Five in situ trials with whole-plant corn silage (WPCS) were conducted in two ruminallycannulated Holstein cows to determine 24-h ruminal disappearance of dry matter (DM), starch, and neutral detergent ®ber (NDF). In Trial 1, the effect of maturity of WPCS on ruminal nutrient disappearance was evaluated. Treatments were early dent (ED), 1/4 milk-line (1/4 ML), 2/3 milkline (2/3 ML), and black-l...

Enzymatic hydrolysis of lactose is accompanied by galactosyl transfer to other sugars, thereby producing oligosaccharides. These are hydrolyzed slowly, both in vitro and in vivo. They can be thought of as low molecular weight, non-viscous, water-soluble, dietary fibre. They are considered to be physiologically functional foods which promote the growth of bifidobacteria in the colon and a wide v...

Fully protected CPG-immobilized monomer, dimer and trimer oligonucleotides were used to study depurination during the chemical synthesis of oligonucleotides. Disappearance of the oligonucleotide during acid exposure time relative to an internal thymidine standard not subject to depurination was monitored by reverse phase HPLC analysis. Depurination half-times obtained for dichloroacetic acid (D...

Pure pancreatic juice was collected from the cannulated common bile duct of anesthetized rats after an overnight fast. Digestive enzyme secretion was followed in these animals during and after the progressive degranulation of acinar cells produced by sequentially applied cholinergic stimuli. The kinetics of degranulation, a progressive decrease in the number of zymogen granules in acinar cell...

The protein products of several rad checkpoint genes of Schizosaccharomyces pombe (rad1+, rad3+, rad9+, rad17+, rad26+, and hus1+) play crucial roles in sensing changes in DNA structure, and several function in the maintenance of telomeres. When the mammalian homologue of S. pombe Rad9 was inactivated, increases in chromosome end-to-end associations and frequency of telomere loss were observed....

Actinomycin D produces changes in the cell cycle kinetics of Chinese hamster (HA1) and mouse mammary tumor cells (EMT6) cultivated in vitro. There was a reduced rate of progression of the cells through S phase and a G2 arrest, the duration and degree of which were drug dose dependent. The lethal effects of the drug on the two cell lines were comparable. At the molecular level, DNA single-strand...

The standard mathematical model for stepwise "slow-binding" enzyme inhibition (E+Iright harpoon over left harpoonEIright harpoon over left harpoonEI( *)) assumes that the initial enzyme-inhibitor complex EI is always at equilibrium with the free component species E and I. This assumption implies that the dissociation rate constant (EI-->E+I) is infinitely higher than the isomerization rate cons...

Transient phosphorylation of histidine characterizes the two-component systems in prokaryotes that control important physiological functions, but analogous events have not been implicated in signal transduction in mammalian cells. To explore histidine phosphorylation during activation of human cells, stimulated platelets were analyzed for the formation of protein phosphohistidine in a model sys...

Previous ENDOR studies on reaction centers from Rhodopseudomonas sphaeroides have shown the presence of two hydrogen-bonded protons associated with the primary, ubiquinone, acceptor Q(A). These protons exchange with deuterons from solvent (2)H(2)O. The effect of this deuterium substitution on the charge-recombination kinetics (BChl)(2) (+)Q(A) (-) --> (BChl)(2)Q(A) has been studied with a sensi...