We investigated the effects of the antifolate methotrexate on intracellular folate pools of human myeloid precursor cells (MPCs). Immature MPCs, representing 3.2% of the original marrow population, were selected from normal human bone marrow by immune rosetting. The intracellular folate pools were labeled by incubation with 5 X 10(-8) M [3H]5-formyl-FH4 and were quantitated by high performance ...

The transport of Pb2+ through a sensory gel, a polymerized crystalline colloidal array hydrogel with immobilized benzo-18-crown-6, is important for understanding and optimizing the sensor. Square wave voltammetry at a Hg/Au electrode reveals many parameters. The partition coefficient for Pb2+ into a control gel (no crown ether), K(p), is 1.00 +/- 0.018 (errors reported are SEM). The porosity, e...

In the title compound, [Ba(C(14)H(20)O(5))(2)][Co(NCS)(4)], the Ba(II) and Co(II) ions are situated on twofold rotational axes, so asymmetric unit contains half each of the complex cations and anions. The Co(II) ion is coordinated by four N atoms [Co-N 1.83 (2), 1.95 (3) Å] in a distorted tetra-hedral geometry. The Ba(II) ion is coordinated by ten O atoms [Ba-O 2.766 (19)-2.859 (19) Å] from two...

SUMMARY Benzo(a)pyrene and five isomenic phenols of benzo (a)pynene were tested for carcinogenicity by the topical application of 0.4 @moIe of each compound to the backs of C57BL/6J mice once every 2 weeks for 60 weeks. 1-, 3-, and 12-hydroxybenzo(a)pyrene were noncarcinogenic , 11-hy droxybenzo(a)pyrene was weakly carcinogenic, and 2-hy droxybenzo(a)pyrene and benzo(a)pyrene were highly car ci...

A general and versatile molecular design for host molecules was proposed based on the structural motif of antibodies. A water-soluble potassium sensor was developed by this molecular design, which consists of three functional regions, benzo-15-crown-5 ether, DNA, and pyrene as guest-binding, dimerising, and signaling sites, respectively. The molecular sensor emitted the monomer fluorescence of ...

Four half-sandwich type mononuclear lanthanide crown ether complexes with the formula [Ln(12-crown-4)(NO3)3] (Ln3+ = Dy3+ (1), Tb3+ (2), Ho3+ (3), and Er3+ (4); 12-crown-4 = 1,4,7,10-tetraoxacyclododecane) were successfully synthesized and structurally characterized. Ac magnetic susceptibility measurements reveal that dysprosium complex 1 behaves as a typical single-ion magnet, while solid stat...

The first hybrid crown ether with two adjacent disilane fragments was synthesized through reaction of O(Si2Me4Cl)2 (3) with O(C2H4OH)2. By means of DFT calculations, the complexation ability of 1,2,4,5-tetrasila[12]crown-4 (7) towards Li+ was determined to be considerably higher compared to [12]crown-4.