The deoxy-myoglobin (deoxy-Mb)/carbonmonoxy-myoglobin (Mb-CO) UV-vis assay is the principal method used for quantifying the rates of CO release from CO-releasing molecules (CO-RMs) that might possess therapeutic benefits. Some issues emerge when the Mb-CO assay is utilized for testing CO-RMs with novel structures, which are comprehensively discussed here for the first time. Two methods for processing raw UV-vis spectroscopic data generated from the assay are presented in this paper.

The religion-mortality literature has developed in both size and quality over the past decade. Fruitful avenues for continued research include the analysis of (1) more dimensions of religious involvement, including religious life histories; (2) population subgroups, including specific race/ethnic and socioeconomic populations; and (3) a richer set of social, psychologic, and behavioral mechanisms by which religion may be related to mortality.

We assess religious differences in attitudes toward physician-assisted suicide and terminal palliative care, and go further than previous research by attempting to explain these variations. Using data from the 1998 General Social Survey, we fit OLS regression models to estimate the main effects of religious affiliation and indirect effects via religious involvement (church attendance and strength of affiliation). Both conservative and moderate Protestants are generally less accepting of physician-assisted suicide and terminal palliative care than nonaffiliates. However, both relationships are at least partially explained by church attendance and/or strength of affiliation.

Carbon monoxide-releasing molecules (CO-RMs) are compounds capable of delivering controlled amounts of CO within a cellular environment. Ruthenium-based carbonyls [tricarbonyldichloro ruthenium(II) dimer and tricarbonylchloro-(glycinato)ruthenium(II)] and boronacorbonates (sodium boranocarbonate) have been shown to promote vasodilatory, cardioprotective, and anti-inflammatory activities in a variety of experimental models. Here, we extend our previous studies by showing that -4-(4-bromo-6-methyl-2-pyrone)tricarbonyl iron (0) (CORM-F3), an irontricarbonyl complex that contains a 2-pyrone motif, liberates CO in vitro and exerts pharmacological actions that are typical of CO gas. Specifically, CORM-F3 caused vasorelaxation in isolated aortic rings and inhibited the inflammatory response (e.g., nitrite production) of RAW264.7 macrophages stimulated with endotoxin in a dose-dependent fashion. By analyzing the rate of CO release, we found that when the bromide at the 4-position of the 2-pyrone CORM-F3 is substituted with a chloride group [-4-(4-chloro-6-methyl-2-pyrone)tricarbonyl iron (0) (CORM-F8)], the rate of CO release is significantly decreased (4.5-fold), and a further decrease is observed when the 4-and 6-positions are substituted with a methyl group [-4-(4-methyl-6-methyl-2-pyrone)tricarbonyl iron (0) (CORM-F11)] or a hydrogen [-4-(4-chloro-2-pyrone)tricarbonyl iron (0) (CORM-F7)], respectively. Interestingly, the compounds containing halogens at the 4-position and the methyl at the 6-position of the 2-pyrone ring (CORM-F3 and CORM-F8) were found to be less cytotoxic compared with other CO-RMs when tested in RAW246.7 macrophages. Thus, iron-based carbonyls mediate pharmacological responses that are achieved through liberation of CO and the nature of the substituents in the organic ligand have a profound effect on both the rate of CO release and cytotoxicity.

HCHL (hydroxycinnamoyl-CoA hydratase-lyase) catalyses the biotransformation of feruloyl-CoA to acetyl-CoA and the important flavour-fragrance compound vanillin (4-hydroxy-3-methoxybenzaldehyde) and is exploited in whole-cell systems for the bioconversion of ferulic acid into natural equivalent vanillin. The reaction catalysed by HCHL has been thought to proceed by a two-step process involving first the hydration of the double bond of feruloyl-CoA and then the cleavage of the resultant beta-hydroxy thioester by retro-aldol reaction to yield the products. Kinetic analysis of active-site residues identified using the crystal structure of HCHL revealed that while Glu-143 was essential for activity, Ser-123 played no major role in catalysis. However, mutation of Tyr-239 to Phe greatly increased the K(M) for the substrate ferulic acid, fulfilling its anticipated role as a factor in substrate binding. Structures of WT (wild-type) HCHL and of the S123A mutant, each of which had been co-crystallized with feruloyl-CoA, reveal a subtle helix movement upon ligand binding, the consequence of which is to bring the phenolic hydroxyl of Tyr-239 into close proximity to Tyr-75 from a neighbouring subunit in order to bind the phenolic hydroxyl of the product vanillin, for which electron density was observed. The active-site residues of ligand-bound HCHL display a remarkable three-dimensional overlap with those of a structurally unrelated enzyme, vanillyl alcohol oxidase, that also recognizes p-hydroxylated aromatic substrates related to vanillin. The data both explain the observed substrate specificity of HCHL for p-hydroxylated cinnamate derivatives and illustrate a remarkable convergence of the molecular determinants of ligand recognition between the two otherwise unrelated enzymes.