Recent reports have shown that responses of midbrain neurons in the guinea pig rapidly shift the dynamic range of their responses to track changes in the statistics of ongoing sound-level distributions. This results in an increased coding accuracy for the most commonly occurring stimulus intensities. To investigate whether this type of adaptation might also be found in other sensory modalities,...

HPr kinase/phosphorylase (HprK/P) controls the phosphorylation state of the phosphocarrier protein HPr and regulates the utilization of carbon sources by Gram-positive bacteria. It catalyzes both the ATP-dependent phosphorylation of Ser-46 of HPr and its dephosphorylation by phosphorolysis. The latter reaction uses inorganic phosphate as substrate and produces pyrophosphate. We present here two...

Carbon catabolite repression (CCR) of several Bacillus subtilis catabolic genes is mediated by ATP-dependent phosphorylation of histidine-containing protein (HPr), a phosphocarrier protein of the phosphoenolpyruvate (PEP): sugar phosphotransferase system. In this study, we report the discovery of a new B. subtilis gene encoding a HPr-like protein, Crh (for catabolite repression HPr), composed o...

The bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) is a multicomponent system that participates in a variety of physiological processes in addition to the phosphorylation-coupled transport of numerous sugars. In Escherichia coli and other enteric bacteria, enzyme IIA(Glc) (EIIA(Glc)) is known as the central processing unit of carbon metabolism and plays multiple roles, incl...

BACKGROUND Aspirin (ASA) reduces adverse events in coronary artery disease (CAD) patients by inhibiting platelets. Some CAD patients have high platelet reactivity (HPR) despite ASA therapy and these individuals have increased risk of adverse events. OBJECTIVE The purpose of this study was to determine the prevalence of HPR in ASA-treated patients referred for coronary angiography and to asses...

BACKGROUND 9-cis-Retinoic acid (9-cis-RA) and N-(4-hydroxyphenyl)retinamide (4-HPR) are effective chemopreventive agents against epithelial tumors in the oral cavity, breast, and prostate. We tested the inhibitory activity of these retinoids against N-nitrosomethylbenzylamine (NMBA)-induced tumorigenesis in the rat esophagus. METHODS Male Fischer 344 rats were randomly assigned to receive die...

Background Enterobacter aerogenes is a facultative anaerobe and is one of the most widely studied bacterial strains because of its ability to use a variety of substrates, to produce hydrogen at a high rate, and its high growth rate during dark fermentation. However, the rate of hydrogen production has not been optimized. In this present study, three strategies to improve hydrogen production in ...

The bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) is a multicomponent system that participates in a variety of physiological processes in addition to the phosphorylation-coupled transport of numerous sugars. In Escherichia coli and other enteric bacteria, enzyme IIA (EIIA) is known as the central processing unit of carbon metabolism and plays multiple roles, including regu...

Bilateral ovariectomy and dietary administration of the retinoid N-(4-hydroxyphenyl)retinamide (4-HPR) are both effective inhibitors of chemical carcinogenesis in the rat mammary gland. The present study was designed to determine whether an enhanced inhibitory effect is obtained with combined ovariectomy and 4-HPR administration, compared to either treatment alone. In separate experiments, 50-d...

Southern blot analyses of genomic DNA show that new world monkeys have only one haptoglobin gene but that chimpanzees, gorillas, orangutans, and old world monkeys have three. Humans have two: haptoglobin (Hp) and haptoglobin-related (Hpr). These observations suggest that a triplication of the haptoglobin locus occurred after the divergence of the new world monkeys, followed by a deletion of one...