Hematopoietic cell transplantation (HCT) prolongs survival in the twitcher mouse, an authentic animal model of human globoid cell leukodystrophy (Krabbe disease; galactosylceramidase deficiency), but the effects of HCT on levels of galactosylceramidase, psychosine, and cerebrosides in the tissues of twitcher mice have not been previously studied. Galactosylceramidase was less than 8% of control...

Four positional isomers of sialyloligosaccharides were isolated from the urine of an adult patient with sialidosis with partial deficiency of beta-galactosidase. From structural studies including compositional sugar analysis, exoglycosidase digestion, chemical ionization mass spectrometry, proton nuclear magnetic resonance spectrometry, and methylation analysis, their structures were deduced to...

Using methyl-1-thio-beta-D-galactoside as the inducer, the biosynthesis of beta-galactosidase was observed in Escherichia coli B with only endogenous sources of nitrogen and energy available. The addition of glucose, ribose, xylose, or glycerol as exogenous energy sources to nitrogen-deficient media blocked enzyme formation. Preinduction of the resting cells failed to overcome inhibition by the...

Extracellular lactase (beta-d-galactosidase, EC 3.2.1.23) was prepared as an ethanol precipitate from a culture of Fusarium moniliforme grown on whey. The enzyme functioned optimally at pH 3.8 to 5.0 and at 50 to 60 degrees C on both o-nitrophenyl-beta-d-galactopyranoside (ONPG) and lactose. The activation energy of the enzymic hydrolysis of ONPG and lactose in the range of 20 to 55 degrees C w...

The apoptosis regulator Bcl-2 has been shown to modulate cell-cycle progression, favouring a quiescent state over a proliferative state, in both normal and tumour cells. We show here that constitutive expression of Bcl-2 in human carcinoma cells results in a cell-cycle arrest that within a few days can become irreversible. Arrested cells acquire a senescent-like phenotype, which consists of sev...

We developed a chemiluminometric assay of beta-galactosidase in coliform bacteria, using a phenylgalactose-substituted 1,2-dioxetane derivative as a substrate. Permeabilization of cells is required to ensure the efficient cellular uptake of this compound. By this method, one coliform seeded in 100 ml of sterile water can be detected after a 6- to 9-h propagation phase followed by a 45-min enzym...

A method to measure enzymatic activity at high temperatures by rapid temperature alternation of a microreactor with a microheater is proposed. On-chip microreactor and microheater were integrated on a glass plate by MEMS technology; this microheater can control the temperature of the microreactor with a response speed of 34.2 and 31.5 K/s for temperature rise and fall, respectively, with an acc...

Jackson, Robert W. (University of California, San Diego, La Jolla), and J. A. DeMoss. Effects of toluene on Escherichia coli. J. Bacteriol. 90:1420-1425. 1965.-When toluene is added at appropriate levels to exponentially growing cultures of Escherichia coli, a time-dependent loss of turbidity is observed which is concurrent with a loss of material to the medium and with unmasking of beta-galact...

It is well known that the property of generalized Lorenz dominance (GLD) between two distributions is a scaled Lorenz dominance, where the scale factor is the ratio of the two finite positive means. It is convenient to test the GLD property between any pair of distributions because, the property is equivalent to the so-called second order stochastic dominance (SSD), whose statistical tests may ...