A screening tool to prioritize public health risk associated with accidental or deliberate release of chemicals into the atmosphere

The Chemical Events Working Group of the Global Health Security Initiative has developed a flexible screening tool for chemicals that present a risk when accidentally or deliberately released into the atmosphere. The tool is generic, semi-quantitative, independent of site, situation and scenario, encompasses all chemical hazards (toxicity, flammability and reactivity), and can be easily and quickly implemented by non-subject matter experts using freely available, authoritative information. Public health practitioners and planners can use the screening tool to assist them in directing their activities in each of the five stages of the disaster management cycle

Control of Ion Conduction in L-type Ca(2+) Channels by the Concerted Action of S5–6 Regions

Voltage-gated L-type Ca(2+) channels from cardiac (α(1C)) and skeletal (α(1S)) muscle differ from one another in ion selectivity and permeation properties, including unitary conductance. In 110 mM Ba(2+), unitary conductance of α(1S) is approximately half that of α(1C). As a step toward understanding the mechanism of rapid ion flux through these highly selective ion channels, we used chimeras constructed between α(1C) and α(1S) to identify structural features responsible for the difference in conductance. Combined replacement of the four pore-lining P-loops in α(1C) with P-loops from α(1S) reduced unitary conductance to a value intermediate between those of the two parent channels. Combined replacement of four larger regions that include sequences flanking the P-loops (S5 and S6 segments along with the P-loop-containing linker between these segments (S5–6)) conferred α(1S)-like conductance on α(1C). Likewise, substitution of the four S5–6 regions of α(1C) into α(1S) conferred α(1C)-like conductance on α(1S). These results indicate that, comparing α(1C) with α(1S), the differences in structure that are responsible for the difference in ion conduction are housed within the S5–6 regions. Moreover, the pattern of unitary conductance values obtained for chimeras in which a single P-loop or single S5–6 region was replaced suggest a concerted action of pore-lining regions in the control of ion conduction

A screening tool to prioritize public health risk associated with accidental or deliberate release of chemicals into the atmosphere

The Chemical Events Working Group of the Global Health Security Initiative has developed a flexible screening tool for chemicals that present a risk when accidentally or deliberately released into the atmosphere. The tool is generic, semi-quantitative, independent of site, situation and scenario, encompasses all chemical hazards (toxicity, flammability and reactivity), and can be easily and quickly implemented by non-subject matter experts using freely available, authoritative information. Public health practitioners and planners can use the screening tool to assist them in directing their activities in each of the five stages of the disaster management cycle