3 research outputs found
The basel cocktail for simultaneous phenotyping of human cytochrome P450 isoforms in plasma, saliva and dried blood spots.
BACKGROUND AND OBJECTIVE
Phenotyping cocktails use a combination of cytochrome P450 (CYP)-specific probe drugs to simultaneously assess the activity of different CYP isoforms. To improve the clinical applicability of CYP phenotyping, the main objectives of this study were to develop a new cocktail based on probe drugs that are widely used in clinical practice and to test whether alternative sampling methods such as collection of dried blood spots (DBS) or saliva could be used to simplify the sampling process.
METHODS
In a randomized crossover study, a new combination of commercially available probe drugs (the Basel cocktail) was tested for simultaneous phenotyping of CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6 and CYP3A4. Sixteen subjects received low doses of caffeine, efavirenz, losartan, omeprazole, metoprolol and midazolam in different combinations. All subjects were genotyped, and full pharmacokinetic profiles of the probe drugs and their main metabolites were determined in plasma, dried blood spots and saliva samples.
RESULTS
The Basel cocktail was well tolerated, and bioequivalence tests showed no evidence of mutual interactions between the probe drugs. In plasma, single timepoint metabolic ratios at 2 h (for CYP2C19 and CYP3A4) or at 8 h (for the other isoforms) after dosing showed high correlations with corresponding area under the concentration-time curve (AUC) ratios (AUC0-24h parent/AUC0-24h metabolite) and are proposed as simple phenotyping metrics. Metabolic ratios in dried blood spots (for CYP1A2 and CYP2C19) or in saliva samples (for CYP1A2) were comparable to plasma ratios and offer the option of minimally invasive or non-invasive phenotyping of these isoforms.
CONCLUSIONS
This new combination of phenotyping probe drugs can be used without mutual interactions. The proposed sampling timepoints have the potential to facilitate clinical application of phenotyping but require further validation in conditions of altered CYP activity. The use of DBS or saliva samples seems feasible for phenotyping of the selected CYP isoforms
Rapid response to the earthquake emergency of May 2012 in the Po Plain, northern Italy
Rapid-response seismic networks are an important element
in the response to seismic crises. They temporarily improve
the detection performance of permanent monitoring
systems during seismic sequences. The improvement in earthquake
detection and location capabilities can be important for
decision makers to assess the current situation, and can provide
invaluable data for scientific studies related to hazard, tectonics
and earthquake physics. Aftershocks and the clustering
of the locations of seismic events help to characterize the dimensions
of the causative fault. Knowing the number, size and
timing of the aftershocks or the clustering seismic events can
help in the foreseeing of the characteristics of future seismic
sequences in the same tectonic environment.
Instrumental rapid response requires a high degree of
preparedness. A mission in response to a magnitude (ML) 6
event with a rupture length of a few tens of kilometers
might involve the deployment within hours to days of 30-50
seismic stations in the middle of a disaster area of some hundreds
of square kilometers, and the installation of an operational
center to help in the logistics and communications.
When an earthquake strikes in a populated area, which is almost
always the case in Italy, driving the relevant seismic response
is more difficult. Temporary station sites are chosen
such as to optimize the network geometry for earthquake
locations and source study purposes. Stations have to be installed
in quiet, but easily reachable, sites, and for real-time
data transmission, the sites might need to have optical intervisibility.
The operational center can remain in a town if
there is one within the damaged area, and it should coordinate
the actions of the field teams and provide information
to colleagues, the Civil Protection Authorities and the general
public. The emergency system should operate as long
as the seismic rate remains high; the duration of any mission
might also depend on the seismic history of the area involved.
This study describes the seismic response following
the May 20, 2012, ML 5.9 earthquake in northern Italy, which
included rapid deployment of seismological stations in the
field for real-time seismic monitoring purposes, the coordination
of further instrumental set-ups according to the spatial
evolution of the seismic sequence, and data archiving