Extracting Mutual Interaction Rules Using Fuzzy Structured Agent-based Model of Tumor-Immune System Interactions

Background:

There are many studies to investigate the effects of each interacting component of tumor-immune system interactions. In all these studies, the distinct effect of each component was investigated. As the interaction of tumor-immune system has feedback and is complex, the alternation of each component may affect other components indirectly.

Objective:

Because of the complexities of tumor-immune system interactions, it is important to determine the mutual behavior of such components. We need a careful observation to extract these mutual interactions. Achieving these observations using experiments is costly and time-consuming.

Material and Methods:

In this experimental and based on mathematical modeling study, to achieve these observations, we presented a fuzzy structured agent-based model of tumor-immune system interactions. In this study, we consider the confronting of the effector cells of the adaptive immune system in the presence of the cytokines of interleukin-2 (IL-2) and transforming growth factor-beta (TGF-β) as a fuzzy structured model. Using the experimental data of murine models of B16F10 cell line of melanoma cancer cells, we optimized the parameters of the model.

Results:

Using the output of this model, we determined the rules which could occur. As we optimized the parameters of the model using escape state of the tumor and then the rules which we obtained, are the rules of tumor escape.

Conclusion:

The results showed that using fuzzy structured agent-based model, we are able to show different output of the tumor-immune system interactions, which are caused by the stochastic behavior of each cell. But different output of the model just follow the predetermined behavior, and using this behavior, we can achieve the rules of interactions.

Effects of a policy of elective cesarean delivery in cases of suspected fetal macrosomia on the incidence of brachial plexus injury and the rate of cesarean delivery

OBJECTIVE

The aim of this study was to examine the effects of a policy of elective cesarean delivery for suspected fetal macrosomia on the incidence of brachial palsy and on the cesarean delivery rate.

STUDY DESIGN

We performed a retrospective assessment of a policy that recommends cesarean delivery for macrosomia (fetal weight > or =4500 g). Fetal weight was estimated by palpation, and ultrasonographic weight estimation was carried out whenever macrosomia was suspected.

RESULTS

During the 4 years of the study 16,416 deliveries resulted in 133 infants with macrosomia (0.8%). Macrosomia was suspected in 47 cases and confirmed by birth weight in 21 (45%). Antenatal estimation of fetal weight was carried out for 115 of the fetuses with macrosomia (86%). Macrosomia was correctly predicted in 21 of 115 cases (18.3%). Thirteen infants with undiagnosed macrosomia were delivered by emergency cesarean procedures, and 99 were delivered vaginally. Three infants with macrosomia (3%) and 14 infants without macrosomia (0.1%) sustained brachial plexus injury. Our policy prevented at most a single case of brachial palsy, and it contributed 0.16% to our cesarean delivery rate.

CONCLUSIONS

A policy of elective cesarean delivery in cases of suspected fetal macrosomia had an insignificant effect on the incidence of brachial plexus injury. Its contribution to the rate of cesarean delivery was also small.