Volume 12, Issue 1

Ferroportin, a membrane protein belonging to the major facilitator superfamily of transporters, is the only vertebrate iron exporter known so far. Several ferroportin mutations lead to the so-called ferroportin disease or type 4 hemochromatosis, characterized by two distinct iron accumulation phenotypes depending on whether the mutation affects the activity of the protein or its degradation pathway. Through extensive molecular modeling analyses using the structure of all known major facilitator superfamily members as templates, multiple structural models of ferroportin in the three mechanistically relevant conformations (inward open, occluded, and outward open) have been obtained. The best models, selected on the ground of experimental data available on wild-type and mutant ferroportion, provide for the first time a prediction at the atomic level of the dynamics of the transporter. Based on these results, a possible mechanism for iron export is proposed.

The human visual system was shaped through natural evolution. We have used artificial evolution to investigate whether depth information and optical flow are helpful for visual control. Our experiments were carried out in simulation. The task was controlling a simulated racing car. We have used The Open Racing Car Simulator for our experiments. Genetic programming was used to evolve visual algorithms that transform input images (color, optical flow, or depth information) to control commands for a simulated racing car. We found that significantly better solutions were found when color, depth, and optical flow were available as input together compared with color, depth, or optical flow alone.

The aim of the study is to present the differences between the human body posture (HBP) of healthy people and those suffering from specific disorders – both those clearly connected with HBP (scoliosis, coxarthrosis) and those seemingly unrelated (e.g. depression). The study was conducted based on the results of photogrammetric measurements of patients standing in a relaxed posture, scanned with a PBE system (Photogrammetrical Body Explorer). Research was conducted over a group of 190 people. Patients were divided into six subgroups based on diagnosed disease entity: coxarthrosis, discopathy, scoliosis, depression, and chronic fatigue syndrome. A control group constituted of 36 healthy volunteers aged 19–29 years, with no identified defects of body posture. To evaluate the differences between the HBP of healthy and sick people, an HBP model based on 29 parameters describing the HBP in three anatomical planes was created. The research showed significant differences in the HBP of healthy and sick people. The results of the analysis indicate that an objective assessment of the HBP can be a source of relevant information on the general health of the patient and may be a useful tool in the diagnosis of selected diseases.

In this work, the multifractal analysis of the kinesiological surface electromyographic signal is proposed. The goal was to investigate the level of neuromuscular activation during complex movements on the laparoscopic trainer. The basic issue of this work concerns the changes observed in the signal obtained from the complete beginner in the field of using laparoscopic tools and the same person subjected to the series of training. To quantify the complexity of the kinesiological surface electromyography, the nonlinear analysis technique, namely, the multifractal detrended fluctuation analysis, was adopted. The analysis was based on the parameters describing the multifractal spectrum – the Hurst exponent – and the spectrum width. The statistically significant differences for a selected group of muscles at the different states (before and after training) are presented. In addition, as the base case, the relaxation state was considered and compared with the working states.

Background: Overdoses of tricyclic antidepressants may lead to arrhythmia. The aim of the study was to simulate the effect of increasing concentrations of amitriptyline (AMI) and its metabolite, nortriptyline, on the action potential of human ventricular cell. Methods: Simulations were performed in Cardiac Safety Simulator platform with the use of the O’Hara-Rudy model. Input data included literature-derived, drug-specific IC50 values for I Ca(L) , I Kr , and I Na currents. Individual concentrations of AMI and nortriptyline were simulated in Simcyp. Nine single doses (mg) were tested: 5, 10, 50, 100, 300, 500, 1000, 5000, and 10,000. Results: The values of simulated endpoints (APD50, APD90, triangulation, and ΔAPD90) increase with drug concentrations. ΔAPD90 was statistically significant for doses up from 1000 mg. EADs were observed after administration of 10,000-mg AMI. Conclusions: The consequences of various doses of AMI on the single cardiac myocytes were simulated in our study. Repolarization abnormalities were not expected for the therapeutic doses. EADs may be observed for very high doses of AMI.

In this review, we present a framework that will enable us to obtain increased accuracy of computer diagnosis in medical patient checkups. To some extent, a new proposition for medical data analysis has been built based on medical data preprocessing. The result of such preprocessing is transformation of medical data from descriptive, semantic form into parameterized math form. A proper model for digging of hidden medical data properties is presented as well. Exploration of hidden data properties achieved by means of preprocessing creates new possibilities for medical data interpretation. Diagnosis selectivity has been increased by means of parameterized illnesses patterns in medical databases.