BACKGROUND N-lactosyl-dioleoylphosphatidylethanolamine (Lac-DOPE) was synthesized and evaluated as a liver-specific targeting ligand via asialoglycoprotein receptors for liposomal delivery of doxorubicin. METHODS Lactosylated liposomes encapsulating calcein (Lac-L-calcein) or doxorubicin (Lac-L-DOX) composed of egg phosphatidylcholine, cholesterol, monomethoxy polyethylene glycol 2000-distear...

Populations of lactose positive (Lac+) and proteinase positive (Prt+) cells from Streptococcus lactis M18, C10, and ML3 grown at 39 degrees C gave rise to increasing proportions of Lac- Prt- clones. The deficiencies did not appear until after a number of generations at the elevated temperature, and the rate depended on the strain.Lac- Prt+ and Lac+ Prt- mutants were isolated after treatment wit...

OBJECTIVE To assess the in vivo peritoneal inflammatory reaction in rats dialyzed with neutral, bicarbonate-lactate-buffered dialysis fluid. METHODS Chronic peritoneal dialysis was performed for 4 weeks in Wistar rats with two solutions: (1) 40 mmol/L lactate-buffered fluid, pH 5.2, with a glucose concentration of 2.27 g/dL (Lac); and, (2) 15 mmol/L lactate and 25 mmol/L bicarbonate-buffered ...

One of the most studied examples of adaptive mutation is a strain of Escherichia coli, FC40, that cannot utilize lactose (Lac-) but that readily reverts to lactose utilization (Lac+) when lactose is its sole carbon source. Adaptive reversion to Lac+ occurs at a high rate when the Lac- allele is on an F' episome and conjugal functions are expressed. It was previously shown that nonselected mutat...

Comparison of the transcriptome of Streptococcus pneumoniae strain D39 grown in the presence of either lactose or galactose with that of the strain grown in the presence of glucose revealed the elevated expression of various genes and operons, including the lac gene cluster, which is organized into two operons, i.e., lac operon I (lacABCD) and lac operon II (lacTFEG). Deletion of the DeoR famil...

Lactobacillus delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis are both used in the dairy industry as homofermentative lactic acid bacteria in the production of fermented milk products. After selective pressure for the fast fermentation of milk in the manufacture of yogurts, L. delbrueckii subsp. bulgaricus loses its ability to regulate lac operon expression. A series of mutations...

Lupus anticoagulant (LAC) testing is important for evaluating patients with antiphospholipid syndromes and hypercoagulable states. We reviewed results of proficiency testing challenges (n = 5) distributed by the North American Specialized Coagulation Laboratory Association to examine LAC testing performed by participating laboratories. The activated partial thromboplastin time (APTT) and dilute...