (menaquinone) content in a convenience sample of 22 human post-mortem liver samples, including 9 individuals who had been receiving broad spectrum antimicrobials prior to death and 13 individuals who had been victims of sudden, unexpected deaths. There were no significant differences in the mean (+/- SEM) phylloquinone content between the 2 groups [21.9 (+/- 15.5) vs. 16.0 (+/- 9.3) pmol/g wet weight (excluding those who had received supplemental vitamin K1)] but there was a significant difference (p < 0.05) in the total menaquinone (MK) content, 70.0 (+/- 23.3) vs. 423.1 (+/- 141) pmol/g between the 2 groups. These findings suggest an association between receipt of broad spectrum antibiotics and a reduction in hepatic menaquinone concentration, lending support to the hypothesis that a reduction in the gut microflora responsible for their production leads to reduced hepatic stores of this form of the vitamin.
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PMID:Reduction of vitamin K2 concentrations in human liver associated with the use of broad spectrum antimicrobials. 789 17

This randomized, controlled study evaluated the bioavailability of phylloquinone from an intravenous lipid emulsion. A mild vitamin K deficiency was induced in 12 healthy adult men and women by dietary restriction of phylloquinone (40 microg/d, days 1-11) and by administration of warfarin (1.0 mg/d, days 5-11). On day 11, subjects received a 500-mL intravenous solution of either lipid or saline, both of which contained 154 microg phylloquinone. Bioavailability was assessed by serial measurements of plasma phylloquinone, vitamin K1-2,3-epoxide. PIVKA-II (proteins induced by vitamin K absence or antagonists-II), and percentage undercarboxylated osteocalcin. As a result of vitamin K deficiency and minidose warfarin, vitamin K1-2,3-epoxide, PIVKA-II, and percentage undercarboxylated osteocalcin increased significantly between days 1 and 11 (P = 0.05, 0.016, and 0.001, respectively). With the infusions, plasma phylloquinone increased in both groups (P = 0.001). After the infusions vitamin K,-2,3-epoxide decreased in both groups (P = 0.002). Changes in plasma phylloquinone and vitamin K1-2,3-epoxide were no different in the two groups (mean areas under the curves +/- SEM: 116+/-13 nmol x h/L for the saline group and 102+/-20 nmol x h/L for the lipid group for phylloquinone; 38.6+/-7.5 nmol x h/L for the saline group and 31.3+/-9.0 nmol x h/L for the lipid group for vitamin K1-2,3-epoxide). PIVKA-II decreased significantly from baseline values (P = 0.005) in both groups after the infusions. Intravenous lipid reversed the effects of minidose warfarin and of dietary restriction of phylloquinone on hemostasis and vitamin K nutritional status. This reversal was no different from that seen with the infusion of phylloquinone in a saline solution.
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PMID:Bioavailability of phylloquinone from an intravenous lipid emulsion. 953 19