Health News
Frugal Microbes Reduce The Cost Of Proteins
Bacteria tend to be more frugal when constructing proteins for use outside of the cell versus internally, saving their energy for synthesizing compounds that can be recycled, according to research published in the current issue of the online journal mBioâ¢. Because extracellular proteins are lost to the environment and not recycled like other cellular proteins, they present a greater burden on the cell, as their amino acids cannot be reutilized during translation... (Source: Health News from Medical News Today) Q. A. With a Child Psychiatrist
Are drugs appropriate for toddlers to take when they exhibit troubled behavior? (Source: NYT Health) Arylacetamide Deacetylase Is a Determinant Enzyme for the Difference in Hydrolase Activities of Phenacetin and Acetaminophen [ARTICLES]
Phenacetin was withdrawn from the market because it caused renal failure in some patients. Many reports indicated that the nephrotoxicity of phenacetin is associated with the hydrolyzed metabolite, p-phenetidine. Acetaminophen (APAP), the major metabolite of phenacetin, is also hydrolyzed to p-aminophenol, which is a nephrotoxicant. However, APAP is safely prescribed if used in normal therapeutic doses. This background prompted us to investigate the difference between phenacetin and APAP hydrolase activities in human liver. In this study, we found that phenacetin is efficiently hydrolyzed in human liver microsomes (HLM) [CLint 1.08 ± 0.02 µl/(min · mg)], whereas APAP is hardly hydrolyzed [0.02 ± 0.00 µl/(min · mg)]. To identify the esterase involved in their hydrolysis, the activities were measured using recombinant human carboxylesterase (CES) 1A1, CES2, and arylacetamide deacetylase (AADAC). Among these, AADAC showed a Km value (1.82 ± 0.02 mM) similar to that of HLM (3.30 ± 0.16 mM) and the highest activity [Vmax 6.03 ± 0.14 nmol/(min · mg)]. In contrast, APAP was poorly hydrolyzed by the three esterases. The large contribution of AADAC to phenacetin hydrolysis was demonstrated by the prediction with a relative activity factor. In addition, the phenacetin hydrolase activity by AADAC was activated by flutamide (5-fold) as well as that in HLM (4-fold), and the activity in HLM was potently inhibited by eserine, a strong inhibitor of AADAC. In conclusion, we found that AADAC is the principal enzyme responsible for the phenacetin hydrolysis, and the difference of hydrolase activity between phenacetin and APAP is largely due to the substrate specificity of AADAC.
Is Your Kitchen as Clean as a Restaurant's?
An online quiz rates your hygiene practices with a letter grade -- and gives you the information you need to keep your food safe from bacteria. (Source: WebMD Health) Groups of friends key to changing health behaviors
CHICAGO (Reuters) - When it comes to changing health behaviors, it takes more than a far-flung network of friends on Facebook egging you on. It takes a jostling herd, U.S. researchers said on Thursday. (Source: Reuters: Health) doxazosin mesylate, Cardura
Title: doxazosin mesylate, CardurabrCategory: MedicationsbrCreated: 12/31/1997brLast Editorial Review: 7/13/2010 Easing Sleepless Nights: New Guidelines
Insomnia and other sleep disorders are very common, yet are not generally well understood by doctors and other health care professionals. Now the British Association for Psychopharmacology (BAP) has released up-to-the-minute guidelines in the Journal of Psychopharmacology, published by SAGE, to guide psychiatrists and physicians caring for those with sleep problems... (Source: Health News from Medical News Today)
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