Disease model

Introduction

At the beginning of the project, we must explore iron metabolism of a human. This model is the result of this exploration. So, we make a model of a healthy person.

Observations

60% of iron absorption takes place in the duodenum, the last 40% in the jejunum.Duodenum is located on the upper intestines, just after the stomach, and is usually 300mm long. Naturaly, the middle is the duodenum.

Figure 1 : Overview of the iron regulation system in human body.

A healthy person absorbed 10% of the iron uptake of a day (2 mg), while a sick person could absorb between 50% and 100% of the iron uptake in one day ([1]).

Goals

This model is the first step for a sick person with treatment model . So, we want to have a realistic base for the final model.

Assumptions

Constant iron flow
Homogeneous fluid
The patient ingests 20mg of iron per day (Guideline Daily Amounts)

Materials and methods

The duodenum is a cylindrique pipe throw by a homogeneous fluid. So, we three step in the model: the filling of duodenum, steady state step and the emptying. This model have two state variable : iron disolved in the middle (S) and iron absorbed (A).
We considere a constant iron pulse every second arrive in the duodenum. S have a linear composant Sp who represent the pulses. We have the emptying compopsant and finally the absorption composant. We assume a linear absorption and a negative feedback regulation for A. Finally :