Potentially toxic trace elements in the muscle of coastal South American fish: Implications for human consumption and health risk assessment.

Micropogonias furnieri and Urophycis brasiliensis are two coastal demersal fish species distributed in the southwestern Atlantic Ocean. Considering that many coastal areas in the southwestern Atlantic Ocean suffer from anthropogenic pressure, the aim of this study was to assess the level of potentially toxic trace elements (Ag, Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, Sr, V and Zn) in the muscle of coastal species, and evaluated the human health risk related to the consumption of muscle. Mercury, inorganic As (As), V, and Se showed a higher contribution to the total THQ.

Selenium speciation in soils using flow injection hydride generation atomic absorption spectrometry with on-line removal of organic matter interferences.

A method based on flow injection hydride generation atomic absorption spectrometry (FI-HGAAS) with an on-line pre-reduction of Se(VI) to Se(IV) was developed and optimized to determine phosphate-extractable Se (0.1 M phosphate buffer KHPO/KHPO at pH 7). The extracted fraction involves water-soluble Se (i.

Structure and function of the bacterial decapping enzyme NudC.

RNA capping and decapping are thought to be distinctive features of eukaryotes. The redox cofactor NAD was recently discovered to be attached to small regulatory RNAs in bacteria in a cap-like manner, and Nudix hydrolase NudC was found to act as a NAD-decapping enzyme in vitro and in vivo. Here, crystal structures of Escherichia coli NudC in complex with substrate NAD and with cleavage product NMN reveal the catalytic residues lining the binding pocket and principles underlying molecular recognition of substrate and product.

Synthesis of 5'-NAD-Capped RNA.

In prokaryotic organisms, certain regulatory RNAs have recently been found to be linked to the ubiquitous redox cofactor nicotinamide adenine dinucleotide (NAD) at their 5'-ends. Biochemical and structural investigations of this new caplike RNA modification require synthetic access to pure NAD-RNA. Here we report a chemoenzymatic approach to generate 5'-NAD-capped RNA in high yields and purity under mild conditions.

The utility of hemodynamic measurements acquired by pulmonary artery catheterization.

Background: Concerns about the utility of pulmonary artery catheters (PAC) stimulated us to assess the impact of one of the parameters measured by the PAC, the pulmonary capillary wedge pressure (PCWP), on our clinical practice.

Methods: The PCWP was recorded at 4- to 6-hour intervals on 50 patients for the first 48 hours following aortic aneurysm repair. We then reviewed the patients' records looking for evidence that the PCWP measurements were used to guide therapy.