The purpose of this study was to determine the contents of three forms of vitamin K [phylloquinone, dihydrophylloquinone, and menaquinone-4 (MK-4)] in representative samples (including different samples within the same food category) of meat (n = 128), dairy and eggs (n = 24), and fast foods (n = 169) common to the U.S. diet. The findings of our analysis indicate that no single food item in the...

It is now clear that vitamin K1 is part of a biochemical cycle that is essential for the conversion of specific bone peptides into a form that can bind calcium. We have used a recently described procedure for assaying vitamin K1 in plasma to test the involvement of this vitamin in fracture healing. Markedly depressed circulating levels were found in patients with fractures and the time taken fo...

Induced Hypoprothrombinemia By CHARLES G. GUTTAS, M.D., WILLIAM C. MOLONEY, M.D. AND HERBERT S. SI5E, M.D. P HENYLINDANEDIONE, a drung des-eloped! by certain Fretsch ss’orkers because of a more tratssitory prothromhopeisic actiots than dicoumarol,’ has been used extetssively as an anticoagutlatst for the past eighteeis months atthe Bostots City Hospital.3 While phenylitsdatsedione is knosvts to...

The vitamin K-dependent carboxylating system has been solubilized by Lubrol PX or Triton X-100 treatment of vitamin K-deficient rat liver microsomes. As obtained from vitamin K-deficient rat liver, this soluble preparation is dependent upon the in vitro addition of vitamin K1 for carboxylating activity. The enzyme system is complex and is dependent upon NADH and dithiothreitol for maximum activ...

In this paper, we investigate the generalized Hyers-Ulam stability of Jordan homomorphisms in Jordan Banach algebras for the functional equation begin{align*} sum_{k=2}^n sum_{i_1=2}^ksum_{i_2=i_{1}+1}^{k+1}cdotssum_{i_n-k+1=i_{n-k}+1}^n fleft(sum_{i=1,i not=i_{1},cdots ,i_{n-k+1}}^n x_{i}-sum_{r=1}^{n-k+1} x_{i_{r}}right) + fleft(sum_{i=1}^{n}x_{i}right)-2^{n-1} f(x_{1}) =0, end{align*} where ...