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AEgis Technologies would like to invite you to attend an online seminar on PK/PD/PBPK Modeling using acslXtreme®.

This online seminar demonstrates the implementation and analysis of pharmacokinetic, pharmacodynamic and physiologically-based pharmacokinetic models using the acslXtreme modeling and simulation environment.

By developing and analyzing a few example models, we will introduce you to the acslXtreme environment and show you how acslXtreme can be used in applications ranging from prediction of drug dispersion and therapeutic thresholds, to determination of exposure limits for toxicological risk assessment.

Topics discussed during the seminar will include:

- Import and exploration of clinical/laboratory data in the acslXtreme environment
- Specification of PK models using both the CSL language and the PK toolkit for graphical modeling
- Estimation of PK parameters using maximum likelihood parameter estimation in acslXtreme
- Linking a PD model to an acslXtreme kinetic model
- Prediction of the effects of various dosing regimens using the acslXtreme analysis language (”M language”)
- Using an acslXtreme PBPK model to predict internal dose metrics from toxic exposure
- Animal to human extrapolation using an acslXtreme PBPK model
- Determination of external exposure limits based on internal dose metrics
- Uncertainty analysis of acslXtreme model predictions using Monte Carlo techniques

On-line Seminars will take place:

Thursday, August 9th, 2007 1:00 PM (CDT) - Full

Tuesday, August 14th, 2007 9:00 AM (CDT)

Tuesday, August 14th, 2007 2:00 PM (CDT)

Register Here for the Seminar

After being away for almost one month due to graduation of my degree and my tight schedule in my home institute, now I have been able to sit behind my laptop again to continue what I have discussed in previous post about finite dose of toxic chemical in this case, barium, Ba. In the last post, finite dose for barium part 1, I have given the example how to measure a simple problem. Fatal dose in known, blood volume is known as well, so we can measure the Ba concentration in the blood associated with the fatal effect.

What I am going to explain in this post is more complex than the previous one. I will give the case of Ba, if entering the body at a time and if Ba is trapped inside the salt, dissolve in the blood stream for a certain period, and how we can measure the concentration of Ba for acute effect and for a certain period of time. Read the rest of this entry »

Bio Transfer Factor (BTF) is a constant to describe the relationship between chemical substance in a tissue and the rate of ingestion to body of particular toxic agent (chemical substance). Often, the concentration forms a linear or straight line as the rate of chemical ingestion inreases as well. Thus at this case, the BTF is constant. I will make this simpler, BTF is a ratio between the amount of chemical per amount of body weight (mg A/kg_tissue) and the rate of ingestion of chemical entering the body (mg A/day. If you do not follow previous post, you are probably unfamiliar with A, A is representing toxic chemicals. I suggest you read the example about physiologically based pharmacokinetics, part 1, part 2 and part 3, especially this example is related to those examples as well. Read the rest of this entry »

When the relationship on a problem between exposed population and cancer risk had a linear curve, sometimes the shape of the curve implies something abut either the data used to find it or a belief in the underlying mechanism causing it. It may the case that the realtionship between radon exposure and lung cancer risk is linear, but then again it may not. Other some possible mechanisms that might cause certain curve shapes, as well as some techniques for simply fitting a curve to data, regardless of possible mecahnisms. Either modeling or simple curve fitting can be used to extrapolate to exposures beuond the data range. Read the rest of this entry »

Physiologically based pharmacokinetic (PBPK) models are stock and flow models used to think about how chemicals move and concentrate within the body. While many dose-response experiments look only at the dose applied to the animal (food, air or skin), understanding what goes on inside the body can provide much better information on why a given response occurs. Read the rest of this entry »

This post will briefly describe about radon and why it is worthy for attention. Radon is present around us, with or without we realize it. Though, radon poses risk to our health, thus it is necessary to reduce its concentration to a certain level believed to be safe for our health. Read the rest of this entry »

As I already described briefly in previous post, modelling is having a good role in determining risk. That is because the concept of modelling is simple yet very useful: use what we know to describe what we observe. The models can be built without using equations or numbers, but at least we ought to have an idea of what is on each axis and how the axes relate. Read the rest of this entry »

In the past post, I have briefly discussed about basic principles of risk relationships which comprise of 4 terms, direct, threshold, concave and convex relationships. On this stage, you should already have been able to give some examples for each of them. At the first time, for each of the relationship, just mention the example whatever cross in your mind. Later on, we will parctice to verify and calibrate all those example you have by comparing them to data. The best answer will be represented by how well the data fit the model and how “good” the data are. Note that bad data may erroneously “confirm” a bad theory. Read the rest of this entry »

So, this post will more or less give the very basic idea about hand waving technique. You should know first about the philosophy behind this technique. What you have to know is how effect or response relate to actions, which we may describe here as dose or exposure. These relationships are basic to familiarize ourself with how we determine our picture in seeing a case or event. Read the rest of this entry »